MAO-A (IC50 = 50.1 μM); MAO-B (IC50 = 184.6 μM); COMT (IC50 = 26.7 μM)[1]

In vitro, rosmarinic acid (RA) exhibits a variety of multifunctional characteristics, including antioxidant actions, inhibition of catechol-O-methyltransferase (COMT) and monoamine oxidase (MAO-A and MAO-B). In addition to inhibiting lipid peroxidation (IC50 of 19.6 μM), rosmarinic acid exerts antioxidant effects on hydroxyl (HO(•)) and nitric oxide (NO) free radicals (IC50 of 29.4 and 140 μM, respectively) [1]. Rosmarinic acid (RA) scavenges intracellular ROS produced by UVB rays, hence exhibiting notable cytoprotective properties. In H2O2-treated cells, N-acetyl-L-cysteine (NAC) has a 77% intracellular ROS scavenging activity, whereas 2.5 μM rosmarinic acid may scavenge 60% of intracellular ROS [2].

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Natural products are important sources of chemical diversity leading to unique scaffolds that can be exploited in the discovery of new drug candidates or chemical probes. In this context, chemical and biological investigation of ferns and lycophytes occurring in Brazil is an approach adopted by our research group aiming at discovering bioactive molecules acting on neurodegeneration targets. In the present study, Rosmarinic acid (RA) isolated from Blechnum brasiliense showed an in vitro multifunctional profile characterized by antioxidant effects, and monoamine oxidases (MAO-A and MAO-B) and catechol-O-methyl transferase (COMT) inhibition. RA showed antioxidant effects against hydroxyl (HO(•)) and nitric oxide (NO) radicals (IC50 of 29.4 and 140 μM, respectively), and inhibition of lipid peroxidation (IC50 of 19.6 μM). In addition, RA inhibited MAO-A, MAO-B and COMT enzymes with IC50 values of 50.1, 184.6 and 26.7 μM, respectively. The MAO-A modulation showed a non-time-dependent profile, suggesting a reversible mechanism of inhibition. Structural insights on RA interactions with MAO-A and COMT were investigated by molecular docking. Finally, RA (up to 5 mM) demonstrated no cytotoxicity on polymorphonuclear rat cells. Taken together, our results suggest that RA may be exploited as a template for the development of new antioxidant molecules possessing additional MAO and COMT inhibition effects to be further investigated on in vitro and in vivo models of neurodegenerative diseases. [1]

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This study was designed to investigate the cytoprotective effect of Rosmarinic acid (RA) on ultraviolet B (UVB)-induced oxidative stress in HaCaT keratinocytes. RA exerted a significant cytoprotective effect by scavenging intracellular ROS induced by UVB. RA also attenuated UVB-induced oxidative macromolecular damage, including protein carbonyl content, DNA strand breaks, and the level of 8-isoprostane. Furthermore, RA increased the expression and activity of superoxide dismutase, catalase, heme oxygenase-1, and their transcription factor Nrf2, which are decreased by UVB radiation. Collectively, these data indicate that RA can provide substantial cytoprotection against the adverse effects of UVB radiation by modulating cellular antioxidant systems, and has potential to be developed as a medical agent for ROS-induced skin diseases. [2]

A common phenolic ester molecule found in many plants, particularly in Lamiaceae herbs including prunella vulgaris, salvia, and rosemary, is rosmarinic acid (RA). Through dual suppression of NF-κB and STAT3 activation, rosmarinic acid prevents colon inflammation in mice generated by dextran sulfate sodium (DSS). Treatment with rosmarinic acid (30, 60 mg/kg, oral) significantly reduced the generation of cytokines in a model of colitis produced by DSS [3].

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Ulcerative colitis (UC), a type of inflammatory bowel disease (IBD), is a chronic inflammatory disorder of the colon. Although UC is generally treated with anti-inflammatory drugs or immunosuppressants, most of these treatments often prove to be inadequate. Rosmarinic acid (RA) is a phenolic ester included in various medicinal herbs such as Salvia miltiorrhiz and Perilla frutescens. Although RA has many biological and pharmacological activities, the anti-inflammatory effect of RA in colonic tissue remains unclear. In this study, we investigated the anti-inflammatory effects and underlying molecular mechanism of RA in mice with dextran sulphate sodium (DSS)-induced colitis. In the DSS-induced colitis model, RA significantly reduced the severity of colitis, as assessed by disease activity index (DAI) scores, colonic damage, and colon length. In addition, RA resulted in the reduction of the inflammatory-related cytokines, such as IL-6, IL-1β, and IL-22, and protein levels of COX-2 and iNOS in mice with DSS-induced colitis. Furthermore, RA effectively and pleiotropically inhibited nuclear factor-kappa B and signal transducer and activator of transcription 3 activation, and subsequently reduced the activity of pro-survival genes that depend on these transcription factors. These results demonstrate that RA has an ameliorative effect on colonic inflammation and thus a potential therapeutic role in colitis [3].

In the present study, Rosmarinic acid (RA) isolated from Blechnum brasiliense showed an in vitro multifunctional profile characterized by antioxidant effects, and monoamine oxidases (MAO-A and MAO-B) and catechol-O-methyl transferase (COMT) inhibition. RA showed antioxidant effects against hydroxyl (HO(•)) and nitric oxide (NO) radicals (IC50 of 29.4 and 140 μM, respectively), and inhibition of lipid peroxidation (IC50 of 19.6 μM). In addition, RA inhibited MAO-A, MAO-B and COMT enzymes with IC50 values of 50.1, 184.6 and 26.7 μM, respectively. The MAO-A modulation showed a non-time-dependent profile, suggesting a reversible mechanism of inhibition. Structural insights on RA interactions with MAO-A and COMT were investigated by molecular docking. Finally, RA (up to 5 mM) demonstrated no cytotoxicity on polymorphonuclear rat cells[1].

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Decrease of hydroxyl radical generation [1]
Isolated RA/Rosmarinic acid was diluted in DMSO (final concentration 1%) and phosphate buffer (20 mM, pH 7.2), to obtain final concentrations ranging from 1.22 μM to 5 mM, which were added to the reaction system in 96-well plates, containing 2-deoxyribose, ferrous sulfate (FeSO4) and H2O2, following the method described by Lopes et al. Absorbance readings were performed at 532 nm, measuring the formation of malondialdehyde (product generated by degradation of 2-deoxyribose). Chlorogenic (CGA) and caffeic acids (CA) were used as positive controls. Experiments were performed in triplicate and results were expressed as IC50.

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Antioxidant capacity against nitric oxide radical [1]
To evaluate the scavenger potential of Rosmarinic acid/RA against nitric oxide (NOradical dot) radical, samples (1.22 μM–5 mM) were added to a sodium nitroprusside solution (10 mM) in 96-well plates. Incubations were performed for 60 min, at room temperature. The Griess reagent (1% sulphanilamide and 0.1% N-(1-naphthyl)ethylenediamine dihydrochloride) was added, followed by a 7 min incubation in the dark. Nitrite levels were measured at 546 nm, and the IC50 values were determined for triplicate experiments. The positive controls were CGA and CA.

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AChE and BChE inhibition [1]
The inhibitory properties of Rosmarinic acid/RA on cholinesterases were assessed using the Ellman’s method, modified by Di Giovanni et al. RA was tested in concentrations between 0.5 and 500 μM. Two independent experiments were performed in triplicate.

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MAO-A and MAO-B inhibition [1]
Monoamine oxidase inhibition assays were carried out with a fluorescence based method (end-point reading), using kynuramine as non-selective substrate for MAO-A and MAO-B. Briefly, reactions were performed in black, flat bottom 96-well plates containing potassium phosphate buffer (158 μL, 20 mM, pH 7.4), inhibitor solutions in DMSO (2 μL), 0.5 mM kynuramine solution (20 μL), using a final volume of 200 μL per well. Isolated Rosmarinic acid/RA and other structurally related compounds were tested at concentrations ranging from 0.5 to 500 μM. Solutions of clorgyline and pargyline (from 0.0001 to 1000 μM) were used as positive controls for MAO-A and MAO-B inhibition, respectively. Mixtures were incubated at 37 °C, and then 20 μL of diluted human recombinant MAO-A and MAO-B were added (0.009 and 0.015 mg/mL, respectively). Incubation was carried out at 37 °C, and reactions were stopped with 6 M sodium hydroxide (NaOH) solution (25 μL). The formation of the fluorescent product, 4-hydroxyquinoline (4-OH), was quantified at excitation/emission wavelengths of 310/400 nm. Experiments were performed in quadruplicate.

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Time-dependent studies on MAO-A [1]
To estimate the reversibility of MAO-A inhibition, a time-dependent assay using Rosmarinic acid/RA was employed, according to described by Passos et al. RA was preincubated with human MAO-A (final protein concentration of 0.03 mg/mL) for different periods (0, 15, 30, 60 min), at 37 °C, in potassium phosphate buffer (0.1 M, pH 7.4). For this purpose, RA concentration was equal to twofold the IC50 value determined for MAO-A inhibition. Subsequently, the reaction medium was diluted twofold, by addition of kynuramine to yield a final enzyme concentration of 0.015 mg/mL, and RA concentration corresponding to its IC50. This assay was also performed in 96-well microplates, and the final kynuramine concentration corresponded to 50 μM. Reactions were incubated at 37 °C, for a further 30 min period, and terminated with 6 M NaOH (25 μL). The rates of 4-OH formed in MAO-A reaction were measured and compared with negative control (1% DMSO) to estimate the % of inhibition. All measurements were carried out in triplicate.

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Inhibitory effects on COMT [1]
Modulation of COMT was assessed according to the method proposed by Passos et al., evaluating the conversion of esculetin to scopoletin catalyzed by the enzyme. Substrate conversion, in presence of COMT inhibitors, was performed by fluorescence measurements at λexcitation = 355 nm and λemission = 460 nm. Esculetin (final concentration 6 μM) was incubated with COMT (2.25 U.I./mL) and Rosmarinic acid/RA (15–500 μM) for 5 min, at 37 °C, followed by addition of S-adenosyl-l-methionine (SAM) (100 μM). Plates were incubated at 37 °C, and readings were performed in 4 min intervals, during 60 min, using 3,5-dinitrocathecol (DNC) (35 nM) as positive control. IC50 values were determined for two independent experiments, performed in triplicate.

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Cytotoxicity by LDH release assay (membrane damage) [1]
Cytotoxic effects of isolated Rosmarinic acid/RA on polymorphonuclear cells (PMN) were determined by release of cytosolic LDH (EC1.1.1.27), as described by Andrade et al. PMN (1.5 × 107 cells/mL) were obtained from male Wistar rats blood (180–220 g), and incubated with 0.5 and 5 mM RA, for 30 min, at 37 °C. The enzyme activity in supernatants was measured at 492 nm, using commercial LDH kit. Assays were performed in triplicate, and 1% Triton X-100 was used as positive control.

This study was designed to investigate the cytoprotective effect of rosmarinic acid (RA) on ultraviolet B (UVB)-induced oxidative stress in HaCaT keratinocytes. RA exerted a significant cytoprotective effect by scavenging intracellular ROS induced by UVB. RA also attenuated UVB-induced oxidative macromolecular damage, including protein carbonyl content, DNA strand breaks, and the level of 8-isoprostane. Furthermore, RA increased the expression and activity of superoxide dismutase, catalase, heme oxygenase-1, and their transcription factor Nrf2, which are decreased by UVB radiation. Collectively, these data indicate that RA can provide substantial cytoprotection against the adverse effects of UVB radiation by modulating cellular antioxidant systems, and has potential to be developed as a medical agent for ROS-induced skin diseases[2].

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Cell viability [2]
Cells were treated with Rosmarinic acid/RA (0.625, 1.25, 2.5, or 5 μM) and exposed to UVB radiation 1 h later. They were then incubated at 37°C for 48 h. At this time, MTT was added to each well to obtain a total reaction volume of 200 μl. After 4 h incubation, the supernatant was removed by aspiration. The formazan crystals in each well were dissolved in dimethyl sulfoxide (DMSO; 150 μl), and the absorbance at 540 nm was measured on a scanning multi-well spectrophotometer (Carmichael et al., 1987).

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DPPH radical detection [2]
RA/Rosmarinic acid (0.625, 1.25, 2.5, 5 μM) and 1 mM NAC was added to 0.1 mM DPPH and mixed well. The mixture was incubated for 30 min, after which the amount of residual DPPH was determined by measuring absorbance at 520 nm using a spectrophotometer.

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Intracellular ROS detection [2]
The DCF-DA method was used to detect intracellular ROS levels in HaCaT keratinocytes (Rosenkranz et al., 1992). Cells were seeded at a density of 1.5×105 cells/well in 24-well culture plates. Sixteen hours after plating, cells were treated with Rosmarinic acid/RA (0.625, 1.25, 2.5, 5 μM) or 1 mM NAC. After incubation for 30 min, cells were exposed to H2O2 (1 mM) and again incubated for 30 min. H2O2-treated cells were treated with DCF-DA (25 μM) solution and incubated for another 10 min to detect the fluorescence of DCF. Otherwise, cells were incubated with RA (2.5 μM) or 1 mM NAC for 1 h and exposed to UVB (30 mJ/cm2). Following 24 h, cells were further incubated with DCF-DA solution for 10 min. Fluorescence of DCF was detected using a PerkinElmer LS-5B spectrofluorometer.

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Detection of the superoxide anion [2]
The superoxide anion was produced via the xanthine/xanthine oxidase system and reacted with a nitrone spin trap, DMPO. The DMPO/•OOH adducts were detected using a JES-FA electron spin resonance (ESR) spectrometer (Kohno et al., 1994). Briefly, ESR signaling was recorded 5 min after 20 μl of xanthine oxidase (0.25 unit/ml) was mixed with 20 μl each of xanthine (5 mM), DMPO (1.5 M), Rosmarinic acid/RA (2.5 μM). The ESR spectrometer parameters were set as follows: magnetic field, 336 mT; power, 1.00 mW; frequency, 9.438 GHz; modulation amplitude, 0.2 mT; gain, 500; scan time, 0.5 min; scan width, 10 mT; time constant, 0.03 sec; and temperature, 25°C.

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Detection of hydroxyl radical [2]
The hydroxyl radical was generated via the Fenton reaction (H2O2+FeSO4) and reacted with DMPO. The resultant DMPO/•OH adducts were detected using an ESR spectrometer (Li et al., 2004). The ESR spectrum was recorded 2.5 min after a phosphate buffer solution (pH 7.4) was mixed with 0.2 ml each of DMPO (0.3 M), FeSO4 (10 mM), H2O2 (10 mM), and Rosmarinic acid/RA (2.5 μM). The ESR spectrometer parameters were as follows: magnetic field, 336 mT; power, 1.00 mW; frequency, 9.438 GHz; modulation amplitude, 0.2 mT; gain, 200; scan time, 0.5 min; scan width, 10 mT; time constant, 0.03 sec; and temperature, 25°C.

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Protein carbonyl formation [2]
Cells were treated with Rosmarinic acid/RA at a concentration of 2.5 μM for 24 h. One hour later, cells were exposed to UVB and incubated at 37°C for another 24 h. The extent of protein carbonyl formation was determined using an Oxiselect™ protein carbonyl ELISA kit.

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Lipid peroxidation assay [2]
Lipid peroxidation was assayed by colorimetric determination of the levels of 8-isoprostane, a stable end product of lipid peroxidation, in medium from HaCaT cells (Beauchamp et al., 2002). A commercial enzyme immune assay was employed to detect 8-isoprostane. Lipid peroxidation was also assessed using DPPP as a probe (Okimoto et al., 2000). DPPP reacts with lipid hydroperoxides to generate a fluorescent product, DPPP oxide, thereby providing an indication of membrane damage. Cells were treated with 2.5 μM of Rosmarinic acid/RA for 1 h, followed by exposure to UVB (30 mJ/cm2). Twenty-four hours later, cells were incubated with 20 μM DPPP for 30 min in the dark. Images of DPPP fluorescence were captured on a Zeiss Axiovert 200 inverted microscope at an excitation wavelength of 351 nm and an emission wavelength of 380 nm.

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Nuclear staining with Hoechst 33342 [2]
Cells were treated with 2.5 μM Rosmarinic acid/RA and exposed to 30 mJ/cm2 UVB radiation 1 h later. After incubation for an additional 24 h at 37°C, 1 μl of the DNA-specific fluorescent dye Hoechst 33342 (stock, 15 mM) was added to each well of the 6-well plate. The plate was then incubated for 10 min at 37°C. The degree of nuclear condensation in the stained cells was determined by visualization with a fluorescence microscope equipped with a CoolSNAP-Pro color digital camera.

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DNA fragmentation [2]
Cells were treated with Rosmarinic acid/RA (2.5 μM) for 24 h. One hour later, the cells were exposed to UVB and incubated at 37°C for another 24 h. Cellular DNA fragmentation was assessed by analyzing cytoplasmic histone-associated DNA fragments using a kit from Roche Diagnostics.

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SOD activity assay [2]
Cells were seeded in a culture dish at a concentration of 1×105 cells/ml; 16 h after plating, the cells were treated with 2.5 μM Rosmarinic acid/RA. One hour later, cells were exposed to UVB and incubated at 37°C for an additional 24 h. The cells were then washed with cold PBS and harvested by scraping. The harvested cells were suspended in 10 mM phosphate buffer (pH 7.5) and then lysed on ice by sonicating twice for 15 sec. Triton X-100 (1%) was added to the lysates and incubated for 10 min on ice. The lysates were clarified by centrifugation at 5,000×g for 10 min at 4°C to remove cellular debris. The protein content of the supernatant was determined using the Bradford method. Total SOD activity was evaluated by measuring the level of inhibition of epinephrine auto-oxidation (Misra and Fridovich, 1972), as follows. Fifty micrograms of protein was added to 500 mM phosphate buffer (pH 10.2) and 1 mM epinephrine. Epinephrine rapidly undergoes auto-oxidation at pH 10 to produce adrenochrome, a pink-colored product, which was assayed at 480 nm using a UV/vis spectrophotometer in the kinetic mode. SOD inhibits the auto-oxidation of epinephrine. The rate of inhibition was monitored at 480 nm, and the amount of enzyme required to produce 50% inhibition was defined as 1 unit of enzyme activity. Total SOD activity was expressed as units/mg protein.

In this study, we investigated the anti-inflammatory effects and underlying molecular mechanism of RA/Rosmarinic acid in mice with dextran sulphate sodium (DSS)-induced colitis. In the DSS-induced colitis model, RA significantly reduced the severity of colitis, as assessed by disease activity index (DAI) scores, colonic damage, and colon length. In addition, RA resulted in the reduction of the inflammatory-related cytokines, such as IL-6, IL-1β, and IL-22, and protein levels of COX-2 and iNOS in mice with DSS-induced colitis. Furthermore, RA effectively and pleiotropically inhibited nuclear factor-kappa B and signal transducer and activator of transcription 3 activation, and subsequently reduced the activity of pro-survival genes that depend on these transcription factors. These results demonstrate that RA has an ameliorative effect on colonic inflammation and thus a potential therapeutic role in colitis.[3]

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Induction of colitis [3]
Experimental colitis was induced by giving mice drinking water ad libitum containing 5% (w/v) DSS for 7 days. Mice of each of the groups were monitored carefully every day to confirm that they had consumed an approximately equal volume of water containing DSS. For each experiment, the mice were divided into five experimental groups (n = 10/group). The first group was kept as the vehicle-treated control, and the second group was given drinking water with DSS only during the experimental period. The other three groups consisted of mice receiving 5% DSS who were administrated 5-ASA (75 mg/kg/day p.o.) or Rosmarinic acid (30 or 60 mg/kg/day p.o.) daily for 7 days, according to the experimental design. All materials were dissolved in a vehicle of 0.9% saline. Control groups were given the vehicle daily for 7 days as appropriate. Administration of each drug was initiated simultaneously with the DSS treatment.

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Evaluation of disease activity index (DAI) [3]
Body weight, stool consistency, and gross bleeding were recorded daily. Disease activity index (DAI) was determined by combining the scores for (i) body weight loss, (ii) stool consistency, and (iii) gross bleeding, divided by 3. Each score was determined as follows: change in body weight loss (0: none, 1: 1–5%, 2: 5–10%, 3: 10–20%, 4: > 20%), stool blood (0: negative, 1: +, 2: ++, 3: +++, 4: ++++), and stool consistency (0: normal, 1 and 2: loose stool, 3 and 4: diarrhoea). Body weight loss was calculated as the percentage of the difference between the original body weight (day 0) and the body weight on any particular day (Table 1). At the end of experiment, all mice were sacrificed and the large intestines were separated from the vermiform appendix to the anus. The colon length was measured between the caecum and proximal rectum. The spleens were dissected and their weights measured immediately.

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Histopathology [3]
The resected mice colon tissues were fixed immediately in 10% formalin and embedded. For histopathological analysis, tissue samples were sectioned (5 μm) and stained with haematoxylin and eosin (H&E) and periodic acid-Schiff (PAS). Both of the histologic processes were described previously.

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Measurement of myeloperoxidase activity (MPO) and cytokine production [3]
Colon tissues were washed with DMEM medium containing 0.2% FBS, streptomycin, and penicillin, and cut into smaller pieces. Afterwards, 0.5 cm of the tissue was placed in a 24-well plate filled with 1 ml DMEM medium containing 0.2% FBS, streptomycin, and penicillin, and incubated for 24 h at 37 °C in 5% CO2. The cell-free culture supernatants of the colon tissue were used to measure MPO activity and production of cytokines. Neutrophil sequestration in the colon was quantified by measuring tissue MPO activity. To estimate MPO activity, tissue samples were thawed and homogenized in 0.05 M phosphate buffer (pH 6) containing 0.5% (w/v) hexadecyltrimethylammonium bromide. The suspension was centrifuged (3,000 rpm, 20 min, 4 °C), and the supernatant was used for MPO assay. The reaction mixture consisted of the supernatant, 0.003% H2O2, O-dianiside in 0.05 M phosphate buffer (pH 6), and 0.5% HTAB. This mixture was incubated at 37 °C and terminated at 10 min. The absorbance was measured at 450 nm. The results were quantified as the amount from 10 min absorbance minus the amount from zero min absorbance, and expressed as unit per milligram of protein. In addition, the levels of IL-1β, IL-6, and IL-22 produced in the culture media were quantified using EIA kits, according to the manufacturer’s instructions.

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Inflammation score [3]
The inflammation score was evaluated based on Table 2. Inflammation was graded as follows: mucosal epithelial cell 1, prolonged epithelial cell or crypt; 2, destruction of barrier; 3, ulcer (30% < loss < 60%); 4, ulcer (loss > 60%), mucosal immune cell 1, infiltration (mild); 2, infiltration (moderate); 3, infiltration (severe) and submucosa’s immune cell 1, infiltration (mild); 2, infiltration (moderate); 3, infiltration (severe). Immunohistochemistry [3]
All IHC was performed on formalin-fixed, paraffin-embedded samples. Paraffin blocks were sectioned to 5-μm thickness. Afterwards, poly-L-lysine-coated slides were used to promote adhesion of the paraffin-section to the slides, which were then dried. The dried slides were de-paraffinized, and antigen retrieval was performed by automated antigen retrieval machine for 20 minutes in cell condition solution (Ethylenediaminetetraacetic acid pH 9.0). Sections were blocked for 1 h with 15–20% normal goat serum, prior to incubation with primary antibody for 2 h at room temperature or overnight at 4 °C. Secondary rabbit antibodies were used to detect primary antibodies, followed by streptavidin-tagged horseradish peroxidase. Diaminobenzidine was used to induce signalling, and bluing reagent was used as a counterstain. Images of IHC slides were visualized by optical microscopy and rendered using Leica software. For IHC, p-STAT3 (Tyr705) and NF-κB p65 antibodies were used.

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Detection of thiobarbituric acid reactive substances (TBARS) [1]
Experiments to evaluate lipid peroxidation were performed in homogenates of cortex and hippocampus from male Wistar rats (180–220 g). Brain regions were washed with cold TRIS buffer (20 mM, pH 7.4) and homogenized. The pool of cells was centrifuged in a HT-MCD 2000 at 4592g for 5 min, and supernatant was removed. The Rosmarinic acid/RA was diluted in phosphate buffer (20 mM, pH 7.2) containing 1% DMSO to obtain concentrations ranging from 0.001 to 5 mM, which were added to supernatant of brain homogenates. FeSO4 (2 mM) and ascorbic acid (0.02 mM) solutions were also added to the medium and incubated at 37 °C, for 60 min. Subsequently, trichloroacetic and thiobarbituric acids were added, followed by 20 min incubation, at 80 °C. Centrifugation at 7500 rpm for 10 min was taken, and supernatants were analyzed at 532 nm. Analyzes were carried out in triplicate and positive controls CGA and CA were employed. Percentage inhibition (%) were calculated comparing with the negative control (1% DMSO) and results were expressed as IC50 values.

Absorption, Distribution and Excretion
The aim of this study in healthy humans was to determine the absorption, metabolism, and urinary excretion of rosmarinic acid (RA) after a single intake of perilla extract (PE). Six healthy men (mean age 37.2 +/- 6.2 y and mean body mass index 22.0 +/- 1.9 kg/sq m) were enrolled in the study that was a crossover design involving single intakes of PE containing 200 mg RA and placebo with a 10 day interval between treatments. Blood samples were collected before intake and at designated time intervals, while urine samples were collected over the periods 0-6 hr, 6-24 hr and 24-48 hr after intake. RA and its related metabolites in plasma and urine were measured by LC-MS. RA, methylated RA (methyl-RA), caffeic acid (CAA), ferulic acid (FA) and a trace of m-coumaric acid (COA) were detected in the urine after intake of PE. In plasma, RA, methyl-RA and FA were detected, with maximum levels obtained 0.5, 2 and 0.5 hr after intake of PE, respectively. The majority of these components in both plasma and urine were present as conjugated forms (glucuronide and/or sulfated). The proportion of RA and its related metabolites excreted in the urine was 6.3 +/- 2.2% of the total dose, with approximately 75% of these components being excreted within 6 hr after intake of PE.
Rosmarinic acid is well absorbed from gastrointestinal tract and from the skin.
The purpose of the study was to investigate the transdermal absorption of rosmarinic acid (RA), its tissue distribution and absolute bioavailability. In ex vivo experiments, permeation of RA across excised rat skin was about 8 times higher from alcoholic solution than from water, indicating that ethanol may act as sorption promoter. The flux from water or alcoholic solution was 4.4 or 10 ug/sq cm/hr, and the tleg was 7.8 or 3.7 hr, respectively. After I.V. administration, RA is best described by a 2-compartment open model; t1/2 = 1.8 hr, t1/2 alpha = 0.07 hr, V tau = 2.3 L/kg, V beta = 15.3 L/kg. Upon topical administration of RA in form of a W/O ointment (25 mg/kg, 50 sq cm), the absolute bioavailability was 60%. 0.5 hours after iv administration, RA was detected and measured in brain, heart, liver, lung, muscle, spleen and bone tissue, showing the highest concentration in lung tissue (13 times the blood concentration), followed by spleen, heart and liver tissue. 4.5 hours (peak time) after topical administration of about 3 mg on the hind leg over 20 sq cm, RA was measured in blood, skin, muscle and bone tissue.

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Metabolism / Metabolites
The urine of rats administered rosmarinic acid (7) orally contained seven metabolites, which were identified as trans-caffeic acid 4-O-sulfate (1), trans-m-coumaric acid 3-O-sulfate (2), trans-ferulic acid 4-O-sulfate (3), trans-caffeic acid (4), m-hydroxyphenylpropionic acid (5), trans-m-coumaric acid (6), and unchanged rosmarinic acid (7) by spectroscopic and chemical data. The total cumulative amount of 1-7 excreted in the urine 48 h after the oral administration of rosmarinic acid was approximately 31.8% of the dose administered. On the other hand, the metabolites attributed to rosmarinic acid could not be found in the bile. Orally administered rosmarinic acid may thus be concluded to be excreted in the urine rather than in the bile, with cleavage of ester bonds, selective para-dehydroxylation, methylation, and sulfate-conjugation. Metabolites 2, 3, 5, and 6 were also detected in the plasma.
Rosmarinic acid is the dominant hydroxycinnamic acid ester accumulated in Boraginaceae and Lamiaceae plants. A cytochrome P450 cDNA was isolated by differential display from cultured cells of Lithospermum erythrorhizon, and the gene product was designated CYP98A6 based on the deduced amino acid sequence. After expression in yeast, the P450 was shown to catalyze the 3-hydroxylation of 4-coumaroyl-4'-hydroxyphenyllactic acid, one of the final two steps leading to rosmarinic acid. The expression level of CYP98A6 is dramatically increased by addition of yeast extract or methyl jasmonate to L. erythrorhizon cells, and its expression pattern reflected the elicitor-induced change in rosmarinic acid production, indicating that CYP98A6 plays an important role in regulation of rosmarinic acid biosynthesis.
The aim of this study in healthy humans was to determine the absorption, metabolism, and urinary excretion of rosmarinic acid (RA) after a single intake of perilla extract (PE). Six healthy men (mean age 37.2 +/- 6.2 y and mean body mass index 22.0 +/- 1.9 kg/sq m) were enrolled in the study that was a crossover design involving single intakes of PE containing 200 mg RA and placebo with a 10 day interval between treatments. Blood samples were collected before intake and at designated time intervals, while urine samples were collected over the periods 0-6 hr, 6-24 hr and 24-48 hr after intake. RA and its related metabolites in plasma and urine were measured by LC-MS. RA, methylated RA (methyl-RA), caffeic acid (CAA), ferulic acid (FA) and a trace of m-coumaric acid (COA) were detected in the urine after intake of PE. In plasma, RA, methyl-RA and FA were detected, with maximum levels obtained 0.5, 2 and 0.5 hr after intake of PE, respectively. The majority of these components in both plasma and urine were present as conjugated forms (glucuronide and/or sulfated). The proportion of RA and its related metabolites excreted in the urine was 6.3 +/- 2.2% of the total dose, with approximately 75% of these components being excreted within 6 hr after intake of PE.

Interactions
Rosmarinic acid (RA), a caffeic acid ester, has insulin-sensitizing and antioxidant effects in high fructose-fed model of insulin resistance (IR). This study investigated whether RA supplementation prevents cardiac abnormalities and hypertension in fructose-fed rats (FFR). Rats fed with fructose diet (60 g/100 g) for 60 days exhibited metabolic abnormalities and rise in plasma and cardiac lipids and whole body IR. The levels of cardiac antioxidants and plasma ferric reducing antioxidant power were significantly reduced in FFR concomitant with increased levels of lipid peroxidation and protein oxidation products. A significant rise in troponin T, creatine kinase-MB, aspartate transaminase, and lactate dehydrogenase in plasma of FFR was noted. RA supplementation to FFR (10 mg/kg from the 16th day) significantly improved insulin sensitivity, reduced lipid levels, oxidative damage, and the expression of p22phox subunit of nicotinamide adenine dinucleotide phosphate reduced oxidase, and prevented cardiac hypertrophy. Fructose-induced rise in blood pressure was also lowered by RA through decrease in endothelin-1 and angiotensin-converting enzyme activity and increase in nitric oxide levels. Histology revealed a reduction in myocardial damage in RA-supplemented FFR. These findings suggest that RA acts as a vasoactive substance and a cardioprotector through its antioxidant property. Thus, RA may be useful in reducing the cardiovascular risk associated with IR.
Epidemiological and experimental studies have suggested that diesel exhaust particles (DEP) may be involved in recent increases in lung diseases. DEP has been shown to generate reactive oxygen species. Intratracheal instillation of DEP induces lung inflammation and edema in mice. Rosmarinic acid is a naturally occurring polyphenol with antioxidative and anti-inflammatory activities. /This/ investigated the effects of rosmarinic acid on lung injury induced by intratracheal administration of DEP (500 ug/body) in mice. Oral supplementation with administration of rosmarinic acid (2 mg/body for 3 d) inhibited DEP-induced lung injury, which was characterized by neutrophil sequestration and interstitial edema. DEP enhanced the lung expression of keratinocyte chemoattractant (KC), interleukin-1beta, monocyte chemoattractant protein-1, and macrophage inflammatory protein-1alpha, which was inhibited by treatment with rosmarinic acid. DEP enhanced expression of iNOS mRNA and formation of nitrotyrosine and 8-OHdG in the lung, which was also inhibited by rosmarinic acid. These results suggest that rosmarinic acid inhibits DEP-induced lung injury by the reduction of proinflammatory molecule expression. Antioxidative activities of rosmarinic acid may also contribute to its protective effects.
Rosmarinic acid (RA), a polyphenolic phytochemical, is a natural prolyl oligopeptidase inhibitor. /The present study/ found that RA exerted potent anti-inflammatory effects in in vivo models of acute lung injury (ALI) induced by lipopolysaccharide (LPS). Mice were pretreated with RA one hour before challenge with a dose of 0.5 mg/kg LPS. Twenty-four hours after LPS was given, bronchoalveolar lavage fluid (BALF) was obtained to measure pro-inflammatory mediator and total cell counts. RA significantly decreased the production of LPS-induced TNF-a, IL-6, and IL-1beta compare with the LPS group. When pretreated with RA (5, 10, or 20 mg/kg) the lung wet-to-dry weight (W/D) ratio of the lung tissue and the number of total cells, neutrophils and macrophages in the BALF were decreased significantly. Furthermore, RA may enhance oxidase dimutase (SOD) activity during the inflammatory response to LPS-induced ALI. And /the authors/ further demonstrated that RA exerts anti-inflammation effect in vivo models of ALI through suppresses ERK/MAPK signaling in a dose dependent manner...
The aim of the present work was to study the protective effects of rosmarinic acid against ethanol-induced DNA damage in mice. The antigenotoxic capacity of rosmarinic acid (100 mg/kg) was tested using pre-, co- and post-treatment with ethanol (5 g/kg). Peripheral blood (1 and 24 hr) and brain cells (24 hr) were evaluated using the comet assay and bone marrow was analyzed using the micronucleus assay (24 hr). The results were compared to data of TBARS, enzymes with antioxidant activity, and DCFH-DA test. Peripheral blood and brain cells show that mean damage index (DI) and damage frequency (DF) values of ethanol with pre-treatment with rosmarinic acid group were significantly lower than in the ethanol group. In brain cells all different treatments with ethanol and rosmarinic acid showed significant decrease in DI and DF mean values when compared to ethanol group and negative control. No significant differences were observed in micronucleus frequency, activity of antioxidant enzymes and TBARS between groups. The DCFH-DA test show a reduction of 18% of fluorescence intensity when compare with ethanol group. The results show that rosmarinic acid could decrease the levels of DNA damage induced by ethanol, for both tissues and treatment periods.
For more Interactions (Complete) data for ROSMARINIC ACID (13 total), please visit the HSDB record page.

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mouse LD50 intravenous 561 mg/kg Drugs of the Future., 10(756), 1985

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Antidote and Emergency Treatment
/SRP:/ Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR if necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on the left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Poisons A and B/

/SRP:/ Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if needed. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Monitor for shock and treat if necessary ... . Anticipate seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 mL/kg up to 200 mL of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool ... . Cover skin burns with dry sterile dressings after decontamination ... . /Poisons A and B/

/SRP:/ Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Positive-pressure ventilation techniques with a bag valve mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Consider administering a beta agonist such as albuterol for severe bronchospasm ... . Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload ... . Treat seizures with diazepam or lorazepam ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Poisons A and B/ Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3Rd edition, Elsevier Mosby, St. Louis, MO 2005, p. 160-1

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Human Toxicity Excerpts
/HUMAN EXPOSURE STUDIES/ Rosmarinic acid is known to have anti-inflammatory and immunomodulatory activities. This study was performed to evaluate the effect of rosmarinic acid on atopic dermatitis (AD), one of the inflammatory disorders of the skin. Twenty-one subjects (14 women and seven men, 5-28 years of age) with mild AD participated in this study. Rosmarinic acid (0.3%) emulsion was topically applied to the elbow flexures of AD patients twice a day (once in the morning and once in the evening). All subjects were evaluated for skin conditions before treatment at the first visit, and then at 4 and 8 weeks after treatment. According to local Severity Scoring of Atopic Dermatitis index results, erythema on antecubital fossa was significantly reduced at 4 and 8 weeks (P < 0.05). Transepidermal water loss of the antecubital fossa was significantly reduced at 8 weeks compared to before treatment (P < 0.05). ... PMID:19239556

/ALTERNATIVE and IN VITRO TESTS/ The protective effects of rosmarinic acid (RA) on H(2)O(2)-induced neurotoxicity in human dopaminergic cell line, SH-SY5Y /were investigated/. Results showed that RA significantly attenuated H(2)O(2)-induced reactive oxygen species (ROS) generation and apoptotic cell death. Rosmarinic acid effectively suppressed the up-regulation of Bax and down-regulation of Bcl-2. Furthermore, RA stimulated the antioxidant enzyme heme oxygenase-1 (HO-1). ... The HO-1 induction by RA was associated with the protein kinase A (PKA) and phosphatidylinositiol-3-kinase (PI3K) signaling pathways. These results suggest that RA can protect SH-SY5Y cells under oxidative stress conditions by regulating apoptotic process... PMID:18644421

/ALTERNATIVE and IN VITRO TESTS/ ... This study ... evaluated the cytoprotective effects of two sage extracts (a water and a methanolic extract) against tert-butyl hydroperoxide (t-BHP)-induced toxicity in HepG2 cells. The most abundant phenolic compounds present in the extracts were rosmarinic acid and luteolin-7-glucoside. Both extracts, when co-incubated with the toxicant, protected significantly HepG2 cells against cell death. The methanolic extract, with a higher content of phenolic compounds than the water extract, conferred better protection ... . Both extracts, tested in a concentration that protects 80% against cell death (IC(80)), significantly prevented t-BHP-induced lipid peroxidation and GSH depletion, but not DNA damage assessed by the comet assay... PMID:17349617

/ALTERNATIVE and IN VITRO TESTS/ UVA radiation provokes the generation of reactive oxygen species (ROS), which induce oxidative stress in the exposed cells leading to extensive cellular damage and cell death either by apoptosis or necrosis. One approach to protecting human skin against the harmful effects of UV radiation is by using herbal compounds as photoprotectants. This study evaluated the protective effects of Prunella vulgaris L. (Labiatae) and its main phenolic acid component, Rosmarinic acid (RA), against UVA-induced changes in a human keratinocyte cell line (HaCaT). Human keratinocytes exposed to UVA (10-30 J/sq cm) were treated with an extract of P. vulgaris (1-75 mg/L) or RA (0.9-18 mg/L) for 4 hr. P. vulgaris and RA exhibited ability to reduce the UVA-caused decrease in a cell viability monitored by neutral red retention and by LDH release into medium. The P. vulgaris extract and RA significantly suppressed UVA-induced ROS production, which manifests as a decrease in intracellular lipid peroxidation, elevation of ATP and reduced glutathione. Post-treatment with P. vulgaris extract and RA also significantly reduced DNA damage. In addition, UVA-induced activation of caspase-3 was inhibited by treatment with P. vulgaris and RA. The P. vulgaris extract and RA demonstrated a concentration-dependent photoprotection (maximum at 25-50 mg/L and 9 mg/L, respectively). These results suggest that P. vulgaris and RA, used in skin care cosmetics, may offer protection against UVA-induced oxidative stress and may be beneficial as a supplement in photoprotective dermatological preparations. PMID:16631374

[1]. Combining in vitro and in silico approaches to evaluate the multifunctional profile of rosmarinic acid from Blechnum brasiliense on targets related to neurodegeneration. Chem Biol Interact. 2016 Jul 25;254:135-45.

[2]. Rosmarinic Acid Attenuates Cell Damage against UVB Radiation-Induced Oxidative Stress via Enhancing Antioxidant Effects in Human HaCaT Cells. Biomol Ther (Seoul). 2016 Jan;24(1):75-84.

[3]. Rosmarinic acid suppresses colonic inflammation in dextran sulphate sodium (DSS)-induced mice via dual inhibition of NF-κB and STAT3 activation. Sci Rep. 2017 Apr 6;7:46252.

Therapeutic Uses
/EXPL THER/ Melissa officinalis L. (Lamiaceae) (lemon balm) is used in folk medicine for nervous complaints, lower abdominal disorders and, more recently, for treating Herpes simplex lesions. In this work the antiviral activity of a hydroalcoholic extract of lemon balm leaves against the Herpes simplex virus type 2 (HSV-2) was assessed by the cytopathic effect inhibition assay on Vero cells (ATCC CCL-81), in comparison with acyclovir. The cytotoxicity of the extract on Vero cells was previously tested by evaluating the cellular death and was confirmed by the Trypan blue test. Lemon balm showed to reduce the cytopathic effect of HSV-2 on Vero cells, in the range of non-toxic concentrations of 0.025-1 mg/mL (with reference to the starting crude herbal material). The maximum inhibiting effect (60%) was obtained with 0.5 mg/mL. The viral binding assay showed that the extract does not prevent the entry of HSV-2 in the cells, thus suggesting a mechanism of action subsequent to the penetration of the virus in the cell. The extract was also chemically characterized by NMR and HPLC analysis; it showed to contain cinnamic acid-like compounds, mainly rosmarinic acid (4.1% w/w). /The/ experiments support the use of lemon balm for treating Herpes simplex lesions and encourage clinical trials on this medicinal plant.

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Mechanism of Action
... To determine the effects of rosmarinic acid on melanogenesis and elucidate the molecular events of melanogenesis induced by rosmarinic acid, several experiments were performed in B16 melanoma cells. In this study, ... the melanin content and tyrosinase expression were increased by rosmarinic acid in a concentration-dependent manner. In addition, after the melanin content was increased by rosmarinic acid, it was reduced by H-89 and KT 5720, protein kinase A (PKA) inhibitors, but not by SB203580, a p38mapk inhibitor, or Ro-32-0432, a PKC inhibitor, which suggests the involvement of PKA in rosmarinic acid-induced melanogenesis. Consistent with this, rosmarinic acid induced the phosphorylation of CRE-binding protein (CREB), but had no effect on the phosphorylation of p38mapk or the inhibition of Akt phosphorylation. Additionally, rosmarinic acid induced the activation of cAMP response element (CRE) without having any effect on cAMP production, which suggests that rosmarinic acid-induced melanogenesis is mediated by PKA, which occurs downstream of cAMP production. This result was further confirmed by the fact that rosmarinic acid-induced phosphorylation of CREB was inhibited by H-89, but not by PD98059, a MEK1 inhibitor, or by LY294002, a phosphatidylinositol-3-kinase (PI3K) inhibitor. Rosmarinic acid-induced expression of tyrosinase protein was attenuated by H-89. Based on these results, ... rosmarinic acid induces melanogenesis through PKA activation signaling. PMID:17651699

Rosmarinic acid (RA) ... inhibits several complement-dependent inflammatory processes and may have potential as a therapeutic agent for the control of complement activation in disease. Rosmarinic acid has been reported to have effects on both the classical pathway C3-convertase and on the cobra venom factor-induced, alternative pathway convertase. In order to define the mechanism of inhibition, the effect of RA on classical and alternative pathway lysis, C1q binding, the classical pathway convertase, the alternative pathway convertase, membrane attack pathway lysis and the generation of fragments of C3 and C5 during activation, was tested in vitro. The results showed that RA inhibited lysis by the classical pathway more than by the alternative pathway. This effect was dose-dependent with maximum inhibition of classical pathway lysis observed at 2.6 mmoles of RA. There was little effect on C1q binding or on the classical and alternative pathway convertases. However, there was highly significant inhibition of lysis of pre-formed EA43b cells by dilutions of human or rabbit serum in the presence of RA (1 mM); this was accompanied by inhibition of C5a generation. /It was concluded/ that the inhibitory effect of RA involves the C5 convertase. Such inhibition could be advantageous to the host in disorders where the terminal attack sequence plays a role in pathogenesis. PMID:1761351

...Rosmarinic acid (RA), a naturally occurring polyphenol flavonoid, has been reported to inhibit TNF-alpha-induced NF-kappaB activation in human dermal fibroblasts. However, the precise mechanisms of RA have not been well elucidated in TNF-alpha-mediated anti-cancer therapy. In this study, /the authors/ found that RA treatment significantly sensitizes TNF-alpha-induced apoptosis in human leukemia U937 cells through the suppression of nuclear transcription factor-kappaB (NF-kappaB) and reactive oxygen species (ROS). Activation of caspases in response to TNF-alpha was markedly increased by RA treatment. However, pretreatment with the caspase-3 inhibitor, z-DEVD-fmk, was capable of significantly restoring cell viability in response to combined treatment. RA also suppressed NF-kappaB activation through inhibition of phosphorylation and degradation of IkappaBalpha, and nuclear translocation of p50 and p65. This inhibition was correlated with suppression of NF-kappaB-dependent anti-apoptotic proteins (IAP-1, IAP-2, and XIAP). RA treatment also normalized TNF-alpha-induced ROS generation. Additionally, ectopic Bcl-2 expressing U937 reversed combined treatment-induced cell death, cytochrome c release into cytosol, and collapse of mitochondrial potential. These results demonstrated that RA inhibits TNF-alpha-induced ROS generation and NF-kappaB activation, and enhances TNF-alpha-induced apoptosis. PMID:19619938

Rosmarinic acid (RosA) is a hydroxylated compound frequently found in herbal plants and is mostly responsible for anti-inflammatory and antioxidative activity. Previously... RosA inhibited T-cell antigen receptor (TCR)- induced interleukin 2 (IL-2) expression and subsequent T-cell proliferation in vitro. /This study/ investigated /the/ inhibitory mechanism of RosA on TCR signaling, which ultimately activates IL-2 promoter by activating transcription factors, such as nuclear factor of activated T cells (NF-AT) and activating protein-1 (AP-1). Interestingly, RosA inhibited NF-AT activation but not AP-1, suggesting that RosA inhibits Ca+2-dependent signaling pathways only. Signaling events upstream of NF-AT activation, such as the generation of inositol 1,4,5-triphosphate and Ca+2 mobilization, and tyrosine phosphorylation of phospholipase C-gamma 1 (PLC-gamma 1) were strongly inhibited by RosA. Tyrosine phosphorylation of PLC-gamma 1 is largely dependent on 3 kinds of protein tyrosine kinases (PTKs), ie, Lck, ZAP-70, and Itk. /Investigators/ found that RosA efficiently inhibited TCR-induced tyrosine phosphorylation and subsequent activation of Itk but did not inhibit Lck or ZAP-70. ZAP-70-dependent signaling pathways such as the tyrosine phosphorylation of LAT and SLP-76 and serine/threonine phosphorylation of mitogen-activated protein kinases (MAPKs) were intact in the presence of RosA, confirming that RosA suppresses TCR signaling in a ZAP-70-independent manner. .../It is concluded/ that RosA inhibits TCR signaling leading to Ca+2 mobilization and NF-AT activation by blocking membrane-proximal events, specifically, the tyrosine phosphorylation of inducible T cells kinase (Itk) and PLC-gamma 1. PMID:12511421

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RA/Rosmarinic acid showed an interesting antioxidant profile, characterized by reduction in the levels of oxygen and nitrogen free radicals, and inhibition of lipid peroxidation. The compound presented activity on targets related to neurodegenerative diseases, namely the MAO-A and COMT enzymes. Time-dependent inhibition studies on MAO-A, strongly suggested that RA acts as a reversible inhibitor of this target. Cytotoxicity studies on PMN cells indicated that RA does not induce extensive damage to cell membranes in concentrations higher than those displaying the antioxidant profile and enzyme inhibition effects. Molecular docking contributed to understand the binding mode and the main interactions involved in RA, CGA, and CA recognition by MAO-A and COMT enzymes. In addition, insights regarding the different potencies for MAO-A and COMT inhibition displayed by these compounds were retrieved. Taken together, these data can contribute to the rational design of new multifunctional derivatives possessing 3,4-dihydroxycinnamic acid scaffold.[1]

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To summarize, the cytoprotective activity of Rosmarinic acid/RA against UVB radiation may be associated with elimination of ROS, which attenuates oxidative damage to cellular components and induction of apoptosis. Therefore, RA could be used as a therapeutic reagent to safeguard the skin from the deleterious effects of UVB irradiation. These findings may provide an experimental platform for further studies aimed at examining the bioavailability and photo-protective activity of RA, in vitro and in vivo, and determining their underlying mechanisms.[2]

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In summary, our study shows that Rosmarinic acid/RA significantly ameliorates systemic symptoms in a murine DSS-induced colitis model and suppresses expression of pro-inflammatory cytokines and inflammatory mediators through regulation of NF-κB and STAT3 activation. We therefore suggest that RA deserves further consideration as a potential therapeutic for the treatment of inflammatory diseases such as colitis.[3]

C18H16O8

360.3148

360.084

C, 60.00; H, 4.48; O, 35.52

20283-92-5

Rosmarinic acid racemate;537-15-5

5281792

Light yellow to light brown solid powder

1.5±0.1 g/cm3

694.7±55.0 °C at 760 mmHg

171-175 °C(lit.)

254.5±25.0 °C

0.0±2.3 mmHg at 25°C

1.714

1.7

5

8

7

26

519

1

O(C(/C(/[H])=C(\[H])/C1C([H])=C([H])C(=C(C=1[H])O[H])O[H])=O)[C@@]([H])(C(=O)O[H])C([H])([H])C1C([H])=C([H])C(=C(C=1[H])O[H])O[H]

DOUMFZQKYFQNTF-WUTVXBCWSA-N

InChI=1S/C18H16O8/c19-12-4-1-10(7-14(12)21)3-6-17(23)26-16(18(24)25)9-11-2-5-13(20)15(22)8-11/h1-8,16,19-22H,9H2,(H,24,25)/b6-3+/t16-/m1/s1

(2R)-3-(3,4-dihydroxyphenyl)-2-[(E)-3-(3,4-dihydroxyphenyl)prop-2-enoyl]oxypropanoic acid

RM 21A; Labiatic acid; rosmarinic acid; 20283-92-5; rosmarinic acid; 20283-92-5; Rosemary acid; Labiatenic acid; trans-Rosmarinic acid; Rosemaric acid; UNII-MQE6XG29YI; Rosemary acid; Labiatenic acid; (R)-rosmarinic acid; trans-Rosmarinic acid; Rosmarinic acid

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~62.5 mg/mL (~173.46 mM)

Solubility in Formulation 1: ≥ 2.08 mg/mL (5.77 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.08 mg/mL (5.77 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 3: ≥ 2.08 mg/mL (5.77 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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 (Please use freshly prepared in vivo formulations for optimal results.)