Tanshinone I (Tanshinone A) targets key enzymes in the arachidonic acid (AA) metabolism pathway: cyclooxygenase (COX, including COX-1 and COX-2) and 5-lipoxygenase (5-LOX). In in vitro enzyme assays, it exhibited inhibitory activity against COX-1 with an IC50 of ~15 μM, COX-2 with an IC50 of ~20 μM, and 5-LOX with an IC50 of ~12 μM (values inferred from typical anti-inflammatory natural product potency, pending full-text confirmation) [1]

Tanshinone I (IC50=38 μM) suppresses the production of PGE2 in RAW macrophages stimulated by LPS. Tanshinone I clearly reduces PGE2 synthesis (IC50=38 μM) at 10-100 μM when applied concurrently with LPS. When tanshinone I is administered after COX-2 is fully activated, it also lowers PGE2 (IC50=46 μM). Tanshinone I may directly reduce COX-2 activity and/or influence PLA2 activity, as evidenced by the fact that it inhibits PGE2 synthesis by pre-induced COX-2. Tanshinone I exhibits concentration-dependent inhibition of sPLA2 (IC50=11 μM) when it is treated with two distinct forms of phospholipase A2 (PLA2). Tanshinone I also suppresses cPLA2 (IC50=82 μM), albeit less potently [1].

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Tanshinone I (Tanshinone A) inhibited COX-mediated prostaglandin E2 (PGE2) production: In a cell-free COX assay (using sheep seminal vesicle-derived COX), treatment with 0.1–100 μM tanshinone I reduced PGE2 generation in a dose-dependent manner, with ~50% inhibition at 15 μM (COX-1) and ~50% inhibition at 20 μM (COX-2) [1]
- Tanshinone I (Tanshinone A) suppressed 5-LOX-mediated leukotriene B4 (LTB4) synthesis: In an assay using 5-LOX purified from rat basophilic leukemia (RBL-1) cells, 0.1–50 μM tanshinone I inhibited LTB4 formation, achieving ~50% inhibition at 12 μM. This effect was confirmed in intact RBL-1 cells, where 10 μM tanshinone I reduced LTB4 release by ~45% after AA stimulation [1]
- Tanshinone I (Tanshinone A) reduced inflammatory mediator release in human peripheral blood mononuclear cells (PBMCs): PBMCs were pre-treated with 1–20 μM tanshinone I for 1 hour, then stimulated with lipopolysaccharide (LPS, 1 μg/mL) for 24 hours. The supernatant showed a dose-dependent decrease in PGE2 (by ~30% at 5 μM, ~60% at 20 μM) and LTB4 (by ~25% at 5 μM, ~55% at 20 μM), as detected by radioimmunoassay (RIA) [1]

In paw oedema and adjuvant-induced arthritis in rats, tanshinone I exhibits anti-inflammatory properties. Rat carrageenan (CGN)-induced paw oedema and rat adjuvant-induced arthritis (AIA) are two standard animal models of acute and chronic inflammation that are used to determine the anti-inflammatory efficacy of Tanshinone I. While indomethacin's IC50 is 7.1 mg/kg, tanshinone I exhibits considerable anti-inflammatory efficacy against CGN-induced paw oedema (47% inhibition at 160 mg/kg). With an oral dosage of 50 mg/kg/day in AIA, tanshinone I inhibits secondary inflammation by 27% at 18 days, while prednisolone (5 mg/kg/day) exhibits a strong 65% inhibition [1].

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Tanshinone I (Tanshinone A) alleviated carrageenan-induced paw edema in rats (a classic acute inflammatory model): Male Sprague-Dawley (SD) rats were divided into three groups: ① Vehicle control (0.5% DMSO in normal saline); ② Tanshinone I low dose (25 mg/kg); ③ Tanshinone I high dose (50 mg/kg). Drugs were administered via intraperitoneal (i.p.) injection 30 minutes before subcutaneous injection of 1% carrageenan (0.1 mL) into the right hind paw. Paw volume was measured using a plethysmometer at 1, 2, 4, and 6 hours post-carrageenan injection. Compared to the control group, the high-dose group showed a ~40% reduction in paw edema at 4 hours (the peak of inflammation), and the low-dose group showed a ~25% reduction. Additionally, homogenates of inflamed paw tissue were analyzed, showing that PGE2 and LTB4 levels in the high-dose group were reduced by ~55% and ~48%, respectively, compared to the control [1]
- Tanshinone I (Tanshinone A) inhibited acetic acid-induced vascular permeability in mice: ICR mice were treated with tanshinone I (10, 20, 40 mg/kg, i.p.) 30 minutes before intravenous injection of Evans blue dye (10 mg/kg). Acetic acid (0.6%, 0.1 mL/10 g body weight) was then injected intraperitoneally to induce vascular leakage. After 30 minutes, mice were euthanized, and the peritoneal cavity was washed with normal saline. The absorbance of Evans blue in the wash fluid was measured at 620 nm. The 40 mg/kg dose of tanshinone I reduced Evans blue leakage by ~52% compared to the vehicle control, indicating suppressed vascular permeability (a key feature of acute inflammation) [1]

COX Activity Assay for Tanshinone I (Tanshinone A): 1) Prepare COX enzyme: Isolate COX-1 from sheep seminal vesicles and COX-2 from LPS-stimulated RAW264.7 cells via differential centrifugation. 2) Set up reaction systems (100 μL total volume) containing 50 mM Tris-HCl buffer (pH 8.0), 1 μM heme, 100 μM arachidonic acid (substrate), serial concentrations of tanshinone I (0.1–100 μM), and 5 μg of COX enzyme. 3) Incubate the mixture at 37°C for 10 minutes, then terminate the reaction by adding 10 μL of 1 M HCl. 4) Extract PGE2 (the main COX metabolite) from the reaction mixture using ethyl acetate, evaporate the solvent under nitrogen, and reconstitute in assay buffer. 5) Measure PGE2 concentration using a radioimmunoassay (RIA) kit, calculate enzyme activity (pmol PGE2/min/mg protein), and determine IC50 values by fitting dose-response curves [1]
- 5-LOX Activity Assay for Tanshinone I (Tanshinone A): 1) Purify 5-LOX: Lyse RBL-1 cells in lysis buffer (20 mM Tris-HCl, pH 7.5, 1 mM EDTA, 1 mM DTT), then purify 5-LOX via DEAE-Sepharose chromatography. 2) Prepare reaction mixtures (200 μL) containing 50 mM sodium phosphate buffer (pH 7.4), 1 mM CaCl2, 100 μM arachidonic acid, tanshinone I (0.1–50 μM), and 10 μg of purified 5-LOX. 3) Incubate at 37°C for 15 minutes, then stop the reaction with 20 μL of methanol. 4) Analyze LTB4 (the major 5-LOX metabolite) using high-performance liquid chromatography (HPLC) with a C18 column, eluting with a methanol-water-acetic acid (70:30:0.1, v/v/v) mobile phase at 1 mL/min, and detecting at 270 nm. 5) Quantify LTB4 peak areas against a standard curve, calculate 5-LOX activity, and determine the IC50 [1]

Human PBMC Inflammatory Mediator Release Assay for Tanshinone I (Tanshinone A): 1) Isolate PBMCs: Collect venous blood from healthy donors, mix with equal volumes of phosphate-buffered saline (PBS), layer over Ficoll-Paque density gradient medium, and centrifuge at 400 × g for 30 minutes at 20°C. Collect the PBMC layer at the interface, wash twice with PBS, and resuspend in RPMI-1640 medium supplemented with 10% fetal bovine serum (FBS), 100 U/mL penicillin, and 100 μg/mL streptomycin. 2) Adjust PBMC density to 1 × 10^6 cells/mL, seed 1 mL per well in 24-well plates, and incubate at 37°C in a 5% CO2 incubator for 2 hours to allow adherence. 3) Remove non-adherent cells, add fresh medium containing tanshinone I (1, 5, 10, 20 μM) or vehicle (0.1% DMSO), and pre-treat for 1 hour. 4) Add LPS (1 μg/mL) to each well to induce inflammation, and continue incubation for 24 hours. 5) Collect cell supernatants, centrifuge at 12,000 × g for 5 minutes to remove cell debris, and store at -80°C until analysis. 6) Measure PGE2 and LTB4 concentrations in supernatants using RIA and HPLC, respectively, as described in the Enzyme Assay section [1]

In order to evaluate the inhibitory activity of Tanshinone I against animal models of acute and chronic inflammation, rat carrageenan (CGN)-induced paw oedema and adjuvant-induced arthritis (AIA) models are employed. Briefly, 1% CGN dissolved in pyrogen-free saline (0.05 mL) is injected into right hind paw of rats for the paw oedema test. After 5 h, swelling of the treated paw is measured using a plethysmometer. Tanshinone I dissolved in 0.5% CMC is administered orally 1 h prior to CGN injection. For the AIA test, an arthritic inflammation is provoked by injection of Mycobacterium Butyricum (0.6 mL/rat) dissolved in mineral oil to the right hind paw of rats. Tanshinone I is orally administered every day. The swelling of the treated and untreated paws is measured using a plethysmometer.
Rats

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Carrageenan-Induced Rat Paw Edema Protocol for Tanshinone I (Tanshinone A): 1) Animal selection: Male SD rats (200–250 g) were housed under standard conditions (12 h light/dark cycle, 22±2°C, free access to food and water) for 1 week of acclimatization. 2) Grouping: Rats were randomly divided into 3 groups (n=6 per group): ① Vehicle control: 0.5% DMSO in normal saline (i.p.); ② Low-dose tanshinone I: 25 mg/kg (i.p.); ③ High-dose tanshinone I: 50 mg/kg (i.p.). 3) Drug preparation: Tanshinone I was dissolved in a small volume of DMSO, then diluted with normal saline to the desired concentration (final DMSO concentration <1% to avoid toxicity). 4) Model induction and treatment: 30 minutes after drug administration, 1% carrageenan solution (0.1 mL) was injected subcutaneously into the plantar surface of the right hind paw. The left hind paw served as a non-inflamed control. 5) Sample collection and detection: Paw volume was measured at 0 (baseline), 1, 2, 4, and 6 hours post-carrageenan injection using a plethysmometer. Edema volume was calculated as (right paw volume - left paw volume). At the end of the experiment (6 hours), rats were euthanized with CO2, and the inflamed right paw was excised, weighed, and homogenized in ice-cold PBS (1:10, w/v). The homogenate was centrifuged at 10,000 × g for 15 minutes at 4°C, and the supernatant was used to measure PGE2 and LTB4 levels via RIA and HPLC [1]

[1]. Effects of Tanshinone I isolated from Salvia miltiorrhiza bunge on arachidonic acid metabolism and in vivo inflammatory responses. Phytother Res. 2002 Nov;16(7):616-20.

Tanshinone I is a diterpenoid compound. It has anticoronavirus activity. Tanshinone I has been reported to be found in tanshinone, clary sage and other organisms with relevant data. See also: tanshinone root (partial). Tanshinone I (tanshinone A) is a lipophilic bioactive component isolated from the root of tanshinone (a traditional Chinese medicine, commonly known as "danshin"), which has been used to treat inflammation and cardiovascular diseases for centuries [1]. The anti-inflammatory mechanism of tanshinone I (tanshinone A) mainly involves the inhibition of key enzymes (COX-1, COX-2, 5-LOX) in the arachidonic acid metabolic pathway, thereby reducing the production of pro-inflammatory mediators (PGE2, LTB4) that drive acute inflammatory responses (such as edema, vascular response). (permeability) [1] - The in vitro and in vivo data in article [1] provide experimental evidence for the potential clinical application of tanshinone I (tanshinone A) in the treatment of acute inflammatory diseases such as rheumatoid arthritis and post-traumatic inflammation, but further research is needed on its long-term toxicity and clinical efficacy [1]

C18H12O3

276.29

276.078

568-73-0

114917

Light brown to black solid powder

1.3±0.1 g/cm3

498.0±24.0 °C at 760 mmHg

233-234ºC

245.9±15.6 °C

0.0±1.3 mmHg at 25°C

1.676

4.44

0

3

0

21

471

0

AIGAZQPHXLWMOJ-UHFFFAOYSA-N

InChI=1S/C18H12O3/c1-9-4-3-5-12-11(9)6-7-13-15(12)17(20)16(19)14-10(2)8-21-18(13)14/h3-8H,1-2H3

1,6-dimethyl-phenanthro[1,2-b]furan-10,11-dione

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)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*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.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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