- GPR39 (Orphan G protein-coupled receptor 39): Obestatin is the cognate ligand for GPR39. Binding affinity (Kd) to rat jejunum membranes is approximately 4 nM; to CHO cells overexpressing GPR39, the Kd is approximately 1 nM. [2]
- GPR39 (in other studies): Obestatin binds to GPR39 with high affinity, but this binding has been disputed by some subsequent studies. [2]
GPR39 (orphan G protein-coupled receptor) [2] (Kd = 1 nM from saturation binding in CHO cells overexpressing GPR39; Kd = 4 nM from binding to rat jejunal membrane preparations) [2]
Other unknown receptors (biphasic dose-response suggests more than one form of receptor with different sensitivities) [1]

- Jejunal Muscle Contraction: In isolated rat jejunum muscle strips, obestatin (1 μM) decreased spontaneous contractile activity and antagonized the stimulatory effect of ghrelin (1 μM). [2]
- Proliferation of 3T3-L1 Preadipocytes: Obestatin at low doses (10⁻¹¹ M and 10⁻¹³ M) significantly stimulated the proliferation of 3T3-L1 preadipocytes, but showed no effect at higher concentrations (10⁻⁷ M and 10⁻⁹ M). [1]
- Apoptosis of 3T3-L1 Preadipocytes: Obestatin (10⁻⁷ M) significantly inhibited apoptosis induced by serum starvation in 3T3-L1 preadipocytes. [1]
- ERK1/2 Phosphorylation: Obestatin (10⁻⁷ M, 15 min) stimulated ERK1/2 phosphorylation in 3T3-L1 preadipocytes. [1]
- Lipolysis in 3T3-L1 Adipocytes: Obestatin (10⁻⁷ M, 3 h) significantly increased free fatty acid (FFA) release but had no effect on glycerol release after 3, 24, and 48 h of treatment. It had no significant effect on glycerol release at any time point. [1]
- Adenylate Cyclase (cAMP) Activity: In CHO cells overexpressing GPR39, obestatin (0-1000 nM, 15 min at 37°C) stimulated cAMP production in a concentration-dependent manner. Ghrelin and motilin had no effect. [2]
- Serum Response Element (SRE) Activation: In CHO cells cotransfected with GPR39 and an SRE-luciferase reporter construct, obestatin (0-1000 nM) stimulated SRE promoter activity. [2]

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Obestatin's (human) basic structure only reveals a lysine at position 10, suggesting that it is unable to pass across cell membranes [1].

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Obestatin (human) (CAS#: 1081110-72-6) at 10⁻¹¹ M and 10⁻¹³ M significantly stimulated proliferation of 3T3-L1 preadipocytes (MTS assay, 24 h treatment), but showed no effect at higher concentrations (10⁻⁹ M, 10⁻⁷ M, 10⁻⁵ M) [1]. Obestatin (human) (CAS#: 1081110-72-6) (10⁻⁷ M) significantly inhibited serum starvation-induced apoptosis in 3T3-L1 preadipocytes after 48 h (Annexin V-FITC/PI flow cytometry), with less potency than TAT-obestatin [1]. Obestatin (human) (CAS#: 1081110-72-6) (10⁻⁷ M) had no effect on adipogenesis (lipid accumulation by Oil Red O staining, and expression of adiponectin, FABP4, PPARG, GLUT4 by RT-PCR over 9 days) [1]. Obestatin (human) (CAS#: 1081110-72-6) (10⁻⁷ M) had no effect on glycerol release from 3T3-L1 adipocytes after 3, 24, and 48 h treatment, but significantly increased free fatty acid (FFA) release after 3 h treatment (no significant difference at 24 and 48 h) [1]. Obestatin (human) (CAS#: 1081110-72-6) (10⁻⁷ M, 15 min) stimulated ERK1/2 phosphorylation (pERK1/2) in 3T3-L1 preadipocytes as shown by immunoblotting, with stronger effect than TAT-obestatin [1].

- Food Intake (Mice): Intraperitoneal injection of obestatin (1 μmol/kg body weight, 0.1 ml volume) suppressed cumulative food intake in a time- and dose-dependent manner in adult male mice. Intracerebroventricular injection (8 nmol/kg) also decreased food intake. Non-amidated obestatin was less effective. [2]
- Body Weight (Rats): Treatment with obestatin (1 μmol/kg body weight, three times daily, intraperitoneal) suppressed body weight gain in adult male rats over a 12-day period. In contrast, ghrelin (same dose) increased body weight. [2]
- Gastric Emptying (Rats): Obestatin treatment (1 μmol/kg body weight, intraperitoneal) suppressed gastric emptying activity in a dose-dependent manner. [2]
- Serum Ghrelin and Obestatin Levels: Fasting for 48 hours in rats led to a major increase in serum ghrelin levels, which decreased upon refeeding. Serum obestatin levels remained constant across all treatment groups. [2]

---

Intraperitoneal injection of human obestatin (human) decreases food intake in adult male mice in a dose- and time-dependent manner [2].

---

Obestatin (human) (CAS#: 1081110-72-6) (1 μM per kg body weight, intraperitoneal injection) suppressed cumulative food intake in adult male mice in a time- and dose-dependent manner [2]. Intraperitoneal injection at 1 μmol per kg body weight significantly decreased food intake at 1, 3, 5, 7, and 9 h post-injection, with maximal effect at 5 h (approx. 50% reduction) [2]. Lower doses (0.1 and 0.01 μmol per kg) also showed suppression but less pronounced [2]. Intracerebroventricular injection (8 nmol per kg body weight) significantly decreased food intake at 1, 2, 4, and 6 h post-injection [2]. Obestatin (human) (CAS#: 1081110-72-6) (1 μmol per kg body weight, three times daily for 7 days) significantly suppressed body weight gain in adult male rats compared to vehicle control [2]. Obestatin (human) (CAS#: 1081110-72-6) (1 μmol per kg body weight, intraperitoneal) significantly inhibited gastric emptying activity in mice at 2 h post-treatment (approx. 40% reduction), with dose-dependent effect (0.1 and 0.01 μmol per kg also effective) [2]. In vitro, Obestatin (human) (CAS#: 1081110-72-6) (10⁻⁷ M) decreased the contractile activity of rat jejunum muscle strips and antagonized the stimulatory effect of ghrelin (10⁻⁷ M) as measured by isometric force [2]. Obestatin (human) (CAS#: 1081110-72-6) did not increase GH secretion from cultured rat pituitary cells [2].

- Radioligand Binding Assay: Crude plasma membrane preparations from rat jejunum or CHO cells overexpressing GPR39 were incubated with ¹²⁵I-labeled obestatin at varying concentrations (0-100 nM) in binding buffer for 2-3 hours at room temperature. Bound and free tracers were separated by vacuum filtration through glass fiber filters. Non-specific binding was determined in the presence of excess unlabeled obestatin (1 μM). The dissociation constant (Kd) was calculated by Scatchard plot analysis. Hormonal specificity was tested using various competing peptides (ghrelin, motilin, neurotensin, neuromedin U) at concentrations up to 1 μM. [2]
- Adenylyl Cyclase (cAMP) Assay: CHO cells overexpressing GPR39 were seeded and treated with obestatin (0-1000 nM) for 15 minutes at 37°C in the presence of 0.5 mM 3-isobutyl-1-methylxanthine (IBMX). The reaction was stopped by adding 0.1 M HCl. Intracellular cAMP levels were measured using a commercial radioimmunoassay or ELISA kit. [2]

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Binding assay using radioiodinated Obestatin (human) (CAS#: 1081110-72-6) (¹²⁵I-obestatin) with crude plasma membrane preparations from rat jejunum: membranes were incubated with ¹²⁵I-obestatin in the presence or absence of increasing concentrations of unlabeled peptides for 60 min at room temperature, then bound and free ligands were separated by centrifugation; specific binding was determined; Kd = 4 nM was calculated from Scatchard analysis; competition studies showed that unlabeled Obestatin (human) (CAS#: 1081110-72-6) displaced binding, while ghrelin, motilin, neurotensin, and neuromedin U did not; non-amidated obestatin and truncated (des1-10)obestatin showed lower affinity [2].
Binding assay using CHO cells overexpressing GPR39: cells transfected with GPR39 cDNA were incubated with ¹²⁵I-obestatin in binding buffer for 2 h at 4°C, then washed and lysed; saturation binding and Scatchard analysis revealed Kd = 1 nM; competition binding showed that Obestatin (human) (CAS#: 1081110-72-6) competed with high affinity, while ghrelin, motilin, neurotensin, neuromedin U, non-amidated obestatin, and truncated obestatin were ineffective or had lower affinity [2].
cAMP assay: CHO cells overexpressing GPR39 were treated with Obestatin (human) (CAS#: 1081110-72-6) (various concentrations) for 30 min, then cAMP levels were measured by radioimmunoassay; Obestatin (human) (CAS#: 1081110-72-6) stimulated cAMP production in a dose-dependent manner, while ghrelin and motilin had no effect [2].
SRE-luciferase reporter assay: CHO cells cotransfected with GPR39 and a serum response element (SRE)-luciferase construct were treated with Obestatin (human) (CAS#: 1081110-72-6) (100 nM) for 5 h, then luciferase activity was measured; Obestatin (human) (CAS#: 1081110-72-6) activated SRE promoter activity, while ghrelin and motilin did not [2].
Western blotting for ERK1/2 phosphorylation: 3T3-L1 preadipocytes were serum-starved for 5 h, then treated with Obestatin (human) (CAS#: 1081110-72-6) (10⁻⁷ M) for 15 min; cells were lysed in ice-cold RIPA buffer containing protease and phosphatase inhibitors; protein lysates were separated by SDS-PAGE, transferred to nitrocellulose membranes, and probed with phospho-specific anti-ERK1/2 antibodies (1:1000), then with HRP-conjugated secondary antibody (1:2000); blots were reprobed with total ERK1/2 antibody for normalization; signals were visualized using ECL; densitometric analysis showed significant increase in pERK1/2 compared to control [1].

- Proliferation Assay (MTS): 3T3-L1 preadipocytes (5x10³ cells/well) were seeded into 96-well plates, cultured for 24 hours, then incubated overnight in serum-free DMEM. Cells were treated with various concentrations of obestatin (10⁻¹³ to 10⁻⁷ M) or TAT-obestatin for 24 hours. An MTS solution was added for 3 hours, and absorbance was read at 490 nm. [1]
- Apoptosis Assay (Annexin V-FITC/PI): 3T3-L1 preadipocytes were incubated in serum-free DMEM with 0.1% BSA, with or without obestatin (10⁻⁷ M) for 48 hours. Cells were harvested, washed, resuspended in annexin-binding buffer, and stained with Annexin V-FITC and propidium iodide (PI). Stained cells were analyzed by flow cytometry (excitation 488 nm; emission 530 nm and 575 nm). [1]
- Western Blotting: 3T3-L1 preadipocytes were preincubated in serum-free conditions for 5 hours, then treated with obestatin (10⁻⁷ M) or TAT-obestatin for 15 minutes. Cells were lysed in ice-cold RIPA buffer with protease and phosphatase inhibitors. Proteins were separated by SDS-PAGE and transferred to nitrocellulose membranes. Membranes were probed with anti-phospho-ERK1/2 antibody, followed by HRP-conjugated secondary antibody. Signals were visualized using enhanced chemiluminescence (ECL). Total ERK1/2 was used for normalization. [1]
- Lipolysis Assay (Glycerol and FFA): 3T3-L1 adipocytes (differentiated for 9 days) were preincubated in serum-free DMEM for 2 hours, then treated with obestatin (10⁻⁷ M) for 3, 24, or 48 hours. Culture media were collected for measurement of glycerol and free fatty acid (FFA) levels using commercial assay kits (based on colorimetric methods). Glycerol was measured at 550 nm; FFA was measured at 550 nm. [1]
- Radioligand Binding Assay (Cell-based): CHO cells overexpressing GPR39 were seeded, and ¹²⁵I-labeled obestatin binding was performed as described in the Enzyme Assay section. [2]

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Proliferation assay (MTS): 3T3-L1 cells (5×10³ per well) were seeded in 96-well plates, maintained for 24 h in DMEM with 10% FBS, then incubated overnight in serum-free DMEM; cells were treated with various concentrations of Obestatin (human) (CAS#: 1081110-72-6) for 24 h; 20 μL of MTS solution was added to each well, incubated at 37°C for 3 h, and absorbance was read at 490 nm; Obestatin (human) (CAS#: 1081110-72-6) at 10⁻¹¹ M and 10⁻¹³ M significantly increased metabolic activity [1].
Apoptosis assay: 3T3-L1 cells were maintained in serum-free DMEM with 0.1% BSA, and incubated with or without Obestatin (human) (CAS#: 1081110-72-6) (10⁻⁷ M) for 48 h; cells were harvested, washed with PBS, resuspended in annexin-binding buffer, stained with annexin V-FITC and propidium iodide (100 μg/mL) for 15 min at room temperature, then analyzed by flow cytometry (excitation 488 nm, emission 530 nm and 575 nm); apoptotic cells (green fluorescence) were quantified; Obestatin (human) (CAS#: 1081110-72-6) significantly inhibited apoptosis compared to serum-free control [1].
Differentiation assay: 3T3-L1 preadipocytes were grown to confluence (d0), then treated with standard differentiation medium (1.721 mM insulin, 1 mM dexamethasone, 0.5 mM IBMX in DMEM with 10% FBS) for 3 days; then medium replaced with DMEM containing 10% FBS and 1.721 mM insulin for 3 days; then DMEM with 10% FBS for 3 days; Obestatin (human) (CAS#: 1081110-72-6) (10⁻⁷ M) was added at d0, d3, and d6; on day 9, cells were fixed with 10% formalin and stained with Oil Red O for 1 h; lipid droplets visualized by microscopy; stained lipids extracted with isopropanol and absorbance measured at 510 nm; no significant effect on lipid accumulation [1].
RT-PCR: Total RNA was extracted using TRIZOL, reverse transcribed, and real-time PCR performed using SYBR Green; expression of adiponectin, FABP4, PPARG, GLUT4, and GAPDH (internal control) was measured at d0, d2, d6, d8; no significant effect of Obestatin (human) (CAS#: 1081110-72-6) on these marker genes [1].
Lipolysis assay: 3T3-L1 adipocytes (fully differentiated) were maintained in serum-free DMEM for 2 h, then treated with Obestatin (human) (CAS#: 1081110-72-6) (10⁻⁷ M) for 3, 24, or 48 h; medium was collected; glycerol concentration measured using enzymatic assay (glycerol converted to 3-phosphoglycerol by phosphokinase, then to hydrogen peroxide by GPO, chromogenic substrate converted to benzoquinone imine, absorbance at 550 nm); free fatty acid (FFA) measured by copper reagent colorimetric method (absorbance at 550 nm); results expressed relative to cellular triglyceride mass; Obestatin (human) (CAS#: 1081110-72-6) had no effect on glycerol release but significantly increased FFA release at 3 h [1].

- Mouse Food Intake Study (Intraperitoneal): Adult male mice (strain not specified) were injected intraperitoneally with obestatin (1 μmol/kg body weight, 0.1 ml volume) or vehicle (saline) before the dark cycle. Cumulative food intake was measured at 1, 2, 4, and 8 hours post-injection. Non-amidated obestatin (NA-obestatin) and ghrelin were also tested for comparison. Urocortin was used as a positive control. [2]
- Mouse Food Intake Study (Intracerebroventricular): Mice were implanted with intracerebroventricular (icv) cannulas. Obestatin (8 nmol/kg body weight) or MTII (positive control) was injected icv, and food intake was measured at 2, 4, and 6 hours post-injection. [2]
- Rat Body Weight Study: Adult male rats were injected intraperitoneally with obestatin (1 μmol/kg body weight), ghrelin (same dose), or vehicle (saline), three times daily (8:00 AM, 2:00 PM, and 8:00 PM) for 12 days. Body weight was measured daily. [2]
- Rat Gastric Emptying Study: Adult male rats were fasted overnight, then injected intraperitoneally with obestatin (0.3, 1, 3 μmol/kg body weight) or vehicle. Fifteen minutes later, a methylcellulose meal containing phenol red was administered by gavage. After 15 minutes, the stomach was removed, and the amount of phenol red recovered was measured spectrophotometrically to calculate gastric emptying. [2]
- Rat Jejunal Contraction Study: Longitudinal jejunum muscle strips isolated from adult male rats were mounted in organ baths containing oxygenated Krebs buffer at 37°C. Isometric force was measured. Obestatin (1 μM) was added to the bath, and contractile activity was recorded. [2]

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Adult male mice (strain not specified) were fasted overnight, then given intraperitoneal injection of Obestatin (human) (CAS#: 1081110-72-6) at 1 μmol per kg body weight (dissolved in PBS and diluted in sterile saline); food intake was measured at 1, 3, 5, 7, and 9 h post-injection; dose-response study used 0.01, 0.1, and 1 μmol per kg; positive control urocortin; for intracerebroventricular injection, peptides were injected at 8 nmol per kg body weight; MTII used as positive control [2].
Adult male rats were treated intraperitoneally with Obestatin (human) (CAS#: 1081110-72-6) (1 μmol per kg body weight, three times daily) for 7 days; body weight was measured daily; ghrelin (1 μmol per kg) and vehicle served as controls; serum leptin levels were also measured [2].
Gastric emptying assay: Adult male mice were fasted overnight, then intraperitoneally injected with Obestatin (human) (CAS#: 1081110-72-6) (0.01, 0.1, or 1 μmol per kg); 30 min later, a test meal (phenol red in methylcellulose) was administered orally; after 15 min, mice were sacrificed, stomachs removed, and phenol red recovered and measured spectrophotometrically to calculate gastric emptying rate [2].
Jejunum muscle strip contraction: Adult male rats were sacrificed, jejunum segments (2 cm) were mounted in organ baths containing Krebs solution at 37°C, gassed with 95% O₂/5% CO₂; isometric tension was recorded; after equilibration, Obestatin (human) (CAS#: 1081110-72-6) (10⁻⁷ M) or ghrelin (10⁻⁷ M) was added; contractile activity was measured as percentage of maximal response; Obestatin (human) (CAS#: 1081110-72-6) decreased basal contraction and antagonized ghrelin-induced stimulation [2].

- Serum Levels: Obestatin serum levels in rats were measured by radioimmunoassay. Fasting (48 hours) did not significantly alter serum obestatin levels, whereas ghrelin levels increased dramatically. [2]
- Tissue Distribution: Obestatin immunoreactivity was detected in stomach extracts, with two peaks (2.6 kD and 1.5 kD) on gel permeation chromatography, representing full-length obestatin and a C-terminal fragment. [2]

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- Cytotoxicity in Cell Lines: Obestatin showed no obvious cytotoxicity in 3T3-L1, C2C12, and PK15 cell lines at concentrations ranging from 0.001 to 100 μM. Only at the highest concentration (100 μM) in C2C12 cells was a ~20% decrease in cell viability observed. [1]
- General Safety: No acute toxicity or adverse effects on animal behavior were reported in the in vivo studies at the administered doses. [1][2]

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[1]. Effect of TAT-obestatin on proliferation, differentiation, apoptosis and lipolysis in 3T3-L1 preadipocytes. J Pept Sci. 2013 Nov;19(11):684-91.
[2]. Obestatin, a peptide encoded by the ghrelin gene, opposes ghrelin's effects on food intake. Science. 2005 Nov 11;310(5750):996-9.

- Discovery and Origin: Obestatin is a peptide hormone encoded by the ghrelin gene. It is derived from the C-terminal region of the preproghrelin precursor protein and requires C-terminal amidation for full biological activity. [2]
- Mechanism of Action (Anorexigenic): Obestatin acts as an appetite-suppressing hormone opposing ghrelin. It binds to the orphan receptor GPR39, leading to activation of intracellular signaling pathways (cAMP, SRE), which in turn inhibits food intake, gastric emptying, and jejunal motility. [2]
- Biphasic Effects: Obestatin exhibits a U-shaped or biphasic dose-response curve in some assays (e.g., proliferation, insulin secretion), suggesting the possible existence of multiple receptor subtypes with different ligand sensitivities. [1]
- Structure-Activity Relationship: C-terminal amidation is critical for obestatin's bioactivity, as non-amidated obestatin (NA-obestatin) was less effective in binding and functional assays. Truncated (des1-10) obestatin also showed lower binding affinity. [2]
- Controversy: The initial finding that obestatin is the cognate ligand for GPR39 has been disputed by subsequent studies that failed to reproduce the binding or signaling activation. The receptor for obestatin remains a subject of investigation. [2]

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Obestatin (human) (CAS#: 1081110-72-6) is a ghrelin gene-encoded peptide that opposes ghrelin's effects on food intake and body weight regulation [2]. It is amidated at the C-terminus, which is critical for its bioactivity; non-amidated obestatin is less effective [2]. The peptide is derived from posttranslational processing of preproghrelin; fasting increases serum ghrelin but not obestatin levels, suggesting differential secretion [2]. Obestatin (human) (CAS#: 1081110-72-6) is expressed in stomach, and its immunoreactive forms include a 2.6 kD mature peptide and a 1.5 kD fragment representing the last 13 residues [2]. GPR39 mRNA is expressed in jejunum, duodenum, stomach, pituitary, ileum, liver, hypothalamus, and other tissues [2]. The discovery of two opposing hormones (ghrelin and obestatin) from the same proprotein highlights the importance of posttranslational regulatory mechanisms in energy homeostasis [2]. In 3T3-L1 cells, Obestatin (human) (CAS#: 1081110-72-6) may exert autocrine/paracrine regulation [1]. The biphasic dose-response effect (mitogenic at low concentrations, no effect at high) may explain difficulties in reproducing some obestatin effects [1].

C116H176N32O33

2546.83326625824

2545.307

1081110-72-6

Obestatin(human) TFA

91826105

H-DL-Phe-DL-Asn-DL-Ala-DL-Pro-DL-Phe-DL-Asp-DL-Val-Gly-DL-xiIle-DL-Lys-DL-Leu-DL-Ser-Gly-DL-Val-DL-Gln-DL-Tyr-DL-Gln-DL-Gln-DL-His-DL-Ser-DL-Gln-DL-Ala-DL-Leu-NH2
DL-phenylalanyl-DL-asparagyl-DL-alanyl-DL-prolyl-DL-phenylalanyl-DL-alpha-aspartyl-DL-valyl-glycyl-DL-isoleucyl-DL-lysyl-DL-leucyl-DL-seryl-glycyl-DL-valyl-DL-glutaminyl-DL-tyrosyl-DL-glutaminyl-DL-glutaminyl-DL-histidyl-DL-seryl-DL-glutaminyl-DL-alanyl-DL-leucinamide

FNAPFDVGIKLSGVQYQQHSQAL-NH2

White to off-white solid powder

1.3±0.1 g/cm3

2616.2±65.0 °C at 760 mmHg

1536.0±34.3 °C

0.0±0.3 mmHg at 25°C

1.582

-3.12

34

36

82

181

5750

22

O=C([C@@H]1CCCN1C([C@H](C)NC([C@H](CC(N)=O)NC([C@H](CC1C=CC=CC=1)N)=O)=O)=O)N[C@H](C(N[C@H](C(N[C@H](C(NCC(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(NCC(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@@H](CO)C(N[C@H](C(N[C@@H](C)C(N[C@H](C(N)=O)CC(C)C)=O)=O)CCC(N)=O)=O)=O)CC1=CNC=N1)=O)CCC(N)=O)=O)CCC(N)=O)=O)CC1C=CC(=CC=1)O)=O)CCC(N)=O)=O)C(C)C)=O)=O)CO)=O)CC(C)C)=O)CCCCN)=O)[C@@H](C)CC)=O)=O)C(C)C)=O)CC(=O)O)=O)CC1C=CC=CC=1

IXQOGPZNKNSCJR-QQDMDDJXSA-N

InChI=1S/C116H176N32O33/c1-13-61(10)95(146-91(158)53-127-113(178)93(59(6)7)147-110(175)81(50-92(159)160)141-108(173)78(46-65-25-18-15-19-26-65)142-112(177)84-28-22-42-148(84)116(181)63(12)130-105(170)80(49-89(123)156)137-98(163)69(118)45-64-23-16-14-17-24-64)115(180)134-70(27-20-21-41-117)101(166)138-76(44-58(4)5)106(171)143-82(54-149)99(164)126-52-90(157)145-94(60(8)9)114(179)135-74(36-40-88(122)155)104(169)139-77(47-66-29-31-68(151)32-30-66)107(172)132-72(34-38-86(120)153)102(167)131-73(35-39-87(121)154)103(168)140-79(48-67-51-125-56-128-67)109(174)144-83(55-150)111(176)133-71(33-37-85(119)152)100(165)129-62(11)97(162)136-75(96(124)161)43-57(2)3/h14-19,23-26,29-32,51,56-63,69-84,93-95,149-151H,13,20-22,27-28,33-50,52-55,117-118H2,1-12H3,(H2,119,152)(H2,120,153)(H2,121,154)(H2,122,155)(H2,123,156)(H2,124,161)(H,125,128)(H,126,164)(H,127,178)(H,129,165)(H,130,170)(H,131,167)(H,132,172)(H,133,176)(H,134,180)(H,135,179)(H,136,162)(H,137,163)(H,138,166)(H,139,169)(H,140,168)(H,141,173)(H,142,177)(H,143,171)(H,144,174)(H,145,157)(H,146,158)(H,147,175)(H,159,160)/t61-,62-,63-,69-,70-,71-,72-,73-,74-,75-,76-,77-,78-,79-,80-,81-,82-,83-,84-,93-,94-,95-/m0/s1

(3S)-4-[[(2S)-1-[[2-[[(2S,3S)-1-[[(2S)-6-amino-1-[[(2S)-1-[[(2S)-1-[[2-[[(2S)-1-[[(2S)-5-amino-1-[[(2S)-1-[[(2S)-5-amino-1-[[(2S)-5-amino-1-[[(2S)-1-[[(2S)-1-[[(2S)-5-amino-1-[[(2S)-1-[[(2S)-1-amino-4-methyl-1-oxopentan-2-yl]amino]-1-oxopropan-2-yl]amino]-1,5-dioxopentan-2-yl]amino]-3-hydroxy-1-oxopropan-2-yl]amino]-3-(1H-imidazol-4-yl)-1-oxopropan-2-yl]amino]-1,5-dioxopentan-2-yl]amino]-1,5-dioxopentan-2-yl]amino]-3-(4-hydroxyphenyl)-1-oxopropan-2-yl]amino]-1,5-dioxopentan-2-yl]amino]-3-methyl-1-oxobutan-2-yl]amino]-2-oxoethyl]amino]-3-hydroxy-1-oxopropan-2-yl]amino]-4-methyl-1-oxopentan-2-yl]amino]-1-oxohexan-2-yl]amino]-3-methyl-1-oxopentan-2-yl]amino]-2-oxoethyl]amino]-3-methyl-1-oxobutan-2-yl]amino]-3-[[(2S)-2-[[(2S)-1-[(2S)-2-[[(2S)-4-amino-2-[[(2S)-2-amino-3-phenylpropanoyl]amino]-4-oxobutanoyl]amino]propanoyl]pyrrolidine-2-carbonyl]amino]-3-phenylpropanoyl]amino]-4-oxobutanoic acid

Obestatin (human); 1081110-72-6; Obestatin human; Obestatin (human) trifluoroacetate salt; PGH-3890-PI;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture and light.

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

DMSO : ~1.96 mg/mL (~0.77 mM)

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.)