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Jie Liu - One of the best experts on this subject based on the ideXlab platform.
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Oleanolic Acid nanosuspensions preparation in vitro characterization and enhanced hepatoprotective effect
Journal of Pharmacy and Pharmacology, 2010Co-Authors: Yajun Chen, Jie Liu, Xiangliang Yang, Xiaoling ZhaoAbstract:Oleanolic Acid is a naturally derived triterpene used clinically in the treatment of hepatitis in China, but its poor solubility often leads to poor bioavailability. In the present study, Oleanolic Acid nanosuspensions were prepared by the nanoprecipitation method and then systematically characterized. The average particle size of the obtained nanosuspensions was 284.9 nm, with a polydispersity index of 0.216. Transmission electron microscopy and atomic force microscopy showed that the drug existed as spherical or near-spherical nanoparticles in the nanosuspensions. Differential scanning calorimetry and X-ray diffraction studies indicated that Oleanolic Acid was present in an amorphous state in the lyophilized nanosuspensions. At 25 degrees C, the saturation solubility of Oleanolic Acid was increased by about 6 times after nanoation (25.72 microg mL(-1) vs 4.37 microg mL(-1)). In the in-vitro drug release experiments, the lyophilized nanosuspensions showed a faster drug dissolution rate than that of the coarse drug powder (approx. 90% vs 15% during the first 20 min), and nearly 95% of the Oleanolic Acid was released by 120 min. As evidenced by the lower serum alanine aminotransferase activity and liver malondialdehyde content, pre-treatment with Oleanolic Acid nanosuspensions significantly enhanced the hepatoprotective effect of Oleanolic Acid against carbon tetrachloride-induced liver injury.
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Review article Pharmacology of Oleanolic Acid and ursolic Acid
Journal of Ethnopharmacology, 1995Co-Authors: Jie LiuAbstract:Oleanolic Acid and ursolic Acid are triterpenoid compounds that exist widely in food, medicinal herbs and other plants. This review summarizes the pharmacological studies on these two triterpenoids. Both Oleanolic Acid and ursolic Acid are effective in protecting against chemically induced liver injury in laboratory animals. Oleanolic Acid has been marketed in China as an oral drug for human liver disorders. The mechanism of hepatoprotection by these two compounds may involve the inhibition of toxicant activation and the enhancement of the body defense systems. Oleanolic Acid and ursolic Acid have also been long-recognized to have antiinflammatory and antihyperlipidemic properties in laboratory animals, and more research is warranted to develop a therapy for patients. Recently, both compounds have been noted for their antitumor-promotion effects, which are stimulating additional research in this field. Oleanolic Acid and ursolic Acid are relatively non-toxic, and have been used in cosmetics and health products. The possible mechanisms for the pharmacological effects and the prospects for these two compounds are discussed.
Gao Xiao-li - One of the best experts on this subject based on the ideXlab platform.
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Study on small intestinal absorption of Oleanolic Acid new proliposome in rat
Journal of Xinjiang Medical University, 2007Co-Authors: Gao Xiao-liAbstract:Objective: To study the small intestinal absorption of Oleanolic Acid new proliposome in rat. Method: The Oleanolic Acid proliposome was made by a new method, and then The isolated small intestinal absorption method was developed, finally the concentration of Oleanolic Acid was determined by HPLC. The area under curve (AUC) of concentration-time curve was obtained. Results: The AUC in serosal fluid of proliposome was much larger than that of control group. Conclusion: The prepared proliposome can improve the small intestinal absorption of Oleanolic Acid.
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Study on Preparation of a New Oleanolic Acid Proliposomes and Its Properties
The Chinese Pharmaceutical Journal, 2007Co-Authors: Gao Xiao-liAbstract:OBJECTIVE To prepare a new kind of Oleanolic Acid proliposomes and develop a new formulation of Oleanolic Acid,and to investigate its properties.METHODS A new kind of proliposome preparation method was used to prepare the Oleanolic Acid proliposomes,and then the properties of the liposomes,including the surface morphology,the size,the entrapment efficiency and the absorption in vitro,were studied after the proliposomes were changed into the liposomes. RESULTS The study proved the Oleanolic Acid was trapped into the liposomes.The particle size of the liposomes was small and the size distribution was uniformed,the entrapment efficiency was(85.65±7.96)%. Furthermore, the entrapment efficiency was related to the pH of the liposome solution and the proportion of the drug and the phosphatide(that is P/D). When pH was increased,the entrapment efficiency was improved. When the proportion of the P/D was increased from 5∶1 to 10∶1,the entrapement efficiency was increased too. The intestinal absorption result proved that the liposomes contributed to the drug absorption,compared with the control group.CONCLUSION The Oleanolic Acid can be trapped into the liposomes according to this method. And the entrapment efficiency and the absorption of the liposomes are high. The study will be the first step of the preparation of a new Oleanolic Acid liposomes.
Allen Volchuk - One of the best experts on this subject based on the ideXlab platform.
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Oleanolic Acid enhances insulin secretion in pancreatic β cells
FEBS Letters, 2008Co-Authors: Tracy Teodoro, Liling Zhang, Todd Alexander, Jessica T.y. Yue, Mladen Vranic, Allen VolchukAbstract:We investigated the effect of Oleanolic Acid, a plant-derived triterpenoid, on insulin secretion and content in pancreatic beta-cells and rat islets. Oleanolic Acid significantly enhanced insulin secretion at basal and stimulatory glucose concentrations in INS-1 832/13 cells and enhanced acute glucose-stimulated insulin secretion in isolated rat islets. In the cell line the effects of Oleanolic Acid on insulin secretion were comparable to that of the sulfonylurea tolbutamide at basal glucose levels and with the incretin mimetic Exendin-4 under glucose-stimulated conditions, yet neither Ca(2+) nor cAMP rose in response to Oleanolic Acid. Chronic treatment with Oleanolic Acid increased total cellular insulin protein and mRNA levels. These effects may contribute to the anti-diabetic properties of this natural product.
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Oleanolic Acid enhances insulin secretion in pancreatic β‐cells
FEBS letters, 2008Co-Authors: Tracy Teodoro, Liling Zhang, Todd Alexander, Jessica T.y. Yue, Mladen Vranic, Allen VolchukAbstract:We investigated the effect of Oleanolic Acid, a plant-derived triterpenoid, on insulin secretion and content in pancreatic beta-cells and rat islets. Oleanolic Acid significantly enhanced insulin secretion at basal and stimulatory glucose concentrations in INS-1 832/13 cells and enhanced acute glucose-stimulated insulin secretion in isolated rat islets. In the cell line the effects of Oleanolic Acid on insulin secretion were comparable to that of the sulfonylurea tolbutamide at basal glucose levels and with the incretin mimetic Exendin-4 under glucose-stimulated conditions, yet neither Ca(2+) nor cAMP rose in response to Oleanolic Acid. Chronic treatment with Oleanolic Acid increased total cellular insulin protein and mRNA levels. These effects may contribute to the anti-diabetic properties of this natural product.
Liu Jie - One of the best experts on this subject based on the ideXlab platform.
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Pharmacology of Oleanolic Acid and ursolic Acid
Journal of Ethnopharmacology, 1995Co-Authors: Liu JieAbstract:Oleanolic Acid and ursolic Acid are triterpenoid compounds that exist widely in food, medicinal herbs and other plants. This review summarizes the pharmacological studies on these two triterpenoids. Both Oleanolic Acid and ursolic Acid are effective in protecting against chemically induced liver injury in laboratory animals. Oleanolic Acid has been marketed in China as an oral drug for human liver disorders. The mechanism of hepatoprotection by these two compounds may involve the inhibition of toxicant activation and the enhancement of the body defense systems. Oleanolic Acid and ursolic Acid have also been long-recognized to have antiinflammatory and antihyperlipidemic properties in laboratory animals, and more research is warranted to develop a therapy for patients. Recently, both compounds have been noted for their antitumor-promotion effects, which are stimulating additional research in this field. Oleanolic Acid and ursolic Acid are relatively non-toxic, and have been used in cosmetics and health products. The possible mechanisms for the pharmacological effects and the prospects for these two compounds are discussed.
Hyeong-kyu Lee - One of the best experts on this subject based on the ideXlab platform.
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Anticomplement activities of Oleanolic Acid monodesmosides and bisdesmosides isolated from Tiarella polyphylla.
Archives of pharmacal research, 1999Co-Authors: Si Hyung Park, Keun Young Jung, Im Seon Lee, Kyung Seop Ahn, Jae Gil Kim, Jung Joon Lee, Hyeong-kyu LeeAbstract:Seven known Oleanolic Acid glycosides (1–7) were isolated from the MeOH extract ofTiarella polyphylla. The structures were identified to be 3-O-(β-D-glucopyranosyl) Oleanolic Acid (1), 3-O-[β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl] Oleanolic Acid (2), 3-O-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl] Oleanolic Acid (3), 3-O-[β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl] Oleanolic Acid 28-O-β-D-glucopyranosyl ester (4), 3-O-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl] lleanolic Acid 28-O-β-D-glucopyranosyl ester (5), 3-O-[a-L-rhamnopyranosyl-(1→3)-β-D-glucuronopyranosyl] Oleanolic Acid (6), and 3-O-[α-L-rhamnopyranosyl-(1→3)-β-D-glucuronopyranosyl] Oleanolic Acid 28-O-β-D-glucopyranosyl ester (7) on the basis of physicochemical and spectral data. These triterpene glycosides were tested for the anticomplement activity and hemolytic activity. Bisdesmosidic saponins,4, 5, and7, showed anticomplement activity; in contrast, monodesmosidic saponins,1–3, and6, showed direct hemolytic activity. Methyl esterified monodesmosidic saponins showed anticomplement activity at a low concentration and hemolytic activity at a high concentration.
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Anticomplement activities of Oleanolic Acid monodesmosides and bisdesmosides isolated from tiarella polyphylla
Pharmaceutical Society of Korea, 1999Co-Authors: Si Hyung Park, Keun Young Jung, Im Seon Lee, Kyung Seop Ahn, Jae Gil Kim, Jung Joon Lee, Hyeong-kyu LeeAbstract:Seven known Oleanolic Acid glycosides (1-7) were isolated from the MeOH extract of Tiarella polyphylla. The structures were identified to be 3-O-(β-D-glucopyranosyl) Oleanolic Acid (1), 3-O-[β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl] Oleanolic Acid (2), 3-O-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl] Oleanolic Acid (3), 3-O-[β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl] Oleanolic Acid 28-O-β-D-glucopyranosyl ester (4), 3-O-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl] Oleanolic Acid 28-O-β-D-glucopyranosyl ester (5), 3-O-[a-L-rhamnopyranosyl-(1→3)-β-D-glucuronopyranosyl] Oleanolic Acid (6), and 3-O-[α-L-rhamnopyranosyl-(1→3)-β-D-glucuronopyranosyl] Oleanolic Acid 28-O-β-D-glucopyranosyl ester (7) on the basis of physicochemical and spectral data. These triterpene glycosides were tested for the anticomplement activity and hemolytic activity. Bisdesmosidic saponins, 4, 5, and 7, showed anticomplement activityin contrast, monodesmosidic saponins, 1-3, and 6, showed direct hemolytic activity. Methyl esterified monodesmosidic saponins showed anticomplement activity at a low concentration and hemolytic activity at a high concentration.ope
