ABSTRACT
Gypenosides, structurally analogous to ginsenosides and derived from a sustainable source, are recognized as the principal active compounds found in Gynostemma pentaphyllum, a Chinese medicinal plant used in the treatment of the metabolic syndrome. By bioactive tracking isolation of the plants collected from different regions across China, we obtained four new gypenosides (1-4), together with nine known gypenosides (5-13), from the methanol extract of the plant. The structures of new gypenosides were elucidated by one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) spectra, complemented by chemical degradation experiments. Through comprehensive evaluation involving COL1A1 promoter assays and PP2Cα activity assays, we established a definitive structure-activity relationship for these dammarane-type triterpenoids, affirming the indispensability of the C-3 saccharide chain and C-17 lactone ring in effectively impeding extracellular matrix (ECM) deposition within hepatic stellate cells. Further in vivo study on the CCl4-induced liver damage mouse model corroborated that compound 5 significantly ameliorated the process of hepatic fibrosis by oral administration. These results underscore the potential of dammarane-type triterpenoids as prospective anti-fibrotic leads and highlight their prevalence as key molecular frameworks in the therapeutic intervention of chronic hepatic disorders.
Subject(s)
Animals , Mice , Gynostemma , Liver Cirrhosis/drug therapy , Triterpenes/pharmacology , Ginsenosides , Extracellular Matrix , DammaranesABSTRACT
Blood-brain barrier (BBB) damage after ischemia significantly influences stroke outcome. Compound LFHP-1c was previously discovered with neuroprotective role in stroke model, but its mechanism of action on protection of BBB disruption after stroke remains unknown. Here, we show that LFHP-1c, as a direct PGAM5 inhibitor, prevented BBB disruption after transient middle cerebral artery occlusion (tMCAO) in rats. Mechanistically, LFHP-1c binding with endothelial PGAM5 not only inhibited the PGAM5 phosphatase activity, but also reduced the interaction of PGAM5 with NRF2, which facilitated nuclear translocation of NRF2 to prevent BBB disruption from ischemia. Furthermore, LFHP-1c administration by targeting PGAM5 shows a trend toward reduced infarct volume, brain edema and neurological deficits in nonhuman primate
ABSTRACT
BACKGROUND: Current research on Eucommia ulmoides Oliv. mainly focuses on its use in the treatment of osteoarthritis that Eucommia ulmoides Oliv. can enhance the healing ability of bone tissue. However, research on its bone repair ability in periapical periodontitis has not been reported. OBJECTIVE: To study the effect of alcohol extract of Eucommia ulmoides Oliv. on cathepsin K expression in periapical periodontitis rats. METHODS: Twenty-four Sprague-Dawley rats were divided into normal control group (n=4) and apical periodontitis group (n=20). In the periapical periodontitis group, a periapical periodontitis model was established after exposure of the dental pulp in the first molar of the right mandible. The normal control group did not deal with any treatment. After 4 weeks of feeding, four rats from each group were taken for micro-CT detection. Bone destruction was quantified to confirm whether the rat model of periapical periodontitis was successfully constructed. After 5 weeks of feeding, the remaining 16 rats with periapical periodontitis were equally randomized into alcohol extract group (given alcohol extract of Eucommia ulmoides Oliv. via intragastric administration, 5 mL/kg per day) and normal saline group (given the same dose of normal saline via intragastric administration every day). After 4 weeks of gavage, four mice from each group were selected to perform micro-CT examination. The ability of alcohol extract of Eucommia ulmoides Oliv. to repair periapical bone tissue was analyzed. First molars of the right mandible from the other four rats in each group were extracted to detect the expression of cathepsin K in the alveolar bone using immunohistochemical staining. RESULTS AND CONCLUSION: Micro-CT results showed that the rat model of periapical periodontitis was successfully constructed as there was a significant difference in the bone resorption volume between the normal control and apical periodontitis groups [(0.223±0.009) mm3 vs. (0.945±0.037) mm3, P=0.00]. After 4 weeks of gavage, the micro-CT results showed that the alcohol extract of Eucommia ulmoides Oliv. significantly reduced the bone resorption volume in the rat model of periapical periodontitis (P < 0.05). Immunohistochemistry results showed that the alcohol extract of Eucommia ulmoides Oliv. significantly inhibited the expression of cathepsin K, a marker of bone destruction, in the rat model of periapical periodontitis. Therefore, these findings indicate that the alcohol extract of Eucommia ulmoides Oliv. can inhibit the expression of cathepsin K and promote the healing of bone tissue in the rats with periapical periodontitis.