Flavonoid constituents and protective efficacy of Citrus reticulate (Blanco) leaves ethanolic extract on thioacetamide-induced liver injury rats.

Context: Oxidative stress leads to deleterious processes in the liver that resulted in liver diseases.Objective: To evaluate antioxidant activity and hepatoprotective potential of ethanolic leaves extract of Citrus reticulate against hepatic dysfunction induced by thioacetamide (TAA).Materials and Methods: Flavonoid constituents were isolated from the ethanol extract by chromatographic techniques and identified by the spectroscopic analyses. Antioxidant activity was determined using DPPH assay. Hepatotoxicity was induced in rats via intraperitoneal injection of TAA and the ethanol extract was orally administrated at a dose of 100 mg/kg/day for four weeks. Serum biomarkers, hepatic antioxidant enzymes, tumour necrosis factor-alpha (TNF-α), hepatic hydroxyproline levels, and histopathology were examined.Results: Ten known flavonoids were identified, among of them, 6,3`-dimethoxyluteolin and 8,3`-dimethoxyluteolin possessed the highest antioxidant activity. The substantially elevated serum enzymatic levels of ALT, ALP, and bilirubin were found to be restored towards normalisation significantly by the plant extract. Furthermore, the markers including MDA, GSH, SOD, NO, and protein carbonyl which were close to oxidative damage, were restored. Meanwhile, the extract treatment decreased TNF-α level and also was able to reverse the induced fibrosis by significantly reducing the hydroxyproline content. Moreover, histopathological studies further substantiate the protective effect of the extract.Conclusion: C. reticulate leaves extract is a rich source of phytochemicals with in vitro and in vivo protective effects.

A new acylated flavone glycoside, in vitro antioxidant and antimicrobial activities from Saudi Diospyros mespiliformis Hochst. ex A. DC (Ebenaceae) leaves.

Phytochemical investigation of Diospyros mespiliformis leaves resulted in the isolation of new acylated flavone isoscutellarein 7-O-(4'''-O-acetyl)-ß-allopyranosyl(1''' â†’ 2'')-ß-glucopyranoside (1), along with eight known flavonoid metabolites, luteolin 3',4',6,8-tetramethyl ether (2), luteolin 4'-O-ß-neohesperidoside (3), luteolin 7-O-ß-glucoside (4), luteolin (5), quercetin (6), quercetin 3-O-ß-glucoside (7), quercetin 3-O-α-rhamnoside (8), and rutin (9). Their structures were identified by analysis of spectroscopic (UV, NMR, and MS) data, as well as by acid hydrolysis for the isolated glycosides. The antioxidant activity of D. mespiliformis metabolites was determined by the DPPH radical-scavenging assay. The new acylated flavone (1) and flavonol O-rhamnoside (8) displayed the highest antioxidant activities with IC50 values 15.46 and 12.32 µg/mL, respectively, with respect to the antioxidant ascorbic acid (IC50 value 10.62 µg/mL). In addition, the isolated flavonoids were evaluated against four human pathogenic bacteria where the methylated flavone (2) exhibited potent activity against Escherichia coli with inhibition zone 34 mm, and mild activity of flavonol O-rhamnoside (8) against Staphylococcus aureus with MIC value 9.77 µg/mL. According to the MBC/MIC ratio, the antibacterial activity of the isolated flavonoids was considered flavonoid 2 is bactericidal nature against S. aureus, and flavonoids 3 and 4 are bactericidal against E. coli.

Pentagalloyl Glucose, a Major Compound in Mango Seed Kernel, Exhibits Distinct Gastroprotective Effects in Indomethacin-Induced Gastropathy in Rats via Modulating the NO/eNOS/iNOS Signaling Pathway.

Gastric ulcers are a common health disorder that affect up to 10% of the world's population. The gastroprotective potential of pentagalloyl glucose (PGG) against indomethacin-induced ulcer in rats and the possible underlying mechanisms were investigated. Gastric ulceration was induced by indomethacin (single dose, 60 mg/kg). Pretreatment with PGG (100 or 200 mg/kg, orally) for 8 days prior to the administration of indomethacin furnished significant reductions in gastric mucosal lesions as well as a significant increase in mucus concentration. Also, PGG significantly declined the elevations in gastric mucosal MDA, TNF-α, IL-6, PECAM-1, VEGF, and iNOS expression. It also mitigated the decrease in GSH and GPx and eNOS expression observed with indomethacin. The protective effects furnished by PGG were comparable to that of famotidine. The obtained results suggested that the anti-ulcer effects of PGG are mediated by increasing mucus production, scavenging free radicals, decreasing inflammation, and attenuating the NO/NOS signaling in favor of eNOS. To sum up, PGG could provide a potential therapy for gastric ulcer after evaluating its efficacy and effectiveness.

A New Polyoxygenated Flavonol Gossypetin-3-O-ß-d-Robinobioside from Caesalpinia gilliesii (Hook.) D. Dietr. and In Vivo Hepatoprotective, Anti-Inflammatory, and Anti-Ulcer Activities of the Leaf Methanol Extract.

A hitherto unknown polyoxygenated flavonol robinobioside (gossypetin-3-O-ß-d-robinobioside) was isolated from the leaves of Caesalpinia gilliesii along with thirteen known phenolic secondary metabolites. The isolated compounds were characterized using spectroscopic analysis, including 1D and 2D NMR and mass spectrometry (MS) analyses. The extract reduced the level of liver damage in CCl4-induced liver injury in rats. A decrease of the liver biomarkers-aspartate aminotransferase (AST) and alanine aminotransferase (ALT) and an increase of total antioxidant capacity (TAC) levels-were observed similar to the liver protecting drug silymarin. In addition, the extract showed promising activity against carrageenan-induced paw edema in rats and protected their stomachs against ethanol-induced gastric ulcers in a concentration dependent fashion. The observed activities could be attributed to the high content of antioxidant polyphenols. Our results suggest that the C. gilliesii has the capacity to scavenge free radicals and can protect against oxidative stress, and liver and stomach injury.

Flavonoid constituents of Dobera glabra leaves: amelioration impact against CCl4-induced changes in the genetic materials in male rats.

CONTEXT: Dobera glabra (Forssk.) Poir (Salvadoraceae) is a highly valued tree with diverse importance as special mineral sourced feed and a folkloric tool for forecasting droughts. However, there are no reports on its phytochemical and biological investigations. OBJECTIVE: Phytochemical investigation of D. glabra leaves and its protective potential against CCl4 inducing changes in the genetic materials. MATERIALS AND METHODS: D. glabra extract, DGE (70% MeOH/H2O), was applied to polyamide column chromatography, eluting with MeOH/H2O of decreasing polarities, followed by preparative chromatographic tools, yielded seven compounds. Three DGE doses (50, 100 and 200 mg/kg bw/d) were administrated for 8 weeks intragastrically to male albino rats prior treated with CCl4 (0.5 mL/kg/bw). The reactive oxygen species (ROS) levels, expression changes of glutamate transporters (GLAST, GLT-1 and SNAT3) mRNA, DNA fragmentation and glutathione peroxidase (GPx) activity were investigated in the liver tissues of these rats. RESULTS: Isorhamnetin-3-O-ß-glucopyranoside-7-O-α-rhamnopyranoside, isorhamnetin-3-O-α-rhamnopyranoside-7-O-ß-glucopyranoside, kaempferol-3,7-di-O-α-rhamnopyranoside, isorhamnetin-3-O-ß-glucopyranoside, kaempferol-3-O-ß-glucopyranoside, isorhamnetin and kaempferol were identified. DGE (200 mg/kg bw) + CCl4 exhibited the most significant reduction in ROS levels and DNA fragmentation with 251.3% and141% compared to 523.1% and 273.2% for CCl4, respectively. Additionally, it increased significantly the mRNA expression of GLAST, GLT-1 and SNAT3 to 2.16-, 1.72- and 2.09-fold, respectively. Also, GPx activity was increased to 4.8 U/mg protein/min compared to CCl4 (1.8 U/mg protein/min). DISCUSSION AND CONCLUSION: Flavonoid constituents, antioxidant effect and genotoxic protection activity of D. glabra were first reported. DGE may be valuable in the treatment and hindrance of hepatic oxidative stress and genotoxicity.

A new alpha-methylanthraquinone glucoside from Emex spinosus.

A new alpha-methylanthraquinone glucoside, laccaic acid D 8-o-beta-D-glucoside, and six known anthraquinones have been isolated from the aqueous alcoholic extract of Emex spinosus (L.) Campd. (Polygonaceae), together with two known flavonol glycosides. The structures were determined by conventional analytical methods and confirmed by MS and NMR spectral analysis, including 2D experiments for the new compound.