Effects of gastrodin against carbon tetrachloride induced kidney inflammation and fibrosis in mice associated with the AMPK/Nrf2/HMGB1 pathway.

Gastrodin (GAS), the main phenolic glycoside extracted from Gastrodia elata Blume, exhibits potential renoprotective properties. Here, we examined the protective effects of GAS on carbon tetrachloride (CCl4)-induced kidney inflammation and fibrosis in mice, and explored its underlying mechanisms. Our research findings revealed that GAS improved CCl4-induced renal damage in mice. GAS inhibited kidney fibrosis and the deposition of collagen and α-smooth muscle actin (α-SMA). GAS suppressed CCl4-induced inflammation in kidney tissue, as indicated by the decreased levels of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). The renoprotective effects of GAS were associated with inhibiting oxidative stress by regulating nuclear factor-erythroid 2-related factor 2 (Nrf2)-mediated antioxidant signaling and increasing adenosine 5'-monophosphate activated protein kinase (AMPK) activation. Furthermore, GAS supplementation inactivated the receptor for advanced glycation end products (RAGE) and the high-mobility group box-1 (HMGB1) pathway. GAS inhibited the activation of Toll-like receptors (TLRs), nuclear factor-kappa B (NF-κB) and transforming growth factor (TGF)-ß. Collectively, this study clarified that GAS attenuates CCl4-induced kidney inflammation and fibrosis via the AMPK/Nrf2/HMGB1 pathway.

Ampelopsin attenuates carbon tetrachloride-induced mouse liver fibrosis and hepatic stellate cell activation associated with the SIRT1/TGF-ß1/Smad3 and autophagy pathway.

Ampelopsin (Amp), a natural flavonoid found in the vine tea of Ampelopsis grossedentata, exhibited anti-cancer, anti-oxidant, anti-inflammatory, anti-apoptosis and hepatoprotective properties. The current study instigates the protective effect of Amp on carbon tetrachloride (CCl4)-induced hepatic fibrosis and explores its underlying mechanisms. The results indicated Amp decreased the levels of liver injury markers. Amp inhibited liver fibrosis, as indicated by decreases in hepatic collagen deposition, extracellular matrix (ECM) deposition and α-smooth muscle actin (α-SMA). Amp blocked the activation of hepaticstellate cells (HSCs) by decreasing the expression of collage I, α-SMA, tissue inhibitor of matrix metalloproteinases (TIMPs) 1, transforming growth factor (TGF)-ß1, phosphorylated Smad3 (p-Smad3) and increasing the expression of matrix metalloproteinases (MMPs) 9 and SIRT1 in the model of liver fibrosis and cultured HSCs. The sirtuin 1 (SIRT1) specific inhibitor Sirtinol activated the TGF-ß1/Smad3 pathway and enhanced ECM accumulation. Attractively, Amp up-regulates the expression of autophagy-related proteins microtubule-associated protein light chain three II (LC3-II) and Beclin-1 in vivo and in vitro. However, depletion of autophagy by specific inhibitor 3-MA obviously abolished the inhibiting effect of Amp on HSC activation and hepatic fibrosis. Conclusively, these results suggest that Amp could decrease CCl4-induced hepatic fibrosis through regulating the SIRT1/TGF-ß1/Smad3 and autophagy pathway.

Protective role of quercetin against lead-induced inflammatory response in rat kidney through the ROS-mediated MAPKs and NF-κB pathway.

BACKGROUND: Lead (Pb) exposure is considered as a risk factor for the development of renal dysfunction. The flavonoid quercetin (QE) in diets exerts the nephroprotective effects. This study investigated the effects of quercetin on renal oxidative stress and inflammation in rats exposed to Pb. METHODS: Wistar rats were divided into normal, lead exposure groups, lead plus quercetin groups and quercetin groups. Rats were exposed to lead acetate in the drinking water (500mgPb/L) with or without quercetin co-administration (25 and 50mgQU/kg intragastrically once daily). After 75days, serum uric acid, urea, creatinine, renal reactive oxygen species (ROS) production, thiobarbituric acid reactive substances (TBARS) and histopathological analysis were performed. Pb content in kidney was also assayed. The levels of tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1ß), interleukin-6 (IL-6), cyclooxygenase-2 (COX-2), the extracellular-receptor kinases (ERK1/2), the c-Jun N-terminal kinases (JNK1/2), p38 MAPK and nuclear factor-κB (NF-κB) were measured. RESULTS: Quercetin significantly prevented Pb-induced nephrotoxicity in a dose-dependent manner, indicated by both diagnostic indicators and histopathological analysis. Quercetin significantly decreased Pb content in kidney. Pb-induced profound elevations of oxidative stress in kidney were suppressed by quercetin. Furthermore, quercetin significantly inhibited Pb-induced inflammation in rat kidney. CONCLUSIONS: These results suggest that quercetin has the nephroprotective actions. The inhibition of Pb-induced kidney inflammation by quercetin is due at least in part to its anti-oxidant activity and its ability to modulate the MAPK and NF-κB signaling pathway. GENERAL SIGNIFICANCE: Quercetin might be a potent nephroprotective drug to protect Pb-induced kidney injury.

Puerarin protects rat kidney from lead-induced apoptosis by modulating the PI3K/Akt/eNOS pathway.

Puerarin (PU), a natural flavonoid, has been reported to have many benefits and medicinal properties. However, its protective effects against lead (Pb) induced injury in kidney have not been clarified. The aim of the present study was to investigate the effects of puerarin on renal oxidative stress and apoptosis in rats exposed to Pb. Wistar rats were exposed to lead acetate in the drinking water (500mg Pb/l) with or without puerarin co-administration (100, 200, 300 and 400mg PU/kg intragastrically once daily) for 75days. Our data showed that puerarin significantly prevented Pb-induced nephrotoxicity in a dose-dependent manner, indicated by both diagnostic indicators of kidney damage (serum urea, uric acid and creatinine) and histopathological analysis. Moreover, Pb-induced profound elevation of reactive oxygen species (ROS) production and oxidative stress, as evidenced by increasing of lipid peroxidation level and depleting of intracellular reduced glutathione (GSH) level in kidney, were suppressed by treatment with puerarin. Furthermore, TUNEL assay showed that Pb-induced apoptosis in rat kidney was significantly inhibited by puerarin. In exploring the underlying mechanisms of puerarin action, we found that activities of caspase-3 were markedly inhibited by the treatment of puerarin in the kidney of Pb-treated rats. Puerarin increased phosphorylated Akt, phosphorylated eNOS and NO levels in kidney, which in turn inactivated pro-apoptotic signaling events including inhibition of mitochondria cytochrome c release and restoration of the balance between pro- and anti-apoptotic Bcl-2 proteins in kidney of Pb-treated rats. In conclusion, these results suggested that the inhibition of Pb-induced apoptosis by puerarin is due at least in part to its antioxidant activity and its ability to modulate the PI3K/Akt/eNOS signaling pathway.

Puerarin protects the rat liver against oxidative stress-mediated DNA damage and apoptosis induced by lead.

Puerarin (PU), a natural flavonoid, has been reported to have many benefits and medicinal properties. In this study, we valuated the protective effect of puerarin against lead-induced oxidative DNA damage and apoptosis in rat liver. A total of forty male Wistar rats (8-week-old) was divided into 4 groups: control group; lead-treated group (500 mg Pb/l as the only drinking fluid); lead+puerarin treated group (500 mg Pb/l as the only drinking fluid plus 400 mg PU/kg bwt intra-gastrically once daily); and puerarin-treated group (400 mg PU/kg bwt intra-gastrically once daily). The experimental period was lasted for 75 successive days. Our data showed that puerarin significantly effectively improved the lead-induced histology changes in rat liver and decreased the serum ALT and AST activities in lead-treated rats. Puerarin markedly restored Cu/Zn-SOD, CAT and GPx activities and the GSH/GSSG ratio in the liver of lead-treated rat. Furthermore, the increase of 8-hydroxydeoxyguanosine induced by lead was effectively suppressed by puerarin. The enhanced caspase-3 activity in the rat liver induced by lead was also inhibited by puerarin. TUNEL assay showed that lead-induced apoptosis in rat liver was significantly inhibited by puerarin, which might be attributed to its antioxidant property. In conclusion, these results suggested that puerarin could protect the rat liver against lead-induced injury by reducing ROS production, renewing the activities of antioxidant enzymes and decreasing DNA oxidative damage.

Protective role of puerarin on lead-induced alterations of the hepatic glutathione antioxidant system and hyperlipidemia in rats.

Puerarin (PU), a natural flavonoid, has been reported to have many benefits and medicinal properties. The aim of the present study was to investigate the effects of puerarin on hepatic oxidative stress and hyperlipidemia in rats exposed to lead. Our data showed that puerarin significantly prevented lead-induced hepatotoxicity, indicated by both diagnostic indicators of liver damage (serum aminotransferase levels) and histopathological analysis. Moreover, lead-induced profound elevation of ROS production and oxidative stress, as evidenced by increasing of lipid peroxidation level, reducing of GPx, GST, GR and GCL activities and depleting of intracellular reduced GSH level in liver, were suppressed by treatment with puerarin. Furthermore, the increase of serum cholesterol, triglycerides and LDL induced by lead was effectively suppressed by puerarin. The HDL level in the lead treatment rats was also increased by puerarin. Western blot analysis showed that puerarin remarkably inhibited hyperlipidemia by regulating the expression of cholesterol 7a-hydroxylase (CYP7A1), 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) and low-density lipoprotein receptor (LDL-R) in liver of lead treated rats. Altogether, these results suggest that puerarin could protect the lead-induced liver injury and hyperlipidemia by reducing ROS production, renewing the activities of antioxidant enzymes and influencing expression of hepatic lipid biosynthesis and metabolism genes.

Ganoderma applanatum terpenes protect mouse liver against benzo(α)pyren-induced oxidative stress and inflammation.

Ganoderma applanatum terpenes (GAT) have been reported to have many benefits and medicinal properties. In this study, we evaluated the protective effect of GAT against benzo(a)pyrene (BaP) induced oxidative stress and inflammation in mouse liver, and explored the potential mechanism of its action. Our data showed that GAT significantly decreased levels of ALT and AST in serum and the liver histological injury in BaP-treated mice. GAT markedly decreased the levels of ROS, MDA and lowered the GSH/GSSG ratio in the liver of BaP-treated mice. Furthermore, GAT markedly inhibited the BaP-induced increase of Cu/Zn-SOD, CAT, GPx and GST activities in the mouse liver. Western blot analysis showed that GAT significantly inhibited inflammation by pressing the expression of IL-1ß and COX-2 and inhibiting NF-κB translocation in the liver of BaP-treated mice. In conclusion, these results suggested that GAT could protect the mouse liver against BaP-induced injury by improving hepatic function, attenuating histopathologic changes, decreasing levels of ROS and MDA, renewing the activities of antioxidant enzymes and suppressing inflammatory response.

Quercetin protects the rat kidney against oxidative stress-mediated DNA damage and apoptosis induced by lead.

Quercetin, a flavonoid, effectively improved the lead-induced histology changes including structure damage and leukocyte infiltration in rat kidney. The present study was designed to explore the protective mechanism of quercetin against lead-induced oxidative DNA damage and apoptosis in rat kidney. We found that quercetin markedly decreased the ROS level and lowered the GSH/GSSG ratio in the kidney of lead-treated rat. The increase of 8-hydroxydeoxyguanosine level in the kidney of lead-treated rat was effectively suppressed by quercetin. Furthermore, quercetin markedly restored Cu/Zn-SOD, CAT and GPx activities in the kidney of lead-treated rat. TUNEL assay showed that lead-induced apoptosis in rat kidney was significantly inhibited by quercetin, which might be attributed to its antioxidant property. In conclusion, these results suggested that quercetin could protect the rat kidney against lead-induced injury by improving renal function, attenuating histopathologic changes, reducing ROS production, renewing the activities of antioxidant enzymes, decreasing DNA oxidative damage and apoptosis.