IDH2 deficiency increases the liver susceptibility to ischemia-reperfusion injury via increased mitochondrial oxidative injury.

Mitochondrial NADP+-dependent isocitrate dehydrogenase 2 (IDH2) is a major producer of mitochondrial NADPH, required for glutathione (GSH)-associated mitochondrial antioxidant systems including glutathione peroxidase (GPx) and glutathione reductase (GR). Here, we investigated the role of IDH2 in hepatic ischemia-reperfusion (HIR)-associated mitochondrial injury using Idh2-knockout (Idh2-/-) mice and wild-type (Idh2+/+) littermates. Mice were subjected to either 60min of partial liver ischemia or sham-operation. Some mice were administered with 2-(2,2,6,6-tetramethylpiperidin-1-oxyl-4-ylamino)-2-oxoethyl) triphenylphosphonium chloride (mito-TEMPO, a mitochondria-targeting antioxidant). HIR induced severe histological and functional damages of liver in both Idh2+/+ mice and Idh2-/- mice and those damages were more severe in Idh2-/- mice than in wild-type littermates. HIR induces dysfunction of IDH2, leading to the decreases of NADPH level and mitochondrial GR and GPx functions, consequently resulting in mitochondrial and cellular oxidative injury as reflected by mitochondrial cristae loss, mitochondrial fragmentation, shift in mitochondrial fission, cytochrome c release, and cell death. These HIR-induced changes were greater in Idh2-/- mice than wild-type mice. The mito-TEMPO supplement significantly attenuated the aforementioned changes, and these attenuations were much greater in Idh2-/- mice when compared with wild-type littermates. Taken together, results have demonstrated that HIR impairs in the IDH2-NADPH-GSH mitochondrial antioxidant system, resulting in increased mitochondrial oxidative damage and dysfunction, suggesting that IDH2 plays a critical role in mitochondrial redox balance and HIR-induced impairment of IDH2 function is associated with the pathogenesis of ischemia-reperfusion-induced liver failure.

Bisabolangelone isolated from Ostericum koreanum inhibits the production of inflammatory mediators by down-regulation of NF-kappaB and ERK MAP kinase activity in LPS-stimulated RAW264.7 cells.

Bisabolangelone, a sesquiterpene derivative, was isolated from the roots of Osterici Radix (Ostericum koreanum Maximowicz). In this study, the anti-inflammatory effect of bisabolangelone was investigated to address potential therapeutic effects in lipopolysaccharide (LPS)-stimulated mouse macrophage RAW 264.7 cells. Bisabolangelone significantly inhibited NO, PGE(2), and pro-inflammatory cytokines by suppressing the mRNA and protein expressions of iNOS and COX-2. Bisabolangelone also inhibited the productions of pro-inflammatory cytokines (TNF-alpha, IL-1beta and IL-6) by suppressing the cytokine mRNA and protein expressions. The molecular mechanism of bisabolangelone-mediated attenuation in RAW 264.7 cells has a close relationship to suppressing the translocation of nuclear factor-kappaB (NF-kappaB) p65 subunit into the nucleus and the phosphorylation of mitogen-activated protein kinases (MAPKs). These results indicate that bisabolangelone inhibits LPS-stimulated inflammation through the blocking of NF-kappaB and MAPK pathways in macrophages, and demonstrated that bisabolangelone possesses anti-inflammatory properties.

Wen-pi-tang-Hab-Wu-ling-san reduces ureteral obstructive renal fibrosis by the reduction of oxidative stress, inflammation, and TGF-beta/Smad2/3 signaling.

Kidney fibrosis results in chronic renal disease. The current treatment of chronic renal diseases is limited to angiotensin converting enzyme inhibitors and angiotensin receptor blockers. Recently, we found that Wen-pi-tang-Hab-Wu-ling-san (WHW) extract, which has been used to treat renal diseases in herbal medicine for a long time, plays anti-fibrogenic. Here, we investigated the role of WHW in the kidney fibrosis induced by unilateral ureteral obstruction (UUO) in mice. C57BL/6 male mice were subjected to UUO on day 0 and then administered with either WHW (2, 10, or 50 mg/kg of body weight) or vehicle orally from 1 day after UUO to finish the experiment. WHW-administration significantly mitigated the UUO-induced kidney fibrotic changes including tubular atrophy and dilatation, collagen accumulation, expansion of interstitial space and leukocyte infiltration. WHW prevented the increases of oxidative stress by the prevention of UUO-induced decreases of catalase, copper-zinc superoxide dismutase (CuZnSOD) and manganese superoxide dismutase (MnSOD), resulting in reduced production of oxidative stress. Furthermore, WHW reduced transforming growth factor-beta (TGF-beta) expression and phosphorylation of Smad2/3 stimulated by UUO. In conclusion, WHW prevented kidney fibrosis following UUO by the inhibition of inflammation, oxidative stress and TGF-beta/Smad2/3 signaling pathway.

Wen-pi-tang-Hab-Wu-ling-san attenuates kidney fibrosis induced by ischemia/reperfusion in mice.

Renal fibrosis is highly implicated as a cause of chronic renal failure, for which suitable therapeutics have not yet been developed. Recently, it was reported that Wen-pi-tang-Hab-Wu-ling-san (WHW) extract attenuates epithelial cells undergoing mesenchymal transition in cultured Madin-Darby canine kidney cells. This study investigated whether WHW extract prevents renal fibrosis induced by ischemia/reperfusion (I/R) in mice. Ischemia/reperfusion resulted in kidney fibrosis at 14 days after the procedure. When WHW was administered orally to mice beginning from 2 days after the onset of ischemia until killing, the fibrosis was significantly reduced. WHW administration significantly prevented a post-ischemic decrease of copper-zinc superoxide dismutase (CuZnSOD) and manganese superoxide dismutase (MnSOD) activities, leading to decreased lipid peroxidation and hydrogen peroxide production. In addition, WHW administration attenuated the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and c-Jun N-terminal kinase 1/2 (JNK1/2) and attenuated the activation of nuclear factor-kappa B (NF-kappaB) in the kidneys subjected to ischemia. In conclusion, WHW extract attenuated the renal fibrosis and the attenuation was associated with a reduction of oxidative stress and an inhibition of ERK1/2, JNK1/2, p38 and NF-kappaB activation. WHW extract may be an attractive agent to attenuate the progression of fibrosis.

Wen-Pi-Tang-Hab-Wu-Ling-San extract inhibits the release of inflammatory mediators from LPS-stimulated mouse macrophages.

AIM OF THE STUDY: Wen-Pi-Tang is a traditional herbal prescription that has been used traditionally for the treatment of various inflammatory diseases, including chronic renal failure, renal injury, renal tubular cell damage and diabetic nephropathy. In this study, we investigated the pharmacological activity of modified Wen-Pi-Tang, Wen-Pi-Tang-Hab-Wu-Ling-San (WHW) extract. MATERIALS AND METHODS: Production of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-6 and NO in supernatant, mRNA expression of TNF-alpha, IL-1beta, IL-6 and iNOS, protein expression of iNOS, phosphorylation of mitogen-activated protein kinases (MAPKs) and activation of nuclear factor-kappa B in the extract were assayed. RESULTS: We found that WHW extract had potent anti-inflammatory effects in LPS-stimulated RAW264.7 cells and primary peritoneal macrophages. WHW extract strongly inhibited the excessive production of inflammatory mediators, nitric oxide (NO), TNF-alpha (TNF-alpha), interleukin 1-beta (IL-1beta) and IL-6 in LPS-stimulated macrophages. The inhibition of inducible nitric oxide synthase (iNOS) and these cytokines resulted from the reduced expressions of mRNAs of iNOS and these cytokines, respectively. WHW extract attenuated the phosphorylation of mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinases 1 and 2 (ERK1/2) and c-Jun N-terminal kinase (JNK), as well as the activation of nuclear factor-kappa B (NF-kappaB) in LPS-stimulated RAW264.7 cells. CONCLUSIONS: These data suggest that WHW extract may exhibit anti-inflammatory effects through the modulation of MAPK and the NF-kappaB-dependent pathway involved in inflammation.

Wen-pi-tang-Hab-Wu-ling-san attenuates kidney ischemia/reperfusion injury in mice. A role for antioxidant enzymes and heat-shock proteins.

The purpose of this study was to investigate the effects of Wen-pi-tang-Hab-Wu-ling-san (WHW) extract, which has been used for treatment of renal diseases, on kidney ischemia/reperfusion (I/R) injury. Thirty minutes of bilateral renal ischemia resulted in disruption of kidney tubular epithelial cells and increased plasma creatinine levels in mice, however these effects were significantly attenuated when WHW was administered prior to I/R. WHW-administration also inhibited post-ischemic decreases of catalase, copper-zinc superoxide dismutase (CuZnSOD), and manganese superoxide dismutase (MnSOD) activity in kidney tissue, leading to decreased tissue hydrogen peroxide levels and lipid peroxidation. Post-ischemic increases of heat-shock protein (HSP)-27 and -72 expressions were greater in mouse kidneys that received WHW. In conclusion, WHW-administration reduced kidney susceptibility to I/R injury, and this reduced susceptibility was associated with greater post-ischemic activation of catalase, CuZnSOD and MnSOD, resulting in reduced hydrogen peroxide levels and lipid peroxidation, as well as higher post-ischemic expression of HSP-27 and -72.

Wen-pi-tang-Hab-Wu-ling-san, an oriental herbal prescription, attenuates epithelial-mesenchymal transdifferentiation stimulated by TGF-beta1 in kidney cells.

Wen-pi-tang-Hab-Wu-ling-san (WHW), an oriental herbal prescription, is currently used in oriental clinics for the treatment of chronic renal failure (CRF). While its effectiveness has been supported by a series of modern studies, the underlying mechanism remains poorly understood. CRF progression involves tubulointerstitial fibrosis where transforming growth factor-beta1 (TGF-beta1) plays a critical role by inducing epithelial-mesenchymal transdifferentiation (EMT). This study examined whether WHW extract attenuated the TGF-beta1-induced EMT in Madin-Darby canine kidney cells. When the cells were stimulated by TGF-beta1 (2.5 ng/mL), they exhibited an elongated, spindle-shaped appearance but this morphological change was significantly suppressed by WHW extract (1 mg/mL). The WHW extract did not show notable cytotoxicity and even mitigated the cytotoxic effects of TGF-beta1. It inhibited the expression of alpha-smooth muscle actin (alpha-SMA), a marker of EMT, but not the secretion of matrix metalloproteinases stimulated by TGF-beta1. The WHW extract also inhibited the phosphorylation of Smad2 that mediates TGF-beta1 signaling leading to alpha-SMA expression. The present study suggests that WHW extract may provide renal protective effects through modulation of the TGF-beta1/Smad2/alpha-SMA pathway involved in fibrosis.

Ginsenosides protect apical transporters of cultured proximal tubule cells from dysfunctions induced by h(2)o(2).

Oxidative stress has been implicated as a primary cause of renal failure in certain renal diseases. Indeed, renal proximal tubule is a very sensitive site to oxidative stress and retains functionally fully characterized transporters. It has been reported that ginsenosides have a beneficial effect on diverse diseases including oxidative stress. However, the protective effect of ginsenosides on oxidative stress has not been elucidated in renal proximal tubule cells. Thus, we examined the effect of ginsenosides on oxidative stress-induced alteration of apical transporters and its related mechanism in renal proximal tubule cells. In the present study, hydrogen peroxide (H(2)O(2)) (>10(-5) M) inhibited alpha-methyl-D-glucopyranoside uptake in a dose-dependent manner (p < 0.05). It also inhibited Pi and Na(+) uptake. At a concentration of 20 microg/ml, total ginsenosides significantly reduced H(2)O(2)-induced inhibition of apical transporters. In contrast, protopanaxadiol (PD) and protopanaxatriol (PT) saponins exhibited a less preventive effect than total ginsenosides (p < 0.05). Furthermore, we examined its action mechanism. H(2)O(2) increased lipid peroxide formation, arachidonic acid (AA) release, and Ca(2+) uptake. These effects on H(2)O(2) were significantly prevented by total ginsenosides and PD or PT sanponins. However, total ginsenosides appear to be more protective than PD and PT saponins (p < 0.05). In conclusion, ginsenosides prevented H(2)O(2)-induced inhibition of apical transporters via a decrease in oxidative stress, AA release, and Ca(2+) uptake in primary cultured renal proximal tubule cells.

Effect of caffeic acid on apical transporters' dysfunction of renal proximal tubule cells under oxidative stress in vitro.

The protective effect of caffeic acid (CA) against oxidative stress-induced inhibition of proximal tubule apical transporter was investigated. In the present study, 10 (-4) M H2O2 did not affect cell viability regardless of incubation time. However, it decreased apical transporters' activity such as Na (+)/glucose cotransporter, Na (+)/Pi cotransporter, and Na (+)/H(+) antiporter in the proximal tubule cells. CA (>10(-6) M) prevented H2O2-induced inhibition of apical transporters. Thus, we investigated its action mechanism. CA also prevented H2O2-induced lipid peroxides formation, arachidonic acid (AA) release, and Ca(2+) uptake. In conclusion, CA, in part, prevented H2O2-induced inhibition of apical transporter activity via decrease of AA release and Ca(2+) uptake in primary cultured renal proximal tubule cells.