Effects of imperatorin, the active component from Radix Angelicae (Baizhi), on the blood pressure and oxidative stress in 2K,1C hypertensive rats.

The 2-kidney, 1-clip (2K,1C) model of hypertension was used to investigate the potential antihypertensive and antioxidant effect of imperatorin extracted from the root of radix angelicae. After 10 weeks treatment of imperatorin, mean blood pressure (MBP) of 2K,1C hypertensive rats was obtained, and superoxide dismutase (SOD), nitric oxide (NO) and nitric oxide synthase (NOS) were measured. Malondialdehyde (MDA) and glutathione (GSH) levels, catalase (CATA), xanthine oxidase (XOD), angiotensinII (Ang II) and endothelin (ET) levels of kidney were evaluated with commercial kits. Nicotinamide adenine dinucleotidephosphate (NADPH) oxidase subunits of the renal cortial tissues were determined by RT-PCR and Western blot. 8-Iso-prostaglandin F2α (8-iso-PGF2α) of 24h urinary excretion was also measured by ELISA. MBP was significantly reduced by treatment with IMP (6.25, 12.5 and 25 mg/kg/day, i.g.) in 2K,1C hypertensive rats. Meanwhile, we found that renal CATA and XOD activities, GSH levels, plasma NO and NOS contents were significantly increased in IMP-treated groups. Plasma ET, renal Ang II levels, MDA and the 24h urinary excretion of 8-iso-PGF2α in the IMP treated group were lower than control SD group. After that, we found the mRNA expressions and protein levels of NADPH oxidase subunits in the clipped kidney were markedly reduced after IMP treated in 2K,1C hypertensive rats. IMP showed antihypertensive and antioxidant effects in the renal injury of renovascular hypertensive rats, suggesting that IMP could be of therapeutic use in preventing renal injury related hypertension.

Free radicals, antioxidant defense systems, and schizophrenia.

The etiopathogenic mechanisms of schizophrenia are to date unknown, although several hypotheses have been suggested. Accumulating evidence suggests that excessive free radical production or oxidative stress may be involved in the pathophysiology of schizophrenia as evidenced by increased production of reactive oxygen or decreased antioxidant protection in schizophrenic patients. This review aims to summarize the basic molecular mechanisms of free radical metabolism, the impaired antioxidant defense system and membrane pathology in schizophrenia, their interrelationships with the characteristic clinical symptoms and the implications for antipsychotic treatments. In schizophrenia, there is accumulating evidence of altered antioxidant enzyme activities and increased levels of lipid peroxidation, as well as altered levels of plasma antioxidants. Moreover, free radical-mediated abnormalities may contribute to specific aspects of schizophrenic symptomatology and complications of its treatment with antipsychotic drugs, as well as the development of tardive dyskinesia (TD). Finally, the potential therapeutic strategies implicated by the accumulating data on oxidative stress mechanisms for the treatment of schizophrenia are discussed.

Effect of plumbagin on levels of Nox4/ROS andα-SMA in human hepatic stellate cells / 中国病理生理杂志

AIM:To observe the effect of plumbagin on the mRNA and protein expression of nicotinamide ade -nine dinucleotidephosphate oxidase 4 ( Nox4 ) , reactive oxygen species ( ROS ) level and protein expression of α-smooth muscle actin (α-SMA) in the HSC-LX2 cells stimulated with transforming growth factor β1 (TGF-β1) in vitro.METH-ODS:HSC-LX2 cells were cultured in vitro and divided into blank group, model group, high-, medium-and low-dose (2, 1.5 and 1 μmol/L) plumbagin groups .After incubated with each drug for 72 h, the mRNA expression of Nox4 was detec-ted by RT-PCR.ROS levels were tested by in situ loading probe method.The protein contents of Nox4 and α-SMA were measured by Western blot .RESULTS:Compared with model group , after treated with plumbagin for 72 h, the mRNA ex-pression of Nox4, ROS level and α-SMA protein were significantly decreased in high-and medium-dose plumbagin groups (P<0.01).CONCLUSION:Plumbagin inhibits the activation of HSC-LX2 cells via decreasing the expression of Nox4, thus decreasing ROS levels .

ROS-EGFR-JNK-AP-1 signaling pathway involves in angiotensin Ⅱ-induced human mesangial cells proliferation / 中华肾脏病杂志

Objective To elucidate whether Ang Ⅱ indnces the proliferation of mesangial cells through ROS-EGFR-JNK-AP-1 signaling pathway. Methods The incorporation of 3H-thymidine (3H-TdR) and cell count were used to measure mesangial cell (MC) proliferation. ROS production was determined by DCFDA fluorescence. EGFR and JNK activation was assayed by Western blot. Results Ang Ⅱ significantly enhanced ROS production in mesangial cells, which was up-regulated by 2.26 folds of control group after incubation with Ang Ⅱ for 60 min. Ang Ⅱ induced EGFR phosphorylation in dose- and time-dependent manner, with the peak (3.96 folds increase) at 30 min. EGFR phosphorylation was significantly blocked by AT1R antagonist losartan, antioxidant NAC, and NADPH oxidase inhibitor apocynin and DPI. EGFR antagonist AG1478 significantly inhibited Ang Ⅱ-induced mcsangial cell proliferation. Losartan, NAC, apocynin, DPI, and AG1478 ahnost abolished Ang Ⅱ-induced JNK activation. Conclusions ROS-EGFR-JNK-AP-1 signaling pathway is involved in Ang Ⅱ-induced mesangial cell proliferation. Apocynin and AG 1478 may be used as new therapy.