Melatonin Attenuates Mitochondrial Damage in Aristolochic AcidInduced Acute Kidney Injury

Aristolochic acid (AA), extracted from Aristolochiaceae plants, plays an essential role in traditional herbal medicines and is used for different diseases. However, AA has been found to be nephrotoxic and is known to cause aristolochic acid nephropathy (AAN).AA-induced acute kidney injury (AKI) is a syndrome in AAN with a high morbidity that manifests mitochondrial damage as a key part of its pathological progression. Melatonin primarily serves as a mitochondria-targeted antioxidant. However, its mitochondrial protective role in AA-induced AKI is barely reported. In this study, mice were administrated 2.5 mg/kg AA to induce AKI. Melatonin reduced the increase in Upro and Scr and attenuated the necrosis and atrophy of renal proximal tubules in mice exposed to AA. Melatonin suppressed ROS generation, MDA levels and iNOS expression and increased SOD activities in vivo and in vitro. Intriguingly, the in vivo study revealed that melatonin decreased mitochondrial fragmentation in renal proximal tubular cells and increased ATP levels in kidney tissues in response to AA. In vitro, melatonin restored the mitochondrial membrane potential (MMP) in NRK-52E and HK-2 cells and led to an elevation in ATP levels. Confocal immunofluorescence data showed that puncta containing Mito-tracker and GFP-LC3A/B were reduced, thereby impeding the mitophagy of tubular epithelial cells. Furthermore, melatonin decreased LC3A/B-II expression and increased p62 expression. The apoptosis of tubular epithelial cells induced by AA was decreased. Therefore, our findings revealed that melatonin could prevent AA-induced AKI by attenuating mitochondrial damage, which may provide a potential therapeutic method for renal AA toxicity.

The risk factors of electrocardiographic abnormality in patients with acute cerebral infarction / 中国医师杂志

Objective To evaluate the risk factors of electrocardiographic abnormality in patients with acute cerebral infarction.Methods The clinical data of patients with acute cerebral infarction were collected,including the National Institutes of Health Stroke Scale (NIHSS),electrocardiogram (ECG),lipid,glucose,glycosylated hemoglobin,body mass index,homocysteine,high-sensitivity C-reactive protein,white blood cells,and medical history.Logistics regression was used to search the risk factors of ECG abnormality in patient with acute cerebral infarction.Results ECGs of 189 cases of patients with acute cerebral infarction were divided into normal (n =83) and abnormal (n =106).The rate of abnormal ECG was 56.09％,and abnormal ECG ST-T change was the most common.NIHSS,systolic blood pressure,total cholesterol,and white blood cells were correlated with the ECG abnormality with the one-way Logistic regression analysis.In addition,NIHSS,systolic blood pressure,and white blood cells were correlated with the ECG abnormality with the multiple Logistic regression analysis (r =1.18,P ＜0.01 ; r =1.02,P ＜0.01 ; r =1.19,P ＜ 0.05).Conclusions NIHSS,systolic blood pressure,and white blood cells were independent risk factors in patients with acute cerebral infarction.ECG monitoring should be performed especially in patients with high NIHSS,systolic blood pressure,and white blood cells count.