MiR-195 alleviates oxygen-glucose deprivation/reperfusion-induced cell apoptosis via inhibition of IKKα-mediated NF-κB pathway.

OBJECTIVES: Increasing evidence confirmed that miRNA plays a critical role in the occurrence and development of ischemic stroke. Here, the aim of this study was to examine the function and mechanisms of miR-195 in vascular endothelial cell apoptosis induced by oxygen-glucose deprivation (OGD). METHODS: This study intended to use OGD to simulate ischemia in vitro. The mRNA expression of miR-195, IKKα and NF-κB in human umbilical vein endothelial cells (HUVECs) were detected by RT-qPCR. The proliferation and apoptosis ability of HUVECs were evaluated using MTT assay, colony formation assay and flow cytometry, respectively. Western blot was applied to examine related protein expression. The interaction between miR-195 and IKKα was verified by dual-luciferase reporter gene assay. RESULTS: OGD significantly inhibited cell viability and induced cell apoptosis in HUVECs. Meanwhile, OGD treatment notably decreased the expression of miR-195, as well as enhanced NF-κB expression. Moreover, miR-195 directly interacted with IKKα and suppressed its expression. Mechanically, overexpression of miR-195 exhibited pro-proliferation and anti-apoptotic effect on HUVECs treated with OGD through targeting IKKα-mediated NF-κB pathway. At the molecular level, through suppressing IKKα/NF-κB pathway, miR-195 inhibited the expression of pro-apoptotic protein Bax and active caspase-3, but increased the expression of anti-apoptotic Bcl-2 in HUVECs. CONCLUSIONS: Our finding uncovers the protective effect of miR-195 on the biological behavior of HUVECs via suppression of the NF-κB pathway induced by IKKα, which may provide a new potential strategy for ischemic stroke clinical treatment.

[Protective effects of endogenous carbon monoxide against myocardial ischemia-reperfusion injury in rats].

The present study is aimed to explore the effects of endogenous carbon monoxide on the ischemia-reperfusion in rats. Wistar rats were intraperitoneally injected with protoporphyrin cobalt chloride (CoPP, an endogenous carbon monoxide agonist, 5 mg/kg), zinc protoporphyrin (ZnPP, an endogenous carbon monoxide inhibitor, 5 mg/kg) or saline. Twenty-four hours after injection, the myocardial ischemia-reperfusion model was made by Langendorff isolated cardiac perfusion system, and cardiac function parameters were collected. Myocardial cGMP content was measured by ELISA, and the endogenous carbon monoxide in plasma and myocardial enzymes in perfusate at 10 min after reperfusion were measured by colorimetry. The results showed that before ischemia the cardiac functions of CoPP, ZnPP and control groups were stable, and there were no significant differences. After reperfusion, cardiac functions had significant differences among the three groups (P < 0.05). Compared with pre-ischemia, the cardiac function decreased and obvious cardiac arrest was shown in control and ZnPP groups, while the cardiac function in CoPP group did not change significantly, maintaining a relatively stable level. At the same time, three groups' carbon monoxide level, myocardial enzymology and the cardiac function recovery time after reperfusion also had significant differences (P < 0.05). Compared with those in control group, recovery after reperfusion was faster, activities of creatine kinase and lactic dehydrogenase were significantly decreased, plasma CO and myocardial cGMP contents were significantly increased in CoPP group, while these changes were completely opposite in ZnPP group. It is concluded that endogenous carbon monoxide can maintain cardiac function, shorten the time of cardiac function recovery, and play a protective role in cardiac ischemia-reperfusion.

[Intervention of Tibetan medicine--twenty wei chenxiang pill on elevation of hypoxic pulmonary arterial pressure in rats].

OBJECTIVE: To investigate the role of Tibetan medicine-Twenty Wei Chenxiang Pill interfering with serum ET-1 level, in order to confirm that ET-1 is involved to the pathogenesis of hypoxic pulmonary hypertension. METHODS: 165 Wistar rats were randomly divided into high altitude control group,Tibetan medicine-Twenty Wei Chenxiang Pill group and plain control group. The physiological signal acquisition system was used to record pulmonary arterial pressure, and RV/(LV + S) ratio were caculated. Serum HIF-1alpha and ET-1 protein levels were determined by the method of ELISA, and ETA protein levels in lung tissue were determined by Western Blot method. RESULTS: Compared with the high altitude group,in the rats of Tibetan medicine-Twenty Wei Chenxiang Pill group,the pulmonary arterial pressure decreased significantly from the seventh day and the seventh day (P < 0.01), the RV/(LV + S) ratio and serum HIF-1alpha levels decreased significantly from the third day (P < 0.05 or P < 0.01), the serum ET-1 levels decreased significantly from the third day (P < 0.05 or P < 0.01), and the expression of ETA protein decreased significantly from the beginning (P < 0.01 or P < 0.001). CONCLUSION: ET-1 is one of the important factors causing pulmonary artery pressure increasing and right ventricular wall thickening, which plays a role in hypoxic pulmonary artery only involved in the early period hypoxia, but not in the later period. Tibetan medicine--twenty Wei Chenxiang Pill can prevent the pulmonary artery hypertension and the right ventricular wall thickening in rats, and its mechanism may be related to the direct inhibition of ET-1 and protein levels of ETA or the indirect downregulation of ET-1 level and ETA through inhibition of HIF-la level.

Associations between interleukin-1 polymorphisms and gastric cancers among three ethnicities.

AIM: To investigate the associations between interleukin (IL)-1B and IL-1RN polymorphisms and gastric cancers among the Tibet, Hui and Han ethnicities. METHODS: Genomic DNA was extracted from peripheral blood of 210, 205, and 202 healthy volunteers and from 155, 158, and 197 gastric cancer patients from the Tibet, Hui, and Han populations, respectively. Polymorphisms in IL-1B and IL-1RN were analyzed by denaturing high-performance liquid chromatography. RESULTS: Carriers of the IL-1B-31 CC genotype had an increased risk of intestinal type gastric cancer [odds ratio (OR) = 2.17, P = 0.037] in the Tibet ethnicity. Carriers of the IL-1B 2/L genotype had an increased risk of both intestinal and diffuse types of gastric cancer (OR = 2.08, 2.31, P = 0.007, 0.016, respectively) in the Hui ethnicity. In the Han population, carriers of the IL-1B-31 CC, IL-1B-511CT, TT genotypes had increased risk of intestinal type gastric cancer (OR = 2.51, 2.74, 5.66, P = 0.005, 0.002, 0.000, respectively). CONCLUSION: IL-1B and IL-RN genotypes may differentially contribute to gastric cancer among the Tibet, Hui, and Han ethnicities in the Qinghai area of China.