Aim To investigate whether necroptosis mediates chemical hypoxia-induced HT22 mouse hippocampal cell injury and inflammation.Methods HT22 hippocampal cells were exposed to cobalt chloride (CoCl2) to establish a model of the chemical hypoxia-induced injury and inflammation.The expression level of RIP3 (an index of necroptosis) was determined by Western blot.Cell counter kit-8 (CCK-8) assay was used to test the cell viability.Lactate dehydrogenase (LDH) activity in the culture medium was measured with commercial kits.Mitochondrial membrane potential (MMP) was examined by rhodamine123 staining followed by photofluorography.The intracellular level of reactive oxygen species (ROS) was detected by 2', 7'-dichlorfluorescein-diacetate (DCFH-DA) staining followed by photofluorography.The secretion levels of interleukin-1β (IL-1β) and tumor necrosis factor-a (TNF-α) were measured by ELISA.Results Treatment of HT22 hippocampal cells with 600 μmol·L-1 CoCl2 for 36 h markedly induced cytotoxicity, leading to a decrease in cell viability to (52.0±2.65) % , indicating that chemical hypoxia-induced cellular injury model was successfully set up.Besides, CoCl2 induced considerable injuries and inflammation, evidenced by increases in LDH activity, ROS production, MMP loss, as well as the secretion levels of IL-1β and TNF-α.Co-treatment of the cells with 40~100 μmol·L-1 Nec-1 (a specific inhibitor of necroptosis) and CoCl2 markedly attenuated the decrease in viability induced by CoCl2, reaching the best anti-cytotoxicity inhibitory effect at 80 μmol·L-1.Meanwhile, the co-treatment with 80 μmol·L-1 Nec-1 blocked the above injuries and inflammatory response induced by CoCl2.In addition, treatment of HT22 hippocampal cells for 6~48 h up-regulated the expression of RIP3, and Nec-1 alleviated the up-regulation of RIP3 expression level induced by CoCl2.Conclusion Necroptosis mediates chemical hypoxia-induced HT22 hippocampal cell injury and inflammation.

OBJECTIVETo study the hormonal and metabolic responses of fetal lamb during cardiopulmonary bypass.

METHODSSix pregnant ewes underwent fetal cardiopulmonary bypasses with artificial oxygenators and roller pumps for 30 minutes, which maintained the blood gas value at the fetal physiological level. The fetal blood pressure, heart rate, pH value and blood lactate levels were monitored. The levels of catecholamine, cortisol and insulin were measured pre-bypass and then again 30 minutes later. The blood glucose and free fatty acid levels were monitored continuously during the bypass. Fetal hepatic PAS staining was also carried out.

RESULTSThere were no changes before and during the bypass in fetal blood pressure, heart rate and blood gas. However, pH values decreased and blood lactate levels increased (P < 0.05). The fetal catecholamine and cortisol levels increased significantly (P < 0.01), while the levels of insulin did not change. The blood glucose and free fatty acid levels increased at the beginning of the bypass (P < 0.01), and then gradually slowed down during the bypass. The fetal hepatic PAS staining showed that hepatic glycogen was consumed in large amounts. After 30 minutes of bypass, the fetal lamb would not survive more than 1 hour.

CONCLUSIONThe fetal lamb has a strong negative reaction to cardiopulmonary bypass.

Animals ; Blood Gas Analysis ; Blood Glucose ; analysis ; Cardiopulmonary Bypass ; adverse effects ; Catecholamines ; blood ; Fatty Acids, Nonesterified ; blood ; Fetus ; physiology ; Hemodynamics ; physiology ; Hydrocortisone ; blood ; Lactates ; blood ; Sheep

BACKGROUNDNumerous studies have demonstrated that the peroxisome proliferator-activated receptor-γ (PPARγ) plays an important role in regulating endothelial progenitor cells (EPC) function. Telmisartan, as a partial agonist of PPARγ, may have an effect on the regulation of EPC functions. The purpose of this study was to investigate the effects of telmisartan on EPC proliferation and differentiation.

METHODSPeripheral blood derived mononuclear cells containing EPC were isolated from healthy volunteers and then cultured on fibronectin-coated dishes in the presence or absence of telmisartan. The proliferative activity of EPC was determined by colony forming units (CFU) and MTT assay. The migratory activity of EPC was assessed by transwell assay. The expression of endothelial cells (EC) markers, including vascular endothelial cadherin (VE-cadherin), von Willebrand factor (vWF) and endothelial nitric oxide synthase (eNOS), were measured by Western blotting analysis.

RESULTSMorphological analysis revealed that telmisartan significantly increased the proliferation of EPC and the number of endothelial cell colony forming units. Telmisartan could enhance the expression of the makers of mature EC, including VE-cadherin, vWF, and eNOS, which indicated telmisartan could stimulate EPC to differentiate into mature EC. Telmisartan increased the phosphorylation of Akt in EPC. The inhibition of Akt activation significantly attenuated the effect of telmisartan on EPC functions, suggesting that Akt is involved in the stimulatory effect of telmisartan on EPC differentiation.

CONCLUSIONSThe results of this study demonstrate that telmisartan promotes EPC functions via activation of Akt.

Benzimidazoles ; pharmacology ; Benzoates ; pharmacology ; Cell Differentiation ; drug effects ; genetics ; Cell Proliferation ; drug effects ; Cells, Cultured ; Endothelial Cells ; cytology ; Humans ; Proto-Oncogene Proteins c-akt ; genetics ; metabolism ; Stem Cells ; cytology ; drug effects