TianmaGouteng yin attenuates ischemic stroke-induced brain injury by inhibiting the AGE/RAGE pathway

Background:Ischemic stroke is characterized by permanent or transient obstruction of blood flow,leading to a growing risk factor and health burden.Tianmagouteng yin(TMG)is commonly used in Chinese medicine to treat cerebral ischemia.The aim of this study was to investigate the neuroprotective effects of TMG against ischemic stroke.Methods:Either permanent middle cerebral artery occlusion(pMCAO)or sham operation was performed on anesthetized Wistar male rats(n=36).Results:Results demonstrated that TMG administration reduced the infarction volume and mitigated the neurobehavioral deficits.Hematoxylin and eosin(HE)staining and Prussian blue staining revealed that TMG attenuated tissue disruption and microbleeds in hippocampus tissues.In addition,TMG down-regulated the receptor of advanced glycation end products(RAGE)and p-JAK2.It also inhibited the concentrations of advanced glycation end products(AGEs),ferritin,malondialdehyde(MDA),and reactive oxygen species(ROS).Conclusion:As repetitive clinical trials of neuroprotectants targeting stroke have failed previously,our results suggested that the natural product,TMG,can probably help in the vicious cycles of ischemic stroke pathology.

Anti-diabetic potential of apigenin,luteolin,and baicalein via partially activating PI3K/Akt/GLUT-4 signaling pathways in insulin-resistant HepG2 cells

Dietary flavonoids are abundant in natural plants and possess multiple pharmacological and nutritional activities.In this study,apigenin,luteolin,and baicalein were chosen to evaluate their anti-diabetic effect in high-glucose and dexamethasone induced insulin-resistant(IR)HepG2 cells.All flavonoids improves the glucose consumption and glycogen synthesis abilities in IR-HepG2 cells via activating glucose transporter protein 4(GLUT4)and phosphor-glycogen synthase kinase(GSK-3β).These fl avonoids signifi cantly inhibited the production of reactive oxygen species(ROS)and advanced glycation end-products(AGEs),which were closely related to the suppression of the phosphorylation form of NF-κB and P65.The expression levels of insulin receptor substrate-1(IRS-1),insulin receptor substrate-2(IRS-2)and phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)pathway in IR-HepG2 cells were all partially activated by the fl avonoids,with variable effects.Furthermore,the intracellular metabolic conditions of the fl avonoids were also evaluated.

Food-advanced glycation end products aggravate the diabetic vascular complications via modulating the AGEs/RAGE pathway

The aim of this study was to investigate the effects of high-advanced glycation end products （AGEs） diet on diabetic vascular complications. The Streptozocin （STZ）-induced diabetic mice were fed with high-AGEs diet. Diabetic characteristics, indicators 3f renal and cardiovascular functions, and pathohistology of pancreas, heart and renal were evaluated. AGEs/RAGE/ROS pathway parameters were determined. During the experiments, the diabetic mice exhibited typical characteristics including weight loss, polydipsia, polyphagia, polyuria, high-blood glucose, and low-serum insulin levels. However, high-AGEs diet effectively aggravated these diabetic sharacteristics. It also increased the 24-h urine protein levels, serum levels of urea nitrogen, creatinine, c-reactive protein （CRP）, low density lipoprotein （LDL）, tumor necrosis factor-a （TNF-a）, and interleukin-6 （IL-6） in the diabetic mice. High-AGEs diet deteriorated the histology of pancreas, heart, and kidneys, and caused structural alterations of endothelial ceils, mesangial cells and podocytes in renal ：ortex. Eventually, high-AGEs diet contributed to the high-AGE levels in serum and kidneys, high-levels of reactive oxygen species ＇,ROS） and low-levels of superoxide dismutase （SOD） in serum, heart, and kidneys. It also upregulated RAGE mRNA and protein expression in heart and kidneys. Our results showed that high-AGEs diet deteriorated vascular complications in the diabetic mice. The activation of AGEs/RAGE/ROS pathway may be involved in the pathogenesis of vascular complications in diabetes.