ABSTRACT
Aim To investigate the role of PPARβ and nitrative stress in human umbilical vein endothelial cells(HUVECs)injury induced by high glucose.Methods The cell viability was detected by CCK-8.The cell proliferation was detected by EdU proliferation detection kit.The protein expression level of PPARβ,eNOS,iNOS,and 3-nitrotyrosine was detected by Western blot.The content of peroxynitrite and nitric oxide(NO)was determined by peroxynitrite kit and Griess Reagent,respectively.Results Glucose(30,40,50 mmol·L-1)significantly reduced the cell viability of HUVECs in a dose-dependent manner.Glucose at 30 mmol·L-1(high glucose,HG)significantly reduced the proliferation of HUVECs,down-regulated the expression of PPARβ,eNOS at protein level and NO content,and increased iNOS,3-nitrotyrosine protein expression and peroxynitrite level.The above effects of HG were reversed by PPARβ agonist GW0742(1 μmol·L-1).Both PPARβ antagonist GSK0660(1 μmol·L-1)and NOS inhibitor L-NAME(10 μmol·L-1)blocked the protective effects of GW0742.Conclusion The down-regulation of PPARβ is involved in the injury of HUVECs induced by high glucose,which may be mediated,at least partly,by the stimulation of nitrative stress.
ABSTRACT
Transient receptor potential ankyrin 1 (TRPA1) is a family member of the transient receptor potential (TRPs). It is primarily localized to a subpopulation of primary sensory neurons, such as trigeminus, vagus and dorsal root ganglia. Neuropathic pain is often caused by peripheral nerve injury, diabetes and chemotherapeutics. A large of oxidative/nitrative stress products are produced during neuropathic pain, which cause acute nociception, allodynia, and hyperalgesia. TRPA1 antagonists may be beneficial in the treatment of neuropathic pain. Here, the role of TRPA1 in neuropathic pain is summarized.
ABSTRACT
Background Trans-arachidonic acids (TAAs) are specific lipid markers of nitrative stress and the major products of NO2·-mediated ismoerization of aracchidonic acid(AA),and they represent a possible new mechanism of NO2·-induced toxicity in ischemic retinopathy.Our previous study demonstrated that high glucose induce nitrative stress response. Objective This study aimed to evaluate the effect of nitrative stress on retinal capillary in diabetic rats by detecting the TAAs with gas chromatography and mass spectrometry(GC/MS).Methods One hundred 2-week-old clean male SD rats were randomly divided into control group and diabetic group.Diabetic rat models were induced by intraperitoneal injection of streptozoticin of 60 mg/kg,and the successful models were identified as the blood glucose level>16.7 mmol/L.The synthesis method was modified in this study andaraehidonic acid w8$utilized as starting material.14E-AA was obtained as a standard sample via expoxidation and deoxidation in a safe and practical pattern.Serum TAAs and AA in diabetic rats were detected by GC/MS in 2,4,8,12 and 16 weeks after injection of streptozoticin.The ratio of peak area of TAAs to AA with selected ion of 79 was estimated and compared with normal rats. Results Fifty rats had been in Diabetic models were established in 50 rats with the successful rate 100%,and the high blood glucose level in model rats retained throughout the experimental duration.GC/MS results showed that the 14E-AA was obtained with the purity of 97.3%,which provided a standard sample to nitrative stress-related research as a premise. No significant differences were found in serum TAAs/AA values at 2 weeks and 4 weeks between model group and control group (t =-0. 376, t =-0. 642,P>0. 05). However,serum TAAs/AA values in at 8,12 and 16 weeks after streptozoticin injection were considerably elevated in comparison with those of control group (0. 0832 vs 0. 1042,0. 0910 vs 0. 1568, 0. 1100 vs 0. 1895;t=-36.409,t=-166.714,t=-148.212,P<0. 05). Conclusion Elevation of serum TAAs/AA is associated with diabetic duration,implying that damage of nitrative stress to retinal capillary is a parallel procedure to diabetic course.Establishment of GC/MS detection system offers a new evaluating indicator in the research on microvascular ischemic disease and could be implemented in clinical testing.