ABSTRACT
BACKGROUND:It is unclear whether hydrogen-rich water can be used to protect skeletal muscle injury induced by eccentric exercise, as wel as the relative mechanism. OBJECTIVE:To observe the effect of hydrogen-rich water on the mitochondrial oxidative stress and inflammation in rat skeletal muscle after eccentric exercise, and to investigate the relative signaling pathway of hydrogen-rich water. METHODS:Forty Sprague Dawley rats were randomly divided into four groups: control group, eccentric exercise group, eccentric exercise+saline group, and eccentric exercise+hydrogen-rich water group. Rats in three eccentric exercise groups were exercised on a motor-driven rodent treadmil at a speed of 16-18 m/min and a slope of-16° for 90 minutes per day. Rats in the eccentric exercise+hydrogen-rich water group were subjected to intraperitoneal injection of hydrogen-rich water (10 mL/kg) immediately after exercise; and rats in the eccentric exercise+saline group were administrated with normal saline after exercise. Al the interventions lasted for 5 days. RESULTS AND CONCLUSION:Hydrogen-rich water intervention after eccentric exercise could markedly enhance the mitochondrial Sirtuin-3 expression, improve the mitochondrial membrane potential and activity of manganese superoxide dismutase, down-regulate the mitochondrial reactive oxygen species generation and mitochondrial DNA oxidative damage, thus inhibiting inflammatory cytokines expression, such as NLRP3 and interleukin-1β. The results indicated that hydrogen-rich saline could directly scavenge reactive oxygen species. In addition, hydrogen-rich water could improve mitochondrial energy metabolism and antioxidant capacity through up-regulation of Sirtuin-3, which in turn inhibits eccentric exercise-induced mitochondrial oxidative stress and secondary inflammation in the skeletal muscle.
ABSTRACT
BACKGROUND: Ischemic preconditioning (IPC) can induce endogenous protection mechanism, which effectively prevent ischemia/reperfusion injury following organ transplantation. Cold and warm ischemia may induce ischemia/reperfusion injury of pancreas transplantation, and apoptosis of pancreatic acinar cells is one of the important reasons of pancreas graft functional defect after transplantation. Mitochondrial DNA has repair system, and its balance with mitochondrial DNA injury influences disease occurrence and outcome.OBJECTIVE: To observe the effect of IPC on apoptosis of transplanted pancreatic acinar cells, and the possible role of reactive oxygen (ROS) and mitochondrial DNA repair enzyme.METHODS: A total of 50 health, male, Sprague-Dawley rats were randomly divided into three groups: sham operated (n = 10), donors (n = 20) and recipients (n = 20). The recipients were randomly divided into ischemia/reperfusion group (IR, n = 10) and IPC group (n = 10). The sham operated group was subjected to abdominal open and close operation. IR group and IPC group received establishment of diabetic model by streptozotocin injection. IR rats received whole pancreatic-duodenal transplantation alone. IPC rats received whole pancreatic-duodenal transplantation exposed ischemic preconditioning with 5 minutes ischemia and 5 minutes reperfusion twice. All grafts were keep with warm ischemia time 15 minutes and cold ischemia (in 4 ℃ UW preservation solution) time 180 minutes. Twelve hours after reperfusion, serum amylase, blood glucose, Caspase-3, -9 activity were detected. Pancreatic acinar cell apoptosis was measured by flow cytometry. Mitochondrial cross-membrane potential (Δψ) was measured by monitoring the fluorescence spectrum of rhodamine 123. Mitochondrial H2O2 generation was determined using dichlorofluorescein as a probe. 8-oxodG in mitochondrial DNA (mtDNA) was measured with HPLC system. Release of cytochrome C, phosphorylation of Akt and mitochondrial OGG1 protein expression were determined by Western-blotting. RESULTS AND CONCLUSION: The ischemia preconditioning can relieve the pancreatic acinar cell apoptosis in pancreas graft and relieve IR injury by decreasing mitochondrial oxidative stress, mtDNA injury, and increasing phosphorylation of Akt and mitochondrial OGG1 expression.
ABSTRACT
Objective To explore the structure of ribosomal protein S7 ( RPS7) gene of giant panda ( Ailuropoda melanoleuca) and investigate its homologies with other already reported sequences,including Homo sapiens,Mus musculus,Rattus norvegicus and Bos taurus. Methods The cDNA of RPS7 was cloned from the giant panda by RT-PCR. The sequence data were analyzed by GenScan software. Blast 2. 1 was used to study the homology of the obtained RPS7 sequence with the gene sequences of other species; Open reading frame ( ORF) of the DNA sequence was searched using ORF finder software; Protein structure of the RPS7 sequence cloned was deduced using Predict Protein software. Results The full length of the sequence fragment was 589 bp containing an ORF of 585 bp. The deduced protein sequence showed that the protein was composed of 194 ami- no acids and its estimated molecular weight was 22. 126 85 ?103 with a pI of 10. 09. There were 7 different pat- terns of functional sites: one N-glycosylation site; two cAMP and cGMP-dependent kinase phosphorylation sites; four casein kinase C phosphorylation sites; one casein kinase Ⅱ phosphorylation site; two N-myristoylation sites; two amidation sites and one ribosomal protein S7e signature site in the RPS7 protein. Further analysis indicated that the sequence of RPS7 and the protein encoded were highly homologous to some mammals reported.Conclusion The complete coding sequence of RPS7 gene has been cloned through RT-PCR successfully, which is the first report on the RPS7 gene from the giant panda.