RESUMO
Acute myocardial infarction (AMI) has become the leading cause of death in cardiovascular diseases. Myocardial ischemia and reperfusion (MI/R) occurs when myocardial blood circulation is reconstructed after blood supply is limited or lack, often after myocardial infarction, and is the main cause of acute myocardial injury. According to the length of ischemia time, arrhythmia, myocardial inhibition, and myocardial infarction may occur in sequence in MI/R. Mitochondria are the key organelles involved in MI/R injury. Mitochondrial ROS eruption, Ca2+ imbalance, mPTP opening, mitochondrial swelling, and release of pro-apoptotic proteins all lead to mitochondrial dysfunction and myocardial function impairment. Exercise is an effective intervention to prevent myocardial ischemia-reperfusion injury, and its protective effect is closely related to the intensity of exercise, the length of exercise time, the type of exercise and the internal exercise ability. The mitochondrial mechanism of exercise protection against myocardial ischemia-reperfusion injury is determined by many factors. During reperfusion, the heart after trained is better able to maintain energy homeostasis, maintain ΔΨm and limit mPTP activation, maintain ATP synthesis. Activation of the sarcoKATP and/or mitoKATP channels by exercise induces cellular and/or myocardial hyperpolarization, protecting the mitochondria and myocardium during MI/R. Exercise-trained hearts can regulate calcium homeostasis during MI/R and limit mitochondrial Ca2+ overload. Exercise training can improve the activity of mitochondrial antioxidant enzymes to clear ROS and regulate mitochondrial Ca2+ concentration during MI/R. Exercise can increase the bioavailability of NO near mitochondria and indirectly achieve exercise-induced myocardial protection through protein S-nitrosylation and the eNOS-NO pathway is related to mitochondrial biogenesis after exercise training. Exercise training can also affect mitochondrial dynamics during MI/R by preventing mitochondrial division and promoting mitochondrial fusion. Exercise training can promote autophagy of damaged mitochondria and reduces apoptosis through mitochondria too, thus helping to maintain the function of mitochondrial bank. Besides these, exercise training leads to the production of motor factors (mainly from the muscles, but also from the brain, red blood cells, and other tissues) that contribute to remote regulation of the heart. This paper reviews the mitochondrial mechanism of MI/R, the protective effect of exercise on MI/R and the role of mitochondria in it, in order to provide more theoretical basis and new therapeutic targets for the diagnosis and treatment of heart disease, and provide new targets for drug research and development. In future clinical treatment, it is expected that sports pills targeted mitochondria can treat MI/R injury for bedridden people who cannot exercise or people who do not want to exercise through new technological means such as nanoparticle packaging.
RESUMO
At present, the incidence of overweight and obesity has reached epidemic levels worldwide, which call a challenge to the prevention and control of chronic metabolic diseases. Because obesity is a major risk factor for a range of metabolic diseases, including type 2 diabetes (T2DM), non-alcoholic fatty liver disease (NAFLD), cardiovascular and neurodegenerative diseases, sleep apnea, and some types of cancer. However, the drugs remain limited. Therefore, there is an urgent need to develop effective long-term treatments to address obesity-related complications. Fibroblast growth factor 1 (FGF1) is an important regulator of systemic energy homeostasis, glycolipid metabolism and insulin sensitivity. FGF1 is a non-glycosylated polypeptide consisting of 155 amino acids, consisting of 12 inverted parallel β chains with amino and carboxyl terminus, and N-terminus extending freely without the typical secretory signaling sequence, closely related to its own biological activity. Thus, FGF1 mutants or derivatives with different activities can be designed by substitution or splicing modification at theN-terminal. FGF1 plays an irreplaceable role in the development, deposition and function of fat. High-fat diet can regulate available FGF1 through two independent mechanisms of nutritional perception and mechanical perception, and influence the function of fat cells. FGF1 controls blood glucose through peripheral and central effects, enhances insulin sensitivity, improves insulin resistance, and plays a role in diabetic complications, which is expected to become a new target for the treatment of T2DM in the future. FGF1 may be involved in the regulation of NAFLD from mild steatosis to severe non-alcoholic steatohepatitis. FGF1 is closely related to the occurrence and development of a variety of cancers, improve the efficacy of anti-cancer drugs, and play a direct and indirect anti-cancer role. In addition, FGF1 plays an important role in the occurrence and development of the cardiovascular system and the improvement of cardiovascular diseases such as ischemia/reperfusion injury, myocardial infarction, pathological cardiac remodeling, cardiotoxicity. Therefore, FGF1 shows a number of therapeutic benefits in the treatment of obesity and obesity-related complications. But because FGF1 has strong mitotic activity and long-term use has been associated with an increased risk of tumorigenesis, its use in vivo has been limited and enthusiasm for developing it to treat obesity-related complications has been dampened. However, FGF1 was found to induce cell proliferation primarily through FGFR3 and FGFR4, but its metabolic activity was mainly mediated by FGFR1. That is, FGF1 activity that promotes mitosis and anti-obesity-related complications appears to be separable. Currently, many engineered FGF1 variants have been developed, such as FGF1ΔHBS, MT-FGF1ΔHBS, FGF1∆NT, ∆nFGF1, FGF1R50E. Although the effect of FGF1 or its analogues on obesity-related complications has been demonstrated in many rodent studies, there are no relevant clinical results. This may be due to the unknown safety and therapeutic efficacy of FGF1 in large animals and humans, as well as concerns about tumorigenesis that hinder its development into a lifelong therapeutic agent. This review summarizes recent advances in the development of FGF1-based biologic drugs for the treatment of obesity-related complications, highlights major challenges in clinical implementation, and discusses possible strategies to overcome these obstacles.
RESUMO
OBJECTIVE@#To apply hypoxia of different oxygen concentration on C2C12 cells to study the changes of Nrf2 antioxidant system under HO.@*METHODS@#The perfect simulative effect time and concentration of HO were chosen. Cell vitality was tested after C2C12 cells cultured in 0.1 mmol/L, 0.25 mmol/L, 0.5 mmol/L, 0.75 mmol/L, 1 mmol/L and 2 mmol/L HO for 1 or 2 h respectively. The C2C12 cells were divided into different oxygen concentration group: 21%O, 12%O, 8%O, 5%O respectively. And then cells were treated with HO for 1 h, and collected for determination. Immunofluorescence of Nrf2 and the protein expression of Nrf2 were detected. The expressions of antioxidant enzymes superoxide dismutase 1 (SOD1), superoxide dismutase 2 (SOD2), catalase(CAT), NADPH quinine oxidoreductase-1 (NQO-1), glutathione peroxidase-1 (GPX-1), Heme oxygenase-1 (HO-1) mRNA and cellular ROS levels were tested by high quality fluorescence assay.@*RESULTS@#0.5 mmol/L HO for 1 h was selected as the conditions of HOstimulation. Compared with 21% O group, the expressions of Nrf2 mRNA and protein, antioxidant enzymes SOD1, SOD2, CAT, HO-1, NQO-1, GPX-1 mRNA were increased significantly (P＜0.05 or P＜0.01), and ROS level was lower (P＜0.01) in 12%O group cells; only the expression of GPX-1 mRNA was increased (P＜0.05) in 8%O group; the expressions of Nrf2 mRNA and protein expression, antioxidant enzymes SOD1, SOD2, NQO-1, GPX-1 mRNA were decreased significantly(P＜0.05 or P＜0.01), and ROS level was higher (P＜0.01) in 5%O group.@*CONCLUSION@#Hypoxia can affect the Nrf2 antioxidant system, and the different oxygen concentrations have different impact. In addition, 12% O for 12 h could promote the Nrf2 antioxidant system, and 5% extremely low oxygen may inhibit it.