This study aimed to determine the effects of a single bout exercise on mitochondria-mediated apoptotic signaling in cardiac and skeletal muscles. Fischer 344 rats (4 months old) were randomly divided into the control or a single bout of exercise group (n=10 each). The rats performed a single bout of treadmill exercise for 60 min. Mitochondria-mediated apoptotic signaling (e.g., Bax, Bcl-2, mitochondrial permeability transition pore [mPTP] opening, cytochrome c, and cleaved caspase-3) was measured in cardiac (e.g., left ventricle) and skeletal (e.g., soleus and white gastrocnemius) muscles. A single bout of exercise significantly decreased mPTP opening sensitivity in all tissues. However, a single bout of exercise did not show any statistical differences in Bax, Bcl-2, cytochrome c, and cleaved caspase-3 in all tissues measured. A single bout of exercise did not show definite results on characteristics of mitochondria-mediated apoptotic signaling. Therefore, further research is necessary to provide a more mechanistic understanding of the apoptosis pathway.
Purpose: This study aimed to investigate the effects of single-bout exercise on mitochondria' function, dynamics (fusion, fission), and mitophagy in cardiac and skeletal muscles. Methods: Fischer 344 rats (4 months old) were randomly divided into the control (CON) or acute exercise (EX) group (n= 10 each). The rats performed a single bout of treadmill exercise for 60 minutes. Mitochondrial function (e.g.,O-2 respiration, H2O2 emission, Ca2+ retention capacity), mitochondria fusion (e.g., Mfnl, Mfn2, Opal), mitochondria fission (e.g., Drp1, Fis1), and mitophagy (e.g., Parkin, Pinkl, LC3II, Bnip3) were measured in permeabilized cardiac (e.g., left ventricle) and skeletal (e.g., soleus, white gastrocnemius) muscles. Results: Mitochondrial O-2 respiration and Ca2+ retention capacity were significantly increased in all tissues of the EX group compared with the CON group. Mitochondria H2O2 emissions showed tissue-specific results; the emissions showed no significant differences in the left ventricle or soleus (type I fibers) but was significantly increased in the white gastrocnemius (type II fibers) after acute exercise. Mitochondrial fusion and fission were not altered in any tissues of the EX group. Mitophagy showed tissue-specific differences: It was not changed in the left ventricle or white gastrocnemius, whereas Parkin and LC3II were significantly elevated in the soleus muscle. Conclusions: A single bout of aerobic exercise may improve mitochondrial function (e.g., O-2 respiration and Ca2+ retention capacity) in the heart and skeletal muscles without changes in mitochondrial dynamics or mitophagy.
Neuroinflammation is a central pathological feature of several acute and chronic brain diseases, including Alzheimer disease (AD), Parkinson disease (PD), amyotrophic lateral sclerosis (ALS), and multiple sclerosis (MS). It induces microglia activation, mitochondrial dysfunction, the production of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), pro-inflammatory cytokines, and reactive oxygen species. Exercise, which plays an important role in maintaining and improving brain health, might be a highly effective intervention for preventing neuroinflammation-related diseases. Thus, since exercise can improve the neuroimmune response, we hypothesized that exercise would attenuate neuroinflammation-related diseases. In this review, we will highlight (1) the biological mechanisms that underlie AD, PD, ALS, and MS, including the neuroinflammation pathways associated with microglia activation, NF-κB, pro-inflammatory cytokines, mitochondrial dysfunction, and reactive oxygen species, and (2) the role of exercise in neuroinflammation-related neurodegenerative diseases.
Aging is a risk factor for heart disease and heart failure, which result from a progressive impairment of cardiac functions, including stroke volume, cardiac output, blood flow, and oxygen consumption. Age-related cardiac dysfunction is associated with impaired cardiac structures, such as the loss of myocytes, structural remodeling, altered calcium (Ca2+) handling, and contractile dysfunction. However, the mechanism by which aging affects mitochondrial function in the heart is poorly understood. The purpose of this study was to determine the effects of aging on mitochondrial function in the rat heart. Male Fischer 344 rats were randomly assigned to very young sedentary (VYS, 1 month), young sedentary (YS, 4 months), middle-aged sedentary (MS, 10 months), and old sedentary (OS, 20 months) groups. mitochondrial complex protein levels and mitochondrial function (e.g., mitochondrial hydrogen peroxide (H2O2) emission and Ca2+ retention capacity) were analyzed in the left ventricle. Aging was associated with decreased levels of OXPHOS (oxidative phosphorylation) protein expression of complex I to IV in the function of the electron transport chain. Aging increased the mitochondrial H2O2 emitting potential in the heart. In contrast, mitochondrial Ca2+ retention capacity gradually decreased with age. These data demonstrate that aging impairs mitochondrial function in cardiac muscle, suggesting that mitochondrial dysfunction with aging may be a primary factor for aging-induced cardiac dysfunction in the heart.