scholarly journals Antioxidant Apigenin Relieves Age-Related Muscle Atrophy by Inhibiting Oxidative Stress and Hyperactive Mitophagy and Apoptosis in Skeletal Muscle of Mice

2020 ◽  
Vol 75 (11) ◽  
pp. 2081-2088
Author(s):  
Dongtao Wang ◽  
Yajun Yang ◽  
Xiaohu Zou ◽  
Jing Zhang ◽  
Zena Zheng ◽  
...  

Abstract Skeletal muscle atrophy in the aged causes loss in muscle mass and functions. Naturally occurring antioxidant flavonoid apigenin is able to ameliorate obesity- and denervation-induced muscle atrophies, but its effects on age-related muscle atrophy remain unknown. We hypothesized that apigenin can relieve muscle atrophy in aged mice, probably through special effects on reactive oxygen species and enzymes with antioxidant functions. For the male mice of the study, apigenin showed significant dose-dependent effects in relieving aging-related muscle atrophy according to results of frailty index as indicator of frailty associated with aging, grip strength, and running distance. Apigenin also improved myofiber size and morphological features and increased mitochondria number and volume, as manifested by succinate dehydrogenase staining and transmission electron microscopy. Our tests also suggested that apigenin promoted activities of enzymes such as superoxide dismutase and glutathione peroxidase for antioxidation and those for aerobic respiration such as mitochondrial respiratory enzyme complexes I, II, and IV, increased ATP, and enhanced expression of genes such as peroxisome proliferator-activated receptor-γ coactivator 1α, mitochondrial transcription factor A, nuclear respiratory factor-1, and ATP5B involved in mitochondrial biogenesis. The data also suggested that apigenin inhibited Bcl-2/adenovirus E1B 19kD-interacting protein 3 and DNA fragmentation as indicators of mitophagy and apoptosis in aged mice with skeletal muscle atrophy. Together, the results suggest that apigenin relieves age-related skeletal muscle atrophy through reducing oxidative stress and inhibiting hyperactive autophagy and apoptosis.

2013 ◽  
Vol 115 (11) ◽  
pp. 1618-1625 ◽  
Author(s):  
Chounghun Kang ◽  
Li Li Ji

Prolonged immobilization (IM) results in skeletal muscle atrophy accompanied by increased reactive oxygen species (ROS) generation, inflammation, and protein degradation. However, the biological consequence of remobilizing such muscle has been studied only sparsely. In this study, we examined the peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α)-controlled mitochondrial biogenesis pathway and inflammatory response in mice subjected to 2 wk of hindlimb IM followed by 5 days of remobilization (RM). We hypothesized that ROS generation and activation of redox-sensitive signaling pathways play important roles in the etiology of muscle injury. FVB/N mice (age 2 mo) were randomly assigned to either 14 days of IM by casting one of the hindlimbs ( n = 7), IM followed by 5 days of RM with casting removed ( n = 7), or to a control group (Con; n = 7). Muscle to body weight ratios of three major leg muscles were significantly decreased as a result of IM. Two ubiquitin-proteasome pathway enzymes, muscle atrophy F-box (MAFb or atrogin-1) and muscle ring finger-1 (MuRF-1), were upregulated with IM and maintained at high levels during RM. Protein contents of PGC-1α and nuclear respiratory factors 1 and 2 in tibialis anterior (TA) muscle were reduced by 50% ( P < 0.01) in IM vs. Con, with no recovery observed during RM. IM suppressed mitochondrial transcription factor A and cytochrome- c content by 57% and 63% ( P < 0.01), respectively, and cytochrome- c oxidase activity by 58% ( P < 0.05). Furthermore, mitochondrial DNA content was reduced by 71% ( P < 0.01) with IM. None of these changes were reversed after RM. With RM, TA muscle showed a 2.3-fold ( P < 0.05) higher H2O2 content and a 4-fold ( P < 0.01) higher 8-isoprostane content compared with Con, indicating oxidative stress. Tumor necrosis factor-α and interleukin-6 levels in TA muscle were 4- and 3-fold higher ( P < 0.05), respectively, in IM and RM vs. CON. The nuclear factor-κB (NF-κB) pathway activation was observed only after RM, but not after IM alone. These data indicate an increase in ROS generation during the initial phase of muscle RM that could activate the NF-κB pathway, and elicit inflammation and oxidative stress. These events may hinder muscle recovery from IM-induced mitochondrial deterioration and protein loss.


2009 ◽  
Vol 106 (6) ◽  
pp. 2049-2059 ◽  
Author(s):  
Annabelle Z. Caron ◽  
Geneviève Drouin ◽  
Justine Desrosiers ◽  
Frédéric Trensz ◽  
Guillaume Grenier

Skeletal muscle atrophy is a serious concern for patients afflicted by limb restriction due to surgery (e.g., arthrodesis), several articular pathologies (e.g., arthralgia), or simply following cast immobilization. To study the molecular events involved in this immobilization-induced debilitating condition, a convenient mouse model for atrophy is lacking. Here we provide a new immobilization procedure exploiting the normal flexion of the mouse hindlimb using a surgical staple to fix the ventral part of the foot to the distal part of the calf. Histological analysis revealed that our approach induced significant skeletal muscle atrophy by reducing the myofiber size of the tibialis anterior (TA) muscle by 36% compared with the untreated contralateral TA within a few days postimmobilization. Two molecular markers for atrophy, atrogin-1/muscle atrophy F-box (atrogin-1/MAFbx) and muscle ring finger 1 (MuRF-1) mRNAs, were significantly upregulated by 1.9- and 5.9-fold, respectively. Interestingly, our model also revealed the presence of an early inflammatory process during atrophy, characterized by the mRNA upregulation of TNF-α, IL-1, and IL-6 (1.9-, 2.4-, and 3.4-fold, respectively) simultaneously with the upregulation of the common leukocyte marker CD45 (6.1-fold). Moreover, muscle rapidly recovered on remobilization, an event associated with significantly increased levels of uncoupling protein-3 and peroxisome proliferator-activated receptor γ coactivator-1α mRNA, key components of prooxidative muscle metabolism. This model offers unexpected new insights into the molecular events involved in immobilization atrophy.


2018 ◽  
Vol 315 (5) ◽  
pp. C609-C622 ◽  
Author(s):  
Avisek Majumder ◽  
Mahavir Singh ◽  
Jyotirmaya Behera ◽  
Nicholas T. Theilen ◽  
Akash K. George ◽  
...  

Although hyperhomocysteinemia (HHcy) occurs because of the deficiency in cystathionine-β-synthase (CBS) causing skeletal muscle dysfunction, it is still unclear whether this effect is mediated through oxidative stress, endoplasmic reticulum (ER) stress, or both. Nevertheless, there is no treatment option available to improve HHcy-mediated muscle injury. Hydrogen sulfide (H2S) is an antioxidant compound, and patients with CBS mutation do not produce H2S. In this study, we hypothesized that H2S mitigates HHcy-induced redox imbalance/ER stress during skeletal muscle atrophy via JNK phosphorylation. We used CBS+/−mice to study HHcy-mediated muscle atrophy, and treated them with sodium hydrogen sulfide (NaHS; an H2S donor). Proteins and mRNAs were examined by Western blots and quantitative PCR. Proinflammatory cytokines were also measured. Muscle mass and strength were studied via fatigue susceptibility test. Our data revealed that HHcy was detrimental to skeletal mass, particularly gastrocnemius and quadriceps muscle weight. We noticed that oxidative stress was reversed by NaHS in homocysteine (Hcy)-treated C2C12 cells. Interestingly, ER stress markers (GRP78, ATF6, pIRE1α, and pJNK) were elevated in vivo and in vitro, and NaHS mitigated these effects. Additionally, we observed that JNK phosphorylation was upregulated in C2C12 after Hcy treatment, but NaHS could not reduce this effect. Furthermore, inflammatory cytokines IL-6 and TNF-α were higher in plasma from CBS as compared with wild-type mice. FOXO1-mediated Atrogin-1 and MuRF-1 upregulation were attenuated by NaHS. Functional studies revealed that NaHS administration improved muscle fatigability in CBS+/−mice. In conclusion, our work provides evidence that NaHS is beneficial in mitigating HHcy-mediated skeletal injury incited by oxidative/ER stress responses.


2018 ◽  
Vol 9 (1) ◽  
Author(s):  
Jie Yin ◽  
Lele Yang ◽  
Yangli Xie ◽  
Yan Liu ◽  
Sheng Li ◽  
...  

2020 ◽  
Vol 221 ◽  
pp. 44-57 ◽  
Author(s):  
Lemuel A. Brown ◽  
Steve D. Guzman ◽  
Susan V. Brooks

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