Trace element movement and oxidative stress in skeletal muscle atrophied by immobilization

Abstract

The movements of trace elements and the level of oxidative stress in the soleus, a typical slow red muscle which, atrophied by immobilization, were investigated in designated intervals. Male Wistar rats (14 wk old) whose one ankle joints were immobilized in the extended position were killed after 4, 8, and 12 days. Fe, Zn, Mn, and Cu concentrations and the levels of thiobarbituric acid-reactive substance (TBARS) and glutathione were measured. The rate of atrophy increased rapidly until the 8th day and slowly after that. In whole muscle, Fe concentration kept increasing, and Zn and Mn increased temporarily. Their subcellular distributions also changed; especially, the Fe level of the microsomal fraction kept increasing and reached threefold at 12 days. Increased TBARS and glutathione disulfide and decreased total glutathione indicated the increased oxidative stress in atrophy, which might result from an increased Fe level, especially that of the microsomal fraction. Vitamin E injection lessened the rate of atrophy, which showed that oxidative stress accelerated muscle atrophy. This might be mediated by increased intracellular Ca. Also metallothionein was induced in muscle atrophy.

Effect of Molecular Hydrogen Saturated Alkaline Electrolyzed Water on Disuse Muscle Atrophy in Gastrocnemius Muscle

“…On the other hand, in the previous work of Kondo (2000), an increased TBARS level in atrophied soleus muscle after 12-day immobilization was observed. The disparity may be due to different experimental models (immobilization vs. unweighting) and period, as well as differences in muscle fiber susceptibility (soleus vs. gastrocnemius) to oxidative stress (Hollander et al, 1998;Kondo et al, 1992;Kondo, 2000). But the reasons for this disparity are still unclear and warrant further studies.…”

Oxidative stress during recovery from muscle atrophy

“…Taking into account the catalytic action of the increased iron in atrophied muscle, we predicted that oxygen radicals might increase during the recovery from muscle atrophy [4]. In the present investigation, we measured some parameters of oxidative stress, such as TBARS and GSSG, and examined the effect of vitamin E on the recovery from atrophy.…”

“…with the soleus muscle in a shortened position), as described previously [2]. The procedure for limb-immobilization, as such, had no significant effects [4].…”

“…We have found an increased iron level, especially in the microsomal fraction, in skeletal muscle atrophied by immobilization, and have suggested the possibility that increased iron may be responsible for the enhanced oxidative stress in atrophied muscle [4,5]. The role of iron has, since, been confirmed by the use of deferoxamine, an iron-chelating agent, which was shown to suppress the increased oxidative stress [6].…”

Denervation-induced skeletal muscle atrophy is associated with increased mitochondrial ROS production

“…Several potential contributing factors in loss of muscle mass have been identified, including neuromuscular alterations, changes in protein synthesis and degradation, and loss of fibers due to apoptosis (15,52,58). Oxidative stress and mitochondrial dysfunction have also been implicated in sarcopenia (27,62), hindlimb unloading (3,46,65), and in atrophic mouse muscle from amyotrophic lateral sclerosis (ALS) transgenic mice (54). Because mitochondria are an important source of reactive oxygen species (ROS) in cells, we were interested in delineating the role of muscle mitochondrial ROS generation in muscle atrophy.…”