Comparative Effect of Atomoxetine versus Formoterol on Dexamethasone-Induced Skeletal Muscle Atrophy in Male Mice

Atrophy of skeletal muscles is still one of numerous diseases' clinical problems. Formetrol, an agonist of the B adrenergic receptor, may prevent this atrophy. An FDA-approved inhibitor of reuptake of norepinephrine called atomoxetine was effective in preventing skeletal muscle atrophy.
Aim of work: This study aimed to compare the effect of atomoxetine versus formetrol on dexamethasone-induced skeletal muscle atrophy in male mice.
Material and methods:
Forty-eight adult male albino mice were divided into six groups (8 mice each): Group I (control group) Group 2 (dexamethasone treated group), Group 3 (atomoxetine only treated group), Group 4 (atomoxetine + dexamethasone treated group), Group 5 (formetrol only treated group) Group 6 (formetrol + dexamethasone treated group).Sections were stained with hematoxylin and eosin stain & Picro Sirius red (PSR) histochemical reaction. Immunohistochemical reaction was done using nuclear factor kappa-B (NF-KB) and heat shock protein (Hsp70) antibodies. The area percentage of collagen fibers deposition, area percent of nuclear factor kappa-B immunoexpression, area percentage of heat shock protein 70 immunoexpression and the diameter of muscle fiber were measured by comp image analaysis.
Results: Group 2 (dexamethasone treated group) showed decrease in diameter of muscle fibers. Group 4 (atomoxetine and dexamethasone treated group) and Group 6 (formetrol and dexamethasone treated group) showed increase in diameter of muscle fibers as compared to dexamethasone group.
Conclusion: Formetrol (β2-AR) treatment induced skeletal muscle hypertrophy while, atomoxetine doesnot stimulate skeletal muscle hypertrophy, so it has a potential in the prevention of skeletal muscle atrophy.