Ferulic Acid Promotes Growth of Both Fast Glycolytic and Slow Oxidative Skeletal Muscles in Corticosteroid-Induced Rat Myopathy

Abstract
Background: Glucocorticoids (GCs) are wide spread anti-inflammatory supplementation associated with various side effects especially in long term administration. Currently, there is no universally accepted prophylactic treatment for patients commencing long-term steroids.
Aim of Study: This research aims to study the possible beneficial role of Ferulic Acid (FA), as a naturally existing antioxidant and anti-inflammatory, in preventing muscle atrophy and promoting growth of fast glycolytic and slow oxidative skeletal muscle fibers in rat model of glucocorticoid induced myopathy.
Material and Methods: 48 rats were divided into 4 groups: Control, Ferulic acid supplemented group, Dexamethasone (Dex) supplemented group, rats supplemented with FA and Dex. After 2 weeks, all rats were sacrificed after taking blood samples. Left legs were preserved for histopathological and RT- PCR examinations. While, the right legs were kept for recording of isometric muscle contractility.
Results: Dex group showed marked decrease in muscle mass, isometric contraction forces, antioxidant enzymes and Mechano-Growth Factor (MGF) expression together with increase in myostatin expression and malondehyde. FA ad-ministration improved all these deleterious effects of Dex on both skeletal muscle fibers. This beneficial effect of FA was proved by histopathological improvement of sarcoplasmic degeneration, inflammatory cells infiltration and Zenker's necrosis of muscle bundle which featured rats' muscles of Dex group.
Conclusion: Ferulic acid, as an antioxidant and anti-inflammatory, can be used as an adjuvant therapy with anti-inflammatory corticosteroids to augment its therapeutic effect and reduce its myotrophic changes.