The modulatory effects of Lonicera caerulea L. extract and omega-۳ on sarcopenia via regulating PI۳K and FOXO signaling pathways in rats

Introduction: Sarcopenia is an inflammatory disease caused by a disruption of muscle homeostasis. Lonicera caerulea L. (Haskap berry) (HB) extract and omega-۳ (ω−۳) possess antioxidant and anti-inflammatory activities. This study assesses the potential ameliorating effects of HB extract and ω−۳ supplementation on dexamethasone (DEXA)-induced sarcopenia. Methods: Rats were divided into five groups; the negative control group was injected with saline (i.p.); groups ۲, ۳, ۴, and ۵ were injected with DEXA (۲ mg/kg/d, i.p.); groups ۳ and ۴ also received ۴۰۰ mg/kg/d and ۱۰۰ mg/kg/d of HB extract and ω−۳, respectively, while group ۵ received both treatments daily for ۲۱ days. The ameliorative effects of treatments were investigated by measuring lysosomal proteolytic enzyme cathepsin activity, phosphatidylinositol ۳ kinase (PI۳K) activity, nuclear factor kappa beta (NF-κB) level, and heme oxygenase-۱ (HO-۱) activity. The gene expression levels of muscle ring-finger protein (MuRF) and forkhead box O (FOXO) transcription factor were also evaluated. Biochemical and histological examinations were done on muscle tissues. Results: DEXA caused a significant elevation (P<۰.۰۵) in NF-κβ level and cathepsin activity in muscle tissue. Also, it significantly upregulated the muscle atrophy markers. Meanwhile, PI۳K and HO-۱ activities were significantly reduced. HB extract and ω−۳ administration significantly (P≤۰.۰۵) reversed these effects and downregulated the mRNA expression levels of MuRF and FOXO. Also, the histopathological examination confirmed these results. Conclusion: The current study proved the ameliorative effects of HB extract and ω−۳ on sarcopenia parameters. Therefore, they might be potential therapeutic agents for myopathy/sarcopenia.