The molecular mechanisms of probiotic strains in improving ageing bone and muscle of <scp>d</scp> ‐galactose‐induced ageing rats
Yan-Yan Hor, Cheong Hwa Ooi, Lee-Ching Lew, Mohd Hafiidz Jaafar, Amy Sie-Yik Lau, B.‐K. Lee, Azali Azlan, Sy Bing Choi, Ghows Azzam, Min‐Tze Liong
Abstract
AIM: The aim of this study was to evaluate the molecular mechanisms of Lactobacillus strains in improving ageing of the musculoskeletal system. METHODS AND RESULTS: The anti-ageing mechanism of three probiotics strains Lactobacillus fermentum DR9, Lactobacillus paracasei OFS 0291 and L. helveticus OFS 1515 were evaluated on gastrocnemius muscle and tibia of d-galactose-induced ageing rats. Upon senescence induction, aged rats demonstrated reduced antioxidative genes CAT and SOD expression in both bone and muscle compared to the young rats (P < 0·05). Strain L. fermentum DR9 demonstrated improved expression of SOD in bone and muscle compared to the aged rats (P < 0·05). In the evaluation of myogenesis-related genes, L. paracasei OFS 0291 and L. fermentum DR9 increased the mRNA expression of IGF-1; L. helveticus OFS 1515 and L. fermentum DR9 reduced the expression of MyoD, in contrast to the aged controls (P < 0·05). Protective effects of L. fermentum DR9 on ageing muscle were believed to be contributed by increased AMPK-α2 expression. Among the osteoclastogenesis genes studied, TNF-α expression was highly elevated in tibia of aged rats, while all three probiotics strains ameliorated the expression. Lactobacillus fermentum DR9 also reduced the expression of IL-6 and TRAP in tibia when compared to the aged rats (P < 0·05). All probiotics treatment resulted in declined proinflammatory cytokines IL-1β in muscle and bone. CONCLUSIONS: Lactobacillus fermentum DR9 appeared to be the strongest strain in modulation of musculoskeletal health during ageing. SIGNIFICANCE AND IMPACT OF THE STUDY: The study demonstrated the protective effects of the bacteria on muscle and bone through antioxidative and anti-inflammatory actions. Therefore, L. fermentum DR9 may serve as a promising targeted anti-ageing therapy.