Effects of non-euphoric plant cannabinoids on muscle quality and performance of dystrophic mdx mice.

BACKGROUND AND PURPOSE: Duchenne muscular dystrophy (DMD), caused by dystrophin deficiency, results in chronic inflammation and irreversible skeletal muscle degeneration. Moreover, the associated impairment of autophagy leads to the accumulation of damaged intracellular organelles that greatly contribute to the aggravation of muscle damage. We explored the possibility of using non-euphoric compounds present in Cannabis sativa, including cannabidiol (CBD), cannabidivarin (CBDV) and tetrahydrocannabidivarin (THCV) to reduce inflammation, restore functional autophagy and positively enhance muscle function in vivo.

KEY RESULTS: We found that CBD and CBDV promote the differentiation of murine C2C12 myoblast cells into myotubes by increasing [Ca2+ ]i mostly via TRPV1 activation, an effect that undergoes rapid desensitization. CBD and CBDV also promoted the differentiation of myoblasts from DMD donors. In primary cultures prepared from satellite cells isolated from healthy donors, not only CBD and CBDV but also THCV promoted myotube formation, in this case mostly via TRPA1 activation. In mdx mice, CBD (60 mg Kg-1 ), CBDV (60 mg Kg-1 ) prevented the loss of locomotor activity at two distinct ages (from 5 to 7 and 32 to 34 weeks of age). This effect was associated with a reduction in tissue and plasma pro-inflammatory markers, together with the restoration of autophagy.

CONCLUSION AND IMPLICATIONS: We provide new insights into plant cannabinoid interactions with TRP channels in skeletal muscle, highlighting a potential opportunity for novel co-adjuvant therapies to prevent muscle degeneration in DMD patients.