Curcumin, the yellow colour in the spice turmeric, has a muscle strengthening effect, and this is most pronounced in muscles that are recovering. According to an animal study done at Emory University in 1999, curcumin can speed up muscle recovery by at least a factor five.
The protective effect of curcumin on muscles is not just a story dreamt up by a manufacturer of curcumin preparations. Yes, there is a sponsored study in which athletes recovered faster after training by taking a supplement containing curcumin. But US army researchers also stumbled across the muscle-recovery effects of curcumin. And a recent French study has confirmed the American findings.
In 1999 pharmacologists at Emory University published the results of a dramatic experiment in AJP – Cell Physiology, which is perhaps even more convincing than the more sophisticated experiments published later. In that study the researchers inflicted damage on the jaw and calf muscle tibialis of mice by exposing them to extreme cold. They immediately started giving the mice curcumin. They injected 0.15-0.2 ml fluid directly into the mice’s small intestine every day. The fluid contained a curcumin solution. A control group was injected with fluid containing no active ingredients after the muscle damage had been inflicted.
The researchers measured the recovery of the damaged tissues by examining the concentration of embryonic myosin heavy chain [EMHC], a marker for muscle recovery. The graph below shows the increase of EMHC for the two groups.
The photos below show the damaged jaw muscle tissue after 10 days. The upper photo shows tissue from a mouse that had been given 20 microgram curcumin/kg bodyweight; the lower photo is of tissue from a mouse in the control group. The bar indicates a length of 100 micrometre.
Mice treated with the optimal dose [20 microgram/kg/day] showed muscle recovery after 4 days that untreated mice only obtained after 20 days. So curcumin speeded up the muscle recovery by a factor five.
“Curcumin is the first example of a pharmacological agent with a potent effect on stimulating muscle regeneration after trauma”, the researchers conclude. “Enhanced repair of muscle would be beneficial not only in muscle trauma but also in reconstructive surgery and sports-related injuries.”
Systemic administration of the NF-kappaB inhibitor curcumin stimulates muscle regeneration after traumatic injury.
Skeletal muscle is often the site of tissue injury due to trauma, disease, developmental defects or surgery. Yet, to date, no effective treatment is available to stimulate the repair of skeletal muscle. We show that the kinetics and extent of muscle regeneration in vivo after trauma are greatly enhanced following systemic administration of curcumin, a pharmacological inhibitor of the transcription factor NF-kappaB. Biochemical and histological analyses indicate an effect of curcumin after only 4 days of daily intraperitoneal injection compared with controls that require >2 wk to restore normal tissue architecture. Curcumin can act directly on cultured muscle precursor cells to stimulate both cell proliferation and differentiation under appropriate conditions. Other pharmacological and genetic inhibitors of NF-kappaB also stimulate muscle differentiation in vitro. Inhibition of NF-kappaB-mediated transcription was confirmed using reporter gene assays. We conclude that NF-kappaB exerts a role in regulating myogenesis and that modulation of NF-kappaB activity within muscle tissue is beneficial for muscle repair. The striking effects of curcumin on myogenesis suggest therapeutic applications for treating muscle injuries.
PMID: 10444409 [PubMed – indexed for MEDLINE]