A chronic low dosage of taurine induces muscle weakness in castrated-aged mice

Taurine is an abundant metabolite associated with regulation of cell volume. Several signaling pathways are stimulated at a micromolar concentrations of taurine. However, most of the experimental studies employ this compound at a very high concentration (tens of millimolar). In this study, the role of a chronic treatment with a micromolar dosage of taurine in the physical performance of skeletal muscle of castrated-aged mice was characterized. Taurine was administered in drinking water (800 μM) to 9-months-old castrated (or sham) mice at approximately 20 mg/kg per day for 12 weeks. The weight of the mice, grip strength, food and water intake were monitored. Soleus or EDL muscles were dissected for determinations of force and fatigue. Castrated mice show a slow increase in body mass and a sustained reduction of grip strength. The taurine treatment delays the weigh recovery and generates a decrease in force of castrated and sham mice. No effect of taurine was observed in young mice. The food intake was significantly reduced in castrated mice treated with taurine (with no effect in water intake). The raw force generation or muscle mass in EDL and soleus muscle were similar in treated mice in comparison with control groups. Interestingly, the taurine treatment generated an increased fatigability in both EDL and soleus muscle. We suggest that a submillimolar concentration of taurine, chronically administered during aging, produce negative effect in physical performance. Caution should be taken when this compound is routinely consumed by old adults.