Szu-Hsien Yu

Can mesenchymal stem cell lysate reverse aging

Recent findings regarding uses of adipose-derived mesenchymal stem cell (MSC)-lysate on weight loss and improved glucose tolerance in mice on a high-fat diet suggest an encouraging possibility of using MSC lysate for an anti-aging intervention in humans. However, weight loss and lipopenia during late life can be as life-threatening as hyperglycemia during early adulthood. For this 3-year lifelong experiment, a total of 92 rats were randomized into the vehicle-injected group (F=22; M=24) and the MSC lysate injected group (F=22, M=24). We examined longevity, spontaneous locomotor activity, and body composition in rats maintained on a normal diet and received an intermittent treatment of human adipose-derived MSC lysate (3 times a week, 11 times a month given every second month), starting at 12 months of age until natural death. In substantiating previous knowledge regarding the effects of long-term MSC lysate treatments on fat loss and insulin resistance, the present findings also highlighted a shortened average lifespan, a longer inactive time, and a greater bone loss with a relative increase of lean mass in MSC lysate rats with respect to controls. Conclusion: Our data suggest that MSC lysate treatments stimulate disparity in tissue development and produce a cachexia-like effect to decrease longevity.

Hemodynamic Changes in the Dominant and Non-Dominant Arms after a Tennis Training Session

Tennis players develop asymmetric dimension of dominant or non-dominant arms. Since nutrients and trophic factors (such as insulin) are delivered through blood, we hypothesized that tennis training causes asymmetric blood distribution to arms is associated with this structural difference. In this study, nine young volunteers (age 19.8±0.5 years) were recruited for a session of high-frequency forehand tennis training (20 balls/min) for 10 min. Muscle blood distribution of the non-dominant and dominant arms was then determined by tissue hemoglobin (TH) concentrations using near-infrared spectroscopy (NIRS) during 2-day recovery period. The circumference of the arms of their racket hands (dominant arms) was greater than that of the opposite arms. Forearm oxygen saturation was significantly lower in both arms immediately after training, whereas, the dominant arms oxygen saturation was significantly higher than that of the non-dominant arm one day after exercise. Oxygenated hemoglobin of the non-dominant arm was significantly lower immediately and also one day after exercise. Comparably, the dominant arm has higher oxygenated hemoglobin level than the non-dominant arm one day after training. In addition, the deoxygenated hemoglobin value of the dominant arm was significantly higher immediately after exercise. Before training, no difference in TH was found between arms. However, dominant arm showed higher TH concentrations than the nondominant arm immediately after training and continued to day-1. TH concentration of the non-dominant arm was significantly lower one day-1 after tennis training compared to baseline. These results of the study provide a potential basis that might explain the asymmetric development of arm size in professional tennis players.