Besides, sarcopenia reduces the level of regulating myokines that play a crucial role in the muscle-brain cross-talk [61], including interleukin 6 (IL-6) [62], insulin-like growth factor1 (IGF-1) [63], etc. In vitro studies showed that IL-6 serves as an important regulator of neuron function in health and disease [64]. The gene discussed is IGF1; the disease is sarcopenia.