Exercise: a non-drug strategy of NK cell activation

Abstract

Natural killer (NK) cells are a critical component of the innate immune system and one of the immune cells most sensitive to exercise. So far, it is widely believed that moderate exercise can significantly enhance the proliferation and activity of NK cells, strengthening immune function. However, the impact of exercise on NK cells is a dynamic and complex process. In addition to the type of exercise, the frequency, intensity, and duration of exercise are also key factors. This article not only briefly summarizes the activation mechanisms of NK cells but also delves into the potential importance of exercise as a non-pharmacological strategy in modulating NK cell activity and enhancing the immune system. Emerging studies have indicated that the timing and regularity of exercise bouts might also influence NK cell responses. Moreover, the interaction between exercise and other components of the immune system, such as cytokines and chemokines, could further modulate the functionality of NK cells. The above research is of crucial significance for achieving a deeper understanding of the intricate connection between exercise and NK cell function, as well as the development of effective health promotion strategies. In addition, further research is needed to investigate the effects of long-term exercise on NK cell function and the interaction between exercise and NK cell-mediated immune responses. Translating these research findings into precisely tailored exercise programs for specific populations, taking into account factors like age, health status, and genetic predisposition, could potentially offer unprecedented prospects for further advancements in this burgeoning field of study.

Figure 1. Exercise can promote the release of various cytokines and inflammatory factors such as interleukin (IL)-6, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, and IL-1β. In addition, exercise can also promote the release of neurotransmitters such as adrenaline and noradrenaline. Adrenaline and noradrenaline bind to adrenergic receptors and β2-adrenergic receptors. After receptor activation, the signal is transmitted through intracellular signaling pathways such as PI3K-Akt, ERK, JNK, p38 MAPK, and JAK-STAT into the interior of natural killer (NK) cells. The activating receptors on the surface of NK cells include NKG2D and DNAM-1, among others. When these receptors bind to their ligands, NK cells are activated, initiating signal transduction pathways. NK cells contain abundant perforin and granzymes, which can eliminate tumor cells.