Table 2.

Summary of the antifatigue functions and possible mechanisms of mushrooms.

Antifatigue functions of mushrooms	Detailed mechanisms
Muscular function improvement	(i) Inhibits production and accelerate clearance of lactic acid; (ii) Increases glycogen storage in liver and muscle; (iii) Reduces blood urea nitrogen from protein breakdown; (iv) Increases lactate dehydrogenase activity; (v) Promotes the expression of skeletal muscle key metabolic regulators of AMPK, PGC-1α, and PPAR-δ; (vi) Stimulates the expression of lactate monocarboxylate transporter and glucose transporter.
Antioxidant function	(i) Scavenges DPPH, hydroxyl radical, superoxide anion radical, and nitric oxide; (ii) Inhibits lipid peroxidation; (iii) Stimulates antioxidant enzymes of SOD, GSH-Px, catalase, and glutathione reductase.
Cardiovascular function improvement	(i) Vasodilation in areas that need blood supply increase.
Immunomodulation enhancement	(i) Activates macrophages to engulf foreign invaders; (ii) Increases T helper cells to control and regulate other immune cells; (iii) Increases T helper: T suppressor cells to enhance immune system activity; (iv) Increases natural kill cells activity to identify and remove foreign invaders; (v) Improves cytokines expression to regulate cellular communication and immune response in infective sites.
Hormone regulation improvement	(i) Balances testosterone level to improve muscle development.
Hepatic function improvement	(i) Increases energy state by increasing ATP to Pi ratio; (ii) Increases liver blood flow; (iii) Promotes liver protein and RNA synthesis.
Blood glucose regulation improvement	(i) Increases circulating insulin to reduce glucose back to normal; (ii) Increases relevant enzyme activities including glucokinase, hexokinase, and glucose-6-phosphate dehydrogenase to increase glucose metabolic rate.