**5. Biomolecules of mushrooms in neurodegenerative diseases (NDs)**

Bioactive molecules in mushrooms also prevent the progression of different NDs. Motor symptoms linked with Parkinson's disease (PD) are significantly prevented by a diet rich in mushroom supplements. In addition, the clinical symptoms of PD were also alleviated by mushroom supplements rich in phytochemicals, minerals, and vitamins [79]. Anti-inflammatory and antioxidative activity is exhibited by dietary mushrooms containing significant quantities of carotenoids, polysaccharides, minerals, polyphenols, and vitamins [80]. The two major factors that are responsible for the progression of PD are oxidative stress and neuroinflammation. Thus, the biomolecules present in edible mushrooms offer significant neuroprotection by their antioxidative and anti-inflammatory activity by preventing the progressive degeneration of dopaminergic neurons [79]. One of the major factors responsible for the generation of neuroinflammation in PD is the activation of microglial cells. *Ganoderma lucidum* extract (GLE) inhibited the activation of these microglial cells and ultimately preventing the progressive degeneration of dopaminergic neurons in PD. Tumor necrosis factoralpha (TNF-a) and interleukin-1b (IL-1b) are the examples of some important proinflammatory cytokines whose expression was downregulated by GLE in a dose-dependent manner and can be treated by natural antibiotics reported in [81]. Further progression of PD is prevented by inhibition of these proinflammatory cytokines by GLE. Thus, the treatment of PD, GLE should be utilized as an effective anti-inflammatory medication [82]. For the treatment of PD, niacin-rich food can be very beneficial and offers significant protective activity. Niacin-rich mushroom content offers potential therapeutic efficacy in the treatment of PD [83]. In the rotenone intoxicated model of PD, neuroprotective activity was shown by the Agaricus blazei extract (ABE). ABE also improves rotenone-induced non-motor and motor complications in PD. Therefore, for the treatment of PD, ABE might also be utilized as a nutritional supplement [84]. Some herbal plants like *Tinospora cordifolia*, *Withania somnifera*, *Mucuna pruriens* (Mp), and the essential oils also exhibit neuroprotective activity similar to mushrooms in toxin-induced PD mouse models [85–87]. In addition, bioactive components of Mp like Ursolic acid also exhibits potent antioxidative and anti-inflammatory property in toxin-induced PD model [88–90]. Chlorogenic acid also exhibits a similar AntiParkinsonian activity in the mouse model of PD [91]. Similar to PD, in Alzheimer's disease (AD), nutritional mushroom provides important biomolecules that help to improve the quality of AD patients. Neuroinflammation along with oxidative stress mainly contributes to the pathogenesis of AD. The redox status in the cell of AD is significantly impaired [1]. Mushrooms have all the essential components that restore the normal balance of the redox system in AD models and patients. Proper and accurate functioning of mitochondria is required to maintain energy homeostasis. The synthesis of vital energy equivalents is hampered by abnormal mitochondrial functioning. In the neuroprotective network, inflammasome is an example of a very vital component. In AD, mitochondrial functioning was improved by Coriolus and Hericium. Normal redox balance was also maintained by these two nutritional mushrooms. Thus, energy homeostasis in AD was maintained by the above-mentioned two mushrooms by their antioxidative and anti-inflammatory properties [92]. One of the best examples of both medicinal and edible mushrooms is the *Hericium erinaceus* (HE). Both in vitro and in vivo model systems show the neuroprotective activity of HE. The aqueous extract of HE rich in a mycelium polysaccharide shows potent anti-apoptotic activity in l-glutamic acid (l-Glu) induced differentiated PC12 (DPC12) cell lines. The AD mouse model induces by
