Pharmacology of natural bioactive compounds used for management of Huntington diseases: An overview

Huntington's disease (HtD), an inherited genetic neurodegenerative disorder, posed threat to elderly population world-wide. HtD is caused by the repetition of cytosine-adenine-guanine (CAG) in HtD gene, which further leads to the formation of a mutant Huntington (mHtt) protein that is responsible for neuronal dysfunction and cell death. Symptoms of HtD usually begin in adulthood and progress slowly, resulting in psychiatric disturbances, motor deficits and cognitive dysfunction. The medium spiny neurons of the striatum and cortex are mainly affected in HtD. Multiple hypotheses have been proposed to elucidate the underlying mechanisms that lead to neuronal dysfunction and cell death. This typically includes molecular genetics, oxidative stress (OS), excitotoxicity, mitochondrial impairment etc. Natural bioactives are a diverse group of compounds derived from plants, animals and microorganisms. They have been found to modulate multiple signaling pathways involved in the development of HtD and have potentials in reducing OS, neuroinflammation, and neuronal death, which are key pathological processes in HtD.Mostly natural bioactive offers protection either by down-regulating the OS, excitotoxicity, mitochondrial dysfunctions, microglial inactivation, neuroinflammation and/or by upregulating ubiquitin-proteasome system, autophagy & lysosomal degradation pathway, apoptotic pathway, purinergic signaling pathway.In this chapter, we have summarized various natural bioactives that exhibit therapeutic potential against HtD. Furthermore, we have discussed the opportunities and challenges associated with the development of safe and effective natural bioactives-based therapies against HtD.