Table 1.

Classification of TRP channels.

TRP Channels		Function	Distribution in Brain regions	Disorders	References
TRPV Subfamily	TRPV1	Enhance neuronal death by agonist, such as Capsaicin, pain and noxious thermal sensing	Hippocampus, cortex, cerebellum, olfactory bulb, amygdala, mesencephalon and hindbrain	AD, PD	[101]
	TRPV4	Stimulates and upregulates neuronal inflammatory responses Prevent release of pro-inflammatory cytokine, thermal sensing	Hippocampus, cortex, cerebellum and thalamus	AD	[102]
TRPM Subfamily	TRPM2	Activate due to ROS, apoptotic cell death, Ca2+ entry in pancreatic beta cells, temperature dependent,	Hippocampus, cortical neurons, substantia nigra and striatum	ALS, PD, AD,	[103]
	TRPM7	Aggravate cell damage by increase Ca2+ induced oxidative stress, cell cycle regulation, Mg2+ homeostasis, entry to trace metals, promote cell growth and survival	Mouse cortical neurons Hippocampus, cerebrum, cerebellum and truncus encephali	ALS, AD,	[104,105]
TRPC Subfamily	TRPC1	Attenuates neurotoxicity and unfolded protein response, Regulate SOCE and amplifies survival of dopaminergic neuron, coupling to glutamate receptors, facilitate slow excitatory postsynaptic currents	Hippocampus, amygdala, cerebellum, substantia nigra and inferior colliculus	ALS, PD,	[106]
	TRPC3	Arbitrate neuronal differentiation, vasomotor function, inhibit to release cytokines and NO	Widely distributed in rat CNS Human dopaminergic neurons Globus pallidus striatum, Cerebellum	AD, ALS, PD	[107]
	TRPC4	Activate growth of neurite length, vasomotor function, microvascular permeability	Mouse hippocampal pyramidal neurons Frontal cortex, lateral septum, and ventral subiculum, Amygdala	Anxiety, Depression	[80]
	TRPC5	Reduce elevation of SOCE, brain development, growth cone morphology and guidance,	Hippocampus, Frontal cortex, Cerebellum, substantia nigra, Amygdala, Striatum, hypothalamus	ALS, PD	[106]
	TRPA1	Activation and progression of astrocytes, facilitates Ca2+ entry, promote activation of proinflammatory cytokines	Hippocampus, Brain stem, cerebral cortex	AD, Migraine	[108,109]
TRPP Subfamily	TRPP1	Acts as mechanoreceptor, sensing external stress, triggering cascade of signaling pathways	Endothelial cells lining BBB, ER membranes	Psoriasis, Muscular dystrophy, AD, PD, Renal hypoplasia	[110]
	TRPP2
	TRPP3		Hippocampus, Cerebellum, olfactory bulb, thalamus, midbrain