Abstract : In vitro pharmacological studies play a crucial role in elucidating the molecular and cellular mechanisms underlying the effects of antidepressants on the central nervous system (CNS). These studies employ cellular models, brain tissue samples, and isolated molecular systems to examine drug interactions with key neurotransmitter systems. Critical areas of research include receptor binding assays for serotonin, norepinephrine, and dopamine receptors, as well as inhibition of neurotransmitter reuptake, primarily through serotonin and norepinephrine transporters. Additionally, antidepressants influence enzyme activity, particularly through monoamine oxidase inhibition, and modulate ion channels, such as voltage-gated sodium and potassium channels, affecting neuronal excitability. Further investigations explore the role of antidepressants in promoting neuroplasticity through neurotrophic factors like brain-derived neurotrophic factor (BDNF), which is associated with synaptic remodelling and resilience against stress-induced neuronal damage. Antidepressants also impact intracellular signalling pathways, including the cAMP/PKA, MAPK/ERK, and mTOR pathways, contributing to their therapeutic efficacy. Moreover, in vitro studies facilitate the assessment of oxidative stress modulation and the regulation of stress-related pathways implicated in depression. These insights not only enhance our understanding of antidepressant pharmacology but also pave the way for identifying novel therapeutic targets, ultimately advancing the development of more effective treatments for depression and other mood disorders.

Keyword : Antidepressants, Neurotransmitter transporters, Brain-derived neurotrophic factor (BDNF), Cell signalling pathways, Neuroplasticity.

Abstract : ABSTRACT Epigenetics plays a crucial role in gene regulation, and its implications in cancer therapy have led to the development of innovative epigenetic drugs. This review explores the fundamental principles of epigenetic modifications and highlights recent advancements in epigenetic pharmacology for cancer treatment and prevention. Current FDA-approved epigenetic therapies primarily include inhibitors targeting DNA methyl transferases (DNMTs) and histone deacetylases (HDACs). However, future therapeutic strategies may involve inhibitors of histone methyltransferases, histone demethylases, and other key epigenetic regulators. Epigenetic drugs exert their effects in two interconnected ways. Firstly, they restore aberrant epigenetic modifications in malignant and premalignant cells, thereby reversing dysregulated gene expression and serving as a foundation for epigenetic therapy. Secondly, these drugs modulate non-histone proteins that regulate crucial cellular processes such as proliferation, migration, and apoptosis. Through these mechanisms, epigenetic drugs induce cancer cell cycle arrest, differentiation, inhibition of tumour angiogenesis, and cell death via apoptosis, autophagy, necrosis, or mitotic catastrophe. This review provides an in-depth analysis of the molecular mechanisms underlying epigenetic drug action and their clinical applications. With ongoing research, novel epigenetic therapies hold promise for more precise and effective cancer treatments, paving the way for personalized medicine in oncology.

Keyword : Epigenetics, DNA methylation, histone acetylation, gene regulation, cancer therapy, epigenetic inhibitors, targeted therapy.