Neurobiology of suicidal behavior

Suicide is a serious public health problem and a multifactorial phenomenon resulting from intentional self-destructive behavior influenced by genetic, social, economic, and psychological vulnerabilities. The objective is to identify and synthesize the main macro and microscopic neurobiological changes associated with suicidal behavior, considering molecular, genetic, neurological, and neurochemical aspects. To this end, an integrative review of the literature was conducted in the PubMed Central, Scopus, Web of Science, and PsycINFO databases, using the MeSH terms “Neurobiology” and “Suicidal Behavior” and complementary keywords. After applying the inclusion and exclusion criteria, 20 studies published in the last five years were analyzed. Thus, it is observed that specific genes expressed in the brain and pituitary gland, as well as variations associated with depression and anxiety, increase vulnerability to suicide, involving the hypothalamic-pituitary-adrenal axis and neuroinflammatory processes. Evidence also points to dysfunctions in specific brain structures and interaction with environmental stressors, in addition to the potential of biomarkers, such as telomere length, mitochondrial function, and mRNA expression, in predicting risk and guiding interventions. It is concluded that an integrated understanding of these factors can improve clinical assessment, support personalized prevention strategies, and contribute to the development of therapeutic approaches.