“…Brain-derived neurotrophic factor (BDNF) is a neurotrophin that regulates neurogenesis, neuronal maturation, and synap- tic plasticity. 33 It is a vital regulator of the neuroimmune axis and an essential indicator for evaluating neural plasticity. 34,35 Several studies have shown that depression is associated with the loss and damage of neurons in several brain regions, such as the hippocampus and cerebral cortex, and the latter is also related to the changes in the levels of neurotrophic factors (such as BDNF) in specific brain regions.…”