The Serum Brain-Derived Neurotrophic Factor Increases in Serotonin Reuptake Inhibitor Responders Patients with First-Episode, Drug-Naïve Major Depression

From Stress to Synapse: The Neuronal Atrophy Pathway to Mood Dysregulation

Mood disorders, including major depressive disorder and bipolar disorder, are among the most prevalent mental health conditions globally, yet their underlying mechanisms remain incompletely understood. This review critically examines the neuronal atrophy hypothesis, which posits that chronic stress and associated neurobiological changes lead to structural and functional deficits in critical brain regions, contributing to mood disorder pathogenesis. Key mechanisms explored include dysregulation of neurotrophic factors such as brain-derived neurotrophic factor (BDNF), elevated glucocorticoids from stress responses, neuroinflammation mediated by cytokines, and mitochondrial dysfunction disrupting neuronal energy metabolism. These processes collectively impair synaptic plasticity, exacerbate structural atrophy, and perpetuate mood dysregulation. Emerging evidence from neuroimaging, genetic, and epigenetic studies underscores the complexity of these interactions and highlights the role of environmental factors such as early-life stress and urbanization. Furthermore, therapeutic strategies targeting neuroplasticity, including novel pharmacological agents, lifestyle interventions, and anti-inflammatory treatments, are discussed as promising avenues for improving patient outcomes. Advancing our understanding of the neuronal atrophy hypothesis could lead to more effective, sustainable interventions for managing mood disorders and mitigating their global health burden.

The link between BDNF and platelets in neurological disorders

Platelets are considered one of the most important reservoirs not only of growth factors, but also of neurotrophic factors that could contribute to the repair of vascular lesions and the prevention of neurological deterioration. Among these factors, Brain-Derived Neurotrophic Factor (BDNF) - a protein belonging to the neurotrophin family - is widely expressed both in the hippocampus and in platelets. Platelets constitute an important reservoir of BDNF; however, little is known about the factors modulating its release into the circulation and whether anti-platelet drugs affect this secretion. In this review, we have discussed the link between BDNF and platelets and their role in neurological disorders.

Are BDNF and Stress Levels Related to Antidepressant Response?

Antidepressant response is a multifactorial process related to biological and environmental factors, where brain-derived neurotrophic factor (BDNF) may play an important role in modulating depressive and anxious symptoms. We aimed to analyze how BDNF impacts antidepressant response, considering the levels of anxiety.

METHODS

A total of 40 depressed adults were included. We evaluated initial serum BDNF, anxiety through the State-Trait Anxiety Inventory (STAI), and the severity of depressive symptoms by the Hamilton Depression Rating Scale (HDRS). Participants received antidepressant treatment for 8 weeks, and response to treatment was evaluated according to the final HDRS scores.

RESULTS

Basal BDNF was higher in responders compared to non-responder depressed patients, in addition to being inversely associated with the severity of anxiety and depression.

CONCLUSIONS

Baseline BDNF serum is an adequate predictive factor for response to antidepressant treatment with SSRI, with lower pre-treatment levels of BDNF associated with higher anxiety symptoms after treatment. Stress levels could influence the response to treatment, but its association was not conclusive.

A Decade of Dedication: Pioneering Perspectives on Neurological Diseases and Mental Illnesses

Welcome to Biomedicines' 10th Anniversary Special Issue, a journey through the human mind's labyrinth and complex neurological pathways [...].

Neural Correlates and Molecular Mechanisms of Memory and Learning

Memory and learning are essential cognitive processes that enable us to obtain, retain, and recall information [...].

Emerging Translational Research in Neurological and Psychiatric Diseases: From In Vitro to In Vivo Models

Revealing the underlying pathomechanisms of neurological and psychiatric disorders, searching for new biomarkers, and developing novel therapeutics all require translational research [...].

Evaluation of Antidepressive-like Behaviours and Oxidative Stress Parameters in Mice Receiving Imipramine-Zinc Complex Compound

The study aimed to evaluate the antidepressant-like effects of an imipramine-zinc (IMI-Zn) complex compound on mice and assess the level of oxidative stress parameters. The research also investigated whether the IMI-Zn complex showed superior antidepressant activity compared to individual treatments of both compounds at effective doses and their joint administration at subtherapeutic doses. The study was conducted on mice. Forced swim (FST), tail suspension (TST), and locomotor activity tests were used for behavioral studies. The results demonstrated the IMI-Zn complex's dose-dependent antidepressant potential when orally administered to mice. Its efficacy was similar to the separate administration of therapeutic doses of imipramine (IMI) and zinc (Zn) and their joint administration at subtherapeutic doses. Moreover, subjecting mice to acute stress did not significantly affect the activity of on glutathione peroxidase (GPX), glutathione reductase (GR), and total antioxidant status (TAS), possibly due to the short exposure time to the stress stimulus. By developing the IMI-Zn complex, it might be possible to simplify the treatment approach, potentially improving patient compliance by combining the therapeutic effects of both IMI and Zn within a single compound, thus addressing one of the contributing factors to non-compliance in depression therapy. The IMI-Zn complex could be a valuable strategy to optimize therapeutic outcomes and balance efficacy and tolerability.