Vitamin D and N-Acetyl Cysteine Supplementation in Treatment-Resistant Depressive Disorder Patients: A General Review.

Major Depressive Disorder (MDD) is often a lifetime disabling mental illness as individuals with MDD might not benefit from standard-therapy, including both pharmacological and psychosocial interventions. Novel therapies are, therefore, required. It was shown by recent preclinical and clinical studies that the dysfunction of glutamatergic neurotransmission might be involved in the pathophysiology of MDD. Furthermore, neuroimmune alterations could have a significant role in the pathogenesis of MDD. Vitamin D is a neurosteroid hormone essential for several metabolic processes, immune responses, and for regulating neurotrophic-neuroprotective processes, neurotransmission and synaptic plasticity. Recent studies have also shown Vitamin D deficiency in patients with severe psychiatric disorders, including MDD. Lately, clinical studies have shown the neuroprotective action of N-acetyl cysteine (NAC) through the modulation of inflammatory pathways and via the modulation of synaptic release of glutamate in cortico-subcortical brain regions; the cysteine-glutamate antiporter. This paper reviews the therapeutic use of Vitamin D and NAC and among individuals with refractory MDD to the first- line pharmacological interventions, reviewing the clinical studies published in the last decade. A detailed summary of the current evidence in this area aims to better inform psychiatrists and general practitioners on the potential benefits of Vitamin D and NAC supplementation for this disorder. Nutraceutical supplementation with Vitamin D and NAC in treatment-resistant MDD patients may be important not only for improving depressive clinical manifestations but also for their safety and tolerability profile. This is of great interest, especially considering the need for treating special populations affected by MDD, such as youngsters and elders. Finally, the nutraceutical approach represents a good choice, considering its better compliance by the patients compared to traditional psychopharmacological treatment.

N-Acetyl Cysteine and Vitamin D Supplementation in Treatment Resistant Obsessive-compulsive Disorder Patients: A General Review.

OBJECTIVE: Obsessive-compulsive Disorder (OCD) is a disabling mental illness for which pharmacological and psychosocial interventions are all too often inadequate. This demonstrates the need for more targeted therapeutics. Recent preclinical and clinical studies have implicated the dysfunction of glutamatergic neurotransmission in the pathophysiology of OCD. Moreover, there are studies suggesting that neuroimmune abnormalities may play an important role in the pathogenesis of OCD. N-acetyl cysteine (NAC) is a safe and readily available agent that would modify the synaptic release of glutamate in subcortical brain regions via modulation of the cysteine-glutamate antiporter. The modulation of inflammatory pathways may also play a role in the benefits seen following NAC treatment. Therefore NAC can be considered a neuroprotective agent. METHODS: This paper explores the role of NAC in the treatment of OCD conditions refractory to first-line pharmacological interventions, reviewing the clinical studies published in the last decade. RESULTS: The possible benefit mechanisms of NAC for this disorder will be discussed, as well as the role of vitamin D supplementation, given its specific property of stimulating the formation of glutathione in the brain. CONCLUSION: Nutraceutical supplementation in treatment resistance OCD may be important not only for improving obsessive-compulsive symptomatology, but also from a psychological perspective, given its better acceptance by the patients compared to pharmacological treatment.