Unlocking the Secrets of Probiotics – A Therapeutic Breakthrough for Major Depressive Disorders

Abstract

The human gut has 12 distinct phyla, among which Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes make up ˃90%. Depressed individuals are a significant phylum and are differentiated from healthy individuals by their firmicutes. The microbiome is a key component of the pathological basis of major depressive illness as a result of disruption of the microbiota-gut-brain (MGB) axis. The fact is that there is bidirectional communication inside the brain, stomach, and brain-gut, wherein the brain highlights a systemic disease characterized by both brain and peripheral dysfunction. According to the microbiota hypothesis, MGB axis dysfunction is a significant contributor to the pathogenic underpinnings of major depressive disorder (MDD). The etiology of MDD is complicated and includes an imbalance of neurotransmitters, an impaired hypothalamic-pituitary-adrenal (HPA) axis, inflammation, and the MGB axis. According to research, having an aberrant microbiome or a disjointed MGB axis may directly cause psychiatric diseases such as MDD. Hence, resolving these issues may help with depression symptoms. Probiotics may therefore have therapeutic benefits for psychiatric symptoms by fostering healthy and balanced gut flora. The probiotic Bifidobacterium longum NCC3001 has been shown to reduce depression scores. In this review, the unknown mysteries and myths of probiotics are unlocked with special attention given to MDD or depression.