Effect of Lacticaseibacillus paracasei Strain Shirota on Improvement in Depressive Symptoms, and Its Association with Abundance of Actinobacteria in Gut Microbiota

Abstract

We previously reported lower counts of lactobacilli and Bifidobacterium in the gut microbiota of patients with major depressive disorder (MDD), compared with healthy controls. This prompted us to investigate the possible efficacy of a probiotic strain, Lacticaseibacillus paracasei strain Shirota (LcS; basonym, Lactobacillus casei strain Shirota; daily intake of 8.0 × 1010 colony-forming units), in alleviating depressive symptoms. A single-arm trial was conducted on 18 eligible patients with MDD or bipolar disorder (BD) (14 females and 4 males; 15 MDD and 3 BD), assessing changes in psychiatric symptoms, the gut microbiota, and biological markers for intestinal permeability and inflammation, over a 12-week intervention period. Depression severity, evaluated by the Hamilton Depression Rating Scale, was significantly alleviated after LcS treatment. The intervention-associated reduction of depressive symptoms was associated with the gut microbiota, and more pronounced when Bifidobacterium and the Atopobium clusters of the Actinobacteria phylum were maintained at higher counts. No significant changes were observed in the intestinal permeability or inflammation markers. Although it was difficult to estimate the extent of the effect of LcS treatment alone, the results indicated that it was beneficial to alleviate depressive symptoms, partly through its association with abundance of Actinobacteria in the gut microbiota.

How Microbes Affect Depression: Underlying Mechanisms via the Gut–Brain Axis and the Modulating Role of Probiotics

“…In a subgroup with a high depressive index at baseline, intervention subjects showed a significant improvement in depressive mood compared with subjects who received a placebo control. These results were supported by those from an open trial using the same probiotic strain in patients with MDD or bipolar disorder [130]. There, it was demonstrated that depressive symptoms and sleep quality were improved after LcS treatment, and the effect was associated with the gut microbiota composition, namely, abundance of Actinobacteria, including Bifidobacterium.…”

Characterization of Bacterial Microbiota of P.D.O. Feta Cheese by 16S Metagenomic Analysis

“…L. paracasei can be commonly found as the dominant nonstarter lactic acid bacterium in many ripened cheeses, and select strains of this species may be added to cheese milk as adjuncts for outcompeting undesired microorganisms and improving cheese quality by contributing to cheese flavor diversification and intensification [36]. Moreover, the probiotic properties of L. paracasei have been investigated in recent studies [37]. Other facultative heterofermentative NSLAB detected in very low populations were Lacticaseibacillus casei (former Lactobacillus casei), Latilactobacillus graminis (former Lactobacillus graminis), Latilactobacillus sakei (former Lactobacillus sakei) and Lacticaseibacillus zeae (former Lactobacillus zeae).…”

The Role of Psychobiotics in Supporting the Treatment of Disturbances in the Functioning of the Nervous System—A Systematic Review

“…The knowledge of the gut microbiota composition prior to and after the probiotic supplementation provides important information about the gut microbiome and its influence on depressive disorders. Otaka et al [ 87 ] used Lacticaseibacillus paracasei strain Shirota. The researchers found the link between the reduction in depressive symptoms and the gut microbiome.…”

“…The researchers found the link between the reduction in depressive symptoms and the gut microbiome. Reduced symptoms of depression were partially related to the increase in Actinobacteria in the gut microbiome [ 87 ]. Most of the studies illustrated by us showed a positive effect on depressive behavior among patients.…”