Plain language summary
Constipation is a common complaint among people with depression and may negatively affect their quality of life. In association with this, previous studies have shown a correlation between the reduction of Lactobacillus or Bifidobacterium strains in the gut of patients with major depressive disorder. Thus, this two-arm, parallel-design, randomised, double-blinded, placebo-controlled trial examined the effects of supplementing fermented milk with Lacticaseibacillus paracasei Strain Shirota or LcS (previously known as Lactobacillus casei strain Shirota) on constipation in people with depression. Symptoms of constipation, stool problems, and depressive symptoms improved after 9 weeks of consuming fermented milk containing LcS. The abundance of Adlercreutzia, Megasphaera, and Veillonella increased significantly in the intervention group. In contrast, the abundance of bacteria related to mental disorders such as Rikenellaceae_RC9_gut_group, Sutterella and Oscillibacter significantly decreased after the intervention. After 9 weeks of intervention with LcS, a significant reduction in serum proinflammatory cytokines such as IL-1β, IL-6, and TNF-α was observed in patients with depression. The intervention group also showed a decrease in inflammation-causing bacteria, Surrerella, which correlated with a reduction in proinflammatory cytokines. The mechanisms driving the changes in gut microbial composition, depression, and gastrointestinal symptoms after LcS intervention need to be evaluated in more robust studies. Healthcare professionals can use the results of the study to better understand how probiotics can reduce constipation and depression and improve gut microbial composition.
Abstract
Probiotics have been shown to benefit patients with constipation and depression, but whether they specifically alleviate constipation in patients with depression remains unclear. The aim of this study was to investigate the effect of Lacticaseibacillus paracasei strain Shirota (LcS), formerly Lactobacillus casei strain Shirota, on constipation in patients with depression with specific etiology and gut microbiota and on depressive regimens. Eighty-two patients with constipation were recruited. The subjects consumed 100 mL of a LcS beverage (108 CFU/mL) or placebo every day for 9 weeks. After ingesting beverages for this period, we observed no significant differences in the total patient constipation-symptom (PAC-SYM) scores in the LcS group when compared with the placebo group. However, symptoms/scores in item 7 (rectal tearing or bleeding after a bowel movement) and items 8-12 (stool symptom subscale) were more alleviated in the LcS group than in the placebo group. The Beck Depression Index (BDI) and Hamilton Depression Rating Scale (HAMD) scores were all significantly decreased, and the degree of depression was significantly improved in both the placebo and LcS groups (p < 0.05), but there was no significant difference between the groups. The LcS intervention increased the beneficial Adlercreutzia, Megasphaera and Veillonella levels and decreased the bacterial levels related to mental illness, such as Rikenellaceae_RC9_gut_group, Sutterella and Oscillibacter. Additionally, the interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α) levels were significantly decreased in both the placebo and LcS groups (p < 0.05). In particular, the IL-6 levels were significantly lower in the LcS group than the placebo group after the ingestion period (p < 0.05). In conclusion, the daily consumption of LcS for 9 weeks appeared to relieve constipation and improve the potentially depressive symptoms in patients with depression and significantly decrease the IL-6 levels. In addition, the LcS supplementation also appeared to regulate the intestinal microbiota related to mental illness.
Methodological quality
Jadad score
:
4
Allocation concealment
:
No
