A domestic strain of Lactobacillus rhamnosus attenuates cognitive deficit and pro-inflammatory cytokine expression in an animal model of Alzheimer’s disease

• Published in: Behavioural brain research 2025-01, Vol.476, p.115277, Article 115277
• Main Authors: Heydari, Ruhollah, Khosravifar, Mina, Abiri, Shervin, Dashtbin, Shirin, Alvandi, Amirhoushang, Nedaei, Seyed Ershad, Salimi, Zahra, Zarei, Fatemeh, Abiri, Ramin
• Format: Article
• Language: English
• Subjects: Alzheimer Disease - metabolism; Alzheimer’s disease; Animals; Cognitive Dysfunction - etiology; Cognitive Dysfunction - metabolism; cytokines; Cytokines - metabolism; Disease Models, Animal; Galactose - metabolism; Gastrointestinal Microbiome - physiology; Inflammation - metabolism; Lacticaseibacillus rhamnosus; Lactobacillus rhamnosus; learning; Male; Maze Learning - physiology; memory; probiotic; Probiotics - administration & dosage; Probiotics - pharmacology; Rats; Rats, Wistar; Spatial Memory - physiology
• ISSN: 0166-4328; 1872-7549; 1872-7549
• DOI: 10.1016/j.bbr.2024.115277

Microbiome dysbiosis plays a significant role in neuroinflammation and Alzheimer’s disease (AD). Therefore, gut microbiome restoration using appropriate probiotics may be beneficial in alleviating AD features. In this study, we investigated the effects of a domestic strain of Lactobacillus rhamnosus (L. rhamnosus) on spatial memory, and cytokines expression in an inflammation-based AD model. Male Wistar rats were randomly divided into four groups (six animals per group) of control, L. rhamnosus-only, D-galactose (D-gal)-only, and D-gal + L. rhamnosus. Spatial learning and memory were assessed using the Morris water maze test. IL-1β, IL-6, and TNF-α expression levels were measured using Real-Time qPCR. A significance level of 0.05 was used for statistical analysis. In contrast to the D-gal + L. rhamnosus-treated group, D-gal only treated group showed impaired memory in MWM test compared to the control group. Additionally, D-gal treatment resulted in an increase in IL-1β and TNF-α levels and a decrease in IL-6 levels, which was not statistically significant. However, the TNF-α level was significantly decreased in D-gal + L. rhamnosus-treated group compared to D-gal-only treated group (P < 0.05). Also, IL-6 level was significantly lower in D-gal + L. rhamnosus-treated group compared to control group (P < 0.05). These results suggest that the domestic L. rhamnosus might positively impact cognitive deficit and neuroinflammation. Further studies are suggested to investigate the specific mechanisms mediating the effects of L. rhamnosus on cognitive functions and neuroinflammation in animal models of AD.