Preventive effects of GABA-producing postbiotics derived from Levilactobacillus brevis against chronic sleep deprivation-induced gut-brain axis dysfunction, neuroinflammation, and behavioral impairments in mice

Chronic sleep deprivation (CSD) is increasingly recognized as a contributor to gut dysbiosis, systemic inflammation, and neurobehavioral impairments via the gut-brain axis. γ-Aminobutyric acid (GABA)-producing postbiotics, derived from microbial fermentation, offer potential in mitigating such dysfunctions. This study investigates the effects of GABA-producing postbiotics produced by Levilactobacillus brevis on CSD-induced gut and brain disturbances in mice. Male C57BL/6 mice were subjected to 30 days of sleep fragmentation and treated with low (250 mg/kg) or high (500 mg/kg) doses of postbiotics. Behavioral tests revealed that GABA-producing postbiotics significantly alleviated anxiety- and depression-like behaviors. Postbiotic treatment restored intestinal tight junction protein expression (ZO-1, Claudin-1), increased glutathione peroxidase activity, and reduced serum lipopolysaccharide and TNF-α levels, indicating improved intestinal barrier function and attenuated systemic inflammation. Postbiotic treatment promote the growth of beneficial genera such as Ruminococcus and Akkermansia , while also elevating fecal propanoic acid concentrations. In the brain, postbiotics upregulated blood-brain barrier (BBB) associated genes and reduced neuroinflammatory gene expression. Correlation analysis highlighted microbial signatures linked to short-chain fatty acids, intestinal tight junction proteins, serum LPS and TNF-α levels, as well as hypothalamic inflammatory, BBB gene expressions and anxiety. These findings suggest that GABA-producing postbiotics ameliorate CSD-induced gut-brain axis disruption by modulating the microbiota, restoring barrier functions, and suppressing systemic and neuroinflammation. This study supports the potential application of GABA-producing postbiotics as a dietary strategy to mitigate sleep loss-related physiological and behavioral impairments. • GABA-producing postbiotics alleviated CSD-induced anxiety- and depression-like behaviors in mice. • Postbiotics restored gut tight junctions, enhanced GPx activity, and reduced serum LPS/TNF-α. • Postbiotics reshaped microbiota, increased fecal propanoic acid, and enriched Akkermansia. • Postbiotics upregulated blood-brain barrier genes and suppressed hypothalamic neuroinflammation.