Sialyllactose Alleviates Streptozotocin-Induced Diabetes through Anti-Inflammatory and Metabolic Modulation

Diabetes mellitus (DM) is a disorder characterized by hyperglycemia, inflammation, and impaired metabolic activities. This study investigated the effects of sialyllactose (SL), a subgroup of human milk oligosaccharides, on streptozotocin (STZ)-induced type 1 diabetes mellitus (T1DM) <i>in vivo</i>. Male ICR mice were preadministered SL followed by a single intraperitoneal injection of STZ to establish the T1DM model. The evaluation was conducted through biochemical analyses, glucose and insulin tolerance tests, histological assessments, qRT-PCR, and western blotting. We found that SL pretreatment improved body weight, glucose tolerance, and fasting blood glucose levels in mice. SL mitigated STZ-induced organ injury, as evidenced by histological analysis and serum markers of liver, pancreas, kidney, and skeletal muscle damage. SL also improved electrolyte and lipid profiles, indicating its role in metabolism. Notably, SL exhibited strong anti-inflammatory properties by inhibiting hepatic TNF-α and MCP-1 mRNA expression and reducing inducible nitric oxide synthase protein expression. Taken together, our findings suggest that SL is a promising candidate for DM management based on its beneficial effects on inflammation and metabolic modulation.