Organ-Specific Modulation of IGF-Binding Proteins in Malnourished Mice Supplemented with Probiotics: A Proteomic Approach

Malnutrition disrupts the insulin-like growth factor (IGF) axis, impairing systemic growth and brain function. This study quantitatively assessed IGF-binding protein (IGFBP) expression in the liver and brain of malnourished mice following probiotic supplementation. Male BALB/c mice were subjected to a low-protein diet to induce malnutrition, then divided into probiotic and control groups. Proteomic profiling using the Mouse XL Cytokine Array (R&D Systems, ARY028) revealed organ-specific differences. In the liver, probiotics markedly increased IGFBP-3 (net intensity 3000 AU) and reduced IGFBP-1 (1200 AU) compared with malnourished controls, while maintaining IGFBP-2 (2500 AU). In the brain, probiotics induced IGFBP-5 (1,800 AU) and IGFBP-6 (1,500 AU), both of which were absent in controls, alongside a moderate IGFBP-2 signal (2,200 AU). These quantitative findings indicate that probiotics selectively enhance hepatic IGF-1 stabilization via IGFBP-3 while promoting neurotrophic support through IGFBP-5 and IGFBP-6. The results highlight the potential of probiotics as an adjunctive strategy to restore growth and neurological function in malnutrition.