Chung-Lin Chen, Pei-Yu Li, Hao-Yeh Tsai, Jue-Fang Chen, Yun-Chen Wang, Yi-Chun Lin, Yen-Shuo Lai, Syuan-Rong Chen, Yu-Min Kuo, Shun-Fen Tzeng, Po-See Chen, Shi-Bing Yang, Ching-Han Lin, Pei-Chun Chen
Metabolic stress and neuroinflammation are associated with depression, but the mechanisms connecting peripheral metabolic dysfunction to reward-related circuit alterations remain incompletely understood. ATP-sensitive potassium (KATP) channels couple cellular energy state to neuronal excitability and may link metabolic and neuroimmune signaling. Here, we used female mice exposed to post-weaning isolation combined with a high-fat diet to model convergent psychosocial and metabolic stress. We tested whether KATP channel modulation is associated with behavioral, inflammatory, and dopaminergic-marker changes under this combined stress condition. Peripheral KATP channel modulation was achieved by interscapular brown adipose tissue infusion of glibenclamide, and dopaminergic neuron-specific Kir6.2 conditional knockout mice were used to assess the contribution of neuronal KATP channel signaling. Combined stress induced obesity, hyperglycemia, depression-like behavioral alterations, peripheral cytokine imbalance, increased inflammatory markers, and reduced dopaminergic activity markers in the mesolimbic pathway. Glibenclamide improved glucose tolerance, attenuated stress-associated behavioral and inflammatory-marker changes, and increased Fos expression under stress conditions, while enhancing SUR1 maturation and surface localization. Kir6.2 deletion attenuated stress-associated behavioral alterations and reduced nucleus accumbens Iba1-positive cell accumulation, whereas effects on ventral tegmental area tyrosine hydroxylase-positive cell density were more modest. Together, these findings support KATP channel functional state as a candidate link between metabolic stress, neuroimmune alterations, and dopaminergic circuit adaptations in female mice, and suggest KATP channel modulation as a potential therapeutic strategy for metabolic-associated depression.