HIF1A and obesity due to melanocortin 4 receptor deficiency: Furthermore, mice with macrophage-specific deletion of HIF-1α partially mirrored the phenotypes of our obese adipocyte-selective Ldha KO mice, in that both mice exhibited reduced levels of local and systemic IL-1β37, consistent with the notion that myeloid HIF-1α activation in obese adipose tissue, where inflammatory stimuli predominate, positively drives inflammation in obesity.