HMOX1 and obesity due to melanocortin 4 receptor deficiency: In the study, poly(lactic-co-glycolic acid) (PLGA) NPs were loaded with heme oxygenase-1 (HO-1) inducers (iron protoporphyrin ix (hemin) or cobalt protoporphyrin ix (CoPP)) and surface modified with AHP then used for the treatment of obesity-induced T2DM and diet-induced MASH in mice models.