LEP and obesity due to melanocortin 4 receptor deficiency: Indeed, the genus Bacteroides was negatively correlated with the gene expression of hypothalamic PPAR-γ, which contributes to HFD-induced leptin resistance (Ryan et al., 2011), a condition that leads to the development of obesity and metabolic disorders, such as insulin resistance and dyslipidemia (Gruzdeva et al., 2019).