PPARA and obesity due to melanocortin 4 receptor deficiency: CGA notably inhibits the activities of FAS, HMGCR, and ACAT, and boosts the expression of PPARα in the liver [33], also inhibiting HMGCoA activity and enhancing CPT activity by activating AMPK, thus promoting lipid metabolism, reducing TC synthesis, and attenuating fat absorption to combat obesity [34].