PPARG and obesity due to melanocortin 4 receptor deficiency: For example, astaxanthin decreased myeloperoxidase and nitric oxide synthases and made splenocytes less sensitive to lipopolysaccharide stimulation [20]; increased the usage of lipids during exercise [21]; and was a novel selective peroxisome proliferator-activated receptor gamma (PPAR-γ) modulator that acted as an antagonist or agonist to exert its ameliorative effects on obesity and insulin resistance [22].