PPARG and polycystic ovary syndrome: On the contrary, Jansen et al. identified PPARγ as upregulated in PCOS ovaries [53], while Kohan et al. described significantly higher PPARγ gene and protein levels, accompanied by decreased solute carrier family 2 member 4 (SLC2A4) levels, in endometrial tissue of women with PCOS and hyperinsulinemia [54].