PPARG and lipodystrophy: Correspondingly, if the tissue sample was obtained at an advanced stage of lipodystrophy, the expression of complement genes may be significantly influenced by down-regulation of PPARG and CEBPA. However, the elevated expression of C5 (Table 2), a gene not controlled by PPARG, may suggest that upregulation of complement-related genes is a chronic phenomenon occurring before and during adipose tissue damage.