Gender-Dependent Effect of Progesterone on the Expression of Metallothionein Genes in Rat Inguinal Adipose Tissue

Metallothioneins (MTs) are low-molecular-weight metal-binding proteins potentially involved in the detoxification of heavy metals, protection against oxidative stress, and other biological processes. This study examined progesterone's influence on <i>Mt</i> gene expression in rat adipose tissue. Wistar rats (females and males) received 100 mg of progesterone per rat. MT mRNA and protein levels were quantified by real-time PCR and Western blotting methods. Using radioimmunoassay, the serum progesterone level was measured. In this study, progesterone administration to female rats led to a 2.5-fold increase in serum progesterone concentration and significant increases in MT-1, MT-2A mRNA, and protein levels in inguinal WAT (WATi), compared to untreated female rats. RU 486 (progesterone receptor antagonist) abolished progesterone's influence on <i>Mt-1</i> and <i>Mt-2A</i> gene expression in female WATi. Progesterone administration did not alter the level of <i>Mt-3</i> gene expression in WATi or <i>Mt-1</i> and <i>Mt-2A</i> in retroperitoneal WAT or brown adipose tissue in female rats.