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

## TL;DR

This study shows that progesterone increases metallothionein gene expression in rat inguinal fat, but only in females.

## Contribution

The novel finding is the gender-dependent effect of progesterone on metallothionein gene expression in rat adipose tissue.

## Key findings

- Progesterone increased MT-1 and MT-2A mRNA and protein levels in female rat inguinal adipose tissue.
- RU 486 blocked progesterone's effect on Mt-1 and Mt-2A gene expression in female rats.
- Progesterone had no effect on Mt-3 or other adipose tissues in females.

## Abstract

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 Mt 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 Mt-1 and Mt-2A gene expression in female WATi. Progesterone administration did not alter the level of Mt-3 gene expression in WATi or Mt-1 and Mt-2A in retroperitoneal WAT or brown adipose tissue in female rats.