Cross-sex hormonal replacement: Some effects over mitochondria

Area of Science:

• Endocrinology
• Cardiovascular Biology
• Mitochondrial Medicine

Background:

• Transgender individuals may undergo cross-hormonal therapy to align gender identity with physical characteristics.
• Hormone replacement therapy, using estrogens and testosterone, is associated with potential side effects including cardiovascular risks.
• The impact of cross-sex hormones on heart mitochondrial function and metabolic perturbations in the transgender community remains understudied.

Purpose of the Study:

• To investigate the effects of cross-sex hormone administration on heart mitochondrial function.
• To analyze alterations in mitochondrial respiration, calcium handling, and oxidative stress markers.

Main Methods:

• Female rats were gonadectomized and administered testosterone; male rats were gonadectomized and administered estrogens for four months.
• Electrocardiograms were performed to assess cardiac electrical activity.
• Heart mitochondria were isolated to measure oxygen consumption, calcium fluxes, membrane potential, superoxide dismutase activity, lipoperoxidation, and cytokine levels.

Main Results:

• Cross-hormonal administration led to significant modifications in all measured cardiac mitochondrial parameters.
• Observed changes included altered oxygen consumption rates, calcium handling, membrane potential, and increased oxidative stress markers.
• Cytokine levels were also affected by the cross-hormonal treatment.

Conclusions:

• Cross-sex hormone administration significantly alters heart mitochondrial function in a rodent model.
• These findings suggest potential mechanisms for the cardiovascular side effects associated with hormone replacement therapy in transgender individuals.
• Further research is warranted to elucidate the long-term clinical implications for cardiovascular health in the transgender population.