Ovarian hormones and obesity

Area of Science:

• Endocrinology
• Obesity Research
• Neuroscience

Background:

• Severe obesity disproportionately affects women globally, with distinct pathophysiology and disease risks compared to men.
• Underlying mechanisms for sex-based differences in obesity are not fully understood, but ovarian hormones are implicated.
• Pre-clinical and clinical research suggests a significant role for ovarian hormones in obesity development and consequences.

Purpose of the Study:

• To systematically review the literature on ovarian hormone effects on adipose tissue physiology and body mass regulation.
• To identify emerging research areas with clinical translational potential regarding female obesity.
• To explore the impact of ovarian hormones on energy intake and expenditure in women.

Main Methods:

• Systematic literature search of PubMed (up to January 2016) using keywords for reproductive hormones, weight regulation, and the central nervous system.
• Focused on emerging research with clinical translational potential rather than exhaustive review.
• Included both pre-clinical and clinical studies.

Main Results:

• Estrogens play a key role in female obesity, influencing fat distribution (more gluteofemoral, less central in reproductive years) and offering cardiometabolic protection.
• Menopause-associated estrogen loss increases total adipose tissue and decreases lean mass, altering body composition, effects potentially reversible with estrogen therapy.
• Estrogens decrease eating via central mechanisms (e.g., enhancing cholecystokinin satiety) and affect food preferences; progestins may influence binge eating.
• Genetic defects in MC4R signaling exacerbate obesity in females, suggesting ovarian hormone influence around puberty.
• Brain imaging shows ovarian hormones modulate eating through dopaminergic and prefrontal cortex pathways; research on post-menopausal eating control and energy expenditure is limited.

Conclusions:

• The significant obesity burden in women necessitates urgent research into ovarian hormone effects on appetite, energy expenditure, and adiposity.
• Investigating these hormonal roles using diverse research modalities, including animal models, is vital.
• Intensified human and translational research is needed to uncover mechanistic insights for novel anti-obesity therapies to improve women's health.