Chronic stress, but not hypercaloric diet, impairs vascular function in rats

Area of Science:

• Endocrinology
• Cardiovascular Physiology
• Metabolic Syndrome Research

Background:

• Chronic mild stress (CMS) and hypercaloric diets (HD) are prevalent in modern lifestyles.
• Both factors are implicated in metabolic and cardiovascular disturbances.
• Understanding their independent and combined effects is crucial for public health.

Purpose of the Study:

• To investigate the vascular and metabolic impacts of CMS and HD in rats.
• To determine if CMS exacerbates diet-induced metabolic changes.
• To assess the effects on aortic vascular function and morphology.

Main Methods:

• Male Sprague-Dawley rats were divided into Control, HD, CMS, and HD+CMS groups.
• CMS involved applying various stressors for 3 weeks.
• Vascular function, glucose metabolism, and plasma lipid profiles were analyzed post-stress.

Main Results:

• HD alone induced dyslipidemia but did not alter glucose metabolism or vascular parameters.
• CMS elevated plasma corticosterone, lipids, insulin, and atherogenic index.
• CMS increased aortic intima-media thickness and impaired endothelium-dependent relaxation, independent of diet.

Conclusions:

• CMS significantly contributes to vascular dysfunction in the thoracic aorta.
• Stress-induced metabolic and hormonal changes are key drivers of aortic impairment.
• CMS poses a significant risk to cardiovascular health, irrespective of dietary habits.