Testosterone-Dependent Regulation of Arachidonic Acid Metabolism Influences the Development of Hypertension Following Insulin Resistance

Resistance to insulin — the hormone that converts sugar into energy — leads to diabetes and high blood pressure (hypertension). Chronic hypertension can lead to cardiovascular complications like heart disease and stroke — two leading causes of death. This is a cause for concern since two million Canadians have diabetes, and this number is expected to rise to three million by the end of the decade. Consuming a diet high in fructose, a sugar used to sweeten soft drinks and other foods, causes insulin resistance and increases blood pressure. Harish Vasudevan has found that differences in gender and sex hormones play a role in the development of high blood pressure. For example, pre-menopausal women are less likely to develop hypertension than men or post-menopausal women. The female sex hormone, estrogen, protects these women against developing insulin resistance and high blood pressure. But the male sex hormone, testosterone, is required for blood pressure to elevate following insulin resistance. Fructose also disturbs the normal relaxation in blood vessels, but requires testosterone to do so. Vasudevan is examining how changes in the blood vessels depend on testosterone and estrogen. This research will further clarify the role of sex hormones in the development of insulin resistance and hypertension, which should, in turn, lead to new treatments for these chronic diseases.