Sex differences in myocardial metabolism and cardiac function: an emerging concept

Abstract

There is substantial evidence that there are dramatic sex-related differences in the incidence of cardiovascular disease, apparently related to the presence of steroid hormones. This is supported by the discovery of steroid hormone receptors in the heart and vasculature. More controversial is the area of sex-related differences in cardiac metabolism and function. A number of human and animal studies have demonstrated that estrogen and testosterone have cardiac metabolic effects. Additionally, research shows females have higher heart rates and various indices of function, including cardiac output and stroke volume, compared with males. However, some controversy exists, as other studies report that function in isolated muscle preparations is lower in females versus males. The reasons for these differences may reflect effects of sex hormones that are dependent on the conditions being studied. Cardiac function is reduced in postmenopausal females, suggesting that female sex hormones, specifically estrogen and progesterone, influence cardiac function. Apart from its well-documented vasodilatory effects, estrogen has also been shown to have negative inotropic effects and to reduce Ca(2+) transients in cardiomyocytes. Similar results have been found for progesterone. Several studies show that testosterone administration appears to increase cardiac performance, while others show that it increases the stiffness of the ventricle due to increased collagen synthesis, thereby reducing diastolic performance. This review will discuss current evidence suggesting sex-related differences in cardiac metabolism and its energetics and function and will present the potential role of the principal sex steroid hormones.

Probability of detection of clinical seizures using heart rate changes

“…The significant (p < 0.001) dependency of the probability of detection of clinical seizures using heart rate on factors such as age and gender [23][24][25][26], should be taken into account in the design of algorithms for automated seizure detection since they are likely to introduce volatility into their performance. Explicitly, females have higher heart rates, cardiac output and stroke volume [26] than males so that if heart rates applicable to females are used as reference for seizure detection in males or vice-versa, degradation in seizure detection performance is likely to occur. That in this study, in which no adjustments were made for gender differences in heart rate, seizure detection probability was lower in females compared to males, points to the importance of gender-specific adaptations.…”

PDK4 Inhibits Cardiac Pyruvate Oxidation in Late Pregnancy

“…33 But the effects of progesterone on cardiac metabolism have not been studied. 34 Progesterone is widely used clinically, usually in combination with estrogen, as hormone-replacement therapy (HRT) in peri-menopausal women. We find that such a combination also induces PDK4 in cardiac cells both in cell culture and in vivo.…”

Acyl CoA synthetase-1 links facilitated long chain fatty acid uptake to intracellular metabolic trafficking differently in hearts of male versus female mice

“…The impact of lipid metabolism based sex differences on cardiac pathology or conditions of metabolic stress have only recently been studied [21,23,49]. Peterson et al, demonstrated female sex was an independent predictor of palmitate uptake and utilization in healthy and obese subjects [22].…”