Human cells involved in atherosclerosis have a sex

The influence of sex has been largely described in cardiovascular diseases. Atherosclerosis is a complex process that involves many cell types such as vessel cells, immune cells and endothelial progenitor cells; however, many, if not all, studies do not report the sex of the cells. This review focuses on sex differences in human cells involved in the atherosclerotic process, emphasizing the role of sex hormones. Furthermore, we report sex differences and issues related to the processes that determine the fate of the cells such as apoptotic and autophagic mechanisms. The analysis of the data reveals that there are still many gaps in our knowledge regarding sex influences in atherosclerosis, largely for the cell types that have not been well studied, stressing the urgent need for a clear definition of experimental conditions and the inclusion of both sexes in preclinical studies.

Gender differences in the risk factors for endothelial dysfunction in Chinese hypertensive patients: homocysteine is an independent risk factor in females

Objectives

Endothelial dysfunction plays a key role in the pathogenesis of cardiovascular disease. However, the gender-related differences in risk factors for endothelial dysfunction are controversial. We investigated the gender differences in the risk factor profiles for endothelial dysfunction in Chinese hypertensive patients.

Methods

Vascular endothelial functions in 213 hypertensive patients were measured by digital reactive hyperemia peripheral arterial tonometry (RH-PAT). Peripheral blood samples were collected, and the self-reported smoking and alcohol consumption status, age, body mass index, heart rate, blood pressure and drug administrations were recorded.

Results

RH-PAT indexes were attenuated in both male and female hypertensive patients [1.60 (1.38-2.02) vs. 1.63 (1.44-1.98)]. Multivariate logistic regression analysis identified plasma creatinine (p < 0.001), total cholesterol (p = 0.001), homocysteine (p = 0.002) and smoking (p < 0.001) as the independent factors correlated with gender (male). Multivariate linear regression analysis further identified homocysteine as the factor that is significantly and independently correlated with the decrease in the RH-PAT indexes in female patients (odds ratio: -0.166, 95% confidence interval: -0.292 to -0.040, p = 0.01). However, none of these four factors were correlated with the RH-PAT indexes in male patients.

Conclusions

There are gender-related differences in the risk factors for endothelial dysfunction in Chinese hypertensive patients. Homocysteine is an independent factor for endothelial dysfunction in female hypertensive patients.

The effects of gender difference on monocrotaline-induced pulmonary hypertension in rats

The present study aimed to compare the effect of gender difference on hemodynamic consequences in the development of monocrotaline (MCT)-induced pulmonary hypertension in rat. The effect of antioxidant enzyme systems on the development of pulmonary hypertension mediated by the phytotoxin MCT and the effect of gender on these antioxidant systems were also investigated. For this purpose, the right ventricular pressures (RVPs) and right ventricular/heart weight (HW) ratios were compared between groups and the glutathione (GSH) level and superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST) activities were determined in lung and liver tissue samples of rats. RVP and right ventricular/HW ratios significantly increased in the MCT group compared to the control group. In the MCT group, RVP was significantly higher in males than females. MCT-induced pulmonary hypertension resulted in decreased GSH level, decreased GST and SOD activities and increased CAT activity in lung and liver tissues of both male and female rats. In addition, the lung and liver GSH level and GST and SOD levels were higher in female control rats compared to male control rats. The results of the present study, that antioxidant enzyme activities were different between the groups, highlight the possible role of oxidative stress in the pathogenesis of MCT-induced pulmonary hypertension in rats. Moreover, the lower antioxidant defense capacity of male rats than female rats may be considered as a cause of more aggressive course of MCT-induced pulmonary hypertension in males compared to females.

Gender difference in albuminuria and ischemic heart disease in type 2 diabetes

OBJECTIVE

The value of urinary albumin excretion in the prediction of myocardial ischemia in men and women with type 2 diabetes is not well understood. We questioned whether gender influences the albuminuria-ischemic heart disease relationship in patients with type 2 diabetes.

METHODS

We designed a matched case-control study of 926 patients with albuminuria (cases) and 926 age and body mass index matched patients without albuminuria (controls). Ischemic heart disease was defined as the presence of (1) history of angina pectoris or angina equivalent symptoms and critical care unit admission, (2) myocardial infarction and/or electrocardiographic evidence of Q-wave myocardial infarction, (3) coronary revascularization and/or stenting, (4) positive myocardial single-photon emission computed tomography scan, (5) ischemic ST-segment or T-wave changes, and (6) positive stress testing.

RESULTS

Patients with albuminuria had a lower glomerular filtration rate and a longer diabetes duration than patients without albuminuria. In the group of cases, there were a greater number of men with ischemic heart disease (120 of 370; 32.4%) compared to women (97 of 559; 17.4%) (P<0.001). The odds ratio of having ischemic heart disease according to the presence or absence of albuminuria was 1.25 [95% CI: 1.01-1.56] (P<0.05) in all studied populations, 0.79 [95% CI: 0.51-1.21] (P=0.14) in women, and 2.84 [95% CI: 1.68-4.79] (P<0.001) in men. We showed that diabetes duration, high-density lipoprotein, low-density lipoprotein, and hemoglobin A(1c) influence albuminuria in women, while diabetes duration, fasting blood sugar, and diastolic blood pressure influence albuminuria in men.

CONCLUSIONS

Men with albuminuria are at increased risk of ischemic heart disease compared to women. This may be related to the role of high-density lipoprotein on the albuminuria-gender relationship.