The Cardiotonic Steroid Marinobufagenin Is a Predictor of Increased Left Ventricular Mass in Obesity: The African-PREDICT Study
NUTRIENTS
Authors: Strauss-Kruger, Michel; Kruger, Ruan; Smith, Wayne; Gafane-Matemane, Lebo F.; Mokwatsi, Gontse; Wei, Wen; Fedorova, Olga V.; Schutte, Aletta E.
Abstract
The endogenous Na+/K+-ATPase inhibitor, marinobufagenin (MBG), strongly associates with salt intake and a greater left ventricular mass index (LVMi) in humans and was shown to promote cardiac fibrosis and hypertrophy in animals. The adverse effects of MBG on cardiac remodeling may be exacerbated with obesity, due to an increased sensitivity of Na+/K+-ATPase to MBG. This study determined whether MBG is related to the change in LVMi over time in adults with a body mass index (BMI) >= 30 kg/m(2) (obese) and <30 kg/m(2) (non-obese). The study followed 275 healthy participants (aged 20-30 years) from the African-Prospective study on the Early Detection and Identification of Cardiovascular disease and Hypertension (African-PREDICT) study over 4.5 years. At baseline, we measured 24 h urine MBG excretion. MBG levels were positively associated with salt intake. LVMi was determined by two-dimensional echocardiography at baseline and after >4.5 years. With multivariate adjusted analyses in obese adults (N = 56), we found a positive association of follow-up LVMi (Adjusted (Adj.) R-2 = 0.35; Std. beta = 0.311; p = 0.007) and percentage change in LVMi (Adj. R-2 = 0.40; Std. beta = 0.336; p = 0.003) with baseline MBG excretion. No association of LVMi (Adj. R-2 = 0.37; p = 0.85) or percentage change in LVMi (Adj. R-2 = 0.19; p = 0.68) with MBG excretion was evident in normal weight adults (N = 123). These findings suggest that obese adults may be more sensitive to the adverse cardiac effects of MBG and provide new insight into the potential role of dietary salt, by way of MBG, in the pathogenesis of cardiac remodeling in obese individuals.
Hormonal Contraceptives and Dermatology
AMERICAN JOURNAL OF CLINICAL DERMATOLOGY
Authors: Williams, Natalie M.; Randolph, Michael; Rajabi-Estarabadi, Ali; Keri, Jonette; Tosti, Antonella
Abstract
Hormones play a significant role in normal skin physiology and many dermatologic conditions. As contraceptives and hormonal therapies continue to advance and increase in popularity, it is important for dermatologists to understand their mechanisms and dermatologic effects given the intricate interplay between hormones and the skin. This article reviews the dermatologic effects, both adverse and beneficial, of combined oral contraceptives (COCs), hormonal intrauterine devices (IUDs), implants, injections, and vaginal rings. Overall, the literature suggests that progesterone-only methods, such as implants and hormonal IUDs, tend to trigger or worsen many conditions, including acne, hirsutism, alopecia, and even rosacea. Therefore, it is worthwhile to obtain detailed medication and contraceptive histories on patients with these conditions. There is sufficient evidence that hormonal contraceptives, particularly COCs and vaginal rings, may effectively treat acne and hirsutism. While there are less data to support the role of hormonal contraceptives in other dermatologic disorders, they demonstrate potential in improving androgenetic alopecia and hidradenitis suppurativa.