Testosterone and secondary hypertension: new pieces to the puzzle

Association between life's essential 8 and male biochemical androgen deficiency: evidence from NHANES 2013-2016

Purpose

To evaluate the association of Life's Essential 8 (LE8) and its subscales with male biochemical androgen deficiency (MBAD) and total testosterone based on the data from the national health and nutrition examination survey (NHANES) database.

Methods

Data of males aged 20 years or older from NHANES of 2013-2016 were extracted. LE8 score was calculated based on American Heart Association definitions. Total testosterone (TT) values were measured in NHANES using precise isotope dilution liquid chromatography. MBAD was defined as serum TT of <300 ng/dL. Univariate and multivariable analyses were conducted. Propensity score matching (PSM) and weighted regression after matching were added as sensitivity analyses. The generalized additive model, smooth curve fitting, and the recursive algorithm were used to determine the potential inflection points. Piecewise regression models with log-likelihood ratio test were used to quantify nonlinear effects.

Results

A total of 3094 participants who were males and aged 20 years or above were included. Out of them, 805 males were diagnosed with MBAD. After adjusting the confounders in the multivariable model, LE8 was independently associated with MBAD (OR 0.96, P < 0.001) and TT (β 2.7, P < 0.001). The association remained robust even after PSM. The non-linear relationship of LE8 behaviors score with MBAD and TT was revealed.

Conclusion

LE8 was an independent protective factor of MBAD and a feasible approach to promote male endocrine sexual function.

Sex and sex steroids as determinants of cardiovascular risk

There are considerable sex differences regarding the risk of cardiovascular disease (CVD), including arterial hypertension, coronary artery disease (CAD) and stroke, as well as chronic renal disease. Women are largely protected from these conditions prior to menopause, and the risk increases following cessation of endogenous estrogen production or after surgical menopause. Cardiovascular diseases in women generally begin to occur at a later age than in men (on average with a delay of 10 years). Cessation of estrogen production also impacts metabolism, increasing the risk of developing obesity and diabetes. In middle-aged individuals, hypertension develops earlier and faster in women than in men, and smoking increases cardiovascular risk to a greater degree in women than it does in men. It is not only estrogen that affects female cardiovascular health and plays a protective role until menopause: other sex hormones such as progesterone and androgen hormones generate a complex balance that differentiates heart and blood vessel function in women compared to men. Estrogens improve vasodilation of epicardial coronary arteries and the coronary microvasculature by augmenting the release of vasodilating factors such as nitric oxide and prostacyclin, which are mechanisms of coronary vasodilatation that are more pronounced in women compared to men. Estrogens are also powerful inhibitors of inflammation, which in part explains their protective effects on CVD and chronic renal disease. Emerging evidence suggests that sex chromosomes also play a significant role in shaping cardiovascular risk. The cardiovascular protection conferred by endogenous estrogens may be extended by hormone therapy, especially using bioidentical hormones and starting treatment early after menopause.

Pre-bout hypertension in the combat sports athlete: clearance recommendations

Hypertension is one of the most prevalent medical disorders in the world and is associated with significant cerebrovascular and cardiovascular morbidity. Pre-bout blood pressure (BP) elevation is extremely common, and ringside physicians must accurately assess the accompanying risk of adverse cerebrovascular and cardiovascular events in the decision to allow participation in combat sports. It is strongly recommended that a ringside physician consider disqualifying a combat sports athlete with severe pre-bout hypertension (systolic BP ≥160 mm Hg and/or diastolic BP ≥100 mm Hg, or stage 2 hypertension in children when indexed by gender, age, and height) from that bout, if it persists despite rest and repeated measurement with accurate equipment. This recommendation is congruent with that of the American College of Sports Medicine, the American College of Cardiology, and the American Heart Association, which recommend non-clearance for sports or exercise testing when BP exceeds those thresholds. Severely elevated BP, as defined above, confers markedly increased risk of morbidity and mortality. Exercise further raises BP markedly. The combination of severely elevated blood pressure and cranial trauma during combat sports is a risk factor for intracranial hemorrhage with a direct impact on the morbidity and mortality associated with ringside combat sports events. Combat sports athletes with SBP ≥130 or DBP ≥90 - and their coaches and families, if available and the athlete consents - should be educated on the causes of hypertension, its acute and chronic risks, and the possible future implications for bout clearance, and the athletes should be referred for evaluation and management.

Testosterone therapy and cardiovascular diseases

Since it was first synthesised in 1935, testosterone (T) has been viewed as the mythical Fountain of Youth, promising rejuvenation, restoring sexual appetites, growing stronger muscles, and quicker thinking. T is endowed with direct effects on myocardial and vascular structure and function, as well as on risk factors for cardiovascular (CV) disease. Indeed, low serum T levels are a risk factor for diabetes, metabolic syndrome, inflammation, and dyslipidaemia. Moreover, many studies have shown that T deficiency per se is an independent risk factor of CV and all-cause mortality. On this background and due to direct-to-patient marketing by drug companies, we have witnessed to the widespread use of T replacement therapy (TT) without clear indications particularly in late-life onset hypogonadism. The current review will dwell upon current evidence and controversies surrounding the role of T in the pathophysiology of CV diseases, the link between circulating T levels and CV risk, and the use of replacing T as a possible adjuvant treatment in specific CV disorders. Specifically, recent findings suggest that heart failure and type 2 diabetes mellitus represent two potential targets of T therapy once that a state of hypogonadism is diagnosed. However, only if ongoing studies solve the CV safety issue the T orchid may eventually 'bloom'.

SWIM TRAINING REVERSES SOME EFFECTS OF NANDROLONE DECANOATE IN WISTAR RATS

ABSTRACT Introduction: The indiscriminate use of androgenic steroids may have deleterious effects on human tissue. Objectives: Evaluate the effects of chronic administration of the steroid nandrolone decanoate (DECA) on autonomic cardiovascular modulation, kidney morphometry and the association between these variables in Wistar rats subjected to physical training with swimming. Methods: Thirty-two male Wistar rats aged 20 weeks were distributed among four experimental groups according to the training received: sedentary control (SC), sedentary treated with DECA (SD), trained control (TC) and trained treated with DECA (TD). The hemodynamic parameters, including blood pressure and variations in systolic blood pressure (SBPV) and diastolic blood pressure (DBPV), and kidney morphometry were evaluated. The level of significance adopted was 5%. Results: The SD group had higher baseline SBP and DBP values when compared to the SC, TC and TD groups, which were similar to each other. The rats in the SD group had higher systolic blood pressure (SBPV) and diastolic blood pressure (DBPV) variation values and higher absolute and normalized values in the LF band of the DBPV when compared to the animals in the SC, TC and TD groups. The animals in the SD group had a significantly higher rate of kidney fibrosis compared to the SC, TC and TD groups. There were no significant differences between the sympathetic modulation of SBPV through the LF component and kidney fibrosis. Conclusions: Physical training with swimming was effective in preventing the increase in blood pressure levels and lowering the occurrence of kidney fibrosis in animals treated with anabolic steroids. Level of Evidence IV; Series of cases .

Data science-driven analyses of drugs inducing hypertension as an adverse effect

The utilization of approved medication is a requisite to combat certain diseases for health; however, the undesirable adverse effects (AEs) due to medication are generally unavoidable. Hypertension is one of such AEs resulting from approved medication in which blood pressure in the arteries gets elevated and is a risk factor for several diseases including heart and kidney failure. HTs are the approved drugs that can cause hypertension as an AE. Here, the goal of the study is to investigate the structural and functional diversities of HTs. In our quest to unravel the structural parameters of the HTs, a systematic analysis of the HTs having a different number and type of ring systems was conducted. The cellular component, molecular function and biological processes adopted by the gene products were analyzed. Moreover, our systematically done analysis suggests that all the target families are active in a common pathway, that is, nerve transmission. A comparison of the selected structural and functional aspect of HTs with anti-hypertensives suggests that HTs follow certain structural and functional features in spite of many possibilities. Our study provides a promising methodology that considers the influence of structural diversity of AE causing agents on a functional perspective for precursory clinical decision making. This could be extended to explore the structural and functional trends that are adopted by agents causing certain diseases or AEs.

Drug-induced endocrine blood pressure elevation

Patients with uncontrolled hypertension are at risk for cardiovascular complications. The majority of them suffers from unidentified forms of hypertension and a fraction has so-called secondary hypertension with an identifiable cause. The patient's medications, its use of certain herbal supplements and over-the-counter agents represent potential causal factors for secondary hypertension that are often overlooked. The current review focuses on drugs that are likely to elevate blood pressure by affecting the human endocrine system at the level of steroid synthesis or metabolism, mineralocorticoid receptor activity, or by affecting the catecholaminergic system. Drugs with known adverse effects but where benefits outweigh their risks, drug candidates and market withdrawals are reviewed. Finally, potential therapeutic strategies are discussed.

Sodium acetate and androgen receptor blockade improve gestational androgen excess-induced deteriorated glucose homeostasis and antioxidant defenses in rats: roles of adenosine deaminase and xanthine oxidase activities

Nutritional challenges and androgen excess have been implicated in the development of gestational diabetes and poor fetal outcome, but the mechanisms are not well delineated. The effects of short chain fatty acid (SCFA) on glucose dysmetabolism and poor fetal outcome induced by gestational androgen excess is also not known. We tested the hypothesis that blockade of androgen receptor (AR) and suppression of late gestational androgen excess prevents glucose dysmetabolism and poor fetal outcome through suppression of adenosine deaminase (ADA)/xanthine oxidase (XO) pathway. Twenty-four pregnant Wistar rats were treated (sc) with olive oil, testosterone propionate (0.5 mg/kg) singly or in combination with SCFA (sodium acetate; 200 mg/kg; p.o.) or AR blocker (flutamide; 7.5 mg/kg; p.o.) between gestational days 14 and 19. The results showed that late gestational androgen excess led to glucose deregulation, poor fetal outcome, increased plasma and hepatic free fatty acid and lactate dehydrogenase, liver function marker enzymes, malondialdehyde, uric acid, ADA and XO activities. Conversely, gestational androgen excess resulted in reduced body weight gain, visceral adiposity, plasma and hepatic anti-oxidant defenses (glutathione peroxidase, reduced glutathione/glutathione disulphide ratio, glucose-6-phosphate dehydrogenase, adenosine and nitric oxide). However, all these effects were ameliorated by either sodium acetate or flutamide treatment. The study demonstrates that suppression of testosterone by SCFA or AR blockade protects against glucose deregulation and poor fetal outcome by improvement of anti-oxidant defenses and replenishment of hepatic oxidative capacity through suppression of ADA/XO pathway. Hence, utility of SCFA should be encouraged for prevention of glucose dysmetabolism and poor fetal outcome.

Nandrolone alter left ventricular contractility and promotes remodelling involving calcium-handling proteins and renin-angiotensin system in male SHR

AIMS

Hypertension is a highly prevalent disease that has been correlated to severe organ damage and mortality. However, the role of androgens in hypertension is controversial. The aim of this study was to evaluate the cardiac effects of the nandrolone decanoate (NDL) in male SHR.

MAIN METHODS

At 12 weeks of age, male SHR rats were separated into three groups: Control (CON), Nandrolone 10 mg/kg twice weekly (NDL), and NDL plus Enalapril 10 mg/kg/day (NDL-E) groups. The animals were treated for 4 weeks. Haemodynamic parameters were acquired through ventricular catheter implantation. The left ventricle was stained with haematoxylin/eosin or picrosirius red. Western blot analysis of TNF-α, ACE, AT₁R, β₁-AR, PLB, p-PLB^ser16 and SERCA2a was performed.

KEY FINDINGS

Nandrolone increased hypertension in SHR rats and enalapril reduced blood pressure to values below those of the control. NDL increased +dP/dt_max, -dP/dt_max and cardiac hypertrophy, which were prevented in the NDL-E group. Cardiac collagen deposition was increased in the NDL group, with this effect being attenuated by enalapril in NDL-E animals. TNF-α, ACE, AT₁R and β1-AR proteins were increased in the NDL, and enalapril decreased them, except for TNF-α. The ratio p-PLB^ser16/PLB revealed an increase after nandrolone, which was prevented in the NDL-E group. The SERCA2a expression protein and SERCA2a/PLB were increased in NDL animals, which did not occur in the NDL-E group.

SIGNIFICANCE

Nandrolone has distinct effects on cardiac function and remodelling in male SHR, altering the hypertension development process in the heart through modulation of calcium handling proteins and the renin-angiotensin system.

Association of sleep disturbances with obesity, insulin resistance and the metabolic syndrome

Insufficient sleep, which has become endemic in recent years, has been variably associated with increased risk of obesity, disorders of glucose and insulin homeostasis, and the metabolic syndrome; to a lesser degree, so has excessive sleep. This review summarizes recent epidemiological and pathophysiological evidence linking sleep disturbances (primarily abnormalities of sleep duration) with obesity, insulin resistance, type 2 diabetes and the metabolic syndrome in children and adults.

Reactive oxygen species: players in the cardiovascular effects of testosterone

Androgens are essential for the development and maintenance of male reproductive tissues and sexual function and for overall health and well being. Testosterone, the predominant and most important androgen, not only affects the male reproductive system, but also influences the activity of many other organs. In the cardiovascular system, the actions of testosterone are still controversial, its effects ranging from protective to deleterious. While early studies showed that testosterone replacement therapy exerted beneficial effects on cardiovascular disease, some recent safety studies point to a positive association between endogenous and supraphysiological levels of androgens/testosterone and cardiovascular disease risk. Among the possible mechanisms involved in the actions of testosterone on the cardiovascular system, indirect actions (changes in the lipid profile, insulin sensitivity, and hemostatic mechanisms, modulation of the sympathetic nervous system and renin-angiotensin-aldosterone system), as well as direct actions (modulatory effects on proinflammatory enzymes, on the generation of reactive oxygen species, nitric oxide bioavailability, and on vasoconstrictor signaling pathways) have been reported. This mini-review focuses on evidence indicating that testosterone has prooxidative actions that may contribute to its deleterious actions in the cardiovascular system. The controversial effects of testosterone on ROS generation and oxidant status, both prooxidant and antioxidant, in the cardiovascular system and in cells and tissues of other systems are reviewed.

Testosterone induces leucocyte migration by NADPH oxidase-driven ROS- and COX2-dependent mechanisms

The mechanisms whereby testosterone increases cardiovascular risk are not clarified. However, oxidative stress and inflammation seem to be determinants. Herein, we sought to determine whether exogenous testosterone, at physiological levels, induces leucocyte migration, a central feature in immune and inflammatory responses and the mediating mechanisms. We hypothesized that testosterone induces leucocyte migration via NADPH oxidase (NADPHox)-driven reactive oxygen species (ROS) and cyclooxygenase (COX)-dependent mechanisms. Sixteen-week-old Wistar rats received an intraperitoneal injection (5 ml) of either testosterone (10(-7) mol/l) or saline. Rats were pre-treated with 5 ml of sodium salicylate (SS, non-selective COX inhibitor, 1.25 × 10(-3) mol/l, 1 h prior to testosterone or saline), flutamide (androgen receptor antagonist, 10(-5) mol/l), apocynin (NADPHox inhibitor, 3 × 10(-4) mol/l), N-[2-Cyclohexyloxy-4-nitrophenyl]methanesulfonamide (NS398, COX2 inhibitor, 10(-4) mol/l) or saline, 4 h before testosterone or saline administration. Leucocyte migration was assessed 24 h after testosterone administration by intravital microscopy of the mesenteric bed. Serum levels of testosterone were measured by radioimmunoassay. NADPHox activity was assessed in membrane fractions of the mesenteric bed by dihydroethidium (DHE) fluorescence and in isolated vascular smooth muscle cells (VSMC) by HPLC. NADPHox subunits and VCAM (vascular cell adhesion molecule) expression were determined by immunoblotting. Testosterone administration did not change serum levels of endogenous testosterone, but increased venular leucocyte migration to the adventia, NADPHox activity and expression (P < 0.05). These effects were blocked by flutamide. SS inhibited testosterone-induced leucocyte migration (P<0.05). Apocynin and NS398 abolished testosterone-induced leucocyte migration and NADPHox activity (P<0.05). Testosterone induces leucocyte migration via NADPHox- and COX2-dependent mechanisms and may contribute to inflammatory processes and oxidative stress in the vasculature potentially increasing cardiovascular risk.

Beneficial and adverse effects of testosterone on the cardiovascular system in men

CONTEXT

The widespread use of T therapy, particularly in aging males, necessitates knowledge of the relationship between T and the cardiovascular system.

EVIDENCE ACQUISITION

The review is based on a 1970 to 2013 PubMed search with terms related to androgens in combination with cardiovascular disease, including T, dihydrotestosterone, trial, mortality, cardiovascular disease, myocardial infarction, blood pressure, endothelial function, dyslipidemia, thrombosis, ventricular function, and arrhythmia. Original articles, systematic reviews and meta-analyses, and relevant citations were screened.

EVIDENCE SYNTHESIS

Low T has been linked to increased blood pressure, dyslipidemia, atherosclerosis, arrhythmia, thrombosis, endothelial dysfunction, as well as to impaired left ventricular function. On the one hand, a modest association is suggested between low endogenous T and incident cardiovascular disease or cardiovascular mortality, implying unrecognized beneficial T effects, residual confounding, or a relationship with health status. On the other hand, treatments with T to restore "normal concentrations" have so far not been proven to be beneficial with respect to cardiovascular disease; neither have they definitely shown specific adverse cardiovascular effects. The cardiovascular risk-benefit profile of T therapy remains largely evasive in view of a lack of well-designed and adequately powered randomized clinical trials.

CONCLUSIONS

The important knowledge gap as to the exact relationship between T and cardiovascular disease would support a cautious, restrained approach to T therapy in aging men, pending clarification of benefits and risks by adequately powered clinical trials of sufficient duration.

Testosterone enhances tubuloglomerular feedback by increasing superoxide production in the macula densa

Males have higher prevalence of hypertension and renal injury than females, which may be attributed in part to androgen-mediated effects on renal hemodynamics. Tubuloglomerular feedback (TGF) is an important mechanism in control of renal microcirculation. The present study examines the role of testosterone in the regulation of TGF responses. TGF was measured by micropuncture (change of stop-flow pressure, ΔPsf) in castrated Sprague-Dawley rats. The addition of testosterone (10(-7) mol/l) into the lumen increased the ΔPsf from 10.1 ± 1.2 to 12.2 ± 1.2 mmHg. To determine whether androgen receptors (AR) are involved, mRNA of AR was measured in the macula dense cells isolated by laser capture microdissection from kidneys, and a macula densa-like cell line (MMDD1). AR mRNA was expressed in the macula densa of rats and in MMDD1 cells. We next examined the effects of the AR blocker, flutamide (10(-5) mol/l) on the TGF response. The addition of flutamide blocked the effects of testosterone on TGF. The addition of Tempol (10(-4) mol/l) or polyethylene glycol-superoxide dismutase (100 U/ml) to scavenge superoxide blocked the effect of testosterone to augment TGF. We then applied apocynin to inhibit NAD(P)H oxidase and oxypurinol to inhibit xanthine oxidase and found the testosterone-induced augmentation of TGF was blocked. In additional experiments in MMDD1 cells, we found that testosterone increased O2(-) generation. Apocynin or oxypurinol blocked the testosterone-induced increases of O2(-), while blockade of COX-2 with NS-398 had no effect. These findings suggest that testosterone enhances TGF response by stimulating O2(-) production in macula densa via an AR-dependent pathway.