Anabolic-androgenic steroids induce apoptotic cell death in adult rat ventricular myocytes

Effects of castration and testosterone replacement on the antioxidant defense system in rat left ventricle

There is strong evidence that oxidative stress plays a key role in the pathophysiology of several cardiovascular diseases. On the other hand, the presence of specific receptors for androgens and estrogens in the myocardium implies that sex hormones play a physiological role in cardiac function, myocardial injury, and the regulation of the redox state in the heart. The present study was designed to determine whether castration and androgen replacement result in changes in the capacity of the antioxidant defense system in the left ventricle (LV) of adult male rats. To assess this, the activities of antioxidant enzymes (superoxide dismutase [SOD], glutathione peroxidase [GPX], catalase [CAT], and glutathione reductase [GR]), concentrations of nonenzymatic antioxidants (reduced glutathione [GSH] and alpha- and gamma-tocopherols), and oxidative stress biomarkers (tissue sulfhydryl groups, protein nitrotyrosine levels, and lipid peroxidation) were measured in castrated animals (CAS), castrates replaced with testosterone (CAS+T), and sham-operated controls (Sham). Testosterone was not detectable in serum from gonadectomized rats. The results indicate that castration significantly and negatively affected the antioxidant status of rat LV, as evidenced by a significant decline in activities of all antioxidant enzymes, by a tendency toward lower levels of GSH and protein thiol groups, and by enhanced lipid peroxidation and higher nitrotyrosine concentrations in left ventricular tissue. Increases in LV tissue concentrations of alpha- and gamma-tocopherols seem to be a compensatory response to enhanced oxidative stress induced by gonadectomy. The reestablishment of physiological serum testosterone level by androgen replacement resulted in a tendency toward a further decrease in the antioxidant defense status in the LV tissue.

Anabolic steroids induce cardiac renin-angiotensin system and impair the beneficial effects of aerobic training in rats

We evaluated the effects of swimming and anabolic steroids (AS) on ventricular function, collagen synthesis, and the local renin-angiotensin system in rats. Male Wistar rats were randomized into control (C), steroid (S; nandrolone decanoate; 5 mg/kg sc, 2x/wk), steroid + losartan (SL; 20 mg.kg(-1).day(-1)), trained (T), trained + steroid (T+S), and trained + steroid + losartan (T+SL; n = 14/group) groups. Swimming was performed 5 times/wk for 10 wk. Serum testosterone increased in S and T+S. Resting heart rate was lower in T and T+S. Percent change in left ventricular (LV) weight-to-body weight ratio increased in S, T, and T+S. LV systolic pressure declined in S and T+S. LV contractility increased in T (P < 0.05). LV relaxation increased in T (P < 0.05). It was significantly lower in T+S compared with C. Collagen volumetric fraction (CVF) and hydroxyproline were higher in S and T+S than in C and T (P < 0.05), and the CVF and LV hypertrophy were prevented by losartan treatment. LV-ANG I-converting enzyme activity increased (28%) in the S group (33%), and type III collagen synthesis increased (56%) in T+S but not in T group. A positive correlation existed between LV-ANG I-converting enzyme activity and collagen type III expression (r(2) = 0.88; P < 0.05, for all groups). The ANG II and angiotensin type 1a receptor expression increased in the S and T+S groups but not in T group. Supraphysiological doses of AS exacerbated the cardiac hypertrophy in exercise-trained rats. Exercise training associated with AS induces maladaptive remodeling and further deterioration in cardiac performance. Exercise training associated with AS causes loss of the beneficial effects in LV function induced by exercising. These results suggest that aerobic exercise plus AS increases cardiac collagen content associated with activation of the local renin-angiotensin system.

The effect of chronic exogenous androgen on myocardial function following acute ischemia-reperfusion in hosts with different baseline levels of sex steroids

BACKGROUND

Gender differences exist in the myocardial response to acute ischemia/reperfusion (I/R) injury and may be attributed to the effects of the sex hormones estrogen and testosterone. The role of estrogen in myocardial injury has been extensively studied but little information exists regarding the myocardial involvement of testosterone. Based on the deleterious effects of chronic endogenous and acute testosterone exposure observed in our previous studies, we postulated that chronic exogenous testosterone administration would also exhibit deleterious effects on myocardial function following I/R.

METHODS

Langendorff perfused rat hearts were subjected to 25 min ischemia, 40 min reperfusion, and left ventricular developed pressure (LVDP) was recorded. Control and 5alpha-dihydrotestosterone (DHT) treated groups each consisted of normal males, castrated males, ovariectomized (OVX) females, and senescent females. P < 0.05 = significant.

RESULTS

Chronic DHT replacement therapy showed no difference in functional ischemic recovery as measured by LVDP after 40 min reperfusion in castrated males (65.1 +/- 8.13% versus 66.3 +/- 4.54%), OVX females (64.5 +/- 10.6% versus 50.2 +/- 5.97%), and senescent females (42.1 +/- 0.04% versus 41 +/- 0.05%). Interestingly, LVDP was greater in DHT treated males than control males after I/R (65.2 +/- 8.20% versus 47.6 +/- 5.19%). Also, DHT treatment resulted in significantly increased recovery of LVDP after only 10 min reperfusion in castrated males, OVX females, and senescent females compared with their untreated counterparts (54.8 +/- 11.9% versus 32.9 +/- 5.75%, 66.7 +/- 11.5% versus 43.1 +/- 8.15%, 53.4 +/- 10.1% versus 32.9 +/- 5.75%, respectively).

CONCLUSION

Contrary to the adverse effects we observed in earlier studies with both endogenous and brief exogenous testosterone in myocardium injured by I/R, the present study revealed that chronic exogenous testosterone neither improved nor worsened myocardial functional recovery following 25 min ischemia and 40 min reperfusion.

[Nandrolone administration does not promote hypertrophy of soleus muscle in rats]

Anabolic androgenic steroids (AAS) are compounds formed from testosterone or one of its derivatives, which are largely used by amateur e professional athletes to improve the athletic performance. However, the scientific information about the relation between the use of AAS and muscle hypertrophy is controversial. The aim of this study was to evaluate the effects of testosterone and physical training on muscle hypertrophy. Male Wistar rats received i.m. injections of Deca-Durabolin or vehicle during 6 weeks. Trained rats were submitted to a resistance physical training, by jumping up and down in water carrying an overload. Sedentary and trained animals were anesthetized and sacrificed. Soleus muscle was removed for the quantification of total protein and DNA concentration. In the end of the treatment, body weight of trained animals treated with vehicle or AAS was lower than the body weight of respective sedentary. Total protein concentration and the ratio muscle weight/body weight of all experimental groups were not altered. Trained group treated with AAS presented lower DNA concentration than trained group treated with vehicle. The administration of nandrolone decanoate did not promote hypertrophy on soleus muscle, not even when the use of AAS was associated to resistance physical training.

Brief exposure to exogenous testosterone increases death signaling and adversely affects myocardial function after ischemia

Chronic endogenous testosterone exposure adversely affects proinflammatory and proapoptotic signaling after ischemia/reperfusion; however, it remains unknown whether a single acute testosterone exposure is equally detrimental. We hypothesized that acute exogenous testosterone infusion before ischemia would worsen myocardial functional recovery, increase the activation of MAPKs and caspase-3, and increase myocardial proinflammatory cytokine production. To study this, isolated-perfused rat hearts (Langendorff) from adult females and castrated males were subjected to 25-min ischemia and 40-min reperfusion with and without acute testosterone infusion (17beta-hydroxy-4-androstenone, 10 ng x ml(-1) x min(-1)) before ischemia. Myocardial contractile function was continuously recorded. After ischemia/reperfusion, hearts were assessed for levels of testosterone (ELISA), expression of proinflammatory cytokines (ELISA), and activation of MAPKs and caspase-3 (Western blot analysis). Data were analyzed with two-way ANOVA or Student's t-test; P < 0.05 was statistically significant. All indices of postischemic functional recovery were decreased with acute exogenous testosterone compared with the untreated groups. Acute testosterone infusion increased activation of MAPKs and caspase-3 following ischemia/reperfusion. However, there were no significant differences in the myocardial proinflammatory cytokine production after brief testosterone infusion. A single acute exposure to exogenous testosterone before ischemia worsens myocardial functional recovery and increases activation of MAPKs and caspase-3. These findings confirm the deleterious effects of testosterone on myocardium, elucidate the nongenomic mechanistic pathways of testosterone, and may have important clinical implications for patients who have acute exposure to exogenous testosterone.

Sex dimorphism in cardiac pathophysiology: experimental findings, hormonal mechanisms, and molecular mechanisms

The higher cardiovascular risk in men and post-menopausal women implies a protective action of estrogen. A large number of experimental studies have provided strong support to this concept. However, the recent clinical trials with negative outcomes regarding hormone replacement therapy call for "post hoc" reassessment of existing information, models, and research strategies as well as a summary of recent findings. Sex steroid hormones, in particular estrogen, regulate numerous processes that are related to the development and progression of cardiovascular disease through a variety of signaling pathways. Use of genetically modified models has resulted in interesting information on diverse actions mediated by steroid receptors. By focusing on experimental findings, we have reviewed hormonal, cellular, and signaling mechanisms responsible for sex dimorphism and actions of hormone replacement therapy and addressed current limitations and future directions of experimental research.

Dilated cardiomyopathy and acute liver injury associated with combined use of ephedra, gamma-hydroxybutyrate, and anabolic steroids

Anabolic-androgenic steroids are synthetic derivatives of testosterone that some athletes have used to enhance muscle mass and improve their athletic performance. Ephedrine is a potent sympathomimetic agent that can lead to cardiomyopathy similar to that seen with catecholamine excess. Adverse cardiovascular events attributed to anabolic steroid and ephedra use, such as arrhythmias, myocardial infarction, cardiomyopathy, and sudden death, are rarely reported. Bodybuilders have used gamma-hydroxybutyrate, a potent secretagogue of growth hormone, to promote muscle development. Although dilated cardiomyopathy is a known complication of excess growth hormone levels, it has not been associated with use of gamma-hydroxybutyrate. A healthy 40-year-old man was admitted to our hospital for new-onset congestive heart failure and severe acute hepatitis that developed several months after he began using anabolic-androgenic steroids, ephedra, and gamma-hydroxybutyrate supplements. Analysis with an objective causality assessment scale revealed a probable adverse drug reaction between the patient's use of anabolic steroids, ephedra, and gamma-hydroxybutyrate and the development of his cardiomyopathy and acute liver injury.

SEX DIFFERENCES IN THE MYOCARDIAL INFLAMMATORY RESPONSE TO ACUTE INJURY

Hemorrhage, trauma, ischemia/reperfusion, burn, and sepsis each lead to cardiac dysfunction. These insults lead to an inflammatory cascade, which plays an important role in this process. Gender has been shown to influence the inflammatory response, as well as outcomes after acute injury. The mechanisms by which gender affects the inflammatory response to and the outcome of acute injury are being actively investigated. We searched PubMed for articles in the English language by using the search words sex, gender, estrogen, testosterone, inflammation, acute injury, ischemia reperfusion, sepsis, trauma, and burns. These were used in various combinations. We read the abstracts of the relevant titles to confirm their relevance, and the full articles were then extracted. References from extracted articles were checked for any additional relevant articles. This review will examine evidence for gender differences in the outcome to acute injury, explain the myocardial inflammatory response to acute injury, and elucidate the various mechanisms by which gender affects the myocardial response to acute injury.

Role of endogenous testosterone in myocardial proinflammatory and proapoptotic signaling after acute ischemia-reperfusion

Myocardial ischemia is the leading cause of death in both men and women; however, very little information exists regarding the effect of testosterone on the response of myocardium to acute ischemic injury. We hypothesized that testosterone may exert deleterious effects on myocardial inflammatory cytokine production, p38 MAPK activation, apoptotic signaling, and myocardial functional recovery after acute ischemia-reperfusion (I/R). To study this, isolated, perfused rat hearts (Langendorff) from adult males, castrated males, and males treated with a testosterone receptor blocker (flutamide) were subjected to 25 min of ischemia followed by 40 min of reperfusion. Myocardial contractile function (left ventricular developed pressure, left ventricular end-diastolic pressure, positive and negative first derivative of pressure) was continuously recorded. After reperfusion, hearts were analyzed for expression of tissue TNF-α, IL-1β, and IL-6 (ELISA) and activation of p38 MAPK, caspase-1, caspase-3, caspase-11, and Bcl-2 (Western blot). All indices of postischemic myocardial functional recovery were significantly higher in castrated males or flutamide-treated males compared with untreated males. After I/R, castrated male and flutamide-treated male hearts had decreased TNF-α, IL-1β, and IL-6; decreased activated p38 MAPK; decreased caspase-1, caspase-3, and caspase-11; and increased Bcl-2 expression compared with untreated males. These results show that blocking the testosterone receptor (flutamide) or depleting testosterone (castration) in normal males improves myocardial function after I/R. These effects may be attributed to the proinflammatory and/or the proapoptotic properties of endogenous testosterone. Further understanding may allow therapeutic manipulation of sex hormone signaling mechanisms in the treatment of acute I/R.

Effects of exercise and steroid on skeletal muscle apoptosis in themdx mouse

Reports concerning the influence of exercise loading and steroid administration on dystrophinopathy are inconsistent. To investigate the effect of muscle exercise in Duchenne muscular dystrophy (DMD), 15 control and 15 mdx mice, an animal model of DMD, were divided into free-living (n = 6), exercise (n = 6), and immobilization (n = 3) groups. Free-living and exercise groups were further divided into steroid-treated and sham-treated groups to evaluate the effect of steroid administration. We measured apoptotic changes by in situ DNA nick-end labeling (TUNEL), DNA fragmentation assay, and Western blotting for Bcl-2 and BAX. Apoptosis was most prominent in the sham-treated exercise group, and it was significantly reduced in the steroid-treated exercise group. The steroid-treated free-living group showed a higher rate of apoptotic change than the sham-treated free-living group. Apoptosis was minimized in the free-living condition, whereas exercise loading and immobilization caused apoptotic change in this muscular dystrophy animal model. Steroid administration induced apoptosis in muscle of free-living mice, but alleviated the apoptotic damage caused by exercise loading in mdx mice. These findings suggest that steroid administration may be effective in preventing a postexercise deterioration of skeletal muscle in animal models of DMD.

Estrogen and testosterone have opposing effects on chronic cardiac remodeling and function in mice with myocardial infarction

Premenopausal women are much less prone to develop cardiovascular disease than men of similar age, but this advantage no longer applies after menopause. We previously found that male mice have a significantly higher rate of cardiac rupture than females during the acute phase of myocardial infarction (MI); however, the effects of sexual hormones on chronic remodeling are unknown. We hypothesized that estrogen (E) may protect the heart from chronic remodeling and deterioration of function post-MI, whereas testosterone (T) may have adverse effects. Mice (4 wk old) of both genders were divided into four groups: female groups consisted of 1) sham ovariectomy (S-Ovx) + placebo (P) (S-Ovx + P), 2) S-Ovx + T, 3) Ovx + P, and 4) Ovx + T; and male groups consisted of 1) sham castration (S-Cas)+ P (S-Cas + P), 2) S-Cas + 17beta-estradiol (E), 3) Cas + P, and 4) Cas + E. MI was induced 6 wk later. Echocardiography was performed to assess cardiac function and left ventricular dimensions (LVD). Myocyte cross-sectional area (MCSA) was measured at the end of the study. In females, both testosterone and ovariectomy decreased ejection fraction (EF) and increased LVD, and when combined they aggravated cardiac function and remodeling further. Testosterone significantly increased MCSA. In males, castration or estrogen increased EF and reduced LVD, whereas castration significantly reduced MCSA. Our data suggest that estrogen prevents deterioration of cardiac function and remodeling after MI, but testosterone worsens cardiac dysfunction and remodeling and has a pronounced effect when estrogen levels are reduced.

Pathophysiologic role of myocardial apoptosis in post-infarction left ventricular remodeling

Left ventricular (LV) remodeling and heart failure (HF) complicate acute myocardial infarction (AMI) even weeks to months after the initial insult. Apoptosis may represent an important pathophysiologic mechanism causing progressive myocardiocyte loss and LV dilatation even late after AMI. This review will discuss the role of apoptosis according to findings in animal experimental data and observational studies in humans in order to assess clinical relevance, determinants, and mechanisms of myocardial apoptosis and potential therapeutic implications. More complete definition of the impact of myocardiocyte loss on prognosis and of the mechanisms involved may lead to improved understanding of cardiac remodeling and possibly improved patients' care. Mitochondrial damage and bcl-2 to bax balance play a central role in ischemia-dependent apoptosis while angiotensin II and beta(1)-adrenergic-stimulation may be major causes of receptor-mediated apoptosis. Benefits due to treatment with ACE-inhibitors and beta-blockers appear to be in part due to reduced myocardial apoptosis. Moreover, infarct-related artery patency late after AMI may be a major determinant of myocardial apoptosis and clinical benefits deriving from an open artery late post AMI (the "open artery hypothesis") may be, at least in part, due to reduced myocardiocyte loss.

Anabolic steroid abuse and dependence

Anabolic-androgenic steroids (AAS) are mainly used to treat androgen deficiency syndromes and, more recently, catabolic states such as AIDS-associated wasting. There is no evidence in the reviewed literature that AAS abuse or dependence develops from the therapeutic use of AAS. Conversely, 165 instances of AAS dependence have been reported among weightlifters and bodybuilders who, as part of their weight training regimens, chronically administered supraphysiologic doses, often including combinations of injected and oral AAS as well as other drugs of abuse. A new model is proposed in which both the "myoactive" and psychoactive effects of AAS contribute to the development of AAS dependence. The adverse consequences of AAS are reviewed, as well as their assessment by means of a history and physical, mental status examination, and laboratory testing. When patients with AAS use disorders are compared with patients with other substance use disorders, both similarities and differences become apparent and have implications for treatment.