testosterone Tag

Mohamed Kabbaj, PHD Professor of Biomedical Sciences & Neurosciences College of Medicine Florida State UniversityMedicalResearch.com Interview with: Mohamed Kabbaj, PHD Professor of Biomedical Sciences & Neurosciences College of Medicine Florida State University Medical Research: What is the background for this study? What are the main findings? Dr. Kabbaj: While anxiety and depressive disorders a major public health concern worldwide, so too are the pervasive sex differences that exist within these pathologies. Fluctuations in the predominant female reproductive hormones, estradiol and progesterone, are thought to be a major contributor to the higher prevalence of anxiety and depression in women compared to men. However, many studies in humans and rodents alike have demonstrated that testosterone, the primary male sex hormone, also influences affective status and may yield protective benefits against the development of mood-related disturbances. Indeed, hypogonadal males with low testosterone levels experience increased rates of anxiety and depressive symptoms. In many of these cases, testosterone replacement alone or in addition to antidepressant medication have been shown to effectively improve mood. How this hormone acts in the brain to exert its beneficial effects, however, is much less clear. Interestingly, it is well-known that many of testosterone’s effects in the brain occur via its conversion to estrogen by the enzyme aromatase. What remained unclear was whether or not this conversion to estrogen was critical for testosterone’s protective anxiolytic and antidepressant effects—so Nicole Carrier and Samantha Saland from Dr. Kabbaj’s lab aimed to figure out just that. To do this, Carrier and Saland targeted an area of the hippocampus in the brain involved in mood regulation where testosterone is known to act to carry out some of its anxiolytic and antidepressant effects in male rats. Here, they inhibited the enzyme responsible for the conversion of testosterone into estrogen and investigated performance in mood-related behaviors. In doing so, they discovered that testosterone’s anxiolytic- and antidepressant-like effects were lost unless this hormone was first converted into estrogen. Importantly, they also found that continuous testosterone and estrogen treatments had very similar effects on the expression of genes within this brain region that are highly implicated in the regulation of mood as well as antidepressant treatments.

Abraham Morgentaler, MD Director and Founder Men’s Health BostonMedicalResearch.com Interview with: Abraham Morgentaler, MD Director and Founder Men’s Health Boston Medical Research: What is the background for this study? What are the main findings? Response: There has been  tremendous media attention over the last 15 months to two retrospective studies that reported increased cardiovascular risks with testosterone. Those reports anchored a variety of stories critical of testosterone therapy for non-scientific reasons, such as alleged dangers of direct-to-consumer advertising.  In this review we investigated the two recent studies in depth, as well as the broader literature regarding testosterone and cardiovascular issues. One primary finding was that the studies alleging risk were remarkably weak and flawed- one reported low rates of MI and had no control group, and the other had such large data errors (nearly 10% of the all-male population turned out to be female!) that 29 medical societies have called for its retraction. In contrast, there is substantial literature suggesting that testosterone therapy, or naturally occurring higher levels of testosterone, is protective against atherosclerosis, and mortality.  Several small randomized controlled trials in men with known heart disease- angina and congestive heart failure- have even shown benefits for men that received testosterone compared with placebo.

Maarten C. Bosland, DVSc, PhD Professor of Pathology Department of Pathology, College of Medicine University of Illinois at Chicago Chicago, IL 60612MedicalResearch.com Interview with:  Maarten C. Bosland, DVSc, PhD Professor of Pathology Department of Pathology, College of Medicine University of Illinois at Chicago Chicago, IL 60612 Medical Research: What are the main findings of the study? Dr. Bosland: The two main findings are : (1) that long-term, low-dose testosterone treatment induces prostate cancer in rats (none occurred in control rats) and increases the number of rats with malignant tumors at any site in the body compared to control rats, and (2) that in rats treated long-term with testosterone after a single prostate-targeted chemical carcinogen treatment a high incidence of prostate cancer is induced, even at a very low testosterone dose.

Jacques Baillargeon, PhD Director, Epidemiology Division Associate Professor Department of Preventive Medicine and Community Health University of Texas Medical Branch MedicalResearch.com Interview with: Jacques Baillargeon, PhD Director, Epidemiology Division Associate Professor Department of Preventive Medicine and Community Health University of Texas Medical Branch MedicalResearch: What are the main findings of the study? Dr. Baillargeon: The main findings of the study were that older men who were treated with testosterone did not appear to have an increased risk of Myocardial Infarction.  For men with high MI risk, testosterone use appeared to be modestly protective against MI.

Dr. Farid Saad Global Medical Affairs Men’s Healthcare, Bayer Pharma, Berlin, Germany; Gulf Medical University School of Medicine Ajman, United Arab Emirates;MedicalResearch.com Interview with: Dr. Farid Saad Global Medical Affairs Men’s Healthcare, Bayer Pharma, Berlin, Germany; Gulf Medical University School of Medicine Ajman, United Arab Emirates MedicalResearch: What are the main findings of the study? Dr. Saad: There are two ongoing registry studies in men with testosterone deficiency (hypogonadism, defined by two separate measures of low serum testosterone and the presence of symptoms which are typical for testosterone deficiency). The studies are being conducted by office urologists. The total number of men who have been treated for a maximum duration of six years is 561, mean age just under 60 years. All men received three-monthly intra-muscular injections of a long-acting testosterone depot preparation. The main findings were that at baseline only five per cent of these men had normal weight, some 25 per cent were overweight and the majority obese. Both overweight and obese men showed reductions in weight and waist circumference. The more obese men were, the more they lost. Men in the highest obesity category grade III (BMI ≥ 40 kg/m2), had a mean weight loss of 26 kg and a reduction of waist size by 12 cm. In parallel, all components of the metabolic syndrome improved in a clinically meaningful magnitude, i.e., blood pressure, lipid profile, and glycemic control. When we analyzed a subgroup of 156 men with type 2 diabetes, we found marked improvements in their diabetes as a result of adding testosterone to the standard diabetes treatment men are receiving by their famaily physicians.

Robert S. Tan MD, MBA, AGSFMedicalresearch.com Interview with: Robert S. Tan MD, MBA, AGSF Clinical Director & Chief Geriatrics, Michael DeBakey VAMC Director, Opal Medical, LLC Clinical Professor of Family & Community Medicine, UTHSC-Houston Associate Professor of Medicine (Geriatrics), Baylor College Medicine Medicalresearch: What are the main findings of the study? Dr. Tan: Our findings¹ are similar to that of an early study by Shores et al ² and other studies on endogenous testosterone that found testosterone lowered mortality. In the analysis of 39,937 patients at the Low T Centers up to 5 years, the rate ratios of new MI and strokes on testosterone as compared to general community based data sets (3,4) was 0.12 (C.I. 0.08-0.18, p<0.0001) and 0.05 (C.I 0.02-0.13, p<0.0001) respectively. Thus, there appears to be a lower risk of heart attacks and strokes with patients on testosterone. While the compared population sets are not identical or real controls; our study does suggest that rates of MI and strokes in real life practice with testosterone treated patients are even lower than the general population registries (which may include older patients).

dr_san_franciscoMedicalResearch.com Interview with: Dr. Ignacio F. San Francisco Departamento de Urología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile MedicalResearch: What are the main findings of the study? Answer: Increasingly, men with low-risk prostate cancer are undergoing a close monitoring regimen called active surveillance, instead of moving forward immediately with treatment. However it is still unclear which men will develop evidence for worsening or more aggressive disease during active surveillance. In this study of 154 men with Gleason 6 prostate cancer followed for 38 months, we found that low levels of free testosterone were significantly associated with increased risk of developing more aggressive disease. We found no significant association with total testosterone concentrations, although there was a general trend towards increased risk with lower levels.

J. Bradley Layton, PhD Postdoctoral Research Associate University of North Carolina at Chapel HillMedicalResearch.com Interview with: J. Bradley Layton, PhD Postdoctoral Research Associate University of North Carolina at Chapel Hill MedicalResearch.com: What are the main findings of the study? Dr. Layton: Use of testosterone testing and treatment had greatly increased over the past decade, with more pronounced increases seen in the United States than in the United Kingdom. The increases in testing in the UK seem to be targeted, identifying more men with reduced testosterone levels, but the increases in the US seem to be identifying more and more men with normal levels. Many of the men who begin testosterone treatment in the US appear to have normal testosterone levels to begin with.

MedicalResearch.com Interview with: Bledar Daka MD, PhD-student. University of Gothenburg in Sweden MedicalResearch.com: What are the main findings of your study? Answer: The main finding of our study was that low testosterone levels were associated with MI in both men and women but the association was stronger in men with type 2 diabetes. This finding was in concert with findings that could associate the CVD death with low levels of testosterone especially in elder men.

Dr Bu Beng Yeap   MBBS, FRACP, PhD Professor, School of Medicine and Pharmacology, University of Western Australia Endocrinologist, Department of Endocrinology and Diabetes, Fremantle Hospital. School of Medicine and Pharmacology
Level 2, T Block, Fremantle Hospital, Alma Street, Fremantle, Western Australia 6160, AustraliaMedicalResearch.com Interview with: Dr Bu Beng Yeap   MBBS, FRACP, PhD Professor, School of Medicine and Pharmacology, University of Western Australia Endocrinologist, Department of Endocrinology and Diabetes, Fremantle Hospital. MedicalResearch.com: What are the main findings of the study? Answer: We found that older men with testosterone levels in the middle of the range had the lowest mortality risk. Having a low testosterone level predicted higher mortality, and there was no benefit of having a high-normal testosterone level. Men with optimal rather than high testosterone levels lived longest. The other important finding was that men with higher dihydrotestosterone levels had lower mortality from ischaemic heart disease, suggesting that androgens may protect against heart disease in older men.

MedicalResearch.com eInterview with Andrew Weickhardt, MBBS, DMedSc, FRACP MedicalResearch.com: What are the main findings of the study? Dr. Weickhardt: The study was hoping to confirm our earlier published observation that crizotinib use led to low testosterone in male patients. The earlier study was based on our observation of symptoms of low testosterone in some patients treated with the drug, and had suggested strongly that crizotinib led to rapid decrease in testosterone levels, however this was based only on a single center's patients, and only 19 patients. We hoped to do this by surveying a larger population of crizotinib treated patients across multiple institutions. We serially measured several relevant hormones.