Influence Testosterone Levels Research Articles

METFORMIN REDUCES TESTOSTERONE LEVEL IN TYPE 2 DIABETES MELLITUS PATIENTS AND ITS THERAPY BY TRADITIONAL MEDICINE

BackgroundType 2 Diabetes Mellitus (T2DM) is a chronic metabolic disorder characterized by insulin resistance and hyperglycemia. Metformin, a commonly prescribed treatment for T2DM, is known for its effectiveness in improving glycemic control. Recent studies suggest that metformin may also influence testosterone levels in male patients, a hormone crucial for male reproductive health, muscle mass maintenance, and overall quality of life.Medicinal plants were traditionally used for influencing the testosterone level in the body which may be given as a therapy for the side – effects of metformin tablet. ObjectiveTo assess the impact of metformin treatment on testosterone levels in male patients with Type 2 Diabetes Mellitus compared to non-diabetic males, and to evaluate the potential traditional medical treatment methods consequences of reduced testosterone levels. MethodsThis projection is a prospective observational study conducted among 60 patients total divided into 30 males taking metformin as a hyperglycaemic agent with Type 2 Diabetes Mellitus and 30 males without any diabetic treatment will be carried out in different out-patient department of Shri MahantIndiresh Hospital, Patel Nagar, Dehradun to assess the level of testosterone in Type 2 Diabetes Mellitus taking metformin and in Non-Diabetic treatment. And based on this, more methods of traditional medicines for reducing testosterone levels were summarized. ResultsIt was demonstrated that the type 2 diabetes mellitus male patients who are being treated with metformin are associated with significantly reduction in testosterone serum levels when compared to non-diabetic patients.Several plants were examinedand clinically studies were performed on them. It was discovered that these plants have been effective in increasing the testosterone level, which may be given as a therapy to help the patients. ConclusionIn aspects of this study shows reduction in the testosterone levels which may lead to low sex drives and induction of low testosterone induced erectile dysfunction. Metformin is used to treat T2DM along with-it, it decreases testosterone levels which impacts on the lifestyle of patients. So, there is essential need to further study the effect of metformin on testosterone levels in patients with T2DM. Additionally, plants that may be useful in increasing the testosterone levels should be studied further for their beneficial characteristics and potential therapeutic applications.

Life history and environment predict variation in testosterone across vertebrates.

Endocrine systems act as key intermediaries between organisms and their environments. This interaction leads to high variability in hormone levels, but we know little about the ecological factors that influence this variation within and across major vertebrate groups. We study this topic by assessing how various social and environmental dynamics influence testosterone levels across the entire vertebrate tree of life. Our analyses show that breeding season length and mating system are the strongest predictors of average testosterone concentrations, whereas breeding season length, environmental temperature, and variability in precipitation are the strongest predictors of within-population variation in testosterone. Principles from small-scale comparative studies that stress the importance of mating opportunity and competition on the evolution of species differences in testosterone levels, therefore, likely apply to the entire vertebrate lineage. Meanwhile, climatic factors associated with rainfall and ambient temperature appear to influence variability in plasma testosterone, within a given species. These results, therefore, reveal how unique suites of ecological factors differentially explain scales of variation in circulating testosterone across mammals, birds, reptiles, amphibians, and fishes.

A Review of foods and food supplements increasing testosterone levels

Androgens are essential for male physical activity. Age-related androgen deficiency, known as late-onset hypogonadism (LOH), is considered a risk factor for several diseases. There are many men's health supplements on the market. Therefore, the purpose of this review is to summarize the food ingredients that have been suggested in published literature to increase testosterone levels. A review of previously reported animal studies suggested that 5 representative nutritional components, 7 food ingredients, and 25 supplements were associated with testosterone. Some food and supplements influence testosterone levels in various animals by directly increasing testosterone or suppressing the decrease in testosterone production due to testicular toxicity. There are three mechanisms by which foods or supplements increase testosterone production: 1) regulating luteinizing hormone, the hormone that stimulates testosterone production, 2) regulating testosterone synthase in the testis, and 3) regulating testosterone-degrading enzymes. In contrast, suppressing the decrease in testosterone depends on the antioxidant effect of the foods. Although detailed mechanistic studies and clinical trials are required to validate these findings, the use of food to regulate testosterone levels is a promising therapeutic option.

Effect of Testosterone Synthesis and Conversion on Serum Testosterone Levels in Obese Men.

Obesity is associated with decreased testosterone levels in males. Testosterone is synthesized by testosterone synthetic enzymes, which are stimulated by luteinizing hormone (LH). Testosterone can also be converted to estradiol via the aromatase. The objective of this study was to examine the factors related to testosterone synthesis and conversion, and to systematically evaluate the key processes that influence testosterone levels in male obesity. Three hundred and two male subjects (aged 25-45 years old) were divided according to BMI into normal weight (18.5-23.9 kg/m2), overweight (24-27.9 kg/m2), and obese (≥28 kg/m2) groups; or divided following WHR into non-abdominal obesity and abdominal obesity groups (WHR: ≥0.9). Male C57BL/6 mice were divided into normal diet (ND) and high-fat diet (HFD)-induced obesity group. Serum sex hormones and aromatase levels were measured using ELISAs. Testosterone synthetic enzymes in the testes were measured by qRT-PCR. The testosterone levels in obese men and abdominal obesity men were lower than normal men. In abdominal obesity men serum LH levels were decreased and associated with testosterone levels after multivariate regression analysis. Serum aromatase levels were increased in abdominal obesity males. In mice, compared to the ND group, the HFD group had decreased steroidogenic acute regulatory protein (StAR). However, aromatase levels in subcutaneous adipose tissue were higher in the ND group than HFD group. In conclusion, according to this study decreased testicular synthesis function and the conversion of testosterone may explain the reduction in testosterone levels in male obesity, and the decrease of testicular synthesis may change first.

Does Exogenous Testosterone Modulate Men’s Ratings of Facial Dominance or Trustworthiness?

Previous research indicates that men’s testosterone levels, or personality and contextual variables known to influence testosterone levels, predict men’s attributions of social and personality characteristics from faces. However, the correlational nature of many of these past findings precludes our ability to establish causal pathways. Here, across two pharmacological challenge experiments, we examined the extent to which testosterone reduced men’s perceptions of trustworthiness from emotionally-neutral faces (Experiment 1, N = 30, within-subjects design) or sensitivity to dominance from men’s faces that varied in characteristically dominant shape (Experiment 2, N = 117, between-subjects design). Results from Experiment 1 showed that administration of testosterone did not significantly lower men’s perceptions of trustworthiness. An unexpected order effect (i.e., drug x order of administration interaction) showed that trustworthiness ratings were higher after testosterone, but only if men received testosterone on the first day and placebo on the second day; importantly, this effect was directionally opposite to that reported in the literature and to that predicted for the present study. Experiment 2 demonstrated that dominance perceptions did not vary as a function of whether men received testosterone or placebo. Supplementary analyses with linear mixed effects generally support the main findings across experiments, but also provide more nuanced details involving exploratory individual difference variables. Results from the present experiments provide important information to a growing body of research examining testosterone and complex social processes, and may help inform future research on the topic.

Circulating testosterone and feather-gene expression of receptors and metabolic enzymes in relation to melanin-based colouration in the barn owl

Knowledge of how and why secondary sexual characters are associated with sex hormones is important to understand their signalling function. Such a link can occur if i) testosterone participates in the elaboration of sex-traits, ii) the display of an ornament triggers behavioural response in conspecifics that induce a rise in testosterone, or iii) genes implicated in the elaboration of a sex-trait pleiotropically regulate testosterone physiology. To evaluate the origin of the co-variation between melanism and testosterone, we measured this hormone and the expression of enzymes involved in its metabolism in feathers of barn owl (Tyto alba) nestlings at the time of melanogenesis and in adults outside the period of melanogenesis. Male nestlings displaying smaller black feather spots had higher levels of circulating testosterone, potentially suggesting that testosterone could block the production of eumelanin pigments, or that genes involved in the production of small spots pleiotropically regulate testosterone production. In contrast, the enzyme 5α-reductase, that metabolizes testosterone to DHT, was more expressed in feathers of reddish-brown than light-reddish nestlings. This is consistent with the hypothesis that testosterone might be involved in the expression of reddish-brown pheomelanic pigments. In breeding adults, male barn owls displaying smaller black spots had higher levels of circulating testosterone, whereas in females the opposite result was detected during the rearing period, but not during incubation. The observed sex- and age-specific co-variations between black spottiness and testosterone in nestling and adult barn owls may not result from testosterone-dependent melanogenesis, but from melanogenic genes pleiotropically regulating testosterone, or from colour-specific life history strategies that influence testosterone levels.

Relationships of Polychlorinated Biphenyls and Dichlorodiphenyldichloroethylene ( p,p’ -DDE) with Testosterone Levels in Adolescent Males

Background: Concern persists over endocrine-disrupting effects of persistent organic pollutants (POPs) on human growth and sexual maturation. Potential effects of toxicant exposures on testosterone levels during puberty are not well characterized.Objectives: In this study we evaluated the relationship between toxicants [polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (p,p´-DDE), hexachlorobenzene (HCB), and lead] and testosterone levels among 127 Akwesasne Mohawk males 10 to < 17 years of age with documented toxicant exposures.Methods: Data were collected between February 1996 and January 2000. Fasting blood specimens were collected before breakfast by trained Akwesasne Mohawk staff. Multivariable regression models were used to estimates associations between toxicants and serum testosterone, adjusted for other toxicants, Tanner stage, and potential confounders.Results: The sum of 16 PCB congeners (Σ16PCBs) that were detected in ≥ 50% of the population was significantly and negatively associated with serum testosterone levels, such that a 10% change in exposure was associated with a 5.6% decrease in testosterone (95% CI: –10.8, –0.5%). Of the 16 congeners, the more persistent ones (Σ8PerPCBs) were related to testosterone, whereas the less persistent ones, possibly reflecting more recent exposure, were not. When PCB congeners were subgrouped, the association was significant for the sum of eight more persistent PCBs (5.7% decrease; 95% CI: –11, –0.4%), and stronger than the sum of six less persistent congeners (3.1% decrease; 95% CI: –7.2, 0.9%). p,p´-DDE was positively but not significantly associated with serum testosterone (5.2% increase with a 10% increase in exposure; 95% CI: –0.5, 10.9%). Neither lead nor HCB was significantly associated with testosterone levels.Conclusions: Exposure to PCBs, particularly the more highly persistent congeners, may negatively influence testosterone levels among adolescent males. The positive relationship between p,p´-DDE and testosterone indicates that not all POPs act similarly.Citation: Schell LM, Gallo MV, Deane GD, Nelder KR, DeCaprio AP, Jacobs A; Akwesasne Task Force on the Environment. 2014. Relationships of polychlorinated biphenyls and dichlorodiphenyldichloroethylene (p,p´-DDE) with testosterone levels in adolescent males. Environ Health Perspect 122:304–309; http://dx.doi.org/10.1289/ehp.1205984

Depressive Symptoms in Men Aged 50 Years and Older and Their Relationship to Genetic Androgen Receptor Polymorphism and Sex Hormone Levels in Three Different Samples

Depression in aging men has been related to low sex hormone concentrations; the putatively modulating effects of the genetically determined androgen receptor (AR) cytosine-adenosine-guanine (CAG) repeat polymorphism are often not taken into account. The aim of this study was to determine how sex hormone levels and the AR polymorphism relate to depressive symptoms in aging men. This cross-sectional study of men aged 50 years and older included 120 consecutive patients of the Department of Psychosomatics and Psychotherapy, 76 consecutive patients of the Andrologic Clinic, and 100 participants from the community sample (CS); all participants completed the Patient Health Questionnaire. Morning blood samples were analyzed for total and free testosterone, estradiol, and the AR CAG polymorphism. Patients on hormone substitution or other medication known to influence testosterone levels were excluded. The two clinical samples had significantly longer AR CAG repeats and higher depression levels compared with the CS. When controlling for possible confounders, depression scores were positively correlated with CAGn (r = 0.20, df: 107, p ≤ 0.038) in psychosomatic patients and with CAGn (r = 0.27, df: 55, p ≤ 0.043) and estradiol (r = 0.31, df: 55, p ≤ 0.019) in andrologic patients, whereas the CS showed no significant correlations between depression scores, CAGn, and sex hormones. CAGn did not correlate significantly with testosterone in the three samples. Regression analysis confirmed association of CAGn with depression. Conclusions from these data must be considered to be preliminary and need to be replicated. However, our results point to associations between the genetic AR polymorphism and vulnerability to depressive symptomatology.

Abstract B118: Modifiable correlates of low testosterone in U.S. men

Abstract Background: In some studies, men with low total, free, or SHBG-adjusted testosterone possibly had a higher risk of cancer death. Because testosterone replacement therapy for men with clinically low testosterone has an uncertain risk versus benefit ratio, identifying modifiable factors that influence testosterone level and that are public health targets is needed. Obesity (lower testosterone) and cigarette smoking (higher testosterone) are two behavioral factors that are recognized to influence testosterone levels; given the great magnitude of the adverse effects of cigarette smoking, it is not a prevention strategy. Thus, in this study we investigated obesity as well as dietary and lifestyle factors in association with low total and free testosterone. Methods: The Third National Health and Nutrition Examination Survey (NHANES III), conducted 1988–1994, was a cross-sectional study of the U.S. civilian non-institutionalized population. Subjects participated in an interview, underwent a physical examination, and provided a blood specimen. Serum was available for 1470 men who participated in the morning session of Phase I (1988–1991) and were ≥20 years old. Testosterone and sex hormone binding globulin (SHBG) were measured by competitive electrochemiluminescence immunoassay. Free testosterone was estimated by mass action. We excluded men whose testosterone level was ≤2nd percentile because these men may have had congenital hypogonadism. We defined low total and free testosterone as ≤ 3.0 ng/mL and ≤ 0.07 ng/mL, respectively. We estimated the associations of the modifiable factors with low total and free testosterone using logistic regression adjusting for age and race/ethnicity. Results: Measures of overall and central adiposity were positively associated with low total and free testosterone. After mutual adjustment, men with high waist circumference (ethnic specific cutpoints; vs. low) were 2.59 (95% CI: 1.12–6.00) times more likely to have low total testosterone and 2.65 (95% CI: 1.44–4.89) times more likely to have low free testosterone, whereas body mass index and percent body fat did not remain statistically significantly associated. Independent of waist circumference, percent of calories from protein, fruit and vegetable intake, alcoholic beverage consumption, and physical activity were not statistically significantly associated with low total and free testosterone. These results were similar in men who did not have comorbidities at time of blood draw and in non-smokers. Discussion: Cross-sectionally, high waist circumference was the most consistent correlate of low total and free testosterone. These findings suggest that avoiding or reducing central adiposity may be one way to prevent clinically low androgen levels. Given that men with low androgens may have a higher risk of cancer death, our results may have import for cancer prevention and/or survival. Citation Information: Cancer Prev Res 2010;3(1 Suppl):B118.

Cambios en las hormonas sexuales en varones mayores de 50 años. Prevalencia de niveles bajos de testosterona y factores de riesgo

ObjectivesTo investigate the changes in sexual hormones in a selected male population older than 50 years of age. To assess the frequency of biochemical hypogonadism and which factors are related to testosterone levels Patients and methodsA Cross-sectional study was carried out on 230 Spanish men older than 50 years of age. Blood tests were performed including: total testosterone, SHBG, calculated free testosterone, dehidroepiandrosterone sulfate, androstendione, estradiol, bioavailable estradiol, FSH, LH, and prolactin. Clinical and socio-demographic backgrounds were investigated. The frequency of biochemical hypogonadism was established using total and free testosterone levels as diagnostic criteria. Factors that may influence testosterone levels were evaluated by univariate and multivariate statistical analysis, and a logistic regression model was used to determine which factors can predict biochemical hypogonadism according to free testosterone levels ResultsAge was associated with a significant decrease (p<0.05) in total testosterone (0.6% per year), free testosterone (1.3% per year), dehidroepiandrosterone sulfate (1.8% per year) and bioavailable estradiol (0.69% per year). Moreover, an increase in SHBG, LH, and FSH was observed (p<0.05). According to total testosterone levels, 4.8% of the men were hypogonadal, whereas 24.8% were hypogonadal when free testosterone was considered. In the univariate analysis, obesity, diabetes mellitus and hyperlipemia were related to lower total testosterone levels, while free testosterone levels were lower in men with sedentary life, lower levels of education, obesity or diabetes mellitus. In the multivariate analysis age, diabetes mellitus and obesity were inversely related to total and free testosterone levels. Free testosterone was also inversely related to hyperlipemia. For biochemical hypogonadism, simple logistic regression analysis selected age, sedentary life, obesity and diabetes mellitus. In the multivariate analysis age, obesity and diabetes mellitus had significant independent prognostic value ConclusionsStarting from 50 years of age, a significant age-related decrease in total testosterone, free testosterone, dehidroepiandrosterone sulfate and bioavailable estradiol is observed. The frequency of biochemical hypogonadism is higher when free testosterone levels are used for diagnosis. Total testosterone levels were related to age, diabetes mellitus and obesity. Free testosterone was related to age, diabetes mellitus, obesity and hyperlipemia. The probability of suffering low free testosterone levels increases with age, diabetes mellitus and/or obesity

Testosterone levels in men with erectile dysfunction

To investigate the frequency of hypogonadism in men with erectile dysfunction (ED) and to assess which factors are related with low testosterone levels. In all, 165 men with ED were assessed; the evaluation included: hormonal profiles, serum total and free testosterone (using Vermeulen's formula) levels, and self-reported questionnaires on erectile function and desire domains of the International Index of Erectile Function. The frequency of hypogonadism was established using total and free testosterone levels as diagnostic criteria. The factors that might influence testosterone levels were evaluated by univariate and multivariate statistical analysis, and a logistic regression was used to determine which factors can predict free testosterone levels below normal limits (biochemical hypogonadism). Using the total testosterone levels, 4.8% of the men were hypogonadal, whereas when using the free testosterone levels, 17.6% were hypogonadal. In the univariate analyses, not smoking and hypertension were associated with lower total and free testosterone levels. Ageing, absence of nocturnal erections and a lower erectile function score were only associated with lower free testosterone serum levels. There was no association between total and free testosterone levels and desire. In the multivariate analysis, only total testosterone levels were related to hypertension, while free testosterone levels were related to age and nocturnal erections. For biochemical hypogonadism, simple logistic regression analysis selected age, erectile function score and aetiological diagnosis of ED as predictors. In the multivariate analysis only the erectile function score had significant independent prognostic value. The frequency of hypogonadism is higher when free testosterone levels are used for diagnosis. The total and free testosterone levels were not related to the level of sexual desire in men with ED. The free testosterone levels could be related to the quality and frequency of nocturnal erections, and when ED is more severe, it is more probable that free testosterone levels are below the 'normal' limit.