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Journal of the International Society of... Feb 2021Supplementing with creatine is very popular amongst athletes and exercising individuals for improving muscle mass, performance and recovery. Accumulating evidence also... (Review)
Review
Supplementing with creatine is very popular amongst athletes and exercising individuals for improving muscle mass, performance and recovery. Accumulating evidence also suggests that creatine supplementation produces a variety of beneficial effects in older and patient populations. Furthermore, evidence-based research shows that creatine supplementation is relatively well tolerated, especially at recommended dosages (i.e. 3-5 g/day or 0.1 g/kg of body mass/day). Although there are over 500 peer-refereed publications involving creatine supplementation, it is somewhat surprising that questions regarding the efficacy and safety of creatine still remain. These include, but are not limited to: 1. Does creatine lead to water retention? 2. Is creatine an anabolic steroid? 3. Does creatine cause kidney damage/renal dysfunction? 4. Does creatine cause hair loss / baldness? 5. Does creatine lead to dehydration and muscle cramping? 6. Is creatine harmful for children and adolescents? 7. Does creatine increase fat mass? 8. Is a creatine 'loading-phase' required? 9. Is creatine beneficial for older adults? 10. Is creatine only useful for resistance / power type activities? 11. Is creatine only effective for males? 12. Are other forms of creatine similar or superior to monohydrate and is creatine stable in solutions/beverages? To answer these questions, an internationally renowned team of research experts was formed to perform an evidence-based scientific evaluation of the literature regarding creatine supplementation.
Topics: Adiposity; Adolescent; Adult; Alopecia; Body Water; Child; Creatine; Dehydration; Dietary Supplements; Female; Humans; Kidney; Kidney Diseases; Male; Muscle Cramp; Muscle, Skeletal; Sex Factors; Sports Nutritional Physiological Phenomena; Testosterone; Testosterone Congeners
PubMed: 33557850
DOI: 10.1186/s12970-021-00412-w -
Frontiers in Endocrinology 2022Anabolic-androgenic steroids (AAS) are a class of hormones that are widely abused for their muscle-building and strength-increasing properties in high, nontherapeutic,... (Review)
Review
Anabolic-androgenic steroids (AAS) are a class of hormones that are widely abused for their muscle-building and strength-increasing properties in high, nontherapeutic, dosages. This review provides an up-to-date and comprehensive overview on how these hormones work and what side effects they might elicit. We discuss how AAS are absorbed into the circulation after intramuscular injection or oral ingestion and how they are subsequently transported to the tissues, where they will move into the extravascular compartment and diffuse into their target cells. Inside these cells, AAS can biotransform into different metabolites or bind to their cognate receptor: the androgen receptor. AAS and their metabolites can cause side effects such as acne vulgaris, hypertension, hepatotoxicity, dyslipidemia, testosterone deficiency, erectile dysfunction, gynecomastia, and cardiomyopathy. Where applicable, we mention treatment options and self-medication practices of AAS users to counteract these side effects. Clinicians may use this review as a guide for understanding how AAS use can impact health and to assist in patient education and, in some cases, the management of side effects.
Topics: Male; Humans; Anabolic Androgenic Steroids; Anabolic Agents; Testosterone Congeners; Erectile Dysfunction; Steroids
PubMed: 36644692
DOI: 10.3389/fendo.2022.1059473 -
Revista Clinica Espanola Dec 2022The use of anabolic steroids affects not only professional athletes but also the general population (bodybuilders, gym clients, and adolescents). In the first case, its... (Review)
Review
The use of anabolic steroids affects not only professional athletes but also the general population (bodybuilders, gym clients, and adolescents). In the first case, its use is prohibited and sanctioned by the World Anti-Doping Agency and Olympic committees. For the other users, it is difficult to establish its prevalence since many obtain the products via the internet. The reasons for its use are varied and different forms of use and other types of users have been described. Among the side effects of steroid use, hypogonadism is the most frequent cause for endocrinological consultation. After a general introduction to doping, this review describes the historical background of anabolic-androgenic steroids, their classification, forms of use, physiological effects, adverse effects on different organs and systems, treatment of hypogonadism, as well as detection methods.
Topics: Adolescent; Humans; Anabolic Agents; Anabolic Androgenic Steroids; Testosterone Congeners; Sports; Athletes; Hypogonadism
PubMed: 36400345
DOI: 10.1016/j.rceng.2022.09.003 -
The Journal of Cell Biology Jul 2018Insulin is the paramount anabolic hormone, promoting carbon energy deposition in the body. Its synthesis, quality control, delivery, and action are exquisitely regulated... (Review)
Review
Insulin is the paramount anabolic hormone, promoting carbon energy deposition in the body. Its synthesis, quality control, delivery, and action are exquisitely regulated by highly orchestrated intracellular mechanisms in different organs or "stations" of its bodily journey. In this review, we focus on these five stages of the journey of insulin through the body and the captivating cell biology that underlies the interaction of insulin with each organ. We first analyze insulin's biosynthesis in and export from the β-cells of the pancreas. Next, we focus on its first pass and partial clearance in the liver with its temporality and periodicity linked to secretion. Continuing the journey, we briefly describe insulin's action on the blood vasculature and its still-debated mechanisms of exit from the capillary beds. Once in the parenchymal interstitium of muscle and adipose tissue, insulin promotes glucose uptake into myofibers and adipocytes, and we elaborate on the intricate signaling and vesicle traffic mechanisms that underlie this fundamental function. Finally, we touch upon the renal degradation of insulin to end its action. Cellular discernment of insulin's availability and action should prove critical to understanding its pivotal physiological functions and how their failure leads to diabetes.
Topics: Adipocytes; Adipose Tissue; Diabetes Mellitus; Glucose; Humans; Insulin; Insulin Resistance; Insulin-Secreting Cells; Muscle, Skeletal; Testosterone Congeners
PubMed: 29622564
DOI: 10.1083/jcb.201802095 -
Dermatology Online Journal Aug 2020Multiple prescription medications may cause or aggravate acne. A number of dietary supplements have also been linked to acne, including those containing vitamins B6/B12,... (Review)
Review
Multiple prescription medications may cause or aggravate acne. A number of dietary supplements have also been linked to acne, including those containing vitamins B6/B12, iodine, and whey, as well as "muscle building supplements" that may be contaminated with anabolic-androgenic steroids (AAS). Acne linked to dietary supplements generally resolves following supplement discontinuation. Lesions associated with high-dose vitamin B6 and B12 supplements have been described as monomorphic and although pathogenesis is unknown, a number of hypotheses have been proposed. Iodine-related acne may be related to the use of kelp supplements and has been reported as monomorphic, inflammatory pustules on the face and upper trunk. Whey protein supplements, derived from milk and used for bodybuilding, are associated with papulonodular acne involving the trunk and sometimes the face. Finally, AAS-induced acne has been described as acne fulminans, acne conglobata, and acne papulopustulosa. With studies indicating that about half of US adults report using dietary supplements, it is important that dermatologists directly ask acne patients about their supplement use and educate them on the potential risks of even seemingly innocuous dietary supplements.
Topics: Acne Vulgaris; Dietary Supplements; Female; Humans; Iodine; Male; Testosterone Congeners; Vitamin B 12; Vitamin B 6; Vitamin B Complex; Whey Proteins
PubMed: 32941710
DOI: No ID Found -
International Journal of Sport... Mar 2001Exercise has a profound effect on muscle growth, which can occur only if muscle protein synthesis exceeds muscle protein breakdown; there must be a positive muscle... (Review)
Review
Exercise has a profound effect on muscle growth, which can occur only if muscle protein synthesis exceeds muscle protein breakdown; there must be a positive muscle protein balance. Resistance exercise improves muscle protein balance, but, in the absence of food intake, the balance remains negative (i.e., catabolic). The response of muscle protein metabolism to a resistance exercise bout lasts for 24-48 hours; thus, the interaction between protein metabolism and any meals consumed in this period will determine the impact of the diet on muscle hypertrophy. Amino acid availability is an important regulator of muscle protein metabolism. The interaction of postexercise metabolic processes and increased amino acid availability maximizes the stimulation of muscle protein synthesis and results in even greater muscle anabolism than when dietary amino acids are not present. Hormones, especially insulin and testosterone, have important roles as regulators of muscle protein synthesis and muscle hypertrophy. Following exercise, insulin has only a permissive role on muscle protein synthesis, but it appears to inhibit the increase in muscle protein breakdown. Ingestion of only small amounts of amino acids, combined with carbohydrates, can transiently increase muscle protein anabolism, but it has yet to be determined if these transient responses translate into an appreciable increase in muscle mass over a prolonged training period.
Topics: Amino Acids; Dietary Carbohydrates; Energy Intake; Energy Metabolism; Exercise; Humans; Insulin; Muscle Development; Muscle Proteins; Muscle, Skeletal; Testosterone
PubMed: 11255140
DOI: 10.1123/ijsnem.11.1.109 -
Fertility and Sterility Apr 2002To describe the sources, production rates, circulating concentrations, and regulatory mechanisms of the major androgen precursors and androgens in women. (Review)
Review
OBJECTIVE
To describe the sources, production rates, circulating concentrations, and regulatory mechanisms of the major androgen precursors and androgens in women.
DESIGN
Review of the major published literature.
RESULT(S)
Quantitatively, women secrete greater amounts of androgen than of estrogen. The major circulating steroids generally classified as androgens include dehydroepiandrosterone sulphate (DHEAS), dehydroepiandrosterone (DHEA), androstenedione (A), testosterone (T), and dihydrotestosterone in descending order of serum concentration, though only the latter two bind the androgen receptor. The other three steroids are better considered as pro-androgens. Dehydroepiandrosterone is primarily an adrenal product, regulated by adrenocorticotropic hormone (ACTH) and acting as a precursor for the peripheral synthesis of more potent androgens. Dehydroepiandrosterone is produced by both the ovary and adrenal, as well as being derived from circulating DHEAS. Androstenedione and testosterone are products of the ovary and the adrenal. Testosterone circulates both in its free form, and bound to protein including albumin and sex steroid hormone-binding globulin (SHBG), the levels of which are an important determinant of free testosterone concentration.
CONCLUSION(S)
The postmenopausal ovary is an androgen-secreting organ and the levels of testosterone are not directly influenced by the menopausal transition or the occurrence of menopause. Dihydrotestosterone (DHT) is primarily a peripheral product of testosterone metabolism. Severe androgen deficiency occurs in hypopituitarism, but other causes may lead to androgen deficiency, including Addison's disease, corticosteroid therapy, chronic illness, estrogen replacement (leads to elevated SHBG and, therefore, low free testosterone), premenopausal ovarian failure, or oophorectomy.
Topics: Androgens; Androstenedione; Dehydroepiandrosterone; Dehydroepiandrosterone Sulfate; Dihydrotestosterone; Female; Humans; Ovary; Sex Hormone-Binding Globulin; Testosterone
PubMed: 12007895
DOI: 10.1016/s0015-0282(02)02985-0 -
Chinese Medical Journal Sep 2019Anabolic-androgenic steroids (AAS) represents a group of synthetic testosterone derivatives that play an important role in clinical treatment. These drugs are widely... (Review)
Review
OBJECTIVE
Anabolic-androgenic steroids (AAS) represents a group of synthetic testosterone derivatives that play an important role in clinical treatment. These drugs are widely abused among the general public to increase lean weight and improve athletic performance. It has been reported that AAS use can produce many adverse effects, especially the occurrence of cardiovascular risk. Although there are many related studies, there has been no consensus on AAS use and cardiovascular risk. The present study was to review the effect of AAS on the cardiovascular system.
DATA SOURCES
The data in this review were obtained from articles included in PubMed and the National Center for Biotechnology Information database.
STUDY SELECTION
Original articles, case reports, and systematic reviews about AAS were selected for the article.
RESULTS
The use/abuse of AAS is correlated with higher cardiovascular risks, and many AAS users/abusers had cardiovascular diseases. However, there are many confounding factors in the studies that explored the causality between AAS intake and disease development, and additional studies are required to determine AAS toxicity.
CONCLUSION
AAS produces toxic effects on the cardiovascular system, and it is necessary to ensure that more people know this about AAS, including medical personnel.
Topics: Atherosclerosis; Cardiovascular Diseases; Cardiovascular System; Female; Humans; Hypertension; Male; Risk Factors; Testosterone Congeners; Thromboembolism
PubMed: 31478927
DOI: 10.1097/CM9.0000000000000407 -
Medicina (Kaunas, Lithuania) Nov 2020Anabolic-androgenic steroids (AASs) are a group of synthetic molecules derived from testosterone and its related precursors. AASs are widely used illicitly by... (Review)
Review
Anabolic-androgenic steroids (AASs) are a group of synthetic molecules derived from testosterone and its related precursors. AASs are widely used illicitly by adolescents and athletes, especially by bodybuilders, both for aesthetic uses and as performance enhancers to increase muscle growth and lean body mass. When used illicitly they can damage health and cause disorders affecting several functions. Sudden cardiac death (SCD) is the most common medical cause of death in athletes. SCD in athletes has also been associated with the use of performance-enhancing drugs. This review aimed to focus on deaths related to AAS abuse to investigate the cardiac pathophysiological mechanism that underlies this type of death, which still needs to be fully investigated. This review was conducted using PubMed Central and Google Scholar databases, until 21 July 2020, using the following key terms: "((Sudden cardiac death) OR (Sudden death)) AND ((androgenic anabolic steroid) OR (androgenic anabolic steroids) OR (anabolic-androgenic steroids) OR (anabolic-androgenic steroid))". Thirteen articles met the inclusion and exclusion criteria, for a total of 33 reported cases. Of the 33 cases, 31 (93.9%) were males while only 2 (61%) were females. Mean age was 29.79 and, among sportsmen, the most represented sports activity was bodybuilding. In all cases there was a history of AAS abuse or a physical phenotype suggesting AAS use; the total usage period was unspecified in most cases. In 24 cases the results of the toxicological analysis were reported. The most detected AASs were nandrolone, testosterone, and stanozolol. The most frequently reported macroscopic alterations were cardiomegaly and left ventricular hypertrophy, while the histological alterations were foci of fibrosis and necrosis of the myocardial tissue. Four principal mechanisms responsible for SCD have been proposed in AAS abusers: the atherogenic model, the thrombosis model, the model of vasospasm induced by the release of nitric oxide, and the direct myocardial injury model. Hypertrophy, fibrosis, and necrosis represent a substrate for arrhythmias, especially when combined with exercise. Indeed, AAS use has been shown to change physiological cardiac remodeling of athletes to pathophysiological cardiac hypertrophy with an increased risk of life-threatening arrhythmias.
Topics: Adolescent; Adult; Anabolic Agents; Athletes; Death, Sudden, Cardiac; Female; Humans; Male; Testosterone; Testosterone Congeners
PubMed: 33158202
DOI: 10.3390/medicina56110587 -
Hormones and Behavior Jan 2012Testosterone and other anabolic-androgenic steroids enhance athletic performance in men and women. As a result, exogenous androgen is banned from most competitive... (Review)
Review
Testosterone and other anabolic-androgenic steroids enhance athletic performance in men and women. As a result, exogenous androgen is banned from most competitive sports. However, due to variability in endogenous secretion, and similarities with exogenous testosterone, it has been challenging to establish allowable limits for testosterone in competition. Endogenous androgen production is dynamically regulated by both exercise and winning in competition. Furthermore, testosterone may promote athletic performance, not only through its long-term anabolic actions, but also through rapid effects on behavior. In women, excess production of endogenous testosterone due to inborn disorders of sexual development (DSD) may convey a competitive advantage. For many years, female competitors have been subject to tests of sexual genotype and phenotype known as gender verification. Although gender verification has not identified any normal man competing as a woman, this process has identified women athletes with DSD. As understanding of DSD has expanded in recent years, women with DSD are increasingly able to continue athletic competition.
Topics: Anabolic Agents; Athletic Performance; Doping in Sports; Epitestosterone; Female; Humans; Male; Sex Chromosome Aberrations; Sex Determination Analysis; Sex Differentiation; Testosterone
PubMed: 21983229
DOI: 10.1016/j.yhbeh.2011.09.010