Development of selective androgen receptor modulators (SARMs)

New selective androgen receptor modulator TEI-SARM2 improves muscle function in a Duchenne muscular dystrophy rat model

Duchenne muscular dystrophy (DMD) is a severe muscle wasting disease caused by a genetic mutation in the Dmd gene. Dystrophin mutant mice (mdx) have traditionally been used for DMD research as a disease model in the preclinical stage; however, mdx mice exhibit only very mild phenotypes to partially mimic muscle degeneration and regeneration. To overcome this limitation in preclinical studies, DMD mutant rats (DMD rats) generated by CRISPR/Cas were used as a DMD model to exhibit age-dependent progressive muscle degeneration and pathophysiological features similar to DMD patients and more severe than those displayed by mdx mice. TEI-SARM2 is a non-steroidal, orally available selective androgen receptor modulator (SARM) developed as a pharmaceutical candidate for the treatment of muscle wasting diseases based on its potent anabolic activity on skeletal muscle mass. In this study, long-term treatment of daily oral administration of TEI-SARM2 to DMD rats significantly improved muscle function (endurance and strength) assessed by grip and tetanic force measurements. TEI-SARM2 did not increase the muscle weight of hindlimbs in male DMD rats; moreover, long-term, weekly oral administration for 24 weeks improved muscle function with reduced side effects on the prostate and testes weight. Histological analysis showed that TEI-SARM2 significantly reduced adipose tissue infiltration in DMD muscle. In female DMD rats, both daily and weekly TEI-SARM2 treatment showed anabolic effects and enhanced muscle strength and endurance. Taken together, these results indicate that TEI-SARM2 has non-anabolic and anabolic effects that improve dystrophic muscle dysfunction and can be a supportive therapeutic option for DMD.

Curcumin administration alleviates seminal vesicle damage in type 1 diabetic rats by promoting AQP8 expression through AR activation

Diabetes is a detriment to male reproductive health, notably through its capacity to diminish secretion from accessory glands such as the seminal vesicles and prostate, which are crucial for reproductive function. Curcumin, a naturally derived polyphenol renowned for its anti-inflammatory and antioxidative attributes, has demonstrated potential in mitigating tissue damage across various organs in diabetic patients. Despite its established benefits, the specific impact of curcumin on seminal vesicle damage in the context of diabetes remains underexplored. This investigation delves into the therapeutic potential of curcumin in ameliorating seminal vesicle damage in diabetic rats, thereby elucidating its underlying mechanisms. This study focused on twenty male SD rats divided into two distinct groups, a control cohort and a diabetic contingent, and employed a streptozocin (STZ)-induced type 1 diabetic rat model to ascertain seminal vesicle alterations secondary to diabetes. Ultrasonography was used to measure rat seminal vesicle sizes for comparison with postdissection measurements. This study revealed that (1) seminal vesicle volume and seminal fluid secretion were reduced in diabetic rats and (2) ultrasonography can predict seminal vesicle secretory dysfunction in diabetic rats, providing a theoretical basis for selecting animal models of diabetic seminal vesicle dysfunction for subsequent studies. Thirty male SD rats were subsequently divided into three groups: control, diabetic, and curcumin-treated. The curcumin group, which was subjected to a one-month-long intervention after STZ-induced diabetes onset, exhibited significant histological and functional recovery. Haematoxylin‒eosin (HE) staining revealed disordered seminal vesicle tissue structures and decreased epithelial cell height in diabetic rats, which was partially restored after curcumin treatment. Western blot and PCR results demonstrated that the expression levels of androgen receptor (AR) and aquaporin (AQP)8 in the seminal vesicle tissues of diabetic rats were decreased, whereas curcumin treatment led to increases in the expression levels of AR and AQP8. Seminal vesicle cells were cultured in vitro and divided into six groups: control, HG, HG-CUR-5 µM, HG-CUR-10 µM, HG-CUR-20 µM, and HG-CUR-50 µM. After 48 h of intervention, the fructose concentration in the culture medium was measured, and the expression of AR and AQP8 in the control, HG, and HG-CUR-20 µM groups was determined via Western blotting and PCR. The results revealed that the expression of AR and APQ8 in high glucose-treated seminal vesicle cells was decreased and that curcumin treatment upregulated the expression of AR and AQP8. After the addition of bicalutamide (an AR inhibitor), the expression of AQP8 was reduced. These findings suggest that curcumin may alleviate seminal vesicle damage in type 1 diabetic rats by activating the AR-AQP8 pathway.

Athlete Selective Androgen Receptor Modulators Abuse: A Systematic Review

BACKGROUND

Selective androgen receptor modulators (SARMs) are small-molecule compounds that exert agonist and antagonist effects on androgen receptors in a tissue-specific fashion. Because of their performance-enhancing implications, SARMs are increasingly abused by athletes. To date, SARMs have no Food and Drug Administration approved use, and recent case reports associate the use of SARMs with deleterious effects such as drug-induced liver injury, myocarditis, and tendon rupture.

PURPOSE

(1) To provide a comprehensive synthesis of the literature pertaining to SARMs from a sports medicine perspective and (2) to provide a better understanding of the clinical effects, treatment protocols, prevalence, and potential contamination associated with athlete-consumed SARMs.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A systematic review of the English-language literature from PubMed, Cochrane, and Embase databases was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Articles relevant to SARM clinical outcomes, elimination profiles, contamination, safety profiles, prevalence, and doping control were included.

RESULTS

A total of 72 articles from 2003 to 2022 were identified for inclusion. The prevalence of SARM use among athletes is estimated to be 1% to 3%. SARM preclinical and clinical studies reported significant increases in lean body mass and side effects-including bone remodeling, testosterone suppression, and kidney, liver, and prostate enlargement. Thirteen case reports described 15 cases of SARM abuse. All described patients were men, with a median age of 32 years (range, 19-52 years), more than half were identified as athletes (8/15), and all ingested SARMs orally for a mean course of 8 weeks. Five patients described in the case reports explicitly denied "illicit drug use," implying patients may believe their use to be legal. Athletes most commonly purchased SARMs online, and most of these compounds have been shown to be contaminated with other substances, contributing to adverse effects. Athletes reported consuming SARMs at much higher doses than clinically studied, which may increase the risk of the reported side effects, such as liver injury, impaired insulin sensitivity, cardiovascular events, and tendon damage.

CONCLUSION

The results of this systematic review serve to educate sports medicine clinicians and researchers on how to better identify, diagnose, and treat athlete SARM abuse. SARM use is associated with increased muscle mass, hepatotoxicity, cardiotoxicity, tendon damage, and androgenic side effects throughout the body-including prostate enlargement and serum testosterone suppression. Identifying and treating SARM abuse requires taking a thorough substance and supplement use history with open communication, providing literature-supported patient education, negotiating SARM discontinuation, and performing multidisciplinary treatment of adverse events. Athlete SARM abuse is increasingly widespread and unsafe, and public health oversight bodies should advocate for regulation of these gray-market compounds.

Sarcopenia in MASLD-Eat to Beat Steatosis, Move to Prove Strength

The connections between sarcopenia and various chronic conditions, including type 2 diabetes (T2DM), metabolic syndrome (MetS), and liver disease have been highlighted recently. There is also a high occurrence of sarcopenia in metabolic dysfunction-associated steatotic liver disease (MASLD) patients, who are often disregarded. Both experimental and clinical findings suggest a complex, bidirectional relationship between MASLD and sarcopenia. While vitamin D, testosterone, and specific drug therapies show promise in mitigating sarcopenia, consensus on effective treatments is lacking. Recent focus on lifestyle interventions emphasizes dietary therapy and exercise for sarcopenic obesity in MASLD. Challenges arise as weight loss, a primary MASLD treatment, may lead to muscle mass reduction. The therapeutic approach to sarcopenia in morbidly obese MASLD patients also includes bariatric surgery (BS). BS induces weight loss and stabilizes metabolic imbalances, but its impact on sarcopenia is nuanced, underscoring the need for further research. Our aim is to provide a comprehensive review of the interplay between sarcopenia and MASLD and offer insight into the most recent therapeutic challenges and discoveries, as sarcopenia is often overlooked or unrecognized and poses significant challenges for managing these patients.

Application and progress of 3D tumor models in breast cancer

Due to its high heterogeneity and significant impact on women's health globally, breast cancer necessitates robust preclinical models to understand tumor biology and guide personalized treatment strategies. Three-dimensional (3D) in vitro tumor models hold immense promise in this regard. These tumor models not only mimic the spatial structure and growth environment of tumors in vivo, but also retain the pathological and genetic characteristics of solid tumors. This fidelity makes them powerful tools for accelerating advancements in fundamental research and translational medicine. The diversity, modularity, and efficacy of 3D tumor models are driving a biotechnological revolution. As these technologies become increasingly sophisticated, 3D tumor models are poised to become powerful weapons in the fight against breast cancer. This article expounds on the progress made in utilizing 3D tumor models for breast cancer research.

A novel treatment strategy targeting cellular pathways with natural products to alleviate sarcopenia

Sarcopenia is a condition marked by a significant reduction in muscle mass and strength, primarily due to the aging process, which critically impacts muscle protein dynamics, metabolic functions, and overall physical functionality. This condition leads to increased body fat and reduced daily activity, contributing to severe health issues and a lower quality of life among the elderly. Recognized in the ICD-10-CM only in 2016, sarcopenia lacks definitive treatment options despite its growing prevalence and substantial social and economic implications. Given the aging global population, addressing sarcopenia has become increasingly relevant and necessary. The primary causes include aging, cachexia, diabetes, and nutritional deficiencies, leading to imbalances in protein synthesis and degradation, mitochondrial dysfunction, and hormonal changes. Exercise remains the most effective intervention, but it is often impractical for individuals with limited mobility, and pharmacological options such as anabolic steroids and myostatin inhibitors are not FDA-approved and are still under investigation. This review is crucial as it examines the potential of natural products as a novel treatment strategy for sarcopenia, targeting multiple mechanisms involved in its pathogenesis. By exploring natural products' multi-targeted effects, this study aims to provide innovative and practical solutions for sarcopenia management. Therefore, this review indicates significant improvements in muscle mass and function with the use of specific natural compounds, suggesting promising alternatives for those unable to engage in regular physical activity.

A molecular switch from tumor suppressor to oncogene in ER+ve breast cancer: Role of androgen receptor, JAK-STAT, and lineage plasticity

Cancers develop resistance to inhibitors of oncogenes mainly due to target-centric mechanisms such as mutations and splicing. While inhibitors or antagonists force targets to unnatural conformation contributing to protein instability and resistance, activating tumor suppressors may maintain the protein in an agonistic conformation to elicit sustainable growth inhibition. Due to the lack of tumor suppressor agonists, this hypothesis and the mechanisms underlying resistance are not understood. In estrogen receptor (ER)-positive breast cancer (BC), androgen receptor (AR) is a druggable tumor suppressor offering a promising avenue for this investigation. Spatial genomics suggests that the molecular portrait of AR-expressing BC cells in tumor microenvironment corresponds to better overall patient survival, clinically confirming AR's role as a tumor suppressor. Ligand activation of AR in ER-positive BC xenografts reprograms cistromes, inhibits oncogenic pathways, and promotes cellular elasticity toward a more differentiated state. Sustained AR activation results in cistrome rearrangement toward transcription factor PROP paired-like homeobox 1, transformation of AR into oncogene, and activation of the Janus kinase/signal transducer (JAK/STAT) pathway, all culminating in lineage plasticity to an aggressive resistant subtype. While the molecular profile of AR agonist-sensitive tumors corresponds to better patient survival, the profile represented in the resistant phenotype corresponds to shorter survival. Inhibition of activated oncogenes in resistant tumors reduces growth and resensitizes them to AR agonists. These findings indicate that persistent activation of a context-dependent tumor suppressor may lead to resistance through lineage plasticity-driven tumor metamorphosis. Our work provides a framework to explore the above phenomenon across multiple cancer types and underscores the importance of factoring sensitization of tumor suppressor targets while developing agonist-like drugs.

The concept of Gallium-controlled double C-H functionalization of aliphatic CH2-groups driven by Vinyl carbocations

The direct C-H activation of inert C(sp3)-H bonds in a hydrocarbon chain has been a very attractive target in organic synthesis for many decades. Among all the variety of processes, those driven by vinyl carbocations are quite scarce thus far, and it is hard to control for unstabilized vinyl cations. In this study, we designed a double C(sp3)-H functionalization of unactivated alkyl CH2 groups to produce a totally substituted quaternary carbon stereocenter via insertion of vinyl carbocations. These processes represent complicated reaction cascades with high molecular complexity controlled by the cooperative action of Ga(III) salts & GaHal4- anions and allow one-step deep poly-functionalization of simple CH substrates to be performed. In practice, this concept was initially implemented with simple starting compounds such as alkyl acetylenes and activated cyclopropanes, alkenes, or cyclobutanes to construct norbornane, cyclopentatetralin, and other important skeletons.

Nuclear lamin A/C phosphorylation by loss of androgen receptor leads to cancer-associated fibroblast activation

Alterations in nuclear structure and function are hallmarks of cancer cells. Little is known about these changes in Cancer-Associated Fibroblasts (CAFs), crucial components of the tumor microenvironment. Loss of the androgen receptor (AR) in human dermal fibroblasts (HDFs), which triggers early steps of CAF activation, leads to nuclear membrane changes and micronuclei formation, independent of cellular senescence. Similar changes occur in established CAFs and are reversed by restoring AR activity. AR associates with nuclear lamin A/C, and its loss causes lamin A/C nucleoplasmic redistribution. AR serves as a bridge between lamin A/C and the protein phosphatase PPP1. Loss of AR decreases lamin-PPP1 association and increases lamin A/C phosphorylation at Ser 301, a characteristic of CAFs. Phosphorylated lamin A/C at Ser 301 binds to the regulatory region of CAF effector genes of the myofibroblast subtype. Expression of a lamin A/C Ser301 phosphomimetic mutant alone can transform normal fibroblasts into tumor-promoting CAFs.

Ambient ionization mass spectrometry provides screening of selective androgen receptor modulators

Ambient ionization mass spectrometry allows for analysis of samples in their natural state, i.e., with no sample pre-treatment. It can be viewed as a fast, simple, and economical analysis, but its main disadvantages include a lower analytical performance due to the presence of complex sample matrix and the lack of chromatographic separation prior to the introduction of the sample into the mass spectrometer. Here we present an application of two ambient ionization mass spectrometry techniques, i.e., Desorption Atmospheric Pressure Photoionization and Dielectric Barrier Discharge Ionization, for the analysis of known Selective Androgen Receptor Modulators, which represent common compounds of abuse in professional and semiprofessional sport. Eight real samples of illegal food supplements, seized by the local law enforcement, were used to test the performance of the ambient mass spectrometry and the results were validated against a newly developed targeted LC-UV-MS/MS method performed in multiple reaction monitoring mode with an external calibration for each analyte. In order to decide whether or not the compound can be declared as present, we proposed a system of rules for the interpretation of the obtained spectra. The criteria are based on mass spectrum matching (5-10 ppm accuracy from the theoretical exact mass and a correct isotopic pattern), duration of the mass signal (three or five consecutive scans, depending on the instrumentation used), and intensity above the background noise (threefold increase in intensity and absolute intensity above 5E4 or 1E5, depending on the instrumentation). When applying these criteria, good agreement was found between the tested methods. Ambient ionization techniques were effective at detecting SARMs at pharmacologically relevant doses, i.e., approximately above 1 mg per capsule, although they may fail to detect lower levels or isomeric species. It is demonstrated that when adhering to a set of clear and consistent rules, ambient mass spectrometry can be employed as a qualitative technique for the screening of illegal SARMs with sufficient confidence and without the necessity to perform a regular LC-MS analysis.

A comprehensive gas chromatography electron ionization high resolution mass spectrometry study of a new steroidal selective androgen receptor modulator (SARM) compound S42

The synthetic 20-keto-steroid S42 (1) demonstrated selective androgen receptor modulator (SARM) properties in preclinical studies and, consequently, received growing attention also in the context of sports drug testing programs. Fundamental understanding of the behavior of S42 (1) and of relevant derivatives in gas chromatography-electron ionization MS experiments at high resolution (GC-EI-HRMS) is indispensable to develop a reliable qualitative and quantitative doping control method for S42 (1) and its metabolites in body fluid matrices. We present important fundamental mechanistic data on the EI fragmentation behavior of S42 (1) and of silyl ether derivatives as well as of stable isotope-labelled reference material.

Detection of anabolic agents including selective androgen receptor modulators in samples outside of sport

Selective androgen receptor modulators (SARMs) are prohibited by the World Anti-Doping Agency (WADA) since 2008. Similarly, to anabolic androgenic steroids (AAS), SARMs are detrimental to health not only in athletes but also in the general population. However, studies of the occurrence of SARMs outside of sport are scarce. Swedish healthcare samples from the Drugs of Abuse Laboratory at Karolinska were analyzed using WADA-accredited screening methods at the Doping Control Laboratory in Stockholm to estimate the frequency of SARM use outside of the WADA laboratories. Twenty (4%) of the male urine samples (n = 542) were positive for SARMs, whereas none of the analyzed female samples (n = 100) contained any SARMs. The top three SARMs found were LGD-4033 followed by RAD140 and ostarine. Two or more SARMs were found in >50% of the SARM-positive samples. AASs were identified in 40% of samples containing SARMs. A difference between genders was observed where 34% male and 7% female samples contained AAS. Many samples displayed testosterone/epitestosterone values indicative of testosterone intake, without presence of other AAS, and hence, there is a risk that these samples are being falsely reported as negative. Our results indicate that SARM use might be a concern outside of sport. Subsequently, in addition to AAS, the healthcare system should also be informed about SARM abuse and the associated adverse side effects.

Selective Androgen Receptor Modulators Leading to Liver Injury: A Case Report

Selective androgen receptor modulators (SARMs) have gained popularity for their alleged ability to selectively target androgen receptors, potentially offering muscle-building benefits with fewer side effects than traditional steroids. However, the safety profile of SARMs, including RAD-140, is not fully understood. This case report presents a 29-year-old male who developed liver injury after taking RAD-140. The patient experienced jaundice and elevated liver enzymes after three months of RAD-140 use. A liver ultrasound revealed hepatic steatosis and a hyperechoic lesion. Symptoms resolved after discontinuing RAD-140. Similar cases of liver injury associated with RAD-140 have been reported, highlighting the potential hepatotoxicity of this SARM. Discontinuation of RAD-140 appears to reverse liver injury, but the long-term effects and risks of SARM use remain unclear. This case highlights the need for caution and monitoring when considering SARMs for performance enhancement.

Detection of the selective androgen receptor modulator S-23 and its metabolites in equine urine and plasma following oral administration

S-23 is an arylpropionamide selective androgen receptor modulator that has been investigated in animal models for use as a male hormonal contraceptive but is not yet available therapeutically. S-23 is available alongside other selective androgen receptor modulators (SARMs) to purchase online via uncontrolled sites, sold as supplement products. It has been detected in several human doping cases, highlighting the importance of identifying the best analytical targets for equine doping control. The purpose of this study was to investigate the detection of S-23 and its phase I metabolites in equine urine and plasma following a multiple dose oral administration to two Thoroughbred racehorses. Liquid chromatography-high resolution mass spectrometry was used for metabolite identification, and liquid chromatography-tandem mass spectrometry was used for full sample analysis and generation of urine and plasma profiles. S-23 and seven phase I metabolites were observed in urine following enzyme hydrolysis and solvolysis. The most abundant analyte detected was the hydroxylated 4-amino-2-(trifluoromethyl)benzonitrile metabolite, which also allowed the longest duration of detection in urine from both horses, for up to 360 h following administration. The data suggest that this metabolite was likely to be highly conjugated with both sulphate and glucuronide moieties. In plasma, S-23 and two phase I metabolites were observed. S-23 was the most abundant analyte detected for both horses, allowing detection for up to 143 h post-administration. To the best of the authors' knowledge, this is the first report of S-23 and metabolites in equine urine and plasma samples.

Liver Injury after Selective Androgen Receptor Modulator Intake: A Case Report and Review of the Literature

Liver injury associated with selective androgen receptor modulators (SARMs) is an issue that has not been reported often. We report a case of a previously healthy 24-year-old male, who was referred to our hospital for severe jaundice with intense pruritus. He had previously taken the SARM Enobosarm (also known as Ostarine) for muscle-building purposes. Blood serum levels of total bilirubin exceeded 30 mg/dL with only a slight elevation of liver enzymes. Liver biopsy revealed isolated hepatocellular cholestasis (bland cholestasis) with limited inflammation or necrosis. Supportive treatment was begun in our hospital with molecular adsorbent recirculation system (MARS) albumin dialysis, as well as cholestyramine for pruritus relief. During therapy, bilirubin levels and symptoms regressed, and after five sessions of dialysis, the patient could be released from our clinic in a markedly improved clinical and laboratory condition. However, bilirubin parameters regressed slowly after this, reaching normal levels as late as six months after first intake of the compound. Exome-based genetic testing brought about no pathogenic variants for cholestatic liver disease in our patient. Nevertheless, three common heterozygous polymorphisms associated with an increased risk for intrahepatic cholestasis could be identified. Our case demonstrates that SARMs can cause severe liver injuries not prominently mentioned in safety data sheets. Therefore, these compounds constitute a potential danger to the user's health. This holds especially true when taking SARMs without supervision by a medical professional, which should consist of a thorough monitoring of liver enzyme and bilirubin levels.

Frontiers in sarcopenia: Advancements in diagnostics, molecular mechanisms, and therapeutic strategies

The onset of sarcopenia is intimately linked with aging, posing significant implications not only for individual patient quality of life but also for the broader societal healthcare framework. Early and accurate identification of sarcopenia and a comprehensive understanding of its mechanistic underpinnings and therapeutic targets paramount to addressing this condition effectively. This review endeavors to present a cohesive overview of recent advancements in sarcopenia research and diagnosis. We initially delve into the contemporary diagnostic criteria, specifically referencing the European Working Group on Sarcopenia in Older People (EWGSOP) 2 and Asian Working Group on Sarcopenia (AWGS) 2019 benchmarks. Additionally, we elucidate comprehensive assessment techniques for muscle strength, quantity, and physical performance, highlighting tools such as grip strength, chair stand test, dual-energy X-ray Absorptiometry (DEXA), bioelectrical impedance analysis (BIA), gait speed, and short physical performance battery (SPPB), while also discussing their inherent advantages and limitations. Such diagnostic advancements pave the way for early identification and unequivocal diagnosis of sarcopenia. Proceeding further, we provide a deep-dive into sarcopenia's pathogenesis, offering a thorough examination of associated signaling pathways like the Myostatin, AMP-activated protein kinase (AMPK), insulin/IGF-1 Signaling (IIS), and the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathways. Each pathway's role in sarcopenia mediation is detailed, underscoring potential therapeutic target avenues. From a mechanistic perspective, the review also underscores the pivotal role of mitochondrial dysfunction in sarcopenia, emphasizing elements such as mitochondrial oxidative overload, mitochondrial biogenesis, and mitophagy, and highlighting their therapeutic significance. At last, we capture recent strides made in sarcopenia treatment, ranging from nutritional and exercise interventions to potential pharmacological and supplementation strategies. In sum, this review meticulously synthesizes the latest scientific developments in sarcopenia, aiming to enhance diagnostic precision in clinical practice and provide comprehensive insights into refined mechanistic targets and innovative therapeutic interventions, ultimately contributing to optimized patient care and advancements in the field.

From gains to gaps? How Selective Androgen Receptor Modulator (SARM) YK11 impact hippocampal function: In silico, in vivo, and ex vivo perspectives

Selective Androgen Receptor Modulators (SARMs), particularly (17α,20E)-17,20-[(1-methoxyethylidene)bis(oxy)]-3-oxo-19-norpregna-4,20-diene-21-carboxylic-acid-methyl-ester (YK11), are increasingly popular among athletes seeking enhanced performance. Serving as an Androgen Receptor (AR) agonist, YK11 stimulates muscle growth while inhibiting myostatin. Our study delved into the impact of YK11 on the rat hippocampus, analyzing potential alterations in neurochemical mechanisms and investigating its synergistic effects with exercise (EXE), based on the strong relationship between SARM users and regular exercise. Utilizing Physiologically Based Pharmacokinetic (PBPK) modeling, we demonstrated YK11 remarkable brain permeability, with molecular docking analysis revealing YK11 inhibitory effects on 5-alpha-reductase type II (5αR2), suggesting high cell bioavailability. Throughout a 5-week experiment, we divided the animals into the following groups: Control, YK11 (0.35 g/kg), EXE (swimming exercise), and EXE + YK11. Our findings showed that YK11 displayed a high binding affinity with AR in the hippocampus, influencing neurochemical function and modulating aversive memory consolidation, including the downregulation of the BDNF/TrkB/CREB signaling, irrespective of EXE combination. In the hippocampus, YK11 increased pro-inflammatory IL-1β and IL-6 cytokines, while reducing anti-inflammatory IL-10 levels. However, the EXE + YK11 group counteracted IL-6 effects and elevated IL-10. Analysis of apoptotic proteins revealed heightened p38 MAPK activity in response to YK11-induced inflammation, initiating the apoptotic cascade involving Bax/Bcl-2/cleaved caspase-3. Notably, the EXE + YK11 group mitigated alterations in Bcl-2 and cleaved caspase-3 proteins. In conclusion, our findings suggest that YK11, at anabolic doses, significantly alters hippocampal neurochemistry, leading to impairments in memory consolidation. This underscore concerns about the misuse risks of SARMs among athletes and challenges common perceptions of their minimal side effects.

Illegal products containing selective androgen receptor modulators purchased online from Italy: health risks for consumers

Background

Selective androgen receptor modulators (SARMs) are small synthetic drug molecules that are still not approved as medicine in Europe or the United States but are sold on illegal websites to improve sport performance, particularly bodybuilding.

Aim

To address the quality issues of illegal SARM products and their increasing diffusion in Italy with their potential health risks for consumers.

Methods

Web-based tools were used to investigate retail websites, trending searches, and information exchange via social media. Thirteen SARM products, purchased on retail websites accessible from Italy, were subject to visual inspection and chemical analysis by mass spectrometry and quantitative nuclear magnetic resonance.

Outcomes

The primary outcome was demonstration of additional health risks due to the illicit presence of other active ingredients, contamination, and misdosage in SARM products sold on the internet. The secondary outcome was to show the increasing trend of interest in Italy for these products.

Results

Most websites reported misleading information; specifically, the statement "for research only" was reported notwithstanding indications on dosage and training phases. The trending search showed that interest toward SARMs increased in Italy in the last years. The use of these products is clearly encouraged by the emerging phenomenon of "broscience" as revealed in socials. Visual inspection evidenced nonconform labeling. Qualitative analysis confirmed the presence of the stated SARM in about 70% of samples. In 23% of samples, the expected SARM was not detected but a different one instead, and in 1 sample, no SARMs were detected. Other undeclared pharmaceutical substances (tamoxifen, clomifene, testosterone, epimethandienone, tadalafil) were measured in 30% of samples. The copresence of >1 active substance was observed in >60% of samples. Quantitative nuclear magnetic resonance data showed nonuniform content ranging from 30% to 90% of the label claim.

Clinical Implications

The use of SARMs, in the presence of unexpected life-threatening reactions in persons using the products to increase sport performance, should be assessed.

Strengths and Limitations

This investigation involved an integrated approach to study SARM products and related sociologic aspects. The main shortcomings are the limited number of samples and retail websites in the clear web investigated.

Conclusion

SARMs sold online as food supplement-like products represent a health hazard due to the presence of unapproved and undeclared active substances. The presence of contaminants clearly indicates the absence of good manufacturing practices in the production, which increases the health risks.

Annual review of PROTAC degraders as anticancer agents in 2022

Following nearly two decades of development, significant advancements have been achieved in PROTAC technology. As of the end of 2022, more than 20 drugs have entered clinical trials, with ARV-471 targeting estrogen receptor (ER) showing remarkable progress by entering phase III clinical studies. In 2022, significant progress has been made on multiple targets. The first reversible covalent degrader designed to target the KRASG12C mutant protein, based on cyclopropionamide, has been reported. Additionally, the activity HDCA1 degrader surpassed submicromolar levels during the same year. A novel FEM1B covalent ligand called EN106 was also discovered, expanding the range of available ligands. Furthermore, the first PROTAC drug targeting SOS1 was reported. Additionally, the first-in-class degraders that specifically target BRD4 isoforms (BRD4 L and BRD4 S) have recently been reported, providing a valuable tool for further investigating the biological functions of these isoforms. Lastly, a breakthrough was also achieved with the first degrader targeting both CDK9 and Cyclin T1. In this review, we aimed to update the PROTAC degraders as potential anticancer agents covering articles published in 2022. The design strategies, degradation effects, and anticancer activities were highlighted, which might provide an updated sight to develop novel PROTAC degraders with great potential as anticancer agents as well as favorable drug-like properties.

Treatments Targeting the Androgen Receptor and Its Splice Variants in Breast Cancer

Breast cancer is a major cause of death worldwide. The complexity of endocrine regulation in breast cancer may allow the cancer cells to escape from a particular treatment and result in resistant and aggressive disease. These breast cancers usually have fewer treatment options. Targeted therapies for cancer patients may offer fewer adverse side effects because of specificity compared to conventional chemotherapy. Signaling pathways of nuclear receptors, such as the estrogen receptor (ER), have been intensively studied and used as therapeutic targets. Recently, the role of the androgen receptor (AR) in breast cancer is gaining greater attention as a therapeutic target and as a prognostic biomarker. The expression of constitutively active truncated AR splice variants in breast cancer is a possible mechanism contributing to treatment resistance. Therefore, targeting both the full-length AR and AR variants, either through the activation or suppression of AR function, depending on the status of the ER, progesterone receptor, or human epidermal growth factor receptor 2, may provide additional treatment options. Studies targeting AR in combination with other treatment strategies are ongoing in clinical trials. The determination of the status of nuclear receptors to classify and identify patient subgroups will facilitate optimized and targeted combination therapies.

Selective androgen receptor modulator use and related adverse events including drug-induced liver injury: Analysis of suspected cases

PURPOSE

Selective androgen receptor modulators (SARMs) have demonstrated agonist activity on the androgen receptor in various tissues, stimulating muscle mass growth and improving bone reconstruction. Despite being in clinical trials, none has been approved by the Food and Drug Administration (FDA) or European Medicines Agency for pharmacotherapy. Still, SARMs are very popular as performance-enhancing drugs. The FDA has issued warnings about the health risks associated with SARMs, but the long-term exposure and possible adverse events still need to be fully understood. This review aims to evaluate the adverse events associated with using SARMs by humans.

METHODS

PubMed database was searched from September 16, 2022, to October 2, 2023. In total, 20 records were included in the final review. Data from preclinical and clinical studies supported the review.

RESULTS

Since 2020, 20 reports of adverse events, most described as drug-induced liver injury associated with the use of SARM agonists, have been published. The main symptoms mentioned were cholestatic or hepatocellular liver injury and jaundice. Limited data are related to the dosages and purity of SARM supplements.

CONCLUSION

Promoting SARMs as an anabolic agent in combination with other performance-enhancing drugs poses a risk to users not only due to doping controls but also to health safety. The lack of quality control of consumed supplements makes it very difficult to assess the direct impact of SARMs on the liver and their potential hepatotoxic effects. Therefore, more detailed analyses are needed to determine the safety of using SARMs.

RAD140 (Testolone) negatively impacts skeletal muscle adaptation, frailty status and mortality risk in female mice

RAD140 is a selective androgen receptor modulator that produces anabolic effects within skeletal muscle. Thus, RAD140 may be effective at treating sarcopenia. No long-term studies have investigated how RAD140 influences strength in ageing muscle. This study aimed to determine how 10 weeks of RAD140 supplementation impacts strength, recovery from exercise, and overall health in ageing mice. Young and adult females were assigned to receive RAD140 (5 mg/kg) or a control solution. Dorsiflexor muscles were exposed to repeated bouts of eccentric contractions, and torque was measured before and after each bout. Adaptive potential and strength gains were calculated to assess the efficacy of RAD140 in muscle, while frailty status and mortality risk were used to measure health span. Supplementation of RAD140 increased frailty status and mortality risk in the young and adult treated groups compared to the controls (p ≤ 0.042). RAD140 decreased adaptive potential in young (p = 0.040) but not adult mice (p = 0.688). Torque did not differ between groups after 2-3 weeks of recovery (p ≥ 0.135). In conclusion, long-term RAD140 supplementation reduced indices of overall health and failed to improve strength in female mice, suggesting that RAD140 (at a 5mg/kg dosage) may be more detrimental than beneficial in delaying or preventing sarcopenia.

International Union of Basic and Clinical Pharmacology CXIII: Nuclear Receptor Superfamily-Update 2023

The NR superfamily comprises 48 transcription factors in humans that control a plethora of gene network programs involved in a wide range of physiologic processes. This review will summarize and discuss recent progress in NR biology and drug development derived from integrating various approaches, including biophysical techniques, structural studies, and translational investigation. We also highlight how defective NR signaling results in various diseases and disorders and how NRs can be targeted for therapeutic intervention via modulation via binding to synthetic lipophilic ligands. Furthermore, we also review recent studies that improved our understanding of NR structure and signaling. SIGNIFICANCE STATEMENT: Nuclear receptors (NRs) are ligand-regulated transcription factors that are critical regulators of myriad physiological processes. NRs serve as receptors for an array of drugs, and in this review, we provide an update on recent research into the roles of these drug targets.

Sex-specific cytotoxicity of ostarine in cardiomyocytes

Ostarine is the most popular compound in the selective androgen receptor modulator group (SARMs). Ostarine is used as a physical performance-enhancing agent. The abuse of this agent in higher doses may lead to severe side effects. Here, we evaluate the effects of ostarine on the heart. We utilized a cardiomyocyte H9C2 cell line, isolated primary female and male cardiac fibroblast cells, as well as hearts obtained from rats. Ostarine increased the accumulation of two fibrosis protein markers, αSMA and fibronectin (p < 00.1) in male, but not in female fibroblast cells. Ostarine increased the expression of the cardiomyopathy marker βMhc in the H9C2 cell line (p < 0.05) and in the heart in rats (p < 0.01). The unfavorable changes were observed at high ostarine doses. Moreover, a decrease in viability and an increase in cytotoxicity marker LDH were observed already at lowest dose (1 nmoL/l). Taken together, our results suggest that ostarine is cardiotoxic which may be more relevant in males than in females.

Type 2 Diabetes Mellitus and Sarcopenia as Comorbid Chronic Diseases in Older Adults: Established and Emerging Treatments and Therapies

Type 2 diabetes mellitus (T2DM) and sarcopenia (low skeletal muscle mass and function) share a bidirectional relationship. The prevalence of these diseases increases with age and they share common risk factors. Skeletal muscle fat infiltration, commonly referred to as myosteatosis, may be a major contributor to both T2DM and sarcopenia in older adults via independent effects on insulin resistance and muscle health. Many strategies to manage T2DM result in energy restriction and subsequent weight loss, and this can lead to significant declines in muscle mass in the absence of resistance exercise, which is also a first-line treatment for sarcopenia. In this review, we highlight recent evidence on established treatments and emerging therapies targeting weight loss and muscle mass and function improvements in older adults with, or at risk of, T2DM and/or sarcopenia. This includes dietary, physical activity and exercise interventions, new generation incretin-based agonists and myostatin-based antagonists, and endoscopic bariatric therapies. We also highlight how digital health technologies and health literacy interventions can increase uptake of, and adherence to, established and emerging treatments and therapies in older adults with T2DM and/or sarcopenia.

YK11 induces oxidative stress and mitochondrial dysfunction in hippocampus: The interplay between a selective androgen receptor modulator (SARM) and exercise

Our study investigates potential neurochemical effects of (17α,20E)- 17,20-[(1-methoxyethylidene)bis(oxy)]- 3-oxo-19-norpregna-4,20-diene-21-carboxylic acid methyl ester (YK11), a selective androgen receptor modulator (SARM), in the rat hippocampus, with a particular focus on oxidative stress and mitochondrial function, as well as its potential effect when combined with exercise (EXE). To validate YK11's anabolic potential, we performed a molecular docking analysis with the androgen receptor (AR), which showed high affinity with YK11, highlighting hydrogen interactions in Arg752. During the five-week protocol, we divided male Wistar rats into the following groups: Control, YK11 (0.35 g/kg), EXE (swimming protocol), and EXE+YK11. The administration of YK11 resulted in alterations in the endogenous antioxidant system, promoting increased oxidative stress and proteotoxic effects, impairing all mitochondrial function markers in the hippocampus. In contrast, EXE alone had a neuroprotective effect, increasing antioxidant defenses and improving mitochondrial metabolism. When combined, EXE+YK11 prevented alterations in some mitochondrial toxicity markers, including MnSOD/SOD2 and MTT reduction capacity, but did not reverse YK11's neurochemical impairments regarding increased oxidative stress and dysfunction of the mitochondrial respiratory chain and mitochondrial dynamics regulatory proteins in the hippocampus. In summary, our study identifies important pathways of YK11's hippocampal effects, revealing its potential to promote oxidative stress and mitochondrial dysfunction, suggesting that the administration of YK11 may pose potential neurological risks for athletes and bodybuilders seeking to enhance performance. These findings highlight the need for further research to assess the safety and efficacy of YK11 and SARM use in humans.

Evaluation and management of body composition changes in cancer patients

Wasting in cancer patients has long been recognized as a condition that adversely affects cancer patients' quality of life, treatment tolerance, and oncological outcomes. Historically, this condition was mainly evaluated by changes in body weight. However, this approach is not quite accurate because body weight is the overall change of all body compartments. Conditions such as edema and ascites can mask the severity of muscle and adipose tissue depletion. Changes in body composition assessment in cancer patients have historically been underappreciated because of the limited availability of measurement tools. As more evidence highlighting the importance of body composition has emerged, it is imperative to apply a more precise evaluation of nutritional status and a more targeted approach to provide nutritional support for cancer patients. In this review, we will discuss the modalities for evaluating body composition and how to manage body composition changes in cancer patients.

Muscle: an independent contributor to the neuromuscular spinal muscular atrophy disease phenotype

Spinal muscular atrophy (SMA) is a pediatric-onset neuromuscular disorder caused by insufficient survival motor neuron (SMN) protein. SMN restorative therapies are now approved for the treatment of SMA; however, they are not curative, likely due to a combination of imperfect treatment timing, inadequate SMN augmentation, and failure to optimally target relevant organs. Here, we consider the implications of imperfect treatment administration, focusing specifically on outcomes for skeletal muscle. We examine the evidence that muscle plays a contributing role in driving neuromuscular dysfunction in SMA. Next, we discuss how SMN might regulate the health of myofibers and their progenitors. Finally, we speculate on therapeutic outcomes of failing to raise muscle SMN to healthful levels and present strategies to restore function to this tissue to ensure better treatment results.

Selective Androgen Receptor Modulators Combined with Treadmill Exercise Have No Bone Benefit in Healthy Adult Rats

The effects of combination treatments using the selective androgen receptor modulators (SARMs) ostarine (OST) or ligandrol (LIG) with treadmill exercise (TE) were studied in healthy adult rats. Fifteen-week-old male Wistar rats were divided into groups (n = 10/group). Experiment 1 consisted of (1) Control group: sedentary rats receiving vehicle; (2) OST: sedentary rats receiving OST; (3) TE: training rats receiving vehicle; (4) OST + TE: training rats receiving OST. Experiment 2 consisted of (1) LIG: sedentary group receiving LIG; (2) LIG + TE: training group receiving LIG. The TE regime was as follows: 25 m/min, 5° elevation, 40 min, five times/week, and the sedentary regime was 5 min, three times/week. OST and LIG were administered subcutaneously (0.4 mg/kg body weight/day, five times/week). After eight weeks, bone samples underwent microcomputed tomographical, biomechanical, histological, and ashing analyses. All the treatments had weak effects on the bone structure without affecting bone biomechanics. The OST + TE improved bone structure, while the LIG + TE had unfavorable effects. In serum, OST, OST + TE, and LIG + TE altered cholesterol and lipoprotein levels; TE did not change the serum parameters. The SARM treatments had no clear bone benefit, and the serum effects can be considered as side effects. TE represents a safe treatment. Because SARMs are increasingly applied in gyms along with physical activities, attention should be paid to possible side effects.

A Single-Center, Randomized, Double-Blind, and Placebo-Controlled Comparative Human Study to Verify the Functionality and Safety of the Lespedeza cuneata G. Don Extract for the Improvement of Aging Male Syndrome

OBJECTIVE

Aging male syndrome is a clinical biochemical syndrome characterized by typical aging symptoms and serum testosterone deficiency. Although it is accompanied by various health problems, directly affects life satisfaction, and requires proper management, no clear prevention or treatment other than hormone replacement therapy is currently available for this syndrome. Here, we aimed to determine the efficacy and safety of the Lespedeza cuneata extract in the management of the aging male syndrome.

METHODS

Males aged 43-70 years who provided consent for participation and had a total Aging Males' Symptom questionnaire score ≥ 37 and testosterone level ≤ 500 ng/dL were enrolled in this study. This study was conducted in a randomized, double-blind manner. Participants were randomly assigned to either the experimental or control groups and orally administered the assigned product twice a day. Efficacy was evaluated by measuring changes in Aging Males' Symptom score, Androgen Deficiency in the Aging Male questionnaire score, International Index of Erectile Function score, International Prostatic Symptom Score, blood test results, and body mass index at 8 weeks.

RESULTS

After 8 weeks, the experimental group had significantly improved symptom scores compared to the control group on the Aging Males' Symptom and Androgen Deficiency in the Aging Male questionnaires. However, no significant differences in the International Index of Erectile Function score, International Prostatic Symptom Score score, blood test results, and body mass index were observed between the experimental and control groups.

CONCLUSION

Lespedeza cuneata extract safely alleviates andropause symptoms without any significant side effects, suggesting its potential for the treatment of the aging male syndrome.

Treatment of osteoporosis using a selective androgen receptor modulator ostarine in an orchiectomized rat model

PURPOSE

The selective androgen receptor modulator ostarine has been shown to have advantageous effects on skeletal tissue properties, reducing muscle wasting and improving physical function in males. However, data on effects in male osteoporosis remain limited. In this study, the effects of ostarine on osteoporotic bone were evaluated in a rat model of male osteoporosis and compared with those of testosterone treatments.

METHODS

Eight-month-old male Sprague-Dawley rats were either non-orchiectomized to serve as a healthy control (Non-Orx, Group 1) or orchiectomized (Orx, Groups 2-6) and then grouped (n = 15/group): (1) Non-Orx, (2) Orx, (3) Ostarine Therapy, (4) Testosterone Therapy, (5) Ostarine Prophylaxis and (6) Testosterone Prophylaxis. Prophylaxis treatments started directly after orchiectomy and continued for 18 weeks, whereas Therapy treatments were initiated 12 weeks after Orx. Ostarine and Testosterone were applied orally at daily doses of 0.4 and 50 mg/kg body weight, respectively. The lumbar vertebral bodies and femora were analyzed using biomechanical, micro-CT, ashing, and gene expression analyses.

RESULTS

Ostarine Prophylaxis showed positive effects in preventing osteoporotic changes in cortical and trabecular bone (femoral trabecular density: 26.01 ± 9.1% vs. 20.75 ± 1.2% in Orx and in L4: 16.3 ± 7.3% vs 11.8 ± 2.9% in Orx); biomechanical parameters were not affected; prostate weight was increased (0.62 ± 0.13 g vs 0.18 ± 0.07 g in Orx). Ostarine Therapy increased solely the cortical density of the femur (1.25 ± 0.03 g/cm3 vs. 1.18 ± 0.04 g/cm3 in Orx); other bone parameters remained unaffected. Testosteron Prophylaxis positively influenced cortical density in femur (1.24 ± 0.05 g/cm3 vs. 1.18 ± 0.04 g/cm3 in Orx); Test. Therapy did not change any bony parameters.

CONCLUSION

Ostarine Prophylaxis could be further investigated as a preventative treatment for male osteoporosis, but an androgenic effect on the prostate should be taken into consideration, and combination therapies with other anti-osteoporosis agents could be considered.

The androgen receptor

The Androgen Receptor (AR) is a ligand (androgen) activated transcription factor and a member of the nuclear receptor (NR) superfamily. It is required for male sex hormone function. AR-FL (full-length) has the domain structure of NRs, an N-terminal domain (NTD) required for transactivation, a DNA-binding domain (DBD), a nuclear localization signal (NLS) and a ligand-binding domain (LBD). Paradoxes exist in that endogenous ligands testosterone (T) and 5α-dihydrotestosterone (DHT) have differential effects on male sexual development while binding to the same receptor and transcriptional specificity is achieved even though the androgen response elements (AREs) are identical to those seen for the progesterone, glucocorticoid and mineralocorticoid receptors. A high resolution 3-dimensional structure of AR-FL by either cryo-EM or X-ray crystallography has remained elusive largely due to the intrinsic disorder of the NTD. AR function is regulated by post-translational modification leading to a large number of proteoforms. The interaction of these proteoforms in multiprotein complexes with co-activators and co-repressors driven by interdomain coupling mediates the AR transcriptional output. The AR is a drug target for selective androgen receptor modulators (SARMS) that either have anabolic or androgenic effects. Protstate cancer is treated with androgen deprivation therapy or by the use of AR antagonists that bind to the LBD. Drug resistance occurs due to adaptive AR upregulation and the appearance of splice variants that lack the LBD and become constitutively active. Bipolar T treatment and NTD-antagonists could surmount these resistance mechanisms, respectively. These recent advances in AR signaling are described.

Androgen Receptor and Cardiovascular Disease: A Potential Risk for the Abuse of Supplements Containing Selective Androgen Receptor Modulators

The androgen receptor (AR) is a member of the family of ligand-activated transcription factors. Selective androgen receptor modulators (SARMs) exert their biological function through complex interactions with the AR. It has been speculated that overexertion of AR signaling cascades as a result of SARM abuse can be a risk factor for the development of various cardiovascular diseases. The present literature review explores the implications of the interaction between SARMs and the AR on cardiovascular health by focusing on the AR structure, function, and mechanisms of action, as well as the current clinical literature on various SARMs. It is shown that SARMs may increase the risk of cardiovascular diseases through implications on the renin-angiotensin system, smooth muscle cells, sympathetic nervous system, lipid profile, inflammation, platelet activity, and various other factors. More research on this topic is necessary as SARM abuse is becoming increasingly common. There is a noticeable lack of clinical trials and literature on the relationship between SARMs, cardiovascular diseases, and the AR. Future in vivo and in vitro studies within this field are vital to understand the mechanisms that underpin these complex interactions and risk factors.

Nuclear lamin A/C phosphorylation by loss of Androgen Receptor is a global determinant of cancer-associated fibroblast activation

Alterations of nuclear structure and function, and associated impact on gene transcription, are a hallmark of cancer cells. Little is known of these alterations in Cancer-Associated Fibroblasts (CAFs), a key component of the tumor stroma. Here we show that loss of androgen receptor (AR), which triggers early steps of CAF activation in human dermal fibroblasts (HDFs), leads to nuclear membrane alterations and increased micronuclei formation, which are unlinked from induction of cellular senescence. Similar alterations occur in fully established CAFs, which are overcome by restored AR function. AR associates with nuclear lamin A/C and loss of AR results in a substantially increased lamin A/C nucleoplasmic redistribution. Mechanistically, AR functions as a bridge between lamin A/C with the protein phosphatase PPP1. In parallel with a decreased lamin-PPP1 association, AR loss results in a marked increase of lamin A/C phosphorylation at Ser 301, which is also a feature of CAFs. Phosphorylated lamin A/C at Ser 301 binds to the transcription promoter regulatory region of several CAF effector genes, which are upregulated due to the loss of AR. More directly, expression of a lamin A/C Ser301 phosphomimetic mutant alone is sufficient to convert normal fibroblasts into tumor-promoting CAFs of the myofibroblast subtype, without an impact on senescence. These findings highlight the pivotal role of the AR-lamin A/C-PPP1 axis and lamin A/C phosphorylation at Ser 301 in driving CAF activation.

Androgens and Selective Androgen Receptor Modulators to Treat Functional Limitations Associated With Aging and Chronic Disease

Testosterone, many steroidal androgens, and nonsteroidal ligands that bind to androgen receptor and exert tissue-specific transcriptional activity (selective androgen receptor modulators [SARMs]) are being developed as function-promoting therapies to treat functional limitations associated with aging and chronic diseases. This narrative review describes preclinical studies, mechanisms, and randomized trials of testosterone, other androgens, and nonsteroidal SARMs. Sex differences in muscle mass and strength and empiric use of anabolic steroids by athletes to increase muscularity and athletic performance provide supportive evidence of testosterone's anabolic effects. In randomized trials, testosterone treatment increases lean body mass, muscle strength, leg power, aerobic capacity, and self-reported mobility. These anabolic effects have been reported in healthy men, hypogonadal men, older men with mobility limitation and chronic diseases, menopausal women, and HIV-infected women with weight loss. Testosterone has not consistently improved walking speed. Testosterone treatment increases volumetric and areal bone mineral density, and estimated bone strength; improves sexual desire, erectile function, and sexual activity; modestly improves depressive symptoms; and corrects unexplained anemia in older men with low testosterone levels. Prior studies have not been of sufficient size or duration to determine testosterone's cardiovascular and prostate safety. The efficacy of testosterone in reducing physical limitations, fractures, falls, progression to diabetes, and correcting late-onset persistent depressive disorder remains to be established. Strategies to translate androgen-induced muscle mass and strength gains into functional improvements are needed. Future studies should evaluate the efficacy of combined administration of testosterone (or a SARM) plus multidimensional functional exercise to induce neuromuscular adaptations required for meaningful functional improvements.

Metabolic study of selective androgen receptor modulator LY2452473 in thoroughbred horses for doping control

RATIONALE

Since 2010, there has been an increasing number of adverse analytical findings related to selective androgen receptor modulators (SARMs) in competitive sports. It emphasizes the importance of comprehensive doping control analytical procedures that are capable of detecting SARM misuse.

METHODS

In this study, it is described how LY2452473, a SARM, was metabolized in thoroughbred horses after a single-dose oral administration and in vitro with equine liver microsome preparations. An investigation of the metabolism of LY2452473 in horses' urine, plasma, and hair matrices was carried out during the study. The plausible structures of the detected metabolites were postulated using high-performance liquid chromatography-high resolution mass spectrometry.

RESULTS

Under the experimental conditions 15 metabolites (12 phase I and three conjugates of phase I) were detected (M1-M15). The major phase I metabolites identified were formed by hydroxylation. Side-chain dissociated and methylated metabolites were also detected. In phase II, the glucuronic acid and sulfonic acid conjugates of hydroxy LY2452473 were detected as the major metabolites. In vitro analysis has confirmed the presence of all metabolites found in vivo except for the methylated analogs M11 and M12. A peak concentration of LY2452473 (0.5 pg/mg) in proximal hair segments was achieved 4 weeks after administration, according to hair analysis.

CONCLUSIONS

Data obtained will aid in identifying LY2452473 and related substances faster. Furthermore, the results will assist in checking for the illegal use of these substances in competitive sports.

The molecular consequences of androgen activity in the human breast

Estrogen and progesterone have been extensively studied in the mammary gland, but the molecular effects of androgen remain largely unexplored. Transgender men are recorded as female at birth but identify as male and may undergo gender-affirming androgen therapy to align their physical characteristics and gender identity. Here we perform single-cell-resolution transcriptome, chromatin, and spatial profiling of breast tissues from transgender men following androgen therapy. We find canonical androgen receptor gene targets are upregulated in cells expressing the androgen receptor and that paracrine signaling likely drives sex-relevant androgenic effects in other cell types. We also observe involution of the epithelium and a spatial reconfiguration of immune, fibroblast, and vascular cells, and identify a gene regulatory network associated with androgen-induced fat loss. This work elucidates the molecular consequences of androgen activity in the human breast at single-cell resolution.

Selective androgen receptor modulation for muscle weakness in chronic obstructive pulmonary disease: a randomised control trial

BACKGROUND

Selective androgen receptor modulators (SARMs) increase muscle mass via the androgen receptor. This phase 2A trial investigated the effects of a SARM, GSK2881078, in conjunction with exercise, on leg strength in patients with chronic obstructive pulmonary disease (COPD) and impaired physical function.

METHODS

47 postmenopausal women and 50 men with COPD (forced expiratory volume in 1 s 30%-65% predicted; short physical performance battery score: 3-11) were enrolled into a randomised double-blind, placebo control trial. Patients were randomised 1:1 to once daily placebo or oral GSK2881078 (females: 1.0 mg; males: 2.0 mg) for 13 weeks with a concurrent home-exercise programme, involving strength training and physical activity. Primary endpoints were change from baseline in leg strength at 90 days (one-repetition maximum; absolute (kg) and relative (% change)) and multiple safety outcomes. Secondary endpoints included lean body mass, physical function and patient-reported outcomes.

RESULTS

GSK2881078 increased leg strength in men. The difference in adjusted mean change from baseline and adjusted mean percentage change from baseline between treatment and placebo were: for women, 8.0 kg (90% CI -2.5 to 18.4) and 5.2% (90% CI -4.7 to 15.0), respectively; for men, 11.8 kg (90% CI -0.5 to 24.0) and 7.0% (90% CI 0.5 to 13.6), respectively. Lean body mass increased, but no changes in patient-reported outcomes were observed. Reversible reductions in high-density lipoprotein-cholesterol and transient elevations in hepatic transaminases were the main treatment-related safety findings.

CONCLUSIONS

GSK2881078 was well tolerated and short-term treatment increased leg strength, when expressed as per cent predicted, in men with COPD more than physical training alone.

TRIAL REGISTRATION NUMBER

NCT03359473.

Investigation of in vitro generated metabolites of GLPG0492 using equine liver microsomes for doping control

An effective alternative to testosterone therapy is selective androgen receptor modulators, a class of compounds that has a tissue-specific effect on muscle and bone. These drugs, which enhance performance, pose a severe abuse risk in competitive sports. GLPG0492 is one of the selective androgen receptor modulators discovered in recent decades. This compound has a unique tissue-specific action for muscle and bone against steroid receptors and acts as a partial agonist for androgen receptors. This study examined GLPG0492 and its metabolites in vitro using equine liver microsomes. Liquid chromatography-high-resolution mass spectrometry was utilized to determine the probable structures of detected metabolites. This study identified 39 metabolites of GLPG0492 (21 phase I and 18 phase II). The hydroxylation of GLPG0492 results in monohydroxylated and dihydroxylated metabolites. Additionally, the study detected dissociated side chains (3-methyl and 4-(hydroxymethyl)) and corresponding hydroxylated metabolites. A series of glucuronic acid- and sulfonic acid-conjugated analogs of GLPG0492 were detected during phase II of the study. The findings might help in the detection of GLPG0492 and the elucidation of its illegal use in equestrian sports.

Adverse effects and potential benefits among selective androgen receptor modulators users: a cross-sectional survey

Selective androgen receptor modulators (SARMs) are a class of androgen receptor ligands that bind androgen receptors and display tissue selective activation of androgenic signaling. SARMs have selective anabolic effects on muscle and bone, and were originally synthesized for treatment of muscle wasting conditions, osteoporosis, breast cancer. To date, no SARM has been clinically approved and little is known about the beneficial effects and other adverse effects on users. We examined the adverse effects and potential benefits of SARMs amongst users. We performed an internet survey assessing the demographics of users via a 32-question survey. Using reddit as a platform, we distributed the survey through various subreddits that included potential SARMs users. Out of the 520 responses, 343 participants admitted having used SARMs. Most were males (98.5%), between the ages of 18-29 (72.3%). More than 90% of users acquired SARMs via the internet and did not consult with a physician. More than half of SARMs users experienced side effects including mood swings, decreased testicular size, and acne. More than 90% of men reported increased muscle mass and were satisfied with their SARMs usage. Despite having seemingly positive effects, more than 50% of SARMs users report significant adverse effects. Chi square was the main method of statistical analysis. Future studies should focus on comprehensive reproductive evaluation of men using SARMs.

Molecular docking and molecular dynamics simulation study the mechanism of progesterone in the treatment of spinal cord injury

PURPOSE

Spinal cord injury can lead to incomplete or complete loss of voluntary movement and sensory function, leading to serious complications. Numerous studies have shown that progesterone exhibits strong therapeutic potential for spinal cord injury. However, the mechanism by which progesterone treats spinal cord injury remains unclear. Therefore, this article explores the mechanism of progesterone in the treatment of spinal cord injury by means of molecular docking and molecular dynamics simulation.

METHODS

We used bioinformatics to screen active pharmaceutical ingredients and potential targets, and molecular docking and molecular dynamics were used to validate and analysis by the supercomputer platform.

RESULTS

Progesterone had 3606 gene targets, spinal cord injury had 6560 gene targets, the intersection gene targets were 2355. GO and KEGG analysis showed that the abundant pathways involved multiple pathways related to cell metabolism and inflammation. Molecular docking showed that progesterone played a role in treating spinal cord injury by acting on BDNF, AR, NGF and TNF. Molecular dynamics was used to prove and analyzed the binding stability of active ingredients and protein targets, and AR/Progesterone combination has the strongest binding energy.

CONCLUSION

Progesterone promotes recovery from spinal cord injury by promoting axonal regeneration, remyelination, neuronal survival and reducing inflammation.

Doping and sports endocrinology: anabolic-androgenic steroids

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.

A combined treatment with selective androgen and estrogen receptor modulators prevents bone loss in orchiectomized rats

PURPOSE

Enobosarm (EN), a selective androgen receptor modulator and raloxifene (RAL), a selective estrogen receptor modulator, have been shown to improve bone tissue in osteoporotic males. The present study evaluated the effects of a combination therapy of EN and RAL on bone properties in orchiectomized rats compared to the respective single treatments.

METHODS

Eight-month-old male Sprague-Dawley rats were either left intact (Non-Orx) or orchiectomized (Orx). The Orx rats were divided into four groups (n = 15 each): 1) Orx, 2) EN treatment (Orx + EN), 3) RAL treatment (Orx + RAL), 4) combined treatment (Orx + EN + RAL). EN and RAL (0.4 mg and 7 mg/kg body weight/day) were applied immediately after Orx with a soy-free pelleted diet for up to 18 weeks. The lumbar spine and femora were examined by micro-CT, biomechanical, histomorphological, ashing, and gene expression analyses.

RESULTS

EN exhibited an anabolic effect on bone, improving some of its parameters in Orx rats, but did not affect biomechanical properties. RAL exhibited antiresorptive activity, maintaining the biomechanical and trabecular parameters of Orx rats at the levels of Non-Orx rats. EN + RAL exerted a stronger effect than the single treatments, improving most of the bone parameters. Liver weight increased after all treatments; the kidney, prostate, and levator ani muscle weights increased after EN and EN + RAL treatments. BW was reduced due to a decreased food intake in the Orx + RAL group and due a reduced visceral fat weight in the Orx + EN + RAL group.

CONCLUSION

The EN + RAL treatment appeared to be promising in preventing male osteoporosis, but given the observed side effects on liver, kidney, and prostate weights, it requires further investigation.

LGD-4033 and MK-677 use impacts body composition, circulating biomarkers, and skeletal muscle androgenic hormone and receptor content: A case report

NEW FINDINGS

What is the main observation in this case? Co-administration of LGD-4033 and MK-677 increased body mass, lean mass and fat mass, while negatively impacting bone, serum lipids, liver enzymes, testosterone (total and free) and, probably, follicle-stimulating hormone. What insights does it reveal? Our cross-sectional data imply that these compounds might alter intramuscular androgenic hormone and receptor concentrations along with promoting muscular strength, when compared with previously published data from trained males.

ABSTRACT

LGD-4033, a selective androgen receptor modulator, and MK-677, a growth hormone secretagogue, are being used increasingly amongst recreationally active demographics. However, limited data exist describing their effects on health- and androgen-related biomarkers. The purpose of this case study was to determine changes in body composition and biomarkers during and after continued co-administration of LGD-4033 and MK-677. We also aimed to examine muscular strength and intramuscular androgen-associated biomarkers relative to non-users. A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks. Blood and body composition metrics were obtained pre-, on- and post-cycle. One-repetition maximum leg and bench press, in addition to intramuscular androgens and androgen receptor content, were analysed on-cycle. We observed pre- to on-cycle changes in body composition (body mass, +6.0%; total lean body mass, +3.1%; trunk lean body mass, +6.6%; appendicular lean body mass, +4.3%; total fat mass, +15.4%; trunk fat mass, +2.8%; and appendicular fat mass, +14.8%), bone (bone mineral content, -3.60%; area, -1.1%; and bone mineral density, -2.1%), serum lipid-associated biomarkers (cholesterol, +14.8%; triglycerides, +39.2%; low-density lipoprotein-cholesterol, +40.0%; and high-density lipoprotein-cholesterol, -36.4%), liver-associated biomarkers (aspartate aminotransferase, +95.8%; and alanine aminotransferase, +205.0%) and androgen-associated biomarkers (free testosterone, -85.7%; total testosterone, -62.3%; and sex hormone-binding globulin, -79.6%); however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol. Follicle-stimulating hormone was below clinical reference values on- (1.2 IU/L) and post-cycle (1.3 IU/L). Intramuscular androgen receptor (-44.6%), testosterone (+47.8%) and dihydrotestosterone (+34.4%), in addition to one-repetition maximum leg press and bench press (+39.2 and +32.0%, respectively), were different in the case subject compared with non-users. These data demonstrate that LGD-4033 and MK-677 increase several body composition parameters, whilst negatively impacting bone and several serum biomarkers. Given the sparsity of data in recreationally using demographics, further research is warranted to elucidate the acute and chronic physiological effects of these anabolic agents.

The anabolic applications of androgens in older adults with functional limitations

Aging is associated with a progressive decrease in skeletal muscle mass, strength and power and impairment of physical function. Serum testosterone concentrations in men decrease with advancing age due to defects at all levels of the hypothalamic-pituitary-testicular axis. Testosterone administration increases skeletal muscle mass, strength and power in older men with low or low normal testosterone levels, but the effects on performance-based measures of physical function have been inconsistent. Adequately powered randomized trials are needed to determine the long-term safety and efficacy of testosterone in improving physical function and quality of life in older adults with functional limitations.

Sarcopenia and bone health: new acquisitions for a firm liaison

Osteosarcopenia (OS) is a newly defined condition represented by the simultaneous presence of osteopenia/osteoporosis and sarcopenia, the main age-related diseases. The simultaneous coexistence of the two phenotypes derives from the close connection of the main target tissues involved in their pathogenesis: bone and muscle. These two actors constitute the bone-muscle unit, which communicates through a biochemical and mechanical crosstalk which involves multiple factors. Altered pattern of molecular pathways leads to an impairment of both the functionality of the tissue itself and the communication with the complementary tissue, composing the OS pathogenesis. Recent advances in the genetics field have provided the opportunity to delve deeper into the complex biological and molecular mechanisms underlying OS. Unfortunately, there are still many gaps in our understanding of these pathways, but it has proven essential to apply strategies such as exercise and nutritional intervention to counteract OS. New therapeutic strategies that simultaneously target bone and muscle tissue are limited, but recently new targets for the development of dual-action drug therapies have been identified. This narrative review aims to provide an overview of the latest scientific evidence associated with OS, a complex disorder that will pave the way for future research aimed at understanding the bone-muscle-associated pathogenetic mechanisms.

Dual-Acting Peptides Target EZH2 and AR: A New Paradigm for Effective Treatment of Castration-Resistant Prostate Cancer

Prostate cancer starts as a treatable hormone-dependent disease, but often ends in a drug-resistant form called castration-resistant prostate cancer (CRPC). Despite the development of the antiandrogens enzalutamide and abiraterone for CRPC, which target the androgen receptor (AR), drug resistance usually develops within 6 months and metastatic CRPC (mCRPC) leads to lethality. EZH2, found with SUZ12, EED, and RbAP48 in Polycomb repressive complex 2 (PRC2), has emerged as an alternative target for the treatment of deadly mCRPC. Unfortunately, drugs targeting EZH2 have shown limited efficacy in mCRPC. To address these failures, we have developed novel, dual-acting peptide inhibitors of PRC2 that uniquely target the SUZ12 protein component, resulting in the inhibition of both PRC2 canonical and noncanonical functions in prostate cancer. These peptides were found to inhibit not only the EZH2 methylation activity, but also block its positive effect on AR gene expression in prostate cancer cells. Since the peptide effect on AR levels is transcriptional, the inhibitory peptides can block the expression of both full-length AR and its splicing variants including AR-V7, which plays a significant role in the development of drug resistance. This dual-mode action provides the peptides with the capability to kill enzalutamide-resistant CRPC cells. These peptides are also more cytotoxic to prostate cancer cells than the combination of enzalutamide and an EZH2 inhibitory drug, which was recently suggested to be an effective treatment of mCRPC disease. Our data show that such a dual-acting therapeutic approach can be more effective than the existing front-line drug therapies for treating deadly mCRPC.