ABSTRACT
PURPOSE: Cardiac abnormalities are common in patients with acromegaly, contributing to the increased morbidity and mortality. Cardiac magnetic resonance (CMR) is the gold standard for measuring cardiac morpho-functional changes. This study aims to detect cardiac alterations in acromegaly through CMR, even when the disease is adequately controlled. METHODS: In this, multicentre, case-control study, we compared consecutive patients with acromegaly, cured after surgery or requiring medical treatment, with matched controls recruited among patients harbouring non-functioning adrenal incidentalomas. RESULTS: We included 20 patients with acromegaly (7 females, mean age 50 years) and 17 controls. Indexed left ventricular-end-diastolic volume (LV-EDVi) and LV-end-systolic volume (LV-ESVi) were higher in patients than in controls (p < 0.001), as were left ventricular mass (LVMi) (p = 0.001) and LV-stroke volume (LV-SVi) (p = 0.028). Right ventricle (RV) EDVi and ESVi were higher, whereas RV-ejection fraction (RV-EF) was lower (p = 0.002) in patients than in controls (p < 0.001). No significant differences were observed in the prevalence of cardiometabolic comorbidities, including hypertension, glucose and lipid metabolism impairment, obstructive sleep apnoea syndrome, and obesity. IGF1 x upper limit of normal significantly predicted LVMi (b = 0.575; p = 0.008). Subgroup analysis showed higher LVMi (p = 0.025) and interventricular septum thickness (p = 0.003) in male than female patients, even after adjusting cardiac parameters for confounding factors. CONCLUSIONS: The CMR analysis reveals a cluster of biventricular structural and functional impairment in acromegaly, even when the biochemical control if achieved. These findings appear specifically triggered by the exposure to GH-IGF1 excess and show sex-related differences advocating a possible interaction with sex hormones in cardiac disease progression.
Subject(s)
Acromegaly , Magnetic Resonance Imaging , Humans , Female , Acromegaly/diagnostic imaging , Acromegaly/pathology , Acromegaly/complications , Male , Middle Aged , Case-Control Studies , Adult , Aged , Heart/diagnostic imaging , Heart/physiopathologyABSTRACT
PURPOSE: Cushing's syndrome (CS) is associated with severe cardiovascular (CV) morbidity and mortality. Cardiac magnetic resonance (CMR) is the non-invasive gold standard for assessing cardiac structure and function; however, few CMR studies explore cardiac remodeling in patients exposed to chronic glucocorticoid (GC) excess. We aimed to describe the CMR features directly attributable to previous GC exposure in patients with cured or treated endogenous CS. METHODS: This was a prospective, multicentre, case-control study enrolling consecutive patients with cured or treated CS and patients harboring non-functioning adrenal incidentalomas (NFAI), comparable in terms of sex, age, CV risk factors, and BMI. All patients were in stable condition and had a minimum 24-month follow-up. RESULTS: Sixteen patients with CS and 15 NFAI were enrolled. Indexed left ventricle (LV) end-systolic volume and LV mass were higher in patients with CS (p = 0.027; p = 0.013); similarly, indexed right ventricle (RV) end-diastolic and end-systolic volumes were higher in patients with CS compared to NFAI (p = 0.035; p = 0.006). Morphological alterations also affected cardiac function, as LV and RV ejection fractions decreased in patients with CS (p = 0.056; p = 0.044). CMR features were independent of metabolic status or other CV risk factors, with fasting glucose significantly lower in CS remission than NFAI (p < 0.001) and no differences in lipid levels or blood pressure. CONCLUSION: CS is associated with biventricular cardiac structural and functional impairment at CMR, likely attributable to chronic exposure to cortisol excess independently of known traditional risk factors.
Subject(s)
Cushing Syndrome , Humans , Cushing Syndrome/complications , Cushing Syndrome/diagnostic imaging , Female , Male , Middle Aged , Case-Control Studies , Adult , Prospective Studies , Aged , Magnetic Resonance Imaging , Adrenal Gland Neoplasms/complications , Adrenal Gland Neoplasms/diagnostic imaging , Heart Ventricles/diagnostic imaging , Heart Ventricles/physiopathologyABSTRACT
BACKGROUND: Data on sexual function in patients with adrenal insufficiency are scarce and largely controversial. OBJECTIVES: To investigate sexual dysfunction in patients with primary and secondary adrenal insufficiency and the effects of switching to once-daily dual-release hydrocortisone on sexual function in outcome assessors blinded, randomized, multicenter, active comparator clinical trial. MATERIALS AND METHODS: Eighty-nine adrenal insufficiency patients on conventional, multiple daily doses of glucocorticoid replacement, enrolled in the Dual RElease hydrocortisone versus conventionAl glucocorticoid replaceMent in hypocortisolism (DREAM) trial, were randomly assigned to continue their therapy or to switch to an equivalent dose of dual-release hydrocortisone. Sixty-three patients (34 women) consented to sex steroid measurements and questionnaires completion for quality of life (Addison's disease-specific quality-of-life questionnaire) and sexual function evaluation (female sexual function index for women, International Index of Erectile Function-Erectile Function for men) at baseline and 24 weeks after randomization. RESULTS: At baseline, sexual dysfunction was observed in 41% of women and 59% of men with adrenal insufficiency. In both sexes, no associations were found between sexual function and hormone levels, whereas Addison's disease-specific quality-of-life questionnaire total and fatigue domain scores positively correlated with total female sexual function index and International Index of Erectile Function-Erectile Function scores. At 24 weeks, there was no significant difference either in sexual function or sex steroid levels between study groups. In the dual-release hydrocortisone group, the variation in the female sexual function index desire domain score was positively associated with the change in Addison's disease-specific quality-of-life questionnaire's symptom domain score (ρ = 0.478, p = 0.045). DISCUSSION: Sexual dysfunction is common in adrenal insufficiency patients and is likely explained by multiple factors. dual-release hydrocortisone treatment is not directly associated with sexual function improvement, but an indirect effect mediated by quality-of-life amelioration cannot be excluded.
ABSTRACT
Aggressive pituitary tumors are a subset of pituitary neoplasms, characterized by unusually fast growth rate, invasiveness and overall resistance to optimized standard treatment. When metastases are present, the term pituitary carcinoma is employed. After failure of standard treatments, current guidelines recommend first-line temozolomide monotherapy. However, a significant number of patients do not respond to temozolomide, or experience disease progression following its discontinuation; in these latter cases, re-challenge with temozolomide is generally advised, although the reported outcomes have been less satisfactory. Although no alternative therapies have been formally recommended after temozolomide failure, growing evidence regarding potential second- or third-line therapeutic strategies has emerged. In the present work, we reviewed the available evidence published up to April 2023 involving the most relevant therapies employed so far, namely immune checkpoint inhibitors, bevacizumab, peptide radionuclide receptor therapy, tyrosine kinase inhibitors and mTOR inhibitors. For each treatment, we report efficacy and safety outcomes, along with data regarding potential predictors of response. Overall, immune checkpoint inhibitors and bevacizumab are showing the most promise as therapeutic options after temozolomide failure. The former showed better responses in pituitary carcinomas. Peptide radionuclide receptor therapy has also showed some efficacy in these tumors, while tyrosine kinase inhibitors and mTOR inhibitors have exhibited so far limited or no efficacy. Further studies, as well as an individualized, patient-tailored approach, are clearly needed. In addition, we report an unpublished case of a silent corticotroph pituitary carcinoma that progressed under dual immunotherapy, and then showed stable disease under a combination of lomustine and bevacizumab.
ABSTRACT
Since 2017, hormone-negative pituitary neuroendocrine tumors expressing the steroidogenic factor SF1 have been recognized as gonadotroph tumors (GnPT) but have been poorly studied. To further characterize their bio-clinical spectrum, 54 GnPT defined by immunostaining for FSH and/or LH (group 1, n = 41) or SF1 only (group 2, n = 13) were compared and studied for SF1, ßFSH, ßLH, CCNA2, CCNB1, CCND1, caspase 3, D2R, and AIP gene expression by qRT-PCR. Immunohistochemistry for AIP and/or D2R was performed in representative cases. Overall, patients were significantly younger in group 1 (P = 0.040 vs group 2), with a similar trend excluding recurrent cases (P = 0.078), and no significant difference in gender, tumor size, invasion or Ki67. SF1 expression was similar in both groups but negatively correlated with the patient's age (P = 0.013) and positively correlated with ßLH (P < 0.001) expression. Beta-FSH and AIP were significantly higher in group 1 (P = 0.042 and P = 0.024, respectively). Ki67 was unrelated to gonadotroph markers but positively correlated with CCNB1 (P = 0.001) and negatively correlated with CCND1 (P = 0.008). D2R and AIP were strongly correlated with each other (P < 0.001), and both positively correlated with SF1, ßFSH, ßLH, and CCND1. AIP immunopositivity was frequently observed in both groups, with a similar median score, and unrelated to Ki67. D2R immunostaining was best detected with a polyclonal antibody and mostly cytoplasmic. This study indicates that hormone-negative GnPT tend to occur in older patients but do not significantly differ from other GnPT in terms of invasion or proliferation. It also points out the current limits of D2R immunostaining in such tumors.
Subject(s)
Gonadotrophs , Pituitary Neoplasms , Humans , Aged , Pituitary Neoplasms/pathology , Gonadotrophs/metabolism , Gonadotrophs/pathology , Ki-67 Antigen/metabolism , Follicle Stimulating Hormone , World Health OrganizationABSTRACT
Context: Patients with primary (PAI) and secondary adrenal insufficiency (SAI) experience bone metabolism alterations, possibly due to excessive replacement. Dual-release hydrocortisone (DR-HC) has shown promising effects on several parameters, but bone metabolism has seldom been investigated. Objective: We evaluated the long-term effects of once-daily DR-HC on bone in PAI and SAI. Methods: Patients on immediate-release glucocorticoid therapy were evaluated before and up to 6 years (range, 4-6) after switching to equivalent doses of DR-HC, yielding data on bone turnover markers, femoral and lumbar spine bone mineral density (BMD), and trabecular bone score (TBS). Results: Thirty-two patients (19 PAI, 18 female), median age 52 years (39.4-60.7), were included. At baseline, osteopenia was observed in 38% of patients and osteoporosis in 9%, while TBS was at least partially degraded in 41.4%. Higher body surface area-adjusted glucocorticoid doses predicted worse neck (P < .001) and total hip BMD (P < .001). Longitudinal analysis showed no significant change in BMD. TBS showed a trend toward decrease (P = .090). Bone markers were stable, albeit osteocalcin levels significantly varied. PAI and SAI subgroups behaved similarly, as did patients switching from hydrocortisone or cortisone acetate. Compared with men, women exhibited worse decline in TBS (P = .017) and a similar trend for neck BMD (P = .053). Conclusion: After 6 years of chronic DR-HC replacement, BMD and bone markers remained stable. TBS decline is more likely due to an age-related derangement of bone microarchitecture rather than a glucocorticoid effect. Our data confirm the safety of DR-HC replacement on bone health in both PAI and SAI patients.
ABSTRACT
The tumor microenvironment (TME), the complex environment in which tumors develop, has been increasingly targeted for cancer treatment in recent years. Aggressive pituitary tumors and pituitary carcinomas have been so far targeted with immune-checkpoint inhibitors (28 cases, including a large cohort), and anti-angiogenic drugs (34 cases), specifically bevacizumab (30 cases), sunitinib (three cases), and apatinib (one case). Here, we reviewed all these cases, reporting tumor response, potential predictors of response, as well as adverse events. Given that the histological type could potentially influence treatment response, we present the existing data separately for each type. Briefly, under ICIs, complete response was noted in one case, partial response in a third of cases, stable disease in 10% of cases, while 54% of tumors progressed. Under BVZ monotherapy, most cases (57%) showed stable disease, while 36% of tumors progressed; partial response was reported in only one case. The three cases treated with sunitinib monotherapy progressed. Regarding predictive factors of response, the tumor type (aggressive pituitary tumor versus pituitary carcinoma) appears as the strongest predictor of response to ICIs. To date, no predictor of response to anti-angiogenic drugs in the treatment of pituitary carcinomas and aggressive pituitary tumors has been identified. The interest of BZV add-on to first- or second-line chemotherapy warrants further investigation. In addition, we discuss perspectives regarding the TME-targeting in aggressive pituitary tumors and pituitary carcinomas, including perspectives on immunotherapy, anti-angiogenic drugs, as well as on other TME components, namely stromal cells, extracellular matrix, and secreted molecules.
Subject(s)
Angiogenesis Inhibitors , Pituitary Neoplasms , Humans , Angiogenesis Inhibitors/therapeutic use , Sunitinib/therapeutic use , Pituitary Neoplasms/drug therapy , Tumor Microenvironment , Bevacizumab , ImmunotherapyABSTRACT
BACKGROUND: Tumor consistency recently emerged as a key factor in surgical planning for pituitary adenomas, but its impact on postoperative endocrine function is still unclear. Our study aimed to evaluate the impact of tumor consistency on the development of postoperative pituitary deficiencies. METHODS: Single-center, retrospective analysis of consecutive pituitary surgeries performed between January 2017 and January 2021 at Policlinico Umberto I in Rome. All patients underwent radiological and biochemical evaluations at baseline, and hormone assessments 3 and 6 months after pituitary surgery. Postoperative MRI studies were used to determine resection rates following surgery. Data on tumor consistency, macroscopic appearance, neurosurgical approach, and intraoperative complications were collected. RESULTS: Fifty patients [24 women, mean age 57 ± 13 years, median tumor volume 4800 mm3 [95% CI 620-8828], were included. Greater tumor volume (χ2 = 14.621, p = 0.006) and male sex (χ2 = 12.178, p < 0.001) were associated with worse preoperative endocrine function. All patients underwent transsphenoidal adenomectomy. Fibrous consistency was observed in 10% of patients and was associated with a Ki-67 greater than 3% (χ2 = 8.154, p = 0.04), greater risk of developing postoperative hormone deficiencies (χ2 = 4.485, p = 0.05, OR = 8.571; 95% CI: 0.876-83.908), and lower resection rates (χ2 = 8.148, p = 0.004; OR 1.385, 95% CI; 1.040-1.844). Similarly, worse resection rates were observed in tumors with suprasellar extension (χ2 = 5.048, p = 0.02; OR = 6.000, 95% CI; 1.129-31.880) and CSI (χ2 = 4.000, p = 0.04; OR = 3.857, 95% CI; 0.997-14.916). CONCLUSIONS: Tumor consistency might provide useful information about postoperative pituitary function, likely due to its impact on surgical procedures. Further prospective studies with larger cohorts are needed to confirm our preliminary findings.
Subject(s)
Adenoma , Pituitary Neoplasms , Humans , Male , Female , Adult , Middle Aged , Aged , Pituitary Neoplasms/diagnostic imaging , Pituitary Neoplasms/surgery , Pituitary Neoplasms/complications , Retrospective Studies , Prospective Studies , Adenoma/pathology , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Hormones , Treatment OutcomeABSTRACT
Pituitary tumours are benign neoplasms that derive from hormone-producing cells of the pituitary gland. While medical treatments have emerged for most subtypes, gonadotroph tumours that express follicle-stimulating hormone (FSH) and/or luteinizing hormone still lack therapeutic options apart from surgery and radiotherapy. Activin ligands are physiological regulators of production and secretion of FSH by gonadotroph cells, but their role in gonadotroph tumourigenesis remains little explored. Using the LßT2 mouse gonadotroph cell line which produces FSH under activin stimulation, we first tested whether subcutaneous xenografts of LßT2 cells resulted in tumour formation in Rag2KO mice. Histological analysis confirmed the presence of LßT2 tumours with endothelial cells and macrophages in their microenvironment. FSH expression was found in a subset of clusters of LßT2 cells in the tumours. We subsequently addressed the consequences of targeting activin signalling via injection of a soluble activin decoy receptor (sActRIIB-Fc). sActRIIB-Fc treatment resulted in significantly decreased LßT2 tumour volume. Reduced Smad2 phosphorylation as well as inhibition of tumour-induced FSH production confirmed the efficient targeting of activin-downstream signalling in treated tumours. More interestingly, treated tumours showed significantly fewer endothelial cells associated with reduced Vegfa expression. In vitro treatment of LßT2 cells with sActRIIB-Fc had no effect on cell proliferation or apoptosis, but Vegfa expression was inhibited, pointing to a likely paracrine effect of LßT2 cells on endothelial cells through activin-mediated Vegfa regulation. Further in vitro and in vivo studies are now needed to pinpoint the exact roles of activin signalling in these processes prior to translating these observations to the clinic.
Subject(s)
Gonadotrophs , Pituitary Neoplasms , Mice , Humans , Animals , Activins/metabolism , Gonadotrophs/metabolism , Pituitary Neoplasms/metabolism , Endothelial Cells/metabolism , Follicle Stimulating Hormone, beta Subunit/metabolism , Follicle Stimulating Hormone, beta Subunit/pharmacology , Follicle Stimulating Hormone/metabolism , Follicle Stimulating Hormone/pharmacology , Pituitary Gland/metabolism , Tumor MicroenvironmentABSTRACT
Objective: Registry data show that Cushing's syndrome (CS) and adrenal insufficiency (AI) increase mortality rates associated with infectious diseases. Little information is available on susceptibility to milder forms of infections, especially those not requiring hospitalization. This study aimed to investigate infectious diseases in patients with glucocorticoid disorders through the development of a specific tool. Methods: We developed and administered the InfeCtions in pAtients with endocRinOpathies (ICARO) questionnaire, addressing infectious events over a 12-month observation period, to 1017 outpatients referred to 4 University Hospitals. The ICARO questionnaire showed good test-retest reliability. The odds of infection (OR (95% CI)) were estimated after adjustment for confounders and collated into the ICARO score, reflecting the frequency and duration of infections. Results: In total, 780 patients met the inclusion criteria: 43 with CS, 32 with adrenal incidentaloma and mild autonomous cortisol secretion (MACS), and 135 with AI, plus 570 controls. Compared to controls, CS was associated with higher odds of urinary tract infections (UTIs) (5.1 (2.3-9.9)), mycoses (4.4 (2.1-8.8)), and flu (2.9 (1.4-5.8)). Patients with adrenal incidentaloma and MACS also showed an increased risk of UTIs (3.7 (1.7-8.0)) and flu (3.2 (1.5-6.9)). Post-dexamethasone cortisol levels correlated with the ICARO score in patients with CS. AI was associated with higher odds of UTIs (2.5 (1.6-3.9)), mycoses (2.3 (1.4-3.8)), and gastrointestinal infections (2.2 (1.5-3.3)), independently of any glucocorticoid replacement dose. Conclusions: The ICARO tool revealed a high prevalence of self-reported infections in patients with glucocorticoid disorders. ICARO is the first of its kind questionnaire, which could be a valuable tool for monitoring infections in various clinical settings.
Subject(s)
Adrenal Gland Neoplasms , Adrenal Insufficiency , Cushing Syndrome , Adrenal Gland Neoplasms/complications , Adrenal Insufficiency/complications , Adrenal Insufficiency/diagnosis , Adrenal Insufficiency/epidemiology , Cushing Syndrome/complications , Cushing Syndrome/diagnosis , Cushing Syndrome/epidemiology , Dexamethasone , Glucocorticoids/adverse effects , Humans , Hydrocortisone , Reproducibility of ResultsABSTRACT
Background: Aggressive and metastatic PitNETs are challenging conditions. Immune checkpoint inhibitors (ICIs) are currently considered in cases resistant to temozolomide (TMZ). However, clinical experience is essentially limited to case reports, with variable outcomes. Material and Methods: The effects of ICIs on 12 aggressive/metastatic PitNETs from the literature were reviewed and analyzed according to tumor characteristics, with the additional description of a silent-Pit1 metastatic tumor responding to pembrolizumab. Results: Most cases were metastatic (10/13: 6 corticotroph, 3 lactotroph, 1 silent Pit1); 3 were aggressive (2 corticotroph, 1 lactotroph). ICIS was used either as monotherapy or in combination. At last follow-up on ICI, a complete response (CR) was present in 3 cases and a partial response (PR) in 2 cases (4/5 metastatic). One sustained stable disease (SD) was reported. Progressive disease (PD) was observed in 7 cases, 3 of them after initial SD (n = 1) or PR (n = 3), with 2 reported deaths. PDL1 expression was studied in 10 cases and was high (>95%) in 2 Pit1-derived metastatic PitNETs (1 CR and 1 remarkable PR) but absent/low (<1%) in the remaining cases (including 1 CP and 2 PR). Elevated tumor mutation burden could be informative in corticotroph PitNETs, especially in mismatch repair-deficient tumors. Conclusion: Significant benefits from ICIs were documented in about half of TMZ-resistant PitNETS. High PDL1 expression was associated with remarkable responses but may be dispensable. Based on their acceptable tolerance and awaiting recognized predictors of response, ICIs may be considered a valuable option for such patients.
ABSTRACT
OBJECTIVES: The potential clinical effects of licorice (Glycyrrhiza spp.) and its extracts have been investigated since ancient times. Whether pseudohyperaldosteronism, with consequent arterial hypertension, is the only endocrine effect produced by licorice is uncertain, and a role in the reproductive system has been proposed. This review aimed to summarize the current knowledge on the pharmacologic effects of licorice on male and female reproductive systems. METHODS: Overall, 1462 records were extracted from electronic databases and systematically examined. A total of 28 studies were included in the final analysis. RESULTS: Preclinical and clinical studies revealed estrogen-like activity of licorice components, especially flavonoids, isoflavonoids, and chalcones, showing a potential role of licorice in ameliorating symptoms associated with estrogen insufficiency. Preclinical studies also showed weak antiandrogen properties and beneficial effects of licorice on gonadal function in both sexes, but clinical studies yield to poor and conflicting results depending on the type and dose of licorice. CONCLUSIONS: Licorice consumption can affect the reproductive system. However, its role needs to be further explored, especially due to the great variability of bioactive compounds used in existing studies.
Subject(s)
Glycyrrhiza , Triterpenes , Plant Extracts/pharmacology , Estrogens , Gonadal Steroid Hormones , GenitaliaABSTRACT
The pathogenesis of obesity and alterations in glucose profile have been linked to PRL excess, as it is reportedly associated with metabolic syndrome in thereabout one third of patients. In vitro exposure of pancreatic islet to PRL is known to stimulate insulin secretion and ß-cell proliferation, and in turn overexpression of PRL in ß-cells increases insulin release and ß-cell replication. PRL excess has been found to worsen glucose profile because it reduces glucose tolerance and induces insulin resistance either in obese and non-obese patients. To note, pancreatic ß-cells and adipocytes widely express dopamine receptors type 2, and dopamine has been hypothesized to play a key role as modulator of insulin and adipose functions. The dopamine agonists bromocriptine and cabergoline significantly improve abnormalities in glucose profile and reduce the prevalence of metabolic syndrome in a remarkable proportion of patients, regardless of whether body weight and PRL status may change. However, in men with hyperprolactinemia complicated by hypogonadism, testosterone replacement can ameliorate insulin resistance and abnormalities in glucose metabolism. Therefore, in patients with PRL-secreting pituitary adenomas control of PRL excess by dopamine agonists is mandatory to improve glucose and insulin abnormalities.
ABSTRACT
The discovery of dopamine inhibitory effects on prolactin secretion has led to an era of successful dopaminergic therapy for prolactinomas. Herein we provide an overview of the evolution of dopamine agonists and their use in patients with PRL-secreting pituitary tumors, starting from the 1970s up to today, highlighting that normalization of PRL levels, restoration of eugonadism, and reduction of tumor mass can be achieved in the majority of patients by treatment with dopamine agonists.
Subject(s)
Dopamine Agonists/therapeutic use , Pituitary Neoplasms/drug therapy , Prolactinoma/drug therapy , HumansABSTRACT
INTRODUCTION: Hyperprolactinaemia has been implicated in the pathogenesis of obesity and glucose intolerance and is reportedly associated with impaired metabolic profile and metabolic syndrome in approximately one third of patients. AREAS COVERED: Suppression of dopaminergic tone has been proposed as a potential mechanism responsible for weight gain and metabolic abnormalities in such patients. Dopamine receptor type 2 (D2R) is abundantly expressed on human pancreatic ß-cell and adipocytes, suggesting a regulatory role for peripheral dopamine in insulin and adipose functions. Medical treatment with the dopamine-agonists bromocriptine and cabergoline has been shown to significantly improve gluco-insulinemic and lipid profile, also reducing the prevalence of metabolic syndrome. In patients with concomitant hypogonadism, simultaneous correction of both PRL excess and testosterone deficiency is mandatory to improve insulin resistance and metabolic abnormalities. EXPERT COMMENTARY: Hyperprolactinemia promotes metabolic alterations. Control of PRL excess by dopamine agonists is mandatory to induce weight loss and to improve metabolic profile, and replacement treatment for concomitant hypogonadism effectively ameliorates insulin resistance and metabolic syndrome.