Aspectos neuroendócrinos da síndrome metabólica

Ivermectin does not interfere with seminal and hormonal parameters in male rabbits

Ivermectin (IVM) is a macrocyclic lactone used as a broad spectrum antiparasitic agent against nematodes and arthropods. It is mainly used in the control of parasitic infections of domestic animals, and recently has been used in humans to treat onchocerciasis, scabies, and pediculosis. In mammals, evidence has indicated that macrocyclic lactones interact with gamma-aminobutyric acid (GABA)-mediated chloride channels. The GABAergic system is known to be involved in the manifestation of sexual behavior, and previous studies have shown that IVM impaired sexual behavior in both male and female rats. Thus, considering that IVM may interfere with the sexual sphere, this study evaluated the temporal (1 up 60 days) effects of exposure to IVM (0.2 and 1.0 mg/kg, administered subcutaneously) on seminal and hormonal parameters of male rabbits. In male rabbits, the spermatozoa concentration, motility and morphology, the integrity of the plasmatic, acrosomal and mitochondrial membranes of the spermatozoa, the organ weights, gonadosomatic index, serum testosterone concentrations, histopathological findings were evaluated and hematological and serum biochemical analysis was conducted. No changes were observed in male seminal parameters evaluated by spermatozoa concentration, motility, and morphology, nor the potential for fertilization evaluated by the integrity of the plasmatic, acrosomal, and mitochondrial membranes of the spermatozoa; there was also no interference in serum testosterone concentration, serum biochemistry and hematological parameters. The findings of this study using the artificial vagina for collection of semen and computer-assisted semen analysis showed that IVM at doses of 0.2 and 1.0 mg/kg of SC did not alter any of the semen parameters of rabbits evaluated for up to 60 days after administration.

Evaluation of the hypothalamic-pituitary-adrenal axis in a case series of familial partial lipodystrophy

BACKGROUND

Familial partial lipodystrophy (FPL) is a rare genetic disease characterized by body fat abnormalities that lead to insulin resistance (IR). Clinical conditions linked to milder IR, such as type 2 diabetes (T2D) and metabolic syndrome, are associated with abnormalities of the hypothalamic-pituitary-adrenal (HPA) axis, but little is known about its activity in FPL.

METHODS

Patients meeting the clinical criteria for FPL were subjected to anthropometric, biochemical and hormone analyses. A genetic study to identify mutations in the genes encoding peroxisome proliferator-activated receptor gamma (PPARγ) was performed. Polycystic ovary syndrome and hepatic steatosis were investigated, and the patient body compositions were analyzed via dual X-ray energy absorptiometry (DXA). The HPA axis was assessed via basal [cortisol, adrenocorticotrophic hormone (ACTH), cortisol binding globulin, nocturnal salivary cortisol and urinary free cortisol (UFC)] as well as dynamic suppression tests (cortisol post 0.5 mg and post 1 mg dexamethasone).

RESULTS

Six patients (five female and one male) aged 17 to 42 years were included. In DXA analyses, the fat mass ratio between the trunk and lower limbs (FMR) was > 1.2 in all phenotypes. One patient had a confirmed mutation in the PPARγ gene: a novel heterozygous substitution of p. Arg 212 Trp (c.634C>T) at exon 5. HPA sensitivity to glucocorticoid feedback was preserved in all six patients, and a trend towards lower basal serum cortisol, serum ACTH and UFC values was observed.

CONCLUSIONS

Our findings suggest that FPL is not associated with overt abnormalities in the HPA axis, despite a trend towards low-normal basal cortisol and ACTH values and lower UFC levels. These findings suggest that the extreme insulin resistance occurring in FPL may lead to a decrease in HPA axis activity without changing its sensitivity to glucocorticoid feedback, in contrast to the abnormalities in HPA axis function in T2D and common metabolic syndrome.

Effect of Myoinositol and Antioxidants on Sperm Quality in Men with Metabolic Syndrome

This prospective longitudinal study investigated the effects of a dietary supplement in patients affected by reduced sperm motility (asthenospermic males) with metabolic syndrome. The product tested was Andrositol®, which contains myoinositol (MI) as principal compound, in association with other molecules, and the parameters evaluated were semen characteristics as well as hormone and metabolic profiles. The inclusion criteria were subjects aged over 18 years, with asthenospermia and metabolic syndrome. The exclusion criteria were presence of cryptorchidism, varicocele, and prostatitis. For this study, 45 males who had such features were enrolled. Their selection was made according to the 2010 World Health Organization (WHO) criteria (5th Edition) for the Evaluation of Human Semen. Hormone and metabolic profiles and semen parameters were assessed at the beginning of the study and after three months of treatment with Andrositol. The differences between the values before and after the supplementation were found statistically significant. Andrositol normalized the metabolic profile of these patients, improving their insulin sensitivity. Moreover, testosterone levels were increased and the semen characteristics, such as sperm concentration, motility, and morphology, highly improved. In conclusion, the association of MI with other molecules (micronutrients and vitamins) could be an effective therapy for metabolic disorders, as well as hormonal and spermatic changes responsible for male infertility.

Acute and chronic effects of resistance exercise on the testosterone and cortisol responses in obese males: a systematic review

The biosynthesis and metabolism of testosterone and cortisol are altered by the high levels of adipose tissue and the constant state of low-grade inflammation of obesity. Resistance exercise (REx) has become one of the main lifestyle interventions prescribed to obese individuals due to its ability to positively influence body composition and some biomarkers, such as cholesterol and insulin resistance. Yet, little research has been done in obese examining the effects of REx on the testosterone and blood cortisol responses, two integral hormones in both exercise and obesity. The obese testosterone response to REx and whether or not it is blunted compared to lean individuals remains elusive. Conflicting findings concerning the blood cortisol response have also been reported, likely due to variance in REx protocol and the level of obesity in the participants in studies. Comparatively, both of these hormones have been extremely well studied in untrained lean males, which could be used as a basis for future research in obese males. However, without this endocrinological information, it is unknown if the current acute REx prescriptions are appropriate for eliciting a favorable acute endocrinological response, and ultimately, a positive chronic adaptation in obese males.

High fat-induced obesity associated with insulin-resistance increases FGF-2 content and causes stromal hyperplasia in rat ventral prostate

Obesity affects sex hormone secretion, which can negatively influence prostatic structure, homeostasis, and disease. This investigation aimed to evaluate the repercussions of obesity induced by a high-fat diet on the rat prostate, with or without treatment with the aromatase inhibitor, Letrozole. Adult Wistar rats were fed a high-fat diet (20% saturated fat, O) for 15 weeks to induce obesity or received a balanced diet (4% fat, C). Then, a group of C and O rats were daily treated with Letrozole (1 mg/kg b.w. per day) for 2 weeks (CL and OL, respectively). Subsequently, ventral prostate was processed for analysis by transmission electron microscopy, immunohistochemistry, and Western blotting. Obesity decreased 70% of the testosterone plasma level. The prostate showed epithelial atrophy and dilated acini in the intermediate portion and epithelial wrinkling in the distal tips. The relative frequency of smooth muscle α-actin in the O group increased by 67%. Ultrastructurally, epithelial cells in obese animals presented altered secretory organelles, lipid droplets, and thicker subjacent fibromuscular layer. Letrozole treatment caused a partial restoration of the prostatic changes caused by obesity. Obesity increased the prostatic content of fibroblast growth factor-2 (FGF-2) by 150%, and Letrozole treatment increased this protein even more in the control and obese groups. This investigation shows that obesity provokes structural and ultrastructural changes in the epithelium of rat prostate; these changes might affect gland homeostasis and physiology. The epithelial and smooth muscle cell hyperplasia and increased FGF-2 expression observed in this experimental model of obesity/insulin-resistance might explain the high frequency of benign prostatic hyperplasia in insulin-resistant men.

Fatores associados à carga de doenças da síndrome metabólica entre adultos brasileiros

O objetivo deste trabalho é identificar fatores sociodemográficos e comportamentais associados à carga de doenças da síndrome metabólica, com base em dados coletados em 2007 pelo sistema de Vigilância de Fatores de Risco e Proteção para Doenças Crônicas por Inquérito Telefônico (VIGITEL). Foram avaliados 49.276 adultos, residentes nas capitais dos estados brasileiros e no Distrito Federal. Síndrome metabólica foi considerada na presença de pelo menos duas situações entre diabetes, dislipidemia, hipertensão arterial e obesidade. A carga de doença mostra que 22,7% da população adulta apresentam pelo menos uma das situações anteriormente descritas e 14,2% duas ou mais. As razões de prevalência ajustadas mostram que a probabilidade de síndrome metabólica é maior a partir dos 25 anos de idade, na atividade física insuficiente e na presença de excesso de peso nos dois sexos. Políticas públicas de promoção da saúde, que incorporem fatores modificáveis, que têm grande impacto na prevenção e tratamento da síndrome metabólica, devem ser estimuladas, bem como o diagnóstico clínico de populações de risco.

Relationship between insulin and hypogonadism in men with metabolic syndrome

OBJECTIVE

To evaluate the incidence of hypogonadism in men with metabolic syndrome and its correlation with serum insulin levels.

METHODS

Observational, transversal study with 80 men with metabolic syndrome. The individuals were divided into two groups: Group 1: 56 patients (70%) with total testosterone > 300 ng/dL (normal gonadal function); Group 2: 24 patients (30%) with total testosterone < 300 ng/dL (hypogonadic).

RESULTS

The subjects from Group 2 compared to Group 1 presented higher body mass index (BMI), waist and hip circumferences, insulin, homeostasis model assessment insulin resistance index (Homa-IR) and beta cell (Homa-beta), and triglycerides, but lower SHBG and free testosterone values. Inverse correlations between insulin levels and total testosterone and SHBG, as well as between Homa-IR and total testosterone were observed.

CONCLUSION

In this series of men with metabolic syndrome, hypogonadism was associated with insulin resistance and may be a marker of metabolic abnormalities.

O fazer do cuidador familiar: significados e crenças

Este estudo de natureza qualitativa tem por objetivo apreender significados e crenças de cuidadores de portadores da Síndrome Metabólica no contexto domiciliar. Utilizou-se o Interacionismo Simbólico como referencial teórico, seguindo-se as recomendações de Bardin (1977) para a análise de conteúdo. Foram utilizadas a entrevista semi-estruturada e a observação livre para a coleta de dados, no período de março a maio de 2005. Os resultados mostraram importante sobrecarga de trabalho dispensada ao familiar pelo cuidador, a qual implica em significante impacto sobre sua saúde física, emocional e social. Conclui-se que as reflexões acerca de pessoas que cuidam continuamente de seus familiares devam ser intensificadas, com vistas a uma melhor preparação das mesmas para o acompanhamento terapêutico domiciliar.

Increased diagnostic probability of subclinical cushing’s syndrome in a population sample of overweight adult patients with type 2 diabetes mellitus

Endogenous Cushing’s Syndrome (CS) is unusual. Patients with subclinical CS (SCS) present altered cortisol dynamics without obvious manifestations. CS occurs in 2-3% of obese poorly controlled diabetics. We studied 103 overweight adult outpatients with type 2 diabetes to examine for cortisol abnormalities and SCS. All collected salivary cortisol at 23:00 h and salivary and serum cortisol after a 1 mg dexamethasone suppression test (DST). Patients whose results were in the upper quintile for each test (253 ng/dL, 47 ng/dL, and 1.8 mg/dL, respectively for the 23:00 h and post-DST saliva and serum cortisol) were re-investigated. Average values from the upper quintile group were 2.5-fold higher than in the remaining patients. After a confirmatory 2 mg x 2 day DST the investigation for CS was ended for 61 patients with all normal tests and 33 with only one (false) positive test. All 8 patients who had two abnormal tests had subsequent normal 24h-urinary cortisol, and 3 of them were likely to have SCS (abnormal cortisol tests and positive imaging). However, a final diagnosis could not to be confirmed by surgery or pathology. Although not confirmatory, the results of this study suggest that the prevalence of SCS is considerably higher in populations at risk than in the general population.

Prevalência de síndrome metabólica em estudo de base populacional, Vitória, ES - Brasil

Síndrome Metabólica (SM) é um transtorno representado pela agregação de fatores predisponentes para desenvolvimento de doenças cardiovasculares e diabetes. Apesar da importância da SM, há carência de dados sobre as características epidemiológicas desta condição na população brasileira. Determinamos a prevalência da SM por sexo, faixa etária e nível socioeconômico na população da cidade de Vitória, ES, Brasil, utilizando os critérios do NCEP/ATPIII. Foram coletados dados socioeconômicos, bioquímicos, antropométricos e hemodinâmicos em 1.663 indivíduos de amostra randômica da população (25-64 anos) de Vitória. A prevalência foi de 29,8% (IC95 = 28-32%), sem diferença entre sexos. De 25 a 34 anos, a prevalência foi 15,8%, alcançando 48,3% na faixa de 55 a 64 anos. Verificou-se aumento progressivo de prevalência em mulheres do maior para o menor nível socioeconômico. O parâmetro da SM mais freqüente em homens foi hipertensão, seguido de hipertrigliceridemia, baixo HDL-colesterol, hiperglicemia e obesidade abdominal. Nas mulheres, hipertensão em primeiro lugar, seguida do baixo HDL-colesterol, obesidade abdominal, hipertrigliceridemia e hiperglicemia. Conclui-se que a prevalência de SM é elevada, inclusive nos mais jovens, com grande contribuição da hipertensão para o seu diagnóstico. Controle dos fatores de risco deve ser promovido visando reduzir o impacto das doenças cardiovasculares na mortalidade geral.

Prevalence of the metabolic syndrome and its components in Brazilian women with polycystic ovary syndrome

OBJECTIVE

To determine the prevalence of the metabolic syndrome (MetS) and its components in Brazilian women with polycystic ovary syndrome (PCOS).

DESIGN

Cross-sectional study.

SETTING

University Hospital, Federal University of Rio Grande do Norte, Natal-RN, Brazil.

PATIENT(S)

102 women with PCOS by the Rotterdam consensus criteria.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Clinical and biochemical parameters for MetS as defined by the National Cholesterol Education Program Adult Treatment Panel (NCEP ATP III).

RESULT(S)

The prevalence for individual components of MetS were high-density lipoprotein cholesterol level <50 mg/dL in 69.6%, waist circumference >or=88 cm in 57.9%, triglyceride level >or=150 mg/dL in 31.7%, blood pressure >or=130/85 mm Hg in 18.6%, and fasting glucose concentrations >or=110 mg/dL in 2.9%. Three or more of these individual criteria were present in 29 (28.4%) of the patients. The prevalence of MetS increased with body mass index: 3.2%, 19.2% and 52.3% for normal, overweight, and obese women, respectively.

CONCLUSION(S)

These findings indicate that Brazilian women with PCOS have a high prevalence of MetS and its individual components, particularly a decreased high-density lipoprotein cholesterol level. Thus, these women are at increased risk of diabetes mellitus and cardiovascular disease.