Thiol/disulfide status regulates the activity of thiol-containing kinases related to energy homeostasis in rat kidney

ABSTRACT Considering that thiol-containing enzymes like kinases are critical for several metabolic pathways and energy homeostasis, we investigated the effects of cystine dimethyl ester and/or cysteamine administration on kinases crucial for energy metabolism in the kidney of Wistar rats. Animals were injected twice a day with 1.6 µmol/g body weight cystine dimethyl ester and/or 0.26 µmol/g body weight cysteamine from the 16th to the 20th postpartum day and euthanized after 12 hours. Pyruvate kinase, adenylate kinase, creatine kinase activities and thiol/disulfide ratio were determined. Cystine dimethyl ester administration reduced thiol/disulfide ratio and inhibited the kinases activities. Cysteamine administration increased the thiol/disulfide ratio and co-administration with cystine dimethyl ester prevented the inhibition of the enzymes. Regression between the thiol/disulfide ratio, and the kinases activities were significant. These results suggest that redox status may regulate energy metabolism in the rat kidney. If thiol-containing enzymes inhibition and oxidative stress occur in patients with cystinosis, it is possible that lysosomal cystine depletion may not be the only beneficial effect of cysteamine administration, but also its antioxidant and thiol-protector effect.

Prevalência do uso de agentes anabólicos em praticantes de musculação de Porto Alegre / Prevalence of the use of anabolic agents among strength training apprentices in Porto Alegre, RS

Este estudo procura determinar, através de questionário realizado por entrevistadores, a prevalência do uso atual ou passado de esteróides anabólicos androgênicos (EAA), outros hormônios (OH), outros medicamentos (OM) e outras substâncias (suplementos alimentares e drogas ilícitas) em praticantes de musculação da cidade de Porto Alegre, entrevistando 288 indivíduos sorteados de uma amostra de 13 academias. A prevalência observada foi de 11,1 por cento (32/288) para EAA, 5,2 por cento (16/288) para OH e 4,2 por cento (12/288) para OM. Os EAA mais usados foram decanoato de nandrolona e estanozolol. Os OH foram gonadotrofina coriônica humana, triiodotironina e OM como lipostabil, diuréticos e medicamentos veterinários (ex.: Monovin E). Os efeitos colaterais mais freqüentes foram comportamentais (variação de humor, irritabilidade e agressividade) e endócrinos (acne e aumento/ diminuição da libido). Quando analisados os EAA juntamente aos OH na variável denominada "agentes hormonais" (AH), observamos diferença estatística (p< 0,05) entre os sexos, sendo o uso de AH mais prevalente em homens e entre os consumidores de suplementos alimentares. Comparar este estudo a outros é difícil, pois existe diferença no desenho epidemiológico. Entretanto, a alta prevalência observada sugere a necessidade de medidas preventivas, educativas e de cuidados na assistência desta população.

This study aimed to determine through a questionnaire applied to interviewers, the current or past use of anabolic androgenic steroids (AAS), as well as other hormones (OH), and other medicines (OM), food supplement and illicit drugs among strength training apprentices in the city of Porto Alegre, RS. We interviewed 288 subjects draw from a sample of 13 gyms. The prevalence of current and past use of AAS was about 11.1 percent (32/288), OH 5.2 percent (16/288) and OM 4.2 percent (12/288). The most used AAS were nandrolone and stanozolol; the OH were gonadotropin, triiodothyronine (T3) and OM, like lipostabil, diuretics and veterinary medicines (Monovin E). The most frequent side-effects were behavioral such as humor oscillation, irritability and hostility, and endocrine disturbances such as acne and increased or decreased libido. When analyzed together with other hormones in a variable named "hormonal agents" (AH), AAS presented a statistical difference (p< 0.05) among genders considering that the most frequent use of AH occurred among men and those who consume food supplements. The comparison of these findings to other national and international results is difficult due to the epidemiological design. Even if it is considered, the observed prevalence suggests that preventive attitudes as well as special care in the orientation and education of this population must be taken.