Effects of muscular strength training and growth hormone (GH) supplementation on femoral bone tissue: analysis by Raman spectroscopy, dual-energy X-ray absorptiometry, and mechanical resistance

The aim of the present study was to verify the effects of muscular strength training and growth hormone (GH) supplementation on femoral bone tissue by Raman spectroscopy (Raman), dual-energy X-ray absorptiometry (DXA), and mechanical resistance (F-max) analysis. A total of 40 male Wistar animals, 60 days old, were used. The animals were distributed into four groups: control (C), control with GH (GHC), muscular strength training (T), and muscular strength training with GH (GHT). Blood samples were collected for the quantification of creatine kinase (CK-MB) and the femurs were removed for analysis by Raman, DXA, and F-max. A more pronounced increase in the bone mineral components was verified in the T group, for all the variables obtained by the Raman (calcium, phosphate, amide, and collagen). In addition, for animals submitted to GH supplementation, there was a reduction in the variable bone mineral density (BMD) obtained by the DXA (p 0.05). It was concluded that animals that received GH supplementation demonstrated a decrease in BMD. In addition, T alone was able to promote increased calcium, phosphate, amide, and collagen compounds in bone tissue.35345354COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESSem informaçã

Interação entre células do cumulus e atividade da proteína quinase C em diferentes fases da maturação nuclear de oócitos bovinos Interaction between cumulus cells and the activity of protein kinase C at different stages of bovine oocyte nuclear maturation

Verificou-se a influência da proteína quinase C (PK-C) no reinício e na progressão da meiose em oócitos bovinos, determinando se as células do cumulus são mediadoras da PK-C na regulação da maturação dos oócitos. Complexos cumulus-oócitos (CCO) e oócitos desnudos (OD), distribuídos aleatoriamente em seis tratamentos (T) com base na presença de um ativador da PK-C (PMA) (T1 e T2), de um forbol éster incapaz de ativar a PK-C (4alfa-PDD-controle) (T3 e T4) ou de apenas o meio básico (TCM-199-controle) (T5 e T6), foram cultivados por 7, 9, 12, 18 e 22 horas. A percentagem de rompimento da vesícula germinativa no grupo cultivado com PMA foi maior do que nos dois grupos controle, com e sem células do cumulus. O cultivo de CCO e OD por 12 e 18 horas demonstrou que a PK-C influencia a progressão para os estádios de metáfase I (MI) e metáfase II (MII) de maneira dependente das células do cumulus. Nos períodos de 9 e 22 horas, não foi possível observar diferença entre os grupos quanto aos diferentes estádios de maturação. A ativação da PK-C acelera o reinício da meiose independentemente das células somáticas e acelera a progressão até os estádios de MI e MII na dependência das células do cumulus.<br>The aim of this study was to evaluate the effect of protein kinase C (PK-C) on the meiotic resumption and progression in bovine oocyte, and to determine if the cumulus cells mediate the PK-C action in the regulation of bovine oocyte nuclear maturation. Cumulus-oocyte complexes (COC) and denuded oocytes (DO), randomly allotted to 6 treatments (T) based on the presence of an activator of PK-C (PMA) (T1 and T2), or a phorbol ester unable to activate PK-C (4alphaPDD-control) (T3 and T4) or a basic culture medium (T5 and T6), were cultivated for 7, 9, 12, 18 and 22 hours. The percentage of germinal vesicle breakdown (GVBD) was higher when the oocytes were cultured with PMA than in the control groups with and without cumulus cells. However, PK-C was dependent of cumulus cells to affect the progression to the stages of metaphase I (MI) and metaphase II (MII) at 12 and 18 hours of culture. At 9 and 22 hours, no difference among groups was detected. PK-C accelerates the meiotic resumption independently of the somatic cells but depends on cumulus cells for the progression to the stages of MI and MII