Muscle protein metabolism in neonatal alloxan-administered rats: effects of continuous and intermittent swimming training

<p>Abstract</p> <p>Background</p> <p>This study aimed to examine the effects of intermittent and continuous swimming training on muscle protein metabolism in neonatal alloxan-administered rats.</p> <p>Methods</p> <p>Wistar rats were used and divided into six groups: sedentary alloxan (SA), sedentary control (SC), continuous trained alloxan (CA), intermittent trained alloxan (IA), continuous trained control (CC) and intermittent trained control (IC). Alloxan (250 mg/kg body weight) was injected into newborn rats at 6 days of age. The continuous training protocol consisted of 12 weeks of swimming training in individual cylinder tanks while supporting a load that was 5% of body weight; uninterrupted swimming for 1 h/day, five days a week. The intermittent training protocol consisted of 12 weeks of swimming training in individual cylinder tanks while supporting a load that was 15% of body weight; 30 s of activity interrupted by 30 s of rest for a total of 20 min/day, five days a week.</p> <p>Results</p> <p>At 28 days, the alloxan animals displayed higher glycemia after glucose overload than the control animals. No differences in insulinemia among the groups were detected. At 120 days, no differences in serum albumin and total protein among the groups were observed. Compared to the other groups, DNA concentrations were higher in the alloxan animals that were subjected to continuous training, whereas the DNA/protein ratio was higher in the alloxan animals that were subjected to intermittent training.</p> <p>Conclusion</p> <p>It was concluded that continuous and intermittent training sessions were effective in altering muscle growth by hyperplasia and hypertrophy, respectively, in alloxan-administered animals.</p

Effect of oat bran on time to exhaustion, glycogen content and serum cytokine profile following exhaustive exercise

The aim of this study was to evaluate the effect of oat bran supplementation on time to exhaustion, glycogen stores and cytokines in rats submitted to training. The animals were divided into 3 groups: sedentary control group (C), an exercise group that received a control chow (EX) and an exercise group that received a chow supplemented with oat bran (EX-O). Exercised groups were submitted to an eight weeks swimming training protocol. In the last training session, the animals performed exercise to exhaustion, (e.g. incapable to continue the exercise). After the euthanasia of the animals, blood, muscle and hepatic tissue were collected. Plasma cytokines and corticosterone were evaluated. Glycogen concentrations was measured in the soleus and gastrocnemius muscles, and liver. Glycogen synthetase-α gene expression was evaluated in the soleus muscle. Statistical analysis was performed using a factorial ANOVA. Time to exhaustion of the EX-O group was 20% higher (515 ± 3 minutes) when compared with EX group (425 ± 3 minutes) (p = 0.034). For hepatic glycogen, the EX-O group had a 67% higher concentrations when compared with EX (p = 0.022). In the soleus muscle, EX-O group presented a 59.4% higher glycogen concentrations when compared with EX group (p = 0.021). TNF-α was decreased, IL-6, IL-10 and corticosterone increased after exercise, and EX-O presented lower levels of IL-6, IL-10 and corticosterone levels in comparison with EX group. It was concluded that the chow rich in oat bran increase muscle and hepatic glycogen concentrations. The higher glycogen storage may improve endurance performance during training and competitions, and a lower post-exercise inflammatory response can accelerate recovery

Haematopoietic SCT in severe autoimmune diseases: updated guidelines of the European Group for Blood and Marrow Transplantation

In 1997, the first consensus guidelines for haematopoietic SCT (HSCT) in autoimmune diseases (ADs) were published, while an international coordinated clinical programme was launched. These guidelines provided broad principles for the field over the following decade and were accompanied by comprehensive data collection in the European Group for Blood and Marrow Transplantation (EBMT) AD Registry. Subsequently, retrospective analyses and prospective phase I/II studies generated evidence to support the feasibility, safety and efficacy of HSCT in several types of severe, treatment-resistant ADs, which became the basis for larger-scale phase II and III studies. In parallel, there has also been an era of immense progress in biological therapy in ADs. The aim of this document is to provide revised and updated guidelines for both the current application and future development of HSCT in ADs in relation to the benefits, risks and health economic considerations of other modern treatments. Patient safety considerations are central to guidance on patient selection and HSCT procedural aspects within appropriately experienced and Joint Accreditation Committee of International Society for Cellular Therapy and EBMT accredited centres. A need for prospective interventional and non-interventional studies, where feasible, along with systematic data reporting, in accordance with EBMT policies and procedures, is emphasized

Minimum blood lactate and muscle protein of rats during swimming exercise

Few studies dealing with effort intensity during swimming exercise in rats have been reported in the literature. Recently, with the use of the lactate minimum test (LMT), our group estimated the minimum blood lactate (MBL) of rats during swimming exercises. This information allowed accurate evaluation of the effort intensity developed by rats during swimming exercise. The present study was designed to evaluate the effects of swimming exercise sessions in below, equivalent and above intensities to MBL, on protein metabolism of rats. Adult (90 days) sedentary male Wistar rats were used in the present study. Mean values of MBL, in the present study, were obtained at blood concentration of 6.7±0.4 mmol/L with a load of 5% bw. The animals were sacrificed at rest (R) or immediately after a single swimming session (30 min) supporting loads below (3.5% bw), equivalent (5.0% bw) and high load (6.5% bw) to AT. Blood samples were collected each 5 min of exercise for lactate determination. Soleus muscle protein synthesis (amount of L-[14C] fenil alanyn incorporation to protein) and breakdown (tyrosin release) rates were evaluated. Blood lactate concentrations (mmol/L) stabilized with the below (5.4±0.01) and equivalent (6.4±0.006) to MBL but increased, progressively, with the high load. There were no differences in protein synthesis (pmol/mg.h) among rest values (65.2±3.4) and after-exercise supporting the loads below (61.5±1.3) and the equivalent (60.7±1.7) to MBL but there was a decrease with the high load (36.6±2.0). Protein breakdown rates (pmol/g.h) increase after exercise supporting the loads below (227.0±6.1), equivalent (227.9±6.0) and high (363.6±7.1) to MBL in relation to the rest (214.3±6.0). The results indicate the viability of the application of LMT in studies with rats since it detected alterations imposed by exercise

Immunological effects of interferon-alpha on chronic myelogenous leukemia

Treatment with interferon-alpha is effective for chronic myelogenous leukemia in the chronic phase (CML-CP), but the immunological mechanisms of the antileukemic effect of this substance are still unclear. The objective of this study was to investigate the immunological effects of interferon-alpha in CML patients. Markers of cellular activation and apoptosis, natural killer (NK) cell cytotoxicity and production of intracellular cytokines (IFN-gamma, IL-2 and IL-4) were determined by flow cytometry in the peripheral blood mononuclear cells (PBMC) of 26 CML-CP patients before and 3, 6 and 9 months after IFN-alpha treatment. The results were correlated with the hematological response. In the whole group of patients, INF-alpha use was followed by a significant increase of lymphocytes producing IL-2 and IFN-gamma, an increase in NK activity and a decrease in the number of CD34 + cells. Out of 26 CML patients, 15 achieved hematological remission and 7 achieved partial cytogenetic remission after 9 months of IFN-alpha treatment. There was an increase in the percentage of CD8/FasL + , DR/CD3 + , DQ/CD3 + , CD34/Fas + , DR/CD56 + , CD56/FasL + cells and of IFN-gamma- and IL-2-producing lymphocytes and an increase in NK cytotoxicity only in the group of patients who achieved complete hematological remission. Our results indicate that IFN-alpha use in CML-CP reduces the number of CD34 + cells, activates T cells, enhances stem cell apoptotic markers and increases the production of intracellular IFN-gamma and IL-2 by lymphocytes. Taken together, these results indicate that the therapeutic effect of IFN-alpha in CML-CP is mediated at least in part by immunological mechanisms.44122061206

Feed restriction and a diet's caloric value: The influence on the aerobic and anaerobic capacity of rats

<p>Abstract</p> <p>Background</p> <p>The influence of feed restriction and different diet's caloric value on the aerobic and anaerobic capacity is unclear in the literature. Thus, the objectives of this study were to determine the possible influences of two diets with different caloric values and the influence of feed restriction on the aerobic (anaerobic threshold: AT) and anaerobic (time to exhaustion: Tlim) variables measured by a lactate minimum test (LM) in rats.</p> <p>Methods</p> <p>We used 40 adult Wistar rats. The animals were divided into four groups: <it>ad libitum </it>commercial Purina^®diet (3028.0 Kcal/kg) (ALP), restricted commercial Purina^®diet (RAP), <it>ad libitum </it>semi-purified AIN-93 diet (3802.7 Kcal/kg) (ALD) and restricted semi-purified AIN-93 diet (RAD). The animals performed LM at the end of the experiment, 48 h before euthanasia. Comparisons between groups were performed by analysis of variance (p < 0,05).</p> <p>Results</p> <p>At the end of the experiment, the weights of the rats in the groups with the restricted diets were significantly lower than those in the groups with <it>ad libitum </it>diet intakes. In addition, the ALD group had higher amounts of adipose tissue. With respect to energetic substrates, the groups subjected to diet restriction had significantly higher levels of liver and muscle glycogen. There were no differences between the groups with respect to AT; however, the ALD group had lower lactatemia at the AT intensity and higher Tlim than the other groups.</p> <p>Conclusions</p> <p>We conclude that dietary restriction induces changes in energetic substrates and that <it>ad libitum </it>intake of a semi-purified AIN-93 diet results in an increase in adipose tissue, likely reducing the density of the animals in water and favouring their performance during the swimming exercises.</p