Beta-Blocker Type Effect on Substrate Oxidation during HIIE in Heart Failure Patients: Pilot Data / Efeito do Tipo Betabloqueador na Oxidação de Substratos durante HIIE em Pacientes com Insuficiência Cardíaca: Dados Piloto

Abstract The effect of third and second-generation type of beta-blocker on substrate oxidation especially during high-intensity exercises are scarce. The objective of the study is to explore differences of beta-blocker regimens (vasodilating vs. non-vasodilating beta-blockers) for substrate oxidation during in high-intensity intermittent exercise (HIIE) in chronic heart failure and reduced ejection fraction (HFrEF). Eighteen CHF males (58.8 ± 9 years), 8 under use of β1 specific beta-blockers+alfa 1-blocker and 10 using β1 non-specific beta-blockers, were randomly assigned to 4 different HIIE, in a cross-over design. The 4 protocols were: 30 seconds (A and B) or 90 seconds (C and D) at 100% peak power output, with passive (A and C) or active recovery (50% of PPO; B and D). Energy expenditure (EE; kcal/min), quantitative carbohydrate (CHO) and lipid oxidation (g/min) and qualitative (%) contribution were calculated. Two-way ANOVA and Bonferroni post-hoc test were used (p-value ≤ 0.05) to compare CHO and lipid oxidation at rest and at 10min. Total exercise time or EE did not show differences for beta-blocker use. The type of beta-blocker use showed impact in CHO (%) and lipid (g/min and %) for rest and 10 min, but absolute contribution of CHO (g/min) was different just at 10min (Interaction p = 0.029). Higher CHO oxidation was found in vasodilating beta-blockers when comparing to non-vasodilating. According to our pilot data, there is an effect of beta-blocker type on substrate oxidation during HIIE, but no influence on EE or exercise total time in HFrEF patients.

Resumo Os dados sobre efeito do tipo de betabloqueador de terceira e segunda geração na oxidação do substrato, especialmente durante exercícios de alta intensidade, são escassos. O objetivo do estudo é explorar as diferenças de tratamentos com betabloqueadores (betabloqueadores vasodilatadores vs. não-vasodilatadores) na oxidação de substratos durante exercícios intermitentes de alta intensidade (HIIE) na insuficiência cardíaca crônica e fração de ejeção do ventrículo esquerdo reduzida (ICFEr). Dezoito pacientes do sexo masculino com ICC (58,8 ± 9 anos), 8 em uso de betabloqueadores β1 específicos + bloqueador α-1 e 10 utilizando betabloqueadores β1 não-específicos, foram aleatoriamente designados para 4 diferentes HIIE, em um desenho cruzado. Os 4 protocolos foram: 30 segundos (A e B) ou 90 segundos (C e D) a 100% da potência de pico de saída (PPO), com recuperação passiva (A e C) ou ativa (50% de PPO; B e D). O gasto energético (GE; kcal/min), a ingestão de carboidratos quantitativos (CHO) e oxidação lipídica (g/min) e qualitativa (%) foram calculados. Anova de dois fatores e teste post-hoc de Bonferroni foram usados (p-valor ≤ 0,05) para comparar a oxidação de CHO e lipídios em repouso e aos 10 minutos. O tempo total de exercício ou GE não mostraram diferenças de acordo com o uso de betabloqueadores. O tipo de betabloqueador mostrou impacto em CHO (%) e lípides (g/min e %) para repouso e aos 10 min, mas a contribuição absoluta de CHO (g/min) foi diferente apenas aos 10 minutos (Interação p = 0,029). Foram encontradas maiores oxidações de CHO com betabloqueadores vasodilatadores quando comparados com os não-vasodilatadores. De acordo com nossos dados piloto, há um efeito do tipo do betabloqueador na oxidação do substrato durante o HIIE, mas nenhuma influência no GE ou no tempo total de exercício nos pacientes com ICFEr.

Effect of pre-exercise carbohydrate availability on fat oxidation and energy expenditure after a high-intensity exercise

The aim of this study was to test the hypothesis that reduced pre-exercise carbohydrate (CHO) availability potentiates fat oxidation after an exhaustive high-intensity exercise bout. Eight physically active men underwent a high-intensity exercise (∼95% V̇O2max) until exhaustion under low or high pre-exercise CHO availability. The protocol to manipulate pre-exercise CHO availability consisted of a 90-min cycling bout at ∼70% V̇O2max + 6 × 1-min at 125% V̇O2max with 1-min rest, followed by 48 h under a low- (10% CHO, low-CHO availability) or high-CHO diet (80% CHO, high-CHO availability). Time to exhaustion was shorter and energy expenditure (EE) lower during the high-intensity exercise in low- compared to high-CHO availability (8.6±0.8 and 11.4±1.6 min, and 499±209 and 677±343 kJ, respectively, P<0.05). Post-exercise EE was similar between low- and high-CHO availability (425±147 and 348±54 kJ, respectively, P>0.05), but post-exercise fat oxidation was significantly higher (P<0.05) in low- (7,830±1,864 mg) than in high-CHO availability (6,264±1,763 mg). The total EE (i.e., exercise EE plus post-exercise EE) was similar between low- and high-CHO availability (924±264 and 1,026±340 kJ, respectively, P>0.05). These results suggest that a single bout of high-intensity exercise performed under low-CHO availability increased post-exercise fat oxidation, and even with shorter exercise duration, both post-exercise EE and total EE were not impaired.

Soluble carbohydrate content variation in Sanionia uncinata and Polytrichastrum alpinum, two Antarctic mosses with contrasting desiccation capacities

BACKGROUND: Cryptogamic vegetation dominates the ice-free areas along the Antarctic Peninsula. The two mosses Sanionia uncinata and Polytrichastrum alpinum inhabit soils with contrasting water availability. Sanionia uncinata grows in soil with continuous water supply, while P. alpinum grows in sandy, non-flooded soils. Desiccation and rehydration experiments were carried out to test for differences in the rate of water loss and uptake, with non-structural carbohydrates analysed to test their role in these processes. RESULTS: Individual plants of S. uncinata lost water 60 % faster than P. alpinum; however, clumps of S. uncinata took longer to dry than those of P. alpinum (11 vs. 5 h, respectively). In contrast, rehydration took less than 10 min for both mosses. Total non-structural carbohydrate content was higher in P. alpinum than in S. uncinata, but sugar levels changed more in P. alpinum during desiccation and rehydration (60-50 %) when compared to S. uncinata. We report the presence of galactinol (a precursor of the raffinose family) for the first time in P. alpinum. Galactinol was present at higher amounts than all other non-structural sugars. CONCLUSIONS: Individual plants of S. uncinata were not able to retain water for long periods but by growing and forming carpets, this species can retain water the longest. In contrast individual P. alpinum plants required more time to lose water than S. uncinata, but as moss cushions they suffered desiccation faster than the later. On the other hand, both species rehydrated very quickly. We found that when both mosses lost 50 % of their water, carbohydrates content remained stable and the plants did not accumulate non-structural carbohydrates during the desiccation prosses as usually occurs in vascular plants. The raffinose family oligosaccarides decreased during desiccation, and increased during rehydration, suggesting they function as osmoprotectors.

Proteomic analysis of the regenerating liver following 2/3 partial hepatectomy in rats

BACKGROUND: Liver regeneration (LR) after 2/3 partial hepatectomy (PH) is one of the most studied models of cell, organ, and tissue regeneration. Although the transcriptional profile analysis of regenerating liver has been carried out by many reserachers, the dynamic protein expression profile during LR has been rarely reported up to date. Therefore, this study aims to detect the global proteomic profile of the regenerating rat liver following 2/3 hepatectomy, thereby gaining some insights into hepatic regeneration mechanism. RESULTS: Protein samples extracted from the sham-operated and the regenerating rat livers at 6, 12, 24, 72, 120 and 168 h after PH were separated by IEF/SDS-PAGE and then analyzed by MALDI-TOF/TOF mass spectrometry. Compared to sham-operated groups, there were totally 220 differentially expressed proteins (including 156 up-regulated, 62 down-regulated, and 2 up/down-regulated ones) identified in the regenerating rat livers, and most of them have not been previously related to liver regeneration. According to the expression pattern analysis combined with gene functional analysis, it showed that lipid and carbohydrate metabolism were enhanced at the early phase of LR and continue throughout the regeneration process. Ingenuity Pathway Analysis indicated that YWHAE protein (one of members of the 14-3-3 protein family) was located at the center of pathway networks at all the timepoints after 2/3 hepatectomy under our experimental conditions, maybe suggesting a central role of this protein in regulating liver regeneration. Additionally, we also revealed the role of Cdc42 (cell division cycle 42) in the termination of LR. CONCLUSIONS: For the first time, our proteomic analysis suggested an important role of YWHAE and pathway mediated by this protein in liver regeneration, which might be helpful in expanding our understanding of LR amd unraveling the mechanisms of LR.

Prediabetes y diabetes gestacional / Prediabetes and gestational diabetes

Se debe considerar a la diabetes gestacional (DG) como toda intolerancia a los carbohidratos que aparece o se reconoce durante el embarazo, independientemente del momento de la gestación al diagnóstico del trastorno metabólico, si se administra o no insulina, o si desaparece o no después del parto. Por ello, resulta un grupo heterogéneo de situaciones con diferentes expectativas y pronósticos, en dependencia del momento de su presentación y del grado de afectación metabólica que manifieste...(AU)

Aspectos epidemiológicos de la prediabetes, diagnóstico y clasificación / Epidemiological characteristics of prediabetes, diagnosis and classification

La creciente prevalencia y progresión de la prediabetes a la diabetes (DM) ha convertido a la morbilidad y la mortalidad relacionadas con ella en un problema importante de salud pública. Los diabéticos son vulnerables a complicaciones múltiples y complejas (cardiopatía, accidente cerebrovascular, arteriopatía periférica y microangiopatía entre otras). Las evidencias epidemiológicas indican que esas complicaciones comienzan ya antes de que los pacientes hayan llegado al estadio de diabetes manifiesta. La intervención en los cambios en el estilo de vida sobre las personas en etapas de prediabetes, tiene el potencial de reducir la incidencia de diabetes y la enfermedad cardiovascular y microvascular relacionadas. el término prediabetes se aplica a aquellos casos en los que los niveles de glucemia se encuentran por encima de los valores para individuos normales, pero por debajo de los niveles considerados para DM. Dada su alta frecuencia resulta conveniente considerar la prediabetes como un estado de riesgo importante para la predicción de diabetes y de complicaciones vasculares, así como una manifestación subclínica de un trastorno del metabolismo de los carbohidratos(AU)

Effect of carbohydrate availability on time to exhaustion in exercise performed at two different intensities

This study examined the effects of pre-exercise carbohydrate availability on the time to exhaustion for moderate and heavy exercise. Seven men participated in a randomized order in two diet and exercise regimens each lasting 3 days with a 1-week interval for washout. The tests were performed at 50 percent of the difference between the first (LT1) and second (LT2) lactate breakpoint for moderate exercise (below LT2) and at 25 percent of the difference between the maximal load and LT2 for heavy exercise (above LT2) until exhaustion. Forty-eight hours before each experimental session, subjects performed a 90-min cycling exercise followed by 5-min rest periods and a subsequent 1-min cycling bout at 125 percent VO2max/1-min rest periods until exhaustion to deplete muscle glycogen. A diet providing 10 percent (CHOlow) or 65 percent (CHOmod) energy as carbohydrates was consumed for 2 days until the day of the experimental test. In the exercise below LT2, time to exhaustion did not differ between the CHOmod and the CHOlow diets (57.22 ± 24.24 vs 57.16 ± 25.24 min). In the exercise above LT2, time to exhaustion decreased significantly from 23.16 ± 8.76 min on the CHOmod diet to 18.30 ± 5.86 min on the CHOlow diet (P < 0.05). The rate of carbohydrate oxidation, respiratory exchange ratio and blood lactate concentration were reduced for CHOlow only during exercise above LT2. These results suggest that muscle glycogen depletion followed by a period of a low carbohydrate diet impairs high-intensity exercise performance.

Body composition alterarions, energy expenditure and fat oxidation in elderly males suffering from prostate cancer, pre and post orchiectomy

INTRODUCTION: Testosterone is needed for normal male development, muscle strength, bone mineralization, hematopoietic function, and sexual and reproductive functions. The main purpose of androgen deprivation therapy in prostate cancer is to reduce tumor progression, but therapy is often accompanied by significant adverse effects. OBJECTIVE: This study aimed to determine the effects of androgen deprivation therapy on body composition and resting metabolic rate in patients with prostate cancer. PATIENTS AND METHODS: A prospective study was performed to evaluate the body composition of 16 elderly males (aged 63-96; median age 71) with prostate cancer scheduled for orchiectomy, one year before and after surgery. Body composition was measured by DEXA, and energy expenditure, fat and carbohydrate oxidation were measured by indirect calorimetry. RESULTS: Body weight (p=0.01), lean mass (p=0.004), and lipid oxidation (p=0.001) decreased significantly. Carbohydrate oxidation (p=0.02), FSH (p=0.0001) and LH (p=0.0001) levels increased significantly. Changes in fat mass (p=0.06) and bone mineral density (p=0.48) were not significant. CONCLUSIONS: After 12 months of androgen deprivation therapy, elderly men with metastatic prostate cancer exhibit a decline in lean body mass and lipid oxidation, together with increased carbohydrate oxidation.

Insulinemia, ingesta alimentaria y metabolismo energético / Insulinemia, food intake and energy metabolism

Insulin is an anabolic hormone involved in the control of food intake and energy metabolism. Its secretion is mainly stimulated after the rise of glycemia in response to carbohydrate intake. However, this hormone is also secreted after the ingestion of protein and fat. High-fat diets results in lesser insulin levels, with consequent increase in hunger and prospective desire for food ingestion, favoring weight gain. Moreover, the ingestion of such diets results in an increase of fat oxidation, favoring the reduction of energy metabolism and consequently weight gain. Protein ingestion, separately, seems not to exert significant changes in the glycemic response. To understand the metabolic answers unchained by the ingestion of the different macronutrients is important to elucidate corporal weight modifications and the insulin resistance mechanism.

La insulina es una hormona de carácter anabólico relacionada con el control de la ingesta alimentaria y del metabolismo energético. Su secreción es estimulada, especialmente por la elevación de la glicemia en respuesta a la ingesta de carbohidratos. Sin embargo, esta hormona también es secretada tras la ingesta de proteínas y de lípidos. Dietas ricas en lípidos se traducen en menores niveles séricos de insulina, con un consecuente aumento en la puntuación de la sensación de hambre y del deseo prospectivo de ingerir de alimentos, favoreciendo la ganancia de peso. Además, la ingesta de tales dietas dan como resultado el aumento de la oxidación de lípidos, favoreciendo la reducción del metabolismo energético y consecuentemente de la ganancia de peso. La ingesta de proteínas, aisladamente, parece no ejercer cambios significativos en la respuesta glicémica. Comprender las respuestas metabólicas desencadenadas por la ingesta de los diferentes macronutrientes es de fundamental importancia para aclarar las modificaciones del peso corporal y del mecanismo de resistencia insulínica.

Effect of water deficit on carbohydrate status and enzymes of carbohydrate metabolism in seedlings of wheat cultivars.

The effect of water deficit on carbohydrate status and enzymes of carbohydrate metabolism (alpha and beta amylases, sucrose phosphate synthase, sucrose synthase, acid and alkaline invertases) in wheat (Triticum aestivum L.) was investigated in the seedlings of drought-sensitive (PBW 343) and drought-tolerant (C 306) cultivars. The water deficit was induced by adding 6% mannitol (water potential -0.815 Mpa) in the growth medium. The water deficit reduced starch content in the shoots of tolerant seedlings as compared to the sensitive ones, but increased sucrose content in the shoots and roots of tolerant seedlings, indicating their protective role during stress conditions. It also decreased the alpha-amylase activity in the endosperm of seedlings of both the cultivars, but increased alpha and beta amylase activities in the shoots of tolerant ones. Sucrose phosphate synthase (SPS) activity showed a significant increase at 6 days of seedling growth (DSG) in the shoots of stressed seedlings of tolerant cultivar. However, SPS activity in the roots of stressed seedlings of sensitive cultivar was very low at 4 DSG and appeared significantly only at day 6. Sucrose synthase (SS) activity was lower in the shoots and roots of stressed seedlings of tolerant cultivar than sensitive ones at early stage of seedling growth. Higher acid invertase activity in the shoots of seedlings of tolerant cultivar appeared to be a unique characteristic of this cultivar for stress tolerance. Alkaline invertase activity, although affected under water deficit conditions, but was too low as compared to acid invertase activity to cause any significant affect on sucrose hydrolysis. In conclusion, higher sucrose content with high SPS and low acid invertase and SS activities in the roots under water deficit conditions could be responsible for drought tolerance of C 306.

Composição corporal: influência na ação da insulina, leptina, lipase lipoprotéica e lipase hormônio-sensível / Body composition: influence on insulin action, leptin, lipoproteic-and hormone-sensitive lipase

The balance between food intake and energy expenditure is of major importance for weight control and prevention of non-transmissible diseases. Within this context body composition profile is a determining factor for the adequate functioning of neuroendocrine mechanisms; body fat, especially that localized around the abdomen, plays a major role in these mechanisms. Fat tissue may be considered an endocrine organ since hormones such as insulin and leptin, are directly linked to its storage acting in the control of food intake, energy expenditure and nutrient metabolism. In addition, enzymes such as lipoproteic- and hormone-sensitive lipase, which are directly related to lipid metabolism, are regulated by several hormones, including insulin, which in turn are influenced by fat storages. Usually, alteration of these enzymes trigger important metabolic changes, such as elevated serum tryglicerides, which is involved with onset of diabetes and dislipidemia. Considering the influence of body composition on the body's functioning itis essential to stimulate the practice of regular physical activity and incorporation of adequate feeding habits and life style, since these could contribute to a better body composition profile. Moreover, with relatively simple and inexpensive anthropometric measurements it is possible to detect high percentage of body fat, and by means of appropriate interventions, prevent and control many non-transmissible diseases

El equilibrio entre la ingestión alimentar y elgasto de energía es de importancia fundamental para el control del peso y prevención de las enfermedades crónico-degenerativas. En esse contexto, la composición corpórea es un fator determinante en el funcionamiento correcto delos mecanismos neuroendocrinos, y la grasa corpórea, principalmente aquella localizada enel área abdominal, ejerce gran influencia en esos mecanismos.El tejido adiposo puede ser considerado un órganoendocrino, porque se relacionan hormonas, como insulina y leptina, directamente al tamaño de su depósito y ellos actúan en el control de la ingesta alimentar, en el gasto de energía y en el metabolismo de los nutrientes. Además, enzimas como las lipoprotéica, lipasa y lipasa sensible a hormona que participan directamente en el metabolismo de lípidos tiene su actividad controlada por varias hormonas, como la insulina que es fuertemente influenciada por los depósitos de grasa corpórea existentes. Normalmente, la alteración de esas enzimas desencadena alteraciones metabólicas importantes como la elevación de los niveles séricos de triglicéridos,involucrados principalmente en el aparecimiento de diabetes y dislipidemias.Considerando que la influencia de la composición corpórea en el funcionamiento del organismo semanifiesta la importancia del incentivo de la práctica de actividad física de una manera regulary la adopción de hábitos alimentarios y de estilo devida adecuados. Esto contribuiría a un mejor perfil de la composición corpórea. Además, por médio de medidas antropométricas relativamente simples y de bajo costo es posible descubrir los porcentajes elevados de grasa corpórea y a través de las intervenciones prevenir y controlar muchas de las enfermedades crónico-degenerativas.

O equilíbrio entre a ingestão alimentar e o gasto energético é de fundamental importância para o controle do peso e prevenção de doenças não transmissíveis. Nesse contexto, o padrão de composição corporal é fator determinante no funcionamento adequado dos mecanismos neuro-endócrinos, sendo que a gordura corporal, principalmente a localizada na região abdominal, exerce grande influência nesses mecanismos. O tecido adiposo pode ser considerado um órgão endócrino, visto que hormônios, como insulina e leptina, estão diretamente ligados ao tamanho do seu estoque e atuam no controle da ingestão alimentar, gasto energético e metabolismo dos nutrientes. Além disso, enzimas como lipase lipoprotéica e lipase hormônio sensível, as quais estão envolvidas diretamente no metabolismo de lipídios, têm sua atividade controlada por diversos hormônios, como a insulina, que por sua vez sofrem grande influência dos estoques de gordura corporal. Normalmente, a alteração dessas enzimas desencadeia alterações metabólicas importantes como a elevação dos níveis séricos de triglicerídeos, envolvidos principalmente no aparecimento de diabetes e dislipidemias. Considerando essa influência da composição corporal sobre o funcionamento do organismo torna-se importante o incentivo à prática da atividade física, de forma regular, e a adoção de hábitos alimentares e de estilo de vida adequados, já que isto contribuiria para um melhor perfil da composição corporal. Além disso, por meio de medidas antropométricas ,relativamente simples e de baixo custo, é possível detectar elevados percentuais de gordura corporal e por meio de intervenções, prevenir e controlar muitas das doenças não transmissíveis