Exercise and Sirtuins: A Way to Mitochondrial Health in Skeletal Muscle

The sirtuins form a family of evolutionarily conserved nicotinamide adenine dinucleotide (NAD)-dependent deacetylases. Seven sirtuins (SIRT1–SIRT7) have been described in mammals, with specific intracellular localization and biological functions associated with mitochondrial energy homeostasis, antioxidant activity, proliferation and DNA repair. Physical exercise affects the expression of sirtuin in skeletal muscle, regulating changes in mitochondrial biogenesis, oxidative metabolism and the cellular antioxidant system. In this context, sirtuin 1 and sirtuin 3 have been the most studied. This review focuses on the effects of different types of exercise on these sirtuins, the molecular pathways involved and the biological effect that is caused mainly in healthy subjects. The reported findings suggest that an acute load of exercise activates SIRT1, which in turn activates biogenesis and mitochondrial oxidative capacity. Additionally, several sessions of exercise (training) activates SIRT1 and also SIRT3 that, together with the biogenesis and mitochondrial oxidative function, jointly activate ATP production and the mitochondrial antioxidant function

Novel Adiposity and Biochemical–Anthropometric Indices to Identify Cardiometabolic Risk and Metabolic Syndrome in Mexican Adults

Although several indices used in clinical practice identify cardiometabolic risk (CR) and metabolic syndrome (MetS), it is imperative to develop indices for specific populations. Therefore, we proposed and validated sex-specific indices to identify CR associated with visceral adipose tissue (VAT) accumulation or MetS in Mexican adults. Additionally, a cut-off value for the visceral fat area (VFA) to identify CR was proposed. Clinical, anthropometric, biochemical, and body composition variables were evaluated in 904 subjects (25–45 years old) (84.4% men). Multiple and logistic regressions were used to model the indices and ROC curve analysis to determine predictive performance. An additional cohort (n = 186) was used for indices validation, and Cohen’s kappa coefficient was employed for agreement analysis. The proposed sex-specific indices, called Mexican adiposity indices (MAIs) and biochemical–anthropometric indices (BAIs), were good predictors for CR and MetS. The kappa coefficients showed a moderate agreement level. The VFA cut-off value chosen to identify CR was 100.3 cm2 because it had the best combination of sensitivity (66.8%) and specificity (64.4%). MAIs and BAIs could be clinical tools to identify either CR associated to VAT accumulation or MetS, respectively. A VFA cut-off value of 100.3 cm2 could identify CR in Mexican men

Differential proteomic analysis of the pancreas of diabetic db/db mice reveals the proteins involved in the development of complications of diabetes mellitus

Type 2 diabetes mellitus is characterized by hyperglycemia and insulin-resistance. Diabetes results from pancreatic inability to secrete the insulin needed to overcome this resistance. We analyzed the protein profile from the pancreas of ten-week old diabetic db/db and wild type mice through proteomics. Pancreatic proteins were separated in two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and significant changes in db/db mice respect to wild type mice were observed in 27 proteins. Twenty five proteins were identified by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) and their interactions were analyzed using search tool for the retrieval of interacting genes/proteins (STRING) and database for annotation, visualization and integrated discovery (DAVID). Some of these proteins were Pancreatic α-amylase, Cytochrome b5, Lithostathine-1, Lithostathine-2, Chymotrypsinogen B, Peroxiredoxin-4, Aspartyl aminopeptidase, Endoplasmin, and others, which are involved in the metabolism of carbohydrates and proteins, as well as in oxidative stress, and inflammation. Remarkably, these are mostly endoplasmic reticulum proteins related to peptidase activity, i.e., they are involved in proteolysis, glucose catabolism and in the tumor necrosis factor-mediated signaling pathway. These results suggest mechanisms for insulin resistance, and the chronic inflammatory state observed in diabetes

Efecto del ejercicio máximo y submáximo sobre excreción de albúmina en adultos mayores

Introduction: Microalbuminuria could be induced by strenuous exercise in young and adults. The effects of maximum and submaximal exercise on microalbuminuria in elderly (e»65 years) are not well known. Purpose: To evaluate the effect of different intensities of acute exercise on microalbuminuria. Methods: 20 healthy subjects, 13 men and 7 women (69 ± 4 years). They performed 3 exercise tests a week apart: MAXCAP-B, SUBMAX-B 80% and 60%. Urine samples were collected before, immediately after, one hour and 24 hours after exercise to determine microalbuminuria (20-200 mg/l). Results: microalbuminuria was observed immediately after in MAXCAP-B-B (19,0 mg/l, ± 10,7) and 1 hour post-exercise (18,6 ± 9,4 mg/l) (p 0.05). Conclusion: The High intensity of exercise favor the appearance of microalbuminuria in apparently healthy older adults, this response is moderate and transient. There was no persistent microalbuminuria at 24 hours following the practice of maximum and submaximal exercise. The maximum and submaximal exercise in apparently healthy older adults. This study supports that in performing submaximal exercise maximum (80% and 60%) on renal function in healthy elderly has no adverse impact. Studies should be conducted to measure renal responses to acute exercise in patients with chronic degenerative diseases.Introducción: En jóvenes y adultos la microalbuminuria podría ser inducida por ejercicio físico extenuante. Los efectos del ejercicio máximo y submáximo sobre microalbuminuria en adultos mayores (e»65 años) no son bien conocidos. Objetivo: Evaluar el efecto de diferentes intensidades de ejercicio agudo sobre la microalbuminuria. Métodos: 20 sujetos sanos, 13 hombres y 7 mujeres (69 ± 4 años). Realizaron 3 pruebas de ejercicio físico con una semana de diferencia: MAXCAP-B, SUBMAX-B 80% y SUBMAX-B 60%. Se recolectaron muestras de orina antes, inmediatamente después, una hora y 24 horas después del ejercicio para determinar la microalbuminuria (20 - 200 mg/l). Resultados: Solo se observó una microalbuminuria significativamente más elevada inmediatamente después en MAXCAP-B (19,0 mg/l, ± 10,7) y 1 hora postejercicio (18,6 ± 9,4 mg/l) (p <0,05). A las 24 horas después de las pruebas de ejercicio físico no existió microalbuminuria (p > 0,05). Conclusión La intensidad elevada del ejercicio favorece la aparición de microalbuminuria en los adultos mayores aparentemente sanos, esta respuesta es moderada y transitoria, y debe considerarse en los programas de ejercicio. No existió microalbuminuria persistente a las 24 horas posterior a la práctica de ejercicio físico máximo y submáximo, lo cual indica que en adultos mayores aparentemente sanos el efecto solo es agudo y transitorio. Este estudio soporta que el ejercicio submáximo y máximo (80% y 60%) no tiene impacto desfavorable sobre la función renal en adultos mayores aparentemente sanos. Se deben realizar estudios para medir las respuestas renales al ejercicio agudo en pacientes con enfermedades crónicas degenerativas