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K B Adamo

Publications and source records attributed to K B Adamo.

7 recordsLinked to original sources
PubMed2005

Influence of Pro12Ala peroxisome proliferator-activated receptor gamma2 polymorphism on glucose response to exercise training in type 2 diabetes.

AIMS/HYPOTHESIS: Exercise training improves glycaemic control in some but not all individuals and little research has been done regarding genetic impact on the exercise training response in type 2 diabetes. The purpose of this study was to investigate the influence of the Pro(12)Ala variant of the peroxisome proliferator-activated receptor (PPAR) gamma2 gene on changes in fasting plasma glucose in response to exercise training. METHODS: The study population comprised 139 sedentary type 2 diabetic patients (age: 54.4+/-7.2; HbA(1)c: 7.7+/-0.9%) who completed 3 months of supervised exercise training. The primary outcome variable in our analysis was the post-intervention change in blood glucose. Other assessments included measures of body composition, insulin sensitivity indices and maximal oxygen uptake (VO(2max)). RESULTS: The frequency of the Ala allele was 8.3% and the genotypes were in Hardy-Weinberg equilibrium. At baseline, neither body composition variables (weight, BMI, waist circumference), glucose homeostasis variables (glucose, insulin, HbA(1)c, homeostasis model assessment method) nor VO(2max) were different between genotypes (wild-type: Pro(12)Pro n=117, Ala carriers: X(12)Ala n=22). The exercise-training intervention led to similar improvements in body composition and glucose homeostasis variables in both genotype groups (p<0.05). The change in fasting plasma glucose was significantly different between PPARgamma2 genotypes (-1.66 mmol/l vs -0.54 mmol/l, Ala carriers and wild-type, respectively) (p=0.034 unadjusted and p=0.089 including baseline glucose) and the significant association between genotype and glucose response remained after adjusting for statistically significant predictors (age, changes in insulin and BMI [p=0.015]) and including baseline glucose, insulin and BMI (p=0.031). CONCLUSIONS/INTERPRETATION: These data suggest that the Pro(12)Ala polymorphism may influence the glycaemic response to exercise in type 2 diabetes.

Adult↗
PubMed2001

Pro- and macroglycogenolysis: relationship with exercise intensity and duration.

We examined the net catabolism of two pools of glycogen, proglycogen (PG) and macroglycogen (MG), in human skeletal muscle during exercise. Male subjects (n = 21) were assigned to one of three groups. Group 1 exercised 45 min at 70% maximal O(2) uptake (VO(2 max)) and had muscle biopsies at rest, 15 min, and 45 min. Group 2 exercised at 85% VO(2 max) to exhaustion (45.4 +/- 3.4 min) and had biopsies at rest, 10 min, and exhaustion. Group 3 performed three 3-min bouts of exercise at 100% VO(2 max) separated by 6 min of rest. Biopsies were taken at rest and after each bout. Group 1 had small MG and PG net glycogenolysis rates (ranging from 3.8 +/- 1.0 to 2.4 +/- 0.6 mmol glucosyl units. kg(-1). min(-1)) that did not change over time. In group 2, the MG glycogenolysis rate remained low and unchanged over time, whereas the PG rate was initially elevated (11.3 +/- 2.3 mmol glucosyl units. kg(-1). min(-1)) and declined (P < or = 0.05) with time. During the first 10 min, PG concentration ([PG]) declined (P < or = 0.05), whereas MG concentration ([MG]) did not. Similarly, in group 3, in both the first and the second bouts of exercise [PG] declined (P < or = 0.05) and [MG] did not, although by the end of the second exercise period the [MG] was lower (P < or = 0.05) than the rest level. The net catabolic rates for PG in the first two exercises were 22.6 +/- 6.8 and 21.8 +/- 8.2 mmol glucosyl units. kg(-1). min(-1), whereas the corresponding values for MG were 17.6 +/- 6.0 and 10.8 +/- 5.6. The MG pool appeared to be more resistant to mobilization, and, when activated, its catabolism was inhibited more rapidly than that of PG. This suggests that the metabolic regulation of the two pools must be different.

Adult↗
PubMed1999

Dietary carbohydrate and its effects on metabolism and substrate stores in sedentary and active individuals.

This review of carbohydrate (CHO) ingestion and exercise addresses three major issues: (a) how CHO ingestion influences CHO and fat stores, (b) how exercise, by changing CHO stores, alters the responses to CHO or fat ingestion, and (c) the roles of CHO in exercise performance and metabolism. Dietary manipulation is not a simple issue; increasing the dietary content of any specific nutrient alters the entire diet composition. High CHO diets are often low fat diets, hence changing the metabolism and storage of both fat and CHO. Acute CHO ingestion increases CHO oxidation and the "spared" fats are deposited as fat. Chronic high CHO ingestion (without an active lifestyle) leads to muscle becoming insulin-insensitive, adipose tissue processing CHO to fatty acids, and the liver increasing production of VLDL triglycerides. CHO ingestion prior to and during prolonged exercise can increase endurance. It has been suggested that moderate or low glycemic index forms be used prior to and during the exercise, but there is no consensus as to whether it should be a recommendation. The physiological nature of the regulation of CHO stores is poorly understood, but the recent identification of a key enzyme, glycogenin, and two forms of glycogen (pro- and macroglycogen) show promise of a deeper understanding.

Body Composition↗
PubMed1998

Dietary carbohydrate and postexercise synthesis of proglycogen and macroglycogen in human skeletal muscle.

This study examined the role of carbohydrate (CHO) ingestion on the resynthesis of two pools of glycogen, proglycogen (PG) and macroglycogen (MG), in human skeletal muscle. Nine males completed an exhaustive glycogen depletion exercise bout at 70% maximal O2 consumption on two occasions. Subsequent 48-h dietary interventions consisted of either high (HC, 75% of energy intake) or low (LC, 32% of energy intake) CHO diets. Muscle biopsies were taken at exhaustion (EXH) and 4, 24, and 48 h later. The total muscle glycogen (Gt) at EXH for the HC and LC conditions was not significantly different, and the MG represented approximately 12% of the Gt. From EXH to 4 h, there was an increase in the PG only for HC and no change in MG in either diet (P < 0.05). From 4 to 24 h, the concentration of PG increased in both conditions (P < 0.05). Between 24 and 48 h, in HC the majority of the increase in Gt was due to the MG pool (P < 0.05). The MG and PG concentrations for HC were significantly greater than for LC at 24 and 48 h (P < 0.05). At 48 h the MG represented 40% of the Gt for the HC diet and only 21% for the LC diet. There was no change in the net rates of synthesis of PG or MG over 48 h for LC (P < 0.05). The net rate of PG synthesis from 0 to 4 h for HC was 16 +/- 1.68 mmol glucosyl units . kg dry wt-1 . h-1, which was threefold greater than for LC (P < 0. 05). The net rate of PG synthesis decreased significantly from 4 to 24 h for HC, whereas the net rate of MG synthesis was not different over 48 h but was significantly greater than in LC (P < 0.05). The two pools are synthesized at very different rates; both are sensitive to CHO, and the supercompensation associated with HC is due to a greater synthesis in the MG pool.

Adult↗
PubMed1998

Comparison of traditional measurements with macroglycogen and proglycogen analysis of muscle glycogen.

Traditionally, there have been two methods for measuring total muscle glycogen (Glytot), either by acid hydrolysis (AC) or by enzymatic hydrolysis (EZ). As well, it has been determined that rodent muscle contains two pools of glycogen, macroglycogen (MG) and proglycogen (PG). This MG/PG determination of Glytot has never been compared with AC or EZ methods, nor has it been determined whether the two pools exist in human skeletal muscle. A detailed comparison of the three methods was performed by using both rodent and human muscle. It was found that repeated analysis of independent portions of muscle generally gave coefficients of variation of <10%. The PG fraction was always in excess of MG, which was 6-10% of Glytot in rodent muscle and in human samples when Glytot was low but increased to approximately 40% when Glytot was high. It was found that AC and EZ Glytot were not statistically different (P < 0.05), nor was there a difference between the MG+PG Glytot and that determined by AC or EZ. The Glytot from MG+PG extraction had a strong correlation with the values obtained by either AC (r = 1.0) or EZ (r = 0.96). These data suggest that MG+PG do exist in human skeletal muscle and can be measured reliably in biopsy-sized samples. All three methods give an accurate representation of human Glytot and are comparable in their precision.

Animals↗
PubMedDate not supplied

The Finnish sauna bath and its use in patients with cardiovascular disease.

The Finnish tradition of sauna bathing is meant to be an experience in relaxation, and the length of time spent in the sauna and the preferred temperature vary considerably among individuals. The pleasures of sauna bathing can be considered safe and without undue risk of cardiac complications even for CVD patients, providing bathing is conducted sensibly for an appropriate period of time, and extremes in temperature are voided.

Adult↗