Thioredoxin (TRX) is a protein disulfide reductase that plays an important role in many thiol-dependent cellular reductive processes, antioxidant protection, and signal transduction. Moreover, TRX reduces and maintains the function of many proteins during oxidative stress, which is increased in diabetes. The authors recently reported that diabetes impairs brain redox status and TRX response to exercise training. As a continuation of their studies, they hypothesized that alpha-lipoic acid, a natural thiol antioxidant, has a favorable effect on the brain TRX and glutathione (GSH) system in diabetes. Streptozotocin-induced diabetes was used as a chronic model and exhaustive exercise as an acute model for disrupted redox balance. Half the diabetic and nondiabetic animals were subjected to a bout of exhaustive exercise after 8 wk with or without lipoic acid and analyzed for key thiol antioxidants. Lipoic acid neither altered diabetes-induced oxidative stress as assessed by the increased ratio of oxidized to total GSH nor had any impact on the antioxidant protein response to exercise. However, lipoic acid increased mRNA of TRX-interacting protein, an inhibitor of TRX-1, and glutaredoxin-1 in diabetes. Exercise increased TRX-1 mRNA in both diabetic and nondiabetic animals but had no effect on TRX-1 protein. Cytosolic superoxide dismutase mRNA was only increased in diabetes, whereas exercise increased the protein levels in nondiabetic animals. The findings suggest that exhaustive exercise induces mRNA of TRX-1 in the brain and that lipoic acid cannot prevent diabetes-induced disturbances in GSH homeostasis. Because lipoic acid increased TRX-interacting protein transcription in diabetes, high doses may impair TRX-1 homeostasis.
Zekine Lappalainen, Jani Lappalainen, David E. Laaksonen, Niku K.J Oksala, Savita Khanna, Chandan K. Sen and Mustafa Atalay
Alessandra Paiva de Castro, José Rubens Rebelatto and Thaís Rabiatti Aurichio
Wearing inappropriate shoes can cause biomechanical imbalance, foot problems, and pain and induce falls.
To verify the prevalence of wearing incorrectly sized shoes and the relationship between incorrectly sized shoes and foot dimensions, pain, and diabetes among older adults.
A cross-sectional study.
399 older adults (227 women and 172 men) age 60 to 90 y.
Main Outcome Measures:
The participants were asked about the presence of diabetes, pain in the lower limbs and back, and pain when wearing shoes. Foot evaluations comprised the variables of width, perimeter, height, length, first metatarsophalangeal angle, the Arch Index, and the Foot Posture Index. The data analysis was performed using a 2-sample t test and chi-square test.
The percentage of the participants wearing shoe sizes bigger than their foot length was 48.5% for the women and 69.2% for the men. Only 1 man was wearing a shoe size smaller than his foot length. The older adults wearing the incorrect shoe size presented larger values for foot width, perimeter, and height than those wearing the correct size, but there were no significant differences between the groups with respect to the Arch Index and the Foot Posture Index. Incorrectly sized shoes were associated with ankle pain in women but not with diabetes. Men were more likely to wear incorrectly fitting shoes. The use of correctly sized shoes was associated with back pain in women.
The use of incorrectly sized shoes was highly prevalent in the population studied and was associated with larger values for foot width, perimeter, and height and with ankle pain.
Paul D. Loprinzi
Understanding of the objectively measured physical activity (PA) and sedentary patterns of adults with diabetes at the population level is currently limited. Therefore, the purpose of this study was to report accelerometer-determined PA and sedentary patterns among a national sample of U.S. adults with and without evidence of diabetes and to also explore differences across other comorbidity characteristics. Data from the 2003–2006 National Health and Nutrition Examination Survey were used. Four hundred seven participants had evidence of diabetes (mean age = 73.4 years), and 1,346 did not have diabetes (mean age = 74.3 years). Results showed that few older adults meet PA guidelines; the majority of their time is spent in sedentary activities; very few engage in more light-intensity PA than sedentary behavior; and older adults with multiple comorbidities engage in less PA and more sedentary behavior than their counterparts. The development and implementation of feasible, effective PA programs for older adults with multiple comorbidities are warranted.
Sae Young Jae, Kevin Heffernan, Bo Fernhall and Yoon-Ho Choi
We tested the hypothesis that higher levels of cardiorespiratory fitness are inversely associated with carotid artery intima media thickness in 746 (age 53 ± 7 yrs) men with type 2 diabetes.
We measured common carotid intima media thickness and defined carotid atherosclerosis as a carotid intima media thickness > 1.0 mm. Cardiorespiratory fitness was directly measured by peak oxygen uptake using expired gases analysis during a standard treadmill test.
Cardiorespiratory fitness was independently associated with common carotid intima media thickness in multivariable regression (β = –0.15, P < .05). After adjusting for established risk factors, high and moderate cardiorespiratory fitness were associated with lower odds ratios for having carotid atherosclerosis—0.49 (95% CI, 0.30–0.81), and 0.59 (95% CI, 0.38–0.92), respectively—as compared with low cardiorespiratory fitness. Each 1 metabolic equivalent increment higher cardiorespiratory fitness was associated with 27% (OR = 0.73; 95% CI, 0.61–0.87) lower prevalence of carotid atherosclerosis.
These results suggest that high cardiorespiratory fitness is inversely associated with common carotid intima media thickness in men with type 2 diabetes.
Robert Kertzer, Ron Croce, Richard Hinkle and Collette Janson-Sand
Few studies have investigated the fitness levels of children and adolescents with insulin-dependent diabetes mellitus (IDDM), with no data presently available on such children’s level of motor proficiency. The present investigation was prompted by this lack of information. Twenty-one girls (mean age = 11.0 years, range = 7-14) and 23 boys (mean age =11.5 years, range = 8-15) with IDDM were tested on selected fitness and motor behavior parameters. Results indicated that children and adolescents with IDDM follow similar fitness and motor behavior profiles of their nondiabetic peers: Boys tended to be in better physical condition than girls of similar ages, particularly in the 12-15 year range. In the areas of body composition and abdominal strength/endurance, subjects displayed values below those obtained in studies of nondiabetic subjects. Subjects’ scores on the Bruininks-Oseretsky Test of Motor Proficiency for each age grouping were relatively high, indicating that children and adolescents with IDDM need not have diminished psychomotor skills.
William R. Sukala, Rachel Page, Chris Lonsdale, Isabelle Lys, David Rowlands, Jeremy Krebs, Murray Leikis and Birinder Singh Cheema
To evaluate the differential effect of 2, group-based exercise modalities on quality of life (QoL) in indigenous Polynesian peoples with type 2 diabetes (T2DM) and visceral obesity.
Participants were randomized to resistance training or aerobic training performed 3 times per for 16 weeks. The Short-Form 36 was administered at baseline and post intervention to assess 8 domains and physical and mental component scales (PCS and MCS) of QoL.
With the exception of Mental Health and MCS, all scores were lower at baseline than general population norms. Significant improvements were documented in several QoL scores in each group post intervention. No group × time interactions were noted. Pooled analyses of the total cohort indicated significantly improved Physical Functioning, Role-Physical, Bodily Pain, General Health, Vitality, Role-Emotional, PCS and MCS. Adaptation ranged from 5%−22%, and demonstrated a moderate-to-large effect (Cohen’s d = 0.64−1.29). All measures of QoL increased to near equivalent, or greater than general norms.
Exercise, regardless of specific modality, can improve many aspects of QoL in this population. Robust trials are required to investigate factors mediating improvements in QoL, and create greater advocacy for exercise as a QoL intervention in this and other indigenous populations with T2DM.
Cristiane Petra Miculis, Wagner De Campos and Margaret Cristina da Silva Boguszewski
The aim of this study was to correlate glycemic control (GC) and variables of physical activity levels (PAL) in children with type 1 diabetes mellitus (T1DM).
Fifty children and adolescents with T1DM were selected. Personal and medical data for the patients were collected. Physical evaluations of body weight and sexual maturation were undertaken. Bouchard’s questionnaire was applied to evaluate PAL as well as for time spent on physical activities.
Sixty-four percent of the subjects were sexually mature. Differences were observed between females and males in insulin dose, duration of light physical activity, and sleeping time (P < .05). Ninety percent presented poor GC and 80% had a low PAL. Fasting blood glucose (FBG) was significantly correlated with PAL, with sedentary time, and with sleeping time. Glycated hemoglobin (HbA1c) was significantly correlated with sedentary time and sleeping time. Among the three groups of PAL (insufficient × moderate × active) there were differences in HbA1c (%), FBG (mg/dL), duration of disease (years), and insulin dose (UI/kg/day) (P < 0.001).
GC was significantly correlated with PAL. Among the three groups of physical activity level, the most active group was seen to have the best GC.
Joan Kelly, Katrina Edney, Chris Moran, Velandai Srikanth and Michele Callisaya
Physical activity (PA) is important in managing Type 2 Diabetes Mellitus (T2DM). This study aimed to determine 1) the number of daily steps taken by older people with T2DM, 2) if T2DM is associated with taking fewer steps per day and less likelihood of meeting PA guidelines, and 3) whether these associations are modified by age or gender.
PA was obtained by pedometer from 2 cohorts of older adults with and without T2DM. Multivariable regression was used to determine associations between T2DM, mean steps per day and meeting a guideline equivalent (7 100 steps per day).
There were 293 participants with T2DM (mean age 67.6 ± 6.8 years) and 336 without T2DM (mean age 72.1 ± 7.1 years). In women, T2DM was associated with fewer mean steps per day (β = –1306.4; 95% CI –2052.5, –560.3; P = .001) and not meeting the PA guidelines (OR 0.51; 95% CI 0.28, 0.92; P = .03). Associations were not significant in men (P > .05). Only 29.7% of those with T2DM and 33.3% of those without T2DM met PA guidelines.
Greater focus is needed on how to maintain and increase PA in older age with particular focus on women with T2DM.
Valderi Abreu de Lima, Luis Paulo Gomes Mascarenhas, Juliana Pereira Decimo, William Cordeiro de Souza, Anna Louise Stellfeld Monteiro, Ian Lahart, Suzana Nesi França and Neiva Leite
The aim of this study was to evaluate the level of physical activity and cardiorespiratory fitness in teenagers with type 1 diabetes mellitus (T1D) in comparison with healthy scholar participants. Total of 154 teenagers (T1D = 45 and CON = 109). Height, weight, cardiorespiratory fitness (VO2max), and the level of physical activity by the Bouchard’s Physical Activity Record were measured, and glycated hemoglobin (HbA1c) in T1D. The VO2max was lower in the T1D (38.38 ± 7.54) in comparison with the CON (42.44 ± 4.65; p < .05). The VO2max had correlation with the amount of time of moderate-to-vigorous physical activity (r = .63; p = .0001) and an inverse correlation with sedentary activities (r= -0.46; p = .006). In the T1D the levels of HbA1c had an inverse correlation with the amount of time of moderate-to-vigorous physical activity (r= -0.34; p = .041) and correlation with the BMI z-score (r = .43; p = .017). Only 37,8% of the participants in the T1D reached the adequate amount of daily moderate-to-vigorous intensity physical activity, in the CON 81,7% reached the WHO’s recommendation. Conclusion: T1D had less cardiorespiratory capacity then healthy controls, the teenagers of T1D with lower BMI z-score and that dedicated a greater time in moderate-to-vigorous intensity physical activity demonstrated a better glycemic control.
Jane E. Yardley, Jacqueline Hay, Freya MacMillan, Kristy Wittmeier, Brandy Wicklow, Andrea MacIntosh and Jonathan McGavock
Type 2 diabetes is associated with hypertension and an increased risk of cardiovascular disease. In adults, blood pressure (BP) responses to exercise are predictive of these complications. To determine if the hemodynamic response to exercise is exaggerated in youth with dysglycemia (DG) compared with normoglycemic overweight/obese (OB) and healthy weight (HW) controls a cross-sectional comparison of BP and heart rate (HR) responses to graded exercise to exhaustion in participants was performed. DG and OB youth were matched for age, BMI z-score, height and sex. Systolic (SBP) and diastolic BP (DBP) were measured every 2 min, and HR was measured every 1 min. SBP was higher in OB and DG compared with HW youth at rest (p > .001). Despite working at lower relative workloads compared with HW, the BP response was elevated during exercise in OB and DG. For similar HR and oxygen consumption rates, BP responses to exercise were slightly higher in OB and DG compared with HW. OB and DG youth both display elevated resting and exercise BP relative to HW peers. Obesity may play a greater role than dysglycemia in the exaggerated BP response to exercise in youth.