Exercise strategies to optimize glycemic control in type 2 diabetes: a continuing glucose monitoring perspective

The effects of extracellular vesicles and their cargo on metabolism and its adaptation to physical exercise in insulin resistance and type 2 diabetes

Lifestyle modification represents the first-line strategy for the prevention and treatment of type 2 diabetes mellitus (T2DM), which is frequently associated with obesity and characterized by defective pancreatic insulin secretion and/or insulin resistance. Exercise training is an essential component of lifestyle modification and has been shown to ameliorate insulin resistance by reducing body fat mass and by enhancing skeletal muscle mitochondrial biogenesis and insulin-independent glucose uptake. Additionally, exercising stimulates the release of exerkines such as metabolites or cytokines, but also long non-coding RNA, microRNAs, cell-free DNA (cf-DNA), and extracellular vesicles (EVs), which contribute to inter-tissue communication. There is emerging evidence that EV number and content are altered in obesity and T2DM and may be involved in several metabolic processes, specifically either worsening or improving insulin resistance. This review summarizes the current knowledge on the metabolic effects of exercise training and on the potential role of humoral factors and EV as new biomarkers for early diagnosis and tailored treatment of T2DM.

The Role of Natural Antioxidant Products That Optimize Redox Status in the Prevention and Management of Type 2 Diabetes

The worldwide prevalence of type 2 diabetes (T2D) and prediabetes is rapidly increasing, particularly in children, adolescents, and young adults. Oxidative stress (OxS) has emerged as a likely initiating factor in T2D. Natural antioxidant products may act to slow or prevent T2D by multiple mechanisms, i.e., (1) reducing mitochondrial oxidative stress, (2) preventing the damaging effects of lipid peroxidation, and (3) acting as essential cofactors for antioxidant enzymes. Natural antioxidant products should also be evaluated in the context of the complex physiological processes that modulate T2D-OxS such as glycemic control, postprandial OxS, the polyol pathway, high-calorie, high-fat diets, exercise, and sleep. Minimizing processes that induce chronic damaging OxS and maximizing the intake of natural antioxidant products may provide a means of preventing or slowing T2D progression. This "optimal redox" (OptRedox) approach also provides a framework in which to discuss the potential benefits of natural antioxidant products such as vitamin E, vitamin C, beta-carotene, selenium, and manganese. Although there is a consensus that early effective intervention is critical for preventing or reversing T2D progression, most research has focused on adults. It is critical, therefore, that future research include pediatric populations.

Physical activity can improve diabetes patients' glucose control; A systematic review and meta-analysis

Background

Glycemic control is vital to patient care, and it is still the most important treatment goal for reducing organ damage and other complications associated with diabetes. Physical activity is one of the factors that affects glycemic management. Therefore, the aim of this systematic review and meta-analysis was to find, evaluate, and synthesize the best available information on the link between physical exercise and glycemic control in Ethiopian diabetes patients.

Methods

Pubmed, Science Direct, Google Scholar and African Journals Online were the databases searched. In addition, gray literature were explored. All papers chosen for inclusion in the review underwent a thorough critical appraisal utilizing the Joanna Briggs Institute's standardized critical appraisal instruments (JBI critical appraisal checklist-2017). For statistical analysis and descriptive synthesis, quantitative articles were combined. The Odds ratio and their 95% confidence intervals were generated. Papers that were of excellent quality but lacked the main outcome (physical activity) for meta-analysis were subjected to descriptive synthesis.

Results

The finding of this meta-analysis showed diabetes patients who were physically active had controlled their blood glucose levels by 2.4 times compared to their counter (Odds ratio = 2.40, 95% Confidence Interval = 1.57,3.69). The duration of disease was found to be the most commonly reported predictor for poor glycemic control followed by dietary habits, patients' sex and age.

Conclusion

Physical activity, which is a simple and inexpensive therapy for diabetes patients, can help them control their blood glucose levels. Patients with diabetes who have had it for a long time should be aware of the need of regular physical activity in maintaining blood glucose control.

An evaluation of lower urinary tract symptoms in diabetic patients: a cross-sectional study

BACKGROUND

Lower urinary tract symptoms (LUTS) are common among diabetic patients and represent hidden and mysterious morbidity. The pathophysiology of LUTS among diabetes mellitus (DM) patients is multifactorial. Importantly, LUTS is known to cause physical and psychological distress. Thus, this study describes LUTS among DM patients, investigates factors that may associate with it, and assesses the possible relationship between LUTS and the quality of life of diabetics.

METHODS

Over 6 months, data were collected from 378 diabetic patients in primary health care clinics. Demographic and clinical characteristics, Urogenital Distress Inventory-6 (UDI-6), and Incontinence Impact Questionnaire-7 (IIQ-7) were used to collect data. Univariate and multivariate analyses were performed.

RESULTS

Three hundred seventy-eight participants were included in this study. (29.9%) were (58-67) years old. 49% were female. Half of the cohort was overweight, and a third were obese. 81% were Type 2 DM. Almost all of them are on medical treatment. A median score of 5.50 (2.00-8.00) for the UDI-6 scale and a median score of 5 (0.00-10.00) for the IIQ-7 scale were reported. Multiple linear regression models showed that residency (p = 0.038) and regular exercise (p = 0.001) were significantly and negatively correlated with the UDI-6 score, while female gender (p = 0.042), insulin use (p = 0.009) and the presence of comorbidities (p = 0.007) were positively correlated with this score. Furthermore, age (p = 0.040) and body mass index (BMI) (p < 0.001) were significantly and positively associated with the IIQ-7 score.

CONCLUSION

LUTS is significant morbidity among DM patients. Factors such as age, BMI, and co-morbidities exacerbate LUTS, which can be modified and controlled. On the other hand, regular exercise and weight loss strategies help diabetic patients to improve LUTS.

Associations between Physical Activity Level and Health Services Use in Spanish Adults

One of the main concerns of governments and organisations worldwide is the cost and burden of health services, with sedentary lifestyles being a significant impacting factor, and physical activity is one of the potential solutions. Therefore, this study aims to analyse the possible associations between the physical activity level, hospitalisation prevalence, and the use and number of visits to emergency services in the Spanish population, examining potential differences between sex and age groups. This is a cross-sectional study based on data from the Spanish National Health Survey 2017 (ENSE 2017), the last one before the COVID-19 pandemic, with 17,199 participants. A descriptive analysis was performed using median and interquartile range (continuous variables) and absolute and relative frequencies (ordinal variables). Intergroup differences were analysed with non-parametric tests: chi-square and z-test for independent proportions (categorical variables), and Kruskal−Wallis and Mann−Whitney U (continuous variables). Spearman’s rho was used to study correlations between variables. A multiple binary regression analysis was performed to predict hospitalisations. Hospitalisations and emergency services use showed a dependence relation with the physical activity level (p < 0.001): those who performed moderate and/or vigorous physical activity used those services less than sedentary individuals and those whose only activity was walking. Thus, associations could be drawn between the hospitalisation prevalence, the use and number of visits to emergency departments, and the physical activity level in the Spanish population aged 18−69 years in the pre-pandemic period.

One Bout of Resistance Training Does Not Enhance Metformin Actions in Prediabetic and Diabetic Individuals

PURPOSE

This study aimed to determine the separated and combined effects of metformin and resistance exercise on glycemic control, insulin sensitivity, and insulin-like growth factor 1 (IGF-1) in overweight/obese individuals with prediabetes and type 2 diabetes mellitus.

METHODS

Fourteen adults with a body mass index of 32.1 ± 4.1 kg·m-2, insulin resistance (HOMA-2 1.6 ± 0.6), and poor glycemic control (glycated hemoglobin, 6.9% ± 0.9%; 51.9 ± 10.7 mmol·mol-1) while taking metformin (1561 ± 470 g·d-1) were recruited. Participants underwent four 72-h long experimental trials in a randomized counterbalanced order, either 1) taking metformin (MET), 2) replacing metformin by placebo pills (PLAC), 3) taking placebo and undergoing a resistance training bout (RT + PLAC), and 4) taking metformin and undergoing the same RT bout (RT + MET). Interstitial fluid glucose concentration was frequently sampled to obtain 72-h glucose area under the curve (GAUC) and the percentage hyperglycemic glucose readings (>180 mg·dL-1; GPEAKS). Insulin sensitivity (i.e., HOMA-2) and IGF-1 were also assessed.

RESULTS

HOMA-2 was not affected by treatments. GAUC and GPEAKS were similarly reduced below PLAC during RT + MET and MET (all P < 0.05). In contrast, RT + PLAC did not affect glucose concentration. Metformin decreased serum IGF-1 concentrations (P = 0.006), and RT did not reverse this reduction.

CONCLUSIONS

A bout of full-body RT does not interfere or aid on metformin's blood glucose-lowering actions in individuals with prediabetes and type 2 diabetes mellitus.

Lessons From COVID-19: Physical Exercise Can Improve and Optimize Health Status

The outbreak of Coronavirus Disease 2019 (COVID-19) has caused increasing challenges for healthcare systems globally. The disease spread rapidly from Wuhan to the rest of the world, involving more than 400 million individuals and including more than 5 million deaths. In dealing with the pandemic, China and other countries took protective measures such as promoting social distancing, canceling public gatherings, closing schools, quarantining, and imposing lockdowns. All these measures lead to physical inactivity. Being physically inactive has significant repercussions on the status of physical and mental wellbeing, and it is associated with anxiety, stress, increased chronic disease risk, and worsening of chronic conditions. In this sense, the relevance of maintaining a healthy lifestyle through physical exercise has been outlined by the World Health Organization (WHO). The aim of this mini review is to discuss the importance of physical activity in the context of the COVID-19 pandemic, highlighting the benefits of physical activity and exercise that could be potentially effective treatment strategies for comorbid chronic conditions, long covid syndrome (LCS), and symptoms such as depression and anxiety.

Diet and Physical Activity as Determinants of Continuously Measured Glucose Levels in Persons at High Risk of Type 2 Diabetes

We examined how dietary and physical activity behaviors influence fluctuations in blood glucose levels over a seven-day period in people at high risk for diabetes. Twenty-eight participants underwent a mixed meal tolerance test to assess glucose homeostasis at baseline. Subsequently, they wore an accelerometer to assess movement behaviors, recorded their dietary intakes through a mobile phone application, and wore a flash glucose monitoring device that measured glucose levels every 15 min for seven days. Generalized estimating equation models were used to assess the associations of metabolic and lifestyle risk factors with glycemic variability. Higher BMI, amount of body fat, and selected markers of hyperglycemia and insulin resistance from the meal tolerance test were associated with higher mean glucose levels during the seven days. Moderate- to vigorous-intensity physical activity and polyunsaturated fat intake were independently associated with less variation in glucose levels (CV%). Higher protein and polyunsaturated fatty acid intakes were associated with more time-in-range. In contrast, higher carbohydrate intake was associated with less time-in-range. Our findings suggest that dietary composition (a higher intake of polyunsaturated fat and protein and lower intake of carbohydrates) and moderate-to-vigorous physical activity may reduce fluctuations in glucose levels in persons at high risk of diabetes.

Alterations in Glycemic Variability, Vascular Health, and Oxidative Stress following a 12-Week Aerobic Exercise Intervention-A Pilot Study

The state of being overweight or obese leads to an increased risk of development of cardiometabolic disease. Increases in glycemic variability have been associated with greater induction of oxidative stress and declined vascular health, which may be exacerbated by higher weight status and improved through exercise. The purpose of this study was to examine the impact of a twelve-week aerobic exercise intervention on continuous glucose monitor (CGM) assessed glucose concentrations and glycemic variability, and biomarkers of vascular health and oxidative stress in overweight or obese adults. Eight adults (Age = 48.9 ± 5.2 years; BMI = 29.4 ± 8.3 kg/m2) completed a twelve-week aerobic exercise intervention. Participants walked three times per week at moderate intensity for ~150 minutes each week. All participants wore a CGM for seven consecutive days at baseline and post-intervention. On the final day of monitoring, a fasting blood sample was collected, and an oral glucose tolerance test (OGTT) was performed. Intra- and inter-day glycemic variability was assessed as the mean amplitude of glycemic excursions, continuous overlapping net glycemic action of one-, two-, and four-hour, and the mean observation of daily differences. Plasma concentrations of nitric oxide (NO) and myeloperoxidase (MPO) were measured, and their ratio was calculated (NO:MPO). No CGM-assessed glucose concentrations or measures of glycemic variability changed from baseline to post-intervention. MPO concentration decreased (24.8 ± 8.2 ng/mL to 16.4 ± 4.6 ng/mL, p < 0.01), the NO:MPO ratio improved (3.5:1 to 6.4:1, p < 0.01) following the twelve-week intervention. Individual level changes in body weight and V̇O₂peak were found. In conclusion, twelve weeks of aerobic exercise reduced oxidative stress and improved the propensity to vasodilate but did not alter CGM-assessed glucose concentrations or glycemic variability in this group of overweight or obese non-diabetic adults. These findings may be due to individual changes in body weight or V̇O2peak, which necessitates further research to explore their influence on these outcomes of interest.

An Analysis of Individual and Contextual-Level Disparities in Screening, Treatment, and Outcomes for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver and affects patients of all genders, races, ethnicities, and socioeconomic status. While the causes of HCC are numerous, the primary etiology is cirrhosis from alcohol and non-alcoholic fatty liver disease in the United States and from infectious agents such as Hepatitis B and Hepatitis C in the developing world. In patients at-risk for developing HCC, screening is recommended with ultrasound imaging and alpha fetoprotein laboratory tests. In socioeconomically vulnerable patients, however, individual-level barriers (eg, insurance status) and contextual-level disparities (eg, health facilities) may not be readily available, thus limiting screening. Additional challenges faced by racial/ethnic minorities can further challenge the spectrum of HCC care and lead to inadequate screening, delayed diagnosis, and unequal access to treatment. Efforts to improve these multilevel factors that lead to screening and treatment disparities are critical to overcoming challenges. Providing health insurance to those without access, improving societal challenges that confine patients to a lower socioeconomic status, and reducing challenges to seeking healthcare can decrease the morbidity and mortality of these patients. Additionally, engaging with communities and allowing them to collaborate in their own healthcare can also help to attenuate these inequities. Through collaborative multidisciplinary change, we can make progress in tackling disparities in vulnerable populations to achieve health equity

Circadian Rhythm of Blood Pressure of Dipper and Non-dipper Patients With Essential Hypertension: A Mathematical Modeling Approach

Blood pressure in humans presents a circadian variation profile with a morning increase, a small postprandial valley, and a deeper descent during night-time rest. Under certain conditions, the nocturnal decline in blood pressure can be reduced or even reversed (non-dipper), which is related to a significantly worse prognosis than a normal fall pattern (dipper). Despite several advances in recent years, our understanding of blood pressure's temporal structure, its sources and mechanisms is far from complete. In this work, we developed an ordinary differential equation-based mathematical model capable of capturing the circadian rhythm of blood pressure in dipper and non-dipper patients with arterial hypertension. The model was calibrated by means of global optimization, using 24-h data of systolic and diastolic blood pressure, physical activity, heart rate, blood glucose and norepinephrine, obtained from the literature. After fitting the model, the mean of the normalized error for each data point was <0.2%, and confidence intervals indicate that all parameters were identifiable. Sensitivity analysis allowed identifying the most relevant parameters and therefore inferring the most important blood pressure regulatory mechanisms involved in the non-dipper status, namely, increase in sympathetic over parasympathetic nervous tone, lower influence of physical activity on heart rate and greater influence of physical activity and glucose on the systemic vascular resistance. In summary, this model allows explaining the circadian rhythm of blood pressure and deepening the understanding of the underlying mechanisms and interactions integrating the results of previous works.

Self-reported and objectively measured physical activity levels among Hispanic/Latino adults with type 2 diabetes

OBJECTIVE

In the USA, minority populations face a disproportionate burden from type 2 diabetes (T2D), in whom physical activity (PA) is recommended. The aim of this study was to determine levels of PA among a community of free-living Hispanic/Latino adults with T2D using a research accelerometer, a consumer device and a pictogram self-assessment questionnaire.

RESEARCH DESIGN AND METHODS

This was a cross-sectional, observational study. Participants (57 women and 31 men, body mass index (kg/m²) 32.2±7.9 and 29.9±4.5, waist circumference 97.1±30.1 and 93.7±33.0 cm and hemoglobin A1c 8.0±2.0 and 8.1%±1.8%, respectively) wore an ActiGraph (AG) on the hip and a Fitbit (FB) on the wrist for 1 week to estimate daily steps and energy expenditure (EE). Participants reported type and intensity of PA using English-language or Spanish-language pictograms and a 10-point Likert scale (1='not active' to 10='very, very active').

RESULTS

Steps per day were not normally distributed; AG median steps/weekday (Monday-Friday) was 6990 (range 1091-25 884) compared with 9329 (288-31 669) using FB (p≤0.01). Both devices recorded significantly more steps on weekdays versus weekends (p≤0.05). EE was also higher during the week. AG and FB were highly correlated to each other (p<0.01). Men were more active than women and maintained their PA throughout the week, whereas women decreased theirs on weekends. Spanish-language pictograms were preferred and self-reported PA matched objective assessments by both devices. Participants perceived themselves to be active (7.1±2.0) due to work.

CONCLUSIONS

Both objectively measured and self-reported levels of PA in Hispanic/Latino adults with T2D challenge the assumption that lack of PA may be commonplace for this group. AG and FB are different in their measurement of PA but are significantly correlated. New strategies, including use of pictograms, for interventions need to be considered if further increases or changes in PA are to be used as T2D therapy.

TRIAL REGISTRATION NUMBER

NCT03736486.

Portable Gentle Jogger Improves Glycemic Indices in Type 2 Diabetic and Healthy Subjects Living at Home: A Pilot Study

BACKGROUND

Physical inactivity is a high-risk factor for type 2 diabetes. Increased physical activity improves indices of glycemic control. Continuous glucose monitoring (CGM) allows the investigation of glycemic control during activities of daily living. A pilot study was undertaken to determine the effects of the portable Gentle Jogger (passive simulated jogging device (JD)) that decreases physical inactivity by effortlessly producing body movements on glycemic indices of healthy and type 2 diabetes subjects using CGM during activities of daily living.

METHODS

A single-arm, nonblinded study was carried out in 22 volunteers (11 type 2 diabetics and 11 healthy subjects), using continuous glucose monitoring (CGM) for 14 days. On day 4, subjects were provided with JD and instructed to use it a minimum of 3 times per day for 30 min for 7 days. CGM data was analyzed at baseline (BL) and during 2, 3, 4, 5, 6, and 7 days of JD (JD 2, 3, 4, 5, 6, 7) and 1-2-day post JD (Post JD1 and 2) and the following 24 hr indices computed mean glucose (mGLu), SUM of all glucose values, % coefficient of variation (%CV), area under the 24-hour curve (AUC), time spent above range (TAR, glucose 180-250 mg/dl), and time in range (TIR).

RESULTS

In healthy subjects, there were significantly lower values of mGlu and SUM compared to BL for all days of JD usage. In type 2 diabetics, mGlu, SUM, and AUC were significantly lower compared to BL, for all days of JD usage and Post JD1. TAR was significantly lower and TIR significantly improved during JD, in type 2 diabetics without change in %CV.

CONCLUSION

Gentle Jogger is a portable, passive movement technology that reduces physical inactivity while improving 24 hr glycemic control. It can be self-administered as a standalone device or as an adjunct to diabetic medications. This trial is registered with NCT03550105.

Role of the physical fitness test in risk prediction of diabetes among municipal in-service personnel in Guangxi

To explore the relationship between risk prediction of diabetes mellitus (DM) and different physical fitness parameters in municipal in-service personnel in Guangxi.This was a cross-sectional study conducted in China from July 2015 to December 2016. We enrolled in-service adults (20-65 year of age) from public institutions. All subjects underwent National Physical Fitness Test (NPFT) and EZSCAN screening.The 5668 subjects were 42.9±12.3 years; 2984 (52.6%) were male; 3998 (70.5%), 1579 (27.9%) and 85 (1.6%) were Han, Zhuang, and other ethnicities, respectively. The multivariable analysis showed that systolic blood pressure (odds ratio [OR] = 1.013, 95% confidence interval [CI]: 1.003-1.022, P = .01), Harvard step test index (OR = 0.958, 95% CI: 0.941-0.976, P <.001), bend-ahead in sitting (OR = 0.945, 95% CI: 0.926-0.963, P <.001), hand grip strength (OR = 0.981, 95% CI: 0.966-0.997, P = .02), vertical jump height (OR = 0.969, 95% CI: 0.944-0.996, P = .02), time of single-leg standing with eyes closed (OR = 0.981, 95% CI: 0.968-0.995, P = .007), choice reaction time (OR = 2.103, 95% CI: 1.261-3.507, P = .004), and body composition minerals (OR = 1.649, 95% CI: 1.261-1.813, P < .001) were independently associated with DM. The resulting equation for the prediction of DM had an area under the receiver operating characteristic curve of 0.808, indicating good predictive ability.NPFT and EZSCAN could help predict the risk of diabetes and give early warnings to undertake preventive actions such as changing diet and performing physical activity.

Effect of patient characteristics on medication adherence among patients with type 2 diabetes mellitus: a cross-sectional survey

Background: The prevalence of diabetes mellitus (DM) is steadily increasing worldwide, with a significant DM population in Asian countries. Adherence to medications is important to achieve good glycaemic control among patients with DM. Thus, patients' adherence to their medication regimen should be determined to optimise DM management. Aims: To determine medication adherence and the relationship between patient profile and medication adherence among patients with type 2 DM (T2DM). Design: Cross-sectional survey. Methods: This study was conducted in a public hospital in Selangor, Malaysia, from December 2016 to June 2017. Data was obtained through administration of the Medication Compliance Questionnaire and an electronic medical records database. Multivariate logistic regression analysis was used to determine the predictors of medication adherence. Results: A total of 232 (95.9% response rate) patients participated in this study. The overall percentage of medication adherence among patients with DM was 55.2%. The majority of participants were female (53.4%), Malay (47.0%), aged 41-64 years (55.2%; mean age, 56.69 years), married (84.5%), unemployed (60.8%) and attended secondary school (53.9%). The factors independently associated with adherence were ethnicity (odds ratio [OR], 1.43; 95% confidence interval [CI]: 1.03-1.99) and haemoglobin A1c (HbA1c) level (OR, 2.71; 95% CI: 1.56-4.72). Conclusions: The medication adherence among patients with DM in a public hospital in Selangor, Malaysia was low. A health intervention emphasising patient-centred care is warranted to improve DM patients' adherence to prescribed medication. Considering that Malaysia has a multi-ethnic population, the patients' ethnicity and their HbA1c levels need to be considered in the implementation of any intervention to improve medication adherence. Impact statement: Medication adherence is influenced by individual patients' characteristics. To improve adherence to the medication regimen, nurses should consider patients' profiles.

Randomized Controlled Trial of Physical Exercise in Diabetic Veterans With Length-Dependent Distal Symmetric Polyneuropathy

Rationale: Physical exercise is an essential adjunct to the management of patients with type 2 diabetes mellitus. Therapeutic interventions that improve blood flow to peripheral nerves, such as exercise, may slow the progression of neuropathy in the diabetic patient.

Aims: This randomized clinical trial was conducted to determine whether a structured program of aerobic, isokinetic strength, or the combination of aerobic–isokinetic strength exercise intervention alters peripheral nerve function in glycemic-controlled diabetic patients with advanced length-dependent distal symmetric polyneuropathy.

Methods: Forty-five patients with type 2 diabetes mellitus exhibiting tight glycemic control (HbA_1c intergroup range 7.2–8.0%) were randomized by block design across four experimental groups: sedentary controls (n = 12), aerobic exercise (n = 11), isokinetic strength (n = 11), or the combination of aerobic–isokinetic strength training (n = 11). Patients randomized to training groups exercised 3× per week for 12 weeks, whereas patients randomized to the sedentary control group received standard of care. To minimize attention and educational bias, all patients attended a 12-session health promotion educational series. At baseline, immediately following intervention, and again at 12-week post-intervention, detailed nerve conduction studies were conducted as a primary outcome measure. At these same intervals, all patients completed as secondary measures quantitative sensory testing, symptom-limited treadmill stress tests, and a Short-Form 36-Veterans Questionnaire (SF-36V).

Results: Of the 45 patients randomized into this study, 37 (82%) had absent sural nerve responses, 19 (42%) had absent median sensory nerve responses, and 17 (38%) had absent ulnar sensory nerve responses. By comparison, responses from tibial nerves were absent in only three (7%) subjects while responses from peroneal nerves were absent in five (11%) subjects. Eleven (92%) of 12 patients that had volunteered to be biopsied exhibited abnormal levels of epidermal nerve fiber densities. Exercise, regardless of type, did not alter sensory or motor nerve electrodiagnostic findings among those patients exhibiting measurable responses (ANOVA). There was, however, a modest (p = 0.01) beneficial effect of exercise on sensory nerve function (Fisher’s Exact Test). Importantly, the beneficial effect of exercise on sensory nerve function was enhanced (p = 0.03) during the post-intervention interval. In addition, three of six patients that had undergone exercise intervention exhibited a marked 1.9 ± 0.3-fold improvement in epidermal nerve fiber density. By comparison, none of three sedentary patients whom agreed to be biopsied a second time showed improvement in epidermal nerve fiber density. Compared to baseline values within groups, and compared with sedentary values across groups, neither aerobic, isokinetic strength, or the combination of aerobic–isokinetic strength exercise intervention altered peak oxygen uptake. Patients that underwent aerobic or the combined aerobic–isokinetic strength exercise intervention, however, demonstrated an increase in treadmill test duration that was sustained over the 12-week post-intervention period.

Conclusion: A 12-week course of physical exercise, regardless of type, does not alter sensory or motor nerve electrodiagnostic findings. In a subset of patients, a short-term structured program of aerobic exercise may selectively improve sensory nerve fiber function. Large-scale exercise lifestyle intervention trials are warranted to further evaluate the impact of aerobic exercise on sensory nerve fiber function in diabetic neuropathic patients.

Clinical Trial Registration:www.ClinicalTrials.gov, identifier NCT00955201.

Physical Exercise Improves Glycemic and Inflammatory Profile and Attenuates Progression of Periodontitis in Diabetic Rats (HFD/STZ)

The authors aimed to evaluate the effects of physical exercise on the metabolism and progression of periodontal disease (PD), induced by ligature in diabetic rats induced by high fat diet and streptozotocin (HFD/STZ). Diabetes Mellitus (DM) was induced by four weeks of a hyperlipidic diet associated with a single low-dose of streptozotocin (35 mg/kg/animal). The exercise groups swam for 60 min/day for eight weeks (five times/week). In the last two weeks of exercise, a ligature was placed around the right and left mandibular first molars. The authors determined alveolar bone loss by morphometry. Blood biochemical profile and serum levels of IL-10 and TNF-α were evaluated by colorimetric and enzyme-linked immunosorbent assays (ELISA), respectively. The diabetic animals subjected to exercise showed decreased alveolar bone loss, lower glycemia, triacylglycerols and glycosylated hemoglobin levels than the controls. Total cholesterol and its fractions (High density lipoprotein—HDL-c, Low density lipoprotein—LDL-c and Very low density lipoprotein—VLDL-c) remained similar among the groups. Animals with PD showed higher levels of TNF-α and lower levels of IL-10, when compared to animals without PD. In diabetic animals with PD, physical exercise decreased TNF-α levels and increased IL-10 levels as well as the IL10/TNF-α ratio. In conclusion, eight weeks of physical exercise improved glycemic control and systemic inflammatory profile, and attenuated alveolar bone loss in rats with DM and PD.

Wearable Contact Lens Biosensors for Continuous Glucose Monitoring Using Smartphones

Low-cost, robust, and reusable continuous glucose monitoring systems that can provide quantitative measurements at point-of-care settings is an unmet medical need. Optical glucose sensors require complex and time-consuming fabrication processes, and their readouts are not practical for quantitative analyses. Here, a wearable contact lens optical sensor was created for the continuous quantification of glucose at physiological conditions, simplifying the fabrication process and facilitating smartphone readouts. A photonic microstructure having a periodicity of 1.6 μm was printed on a glucose-selective hydrogel film functionalized with phenylboronic acid. Upon binding with glucose, the microstructure volume swelled, which modulated the periodicity constant. The resulting change in the Bragg diffraction modulated the space between zero- and first-order spots. A correlation was established between the periodicity constant and glucose concentration within 0-50 mM. The sensitivity of the sensor was 12 nm mM^-1, and the saturation response time was less than 30 min. The sensor was integrated with commercial contact lenses and utilized for continuous glucose monitoring using smartphone camera readouts. The reflected power of the first-order diffraction was measured via a smartphone application and correlated to the glucose concentrations. A short response time of 3 s and a saturation time of 4 min was achieved in the continuous monitoring mode. Glucose-sensitive photonic microstructures may have applications in point-of-care continuous monitoring devices and diagnostics at home settings.

hIAPP forms toxic oligomers in plasma

In diabetes, hyperamylinemia contributes to cardiac dysfunction. The interplay between hIAPP, blood glucose and other plasma components is, however, not understood. We show that glucose and LDL interact with hIAPP, resulting in β-sheet rich oligomers with increased β-cell toxicity and hemolytic activity, providing mechanistic insights for a direct link between diabetes and cardiovascular diseases.

Skeletal Muscle Microvascular-Linked Improvements in Glycemic Control From Resistance Training in Individuals With Type 2 Diabetes

OBJECTIVE

Insulin increases glucose disposal in part by enhancing microvascular blood flow (MBF) and substrate delivery to myocytes. Insulin's microvascular action is impaired with insulin resistance and type 2 diabetes. Resistance training (RT) improves glycemic control and insulin sensitivity, but whether this improvement is linked to augmented skeletal muscle microvascular responses in type 2 diabetes is unknown.

RESEARCH DESIGN AND METHODS

Seventeen (11 male and 6 female; 52 ± 2 years old) sedentary patients with type 2 diabetes underwent 6 weeks of whole-body RT. Before and after RT, participants who fasted overnight had clinical chemistries measured (lipids, glucose, HbA_1c, insulin, and advanced glycation end products) and underwent an oral glucose challenge (OGC) (50 g × 2 h). Forearm muscle MBF was assessed by contrast-enhanced ultrasound, skin MBF by laser Doppler flowmetry, and brachial artery flow by Doppler ultrasound at baseline and 60 min post-OGC. A whole-body DEXA scan before and after RT assessed body composition.

RESULTS

After RT, muscle MBF response to the OGC increased, while skin microvascular responses were unchanged. These microvascular adaptations were accompanied by improved glycemic control (fasting blood glucose, HbA_1c, and glucose area under the curve [AUC] during OGC) and increased lean body mass and reductions in fasting plasma triglyceride, total cholesterol, advanced glycation end products, and total body fat. Changes in muscle MBF response after RT significantly correlated with reductions in fasting blood glucose, HbA_1c, and OGC AUC with adjustment for age, sex, % body fat, and % lean mass.

CONCLUSIONS

RT improves OGC-stimulated muscle MBF and glycemic control concomitantly, suggesting that MBF plays a role in improved glycemic control from RT.

Moderate intensity sports and exercise is associated with glycaemic control in women with gestational diabetes

AIM

To assess the association of regular, unsupervised sports and exercise during pregnancy, by intensity level, with glycaemic control in women with gestational diabetes (GDM).

METHODS

Prospective cohort study of 971 women who, shortly after being diagnosed with GDM, completed a Pregnancy Physical Activity Questionnaire assessing moderate and vigorous intensity sports and exercise in the past 3 months. Self-monitored capillary glucose values were obtained for the 6-week period following the questionnaire, with optimal glycaemic control defined≥80% values meeting the targets<5.3mmol/L for fasting and <7.8mmol/L 1-hour after meals. Logistic regression estimated the odds of achieving optimal control; linear regression estimated activity level-specific least square mean glucose, as well as between-level mean glucose differences.

RESULTS

For volume of moderate intensity sports and exercise ([MET×hours]/week), the highest quartile, compared to the lowest, had significantly increased odds of optimal control (OR=1.82 [95% CI: 1.06-3.14] P=0.03). There were significant trends for decreasing mean 1-hour post breakfast, lunch and dinner glycaemia with increasing quartile of moderate activity (all P<0.05). Any participation in vigorous intensity sports and exercise was associated with decreased mean 1-hour post breakfast and lunch glycaemia (both P<0.05). No associations were observed for fasting.

CONCLUSION

Higher volumes of moderate intensity sports and exercise, reported shortly after GDM diagnosis, were significantly associated with increased odds of achieving glycaemic control. Clinicians should be aware that unsupervised moderate intensity sports and exercise performed in mid-pregnancy aids in subsequent glycaemic control among women with GDM.

Rationale for treatment options for mealtime glucose control in patients with type 2 diabetes

While glycemic control is routinely assessed using HbA1c and fasting glucose measures, postprandial glucose (PPG) is also an important contributor of overall glycemia. Furthermore, PPG excursions have been linked to complications of diabetes. This review examines the effects of glucose-lowering therapies (including treatments administered at mealtime) on postprandial hyperglycemia in patients with type 2 diabetes. A PubMed search was conducted to identify clinical studies of treatments for mealtime glucose control in type 2 diabetes. Different treatments may have comparable effects on HbA1c but varying effects on PPG control and glucose fluctuations. Older classes of oral glucose-lowering treatments administered at mealtime to lower PPG include meglitinides and α-glucosidase inhibitors. Injectable therapies, including prandial insulin analogs, glucagon-like peptide-1 receptor agonists (GLP-1RAs), and the amylin analog pramlintide, all effectively target postprandial hyperglycemia. Compared with longer-acting GLP-1RAs, short-acting GLP-1RAs, such as exenatide twice daily and lixisenatide once daily, have a greater effect on PPG control, which is primarily mediated by a more pronounced effect on delayed gastric emptying. Dipeptidyl peptidase-4 inhibitors and sodium-glucose cotransporter 2 inhibitors also reduce postprandial hyperglycemia. To achieve more physiologically normal glycemic control, choice of therapy should ideally aim to address daily glucose fluctuations, including hyperglycemic peaks and hypoglycemic troughs, and long-term glycemic control.

High-intensity aerobic interval training improves aerobic fitness and HbA1c among persons diagnosed with type 2 diabetes

PURPOSE

It remains to be established how high-intensity aerobic interval training (HAIT) affects risk factors associated with type 2 diabetes (TD2). This study investigated effects of HAIT on maximal oxygen uptake (VO_2max), glycated Hemoglobin type A1C (HbA1c), insulin resistance (IR), fat oxidation (FatOx), body weight (BW), percent body fat (%BF), lactate threshold (LT), blood pressure (BP), and blood lipid profile (BLP) among persons with T2D. Results were compared to the effects after a moderate-intensity training (MIT) program.

METHODS

Thirty-eight individuals with T2D completed 12 weeks of supervised training. HAIT consisted of 4 × 4 min of walking or running uphill at 85-95% of maximal heart rate, and MIT consisted of continuous walking at 70-75% of maximal heart rate.

RESULTS

A 21% increase in VO_2max (from 25.6 to 30.9 ml kg^-1 min^-1, p < 0.001), and a reduction in HbA1c by -0.58% points (from 7.78 to 7.20%, p < 0.001) was found in HAIT. BW and body mass index (BMI) was reduced by 1.9% (p < 0.01). There was a tendency towards an improved FatOx at 60% VO_2max (14%, p = 0.065). These improvements were significant different from MIT. Both HAIT and MIT increased velocity at LT, and reduced %BF, waist circumference, hip circumference, and BP, with no significant differences between the two groups. Correlations were found between change in VO_2max and change in HbA1c when the two intervention groups were combined (R = -0.52, p < 0.01).

CONCLUSION

HAIT is an effective exercise strategy to improve aerobic fitness and reduce risk factors associated with T2D.