Pancreatic function, type 2 diabetes, and metabolism in aging

The impact of taxing sugar-sweetened beverages on diabetes: a critical review

The global burden of type 2 diabetes is increasing at an alarming rate, fuelled by the obesity epidemic, with significant associated health and economic consequences and apparent inequalities. Sugar-sweetened beverages (SSBs) are a major source of added sugars in diets worldwide and have been linked to an increased risk of type 2 diabetes through a variety of mechanisms, including excess weight. Taxing SSBs has become a promising public health strategy to reduce consumption and mitigate the burden of type 2 diabetes. A substantial body of evidence suggests that SSB taxes lead to increased prices and subsequent reduced consumption, with a potentially greater effect among lower socioeconomic groups. This highlights the potential for tax policies to have an impact on type 2 diabetes and address health inequalities. Evidence from several ongoing SSB tax schemes, including sales and excise taxes, indicates positive effects on improving consumption patterns, and modelling studies point to health gains by averting type 2 diabetes and other cardiometabolic diseases. In contrast, evidence from empirical evaluation of the impact of SSB tax is scarce. Continued monitoring and the strengthening of evaluation research to develop context-tailored policies are required. In addition, there is a need to implement complementary efforts to amplify the impact of SSB taxation and effectively address the global burden of type 2 diabetes.

Investigation of Pancreatic-beta Cells Role in the Biological Process of Ageing

BACKGROUND

Cellular senescence is associated with the formation and progression of a range of illnesses, including ageing and metabolic disorders such as diabetes mellitus and pancreatic beta cell dysfunction. Ageing and reduced glucose tolerance are interconnected. Often, Diabetes is becoming more common, which is concerning since it raises the risk of a variety of age-dependent disorders such as cardiovascular disease, cancer, Parkinson's disease, stroke, and Alzheimer's disease.

OBJECTIVES

The objectives of this study are to find out the most recent research on how ageing affects the functions of pancreatic beta cells, beta cell mass, beta cell senescence, mitochondrial dysfunction, and hormonal imbalance.

METHODS

Various research and review manuscripts are gathered from various records such as Google Scholar, PubMed, Mendeley, Scopus, Science Open, the Directory of Open Access Journals, and the Education Resources Information Centre, using different terms like "Diabetes, cellular senescence, beta cells, ageing, insulin, glucose".

RESULTS

In this review, we research novel targets in order to discover new strategies to treat diabetes. Abnormal glucose homeostasis and type 2 diabetes mellitus in the elderly may aid in the development of novel medicines to delay or prevent diabetes onset, improve quality of life, and, finally, increase life duration.

CONCLUSION

Aging accelerates beta cell senescence by generating premature cell senescence, which is mostly mediated by high glucose levels. Despite higher plasma glucose levels, hepatic gluconeogenesis accelerates and adipose tissue lipolysis rises, resulting in an increase in free fatty acid levels in the blood and worsening insulin resistance throughout the body.

Association between traffic-related air pollution and osteoporotic fracture hospitalizations in inland and coastal areas: evidences from the central areas of two cities in Shandong Province, China

Our result showed that short-term exposure to traffic-related air pollutants (TRAPs) might increase the risk of hospitalizations for osteoporotic fractures. It was suggested that government should formulate emission reduction policies to protect the health of citizens.

INTRODUCTION

As the main source of urban air pollution in China, exhaust emissions of motor vehicles have been linked to adverse health outcomes, but evidence of the relationship between short-term exposure to TRAPs and osteoporotic fractures is still relatively rare.

METHODS

In this study, a total of 5044 inpatients from an inland city (Jinan) and a coastal city (Qingdao), two cities with developed transportation in Shandong Province, were included. A generalized additive model (GAM) was used to investigate the association between TRAPs and hospitalizations for osteoporotic fractures. The stratified analyses were performed by gender and age.

RESULTS

Positive associations between TRAPs and osteoporotic fracture hospitalizations were observed. We found that short-term exposure to TRAPs was associated with increased numbers of hospitalizations for osteoporotic fractures. PM2.5 and PM10 were statistically significant associated with hospitalizations for osteoporotic fractures at both single-day and multiday lag structures only in Qingdao, with the strongest associations at lag06 and lag07 [RR=1.0446(95%CI: 1.0018,1.0891) for PM2.5, RR=1.0328(95%CI: 1.0084,1.0578) for PM10]. For NO2 and CO, we found significant associations at lag4 in the single lag structure in Jinan [RR=1.0354 (95%CI: 1.0071, 1.0646) for NO2, RR=1.0014 (95%CI: 1.0002, 1.0025) for CO], while only CO at lag4 was significantly associated with hospitalizations for osteoporotic fractures in Qingdao [1.0038 (1.0012, 1.0063)]. Stratified analyses indicated that the associations were stronger in females and older individuals (65 + years).

CONCLUSION

This study implied that short-term exposure to TRAPs pollution was associated with an increased risk of hospitalizations for osteoporotic fractures. Female patients and patients aged 65 + years appeared to be more vulnerable to TRAPs, suggesting that poor air quality is a modifiable risk factor for osteoporotic fractures.

Changes in Pancreatic Senescence Mediate Pancreatic Diseases

In recent years, there has been a significant increase in age-related diseases due to the improvement in life expectancy worldwide. The pancreas undergoes various morphological and pathological changes with aging, such as pancreatic atrophy, fatty degeneration, fibrosis, inflammatory cell infiltration, and exocrine pancreatic metaplasia. Meanwhile, these may predispose the individuals to aging-related diseases, such as diabetes, dyspepsia, pancreatic ductal adenocarcinoma, and pancreatitis, as the endocrine and exocrine functions of the pancreas are significantly affected by aging. Pancreatic senescence is associated with various underlying factors including genetic damage, DNA methylation, endoplasmic reticulum (ER) stress, mitochondrial dysfunction, and inflammation. This paper reviews the alternations of morphologies and functions in the aging pancreas, especially β-cells, closely related to insulin secretion. Finally, we summarize the mechanisms of pancreatic senescence to provide potential targets for treating pancreatic aging-related diseases.

Prevalence of Non-Alcoholic Fatty Liver Disease (NAFLD) in Korean Patients Undergoing Bariatric Surgery

Purpose

The number of Korean patients undergoing metabolic surgery for obesity is on the increase. Patients undergoing obesity and metabolic surgery have a body mass index (BMI) ≥30 kg/m². In this study, we investigated the prevalence of nonalcoholic fatty liver disease in Korean patients who had undergone bariatric surgery.

Materials and Methods

Between January 2019 and December 2021, 147 patients who underwent bariatric surgery were studied. Of these, 133 patients underwent transient elastography, and the prevalence was analyzed after being classified using the World Health Organization (WHO) obesity classification system. The participants were divided into three groups as Class 1, BMI 30 to <35 kg/m²; Class 2, BMI 35 to <40 kg/m²; and Class 3, BMI ≥40 kg/m²).

Results

The average ages of three classes of patients according to the WHO obesity classification system were 42.4, 38.8, and 36.0 years with intergroup differences. Controlled attenuation parameter (CAP) and liver stiffness also showed differences in each group (307.6±59.3, 325.8±53.0, and 346.5±52.2, respectively, P=0.007; CAP, 5.5±2.1, 7.1±3.8, and 11.7±9.1, P<0.001; liver stiffness). The prevalence of type 2 diabetes mellitus also differed among the groups (61.3%, 42.2%, and 36.8%, respectively, P=0.036). The proportion of patients with liver fibrosis also showed differences in each group (16.1%, 42.2%, and 59.6%, respectively; P<0.001).

Conclusion

Our study shows that most Korean patients undergoing bariatric surgery were also diagnosed with hepatic steatosis. Furthermore, the rate of liver fibrosis was higher among patients with more severe obesity.

Inhibition of glutaminolysis restores mitochondrial function in senescent stem cells

Mitochondrial dysfunction, a hallmark of aging, has been associated with the onset of aging phenotypes and age-related diseases. Here, we report that impaired mitochondrial function is associated with increased glutamine catabolism in senescent human mesenchymal stem cells (MSCs) and myofibroblasts derived from patients suffering from Hutchinson-Gilford progeria syndrome. Increased glutaminase (GLS1) activity accompanied by loss of urea transporter SLC14A1 induces urea accumulation, mitochondrial dysfunction, and DNA damage. Conversely, blocking GLS1 activity restores mitochondrial function and leads to amelioration of aging hallmarks. Interestingly, GLS1 expression is regulated through the JNK pathway, as demonstrated by chemical and genetic inhibition. In agreement with our in vitro findings, tissues isolated from aged or progeria mice display increased urea accumulation and GLS1 activity, concomitant with declined mitochondrial function. Inhibition of glutaminolysis in progeria mice improves mitochondrial respiratory chain activity, suggesting that targeting glutaminolysis may be a promising strategy for restoring age-associated loss of mitochondrial function.

Mendelian randomization study of obesity and type 2 diabetes in hospitalized COVID-19 patients

BACKGROUND

Both obesity and type 2 diabetes (T2D) are reported to be highly enriched in hospitalized COVID-19 patients. Due to the close correlation between obesity and T2D, it is important to examine whether obesity and T2D are independently related to COVID-19 hospitalization.

OBJECTIVE

To examine the causal effect of obesity and T2D in hospitalized COVID-19 patients using Mendelian randomization (MR).

RESEARCH DESIGN AND METHODS

This two-sample MR analysis applied genetic markers of obesity identified in the genome wide association study (GWAS) by the GIANT Consortium as instrumental variables (IVs) of obesity; and genetic markers of T2D identified by the DIAGRAM Consortium as IVs of T2D. The MR analysis was performed in hospitalized COVID-19 patient by the COVID-19 Host Genetics Initiative using the MR-Base platform.

RESULTS

All 3 classes of obesity (Class 1/2/3) were shown as the causal risk factors of COVID-19 hospitalization; however, T2D doesn't increase the risk of hospitalization or critically ill COVID-19 as an independent factor.

CONCLUSIONS

Obesity, but not T2D, is a primary risk factor of COVID-19 hospitalization.

REM Sleep Deprivation Impairs Learning and Memory by Decreasing Brain O-GlcNAc Cycling in Mouse

Rapid eye movement (REM) sleep is implicated learning and memory (L/M) functions and hippocampal long-term potentiation (LTP). Here, we demonstrate that REM sleep deprivation (REMSD)-induced impairment of contextual fear memory in mouse is linked to a reduction in hexosamine biosynthetic pathway (HBP)/O-GlcNAc flux in mouse brain. In mice exposed to REMSD, O-GlcNAcylation, and O-GlcNAc transferase (OGT) were downregulated while O-GlcNAcase was upregulated compared to control mouse brain. Foot shock fear conditioning (FC) induced activation of protein kinase A (PKA) and cAMP response element binding protein (CREB), which were significantly inhibited in brains of the REMSD group. Intriguingly, REMSD-induced defects in L/M functions and FC-induced PKA/CREB activation were restored upon increasing O-GlcNAc cycling with glucosamine (GlcN) or Thiamet G. Furthermore, Thiamet G restored the REMSD-induced decrease in dendritic spine density. Suppression of O-GlcNAcylation by the glutamine fructose-6-phosphate amidotransferase (GFAT) inhibitor, 6-diazo-5-oxo-L-norleucine (DON), or OGT inhibitor, OSMI-1, impaired memory function, and inhibited FC-induced PKA/CREB activation. DON additionally reduced the amplitude of baseline field excitatory postsynaptic potential (fEPSP) and magnitude of long-term potentiation (LTP) in normal mouse hippocampal slices. To our knowledge, this is the first study to provide comprehensive evidence of dynamic O-GlcNAcylation changes during the L/M process in mice and defects in this pathway in the brain of REM sleep-deprived mice. Our collective results highlight HBP/O-GlcNAc cycling as a novel molecular link between sleep and cognitive function.

Fish Oil for Healthy Aging: Potential Application to Master Athletes

Master athletes perform high volumes of exercise training yet display lower levels of physical functioning and exercise performance when compared with younger athletes. Several reports in the clinical literature show that long chain n-3 polyunsaturated fatty acid (LC n-3 PUFA) ingestion promotes skeletal muscle anabolism and strength in untrained older persons. There is also evidence that LC n-3 PUFA ingestion improves indices of muscle recovery following damaging exercise in younger persons. These findings suggest that LC n-3 PUFA intake could have an ergogenic effect in master athletes. However, the beneficial effect of LC n-3 PUFA intake on skeletal muscle in response to exercise training in both older and younger persons is inconsistent and, in some cases, generated from low-quality studies or those with a high risk of bias. Other factors such as the choice of placebo and health status of participants also confound interpretation of existing reports. As such, when considered on balance, the available evidence does not indicate that ingestion of LC n-3 PUFAs above current population recommendations (250–500 mg/day; 2 portions of oily fish per week) enhances exercise performance or recovery from exercise training in master athletes. Further work is now needed related to how the dose, duration, and co-ingestion of LC n-3 PUFAs with other nutrients such as amino acids impact the adaptive response to exercise training. This work should also consider how LC n-3 PUFA supplementation may differentially alter the lipid profile of cellular membranes of key regulatory sites such as the sarcolemma, mitochondria, and sarcoplasmic reticulum.

Pharmacological Treatment of Sarcopenia

Sarcopenia has been acquiring a growing importance in the scientific literature and in doctors' offices. As the population ages, it becomes increasingly essential to know, prevent, and treat this clinical condition. The purpose of the present review is to bring up the current evidence on the diagnosis of this pathology, in a practical way, as well as the main current treatment options.

Comparision of Low and High Volume of Resistance Training on Body Fat and Blood Biomarkers in Untrained Older Women: A Randomized Clinical Trial

ABSTRACT

Cunha, PM, Tomeleri, CM, Nascimento, MA, Mayhew, JL, Fungari, E, Cyrino, LT, Barbosa, DS, Venturini, D, and Cyrino, ES. Comparision of low and high volume of resistance training on body fat and blood biomarkers in untrained older women: a randomized clinical trial. J Strength Cond Res 35(1): 1-8, 2021-The purpose of this study was to compare the effects of resistance training (RT) performed with 2 different volumes on body fat and blood biomarkers in untrained older women. Sixty-five physically independent older women (≥60 years) were randomly assigned to one of 3 groups: low-volume (LV) training group, high-volume (HV) training group, and a control group. Both training groups performed RT for 12 weeks, using 8 exercises of 10-15 repetitions maximum for each exercise. The low-volume group performed only a single set per exercise, whereas the HV group performed 3 sets. Anthropometric, body fat (%), trunk fat, triglycerides (TG), total cholesterol, low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol, very LDL-c (VLDL-c), glucose (GLU), C-reactive protein (CRP), and composite Z-score were measured. The HV group obtained greater improvements compared with the LV group (p < 0.05) for TG (LV = -10.5% vs. HV = -16.6%), VLDL-c (LV = -6.5% vs. HV = -14.8%), GLU (LV = -4.7% vs. HV = -11.1%), CRP (LV = -13.2% vs. HV = -30.8%), % body fat (LV = -2.4% vs. HV = -6.1%), and composite Z-score (LV = -0.13 ± 0.30 vs. HV = -0.57 ± 0.29). Trunk fat was reduced (p < 0.05) only in the HV group (-6.8%). We conclude that RT performed in higher volume seems to be the most appropriate strategy to reduce body fat (%), trunk fat, improve blood biomarkers, and reduce composite Z-score in older women.

Transplantation of IL-10-Overexpressing Bone Marrow-Derived Mesenchymal Stem Cells Ameliorates Diabetic-Induced Impaired Fracture Healing in Mice

Background

Diabetes mellitus is characterized by hyperglycemia which displays insufficiency or resistance to insulin. One of the complications of diabetes is the increased risk of fracture and the impairment of bone repair and regulation. There have been evidences from previous studies that mesenchymal stem cells (MSCs) from bone marrow promote cartilage and callous formation. In addition, IL-10, an anti-inflammatory cytokine, has been observed to relieve inflammation-related complications in diabetes.

Methods

In this study, the role of IL-10-overexpressing bone marrow-derived MSCs (BM-MSCs) was examined in the diabetic mice model with femur fracture. MSCs were isolated from the BALB/c mice and IL-10 over expression was conducted with lentivirus transduction. The streptozotocin (STZ)-induced diabetes model with femoral fracture was established. BM-MSCs with IL-10 over expression were transplanted into the fracture area. The expressions of inflammatory factors IL-6, TNF-α and INF-γ were examined by qPCR and immunoblot; the biomechanical strength of the fracture site of the mice was examined and evaluated.

Results

Data showed that IL-10 overexpressed BM-MSCs transplantation decreased inflammatory response, promoted bone formation, and increased the strength of the fracture site in STZ-induced diabetic mice with femoral fracture.

Conclusion

IL-10 overexpressed BM-MSCs transplantation accelerated fracture repair in STZ-induced diabetic mice, which in turn provides potential clinical application prospects.

The antidiabetic and hepatoprotective effects of myricitrin on aged mice with D-galactose

AIM

The present study aims to evaluate the effects of antidiabetic and hepatoprotective of myricitrin in the aged mice induced by D-galactose (D-gal).

BACKGROUND

Aging occurs during a person's life; there has been no way to stop the aging process, but antioxidant and changing lifestyles can delay it.

METHODS

In this experimental study, 72 female adult mice (weighing30-35g) were randomly divided into six groups: 1: control, 2: D-gal at 500mg/kg/d, 3-5: D-gal+ Myricitrin at 5, 10 and 20mg/kg/d 6: D-gal+ Vitamin E at 100mg/kg/d. Aging induced by D-gal for 45 days via intraperitoneal. Myricitrin and Vitamin E administrated orally by gavage for the last 28 days. The blood glucose, insulin level, β-cell function, insulin resistance, hepatic enzymes, lipid profile, and histology of the liver, and pancreas were evaluated.

RESULTS

D-gal injection increased the glucose (p<0.001) and insulin levels (p<0.01) compared to control group. Myricitrin (p<0.01) and Vitamin E (p<0.001) increased insulin and decreased blood glucose levels compared to D-gal group. Myricitrin had a similar impact on insulin levels to vitamin E. Insulin resistance induced in the D-gal group (p<0.001). Myricitrin reduced insulin resistance and increased β-cell function (p<0.01) compared to D-gal group. D-gal elevated (p<0.01) cholesterol, LDL and triglyceride level, myricitrin (p<0.001), and Vitamin E (p<0.05) were reduced.

CONCLUSION

D-gal-induced aging causes the accumulation of RBCs, inflammation in the liver, and changes in the number and diameter of Langerhans islets in the pancreas. Myricitrin improved these D-gal effects. Myricitrin had the anti-diabetic and hepatoprotective effects on the aged mice induced by D-galactose.

Pharmacists Intervention Reduced Drug-Related Problems in the Treatment of Patients with Type 2 Diabetes Mellitus

BACKGROUND:

Type 2 Diabetes Mellitus (T2DM) remains as a global public health problem, including Indonesia due to its continuous increasing prevalence.

AIM:

To analyze the impact of pharmacist intervention on drug-related problems (DRPs) occurred in the management of patients with T2DM admitted to Tebing Tinggi Hospital (TTH), Indonesia, period March through August 2018.

METHODS:

This six-month retrospective prospective cohort study evaluated the impact of pharmacist intervention on the occurrence of DRPs in the management of patients with T2DM (n = 45) insured by Social Security Organizing Body in TTH, North Sumatera, Indonesia. The inclusion criteria were T2DM patients with age ≥ 18 years and under treatment of antidiabetic drugs. A questionnaire was used to assess the characteristics of the patients and antidiabetic drugs provided. The incidence of DRPs in groups with usual care for the previous three-month and with pharmacist interventions for the next three-month admissions were analyzed using Pharmaceutical Care Network Europe (PCNE) DRP classification system version 8.01 that consists of 3 primary domains for problems, 8 primary domains for causes, and 5 primary domains (PCNE, 2017) and trustable literatures. The obtained data were analyzed using descriptive statistics and paired t test in the program of Statistical Package for the Social Sciences version 19 (p < 0.05 was considered significant).

RESULTS:

Most (66.7%) of the patients were female. Their mean age was 61.96 ± 6.45 (years). The three most widely provided drugs were metformin, glimepirid, and gliclazide. Total incidence of DRPs in groups with: usual care, 128; intervention, 39. There was a significant difference between the incidence of DRPs in groups with usual care and intervention, p ≤ 0.001.

CONCLUSION:

Pharmacist intervention reduced the incidence of DRPs in the management of T2DM patients.

Failed Recovery of Glycemic Control and Myofibrillar Protein Synthesis With 2 wk of Physical Inactivity in Overweight, Prediabetic Older Adults

Background

Physical inactivity impairs insulin sensitivity, which is exacerbated with aging. We examined the impact of 2 wk of acute inactivity and recovery on glycemic control, and integrated rates of muscle protein synthesis in older men and women.

Methods

Twenty-two overweight, prediabetic older adults (12 men, 10 women, 69 ± 4 y) undertook 7 d of habitual activity (baseline; BL), step reduction (SR; <1,000 steps.d-1 for 14 d), followed by 14 d of recovery (RC). An oral glucose tolerance test was used to assess glycemic control and deuterated water ingestion to measure integrated rates of muscle protein synthesis.

Results

Daily step count was reduced (all p < .05) from BL at SR (7362 ± 3294 to 991 ± 97) and returned to BL levels at RC (7117 ± 3819). Homeostasis model assessment-insulin resistance increased from BL to SR and Matsuda insulin sensitivity index decreased and did not return to BL in RC. Glucose and insulin area under the curve were elevated from BL to SR and did not recover in RC. Integrated muscle protein synthesis was reduced during SR and did not return to BL in RC.

Conclusions

Our findings demonstrate that 2 wk of SR leads to lowered rates of muscle protein synthesis and a worsening of glycemic control that unlike younger adults is not recovered during return to normal activity in overweight, prediabetic elderly humans.

Clinical Trials Registration

ClinicalTrials.gov identifier: NCT03039556.

Inhibition of the sodium-glucose co-transporter 2 in the elderly: clinical and mechanistic insights into safety and efficacy

The prevalence of type 2 diabetes mellitus (T2DM) in the elderly grew sharply over the last decade. Reduced insulin sensitivity and secretory capacity, weight gain, sarcopenia, and elevated adiposity are all common metabolic and body changes in the aging population that favor an increased risk of hypoglycemia, frailty syndrome, falls, and cognitive dysfunction. First line antidiabetic therapy is frequently not safe in older individuals because of its high risk of hypoglycemia and prevalent co-morbid diseases, such as chronic kidney disease, osteoporosis, cardiovascular disease, and obesity. Sodium-glucose cotransporter 2 inhibitor (SGLT2i) is a new class of antidiabetic therapy that inhibits glucose and sodium reabsorption on renal proximal convoluted tubule. Its effect is well demonstrated in various clinical scenarios in the younger population. This review and metanalysis describe particularities of the SGLT2i on the elderly, with mechanistic insights of the potential benefit and remaining challenges about the use of these drugs in this important age group. Further, we will present a meta-analysis of the main effects of SGLT2i reported in post-hoc studies in which the median age of the subgroups analyzed was over 60 years. Despite the absence of specific clinical trials for this population, our findings suggest that SGLT2i therapy on older individuals is effective to lower glucose and maintain its effect on systolic blood pressure and body weight.

The effects of inflammation, aging and oxidative stress on the pathogenesis of diabetes mellitus (type 2 diabetes)

Diabetes mellitus is seen to be prevalent among the different epidemics. The prevalence rate of the diabetes mellitus is seen to be increasing in different regions of the world. Type 2 diabetes mellitus is the most common form of the disease that causes the defect in the production of insulin. It is associated with the disruption in the metabolism of fat, proteins and carbohydrates. Different complications that are associated with T2DM includes the retinopathy, neuropathy, nephropathy and weakness and other issues. Due to the loss of the function of the insulin, the metabolism is disturbed. . It is needed to consider the effects of inflammation aging and the oxidative stress on the diabetes mellitus. Therefore this review has dealt with this particular issue in great detail. The predominant aim of this review was to evaluate the effects of inflammation aging and oxidative stress on the T2DM. It was achieved through correlating and comparing the studies of different researchers. This review article has reviewed this topic in great detail considering the different researches related to the inflammation aging, oxidative stress and their impact on the diabetes mellitus.

Protocol for systematic review and meta-analysis of sex hormones and diabetes risk in ageing men and women of African ancestry

AIM

To present the protocol of a systematic review and meta-analysis of the available evidence examining the association between sex hormones and type 2 diabetes risk in ageing men and women of African descent.

METHODS

We shall conduct a comprehensive search of published studies that examined the association between sex hormones and type 2 diabetes risk in men and women aged ≥40 years from 01/01/1980 to 31/03/2018 with no language restriction. Databases to be searched include: PubMed, Scopus, Cochrane Library, Cumulative Index to Nursing and Allied Health, ISI Web of Science, Clinical Trial registries, Google Scholar and institutional websites such as the WHO, American Diabetes Association, International Diabetes Federation, World Diabetes Foundation, European Association for the Study of Diabetes, African Journal Online and ProQuest databases. This protocol is developed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols guidelines. Independent screening for eligible studies using defined criteria and data extraction, will be completed in duplicate. Discrepancies will be resolved by consensus or consultation with a third researcher. Risk of bias of included studies will be assessed by the appropriate Cochrane risk of bias tool. The overall association estimates will be pooled using appropriate meta-analytic techniques. Heterogeneity will be assessed using Cochrane Q statistic and the inconsistency index (I2). The random effects model will be used to calculate a pooled estimate.

ETHICS AND DISSEMINATION

No ethics clearance is required as no primary data will be collected. The systematic review and meta-analysis are part of a PhD project at WITS University (Johannesburg, South Africa) and results will be presented at conferences and published in a peer-review journal. The results will guide future population specific interventions.

PROSPERO REGISTRATION NUMBER

CRD42017074581.

Effect of New-Onset Diabetes Mellitus on Renal Outcomes and Mortality in Patients with Chronic Kidney Disease

Background: The incidence rates of diabetes mellitus (DM) and chronic kidney disease (CKD) are increasing worldwide and their coexistence can have a large negative impact on clinical outcomes. However, it is unclear how incident DM affects CKD patients. Methods: Incident CKD patients between 2000 and 2013 were identified from the National Health Insurance Research Database of Taiwan; they were classified as non-DM (n = 10,356), pre-existing DM (n = 6982), and incident DM (n = 1103). Non-DM cases were patients who did not develop DM before the end of the observation period. The outcomes of interest were end-stage renal disease (ESRD), mortality, and composite outcome (ESRD or death). The association between the DM groups and clinical outcomes was estimated using the inverse probability of group-weighted (IPW) multivariate-adjusted time-dependent Cox regression models. Results: During the study period of 14 years, 1735 (16.6%) patients in the non-DM group reached ESRD compared with 2168 (31.05%) in the pre-existing DM group and 111 (11.03%) in the incident DM group (p < 0.001). Moreover, 2219 (21.43%) patients in the non-DM group died compared with 1895 (27.14%) in the pre-existing DM group and 303 (27.47%) in the incident DM group (p < 0.001). Compared with the non-DM group, the pre-existing DM group was associated with a higher risk of ESRD [hazard ratio (HR) 2.54; 95% confidence interval (CI 2.43–2.65), death (HR 2.23; 95% CI 2.14–2.33), and a composite outcome (HR 2.29; 95% CI 2.21–2.36). Similarly, incident DM was also associated with a higher risk of ESRD (HR 1.12; 95% CI 1.06–1.19), death (HR 2.48; 95% CI 2.37–2.60), and a composite outcome (HR 1.77; 95% CI 1.70–1.84) compared with the non-DM group. Factors contributing to incident DM included old age, low monthly income, and having hypertension, hyperlipidemia, and ischemic heart disease, while pentoxifylline reduced the risk of incident DM. Conclusion: Similarly to pre-existing DM, CKD patients with incident DM carried a higher risk of ESRD, mortality, and a composite outcome compared with those with non-DM. For those at risk of incident DM, strict monitoring and intervention strategies must be adopted to help improve their clinical outcomes.

Characterization of glucose-stimulated insulin release protocols in african green monkeys (Chlorocebus aethiops)

Background

Management of diabetes remains a major health and economic challenge, demanding test systems in which to develop new therapies. These studies assessed different methodologies for determining glucose tolerance in green monkeys.

Methods

Twenty‐eight African green monkeys between 4 and 24 years old underwent single or repeat intravenous glucose tolerance testing (IVGTT), oral glucose tolerance testing (OGTT), and/or graded glucose infusion testing.

Results

Geriatric monkeys exhibited glucose intolerance with impaired glucose‐stimulated insulin secretion following IVGTT. Repeat IVGTT and OGTT assessments were inconsistent. Monkeys with low glucose‐stimulated insulin secretion after graded glucose infusion exhibited elevated blood glucose levels.

Conclusion

IVGTT and graded glucose infusion protocols revealed differences in glucose tolerance among green monkeys at single time points, including age‐dependent differences suggestive of shifts in pancreatic beta‐cell functional capacity, but care should be applied to study design and the interpretation of data in the setting of longitudinal studies.

Lipidomic profiling of targeted oxylipins with ultra-performance liquid chromatography-tandem mass spectrometry

Oxylipins are bioactive mediators that play diverse roles in (patho)physiology. We developed a sensitive and selective ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous profiling of 57 targeted oxylipins derived from five major n-6 and n-3 polyunsaturated fatty acids (PUFAs) that serve as oxylipin precursors, including linoleic (LA), arachidonic (AA), alpha-linolenic (ALA), eicosapentaenoic (EPA), and docosahexaenoic (DHA) acids. The targeted oxylipin panel provides broad coverage of lipid mediators and pathway markers generated from cyclooxygenases, lipoxygenases, cytochrome P450 epoxygenases/hydroxylases, and non-enzymatic oxidation pathways. The method is based on combination of protein precipitation and solid-phase extraction (SPE) for sample preparation, followed by UPLC-MS/MS. This is the first methodology to incorporate four hydroxy-epoxy-octadecenoic acids and four keto-epoxy-octadecenoic acids into an oxylipin profiling network. The novel method achieves excellent resolution and allows in-depth analysis of isomeric and isobaric species of oxylipin extracts in biological samples. The method was quantitatively characterized in human plasma with good linearity (R = 0.990-0.999), acceptable reproducibility (relative standard deviation (RSD) < 20% for the majority of analytes), accuracy (67.8 to 129.3%) for all analytes, and recovery (66.8-121.2%) for all analytes except 5,6-EET. Ion enhancement effects for 28% of the analytes in tested concentrations were observed in plasma, but were reproducible with RSD < 17.2%. Basal levels of targeted oxylipins determined in plasma and serum are in agreement with those previously reported in literature. The method has been successfully applied in clinical and preclinical studies.

Cellular Senescence, Neurological Function, and Redox State

SIGNIFICANCE

Cellular senescence, characterized by permanent cell cycle arrest, has been extensively studied in mitotic cells such as fibroblasts. However, senescent cells have also been observed in the brain. Even though it is recognized that cellular energetic metabolism and redox homeostasis are perturbed in the aged brain and neurodegenerative diseases (NDDs), it is still unknown which alterations in the overall physiology can stimulate cellular senescence induction and their relationship with the former events. Recent Advances: Recent findings have shown that during prolonged inflammatory and pathologic events, the blood-brain barrier could be compromised and immune cells might enter the brain; this fact along with the brain's high oxygen dependence might result in oxidative damage to macromolecules and therefore senescence induction. Thus, cellular senescence in different brain cell types is revised here.

CRITICAL ISSUES

Most information related to cellular senescence in the brain has been obtained from research in glial cells since it has been assumed that the senescent phenotype is a feature exclusive to mitotic cells. Nevertheless, neurons with senescence hallmarks have been observed in old mouse brains. Therefore, although this is a controversial topic in the field, here we summarize and integrate the observations from several studies and propose that neurons indeed senesce.

FUTURE DIRECTIONS

It is still unknown which alterations in the overall metabolism can stimulate senescence induction in the aged brain, what are the mechanisms and signaling pathways, and what is their relationship to NDD development. The understanding of these processes will expose new targets to intervene age-associated pathologies.-Antioxid. Redox Signal. 28, 1704-1723.

Regulation of aging and oxidative stress pathways in aged pancreatic islets using alpha-lipoic acid

Oxidative stress has been involved in the aging process and the pathogenesis of type-2 diabetes, which is a serious health problem worldwide. This study investigates the anti-aging, anti-apoptotic, and antioxidant properties of alpha-lipoic acid (ALA), aiming to improve aged rat pancreatic cells. In this regard, half maximal effective concentration (EC₅₀) of ALA based on the survival of aged pancreatic islet cells was determined as 100 µM. Following this, p38 and p53 genes expression as key factors in aging, oxidative stress biomarkers, insulin secretion, and Pdx1 protein expression were evaluated using real-time PCR, ELISA reader, and fluorescence microscope. It was revealed that ALA reduces and controls the effects of aging on beta cells mainly by suppressing p38 and p53 at the gene level (P < 0.001 and P < 0.01), respectively, reducing reactive oxygen species (P < 0.001) and enhancing levels of thiols (P < 0.05) compared with the aged islets. Furthermore, both qualitative and quantitative investigations of insulin secretion have shown that ALA can improve aged cells' function and increase insulin secretion specially in the stimulating concentration of glucose. Also, the expression of Pdx1 was considerably increased by ALA in comparison to the aged pancreatic islets (P < 0.001). As far as the authors of the present study are concerned, this is the first study, which evaluated aging associated with p38 and p53 pathways, oxidative stress parameters, and the expression of insulin in beta cells of an aged rat and reaffirmed the fact that ALA has a significant antioxidant role in reducing the aging process.

Cigarette Smoking and Hyperglycaemia in Diabetic Patients

BACKGROUND:

The incidence rate of diabetes mellitus has increased throughout the year. Various studies indicate that smoking may affect glucose metabolism and cause hyperglycemia in diabetes mellitus. This study aimed to compare the blood glucose and HbA1c level in diabetic smoking patients and non-smoking diabetic patients.

METHODS:

This study used the cross-sectional approach. The study population consisted of 30 diabetic smoking patients and 30 non-smoking diabetic patients. The diabetes history and the smoking status of the study population obtained by questionnaire-based interview, the blood glucose and HbA1c level were measured by hexokinase and immunoturbidimetry method using cobas 6000 analyser module c501 (Roche Diagnostics, Switzerland).

RESULTS:

The result in this study showed the fasting blood glucose, postprandial blood glucose, and HbA1c were higher by 23.64 mg/dl (p = 0.325), 58.00 mg/dl (p = 0.016), 0.39% (p = 0.412) in smoking diabetic patients compared to non-smoking diabetic patients. After statistical analysis, there was a significant difference (p < 0.05) of postprandial glucose level between smokers group and non-smokers group, but the non-significant difference of fasting blood glucose and HbA1c

CONCLUSIONS:

This study concluded that there was a significant difference in postprandial glucose level between smokers group and non-smokers group but the non-significant difference of fasting blood glucose and HbA1c.

Association between Socioeconomic Status and Diabetes Mellitus: The National Socioeconomics Survey, 2010 and 2012

INTRODUCTION

The prevalence of Diabetes Mellitus (DM) is increasing, globally. However, studies on the association between Socioeconomic Status (SES) factors and DM have mostly been conducted in specific areas with rather small sample sizes or not with nationally representative samples. Their results have also been inconclusive regarding whether SES has any influence on DM or not.

AIM

To determine the association between SES and DM in Thailand.

MATERIALS AND METHODS

This study utilized the data from the National socioeconomics survey, a cross-sectional study conducted by the National Statistical Office (NSO) in 2010 and 2012. A total of 17,045 and 16,903 participants respectively who met the inclusion criteria were included in this study. The information was collected by face-to-face interview with structured questionnaires. Multilevel mixed-effects logistic regression analysis was performed to determine the potential socioeconomic factors associated with DM.

RESULTS

The prevalence of DM was 3.70% (95% CI: 3.36 to 4.05) and 8.11% (95%CI: 6.25 to 9.74) in 2010 and 2012 respectively and the prevalence of DM in 2012 was 1.36 times (95% CI: 1.25 to 1.48) when compared with 2010. The multilevel mixed-effects logistic regression observed that odds of having DM were significantly higher among those who aged 55-64 years old in 2010 and 65 years old or greater in 2012 (OR_adj = 18.13; 95%CI: 9.11 to 36.08, OR_adj 31.69; 95%CI: 20.78 to 48.33, respectively), females (OR_adj = 2.09; 95%CI: 1.66 to 2.62, OR_adj = 1.77; 95%CI: 1.54 to 2.05, respectively), and had lower education attainment (OR_adj = 5.87; 95%CI: 4.70 to 7.33, OR_adj= 1.22; 95%CI: 1.04 to 1.45, respectively) were also found to be associated with DM .

CONCLUSION

The study indicated that SES has been associated with DM. Those with female gender, old age and low educational attainment were vulnerable to DM.

Corrigendum to "Pancreatic Function, Type 2 Diabetes, and Metabolism in Aging"

[This corrects the article DOI: 10.1155/2012/320482.].

Type 2 Diabetes in the Elderly: Challenges in a Unique Patient Population

In the older patient population, rates of Type 2 Diabetes (T2D) and obesity are reaching epidemic proportions. In fact, older patients will soon constitute the majority of patients with T2D in most developed countries. The higher prevalence of T2D in older individuals is seen in both men and women and across racial and ethnic groups. However, certain ethnic groups are disproportionately affected and successful strategies must account for these fundamental differences. T2D in old age is associated with traditional diabetes-associated complications including micro- and macro vascular disease, but is also closely related to numerous other comorbidities including cognitive impairment, urinary incontinence, sarcopenia, and increased fall risk. An overall state of chronic inflammation and dysregulated immune system may underlie these increased risks; yet our understanding of immunometabolism during the aging process remains incomplete. In addition, optimal recognition and treatment of diabetes in the elderly is hampered by a lack of relevant, high-quality studies, as the majority of clinical trial data establishing risk profiles, glycemic targets, and therapeutic interventions for T2D are not applicable for large segments of the older patient population. Simply acknowledging this gap is inadequate. We need strong evidence-based data upon which to successfully identify diabetic patients and then intervene in ways that are targeted to specific individuals within a heterogeneous group of elderly patients with T2D.

Central Regulation of Glucose Production May Be Impaired in Type 2 Diabetes

The challenges of achieving optimal glycemic control in type 2 diabetes highlight the need for new therapies. Inappropriately elevated endogenous glucose production (EGP) is the main source of hyperglycemia in type 2 diabetes. Because activation of central ATP-sensitive potassium (KATP) channels suppresses EGP in nondiabetic rodents and humans, this study examined whether type 2 diabetic humans and rodents retain central regulation of EGP. The KATP channel activator diazoxide was administered in a randomized, placebo-controlled crossover design to eight type 2 diabetic subjects and seven age- and BMI-matched healthy control subjects. Comprehensive measures of glucose turnover and insulin sensitivity were performed during euglycemic pancreatic clamp studies following diazoxide and placebo administration. Complementary rodent clamp studies were performed in Zucker Diabetic Fatty rats. In type 2 diabetic subjects, extrapancreatic KATP channel activation with diazoxide under fixed hormonal conditions failed to suppress EGP, whereas matched control subjects demonstrated a 27% reduction in EGP (P = 0.002) with diazoxide. Diazoxide also failed to suppress EGP in diabetic rats. These results suggest that suppression of EGP by central KATP channel activation may be lost in type 2 diabetes. Restoration of central regulation of glucose metabolism could be a promising therapeutic target to reduce hyperglycemia in type 2 diabetes.

**-Postprandial pancreatic [11C]methionine uptake after pancreaticoduodenectomy mirrors basal beta cell function and insulin release

Purpose

[S-methyl-¹¹C]-L-methionine ([¹¹C]MET) uptake in the pancreas might be a central indicator of beta cell function. Since gastric emptying was recently shown to influence glycemic control in subjects after pancreaticoduodenectomy (PD, the surgical treatment of neoplasms of the pancreas head), we looked for imaginable relationships between gastric emptying, pre- and postprandial insulin concentrations, and [¹¹C]MET uptake.

Methods

Nineteen tumor-free survivors after PD (age mean ± SD: 61 ± 8.7 yrs.; 10 male, 9 female) and 10 healthy controls (age: 27 ± 8.7 yrs.; 7 male, 3 female) were given a mixed test meal. One gram of paracetamol was ingested with the meal to evaluate the speed of gastric emptying. Insulin, glucose, and paracetamol plasma concentrations were measured before and over 180 minutes after ingestion. Beta cell function was calculated from fasting glucose and insulin plasma concentrations. Simultaneously, 800 MBq of [¹¹C]MET were administered and the activity (maximum tissue standardized uptake values [SUVmax]) over the pancreas was measured at 15, 30, and 60 minutes after injection. Total integrated SUVmax (area under the curve [AUC]) and incremental SUVmax were calculated.

Results

The uptake of [¹¹C]MET in the pancreas was significantly higher (p < 0.0001) in controls compared to the PD group. Gastric emptying was significantly slower in controls compared to pancreatectomy subjects (p < 0.0001). Paracetamol AUC₃₀ correlated with the SUVmax increment between 15 and 30 minutes (R² = 0.27, p = 0.0263), suggesting a relationship between gastric emptying and the uptake of [¹¹C]MET. Total integrated SUVmax correlated with insulin AUC₆₀ (R² = 0.66,p < 0.0001) in patients after PD. Multivariate regression analysis revealed insulin AUC₆₀ and beta cell function, calculated from the fasting insulin to glucose ratio, as independent predictors of ¹¹C-methionine uptake, i.e. total integrated SUVmax, in patients after PD (R² = 0.78, p < 0.0001).

Conclusion

Postprandial [¹¹C]MET uptake may represent basal and postprandial beta cell function. The findings suggest a possible usefulness of this imaging procedure for further studying beta cell function.

Mechanism of Regulation of Adipocyte Numbers in Adult Organisms Through Differentiation and Apoptosis Homeostasis

Considering that adipose tissue (AT) is an endocrine organ, it can influence whole body metabolism. Excessive energy storage leads to the dysregulation of adipocytes, which in turn induces abnormal secretion of adipokines, triggering metabolic syndromes such as obesity, dyslipidemia, hyperglycemia, hyperinsulinemia, insulin resistance and type 2 diabetes. Therefore, investigating the molecular mechanisms behind adipocyte dysregulation could help to develop novel therapeutic strategies. Our protocol describes methods for evaluating the molecular mechanism affected by hypoxic conditions of the AT, which correlates with adipocyte apoptosis in adult mice. This protocol describes how to analyze AT in vivo through gene expression profiling as well as histological analysis of adipocyte differentiation, proliferation and apoptosis during hypoxia exposure, ascertained through staining of hypoxic cells or HIF-1α protein. Furthermore, in vitro analysis of adipocyte differentiation and its responses to various stimuli completes the characterization of the molecular pathways behind possible adipocyte dysfunction leading to metabolic syndromes.

Environmental Strategies to Promote Food Intake in Older Adults: A Narrative Review

Aging is often accompanied by lower intakes of food energy and consequent negative effects on health. To some extent this is due to declines in physiological ability, including the sensory responsiveness to regulate food intake. Fortunately, environmental factors may still influence food intake in older adults. Factors such as social facilitation, modeling, and nutrition knowledge and skills have been shown to stimulate their food intake. While environmental factors such as the eating location, portion size, food presentation, and labeling are known to influence eating behavior, their effectiveness in stimulating food intake in older persons is not well delineated. It is suggested that improving the environmental stimuli that promote food intake is a viable strategy to overcome age-related declines in nutrient intakes. This strategy is so promising that further research is warranted.

Glucagon secretion is increased in patients with Type 2 diabetic nephropathy

AIMS

Currently little is known about the relationship between renal function, albuminuria and glucagon; we analyzed the secretion of glucagon (GLA) and C-peptide in Type 2 diabetic patients with different degrees of nephropathy.

METHODS

357 patients with Type 2 diabetes including 119 cases without nephropathy and 238 cases with nephropathy were divided into four groups according to the stages of diabetic nephropathy. Patients with diabetic nephropathy were further classified according to the level of estimated glomerular filtration rate (eGFR). OGTT and insulin, C-peptide, glucagon releasing tests were performed in all patients. Characteristics of glucagon and C-peptide secretion in different groups were compared. Glucagon/glucose ratio (GLA/GLU) and glucagon/insulin ratio (GLA/INS) were used to represent the inhibition of glucose or insulin on glucagon secretion, respectively.

RESULTS

With the progress of diabetic nephropathy, glucagon level increased significantly; the glucagon peak after glucose load delayed from 60 min to 120 min, whereas C-peptide level decreased significantly. Related factors analysis suggested that glucagon was independently correlated with eGFR. Further analysis showed that glucagon level was higher in group with eGFR<60 ml/min compared with that in group with eGFR≥60 ml/min. In addition, both GLA/INS and GLA/GLU were higher in group with eGFR<60 ml/min compared with those in group with eGFR≥60 ml/min.

CONCLUSIONS

Patients with Type 2 diabetic nephropathy have worsened islet alpha and beta cell function. Therefore medications based on the regulation of glucagon secretion may improve glycemic control and also be beneficial for delaying the progress of diabetic nephropathy.

Role of microRNAs in the age-associated decline of pancreatic beta cell function in rat islets

AIMS/HYPOTHESIS

Ageing can lead to reduced insulin sensitivity and loss of pancreatic beta cell function, predisposing individuals to the development of diabetes. The aim of this study was to assess the contribution of microRNAs (miRNAs) to age-associated beta cell dysfunction.

METHODS

The global mRNA and miRNA profiles of 3- and 12-month-old rat islets were collected by microarray. The functional impact of age-associated differences in miRNA expression was investigated by mimicking the observed changes in primary beta cells from young animals.

RESULTS

Beta cells from 12-month-old rats retained normal insulin content and secretion, but failed to proliferate in response to mitotic stimuli. The islets of these animals displayed modifications at the level of several miRNAs, including upregulation of miR-34a, miR-124a and miR-383, and downregulation of miR-130b and miR-181a. Computational analysis of the transcriptomic modifications observed in the islets of 12-month-old rats revealed that the differentially expressed genes were enriched for miR-34a and miR-181a targets. Indeed, the induction of miR-34a and reduction of miR-181a in the islets of young animals mimicked the impaired beta cell proliferation observed in old animals. mRNA coding for alpha-type platelet-derived growth factor receptor, which is critical for compensatory beta cell mass expansion, is directly inhibited by miR34a and is likely to be at least partly responsible for the effects of this miRNA.

CONCLUSIONS/INTERPRETATION

Changes in the level of specific miRNAs that occur during ageing affect the proliferative capacity of beta cells. This might reduce their ability to expand under conditions of increased insulin demand, favouring the development of type 2 diabetes.

Diabetes and Its Effect on Bone and Fracture Healing

Diabetes mellitus is a metabolic disorder that increases fracture risk, interferes with bone formation, and impairs fracture healing. Type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) both increase fracture risk and have several common features that affect the bone including hyperglycemia and increased advanced glycation end product (AGE) formation, reactive oxygen species (ROS) generation, and inflammation. These factors affect both osteoblasts and osteoclasts leading to increased osteoclasts and reduced numbers of osteoblasts and bone formation. In addition to fracture healing, T1DM and T2DM impair bone formation under conditions of perturbation such as bacteria-induced periodontal bone loss by increasing osteoblast apoptosis and reducing expression of factors that stimulate osteoblasts such as BMPs and growth factors.

The emergence of sedentary behaviour physiology and its effects on the cardiometabolic profile in young and older adults

It has recently emerged that sedentary behaviour is independent of a lack of physical activity as individuals can be sufficiently active, based on the recommended physical activity guidelines, but also spend the majority of their waking hours engaging in sedentary behaviour. Individuals who follow this pattern of physical activity and sedentary behaviour are known as 'active couch potatoes'. Sedentary behaviour has been found to have detrimental effects on cardiometabolic markers associated with cardiovascular disease. Since the positive effects of moderate-to-vigorous intensity physical activity do not necessarily negate the deleterious effects of sedentary behaviour on cardiometabolic markers, it is postulated that engaging in light physical activity is an intervention that will successfully reduce levels of sedentary behaviour and may hence improve health markers of quality of life. We propose that such lifestyle changes may be particularly relevant to older populations as these engage in sedentary behaviour for the majority of their waking hours, thereby adding to the negative aging effect on cardiometabolic markers.

Effects of low-fat diet and aging on metabolic profiles of Creb3l4 knockout mice

BACKGROUND/OBJECTIVES

Increased adipose tissue mass closely associates with the development of insulin resistance and type 2 diabetes mellitus. Previously, we reported that CREB3L4 expressed in adipose tissue negatively regulates adipogenesis, and Creb3l4 knockout mice fed a high-fat diet for 16 weeks showed fat cell hyperplasia, with improved glucose tolerance and insulin sensitivity. These mice did not show significant weight gain and fat mass. Because fat diet or aging is known to be associated with the development of obesity, we examined the effects of Creb3l4 gene subjected to low-fat diet (LFD) or aging process on body composition and obesity risk.

SUBJECTS/METHODS

We fed Creb3l4 knockout mice a low-fat diet for 16 weeks (LFD group) or chow diet for over 1 year (aged group) and observed various metabolic parameters in the LFD-fed and aged Creb3l4 knockout mice.

RESULTS

LFD-fed and aged Creb3l4 knockout mice showed significant weight gain and adiposity, impaired glucose tolerance and decreased insulin sensitivity, compared with wild-type mice.

CONCLUSIONS

Creb3l4 has a critical role in metabolic phenotypes and a better understanding of its function may provide improved insight into the etiology of diabetes and other metabolic disorders.

Nutritional supplements in support of resistance exercise to counter age-related sarcopenia

Age-related sarcopenia, composed of myopenia (a decline in muscle mass) and dynapenia (a decline in muscle strength), can compromise physical function, increase risk of disability, and lower quality of life in older adults. There are no available pharmaceutical treatments for this condition, but evidence shows resistance training (RT) is a viable and relatively low-cost treatment with an exceptionally positive side effect profile. Further evidence suggests that RT-induced increases in muscle mass, strength, and function can be enhanced by certain foods, nutrients, or nutritional supplements. This brief review focuses on adjunctive nutritional strategies, which have a reasonable evidence base, to enhance RT-induced gains in outcomes relevant to sarcopenia and to reducing risk of functional declines.

Bisphenol-A treatment during pregnancy in mice: a new window of susceptibility for the development of diabetes in mothers later in life

Evidence now exists supporting the hypothesis that endocrine-disrupting chemicals (EDCs) can harmfully impact glucose metabolism. Thus, EDCs are beginning to be considered important contributors to the increased incidence of diabetes, obesity, or both. The possible effect of exposure to EDCs during pregnancy on glucose homeostasis in mothers later in life is presently unknown. Here we show that several months after delivery, mothers treated with the widespread EDC bisphenol-A (BPA) during gestation, at environmentally relevant doses, exhibit profound glucose intolerance and altered insulin sensitivity as well as increased body weight. These mice presented a decreased insulin secretion both in vivo and in vitro together with reduced pancreatic β-cell mass. The proliferation capacity was decreased in association with a diminished expression of the cell cycle activators: cyclin D2 and cyclin-dependent kinase-4. In addition, the rate of β-cells apoptosis was increased as well as the expression of the cell cycle inhibitors p16 and p53. Conversely, no effects on glucose metabolism or insulin sensitivity were observed when female nonpregnant mice were treated with BPA at the same doses. Taken together, these findings reveal that BPA exposure during gestation has harmful long-term implications in glucose metabolism for the mother. This finding highlights a new window of susceptibility for EDC exposure that may be important for the development of type 2 diabetes.

Defects in β-cell Ca2+ dynamics in age-induced diabetes

Little is known about the molecular mechanisms underlying age-dependent deterioration in β-cell function. We now demonstrate that age-dependent impairment in insulin release, and thereby glucose homeostasis, is associated with subtle changes in Ca(2+) dynamics in mouse β-cells. We show that these changes are likely to be accounted for by impaired mitochondrial function and to involve phospholipase C/inositol 1,4,5-trisphosphate-mediated Ca(2+) mobilization from intracellular stores as well as decreased β-cell Ca(2+) influx over the plasma membrane. We use three mouse models, namely, a premature aging phenotype, a mature aging phenotype, and an aging-resistant phenotype. Premature aging is studied in a genetically modified mouse model with an age-dependent accumulation of mitochondrial DNA mutations. Mature aging is studied in the C57BL/6 mouse, whereas the 129 mouse represents a model that is more resistant to age-induced deterioration. Our data suggest that aging is associated with a progressive decline in β-cell mitochondrial function that negatively impacts on the fine tuning of Ca(2+) dynamics. This is conceptually important since it emphasizes that even relatively modest changes in β-cell signal transduction over time lead to compromised insulin release and a diabetic phenotype.

Specific suppression of insulin sensitivity in growth hormone receptor gene-disrupted (GHR-KO) mice attenuates phenotypic features of slow aging

In addition to their extended lifespans, slow-aging growth hormone receptor/binding protein gene-disrupted (knockout) (GHR-KO) mice are hypoinsulinemic and highly sensitive to the action of insulin. It has been proposed that this insulin sensitivity is important for their longevity and increased healthspan. We tested whether this insulin sensitivity of the GHR-KO mouse is necessary for its retarded aging by abrogating that sensitivity with a transgenic alteration that improves development and secretory function of pancreatic β-cells by expressing Igf-1 under the rat insulin promoter 1 (RIP::IGF-1). The RIP::IGF-1 transgene increased circulating insulin content in GHR-KO mice, and thusly fully normalized their insulin sensitivity, without affecting the proliferation of any non-β-cell cell types. Multiple (nonsurvivorship) longevity-associated physiological and endocrinological characteristics of these mice (namely beneficial blood glucose regulatory control, altered metabolism, and preservation of memory capabilities) were partially or completely normalized, thus supporting the causal role of insulin sensitivity for the decelerated senescence of GHR-KO mice. We conclude that a delayed onset and/or decreased pace of aging can be hormonally regulated.

A combined analysis of 48 type 2 diabetes genetic risk variants shows no discriminative value to predict time to first prescription of a glucose lowering drug in Danish patients with screen detected type 2 diabetes

OBJECTIVE

To investigate the genetic influence of 48 type 2 diabetes susceptibility variants on disease progression measured as risk of early prescription redemption of glucose lowering drugs in screen-detected patients with type 2 diabetes.

METHODS

We studied type 2 diabetes progression in 1,480 patients with screen-detected type 2 diabetes from the ADDITION-Denmark study using information of redeemed prescriptions from the Register of Medicinal Products Statistics from 2001-2009 in Denmark. Patients were cluster randomized by general practitioners, who were randomized to treat type 2 diabetes according to either a conventional or a multifactorial intensive treatment algorithm. We investigated the genetic influence on diabetes progression by constructing a genetic risk score (GRS) of all 48 validated type 2 diabetes susceptibility variants, a GRS of 11 variants linked to β-cell function and a GRS of 3 variants linked to insulin sensitivity and assessed the association between number of risk alleles and time from diagnosis until first redeemed prescription of either any glucose lowering drug or an insulin drug.

RESULTS

The GRS linked to insulin sensitivity only nominally increased the risk of an early prescription redemption with an insulin drug by 39% (HR [95% C.I.] = 1.39 [1.09-1.77], p = 0.009] in patients randomized to the intensive treatment group. Furthermore, the strongest univariate predictors of diabetes progression for the intensive treatment group (measured as time to first insulin) were younger age (HR [95% C.I.] = 0.96 [0.93-0.99]), increased BMI (1.05 [1.01-1.09]), increased HbA1c (1.50 [1.36-.66]), increased TG (1.24 [1.11-1.39]) and reduced fasting serum HDL (0.37 [0.17-0.80]) at baseline. Similar results were obtained for the conventional treatment group.

CONCLUSION

Higher levels of HbA1c, fasting circulating levels of triglyceride, lower HDL, larger BMI and younger age are significant determinants of early pharmacological intervention in type 2 diabetes. However, known common type 2 diabetes-associated gene variants do not appear to significantly affect disease progression.

Biochemical alterations during the obese-aging process in female and male monosodium glutamate (MSG)-treated mice

Obesity, from children to the elderly, has increased in the world at an alarming rate over the past three decades, implying long-term detrimental consequences for individual’s health. Obesity and aging are known to be risk factors for metabolic disorder development, insulin resistance and inflammation, but their relationship is not fully understood. Prevention and appropriate therapies for metabolic disorders and physical disabilities in older adults have become a major public health challenge. Hence, the aim of this study was to evaluate inflammation markers, biochemical parameters and glucose homeostasis during the obese-aging process, to understand the relationship between obesity and health span during the lifetime. In order to do this, the monosodium glutamate (MSG) obesity mice model was used, and data were evaluated at 4, 8, 12, 16 and 20 months in both female and male mice. Our results showed that obesity was a major factor contributing to premature alterations in MSG-treated mice metabolism; however, at older ages, obesity effects were attenuated and MSG-mice became more similar to normal mice. At a younger age (four months old), the Lee index, triglycerides, total cholesterol, TNF-α and transaminases levels increased; while adiponectin decreased and glucose tolerance and insulin sensitivity levels were remarkably altered. However, from 16 months old-on, the Lee index and TNF-α levels diminished significantly, while adiponectin increased, and glucose and insulin homeostasis was recovered. In summary, MSG-treated obese mice showed metabolic changes and differential susceptibility by gender throughout life and during the aging process. Understanding metabolic differences between genders during the lifespan will allow the discovery of specific preventive treatment strategies for chronic diseases and functional decline.