Diabetes and obesity: therapeutic targeting and risk reduction - a complex interplay

The Role of Screening, Risk Factors, and Early Intervention in Preventing Diabetes in the Obese Population: A Systematic Review

With its rising global prevalence, diabetes has become one of the most significant and challenging health problems afflicting the world's population today. The increasing burden of diabetes and its associated complications calls for immediate action for prevention which primarily includes addressing the risk factors. The most significant risk factor for the onset of diabetes is obesity. Obesity and diabetes rates have been rising simultaneously, posing a threat to patient mortality and driving up community healthcare costs. A weight loss of five percent or more of total body weight has been shown to improve the quality of life, reduce the need for pharmacological therapy for diabetes, and enhance glycemic control. This level of weight loss can have significant health benefits, particularly for individuals with diabetes or at risk for developing diabetes. We aim to conduct this systematic review to assess diverse risk factors contributing to the incidence of diabetes among the obese population and determine various preventive strategies and recommendations in practice for the prevention of diabetes in this cohort. As a result, we included original studies that recruited the obese and diabetic populations and defined preventive measures for early intervention. Additionally, we included studies published in the last 10 years (2014-2024) only for the latest evidence. Studies including obese populations with cardiovascular diseases and neurological disorders were excluded. The Newcastle-Ottoman Castle assessment tool was utilized to assess the quality of the studies. We included nine studies that recruited 60,645 patients and were published between 2015 and 2022. Findings suggest that obesity alone is a significant contributor to the occurrence or onset of diabetes. At the same time, the presence of other risk factors, including hypertension, dyslipidemia, elevated triglycerides, or HDL and LDL levels, may further increase the risk of diabetes and its associated complications among the obese population. Preventive strategies emphasize early intervention through increasing awareness and educating communities about risk factors and lifestyle interventions, including the limitations of fast food diets for the prevention of diabetes and weight control. Since obesity is considered to be an independent risk factor for the development of diabetes, addressing and managing it is of critical importance clinically. Targeted early interventions, including screening for risk factors, health promotion, and education activities, can aid in the adaptation of healthier lifestyles, which can reduce the burden of these diseases significantly.

Levels of anti-insulin antibodies in diabetic retinopathy patients: an observational cross-sectional study

Aim: This study evaluated the levels of anti-insulin antibodies (AIAs) and the influence of some antidiabetic medications on AIA in diabetes mellitus (DM) patients with retinopathy. Patient & methods: An observational cross-sectional study. Results: A lower titer of AIA IgG was observed in the diabetic retinopathy (DR) and DM-only study categories compared with the control group [DR = 86 (5-560), DM-only = 50 (5-500), versus control = 200 (7-565); p = 0.017]. Taking nifedipine and metformin were negatively correlated (r = -0.32, p = 0.04) with the levels of AIA IgE in the DR group. Conclusion: A decreased titer of circulating AIAs was observed in the DR study category, suggesting that AIA may not contribute to the pathogenesis of DR.

Microbial-Based Bioactive Compounds to Alleviate Inflammation in Obesity

The increased prevalence of obesity with several other metabolic disorders, including diabetes and non-alcoholic fatty liver disease, has reached global pandemic proportions. Lifestyle changes may result in a persistent positive energy balance, hastening the onset of these age-related disorders and consequently leading to a diminished lifespan. Although suggestions have been raised on the possible link between obesity and the gut microbiota, progress has been hampered due to the extensive diversity and complexities of the gut microbiota. Being recognized as a potential biomarker owing to its pivotal role in metabolic activities, the dysregulation of the gut microbiota can give rise to a persistent low-grade inflammatory state associated with chronic diseases during aging. This chronic inflammatory state, also known as inflammaging, induced by the chronic activation of the innate immune system via the macrophage, is controlled by the gut microbiota, which links nutrition, metabolism, and the innate immune response. Here, we present the functional roles of prebiotics, probiotics, synbiotics, and postbiotics as bioactive compounds by underscoring their putative contributions to (1) the reduction in gut hyperpermeability due to lipopolysaccharide (LPS) inactivation, (2) increased intestinal barrier function as a consequence of the upregulation of tight junction proteins, and (3) inhibition of proinflammatory pathways, overall leading to the alleviation of chronic inflammation in the management of obesity.

A decreased level of high-density lipoprotein is a possible risk factor for type 2 diabetes mellitus: A review

Introduction

Type 2 diabetes mellitus (T2DM) is characterized primarily by dyslipidemia and hyperglycemia due to insulin resistance. High-density lipoprotein (HDL) play a significant role in preventing the incidence of dyslipidemia and its complications. HDL has different protective functions, such as reducing oxidation, vascular inflammation, and thrombosis; additionally, its anti-diabetic role is one of the most significant recent discoveries about HDL and some of its constituent lipoproteins.

Methods

This research reviews ongoing studies and preliminary investigations into the assessment of relation between decreased level of HDL and T2DM.

Results

The levels of HDL and its functions contribute to glucose hemostasis and the development of T2DM through four possible mechanisms, including insulin secretion by beta cells, peripheral insulin sensitivity, non-insulin-dependent glucose uptake, and adipose tissue metabolic activity. Additionally, the anti-oxidant properties of HDL protect beta cells from apoptosis caused by oxidative stress and inflammation induced by low-density lipoprotein, which facilitate insulin secretion.

Conclusion

Therefore, HDL and its compositions, especially Apo A-I, play an important role in regulating glucose metabolism, and decreased levels of HDL can be considered a risk factor for DM. Different factors, such as hypoalphalipoproteinemia that manifests as a consequence of genetic factors, such as Apo A-I deficiency, as well as secondary causes arising from lifestyle choices and underlying medical conditions that decrease the level of HDL, could be associated with DM. Moreover, intricate connections between HDL and diabetic complications extend beyond glucose metabolism to encompass complications like cardiovascular disease and kidney disease. Therefore, the exact interactions between HDL level and DM should be evaluated in future studies.

Obesogenic diet and metabolic syndrome among adolescents in India: data-driven cluster analysis

BACKGROUND

Metabolic syndrome is on the rise in India and is primarily linked to obesogenic dietary habits. The synergy of both is a prominent risk factor for cardiovascular diseases (CVDs). Hence, the present study aims to unveil clusters at high risk of metabolic syndrome and ascertain cluster characteristics based on dietary patterns among adolescents aged 10-19 years.

DATA AND METHODS

The study utilizes secondary data, i.e., Comprehensive National Nutrition Survey conducted in 2016-18. The study sample includes children and adolescents aged 10-19 years. An unsupervised learning algorithm was used to ascertain possible clusters in the data based on individuals' dietary patterns. The k-means were used to cluster the data according to their dietary patterns. To determine the number of clusters elbow method was used, and appropriate validation indices were also obtained for the final k. Further, to ascertain the distribution of the obesogenic dietary patterns and metabolic conditions in each cluster was analysed. Bivariate descriptive analysis was used to draw further inferences.

RESULTS

The k-means clusters identified five optimum clusters based on 12,318 adolescents (6333 males (mean age:14.2 ± 2.8) and 5985 females (mean age:14.3 ± 2.8)) 17 dietary patterns. Clusters were named based on how prudent these were in terms of consuming a healthy diet. Cluster phenotypic characteristics were defined as follows: a cluster of obesogenic diets (24%) constituted the highest proportion of the total sample and was significantly suffering from obesity (p < 0.001), and greater proportions of lipid anomalies (p = 0.51) and hypertension (p = 0.44) but not statistically significant. In contrast, 21% of the sample comprised a plant-based diet cluster and suffered from all deficiencies but folate (p = 0.625), zinc (p = 0.132), and greater proportion from obesity (p = 0.19; not significant), and diabetes (p < 0.001). A cluster of "convenient" (20%) mainly suffered from lipid anomalies (p = 0.00), diabetes (p = 0.03), and a greater proportion from hypertension (p = 0.56) with deficiencies of all the essential vitamins and minerals but significantly from vitamin A (p < 0.001), folate (p < 0.001), and iron (p = 0.017). Lastly, the cluster of those who follow a "Western diet" (17%) was found to have lipid anomalies (p = 0.003), diabetes (p = 0.016), greater proportion of vitamin B12 (p = 0.136), D (p = 0.002), folate (p < 0.001), and iron deficiencies (p = 0.013).

CONCLUSIONS AND RELEVANCE

Adolescents in India show a strong association between obesogenic diet and metabolic syndrome. Therefore, the burden of metabolic syndrome at early ages can be prevented by controlling obesogenic dietary practices and addressing micronutrient deficiencies. This may be done by targeted health promotional campaigns in schools and college-going populations in India.

Changes in body weight and cardiovascular risk factors in a Chinese population with type 2 diabetes mellitus: a longitudinal study

Introduction

The primary care management of blood glucose, blood pressure, lipid profiles, and body weight is important among patients with type 2 diabetes mellitus (T2DM) to prevent disease progression. Information on how weight changes would improve or deteriorate cardiovascular (CV) risk factors is warranted for making primary care recommendations. We aimed to investigate the changes in body weight and CV risk factors and to analyse their association in a Chinese population with T2DM.

Methods

We retrieved longitudinal data between 2020 and 2021 from 1,758 adult primary care patients enrolled in a diabetic retinopathy (DR) screening programme. Linear associations of changes in body weight with CV risk factors were explored. Multivariable logistic regression analysis was performed to examine associations between different weight change categories and the worsening of CV risk factors.

Results

The mean age of all the participants was 63.71 years, and over half of participants were females. During a one-year follow-up period, 24.7% of patients had a weight loss of ≥3%, while 22.2% of patients had a weight gain of ≥3%. Patients who had a weight loss of ≥3% were more likely to prevent the worsening of haemoglobin A1c (HbA1c) and triglycerides, while those who had a weight gain of ≥3% tended to have worsened HbA1c, lipid profiles, and blood pressure.

Conclusion

Results from this real-world investigation suggested the concurrent need for weight loss intervention among patients who are overweight or obese and weight gain prevention among patients whose body weight falls within the normal range in the context of community-based diabetes management.

Investigating the potential non-authorized use of two different formulations of liraglutide in Europe: A real-world drug utilization study

AIM

To assess the in-market use of Saxenda (liraglutide 3.0 mg) and Victoza (liraglutide 1.2 mg/1.8 mg) according to approved indications and posology.

MATERIALS AND METHODS

This retrospective, non-interventional study was conducted at 41 sites from December 2016 to May 2019. Via medical record review, physicians at each site identified patients who had been prescribed Saxenda (Italy) or Victoza (Italy/Germany) within the 24 months following launch in each country. Pseudonymized data were abstracted on patient and site characteristics, indication for the prescription, posology and duration of usage. Adherence to the approved indications and posology, and to the Saxenda stopping rule, were assessed. No formal statistical analysis was performed.

RESULTS

A total of 440 patients were prescreened and 225 (51.1%) were enrolled (Saxenda: N = 75, all in Italy; Victoza: N = 75 in Italy and N = 75 in Germany). In all, 96% (72/75) of Saxenda prescriptions, and 98.7% (148/150) of Victoza, were in accordance with the approved indications. Among the 40 patients treated with Saxenda for 16 weeks or longer, only two (5.0%) were confirmed as non-adherent to the stopping rule. Adherence could not be assessed in 23 (57.5%) patients because of missing body weight measurements.

CONCLUSIONS

This retrospective, real-world post-authorization safety study provides reassurance that Saxenda and Victoza are primarily used according to the approved European label, thus their real-world utilization did not raise safety concerns.

Twenty-four-hour movement guidelines during middle adolescence and their association with glucose outcomes and type 2 diabetes mellitus in adulthood

PURPOSE

The aim of the present study was to determine the association between adherence to the 24-h movement guidelines during middle adolescence and glucose outcomes (glycated hemoglobin and fasting glucose) and type 2 diabetes mellitus (T2DM) in adulthood, 14 and 22 years later.

METHODS

We analyzed data from apparently healthy adolescents aged 12-18 years who participated in Waves I and II (1994-1996, n = 14,738), Wave IV (2008-2009, n = 8913), and Wave V (2016-2018, n = 3457) of the National Longitudinal Study of Adolescent to Adult Health (Add Health) in the United States. Physical activity, screen time, and sleep duration were measured using questionnaires, and the 24-h guidelines were defined as: 5 or more times moderate-to-vigorous physical activity per week, ≤2 h per day of screen time, and 9-11 h of sleep for 12-13 years and 8-10 h for 14-17 years. Capillary and venous whole blood was collected and analyzed to determine glycated hemoglobin and fasting glucose for Waves IV and V, respectively.

RESULTS

Only 2.1% of the adolescents met all the 3 guidelines, and 37.8% met none of them. In both waves IV and V, adolescents who met physical activity and screen time guidelines had lower odds of T2DM in adulthood than those who did not meet any of these guidelines (Wave IV; prevalence ratio (PR) = 0.57, 95% confidence interval (95%CI): 0.21-0.89; Wave V: PR = 0.43, 95%CI: 0.32-0.74). Only for Wave V did adolescents who met all 3 guidelines have lower odds of T2DM at follow-up compared with those who did not meet any of these guidelines (PR = 0.47, 95%CI: 0.24-0.91). Also, for each increase in meeting one of the 24-h recommendations, the odds of T2DM decreased by 18% (PR = 0.82, 95%CI: 0.61-0.99) and 15% (PR = 0.85, 95%CI: 0.65-0.98) in adulthood for Waves IV and V, respectively.

CONCLUSION

Promoting all 24-h movement guidelines in adolescence, especially physical activity and screen time, is important for lowering the potential risk of T2DM in adulthood.

Association Between Chinese Visceral Adiposity Index and Incident Type 2 Diabetes Mellitus in Japanese Adults

BACKGROUND

Obesity is a well-known risk factor for type 2 diabetes mellitus (T2DM). Studies have shown that the Chinese visceral adiposity index (CVAI), a novel visceral adiposity indicator, is positive associated with the risk of T2DM in the Chinese population. This study aimed to investigate the correlation between CVAI and incident T2DM in a Japanese population.

METHODS

We performed a secondary analysis of open-access data from a retrospective cohort study. This study included 15,464 participants who received regular medical examinations at Murakami Memorial Hospital. All participants underwent a questionnaire survey, physical examination, and blood biochemical testing at baseline. The main outcome was new-onset T2DM during follow-up. Cox regression analysis and Kaplan-Meier analysis were used to analyze the risk of CVAI on T2DM, and we conducted smooth curve fitting. Receiver operating characteristic (ROC) curve analysis was performed to assess the predictive value of CVAI, body mass index (BMI), and waist circumference (WC) for incident T2DM.

RESULTS

During a median follow-up time of 5.39 years, 373 new-onset T2DM events were observed. Kaplan-Meier curves showed that the incidence of T2DM increased as the CVAI increased (log-rank χ ² = 187.1076 and 129.6067 in males and females, respectively, both P <0.001). After adjustment for covariates, per 1 increase of CVAI was associated with a 1.0133-fold and 1.0246-fold higher risk of incident T2DM in males and females, respectively (both P <0.001). Those individuals in the top CVAI quartile group had the highest risk of new-onset T2DM (HR = 3.1568 and 5.8415 in males and females, respectively, both P <0.05). A nonlinear relationship was identified by the smooth fitting curve between CVAI and T2DM events in both genders. ROC analysis indicated that CVAI had better predictive power than BMI and WC in both genders.

CONCLUSION

Our results demonstrate that CVAI was significantly associated with an increased risk of new-onset T2DM in Japanese adults.

Interaction of General or Central Obesity and Hypertension on Diabetes: Sex-Specific Differences in a Rural Population in Northeast China

PURPOSE

Some studies have established an association between hypertension or obesity and the risk of diabetes. This study aimed to examine the interaction of hypertension and obesity on diabetes.

PARTICIPANTS AND METHODS

The data of 11,731 Chinese men and women were analyzed from the 2012-2013 Northeast China Rural Cardiovascular Health Study. The interaction was examined by both additive and multiplicative scales. General obesity was measured by body mass index (BMI); central obesity was defined by waist circumference (WC), waist-to-height ratio (WHtR) and waist-to-hip ratio (WHpR).

RESULTS

After controlling for potential confounders, the odds ratios for diabetes were 3.864 (3.205-4.660), 4.500 (3.673-5.514), 4.932 (3.888-6.255) and 4.701 (3.817-5.788) for the combinations of hypertension and BMI, WC, WHtR or WHpR, respectively, which had the highest risk of diabetes among the four combinations. Notwithstanding the multiplicative interactions showed statistically significant in all analyses, the results of additive interactions were not consistent, suggesting the diabetes risk from female BMI (relative excess risk due to interaction (RERI): 1.136, 95% CI: 0.127-2.146, attributable proportion due to interaction (AP): 0.267, 95% CI: 0.057-0.477, synergy index (S):1.536, 95% CI: 1.017-2.321) or female WHpR (RERI: 1.076, 95% CI: 0.150-2.002, AP:0.205, 95% CI: 0.037-0.374, S:1.340, 95% CI: 1.012-1.775) was additive to the risk from hypertension.

CONCLUSION

The findings suggest that high BMI and high WHpR have synergistic interactions with hypertension on the risk of diabetes for females. The results of this study also suggest that BMI and WHpR, rather than WC, should be used for the diagnosis of metabolic syndrome in Chinese population.

The journey from white rice to ultra-high hydrostatic pressurized brown rice: an excellent endeavor for ideal nutrition from staple food

Although brown rice (BR) contains significantly higher levels of nutrients than the traditionally used polished white rice (WR), its consumption among the population is still not noteworthy. WR and BR are essentially same grain. The only difference between the two is the application of an exhaustive milling procedure during the processing of WR that removes all other layers of the grain except the portion of its white endosperm. BR, on the other hand, is prepared by removing only the outer hull of the rice seed. Thus, in addition to its inner endosperm, the bran and germ are also left on the BR. Hence, BR retains all its nutrients, including proteins, lipids, carbohydrates, fibers, vitamins, minerals, tocopherols, tocotrienols, γ-oryzanol, and γ-aminobutyric acid (GABA) packed into the bran and germ of the seed. Since BR tastes nutty and takes longer to cook than WR, it is not appreciated by the consumers. However, these problems have been circumvented using non-thermal ultra-high hydrostatic pressure (UHHP)-processing for the treatment of BR. A superior modification in the physicochemical and functional qualities of UHHPBR, along with its ability to curb human diseases may make it a more palatable and nutritious choice of rice over WR or the untreated-BR. Here, we have reviewed the mechanism by which UHHP treatment leads to the modification of nutrients such as proteins, lipids, carbohydrates, and fibers. We have focused on the effects of rice on cell and animal models of different conditions such as hyperlipidemia, diabetes, and hypertension and the possible mechanisms. Finally, we have emphasized the effects of UHHPBR in human cases with rare conditions such as osteoporosis and brain cognition - two age-related degenerative diseases of the elderly population.

The Effects of Resveratrol Supplementation on Endothelial Function and Blood Pressures Among Patients with Metabolic Syndrome and Related Disorders: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

INTRODUCTION

There are current trials investigating the effect of resveratrol supplementation on endothelial function and blood pressures among patients with metabolic syndrome (MetS); however, the findings are controversial.

AIM

This systematic review and meta-analysis of randomized controlled trials (RCTs) were carried out to summarize the effects of resveratrol supplementation on endothelial activation and blood pressures among patients with MetS and related disorders.

METHODS

We searched systematically online databases including: PubMed-Medline, Embase, ISI Web of Science and Cochrane Central Register of Controlled Trials until October, 2018. Two independent authors extracted data and assessed the quality of included articles. Data were pooled using the fixed- or random-effects model and considered as standardized mean difference (SMD) with 95% confidence intervals (95% CI).

RESULTS

Out of 831 electronic citations, 28 RCTs (with 33 findings reported) were included in the meta-analyses. The findings showed that resveratrol intervention significantly increased flow-mediated dilatation (FMD) levels (SMD 1.77; 95% CI 0.25, 3.29; P = 0.02; I2: 96.5). However, resveratrol supplements did not affect systolic blood pressure (SBP) (SMD - 0.27; 95% CI - 0.57, 0.03; P = 0.07; I2: 88.9) and diastolic blood pressure (DBP) (SMD - 0.21; 95% CI - 0.52, 0.11; P = 0.19; I2: 89.8).

CONCLUSIONS

Resveratrol supplementation significantly increased FMD among patients with MetS and related disorders, but did not affect SBP and DBP. Additional prospective studies are needed to investigate the effect of resveratrol supplementation on endothelial function and blood pressures, using higher-dose of resveratrol with longer durations.

An update on physical health and economic consequences of overweight and obesity

Overweight and obesity (OW and OB) have been on the increase globally and posed health risks to the world's population of all ages, including pre-born babies, children, adolescents, adults and elderly people, via their comorbid conditions. Excellent examples of comorbidities associated with obesity include cancer, cardiovascular diseases (CVD) and type 2 diabetes mellitus (T2DM). In this article, we aimed to review and update scientific evidence regarding the relationships between obesity and its common physical health consequences, including CVD, T2DM, hypertension, ischemic stroke, cancer, dyslipidemia and reproductive disorders. In addition, the economic burden of OW and OB will be discussed. Abundant evidence is found to support the associations between obesity and other diseases. In general, the odd ratios, risk ratios or hazard ratios are often higher in OW and OB people than in the normal-weight ones. However, the molecular mechanism of how OW and OB induce the development of other diseases has not been fully understood. Figures also showed that obesity and its-related disorders exert enormous pressure on the economy which is projected to increase. This review highlights the fact that obesity can lead to numerous lethal health problems; therefore, it requires a lot of economic resources to fight against this epidemic.

Overfed but undernourished: recognizing nutritional inadequacies/deficiencies in patients with overweight or obesity

Overweight and obesity are highly prevalent throughout the world and can adversely affect the nutritional status of individuals. Studies have shown that many people with obesity have inadequate intake of iron, calcium, magnesium, zinc, copper, folate and vitamins A and B₁₂, likely as a result of poor diet quality. Nutritional inadequacies or deficiencies may also occur due to altered pharmacokinetics in the individual with obesity and due to interactions in those with overweight or obesity with various pharmaceuticals. However, it has been demonstrated that the adult population in the United States as a whole is deficient in certain micronutrients as a result of the availability and overconsumption of high-calorie, low-nutrient processed foods. Poor nutrition may contribute to the development of certain chronic conditions, such as type 2 diabetes, which is already more prevalent in those with obesity. Clinicians need to be aware of these gaps, particularly in those individuals with obesity who are undergoing bariatric surgery or taking pharmaceutical products long term to facilitate weight loss. Patients with overweight or obesity likely struggle to achieve a balanced diet and may benefit from consultation with a dietitian. Along with providing recommendations for healthy eating and exercise, supplementation with specific micronutrients or multivitamins should be considered for individuals at the highest risk for or with established deficiencies. Further research is needed to understand the factors underlying nutritional inadequacies in individuals with overweight or obesity, as well as the outcomes of treatment strategies employed to address them.

Therapeutic Potential of Lentivirus-Mediated Glucagon-Like Peptide-1 Gene Therapy for Diabetes

Postprandial glucose-induced insulin secretion from the islets of Langerhans is facilitated by glucagon-like peptide-1 (GLP-1)-a metabolic hormone with insulinotropic properties. Among the variety of effects it mediates, GLP-1 induces delta cell secretion of somatostatin, inhibits alpha cell release of glucagon, reduces gastric emptying, and slows food intake. These events collectively contribute to weight loss over time. During type 2 diabetes (T2DM), however, the incretin response to glucose is reduced and accompanied by a moderate reduction in GLP-1 secretion. To compensate for the reduced incretin effect, a human immunodeficiency virus-based lentiviral vector was generated to deliver DNA encoding human GLP-1 (LentiGLP-1), and the anti-diabetic efficacy of LentiGLP-1 was tested in a high-fat diet/streptozotocin-induced model of T2DM. Therapeutic administration of LentiGLP-1 reduced blood glucose levels in obese diabetic Sprague Dawley rats, along with improving insulin sensitivity and glucose tolerance. Normoglycemia was correlated with increased blood GLP-1 and pancreatic beta cell regeneration in LentiGLP-1-treated rats. Plasma triglyceride levels were also normalized after LentiGLP-1 injection. Collectively, these data suggest the clinical potential of GLP-1 gene transfer therapy for the treatment of T2DM.

Regulation of adiposity by mTORC1

Obesity is characterized by an excessive increase in the adipose tissue mass, and is associated with higher incidence of several chronic metabolic diseases, such as type 2 diabetes. Therefore, its increasing prevalence is a public health concern, and it is important to better understand its etiology to develop new therapeutic strategies. Evidence accumulated over the years indicates that obesity is associated with a marked activation in adipose tissue of the mechanistic target of rapamycin complex 1 (mTORC1), a signaling pathway that controls lipid metabolism, and adipocyte formation and maintenance. Curiously, mTORC1 is also involved in the control of nonshivering thermogenesis and recruitment as well as browning of white adipose tissue. In this review, we explored mTORC1 functions in adipocytes and presented evidence, suggesting that mTORC1 may either increase or reduce adiposity, depending on the conditions and activation levels.

Knockdown of angiopoietin-like 2 mimics the benefits of intermittent fasting on insulin responsiveness and weight loss

Angiopoietin-like 2 (ANGPTL2) is an inflammatory adipokine linking obesity to insulin resistance. Intermittent fasting, on the other hand, is a lifestyle intervention able to prevent obesity and diabetes but difficult to implement and maintain. Our objectives were to characterize a link between ANGPTL2 and intermittent fasting and to investigate whether the knockdown of ANGPTL2 reproduces the benefits of intermittent fasting on weight gain and insulin responsiveness in knockdown and wild-type littermates mice. Intermittent fasting, access to food ad libitum once every other day, was initiated at the age of three months and maintained for four months. Intermittent fasting decreased by 63% (p < 0.05) gene expression of angptl2 in adipose tissue of wild-type mice. As expected, intermittent fasting improved insulin sensitivity (p < 0.05) and limited weight gain (p < 0.05) in wild-type mice. Knockdown mice fed ad libitum, however, were comparable to wild-type mice following the intermittent fasting regimen: insulin sensitivity and weight gain were identical, while intermittent fasting had no additional impact on these parameters in knockdown mice. Energy intake was similar between both wild-type fed intermittent fasting and ANGPTL2 knockdown mice fed ad libitum, suggesting that intermittent fasting and knockdown of ANGPTL2 equally lower feeding efficiency. These results suggest that the reduction of ANGPTL2 could be a useful and promising strategy to prevent obesity and insulin resistance, although further investigation of the mechanisms linking ANGPTL2 and intermittent fasting is warranted. Impact statement Intermittent fasting is an efficient diet pattern to prevent weight gain and improve insulin sensitivity. It is, however, a difficult regimen to follow and compliance is expected to be very low. In this work, we demonstrate that knockdown of ANGPTL2 in mice fed ad libitum mimics the beneficial effects of intermittent fasting on weight gain and insulin sensitivity in wild-type mice. ANGPTL2 is a cytokine positively associated with fat mass in humans, which inactivation in mice improves resistance to a high-fat metabolic challenge. This study provides a novel pathway by which IF acts to limit obesity despite equivalent energy intake. The development of a pharmacological ANGPTL2 antagonist could provide an efficient tool to reduce the burden of obesity.

Healthy lifestyle and normal waist circumference are associated with a lower 5-year risk of type 2 diabetes in middle-aged and elderly individuals: Results from the healthy aging longitudinal study in Taiwan (HALST)

Type 2 diabetes mellitus (DM) is known to be closely associated with lifestyle and obesity and has a prevalence that increases with age. This study aimed to assess the short-term composite effect of diet, physical activity, psychosocial health, and waist circumference (WC) on the incidence of DM in the elderly and to provide a lifestyle-based predictive index.We used baseline measurements (2009-2013) of 5349 community-dwelling participants (aged 55 years and older, 52% female) of the Healthy Aging Longitudinal Study in Taiwan (HALST) for fasting plasma glucose, HbA1C, serum cholesterol, triglycerides, blood pressures, WC, and outcomes of home-visit questionnaire. Principal component analysis (PCA) was used to identify participants with a healthy lifestyle (HLF: higher diet, physical activity, and psychosocial scores) and a lower WC, with cutoffs determined by the receiver-operating characteristics. A Cox regression model was applied to 3424 participants without DM at baseline by linking to their National Health Insurance records (median follow-up of 3.1 years).In total, 247 new DM cases (7.2%) were identified. The HLF and lower WC group had a relative risk (RR) of DM of 0.54 (95% CI 0.35-0.82) compared to the non-HLF and higher WC group. When stratified by the presence of impaired glucose tolerance (IGT) or metabolic syndrome (MS), only participants with IGT/MS showed significant risks (RR 0.55; 95% CI 0.33-0.92). However, except for WC, the individual lifestyle factors were nonsignificant in the overall model without PCA.A composite protective effect of HLF and normal WC on DM within 5 years was observed, especially in those with IGT or MS. Psychosocial health constituted an important lifestyle factor in the elderly. The cutoffs identified could be used as a lifestyle-based risk index for DM. Maintaining an HLF to prevent DM is especially important for the elderly.

Potential epigenetic biomarkers of obesity-related insulin resistance in human whole-blood

Obesity can increase the risk of complex metabolic diseases, including insulin resistance. Moreover, obesity can be caused by environmental and genetic factors. However, the epigenetic mechanisms of obesity are not well defined. Therefore, the identification of novel epigenetic biomarkers of obesity allows for a more complete understanding of the disease and its underlying insulin resistance. The aim of our study was to identify DNA methylation changes in whole-blood that were strongly associated with obesity and insulin resistance. Whole-blood was obtained from lean (n = 10; BMI = 23.6 ± 0.7 kg/m²) and obese (n = 10; BMI = 34.4 ± 1.3 kg/m²) participants in combination with euglycemic hyperinsulinemic clamps to assess insulin sensitivity. We performed reduced representation bisulfite sequencing on genomic DNA isolated from the blood. We identified 49 differentially methylated cytosines (DMCs; q < 0.05) that were altered in obese compared with lean participants. We identified 2 sites (Chr.21:46,957,981 and Chr.21:46,957,915) in the 5' untranslated region of solute carrier family 19 member 1 (SLC19A1) with decreased methylation in obese participants (lean 0.73 ± 0.11 vs. obese 0.09 ± 0.05; lean 0.68 ± 0.10 vs. obese 0.09 ± 0.05, respectively). These 2 DMCs identified by obesity were also significantly predicted by insulin sensitivity (r = 0.68, P = 0.003; r = 0.66; P = 0.004). In addition, we performed a differentially methylated region (DMR) analysis and demonstrated a decrease in methylation of Chr.21:46,957,915-46,958,001 in SLC19A1 of -34.9% (70.4% lean vs. 35.5% obese). The decrease in whole-blood SLC19A1 methylation in our obese participants was similar to the change observed in skeletal muscle (Chr.21:46,957,981, lean 0.70 ± 0.09 vs. obese 0.31 ± 0.11 and Chr.21:46,957,915, lean 0.72 ± 0.11 vs. obese 0.31 ± 0.13). Pyrosequencing analysis further demonstrated a decrease in methylation at Chr.21:46,957,915 in both whole-blood (lean 0.71 ± 0.10 vs. obese 0.18 ± 0.06) and skeletal muscle (lean 0.71 ± 0.10 vs. obese 0.30 ± 0.11). Our findings demonstrate a new potential epigenetic biomarker, SLC19A1, for obesity and its underlying insulin resistance.

Canagliflozin: Efficacy and Safety in Combination with Metformin Alone or with Other Antihyperglycemic Agents in Type 2 Diabetes

Metformin is typically the first pharmacologic treatment recommended for type 2 diabetes mellitus (T2DM), but many patients do not achieve glycemic control with metformin alone and eventually require combination therapy with other agents. Canagliflozin, a sodium glucose co-transporter 2 (SGLT2) inhibitor, was assessed in a comprehensive Phase 3 clinical development program consisting of ~10,000 participants, of which ~80% were on background therapy that consisted of metformin alone or in combination with other antihyperglycemic agents (AHAs; e.g., pioglitazone, sulfonylurea, and insulin). In addition, the efficacy and safety of canagliflozin and metformin as the initial combination therapy and canagliflozin monotherapy were assessed versus metformin in treatment-naïve patients with T2DM. Across studies in patients with T2DM who were on metformin alone or in combination with other AHAs, canagliflozin 100 and 300 mg provided improvements in glycated hemoglobin for up to 104 weeks. Canagliflozin was also associated with reductions in body weight and systolic blood pressure when added to background therapy consisting of metformin alone or with other AHAs. Canagliflozin was generally well tolerated, with increased incidence of adverse events (AEs) related to the mechanism of SGLT2 inhibition (i.e., genital mycotic infections, urinary tract infections, and osmotic diuresis-related AEs). Consistent with its insulin-independent mechanism of action, canagliflozin was associated with low rates of hypoglycemia when background therapy did not include sulfonylurea or insulin. Due to its favorable efficacy and safety profile, these results suggest that adding canagliflozin to a background regimen consisting of metformin or implementing treatment with a fixed-dose regimen of canagliflozin and metformin would provide an effective and safe treatment regimen for T2DM management.

FUNDING

Janssen Global Services, LLC.

Pre-germinated brown rice prevented high fat diet induced hyperlipidemia through ameliorating lipid synthesis and metabolism in C57BL/6J mice

Pre-germinated brown rice (PGBR) can ameliorate hyperlipidemia, but the action mechanism is not clear. We focus the mechanisms of PGBR prevented hyperlipidemia. Six-week-old mice were divided into: standard-regular diet (SRD), high-fat diet (HFD) and HFD with PGBR (HFD + PGBR) groups for 16 weeks. The HFD group has higher concentrations of TG, TC, HDL and Non-HDL in the blood, and a higher atherosclerosis index (AI). The TG levels in the liver, and TG, bile acid levels in the feces were enhanced; and the total adipocytokines level in adipose tissue was reduced. The HFD group had higher protein expressions of SREBP-1, SCD-1, FAS, LDLR, and CYP7α1 in the liver. Moreover, the greater expressions of SREBP-1, SCD-1, FAS and the less expressions of PPAR-α and adiponectin were in adipose tissue. In the HFD + PGBR group, the PGBR regulated the levels of TG, TC, HDL, Non-HDL, AI and adipocytokines. PGBR increased more cholesterol and bile acid exhaust in feces. The SREBP-1, SCD-1, FAS, HMGCR, LDLR, CYP7α1 and PPAR-α proteins in the liver; and the SREBP-1, SCD-1, FAS, PPAR-α and adiponectin proteins in adipose tissue were reversed by PGBR. Taken together, PGBR can improve lipid synthesis and metabolism, and we suggest PGBR is a recommendable food for controlling hyperlipidemia.

Puerarin Protects Pancreatic β-Cells in Obese Diabetic Mice via Activation of GLP-1R Signaling

Diabetes is characterized by a loss and dysfunction of the β-cell. Glucagon-like peptide 1 receptor (GLP-1R) signaling plays an important role in β-cell survival and function. It is meaningful to identify promising agents from natural products which might activate GLP-1R signaling. In this study, puerarin, a diet isoflavone, was evaluated its beneficial effects on β-cell survival and GLP-1R pathway. We showed that puerarin reduced the body weight gain, normalized blood glucose, and improved glucose tolerance in high-fat diet-induced and db/db diabetic mice. Most importantly, increased β-cell mass and β-cell proliferation but decreased β-cell apoptosis were observed in puerarin-treated diabetic mice as examined by immunostaining of mice pancreatic sections. The protective effect of puerarin on β-cell survival was confirmed in isolated mouse islets treated with high glucose. Further mechanism studies showed that the circulating level of GLP-1 in mice was unaffected by puerarin. However, puerarin enhanced GLP-1R signaling by up-regulating expressions of GLP-1R and pancreatic and duodenal homeobox 1, which subsequently led to protein kinase B (Akt) activation but forkhead box O1 inactivation, and promoted β-cell survival. The protective effect of puerarin was remarkably suppressed by Exendin(9-39), an antagonist of GLP-1R. Our study demonstrated puerarin improved glucose homeostasis in obese diabetic mice and identified a novel role of puerarin in protecting β-cell survival by mechanisms involving activation of GLP-1R signaling and downstream targets.

Paradox of using intensive lowering of blood glucose in diabetics and strategies to overcome it and decrease cardiovascular risks

Hyperglycemia significantly increases the risk of cardiovascular disease (CVD) in diabetics. However, it has been shown by a series of large scale international studies that intensive lowering of blood glucose levels not only has very limited benefits against cardiovascular problems in patients, but may even be harmful to patients at a high risk for CVD and/or poor long-term control of blood glucose levels. Therefore, Western medicine is faced with a paradox. One way to solve this may be administration of Chinese herbal medicines that not only regulate blood glucose, blood fat levels and blood pressure, but also act on multiple targets. These medicines can eliminate cytotoxicity of high glucose through anti-inflammatory and anti-oxidant methods, regulation of cytokines and multiple signaling molecules, and maintenance of cell vitality and the cell cycle, etc. This allows hyperglycemic conditions to exist in a healthy manner, which is called "harmless hyperglycemia" Furthermore, these cardiovascular benefits go beyond lowering blood glucose levels. The mechanisms of action not only avoid cardiovascular injury caused by intensive lowering of blood glucose levels, but also decrease the cardiovascular dangers posed by hyperglycemia.

Targeting FoxO1 with AS1842856 suppresses adipogenesis

Hyperplasia (i.e., increased adipogenesis) contributes to excess adiposity, the hallmark of obesity that can trigger metabolic complications. As FoxO1 has been implicated in adipogenic regulation, we investigated the kinetics of FoxO1 activation during adipocyte differentiation, and tested the effects of FoxO1 antagonist (AS1842856) on adipogenesis. We found for the first time that the kinetics of FoxO1 activation follows a series of sigmoid curves, and reveals the phases relevant to clonal expansion, cell cycle arrest, and the regulation of PPARγ, adiponectin, and mitochondrial proteins (complexes I and III). In addition, multiple activation-inactivation transitions exist in the stage of terminal differentiation. Importantly, persistent inhibition of FoxO1 with AS1842856 almost completely suppressed adipocyte differentiation, while selective inhibition in specific stages had differential effects on adipogenesis. Our data present a new view of FoxO1 in adipogenic regulation, and suggest AS1842856 can be an anti-obesity agent that warrants further investigation.

Shared decision making in type 2 diabetes with a support decision tool that takes into account clinical factors, the intensity of treatment and patient preferences: design of a cluster randomised (OPTIMAL) trial

BACKGROUND

No more than 10-15% of type 2 diabetes mellitus (T2DM) patients achieve all treatment goals regarding glycaemic control, lipids and blood pressure. Shared decision making (SDM) should increase that percentage; however, not all support decision tools are appropriate. Because the ADDITION-Europe study demonstrated two (almost) equally effective treatments but with slightly different intensities, it may be a good starting point to discuss with the patients their diabetes treatment, taking into account both the intensity of treatment, clinical factors and patients' preferences. We aim to evaluate whether such an approach increases the proportion of patients that achieve all three treatment goals.

METHODS

In a cluster-randomised trial including 40 general practices, that participated until 2009 in the ADDITION Study, 150 T2DM patients 60-80 years, known with T2DM for 8-15 years, will be included. Practices are randomised a second time, i.e. intervention practices in the ADDITION study could be control practices in the current study and vice versa. For the GPs from the intervention group a 2-hour training in SDM was developed as well as a decision support tool to be used during the consultation. GPs plan the first visit with the patients to decide on the intensity of the treatment, personalised targets and the priorities of treatment. The control group will continue with the treatment they were allocated to in the ADDITION study.

FOLLOW-UP

24 months. The primary outcome is the proportion of patients who achieve all three treatment goals. Secondary outcomes are the proportion of patients who achieve five treatment goals (HbA1c, blood pressure, total cholesterol, body weight, not smoking), evaluation of the SDM process (SDM-Q9 and CPS), satisfaction with the treatment (DTSQ), wellbeing and quality of life (W-BQ12, ADD QoL-19), health status (SF-36, EQ-5D) and coping (DCMQ). The proportions of achieved treatment goals will be compared between both groups. For the secondary outcomes mixed models will be used. The Medical Research Ethics Committee of the University Medical Centre Utrecht has approved the study protocol (Protocol number: 11-153).

DISCUSSION

This trial will provide evidence whether an intervention with a multi-faceted decision support tool increases the proportion of achieved personalised goals in type 2 diabetes patients.

TRIAL REGISTRATION

NCT02285881, November 4, 2014.

Tamoxifen reduces fat mass by boosting reactive oxygen species

As the pandemic of obesity is growing, a variety of animal models have been generated to study the mechanisms underlying the increased adiposity and development of metabolic disorders. Tamoxifen (Tam) is widely used to activate Cre recombinase that spatiotemporally controls target gene expression and regulates adiposity in laboratory animals. However, a critical question remains as to whether Tam itself affects adiposity and possibly confounds the functional study of target genes in adipose tissue. Here we administered Tam to Cre-absent forkhead box O1 (FoxO1) floxed mice (f-FoxO1) and insulin receptor substrate Irs1/Irs2 double floxed mice (df-Irs) and found that Tam induced approximately 30% reduction (P<0.05) in fat mass with insignificant change in body weight. Mechanistically, Tam promoted reactive oxygen species (ROS) production, apoptosis and autophagy, which was associated with downregulation of adipogenic regulator peroxisome proliferator-activated receptor gamma and dedifferentiation of mature adipocytes. However, normalization of ROS potently suppressed Tam-induced apoptosis, autophagy and adipocyte dedifferentiation, suggesting that ROS may account, at least in part, for the changes. Importantly, Tam-induced ROS production and fat mass reduction lasted for 4–5 weeks in the f-FoxO1 and df-Irs mice. Our data suggest that Tam reduces fat mass via boosting ROS, thus making a recovery period crucial for posttreatment study.

Determinants of glycaemic control in a practice setting: the role of weight loss and treatment adherence (The DELTA Study)

AIMS

Examine the association between weight loss and adherence with glycaemic goal attainment in patients with inadequately controlled T2DM.

MATERIALS AND METHODS

Patients ≥ 18 years with T2DM from a US integrated health system starting a new class of diabetes medication between 11/1/10 and 4/30/11 (index date) with baseline HbA1c ≥ 7.0% were included in this cohort study. Target HbA1c and weight change were defined at 6-months as HbA1c < 7.0% and ≥ 3% loss in body weight. Patient-reported medication adherence was assessed per the Medication Adherence Reporting Scale. Structural equation modelling was used to describe simultaneous associations between adherence, weight loss and HbA1c goal attainment.

RESULTS

Inclusion criteria were met by 477 patients; mean (SD) age 59.1 (11.6) years; 50.9% were female; 30.4% were treatment naïve; baseline HbA1c 8.6% (1.6); weight 102.0 kg (23.0). Most patients (67.9%) reported being adherent to the index diabetes medication. At 6 months mean weight change was -1.3 (5.1) kg (p = 0.39); 28.1% had weight loss of ≥ 3%. Mean HbA1c change was -1.2% (1.8) (p< 0.001); 42.8% attained HbA1c goal. Adherent patients (OR 1.70; p = 0.02) and diabetes therapies that lead to weight loss (metformin, GLP-1) were associated with weight loss ≥ 3% (OR 2.96; p< 0.001). Weight loss (OR 3.60; p < 0.001) and adherence (OR 1.59; p < 0.001) were associated with HbA1c goal attainment.

CONCLUSIONS

Weight loss ≥ 3% and medication adherence were associated with HbA1c goal attainment in T2DM; weight loss was a stronger predictor of goal attainment than medication adherence in this study population. It is important to consider weight-effect properties, in addition to patient-centric adherence counselling, when prescribing diabetes therapy.

Combating the dual burden: therapeutic targeting of common pathways in obesity and type 2 diabetes

The increasing prevalence of obesity is contributing substantially to the ongoing epidemic of type 2 diabetes. Abdominal adiposity, a feature of ectopic fat syndrome, is associated with silent inflammation, abnormal hormone secretion, and various metabolic disturbances that contribute to insulin resistance and insulin secretory defects, resulting in type 2 diabetes, and induce a toxic pattern that leads to cardiovascular disease, liver pathologies, and cancer. Despite the importance of weight control strategies in the prevention and management of type 2 diabetes, long-term results from lifestyle or drug interventions are generally disappointing. Furthermore, most of the classic glucose-lowering drugs have a side-effect of weight gain, which renders the management of most overweight or obese people with type 2 diabetes even more challenging. Many anti-obesity pharmacological drugs targeting central control of appetite were withdrawn from the market because of safety concerns. The gastrointestinal lipase inhibitor orlistat was the only anti-obesity drug available until the recent US, but not European, launch of phentermine-controlled-release topiramate and lorcaserin. Improved knowledge about bodyweight regulation opens new prospects for the potential use of peptides derived from the gut or the adipose tissue. Combination therapy will probably be necessary to avoid compensatory mechanisms and potentiate initial weight loss while avoiding weight regain. New glucose-lowering treatments, especially glucagon-like peptide-1 receptor agonists and sodium glucose cotransporter-2 inhibitors, offer advantages over traditional antidiabetic drugs by promoting weight loss while improving glucose control. In this Review, we explore the overlapping pathophysiology and also how various treatments can, alone or in combination, combat the dual burden of obesity and type 2 diabetes.

Evaluation of the relationship between weight change and glycemic control after initiation of antidiabetic therapy in patients with type 2 diabetes using electronic medical record data

AIMS

This study evaluates the relationship between HbA1c and weight change outcomes by anti-diabetic weight-effect properties in patients newly treated for type 2 diabetes; a relationship not previously characterized.

METHODS

Electronic medical records of patients with type 2 diabetes newly prescribed anti-diabetic monotherapy were assessed to identify HbA1c goal attainment [(<53 mmol/mol)] and weight change at 1-year. Anti-diabetics were categorized by weight-effect properties: weight-gain (sulfonylureas, thiazolidinediones) and weight-loss/neutral (metformin, DPP-4 inhibitors, GLP-1 agonists). Logistic regression analyses identified likelihood of attaining HbA1c goal or ≥3% weight loss by anti-diabetic category controlling for baseline characteristics. MANOVA was used to identify correlation between changes in weight and HbA1c.

RESULTS

The study included 28,290 patients. Mean age ± sd was 61 years ±11.8. Baseline HbA1c was 7.4% ± 1.6 (57 mmol/mol ± 17); 67.3% were prescribed a weight-loss/neutral anti-diabetic. At 1-year, more patients in the weight-loss/neutral anti-diabetic category lost weight (≥3%) than in the weight-gain anti-diabetic category (40.4% vs. 24.2%, p<0.001) or had an HbA1c<7.0% (<53 mmol/mol) (71.1% vs. 63.8%, p<0.001). Those prescribed a weight-gain anti-diabetic were 53% less likely to lose weight and 29% less likely to be at HbA1c goal than those prescribed a weight-loss/neutral anti-diabetic (p<0.001). Weight loss and HbA1c outcomes were significantly correlated (p<0.001).

CONCLUSIONS

Weight loss of ≥3% was associated with better glycemic control in patients newly treated for type 2 diabetes. Anti-diabetics associated with weight-loss/neutrality were associated with greater weight loss and HbA1c goal attainment and may facilitate efforts to co-manage weight and glycemia in the ambulatory-care setting.

Long-term testosterone therapy in hypogonadal men ameliorates elements of the metabolic syndrome: an observational, long-term registry study

AIM

The goal of this study was to determine if long-term testosterone (T) therapy in men with hypogonadism, henceforth referred to as testosterone deficiency (TD), ameliorates or improves metabolic syndrome (MetS) components.

METHODS

We performed a cumulative registry study of 255 men, aged between 33 and 69 years (mean 58.02 ± 6.30) with subnormal plasma total T levels (mean: 9.93 ± 1.38; range: 5.89-12.13 nmol/l) as well as at least mild symptoms of TD assessed by the Aging Males' symptoms scale. All men received treatment with parenteral T undecanoate 1000 mg (Nebido(®) , Bayer Pharma, Berlin, Germany), administered at baseline and 6 weeks and thereafter every 12 weeks for up to 60 months. Lipids, glucose, liver enzymes and haemoglobin A1c analyses were carried out in a commercial laboratory. Anthropometric measurements were also made throughout the study period.

RESULTS

Testosterone therapy restored physiological T levels and resulted in reductions in total cholesterol (TC) [7.29 ± 1.03 to 4.87 ± 0.29 mmol/l (281.58 ± 39.8 to 188.12 ± 11.31 mg/dl)], low-density lipoprotein cholesterol [4.24 ± 1.07 to 2.84 ± 0.92 mmol/l (163.79 ± 41.44 to 109.84 ± 35.41 mg/dl)], triglycerides [3.14 ± 0.58 to 2.16 ± 0.13 mmol/l (276.16 ± 51.32 to 189.78 ± 11.33 mg/dl)] and increased high-density lipoprotein levels [1.45 ± 0.46 to 1.52 ± 0.45 mmol/l (56.17 ± 17.79 to 58.85 ± 17.51 mg/dl)] (p < 0.0001 for all). There were marked reductions in systolic and diastolic blood pressure, blood glucose, haemoglobin A1c , C-reactive protein (6.29 ± 7.96 to 1.03 ± 1.87 U/l), alanine aminotransferase and aspartate aminotransferase (p < 0.0001 for all).

CONCLUSIONS

Long-term T therapy, at physiological levels, ameliorates MetS components. These findings strongly suggest that T therapy in hypogonadal men may prove useful in reducing the risk of cardiometabolic diseases.

Weight loss improves serum mediators and metabolic syndrome features in android obese subjects

Serum anti-/pro-inflammatory molecules such as adiponectin, IL-6, IL-10, and TNF-α, and metabolic syndrome (Met Syn) features in 15 android obese (6 Met Syn and 9 non-Met Syn) subjects were assessed during an 8-week weight control program. The results showed that the body mass index, weight, lean body mass, triglyceride, total cholesterol/high density lipoprotein cholesterol ratio, and TNF-α in Met Syn subjects were significantly (P < 0.05) improved. This study suggests that weight reduction in android obese subjects may be beneficial in reducing cardiovascular diseases via improving serum IL-6 and TNF-α levels, as well as Met Syn features.

Effects of naltrexone sustained-release/bupropion sustained-release combination therapy on body weight and glycemic parameters in overweight and obese patients with type 2 diabetes

OBJECTIVE

To assess the efficacy and safety of 32 mg naltrexone sustained-release (SR)/360 mg bupropion SR (NB) in overweight/obese individuals with type 2 diabetes with or without background oral antidiabetes drugs.

RESEARCH DESIGN AND METHODS

This was a 56-week, double-blind, placebo-controlled study in which 505 patients received standardized lifestyle intervention and were randomized 2:1 to NB or placebo. Coprimary end points were percent weight change and achievement of ≥5% weight loss. Secondary end points included achievement of HbA1c <7% (53 mmol/mol), achievement of weight loss ≥10%, and change in HbA1c, waist circumference, fasting blood glucose, and lipids.

RESULTS

In the modified intent-to-treat population (54% female, 80% Caucasian, and mean age 54 years, weight 106 kg, BMI 37 kg/m(2), and HbA1c 8.0% [64 mmol/mol]), NB resulted in significantly greater weight reduction (-5.0 vs. -1.8%; P < 0.001) and proportion of patients achieving ≥5% weight loss (44.5 vs. 18.9%, P < 0.001) compared with placebo. NB also resulted in significantly greater HbA1c reduction (-0.6 vs. -0.1% [6.6 vs. 1.1 mmol/mol]; P < 0.001), percent of patients achieving HbA1c <7% (53 mmol/mol) (44.1 vs. 26.3%; P < 0.001), and improvement in triglycerides and HDL cholesterol compared with placebo. NB was associated with higher incidence of nausea (42.3 vs. 7.1%), constipation (17.7 vs. 7.1%), and vomiting (18.3 vs. 3.6%). No difference was observed between groups in the incidence of depression, suicidal ideation, or hypoglycemia.

CONCLUSIONS

NB therapy in overweight/obese patients with type 2 diabetes induced weight loss, which was associated with improvements in glycemic control and select cardiovascular risk factors and was generally well tolerated with a safety profile similar to that in patients without diabetes.

Pectinase-Processed Ginseng Radix (GINST) Ameliorates Hyperglycemia and Hyperlipidemia in High Fat Diet-Fed ICR Mice

To develop a ginseng product possessing an efficacy for diabetes, ginseng radix ethanol extract was treated with pectinase and obtained the GINST. In the present study, we evaluate the beneficial effect of GINST on high fat diet (HFD)-induced hyper-glycemia and hyperlipidemia and action mechanism(s) in ICR mice. The mice were randomly divided into five groups: regular diet group (RD), high fat diet group (HFD), HFD plus GINST at 75 mg/kg (GINST75), 150 mg/kg (GINST150), and 300 mg/kg (GINST300). Oral glucose tolerance test reveals that GINST improves the glucose tolerance after glucose challenge. Fasting plasma glucose and insulin levels were decreased by 4.3% and 4.2% in GINST75, 10.9% and 20.0% in GINST150, and 19.6% and 20.9% in GINST300 compared to those in HFD control group. Insulin resistance indices were also markedly decreased by 8.2% in GINST75, 28.7% in GINST150, and 36.4% in GINST300, compared to the HFD control group. Plasma triglyceride, total cholesterol and non-esterified fatty acid levels in the GINST300 group were decreased by 13.5%, 22.7% and 24.1%, respectively, compared to those in HFD control group. Enlarged adipocytes of HFD control group were markedly decreased in GINST-treated groups, and shrunken islets of HFD control mice were brought back to near normal shape in GINST300 group. Furthermore, GINST enhanced phosphorylation of AMP-activated protein kinase (AMPK) and glucose transporter 4 (GLUT4). In summary, GINST prevents HFD-induced hyperglycemia and hyperlipidemia through reducing insulin resistance via activating AMPK-GLUT4 pathways, and could be a potential therapeutic agent for type 2 diabetes.

Cardiovascular effects of dipeptidyl peptidase-4 inhibitors: from risk factors to clinical outcomes

Dipeptidyl peptidase-4 (DPP-4) inhibitors (gliptins) are oral incretin-based glucose-lowering agents with proven efficacy and safety in the management of type 2 diabetes mellitus (T2DM). In addition, preclinical data and mechanistic studies suggest a possible additional non-glycemic beneficial action on blood vessels and the heart, via both glucagon-like peptide-1-dependent and glucagon-like peptide-1-independent effects. As a matter of fact, DPP-4 inhibitors improve several cardiovascular risk factors: they improve glucose control (mainly by reducing the risk of postprandial hyperglycemia) and are weight neutral; may lower blood pressure somewhat; improve postprandial (and even fasting) lipemia; reduce inflammatory markers; diminish oxidative stress; improve endothelial function; and reduce platelet aggregation in patients with T2DM. In addition, positive effects on the myocardium have been described in patients with ischemic heart disease. Results of post hoc analyses of phase 2/3 controlled trials suggest a possible cardioprotective effect with a trend (sometimes significant) toward lower incidence of major cardiovascular events with sitagliptin, vildagliptin, saxagliptin, linagliptin, or alogliptin compared with placebo or other active glucose-lowering agents. However, the definite relationship between DPP-4 inhibition and better cardiovascular outcomes remains to be proven. Major prospective clinical trials involving various DPP-4 inhibitors with predefined cardiovascular outcomes are under way in patients with T2DM and a high-risk cardiovascular profile: the Sitagliptin Cardiovascular Outcome Study (TECOS) on sitagliptin, the Saxagliptin Assessment of Vascular Outcomes Recorded in Patients With Diabetes Mellitus-Thrombolysis in Myocardial Infarction (SAVOR-TIMI) 53 trial on saxagliptin, the Cardiovascular Outcomes Study of Alogliptin in Subjects With Type 2 Diabetes and Acute Coronary Syndrome (EXAMINE) trial on alogliptin, and the Cardiovascular Outcome Study of Linagliptin Versus Glimepiride in Patients With Type 2 Diabetes (CAROLINA) on linagliptin. If these trials confirm that a DPP-4 inhibitor can reduce the cardiovascular burden of T2DM, it would be major progress that would dramatically influence the management of the disease.

PAS kinase as a nutrient sensor in neuroblastoma and hypothalamic cells required for the normal expression and activity of other cellular nutrient and energy sensors

PAS kinase (PASK) is a nutrient sensor that is highly conserved throughout evolution. PASK-deficient mice reveal a metabolic phenotype similar to that described in S6 kinase-1 S6K1-deficient mice that are protected against obesity. Hypothalamic metabolic sensors, such as AMP-activated protein kinase (AMPK) and the mammalian target of rapamycin (mTOR), play an important role in feeding behavior, the homeostasis of body weight, and energy balance. These sensors respond to changes in nutrient levels in the hypothalamic areas involved in feeding behavior and in neuroblastoma N2A cells, and we have recently reported that those effects are modulated by the anorexigenic peptide glucagon-like peptide-1 (GLP-1). Here, we identified PASK in both N2A cells and rat VMH and LH areas and found that its expression is regulated by glucose and GLP-1. High levels of glucose decreased Pask gene expression. Furthermore, PASK-silenced N2A cells record an impaired response by the AMPK and mTOR/S6K1 pathways to changes in glucose levels. Likewise, GLP-1 effect on the activity of AMPK, S6K1, and other intermediaries of both pathways and the regulatory role at the level of gene expression were also blocked in PASK-silenced cells. The absence of response to low glucose concentrations in PASK-silenced cells correlates with increased ATP content, low expression of mRNA coding for AMPK upstream kinase LKB1, and enhanced activation of S6K1. Our findings indicate that, at least in N2A cells, PASK is a key kinase in GLP-1 actions and exerts a coordinated response with the other metabolic sensors, suggesting that PASK might play an important role in feeding behavior.

Acute central neuropeptide Y administration increases food intake but does not affect hepatic very low-density lipoprotein (VLDL) production in mice

OBJECTIVE

Central neuropeptide Y (NPY) administration stimulates food intake in rodents. In addition, acute modulation of central NPY signaling increases hepatic production of very low-density lipoprotein (VLDL)-triglyceride (TG) in rats. As hypertriglyceridemia is an important risk factor for atherosclerosis, for which well-established mouse models are available, we set out to validate the effect of NPY on hepatic VLDL-TG production in mice, to ultimately investigate whether NPY, by increasing VLDL production, contributes to the development of atherosclerosis.

RESEARCH DESIGN AND METHODS

Male C57Bl/6J mice received an intracerebroventricular (i.c.v.) cannula into the lateral (LV) or third (3V) ventricle of the brain. One week later, after a 4 h fast, the animals received an intravenous (i.v.) injection of Tran(35)S (100 µCi) followed by tyloxapol (500 mg/kg body weight; BW), enabling the study of hepatic VLDL-apoB and VLDL-TG production, respectively. Immediately after the i.v. injection of tyloxapol, the animals received either an i.c.v. injection of NPY (0.2 mg/kg BW in artificial cerebrospinal fluid; aCSF), synthetic Y1 receptor antagonist GR231118 (0.5 mg/kg BW in aCSF) or vehicle (aCSF), or an i.v. injection of PYY3-36 (0.5 mg/kg BW in PBS) or vehicle (PBS).

RESULTS

Administration of NPY into both the LV and 3V increased food intake within one hour after injection (+164%, p<0.001 and +367%, p<0.001, respectively). NPY administration neither in the LV nor in the 3V affected hepatic VLDL-TG or VLDL-apoB production. Likewise, antagonizing central NPY signaling by either PYY3-36 or GR231118 administration did not affect hepatic VLDL production.

CONCLUSION

In mice, as opposed to rats, acute central administration of NPY increases food intake without affecting hepatic VLDL production. These results are of great significance when extrapolating findings on the central regulation of hepatic VLDL production between species.

Role of fat body lipogenesis in protection against the effects of caloric overload in Drosophila

The Drosophila fat body is a liver- and adipose-like tissue that stores fat and serves as a detoxifying and immune responsive organ. We have previously shown that a high sugar diet leads to elevated hemolymph glucose and systemic insulin resistance in developing larvae and adults. Here, we used stable isotope tracer feeding to demonstrate that rearing larvae on high sugar diets impaired the synthesis of esterified fatty acids from dietary glucose. Fat body lipid profiling revealed changes in both carbon chain length and degree of unsaturation of fatty acid substituents, particularly in stored triglycerides. We tested the role of the fat body in larval tolerance of caloric excess. Our experiments demonstrated that lipogenesis was necessary for animals to tolerate high sugar feeding as tissue-specific loss of orthologs of carbohydrate response element-binding protein or stearoyl-CoA desaturase 1 resulted in lethality on high sugar diets. By contrast, increasing the fat content of the fat body by knockdown of king-tubby was associated with reduced hyperglycemia and improved growth and tolerance of high sugar diets. Our work supports a critical role for the fat body and the Drosophila carbohydrate response element-binding protein ortholog in metabolic homeostasis in Drosophila.

Cardiovascular effects of gliptins

Dipeptidyl peptidase 4 (DPP-4) inhibitors (commonly referred to as gliptins) are a novel class of oral antihyperglycaemic agents with demonstrated efficacy in the treatment of type 2 diabetes mellitus (T2DM). Preclinical data and mechanistic studies have indicated a possible beneficial action on blood vessels and the heart, via both glucagon-like peptide 1 (GLP-1)-dependent and GLP-1-independent effects. DPP-4 inhibition increases the concentration of many peptides with potential vasoactive and cardioprotective effects. Clinically, DPP-4 inhibitors improve several risk factors in patients with T2DM. They improve blood glucose control (mainly by reducing postprandial glycaemia), are weight neutral (or even induce modest weight loss), lower blood pressure, improve postprandial lipaemia, reduce inflammatory markers, diminish oxidative stress, and improve endothelial function. Some positive effects on the heart have also been described in patients with ischaemic heart disease or congestive heart failure, although their clinical relevance requires further investigation. Post-hoc analyses of phase II-III, controlled trials suggest a possible cardioprotective effect with a trend for a lower incidence of major cardiovascular events with gliptins than with placebo or active agents. However, the actual relationship between DPP-4 inhibition and cardiovascular outcomes remains to be proven. Major prospective clinical trials with predefined cardiovascular outcomes and involving various DPP-4 inhibitors are now underway in patients with T2DM and a high-risk cardiovascular profile.

Weight change with liraglutide and comparator therapies: an analysis of seven phase 3 trials from the liraglutide diabetes development programme

AIM

We investigated the relationship between weight change and related factors in subjects with type 2 diabetes mellitus (T2DM) treated with liraglutide versus comparator diabetes therapies.

METHODS

Twenty-six-week data from seven phase 3, randomized trials in the liraglutide T2DM development programme were analysed by trial and treatment group: liraglutide (1.2 and 1.8 mg), active comparator and placebo. Outcome measures included proportions of subjects in various weight change categories and their percentage weight change from baseline; impact of body mass index (BMI) and gastrointestinal (GI) adverse events (AEs) on weight change and correlation of weight change with change in glycosylated haemoglobin (HbA1c).

RESULTS

A number of subjects experienced >5% weight loss during the trials (24.4% liraglutide 1.8 mg and 17.7% liraglutide 1.2 mg; 17.7% exenatide, 10.0% sitagliptin, 3.6-7.0% sulphonylurea, 2.6% thiazolidinedione and 2.6% glargine; 9.9% placebo). More weight loss was seen with liraglutide 1.2 and 1.8 mg than with active comparators except exenatide. Across trials, higher initial BMI was associated with slightly greater weight loss with liraglutide. Mean weight loss increased slightly the longer GI AEs persisted. Although HbA1c reduction was slightly larger in higher weight loss categories across treatments (including placebo), sample sizes were small and no clear correlation could be determined. Liraglutide-treated subjects experienced additional HbA1c reduction beyond that which appeared weight induced; thus, not all HbA1c-lowering effect appears weight mediated.

CONCLUSIONS

The majority of liraglutide-treated T2DM subjects experienced weight loss in this analysis. Weight loss was greater and occurred more in glucagon-like peptide-1 receptor agonist-treated subjects than in active comparator-treated subjects.

Therapeutic potential of VIP vs PACAP in diabetes

Type 2 diabetes (T2D) is characterized by chronic insulin resistance and a progressive decline in beta-cell function. Although rigorous glucose control can reduce morbidity and mortality associated with diabetes, achieving optimal long-term glycemic control remains to be accomplished in many diabetic patients. As beta-cell mass and function inevitably decline in T2D, exogenous insulin administration is almost unavoidable as a final outcome despite the use of oral antihyperglycemic agents in many diabetic patients. Pancreatic islet cell death, but not the defect in new islet formation or beta-cell replication, has been blamed for the decrease in beta-cell mass observed in T2D patients. Thus, therapeutic approaches designed to protect islet cells from apoptosis could significantly improve the management of T2D, because of its potential to reverse diabetes not just ameliorate glycemia. Therefore, an ideal beta-cell-preserving agent is expected to protect beta cells from apoptosis and stimulate postprandial insulin secretion along with increasing beta-cell replication and/or islet neogenesis. One such potential agent, the islet endocrine neuropeptide vasoactive intestinal peptide (VIP) strongly stimulates postprandial insulin secretion. Because of its broad spectrum of biological functions such as acting as a potent anti-inflammatory factor through suppression of Th1 immune response, and induction of immune tolerance via regulatory T cells, VIP has emerged as a promising therapeutic agent for the treatment of many autoimmune diseases including diabetes.

The effect of sitagliptin versus glibenclamide on arterial stiffness, blood pressure, lipids, and inflammation in type 2 diabetes mellitus patients

AIM

This study evaluated the effect of sitagliptin versus glibenclamide on arterial stiffness, blood pressure, lipid profile, oxidative stress, and high-sensitivity C-reactive protein (hsCRP) in type 2 diabetes mellitus patients.

SUBJECTS AND METHODS

Forty diabetes patients, inadequately controlled on metformin, were randomly assigned to either sitagliptin (100 mg/day) or glibenclamide (5 mg/day) for 3 months. Following a 1-month washout period, a crossover switch from glibenclamide to sitagliptin and vice versa was performed for an additional 3 months. Arterial stiffness, 24-h ambulatory blood pressure monitoring, lipids, hsCRP, glycated hemoglobin, fasting glucose, STAT-8-isoprostane (a measure of oxidative stress), body mass index (BMI), and waist circumference were measured at baseline and at 3 months with each of the study drugs.

RESULTS

Thirty-four patients completed the study. Glibenclamide had a better glucose-lowering effect than sitagliptin, but this was associated with more hypoglycemic events. BMI increased following glibenclamide treatment, whereas sitagliptin proved weight-neutral. Mean BMI gain was +0.5±1.0 kg/m(2) for glibenclamide versus -0.01±0.9 kg/m(2) for sitagliptin (P<0.001). Triglyceride levels significantly dropped following sitagliptin, although they remained unaltered after glibenclamide treatment. Mean triglyceride decrease was -18.4±45 mg/mL after sitagliptin but -0.2±57 mg/dL following glibenclamide treatment (P=0.018). There was no change in low-density lipoprotein, high-density lipoprotein, arterial stiffness, blood pressure monitoring, hsCRP, or STAT-8-isoprostane with each of the study drugs.

CONCLUSIONS

Sitagliptin, but not glibenclamide, demonstrated a significant beneficial effect on BMI and triglyceride levels. However, arterial stiffness, blood pressure, oxidative stress, and inflammatory status were not significantly affected by adding sitagliptin or glibenclamide to metformin-treated type 2 diabetes patients.