Update on the treatment of type 2 diabetes mellitus

Pure additive contribution of genetic variants to a risk prediction model using propensity score matching: application to type 2 diabetes

The achievements of genome-wide association studies have suggested ways to predict diseases, such as type 2 diabetes (T2D), using single-nucleotide polymorphisms (SNPs). Most T2D risk prediction models have used SNPs in combination with demographic variables. However, it is difficult to evaluate the pure additive contribution of genetic variants to classically used demographic models. Since prediction models include some heritable traits, such as body mass index, the contribution of SNPs using unmatched case-control samples may be underestimated. In this article, we propose a method that uses propensity score matching to avoid underestimation by matching case and control samples, thereby determining the pure additive contribution of SNPs. To illustrate the proposed propensity score matching method, we used SNP data from the Korea Association Resources project and reported SNPs from the genome-wide association study catalog. We selected various SNP sets via stepwise logistic regression (SLR), least absolute shrinkage and selection operator (LASSO), and the elastic-net (EN) algorithm. Using these SNP sets, we made predictions using SLR, LASSO, and EN as logistic regression modeling techniques. The accuracy of the predictions was compared in terms of area under the receiver operating characteristic curve (AUC). The contribution of SNPs to T2D was evaluated by the difference in the AUC between models using only demographic variables and models that included the SNPs. The largest difference among our models showed that the AUC of the model using genetic variants with demographic variables could be 0.107 higher than that of the corresponding model using only demographic variables.

Inhibition of JAK-STAT and NF-κB signalling systems could be a novel therapeutic target against insulin resistance and type 2 diabetes

AIMS

Chronic inflammation is associated with the production of high levels of proinflammatory cytokines via the JAK-STAT and NF-κB signalling pathways which are known to be inhibited by tofacitinib and aspirin respectively. High levels of these cytokines increase the synthesis of suppressors of cytokines (SOCS), which at high levels inhibit insulin signalling leading to insulin resistance. The effects of tofacitinib and aspirin on the degree of insulin resistance in type 2 diabetic rats were determined.

MATERIALS AND METHODS

Rats were induced with type 2 diabetes (T2D) by administration of 10% fructose solution (ad libitum) followed by streptozotocin injection (40 mg/kg BW) and treated with different doses of tofacitinib (10 and 20 mg/kg BW), aspirin (100 and 200 mg/kg BW) and combination of the two drugs at both doses for 9 weeks.

KEY FINDINGS

Results showed that separate treatment with 10 mg/kg BW tofacitinib and 100 mg/kg BW aspirin significantly (P < 0.05) decreased tumour necrosis factor-α (TNF-α), interleukin 6 (IL-6) and serum amyloid A when compared to diabetic untreated rats. However, the combined therapy (10 mg/kg BW tofacitinib and 100 mg/kg BW aspirin) significantly decreased the levels of TNF-α, IL-6, serum amyloid A, HOMA-IR, blood glucose level and SOC-3 gene expression but significantly (P < 0.05) improved glucose homoestasis, insulin secretion, HOMA-β and GLUT-4 gene expression when compared to diabetic untreated rat.

CONCLUSION

It was concluded that simultaneous inhibition of the JAK-STAT and NF-κB signalling pathways with tofacitinib and aspirin respectively, could mitigate insulin resistance and hyperglycemia in T2D.

Synergistic effect of novel chitosan combined metformin drug on streptozotocin-induced diabetes mellitus rat

Metformin is widely used as a frontline medicine of type-II diabetes. Frequent overdose side-effects and their consequent adversative need to be reduced. The novel source of marine hydrozoa, Thyroscyphus ramosus derived chitosan combined metformin drug was administrated to evaluate the antidiabetic potential on a high-fat diet (HFD) with streptozotocin (STZ) induced diabetic rats. The primary analysis of In vitro antioxidant activity was tested for various solvent dissolved chitosan. Based on their IC₅₀ dose values, CsnAA was chosen for further experiments. The chitosan was combined with metformin by sonication and confirmed through XRD, FTIR and SEM analysis. The enhanced activity was observed in 100 mg/kg metformin combined with CSN500mg/kg. The level of serum bilirubin, total protein, SGH, liver glycogen, Glucose-6-phosphatase and fructose-1,6- phosphatase values were significantly similar to metformin 300 mg/kg treated group. With this beneficiary, the novel chitosan was recommended to administrate with metformin to improve the drug efficacy and reduction of overdose lethal effects.

Functional Cereal Products in the Diet for Type 2 Diabetes Patients

Type 2 diabetes has become one of the major health problems of the modern world. It is assumed that environmental factors have a significant impact on the development of the disease, and great importance is ascribed to the diet, which can be modified accordingly. The diet can exert prophylactic and therapeutic effects; changes in the diet in advanced disease can improve the quality of life of diabetic patients and minimise the risk of complications, which are the direct cause of diabetes-related death. Functional food, which has a potentially health-enhancing effect in addition to its nutritional value, has been increasingly recognised and required. Cereal products are crucial in diabetic nutrition. Their function can additionally be enhanced by fortification with compounds with proven hypoglycaemic effects. Pasta has a low glycaemic index and is a good carrier of fortifying substances; hence, it can be highly recommended in diets for diabetic patients.

Pharmacists' Attitudes and Role in Diabetes Management in Bosnia and Herzegovina

INTRODUCTION

Diabetes is the fastest growing chronic diseases worldwide and in Bosnia and Herzegovina. International standards for diabetes care have recognized the crucial role of pharmacists in diabetes management. Community pharmacists can provide services beyond medication dispensing inducing patient identification, assessment, education, referral, monitoring and behavioral counseling. Pharmacists' attitudes toward diabetes are generally positive but do not correlate with the degree of their involvement in diabetes management and frequency of providing diabetes-related services varied throughout countries.

AIM

To measure pharmacists' attitude toward diabetes management and to identify pharmacy services that are currently provided to patients with diabetes.

MATERIAL AND METHODS

We have conducted a descriptive, cross-sectional survey-based study among pharmacists from Bosnia and Herzegovina attending on of the conferences in May 2018. Majority of pharmacist attending such conferences are from community pharmacies across the whole country considering surveyed sample was representative. The questionnaire contained 3 different sections: a) participants' demographics, b) measured participants' attitude toward diabetes using the DAS-3 to measure participants' degree of agreement to 33 diabetes-related statements, on a 5-point Likert type scale and c) a list of possible diabetes patient support activities that could be delivered by pharmacists based on authors experience and available literature.

RESULTS

The majority of respondents (86,5%) were female and 53,8% work in private owned pharmacies. Interest in diabetes was indicated by 94,2% while 59,6% completed special diabetes continuing education in the past. All the respondents expressed positive attitudes in all DAS-3 with no significant difference between overall DAS-3 and subscale values. Provided services differ but mainly drug oriented and partially include comorbidity counseling.

CONCLUSION

Pharmacists had positive attitudes toward diabetes but they provided limited diabetes-related services to patients. Additional special education is needed.

Open-Label Study to Assess the Efficacy of Ipragliflozin for Reducing Insulin Dose in Patients with Type 2 Diabetes Mellitus Receiving Insulin Therapy

Background and Objective

To avoid insulin-induced hypoglycemia and weight gain, the minimum dose of insulin should be used. In this study, therefore, we examined insulin dose reduction by ipragliflozin add-on therapy in Japanese patients with type 2 diabetes mellitus treated with long-acting basal insulin.

Methods

In this multicenter, open-label study, patients received one ipragliflozin 50-mg tablet once daily in combination with basal insulin for 24 weeks. The primary efficacy endpoint was the change and percent change in insulin dose from baseline to Week 24. Secondary efficacy endpoints included changes in glycated hemoglobin (HbA1c), fasting plasma glucose (FPG), glycoalbumin, cholesterol, leptin, adiponectin, C-peptide, glucagon, body weight, and blood pressure, and number of patients achieving withdrawal of insulin at the end of treatment (EOT). Treatment-emergent adverse events (TEAEs) were evaluated for safety.

Results

In total, 114 patients were screened, 103 were registered, and 97 completed the study. The mean age was 59 years and 72.8% of patients were male. The mean change in insulin dose from baseline at Week 24 was − 6.6 ± 4.4 units/day (p < 0.001); the mean percent change was − 29.87%. HbA1c, FPG, glycoalbumin, glucagon levels, body weight, and blood pressure significantly decreased from baseline to EOT (p < 0.05). Cholesterol, leptin, and adiponectin were unaffected. One patient was able to stop insulin treatment at Week 16. The incidence of TEAEs was 60.2%. Hypoglycemia (10.7%) and pollakiuria (13.6%) were the most common drug-related TEAEs. Conclusions Once-daily 50-mg ipragliflozin enabled a 30% dose reduction of insulin by Week 24 compared with baseline. No major safety concerns were raised.

Clinical Trial Registration

ClinicalTrials.gov (NCT02847091)

Electronic supplementary material

The online version of this article (10.1007/s40261-019-00851-z) contains supplementary material, which is available to authorized users.

Alpha-Glucosidase and Alpha-Amylase Inhibitory Activities of Novel Abietane Diterpenes from Salvia africana-lutea

The re-investigation of a methanolic extract of Salvia africana-lutea collected from the Cape Floristic Region, South Africa (SA), afforded four new abietane diterpenes, namely 19-acetoxy-12-methoxycarnosic acid (1), 3β-acetoxy-7α-methoxyrosmanol (2), 19-acetoxy-7α-methoxyrosmanol (3), 19-acetoxy-12-methoxy carnosol (4), and two known named clinopodiolides A (5), and B (6), in addition to four known triterpenes, oleanolic, and ursolic acids (7, 8), 11,12-dehydroursolic acid lactone (9) and β-amyrin (10). The chemical structural elucidation of the isolated compounds was determined on the basis of one and two dimensional nuclear magnetic resonance (1D and 2D NMR), high-resolution mass spectrometry (HRMS), ultra violet (UV), fourier transform infrared (IR), in comparison with literature data. The in vitro bio-evaluation against alpha-glucosidase showed strong inhibitory activities of 8, 10, and 7, with the half inhibitory concentration (IC50) values of 11.3 ± 1.0, 17.1 ± 1.0 and 22.9 ± 2.0 µg/mL, respectively, while 7 demonstrated the strongest in vitro alpha-amylase inhibitory activity among the tested compounds with IC50 of 12.5 ± 0.7 µg/mL. Additionally, some of the compounds showed significant antioxidant capacities. In conclusion, the methanolic extract of S. africana-lutea is a rich source of terpenoids, especially abietane diterpenes, with strong antioxidant and anti-diabetic activities that can be helpful to modulate the redox status of the body and could therefore be an excellent candidate for the prevention of the development of diabetes, a disease where oxidase stress plays an important role.

Effectiveness in clinical practice versus efficacy of dipeptidyl peptidase-4 inhibitors in clinical trials for type 2 diabetes: protocol for systematic review

INTRODUCTION

Data supporting the use of oral antidiabetic drugs mainly rely on data from premarketing clinical trials. Real-world data studies are crucial to evaluate effectiveness of drugs. The aim of this systematic review is to compare the results obtained for efficacy and effectiveness endpoints on clinical trials and those obtained from routine clinical practice of dipeptidyl peptidase-4 inhibitors.

METHODS AND ANALYSIS

This systematic review will include randomised controlled trials and observational studies evaluating the efficacy and effectiveness of dipeptidyl peptidase-4 inhibitors, respectively. A literature search will be performed at Medline, Embase, Cochrane Controlled Register of Trials and ClinicalTrials.gov. Search terms comprised the drug name (including the pharmacotherapeutic class and the international non-proprietary name). Data on haemoglobin A1C, blood glucose and body weight will be retrieved. The risk of bias will be independently assessed according to the checklist proposed by Downs and Black. Data will be analysed using descriptive statistics and meta-analysis when applicable.

ETHICS AND DISSEMINATION

Ethical approval is not required as no primary data are collected. This systematic review will be disseminated through a peer-reviewed publication and at conference meetings.

Effect of sitagliptin on tubulointerstitial Wnt/β-catenin signalling in diabetic nephropathy

AIM

To investigate the effect of sitagliptin on Wnt/β-catenin signalling in the tubulointerstitium of diabetic nephropathy.

METHODS

Forty male Wistar rats were divided into normal control (NC), diabetic model (DM), low and high-dose sitagliptin intervention groups (ST1 and ST2, respectively). Changes in the biochemical parameters and tubulointerstitial fibrosis index were observed. The levels of protein and gene expression of different indicators were detected via immunohistochemistry and real-time polymerase chain reaction. NRK-52E cells were divided into the normal control group, mannitol control group, high glucose group (HG), high glucose plus sitagliptin intervention group (HG + ST) and high glucose plus Wnt/β-catenin inhibitor group (HG + XAV939). The relevant indicators were examined by Western blot or enzyme-linked immunosorbent assay.

RESULTS

Compared with the NC group, the blood glucose, glycosylated haemoglobin, 24 h urinary albumin, creatinine clearance and tubulointerstitial fibrosis index were significantly increased in the DM group. These parameters were decreased in the ST1 and ST2 groups compared to the DM group. Compared with the NC group, the levels of Wnt4, β-catenin, dipeptidyl peptidase-4 and α-smooth muscle actin were higher and E-cadherin was lower in the DM group. Sitagliptin treatment reversed these changes. In the high glucose-stimulated NRK-52E cells, sitagliptin and XAV939 inhibited the elevated expression of Wnt4, β-catenin, dipeptidyl peptidase-4, α-smooth muscle actin, transforming growth factor-β and fibronectin and restored E-cadherin activity.

CONCLUSION

Sitagliptin may inhibit the tubulointerstitial Wnt/β-catenin signalling pathway in diabetic nephropathy and provide renal protection by alleviatinge renal tubulointerstitial transdifferentiation and fibrosis.

Fucoxanthin-Rich Brown Algae Extract Improves Male Reproductive Function on Streptozotocin-Nicotinamide-Induced Diabetic Rat Model

Hypogonadism and oxidative stress are occurring commonly in men with diabetes and associated male infertility. This study aimed to investigate the capability of anti-oxidative and anti-inflammatory properties of fucoxanthin as well as to evaluate its protective effects on male reproduction in diabetic rats. The RAW 264.7 macrophage cells were used to evaluate the anti-oxidative and anti-inflammatory activity. Thirty male Sprague-Dawley rats were induced by streptozotocin-nicotinamide for a diabetes model and fed either with three different doses of fucoxanthin (13, 26, and 65 mg/kg) or rosiglitazone (0.571 mg/kg) for four weeks. The fucoxanthin significantly inhibited nitric oxide production and reduced reactive oxygen species level in lipopolysaccharide-induced RAW 264.7 cells. In the animal study, fucoxanthin administration improved insulin resistance, restored sperm motility, decreased abnormal sperm number, and inhibited lipid peroxidation. Moreover, it restored GPR54 and SOCS-3 mRNA expression in the hypothalamus and recovered luteinizing hormone level, as well as the testosterone level. In conclusion, fucoxanthin not only possessed antioxidant and anti-inflammatory properties but also decreased the diabetes signs and symptoms as well as improved spermatogenesis and male reproductive function.

MiR-26a and miR-26b downregulate the expression of sucrase-isomaltase enzyme: A new chapter in diabetes treatment

Type II diabetes is a metabolic disease that has affected 460 million people around the globe and become a heavy burden on health care system. Diabetic patients suffer from hyperglycemia and hyperinsulinemia which can damage vital organs in body like heart, kidneys, eyes and nervous system. Different strategies have been introduced to control or lessen these diabetic complications in which one of the most promising approaches is the inhibition of intestinal sucrase-isomaltase (SI). Inhibition of this enzyme will block the release of glucose into bloodstream and lead to reduced postprandial hyperglycemia. MicroRNAs are small regulatory molecules that play critical roles in different cellular pathways and molecular mechanisms. It is proved that microRNAs have significant effects on cellular mechanisms involved in diabetes and can be used as biomarkers for diagnosis of this metabolic disease. Based on bioinformatics analysis miR-26a and miR-26b can interact with a conserved 3'-UTR region of SI mRNA which lead to a hypothesis that these miRs may have negative regulatory effect on this enzyme. In this study, we investigated the impact of high glucose conditions on expression of sucrase-isomaltase, miR-26a and miR-26b in caco-2 cell line. It is proved that in a simulated diabetic condition there is a reverse correlation between the expression pattern of these miRs and SI. QRT-PCR method was used to evaluate the expression of our target molecules. Interestingly, transfection of miR-26a and miR-26b in caco-2 cell line reduced the transcription of SI mRNA and decreased the sucrase and maltase activity of its active sites. To sum up, our results demonstrate the first evidence of the significant effect of miR-26a and miR-26b on SI expression and activity. We proved that these microRNAs may directly inhibit this enzyme and can be used as a new scaffold in search of finding novel treatments for type II diabetes.

CXCL13/CXCR5 signaling contributes to diabetes-induced tactile allodynia via activating pERK, pSTAT3, pAKT pathways and pro-inflammatory cytokines production in the spinal cord of male mice

Painful diabetic neuropathy (PDN) is a severely debilitating chronic pain syndrome. Spinal chemokine CXCL13 and its receptor CXCR5 were recently demonstrated to play a pivotal role in the pathogenesis of chronic pain induced by peripheral tissue inflammation or nerve injury. In this study we investigated whether CXCL13/CXCR5 mediates PDN and the underlying spinal mechanisms. We used the db/db type 2 diabetes mice, which showed obvious hyperglycemia and obese, long-term mechanical allodynia, and increased expression of CXCL13, CXCR5 as well as pro-inflammatory cytokines TNF-α and IL-6 in the spinal cord. Furthermore, in the spinal cord of db/db mice there is significantly increased gliosis and upregulated phosphorylation of cell signaling kinases, including pERK, pAKT and pSTAT3. Mechanical allodynia and upregulated pERK, pAKT and pSTAT3 as well as production of TNF-α and IL-6 were all attenuated by the noncompetitive NMDA receptor antagonist MK-801. If spinal giving U0126 (a selective MEK inhibitor) or AG490 (a Janus kinase (JAK)-STAT inhibitor) to db/db mice, both of them can decrease the mechanical allodynia, but only inhibit pERK (by U0126) or pSTAT3 (by AG490) respectively. Acute administration of CXCL13 in C57BL/6J mice resulted in exacerbated thermal hyperalgesia and mechanical allodynia, activation of the pERK, pAKT and pSTAT3 pathways and increased production of pro-inflammatory cytokines (IL-1β, TNF-α and IL-6), which were all attenuated by knocking out of Cxcr5. In all, our work showed that chemokine CXCL13 and its receptor CXCR5 in spinal cord contribute to the pathogenesis of PDN and may help develop potential novel therapeutic approaches for patients afflicted with PDN.

Targeting GPCRs Activated by Fatty Acid-Derived Lipids in Type 2 Diabetes

G protein-coupled receptors (GPCRs) are the most intensively studied drug targets, because of their diversity, cell-specific expression, and druggable sites accessible at the cell surface. Preclinical and clinical studies suggest that targeting GPCRs activated by fatty acid-derived lipids may have potential to improve glucose homeostasis and reduce complications in patients with type 2 diabetes (T2D). Despite the discontinued development of fasiglifam (TAK-875), the first FFA1 agonist to reach late-stage clinical trials, lipid-sensing receptors remain a viable target, albeit with a need for further characterization of their binding mode, intracellular signaling, and toxicity. Herein, we analyze general discovery trends, various signaling pathways, as well as possible challenges following activation of GPCRs that have been validated clinically to control blood glucose levels.

Type 2 diabetes and depression in the African American population

BACKGROUND AND PURPOSE

Type 2 diabetes mellitus (T2DM) affects 30.3 million people (9.4%) in the United States. African Americans are twice as likely to be diagnosed with diabetes and have two to four times the rates of T2DM-associated complications. Depression has long been associated with poor outcomes of diabetic self-management and glycemic control. Comorbidity of T2DM and depression worsen effective self-management of these conditions in the African American population. The purpose of the study was to synthesize the literature with practice recommendations of care related to T2DM and depression in the African American population.

METHODS

A literature search was conducted using PRISMA in June 2018 with PubMed, Google Scholar, Cochrane, Scopus, Embase, and PsycINFO databases using the years from 2008 through 2018. The following terms and combination of terms were used to identify articles for the review: (a) diabetes mellitus, type 2, (b) diabetes type 2 and depression, and (c) diabetes mellitus type 2, depression, African America.

CONCLUSIONS

The overall prevalence of depression with T2DM in African Americans is about 25%. The quality of care received by African Americans is lower when compared with non-Hispanic Whites, resulting in more emergency department visits and fewer physician visits per year. African Americans require supportive and trusting collaboration with providers for the ongoing optimal management of these complex conditions.

IMPLICATION FOR PRACTICE

Culturally relevant education on lifestyle modification may help mitigate barriers to management of T2DM and depression in the African American population. Using the diabetes self-management education/support to help empower African Americans may be essential for effective self-management strategies of T2DM and depression.

Natural Hydrogen Sulfide Donors from Allium sp. as a Nutraceutical Approach in Type 2 Diabetes Prevention and Therapy

Type 2 diabetes mellitus (DM) is a socially relevant chronic disease with high prevalence worldwide. DM may lead to several vascular, macrovascular, and microvascular complications (cerebrovascular, coronary artery, and peripheral arterial diseases, retinopathy, neuropathy, and nephropathy), often accelerating the progression of atherosclerosis. Dietary therapy is generally considered to be the first step in the treatment of diabetic patients. Among the current therapeutic options, such as insulin therapy and hypoglycemic drugs, in recent years, attention has been shifting to the effects and properties-that are still not completely known-of medicinal plants as valid and inexpensive therapeutic supports with limited side effects. In this review, we report the relevant effects of medicinal plants and nutraceuticals in diabetes. In particular, we paid attention to the organosulfur compounds (OSCs) present in plant extracts that due to their antioxidant, hypoglycemic, anti-inflammatory, and immunomodulatory effects, can contribute as cardioprotective agents in type 2 DM. OSCs derived from garlic (Allium sp.), due to their properties, can represent a valuable support to the diet in type 2 DM, as outlined in this manuscript based on both in vitro and in vivo studies. Moreover, a relevant characteristic of garlic OSCs is their ability to produce the gasotransmitter H₂S, and many of their effects can be explained by this property. Indeed, in recent years, several studies have demonstrated the relevant effects of endogenous and exogenous H₂S in human DM, including by in vitro and in vivo experiments and clinical trials; therefore, here, we summarize the effects and the underlying molecular mechanisms of H₂S and natural H₂S donors.

Anti-atherosclerotic effects between a combined treatment with simvastatin plus hirudin and single simvastatin therapy in patients with early type 2 diabetes mellitus

Background

This study aimed to investigate the efficacy and safety of simvastatin plus hirudin in preventing atherosclerosis in the patients with early type 2 diabetes mellitus (T2DM).

Methods

This was a 24-week, randomized, open-label and controlled study in which 150 outpatients initially diagnosed with T2DM were randomly assigned into either simvastatin (40 mg daily at night) plus hirudin (3 g thrice daily) group [combined group (CG) n=75] or simvastatin (40 mg once daily) group [monotherapy group (MG) n=75]. The therapeutic efficacy was evaluated by the score of carotid artery atherosclerosis, plaque size, peak systolic velocity (PSV) and end-diastolic velocity (EDV) on carotid ultrasonography at three and six months after treatment. Logistic regression analysis was used to investigate the correlation between treatment and carotid atherosclerosis.

Results

One hundred and thirty-one patients completed this study, and there were no significant differences in the dropout rate in the CG (14.67%) and the MG (10.67%). Significant difference was found in the incidence of adverse events in the CG compared with the MG (37.50% vs. 17.91%, P<0.05) due to the higher risk of hemorrhage (12.50% vs. 1.49%, P<0.05), which did not affect the treatment compliance. The efficacy of combined treatment was better than monotherapy in the enhancement of carotid artery atherosclerosis scores (P<0.01), the plaque thickness (P<0.05) and the change of PSV (P<0.05) and EDV (P<0.05) since three months after treatment, which maintained to the end of observation. In addition, hirudin treatment was able to independently predict the carotid artery atherosclerosis scores (β=2.37, P<0.05), the plaque thickening (β=3.51, P<0.01) and the change of PSV (β=1.69, P<0.05) and EDV (β=1.79, P<0.05).

Conclusions

Combined use of simvastatin and hirudin is well tolerated and possesses better anti-atherosclerotic effects than simvastatin alone in patients with early T2DM.

Possible molecular mechanisms of glucose-lowering activities of Momordica charantia (karela) in diabetes

Diabetes mellitus is a highly prevalent metabolic disorder which is characterized by impaired glucose tolerance, with a relative or absolute insulin deficiency and profound changes in the metabolism of macronutrients. Traditional and complementary medicine is therapeutic strategies that have both been applied to improving glycemic control. Momordica charantia is one of the plant-based, folk medicines that used for improving glycemic control. We aimed to review, the effects of M. charantia on blood glucose with a clarification of the molecular pathways involved. Of the compounds derived from the plants, the insulin-like peptide, charantin, and the alkaloid vicine, have been reported to have hypoglycemic effects. Different mechanisms contribute to the antidiabetic activities of M. charantia, these include increasing pancreatic insulin secretion, decreasing insulin resistance and increasing peripheral and skeletal muscle cell glucose utilization, inhibition of intestinal glucose absorption and suppressing of key enzymes in the gluconeogenic pathways.

Significance of Microalbuminuria in Predicting Silent Myocardial Ischemia in Patients with Type 2 Diabetes Using Myocardial Perfusion Imaging

OBJECTIVES

In light of increased risk of cardiovascular events and the poor prognosis of coronary artery disease (CAD) in diabetic versus non-diabetic patients and also with respect to the importance of early diagnosis of CAD in this status, the study was aimed to assess the importance of microalbuminuria in predicting silent myocardial ischemia (SMI) in patients with type 2 diabetes using myocardial perfusion imaging (MPI).

METHODS

This study included 120 patients with diabetes type 2, but without previously known CAD or any cardiac symptoms that were stratified into two groups based on presence/absence of microalbuminuria. All participants underwent CAD evaluation using gated myocardial perfusion single-photon emission computed tomography (MPS) imaging. Other clinical and laboratory indices were also recorded

RESULTS

Studied population consisted of 84 males (70%) and 36 females (30%), totally 120 patients with mean age of 58.61±9.90). In total, asymptomatic ischemia was detected in 78 (65%) of the included diabetic patients. Stress induced ischemia was found in 56 patients (87.5%) of albumin+ (Alb) group and in 22 patients (39.3%) of Alb- group. The frequency of stress induced ischemia was 10.81 times higher in the patients with microalbuminuria compared to Alb- ones [p<0.001, Odds ratio: 10.81, 95% confidence interval: 4.33-26.99]. On the other hand, no relationship was found between the presence of stress induced ischemia and therapy type, diabetes duration, history of evident retinopathy, history of hypertension and also serum levels of hemoglobin A1c (p>0.05).

CONCLUSION

The current study showed that abnormal MPI findings are significantly more common in diabetic patients with microalbuminuria. With respect to low cost and availability of urine Alb detection tests, it might be as a biomarker for prediction of SMI in daibetic population.

Cross-population analysis for functional characterization of type II diabetes variants

BACKGROUND

As Genome-Wide Association Studies (GWAS) have been increasingly used with data from various populations, it has been observed that data from different populations reveal different sets of Single Nucleotide Polymorphisms (SNPs) that are associated with the same disease. Using Type II Diabetes (T2D) as a test case, we develop measures and methods to characterize the functional overlap of SNPs associated with the same disease across populations.

RESULTS

We introduce the notion of an Overlap Matrix as a general means of characterizing the functional overlap between different SNP sets at different genomic and functional granularities. Using SNP-to-gene mapping, functional annotation databases, and functional association networks, we assess the degree of functional overlap across nine populations from Asian and European ethnic origins. We further assess the generalizability of the method by applying it to a dataset for another complex disease - Prostate Cancer. Our results show that more overlap is captured as more functional data is incorporated as we go through the pipeline, starting from SNPs and ending at network overlap analyses. We hypothesize that these observed differences in the functional mechanisms of T2D across populations can also explain the common use of different prescription drugs in different populations. We show that this hypothesis is concordant with the literature on the functional mechanisms of prescription drugs.

CONCLUSION

Our results show that although the etiology of a complex disease can be associated with distinct processes that are affected in different populations, network-based annotations can capture more functional overlap across populations. These results support the notion that it can be useful to take ethnicity into account in making personalized treatment decisions for complex diseases.

Metabolomics and Cell Therapy in Diabetes Mellitus

Diabetes with a broad spectrum of complications has become a global epidemic metabolic disorder. Till now, several pharmaceutical and non-pharmaceutical therapeutic approaches were applied for its treatment. Cell-based therapies have become promising methods for diabetes treatment. Better understanding of diabetes pathogenesis and identification of its specific biomarkers along with evaluation of different treatments efficacy, can be possible by clarification of specific metabolic modifications during the diabetes progression. Subsequently, metabolomics technology can support this goal as an effective tool. The present review tried to show how metabolomics quantifications can be useful for diabetic monitoring before and after cell therapy. Cell therapy is an alternative approach to achieve diabetes treatments goals including insulin resistance amelioration, insulin independence reparation, and control of glycemia. OMICs approaches provide a comprehensive insight into the molecular mechanisms of cells features and functional mechanism of their genomics, transcriptomics, proteomics, and metabolomics profile which can be useful for their therapeutic application. As a modern technology for the detection and analysis of metabolites in biological samples, metabolomica can identify many of the metabolic and molecular pathways associated with diabetes and its following complications.

Repurposing of FDA-Approved NSAIDs for DPP-4 Inhibition as an Alternative for Diabetes Mellitus Treatment: Computational and in Vitro Study

A drug repurposing strategy could be a potential approach to overcoming the economic costs for diabetes mellitus (DM) treatment incurred by most countries. DM has emerged as a global epidemic, and an increase in the outbreak has led developing countries like Mexico, India, and China to recommend a prevention method as an alternative proposed by their respective healthcare sectors. Incretin-based therapy has been successful in treating diabetes mellitus, and inhibitors like sitagliptin, vildagliptin, saxagliptin, and alogliptin belong to this category. As of now, drug repurposing strategies have not been used to identify existing therapeutics that can become dipeptidyl peptidase-4 (DPP-4) inhibitors. Hence, this work presents the use of bioinformatics tools like the Activity Atlas model, flexible molecular docking simulations, and three-dimensional reference interaction site model (3D-RISM) calculations to assist in repurposing Food and Drug Administration (FDA)-approved drugs into specific nonsteroidal anti-inflammatory medications such as DPP-4 inhibitors. Initially, the Activity Atlas model was constructed based on the top scoring DPP-4 inhibitors, and then the model was used to understand features of nonsteroidal anti-inflammatory drugs (NSAIDs) as a function of electrostatic, hydrophobic, and active shape features of DPP-4 inhibition. The FlexX algorithm was used to infer protein-ligand interacting residues, and binding energy, to predict potential draggability towards the DPP-4 mechanism of action. 3D-RISM calculations on piroxicam-bound DPP-4 were used to understand the stability of water molecules at the active site. Finally, piroxicam was chosen as the repurposing drug to become a new DPP-4 inhibitor and validated experimentally using fluorescence spectroscopy assay. These findings are novel and provide new insights into the role of piroxicam as a new lead to inhibit DPP-4 and, taking into consideration the biological half-life of piroxicam, it can be proposed as a possible therapeutic strategy for treating diabetes mellitus.

Antioxidant and Anti-Diabetic Activities of Polysaccharides from Guava Leaves

Guava (Psidium guajava L., Myrtaceae) leaves have been used as a folk herbal tea to treat diabetes for a long time in Asia and North America. In this study, we isolated polysaccharides from guava leaves (GLP), and evaluated its antioxidant activity in vitro and anti-diabetic effects on diabetic mice induced by streptozotocin combined with high-fat diet. The results indicated that GLP exhibited good DPPH, OH, and ABTS free-radical scavenging abilities, and significantly lowered fasting blood sugar, total cholesterol, total triglycerides, glycated serum protein, creatinine, and malonaldehyde. Meanwhile, it significantly increased the total antioxidant activity and superoxide dismutase (SOD) enzyme activity in diabetic mice, as well as ameliorated the damage of liver, kidney, and pancreas. Thus, polysaccharides from guava leaves could be explored as a potential antioxidant or anti-diabetic agents for functional foods or complementary medicine.

Characteristics of Patients with Diabetes Initiating Sodium Glucose Co-transporter-2 Inhibitors (SGLT2i): Real-World Results from Three Administrative Databases in Japan

INTRODUCTION

The aim of this study was to evaluate the characteristics of new users of sodium glucose co-transporter-2 inhibitors (SGLT2i) in comparison with those of new users of other oral antidiabetic drugs (OADs) using data retrieved from three administrative databases in Japan.

METHODS

This study included adult patients from each database who started an OAD between 2014 and 2017. Outpatients who started SGLT2i therapy were included in the SGLT2i cohort. The remaining outpatients were grouped according to the OAD class of their earliest initial prescription after no use of the index OAD during the 6-month pre-index period. Diabetes-related complications were evaluated using the Diabetes Complication Severity Index.

RESULTS

In total, 176,355 patients in the hospital-based administrative database (H-dataset), 98,361 in the pharmacy claims database (P-dataset) and 37,786 in the insurance claims database (I-dataset) were analyzed. In the H-dataset, SGLT2i users, compared with users of other OADs, tended to be younger (mean age at index: 57.7 vs. 60.3-69.2 years) and to have a higher prevalence of hypercholesterolemia (73.5 vs. 55.2-71.4%), a higher mean body weight (74.4 vs. 60.5-70.8 kg), a higher body mass index (27.6 vs. 23.5-26.4 kg/m²) and a higher glycated hemoglobin level (8.4 vs. 7.4-8.1%). There were no distinct differences in the prevalence of complications between SGLT2i users and users of other OADs in the H-dataset. Similar trends were noted in the other datasets.

CONCLUSION

Patients initiating SGLT2i therapy differed in several characteristics from new users of other OADs. SGLT2i were prescribed more frequently to younger patients, those at increased cardiovascular risk or those with poorer glycemic control.

FUNDING

Astellas Pharma Inc., Tokyo, Japan.

Anti-inflammatory Action of Metformin with Respect to CX3CL1/CX3CR1 Signaling in Human Placental Circulation in Normal-Glucose Versus High-Glucose Environments

Upregulation of chemokine CX3CL1 and its receptor CX3CR1 occurs in the diabetic human placenta. Metformin, an insulin-sensitizing biguanide, is used in the therapy of diabetic pregnancy. By preventing the activation of NF-κB, metformin exhibits anti-inflammatory properties. We examined the influence of hyperglycemia (25 mmol/L glucose; HG group; N = 36) on metformin-mediated effects on CX3CL1 and TNF-α production by placental lobules perfused extracorporeally. Additionally, CX3CR1 expression and contents of CX3CR1, TNF-α receptor 1 (TNFR1), and NF-κB proteins in the placental tissue were evaluated. Placentae perfused under normoglycemia (5 mmol/L glucose; NG group; N = 36) served as the control. Metformin (2.5 and 5.0 mg/L; subgroups B and C) lowered the production of CX3CL1 and TNF-α in a dose-dependent and time-dependent manner. Hyperglycemia did not weaken the strength of these metformin effects. Moreover, CX3CL1 levels after perfusion with 5.0 mg/L metformin were reduced by 33.28 and 33.83% (at 120 and 150 min, respectively) in the HG-C subgroup versus 24.98 and 23.66% in the NG-C subgroup, which indicated an augmentation of the metformin action over time in hyperglycemia. CX3CR1 expression was significantly higher in the HG-B and HG-C subgroups compared to that in the NG-B and NG-C subgroups. Increased CX3CR1 protein content in the placental lysates was observed in subgroups B and C. The two higher metformin concentrations significantly decreased the levels of NF-κBp65 protein content in both groups. However, the decrease was significantly stronger in hyperglycemia. TNFR1 upregulation in the HG group was not affected by metformin. Further studies on metformin therapy during pregnancy are needed, including safety issues.

Requirements of an Application to Monitor Diet, Physical Activity and Glucose Values in Patients with Type 2 Diabetes: The Diameter

Adherence to a healthy diet and regular physical activity are two important factors in sufficient type 2 diabetes mellitus management. It is recognized that the traditional treatment of outpatients does not meet the requirements for sufficient lifestyle management. It is hypothesised that a personalized diabetes management mHealth application can help. Such an application ideally measures food intake, physical activity, glucose values, and medication use, and then integrates this to provide patients and healthcare professionals insight in these factors, as well as the effect of lifestyle on glucose values in daily life. The lifestyle data can be used to give tailored coaching to improve adherence to lifestyle recommendations and medication use. This study describes the requirements for such an application: the Diameter. An iterative mixed method design approach is used that consists of a cohort study, pilot studies, literature search, and expert meetings. The requirements are defined according to the Function and events, Interactions and usability, Content and structure and Style and aesthetics (FICS) framework. This resulted in 81 requirements for the dietary (n = 37), activity and sedentary (n = 15), glycaemic (n = 12), and general (n = 17) parts. Although many applications are currently available, many of these requirements are not implemented. This stresses the need for the Diameter as a new personalized diabetes application.

The apelin/APJ system as a therapeutic target in metabolic diseases

INTRODUCTION

Apelin, a bioactive peptide, is the endogenous ligand of APJ, a G protein-coupled receptor which is widely expressed in peripheral tissues and in the central nervous system. The apelin/APJ system is involved in the regulation of various physiological functions and is a therapeutic target in different pathologies; the development of APJ agonists and antagonists has thus increased. Area covered: This review focuses on the in vitro and in vivo metabolic effects of apelin in physiological conditions and in the context of metabolic diseases. Expert opinion: In experimental models, novel APJ agonists are efficient in vivo, to treat metabolic diseases and associated complications. However, more clinical trials are necessary to determine whether molecules that target APJ could become an alternative therapeutic strategy in the treatment of metabolic diseases and associated complications.

Safety and Mode of Action of Diabetes Medications in comparison with 5-Aminolevulinic Acid (5-ALA)

5-Aminolevulinic acid (5-ALA) is a delta amino acid naturally present in every living cell of the human body. 5-ALA is produced in the mitochondria as the first product of the porphyrin synthesis pathway and composes heme; exogenously supplemented 5-ALA helps in upregulating mitochondrial functions. Mitochondrial dysfunction has been associated with the pathophysiology of diabetes mellitus. Thus, in this review, we evaluate the mechanisms of action and adverse effects of common medications used to treat type 2 diabetes mellitus as well as 5-ALA including its mechanism and possible use in diabetes management.

V(v)-Schiff base species induce adipogenesis through structure-specific influence of genetic targets

Appropriately designed Schiff-base substrates enhance V(v)-bioavailability and insulin-mimetic biomolecular gene profiling, inducing adipogenesis in a structure-specific manner.

Monotherapy with Metformin versus Sulfonylureas and Risk of Cancer in Type 2 Diabetic Patients: A Systematic Review and Meta-Analysis

BACKGROUND

Accumulating evidence suggests that patients with type 2 diabetes mellitus and hyperinsulinemia are at an increased risk of developing malignancies. It remains to be fully elucidated whether the use of metformin, an insulin sensitizer, and/or sulfonylureas, insulin secretagogues, affects cancer incidence in subjects with type 2 diabetes mellitus.

OBJECTIVE

A systematic review and meta-analysis was performed to compare the risk of cancer incidence associated with monotherapy with metformin compared with monotherapy with sulfonylureas in type 2 diabetes mellitus patients.

METHODS

Search was performed throughout MEDLINE/PubMed, EMBASE, Google Scholar, Cochrane Central Register of Controlled Trials (CENTRAL), and ClinicalTrials.gov up until December 2018. In this meta-analysis, each raw data (unadjusted) and study-specific (adjusted) relative risks (RRs) was combined and the pooled unadjusted and adjusted RRs with the 95% CI were calculated using the random-effects model with inverse-variance weighting. Heterogeneity among the studies was evaluated using I ² statistics. Publication bias was evaluated using the funnel plot asymmetry test. The Newcastle-Ottawa scale (NOS) was used to assess the study quality.

RESULTS

A total of 8 cohort studies were included in the meta-analysis. Obvious heterogeneity was noted, and monotherapy with metformin was associated with a lower risk of cancer incidence (unadjusted RR = 0.74, 95% CI: 0.55-0.99, I ² = 97.89%, p < 0.00001; adjusted RR = 0.76, 95% CI: 0.54-1.07, I ² = 98.12%, p < 0.00001) compared with monotherapy with sulfonylurea, using the random-effects model with inverse-variance weighting.

CONCLUSIONS

According to this review, the monotherapy with metformin appears to be associated with a lower risk of cancer incidence than monotherapy with sulfonylurea in patients with type 2 diabetes. This analysis is mainly based on cohort studies, and our findings underscore the need for large-scale randomized controlled trials to establish the effect of metformin monotherapy, relative to sulfonylureas monotherapy on cancer.

Impact of Pharmacist-directed Counseling and Message Reminder Services on Medication Adherence and Clinical Outcomes in Type 2 Diabetes Mellitus

Introduction:

Medication nonadherence is the most common issue observed in the management of diabetes because of complex and lifelong therapy. The study aimed to assess the effect of pharmacist-directed counseling and daily text message reminder on medication adherence and clinical profile of patients with type II diabetes.

Materials and Methods:

This prospective, open-labeled, randomized control trial was carried out in outpatient medical department of a secondary care referral hospital. A total of 330 patients who met study criteria were enrolled and randomized into an intervention group (n = 165), received counseling and daily messages about medication intake and control group (n = 165), and usual care by physician. Medication adherence and clinical outcomes such as glycosylated hemoglobin (HbA1C), systolic blood pressure (SBP), low-density lipoprotein (LDL) cholesterol, triglyceride (TG) levels, and body mass index (BMI) were recorded at baseline and follow-up visits. Two-sample Wilcoxon rank sum test was used to compare the mean difference of medication adherence and paired t-test was used to compare clinical outcomes.

Results and Discussion:

The mean age of intervention and control groups were 57.1 ± 8.55 and 58.5 ± 8.53 years, respectively. The mean difference of medication adherence from baseline to second follow-up visit was significantly more in intervention group (12.2 ± 7.1%) compared to that in control group (0.75 ± 10.2 %) with a P < 0.001. From baseline to second follow-up visit, HbA1C (7.79 ± 0.67 to 6.91 ± 0.83 %), SBP (136.75 ± 20.09 to 126.23 ± 18.22 mm Hg), and LDL cholesterol (104.14 ± 26.23 to 98.29 ± 20.87 mg/dL) levels were significantly reduced in intervention group compared to that in control group with a P < 0.01. No significant improvement was observed in TG (169± 33.71 to 168 65 ± 33.90 mg/dL) and BMI (27.9 ± 4.21 to 27.1 ± 3.12 Kg/m²) levels from baseline to second follow-up visit.

Conclusion:

Pharmacist-directed patient counseling combined with message reminder showed a greater effect on the improvement of medication adherence and control of glycemia, blood pressure, and lipid profile in diabetes.

Spondias tuberosa inner bark extract exert antidiabetic effects in streptozotocin-induced diabetic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetes mellitus (DM) is one of the most important medical emergencies of the 21st century. However, commercially available oral drugs with antidiabetic properties have been limited because of potential side effects, such as: hypoglycemia, weight gain, hepatic dysfunction and abdominal discomfort. As well as antidiabetic drugs, many types of medicinal herbal supplements are utilized as alternative treatments for DM and related comorbidities. Spondias tuberosa Arruda (Anacardiaceae), popularly known as "umbu", has been used in traditional medicine to treat a vast range of diseases, including DM, infections, digestive disorders, diarrhea and menstrual abnormalities.

AIM OF THE STUDY

This study evaluated the effect of the hydroethanolic extract of the inner stem bark of Spondias tuberosa (EEStb) in streptozotocin-induced diabetic rats.

MATERIALS AND METHODS

Diabetes was induced in rats by a single injection of STZ (40 mg/kg i.p.). Diabetic rats were treated with 250 mg/kg or 500 mg/kg of the EEStb for 21 days. Water intake, urinary volume, body weight, as well as biochemical parameters, such as cholesterol total (TC), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), hepatic and muscle glycogen urea, alanine and aspartate aminotransferase, total protein, albumin, and glucose blood levels, were analyzed. We also determined the hepatic antioxidant state, as well as both of insulin and glucose tolerance.

RESULTS

The extract was evaluated by HPLC, and the major components of EESTb were identified (i.e. gallic acid and quercetin). The 500 mg/kg dosage of EEStb significantly decreased fasting blood glucose and post-prandial glucose. The EEStb also reduced urinary volume, food and water intake, as well as decreased body weight gain. Diabetic rats that received EEStb had a lower loss of muscle mass and white adipose tissue. Additionally, EEStb improved the urinary excretion of urea and glucose. The extract significantly decreased triglycerides, total cholesterol and VLDL in diabetic rats. However, no significant effect was observed on the levels of total and HDL cholesterol. EEStb treatment prevented hepatotoxic diabetic-induced, improved GSH:GSSG ratio, SOD and CAT activity as well as reduced nitrite and TBARs levels.

CONCLUSIONS

Our results demonstrate that EEStb has antioxidant and hepatoprotective effects as well as improves insulin sensibility in diabetic rats. This indicates that S. tuberosa could be a potential resource for alternative therapies in the treatment of hyperglycemic conditions. These results also support the use of EEStb in ethnomedicine for the management of diabetes.

Amelioration effects of nanoencapsulated triterpenoids from petri dish-cultured Antrodia cinnamomea on reproductive function of diabetic male rats

PURPOSE

Nanoencapsulated triterpenoids from petri dish-cultured Antrodia cinnamomea (PAC) and its amelioration effects on reproductive function in diabetic rats were investigated.

MATERIALS AND METHODS

PAC encapsulated in silica-chitosan nanoparticles (Nano-PAC) was prepared by the biosilicification method. The diabetic condition in male Sprague Dawley rats was induced by high-fat diet and streptozotocin (STZ). Three different doses of Nano-PAC (4, 8, and 20 mg/kg) were administered for 6 weeks. Metformin and control of nanoparticles (Nano-con) were taken as positive and negative controls, respectively.

RESULTS

The average particle size was ~79.46±1.63 nm, and encapsulation efficiency was ~73.35%±0.09%. Nano-PAC administration improved hyperglycemia and insulin resistance. In addition, Nano-PAC ameliorated the morphology of testicular seminiferous tubules, sperm morphology, motility, ROS production, and mitochondrial membrane potential. Superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) antioxidant, as well as testosterone, luteinizing hormone (LH), and follicle stimulating hormone (FSH) were increased, whereas proinflammatory cytokines TNF-α, IL-6, and IFN-γ were decreased.

CONCLUSION

In the present study, we successfully nanoencapsulated PAC and found that a very low dosage of Nano-PAC exhibited amelioration effects on the reproductive function of diabetic rats.

"Diabetes and Metabolism Disorders Medicinal Plants: A Glance at the Past and a Look to the Future 2018": Antihyperglycemic Activity of Hamelia patens Jacq. Extracts

Diabetes is one the world's most widespread diseases, affecting over 327 million people and causing about 300,000 deaths annually. Despite great advances in prevention and therapy, existing treatments for this disorder have serious side effects. Plants used in traditional medicine represent a valuable source in the search for new medicinal compounds. Hamelia patens Jacq. has been used for treating diabetes and, so far, no reports have been made on the in vivo antihyperglycemic activity of this plant. The present study on H. patens aimed to test the antihyperglycemic effect of repeated administrations of the crude and fractional methanolic extracts (CME and FME, respectively) on rats with hyperglycemia induced by streptozotocin. After 10 administrations (20 days), each extract had lowered blood glucose to a normal level. The extracts produced effects similar to metformin. Of the five compounds identified by chromatographic analysis of the extracts, epicatechin and chlorogenic acid demonstrated antihyperglycemic effect. The antioxidant activity of the extracts was evidenced by their IC50 values (51.7 and 50.7 μg/mL, respectively). The LD50≥2000 mg/Kg suggests low toxicity for both CME and FME. Thus, considering that the antihyperglycemic and antioxidant effects of metformin and extracts from H. patens were comparable, the latter may be efficacious for treating diabetes.

Emerging role of nutrition and the non-coding landscape in type 2 diabetes mellitus: A review of literature

With the advent of recent advances in molecular techniques and whole genome sequencing, we have come to know that the non-coding landscape (including non-coding RNAs, tRNAs and even telomeres) plays a major role in the regulation of cellular processes. Furthermore, the deregulation of this landscape has been found to contribute to and even bring about the pathogenesis of a large number of diseases. One of such diseases is diabetes mellitus (type 2 specifically) whose incidence rate and global burden is constantly increasing. Nutrition has been proven to be a key player in the development, onset and control of type 2 diabetes mellitus. Additionally, non-coding DNA based molecular markers are emerging as biomarkers of T2D, susceptibility, and perhaps dietary supplements can modulate non-coding DNA based markers expression and function in T2D management. In this review, we provide a brief overview of the developmental origins and genetics of type 2 diabetes mellitus, how each component of the non-coding landscape contributes to the development and progression of the disease and finally we discuss how dietary interventions modulate the non-coding landscape in T2D.

Mechanism of antidiabetic and synergistic effects of ginseng polysaccharide and ginsenoside Rb1 on diabetic rat model

Ginseng polysaccharides (GP) have been reported to modulate gut microbiota, and ginsenoside Rb1 is known to display significant hypoglycemic activity. However, the synergistic effect of Rb1 and GP when applied to diabetic treatment remains largely unknown. Male rats were divided into ten groups: blank group (B-Group), model group (D-Group), Rb1 group (Rb1-Group), CK group (CK-Group), GP groups and GP + Rb1 groups in dosage of high, middle and low (H-Group, M-Group, L-Group, H-Rb1-Group, M-Rb1-Group, and L-Rb1-Group). CK-Group, GP groups and Rb1 group were fed CK, GP and Rb1 for 30 days, respectively. GP + Rb1 groups were fed GP on the initial 15 days and GP and Rb1 on the final 15 days. The fasting glucose of all groups was measured every five days. The transformation of Rb1 in vitro by rat intestinal microflora, which was collected from the B-Group, D-Group and GP groups on the 15th day, was investigated using HPLC and RRLC-Q-TOF/MS. Analyses the of 16S rRNA gene of the fecal bacterial population and fecal β-glucosidase activity were conducted among the B-Group, D-Group and H-Group. Compared with those of rats in the D-Group, the fasting glucose levels of rats in the CK-Group and H-Rb1-Group decreased highest. During transformation of Rb1 by diabetic rat intestinal microflora, five transformed products, including ginsenoside Rd, F2, CK, gypenoside XVII (G-XVII), and LXXV (G-LXXV), as well as three transformation pathways, were identified. When a high dose of GP was fed to diabetic rats for 15 days, the formation of intermediates, including G-XVII and G-LXXV was inhibited, and only one pathway (Rb1→Rd→F2→CK) was identified. Moreover, the biotransformation rate of CK increased from 14.0% to 86.7% after 8 h of cultivation. GP reinstated the perturbed holistic gut microbiota and promoted fecal β-d-glucosidase activity. Ginsenoside Rb1 and GP shows synergistic effects when applied to diabetic treatment and may be developed as a potential antidiabetic drug.

Hematopoietically expressed homeobox gene is associated with type 2 diabetes in KK Cg-Ay/J mice and a Taiwanese Han Chinese population

Diabetes mellitus (DM) is a chronic disease. The KK Cg-A^y/J (KK-A^y) mouse is an animal model to study type 2 diabetes mellitus (T2D) disease. The present study assessed the expression of hematopoietically expressed homeobox (HHEX) protein in liver tissues of different age groups of mice (6, 16 and 42 weeks) by immunohistochemistry (IHC). The results demonstrated a significant decrease in the percentage of HHEX-positive cells in KK-A^y mice as compared with that in KK-α/α control mice. Furthermore, in Taiwan's Han Chinese population, genotypic and allelic frequency distributions of the rs61862780 single-nucleotide polymorphism (SNP) in the HHEX gene were investigated. The results demonstrated that in the rs61862780 SNP of the 3′-untranslated region (UTR) of HHEX, the frequency of the CC genotype was higher in patients (6.0%) than in controls (2.7%), while the TT genotype frequency was about equal. In the same SNP, the frequency of the C allele was higher in patients (21.0%) than in controls (17.3%), while the T allele frequency was about equal. These results may pave the road for exploring the KK-A^y mouse model and the HHEX SNP rs61862780, which was correlated with the susceptibility to T2D in a Chinese population. Based on these findings, an association of HHEX gene expression with pathological features of T2D was indicated.

Lower glycemic indices and lipid profile among type 2 diabetes mellitus patients who received novel dose of Silybum marianum (L.) Gaertn. (silymarin) extract supplement: A Triple-blinded randomized controlled clinical trial

OBJECTIVE

This randomized clinical trial was conducted to evaluate the effects of silymarin supplementation on glycemic indices and serum lipid profile in type 2 diabetes mellitus (T2DM) patients.

METHODS

40 T2DM patients (twenty male and twenty female), 25-50 years of age and on stable medication, were recruited for the present paralleled, randomized, triple-blinded, placebo-controlled clinical trial. The participants were randomly assigned to the silymarin or placebo groups, in which the patients either received 140 mg of silymarin, thrice daily (n = 20) or placebo (n = 20) for 45 days. Anthropometric and dietary intake data were collected at the baseline and end of the trial. Fasting blood samples were collected, and glycemic indices and lipid profile were determined at baseline, as well as the end of the study.

RESULTS

Silymarin supplementation led to significant reduction in fasting blood sugar, serum insulin, homeostatic model assessment for insulin resistance, serum triglyceride and triglyceride to high-density lipoprotein cholesterol ratio as compared to the placebo, by 11.01, 14.35, 25.92, 23.7 and 27.67% respectively. There was significant increase in high-density lipoprotein cholesterol levels and quantitative insulin sensitivity check index in the silymarin group as compared to the placebo group, by 6.88 and 5.64% respectively, (p < 0.05). Total cholesterol and low-density lipoprotein cholesterol concentrations significantly decreased in the silymarin group as compared to the baseline, by 7.93 (p = 0.001) and 7.15% (p = 0.02), respectively.

CONCLUSION

Silymarin supplementation may improve the glycemic indices and lipid profiles of T2DM patients. More studies are needed to validate the adjunct use of silymarin for metabolic control of T2DM patients.

Recent progress of sodium-glucose transporter 2 inhibitors as potential antidiabetic agents

SGLT2 inhibitors were promising and novel antidiabetic drugs which suppressed glucose reabsorption and increased urinary glucose exertion. This review paper are aimed to summarize the recent progress of SGLT2 inhibitors during the last 5 years. This paper first summarizes the information of SGLT2 inhibitors, including mechanism, evolution and then focuses on the recent efforts on structure-activity relationships and structural optimization of SGLT2 inhibitors. Finally, the corresponding clinical therapeutic efficacy and adverse drug reaction in patients with Type 2 diabetes are discussed in detail.

Harnessing insulin- and leptin-induced oxidation of PTP1B for therapeutic development

The protein tyrosine phosphatase PTP1B is a major regulator of glucose homeostasis and energy metabolism, and a validated target for therapeutic intervention in diabetes and obesity. Nevertheless, it is a challenging target for inhibitor development. Previously, we generated a recombinant antibody (scFv45) that recognizes selectively the oxidized, inactive conformation of PTP1B. Here, we provide a molecular basis for its interaction with reversibly oxidized PTP1B. Furthermore, we have identified a small molecule inhibitor that mimics the effects of scFv45. Our data provide proof-of-concept that stabilization of PTP1B in an inactive, oxidized conformation by small molecules can promote insulin and leptin signaling. This work illustrates a novel paradigm for inhibiting the signaling function of PTP1B that may be exploited for therapeutic intervention in diabetes and obesity.

The activity of protein tyrosine phosphatase PTP1B, a major metabolic regulator, depends on its oxidation state. Here the authors identify and characterize a small molecule that targets the oxidized, inactive form of PTP1B, suggesting a new therapeutic approach to diabetes and obesity.

BPN, a marine-derived PTP1B inhibitor, activates insulin signaling and improves insulin resistance in C2C12 myotubes

Insulin resistance is a key feature of type 2 diabetes mellitus (T2DM) and is characterized by defects in insulin signaling. Protein tyrosine phosphatase 1B (PTP1B) is a major negative regulator of insulin signaling cascade and has attracted intensive investigation in recent T2DM therapy study. BPN, a marine-derived bromophenol compound, was isolated from the red alga Rhodomela confervoides. This study investigated the effects of BPN on the insulin signaling pathway in insulin-resistant C2C12 myotubes by inhibiting PTP1B. Molecular docking study and analysis of small- molecule interaction with PTP1B all showed BPN inhibited PTP1B activity via binding to the catalytic site through hydrogen bonds. We then found that BPN permeated into C2C12 myotubes, on the one hand, activated insulin signaling in an insulin-independent manner in C2C12 cells; on the other hand, ameliorated palmitate-induced insulin resistance through augmenting insulin sensitivity. Moreover, our studies also showed that PTP1B inhibition by BPN increased glucose uptake in normal and insulin-resistant C2C12 myotubes through glucose transporter 4 (GLUT4) translocation. Taken together, BPN activates insulin signaling and alleviates insulin resistance and represents a potential candidate for further development as an antidiabetic agent.

A potent, selective, and orally bioavailable inhibitor of the protein-tyrosine phosphatase PTP1B improves insulin and leptin signaling in animal models

The protein-tyrosine phosphatase PTP1B is a negative regulator of insulin and leptin signaling and a highly validated therapeutic target for diabetes and obesity. Conventional approaches to drug development have produced potent and specific PTP1B inhibitors, but these inhibitors lack oral bioavailability, which limits their potential for drug development. Here, we report that DPM-1001, an analog of the specific PTP1B inhibitor trodusquemine (MSI-1436), is a potent, specific, and orally bioavailable inhibitor of PTP1B. DPM-1001 also chelates copper, which enhanced its potency as a PTP1B inhibitor. DPM-1001 displayed anti-diabetic properties that were associated with enhanced signaling through insulin and leptin receptors in animal models of diet-induced obesity. Therefore, DPM-1001 represents a proof of concept for a new approach to therapeutic intervention in diabetes and obesity. Although the PTPs have been considered undruggable, the findings of this study suggest that allosteric PTP inhibitors may help reinvigorate drug development efforts that focus on this important family of signal-transducing enzymes.

Bioanalytical methods for the detection of antidiabetic drugs: a review

Type 2 diabetes mellitus, a disease which prevalence has been progressively increasing worldwide, is characterized by chronic hyperglycemia resulting from the combination of inappropriate insulin secretion and/or resistance to insulin action. If left uncontrolled, diabetes is associated with complications such as dysfunction and failure of various organs, and even premature death. Along with lifestyle-modification strategies, several classes of oral antidiabetic agents can be employed for glycemic control. Thus, therapeutic drug monitoring of these drugs is essential to maintain appropriate treatment. This review discusses the most frequently employed analytical techniques and sample preparation systems to obtain a reliable and trustworthy method to quantify antidiabetic drugs in biological matrices. An adequate choice of internal standard, ideal chromatography conditions and most suitable analytical detector are reported.

Factors Associated with a Prolonged Length of Hospital Stay in Patients with Diabetic Foot: A Single-Center Retrospective Study

BACKGROUND

We conducted this study to identify factors that may prolong the length of the hospital stay (LHS) in patients with diabetic foot (DF) in a single-institution setting.

METHODS

In this single-center retrospective study, we evaluated a total of 164 patients with DF, and conducted an intergroup comparison of their baseline demographic and clinical characteristics, including sex, age, duration of diabetes, smoking status, body mass index, underlying comorbidities (e.g., hypertension or diabetic nephropathy), wound characteristics,type of surgery, the total medical cost, white blood cell (WBC) count, C-reactive protein (CRP) levels, erythrocyte sedimentation rate, and albumin, protein, glycated hemoglobin, and 7-day mean blood glucose (BG) levels.

RESULTS

Pearson correlation analysis showed that an LHS of >5 weeks had a significant positive correlation with the severity of the wound (r=0.647), WBC count (r=0.571), CRP levels (r=0.390), DN (r=0.020), and 7-day mean BG levels (r=0.120) (P<0.05). In multiple regression analysis, an LHS of >5 weeks had a significant positive correlation with the severity of the wound (odds ratio [OR]=3.297; 95% confidence interval [CI], 1.324-10.483; P=0.020), WBC count (OR=1.423; 95% CI, 0.046-0.356; P=0.000), CRP levels (OR=1.079; 95% CI, 1.015-1.147; P=0.014), albumin levels (OR=0.263; 95% CI, 0.113-3.673; P=0.007), and 7-day mean BG levels (OR=1.018; 95% CI, 1.001-1.035; P=0.020).

CONCLUSIONS

Surgeons should consider the factors associated with a prolonged LHS in the early management of patients with DF. Moreover, this should also be accompanied by a multidisciplinary approach to reducing the LHS.

Pharmacodynamics, pharmacokinetics and safety of multiple ascending doses of the novel dual glucose-dependent insulinotropic polypeptide/glucagon-like peptide-1 agonist RG7697 in people with type 2 diabetes mellitus

AIMS

To investigate the pharmacodynamics, pharmacokinetics and safety of multiple ascending doses of RG7697, a dual glucose-dependent insulinotropic polypeptide/glucagon-like peptide-1 agonist, in patients with type 2 diabetes mellitus (T2D).

METHODS

A total of 56 patients with T2D received once-daily subcutaneous (s.c.) injection of RG7697 (0.25-2.5 mg) or placebo for 14 days in a randomized, double-blind, dose-escalation study. Adverse events (AEs), vital signs, ECGs and routine laboratory variables were intensively monitored. Drug concentrations, fasting glycaemic variables, 24-hour glucose profiles, glycated haemoglobin (HbA1c) and antibody formation were measured. Several meal tolerance and gastric emptying tests were performed during the study.

RESULTS

Daily s.c. injections of RG7697 were well tolerated by the majority of participants with T2D. The most frequently reported AEs with RG7697 were diarrhoea, nausea and decreased appetite. Asymptomatic events of hypoglycaemia were relatively uniformly distributed across dose groups including placebo. Pharmacokinetic steady-state was achieved within 1 week. Meaningful reductions in fasting, postprandial and 24-hour plasma glucose profile were observed at doses ≥0.75 mg, and were associated with numerical decreases in HbA1c (-0.67% [2.5-mg dose] vs -0.21% [placebo]). Decrease in postprandial insulin at doses ≥1.1 mg suggested improvement in insulin sensitivity. Minimum delay in gastric emptying and body weight reductions numerically greater than placebo (- 3.0 kg vs -0.9 kg) were seen at the highest dose of 2.5 mg.

CONCLUSIONS

Daily doses of RG7697 for 2 weeks were well tolerated by the majority of patients with T2D. Pharmacokinetic data supported once-daily dosing and pharmacodynamic effect displayed dose-dependent reductions in fasting and postprandial plasma glucose, without increasing the risk of hypoglycaemia.

Antidiabetic Effect of Tibetan Medicine Tang-Kang-Fu-San on High-Fat Diet and Streptozotocin-Induced Type 2 Diabetic Rats

The aim of this study was to investigate the antidiabetic effects of a Tibetan medicine, Tang-Kang-Fu-San (TKFS), on experimental type 2 diabetes mellitus (T2DM) rats and to explore its underlying mechanisms. Firstly two major chemical compositions of TKFS, gallic acid and curcumin, were characterized by HPLC fingerprint analysis. Next T2DM in rats was induced by high-fat diet and a low-dose streptozotocin (STZ 35 mg/kg). Then oral gavage administration of three different doses of TKFS (0.3 g/kg, 0.6 g/kg, and 1.2 g/kg) was given to T2DM rats. Experimental results showed that TKFS dramatically reduced the levels of fasting blood glucose, fasting blood insulin, triglyceride, total cholesterol, LDL cholesterol, and HDL cholesterol, even though it did not alter the animal body weight. The downregulation of phosphorylation-AKT (p-AKT) and glucose transporter-4 (GLUT4) in skeletal muscle of T2DM rats was restored and abnormal pathological changes in pancreas tissues were also improved. Our work showed that TKFS could alleviate diabetic syndromes, maintain the glucose homeostasis, and protect against insulin resistance in T2DM rats, and the improvement of AKT phosphorylation and GLUT4 translocation in skeletal muscle would be one of its possible underlying mechanisms.