The role of sulphonylureas in the management of type 2 diabetes mellitus

Discovery of ZYDG2: A potent, selective, and safe GPR40 agonist for treatment of type 2 diabetes

GPR40/FFA1 receptor, predominantly expressed in pancreatic β-cells, mediates glucose-stimulated insulin secretion by free fatty acids. Fasiglifam-GPR40 agonist was terminated in phase III clinical trials due to adverse liver effects. ZYDG2 is identified as a novel, potent and selective agonist for GPR40, exhibiting EC50 of 41 nM and 17 nM in cell-based functional inositol 1-phosphate-ELISA assay and Ca2+ mobilization assay, respectively. ZYDG2 has demonstrated dose-dependent improvement in glucose tolerance tests and increased insulin secretion in neonatal streptozotocin Wistar rats. After repeated dose administration for 15 weeks, ZYDG2 showed efficacy without tachyphylaxis. ZYDG2 significantly increased the glucose infusion rate in a hyperglycemic clamp study and demonstrated antidiabetic efficacy in mice models of type 2 diabetes mellitus, which was not reported for fasiglifam. ZYDG2 exhibited 60%-100% oral bioavailability across preclinical species, including mice, rats, dogs, and primates. Liver toxicity of fasiglifam was associated with its bile acid transporter inhibition, whereas ZYDG2 showed no inhibition (up to 300 μM). In rat acute toxicity studies, the maximum tolerated dose for ZYDG2 was 2000 mg/kg, whereas fasiglifam was tolerable up to 300 mg/kg. Fasiglifam treatment at 300 mg/kg for 10 days in rats caused a significant rise in serum alanine aminotransferase, aspartate aminotransferase, and total bilirubin level along with vacuolation, ulceration, and red foci in liver tissue, whereas ZYDG2 showed no liver toxicity up to 300 mg/kg. Moreover, after 28 days of repeated dose treatment of ZYDG2, the no-observed-adverse-effect-level was found to be 300 mg/kg. This robust data conclusively demonstrates that ZYDG2 is a highly promising and unequivocally safe therapeutic candidate for the treatment of type 2 diabetes. SIGNIFICANCE STATEMENT: ZYDG2 is a potent, selective, and safe GPR40 agonist which may be a promising candidate for the treatment of type 2 diabetes as it has shown better efficacy and safety profile compared with fasiglifam.

Glibenclamide targets MDH2 to relieve aging phenotypes through metabolism-regulated epigenetic modification

Mitochondrial metabolism-regulated epigenetic modification is a driving force of aging and a promising target for therapeutic intervention. Mitochondrial malate dehydrogenase (MDH2), an enzyme in the TCA cycle, was identified as an anti-aging target through activity-based protein profiling in present study. The expression level of MDH2 was positively correlated with the cellular senescence in Mdh2 knockdown or overexpression fibroblasts. Glibenclamide (Gli), a classic anti-glycemic drug, was found to inhibit the activity of MDH2 and relieve fibroblast senescence in an MDH2-dependent manner. The anti-aging effects of Gli were also further validated in vivo, as it extended the lifespan and reduced the frailty index of naturally aged mice. Liver specific Mdh2 knockdown eliminated Gli's beneficial effects in naturally aged mice, reducing p16INK4a expression and hepatic fibrosis. Mechanistically, MDH2 inhibition or knockdown disrupted central carbon metabolism, then enhanced the methionine cycle flux, and subsequently promoted histone methylation. Notably, the tri-methylation of H3K27, identified as a crucial methylation site in reversing cellular senescence, was significantly elevated in hepatic tissues of naturally aged mice with Mdh2 knockdown. Taken together, these findings reveal that MDH2 inhibition or knockdown delays the aging process through metabolic-epigenetic regulation. Our research not only identified MDH2 as a potential therapeutic target and Gli as a lead compound for anti-aging drug development, but also shed light on the intricate interplay of metabolism and epigenetic modifications in aging.

Indigenous Medicinal Plants Used in the Management of Diabetes in Africa: 5 Years (2019-2024) in Perspective

(1) Background: The utilization of medicinal plants in the management of diabetes is of great importance to the health of the indigenous population on the African continent. The high cost of orthodox conventional medicines coupled with the perceived side effects encourages the high patronage of indigenous medicinal plants in the management of this metabolic disorder. We conducted a review on the indigenous African medicinal plants that could be useful in preclinical and clinical trials in the field of diabetes mellitus research. (2) Methods: Data were mined from research articles published and associated with the use of medicinal plants in the management of diabetes on the African continent (from January 2019 to March 2024). Literature from ethnobotanical studies on the African continent was searched from the Google Scholar, SCOPUS, Medline, Web of Science and PubMed databases. We employed the following keywords: "indigenous plants", "diabetes in Africa" and "antidiabetic effect of medicinal plants". (3) Results: A total of 52 medicinal plants belonging to 31 families were recorded in this study. Amaryllidaceae (14.28%), Fabaceae (9.52%) and Asteraceae (9.52%) were the most cited plant families. The frequently used indigenous medicinal plants on the African continent were Allium sativum L. (n = 6), Olea europaea L. (n = 6), Azadirachta indica A. Juss (n = 5), Allium cepa L. (n = 5) and Moringa oleifera Lam. (n = 5). The highly cited parts of the plant used in the management of diabetes were the leaves (45.55%), bark (14.44%) and bulbs (12.22%). The preferred methods of the preparation of herbal medicines were decoction (45.23%) and infusion (25%). Oral (52.32%) was the preferred route of the administration of herbal medicine on the African continent. (4) Conclusions: The data revealed some similarities in the way countries on the African continent manage diabetes. This interesting observation will assist in our quest towards obtaining a standardized protocol using indigenous medicinal plants to combat diseases on the African continent.

Skin-Related Adverse Reactions Induced by Oral Antidiabetic Drugs-A Review of Literature and Case Reports

Type 2 diabetes (T2DM) is a chronic metabolic disease with a steadily increasing prevalence worldwide. Diabetes affects the function of many organs, including the skin. Pharmacotherapy for T2DM is mainly based on oral hypoglycemic drugs. The therapeutic strategy is chosen taking into account the individual patient's characteristics, among other comorbidities. Antidiabetic drugs can induce cutaneous adverse reactions (CADRs) ranging in severity from mild erythema to serious disorders such as DRESS or Stevens-Johnson syndrome. CADRs can result from hypersensitivity to the drug but can also be related to the mechanism of action of the drug or cross-reactivity with drugs of similar structure. This paper reviews CADRs induced by oral antidiabetic drugs, considering their dermatological manifestations and possible pathomechanisms. Particular attention was paid to specific dermatological conditions such as dipeptidylpeptidase 4 inhibitor-associated bullous pemphigoid or Fournier's gangrene associated with sodium-glucose cotransporter 2 inhibitor therapy. Knowledge of the dermatological manifestations of CADRs is important in clinical practice. Recognition of a skin lesion resulting from an adverse drug reaction allows for appropriate management, which in this case is primarily related to drug discontinuation. This is particularly important in the treatment of T2DM since this disease has a high prevalence in the elderly, who are at higher risk of adverse drug reactions.

To Explore the Putative Molecular Targets of Diabetic Nephropathy and their Inhibition Utilizing Potential Phytocompounds

BACKGROUND

This review critically addresses the putative molecular targets of Diabetic Nephropathy (DN) and screens effective phytocompounds that can be therapeutically beneficial, and highlights their mechanistic modalities of action.

INTRODUCTION

DN has become one of the most prevalent complications of clinical hyperglycemia, with individual-specific variations in the disease spectrum that leads to fatal consequences. Diverse etiologies involving oxidative and nitrosative stress, activation of polyol pathway, inflammasome formation, Extracellular Matrix (ECM) modifications, fibrosis, and change in dynamics of podocyte functional and mesangial cell proliferation adds up to the clinical complexity of DN. Current synthetic therapeutics lacks target-specific approach, and is associated with the development of inevitable residual toxicity and drug resistance. Phytocompounds provides a vast diversity of novel compounds that can become an alternative therapeutic approach to combat the DN.

METHODS

Relevant publications were searched and screened from research databases like GOOGLE SCHOLAR, PUBMED and SCISEARCH. Out of 4895 publications, the most relevant publications were selected and included in this article.

RESULT

This study critically reviews over 60 most promising phytochemical and provides with their molecular targets, that can be of pharmacological significance in context to current treatment and concomitant research in DN.

CONCLUSION

This review highlights those most promising phytocompounds that have the potential of becoming new safer naturally-sourced therapeutic candidates and demands further attention at clinical level.

Differentiation-Promoting Effects of Okeaniamides A and B from an Okeania sp. Marine Cyanobacterium on Preadipocytes

The linear lipopeptides okeaniamide A (1) and okeaniamide B (2) were isolated from an Okeania sp. marine cyanobacterium collected in Okinawa. The structures of these compounds were established by spectroscopic analyses, and the absolute configurations were elucidated based on a combination of chemical degradations, Marfey's analysis, and derivatization reactions. Okeaniamide A (1) and okeaniamide B (2) dose-dependently promoted the differentiation of mouse 3T3-L1 preadipocytes in the presence of insulin.

Extraction, identification, and starch-digestion inhibition of phenolics from Euryale ferox seed coat

BACKGROUND

Euryale ferox is an important cash crop and valuable tonic in traditional medicine. The seeds of E. ferox are rich in starch, which is hard to digest, and the digestion speed is significantly slower than that of rice starch. The goal of this study was to evaluate the effects of E. ferox seed-coat phenolics (EFCPs) on the digestion of E. ferox seed starch.

RESULTS

EFCPs were extracted and identified by ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. We optimized the extraction parameters, and the final extraction yield was about 1.49%. We identified seven phenolics from the E. ferox seed-coat extracts: gallic acid, digalloylhexoside, catechin, procyanidin B2, epicatechin, ellagic acid, and epicatechin gallate. Quantitative analysis results showed that the E. ferox seed phenolics mainly distributed in the seed coat and the gallic acid, digalloylhexoside, and epicatechin gallate were three main phenolic compounds. The phenolics displayed strong inhibitory activities on α-glucosidase and α-amylase with an IC₅₀ of 3.25 μg mL^-1 and 1.36 mg mL^-1 respectively. Furthermore, these phenolics could interact with starch by hydrogen bonds, which might make its starch more difficult to digest.

CONCLUSION

Our investigation suggests that the EFCPs can strongly inhibit the digestion of E. ferox seed starch by inhibiting the α-amylase and α-glucosidase activities and interacting with starch by hydrogen bonds; therefore, E. ferox seeds have a promising application prospect in foods for hypoglycemia. © 2023 Society of Chemical Industry.

Unlocking the Full Potential of SGLT2 Inhibitors: Expanding Applications beyond Glycemic Control

The number of diabetic patients has risen dramatically in recent decades, owing mostly to the rising incidence of type 2 diabetes mellitus (T2DM). Several oral antidiabetic medications are used for the treatment of T2DM including, α-glucosidases inhibitors, biguanides, sulfonylureas, meglitinides, GLP-1 receptor agonists, PPAR-γ agonists, DDP4 inhibitors, and SGLT2 inhibitors. In this review we focus on the possible effects of SGLT2 inhibitors on different body systems. Beyond the diabetic state, SGLT2 inhibitors have revealed a demonstrable ability to ameliorate cardiac remodeling, enhance myocardial function, and lower heart failure mortality. Additionally, SGLT2 inhibitors can modify adipocytes and their production of cytokines, such as adipokines and adiponectin, which enhances insulin sensitivity and delays diabetes onset. On the other hand, SGLT2 inhibitors have been linked to decreased total hip bone mineral deposition and increased hip bone resorption in T2DM patients. More data are needed to evaluate the role of SGLT2 inhibitors on cancer. Finally, the effects of SGLT2 inhibitors on neuroprotection appear to be both direct and indirect, according to scientific investigations utilizing various experimental models. SGLT2 inhibitors improve vascular tone, elasticity, and contractility by reducing oxidative stress, inflammation, insulin signaling pathways, and endothelial cell proliferation. They also improve brain function, synaptic plasticity, acetylcholinesterase activity, and reduce amyloid plaque formation, as well as regulation of the mTOR pathway in the brain, which reduces brain damage and cognitive decline.

Sulfonylurea Use in Patients with Type 2 Diabetes and COPD: A Nationwide Population-Based Cohort Study

We conducted this study to investigate the long-term outcomes of sulfonylurea (SU) use in patients with chronic obstructive pulmonary disease (COPD) and type 2 diabetes (T2D). We used propensity-score matching to identify 6008 pairs of SU users and nonusers from Taiwan's National Health Insurance Research Database from 1 January 2000 to 31 December 2017. Cox proportional hazard models were used to compare the risks of mortality, cardiovascular events, non-invasive positive pressure ventilation, invasive mechanical ventilation, bacterial pneumonia, lung cancer, and hypoglycemia between SU users and nonusers. In the matched cohorts, the mean follow-up time for SU users and nonusers was 6.57 and 5.48 years, respectively. Compared with nonusers, SU users showed significantly lower risks of mortality [aHR 0.53(0.48-0.58)], cardiovascular events [aHR 0.88(0.81-0.96)], non-invasive positive pressure ventilation [aHR 0.74(0.6-0.92)], invasive mechanical ventilation [aHR 0.57(0.5-0.66)], and bacterial pneumonia [aHR 0.78(0.7-0.87)]. A longer cumulative duration of SU use was associated with a lower risk of these outcomes. This nationwide cohort study demonstrated that SU use was associated with significantly lower risks of cardiovascular events, ventilation use, bacterial pneumonia, and mortality in patients with COPD and T2D. SU may be a suitable option for diabetes management in these patients.

Doctors' adherence to guidelines recommendations and glycaemic control in diabetic patients in Quetta, Pakistan: Findings from an observational study

Background

Poor control of diabetes mellitus (DM) is partly attributed to doctors' poor adherence to guidelines.

Objective

To evaluate doctors' adherence to pharmacotherapeutic recommendations of DM management guidelines and factors associated with guidelines adherence and glycaemic control.

Methods

This prospective observational study included 30 doctors who were treating DM patients in their private clinics in Quetta, Pakistan. On visit 1, a total of 600 prescriptions written by 30 enrolled doctors (20 patients per doctor) were noted along with patients' sociodemographic and clinical characteristics. American Diabetes Association guidelines was used as a reference. The prescriptions noted were judged for guidelines compliance. Of 600 enrolled patients, 450 patients (15 patients per doctor) were followed for one more visit and included in final analysis. Glycated hemoglobin (HbA1c) level noted one visit 2 was related with the respective prescription on visit 1. Data were analyzed by SPSS (version 23). A p-value <0.05 was considered statistically significant.

Results

Patients received a median of two antidiabetic drugs (range: 1-5). A total of 73.1% patients were on polytherapy. Metformin was the most frequently prescribed (88.4%) antidiabetic followed by gliptins (46.2%). A total of 41.6% prescriptions were judged guidelines compliant. In multivariate binary logistic regressions (MVBLR) analysis, chronic kidney disease (CKD) (OR = 0.422) and polytherapy (OR = 0.367) had statistically significant negative associations (p-value <0.05) with guidelines' compliant prescriptions. The group of doctors comprised of specialists and consultants wrote significantly (p-value = 0.004) high number of guidelines adherent prescriptions (mean rank = 20.25) than the group comprised of medical officers (mean rank = 11.34). On visit 2, only 39.5% patients were on goal glycemic levels. In MVBLR analysis, suffering from dyslipidemia (OR = 0.134) and CKD (OR = 0.111), receiving sulfonylurea (OR = 0.156) and guidelines' compliant prescription (OR = 4.195) were significantly (p-value <0 .05) associated with glycemic control.

Conclusion

Although guidelines compliant prescriptions produced better glycemic control, but doctors' adherence to guidelines and glycemic control were poor. Polytherapy and CKD emerged as risk factors for guidelines divergent prescriptions. Dyslipidemia, CKD and reception of sulfonylureas had negative association with glycemic control.

How fullerene derivatives (FDs) act on therapeutically important targets associated with diabetic diseases

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Five proteins related to diabetic disease were selected from Protein Data Bank.

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Binding scores were calculated for five proteins with 169 fullerene derivatives.

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Correlation between drug-like descriptors and binding scores activity was examined.

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The contribution of descriptors to protein-ligand binding was demonstrated.

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The QSARs models for prediction of binding scores activity were built.

Fullerene derivatives (FDs) belong to a relatively new family of nano-sized organic compounds. They are widely applied in materials science, pharmaceutical industry, and (bio) medicine. This research focused on the study of FDs in terms of their potential inhibitory effect on therapeutic targets associated with diabetic disease, as well as analysis of protein–ligand binding in order to identify the key binding characteristics of FDs.

Therapeutic drug compounds when entering the biological system usually inevitably encounter and interact with a vast variety of biomolecules that are responsible for many different functions in organisms. Protein biomolecules are the most important functional components and used in this study as target structures. The structures of proteins [(PDB ID: 1BMQ, 1FM6, 1GPB, 1H5U, 1US0)] belonging to the class of anti-diabetes targets were obtained from the Protein Data Bank (PDB). Protein binding activity data (binding scores) were calculated for the dataset of 169 FDs related to these five proteins. Subsequently, the resulting data were analyzed using various machine learning and cheminformatics methods, including artificial neural network algorithms for variable selection and property prediction.

The Quantitative Structure-Activity Relationship (QSAR) models for prediction of binding scores activity were built up according to five Organization for Economic Co-operation and Development (OECD) principles.

All the data obtained can provide important information for further potential use of FDs with different functional groups as promising medical antidiabetic agents. Binding scores activity can be used for ranking of FDs in terms of their inhibitory activity (pharmacological properties) and potential toxicity.

The mechanism of delaying starch digestion by luteolin

In this study, the mechanisms of the delay of starch digestion by luteolin were revealed by studying the luteolin-PPA (porcine pancreatic α-amylase) interaction and luteolin-starch interaction. The luteolin-PPA interaction was investigated by inhibitory kinetics analysis, fluorescence quenching, circular dichroism (CD), Fourier transform infrared (FT-IR) spectroscopy and molecular docking. The results of the inhibitory kinetics revealed that luteolin was a mixed-type inhibitor of PPA and that the inhibitory action was reversible. Fluorescence spectroscopy (including fluorescence quenching and thermodynamics) and molecular docking analyses indicated that hydrogen bonds and hydrophobic forces were the main forces between PPA and luteolin. CD and FT-IR spectroscopy analyses showed that the interaction between luteolin and PPA changed the secondary structure of PPA and induced a decline in its activity. In addition, the luteolin-starch interaction was also studied using UV-visible absorption and X-ray diffraction analyses. These indicated that luteolin could bind with PPA, and that hydrogen bonds and van der Waals forces may be present. Overall, luteolin delayed starch digestion not only by binding with PPA but also by binding with starch. Thus, luteolin has the potential to prevent and control diabetes by being added into starch-based food to delay starch digestion.

Pharmaceutical Drugs and Natural Therapeutic Products for the Treatment of Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is the most widespread form of diabetes, characterized by chronic hyperglycaemia, insulin resistance, and inefficient insulin secretion and action. Primary care in T2DM is pharmacological, using drugs of several groups that include insulin sensitisers (e.g., biguanides, thiazolidinediones), insulin secretagogues (e.g., sulphonylureas, meglinides), alpha-glucosidase inhibitors, and the newest incretin-based therapies and sodium-glucose co-transporter 2 inhibitors. However, their long-term application can cause many harmful side effects, emphasising the importance of the using natural therapeutic products. Natural health substances including non-flavonoid polyphenols (e.g., resveratrol, curcumin, tannins, and lignans), flavonoids (e.g., anthocyanins, epigallocatechin gallate, quercetin, naringin, rutin, and kaempferol), plant fruits, vegetables and other products (e.g., garlic, green tea, blackcurrant, rowanberry, bilberry, strawberry, cornelian cherry, olive oil, sesame oil, and carrot) may be a safer alternative to primary pharmacological therapy. They are recommended as food supplements to prevent and/or ameliorate T2DM-related complications. In the advanced stage of T2DM, the combination therapy of synthetic agents and natural compounds with synergistic interactions makes the treatment more efficient. In this review, both pharmaceutical drugs and selected natural products, as well as combination therapies, are characterized. Mechanisms of their action and possible negative side effects are also provided.

The Aging Vasculature: Glucose Tolerance, Hypoglycemia and the Role of the Serum Response Factor

The fastest growing demographic in the U.S. at the present time is those aged 65 years and older. Accompanying advancing age are a myriad of physiological changes in which reserve capacity is diminished and homeostatic control attenuates. One facet of homeostatic control lost with advancing age is glucose tolerance. Nowhere is this more accentuated than in the high proportion of older Americans who are diabetic. Coupled with advancing age, diabetes predisposes affected subjects to the onset and progression of cardiovascular disease (CVD). In the treatment of type 2 diabetes, hypoglycemic episodes are a frequent clinical manifestation, which often result in more severe pathological outcomes compared to those observed in cases of insulin resistance, including premature appearance of biomarkers of senescence. Unfortunately, molecular mechanisms of hypoglycemia remain unclear and the subject of much debate. In this review, the molecular basis of the aging vasculature (endothelium) and how glycemic flux drives the appearance of cardiovascular lesions and injury are discussed. Further, we review the potential role of the serum response factor (SRF) in driving glycemic flux-related cellular signaling through its association with various proteins.

Design and synthesis of hydrazinecarbothioamide sulfones as potential antihyperglycemic agents

New hydrazinecarbothioamides with a phenylsulfonyl group were synthesized and their structures were identified by different spectroscopic data (¹ H NMR, ¹³ C NMR, two-dimensional NMR, mass spectrometry, elemental analysis, and single-crystal X-ray analysis). The mechanism describing the formation of the products was also discussed. The antidiabetic activity of the isolated products was investigated histochemically. The synthesized sulfonylalkylthiosemicarbazide exhibited antihyperglycemic activity in streptozotocin-induced diabetic mice. Compounds 5a and 5c significantly lowered the blood glucose level to 103.3 ± 1.8 and 102 ± 3.9 mg/dl, respectively. Also, they caused a significant decrease in malondialdehyde levels and normalized the glutathione levels in streptozotocin-induced diabetic mice, compared with the diabetic group. The results suggest that the synthesized hydrazinocarbothioamides may effectively inhibit the development of oxidative stress in diabetes.

Sulfonylureas may be useful for glycemic management in patients with diabetes and liver cirrhosis

This study aimed to investigate the long-term outcomes of sulfonylurea (SU) use in patients with T2DM and compensated liver cirrhosis. From January 1, 2000, to December 31, 2012, we selected the data of 3781 propensity-score-matched SU users and nonusers from Taiwan's National Health Insurance Research Database. The mean follow-up time for this study was 5.74 years. Cox proportional hazards models with robust sandwich standard error estimates were used to compare the risks of main outcomes between SU users and nonusers. The incidence of mortality during follow-up was 3.24 and 4.09 per 100 person-years for SU users and nonusers, respectively. The adjusted hazard ratios and 95% confidence intervals for all-cause mortality, major cardiovascular events, and decompensated cirrhosis in SU users relative to SU nonusers were 0.79 (0.71-0.88), 0.69 (0.61-0.80), and 0.82 (0.66-1.03), respectively. The SU-associated lower risks of death and cardiovascular events seemed to have a dose-response trend. This population-based cohort study demonstrated that SU use was associated with lower risks of death and major cardiovascular events compared with SU non-use in patients with T2DM and compensated liver cirrhosis. SUs may be useful for glycemic management for patients with liver cirrhosis.

Discovery of novel potent GPR40 agonists containing imidazo[1,2-a]pyridine core as antidiabetic agents

Free fatty acid receptor 1 (FFA1 or GPR40) has been studied for many years as a target for the treatment of type 2 diabetes mellitus. In order to increase potency and reduce hepatotoxicity, a series of novel compounds containing imidazo[1,2-a]pyridine scaffold as GPR40 agonist were synthesized. Compound I-14 was identified as an effective agonist as shown by the conspicuous drop in blood glucose in normal and diabetic mice. It had no risk of hepatotoxicity compared with TAK-875. Moreover, good pharmacokinetic (PK) properties of I-14 were observed (CL = 27.26 ml/h/kg, t_1/2 = 5.93 h). The results indicate that I-14 could serve as a possible candidate to treat diabetes.

New combination therapy of gliclazide and quercetin for protection against STZ-induced diabetic rats

AIMS

The use of natural agents with anti-diabetic effect in combination therapy adds further positive clinical implications in the management of diabetes mellitus. Interestingly, quercetin is one of the most potent naturally occurring antioxidant which possesses various pharmacological actions including anti-diabetic effect. Thus, this research was conducted to assess the efficiency of a new combination from gliclazide and quercetin on glycemic control as well as pancreatic islets and beta cells in STZ-experimental model of diabetes.

MAIN METHODS

Diabetes has been induced by a single intraperitoneal injection of streptozotocin (STZ; 45 mg/kg) in adult male Wistar rats. For 3 consecutive weeks, diabetic rats were given orally either gliclazide (10 mg/kg), quercetin (50 mg/kg), or their combination. At the end of the experiment, histological, immunohistochemical and morphometrical examination of pancreatic tissues was performed. Furthermore, the changes in glucose metabolism, lipid profile, oxidative and inflammatory status were evaluated.

KEY FINDINGS

Treatment with gliclazide alone decreased serum glucose, total cholesterol, triglycerides, malondialdehyde, tumor necrosis factor-alpha and nuclear factor kappa-Beta while increased serum C-peptide, superoxide dismutase, reduced glutathione and adiponectin levels. Combined administration of quercetin with gliclazide markedly augmented serum superoxide dismutase and reduced glutathione more than gliclazide alone and normalized all the above-mentioned parameters. Besides, this combination therapy restored immunostaining intensity, number of pancreatic islets and beta cells along with its area and perimeter.

SIGNIFICANCE

Based on the aforementioned results, this combination could be considered a promising one in diabetes mellitus management.

Mechanisms and Characteristics of Sulfonylureas and Glinides

BACKGROUND

Type 2 diabetes mellitus is a complex progressive endocrine disease characterized by hyperglycemia and life-threatening complications. It is the most common disorder of pancreatic cell function that causes insulin deficiency. Sulfonylurea is a class of oral hypoglycemic drugs. Over the past half century, these drugs, together with the subsequent non-sulfonylureas (glinides), have been the main oral drugs for insulin secretion.

OBJECTIVE

Through in-depth study, the medical profession considers it as an important drug for improving blood sugar control.

METHODS

The mechanism, characteristics, efficacy and side effects of sulfonylureas and glinides were reviewed in detail.

RESULTS

Sulfonylureas and glinides not only stimulated the release of insulin from pancreatic cells, but also had many extrapanular hypoglycemic effect, such as reducing the clearance rate of insulin in liver, reducing the secretion of glucagon, and enhancing the sensitivity of peripheral tissues to insulin in type 2 diabetes mellitus.

CONCLUSION

Sulfonylureas and glinides are effective first-line drugs for the treatment of diabetes mellitus. Although they have the risk of hypoglycemia, weight gain and cardiovascular disease, their clinical practicability and safety can be guaranteed as long as they are reasonably used.

An Insight of Alpha-amylase Inhibitors as a Valuable Tool in the Management of Type 2 Diabetes Mellitus

BACKGROUND

Among the millions of people around the world, the most prevalent metabolic disorder is diabetes mellitus. Due to the drawbacks which are associated with commercially available antidiabetic agents, new therapeutic approaches are needed to be considered. Alpha-amylase is a membrane- bound enzyme which is responsible for the breakdown of polysaccharides such as starch to monosaccharides which can be absorbed.

METHODS

We searched the scientific database using alpha-amylase, diabetes, antidiabetic agents as the keywords. Here in, only peer-reviewed research articles were collected which were useful to our current work.

RESULTS

To overcome the research gap, the alpha-amylase enzyme is regarded as a good target for antidiabetic agents to design the drug and provide an alternate approach for the treatment of type 2 diabetes mellitus. Basically, alpha-amylase inhibitors are classified into two groups: proteinaceous inhibitors, and non-proteinaceous inhibitors. Recently, non-proteinaceous inhibitors are being explored which includes chalcones, flavones, benzothiazoles, etc. as the potential antidiabetic agents.

CONCLUSION

Herein, we discuss various potential antidiabetic agents which are strategically targeted alpha-amylase enzyme. These are having lesser side effects as compared to other antidiabetic agents, and are proposed to prevent the digestion and absorption of glucose leading to a decrease in the blood glucose level.

G-protein-coupled receptor 40 agonist GW9508 potentiates glucose-stimulated insulin secretion through activation of protein kinase Cα and ε in INS-1 cells

OBJECTIVE

The mechanism by which G-protein-coupled receptor 40 (GPR40) signaling amplifies glucose-stimulated insulin secretion through activation of protein kinase C (PKC) is unknown. We examined whether a GPR40 agonist, GW9508, could stimulate conventional and novel isoforms of PKC at two glucose concentrations (3 mM and 20 mM) in INS-1D cells.

METHODS

Using epifluorescence microscopy, we monitored relative changes in the cytosolic fluorescence intensity of Fura2 as a marker of change in intracellular Ca2+ ([Ca2+]i) and relative increases in green fluorescent protein (GFP)-tagged myristoylated alanine-rich C kinase substrate (MARCKS-GFP) as a marker of PKC activation in response to GW9508 at 3 mM and 20 mM glucose. To assess the activation of the two PKC isoforms, relative increases in membrane fluorescence intensity of PKCα-GFP and PKCε-GFP were measured by total internal reflection fluorescence microscopy. Specific inhibitors of each PKC isotype were constructed and synthesized as peptide fusions with the third α-helix of the homeodomain of Antennapedia.

RESULTS

At 3 mM glucose, GW9508 induced sustained MARCKS-GFP translocation to the cytosol, irrespective of changes in [Ca2+]i. At 20 mM glucose, GW9508 induced sustained MARCKS-GFP translocation but also transient translocation that followed sharp increases in [Ca2+]i. Although PKCα translocation was rarely observed, PKCε translocation to the plasma membrane was sustained by GW9508 at 3 mM glucose. At 20 mM glucose, GW9508 induced transient translocation of PKCα and sustained translocation as well as transient translocation of PKCε. While the inhibitors (75 μM) of each PKC isotype reduced GW9508-potentiated, glucose-stimulated insulin secretion in INS-1D cells, the PKCε inhibitor had a more potent effect.

CONCLUSION

GW9508 activated PKCε but not PKCα at a substimulatory concentration of glucose. Both PKC isotypes were activated at a stimulatory concentration of glucose and contributed to glucose-stimulated insulin secretion in insulin-producing cells.

Development of a Novel Series of Anticancer and Antidiabetic: Spirothiazolidines Analogs

4-(4-Aminophenyl)-1-thia-4-azaspiro[4.5]decan-3-one 1 was prepared and allowed to react with nitrogen nucleophiles to give the corresponding hydrazones 2–4. Further, compound 1 underwent diazotization and afforded the parallel hydrazono derivative 5; moreover, compound 1 refluxed with active methylene derivatives yielded the corresponding aminospirothiazolo pyridine–carbonitrile derivative 6 and spirothiazolopyridinone–carbonitrile derivative 7. Condensation of spirothiazolidine 1 with 4-chlorobenzaldehyde gave the corresponding spiro arylidiene derivative 8, which was utilized as a component of Micheal addition to react with excess of nitrogen nucleophiles to yield novel ring frameworks 4-(3′-(4-chlorophenyl)–spiro [cyclohexane-1,5′-pyrazolo[3,4-d]thiazol]-6′(1′H)-yl)aniline (9) and 4-(3′-(4-chlorophenyl)-6′H- spiro[cyclohexane-1,5′-thiazolo[5,4-d]isoxazol]-6′-yl)aniline (10). Finally, when spirothiazolo pyridinone–carbonitrile derivative 7 sodium salt generated in situ was reacted with different alkyl halides, it produced the corresponding N-derivatives 12–16. Three compounds, 6, 14, and 16, showed high significantly anticancer activities compared with Doxorubicin® (positive control) against human breast carcinoma (MCF-7) and human liver carcinoma (HepG-2) cell lines. On the other hand, compounds 6 and 9 showed higher therapeutic indices for both of alpha-amylase inhibitor and alpha-glucosidase inhibitor than the other tested compounds compared with the antidiabetic Acarbose (positive control).

Attitude and safety of patients with diabetes observing the Ramadan fast

AIMS

To describe the attitude of type 2 diabetes patients toward Ramadan fasting. A Secondary purpose was to describe rates of hypoglycemia during Ramadan according to type of treatment.

METHODS

A prospective, non-randomized study for 2 years. Participants with type 2 diabetes attending Dammam Diabetes Center, Saudi Arabia were stratified for fasting according to ADA recommendations. Results are presented using mean, standard deviation and percentages.

RESULTS

Total of 360 participants with type 2 diabetes. Mean ± SD glycosylated hemoglobin was 8.9 ± 2.1. More than 80% of individuals were in the ADA higher risk group however, they all fasted Ramadan. The mean non-fasting days was 2.6 days and overall rate of hypoglycaemia was 24.7%. Both parameters were directly proportionate to the risk stratification level (P-value <0.05). Despite hypoglycaemia, 29.3% continued fasting. Hypoglycemia was highest in patients treated with insulin (P-value <0.05) followed by those treated with oral agents including sulphonylurea as compared to oral agents excluding sulfonylurea (P-value = 0.002). Those who experienced hypoglycemia prior to Ramadan had the highest rate of hypoglycemia during Ramadan (53.3%) (P-value = 0.0065).

CONCLUSIONS

Despite medical advice, the vast majority of type 2 diabetes participants categorized as high risk, fasted Ramadan. Approximately one quarter of people with type 2 diabetes in our cohort experience hypoglycaemia and this was directly related to their fasting risk level. A sizeable proportion continued the fast despite hypoglycemic. Insulin therapy with or without oral agents and previous episodes of hypoglycemia before Ramadan predicted hypoglycemia risk during Ramadan. HbA1c and weight showed some clinical improvements post Ramadan fasting. This is a single center study of mostly high risk fasting patients and hence, these results should not be generalized.

A potent free fatty acid receptor 1 agonist with a glucose-dependent antihyperglycemic effect

PAFA is a promising free fatty acid receptor 1 agonist with a glucose-dependent antihyperglycemic effect, allowing for treating type-2 diabetes.

Olive leaves extract attenuates type II diabetes mellitus-induced testicular damage in rats: Molecular and biochemical study

Diabetes mellitus (DM) has emerged as a public healthcare problem. Sustained hyperglycemia has been linked with many complications including impaired male fertility Olive tree (Olea europaea L.) leaves have been extensively used in traditional remedies worldwide to control blood glucose level in DM. In this study, the beneficial role of olive leaves extract (OLE) was investigated to combat diabetes-induced adverse effect on testicular tissues. Thirty male Wistar rats were divided into 5 equal groups: normal control group, streptozotocin (STZ)-diabetic group and diabetic groups which were given glibenclamide (GLB) or OLE at 250 and 500 mg/kg for 9 weeks to investigate the efficiency of olive leaves extract (OLE) in reducing the deleterious effect of diabetes on the reproductive system of male rats. Rats were checked for serum glucose, insulin, testosterone and gonadotropins. Also, testicular antioxidants, epididymal sperm characteristics and testicular histopathology were assessed. Expression of the testicular steroidogenic enzymes, cholesterol side-chain cleavage enzyme (P450 scc) and 17β-hydroxysteroid dehydrogenase (17β-HSD) was examined. Moreover, androgen receptor and proliferating cell nuclear antigen (PCNA) protein immunohistochemistry were assessed in testes. STZ-induced diabetes significantly increased serum glucose. However, STZ significantly decreased serum levels of insulin, testosterone, follicle stimulating hormone (FSH) and luteinizing hormone (LH). Marked reductions in testicular antioxidants with elevated malondialdehyde (MDA) parallel with deterioration of the testicular histoarchitecture and epididymal sperm characteristics were recorded. Administration of GLB or OLE (250 and 500 mg/kg) resulted in a significant recovery of the above mentioned parameters in STZ-diabetic rats. Interestingly, OLE shows greater glycemic improvement and testicular protection than GLB with the highest percentage protection exhibited by the OLE high dose. Furthermore, OLE significantly induced testicular steroidogenesis in diabetic rat as evidenced by elevated P450 scc and 17β-HSD mRNA expression. The study proves that OLE possesses a potential protective role against diabetes-induced reproductive disorders, which may be due to its antioxidant activity and its ability to normalize testicular steroidogenesis.

Analysis of the characteristics of patients with diabetes mellitus who attend a tertiary hospital emergency department for a hypoglycemic event

INTRODUCTION AND OBJECTIVE

Hypoglycemia associated to insulin or other glucose-lowering agents is one of the most common causes of visits to the emergency department for adverse drug reactions. The study objective was to analyze the characteristics of patients with diabetes mellitus (DM) who attend a tertiary hospital emergency department for a hypoglycemic event.

PATIENTS AND METHODS

A 3-year retrospective analysis was conducted of patients with DM who attended the emergency department of Hospital Universitari de Bellvitge for a hypoglycemic event. An analysis was made of epidemiological and diabetes-related characteristics, prevalence of chronic diabetic complications and other comorbidities, the glucose-lowering treatment and the result of the hypoglycemic episode.

RESULTS

Of the 149 hypoglycemic events analyzed, 81.9% occurred in patients with type 2 DM. Mean age of patients with type 2 DM was 75.4 years. DM duration was longer than 10 years in 69.4% of patients. The prevalence rates of chronic kidney disease and cognitive decline were 38.5% and 19.7% respectively in patients with type 2 DM. Insulin with or without other concomitant glucose-lowering agents was associated to 78.7% of episodes in type 2 DM patients. The remaining 21.3% were associated to oral hypoglycemic agents, mainly glibenclamide. After the event, 13.4% of patients required hospital admission, and in 36.8% of these hypoglycemia was associated to use of glibenclamide.

CONCLUSIONS

A majority of hypoglycemic events occurred in elderly patients with type 2 DM, with a high prevalence of associated comorbidities and treated with insulin and sulfonylureas, particularly glibenclamide.

Cytochrome P450: Polymorphisms and Roles in Cancer, Diabetes and Atherosclerosis

Cytochromes P450s (CYPs) constitute a superfamily of enzymes that catalyze the metabolism of drugs and other substances. Endogenous substrates of CYPs include eicosanoids, estradiol, arachidonic acids, cholesterol, vitamin D and neurotransmitters. Exogenous substrates of CYPs include the polycyclic aromatic hydrocarbons and about 80% of currently used drugs. Some isoforms can activate procarcinogens to ultimate carcinogens. Genetic polymorphisms of CYPs may affect the enzyme catalytic activity and have been reported among different populations to be associated with various diseases and adverse drug reactions. With regard of drug metabolism, phenotypes for CYP polymorphism range from ultrarapid to poor metabolizers. In this review, we discuss some of the most clinically important CYPs isoforms (CYP2D6, CYP2A6, CYP2C19, CYP2C9, CYP1B1 and CYP1A2) with respect to gene polymorphisms and drug metabolism. Moreover, we review the role of CYPs in renal, lung, breast and prostate cancers and also discuss their significance for atherosclerosis and type 2 diabetes mellitus.

Managing feline diabetes: current perspectives

Diabetes mellitus is a common endocrine disease in cats. While type 2 diabetes is the most common form seen in cats, other underlying causes may contribute to insulin resistance. Guidelines for diagnosis vary and often do not take into account prediabetic cats. The goals of treatment are to maximize the chance of remission, while minimizing the risks of hypoglycemia. This article presents a further overview of current treatment and monitoring recommendations for diabetic cats.

Current anti-diabetic agents and their molecular targets: A review

Diabetes mellitus is a medical condition characterized by the body's loss of control over blood sugar. The frequency of diagnosed cases and consequential increases in medical costs makes it a rapidly growing chronic disease that threatens human health worldwide. In addition, its unnerving statistical projections are perilous to both the economy of the nation and man's life expectancy. Type-I and type-II diabetes are the two clinical forms of diabetes mellitus. Type-II diabetes mellitus (T2DM) is illustrated by the abnormality of glucose homeostasis in the body, resulting in hyperglycemia. Although significant research attention has been devoted to the development of diabetes regimens, which demonstrates success in lowering blood glucose levels, their efficacies are unsustainable due to undesirable side effects such as weight gain and hypoglycemia. Over the years, heterocyclic scaffolds have been the basis of anti-diabetic chemotherapies; hence, in this review we consolidate the use of bioactive scaffolds, which have been evaluated for their biological response as inhibitors against their respective anti-diabetic molecular targets over the past five years (2012-2017). Our investigation reveals a diverse target set which includes; protein tyrosine phosphatase 1 B (PTP1B), dipeptidly peptidase-4 (DPP-4), free fatty acid receptors 1 (FFAR1), G protein-coupled receptors (GPCR), peroxisome proliferator activated receptor-γ (PPARγ), sodium glucose co-transporter-2 (SGLT2), α-glucosidase, aldose reductase, glycogen phosphorylase (GP), fructose-1,6-bisphosphatase (FBPase), glucagon receptor (GCGr) and phosphoenolpyruvate carboxykinase (PEPCK). This review offers a medium on which future drug design and development toward diabetes management may be modelled (i.e. optimization via structural derivatization), as many of the drug candidates highlighted show promise as an effective anti-diabetic chemotherapy.

Design, synthesis and structure-activity relationship studies of GPR40 agonists containing amide linker

Free fatty acid receptor 1 (FFAR1/GPR40) attracted significant attention as a potential target for developing novel antidiabetic drugs because of its unique mechanism in glucose homeostasis. Several reports have expressed concerns about central nervous system (CNS) penetration of GPR40 agonists, which is possibly attributed to their high lipophilicity and low total polar surface area. Herein, we report our efforts to improve the physicochemical properties and pharmacokinetic profiles of LY2881835, a GPR40 agonist that had undergone Phase I clinical trial, through a series of structural optimizations. We identified an orally efficacious compound, 15k, which possessed increased plasma exposure, prolonged half-life and reduced CNS exposure and liver to plasma distribution ratio compared with LY2881835. 15k is a potentially valuable lead compound in the development of safe and efficacious GPR40-targeted drugs to treat type 2 diabetes mellitus.

Pharmacokinetics and safety of oral glyburide in dogs with acute spinal cord injury

Background

Glyburide (also known as glibenclamide) is effective in reducing the severity of tissue destruction and improving functional outcome after experimental spinal cord injury in rodents and so has promise as a therapy in humans. There are many important differences between spinal cord injury in experimental animals and in human clinical cases, making it difficult to introduce new therapies into clinical practice. Spinal cord injury is also common in pet dogs and requires new effective therapies, meaning that they can act as a translational model for the human condition while also deriving direct benefits from such research. In this study we investigated the pharmacokinetics and safety of glyburide in dogs with clinical spinal cord injury.

Methods

We recruited dogs that had incurred an acute thoracolumbar spinal cord injury within the previous 72 h. These had become acutely non-ambulatory on the pelvic limbs and were admitted to our veterinary hospitals to undergo anesthesia, cross sectional diagnostic imaging, and surgical decompression. Oral glyburide was given to each dog at a dose of 75 mcg/kg. In five dogs, we measured blood glucose concentrations for 10 h after a single oral dose. In six dogs, we measured serum glyburide and glucose concentrations for 24 h and estimated pharmacokinetic parameters to estimate a suitable dose for use in a subsequent clinical trial in similarly affected dogs.

Results

No detrimental effects of glyburide administration were detected in any participating dog. Peak serum concentrations of glyburide were attained at a mean of 13 h after dosing, and mean apparent elimination half-life was approximately 7 h. Observed mean maximum plasma concentration was 31 ng/mL. At the glyburide dose administered there was no observable association between glyburide and glucose concentrations in blood.

Discussion

Our data suggest that glyburide can be safely administered to dogs that are undergoing anesthesia, imaging and surgery for treatment of their acute spinal cord injury and can attain clinically-relevant serum concentrations without developing hazardous hypoglycemia. Serum glyburide concentrations achieved in this study suggest that a loading dose of 150 mcg/kg followed by repeat doses of 75 mcg/kg at 8-hourly intervals would lead to serum glyburide concentrations of 25-50 ng/mL within an acceptably short enough period after oral administration to be appropriate for a clinical trial in canine spinal cord injury.

Diabetes Mellitus Secondary to Cushing's Disease

Associated with important comorbidities that significantly reduce patients' overall wellbeing and life expectancy, Cushing's disease (CD) is the most common cause of endogenous hypercortisolism. Glucocorticoid excess can lead to diabetes, and although its prevalence is probably underestimated, up to 50% of patients with CD have varying degrees of altered glucose metabolism. Fasting glycemia may nevertheless be normal in some patients in whom glucocorticoid excess leads primarily to higher postprandial glucose levels. An oral glucose tolerance test should thus be performed in all CD patients to identify glucose metabolism abnormalities. Since diabetes mellitus (DM) is a consequence of cortisol excess, treating CD also serves to alleviate impaired glucose metabolism. Although transsphenoidal pituitary surgery remains the first-line treatment for CD, it is not always effective and other treatment strategies may be necessary. This work examines the main features of DM secondary to CD and focuses on antidiabetic drugs and how cortisol-lowering medication affects glucose metabolism.

Syntheses of Novel 4-Substituted N-(5-amino-1H-1,2,4-triazol-3-yl)pyridine-3-sulfonamide Derivatives with Potential Antifungal Activity

Candidiasis represent a serious threat for patients with altered immune responses. Therefore, we have undertaken the synthesis of compounds comprising a pyridine-3-sulfonamide scaffold and known antifungally active 1,2,4-triazole substituents. Thus a series of novel 4-substituted N-(5-amino-1H-1,2,4-triazol-3-yl)pyridine-3-sulfonamides have been synthesized by multistep reactions starting from 4-chloropyridine-3-sulfonamide via N′-cyano-N-[(4-substitutedpyridin-3-yl)sulfonyl]carbamimidothioates which were further converted with hydrazine hydrate to the corresponding 1,2,4-triazole derivatives 26–36. The final compounds were evaluated for antifungal activity against strains of the genera Candida, Geotrichum, Rhodotorula, and Saccharomycess isolated from patients with mycosis. Many of them show greater efficacy than fluconazole, mostly towards Candida albicans and Rhodotorula mucilaginosa species, with MIC values ≤ 25 µg/mL. A docking study of the most active compounds 26, 34 and 35 was performed showing the potential mode of binding to Candida albicans lanosterol 14α-demethylase. Also in vitro cytotoxicity of selected compounds have been evaluated on the NCI-60 cell line panel.

Optical control of GPR40 signalling in pancreatic β-cells

Fatty acids activate GPR40 and K+ channels to modulate β-cell function. Herein, we describe the design and synthesis of FAAzo-10, a light-controllable GPR40 agonist based on Gw-9508. FAAzo-10 is a potent GPR40 agonist in the trans-configuration and can be inactivated on isomerization to cis with UV-A light. Irradiation with blue light reverses this effect, allowing FAAzo-10 activity to be cycled ON and OFF with a high degree of spatiotemporal precision. In dissociated primary mouse β-cells, FAAzo-10 also inactivates voltage-activated and ATP-sensitive K+ channels, and allows us to control glucose-stimulated Ca2+ oscillations in whole islets with light. As such, FAAzo-10 is a useful tool to study the complex effects, with high specificity, which FA-derivatives such as Gw-9508 exert at multiple targets in mouse β-cells.

Interventions to improve β-cell mass and function

Diabetes mellitus (T2DM) has become an epidemiologically important disease worldwide and is also becoming a great matter of concern due to the effects associated with it like: high morbidity, elevated health care cost and shortened life span. T2DM is a chronic metabolic disease characterized by insulin resistance as well as β-cell dysfunction. It is widely accepted that in the face of insulin resistance, euglycemia can be maintained by increase in pancreatic β-cell mass and insulin secretion. This compensation is largely due to enhanced secretion of insulin by the β-cell mass, which is present initially, and thereby subsequent increases in β-cell mass provide additional insulin secretion. However, the mechanism by which β-cell anatomical plasticity and functional plasticity for insulin secretion is coordinated and executed in different physiological and pathophysiological states is complex and has been poorly understood. As the incidence of T2DM continues to increase at an alarming rate, it is becoming imperative to shift the research focus towards the β-cell physiology where identification of novel pathways that influence the β-cell proliferation and/or contribute to increase insulin secretion has the potential to lead to new therapies for preventing or delaying onset of disease.

Cardiovascular Protection in the Treatment of Type 2 Diabetes: A Review of Clinical Trial Results Across Drug Classes

Patients with type 2 diabetes (T2DM) have a significantly higher risk of developing cardiovascular disease (CVD)-namely myocardial infarction, heart failure, and stroke. Despite clear advances in the prevention and treatment of CVD, the impact of T2DM on CVD outcome remains high and continues to escalate. Available evidence indicates that the risk of macrovascular complications increases with the severity of hyperglycemia, thus suggesting that the relation between metabolic disturbances and vascular damage is approximately linear. Although current antidiabetic drugs are highly effective for the management of hyperglycemia, most T2DM patients remain exposed to a substantial and concrete risk of CVD. Over the last decade many glucose-lowering agents have been tested for their safety and efficacy in T2DM with CVD. Noteworthy, most of these studies failed to show a significant benefit in terms of CV morbidity and mortality, despite intensive glycemic control. The recent trials Empagliflozin Cardiovascular Outcome Event Trial in Type 2 Diabetes Mellitus Patients-Removing Excess Glucose (EMPA-REG OUTCOME); Trial to Evaluate Cardiovascular and Other Long-term Outcomes with Semaglutide in Subjects with Type 2 Diabetes (SUSTAIN-6); Liraglutide Effect and Action in Diabetes: Evaluation of Cardiovascular Outcome Results (LEADER); and Insulin Resistance Intervention After Stroke (IRIS) have shed some light on this important clinical issue, thus showing a convincing effect of empagliflozin, liraglutide, and pioglitazone on CVD outcomes. Here we provide a critical and updated overview of the main glucose-lowering agents and their risk/benefit ratio for the prevention of CVD in patients with T2DM.

Metabolomic analysis of healthy human urine following administration of glimepiride using a liquid chromatography-tandem mass spectrometry

Glimepiride, a third generation sulfonylurea, is an antihyperglycemic agent widely used to treat type 2 diabetes mellitus. In this study, an untargeted urinary metabolomic analysis was performed to identify endogenous metabolites affected by glimepiride administration. Urine samples of twelve healthy male volunteers were collected before and after administration of 2 mg glimepiride. These samples were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and then subjected to multivariate data analysis including principal component analysis and orthogonal partial least squares discriminant analysis. Through this metabolomic profiling, we identified several endogenous metabolites such as adenosine 3', 5'-cyclic monophosphate (cAMP), quercetin, tyramine, and urocanic acid, which exhibit significant metabolomic changes between pre- and posturine samples. Among these, cAMP, which is known to be related to insulin secretion, was the most significantly altered metabolite following glimepiride administration. In addition, the pathway analysis showed that purine, tyrosine, and histidine metabolism was affected by pharmacological responses to glimepiride. Together, the results suggest that the pharmacometabolomic approach, based on LC-MS/MS, is useful in understanding the alterations in biochemical pathways associated with glimepiride action.

Cardiovascular Protection in the Treatment of Type 2 Diabetes: A Review of Clinical Trial Results Across Drug Classes

Patients with type 2 diabetes (T2DM) have a significantly higher risk of developing cardiovascular disease (CVD)-namely myocardial infarction, heart failure, and stroke. Despite clear advances in the prevention and treatment of CVD, the impact of T2DM on CVD outcome remains high and continues to escalate. Available evidence indicates that the risk of macrovascular complications increases with the severity of hyperglycemia, thus suggesting that the relation between metabolic disturbances and vascular damage is approximately linear. Although current antidiabetic drugs are highly effective for the management of hyperglycemia, most T2DM patients remain exposed to a substantial and concrete risk of CVD. Over the last decade many glucose-lowering agents have been tested for their safety and efficacy in T2DM with CVD. Noteworthy, most of these studies failed to show a significant benefit in terms of CV morbidity and mortality, despite intensive glycemic control. The recent trials Empagliflozin Cardiovascular Outcome Event Trial in Type 2 Diabetes Mellitus Patients-Removing Excess Glucose (EMPA-REG OUTCOME); Trial to Evaluate Cardiovascular and Other Long-term Outcomes with Semaglutide in Subjects with Type 2 Diabetes (SUSTAIN-6); Liraglutide Effect and Action in Diabetes: Evaluation of Cardiovascular Outcome Results (LEADER); and Insulin Resistance Intervention After Stroke (IRIS) have shed some light on this important clinical issue, thus showing a convincing effect of empagliflozin, liraglutide, and pioglitazone on CVD outcomes. Here we provide a critical and updated overview of the main glucose-lowering agents and their risk/benefit ratio for the prevention of CVD in patients with T2DM.

Gliclazide

Gliclazide is a second-generation oral hypoglycemic drug used for the treatment of noninsulin-dependent diabetes mellitus. It belongs to the sulfonylurea class that stimulates insulin secretion from pancreatic β-cells by inhibiting ATP-dependent potassium channels. Gliclazide also possesses unique antioxidant properties and other beneficial hemobiological effects. This profile represents a comprehensive description of the physical properties, chemical synthesis, spectroscopic characterization (FTIR, ¹H NMR, ¹³C NMR, UV, and single-crystal X-ray), methods of analysis, pharmacological actions, and pharmacokinetic and pharmacodynamic properties of the title drug.

The role of various peroxisome proliferator-activated receptors and their ligands in clinical practice

Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors involved in several physiological processes including modulation of cellular differentiation, development, metabolism of carbohydrates, lipids, proteins, and tumorigenesis. The aim of this review is to examine how different PPAR ligands act, and discuss their use in clinical practice. PPAR ligands have a lot of effects and applications in clinical practice. Some PPAR ligands such as fibrates (PPAR-α ligands) are currently used for the treatment of dyslipidemia, while pioglitazone and rosiglitazone (PPAR-γ ligands) are anti-diabetic and insulin-sensitizing agents. Regarding new generation drugs, acting on both α/γ, β/δ, or α/δ receptors simultaneously, preliminary data on PPAR-α/γ dual agonists revealed a positive effect on lipid profile, blood pressure, atherosclerosis, inflammation, and anti-coagulant effects, while the overexpression of PPAR-β/δ seems to prevent obesity and to decrease lipid storage in cardiac cells. Finally, PPAR-α/δ dual agonist induces resolution of nonalcoholic steatohepatitis without fibrosis worsening.

Synthesis of substituted 2H-benzo[e]indazole-9-carboxylate as a potent antihyperglycemic agent that may act through IRS-1, Akt and GSK-3β pathways

Based on high throughput screening of our chemical library, we identified two 4,5-dihydro-2H-benzo[e]indazole derivatives (5d and 5g), which displayed a significant effect on glucose uptake in L6 skeletal muscle cells. Based on these lead molecules, a series of benzo[e]indazole derivatives were prepared. Among all the synthesized dihydro-2H-benzo[e]indazoles, 8-(methylthio)-2-phenyl-6-p-tolyl-4,5-dihydro-2H-benzo[e]indazole-9-carboxylate (5e) showed significant glucose uptake stimulation in L6 skeletal muscle cells, even better than lead compounds. Additionally, 5e decreased glucagon-induced glucose release in HepG2 hepatoma cells. The 2H-benzo[e]indazole 5e exerted an antihyperglycemic effect in normal, sucrose challenged streptozotocin-induced diabetic rats and type 2 diabetic db/db mice. Treatment with 5e at a dose of 30 mg kg-1 in db/db mice caused a significant decrease in triglyceride and total cholesterol levels and increased the HDL-C level in a significant manner. The mechanistic studies revealed that the 2H-benzo[e]indazole 5e significantly stimulated insulin-induced signaling at the level of IRS-1, Akt and GSK-3β in L6 skeletal muscle cells, possibly by inhibiting protein tyrosine phosphatase-1B. This new 2H-benzo[e]indazole derivative has potential for the treatment of diabetes with improved lipid profile.

Sulfonylurea Poisoning in a Healthy Toddler

Ingestion of sulfonylureas is life-threatening in toddlers and children due to its strong and prolonged hypoglycemic effect. The authors present a 15-mo-old boy with accidental ingestion of Glipizide who presented with encephalopathy, seizure and severe hypoglycemia. The management included parenteral dextrose and octreotide administration to maintain euglycemia, followed by complete neurological recovery within 24 h. Sulphonylurea intoxication should be considered in previously healthy toddlers and children presenting with hypoglycemia especially if any caregiver is on sulfonylurea drugs.

Glibenclamide Prevents Diabetes in NOD Mice

Previous work has revealed that Cx36, the sole connexin expressed in the insulin-producing beta cells, enhances the secretion of insulin, and promotes the resistance of beta cells against pro-inflammatory cytokines. In parallel, the anti-diabetic sulphonylurea glibenclamide was shown to promote the assembly and function of Cx36 channels. Here, we assessed whether glibenclamide could protect the insulin-producing cells against conditions mimicking those expected at the onset of type 1 diabetes. We found that the drug 1) protected in vitro the mouse MIN6 cells from the apoptosis and loss of Cx36, which are induced by Th1 cytokines; 2) prevented the development of hyperglycemia as well as the loss of beta cells and Cx36, which rapidly develop with aging in untreated NOD mice; 3) modified the proportion of effector CD4⁺ and CD8⁺ T cells in pancreatic draining lymph nodes. The data imply that an early glibenclamide treatment may help protecting beta cells against the autoimmune attack, which triggers the development of type 1 diabetes.