Impaired β cell function in Chinese newly diagnosed type 2 diabetes mellitus with hyperlipidemia

Short-Chain Fatty-Acid-Producing Micro-Organisms Regulate the Pancreatic FFA2-Akt/PI3K Signaling Pathway in a Diabetic Rat Model Affected by Pumpkin Oligosaccharides

Herein, we applied the Illumina MiSeq pyrosequencing platform to amplify the V3-V4 hypervariable regions of the 16 S rRNA gene of the gut microbiota (GM) and a gas chromatograph-mass spectrometer to detect the metabolites after supplementation with pumpkin oligosaccharides (POSs) to determine the metabolic markers and mechanisms in rats with type 2 diabetes (T2D). The POSs alleviated glucolipid metabolism by decreasing the serum low-density lipoprotein (LDL), total cholesterol (TC), and glucose levels. These responses were supported by a shift in the gut microbiota, especially in the butyric-acid-producing communities. Meanwhile, elevated total short-chain fatty acid (SCFA), isovaleric acid, and butyric acid levels were observed after supplementation with POSs. Additionally, this work demonstrated that supplementation with POSs could reduce TNF-α and IL-6 secretion via the FFA2-Akt/PI3K pathway in the pancreas. These results suggested that POSs alleviated T2D by changing the SCFA-producing gut microbiota and SCFA receptor pathways.

Antioxidant Potential and Improvement Activities of Sterculia setigera Delile on Insulin Resistance in Type 2 Diabetic Rats Induced by High-Fat Diet and Low Dose of Streptozotocin

Background

S. setigera is widely used in traditional medicine throughout the world. Ethnobotanical surveys have revealed its use to handle diabetes. This present research investigated the antioxidant potential and improvement activities of S. setigera Delile on insulin resistance in type 2 diabetic rats.

Methods

Male rats fed high-fat diet for 6 weeks followed by a single-dose intraperitoneal injection of streptozotocin (35 mg/kg) induced hyperglycemia. 72 hours after injection of streptozotocin, diabetic rats received treatment for 21 days. Fasting blood glucose was measured. Serum biochemical and hepatic biomarkers were evaluated. A hepatic histological study was performed. Oxidative stress biomarkers were assessed in liver.

Results

Doses of 200 and 400 mg/kg reduced the blood glucose with the reduction index of 53.75 and 62.1%, respectively. There was also good improvement in lipid profile and insulin. The dose of 400 mg/kg better reduced subcutaneous fat mass with a difference in reduction index (1.5 to 5.8%). The extract resulted in a decrease in malondialdehyde levels and an increase in catalase activities. The extract showed significant inhibitory potential towards α-amylase 18.78% to 55.91% and α-glucosidase 23.91% to 67.76%.

Conclusion

S. setigera extract could thus reverse insulin resistance and oxidative stress in type 2 diabetic rats induced.

Resveratrol Mitigates Diabetic Testicular Dysfunction, Endocrine Deficits, and Insulin Resistance via Suppression of Sperm-Endocrine Aberrations and Oxidative Inflammation in Rats

Diabetes mellitus (DM) provokes reproductive impairments through endocrine disturbance, sperm deficits, and testicular oxidative inflammation. The study investigated the reproductive protective effects of resveratrol (RSV) against testicular oxidative inflammation, sperm/endocrine deficits, and insulin resistance in streptozotocin- (STZ-, 65 mg/kg) induced DM rat model. Male rats were randomly divided into 4 groups ( $n=6$ ): control, DM, RSV (150 mg/kg bw, orally), and RSV+DM group (21 days). The nontreated DM rats showed marked decreases in serum insulin, reproductive hormones (T, LH, and FSH), and lipid profile levels compared to control. The homeostatic index of insulin resistance (HOMA-IR) and the quantitative insulin sensitivity check index (QUICKI) were adversely modulated. Sperm count and motility were profoundly decreased, whereas sperm abnormality was significantly increased. The testicular activities of catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD), and malondialdehyde (MDA) level, along with inflammatory cytokines (TNF-α, IL-6, IL-4, and IL-10) were significantly dysregulated. The DM induced histopathological lesions compared to control rats. Interestingly, the RSV administration to DM rats attenuated the altered reproductive parameters, restored antioxidant mechanism, and anti-inflammatory responses with improved insulin resistance. RSV could prevent DM-induced reproductive deficits and insulin resistance via modulating oxidative stress-mediated testicular inflammation in rats.

Evaluation of Antidiabetic Properties of the Leaves Extract of Ficus vallis-choudae Delile in a Model of Type 2 Diabetes Induced by High-Fat Diet and Streptozotocin

This work aimed to determine the phytochemical composition of the aqueous extract of leaves of Ficus vallis-choudae (AEFV) and to evaluate its antidiabetic properties on a model of type 2 diabetes induced by a high-fat diet (HFD) and a low dose of streptozotocin (STZ). The phytochemical analysis was carried out according to several methods using the standard of each bioactive compound. Type 2 diabetes was induced by feeding rats for 4 weeks with HFD lard followed by injection of a low dose of STZ (35 mg/kg). After induction, the rats were divided into groups and treated for 28 days with metformin (40 mg/kg) and the AEFV at doses of 110, 220, and 440 mg/kg. The results showed that the AEFV contains saponins, flavonoids, tannins, and total polyphenols. In addition, it dramatically reduced body mass, body mass index (BMI), atherogenic index (AI), coronary heart risk index (CRI), and abdominal fat and increased homeostatic model assessment of β-cell function (HOMA-β), high-density lipoprotein cholesterol (HDL-c) levels, and cardioprotective index (CI). The AEFV also lowered blood glucose levels, insulinemia, homeostatic model assessment of insulin resistance (HOMA-IR) index, and total cholesterol (TC), triglycerides (TG), low-density lipoproteins cholesterol (LDL-c), and very-low-density lipoproteins cholesterol (VLDL-c) levels. There was a decrease in alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activity and in urea and serum creatinine levels following the administration of AEFV. The AEFV caused increased superoxide dismutase (SOD) and catalase (CAT) activities, reduced glutathione (GSH) levels, and decreased malondialdehyde (MDA) levels in the liver, kidneys, and heart of rats. The AEFV has hypoglycemic, antioxidant, and cardioprotective properties, thus validating its use in traditional medicine for the treatment of type 2 diabetes and its complications.

Disturbed Lipid Metabolism in Diabetic Patients with Manifest Coronary Artery Disease Is Associated with Enhanced Inflammation

Background: Diabetic vasculopathy plays an important role in the pathophysiology of coronary artery disease (CAD) with oxidative stress as a strong mediator. This study aims to elucidate the underlying pathomechanisms of diabetic cardiac vasculopathy leading to coronary disease with an emphasis on the role of oxidative stress. Therefore, novel insights into antioxidant pathways might contribute to new strategies in the treatment and prevention of diabetic CAD. Methods: In 20 patients with insulin-dependent or non-insulin dependent diabetes mellitus (IDDM/NIDDM) and 39 non-diabetic (CTR) patients, myocardial markers of oxidative stress, vasoactive proteins, endothelial nitric oxide synthase (eNOS), activated phosphorylated eNOS (p-eNOS), and antioxidant enzymes, e.g., tetrahydrobiopterin generating dihydrofolate reductase (DHFR), heme oxygenase (HO-1), as well as serum markers of inflammation, e.g., E-selectin, interleukin-6 (IL-6), and lipid metabolism, e.g., high- and low-density lipoptrotein (HDL- and LDL-cholesterol) were determined in specimens of right atrial tissue and in blood samples from type 2 diabetic and non-diabetic patients undergoing coronary artery bypass graft (CABG) surgery. Results: IDDM/NIDDM increased markers of inflammation (e.g., E-selectin, p = 0.005 and IL-6, p = 0.051), decreased the phosphorylated myocardial p-eNOS (p = 0.032), upregulated the myocardial stress response protein HO-1 (p = 0.018), and enhanced the serum LDL-/HDL-cholesterol ratio (p = 0.019). However, the oxidative stress markers in the myocardium and the expression of vasoactive proteins (eNOS, DHFR) showed only marginal adverse changes in patients with IDDM/NIDDM. Conclusion: Dyslipidemia and myocardial inflammation seem to be the major determinants of diabetic CAD complications. Dysregulation in pro-oxidative enzymes might be attributable to the severity of CAD and oxidative stress levels in all included patients undergoing CABG.

Effect of hypertriglyceridemia in dyslipidemia-induced impaired glucose tolerance and sex differences in dietary features associated with hypertriglyceridemia among the Japanese population: The Gifu Diabetes Study

AIMS/INTRODUCTION

The mechanisms underlying hypertriglyceridemia-induced impaired glucose tolerance in Japanese individuals remain unclear. We aimed to evaluate the effect of hypertriglyceridemia on glucose metabolism in comparison with that of increased low-density lipoprotein or decreased high-density lipoprotein levels and to elucidate the sex differences in hypertriglyceridemia-related dietary intake among Japanese individuals.

MATERIALS AND METHODS

We randomly selected 898 (384 men and 514 women) participants aged 40-78 years in the Gifu Diabetes Study; those taking medication for dyslipidemia or diabetes mellitus were excluded. Serum levels of glucose metabolism parameters and the food frequency were measured cross-sectionally. The glycated hemoglobin was measured again after 5 years.

RESULTS

Glucose metabolism parameters and the percentage of individuals with impaired glucose tolerance were significantly higher in the high triglyceride group in men and women. Similar trends were observed in the low high-density lipoprotein group, but only in men. Meanwhile, only the homeostasis model assessment of insulin resistance was higher in the high low-density lipoprotein group. In non-obese men, the percentage of energy intake from alcohol per total daily energy intake was significantly greater in the high triglyceride group. In obese women, the total energy intake was significantly greater in the high triglyceride group. At the 5-year follow up, the risk of elevated glycated hemoglobin levels with hypertriglyceridemia was increased in men.

CONCLUSIONS

Hypertriglyceridemia is a stronger risk factor for impaired glucose tolerance than increased low-density lipoprotein or decreased high-density lipoprotein. For dietary habits, increased daily alcohol energy intake in non-obese men and increased total energy intake in obese women were associated with hypertriglyceridemia.

Glucose, lipid and oxidative stress lowering activity of the aqueous extract from leafy stems of Cissus polyantha Gilg & Brandt in dexamethasone-induced hyperglycemia in rats

Background

Diabetes mellitus is a metabolic disorder characterised by chronic hyperglycemia. The present research work aimed to evaluate the hypoglycaemic, hypolipidemic and antioxidant effects of leafy stems of Cissus polyantha Gilg & Brandt in insulin resistant rats.

Methods

The oral glucose tolerance test (OGTT) was performed in normal rats. Hyperglycemia was induced for 8 days by a daily subcutaneous injection of dexamethasone (1 mg/kg) one hour after pretreatment of animals with metformin (40 mg/kg) and C. polyantha extract (111, 222 and 444 mg/kg). Body weight, blood glucose, insulin level, lipid profile, insulin biomarkers, cardiovascular indices and oxidative stress biomarkers were evaluated.

Results

For OGTT, the extract (444 mg/kg) produced a significant drop in blood sugar at the 60th (p < 0.01), 90th (p < 0.01) and 120th min (p < 0.05). Morever, the extract at doses of 222 and 111 mg/kg significantly reduced blood sugar at the 60th (p < 0.01) and 90th min (p < 0.05) respectively. Otherwise, C. polyantha (444 and 222 mg/kg) significantly (p < 0.001) increased body weight and decreased blood sugar on the 4th and 8th days of treatment in insulin resistant rats. The extract also significantly decreased (p < 0.001) serum insulin level, hyperlipidemia, insulin resistance index and cardiovascular indices, and increased gluthathione level, and superoxide dismutase and catalase activity.

Conclusion

The aqueous extract of Cissus polyantha leafy stems (AECPLS) possess hypoglycemic, hypolipidemic and antioxidant activities that could justify its use in traditional medicine for the prevention and treatment of diabetes mellitus and its complications.

Hypoglycemic activity of the ethyl acetate extract from Smilax glabra Roxb in mice: Biochemical and histopathological studies

Objectives

This research was carried out to investigate the hypoglycemic activity of the ethyl acetate (EtOAc) extract from the roots of Smilax glabra Roxb, which strongly exhibit inhibitory activity against α-glucosidase and α-amylase on in vivo type 2 diabetic model.

Materials and Methods

Column chromatography combined with crystallization was used to isolate the active fraction and compounds. Chemical structures of the compounds were determined based on the analysis of the spectroscopic data and comparison with the literature data. The α-glucosidase inhibitory activity (AGI) and the α-amylase inhibitory activity (AAI) were determined quantitatively spectrophotometrically using p-nitrophenyl α-D-glucopyranoside and soluble starch as substrates, respectively. The hypoglycemic activity was examined by evaluating its effects on glucose and insulin levels, insulin resistance, and histopathology of the pancreatic islets and livers in diabetic induced mice administrated with nicotinamide-streptozotocin.

Results

The EtOAc extract and the bioactive compounds astilbin and 5-O-caffeoylshikimic acid in the extract were isolated and confirmed in structures, AGI, and AAI. The treatment at the doses of 500 and 1000 µg/kg of body weight reduced blood glucose levels down to the physiological level of the physical controls in the diabetic mice after two weeks (P<0.05). Moreover, the treatment improved insulin sensitivity. Histopathology analysis showed recovering effects in the size of the pancreatic islets and no damaging effects on the liver after treatment compared with the control group.

Conclusion

Our data suggest that the EtOAc extract possesses hypoglycemic activity and has an antidiabetic potential for therapeutic applications.

Hypoglycemic, antidyslipidemic and antioxydant effects of Vitellaria paradoxa barks extract on high-fat diet and streptozotocin-induced type 2 diabetes rats

Backgroud

Vitellaria paradoxa is a plant belonging to the Sapotaceae family and used in traditional medicine in the treatment of diabetes mellitus. The aim of this work was to evaluate the hypoglycemic, antidyslipidemic and antioxidant effects of V. paradoxa on type 2 diabetic rats.

Methods

To induce type 2 diabetes mellitus (T2DM), animals were fed a high-fat diet for 4 weeks followed by an intraperitoneal injection of 35 mg/kg of streptozotocin. Diabetic rats were divided into groups and treated for 28 days with V. paradoxa extract (AEVP) at doses of 125, 250 and 500 mg/kg. Body weight, urine volume, food and water consumption were assessed at the start and end of treatment. The glucose tolerance test was performed on the last day of treatment. Blood samples were taken for the assay of biochemical parameters, organs (kidneys and liver) for markers of oxidative stress and pancreas for histological sections.

Results

AEVP (250 and 500 mg/kg) improved the drop in body weight, polyphagia, polydipsia and polyuria in diabetic rats. AEVP significantly reduced the concentrations of glucose, total cholesterol, triacylglycerol, urea, creatinine, activities of transaminases, and increased the levels of high density lipoprotein cholesterol and serum insulin. AEVP resulted in a decrease in malondialdehyde levels and an increase in catalase and superoxide dismutase activities. An increase in the size and number of islets in the pancreas has also been observed after administration of the extract.

Conclusion

AEVP has antidiabetic, antidyslipidemic and antioxidant properties, thus confirming its traditional use for the treatment of diabetes. These effects could be due to the presence of phytoconstituents, phenols and flavonoids presents in the plant extract.

Evaluation of skin absorption of the Citrullus colocynthis in treatment of type II diabetic patients

Background and purpose

Nowadays, among the herbal medicines utilized to treat diabetes, Citrullus colocynthis (CCT) is highly noticeable as it reduces blood glucose (BG) and stimulating insulin secretion. However, long-term oral consumption of this herbal medicine has often associated with digestive complications. In this study, skin absorption of CCT as a new therapeutic approach in the treatment of type II diabetic patients has been surveyed.

Materials and methods

40 patients with type II diabetic (aged 45-65) were selected. Participants were asked for placing their metatarsus daily in a decoction containing 2% CCT solution for 40-60 min each day and continuing that for 10 days. Blood and urine samples of patients collected at the beginning and the end of the study. The samples were examined for the BG levels, serum insulin content, lipid profiles, hepatic enzymes, urea, creatinine, and microalbuminuria, The quantitative insulin sensitivity check index (QUICKI), Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), homeostasis model assessment of β-cell function (HOMA-β) and disposition index (DI) indicators were also calculated.

Results

Local treatment of CCT could significantly decrease BG levels, stimulate insulin secretion and improve the function of pancreatic beta cells. It also decreased serum urea levels comparing to pre-treatment levels (p < 0.05) but there was no significant change in creatinine levels, lipid profiles, hepatic enzymes, micro-albuminuria, and other insulin sensitivity indexes.

Conclusion

This study demonstrated that the CCT plant can also have systemic therapeutic effects on type II diabetic patients through dermal absorption.

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

AIM

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Impaired secretion of active GLP-1 in patients with hypertriglyceridaemia: A novel lipotoxicity paradigm?

BACKGROUND

Lipotoxicity plays an important role in the pathogenesis of β-cell dysfunction. Glucagon-like peptide-1 (GLP-1) is an incretin hormone that exerts beneficial effects on the number and function of islet β cells. However, the effect of lipotoxicity on GLP-1 secretion is still unknown.

METHODS

Twenty-five patients who were newly diagnosed with diabetes were recruited from 400 subjects based on 75-g Oral Glucose Tolerance Test. Patients were divided into diabetes (DM) and DM combined with hypertriglyceridaemia (DM + HTG) groups according to their serum triglyceride (TG) levels. Seventy-one normal controls and 17 patients with isolated hypertriglyceridaemia were matched by age and gender.

RESULTS

Total and active fasting GLP-1 and 2-hour GLP-1 levels were not significantly altered among the 4 groups. However, total and active ΔGLP-1 levels (the difference between 2-hour GLP-1 and fasting GLP-1 levels) were significantly reduced in the isolated HTG, DM, and DM + HTG groups, particularly the DM + HTG group. The ratio of serum active GLP-1 (AGLP-1) to total GLP-1 (TGLP-1) levels was also decreased in patients with isolated HTG, suggesting that active GLP-1 secretion may be more seriously impaired. Both ΔTGLP-1 and ΔAGLP-1 levels were negatively correlated with serum TG levels, body mass index and fasting plasma glucose (FPG) levels and positively correlated with HDL-C levels. According to the multivariate linear regression analysis, only TG and FPG levels were independently associated with ΔTGLP-1 and ΔAGLP-1 levels.

CONCLUSION

Impaired GLP-1 secretion was associated with hypertriglyceridaemia and diabetes, and a more obvious association was noted in hypertriglyceridaemic patients with diabetes.

Centella asiatica enhances hepatic antioxidant status and regulates hepatic inflammatory cytokines in type 2 diabetic rats

CONTEXT

Neutralizing the over-activation of oxidative stress and inflammation remains an important goal in the management of type 2 diabetes mellitus (T2DM). Centella asiatica (L.) Urban (Apiaceae) (CA) has been used in traditional folklore in Africa and Asia to treat various ailments including diabetes.

OBJECTIVE

We investigated the hepatic antioxidant and anti-inflammatory potential of methanol extract of CA leaves in T2DM.

MATERIALS AND METHODS

T2DM was induced in male Sprague-Dawley rats with 10% fructose in drinking water for 14 days followed by a single intraperitoneal injection of streptozotocin (40 mg/kg b.wt). Hepatic oxidant/antioxidant status was assessed by measuring the concentrations of malondialdehyde (MDA), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), Trolox equivalent antioxidant capacity (TEAC), reduced glutathione (GSH) and activities of glutathione S-transferase (GST) and glutathione peroxidase (GPX). The concentrations of cytokines IL-1β, IL-4, IL-6, IL-10, MCP-1 and TNF-α in the liver were determined.

RESULTS

Diabetes increased MDA formed (47%) and reduced FRAP (20%), TEAC (15%), GSH levels (32%), significantly; decreased GST and GPX activities in the liver and elevated levels of cytokines studied. Treatment of diabetic rats with 500 mg/kg b.wt CA for 14 days decreased MDA (44%); elevated FRAP (15%) and GSH (131%) levels and increased the activities of GST and GPX by 16%. Hepatic concentrations of IL-1β, MCP-1 and TNF-α in DCA group were reduced to 68%, 75% and 63% of DC values, respectively.

CONCLUSIONS

The antioxidant and anti-inflammatory properties of CA may protect tissues such as the liver from diabetes-induced oxidative damage.

Metformin ameliorates diabetic nephropathy in a rat model of low-dose streptozotocin-induced diabetes

The present study aimed to explore the renoprotective effect of metformin on diabetic nephropathy in type 2 diabetic rats. A rat model of type 2 diabetic nephropathy (T2DN) was successfully induced via a high-fat diet combined with a single low-dose of streptozotocin. Metformin was administered intragastrically for 13 weeks, and fasting blood glucose (FBG), total cholesterol (TC), triglycerides (TG), HDL-c, LDL-c, urinary and serum creatinine levels were subsequently examined at the end of administration. Renal function was determined after the treatment protocol. Expression levels of transforming growth factor (TGF)-β1 and connective tissue growth factor (CTGF) were assessed via immunohistochemical analysis. Superoxide dismutase activity, malondialdehyde content and glutathione peroxidase levels were assessed in kidney tissues using commercially available kits. The results of the present study demonstrated that metformin administration significantly decreased the levels of serum blood urea nitrogen, serum creatinine, creatinine clearance, urinary albumin excretion and fasting blood glucose in rats with T2DN. Furthermore, TG, TC and LDL-c levels were significantly decreased following metformin treatment, whereas HDL-c was increased. Metformin treatment significantly increased SOD activity and significantly decreased malondialdehyde levels, as compared with the model group. It was also demonstrated that metformin administration significantly decreased the expression levels of TGF-β1 and attenuated the morphological changes associated with T2DN in rats. These data clearly demonstrated the renoprotective effects of metformin against the development and progression of T2DN in rats. The underlying mechanism of this protective effect may be associated with glycemic control, lipid metabolism, and anti-oxidative and anti-inflammatory functions.

The association between Western and Prudent dietary patterns and fasting blood glucose levels in type 2 diabetes and normal glucose metabolism in older Australian adults

High blood glucose and type 2 diabetes are associated with a range of adverse health and cognitive outcomes. One factor that contributes to high blood glucose and type 2 diabetes is dietary intake. This study investigated the relationship between dietary patterns, fasting blood glucose and diabetes status in a sample of 209 participants aged 60–65. Blood plasma glucose was measured from venous blood samples. Individual Prudent and Western dietary patterns were estimated from a self-completed food frequency questionnaire. The relationship between dietary patterns, diabetes, and blood glucose was assessed via general linear model analyses controlling for age, sex, height, and total caloric intake. Results indicated that there was no association between Prudent diet and fasting blood glucose levels, or type 2 diabetes. In contrast, an individual in the upper tertile for Western dietary score had a significantly higher risk of having diabetes than an individual in the lower tertile for Western dietary score. However, there was no significant association between Western diet and fasting blood glucose. Western diet may be associated with type 2 diabetes through mechanisms beyond impacting blood plasma glucose directly. The fact that the association between Western diet and type 2 diabetes remained even when total caloric intake was controlled for highlights the need for policy and population health interventions targeting the reduction of unhealthy food consumption.

Antidiabetic, hypolipidemic and hepatoprotective effects of Arctium lappa root's hydro-alcoholic extract on nicotinamide-streptozotocin induced type 2 model of diabetes in male mice

OBJECTIVE

Arctium lappa (burdock), (A. lappa) root has hypoglycemic and antioxidative effects, and has been used for treatment of diabetes in tradition medicine. This study was conducted to evaluate the antidiabetic and hypolipidemic properties of A. lappa root extract on nicotinamide-streptozotocin (NA-STZ)-induced type2 diabetes in mice.

MATERIALS AND METHODS

In this investigation, 70 adult male NMRI mice (30-35g) randomly divided into 7 groups (n=10) as follow: 1-control, 2-type 2 diabetic mice, 3-diabetic mice that received glibenclamide (0.25 mg/kg) as an anti-diabetic drug, 4, 5, 6 and 7- diabetic and normal animals that were pre-treated with 200 and 300 mg/kg A. lappa root extract, respectively, for 28 days. Diabetes has been induced by intraperitoneal injection of NA and STZ. Finally, the blood sample was taken and insulin, glucose, SGOT, SGPT, alkaline phosphatase, leptin and lipid levels was evaluated.

RESULTS

Induction of diabetes decreased the level of insulin, leptin and high density lipoprotein (HDL) and increased the level of other lipids, glucose, and hepatic enzymes significantly (p<0.05). Administration of both doses of the extract significantly decreased the level of triglyceride, very low density lipoprotein, glucose and alkaline phosphatase in diabetic mice (p<0.05). Insulin levels increased in animals treated with 200 mg/kg (p<0.05) and HDL and leptin levels increased in animals treated with 300 mg/kg of the extract (p<0.01).

CONCLUSION

The results showed that A. lappa root extract, at specific doses, has an anti-diabetic effect through its hypolipidemic and insulinotropic properties. Hence, this plant extract may be beneficial in the treatment of diabetes.

Effects of hydroalcoholic extract of Rhus coriaria seed on glucose and insulin related biomarkers, lipid profile, and hepatic enzymes in nicotinamide-streptozotocin-induced type II diabetic male mice

Type 2 diabetes often leads to dislipidemia and abnormal activity of hepatic enzymes. The purpose of this study was to evaluate the antidiabetic and hypolipidemic properties of Rhus coriaria (R. coriaria) seed extrac on nicotinamide-streptozotocin induced type 2 diabetic mice. In this experimental study, 56 male Naval Medical Research Institute mice (30-35 g) were randomly separated into seven groups: control, diabetic group, diabetic mice treated with glibenclamide (0.25 mg/kg, as standard antidiabetic drug) or R. coriaria seed extract in doses of 200 and 300 mg/kg, and control groups received these two doses of extract orally for 28 days. Induction of diabetes was done by intraperitoneal injection of nicotinamide and streptozotocin. Ultimately, body weight of mice, blood levels of glucose, insulin, hepatic enzymes, leptin, and lipid profile were assayed. After induction of type 2 diabetes, level of glucose, cholesterol, low density lipoprotein, serum glutamic oxaloacetic transaminase, and serum glutamic pyruvic transaminase increased and level of insulin and high density lipoprotein decreased remarkably. Administration of both doses of extract decreased level of glucose and cholesterol significantly in diabetic mice. LDL level decreased in treated group with dose of 300 mg/kg of the extract. Although usage of the extract improved level of other lipid profiles, insulin and hepatic enzymes, changes weren't significant. This study showed R. coriaria seeds administration has a favorable effect in controlling some blood parameters in type 2 diabetes. Therefore it may be beneficial in the treatment of diabetes.

PPARα Agonist Fenofibrate Reduced the Secreting Load of β-Cells in Hypertriglyceridemia Patients with Normal Glucose Tolerance

Hypertriglyceridemia is an important risk factor associated with insulin resistance and β-cell dysfunction. This study investigated the effects of hypertriglyceridemia and fenofibrate treatment on insulin sensitivity and β-cell function in subjects with normal glucose tolerance. A total of 1974 subjects with normal glucose tolerance were divided into the normal TG group (NTG group, n = 1302) and hypertriglyceridemia group (HTG group, n = 672). Next, 92 patients selected randomly from 672 patients with hypertriglyceridemia were assigned to a 24-week fenofibrate treatment. The HTG group had increased waist circumference (WC), body mass index (BMI), homeostasis model assessment of insulin resistance (HOMA-IR), and homeostasis model assessment of β-cell function (HOMA-β) and decreased high-density lipoprotein cholesterol (HDL-C) compared with the NTG group (all P < 0.01). The 24-week fenofibrate treatment significantly decreased the WC, BMI, TG, HOMA-IR, and HOMA-β levels and increased the HDL-C levels in the patients with hypertriglyceridemia (WC, BMI, and HOMA-IR: P < 0.05; TG, HDL-C, and HOMA-β: P < 0.01). The fenofibrate treatment significantly alleviated insulin resistance and reduced the secreting load of β-cells in the hypertriglyceridemia patients with normal glucose tolerance.

Over-nutrient environment during both prenatal and postnatal development increases severity of islet injury, hyperglycemia, and metabolic disorders in the offspring

Prenatal and postnatal over-nutrition has emerged as a new health issue contributing to metabolic disorders in early development of the offspring. Accumulating evidence has suggested that adverse prenatal and postnatal environments gave rise to the predisposition to metabolic syndromes including hyperglycemia, obesity, and diabetes. However, little research has concentrated on the effects of exposures to both adverse conditions before and after birth of the offspring. In this study, we aimed to investigate whether prenatal and postnatal over-nutrition is able to cause metabolic disorders to female mice feed on high-fat/fructose diet (HFFD) as well as their offspring. Female mice were fed on either HFFD or a normal chow diet (NC), while their offspring were divided into four experimental groups as NC/NC, HFFD/NC, NC/HFFD, and HFFD/HFFD (prenatal/postnatal diet order), respectively. Both NC/HFFD and HFFD/HFFD offspring exhibited obvious body weight and fat content gain, hyperglycemia, and severe insulin resistance. Interestingly, when compared to NC/HFFD offspring, the HFFD/HFFD offspring exhibited more severe alterations in their metabolism and dysfunctions on pancreatic β-cells, suggesting a potential impact of prenatal HFFD on the programming of pancreatic β-cell deficiency in the fetus. Meanwhile, the results from HFFD/NC mice indicated that a balance diet after birth partially compensated the adverse prenatal HFFD impact. In conclusion, this study demonstrated that prenatal and postnatal over-nutrition increases severity of islet injury, hyperglycemia, and metabolic disorders in the offspring.

Clinical characteristics and beta cell function in Chinese patients with newly diagnosed type 2 diabetes mellitus with different levels of serum triglyceride

BACKGROUND

To explore clinical characteristics and beta cell function in Chinese patients with newly diagnosed drug naive type 2 diabetes mellitus (T2DM) with different levels of serum triglyceride (TG).

METHODS

Patients with newly diagnosed T2DM (n = 624) were enrolled and divided into different groups according to levels of serum TG. All patients underwent oral glucose tolerance tests and insulin releasing tests. Demographic data, lipid profiles, glucose levels, and insulin profiles were compared between different groups. Basic insulin secretion function index (homeostasis model assessment for beta cell function index, HOMA-β), modified beta cell function index (MBCI), glucose disposition indices (DI), and early insulin secretion function index (insulinogenic index, IGI) were used to evaluate the beta cell function.

RESULTS

Patients of newly diagnosed T2DM with hypertriglyceridemia were younger, fatter and had worse lipid profiles, glucose profiles, and high insulin levels than those with normal TG. There is no difference in early phase insulin secretion among groups of newly diagnosed T2DM patients with different TG levels. The basal beta cell function (HOMA-β and MBCI) initially increased along rising TG levels and then decreased as the TG levels rose further. The insulin sensitivity was relatively high in patients with a low level of TG and low with a high level of TG.

CONCLUSIONS

Hypertriglyceridemia influences clinical characteristics and β cell function of Chinese patients with newly diagnosed T2DM. A better management of dyslipidemia may, to some extent, reduce the effect of lipotoxicity, thereby improving glucose homeostasis in patients with newly diagnosed T2DM.

Obese first-degree relatives of patients with type 2 diabetes with elevated triglyceride levels exhibit increased β-cell function

BACKGROUND

Type 2 diabetes mellitus (T2DM) is characterized as a disease continuum that is marked by metabolic changes that are present for several years, sometimes well before frank diagnosis of T2DM. Genetic predisposition, ethnicity, geography, alterations in BMI, and lipid profile are considered important markers for the pathogenesis of T2DM through mechanisms that remain unresolved and controversial. The aim of this study was to investigate the relationship between triglycerides (TGs) and β-cell function, insulin resistance (IR), and insulin sensitivity (IS) in obese first-degree relatives of patients with T2DM (FDR-T2DM) among subjects from central Mexico with normal glucose tolerance (NGT).

METHODS

We studied 372 FDR-T2DM subjects (ages,18-65) and determined body mass index (BMI), fasting plasma glucose (FPG), oral glucose tolerance test (OGTT), insulin, and TGs levels. Subjects were categorized based on glycemic control [NGT, prediabetes (PT2DM), or T2DM]. NGT subjects were further categorized by BMI [normal weight (Ob-) or obese (Ob+)] and TGs levels (TG-, <150 mg/dL, or TG+, ≥150 mg/dL). β-cell function, IR, and IS were determined by the homeostasis model assessment of β-cell function (HOMA2-β), homeostasis model assessment of insulin resistance (HOMA2-IR), and Quantitative Insulin Sensitivity Check Index (QUICKI) indices, respectively.

RESULTS

The obese subjects with elevated TGs levels had 21%-60% increased β-cell function when compared to all groups (P<0.05). In addition, this group had insulin levels, IS, and IR similar to PT2DM. Furthermore, only in obese subjects did TGs correlate with β-cell function (ρ=0.502, P<0.001).

CONCLUSION

We characterized FDR-T2DM subjects from central Mexico with NGT and revealed a class of obese subjects with elevated TGs and β-cell function, which may precede PT2DM.