Thiazolidinediones in patients with type 2 diabetes mellitus and heart failure

Pathophysiology and Advances in the Therapy of Cardiomyopathy in Patients with Diabetes Mellitus

Diabetes mellitus (DM) is known as the first non-communicable global epidemic. It is estimated that 537 million people have DM, but the condition has been properly diagnosed in less than half of these patients. Despite numerous preventive measures, the number of DM cases is steadily increasing. The state of chronic hyperglycaemia in the body leads to numerous complications, including diabetic cardiomyopathy (DCM). A number of pathophysiological mechanisms are behind the development and progression of cardiomyopathy, including increased oxidative stress, chronic inflammation, increased synthesis of advanced glycation products and overexpression of the biosynthetic pathway of certain compounds, such as hexosamine. There is extensive research on the treatment of DCM, and there are a number of therapies that can stop the development of this complication. Among the compounds used to treat DCM are antiglycaemic drugs, hypoglycaemic drugs and drugs used to treat myocardial failure. An important element in combating DCM that should be kept in mind is a healthy lifestyle-a well-balanced diet and physical activity. There is also a group of compounds-including coenzyme Q10, antioxidants and modulators of signalling pathways and inflammatory processes, among others-that are being researched continuously, and their introduction into routine therapies is likely to result in greater control and more effective treatment of DM in the future. This paper summarises the latest recommendations for lifestyle and pharmacological treatment of cardiomyopathy in patients with DM.

Effect of oral cannabis administration on the fat depots of obese and streptozotocin-induced diabetic rats

The prevalence of obesity and insulin-resistance is on the rise, globally. Cannabis have been shown to have anti-diabetic/obesity properties, however, the effect mediated at various fat depots remains to be clarified. The aim of this study was to (1) investigate the anti-diabetic property of an oral cannabis administration in an obese and streptozotocin-induced diabetic rat model and (2) to determine and compare the effect mediated at the peritoneal and intramuscular fat level. Cannabis concentration of 1.25 mg/kg body weight (relative to THC content) was effective in reversing insulin-resistance in the rat model, unlike the other higher cannabinoid concentrations. At the peritoneal fat level, gene expression of fat beigeing markers, namely Cidea and UCP1, were significantly increased compared to the untreated control. At the intramuscular fat level, on the other hand, CE1.25 treatment did not promote fat beigeing but instead significantly increased mitochondrial activity, relative to the untreated control. Therefore, these findings indicate that the mechanism of action of oral cannabis administration, where glucose and lipid homeostasis is restored, is not only dependent on the dosage but also on the type of fat depot investigated.

Incretin-based therapy: Is the risk of pancreatitis driven by cardiovascular disease?

Incretin-based therapies are normally prescribed to individuals with type 2 diabetes but has recently come under scrutiny due to the possibility of associated pancreatitis. A 2014 systematic review published in the BMJ found no increase risk of acute pancreatitis in adults with type 2 diabetes, as partly evident from the meta-analysis of RCTs (OR=1.11, 95% CI 0.57-2.17). By contrast, a second meta-analysis added 3 large outcome trials in patients with previous cardiovascular disease to the previous 55 RCTs from Li et al. and showed an increased risk in acute pancreatitis. While the discrepancy in result may be due to better quality large trials, as the authors suggest, it is likely that since the large outcome trials investigated patients with cardiovascular disease, the increased risk is present only in this group.

Prediction of heart failure in patients with type 2 diabetes mellitus- a systematic review and meta-analysis

BACKGROUND

Heart failure (HF) is a major cause of mortality and disability in type 2 diabetes mellitus (T2DM). This study sought to improve the assessment of HF risk in patients with T2DM-a step that would be critical for effective HF screening.

METHODS

A systematic literature search was performed on electronic databases including MEDLINE and EMBASE, using MeSH terms 'heart failure', 'risk factor', 'T2DM', 'cardiac dysfunction', 'stage B heart failure', 'incident heart failure', 'risk assessment', 'risk impact', 'risk score', 'predictor', 'prediction' and related free text terms. The search was limited to human studies in full-length publications in English language journal from 1946 to 2014. Univariable and multivariable relative risk (RR) and hazard ratio (HR) were obtained from each study.

RESULTS

Twenty-one studies (n=1111,569, including 507,637 subjects with T2DM) were included in this analysis with a follow-up ranging from 1 to 12 years. Associations between incident HF and risk variables described in ≥3 studies were reported. This association was greatest for insulin use (HR 2.48; 1.24-4.99), HbA1c 7.0-8.0% (2.41; 1.62-3.59), 5 years increase in age (1.47; 1.25-1.73), fasting glucose (1.28; 1.10-1.51 per standard deviation) and HbA1c (1.18; 1.14-1.23 each 1% increase). After adjustment for confounders, there were strong associations with coronary artery disease (1.77; 1.31, 2.39), HbA1c ≥ 10% (1.66; 1.45-1.89), insulin use (1.43; 1.14-1.79), HbA1c 9.0-10.0% (1.31; 1.14-1.50), fasting glucose (1.27; 1.10-1.47 per standard deviation) and 5 years increase in age (1.26; 1.13-1.40).

CONCLUSION

Among patients with T2DM, five common clinical variables are associated with significantly increased risk of incident HF.

Differential roles of PPARγ vs TR4 in prostate cancer and metabolic diseases

Peroxisome proliferator-activated receptor γ (PPARγ, NR1C3) and testicular receptor 4 nuclear receptor (TR4, NR2C2) are two members of the nuclear receptor (NR) superfamily that can be activated by several similar ligands/activators including polyunsaturated fatty acid metabolites, such as 13-hydroxyoctadecadienoic acid and 15-hydroxyeicosatetraenoic acid, as well as some anti-diabetic drugs such as thiazolidinediones (TZDs). However, the consequences of the transactivation of these ligands/activators via these two NRs are different, with at least three distinct phenotypes. First, activation of PPARγ increases insulin sensitivity yet activation of TR4 decreases insulin sensitivity. Second, PPARγ attenuates atherosclerosis but TR4 might increase the risk of atherosclerosis. Third, PPARγ suppresses prostate cancer (PCa) development and TR4 suppresses prostate carcinogenesis yet promotes PCa metastasis. Importantly, the deregulation of either PPARγ or TR4 in PCa alone might then alter the other receptor's influences on PCa progression. Knocking out PPARγ altered the ability of TR4 to promote prostate carcinogenesis and knocking down TR4 also resulted in TZD treatment promoting PCa development, indicating that both PPARγ and TR4 might coordinate with each other to regulate PCa initiation, and the loss of either one of them might switch the other one from a tumor suppressor to a tumor promoter. These results indicate that further and detailed studies of both receptors at the same time in the same cells/organs may help us to better dissect their distinct physiological roles and develop better drug(s) with fewer side effects to battle PPARγ- and TR4-related diseases including tumor and cardiovascular diseases as well as metabolic disorders.

Use of noninsulin antidiabetic medications in hospitalized patients

Noninsulin antidiabetic medications coupled with diet and exercise are effective in managing most patients with type 2 diabetes. However, it is essential to evaluate the safety and effectiveness of the home antidiabetic medication regimen when the patient is hospitalized. Prescribers need to be aware of the mechanism of action of each class, contraindications, precautions, and adverse effects to formulate a safe and effective management plan. This article details the different classes of noninsulin antidiabetic medications, the mechanism of action, metabolism, elimination, dose form, usual and maximum doses, contraindications, precautions, common adverse reactions, and implications for use in the hospitalized patient.

Oral salmon calcitonin attenuates hyperglycaemia and preserves pancreatic beta-cell area and function in Zucker diabetic fatty rats

BACKGROUND AND PURPOSE

Oral salmon calcitonin (sCT), a dual-action amylin and calcitonin receptor agonist, improved glucose homeostasis in diet-induced obese rats. Here, we have evaluated the anti-diabetic efficacy of oral sCT using parameters of glycaemic control and beta-cell morphology in male Zucker diabetic fatty (ZDF) rats, a model of type 2 diabetes.

EXPERIMENTAL APPROACH

Male ZDF rats were treated with oral sCT (0.5, 1.0 or 2 mg·kg(-1) ) or oral vehicle twice daily from age 8 to 18 weeks. Zucker lean rats served as control group. Fasting and non-fasted blood glucose, glycosylated haemoglobin (HbA1c) and levels of pancreas and incretin hormones were determined. Oral glucose tolerance test and i.p. glucose tolerance test were compared, and beta-cell area and function were evaluated.

KEY RESULTS

Oral sCT treatment dose-dependently attenuated fasting and non-fasted hyperglycaemia during the intervention period. At the end of the study period, oral sCT treatment by dose decreased diabetic hyperglycaemia by ∼9 mM and reduced HbA1c levels by 1.7%. Furthermore, a pronounced reduction in glucose excursions was dose-dependently observed for oral sCT treatment during oral glucose tolerance test. In addition, oral sCT treatment sustained hyperinsulinaemia and attenuated hyperglucagonaemia and hypersecretion of total glucagon-like peptide-1 predominantly in the basal state. Lastly, oral sCT treatment dose-dependently improved pancreatic beta-cell function and beta-cell area at study end.

CONCLUSIONS AND IMPLICATIONS

Oral sCT attenuated diabetic hyperglycaemia in male ZDF rats by improving postprandial glycaemic control, exerting an insulinotropic and glucagonostatic action in the basal state and by preserving pancreatic beta-cell function and beta-cell area.

Borapetoside C from Tinospora crispa improves insulin sensitivity in diabetic mice

Diabetes mellitus (DM) often leads to disability from vascular complications and neurological complications. Tinospora crispa has been widely used in Asia and Africa as a remedy for diabetes and other diseases. In this study, we investigated the hypoglycemic actions of borapetoside C isolated from T. crispa, and the mechanisms underlying its actions. Acute treatment with borapetoside C (5mg/kg, i.p.) attenuated the elevated plasma glucose induced by oral glucose in normal and type 2 DM (T2DM) mice. Compared to the effect of injected insulin (0.5 IU/kg), borapetoside C caused a more prominent increase of glycogen content in skeletal muscle of T2DM mice, but a less increase in type 1 DM (T1DM) mice. Combined treatment of a low dose borapetoside C (0.1mg/kg, i.p.) plus insulin enhanced insulin-induced lowering of the plasma glucose level and insulin-induced increase of muscle glycogen content. Continuous treatment with 5mg/kg borapetoside C (twice daily) for 7 days increased phosphorylation of insulin receptor (IR) and protein kinase B (Akt) as well as the expression of glucose transporter-2 (GLUT2) in T1DM mice. Combined treatment of a low dose borapetoside C (0.1mg/kg, twice daily) plus insulin for 7 days enhanced insulin-induced IR and Akt phosphorylation and GLUT2 expression in the liver of T1DM mice. This study proved that borapetoside C can increase glucose utilization, delayed the development of insulin resistance and enhanced insulin sensitivity. The activation of IR-Akt-GLUT2 expression and the enhancement of insulin sensitivity may contribute to the hypoglycemic action of borapetoside C in diabetic mice.

Comparing the effects of insulin glargine and thiazolidinediones on plasma lipids in type 2 diabetes: a patient-level pooled analysis

BACKGROUND

The prevalence of dyslipidaemia and the risk of cardiovascular disease are elevated in patients with type 2 diabetes. This analysis compared the effects of insulin glargine versus thiazolidinediones (TZDs) on lipid profiles.

METHODS

Patient-level data were pooled from two randomized clinical studies. The population included 552 men and women aged >18 years, diagnosed with type 2 diabetes for at least 6 months, on metformin and/or sulphonylurea, and with A(1C) ≥7.5% and <12.0% at screening. Lipid outcome measures included change from baseline in lipid levels [low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), total cholesterol, triglycerides, and free fatty acids] and attainment of lipid goals for LDL-C, non-HDL-C, and triglycerides.

RESULTS

Both insulin glargine and TZDs improved lipid profiles from baseline values. Compared with TZDs, treatment with insulin glargine led to 7.9% greater reduction in LDL-C (p < 0.0003), 7.5% greater reduction in non-HDL-C (p < 0.0001), and 7.8% greater reduction in total cholesterol (p < 0.0001), whereas the HDL-C increase with TZD was 7.6% greater than that with insulin glargine (p < 0.0001). The percentage of patients attaining the lipid goals was comparable between insulin glargine and pioglitazone, but lower for rosiglitazone. Insulin glargine improved glycaemic control more than TZDs; however, insulin glargine caused more hypoglycaemia. Treatment with TZDs caused more weight gain and peripheral oedema.

CONCLUSION

These findings suggest that the favourable effects of insulin glargine on plasma lipid profiles should be considered among the advantages of treatment with insulin glargine as they are for TZDs.

A novel oral form of salmon calcitonin improves glucose homeostasis and reduces body weight in diet-induced obese rats

AIM

To investigate the effects of acute and chronic administration of a novel oral formulation of salmon calcitonin (sCT) on glycaemic control, glucose homeostasis and body weight regulation in diet-induced obese (DIO) rats-an animal model of obesity-related insulin resistance and type 2 diabetes.

METHODS

DIO rats were acutely given a single dose of oral sCT (0.5 and 2 mg/kg), its oral vehicle N-(5-chlorosalicyloyl)-8-aminocaprylic acid (5-CNAC) or injectable sCT (5 and 10 µg/kg) (n = 8), followed by oral glucose tolerance test (OGTT). Other DIO rats were chronic treated twice daily with oral vehicle 5-CNAC (n = 6), oral sCT (0.5 and 2 mg/kg) or injectable sCT (10 µg/kg) (n = 8). Fasting and postprandial glucose and pancreatic hormones, body weight and insulin sensitivity were assessed.

RESULTS

A single dose of oral sCT acutely reduced glucose and insulin area under the curve during OGTT by approximately 65 and 85%, respectively, compared with vehicle (p < 0.001). Chronic treatment with oral sCT significantly reduced both fasting and postprandial glucose and insulin levels by approximately 1.5 mM and 65%, respectively, compared with vehicle. Oral sCT concomitantly improved insulin sensitivity (homeostatic model assessment, HOMA). In contrast, injectable sCT resembling higher systemic exposure did not improve glycaemic control, either acutely or during chronic treatment. Furthermore, both oral and injectable sCT reduced body weight by 15% compared with vehicle (p < 0.05).

CONCLUSION

A novel oral form of sCT showed antidiabetic effects in DIO rats by improving glycaemic control, glucose homeostasis, insulin sensitivity and body weight.

Hexarelin Signaling to PPARgamma in Metabolic Diseases

Investigating the metabolic functions of the nuclear receptor peroxisome proliferator-activated receptor γ (PPARγ) has been extremely rewarding over the past years. Uncovering the biologic roles of PPARγ and its mechanism of action has greatly advanced our understanding of the transcriptional control of lipid and glucose metabolism, and compounds such as thiazolidinediones which directly regulate PPARγ have proven to exhibit potent insulin-sensitizer effects in the treatment of diabetes. We review here recent advances on the emerging role of growth hormone releasing peptides in regulating PPARγ through interaction with scavenger receptor CD36 and ghrelin GHS-R1a receptor. With the impact that these peptides exert on the metabolic pathways involved in lipid metabolism and energy homeostasis, it is hoped that the development of novel approaches in the regulation of PPAR functions will bring additional therapeutic possibilities to face problems related to metabolic diseases.

Myricetin Ameliorates Defective Post-Receptor Insulin Signaling via β-Endorphin Signaling in the Skeletal Muscles of Fructose-Fed Rats

β-Endorphin plays a major role in the amelioration of insulin resistance. The present study documents that myricetin (3,5,7,3′, 4′, 5′-hexahydroxyflavone) ameliorates insulin resistance by enhancing β-endorphin production in insulin-resistant rats. The rats were induced for insulin resistance by feeding them a diet containing 60% fructose for 6 weeks. The degree of insulin resistance was measured by the homeostasis model assessment of basal insulin resistance (HOMA-IR). The plasma levels of insulin and β-endorphin were measured by an enzyme-linked immunosorbent assay. The insulin receptor-related signaling mediators in the soleus muscles of rats were evaluated by immunoprecipitation or immunoblotting. Myricetin was injected daily (1 mg kg⁻¹ per injection, thrice daily) for 14 days. Consequently, the high-glucose plasma levels in fructose-fed rats decreased significantly concomitant with an increase in plasma β-endorphin. The reduction of the elevated HOMA-IR index following treatment with myricetin was subsequently inhibited by the administration of β-funaltrexamine hydrochloride (β-FNA) at doses sufficient to block μ-opioid receptors (MOR). The myricetin treatment was also observed to affect the phosphorylation of the insulin receptor, insulin receptor substrate-1, Akt and Akt substrate of 160 kDa, with subsequent effects on glucose-transporter subtype 4 translocation, all of which were blocked by β-FNA pretreatment. These results indicated that enhancement of β-endorphin secretion, which in turn leads to peripheral MOR activation, is involved in the action of myricetin on the amelioration of impaired signaling intermediates downstream of insulin receptors.

A Chinese Herbal Decoction, Dang Gui Bu Xue Tang, Prepared from Radix Astragali and Radix Angelicae sinensis, Ameliorates Insulin Resistance Induced by A High-Fructose Diet in Rats

Dang Gui Bu Xue Tang (DBT), a Chinese medicinal decoction contains Radix Angelicae sinensis (Danggui) and Radix Astragali (Huangqi) at a ratio of 1 : 5, is used commonly for treating women's ailments. This study was conducted to explore the effects of this preparation on insulin resistance in rats fed with 6-week diet containing 60% fructose. Similar to the action of rosiglitazone (4 mg kg(-1) per day by an oral administration), repeated oral administration of DBT (2.5 g kg(-1) per day) for 14 days was found to significantly alleviate the hyperglycemia but made no influence on plasma lipid profiles nor weight gain in fructose chow-fed rats. Also, the higher degree of insulin resistance as measured by homeostasis model assessment of basal insulin resistance in fructose chow-fed rats was significantly decreased by repeated DBT treatment. DBT displays the characteristic of rosiglitazone by increasing the whole-body insulin sensitivity in fructose chow-fed rats after 2-week treatment, as evidenced by the marked elevation of composite whole-body insulin sensitivity index during the oral glucose tolerance test. DBT improves insulin sensitivity through increased post-receptor insulin signaling mediated by enhancements in insulin receptor substrate-1-associated phosphatidylinositol 3-kinase step and glucose transporter subtype 4 translocation in soleus muscles of animals exhibiting insulin resistance. DBT is therefore proposed as potentially useful adjuvant therapy for patients with insulin resistance and/or the patients who wish to increase insulin sensitivity.

Angelica acutiloba root attenuates insulin resistance induced by high-fructose diet in rats

Angelica acutiloba root (Japanese Dong Quai), used for treatment of gynecological disorders, is currently cultivated in Taiwan. The present study evaluated the preventative effect of Angelica acutiloba root (Japanese Dong Quai) on the induction of insulin resistance. Insulin resistance was induced in rats by feeding a high fructose diet for 6 weeks. Thereafter, the rats were maintained on the same diet and treated with oral A. acutiloba root extract or pioglitazone once daily for 8 weeks. At the end of treatment, the degree of basal insulin resistance was measured by homeostasis model assessment (HOMA-IR). Insulin sensitivity was calculated using the composite whole body insulin sensitivity index (ISIcomp). Protein expression was evaluated by immunoblotting. A. acutiloba (300 mg/kg/day) displayed similar characteristics to pioglitazone (20 mg/kg/day) in reducing HOMA-IR and elevating ISIcomp. Elevated glycosylated hemoglobin levels and hyperinsulinemia were ameliorated by A. acutiloba treatment without hepatotoxic or nephrotoxic effects. A. acutiloba treatment improved dyslipidemia, induced lipoprotein lipase activity and enhanced hepatic glycogen accumulation. Further, A. acutiloba treatment enhanced the action of insulin on muscle glucose transporter subtype 4 translocation and attenuated hepatic phosphoenolpyruvate carboxykinase expression. The findings suggest that A. acutiloba may be an effective ethnomedicine for improving insulin sensitivity.

Improved glycemic control with insulin glargine versus pioglitazone as add-on therapy to sulfonylurea or metformin in patients with uncontrolled type 2 diabetes mellitus

OBJECTIVE

To compare glycemic control with add-on insulin glargine versus pioglitazone treatment in patients with type 2 diabetes.

METHODS

This 48-week, multicenter, parallel-group, open-label study randomized 389 adults with poorly controlled type 2 diabetes (glycated hemoglobin A1c [A1C], 8.0% to 12.0%), despite > or =3 months of sulfonylurea or metformin monotherapy, to receive add-on therapy with insulin glargine or pioglitazone. Outcomes included A1C change from baseline to end point (primary), percentage of patients achieving A1C levels < or =7.0%, and changes from baseline in fasting plasma glucose, body mass index, weight, and serum lipids. The safety analysis included incidence of adverse events and rates of hypoglycemia.

RESULTS

At end point, insulin glargine yielded a significantly greater reduction in A1C in comparison with pioglitazone (-2.48% versus -1.86%, respectively; 95% confidence interval, -0.93 to -0.31; P = .0001, 48-week modified intent-to-treat population). Insulin glargine also yielded significantly greater reductions in fasting plasma glucose at all time points (end point difference, -34.9 mg/dL; 95% confidence interval, -47.6 to -22.2; P<.0001). In comparison with pioglitazone, insulin glargine resulted in a lower overall incidence of possibly related treatment-emergent adverse events (12.0% versus 20.7%) and fewer study discontinuations (2.2% versus 9.1%), but a higher rate (per patient-year) of confirmed clinically relevant hypoglycemic episodes (blood glucose <70 mg/dL and all severe hypoglycemia) (4.97 versus 1.04; P<.0001) and severe hypoglycemia (0.07 versus 0.01; P = .0309). Weight and body mass index changes were similar between the 2 treatment groups.

CONCLUSION

The addition of insulin glargine early in the diabetes treatment paradigm in patients for whom sulfonylurea or metformin monotherapy had failed resulted in significantly greater improvements in glycemic control in comparison with the addition of pioglitazone. Although severe hypoglycemia was more frequent in patients with insulin glargine therapy, hypoglycemic events occurred in <5% of patients in the insulin glargine treatment group.

Protective effect of Clerodendron glandulosum extract against experimentally induced metabolic syndrome in rats

CONTEXT

Metabolic syndrome (MetS) has become one of the major health burdens worldwide. To date, no single pharmacological agent has been developed to correct metabolic abnormalities associated with MetS. Use of indigenous medicinal plants as alternative medicines against MetS could be beneficial due to multiple therapeutic usage, easy availability, and relatively few side effects.

OBJECTIVE

To investigate the protective effect of Clerodendron glandulosum Coleb. (Verbenaceae) aqueous leaf extract (CgE) against experimentally induced MetS in rats.

METHODS

Changes in body weight, food and fluid intake, plasma glucose, insulin, fasting insulin resistance index (FIRI), plasma total lipid profile, free fatty acids (FFA), oral glucose tolerance test (OGTT), blood pressure and vascular reactivity have been investigated in various experimental groups.

RESULTS

Fructose+CgE groups recorded significant decrement (P <0.05) in plasma glucose, insulin, FIRI, total cholesterol, triglycerides, LDL, VLDL and FFA, whereas plasma HDL level was significantly increased (P <0.05) along with an efficient clearance of glucose during OGTT and lowered area under curve values. FRU+CgE groups also showed significantly decreased (P <0.05) mean arterial blood pressure along with decreased vasoconstriction and increased vasorelaxation in response to administration of various pharmacological agents. These results were comparable with metformin treated rats.

DISCUSSION

C. glandulosum leaf extract ameliorates experimentally induced MetS by improving dyslipidemia and insulin resistance.

CONCLUSION

This study provides the first pharmacological evidence for the protective role of C. glandulosum leaves against experimentally induced MetS. Thus, therapeutic use of C. glandulosum in controlling MetS is indicated.

Abelmoschus moschatus (Malvaceae), an aromatic plant, suitable for medical or food uses to improve insulin sensitivity

Abelmoschus moschatus (Malvaceae) is an aromatic and medicinal plant, distributed in many parts of Asia, including south Taiwan. The present study was undertaken to clarify whether the herb is effective in improving insulin resistance. Insulin resistance in rats was induced by a diet containing 60% fructose for 6 weeks. The degree of insulin resistance was measured by homeostasis model assessment of basal insulin resistance (HOMA-IR). Insulin sensitivity was calculated using the composite whole body insulin sensitivity index (ISIcomp) during the oral glucose tolerance test. Insulin receptor-related signaling mediators in soleus muscles of rats were evaluated by immunoprecipitation or immunoblotting. The extract of A. moschatus had a higher level of polyphenolic flavonoids. A. moschatus extract (200 mg/kg per day) displayed the characteristics of rosiglitazone (4 mg/kg per day) in reducing the higher HOMA-IR index as well as elevating ISIcomp in fructose chow-fed rats after a 2-week treatment. Treatment with moschatus extract for 2 weeks increased post-receptor insulin signaling mediated by enhancements in insulin receptor substrate-1-associated phosphatidylinositol 3-kinase step and glucose transporter subtype 4 translocation in insulin-resistant soleus muscles. A. moschatus is therefore proposed as potentially useful adjuvant therapy for patients with insulin resistance and/or the subjects wishing to increase insulin sensitivity.

Pioglitazone metabolic effect in metformin-intolerant obese patients treated with sibutramine

OBJECTIVE

Metformin is the drug of choice to treat obese type 2 diabetes patients because it reduces either insulin-resistance and body weight. We aimed to comparatively test the efficacy and tolerability of pioglitazone and sibutramine in metformin-intolerant obese type 2 diabetic patients treated with sibutramine.

MATERIALS AND METHODS

Five hundred and seventy-six consecutive Caucasian obese type 2 diabetic patients were evaluated during a 12-months period and fifty-two patients were resulted intolerant to metformin at maximum dosage (3,000 mg/day). All intolerant patients to metformin received a treatment with pioglitazone (45 mg/day) and sibutramine (10 mg/day) and they were compared with fifty-three patients treated with metformin (3,000 mg/day) and sibutramine (10 mg/day) for 6 months in a single-blind controlled trial. We assessed body mass index, waist circumference, glycated hemoglobin, Fasting Plasma glucose, postprandial plasma glucose, fasting plasma insulin, postprandial plasma insulin, lipid profile, systolic blood pressure, diastolic blood pressure and heart rate at baseline and after 3, and 6 months.

RESULTS

No body mass index change was observed at 3, and 6 months in pioglitazone + sibutramine group, while a significant reduction of body mass index and waist circumference was observed after 6 months in metformin + sibutramine group (p<0.05). A significant decrease of glycated hemoglobin, Fasting Plasma glucose, postprandial plasma glucose, fasting plasma insulin, postprandial plasma insulin and HOMA index was observed after 3, and 6 months in both groups (p<0.05, and p<0.01, respectively). A significant Tg reduction was present after 6 months (p<0.05) in both groups respect to the baseline values. No systolic blood pressure, diastolic blood pressure and heart rate change was obtained after 3, and 6 months in both groups.

CONCLUSION

Pioglitazone and sibutramine combination appears to be a short-term equally efficacious and well-tolerated therapeutic alternative respect to metformin-intolerant obese type 2 diabetic patients treated with sibutramine.

HbA 1c as a risk factor for heart failure in persons with diabetes: the Atherosclerosis Risk in Communities (ARIC) study

AIMS/HYPOTHESIS

Heart failure (HF) incidence in diabetes in both the presence and absence of CHD is rising. Prospective population-based studies can help describe the relationship between HbA(1c), a measure of glycaemia control, and HF risk.

METHODS

We studied the incidence of HF hospitalisation or death among 1,827 participants in the Atherosclerosis Risk in Communities (ARIC) study with diabetes and no evidence of HF at baseline. Cox proportional hazard models included age, sex, race, education, health insurance status, alcohol consumption, BMI and WHR, and major CHD risk factors (BP level and medications, LDL- and HDL-cholesterol levels, and smoking).

RESULTS

In this population of persons with diabetes, crude HF incidence rates per 1,000 person-years were lower in the absence of CHD (incidence rate 15.5 for CHD-negative vs 56.4 for CHD-positive, p<0.001). The adjusted HR of HF for each 1% higher HbA(1c) was 1.17 (95% CI 1.11-1.25) for the non-CHD group and 1.20 (95% CI 1.04-1.40) for the CHD group. When the analysis was limited to HF cases which occurred in the absence of prevalent or incident CHD (during follow-up) the adjusted HR remained 1.20 (95% CI 1.11-1.29).

CONCLUSIONS/INTERPRETATIONS

These data suggest HbA(1c) is an independent risk factor for incident HF in persons with diabetes with and without CHD. Long-term clinical trials of tight glycaemic control should quantify the impact of different treatment regimens on HF risk reduction.

Type 2 diabetes: the many facets of care

A review of Type 2 diabetes mellitus is presented. Lifestyle recommendations with a focus on currently available medications are discussed. A case study involving a patient with diabetes mellitus and a foot ulcer is discussed in relation to current treatment recommendations.

Myricetin, a naturally occurring flavonol, ameliorates insulin resistance induced by a high-fructose diet in rats

The present study was conducted to explore the effects of myricetin on insulin resistance in rats fed for 6 weeks with a diet containing 60% fructose. Repeated intravenous (i.v.) injection of myricetin (1 mg/kg per injection, 3 times daily) for 14 days was found to significantly decrease the high glucose and triglyceride levels in plasma of fructose chow-fed rats. Also, the higher degree of insulin resistance in fructose chow-fed rats as measured by homeostasis model assessment of basal insulin resistance was significantly decreased by myricetin treatment. Myricetin increased the whole-body insulin sensitivity in fructose chow-fed rats, as evidenced by the marked elevation of composite whole-body insulin sensitivity index during the oral glucose tolerance test. Myricetin was found to reverse the defect in expression of insulin receptor substrate-1 (IRS-1) and the p85 regulatory subunit of phosphatidylinositol 3-kinase (PI 3-kinase) in soleus muscle of fructose chow-fed rats under the basal state, despite the protein expression of insulin receptor (IR). Increased basal phosphorylation of IR and IRS-1 as well as Akt was observed in parallel. The reduced level of insulin action on phosphorylation of IR, IRS-1 and Akt in soleus muscle of fructose chow-fed rats was reversed by myricetin treatment. Furthermore, myricetin treatment improved the defective insulin action on the translocation of glucose transporter subtype 4 (GLUT 4) in insulin-resistant soleus muscle. These findings indicate that myricetin improves insulin sensitivity through the enhancement of insulin action on IRS-1-associated PI 3-kinase and GLUT 4 activity in soleus muscles of animals exhibiting insulin resistance.

Intensive Session: New Approaches to Medical Issues in Long-Term Care

This article, based on a series of presentations at the American Medical Directors Association, briefly highlights new advances in medical areas of interest to long-term care physicians. The areas discussed are heart failure, vitamin D, falls, new treatments for diabetes mellitus, blood pressure measurement, anemia, clinical nutrition, pressure ulcers, Clostridium difficile, insomnia, and antipsychotic therapy.