Pharmacological management of type 2 diabetes: the potential of incretin-based therapies

Management guidelines recommend metformin as the first-line therapy for most patients with type 2 diabetes uncontrolled by diet and exercise. Efficacy with metformin therapy is usually of limited duration, which necessitates the early introduction of one or two additional oral agents or the initiation of injections, glucagon-like peptide-1 (GLP-1) agonists or insulin. Although safe and effective, metformin monotherapy has been associated with gastrointestinal side effects (≈20% of treated patients in randomized studies) and is contraindicated in patients with renal insufficiency or severe liver disease. Patients treated with a sulphonylurea are at increased risk for hypoglycaemia and moderate weight gain, whereas those receiving a thiazolidinedione are subject to an increased risk of weight gain, oedema, heart failure or fracture. Weight gain and hypoglycaemia are associated with insulin use. Thus, there is an unmet need for a safe and efficacious add-on agent after initial-therapy failure. Evidence suggests that incretin-based agents, such as GLP-1 receptor agonists and dipeptidyl peptidase-4 inhibitors, can successfully achieve glycaemic targets and potentially provide cardiovascular and β-cell-function benefits. This review will examine current approaches for treating type 2 diabetes and discuss the place of incretin therapies, mainly GLP-1 agonists, in the type 2 diabetes treatment spectrum.

The farnesoid X receptor (FXR) as a new target in non-alcoholic steatohepatitis

The farnesoid X receptor (FXR) is a member of the nuclear receptor superfamily that is mainly expressed in liver, intestine, kidney and adipose tissue. On activation by bile acids, FXR regulates a wide variety of target genes that are critically involved in the control of bile acid, lipid and glucose homeostasis. Thus, FXR appears to be a promising target for the treatment of non-alcoholic steatohepatitis (NASH). Notably, FXR activation inhibits hepatic de novo lipogenesis, increases insulin sensitivity and protects hepatocytes against bile acid-induced cytotoxicity. More recent data also indicate a critical role of FXR in liver regeneration and hepatocarcinogenesis. For this reason, the development of FXR agonists and/or modulators (SBARMs) may prove to be clinically useful for treating NASH. While preclinical studies in rodents support this hypothesis, clinical studies are still warranted in humans.

Fulminant type 1 diabetes in Caucasians: A report of three cases

CONTEXT

Fulminant type 1 diabetes is a new clinical entity in which the process of beta-cell destruction, and the subsequent progression of hyperglycaemia and ketoacidosis, are extremely rapid. Until now, this subtype of type 1 diabetes has only been reported in the Asian population, especially Japanese and Koreans.

CASES

We report here on three cases of fulminant type 1 diabetes in Caucasian French women. Both the clinical and biological characteristics of these patients are similar to those reported in Japanese studies. Notably, all patients experienced severe ketoacidosis (pH<7.1) that occurred abruptly after the onset of hyperglycaemic symptoms (<6 days), with near-normal HbA(1c) values at diagnosis (5.6, 6.4 and 6.8%). Patients were treated in the intensive care unit with basal-bolus insulin therapy with no remission of their diabetes; pancreatic islet-related autoantibodies were all negative. Fasting C-peptide levels were undetectable, suggesting complete destruction of pancreatic beta-cells. HLA phenotyping of these Caucasian patients did not find the specific HLA haplotype (DRB1*0405-DQB1*0401) previously found to be linked to fulminant type 1 diabetes in Japanese patients.

CONCLUSION

These are the first cases of fulminant type 1 diabetes reported in Caucasians. These cases reveal new perspectives as regards the worldwide distribution of this intriguing clinical entity.

[Cutaneous metastases from follicular thyroid cancer]

BACKGROUND

Cutaneous metastases from differentiated thyroid carcinoma are rare: only 41 cases have been reported in the literature.

CASE REPORT

A 57-year-old woman underwent total thyroidectomy for a poor differentiated follicular thyroid carcinoma, with involvement of sternum and pulmonary metastases. Despite iodine-131 ablative therapy (> 1 Ci) she developed a skin metastasis of the scalp 9 years after the initial surgery. She died of widely metastatic thyroid carcinoma.

DISCUSSION

Follicular carcinoma has a greater preponderance than papillary carcinoma for cutaneous metastases. The majority of skin metastases are localized to the head and neck. The development of a cutaneous metastasis is commonly associated with metastasis to other distant tissues and is followed by a deteriorating course and eventual death resulting from malignancy.

Angiographic characteristics of coronary artery disease in diabetic patients compared with matched non-diabetic subjects

The aim of this study was to assess the extent and the severity of coronary artery disease (CAD) in diabetic patients. Angiographic findings were retrospectively analysed in 50 diabetic and in 50 non-diabetic patients, matched for age and sex, undergoing coronary angiography for evaluation of clinically CAD or silent ischaemia. Baseline characteristics did not show any increase of cardiovascular risk in diabetics compared to the non-diabetic group. Diabetic patients present less chest pain and more electric abnormalities, reflecting CAD specificity for diabetic patients. Angiograms of the coronary tree were divided into 13 segments and two experienced angiographers have developed a methodic analysis of selected coronary segment stenosis. The number of significant coronary artery stenosis (> or = 50%) per patient was higher in diabetic than in non-diabetic subjects (5.06+/-2.16 vs 2.40+/-1.97, p < 0.05). Diabetics had also more left main CAD (7/50 vs 1/50,p < 0.05). Though we did not find at any time statistical difference for multivessel, distal or diffuse CAD between the two groups, nevertheless there are more diffuse and distal lesions of the diabetic coronary artery trees. This debate is not closed, there is always controversy concerning whether the angiographic findings in diabetic or non-diabetic patients are different. But these results corroborate the hypothesis of a greater severity of angiographic proven CAD in diabetic than in non-diabetic patients, especially in the left main coronary artery.

Assessment of gastric neuropathy using electrogastrography in asymptomatic diabetic patients. Correlation with cardiac autonomic neuropathy

This study assessed gastric neuropathy in type 1 diabetes mellitus and its relationships with cardiac autonomic neuropathy. Fifty-four asymptomatic type 1 patients (43 +/- 12 years) and 15 healthy subjects participated in the study. Cutaneous electrogastrography (EGG) was recorded for 4 h before, during, and 4 h after the ingestion of a standard meal. EGG frequency was divided into three bands: bradygastria [< 2 cpm), normal (2-4 cpm) and tachygastria (4-10 cpm)]. Assessment of diabetic autonomic neuropathy was based on Ewing tests and time and frequency domain indexes, which were analyzed from 24-h continuous ECG recordings. Tachygastria was significantly more common in diabetic patients than in controls throughout the recording period (38 +/- 5 vs 23 +/- 11.8%, p < 0.001), before (37 +/- 6 vs 26.5 +/- 8.9%, p < 0.001), during (41 +/- 7.8 vs 23 +/- 10.5%, p < 0.001) and after the meal (37 +/- 6.9 vs 29 +/- 9.8%, p < 0.001). The percentage of dominant frequency in the normal range was significantly lower in diabetic patients than controls (49 +/- 6 vs 63.3 +/- 11.1%, p < 0.001). Tachygastria was correlated with duration of diabetes (r = 0.234, p < 0.05), but not with glycaemic control. Abnormalities in gastric myoelectrical activity were not correlated with Ewing tests or time and frequency domain indexes.