Assessment of insulin sensitivity and secretion in patients with fibrocalculous pancreatic diabetes

Hydrogen sulfide ameliorates hypertension and vascular dysfunction induced by insulin resistance in rats by reducing oxidative stress and activating eNOS

Hydrogen sulfide (H2S) is a gasotransmitter implied in metabolic diseases, insulin resistance, obesity, and type 2 Diabetes Mellitus. This study aimed to determine the effect of chronic administration of sodium hydrosulfide (NaHS; inorganic H2S donor), L-Cysteine (L-Cys; substrate of H2S producing enzymes) and DL-Propargylglycine (DL-PAG; cystathionine-gamma-lyase inhibitor) on the vascular dysfunction induced by insulin resistance in rat thoracic aorta. For this purpose, 72 animals were divided into two main sets that received: 1) tap water (control group; n = 12); and 2) fructose 15% w/v in drinking water [insulin resistance group (IR); n = 60] for 20 weeks. After 16 weeks, the group 2 was divided into five subgroups (n = 12 each), which received daily i. p. injections during 4 weeks of: 1) non-treatment (control); 2) vehicle (phosphate buffer saline; PBS, 1 ml/kg); 3) NaHS (5.6 mg/kg); 4) L-Cys (300 mg/kg); and (5) DL-PAG (10 mg/kg). Hemodynamic variables, metabolic variables, vascular function, ROS levels and the expression of p-eNOS and eNOS were determined. IR induced: 1) hyperinsulinemia; 2) increased HOMA-index; 3) decreased Matsuda index; 4) hypertension, vascular dysfunction, increased ROS levels; 5) increased iNOS, and 6) decreased CSE, p-eNOS and eNOS expression. Furthermore, IR did not affect contractile responses to norepinephrine. Interestingly, NaHS and L-Cys treatment, reversed IR-induced impairments and DL-PAG treatment decreased and increased the HOMA and Matsuda index, respectively. Taken together, these results suggest that NaHS and L-Cys decrease the metabolic and vascular alterations induced by insulin resistance by reducing oxidative stress and activating eNOS. Thus, hydrogen sulfide may have a therapeutic application.

Efficacy of intermittent short-term use of a real-time continuous glucose monitoring system in non-insulin-treated patients with type 2 diabetes: A randomized controlled trial

AIM

To evaluate the efficacy of intermittent short-term use of a real-time continuous glucose monitoring (RT-CGM) system in non-insulin-treated patients with type 2 diabetes (T2D) uncontrolled with oral antidiabetic drugs (OADs).

MATERIALS AND METHODS

In this multicentre, randomized prospective study, 61 participants were randomly assigned to treatment group 1 (one session of RT-CGM), treatment group 2 (two sessions of RT-CGM with a 3-month interval between sessions) and a control group. All participants used blinded continuous glucose monitoring for up to 6 days with education before randomization, and RT-CGM was additionally applied for 1 week in the intervention groups. The primary outcome was change in HbA1c at 6 months.

RESULTS

Among 61 participants, 48 subjects completed the study (baseline HbA1c 8.2% ± 0.5%). At 3 months, a significant HbA1c reduction was observed in treatment group 1 (adjusted difference = -0.60%, P = .044) and treatment group 2 (adjusted difference = -0.64%, P = .014) compared with the control group. However, at 6 months, only treatment group 2 achieved a significant HbA1c reduction (adjusted difference = -0.68%, P = .018). Especially in the treatment groups, patients performing self-monitoring of blood glucose (SMBG) at least 1.5 times/day showed a significant HbA1c improvement, at both 3 and 6 months, but those performing SMBG less than 1.5 times/day showed no significant improvement.

CONCLUSIONS

In non-insulin-treated patients with T2D uncontrolled with OADs, intermittent short-term use of RT-CGM was an effective method for glucose control, especially in those performing SMBG frequently.

Cabral P, Guerreiro V, Lourenço R, Meira P, Salazar D, Ferreira MJ, Pedro J, Barkoudah E, Sande A, Lau E, B. Souto S, Preto J, Freitas P, Carvalho D. Beta Cell Function as a Baseline Predictor of Weight Loss After Bariatric Surgery

BACKGROUND

Obesity is a multifactorial disease, which is strongly associated to other metabolic disorders. Bariatric surgery is the most effective treatment of morbid obesity. The role of beta cell function in weight loss after bariatric surgery is uncertain.

AIM

To evaluate the association between beta cell function and percentage of total body weight loss (TBWL%) 1, 2, 3, and 4 years after bariatric surgery in patients with morbid obesity.

METHODS

Retrospective longitudinal study in patients with morbid obesity followed in our center between January 2010 and July 2018. Patients were excluded if they had diabetes at baseline or missing data on the needed parameters. We evaluated baseline Homeostatic Model Assessment of IR, Homeostatic Model Assessment of β-cell function (HOMA-beta), Quantitative Insulin Sensitivity Check Index, and Matsuda and DeFronzo index, and TBWL% at years 1 to 4. Linear regression models were used to evaluate the association of indexes of insulin resistance with TBWL% (unadjusted and adjusted for age, sex, BMI, and type of surgery).

RESULTS

There were 1,561 patients included in this analysis. HOMA-beta was negatively associated with TBWL% at second, third, and fourth years post-surgery (β = -1.04 [-1.82 to -0.26], p<0.01; β = -1.16 [-2.13 to -0.19], p=0.02; β = -1.29 [-2.64 to 0.06], p=0.061, respectively). This was not observed in the first year post-surgery nor for the other indexes. Glycemia at baseline was positively associated to EWL% at second and third years post-surgery.

CONCLUSION

β-cell function at baseline seems to be associated to long-term weight loss, explicitly after the first year post bariatric surgery. This might be a helpful predictor of weight loss in clinical practice.

Pathological Mechanisms in Diabetes of the Exocrine Pancreas: What's Known and What's to Know

The clinical significance of diabetes arising in the setting of pancreatic disease (also known as diabetes of the exocrine pancreas, DEP) has drawn more attention in recent years. However, significant improvements still need to be made in the recognition, diagnosis and treatment of the disorder, and in the knowledge of the pathological mechanisms. The clinical course of DEP is different from type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). DEP develops in patients with previous existing exocrine pancreatic disorders which damage both exocrine and endocrine parts of pancreas, and lead to pancreas exocrine insufficiency (PEI) and malnutrition. Therefore, damage in various exocrine and endocrine cell types participating in glucose metabolism regulation likely contribute to the development of DEP. Due to the limited amount of clinical and experimental studies, the pathological mechanism of DEP is poorly defined. In fact, it still not entirely clear whether DEP represents a distinct pathologic entity or is a form of T2DM arising when β cell failure is accelerated by pancreatic disease. In this review, we include findings from related studies in T1DM and T2DM to highlight potential pathological mechanisms involved in initiation and progression of DEP, and to provide directions for future research studies.

Non-tropical fibrocalculous pancreatic diabetes: case reports and review of recent literature

Background

Fibrocalculous pancreatic diabetes (FCPD), an uncommon form of secondary diabetes, is caused by chronic nonalcoholic calcific pancreatitis and primarily occurs in tropical countries.

Objective

To present our first-hand experiences in the diagnosis and management of FCPD in two patients from a non-tropical location.

Case report

Two male Chinese patients (29 and 32 years old) presented with poor insulin function, negative islet cell and glutamate decarboxylase antibodies, and no spontaneous ketosis or abdominal pain. A careful clinical assessment was made and the results were correlated with laboratory findings. Abdominal ultrasound and computed tomography scans further revealed pancreatic calcification, calculi, and pancreatic duct dilation. Differential diagnosis confirmed FCPD and excluded the potential misdiagnosis of type 2 diabetes mellitus. FCPD in these patients was managed with insulin and symptomatic treatment with close monitoring. At the time of submission of this report, the first patient was stable at his last follow-up, but the second had been re-hospitalized for worsening symptoms.

Conclusion

Early differential diagnosis of FCPD based on clinical examination and biochemical and radiological investigations, in tandem with insulin therapy, can help manage FCPD effectively.