Prediabetes: how pathophysiology drives potential intervention on a subclinical disease with feared clinical consequences

Vitamin D supplementation alleviates insulin resistance in prediabetic rats by modifying IRS-1 and PPARγ/NF-κB expressions

Background

Prediabetes is a condition of intermediate hyperglycemia that may progress to type 2 diabetes. Vitamin D deficiency has been frequently linked to insulin resistance and diabetes. The study aimed to investigate the role of D supplementation and its possible mechanism of action on insulin resistance in prediabetic rats.

Method

The study was conducted on 24 male Wistar rats that were randomly divided into 6 rats as healthy controls and 18 prediabetic rats. Prediabetic rats were induced with a high-fat and high-glucose diet (HFD-G) combined with a low dose of streptozotocin. Rats with the prediabetic condition were then randomized into three groups of 12-week treatment: one group that received no treatment, one that received vitamin D3 at 100 IU/kg BW, and one group that received vitamin D3 at 1000 IU/kg BW. The high-fat and high-glucose diets were continuously given throughout the twelve weeks of treatment. At the end of the supplementation period, glucose control parameters, inflammatory markers, and the expressions of IRS1, PPARγ, NF-κB, and IRS1 were measured.

Results

Vitamin D3 dose-dependently improves glucose control parameters, as shown by the reduction of fasting blood glucose (FBG), oral glucose tolerance test (OGTT), glycated albumin, insulin levels, and markers of insulin resistance (HOMA-IR). Upon histological analysis, vitamin D supplementation resulted in a reduction of the islet of Langerhans degeneration. Vitamin D also enhanced the ratio of IL-6/IL-10, reduced IRS1 phosphorylation at Ser307, increased expression of PPAR gamma, and reduced phosphorylation of NF-KB p65 at Ser536.

Conclusion

Vitamin D supplementation reduces insulin resistance in prediabetic rats. The reduction might be due to the effects of vitamin D on IRS, PPARγ, and NF-κB expression.

Predicting the response to SGLT-2 inhibitors as add-on therapy to multiple day injection insulin with glycated albumin: a pilot study

BACKGROUND

Achieving optimal glycemic targets is the main therapeutic goal in patients with type 2 diabetes (T2D) mellitus. HbA1c is the reference biomarker for monitoring glycemic control; however, in specific conditions affecting erythrocyte turnover or in patients on multiple daily injection (MDI) insulin regimens, the determination of glycated albumin (GA) may be preferable. Sodium-glucose cotransporter-2 (SGLT-2) inhibitors represent a novel class of antidiabetic drugs that lower plasma glucose concentrations quickly, with insulin-independent mechanisms. Herein, we explored the role of GA in predicting the short-term response to SGLT-2 inhibitors as add-on to MDI insulin.

METHODS

Sixteen patients with long-standing, poorly controlled T2D on MDI insulin starting an SGLT-2 inhibitor were subjected to plasma GA and HbA1c measurements at 30 days intervals for up to 3 months in order to examine the temporal changes of these glycemic biomarkers.

RESULTS

At the end of the study, grossly coincident with the life span of erythrocytes, a significant decrease in median HbA1c was observed, (from 8.7 [range: 8.2-9.3%] at baseline to 7.2 [range: 7.0-7.9%]), with the advantage of less insulin dose requirements. However, significant, and incremental reductions in median GA determinations could be already evident after 30 days (-3.5 [range: -7.5, -2.5%]) and 60 days (-6.4 [range: -10.5, -4.7%]) from the start of SGLT-2 inhibitor treatment and persisted for up to 3 months (-8.6 [range: -12.1, 6.1%]). The decrements of HbA1c observed at the 3-month visit were highly correlated with the concurrent absolute reductions of plasma GA (ρ=0.550, P=0.027), whereas a borderline significance could be demonstrated with reference to reductions in plasma GA at 30 and 60 days.

CONCLUSIONS

Although limited by the small number of participants, these preliminary findings suggest that GA, rather than HbA1c, could represent a useful and reliable biomarker in T2D to monitor the early glucose-lowering effects of antidiabetic drugs with rapid onset of action, such as SGLT-2 inhibitors and MDI insulin.

Evaluation of Turkey diabetes self-management education in geriatrics with type 2 diabetes

BACKGROUND

This study was conducted to evaluate the diabetes education efficiency of individuals over 65 years old in Turkey, which has the highest prevalence of diabetes in Europe.

METHODS

We retrospectively evaluated 320 patients who attended Turkey diabetes self-management group education program (TDSMEP) between 2016 and 2020 in a secondary hospital. Participants who have been followed up for a maximum of 9 months are grouped as over 65 years old and under.

RESULTS

Of the 320 patients, 114 formed the geriatric group and 206 the non-geriatric group. After the training, the number of patients who had HbA1c ≤7% increased significantly in both the geriatric (28.1%-45.6%) and non-geriatric (19.9%-42.2%) (p = 0.001) groups. After the training, similar HbA1c goals were achieved in the geriatric and non-geriatric groups. The most significant HbA1c decrease was observed at the 3rd month of follow-up and remained stable until the 9th month. In logistic regression analysis, the factors affecting HbA1c failure (HbA1c >7%) after training in the geriatric group were long diabetes duration (OR = 1.07, 95% CI = 1.02-1.13, p = 0.01), high basal HbA1c levels (OR = 1.31, 95% CI = 1.03-1.67, p = 0.03), and low education level (OR = 3.88, 95% CI = 1.54-9.76, p = 0.001).

CONCLUSIONS

This is the first study to evaluate the effectiveness of TDSMEP for geriatric individuals whose HbA1c ≤7% increased from 28% to 45.6% during follow-up after the training. TDSMEP is recommended for all adult age groups, regardless of age range.