Efficacy of switching from premixed insulin to insulin glargine regimen in Type 2 diabetes mellitus patients with different islet functions

Predictors of HbA1c reduction and hypoglycemia in type 2 diabetes mellitus individuals switching from premixed to basal insulin: an exploratory analysis of optimization study

OBJECTIVE

To identify population with type 2 diabetes mellitus (T2DM) who are more likely to benefit from switching to basal insulin (BI) treatment from premixed insulin.

METHODS

This secondary analysis included data from a previously published study (Optimization: NCT00693771) which was a single-arm, multicenter, 16 weeks, phase IV study. The analysis included participants with T2DM inadequately controlled with premixed insulin plus oral hypoglycemic drugs (OADs) who switched to BI plus OADs.

RESULTS

Among the 297 participants included for analysis, subjects with fasting C-peptide (FCP)>1.2 nmol/L group showed a trend for greater reduction in HbA1c [Least square mean difference (LSMD), -0.59; 95% confidence interval (CI), -0.98 to -0.21; p = 0.003] and FPG (LSMD, -1.36; 95% CI, -2.20 to -0.53; p = 0.002) than those with FCP ≤ 0.4 nmol/L. The baseline insulin glargine 100 U/mL (Gla-100) dose increased significantly in 0.4 to ≤ 1.2 nmol/L group with LS mean difference (SE) of 0.16 (0.01) U/kg/day (p = 0.008) compared to FCP ≤ 0.4 nmol/L group. When combined with Diabetes Treatment Satisfaction Questionnaire (DTSQ) score, participants with a C-peptide level of 0.4 to ≤1.2 nmol/L (OR, 4.05; 95% CI, 1.08 to 15.22; p = 0.039) had significantly higher odds of achieving HbA1c <7%. The number of participants experiencing documented symptomatic hypoglycaemia (≤3.9 mmol/L) was higher in the FCP ≤0.4 nmol/L group compared to those in 0.4 to ≤1.2 nmol/L FCP group at any time of the day (31.6 vs. 17.1%) and during night (00:00 ∼ 05:59) (17.1 vs. 7.5%).

CONCLUSION

The findings from this study proposed that FCP is an important biomarker to identify T2DM participants who experience improved glucose control without compromising on hypoglycemia levels during switch from premixed insulin to BI. Participants especially with FCP levels >1.2 nmol/L may respond better in terms of HbA1c reduction without increased hypoglycemia risk compared to those with lower FCP values.

Dihydromyricetin improves type 2 diabetes-induced cognitive impairment via suppressing oxidative stress and enhancing brain-derived neurotrophic factor-mediated neuroprotection in mice

Type 2 diabetes mellitus (T2DM) leads to cognitive impairment (CI), but there have been no effective pharmacotherapies or drugs for cognitive dysfunction in T2DM. Dihydromyricetin (DHM) is a natural flavonoid compound extracted from the leaves of Ampelopsis grossedentata and has various pharmacological effects including anti-oxidant and anti-diabetes. Thus, we investigated the effects of DHM on CI in T2DM mouse model and its possible mechanism. To induce T2DM, mice were fed with high-sugar and high-fat diet for 8 weeks, followed by a low dose streptozotocin (STZ) administration. After the successful induction of T2DM mouse model, mice were treated respectively with equal volume of saline (T2DM group), 125 mg/kg/d DHM (L-DHM group), or 250 mg/kg/d DHM (H-DHM group). After 16 weeks of DHM administration, the body weight (BW), fasting blood glucose, blood lipids, intraperitoneal glucose tolerance (IPGT), and cognitive function were determined. Then, alterations in the expressions of oxidative stress markers and brain-derived neurotrophic factor (BDNF) in the hippocampus were investigated. Our findings demonstrated that DHM could significantly ameliorate CI and reverse aberrant glucose and lipid metabolism in T2DM mice, likely through the suppression of oxidative stress and enhancement of BDNF-mediated neuroprotection. In conclusion, our results suggest that DHM is a promising candidate for the treatment of T2DM-induced cognitive dysfunction.

Naringin ameliorates cognitive deficits via oxidative stress, proinflammatory factors and the PPARγ signaling pathway in a type 2 diabetic rat model

Naringenin is a flavonoid polyphenolic compound, which facilitates the removal of free radicals, oxidative stress and inflammation. The present study aimed to obtain a better understanding of the effects of curcumin on the regulation of diabetes‑associated cognitive decline, and its underlying mechanisms. An experimental diabetes mellitus (DM) rat model was induced by streptozoticin (50 mg/kg). Following treatment with naringin (100 and 200 mg/kg) for 16 weeks, the body weight and blood glucose levels of the DM rats were measured. A morris water maze test was used to analyze the effects of naringin on the cognitive deficit of the DM rats. The levels of oxidative stress, proinflammatory factors, caspase‑3 and caspase‑9, and the protein expression of peroxisome proliferator‑activated receptor γ (PPARγ) were quantified in the DM rats using a commercially‑available kit and western blot assay, respectively. In addition, a GW9662 PPARγ inhibitor (0.3 mg/kg) was administered to the DM rats to determine whether PPARγ affected the effects of naringin on the cognitive deficit of the DM rats. The results demonstrated that naringin increased the body weight, blood glucose levels, and cognitive deficits of the DM rats. The levels of oxidative stress and proinflammatory factors in the naringin‑treated rats were significantly lower, compared with those of the DM rats. In addition, naringin activated the protein expression of PPARγ, and administration of the PPARγ inhibitor decreased the protein expression of PPARγ, and attenuated the effects of naringin on cognitive deficit. The results also demonstrated that naringin decreased the expression levels of caspase‑3 and caspase‑9 in the DM rats. These results suggested that naringin ameliorated cognitive deficits via oxidative stress, proinflammatory factors and the PPARγ signaling pathway in the type 2 diabetic rat model. Furthermore, oxidative stress, proinflammatory factors and PPARγ signaling may be involved in mediating these effects.