Severity Grade Assessment Classifications for Both Insulin Resistance Syndrome and Status of Pancreatic Beta Cell Function in Clinical Practice Using Homeostasis Model Assessment Method Indices

Effects of Aqueous Saffron Extract on Glucoregulation as Well as Hepatic Agt and TNF-α Gene Expression in Rats Subjected to Sub-Chronic Stress

Background

Stress and saffron seem to affect glucoregulation mechanisms and insulin resistance in different ways. Impacts of the aqueous saffron extract were investigated on serum glucose levels, serum insulin levels, the homeostatic model assessment of β-cell function (HOMA-B), the homeostatic model assessment of insulin resistance (HOMA-IR), adrenal weight, and hepatic gene expression of angiotensinogen (Agt) and tumor necrosis factor-α (TNF-α) in rats under sub-chronic stress.

Materials and Methods

Forty-two male rats were divided into six groups: control, restraint stress (6h/day for seven days), saffron (30 and 60 mg/kg) treatments for seven days, and post-stress saffron (30 and 60 mg/kg) treatments for seven days. The serum glucose and insulin levels, hepatic gene expressions of Agt and TNF-α, HOMA-IR, HOMA-B, and adrenal gland weight were measured.

Results

One-week recovery following sub-chronic stress led to non-significant hyperglycemia, hyperinsulinemia, and insulin resistance. The hepatic Agt and TNF-α mRNA levels increased significantly in this group. Saffron administration led to enhanced hepatic Agt mRNA in the non-stressed subjects. In addition, serum glucose levels, insulin resistance, and hepatic Agt gene expression significantly increased in stress-saffron groups. The hepatic TNF-α gene expression was reduced only in the stress-saffron 60 group.

Conclusion

Saffron treatment after sub-chronic stress not only did not improve glucose tolerance but also enhanced insulin resistance. It indicated the interaction of saffron and sub-chronic stress to promote renin-angiotensin system activity. In addition, the saffron treatment decreased TNF-α gene expression after sub-chronic stress. The synergistic stimulating effect of saffron and sub-chronic stress on gene expression of hepatic Agt led to insulin resistance and hyperglycemia.

The relationship between vitamin D status and islet function in patients with type 2 diabetes mellitus

BACKGROUND

The aim of the study was to explore the relationship between vitamin D status and islet function in patients with type 2 diabetes mellitus.

METHODS

The participants were recruited from Hebei General Hospital. Basic characteristics and blood indicators were collected after fasting overnight. The data were analyzed statistically using SPSS 22.0. Analysis of variance, a nonparametric test, or a trend Chi-square test was used for the comparisons. The association between 25-hydroxy vitamin D and modified homeostasis model assessment-β was assessed using multivariate ordinal logistic regression.

RESULTS

One hundred seventy-four patients aged 26 to 79 years with type 2 diabetes mellitus were included in this study. Patients with vitamin D deficiency had a lower modified homeostasis model assessment-β level compared with those without vitamin D deficiency. There were differences in body mass index, diabetes course, glycosylated hemoglobin, fasting blood glucose, fasting blood C-peptide, triglyceride, and 25-hydroxy vitamin D among different modified homeostasis model assessment-β groups based upon the tertiles. 25-hydroxy vitamin D, as continuous or categorical variables, was positively related to modified homeostasis model assessment-β whether or not cofounding factors were adjusted.

CONCLUSION

There is an association between increased 25-hydroxy vitamin D levels and improvement in modified homeostasis model assessment-β function in patients with type 2 diabetes mellitus.

TRIAL REGISTRATION

Cross-sectional trails ChiCTR2000029391 , Registration Date: 29/01/2020.

Association Analysis of Insulin Resistance and Osteoporosis Risk in Chinese Patients with T2DM

Background

To explore the relationship between insulin resistance and osteoporosis risk in Chinese patients with type 2 diabetes mellitus (T2DM).

Methods

A total of 234 T2DM patients were retrospectively analyzed, and their lumbar bone mineral density (BMD) and insulin resistance using C-peptide-based homeostasis model of insulin resistance [HOMA-IR (CP)] were assessed. Univariate and multivariable logistic regression methods were used to evaluate the association between HOMA-IR (CP) and osteoporosis, and subgroup analysis was performed on female and male patients.

Results

After fully adjusting the covariates, the association between HOMA-IR (CP) and osteoporosis was only significant in female patients (P = 0.022); the interaction effect with gender was significant (P for interaction <0.05). Curve fitting showed that the relationship between HOMA-IR (CP) and osteoporosis in women was nonlinear. When HOMA-IR (CP) is <4.00, its effect on osteoporosis was not significant (P = 0.474); when HOMA-IR (CP) is >4.00, the risk of osteoporosis increased significantly, with OR = 26.88 (95% CI: 2.75-262.69, P = 0.005). The relationship between insulin resistance and osteoporosis risk in T2DM patients is significantly affected by gender.

Conclusion

The higher the degree of insulin resistance in female patients, the greater the risk of osteoporosis, but the two are not linearly associated.

Vitamin D Status is Independently Associated with Insulin Resistance in Patients with Type 2 Diabetes Mellitus

Purpose

This study aimed to examine whether 25-hydroxyvitamin D (25OHD) levels (an indicator of vitamin D status) are independently associated with insulin resistance (IR) in patients with type 2 diabetes mellitus (T2DM).

Patients and Methods

This was a cross-sectional study. Participants with T2DM were recruited from the Department of Endocrinology in Hebei General Hospital according to inclusion and exclusion criteria. Data on basic characteristics and blood parameters were collected. We used the IR index (20/[fasting C-peptide × fasting plasma glucose]) to evaluate IR. Potential confounding factors were selected from comparisons among different IR index groups of quartiles and were adjusted in different models.

Results

We included 172 subjects (121 men and 51 women) whose mean age was 53.2±10.6 years. Body mass index (BMI), DM course, insulin use, glycated hemoglobin (HbA1c), fasting blood glucose, fasting C-peptide, triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), apolipoprotein A1 (ApoA1), and albumin were differed among different IR-index groups (all P value <0.05). In models 1 and 2, no or some confounding factors were adjusted for, and we found that there was no relationship between 25OHD and the IR index. In model 3, when all confounding factors (DM course, insulin use, BMI, HbA1c, TG, HDL-C, ApoA1, albumin and other bone turnover markers) were adjusted for, the IR index was increased by 5.6% when 25OHD levels increased by 1 ng/mL (odds ratio: 1.056; 95% confidence interval: 1.009, 1.105).

Conclusion

Vitamin D is independently associated with IR in patients with T2DM.