Erythrocyte glucose-6-phosphate dehydrogenase activity and risk of gestational diabetes

Association of serum kynurenine/tryptophan ratio with poor glycemic control in patients with type2 diabetes

Purpose

The role of indoleamine 2,3-dioxygenase (IDO) has been shown in insulin resistance and metabolic syndrome. The present study aimed to measure serum IDO activity in patients with type 2 diabetes (T2DM) and to determine its association with glycemic control, oxidative stress, and insulin resistance.

Methods

Seventy-four patients with T2DM and 74 healthy subjects were selected to participate in this study. Fasting serum biochemical parameters including fasting blood sugar (FBS), HbA1c, insulin, uric acid, albumin, tryptophan, kynurenine, and total antioxidant capacity (TAC) were measured. HOMA-IR, QUICKI, and HOMA-B were calculated using serum FBS and insulin values. IDO activity was estimated using kynurenine/tryptophan ratio (KTR). Data were analyzed using SPSS software (Version 15) and p < 0.05 was considered as a significant difference.

Results

The findings showed higher levels of FBS, HbA1c, HOMA-IR, and KTR in the patients compared to the controls. TAC and HOMA-B were significantly lowered in the T2DM patients compared to controls. KTR was significantly correlated with the level of HbA1c, and T2DM patients with poor glycemic control (HbA1c ≤ 8) had significantly higher level of KTR. HOMA-B was significantly correlated with serum tryptophan and inversely correlated with HbA1c.

Conclusion

Serum KTR is increased in T2DM patients with poor glycemic control. Potential clinical implications and possible pathogenic roles of IDO in T2DM development should be further elucidated.

The effects of iron overload, insulin resistance and oxidative stress on metabolic disorders in patients with β- thalassemia major

Background

Serum lipids and glycemic dysregulation are the known characteristics of β- thalassemia major (β-TM). Here, we evaluated the association of these disorders with insulin resistance (IR), oxidative stress and serum ferritin values in patients with β-TM.

Methods

This case-control study was performed in thalassemia unite of Darab Hospital (Darab, Fars province, Iran) from December 2016 to December 2017. Forty-eight patients with β-TM and 33 healthy individuals were enrolled. Serum fasting blood sugar (FBS), insulin, total cholesterol (TC), triglyceride (TG), high density lipoprotein (HDL), low density lipoprotein (LDL), ischemia modified albumin (IMA), and ferritin were measured. The values of HOMA-IR, LDL: TG ratio, atherogenic index (AI), atherogenic index of plasma (AIP), and coronary risk index (CRI) were calculated.

Results

The level of serum ferritin, IMA, FBS, TG, AIP, LDL: TG ratio, and the prevalence of IR (HOMA-IR < 3.8) were significantly higher while TC, LDL-C, HDL-C, and AI were significantly lower in the patients compared to the control group. In patient with β-TM, serum ferritin revealed to have a positive association with serum insulin, HOMA-IR, AI, and CRI levels while serum IMA showed positive association with TG and AIP and inverse association with hypocholesterolemia. HOMA-IR had positive correlation with HDL levels.

Conclusions

Oxidative stress and iron overload are predictors of serum glycemic and lipid dysregulation, suggesting possible beneficial effect of antioxidants and efficient iron chelating therapy in reducing the risk of metabolic disorders in β- thalassemia.