Effect of diabetes and Sorbinil treatment on phospholipid metabolism in rat glomeruli

Alterations of Gut Microbiota and Blood Lipidome in Gestational Diabetes Mellitus With Hyperlipidemia

Clinical gestational diabetes mellitus (GDM) is frequently associated with hyperlipidemia comorbidity. Altered human gut microbiome has been linked to GDM and hyperlipidemia, respectively but not the comorbid condition. We hypothesize that the occurrence of hyperlipidemia with GDM may be characterized by distinguishable gut microbiome and blood metabolomic patterns. We presented comprehensive microbiomic coupled with lipidomics analyses to characterize gut microbiota and lipometabolism of plasma samples in women with GDM only, hyperlipidemia only and those with diabetes plus hyperlipidemia, and to explore association of the gut microbiota composition with blood lipid profiles and clinical parameters of gestational diabetes with or without commodity. We found that the relative abundance of bacterial taxa Streptococcus, Faecalibacterium, Veillonella, Prevotella, Haemophilus and Actinomyces was significantly higher in diabetes plus hyperlipidemia cohorts. Moreover, several bacteria were correlated with fasting plasma glucose and blood lipid levels of the participants with GDM and hyperlipidemia. The altered plasma lipidome in subjects with diabetes plus hyperlipidemia suggested that characteristic blood lipid profiles were associated with the pathogenesis of gestational diabetes plus hyperlipidemia. Collectively, this study provides insights on changes in fecal microbiota and plasma lipidome to predict and characterize the development of gestational diabetes with lipid metabolic abnormality.

Phospholipidomic identification of potential plasma biomarkers associated with type 2 diabetes mellitus and diabetic nephropathy

Type 2 diabetes mellitus (T2DM) and its attendant complications, such as diabetic nephropathy (DN), impose a significant societal and economic burden. The investigation of discovering potential biomarkers for T2DM and DN will facilitate the prediction and prevention of diabetes. Phospholipids (PLs) and their metabolisms are closely allied to nosogenesis and aggravation of T2DM and DN. The aim of this study is to characterize the human plasma phospholipids in T2DM and DN to identify potential biomarkers of T2DM and DN. Normal phase liquid chromatography coupled with time of flight mass spectrometry (NPLC-TOF/MS) was applied to the plasma phospholipids metabolic profiling of T2DM and DN. The plasma samples from control (n=30), T2DM subjects (n=30), and DN subjects (n=52) were collected and analyzed. The significant difference in metabolic profiling was observed between healthy control group and DM group as well as between control group and DN group by the help of partial least squares discriminant analysis (PLS-DA). PLS-DA and one-way analysis of variance (ANOVA) were successfully used to screen out potential biomarkers from complex mass spectrometry data. The identification of molecular components of potential biomarkers was performed on Ion trap-MS/MS. An external standard method was applied to quantitative analysis of potential biomarkers. As a result, 18 compounds in 7 PL classes with significant regulation in patients compared with healthy controls were regarded as potential biomarkers for T2DM or DN. Among them, 3 DM-specific biomarkers, 8 DN-specific biomarkers and 7 common biomarkers to DM and DN were identified. Ultimately, 2 novel biomarkers, i.e., PI C18:0/22:6 and SM dC18:0/20:2, can be used to discriminate healthy individuals, T2DM cases and DN cases from each other group.

Effects of Shendan Jianyi Capsule on aldose reductase activity of kidney in diabetic rats

OBJECTIVE

To evaluate the effects of Shendan Jianyi Capsule (SDJYC) on aldose reductase (AR) activity of the kidney in diabetic rats and the significance of prevention and treatment of diabetic nephropathy with Chinese natural herbs.

METHODS

Diabetic Wistar rats were treated with SDJYC and sorbinil respectively, and the AR activity in kidney, urine protein and the activity of Na(+)-K(+)-ATPase were tested.

RESULTS

The AR activity in diabetic rats was decreased obviously after being treated with sorbinil or SDJYC. The activity of Na(+)-K(+)-ATPase in diabetic rats decreased obviously at the end of the eighth week, and increased after being treated with sorbinil and SDJYC. There was no difference between two treated groups after the treatment. It demonstrated that the inhibition of AR activity could improve the activity of Na(+)-K(+)-ATPase and SDJYC had the same effect.

CONCLUSIONS

SDJYC exerts effects by inhibiting the activity of AR.

Upregulation of D-myo-inositol transport in diabetic rat glomerular cells

In the streptozotocin (STZ)-treated diabetic rat, reduced glomerular arteriolar resistance leads to raised intraglomerular pressure. Because vasoconstrictor hormones, such as angiotensin II, stimulate arteriolar smooth muscle and mesangial cell contraction via the D-myo-inositol (MI)-dependent transmembrane signaling pathway, in diabetes extracellular D-glucose may inhibit MI transport causing MI depletion, reduced signaling, and hypocontractility. Therefore we studied the regulation of Na-dependent MI transport in the intact cells (mesangial and endothelial) of isolated glomeruli from STZ rats after 2 wk of diabetes, with and without insulin, compared with controls. Specific [3H]MI uptake per milligram glomerular protein (10-150 min, 37 degrees C) was observed in the presence of 0, 5.5, and 30 mM D-glucose using L-[14C]glucose as a marker of nonspecific uptake. D-Glucose competitively inhibited Na-dependent MI transport (maximum velocity) into diabetic and normal glomerular cells. At 5.5 mM D-glucose, MI uptake by diabetic non-insulin-treated glomeruli was increased to 191 +/- 14% (SE) above normal glomeruli. Insulin treatment resulted in less upregulation (116 +/- 11%) of normal MI transport. High glucose concentration did not alter the rate of [3H]MI efflux from preloaded glomerular cells. To determine whether diabetes alters available substrate for transmembrane signaling, after incubation for 120 min, the incorporation of [3H]MI into cellular membrane phosphoinositides and soluble D-myo-inositol phosphates of isolated diabetic and control glomerular cells was compared. Diabetic glomerular cells displayed a significant increase (P less than 0.005) in [3H]MI incorporation into these fractions compared with controls.