Serum sialic acid changes in type 2 diabetic patients on metformin or rosiglitazone treatment

Cell Membrane Sialome: Sialic Acids as Therapeutic Targets and Regulators of Drug Resistance in Human Cancer Management

A cellular sialome is a physiologically active and dynamically changing component of the cell membrane. Sialylation plays a crucial role in tumor progression, and alterations in cellular sialylation patterns have been described as modulators of chemotherapy effectiveness. However, the precise mechanisms through which altered sialylation contributes to drug resistance in cancer are not yet fully understood. This review focuses on the intricate interplay between sialylation and cancer treatment. It presents the role of sialic acids in modulating cell-cell interactions, the extracellular matrix (ECM), and the immunosuppressive processes within the context of cancer. The issue of drug resistance is also discussed, and the mechanisms that involve transporters, the tumor microenvironment, and metabolism are analyzed. The review explores drugs and therapeutic approaches that may induce modifications in sialylation processes with a primary focus on their impact on sialyltransferases or sialidases. Despite advancements in cellular glycobiology and glycoengineering, an interdisciplinary effort is required to decipher and comprehend the biological characteristics and consequences of altered sialylation. Additionally, understanding the modulatory role of sialoglycans in drug sensitivity is crucial to applying this knowledge in clinical practice for the benefit of cancer patients.

Elevated Serum Sialic Acid Levels May be Associated With Diabetes Retinopathy: A Cross-Sectional Study in Ghana

This study determined the association between serum sialic acid (SSA) and metabolic risk factors in Ghanaian Type 2 diabetes (T2DM) with and without micro vascular complications. This cross-sectional study recruited 150 T2DM out-patients visiting the diabetic Clinic at the Tema General Hospital, Ghana. Fasting blood samples were collected and analyzed for Total Cholesterol (TC), Triglyceride (TG), Low Density Lipoprotein Cholesterol (LDL-C), High Density Lipoprotein Cholesterol (HDL-C), Fasting Plasma Glucose (FPG), Glycated Haemoglobin (HbA1c), SSA and C-Reactive Protein. SSA levels were significantly higher in diabetics with retinopathy (210.12 ± 85.09mg/dl) compared with those with nephropathy and those without complication (p-value= 0.005). Body adiposity index (BAI) (r= -0.419, p-value = 0.037) and Triglyceride (r= -0.576, p-value = 0.003), had a moderate negative correlation with SSA levels. In a One-Way Analysis of Covariance (Adjusted for TG and BAI), SSA could distinguish between diabetics with retinopathy and those without complications (p-value = 0.004) but not nephropathy (p-value = 0.099). Within group linear regression analysis showed that Elevated serum sialic acid was found in type 2 diabetic patients with retinopathic micro-vascular complications. Therefore, estimation of sialic acid levels may help with the early prediction and prevention of microvascular complications occurring due to diabetes, thereby decreasing the mortality and morbidity.

Subtractive assembly for comparative metagenomics, and its application to type 2 diabetes metagenomes

Comparative metagenomics remains challenging due to the size and complexity of metagenomic datasets. Here we introduce subtractive assembly, a de novo assembly approach for comparative metagenomics that directly assembles only the differential reads that distinguish between two groups of metagenomes. Using simulated datasets, we show it improves both the efficiency of the assembly and the assembly quality of the differential genomes and genes. Further, its application to type 2 diabetes (T2D) metagenomic datasets reveals clear signatures of the T2D gut microbiome, revealing new phylogenetic and functional features of the gut microbial communities associated with T2D.

Sialic acid and incidence of hospitalization for diabetes and its complications during 40-years of follow-up in a large cohort: the Värmland survey

AIM

To examine the association of sialic acid (SA) with first recorded diabetes mellitus-related hospitalization.

METHODS

From a population-based study in Värmland, Sweden, between 1962 and 1965, 87,035 men and women were selected and followed for first recorded diabetes-related hospitalization until 2005. The association of SA was calculated and stratified for gender by Cox's proportional hazards models. Adjustments were made for conventional risk factors and socioeconomic status. Association analyses were made for comparisons between SA-levels above and below median.

RESULTS

The mean age was 47.2 (SD 13.0) years and the total numbers of incident diabetes-related hospitalizations in men and women were 3445 and 3273, respectively. Hazard ratios per one standard deviation of SA were 1.12 (95% CI: 1.08-1.17, p<0.0001) in men and 1.17 (95% CI: 1.13-1.22, p<0.0001) in women. Interaction analyses indicated a relatively higher SA-associated risk in women than in men with above median SA levels.

CONCLUSIONS

In this large population-based cohort followed for more than 40 years, elevated SA, as a marker of systemic inflammation, was independently associated with risk of diabetes and diabetes-related hospitalizations.

A comparison of the effect of glitazones on serum sialic acid in patients with type 2 diabetes

Although management of hyperglycaemia represents one of the principal treatment goals of diabetes therapy, the high incidence of cardiovascular (CV) complications in diabetes also needs effective management. Therefore, the present study was designed to determine and compare the effect of glitazones on serum sialic acid (SSA), a known risk marker for CV disease, along with fasting plasma glucose (FPG), glycohaemoglobin (HbA1-c) and blood lipids, in overweight, previously only diet-treated patients with type 2 diabetes (n=60). The study was conducted for a period of 12 months. Significant improvement in FPG and HbA1-c were shown by both rosiglitazone (p<0.003 and p<0.001, respectively) and pioglitazone (p<0.005 and p<0.001, respectively), compared with baseline, and pioglitazone showed greater beneficial effects on other parameters monitored, significantly reducing total cholesterol (TC) (p≤0.05). Both the drugs showed a decrease in SSA and no significant differences were observed between the groups. However, the decrease was significant only in the pioglitazone-treated group at month 12 (p≤0.05), compared with baseline. A significant decrease in SSA by pioglitazone indicates its greater cardioprotective effect compared with rosiglitazone.