Study of association of serum uric acid with albuminuria and carotid atherosclerosis in type 2 diabetes mellitus patients

The relationship between serum uric acid level and carotid intima-media thickness in hemodialysis patients

INTRODUCTION

We aimed to evaluate the relationship between carotid intima-media thickness (CIMT), which is a known indicator of cardiovascular risk and atherosclerosis, and uric acid level, which may be an easy marker for cardiovascular diseases due to its antioxidant and pro-oxidant properties in hemodialysis patients.

METHODS

In this cross-sectional study, we evaluated 77 hemodialysis patients. The mean CIMT of these patients was measured and recorded by Doppler ultrasonography. Patients were divided into two groups according to their serum uric acid levels. Correlation analysis and linear regression analysis were used to define the relationship between study parameters.

FINDINGS

The mean CIMT levels in the normouricemic group and the hyperuricemic group were 0.95 ± 0.15 and 1.07 ± 0.15, respectively. There was a statistically significant difference between the two groups (p = 0.001). There was a statistically significant and moderate linear correlation between serum uric acid level and mean CIMT (r = 0.402; p = 0.002). Univariate and multivariate linear regression analyses were performed to identify variables that could independently affect the mean CIMT value. According to analysis, uric acid (p < 0.001), hypertension (p = 0.008), albumin (p = 0.029), and C-reactive protein (p = 0.042) were found independent risk factors for mean CIMT value.

DISCUSSION

We found a significant relationship between serum uric acid level and CIMT, which indicates carotid atherosclerosis. Serum uric acid level is a low-cost laboratory parameter that can be measured in almost all laboratories, and it may be valuable in the hemodialysis patient group to identify patients at high risk of carotid atherosclerosis.

Association between uric acid level and contrast-induced acute kidney injury in patients with type 2 diabetes mellitus after coronary angiography: a retrospective cohort study

BACKGROUND

This study assessed the predictive value of uric acid (UA) for contrast-induced acute kidney injury (CI-AKI) in patients with type 2 diabetes mellitus (T2DM) who underwent coronary angiography (CAG). A nomogram to aid in the prediction of CI-AKI was also developed and validated, and the construction of a prognostic nomogram combined with clinical features was attempted.

METHODS

This study retrospectively enrolled T2DM patients who underwent CAG between December 2019 and December 2020 at the Affiliated Zhongda Hospital of Southeast University. Multivariable logistic regression analysis was used for the analysis of clinical outcomes. Receiver operating characteristic (ROC) analyses were performed to determine the area under the ROC curve (AUC) and the cut-off points for continuous clinical data. The prediction accuracies of models for CI-AKI were estimated through Harrell's concordance indices (C-index). Nomograms of the prognostic models were plotted for individualized evaluations of CI-AKI in T2DM patients after CAG.

RESULTS

A total of 542 patients with T2DM who underwent CAG were included in this study. We found that a high UA level (≥ 425.5 µmol/L; OR = 6.303), BUN level (≥ 5.98 mmol/L; OR = 3.633), Scr level (≥ 88.5 µmol/L; OR = 2.926) and HbA1C level (≥ 7.05%; OR = 5.509) were independent factors for CI-AKI in T2DM patients after CAG. The nomogram model based on UA, BUN, Scr and HbA1C levels presented outstanding performance for CI-AKI prediction (C-index: 0.878). Decision curve analysis (DCA) showed good clinical applicability in predicting the incidence of CI-AKI in T2DM patients who underwent CAG.

CONCLUSION

High UA levels are associated with an increased incidence of CI-AKI in T2DM patients after CAG. The developed nomogram model has potential predictive value for CI-AKI and might serve as an economic and efficient prognostic tool in clinical practice.

Protective Effects of Astragaloside IV on Uric Acid-Induced Pancreatic β-Cell Injury through PI3K/AKT Pathway Activation

Background

Elevated uric acid (UA) has been found to damage pancreatic β-cell, promote oxidative stress, and cause insulin resistance in type 2 diabetes (T2D). Astragaloside IV (AS-IV), a major active monomer extracted from Astragalus membranaceus (Fisch.) Bunge. which belongs to TRIB. Galegeae (Br.) Torrey et Gray, Papilionaceae, exhibits various activities in a pathophysiological environment and has been widely employed to treat diseases. However, the effects of AS-IV on UA-induced pancreatic β-cell damage need to be investigated and the associating mechanism needs to be elucidated. This study was designed to determine the protective effects and underlying mechanism of AS-IV on UA-induced pancreatic β-cell dysfunction in T2D.

Methods

UA-treated Min6 cells were exposed to AS-IV or wortmannin. Thereafter, the 3-(45)-dimethylthiahiazo(-z-y1)-35-di-phenytetrazoliumromide (MTT) assay and flow cytometry were employed to determine the effect of AS-IV on cell proliferation and apoptosis, respectively. Insulin secretion was evaluated using the glucose-stimulated insulin secretion (GSIS) assay. Finally, western blot and quantitative real-time polymerase chain reaction (qRT-PCR) were performed to determine the effect of AS-IV on the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway in UA-treated cells.

Results

AS-IV had no cytotoxic effects on Min6 cells. UA significantly suppressed Min6 cell growth, promoted cell apoptosis, and enhanced caspase-3 activity; however, AS-IV abolished these effects in a dose-dependent manner. Further, decreased insulin secretion was found in UA-treated Min6 cells compared to control cells, and the production of insulin was enhanced by AS-IV in a dose-dependent manner. AS-IV significantly increased phosphorylated (p)-AKT expression and the ratio of p-AKT/AKT in Min6 cells exposed to UA. No evident change in AKT mRNA level was found in the different groups. However, the effects of AS-IV on UA-stimulated Min6 cells were reversed by 100 nM wortmannin.

Conclusion

Collectively, our data suggest that AS-IV protected pancreatic β-cells from UA-treated dysfunction by activating the PI3K/AKT pathway. Such findings suggest that AS-IV may be an efficient natural agent against T2D.

Serum Uric Acid and Diabetes: From Pathophysiology to Cardiovascular Disease

Hyperuricemia, has been traditionally related to nephrolithiasis and gout. However, it has also been associated with the development of type 2 diabetes mellitus (T2DM) and cardiometabolic and cardiovascular diseases. Pathophysiologically, elevated serum uric acid (SUA) levels may be associated with abnormal lipid and glucose metabolism. In this narrative review, we consider the associations between hyperuricemia, hyperglycemia, atherosclerosis and thrombosis. Furthermore, we comment on the available evidence linking elevated SUA levels with the incidence and outcomes of coronary heart disease, stroke, peripheral artery disease and non-alcoholic fatty liver in subjects with T2DM. The effects of antidiabetic drugs (e.g. metformin, pioglitazone, sulfonylureas, dipeptidyl peptidase 4 inhibitors, glucagon-like peptide-1 receptor agonists, sodium-glucose cotransporter 2 inhibitors and insulin) on SUA concentrations are also reviewed.

Genetically predicted serum uric acid levels and the risk of coronary artery disease in patients with diabetes: A Mendelian randomization study

BACKGROUND AND AIMS

Serum uric acid (SUA) levels have been reported to be associated with an increased risk of coronary artery disease (CAD) among patients with diabetes in observational study. Whether this relationship is causal remains unclear. The current study aimed to explore the causal association between SUA and the risk of CAD in patients with diabetes.

METHODS AND RESULTS

A two-sample Mendelian randomization (MR) approach was employed to evaluate the causal effect of SUA on the risk of CAD in patients with diabetes. A total of 28 single nucleotide polymorphisms (SNPs) related to SUA were identified as instruments. Genetic association with CAD were obtained from a recently published genome-wide association study (GWAS) of 15,666 patients with diabetes (3968 CAD cases and 11,696 controls). The fixed-effects inverse variance-weighted method was employed to estimate the causal effect for the primary analysis, and other robust methods were employed for sensitivity analyses. In addition, the whole analyses were repeated using 9 non-pleiotropic SNPs. Genetic determined SUA levels were not significantly associated with the risk of CAD in patients with diabetes in the primary analysis (odds ratio = 1.13, 95% confidence interval: 0.98-1.16, P = 0.09). Consistent results were observed in the sensitivity analyses using various robust methods. In addition, this finding was confirmed by the repeated analyses using 9 non-pleiotropic SNPs.

CONCLUSIONS

This two-sample MR study does not support a causal effect of genetically predicted SUA levels on the risk of CAD in patients with diabetes.

Harnessing hyperuricemia to atherosclerosis and understanding its mechanistic dependence

Atherosclerosis is regarded as the disease of the arterial vasculature. The main characteristics of atherosclerosis are the abnormal accumulation of lipids, increased inflammatory cells, matrix deposits, and proliferation of smooth muscle cells. Diabetes mellitus, obesity, and hyperlipidemia are the most studied risk factors of atherosclerosis. One least studied risk factor is the uric acid (UA), a high UA in circulation is interlinked with many pathological processes. Several epidemiological studies suggest elevated UA levels as an essential biomarker in the forecast of several cardiovascular diseases. Available evidence claims that UA upholds the atherosclerosis process via disturbing lipid metabolism, reducing the nitric oxide synthesis in endothelial cells, promoting the proliferation of vascular smooth muscle cells, and overwhelms inflammation. In endothelial dysfunction and coronary artery lesions, UA is considered as an independent predictor. The updated studies on the involvement of hyperuricemia in atherosclerosis prove that treatment with xanthine oxidase (XO) inhibitors not just benefits the treatment of hyperuricemia but also reduces the burden of atherosclerosis to a greater extent. In this review, we highlight how the hyperuricemia affects vascular integrity, causes atherosclerosis, and the mechanism of action of XO inhibitors on atherosclerosis.

Hsa_circ_0000345 regulates the cellular development of ASMCs in response to oxygenized low-density lipoprotein

The interaction between circRNAs and atherosclerosis has been extensively studied. However, more novel circRNAs need to be explored to help establish a perfect regulatory network. In the present research, hsa_circ_0000345 was demonstrated to regulate cellular development of oxygenized low‐density lipoprotein (ox‐LDL)‐treated aortic smooth muscle cells (ASMCs), which was closely related to the occurrence and progress of atherosclerosis. Ox‐LDL exposure remarkably decreased hsa_circ_0000345 expression in ASMCs. Transfection‐induced hsa_circ_0000345 overexpression activated cell viability (detected by an MTT assay) and restrained cellular apoptosis (analysed by flow cytometry) in the atherosclerosis cellular model. While down‐regulation of hsa_circ_0000345 reduced cell viability and promoted cell apoptosis. In addition, the data of the cell cycle distribution analysis and trans‐well assay indicated that cell cycle progression was arrested at the G1 phase while cell invasion was enhanced in ASMCs following treatment of ox‐LDL in the context of hsa_circ_0000345 OE plasmids. In addition, up‐regulation of hsa_circ_0000345 supported HIF‐1α at both the mRNA and protein level, and down‐regulation of hsa_circ_0000345 reduced HIF‐1α expression. Overall, the above findings revealed that hsa_circ_0000345 was a dramatic regulator of ASMCs proliferation, apoptosis and invasion in response to ox‐LDL treatment. Hsa_circ_0000345 was identified as a protector of cell viability during ox‐LDL induced cell development.