Genetically elevated circulating homocysteine concentrations increase the risk of diabetic kidney disease in Chinese diabetic patients

A lateral flow strip for on-site detection of homocysteine based on a truncated aptamer

An elevated level of homocysteine (Hcy) in serum is closely related to the development of various diseases. Therefore, homocysteine has been widely employed as a biomarker in medical diagnosis and the on-site detection of homocysteine is highly desired. In this study, a truncated highly specific aptamer for homocysteine was screened and used to design a lateral flow strip (LFS) for the detection of homocysteine. The aptamer was derived from a previously reported sequence. Based on the result of molecular docking, the original sequence was subjected to truncation, resulting in a reduction of the length from 66 nt to 55 nt. Based on the truncated aptamer, the LFS was designed for the detection of homocysteine. In the presence of homocysteine, the aptamer selectively binds to it, releasing cDNA from the aptamer/cDNA duplex. This allows cDNA to bind to the capture probe immobilized on the T zone of the strip, resulting in a red signal on the T zone from gold nanoparticles (AuNPs). The strip enables the visual detection of homocysteine in 5 min. Quantitative detection can be facilitated with the aid of ImageJ software. In this mode, the linear detection range for homocysteine is within 5-50 μM, with a detection limit of 4.18 μM. The strip has been effectively utilized for the detection of homocysteine in human serum. Consequently, the combination of the truncated aptamer and the strip offers a method that is sensitive, quick, and economical for the on-site detection of homocysteine.

A critical review on therapeutic approaches of CRISPR-Cas9 in diabetes mellitus

Diabetes mellitus (D.M.) is a common metabolic disorder caused mainly by combining two primary factors, which are (1) defects in insulin production by the pancreatic β-cells and (2) responsiveness of insulin-sensitive tissues towards insulin. Despite the rapid advancement in medicine to suppress elevated blood glucose levels (hyperglycemia) and insulin resistance associated with this hazard, a demand has undoubtedly emerged to find more effective and curative dimensions in therapeutic approaches against D.M. The administration of diabetes treatment that emphasizes insulin production and sensitivity may result in unfavorable side effects, reduced adherence, and potential treatment ineffectiveness. Recent progressions in genome editing technologies, for instance, in zinc-finger nucleases, transcription activator-like effector nucleases, and clustered regularly interspaced short palindromic repeat (CRISPR-Cas)-associated nucleases, have greatly influenced the gene editing technology from concepts to clinical practices. Improvements in genome editing technologies have also opened up the possibility to target and modify specific genome sequences in a cell directly. CRISPR/Cas9 has proven effective in utilizing ex vivo gene editing in embryonic stem cells and stem cells derived from patients. This application has facilitated the exploration of pancreatic beta-cell development and function. Furthermore, CRISPR/Cas9 enables the creation of innovative animal models for diabetes and assesses the effectiveness of different therapeutic strategies in treating the condition. We, therefore, present a critical review of the therapeutic approaches of the genome editing tool CRISPR-Cas9 in treating D.M., discussing the challenges and limitations of implementing this technology.

Unraveling the Crosstalk between Lipids and NADPH Oxidases in Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a serious complication of diabetes mellitus and a leading cause of end-stage renal disease. Abnormal lipid metabolism and intrarenal accumulation of lipids have been shown to be strongly correlated with the development and progression of diabetic kidney disease (DKD). Cholesterol, phospholipids, triglycerides, fatty acids, and sphingolipids are among the lipids that are altered in DKD, and their renal accumulation has been linked to the pathogenesis of the disease. In addition, NADPH oxidase-induced production of reactive oxygen species (ROS) plays a critical role in the development of DKD. Several types of lipids have been found to be tightly linked to NADPH oxidase-induced ROS production. This review aims to explore the interplay between lipids and NADPH oxidases in order to provide new insights into the pathogenesis of DKD and identify more effective targeted therapies for the disease.

The association of homocysteine level with the risk of diabetic nephropathy and diabetic retinopathy in NHANES

AIMS

To examine the association of homocysteine (Hcy) with diabetic nephropathy (DN) and diabetic retinopathy (DR) in a representative United States population.

METHODS

This was a cross-sectional study using data from participants in the National Health and Nutrition Examination Survey 2005-2006. Metrics including Hcy level, urinary albumin to creatinine ratio, estimated glomerular filtration rate, and retinopathy grading were collected. Multiple logistic regression models were employed to assess the association of Hcy with DN and DR.

RESULTS

630 participants were included in this study. The Hcy level was significantly higher in those with DN and DR than those without DN and DR. Hcy was associated with an increased risk of DN (OR = 1.31, 95% CI 1.18-1.46; P < 0.001). In the fully adjusted model of DN (model II), compared to participants in quartiles 1 of Hcy, the adjusted ORs for participants in quartiles 2-4 were 1.49 (95% CI 0.52-4.26; P = 0.426), 3.81 (95% CI 1.35-10.73; P = 0.015), and 14.08 (95% CI 3.84-51.66; P = 0.001), respectively. Hcy was also associated with an increased risk of DR (OR = 2.260, 95% CI 1.212-4.216; P = 0.014), but this association was non-significant in the fully adjusted model of DR (model II).

CONCLUSIONS

In diabetic patients, Hcy was associated with increased risk of DN in a non-linear manner. In addition, Hcy was associated with the risk of DR, but the association was attenuated after adjusting for confounders. In the future, Hcy can potentially be used as an early screening indicator for diabetic microvascular complications.

Increased Plasma Homocysteine Levels Are Associated with Left Ventricular Hypertrophy in Hypertensive Patients with Normal Renal Function

INTRODUCTION

Renal function has an important bearing on plasma homocysteine levels. Plasma homocysteine is related to left ventricular hypertrophy (LVH). However, it remains unclear whether the association between plasma homocysteine levels and LVH is influenced by renal function. This study aimed to investigate relationships among left ventricular mass index (LVMI), plasma homocysteine levels, and renal function in a population from southern China.

METHODS

A cross-sectional study was performed in 2,464 patients from June 2016 to July 2021. Patients were divided into three groups based on gender-specific tertiles of homocysteine levels. LVMI ≥115 g/m2 for man or ≥95 g/m2 for woman was defined as LVH.

RESULTS

LVMI and the percentage of LVH were increased, while estimated glomerular filtration rate (eGFR) was decreased with the increase in homocysteine levels, both significantly. Multivariate stepwise regression analysis showed that eGFR and homocysteine were independently associated with LVMI in patients with hypertension. No correlation was observed between homocysteine and LVMI in patients without hypertension. Stratified by eGFR, further analysis confirmed homocysteine was independently associated with LVMI (β = 0.126, t = 4.333, p < 0.001) only in hypertensive patients with eGFR ≥90 mL/(min·1.73 m2), not with 60≤ eGFR <90 mL/(min·1.73 m2). Multivariate logistic regression indicated that in hypertensive patients with eGFR ≥90 mL/(min·1.73 m2), the patients in high tertile of homocysteine levels had a nearly twofold increased risk of occurring LVH compared with those in low tertile (high tertile: OR = 2.780, 95% CI: 1.945-3.975, p < 0.001).

CONCLUSION

Plasma homocysteine levels were independently associated with LVMI in hypertensive patients with normal eGFR.

Diagnostic Value of the Combined Measurement of Serum HCY and NRG4 in Type 2 Diabetes Mellitus with Early Complicating Diabetic Nephropathy

PURPOSE

This study aimed to investigate the value of combined detection of HCY and NRG4 in the diagnosis of early diabetic kidney disease (DKD) and to explore the association between the ratio of HCY/NRG4 and DKD.

METHODS

A total of 140 diabetic patients and 43 healthy people were prospectively enrolled. The plasma HCY level, NRG4 level and HCY/NRG4 of them were measured to compare their differences and analyze the correlation with DKD. The independent influencing factors of patients with DKD were screened, and the nomograph of DKD occurrence was constructed.

RESULTS

The levels of HCY and HCY/NRG4 in diabetic patients were significantly increased, while the level of NRG4 was significantly decreased (p < 0.01). The AUCs of HCY/NRG4 predicted for DKD were 0.961. HCY/NRG4 and the course of DM were independent risk factors for DKD. A predictive nomograph of DKD was constructed, and decision curve analysis (DCA) showed good clinical application value. HCY/NRG4 was positively correlated with Scr, UACR, TG, UA, BUN, TCHOL and LDL and negatively correlated with eGFR and HDL (p < 0.05).

CONCLUSIONS

The level of HCY and NRG4 is closely related to the severity of DM, and combined detection of HCY/NRG4 can identify patients with DKD at an early stage.

Tripterygium glycoside tablet attenuates renal function impairment in diabetic nephropathy mice by regulating triglyceride metabolism

Tripterygium glycoside tablet (TGT) has been used clinically to alleviate diabetic nephropathy (DN) for decades. However, the mechanism of its anti-DN has not been fully clarified. The aim of this study was to elucidate molecular mechanism of TGT in repairing renal function injury. The results of biochemical parameters and renal histopathology implied that TGT intervention could attenuate creatinine, albumin excretion rate and histological injury of kidney in DN mouse model. Moreover, UHPLC-QTOF-MS/MS-based untargeted metabolomic analysis indicated that 11 metabolites in kidney of mice with DN were restored after TGT treatment, and the most prominent metabolic alteration was triglyceride (TG) metabolism. Mechanistically, TGT effectively improved the function of impaired kidney by promoting TG catabolism via modulation of adipose triglyceride lipase in DN mice. Our findings identified the link between circulating metabolites and DN, suggesting that it might be a possibility to intervene in DN by targeting metabolism.

Prediction of 3-year risk of diabetic kidney disease using machine learning based on electronic medical records

BACKGROUND

Established prediction models of Diabetic kidney disease (DKD) are limited to the analysis of clinical research data or general population data and do not consider hospital visits. Construct a 3-year diabetic kidney disease risk prediction model in patients with type 2 diabetes mellitus (T2DM) using machine learning, based on electronic medical records (EMR).

METHODS

Data from 816 patients (585 males) with T2DM and 3 years of follow-up at the PLA General Hospital. 46 medical characteristics that are readily available from EMR were used to develop prediction models based on seven machine learning algorithms (light gradient boosting machine [LightGBM], eXtreme gradient boosting, adaptive boosting, artificial neural network, decision tree, support vector machine, logistic regression). Model performance was evaluated using the area under the receiver operating characteristic curve (AUC). Shapley additive explanation (SHAP) was used to interpret the results of the best performing model.

RESULTS

The LightGBM model had the highest AUC (0.815, 95% CI 0.747-0.882). Recursive feature elimination with random forest and SHAP plot based on LightGBM showed that older patients with T2DM with high homocysteine (Hcy), poor glycemic control, low serum albumin (ALB), low estimated glomerular filtration rate (eGFR), and high bicarbonate had an increased risk of developing DKD over the next 3 years.

CONCLUSIONS

This study constructed a 3-year DKD risk prediction model in patients with T2DM and normo-albuminuria using machine learning and EMR. The LightGBM model is a tool with potential to facilitate population management strategies for T2DM care in the EMR era.

Homocysteine and diabetes: Role in macrovascular and microvascular complications

Diabetes mellitus (DM) can lead to the development of macro- and microvascular complications. Homocysteine (Hcy) may play a role in the development of cardiovascular (CV) diseases (CVDs). The role of Hcy in the development of the vascular complications associated with DM is not clearly defined. Despite a strong initial assumption regarding the importance of Hcy in DM and its complications, over time "enthusiasm has waned" because several studies showed unconvincing and occasionally contradictory results. A universal conclusion is not easy to draw given the diversity of studies (e.g. number of patients, design, folic acid and vitamin B status, ethnic differences, genetic background). For some complications, most results encourages further investigation. Impaired renal function is a major independent determinant of high total Hcy (tHcy) levels. However, the role of hyperhomocysteinaemia (HHcy) in the development of diabetic kidney disease (DKD) has yet to be determined. Hcy-lowering therapies can significantly decrease Hcy levels but their effects on CVD risk reduction are conflicting. Further studies are needed to determine the influence of Hcy-lowering therapy on CVD risk reduction, especially in patients with DM.

Scutellarin Reduce the Homocysteine Level and Alleviate Liver Injury in Type 2 Diabetes Model

Scutellarin (SCU) is an active ingredient extracted from Erigeron breviscapus (Vaniot) Hand.-Mazz. Its main physiological functions are anti-inflammatory and antioxidant. In this study, we established a STZ-induced model of type 2 diabetes (T2DM) and a homocysteine (Hcy)-induced apoptosis model of LO2 to investigate whether SCU can alleviate liver damage by regulating Hcy in type 2 diabetes. Biochemical analysis indicated that SCU could improve the lipid metabolism disorder and liver function in diabetic rats by downregulating the levels of triglycerides (TG), cholesterol (CHO), low-density lipoprotein (LDL), alanine transaminase (ALT) and aspartate transaminase (AST), and by upregulating the level of high-density lipoprotein (HDL). Interestingly, SCU also could down-regulate the levels of Hcy and insulin and enhance the ability of type 2 diabetic rats to regulate blood glucose. Mechanistically, our results indicated that SCU may control the level of Hcy through regulating the levels of β-Cystathionase (CBS), γ-Cystathionase (CSE) and 5,10-methylenetetrahydrofolate (MTHFR) in liver tissue, and up-regulate folic acid, VitB₆ and VitB₁₂ levels in serum. Furthermore, SCU inhibits apoptosis in the liver of T2DM rats and in cultured LO2 cells treated with Hcy. Together, our findings suggest that SCU may alleviate the liver injury thorough downregulating the level of Hcy in T2DM rats.

Relationship between plasma total homocysteine and the severity of renal function in Chinese patients with type 2 diabetes mellitus aged ≥75 years

We aimed to investigate the relationship between total homocysteine (tHcy) levels in the plasma and renal function severity in patients with type 2 diabetes mellitus (T2DM) aged ≥75 years.We included 221 patients with T2DM aged ≥60 years (59 aged ≥75 years).tHcy levels among the 4 groups of patients aged ≥60 years significantly differed, but not in those aged ≥75 years. tHcy levels in patients aged ≥60 years were negatively correlated with the estimated glomerular filtration rate. The area under the receiver operating characteristic curve of tHcy for predicting diabetic kidney disease (DKD) was 0.636. Fasting c-peptide and creatinine were independently associated with tHcy levels in patients aged ≥60 years, whereas insulin and creatinine were independently associated with tHcy levels in those aged ≥75 years.tHcy concentrations were elevated in T2DM and can potentially serve as a risk factor for DKD, but it is not an ideal biomarker.

A compound reflects the level of homocysteine based on Rhodamine B and its ability to respond to homocysteine in the plasma of diabetic patients

BACKGROUND

The level of homocysteine (Hcy) is significantly elevated in the plasma of patients with diabetes. The increased plasma Hcy level is positively correlated with the severity of the disease and is one of the important causes of diabetic complications.

METHODS

We designed and synthesized a compound could reflect the level of Hcy based on rhodamine B, and the structure was verified by 1H-NMR and EI-HRMS. Then, the linearity, repeatability, selectivity, and cellar toxicity, the effects of the fluid viscosity and pH of compound on Hcy were measured; meanwhile, the response of Hcy level in the plasma of diabetic patients was detected.

RESULTS

This is a novel compound that has never been reported. The compound showed a satisfactory linear range and repeatability at the viscosity and pH of physiological fluid. In addition, the compound was capable of evading the interference from other amino acids and metal ions, and it exhibited high selectivity toward Hcy.

CONCLUSION

The compound showed increased responsiveness to plasma Hcy in patients with diabetes in comparison with healthy individuals and effectively reflected plasma Hcy levels in healthy individuals and diabetic patients. Therefore, the compound is expected to be used in the diagnosis of diabetes mellitus.

Effects of insulin combined with metformin on serum cystatin C, homocysteine and maternal and neonatal outcomes in pregnant women with gestational diabetes mellitus

Effects of insulin combined with metformin on serum cystatin C (Cys C), homocysteine (Hcy) and maternal and neonatal outcomes in pregnant women with gestational diabetes mellitus (GDM) were investigated. In total, 80 cases of pregnant women diagnosed with GDM in the Department of Obstetrics and Gynecology of Liaocheng Third People's Hospital from July 2015 to July 2017 were selected and divided into a study group (42 cases) and a control group (38 cases). The study group was treated with insulin combined with metformin, and the control group was treated with insulin. Fasting blood glucose (FBG) and postprandial blood glucose after 2 h (2hPG) of the two groups were compared before and after treatment. Levels of serum Cys C, Hcy, urinary protein (UmAlb), postpartum maternal outcomes and adverse reactions during pregnancy were compared in the two groups before and after treatment. After treatment, the level of FBG and 2hPG in the control group was higher than that in the treatment group (P<0.05). After treatment, the level of serum Cys C and Hcy in both groups were lower than that before the treatment, and the level in the study group was lower than that in the control group (P<0.05). The total incidence of neonatal adverse outcomes and the number of adverse pregnancies in GDM patients in the study group were significantly lower than those in the control group (P<0.05). There were no significant differences in adverse reactions during pregnancy between the two groups (P>0.05). In conclusion, insulin combined with metformin is more effective than insulin alone in reducing serum Cys C and Hcy levels, with significant effect on the improvement of maternal and neonatal outcomes.

Genetically elevated circulating homocysteine concentrations increase the risk of diabetic kidney disease in Chinese diabetic patients

Diabetic kidney disease (DKD) is a devastating and frequent complication of diabetes mellitus. Here, we first adopted methylenetetrahytrofolate reductase (MTHFR) gene C677T polymorphism as an instrument to infer the possible causal relevance between circulating homocysteine and DKD risk in a Chinese population and next attempted to build a risk prediction model for DKD. This is a hospital‐based case‐control association study. Total 1107 study participants were diagnosed with type 2 diabetes mellitus, including 547 patients with newly diagnosed and histologically confirmed DKD. MTHFR gene C677T polymorphism was determined using the TaqMan method. Carriers of 677TT genotype (14.55 μmol/L) had significantly higher homocysteine concentrations than carriers of 677CT genotype (12.88 μmol/L) (P < 0.001). Carriers of 677TT genotype had a 1.57‐fold increased risk of DKD (odds ratio: 1.57, 95% CI: 1.21‐2.05, P = 0.001) relative to carriers of 677CT genotype after adjusting for confounders. Mendelian randomization analysis revealed that the odds ratio for DKD relative to diabetes mellitus per 5 μmol/L increment of circulating homocysteine concentrations was 3.86 (95% confidence interval: 1.21‐2.05, P < 0.001). In the Logistic regression analysis, hypertension, homocysteine and triglyceride were significantly associated with an increased risk of DKD and they constituted a risk prediction model with good test performance and discriminatory capacity. Taken together, our findings provide evidence that elevated circulating homocysteine concentrations were causally associated with an increased risk of DKD in Chinese diabetic patients.