Is Neuregulin-4 a predictive marker of microvascular complications in type 2 diabetes mellitus?

Bioinformatic analyses reveal lysosomal-associated protein transmembrane 5 as a potential therapeutic target in lipotoxicity-induced injury in diabetic kidney disease

Emerging data have revealed that damage to tubular epithelial cell is a driving force in the progression of diabetic kidney disease (DKD). However, the specific mechanisms by which lipotoxicity contributes to the injury of these cells, thereby influencing the development of DKD, are yet to be fully understood. Here, we analyzed the GSE 30529 microarray datasets of human tubulointerstitial tissue samples from the Gene Expression Omnibus database (GEO). Concurrently, we conducted RNA-sequencing on palmitic acid (PA)-treated human renal proximal tubule epithelial cells (HK2 cells). After normalization, the differentially expressed genes (DEGs) were screened by R software and gene ontology (GO) enrichment analysis was conducted, and lysosomal-associated protein transmembrane 5 (LAPTM5) was finally selected. Our findings indicate that the expression of LAPTM5 was obviously increased in DKD patients, and the correlation between LAPTM5, and other clinical parameters of DKD was analyzed using the Spearman correlation analysis. The potential of LAPTM5 as a prognostic biomarker for DKD was further consolidated through receiver operating characteristic (ROC) analysis. To further verify the function of LAPTM5, we established mouse or in vitro systems mimicking DKD. The results showed that a consistent upregulation of LAPTM5, which was also found to be linked with inflammatory mediators within the context of DKD. Additionally, LAPTM5 silencing significantly downregulated mRNA expression of inflammatory factors in PA-treated HK2 cells. These results indicate that LAPTM5 is a potential biomarker and therapeutic treatment target for DKD. This discovery paves the way for future research and development of targeted interventions aimed at mitigating the progression of this prevalent condition.

Fluorofenidone attenuates renal fibrosis by inhibiting lysosomal cathepsin‑mediated NLRP3 inflammasome activation

Currently, no antifibrotic drug in clinical use can effectively treat renal fibrosis. Fluorofenidone (AKFPD), a novel pyridone agent, significantly reduces renal fibrosis by inhibiting the activation of the NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome; however, the underlying mechanism of this inhibition is not fully understood. The present study aimed to reveal the molecular mechanism underlying the suppression of NLRP3 inflammasome activation by AKFPD. It investigated the effect of AKFPD on NLRP3 activation and lysosomal cathepsins in a unilateral ureteral obstruction (UUO) rat model, and hypoxia/reoxygenation (H/R)-treated HK-2 cells and murine peritoneal-derived macrophages (PDMs) stimulated with lipopolysaccharide (LPS) and ATP. The results confirmed that AKFPD suppressed renal interstitial fibrosis and inflammation by inhibiting NLRP3 inflammasome activation in UUO rat kidney tissues. In addition, AKFPD reduced the production of activated caspase-1 and maturation of IL-1β by suppressing NLRP3 inflammasome activation in H/R-treated HK-2 cells and murine PDMs stimulated with LPS and ATP. AKFPD also decreased the activities of cathepsins B, L and S both in vivo and in vitro. Notably, AKFPD downregulated cathepsin B expression and NLRP3 colocalization in the cytoplasm after lysosomal disruptions. Overall, the results suggested that AKFPD attenuates renal fibrosis by inhibiting lysosomal cathepsin-mediated activation of the NLRP3 inflammasome.

Downregulation of lncRNA XLOC_032768 in diabetic patients predicts the occurrence of diabetic nephropathy

LncRNA XLOC_032768 is reported to prevent renal tubular epithelial cells from cisplatin-induced apoptosis, suggesting its involvement in the development of kidney injury. The present study aimed to explore the role of XLOC_032768 in diabetic nephropathy (DN). The present study enrolled a total of 140 healthy controls (Control group) and 140 patients with type 2 diabetes (Diabetes group). Expression of XLOC_032768 in plasma from these participants was analyzed by performing RT-qPCR. The 140 diabetic patients were followed up for 5 years to monitor the occurrence of diabetic complications. The role of XLOC_032768 in predicting the occurrence of diabetic complications, including DN, diabetic cardiomyopathy (DC), diabetic retinopathy (DR), and diabetic foot (DF) were analyzed by plotting receiver operating characteristic curves and complication-free curves. On the day of admission, plasma levels of XLOC_032768 were not significantly different between Control and Diabetes groups. During follow-up, a total of 22, 15, 13, and 15 cases were diagnosed as DN, DC, DR, and DF, respectively. On the day of diagnosis, plasma levels of XLOC_032768 were only decreased in DN group, but not in other groups, compared to plasma levels of XLOC_032768 on the day of admission. Using plasma levels of XLOC_032768 on the day of admission as a biomarker, potential DN patients were effectively separated from patients with other potential complications and diabetic patients without complications. The 140 diabetic patients were grouped into high and low XLOC_032768 level groups. It was observed that low XLOC_032768 level group showed increased occurrence of DN, but not other complications, compared to high XLOC_032768 level group. Therefore, the downregulation of lncRNA XLOC_032768 in diabetic patients may predict the occurrence of DN.

Search progress of pyruvate kinase M2 (PKM2) in organ fibrosis

Fibrosis is characterized by abnormal deposition of the extracellular matrix (ECM), leading to organ structural remodeling and loss of function. The principal cellular effector in fibrosis is activated myofibroblasts, which serve as the main source of matrix proteins. Metabolic reprogramming, transitioning from mitochondrial oxidative phosphorylation to aerobic glycolysis, is widely observed in rapidly dividing cells such as tumor cells and activated myofibroblasts and is increasingly recognized as a fundamental pathogenic basis in organ fibrosis. Targeting metabolism represents a promising strategy to mitigate fibrosis. PKM2, a key enzyme in glycolysis, plays a pivotal role in metabolic reprogramming through allosteric regulation, impacting both metabolic and non-metabolic pathways. Therefore, metabolic reprogramming induced by PKM2 activation is involved in the occurrence and development of fibrosis in various organs. A comprehensive understanding of the role of PKM2 in fibrotic diseases is crucial for seeking new anti-fibrotic therapeutic targets. In this context, we summarize PKM2's role in glycolysis, mediating the intricate mechanisms underlying fibrosis in multiple organs, and discuss the potential value of PKM2 inhibitors and allosteric activators in future clinical treatments, aiming to identify novel therapeutic targets for proliferative fibrotic diseases.

Investigation of the reasons for delayed presentation in proliferative diabetic retinopathy patients

AIM

To investigate reasons for delayed presentation in patients with proliferative diabetic retinopathy (PDR).

METHODS

A questionnaire was designed to investigate consecutive PDR patients with delayed presentation who visited our center between January 2021 and December 2021. The questionnaire was divided into four sections: knowledge regarding diabetic retinopathy (DR), attitude toward DR treatment, difficulties adhering to follow-up plans, and medical care. The systemic disease status and severity of DR were recorded. Logistic analysis was undertaken to investigate DR treatment refusal and delay factors.

RESULTS

A total of 157 patients were included in this study, with an average age of 50.0 ± 11.6 years. The median glycated hemoglobin level (HbA1c) was 7.8% (IQR 2.5%). Among the 157 eyes, most required vitrectomy intervention (144, 91.7%); 17 developed neovascular glaucoma (NVG), while only 13 required additional photocoagulation. Among the 36 patients with undiagnosed DM, the reason for delayed DR presentation was a lack of awareness of DM status among these patients (36 cases, 100.0%). Most of the patients with a known history of DM exhibited inadequate DR knowledge (29, 24.0%), believed their good visual acuity did not require DR screening (98, 81.0%), and had poorly controlled diabetes (113, 93.3%). Factors related to refusing DR treatment were patients with an inability to receive regular diabetes treatment in internal medicine clinics (OR 6.78, 95% CI 1.73-26.59, p = 0.006), patients who could not tolerate discomfort during ophthalmic examination and treatment (OR 15.15, 95% CI 2.70-83.33, p<0.001), and patients who did not have any retinal abnormalities detected and were not informed about the need for regular screening (OR 2.05, 95% CI 1.36-3.09, p<0.001).

CONCLUSIONS

This study investigated the factors contributing to delayed presentation among patients with PDR. Many individuals in the delayed population were found to have undiagnosed DM. Among patients already aware of their DM status, reasons for delay included insufficient knowledge about DR, negative attitudes toward screening and treatment, and difficulties seeking medical care in real-life situations. Furthermore, there needed to be more improvements in the detection, treatment, and follow-up of DR by internal medicine practitioners and ophthalmologists.

Association between red cell distribution width-and-albumin ratio and the risk of peripheral artery disease in patients with diabetes

Aim

The aim of this study is to explore the association between red blood cell distribution width-to-albumin ratio (RAR) and the risk of peripheral artery disease (PAD) in patients with diabetes.

Methods

This cross-sectional study extracted the data of 1,125 participants with diabetes from the National Health and Nutrition Examination Survey database. A weighted univariable logistic regression model was used to explore variables associated with PAD. With PAD as the outcome variable, a weighted logistic regression model was established. The odds ratio (OR) and 95% confidence interval (CI) were effect size.

Results

After adjusting for covariates, the risk of PAD in patients with diabetes was observed in those with higher RAR (OR = 1.83; 95% CI: 1.06-3.15). In addition, RAR ≥3.25 was related to increased risk of PAD in patients with diabetes (OR = 2.04; 95% CI: 1.05-3.95). In people with diabetes aged ≥65, RAR was a risk factor for PAD with an OR value of 2.67 (95% CI: 1.30-5.46). RAR ≥3.25 was associated with increased risk of PAD (OR = 3.06; 95% CI: 1.15-8.11) relative to RAR <2.80. In people with diabetes who smoked, the risk of PAD was elevated in those with RAR ≥3.25 (OR = 2.85; 95% CI: 1.28-6.32). As for patients with cardiovascular disease, the risk of PAD was elevated as the increase of RAR (OR = 2.31; 95% CI: 1.05-5.10). RAR ≥3.25 was correlated with increased risk of PAD (OR = 3.75; 95% CI: 1.42-9.87). The area under the curve of RAR for the risk of PAD in patients with diabetes was 0.631 (95% CI: 0.588-0.675).

Conclusion

A higher RAR was related to increased risk of PAD in patients with diabetes. The findings might offer a reference for the management of PAD in patients with diabetes.

Serum Metrnl is Decreased in Metabolic Dysfunction-Associated Fatty Liver Disease: A Case-Control Study

Context

Metrnl is a novel adipokine mainly produced by white adipose tissue, which plays important roles in insulin sensitization, and energy homeostasis. However, information about the function of Metrnl in Metabolic dysfunction-associated fatty liver disease (MAFLD) remains unclear.

Methods

This is a control study, which enrolled 176 adults with MAFLD and 176 normal controls. They were matched in body mass index (BMI), age, and sex. Serum Metrnl was determined by ELISA. Other biochemical data were also collected.

Results

Compared to the controls, circulating Metrnl was prominently decreased in the MAFLD adults (P<0.001). Next, binary logistic regression model indicated that sex, waist circumference (WC), triglyceride, γ-gamma glutamyl transferase(γ-GGT), and Metrnl was independently associated with MAFLD. Further, as Metrnl levels elevated across its tertiles, the rate of MAFLD decreased (67.52, 66.95, and 15.38%; P value for trend<0.001). Data from multivariate logistic regression models evidenced that compared with the lowest tertile of Metrnl, the odds ratio of MAFLD was 0.023(95% CI 0.006-0.086, P<0.001) for the highest tertile after adjusting for potential confounders. Besides, area under ROC curve of Metrnl for diagnosis MAFLD was 0.755(95% CI 0.705-0.805). Metrnl was positively correlated with diastolic blood pressure, WC, BMI, systolic blood pressure, γ-GGT, and Creatinine in MAFLD. Finally, we found systolic blood pressure and Creatinine were independently related to serum Metrnl in MAFLD.

Conclusion

Serum Metrnl is reduced in adult with MAFLD. The results suggest that Metrnl may be a protective factor associated with the pathogenesis of MAFLD.

Fatty acid-binding protein-3 and renal function decline in patients with chronic coronary syndrome

BACKGROUND

Renal dysfunction is common in patients with coronary artery disease. Due to the shared vascular pathogenesis between the two conditions, novel biomarkers such as the fatty acid-binding protein-3 (FABP-3) have been proposed for diagnosis and prognosis prediction. This multicentre prospective cohort study investigates the association between FABP-3 and renal dysfunction.

HYPOTHESIS

We hypothesized that higher FABP-3 levels are correlated to worse renal outcome.

METHODS

Patients with chronic coronary syndrome were classified into three groups based on the initial serum FABP-3 levels. The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation was used to estimate the patient's renal function. Renal events were defined as >25% and >50% decline in estimated glomerular filtration rate (eGFR). Cox multivariable regression was employed to delineate the correlation between FABP-3 and renal dysfunction.

RESULTS

A total of 1606 subjects were included. During a mean follow-up of 35.9 months, there were 239 patients with eGFR >25% reduction and 60 patients with >50% reduction. In the Kaplan-Meier survival curve and log-rank test, increased levels of FABP-3 were significantly correlated with eGFR >25% reduction (p < .001) and >50% reduction (p < .001). Multivariate Cox regression model revealed that subjects with higher FABP-3 exhibited a greater risk of eGFR >25% reduction (Group 2: hazard ratio [HR] = 2.328, 95% confidence interval [CI] = 1.521-3.562, p < .001; Group 3: HR = 3.054, 95% CI = 1.952-4.776, p < .001) and >50% reduction (Group 3: HR = 4.838, 95% CI = 1.722-13.591, p = .003).

CONCLUSIONS

Serum FABP-3 may serve as a novel biomarker to predict eGFR decline in patients with chronic coronary syndrome.

Inter-organ crosstalk during development and progression of type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is characterized by tissue-specific insulin resistance and pancreatic β-cell dysfunction, which result from the interplay of local abnormalities within different tissues and systemic dysregulation of tissue crosstalk. The main local mechanisms comprise metabolic (lipid) signalling, altered mitochondrial metabolism with oxidative stress, endoplasmic reticulum stress and local inflammation. While the role of endocrine dysregulation in T2DM pathogenesis is well established, other forms of inter-organ crosstalk deserve closer investigation to better understand the multifactorial transition from normoglycaemia to hyperglycaemia. This narrative Review addresses the impact of certain tissue-specific messenger systems, such as metabolites, peptides and proteins and microRNAs, their secretion patterns and possible alternative transport mechanisms, such as extracellular vesicles (exosomes). The focus is on the effects of these messengers on distant organs during the development of T2DM and progression to its complications. Starting from the adipose tissue as a major organ relevant to T2DM pathophysiology, the discussion is expanded to other key tissues, such as skeletal muscle, liver, the endocrine pancreas and the intestine. Subsequently, this Review also sheds light on the potential of multimarker panels derived from these biomarkers and related multi-omics for the prediction of risk and progression of T2DM, novel diabetes mellitus subtypes and/or endotypes and T2DM-related complications.

Characteristics and predictors of low-grade renal artery stenosis in female patients with CKD

AIM

Renal artery stenosis (RAS) is an important cause of chronic kidney disease (CKD). The main purpose of this study was to explore the clinical characteristics and predictors of low-grade RAS in female patients with CKD.

METHODS

One hundred and five female CKD patients from Huadong Hospital affiliated with Fudan University who underwent 3 T non-contrast renal artery magnetic resonance angiography (MRA) were analyzed. Basic statistics methods were used in the study, such as independent-sample t test,non-parametric test, binary logistic regression analysis and ROC analysis.

RESULTS

In this cross-sectional study, there were 50 patients with RAS and 55 without RAS (47.6% versus 52.4%). Binary logistic regression analysis demonstrated that low-level ALB and lymphocyte count, high-level SP, BUN and NLR were independent risk factors for low-grade RAS in female patients with CKD. ROC analysis indicated that eGFR, FeNa and UBCR, ALB, lymphocyte count and NLR had the best predictive value for low-grade RAS, especially eGFR with a sensitivity of 65.50% and specificity of 72.00% and FeNa with a sensitivity of 71.10% and specificity of 72.20% and BUCR with a sensitivity of 71.10% and specificity of 68.10%.

CONCLUSION

In female patients with CKD, FeNa, eGFR, ALB, UBCR, lymphocyte count and NLR may be good predictors of low-grade RAS, especially eGFR, FeNa and BUCR.

Urinary PART1 and PLA2R1 Could Potentially Serve as Diagnostic Markers for Diabetic Kidney Disease Patients

Background

Diabetic kidney disease (DKD) is a chronic renal disease which could eventually develop into renal failure. Though albuminuria and estimated glomerular filtration rate (eGFR) are helpful for the diagnosis of DKD, the lack of specific biomarkers reduces the efficiency of therapeutic interventions.

Methods

Based on bulk-seq of 56 urine samples collected at different time points (including 11 acquired from DKD patients and 11 from healthy controls), in corporation of scRNA-seq data of urine samples and snRNA-seq data of renal punctures from DKD patients (retrieved from NCBI GEO Omnibus), urine-kidney specific genes were identified by Multiple Biological Information methods.

Results

Forty urine-kidney specific genes/differentially expressed genes (DEGs) were identified to be highly related to kidney injury and proteinuria for the DKD patients. Most of these genes participate in regulating glucagon and apoptosis, among which, urinary PART1 (mainly derived from distal tubular cells) and PLA2R1 (podocyte cell surface marker) could be used together for the early diagnosis of DKD. Moreover, urinary PART1 was significantly associated with multiple clinical indicators, and remained stable over time in urine.

Conclusion

Urinary PART1 and PLA2R1 could be shed lights on the discovery and development of non-invasive diagnostic method for DKD, especially in early stages.

Unveiling FOS as a Potential Diagnostic Biomarker and Emetine as a Prospective Therapeutic Agent for Diabetic Nephropathy

Background

Diabetic nephropathy (DN) is one of the primary causes of end-stage renal disease, yet effective therapeutic targets remain elusive. This study aims to identify novel diagnostic biomarkers and potential therapeutic candidates for DN.

Methods

Differentially expressed genes (DEGs) in GSE96804 and GSE142025 were identified and functional enrichment analysis was performed. Diagnostic biomarkers were selected using machine learning algorithms and evaluated by Receiver Operating Characteristic analysis. c-Fos expression was validated in an established DN mouse model. Immune infiltration levels were assessed with Single-Sample Gene Set Enrichment Analysis. Co-expression analysis revealed regulatory relationships involving FOS. cMAP predicted potential therapeutic candidates. Transcriptome sequencing and experiments in RAW264.7 cells was performed to investigate molecular mechanisms of emetine.

Results

In both datasets, we identified 44 upregulated and 74 downregulated DEGs involved in focal adhesion, ECM-receptor interaction, and the PI3K-Akt signaling pathway. FOS emerged as a robust diagnostic marker with decreased expression in DN patients and DN mouse. Co-expression analysis revealed potential regulatory mechanisms of FOS, implicating the MAPK signaling pathway, regulation of cell proliferation and apoptotic signaling pathways. Immune dysregulation was observed in DN patients. Notably, emetine was identified as a potential therapeutic candidate. Transcriptome sequencing and experimental validation demonstrated emetine suppressed M1 macrophage polarization by inhibiting the activation of NF-κB signaling pathway, as well as reducing the expression of Il-18 and Ccl5.

Conclusion

In conclusion, our study identified FOS as a promising diagnostic biomarker and emetine as a potential therapeutic candidate for DN. These findings enhance our understanding of DN pathogenesis and present novel prospects for therapeutic strategies.

Control Level of Type 2 Diabetes Mellitus in the Elderly Is Associated with Polypharmacy, Accompanied Comorbidities, and Various Increased Risks According to the Beers Criteria

Comorbidity rates in the geriatric population have increased because of rising life expectancy; thus, patients have had to use more medications. Type 2 diabetes mellitus, one of the most common diseases, may influence the number of drugs used in geriatric patients. The present study was designed to investigate the association between the level of type 2 DM and polypharmacy. Fifty patients with type 2 diabetes over the age of 65 were included according to the inclusion criteria; 23 were well-controlled and 27 had poorly controlled diabetes. The groups were similar in terms of age, sex, WBC, Hb, Plt, AST, ALT, serum creatinine, fasting glucose, and eGFR levels. Patients with HbA1c values above 7.5 were classified as poorly controlled diabetes patients, and those below were considered well-controlled diabetes patients and were evaluated for inappropriate medication use. The number of medications used daily by the cases (p < 0.001), the number of concomitant diseases (p = 0.001), and the number of increased risks according to the Beers Criteria (p = 0.02) were observed to be high in poorly controlled type 2 diabetes mellitus subjects. HbA1c levels were related to the number of medications (r = 0.4, p = 0.004), comorbidities (r = 0.28, p = 0.04), and the number of increased risks according to the Beers Criteria (r = 0.31, p = 0.014). In conclusion, the number of medications used in patients with poorly controlled type 2 diabetes mellitus was found to be more elevated than in individuals with well-controlled type 2 diabetes mellitus. The HbA1c values varied among patients regarding polypharmacy, comorbidities, and increased risks according to the Beers Criteria.

The role and mechanisms of microvascular damage in the ischemic myocardium

Following myocardial ischemic injury, the most effective clinical intervention is timely restoration of blood perfusion to ischemic but viable myocardium to reduce irreversible myocardial necrosis, limit infarct size, and prevent cardiac insufficiency. However, reperfusion itself may exacerbate cell death and myocardial injury, a process commonly referred to as ischemia/reperfusion (I/R) injury, which primarily involves cardiomyocytes and cardiac microvascular endothelial cells (CMECs) and is characterized by myocardial stunning, microvascular damage (MVD), reperfusion arrhythmia, and lethal reperfusion injury. MVD caused by I/R has been a neglected problem compared to myocardial injury. Clinically, the incidence of microvascular angina and/or no-reflow due to ineffective coronary perfusion accounts for 5-50% in patients after acute revascularization. MVD limiting drug diffusion into injured myocardium, is strongly associated with the development of heart failure. CMECs account for > 60% of the cardiac cellular components, and their role in myocardial I/R injury cannot be ignored. There are many studies on microvascular obstruction, but few studies on microvascular leakage, which may be mainly due to the lack of corresponding detection methods. In this review, we summarize the clinical manifestations, related mechanisms of MVD during myocardial I/R, laboratory and clinical examination means, as well as the research progress on potential therapies for MVD in recent years. Better understanding the characteristics and risk factors of MVD in patients after hemodynamic reconstruction is of great significance for managing MVD, preventing heart failure and improving patient prognosis.

Correlation Between Glycemic Variability and Diabetic Complications: A Narrative Review

Diabetes mellitus is a metabolic disorder with a complex etiology in which glycemic dynamics are disturbed and the body is unable to maintain the process of glucose homeostasis through the pancreas. Persistent symptoms of high blood glucose or low blood glucose may lead to diabetic complications, such as neuropathy, nephropathy, retinopathy, and cardiovascular diseases. Glycemic variability which can represent the presence of excessive glycemic excursions is an indicator for evaluating glucose homoeostasis. Limiting glycemic variability has gradually become an emerging therapeutic target in improve diabetes metabolism and prevent associated complications. This article reviews the progress of research on the various quantifiable parameters of glycemic variability and their relationships with vascular lesions and mechanisms.

Evaluation of Hepatic/Renal and Splenic/Renal Echointensity Ratio Using Ultrasonography in Diabetic Nephropathy

The objective of this study is to assess the hepatic/renal and splenic/renal echointensity ratios in ultrasonography in patients with and without diabetic nephropathy. This retrospective study included patients with diabetes mellitus who underwent ultrasound examinations at our hospital between January 2023 and May 2023. Ultrasound examinations were conducted using renal cortical echogenicity and corticomedullary differentiation by using B-mode ultrasonography. The hepatic/renal and splenic/renal echo intensity ratios were compared among study groups (diabetic patients with diabetic nephropathy and without nephropathy). The diabetic nephropathy group exhibited significantly higher right renal echointensity and left renal echointensity compared to the non-nephropathic group. Additionally, the splenic/renal echointensity ratio and hepatic/renal echointensity ratio were significantly lower in the diabetic nephropathy group. Urinary microalbumin levels were significantly correlated with right renal echointensity (r = 0.65, p < 0.001) and left renal echointensity (r = 0.69, p < 0.001). There was also a significant inverse correlation between the urinary albumin and splenic/renal echointensity ratio (r = -0.58, p < 0.001). Ultrasonography, specifically the assessment of hepatic/renal and splenic/renal echointensity ratios, shows promise as a noninvasive and cost-effective method for evaluating morphological changes in the kidneys in patients with diabetic nephropathy. These findings suggest that ultrasonography can be a valuable tool for monitoring the progression of diabetic nephropathy and contributing to its early detection and management.

Association of Serum Bile Acid and Unsaturated Fatty Acid Profiles with the Risk of Diabetic Retinopathy in Type 2 Diabetic Patients

Aim

We aimed to identify the ability of serum bile acids (BAs) and unsaturated fatty acids (UFAs) profiles to predict the development of diabetic retinopathy (DR) in type 2 diabetes mellitus (T2DM) patients.

Methods

We first used univariate and multivariate analysis to compare 15 serum BA and 11 UFA levels in healthy control (HC) group (n = 82), T2DM patients with DR (n = 58) and T2DM patients without DR (n = 60). Forty T2DM patients were considered for validation. Then, the receiver operating characteristic curve (ROC) and decision curve analysis were used to assess the diagnostic value and clinical benefit of serum biomarkers alone, clinical variables alone or in combination, and the area under the curve (AUC), integrated discrimination improvement (IDI), and net reclassification improvement (NRI) were used to further assess whether the addition of biomarkers significantly improved the predictive ability of the model.

Results

Orthogonal partial least squares-discriminant analysis (OPLS-DA) of serum BAs and UFAs separated the three cohorts including HC, T2DM patients with or without DR. The difference in serum BA and UFA profiles of T2DM patients with or without DR was mainly manifested in the three metabolites of taurolithocholic acid (TLCA), tauroursodeoxycholic acid (TUDCA) and arachidonic acid (AA). Together, they had an AUC of 0.785 (0.918 for validation cohort) for predicting DR in T2DM patients. After adjusting for numerous confounding factors, TLCA, TUDCA, and AA were independent predictors that differentiated T2DM with or without DR. The results of AUC, IDI, and NRI demonstrated that adding these three biomarkers to a model with clinical variables statistically increased their predictive value and were replicated in our independent validation cohort.

Conclusion

These findings highlight the association of three metabolites, TLCA, TUDCA and AA, with DR and may indicate their potential value in the pathogenesis of DR.

Serum Isthmin-1 Was Increased in Type 2 Diabetic Patients but Not in Diabetic Sensorimotor Peripheral Neuropathy

Purpose

This study aimed to investigate the relationship between serum isthmin-1 (ISM1) and type 2 diabetes mellitus (T2DM), and the alteration of serum ISM1 level in both diabetic sensorimotor peripheral neuropathy (DSPN) and diabetic adults with obesity.

Patients and Methods

We recruited 180 participants (120 T2DM and 60 controls) in the cross-sectional study. First, we compared the serum ISM1 concentration in diabetic patients and non-diabetic controls. Secondly, according to DSPN, patients were divided into DSPN and non-DSPN groups. Last, patients were categorized as lean T2DM (15 males, 15 females), overweight T2DM (35 males, 19 females), and obese T2DM groups (23 males, 13 females) according to gender and body mass index (BMI). All participants were collected with clinical characteristics and biochemical profiles. Serum ISM1 was detected in all subjects by ELISA.

Results

Higher serum ISM1 [7.78 ng/mL (IQR: 6.33-9.06) vs 5.22 (3.86-6.04), P <0.001] was observed in diabetic patients compared to non-diabetic controls. Binary logistic regression analysis showed that serum ISM1 was a risk factor for type 2 diabetes after adjustment (OR=4.218, 95% CI: 1.843-9.653, P=0.001). Compared to the non-DSPN group, serum ISM1 level was not changed significantly in patients who suffered from DSPN. Diabetic females with obesity had lower level of serum ISM1 (7.10±1.29 ng/mL) when compared to the lean T2DM (8.42±1.36 ng/mL, P <0.05) and the overweight T2DM (8.33±1.27 ng/mL, P <0.05). However, serum ISM1 was not changed significantly in male groups or all patients together.

Conclusion

Serum ISM1 was a risk factor for type 2 diabetes, and it was associated with diabetic adults with obesity while there was sexual dimorphism. However, serum ISM1 levels were not correlated with DSPN.

Potential impact of epicardial fat thickness, pentraxin-3, and high-sensitive C-reactive protein on the risk of non-proliferative diabetic retinopathy

Purpose

We tried to clarify the potential association between systemic inflammatory markers like high-sensitive C-reactive protein (Hs-CRP), pentraxin-3 (PTX3), and epicardial fat thickness (EFT) with the non-proliferative diabetic retinopathy (NPDR) in patients with type 2 diabetes mellitus (T2D). Previous studies dealt with diabetic retinopathy as a whole entity rather than early stages of diabetic retinopathy. Early detection of various determinants of NPDR is prioritized in clinical practice.

Methods

A case-control study was conducted at Mansoura University Hospital, included 207 Egyptian subjects divided into 3 groups; 69 diabetic patients without retinopathy, 69 diabetic patients with NPDR, and 69 healthy control subjects. Participants were subjected to clinical history taking, physical examination, and laboratory assessment of Hs-CRP and plasma PTX3. Transthoracic echocardiography was applied to estimate EFT.

Results

Hs-CRP, PTX3, and EFT were significantly higher in patients with T2D without retinopathy than control cohort (p = 0.033, p < 0.00 and p < 0.00, respectively). Moreover, patients with NPDR showed significantly higher values of Hs-CRP, PTX3, and EFT than diabetic comparators without retinopathy (p = 0.002, p = 0.012, and p < 0.001, respectively). Although, NPDR was positively correlated with Hs-CRP, PTX3, and EFT (p < 0.001), Hs-CRP was not an independent determinant of NPDR meanwhile, EFT (OR = 1.094, 95%CI: 1.036-1.154, P = 0.001) and PTX3 (OR = 16.145, 95%CI: 1.676-155.551, P = 0.016) were.

Conclusion

Plasma pentraxin-3 and epicardial fat thickness showed more significant association with NPDR than high-sensitive C-reactive protein in patients with type 2 diabetes mellitus.

Association between P300 parameters and cognitive function in people with diabetic neuropathy

Purpose

The purpose of this study was to investigate the association between event-related potential (ERP) P300 with cognitive function in people with diabetic peripheral neuropathy (DPN).

Methods

We performed a cross-sectional analysis of 19 type 2 diabetes mellitus (T2DM) patients, aged 18 and older with DPN. The participants were assessed for neuropathy, cognitive function, & dual-task performance. DPN was examined via the administration of diabetic neuropathy symptom score (DNSS) and vibration perception threshold (VPT). Cognitive dysfunction was evaluated using Mini-mental state examination (MMSE), trail making test-B (TMT-B), and ERP P300 wave latency & amplitude. For assessing dual-task performance, the dual-task cost (DTC) was calculated using the timed-up and go (TUG) test and TUG with dual task (TUG-DT).

Results

P300 latency was linearly related to TMT-B (R = 0.31, p = 0.01) and DTC (R = 0.22, p = 0.04). A similar trend was observed in TMT-B (R = 0.13, p = 0.04) & DTC (R =0 .67, p = 0.001) with respect to P300 amplitude. MMSE did not relate with P300 latency (R = 0.14, p = 0.58) & amplitude (R = 0.63, p = .44).

Conclusion

P300 latency and amplitude are associated with cognitive function and DTC of individuals with DPN.

Evaluation of Nrg4 and thiol/disulfide homeostasis in patients with GDM

BACKGROUND

In this study, we aimed to evaluate the role of neuregulin4 (Nrg4) in the etiopathogenesis of gestational diabetes mellitus (GDM) and thiol/disulfide homeostasis as an indicator of oxidative stress.

METHODS

This prospective, case-control study included 34 women with diabetes and 34 healthy pregnant women who applied between January 2017 and January 2020. Levels of native and total thiol, disulfide and Nrg4 were measured in both diabetes mellitus and healthy pregnant groups.

RESULTS

When compared to the control group, the serum neuregulin4 levels in the diabetes group were considerably lower (3.22 ± 2.16 vs. 4.55 ± 0.96, p < 0.001). Native thiol (292.67 ± 43.65 vs. 366.40 ± 51.28; p < 0.001), total thiol (388.60 ± 46.60 vs. 414.52 ± 54.19; p < 0.001) levels and native thiol/total thiol ratio (75.51 ± 8.95 vs. 88.35 ± 3.54; p < 0.001) were lower in diabetes group compared to control group. Disulfide level (47.96 ± 19.52 vs. 24.06 ± 7.69) and disulfide/native thiol (17.13 ± 8.03, vs. 6.67 ± 2.30) and disulfide/total thiol (12.24 ± 4.47 vs. 5.82 ± 1.77) ratios were higher in diabetes group (all p < 0.001).

CONCLUSIONS

We suggested that decreased Nrg4 level and impaired oxidative stress parameters may be related with the increased risk of diabetes. However, we did not found a correlation between the Nrg4 and oxidative stress parameters.

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.

Prevalence and association of diabetic nephropathy in newly diagnosed Chinese patients with diabetes in the Hebei province: A single-center case-control study

Diabetes is a chronic disease and has huge pressure on patients and the medical system, especially for patients with diabetic complications, for example, diabetic nephropathy. Diabetic nephropathy is a diabetic complication associated with damage to the kidney. To improve the quality of life of patients with diabetes, it is necessary to understand the factors that are associated with diabetic nephropathy. The objective of the study was to find the prevalence of diabetic nephropathy in newly diagnosed patients with diabetes and to develop the association between clinicopathological parameters and diabetic nephropathy. In a case-control study, demographics, anthropometric, and clinicopathological parameters of a total of 305 newly diagnosed patients with diabetes (the fasting blood glucose ≥ 7.0 mM/L and/or glycosylated hemoglobin ≥ 6.5 mM/L) in Hebei province were included in the analysis. If the urine albumin to creatinine ratio was ≥ 30 (microalbuminuria) then patients were considered diabetic nephropathy. Among enrolled patients, 206 (68%) were males and 99 (32%) were females and they were 46 to 71 years old. Demographic variables and health-related behaviors were the same among patients with diabetes either with nephropathy (case group, n = 135) or patients without nephropathy (control group, n = 170, P > .05 for all). The prevalence of diabetic nephropathy was 44%. Female to male ratio was 1:1.7 in the case group. Patients with diabetic nephropathy had higher body weight (P < .0001), waist circumference (P = .0006), and body mass index (P = .0002) than those of patients without nephropathy. Abnormal urinary globulin (P = .041, odd ratio (OR): 1.1231) was associated with diabetic nephropathy. Aspartate transaminase (P = .0651, OR: 0.8541), alkaline phosphatase (P = .0661, OR: 0.8122), hypertension (P = .0821, OR: 0.8214), and blood urea nitrogen (P = .0842, OR: 0.9411) were not significantly associated with diabetic neuropathy. However, they are near the statistical cutoff value. The prevalence of diabetic nephropathy in newly diagnosed diabetic patients of Hebei province is higher than those of the other provinces. Urinary globulin excretion had a weak association with the presence of nephropathy defined by urinary albumin excretion in patients with diabetes. The presence of other diabetic complications is also an essential parameter for diabetic nephropathy. Males are more susceptible to diabetic nephropathy than females if diabetic (Evidence Level: V; Technical Efficacy: Stage 3).

Evaluation of serum levels of Irisin as a marker of endothelial dysfunction in patients with type 2 diabetes mellitus

INTRODUCTION

Insulin resistance and obesity have been associated with irisin, a protein in fat cells. The levels of irisin in patients with type 2 diabetes mellitus (T2DM) were significantly lower than those in non-diabetics. This study aimed to examine the relationship between serum irisin levels and endothelial dysfunction in patients with T2DM.

METHODS

There were 90 participants in this study. We matched 65 patients with T2DM with 25 healthy control participants. A series of tests were performed on the participants, including fasting blood glucose, 2 hours postprandial blood glucose, glycated haemoglobin, triglycerides (TG), total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), TG/HDL-C ratio and albumin/creatinine ratio. In addition to measuring high-sensitivity C-reactive protein (hs-CRP). Enzyme-linked immunosorbent assay (ELISA) technique was used for estimating irisin concentrations.

RESULTS

Flow-mediated dilation (FMD) was significantly lower in patients with T2DM; however, there was a non-statistically significant difference between healthy controls and patients with T2DM regarding serum Irisin level. CRP and LDL levels were inversely correlated with circulating irisin levels. In a stepwise regression analysis, only the hs-CRP and LDL were statistically significant in predicting irisin level.

CONCLUSIONS

In patients with T2DM, serum levels of irisin were inversely correlated with hyperglycaemia, body mass index and per cent body fat; this suggests that detecting irisin levels early can prevent cardiovascular diseases from progressing. According to the study results, serum irisin serves as a predictive marker for early cardiovascular disease, thus preventing the disease from progressing. There is a need for further research in order to understand how irisin contributes to the development of atherosclerosis and the development of diabetic complications.

Emerging Therapy for Diabetic Cardiomyopathy: From Molecular Mechanism to Clinical Practice

Diabetic cardiomyopathy is characterized by abnormal myocardial structure or performance in the absence of coronary artery disease or significant valvular heart disease in patients with diabetes mellitus. The spectrum of diabetic cardiomyopathy ranges from subtle myocardial changes to myocardial fibrosis and diastolic function and finally to symptomatic heart failure. Except for sodium–glucose transport protein 2 inhibitors and possibly bariatric and metabolic surgery, there is currently no specific treatment for this distinct disease entity in patients with diabetes. The molecular mechanism of diabetic cardiomyopathy includes impaired nutrient-sensing signaling, dysregulated autophagy, impaired mitochondrial energetics, altered fuel utilization, oxidative stress and lipid peroxidation, advanced glycation end-products, inflammation, impaired calcium homeostasis, abnormal endothelial function and nitric oxide production, aberrant epidermal growth factor receptor signaling, the activation of the renin–angiotensin–aldosterone system and sympathetic hyperactivity, and extracellular matrix accumulation and fibrosis. Here, we summarize several important emerging treatments for diabetic cardiomyopathy targeting specific molecular mechanisms, with evidence from preclinical studies and clinical trials.

Association of high-sensitivity C-reactive protein and diabetic nephropathy in patients with type 2 diabetes: a Mendelian randomization study

INTRODUCTION

Observational studies support the relationship between C-reactive protein (CRP) level and diabetic nephropathy (DN) in patients with diabetes. The research question regarding whether the relationship between serum high-sensitivity C-reactive protein (hsCRP) level and DN is causal lacks experimental evidence. Therefore, this study aimed to evaluate the causality between hsCRP and DN based on Mendelian randomization (MR) analysis.

RESEARCH DESIGN AND METHODS

A total of 2332 participants with type 2 diabetes from the Taiwan Biobank database was analyzed. Genetic risk scores (GRSs), which comprise four validated CRP loci as two instrumental variables, were calculated as unweighted and weighted scores to evaluate the causal relationship of hsCRP with DN risk. The two-stage regression model was used to estimate OR and 95% CI.

RESULTS

The analyses of the observational study showed that the hsCRP level was significantly associated with DN after multivariate adjustment (adjusted OR 1.15; 95% CI 1.01 to 1.32). Unweighted/weighted GRSs for log-transformed hsCRP satisfied MR assumptions 1 and 3, respectively; that is, a significant association with hsCRP was observed but that with DN was absent (adjusted OR 1.00, 95% CI 0.92 to 1.09; 1.00, 0.72 to 1.39, respectively). The MR analyses demonstrated that a 1-unit increase in the log-transformed genetically predicted hsCRP by unweighted and weighted GRSs was associated with DN, demonstrating ORs of 1.80 (95% CI 1.51 to 2.14) and 1.67 (95% CI 1.40 to 1.98), respectively.

CONCLUSIONS

The current study provided experimental evidence that hsCRP level was causally related to DN. These findings suggest that the elevated hsCRP may be a causal risk factor for DN in patients with type 2 diabetes.

Neuregulin 4 as a novel adipokine in energy metabolism

Adipose tissue has been shown to play a key role in energy metabolism and it has been shown to regulate metabolic homeostasis through the secretion of adipokines. Neuregulin 4 (Nrg4), a novel adipokine secreted mainly by brown adipose tissue (BAT), has recently been characterized as having an important effect on the regulation of energy homeostasis and glucolipid metabolism. Nrg4 can modulate BAT-related thermogenesis by increasing sympathetic innervation of adipose tissue and therefore has potential metabolic benefits. Nrg4 improves metabolic dysregulation in various metabolic diseases such as insulin resistance, obesity, non-alcoholic fatty liver disease, and diabetes through several mechanisms such as anti-inflammation, autophagy regulation, pro-angiogenesis, and lipid metabolism normalization. However, inconsistent findings are found regarding the effects of Nrg4 on metabolic diseases in clinical settings, and this heterogeneity needs to be further clarified by future studies. The potential metabolic protective effect of Nrg4 suggests that it may be a promising endocrine therapeutic target.

Effect of intensive lifestyle intervention on the association between weight variability and major adverse cardiovascular events in overweight or obese adults with type 2 diabetes mellitus

AIMS/INTRODUCTION

Weight variability is associated with cardiovascular outcomes in diabetic patients. However, whether the guideline-recommended intensive lifestyle intervention (ILI) will affect this association in overweight or obese adults with diabetes is not well established.

MATERIALS AND METHODS

In 3,859 participants from the Action for Health in Diabetes (Look AHEAD) trial, the associations of 4 year weight variability measured by variability independent of the mean (VIM) with major adverse cardiovascular event (MACE) and secondary outcomes in ILI and diabetes support & education (DSE) arm were evaluated.

RESULTS

During a median follow-up of 9.6 years, 255 (12.9%) participants in the ILI arm and 247 (13.2%) participants in the DSE arm developed MACE. Participants with the highest quartile of weight variability (VIM Q4) experienced a 2.23-fold higher risk of MACE compared with the lowest quartile (VIM Q1) in the DSE arm (hazard ratio [HR] 2.23; 95% CI 1.51-3.30). Compared with the lowest weight variability (VIM Q1), participants with the highest weight variability (VIM Q4) were associated with higher risks of secondary cardiovascular composite outcome (HR 1.88; 95% CI 1.20-2.95), all-cause mortality (HR 3.19; 95% CI 1.75-5.82), and myocardial infarction (HR 1.95; 95% CI 1.12-3.37) in the DSE arm.

CONCLUSIONS

Among the overweight or obese individuals with type 2 diabetes mellitus, rising weight variability was independently associated with increased MACE risks in the DSE arm. Therefore, a guideline-recommended ILI strategy for weight loss should be adopted to improve cardiovascular outcomes without worrying about the effect of weight fluctuations.

Ferulic acid enhances insulin secretion by potentiating L-type Ca2+ channel activation

OBJECTIVE

To investigate the effect of ferulic acid, a natural compound, on pancreatic beta cell viability, Ca²⁺ channels, and insulin secretion.

METHODS

We studied the effects of ferulic acid on rat insulinoma cell line viability using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide viability assay. The whole-cell patch-clamp technique and enzyme-linked immunosorbent assay were also used to examine the action of ferulic acid on Ca²⁺ channels and insulin secretion, respectively.

RESULTS

Ferulic acid did not affect cell viability during exposures up to 72 h. The electrophysiological study demonstrated that ferulic acid rapidly and concentration-dependently increased L-type Ca²⁺ channel current, shifting its activation curve in the hyperpolarizing direction with a decreased slope factor, while the voltage dependence of inactivation was not affected. On the other hand, ferulic acid have no effect on T-type Ca²⁺ channels. Furthermore, ferulic acid significantly increased insulin secretion, an effect inhibited by nifedipine and Ca²⁺-free extracellular fluid, confirming that ferulic acid-induced insulin secretion in these cells was mediated by augmenting Ca²⁺ influx through L-type Ca²⁺ channel. Our data also suggest that this may be a direct, nongenomic action.

CONCLUSION

This is the first electrophysiological demonstration that acute ferulic acid treatment could increase L-type Ca²⁺ channel current in pancreatic β cells by enhancing its voltage dependence of activation, leading to insulin secretion.

Association Between Uric Acid to HDL Cholesterol Ratio and Diabetic Complications in Men and Postmenopausal Women

AIM

Previous studies have implicated the uric acid to high-density lipoprotein cholesterol (HDL-C) ratio (UHR) was associated with type 2 diabetes. However, the association between UHR and diabetes-related vascular damages is still unclear.

METHODS

The total of 4551 patients with type 2 diabetes from the cross-sectional Environmental Pollutant Exposure and Metabolic Diseases in Shanghai study (METAL study) were enrolled. UHR was calculated as uric acid to HDL-C ratio. Cardiovascular disease (CVD) was defined as previously diagnosed with stroke, coronary heart disease, or peripheral arterial disease. Chronic kidney disease (CKD) was defined as estimated glomerular filtration rate ≤60 mL/min/1.73 m² and/or urinary albumin to creatinine ratio ≥30 mg/g. Fundus image was examined by trained individuals and degree of diabetic retinopathy (DR) was evaluated.

RESULTS

UHR was positively correlated with CVD (OR = 1.28, 95% CI: 1.02-1.61) and CKD (OR = 1.78, 95% CI: 1.39-2.27) after adjusting for all confounders. No association was found between UHR and DR. In stratified analyses, UHR was predominantly correlated with CVD in diabetic patients with age older than 65 (OR = 1.41, 95% CI: 1.08-1.85), female (OR = 1.43, 95% CI: 1.06-1.94) and BMI≥24kg/m² (OR = 1.57, 95% CI: 1.17-2.11). A 1-SD increment of UHR was also positively associated with CVD (OR 1.26, 95% CI 1.03, 1.15) and CKD (OR 1.28, 95% CI 1.20,1.39). UHR was positively associated with CKD in all subgroups analysis. No significant interaction effect was observed between UHR and all subgroup variables in CVD and CKD risk.

CONCLUSION

Our study reported a positive association between the UHR and diabetic-related vascular complications in men and postmenopausal women. The relationship between the UHR and DR seems to be uncertain and requires further investigation. And no significant interaction effect was observed between the UHR and all subgroup variables in CVD and CKD risk.

The feasibility and efficacy of a community-based multifactorial intervention to improve the cardiovascular risk factor control among patients with type 2 diabetes: A 2-year cluster randomized trial

TRIAL DESIGN

Our study is to investigate the feasibility and effectiveness of multiple cardiovascular factors intervention (MFI) in type 2 diabetes patients in China's primary care setting.

METHODS

We performed a cluster randomized trial to compare the proportion of patients achieved the targets between usual care group (control, 9 sites, n = 868) and MFI group (8 sites, n = 739) among patients with type 2 diabetes in primary care setting. Logistic regression model with random effects was used to estimate the association of the effect of intervention and the proportion achieved the targets.

RESULTS

At baseline, the end of 1 year, and 2 years follow-up, the proportion of patients achieved all 3 target goals (HbA1c < 7.0%, blood pressure < 130/80 mm Hg and low-density lipoprotein cholesterol < 2.6 mmol/L) were 5.7%, 5.9%, 5.7% in the control group and 5.9%, 10.6%, 12.3% in the MFI group. After adjusting sex, age, diabetes duration, body mass index, HbA1c, blood pressure, and low-density lipoprotein cholesterol at baseline, there was no difference between the 2 groups (OR (95% CI): 1.27 (0.38-4.27) and 1.86 (0.79-4.38) for the first year and second year, respectively). When stratified by payment method, the patients with medical insurance or public expenses had a higher proportion achieved target goals (6.9% vs 16.4%, OR (95% CI): 2.30 (1.04-5.08)) in the second year.

CONCLUSIONS

The controlling of cardiovascular risk factor targets remains suboptimal among patients with type 2 diabetes in primary care setting. MFI in type 2 diabetes improved cardiovascular disease risk profile, especially in the patients with medical insurance.

Detection value of FOXO1 gene methylation, blood glucose and lipids in patients with type 2 diabetic kidney disease

Forkhead transcription factor O1 (FOXO1) methylation is associated with inflammation. Diabetic kidney disease (DKD) is characterized with increased inflammatory markers such as uric acid, hemogram indices, C-reactive protein derived markers, omentin and neuregulin. This study aimed to investigate the effect of DNA methylation in FOXO1 gene promoter, blood glucose and lipids in the process of type 2 DKD. Bisulfite genomic sequencing was used to monitor DNA methylation in the promoter region (+1021, +1193) of FOXO1 gene. The detections were taken in glycosylated hemoglobin A1c, fasting plasma glucose and blood lipid. 81 participants were divided into the control group, the preliminary diabetes mellitus group, the pure diabetes mellitus group, and the DKD group. The other groups displayed higher fasting plasma glucose than the control group (all P value < .05). The fasting plasma glucose level was higher in the pure diabetes mellitus group than the preliminary diabetes mellitus group (P = .004). The levels of HbA1c were higher in other groups than control group and preliminary diabetes mellitus groups (all P values < .01). The high-density lipoprotein level was lower in the DKD group (P = .021, P = .022) than control and pure diabetes mellitus group. The levels of low-density lipoprotein were statistically lower in preliminary diabetes mellitus and DKD groups than control group (all P value < .02). Along with the progress of DKD, a down trend was observed in the total methylation rate of FOXO1 gene (P = .025), which contains 5 CpG sites (1021, +1193) in the promoter. Hypomethylation in the promoter of FOXO1 gene, hyperglycemia and low level of serum lipid might be associated with the pathogenesis of type 2 DKD.

Ferroptosis and renal fibrosis: A new target for the future (Review)

Ferroptosis is a type of non-apoptotic controlled cell death triggered by oxidative stress and iron-dependent lipid peroxidation. Ferroptosis is regulated by signalling pathways that are associated with metabolism, including glutathione peroxidase 4 dysfunction, the cystine/glutamate antiporter system, lipid peroxidation and inadequate iron metabolism. Ferroptosis is associated with renal fibrosis; however, further research is required to understand the specific molecular mechanisms involved. The present review aimed to discuss the known molecular mechanisms of ferroptosis and outline the biological reactions that occur during renal fibrosis that may be associated with ferroptosis. Further investigation into the association between ferroptosis and renal fibrosis may lead to the development of novel treatment methods.

Metabolic outcomes in patients with type 2 diabetes mellitus after metabolic management center

The Chinese Medical Doctor Association has initiated metabolic management center (MMC) program for 6 years since 2016 nationwide. It is worth investigating the level of control metabolic outcomes in patients with type2 diabetes (T2DM) after MMC model in Yan'an, northwest China. Patients with T2DM was admitted to MMC in Yan'an University Affiliated Hospital from November 2018 to July 2021. They were asked to revisit hospital every 3 months. Blood glucose, blood pressure and blood lipids at baseline were compared to its counterparts after 1 year MMC management. Glycosylated hemoglobin and low density lipoprotein cholesterol (LDL-C) level in T2DM patients after 1 year management were lower than their baseline level (glycosylated hemoglobin 7.74 ± 1.94% vs 8.63 ± 2.26%, P < .001; LDL-C 1.81 ± 0.73mmol/L vs 2.18 ± 1.49mmol/L, P < .001). Mean HOMA-β increased after management (65.89 ± 90.81% vs 128.38 ± 293.93%, P < .05). After 1 year of management, patients in high school or above group achieved higher control rate of body mass index than those in middle school or below group (71.82% vs 28.18%, P = .043). high density lipoprotein cholesterol control rate was higher in high income group (42.86% vs 34.97%, 16.28%, P = .012), while LDL-C control rate was higher in low-income group (97.67% vs 78.57%, 84.51%, P = .018). fasting plasma glucose control rate in new diagnosis group was higher than that of the middle and long course groups (71.43% vs 52.38%, 42.44%, P = .002). The comprehensive control rate increased from 9.83% at baseline to 26.15% after 1 year MMC management. The metabolic outcomes and their control rate in T2DM patients were improved after 1 year MMC management. It indicated that patients may achieve more benefits with MMC management.

Association of serum leptin and insulin levels among type 2 diabetes mellitus patients: A case-control study

Secretion of insulin is compromised in type 2 diabetes (T2DM) individuals and inadequate to accommodate for insulin resistance (IR) in peripheral tissue. Hyperleptinemia reflects leptin resistance, which is a key factor in the production of IR in T2DM patients, making leptin a potential biomarker for evaluating IR levels. The objective of the study was to assess the association of serum leptin and insulin levels among T2DM patients. This case-control research was carried out on T2DM patients. A total of 73 patients diagnosed with T2DM (the case group) and 40 healthy participants (control; group 3) were enrolled according to the American Diabetes Association (ADA) criteria. In the case group, T2DM patients were enrolled with metabolic syndrome (group 1, n = 38) or without metabolic syndrome (group 2, n = 35) according to the WHO criteria. Metabolic profiles of T2DM patients with or without metabolic syndrome were evaluated, and compare these two groups with healthy controls. The subjects of all groups were age- and gender-matched. Body mass index (BMI, P < .01), fasting (P = .0133) and postprandial (P < .01) blood sugar levels, % glycated hemoglobin (HbA1c, P < .01), and lipid profile (P < .01) were found significantly different and higher in group 1 as compared to groups 2 and 3. Serum leptin and insulin levels were found higher and significant in patients with metabolic syndrome (P < .01 for both). The values of serum leptin levels were 10.01 ± 2.7 ng/mL, 6.9 ± 2.4 ng/mL, and 4.11 ± 1.8 ng/mL, and those of serum insulin 120 ± 40.7 µIU/mL, 20.43 ± 5.2 µIU/mL, and 11.4 ± 2.5 µIU/mL in groups 1, 2, and 3, respectively. There was a positive linear correlation between BMI, blood sugar, HbA1c, serum cholesterol (TC), and triglycerides (TG) with serum insulin and leptin levels in the case group. An extremely significant correlation (R = 0.74, P < .001) was found in BMI and serum leptin level in the case group. Serum leptin and insulin levels have a positive association, with serum leptin being a significant predictor of IR syndrome (Evidence Level: 5; Technical Efficacy: Stage 3).

Neuregulin-4 attenuates diabetic cardiomyopathy by regulating autophagy via the AMPK/mTOR signalling pathway

Background

Diabetic cardiomyopathy is characterized by left ventricle dysfunction, cardiomyocyte apoptosis, and interstitial fibrosis and is a serious complication of diabetes mellitus (DM). Autophagy is a mechanism that is essential for maintaining normal heart morphology and function, and its dysregulation can produce pathological effects on diabetic hearts. Neuregulin-4 (Nrg4) is an adipokine that exerts protective effects against metabolic disorders and insulin resistance. The aim of this study was to explore whether Nrg4 could ameliorate DM-induced myocardial injury by regulating autophagy.

Methods

Four weeks after the establishment of a model of type 1 diabetes in mice, the mice received Nrg4 treatment (with or without an autophagy inhibitor) for another 4 weeks. The cardiac functions, histological structures and cardiomyocyte apoptosis were investigated. Autophagy-related protein levels along with related signalling pathways that regulate autophagy were evaluated. In addition, the effects of Nrg4 on autophagy were also determined in cultured primary cardiomyocytes.

Results

Nrg4 alleviated myocardial injury both in vivo and in vitro. The autophagy level was decreased in type 1 diabetic mice, and Nrg4 intervention reactivated autophagy. Furthermore, Nrg4 intervention was found to activate autophagy via the AMPK/mTOR signalling pathway. Moreover, when autophagy was suppressed or the AMPK/mTOR pathway was inhibited, the beneficial effects of Nrg4 were diminished.

Conclusion

Nrg4 intervention attenuated diabetic cardiomyopathy by promoting autophagy in type 1 diabetic mice. Additionally, Nrg4 induced autophagy via the AMPK/mTOR signalling pathway.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01643-0.

Serum neuregulin 4 is negatively correlated with insulin sensitivity in humans and impairs mitochondrial respiration in HepG2 cells

Neuregulin 4 (NRG4) has been described to improve metabolic disturbances linked to obesity status in rodent models. The findings in humans are controversial. We aimed to investigate circulating NRG4 in association with insulin action in humans and the possible mechanisms involved. Insulin sensitivity (euglycemic hyperinsulinemic clamp) and serum NRG4 concentration (ELISA) were analysed in subjects with a wide range of adiposity (n = 89). In vitro experiments with human HepG2 cell line were also performed. Serum NRG4 was negatively correlated with insulin sensitivity (r = −0.25, p = 0.02) and positively with the inflammatory marker high-sensitivity C reative protein (hsCRP). In fact, multivariant linear regression analyses showed that insulin sensitivity contributed to BMI-, age-, sex-, and hsCRP-adjusted 7.2% of the variance in serum NRG4 (p = 0.01). No significant associations were found with adiposity measures (BMI, waist circumference or fat mass), plasma lipids (HDL-, LDL-cholesterol, or fasting triglycerides) or markers of liver injury. Cultured hepatocyte HepG2 treated with human recombinant NRG4 had an impact on hepatocyte metabolism, leading to decreased gluconeogenic- and mitochondrial biogenesis-related gene expression, and reduced mitochondrial respiration, without effects on expression of lipid metabolism-related genes. Similar but more pronounced effects were found after neuregulin 1 administration. In conclusion, sustained higher serum levels of neuregulin-4, observed in insulin resistant patients may have deleterious effects on metabolic and mitochondrial function in hepatocytes. However, findings from in vitro experiments should be confirmed in human primary hepatocytes.

Serum isthmin-1 levels are positively and independently correlated with albuminuria in patients with type 2 diabetes mellitus

INTRODUCTION

Isthmin-1 (Ism-1), as a novel adipokine, plays a role in glucose homeostasis and lipid metabolism. However, the relationship between Ism-1 and type 2 diabetes mellitus (T2DM) remains unclear. This study aims to investigate the association of serum Ism-1 levels with albuminuria and insulin resistance in patients with T2DM and preserved renal function.

RESEARCH DESIGN AND METHODS

A total of 150 patients with T2DM were recruited. The presence of albuminuria was evaluated by urinary albumin:creatinine ratio (UACR) in first morning urine sample. Serum Ism-1 levels were tested by ELISA. Homeostasis model assessments were used to evaluate insulin resistance. Binary logistic regression and multivariable linear regression analyses were used to assess the association of serum Ism-1 levels with albuminuria. Multivariable linear regression analyses were performed to explore the correlation of serum Ism-1 levels with insulin resistance.

RESULTS

Compared with the normal-albuminuria and microalbuminuria groups, serum Ism-1 levels were significantly higher in the macroalbuminuria group (p<0.01). Binary logistic regression analyses showed that serum Ism-1 was positively associated with odds of albuminuria even after multiple adjustments (OR=4.766, p=0.013). Serum Ism-1 was positively associated with log10-transformed UACR (β=0.625, p<0.001). However, the associations between serum Ism-1 levels and insulin resistance were not observed in patients with T2DM.

CONCLUSIONS

Serum Ism-1 levels were positively and independently correlated with the severity of albuminuria in patients with T2DM but not with insulin resistance.

Genetic Susceptibility to Insulin Resistance and Its Association with Estimated Longevity in the Hungarian General and Roma Populations

Diabetes mellitus is a major public health problem with a wide range of prevalence among different ethnic groups. Early recognition of pre-diabetes is important to prevent the development of the disease, its complications, co-morbidities, and consequently early death. Insulin resistance (IR) is considered a condition that precedes type 2 diabetes; thus, understanding its underlying causes (genetic and non-genetic factors) will bring us closer to preventing it. The present study aimed to investigate the genetic susceptibility to IR and its impact on estimated longevity in populations with different ethnic origins using randomly selected samples of 372 Hungarian general (HG, as a reference with Caucasian origin) and 334 Roma participants (largest ethnic minority in Europe, with a northern India origin). In the present study, we used the Homeostasis Model Assessment—Insulin Resistance (HOMA—IR) to identify people with IR (>3.63) at the population level. To investigate the genetic predisposition to IR, 29 single nucleotide polymorphisms (SNPs) identified in a systematic literature search were selected and genotyped in sample populations. In the analyses, the adjusted p < 0.0033 was considered significant. Of these 29 SNPs, the commutative effects of 15 SNPs showing the strongest association with HOMA—IR were used to calculate an optimized genetic risk score (oGRS). The oGRS was found nominally significantly (p = 0.019) higher in the Roma population compared to HG one, and it was more strongly correlated with HOMA—IR. Therefore, it can be considered as a stronger predictor of the presence of IR among the Roma (AUCRoma = 0.673 vs. AUCHG = 0.528). Furthermore, oGRS also showed a significant correlation with reduced estimated longevity in the Roma population (β = −0.724, 95% CI: −1.230−−0.218; p = 0.005), but not in the HG one (β = 0.065, 95% CI: −0.388−0.518; p = 0.779). Overall, IR shows a strong correlation with a genetic predisposition among Roma, but not in the HG population. Furthermore, the increased genetic risk of Roma is associated with shorter estimated longevity, whereas this association is not observed in the HG one. Increased genetic susceptibility of Roma to IR should be considered in preventive programs targeting the development of type 2 diabetes, which may also reduce the risk of preventable premature death among them.

Impact of red cell distribution width and red cell distribution width/albumin ratio on all-cause mortality in patients with type 2 diabetes and foot ulcers: a retrospective cohort study

Background

Red blood cell distribution width (RDW) has emerged as a prognostic factor for mortality in various diseases. Up to now, few studies have focused on the prognostic value of RDW in patients with diabetic foot ulcers (DFUs). This retrospective cohort study aimed to investigate the impact of RDW and RDW/albumin (ALB) ratio on all-cause mortality in patients with DFUs.

Methods

This study included 860 patients with DFUs in a tertiary academic hospital. The associations of RDW and RDW/ALB with all-cause mortality were assessed by multivariable cox regression analyses. The pairwise comparisons of receiver operating characteristic (ROC) curves were performed to compare the predictive performance of RDW and RDW/ALB ratio. Harrell’s concordance index, integrated discrimination improvement, and net reclassification improvement were used to estimate the improvements in risk discrimination.

Results

Patients with high RDW and RDW/ALB had lower overall survival rates (all P < 0.001). The multivariable Cox regression revealed that high RDW [adjusted hazard ratio (HR) 2.426, 95% confidence interval (CI): 1.557–3.778, P < 0.001] and high RDW/ALB (adjusted HR 2.360, 95% CI: 1.414–3.942, P = 0.001) were independent associated with high all-cause mortality. In subgroup analyses, the comparative analysis of ROC curves revealed that the discriminating ability of the RDW/ALB ratio was significantly superior to RDW in patients with no severe DFUs or no severe peripheral artery disease, or in young and middle-aged patients (all P < 0.05). Adding RDW and RDW/ALB ratio to base models improved discrimination and risk reclassification for all-cause mortality.

Conclusions

RDW and RDW/ALB ratio are robust and independent prognostic markers in patients with DFUs. The RDW/ALB ratio appears to be of more predictive value for mortality in younger and less severely ill patients with DFUs. Both RDW and RDW/ALB ratio can provide incremental predictive value for all-cause mortality over traditional risk factors. RDW and RDW/ALB ratio can be used to identify high-risk patients with DFUs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01534-4.

Associations between vitamin D status and sight threatening and non-sight threatening diabetic retinopathy: a systematic review and meta-analysis

Background

Vitamin D levels have been shown to be associated with diabetic retinopathy, however to date, no review has examined the relationship between vitamin D and sight threatening diabetic retinopathy (STDR) and non-sight threatening diabetic retinopathy (NSTDR). The aim of this review, therefore, was to pool associations between vitamin D deficiency (25(OH)D < 20 ng/mL) and STDR/NSTDR. A further aim was to examine associations between circulating 25(OH)D levels and STDR/NSTDR.

Methods

A systematic review of major databases was undertaken for studies published from inception to 22/04/2022, using a pre-published protocol. Studies reporting prevalence of STDR or NSTDR versus a control group with diabetes and no DR or DME and either (a) vitamin D deficiency prevalence, or (b) circulating 25(OH)D levels, were included. A random effects meta-analysis was undertaken.

Results

Following screening, 12 studies (n = 9057) were included in the meta-analysis. STDR was significantly associated with vitamin D deficiency (OR = 1.80 95%CI 1.40-2.30; p = <0.001), whereas NSTDR was not (OR = 1.07 95%CI 0.90-1.27; p = 0.48). Both conclusions were graded as low credibility of evidence. Furthermore, circulating 25(OH)D levels were significantly associated with both NSTDR (SMD = -0.27 95%CI -0.50; -0.04; p = 0.02) and STDR (SMD = -0.49 95%CI -0.90; -0.07; p = 0.02), although these were graded as low credibility of evidence.

Conclusion

Vitamin D deficiency is significantly associated with STDR (including DME), but not with NSTDR. Given the well-reported associations between vitamin D deficiency and other unfavourable outcomes, it is important that vitamin D deficiency is managed appropriately and in a timely manner to reduce the risk of blindness in people with diabetes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-022-01059-3.

Neuregulin 4 (NRG4) - the hormone with clinical significance in gestational diabetes mellitus

This study aimed at determining the association between serum neuregulin 4 (NRG4) and insulin in gestational diabetes mellitus (GDM) and their correlation with other metabolic parameters. A cross-sectional study was conducted from June 2018 to February 2019 at Ziauddin University, Karachi. Pregnant women (n = 80), at 24-28 weeks of gestation, were recruited. Demographic data, anthropometric measurements and antenatal history were recorded. The fasting blood was drawn for testing fasting blood sugar (FBS), NRG4, insulin and lipid profile. The subjects were evaluated for glucose challenge test after 50 g glucose ingestion. NRG4 levels (1.00 ± 0.15) were found significantly high (p < .04) in healthy group compared to GDM (0.95 ± 0.11). In GDM females, high levels for FBS (p < .02) and cholesterol (p < .03) were observed. Homeostatic model assessment of insulin resistance (HOMA-IR) had direct weak association with NRG4, inverse relationship with cholesterol and LDL but significant association (p < .05) with insulin. Significantly high NRG4 in healthy females suggests its potential role in regulating insulin sensitivity. Impact StatementWhat is already known on this subject? Neuregulin 4 (NGR4) is a batokine which plays a potential role in regulating insulin sensitivity, maintaining energy and metabolic homeostasis. Due to its role in lipid and glucose homeostasis, some studies report its role in gestational diabetes mellitus (GDM) but the results were controversial.What do the results of this study add? The study showed that NGR4 levels were significantly low in GDM subjects. Other metabolic factors especially insulin and homeostatic model assessment of insulin resistance (HOMA-IR) were found associated significantly (p < .05) with NGR4.What are the implications of these findings for clinical practice and/or further research? NGR4 can be a potential biomarker for gestational diabetes. Nevertheless, in order to confirm these findings, further studies, with bigger sample size are required to further ascertain the prospects of NRG4 as a potential biomarker for gestational diabetes.

Plasma C1q/tumor necrosis factor-related protein-3 concentrations are associated with diabetic peripheral neuropathy

INTRODUCTION

To analyze the associations of circulating C1q/tumor necrosis factor-related protein-3 (CTRP3) concentrations with several metabolic parameters and to investigate the possible role of CTRP3 in subjects with diabetic peripheral neuropathy (DPN).

RESEARCH DESIGN AND METHODS

A total of 347 participants were recruited in this study, and plasma CTRP3 concentrations were analyzed in subjects with DPN (n=172) and without DPN (non-DPN, n=175). The nerve conduction test and oral glucose tolerance test were performed, and Neuropathy Symptom Score (NSS)/Neuropathy Disability Score (NDS) and biochemical parameters were measured in all participants.

RESULTS

Plasma CTRP3 concentrations were significantly lower in patients with DPN compared with those in patients with diabetes without DPN (p<0.01), despite the comparable glucose and lipid metabolism levels in both groups. Groups with a higher plasma CTRP3 level had a faster nerve conduction velocity. In addition, plasma CTRP3 concentrations were negatively correlated with hemoglobin A1c (HbA1c), urea acid (UA), triglyceride, NSS and NDS (p<0.05) after being adjusted for age and sex. Multivariate logistic regression analysis revealed that plasma CTRP3 concentrations were significantly correlated with DPN after being controlled for age, sex, body mass index, HbA1c, blood pressure, lipid profiles, and renal function.

CONCLUSIONS

Plasma CTRP3 concentrations were significantly lower in patients with DPM and positively correlated with nerve conduction velocity. The relationship between CTRP3 levels and DPN is independent of the glucose and lipid status. Therefore, circulating CTRP3 might serve as a predictor of impairment of nerve conduction in patients with DPN.

Involvement of Cdkal1 in the etiology of type 2 diabetes mellitus and microvascular diabetic complications: a review

Diabetes Mellitus, being a polygenic disorder, have a set of risk genes involved in the onset of the insulin resistance, obesity and impaired insulin synthesis. Recent genome wide association studies (GWAS) shows the intimacy of CDK5 regulatory subunit Associated protein 1-Like 1 (Cdkal1) with the pathophysiology of the diabetes mellitus and its complications, although the exact molecular relation is still unknown. In this short review, we have summarized all the diverse biological roles of Cdkal1 in relation to the onset of diabetes mellitus. Variations in the Cdkal1 transcript are responsible for the accumulation of misfolded insulin and thus generating oxidative and ER stress in the pancreatic β-cells, leading to their destruction. Recent studies have shown that Cdkal1 has an intrinsic thiomethyl transferase activity, which is essential for proper posttranslational processing of pre-proinsulin to produce mature insulin. Moreover, Cdkal1 has also been claimed as an endogenous inhibitor of cdk5, which prevents the cdk5-induced interruption in insulin synthesis through PDX1 translocation from nucleus to cytosol. Recent clinical studies have identified the risk single nucleotide polymorphisms (SNPs) of Cdkal1 as one of the root causes for the onset of diabetic complications. To the best of our knowledge, it is the first comprehensive review which elaborates most of the potential Cdkal1-dependent molecular mechanisms studied yet. In this review, we present a compiled and concise summary about all the diverse roles of Cdkal1 in the context of type 2 diabetes mellitus and its associated complications. This review will be helpful to target Cdkal1 as a potential option for the management of type 2 diabetes mellitus in future.

Graphical abstract

Triglyceride to high density lipoprotein cholesterol ratio is elevated in patients with complicated type 2 diabetes mellitus

Introduction/Aims: Microvascular and macrovascular complications lead to recurrent hospital admissions, hospitalizations, disability, and death in the course of type 2 diabetes mellitus (T2DM). Triglyceride to HDL cholesterol ratio (THR) is associated with insulin resistance. We aimed to find out whether there is a relationship between THR and diabetic complications in patients with T2DM. Methods: Patients with T2DM were enrolled in the study. The study population was divided into two groups according to the presence or absence of diabetic complications. Characteristics and laboratory data of the patients with (group A) and without (group B) diabetic complications were compared. Results: Median THR values of the groups A and B were 3.86 (0.33-53.38) and 2.86 (0.63-17.88), respectively (p = 0.006). THR level was significantly and positively correlated with glycated hemoglobin (HbA1c) (r = 0.12, p = 0.04) and fasting glucose levels (r = 0.14, p = 0.02). Conclusion: We suggest that THR should be monitored in patients with type 2 diabetes mellitus in order to detect diabetic microvascular complications earlier. Increased THR levels should prompt further investigation of diabetic complications in this population.