Genetic Variations and Subclinical Markers of Carotid Atherosclerosis in Patients with Type 2 Diabetes Mellitus

MX1 and UBE2L6 are potential metaflammation gene targets in both diabetes and atherosclerosis

Background

The coexistence of diabetes mellitus (DM) and atherosclerosis (AS) is widespread, although the explicit metabolism and metabolism-associated molecular patterns (MAMPs) responsible for the correlation are still unclear.

Methods

Twenty-four genetically wild-type male Ba-Ma mini pigs were randomly divided into five groups distinguished by different combinations of 90 mg/kg streptozotocin (STZ) intravenous injection and high-cholesterol/lipid (HC) or high-lipid (HL) diet feeding for 9 months in total. Pigs in the STZ+HC and STZ+HL groups were injected with STZ first and then fed the HC or HL diet for 9 months. In contrast, pigs in the HC+STZ and HL+STZ groups were fed the HC or HL diet for 9 months and injected with STZ at 3 months. The controls were only fed a regular diet for 9 months. The blood glucose and abdominal aortic plaque observed through oil red O staining were used as evaluation indicators for successful modelling of DM and AS. A microarray gene expression analysis of all subjects was performed.

Results

Atherosclerotic lesions were observed only in the HC+STZ and STZ+HC groups. A total of 103 differentially expressed genes (DEGs) were identified as common between them. The most significantly enriched pathways of 103 common DEGs were influenza A, hepatitis C, and measles. The global and internal protein-protein interaction (PPI) networks of the 103 common DEGs consisted of 648 and 14 nodes, respectively. The top 10 hub proteins, namely, ISG15, IRG6, IRF7, IFIT3, MX1, UBE2L6, DDX58, IFIT2, USP18, and IFI44L, drive aspects of DM and AS. MX1 and UBE2L6 were the intersection of internal and global PPI networks. The expression of MX1 and UBE2L6 was 507.22 ± 342.56 and 96.99 ± 49.92 in the HC+STZ group, respectively, which was significantly higher than others and may be linked to the severity of hyperglycaemia-related atherosclerosis. Further PPI network analysis of calcium/micronutrients, including MX1 and UBE2L6, consisted of 58 and 18 nodes, respectively. The most significantly enriched KEGG pathways were glutathione metabolism, pyrimidine metabolism, purine metabolism, and metabolic pathways.

Conclusions

The global and internal PPI network of the 103 common DEGs consisted of 648 and 14 nodes, respectively. The intersection of the nodes of internal and global PPI networks was MX1 and UBE2L6, suggesting their key role in the comorbidity mechanism of DM and AS. This inference was partly verified by the overexpression of MX1 and UBE2L6 in the HC+STZ group but not others. Further calcium- and micronutrient-related enriched KEGG pathway analysis supported that MX1 and UBE2L6 may affect the inflammatory response through micronutrient metabolic pathways, conceptually named metaflammation. Collectively, MX1 and UBE2L6 may be potential common biomarkers for DM and AS that may reveal metaflammatory aspects of the pathological process, although proper validation is still needed to determine their contribution to the detailed mechanism.

The roles and mechanisms of miR-26 derived from exosomes of adipose-derived stem cells in the formation of carotid atherosclerotic plaque

Background

This study explored the serum concentrations of miR-26 in patients with carotid atherosclerosis (CAS) and defined the roles and mechanisms of miR-26 derived from the exosomes of adipose-derived stem cells (ADSC-exos).

Methods

The carotid artery width was diagnosed by ultrasound examination in patients with different degrees of CAS. The serum levels of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) in patients were detected by biochemistry. The serum levels of miR-26 were determined by quantitative polymerase chain reaction (qPCR). A model of CAS in ApoE-/- mice fed with a rich-fat diet was established to analyze the regulatory effects of serum miR-26 on blood lipids in mice. Adipose mesenchymal stem cell lines transfected with miR-26 were established. The regulatory relationship between the expression levels of inflammatory factors, including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and IL-1β, and the expression levels of miR-26 in the supernatant of each group of cells was determined by qPCR. The ADSC-exos were extracted from ADSCs and injected into model mice through the tail vein. The therapeutic effect of ADSCs expressing miR-26 on model mice was evaluated by detecting the levels of inflammatory factors and blood lipids in the serum of the mice.

Results

The degree of atherosclerosis (AS) was positively associated with the intima-media thickness (IMT) of the carotid artery. The serum levels of miR-26 in patients were inversely correlated with the levels of blood lipids (TC, TG, and LDL-C), and positively correlated with HDL-C levels. Similarly, in the CAS mouse model, the serum levels of miR-26 were inversely correlated with the levels of blood lipids (TC, TG, and LDL-C), and positively correlated with HDL-C level. In ADSCs transfected with miR-26, the miR-26 expression in the cell supernatant was negatively regulated by the expression of inflammatory factors, TNF-α, IL-6, and IL-1β, in the cell supernatant. ADSC-exos expressing miR-26 has positive effects on correcting blood lipids and inflammatory factors in the mouse model of CAS.

Conclusions

miR-26 has an active role in CAS and may be a novel target for the treatment of CAS in the future.

Apolipoprotein E in Cardiometabolic and Neurological Health and Diseases

A preponderance of evidence obtained from genetically modified mice and human population studies reveals the association of apolipoprotein E (apoE) deficiency and polymorphisms with pathogenesis of numerous chronic diseases, including atherosclerosis, obesity/diabetes, and Alzheimer’s disease. The human APOE gene is polymorphic with three major alleles, ε2, ε3 and ε4, encoding apoE2, apoE3, and apoE4, respectively. The APOE gene is expressed in many cell types, including hepatocytes, adipocytes, immune cells of the myeloid lineage, vascular smooth muscle cells, and in the brain. ApoE is present in subclasses of plasma lipoproteins, and it mediates the clearance of atherogenic lipoproteins from plasma circulation via its interaction with LDL receptor family proteins and heparan sulfate proteoglycans. Extracellular apoE also interacts with cell surface receptors and confers signaling events for cell regulation, while apoE expressed endogenously in various cell types regulates cell functions via autocrine and paracrine mechanisms. This review article focuses on lipoprotein transport-dependent and -independent mechanisms by which apoE deficiency or polymorphisms contribute to cardiovascular disease, metabolic disease, and neurological disorders.

Distinct pro-inflammatory properties of myeloid cell-derived apolipoprotein E2 and E4 in atherosclerosis promotion

Polymorphisms in the apolipoprotein E (apoE) gene are risk factors for chronic inflammatory diseases including atherosclerosis. The gene product apoE is synthesized in many cell types and has both lipid transport–dependent and lipid transport–independent functions. Previous studies have shown that apoE expression in myeloid cells protects against atherogenesis in hypercholesterolemic ApoE^−/− mice. However, the mechanism of this protection is still unclear. Using human APOE gene replacement mice as models, this study showed that apoE2 and apoE4 expressed endogenously in myeloid cells enhanced the inflammatory response via mechanisms independent of plasma lipoprotein transport. The data revealed that apoE2-expressing myeloid cells contained higher intracellular cholesterol levels because of impaired efflux, causing increasing inflammasome activation and myelopoiesis. In contrast, intracellular cholesterol levels were not elevated in apoE4-expressing myeloid cells, and its proinflammatory property was found to be independent of inflammasome signaling and related to enhanced oxidative stress. When ApoE^−/− mice were reconstituted with bone marrow from various human APOE gene replacement mice, effective reduction of atherosclerosis was observed with marrow cells obtained from APOE3 but not APOE2 and APOE4 gene replacement mice. Taken together, these results documented that apoE2 and apoE4 expression in myeloid cells promotes inflammation via distinct mechanisms and promotes atherosclerosis in a plasma lipoprotein transport–independent manner.

Ultrasonic assessment of carotid intima-media thickness in migraine: a meta-analysis

Objective

Migraine is believed to be a risk factor for cerebrovascular diseases, and previous studies have indicated an association between migraine and cerebral atherosclerosis. Carotid artery intima-media thickness (IMT) is considered to be a biomarker of atherosclerosis pathology. This study aimed to investigate the relationship between carotid IMT and migraine by conducting a meta-analysis.

Methods

We searched Web of Science, PubMed, and the Cochrane Library for eligible studies assessing carotid IMT in patients with migraine and controls. Data were extracted independently by two reviewers and analyzed using Review Manager 5.3 software.

Results

The meta-analysis included seven articles with 555 subjects (279 migraine patients, 276 controls). Carotid IMT was significantly greater in patients with migraine compared with controls. However, there were no significant differences in IMT between patients with migraine with aura (MA) and controls, migraine without aura (MO) and controls, and patients with MA and MO.

Conclusion

Patients with migraine have greater carotid IMT than individuals without migraine, suggesting an association between atherosclerosis and migraine. However, further studies with more samples are needed to confirm this finding.

Role of Dietary Gluten in Development of Celiac Disease and Type I Diabetes: Management Beyond Gluten-Free Diet

Gluten triggers Celiac Disease (CD) and type I diabetes in genetically predisposed population of human leukocyte antigen DQ2/DQ8+ and associates with disorders such as schizophrenia and autism. Application of a strict gluten-free diet is the only well-established treatment for patients with CD, whereas the treatment for patients with celiac type I diabetes may be depend on the timing and frequency of the diet. The application of a gluten-free diet in patients with CD may contribute to the development of metabolic syndrome and nonalcoholic fatty liver disease and may also lead to a high glycemic index, low fiber diet and micronutrient deficiencies. The alteration of copper bioavailability (deficient, excess or aberrant coordination) may contribute to the onset and progress of related pathologies. Therefore, nutrient intake of patients on a gluten-free diet should be the focus of future researches. Other gluten-based therapies have been rising with interest such as enzymatic pretreatment of gluten, oral enzyme supplements to digest dietary gluten, gluten removal by breeding wheat varieties with reduced or deleted gluten toxicity, the development of polymeric binders to suppress gluten induced pathology.

Subclinical Atherosclerosis in Patients With Type 1 Diabetes Mellitus: A Systematic Review and Meta-Analysis

Cardiovascular (CV) risk in type 1 diabetes mellitus (T1DM) is increased. In this study, we evaluated the differences in major markers of CV risk between patients with T1DM and healthy controls by a systematic review and meta-analysis. Literature from PubMed, EMBASE, and The Cochrane Library comparing CV risk markers between patients with T1DM and controls was obtained. The overall standard mean differences (SMDs) of carotid intima–media thickness (cIMT), endothelium-dependent flow-mediated dilation (FMD%), carotid-femoral pulse wave velocity (cf-PWV), and glyceryl trinitrate-mediated dilatation (GTN%) with its 95% confidence interval (CI) between patients with T1DM and control groups were calculated using fixed-effect or random-effect model. Heterogeneity was evaluated using the Cochran Q and I2 statistics. The results showed that patients with T1DM had a significantly greater cIMT (SMD: 0.89; 95% CI, 0.69-1.09; P < .001), significantly lower FMD% (SMD: −1.45%; 95% CI, −1.74 to −1.17; P < .001), significantly increased cf-PWV (SMD: 0.57; 95% CI, 0.03-1.11; P < .001), and significantly decreased GTN% (SMD: −1.11; 95% CI, −1.55 to −0.66; P < .001) than controls. Our results support the current evidence for an elevated CV burden in patients with T1DM and affirm the clinical utility of markers of subclinical atherosclerosis in the management of these patients.