Subclinical Vascular Endothelial Dysfunctions and Myocardial Changes With Type 1 Diabetes Mellitus in Children and Adolescents

Vascular endothelial dysfunction, accelerated thickening of arterial intima, and changes in ventricular functions contribute to increased cardiovascular morbidity in type 1 diabetes mellitus (T1DM). This study aimed to investigate the functional-structural changes in the arteries and myocardium together with affection of highly sensitive C-reactive protein (hsCRP), circulating endothelial cells (CECs), and vitamin C levels in children with T1DM. Also, to test the association with early atherosclerotic changes. The study included 30 children with a diagnosis of T1DM and 30 healthy subjects matched by sex, age, and body mass index. Serum lipids, HbA1c, hsCRP, vitamin C, and CECs were detected. Corrected QT interval (QTc), cardiac dimensions, and left ventricular (LV) functions were assessed using conventional echocardiography. Noninvasive ultrasound was used to measure brachial artery flow-mediated dilation (FMD) responses and carotid intima-media thickness (IMT). The QTc interval was significantly higher in the diabetic patients than in the control subjects (P < 0.001). The findings showed LV diastolic dysfunction as reflected by significantly lower early peak flow velocity, decreased E/A ratio, increased early filling deceleration time (DcT), and prolonged isovolumic relaxation time (IVRT) (P < 0.001 for each). The children with diabetes had a significantly lower FMD response, increased IMT, lower vitamin C level, higher hsCRP, and higher CEC compared with the control subjects (P < 0.001 for each). A positive correlation between CEC and HbA1c was found (P = 0.004). An alteration in myocardial function and endothelial dysfunction may begin early with the association of early atherosclerotic changes. These changes are accelerated when glycemic control is poor. The authors recommend early and close observation of children with diabetes for any alterations in cardiac and vascular endothelial function. Vitamin C supplementation may reduce the risk of complications.     

Thioredoxin-interacting protein is required for endothelial NLRP3 inflammasome activation and cell death in a rat model of high-fat diet

Aims/hypothesis

Obesity and hypertension, known pro-inflammatory states, are identified determinants for increased retinal microvascular abnormalities. However, the molecular link between inflammation and microvascular degeneration remains elusive. Thioredoxin-interacting protein (TXNIP) is recognised as an activator of the NOD-like receptor pyrin domain containing-3 (NLRP3) inflammasome. This study aims to examine TXNIP expression and elucidate its role in endothelial inflammasome activation and retinal lesions.

Methods

Spontaneously hypertensive (SHR) and control Wistar (W) rats were compared with groups fed a high-fat diet (HFD) (W+F and SHR+F) for 8–10 weeks.

Results

Compared with W controls, HFD alone or in combination with hypertension significantly induced formation of acellular capillaries, a hallmark of retinal ischaemic lesions. These effects were accompanied by significant increases in lipid peroxidation, nitrotyrosine and expression of TXNIP, nuclear factor κB, TNF-α and IL-1β. HFD significantly increased interaction of TXNIP–NLRP3 and expression of cleaved caspase-1 and cleaved IL-1β. Immunolocalisation studies identified TXNIP expression within astrocytes and Müller cells surrounding retinal endothelial cells. To model HFD in vitro, human retinal endothelial (HRE) cells were stimulated with 400 μmol/l palmitate coupled to BSA (Pal-BSA). Pal-BSA triggered expression of TXNIP and its interaction with NLRP3, resulting in activation of caspase-1 and IL-1β in HRE cells. Silencing Txnip expression in HRE cells abolished Pal-BSA-mediated cleaved IL-1β release into medium and cell death, evident by decreases in cleaved caspase-3 expression and the proportion of live to dead cells.

Conclusions/interpretation

These findings provide the first evidence for enhanced TXNIP expression in hypertension and HFD-induced retinal oxidative/inflammatory response and suggest that TXNIP is required for HFD-mediated activation of the NLRP3 inflammasome and the release of IL-1β in endothelial cells.     

Differential expression of cell cycle regulators in HCV-infection and related hepatocellular carcinoma

AIM: To investigate cell cycle proteins in chronic hepatitis C virus infection in order to analyze their role in the process of hepatocyte transformation and to characterize their prognostic properties.METHODS: Subjects of the current study included 50 cases of chronic hepatitis C (CHC) without cirrhosis, 30 cases of CHC with liver cirrhosis (LC), and 30 cases of hepatitis C-related hepatocellular carcinoma (HCC) admitted to the Department of Hepato-Gastroenterology, Theodor Bilharz Research Institute (TBRI), Giza, Egypt. Fifteen wedge liver biopsies, taken during laparoscopic cholecystectomy, were also included as normal controls. Laboratory investigations including urine and stool analysis, liver function tests and prothrombin concentration; serologic markers for viral hepatitis and ultrasonography were done for all cases of the study together with immunohistochemical analysis using primary antibodies against Cyclin D1, Cyclin E, p21, p27 and Rb/p105 proteins.RESULTS: Normal wedge liver biopsies didn’t express Cyclin E or Rb/p105 immunostaining but show positive staining for Cyclin D1, p21 and p27. Cyclin D1 expressed nuclear staining that was sequentially increased from CHC to LC (P < 0.01) to HCC (P < 0.001) cases; meanwhile, Cyclin E revealed nuclear positivity only in the case of HCCs patients that was directly correlated to Rb/p105 immuno-reactivity. The expression of p21 and p27 was significantly increased in CHC and LC cases compared to normal controls and HCCs with no significant difference between well- and poorly-differentiated tumors. p21 showed only a nuclear pattern of staining, while, p27 presented with either cytoplasmic and/or nuclear reactivity in all studied cases. Correlation analysis revealed a direct relation between Cyclin D1 and p21 in CHC cases (P < 0.001), between Cyclin D1 and Cyclin E in HCCs (P < 0.01); however, an inverse relationship was detected between Cyclin D1 and p21 or p27 (P < 0.001) and between p21 and Rb/p105 (P < 0.05) in HCCs.CONCLUSION: Upregulation of Cyclin D1 in CHC plays a vital role in the development and differentiation of HCC; while, Cyclin E may be a useful marker formonitoring tumor behavior. p21 and p27 can be used as predictive markers for HCC. Furthermore, higher expression of Rb/p105 as well as inverse relation with p21 and histologic grades suggests its important role in hepatic carcinogenesis.     

Flow cytometric assessment of circulating platelet and erythrocytes microparticles in young thalassemia major patients: relation to pulmonary hypertension and aortic wall stiffness

Heart disease is the leading cause of mortality and morbidity in β‐thalassemia major (β‐TM). Aggregability of abnormal red cells and membrane‐derived microparticles (MPs) stemming from activated platelets and erythrocytes are responsible for thrombotic risk. We measured platelet and erythrocyte MPs (PMPs and ErMPs) in 60 young β‐TM patients compared with 40 age‐ and sex‐matched healthy controls and assessed their relation to clinicopathological characteristics and aortic elastic properties. Patients were studied stressing on transfusion history, splenectomy, thrombotic events, chelation therapy, hematological and coagulation profiles, flow cytometric measurement of PMPs (CD41b⁺) and ErMPs (glycophorin A⁺) as well as echocardiographic assessment of aortic elastic properties. Aortic stiffness index and pulmonary artery pressure were significantly higher, whereas aortic strain and distensibility were lower in TM patients than controls (P < 0.001). Both PMPs and ErMPs were significantly elevated in TM patients compared with controls, particularly patients with risk of pulmonary hypertension, history of thrombosis, splenectomy or serum ferritin >2500 μg/L (P < 0.001). Compliant patients on chelation therapy had lower MPs levels than non‐compliant patients (P < 0.001). PMPs and ErMPs were positively correlated to markers of hemolysis, serum ferritin, D‐dimer, vWF Ag, and aortic stiffness, whereas negatively correlated to hemoglobin level and aortic distensibility (P < 0.05). We suggest that increased MPs may be implicated in vascular dysfunction, pulmonary hypertension risk, and aortic wall stiffness observed in thalassemia patients. Their quantification could provide utility for early detection of cardiovascular abnormalities and monitoring the biological efficacy of chelation therapy.     

Evaluation of the diagnostic value of serum and tissue apoptotic cytokeratin-18 in patients with chronic hepatitis C

Background and study aimsHepatitis C virus (HCV) is considered the most common aetiology of chronic liver disease (CLD) in Egypt. The disease severity ranges from mild illness to cirrhosis and hepatocellular carcinoma. A role for apoptosis in liver damage caused by HCV chronic infection has been suggested. Cytokeratin 18 (CK-18) is the major intermediate filament protein in the liver and is a known caspase substrate in hepatocyte apoptosis. Therefore, we analysed the serum and tissue levels of CK-18 in patients with chronic HCV infection to evaluate its role in hepatocyte apoptosis. We also correlated CK-18 expression with the severity of hepatic pathology.Patients and methodsThis study examined 80 Egyptian patients with liver disease. There were 69 patients with chronic hepatitis C and 11 patients with hepatitis C-induced cirrhotic changes. Fifteen healthy controls were also included in the study. The levels of CK-18 fragment were quantified in paired serum and liver biopsy samples.ResultsThe serum and tissue CK-18 levels were reduced in chronic HCV patients compared to early cirrhosis patients. This result indicates that serum levels of CK-18 and the hepatic expression of CK-18 might play an important role in disease progression. The serum and tissue levels of CK-18 were significantly increased and directly correlated with inflammation severity, stage of fibrosis, and ALT levels in the chronic HCV group and the cirrhotic liver group. There was no significant difference in viral load between patient cohorts.ConclusionThe serum level and the hepatic expression of CK-18 are related to disease activity and are directly correlated with METAVIR scoring. This result suggests that serum CK-18 levels may be useful for monitoring disease activity in chronic HCV and liver cirrhosis patients.     

The association between extracoronary calcification and coronary artery disease in patients with type 2 diabetes mellitus

Cardiovascular complications are the major cause of diabetes-associated morbidity and mortality. However, not all patients with diabetes are at increased risk for cardiovascular disease (CVD). Coronary artery calcification was found to be a powerful predictor of coronary artery disease (CAD). The presence of extracoronary cardiac calcification as a useful predictor of CAD is not yet established, especially in type 2 diabetes mellitus (T2DM). The aim of this study was to evaluate the relation between extracoronary calcification and extent of CAD in a group of T2DM patients who were scheduled for computed tomographic coronary angiography (CTCA). We prospectively studied 380 patients (151 had T2DM) under the age of 60 years who were scheduled for CTCA because of suspected CAD. Severity of CAD was assessed by Gensini score. Coronary artery calcium score (CACS) as well as calcium score in the aortic valve, mitral annulus, ascending aorta, and descending aorta were measured by a 256-row multidetector computed tomography scanner with dedicated software for calcium calculation. Patients with known CAD were excluded. Diabetic and nondiabetic patients had comparable age and gender distribution. However, the diabetic group had higher Gensini score, CACS, and extracoronary calcium score (ECCS). Logistic regression analyses identified male gender and ECCS as significant predictors for the presence of CAD in diabetic patients. Age, smoking, and ECCS were the significant predictors of CAD in nondiabetic patients. Type 2 diabetic patients had increased coronary and extracoronary calcification. ECCS was found to be a significant predictor of CAD in diabetic and nondiabetic patients only when CACS was not taken into account.     

In‐stent neoatherosclerosis and tissue characteristics of restenotic lesions following implantation of second generation drug‐eluting stents in unrestricted coronary lesions: Optical frequency domain imaging study

BACKGROUND

Differences in stent platform, polymer coatings, and antirestenotic drugs among the current in use second‐generation drug‐eluting stents (G2‐DESs) may induce significant variations in neointimal response and vascular healing, which may impact the prevalence of neoatherosclerosis (NA) and morphological appearance of the restenotic tissue.

METHODS AND RESULTS

Utilizing Optical frequency domain imaging, two independent reviewers, retrospectively compared the prevalence of neoatherosclerosis (NA), and the morphological differences, and tissue characteristics of 50 G2‐DESs in‐stent restenosis (ISR) lesions (35 everolimus‐eluting stent [22 cobalt‐chromium (CoCr), 13 platinum‐chromium (PtCr)], and 15 biolimus‐eluting stent [BES]) implanted liberally in unrestricted coronary lesions. More than half of the stents were implanted in type C lesions, while 40% of the stents were implanted primarily in lesions with recanalized chronic total occlusion. NA, defined as a neointima formation with the presence of lipids or calcification, was observed in fewer than half (24/50) of all ISR lesions with no significant in‐between group differences (41%, 69%, and 40% in CoCr, PtCr, and BES respectively, P = 0.22), nor were there any significant differences in the morphological appearance or tissue characteristics between all G2‐DESs subtypes.

CONCLUSIONS

Acknowledging some limitations, our results may suggest that the prevalence of NA and the morphological appearance of restenotic lesions might not differ when G2‐DESs are implanted in unrestricted, rather complex, coronary lesions.

     

Evaluation of loss of heterozygosity of chromosome 22q11.21 region in patients with congenital heart diseases

The 22q11.21 region is prone to low-copy repeats events that lead to congenital anomaly disorders. We tested genomic DNA of 20 families with non-syndromic CHD patients using a set of three known consecutive high polymorphic short tandem repeat (STR) markers along the 22q11.21 region; D22S941, D22S944 and D22S264 loci. We found loss of heterozygosity (LOH) in D22S941 locus in 2 out of 20 families (10%) with 2 offspring affected by ASD combined with PS and TOF respectively. No LOH found in D22S944 and D22S264 loci either in affected cases or control group and no LOH found in D22S941 in the control group. Also we observed that D22S944 locus prone to be less allele diversity than D22S941 and D22S264 loci.     

Prognostic value of serum level of interleukin-6 and interleukin-8 in metastatic breast cancer patients

Previous studies indicated that interleukins may stimulate cancer cells growth and contribute to loco regional relapse as well as metastasis. The aim in this study was to investigate the level of interleukin-6 (IL-6) and interleukin-8 (IL-8) in metastatic breast cancer patients and find out the relation between the levels of these cytokines and the clinical out come of patients and to predict the value of these cytokines as independent prognostic factors. The present study was carried out on 40 women divided into two groups; the first group included 30 patients diagnosed as having metastatic breast cancer. The second group included 10 healthy women as controls. An immunoenzymometric assays for the quantitative measurement of human IL-6 and IL-8 were used. The serum level of IL-6 and IL-8 were measured for patients and controls. Serum level of both IL-6 and IL-8 were found to be higher in patients than in healthy volunteers. Serum IL-6 was detected in all patients and controls with a mean value of (25.3 pg/ml) versus (1.5 pg/ml) for patients and controls respectively and this difference was statistically highly significant (P < 0.001). Serum IL-8 was detected in 26 patients (86.7%) and 7 controls (70%) with a mean value of (8.96 pg/ml) versus (3.9 pg/ml) for patients and controls respectively and this difference was also statistically highly significant (P < 0.001). Tumors with size larger than 5 cm at diagnosis were associated with higher level of both IL-6 (32.8 pg/ml) and IL-8 (10.2 pg/ml) in comparison with those with size less than 5cm (IL-6 14 pg/ml) and (IL-8 7.2 pg/ml) and the difference in both cases was statistically significant (P < 0.05). Patients with more than 3 positive lymph nodes had higher level of both IL-6 and IL-8 with a mean value of 32.8 pg/ml and 10.2 pg/ml for IL-6 and IL-8 respectively, than those with less than 3 positive lymph nodes with mean value of 14 pg/ml and 6.9 pg/ml for IL-6 and IL-8 respectively and this difference was statistically significant (P < 0.05). Seventeen of the patients had only one metastatic site (bone or liver or lung metastasis) and 13 had more than one metastatic site and the difference between the two groups was statistically highly significant regarding both IL-6 and IL-8 (P < 0.001). The mean level of IL-6 was 14.6 pg/ml for patients with one metastatic site versus 29.2 pg/ml for patients with more than one metastatic site. The mean level of IL-8 was 6.2 pg/ml versus 11.3 pg/ml for patients with one metastatic site and patients with more than one metastatic site respectively. However, the level of IL-6 and IL-8 did not correlate with hormonal receptors status, tumour grade, menopausal status or site of metastasis. Thus, it could be concluded that serum level of IL-6 and IL-8 are useful prognostic factors in metastatic breast cancer patients.