Elastase-2 (ELA-2) enzyme generates angiotensin-II (AngII) in arteries and is implicated in abnormal vascular remodeling in animal models.Our group demonstrated previously that ELA-2 knockout (ELA-2KO) mice were less susceptible to develop an aorta dilation in a response to AngII infusion. In this study, we hypothesize that susceptibility to an aorta dilation and abdominal aortic aneurysm (AAA) is mediated by AngII receptors (AT1 and AT2). Methods: Male wild type (C57bl/6, WT) and ELA-2KO (CELA-2aTm1Bdr) mice were treated with either saline or AngII (2.28g/g/min) for twenty-eight days by subcutaneously mini-pumps infusion. Mice were divided into four groups: WT treated with saline (WT+SAL, n=5), ELA-2KO treated with saline (ELA-2KO+SAL, n=5), WT treated with AngII (WT+AngII,n=5), and ELA-2KO treated with AngII (ELA-2KO+AngII, n=5). Protein expression of AT1 and AT2 receptor, CD68, and α-actin was measured by immunofluorescence in formalin-fixed, paraffin-embedded aorta tissue. ANOVA and Kruskal Wallis tests were used to compare the average fluorescent intensity between groups. Results: AngII treatment was associated with increased AT1 receptor expression in a WT group, but not with AT2 receptor expression (vs. WT+SAL,p=0.06 and p=0.31, respectively). The ELA-2KO group showed no difference in AT1 receptor expression in a response to AngII infusion compared to a ELA-2KO+SAL group (p=0.81). While ELA-2KO+Ang II mice had lower AT2 expression compared to ELA-2KO+SAL (p=0.05). The α-actin expression was similar in all groups. WT+AngII group expressed more CD68 expression in a response to an AngII treatment that was increased in a WT group (p=0.03), but not in a ELA-2KO group. Conclusion: Our data demonstrate that Ang II treatment did not increase an expression of AT1 receptor in ELA-2KO, but was associated with a downregulation of AT2 receptors. Taken together, this suggests That ELA-2KO mice resistance to developing an aorta dilation/AAA is related to downregulation of Ang II receptors. Our results also highlight the importance of the local/tissue response in the pathophysiology of AAA.
CARDIOVASCULAR RISK PROFILE IN YOUNG PATIENTS WITH EPILEPSY
Abstract Objective: The risk of premature deaths in patients with epilepsy (approx. 50 mln. patients worldwide) is about 2–3 times higher as compared to general population. This phenomenon is mainly explained by cardiovascular causes as well as sudden unexpected deaths in epilepsy (SUDEP). Epilepsy is associated with sympathetic overdrive and renin-angiotensin-system abnormalities all of which may be implicated in organ damage (both directly and indirectly via high blood pressure; BP). In our study, we aimed at the evaluation of several cardiovascular risk factors and organ damage in patients with epilepsy; its’ relation to disease control and comorbid hypertension. Design and method: A total of 48 patients and matched controls were included in the study. Anthropometry, biochemical assessment, office and ambulatory blood pressure, structural and/ or functional vascular changes were recorded. One-way ANOVA and ANCOVA were employed (mean ± SE). Results: Patients were comparable in terms of age and BMI. Hypertensives were aware of high BP in 50% of cases. Study subgroups were comparable in terms of heart rate, serum uric acid, triglicerides, HDL, glucose, serum creatinine and eGFR, serum potassium (P = NS for all comparisons). Total cholesterol was the lowest in well-controlled epileptic patients which was followed by refractory disease and epilepsy with comorbid hypertension (167.6 ± 6.7 vs. 196.9 ± 7.4 vs. 223.5 ± 8.9; respectively). Patients with refractory epilepsy had comparable serum LDL and PWV to hypertensive well-controlled epileptics; both contrasted with values recorded in patients with well-controlled epilepsy who were free of hypertension (LDL: 121.7 ± 6.8 vs. 140.9 ± 8.2 vs. 99.2 ± 6.1; respectively, and PWV: 6.4 ± 0.24 vs. 6.8 ± 0.30 vs. 5.5 ± 0.22; respectively). Reported differences were valid after adjustment for age and BMI. Conclusions: Except for BP values, patients with refractory epilepsy who are free of hypertension have similar CV risk profile to patients with high BP. These findings along with underdiagnosed hypertension may explain higher CV mortality and morbidity documented in epilepsy.
Telomere Length and Risk of Major Adverse Cardiac Events and Cancer in Obstructive Sleep Apnea Patients
Telomere length (TL) is associated with cardiovascular disease (CVD) and cancer. Obstructive sleep apnea (OSA) is also linked to higher risk of CVD and cancer, and to TL. We investigated the association between TL and risk of major adverse cardiac events (MACE) and cancer in OSA patients. We studied 210 individuals undergoing sleep-related studies between 2000 and 2007. Baseline characteristics and follow-up data (available in 164 subjects) were obtained from clinic records. Incidence rates were calculated for the entire group and by OSA status. Hazard ratios were calculated to estimate effects of OSA and TL on risk of MACE and cancer. In total, 32 individuals (20%) developed MACE and/or cancer during 12.7-year follow-up. The OSA group had a higher likelihood of cancer (16.0 vs. 4.9 events per 1000 person-years, P = 0.044) but no clear evidence of an elevated incidence of MACE (10.8 vs. 4.8 events per 1000 person-years, P = 0.293) compared to the non-OSA group. There was no association between TL and MACE- (HR = 1.01, 95% CI 0.78–1.28), or cancer-risk (HR = 1.18, 95% CI 0.96–1.43). Our study warrants further investigation of any modulating effect of OSA on TL and the risk of MACE and cancer.
Moderate-to-severe obstructive sleep apnea is associated with telomere lengthening
Obstructive sleep apnea (OSA) is associated with cardiometabolic diseases. Telomere shortening is linked to hypertension, diabetes mellitus, and cardiovascular diseases. Because these conditions are highly prevalent in OSA, we hypothesized that telomere length (TL) would be reduced in OSA patients. We identified 106 OSA and 104 non-OSA subjects who underwent polysomnography evaluation. Quantitative PCR was used to measure telomere length in genomic DNA isolated from peripheral blood samples. The association between OSA and TL was determined using unadjusted and adjusted linear models. There was no difference in TL between the OSA and non-OSA (control) group. However, we observed a J-shaped relationship between TL and OSA severity: the longest TL in moderate-to-severe OSA [4,918 ± 230 (SD) bp] and the shortest TL in mild OSA (4,735 ± 145 bp). Mean TL in moderate-to-severe OSA was significantly longer than in the control group after adjustment for age, sex, body mass index, hypertension, dyslipidemia, and depression (β = 96.0, 95% confidence interval: 15.4–176.6, P = 0.020). In conclusion, moderate-to-severe OSA is associated with telomere lengthening. Our findings support the idea that changes in TL are not unidirectional processes, such that telomere shortening occurs with age and disease but may be prolonged in moderate-to-severe OSA. NEW & NOTEWORTHY Here, we show that moderate-to-severe obstructive sleep apnea is associated with longer telomeres, independent of age and cardiovascular risk factors, challenging the hypothesis that telomere shortening is a unidirectional process related to age/disease. A better understanding of the mechanisms underlying telomere dynamics may identify targets for therapeutic intervention in cardiovascular aging/other chronic diseases.