ABSTRACT
Objective:To explore the role of SUMOylaiton of peroxisome proliferator-activated receptor γ (PPARγ) in diabetes mellitus prompted inflammation and atherosclerosis in vascular and endothelial cells.Methods:From September 2014 to January 2017, 32 Sprague-Dawley rats in 14 weeks-old were divided into sham operated group, artery injured without diabetes group, artery injured with diabetes group and ubiquitin-conjugating enzyme 9 (UBC9) transfection group (Group D) by random digits table method with 8 rats each. Model of type 1 diabetes mellitus (T1DM) and rat carotid artery balloon injury was made in the assigned group. One rat was excluded because of model failure in each group. Systolic and diastolic common carotid artery diameter and intimal thickness of injured and healthy common carotid artery were evaluated by vascular ultrasound, and the standardized common carotid artery diastolic diameter (sCADD) was calculated. Histological tests and immunohistochemical staining were performed to evaluate intimal hyperplasia, and the ratio of intimal area to media area was calculated when the media area was equal. Human umbilical vein endothelial cells (HUVEC) were cultured 24 h in high glucose medium with different duration and concentration, and the expression levels of interleukin (IL)-8 and IL-1β mRNA were determined by real time reverse transcription polymerase chain reaction (RT-PCR), the expression level of UBC9 was determined by Western blot method, SUMOylation assay kit was used to evaluate SUMOylation of PPARγ. HUVEC was cultured in vitro and PPAR was stimulated by high glucose at different concentrations and different times PPARγ SUMOylation level. UBC9 was overexpressed by lentivirus in vivo and in vitro, and the PPARγ SUMOylation level was detected.Results:The intimal thickness, intimal area and ratio of intimal area to media area 8 weeks after carotid artery injuring in sham operated group, artery injured without diabetes group and artery injured with diabetes group were increased respectively: (0.026 ± 0.018), (0.084 ± 0.007) and (0.264 ± 0.022) mm; (0.18 ± 0.09) × 10 6, (0.32 ± 0.06) × 10 6 and (1.64 ± 0.22)×10 6 μm 2; 0.345 ± 0.073, 0.570 ± 0.080 and 2.710 ± 0.220, the sCADD was decreased respectively: 0.903 ± 0.084, 0.800 ± 0.071 and 0.330 ± 0.036, and there were statistical differences ( F = 10.40, 9.40, 8.20 and 8.60; P<0.05). After HUVEC was cultured in high glucose for 24 h, the IL-8 mRNA at sugar concentrations of 10, 20 and 40 mmol/L was 1.00 ± 0.11, 3.57 ± 0.22 and 4.07 ± 0.40, the IL-1β mRNA was 1.00 ± 0.07, 3.32 ± 0.29 and 5.13 ± 0.19, and there were statistical differences ( F = 73.05 and 205.80, P<0.05). The level of PPARγ SUMOylation and UBC9 in artery injured with diabetes group were significantly lower than those in artery injured without diabetes group (0.46 ± 0.25 vs. 1.00 ± 0.21 and 0.45 ± 0.02 vs. 1.00 ± 0.07), and there were statistical differences ( P<0.05); there was no statistical difference in PPARγ between 2 groups (0.94 ± 0.07 vs. 1.00 ± 0.04, P>0.05). The UBC9 and PPARγ SUMOylation at sugar concentrations of 0, 10, 20 and 40 mmol/L were decreased respectively (0.99 ± 0.05, 0.80 ± 0.06 and 0.62 ± 0.05; 1.00 ± 0.05, 0.57 ± 0.13 and 0.55 ± 0.08), and there were statistical differences ( F = 21.02 and 14.31, P<0.05); there was no statistical difference in PPARγ (1.00 ± 0.03, 0.90 ± 0.04 and 0.91 ± 0.05; F = 3.11, P>0.05). In HUVEC cultured in high glucose medium (20 mmol/L) for 6, 12, 24 and 48 h, the UBC9 and PPARγ SUMOylation were downregulated progressively (1.00 ± 0.09, 0.75 ± 0.05, 0.70 ± 0.08, 0.38 ± 0.04 and 0.35 ± 0.03; 1.00 ± 0.03, 0.86 ± 0.01, 0.59 ± 0.01, 0.51 ± 0.11 and 0.35 ± 0.08), and there were statistical differences ( F = 36.06 and 33.13, P<0.05); but there was no statistical difference in PPARγ (1.00 ± 0.03, 1.14 ± 0.02, 1.18 ± 0.17, 0.98 ± 0.01 and 1.04 ± 0.05; F = 1.90, P>0.05). After overexpression of UBC9 in rats with diabetes, histological analysis showed that UBC9 in artery injured without diabetes group, artery injured with diabetes group and UBC9 transfection group was 1.53 ± 0.18, 1.00 ± 0.22 and 3.62 ± 0.35, there was statistical difference ( F = 5.64, P<0.05). Ultrasonic test results show that in artery injured without diabetes group, artery injured with diabetes group and UBC9 transfection group intimal thickness was increased respectively: (0.077 ± 0.015), (0.216 ± 0.007) and (0.125 ± 0.014) mm, and there was statistical difference ( F = 27.18, P<0.05). Histological analysis showed that intimal area in artery injured without diabetes group, artery injured with diabetes group and UBC9 transfection group was (0.335 ± 0.066) ×10 6, (1.053 ± 0.103) ×10 6 and (0.544 ± 0.040) ×10 6 μm 2, the ratio of intimal area to media area was 0.63 ± 0.063, 2.03 ± 0.052 and 0.93 ± 0.100, there were statistical differences ( F = 13.58 and 53.96, P<0.05). Conclusions:Diabetes mellitus could inhibit the PPARγ SUMOylaiton and prompt inflammation and atherosclerosis in vascular and endothelial cells. Upregulation of PPARγ SUMOylaiton though UBC9 overexpressioncould play a protecting role in diabetes mellitus prompted atherosclerosis.
ABSTRACT
Objective:To study the effects of conservative treatment versus percutaneous interventional treatment(PCI)on symptoms and prognosis of chronic coronary syndrome patients aged over 75 years with fractional flow reserve(FFR)in the grey zone(0.75≤FFR≤0.80).Methods:A total of 96 coronary heart disease(CHD)patients aged over 75 years undergone FFR examination in our hospital from January 2011 to December 2017 were retrospectively selected.All patients showed stenosis of 50%-90% in at least one main coronary artery and had FFR values within the range of 0.75-0.80(0.75≤FFR≤0.80). According to the treatment, patients were divided into the optimized medication group(OMT group, n=35)and the PCI group(n=61). The degree of angina alleviation assessed by the Seattle Angina Questionnaire(SAQ)and the incidence of major adverse cardiovascular endpoints(death, myocardial infarction, stroke, and repeated revascularization)were recorded during the one-year follow-up after treatment.Results:There was no significant difference in baseline data including age, gender and comorbidities between the OMT and PCI groups( P>0.05). The incidence of previous myocardial infarction, and the basal level of low-density lipoprotein cholesterol(LDL-C)were higher in the PCI group than in the OMT group( P<0.05). One-year follow-up showed that there was no significant difference between the OMT and PCI groups in the score of SAQ(77.6 ± 19.5 vs. 83.1 ± 22.8, P>0.05)and the incidence of composite MACEs(11.4% or 4 / 35 vs. 9.8% or 6/61, P>0.05). However, the incidence of repeated target vessel revascularization was lower in the PCI group than in the OMT group(1.6% or 1 case vs. 5.8% or 2 cases, P<0.05). Conclusions:In elderly CHD patients aged over 75 years with FFR values between 0.75-0.8 in the grey zone, optimal medication treatment has similar effects as the PCI on symptom alleviation, and no significant increase in composite MACEs is found at one-year follow-up.