Abstract 444: A Six-Microrna Panel Identified as a Potential Biomarker for Early-Stage Atherosclerotic Lesions

Introduction: Atherosclerosis is a progressive disease, and it’s the common cause of cardiovascular disease (CVD). CVD is the leading cause of morbidity and mortality in the US. It is important to detect early-stage asymptomatic atherosclerosis prior to progression to plaques. However, it is not feasible to obtain target tissues from humans with early-stage atherosclerosis. We tested the hypothesis that a panel of microRNAs (miRNAs) expressed in atherosclerotic lesions and expressed in plasma of the same baboons are potential biomarkers indicative of initiation and progression of atherosclerosis. Methods and Results: We used small RNA-Seq to identify miRNA expression profiles in atherosclerotic lesions and in plasma of baboons. We challenged adult baboons (n=24) with a high cholesterol, high fat (HCHF) diet for two years. After the diet challenge, common iliac arteries were harvested, fixed in 10% buffered formalin and stained with Sudan IV. We observed interesting fatty streak lesion variations, including early stage (EGES), flat (F) and raised (R) lesions, corresponding, respectively, to AHA lesion types I, II and V. We identified 45 miRNAs differentially expressed in fatty streak lesions (ES vs F=0; ES vs R =36; F vs R=9), and 43 miRNAs in plasma of the same animals (ES vs F=0; ES vs R =21; F vs R=22). Further, we observed that miR-30-5p, miR-340-5p, miR-548-5p and let-7-3p were expressed in flat lesions as well as in plasma, whereas miR-30-5p and miR-21-5p were expressed in raised lesions and in plasma. FDR < 0.05. Conclusions: We conclude that a panel of six miRNAs differentially expressed in fatty streak lesions and differentially expressed in plasma of the same animals is a potential biomarker indicative of initiation and progression of atherosclerosis in baboons. Future studies will focus on translating baboon findings to humans.

Abstract 626: Vascular Endothelial HSP60 and Von Willebrand Factor Induction Are Both Involved in Promoting Fatty-Streak Formation in ApoE Null Mice

Objectives: This study was designed to determine the murine atherosclerosis in ApoE null mice with inducible expression of human heat shock protein 60 (hHSP60) in vascular endothelium. Background: Autoimmunity to HSP60 may be involved in eliciting early atherosclerotic lesions. Most classical risk factors of atherosclerosis were previously shown in cell culture models to induce HSP60 expression in vascular ECs and in vivo particularly at regions predilected to lesions. However, it has not been demonstrated directly in an animal model whether HSP60 induction in ECs are capable of influencing lesion formation. Methods: We developed ApoE -/- ::Cdh5-CreER T2 ::G-Lox-HSP60 triple Tg mouse model with tamoxifen-induced hHSP60 expression in ECs. Eight week-old triple TG mice were fed by tamoxifen citrate-contained chow for 2 weeks, followed by high fat chow (HF) for additional 4 and 8 weeks before sacrificed for oil red staining for fatty streaks and IHC staining. Results: In tamoxifen-fed triple Tg mouse, vascular EC expression of hHSP60 increased fatty-streak formation and increased the severity of lesions in comparison with uninduced triple Tg or wildtype ApoE mouse. In triple Tg mouse, we found tamoxifen strongly induced HSP60 expression in ECs of the lesions and to a lesser degree in ECs of veins and other arterial regions not predilected to lesions. Concomitant VWF induction at ECs and subendothelial regions was observed at areas with increased HSP60 expression. Conclusions: hHSP60 induction at vascular ECs accelerates fatty-steak formation in ApoE null mice that may involve increasing local VWF expression.

PENGARUH PEMBERIAN JUS BUAH PEPAYA (Carica Papaya L) TERHADAP GAMBARAN HISTOPATOLOGIK FATTY STREAK PADA DINDING AORTA ABDOMINALIS TIKUS WISTAR JANTAN HIPERKOLESTEROLEMIK

Papaya (Carica papaya L) is rich of antioxidants, such as betacarotene, which is a powerful antidote to reactive oxygen compound (ROS) and stimulates the body to convert toxic substances into harmless compounds. In atherosclerotic lesions, antioxidants inhibit the oxidation of LDL cholesterol and prevent the oxidative stress, therefore, reducing the vascular endothelial dysfunction. This study aimed to obtain the effect of papaya given orally on histopathological changes which was determined by numbers of foam cells and abdominal aortic wall thickness of male hypercholesterolemic wistar rats. This was an experimental study. Samples were 24 adult male wistar rats divided into five groups. The negative control group K1 was fed on standard diet for 2 weeks and the positive control group K2, each was fed on diet of egg yolks 5 mg/day for 2 weeks. There were three treatment groups: P1, each was fed on papaya juice 2,6 g/day for 2 weeks; P2, each was fed on papaya juice 2,6 g/day for 4 weeks; and P3, each was fed on papaya juice 2,6 g/day for 6 weeks by using nasogastric tube. After the treatment period of each sample group, the wistar rats were decapitated, and then the levels of total cholesterol and LDL of blood serum were examined as well as the histopathological changes were identified. Data were analyzed by using Oneway-Anova test, followed by Post-Hoc test. The results showed that among P1, P2, and P3 groups there were reductions in the numbers of foam cells in the walls of the abdominal aorta and in the thickness of abdominal aortic wall compared to the K2. Conclusion: Papaya juice which was given orally for 2-4 weeks could reduce the histopathological changes of abdominal aortic walls of male hypercholesteremic wistar rats.Keywords: papaya, antioxidant, hypercholesterolemic, histopathological changes, fatty streakAbstrak: Pepaya (Carica papaya L) kaya akan antioksidan beta-karoten yang merupakan penawar kuat untuk senyawa oksigen reaktif (ROS) dan berkemampuan menstimulasi tubuh untuk mengubah substansi toksik menjadi senyawa yang tidak berbahaya. Pada lesi aterosklerotik, antioksidan dapat menghambat oksidasi kolesterol LDL dan stres oksidatif sehingga mengurangi terjadinya disfungsi endotel pembuluh darah. Penelitian ini bertujuan untuk mengetahui efek pemberian jus buah pepaya secara oral terhadap gambaran histopatologik yaitu jumlah sel busa dan ketebalan dinding pembuluh darah dari aorta abdo-minalis tikus wistar jantan yang hiperkolesterolemik. Penelitian ini bersifat eksperimental dengan rancangan Randomized Post-test Only Control Group Design. Sampel 24 ekor tikus wistar jantan dewasa dibagi dalam 5 kelompok. Kelompok kontrol negatif K1 diberi diet pakan standar selama 2 minggu dan kelompok kontrol positif K2 diberi diet kuning telur 5 mg/ekor/hari selama 2 minggu. Terdapat tiga kelompok perlakuan: P1 diberi jus pepaya 2,6 g/ekor/hari selama 2 minggu; P2 diberi jus pepaya 2,6 g/ekor/hari selama 4 minggu; dan P3 yang diberi jus pepaya 2,6 g/ekor/hari selama 6 minggu melalui sonde hidung. Setelah masa perlakuan masing-masing kelompok, sampel didekapitasi, kemudian diukur kadar kolesterol total dan LDL serum darah, serta diidentifikasi gambaran histopatologik yaitu jumlah sel busa dan ketebalan dinding aorta abdominalis. Data dianalisis dengan uji Oneway- Anova dan dilanjutkan dengan uji Post-Hoc. Hasil penelitian menunjukkan bahwa pemberian jus buah pepaya 2,6 gram/ekor pada kelompok perlakuan P1, P2, dan P3 dapat menurunkan jumlah sel busa pada dinding aorta abdominalis dan ketebalan dinding aorta abdominalis tikus wistar jantan yang hiperkolesterolemik dibandingkan dengan kelompok kontrol positif K2. Simpulan: Pemberian jus pepaya per oral selama 2-4 minggu dapat menurunkan perubahan histopatologik dinding aorta abdominalis tikus wistar jantan yang hiperkolesterolemik.Kata kunci: pepaya, antioksidan, hiperkolesterolemik, histopatologik, fatty streak.

GAMBARAN HISTOPATOLOGI AORTA TIKUS WISTAR YANG TERPAPAR ASAP ROKOK

Cigarette smoking is one of the high risk factor of atherosclerosis. Atherosclerosis signed by plaque in artery and can caused constriction in the blood vessels. Atherosclerosis often occured in the blood vessels of the aortic. The purpose of these study is to see the histopatologic image of wistar rats aortic after being exposed by cigarrete smoke. This experimental study conducted throughout 5months using 10 rats wistar devided into 3 groups. Group A as a negative control (2 rats). Group B are exposed by cigarette smoke as much 24 cigarettes for 20 days (4 rats). Group C exposed by cigarette smoke as much 20 cigarette per day for 30 days (4 rats). The rats has been autopsied at the last 20 and 30 days and then continue made histology preparation with HE staining. The examination result shows by the microscopic image of the group A wistar rats aortic are normal. Group B showed a layer of foam cells in the tunica intima media. Group C showed foam cells in the intima and the media have started to protrude into the lumen. As a conclusion the wistar rats that are exposed by cigarrete smoke during 20 to 30 days showed a fatty streak (foam cell) on tunica intima and media aortic as early lesions in the process of atherosclerosis. Keywords: atherosclerosis, cigarette. Abstrak: Rokok merupakan salah satu faktor pencetus terjadinya aterosklerosis. Aterosklerosis ditandai oleh adanya plak di arteri yang dapat menyebabkan penyempitan pada pembuluh darah. Aterosklerosis sering terjadi pada pembuluh darah aorta. Tujuan penelitian ini untuk dapat melihat gambaran histopatologi aorta tikus wistar setelah dipapar dengan asap rokok. Penelitian eksperimental ini dilakukan selama 5 bulan dengan menggunakan 10 ekor tikus wistar yang dibagi dalam 3 kelompok. Kelompok A kontrol negatif (2 ekor). Kelompok B dipapari asap rokok sebanyak 24 batang perhari selama 20 hari (4 ekor). Kelompok C dipapari asap rokok sebanyak 24 batang perhari selama 30 hari (4ekor). Tikus diotopsi pada hari ke 20 dan 30 dan dibuat preparat histologi dengan pengecatan HE. Hasil pemeriksaan menunjukkan gambaran mikroskopik aorta tikus wistar kelompok A normal. Kelompok B menunjukkan adanya sel busa pada lapisan tunika intima, sampai tunika media. Kelompok C menunjukkan sel busa pada tunika intima sampai media dan sudah mulai menonjol ke lumen. Simpulan: tikus wistar yang dipapari asap rokok selama 20 sampai 30 hari menunjukkan adanya fatty streak (selbusa) pada tunika intima dan media aorta sebagai lesi awal dalam proses aterosklerosis. Kata Kunci: aterosklerosis, rokok.