552 www.bsmiab.org/jabet Faustin et al., J Adv Biotechnol Exp Ther. 2023 Sep; 6(3): 552-563 Effect of white tea (Camellia sinensis) leaf extract on cigarette smoke and high-fat diet-induced atherosclerosis in Wistar rats Jennifer Faustin 1, * , Bahrudin 2 , Neni Susilaningsih 3 , Muflihatul Muniroh 4 , Endang Mahati 4 , Hermawan Istiadi 5 1 Graduate School of Biomedical Science, Faculty of Medicine, Diponegoro University, Semarang, Central Java, Indonesia 2 Department of Histology, Faculty of Medicine, Diponegoro University, Semarang, Central Java, Indonesia 3 Department of Cardiology, Faculty of Medicine, Diponegoro University, Central Java, Indonesia 4 Department of Pharmacology and Therapeutics, Faculty of Medicine, Diponegoro University, Semarang, Central Java, Indonesia 5 Department of Pathological Anatomy, Faculty of Medicine, Diponegoro University, Semarang, Central Java, Indonesia ABSTRACT Atherosclerosis is a complex pathological process begins with endothelial dysfunction, one of which is triggered by an inflammatory process due to increased levels of low- density lipoprotein (LDL) cholesterol and exposure to cigarette smoke. White tea leaf (Camellia sinensis) shows an anti-inflammatory effect which has not been known for its effect on the atherosclerotic process. The aim of this study is to determine the effect of Camellia sinensis leaf extract on IL-6 levels, foam cell count, and the ratio of intima-media thickness of cigarette smoke and high-fat diet-induced atherosclerosis in Wistar rats. Thirty male Wistar rats were randomly divided into 5 groups namely HC (healthy control), NC (negative control), WT100, WT200, and WT400 (treated with white tea leaf extract 100, 200, and 400 mg/kgBW/day, respectively). IL-6 levels were measured by the ELISA method. At 400x microscope magnification, foam cell count and intima-media thickness ratio were seen in aortic tissue. Administration of graded doses of white tea leaf extract in groups WT100, WT200, WT400 significantly reduced IL-6 levels, foam cell count, and intima-media thickness ratio of abdominal aorta compared to the NC group. These results suggest that white tea leaf extract may decrease levels of IL-6, foam cell count, and intima-media thickness ratio in atherosclerosis-induced Wistar rats. INTRODUCTION Atherosclerosis is a complicated pathological process that primarily results from cholesterol buildup, endothelial dysfunction, infiltration of inflammatory cells, and migration of vascular smooth muscle cells [1]. It is characterized by structural abnormalities in the intima and media arteries. Certain factors or behaviors, such as high levels of low-density lipoprotein (LDL) cholesterol, low blood levels of high- density lipoprotein (HDL), hypertension, smoking, diabetes mellitus, obesity, and sedentary lifestyles that increase the risk of vascular endothelial dysfunction and atherosclerosis, may increase the likelihood of developing atherosclerosis [2]. This increases the risk of stroke, myocardial infarction, and other cardiovascular diseases. One of the key risk factors for the early initiation of atherosclerosis, which starts the inflammatory reactions in the microvascular system, is hypercholesterolemia and exposure to cigarette smoke [3–5]. The release of pro-inflammatory cytokines like interleukin-6 (IL-6) is linked to abnormalities in blood flow and endothelial cell stretching. Vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1) expression rises in response to IL-6 binding to its receptors [6]. Monocytes are drawn in by the expression of VCAM and ICAM-1, and they later *Corresponding author Jennifer Faustin, PhD Graduate School of Biomedical Science, Faculty of Medicine Diponegoro University, Semarang, Central Java, Indonesia e-mail: dean@fk.undip.ac.id Academic editor Md Jamal Uddin, PhD ABEx Bio-Research Center, Dhaka 1230, Bangladesh Article info Received: 28 April 2023 Accepted: 08 June 2023 Published: 22 June 2023 Keywords Atherosclerosis, Camellia sinensis, Cigarette smoke, High-fat diet, White tea This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non- commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. ORIGINAL ARTICLE J Adv Biotechnol Exp Ther. 2023 Sep; 6(3): 552-563 eISSN: 2616-4760, https://doi.org/10.5455/jabet.2023.d148 Published by www.bsmiab.org