Eun-Yong Choi1, Hansongyi Lee2, Jong Shin Woo1, Hyun Hee Jang1, Seung Joon Hwang1, Hyun Soo Kim1, Woo-Sik Kim1, Young-Seol Kim3, Ryowon Choue2, Yong-Jun Cha4, Jung-Eun Yim4, Weon Kim5. 1. Division of Cardiology, Department of Internal Medicine, Kyung Hee University College of Medicine, Kyung Hee University, Seoul, Republic of Korea. 2. Department of Medical Nutrition, Graduate School of East-West Medical Science, Kyung Hee University, Yongin 447-701, Republic of Korea; Research Institute of Medical Nutrition, Kyung Hee University, Seoul 130-701, Republic of Korea. 3. Division of Endocrinology, Department of Internal Medicine, Kyung Hee University College of Medicine, Kyung Hee University, Seoul, Republic of Korea. 4. Department of Food and Nutrition, Changwon National University, Changwon, Republic of Korea. 5. Division of Cardiology, Department of Internal Medicine, Kyung Hee University College of Medicine, Kyung Hee University, Seoul, Republic of Korea. Electronic address: mylovekw@hanmail.net.
Abstract
OBJECTIVES: Acute or chronic intake of polyphenol-rich foods has been reported to improve endothelial function. Quercetin, found abundantly in onion, is a potent antioxidant flavonoid. The aim of this study was to investigate whether consumption of onion peel extract (OPE) improves endothelial function in healthy overweight and obese individuals. METHODS: This was a randomized double-blind, placebo-controlled study. Seventy-two healthy overweight and obese participants were randomly assigned to receive a red, soft capsule of OPE (100 mg quercetin/d, 50 mg quercetin twice daily; n = 36 participants) or an identical placebo capsule (n = 36) for 12 wk. Endothelial function, defined by flow-mediated dilation (FMD), circulating endothelial progenitor cells (EPCs) by flow cytometry, and laboratory test were determined at baseline and after treatment. RESULTS: Baseline characteristics and laboratory findings did not significantly differ between the two groups. Compared with baseline values, the OPE group showed significantly improved FMD at 12 wk (from 12.5 ± 5.2 to 15.2 ± 6.1; P = 0.002), whereas the placebo group showed no difference. Nitroglycerin-mediated dilation did not change in either group. EPC counts (44.2 ± 25.6 versus 52.3 ± 18.6; P = 0.005) and the percentage of EPCs were significantly increased in the OPE group. When FMD was divided into quartiles, rate of patients with endothelial dysfunction defined as lowest quartile (cutoff value, 8.6%) of FMD improved from 26% to 9% by OPE. CONCLUSION: Medium-term administration of OPE an improvement in FMD and circulating EPCs.
RCT Entities:
OBJECTIVES: Acute or chronic intake of polyphenol-rich foods has been reported to improve endothelial function. Quercetin, found abundantly in onion, is a potent antioxidant flavonoid. The aim of this study was to investigate whether consumption of onion peel extract (OPE) improves endothelial function in healthy overweight and obese individuals. METHODS: This was a randomized double-blind, placebo-controlled study. Seventy-two healthy overweight and obeseparticipants were randomly assigned to receive a red, soft capsule of OPE (100 mg quercetin/d, 50 mg quercetin twice daily; n = 36 participants) or an identical placebo capsule (n = 36) for 12 wk. Endothelial function, defined by flow-mediated dilation (FMD), circulating endothelial progenitor cells (EPCs) by flow cytometry, and laboratory test were determined at baseline and after treatment. RESULTS: Baseline characteristics and laboratory findings did not significantly differ between the two groups. Compared with baseline values, the OPE group showed significantly improved FMD at 12 wk (from 12.5 ± 5.2 to 15.2 ± 6.1; P = 0.002), whereas the placebo group showed no difference. Nitroglycerin-mediated dilation did not change in either group. EPC counts (44.2 ± 25.6 versus 52.3 ± 18.6; P = 0.005) and the percentage of EPCs were significantly increased in the OPE group. When FMD was divided into quartiles, rate of patients with endothelial dysfunction defined as lowest quartile (cutoff value, 8.6%) of FMD improved from 26% to 9% by OPE. CONCLUSION: Medium-term administration of OPE an improvement in FMD and circulating EPCs.
Authors: Yawen Zeng; Yuping Li; Jiazhen Yang; Xiaoying Pu; Juan Du; Xiaomeng Yang; Tao Yang; Shuming Yang Journal: Evid Based Complement Alternat Med Date: 2017-02-05 Impact factor: 2.629
Authors: Regina Menezes; Ana Rodriguez-Mateos; Antonia Kaltsatou; Antonio González-Sarrías; Arno Greyling; Christoforos Giannaki; Cristina Andres-Lacueva; Dragan Milenkovic; Eileen R Gibney; Julie Dumont; Manuel Schär; Mar Garcia-Aloy; Susana Alejandra Palma-Duran; Tatjana Ruskovska; Viktorija Maksimova; Emilie Combet; Paula Pinto Journal: Nutrients Date: 2017-02-09 Impact factor: 5.717