The Effect of Quercetin Supplementation on Inflammatory Indicators and Lipid Profile of Patients with Metabolic Syndrome; A Systematic Review

Introduction: Metabolic syndrome is a cluster of disorders including high blood pressure,abdominal obesity, high levels of triglycerides, impaired fasting glucose and low levels of HDLcholesterol, which may cause different risks. Quercetin, as an important flavonoid, has variousproperties such as lowering blood pressure, lowering blood lipids, reducing hyperglycemia,antioxidant, anti-inflammatory and heart protecting effects. The aim of this review study is toinvestigate the effect of quercetin supplementation on inflammatory indicators and lipid profileof patients with metabolic syndrome.Search Method: This systematic review study was conducted through an advanced search inPubmed, Scopus, Medline, Web of Science and GoogleScholar search engine. The keywordsused include Quercetin, Inflammatory Factors, Lipid Profile, Metabolic Syndrome andreviewed articles were clinical trials from ۲۰۱۵ to November ۲۰۲۲. Also, to ensure thecompleteness of the search results, the sources of the articles were also examined. Afterremoving the duplicate titles using EndNote software and checking the titles and abstracts, therelated articles were reviewed by the researchers using the JBI tool. After checking the qualityof the articles, the findings were entered in the desired checklist.Results: Quercetin reduces the level of total cholesterol and LDL cholesterol by weakeningthe proliferation-activating receptor α, the protein that binds to the sterol regulatory element ۱cin the liver and reducing acetyl-CoA carboxylase. In the reviewed studies, no positive effect ofquercetin on HDL cholesterol level was observed. The level of CRP is also reduced as anindicator of heart problems through the reduction of inflammatory enzymes. By inhibiting theactivity of NF-kB in pancreatic cells, quercetin reduces the production of leukotriene B۴ inleukocytes and suppresses the production of Nitric Oxide and inhibits the production ofinflammatory cytokines, and as a result, it affects the inflammatory indicators.Conclusion: Quercetin supplementation significantly reduced total cholesterol, LDLcholesterol and CRP levels in patients with metabolic syndrome and related disorders, but hadno effect on triglyceride, HDL cholesterol, IL-۶ and TNF-α. However, more clinical trialsshould be conducted to determine the definitive effectiveness of quercetin on metabolicsyndrome.

کلیدواژه ها:

Quercetin ، Inflammatory Indicators ، Lipid profile ، Metabolic Syndrome