Immunomodulatory and Preventive Effects of Olive Leaf Tea Against COVID-19

NCT05222347 | Completed DMC

• 1 other identifier: SBUSAH GETAT 2020-011
• Study Type: observational
• Target: 249
• Locations: 1 country
• Sites: 1

Brief Summary

During the Coronavirus Disease-2019 (COVID-19) pandemic, in addition to the current measures, boosting the immune system seems to be one of preventive measures that can be taken against COVID-19 infection. Various natural agents have been recommended to boost the immune system. The aim of this study was to investigate the possible immunomodulatory and preventive effects of Olive Leaf Tea (OLT) drinking with regards to COVID-19 infection. The study was conducted among 249 workers in a tractor factory where OLT was served. Of the 249 workers, 168 of them were OLT drinkers and 81 were not OLT drinkers. Drinking at least one cup of OLT per day for a minimum of one month was the inclusion criteria used in the study. The workers with a history of infection or vaccination of COVID-19 were excluded. Lymphocyte subsets, IL2, INF-gamma, specific IgM, and IgG levels were analyzed in all the study subjects. The results showed higher values of CD3-/CD16/56 (NK) cells, CD3+/CD16/56 (NKT) cells, total NK (NK+NKT) cells, and serum IFN-gamma and IL-2 levels in OLT drinkers as compared to the nondrinkers. These immune changes are indicative of immune defense mechanisms. Although all the OLT drinkers and non-drinkers reported no history of COVID-19, specific COVID-19 IgG levels were found positive in 60% of OLT drinkers and 38% OLT non-drinkers. There were significant negative correlations between age and NK cells, number of cigarettes smoked and NK cells, number of cigarettes smoked and TNK; and there were positive correlations between OLT drinking frequency and TNF-alpha, IL-2 and IFN-gamma. Also, serum creatinine levels in OLT non-drinkers were found significantly higher than in the OLT drinkers. In conclusion, drinking OLT may contribute fighting against COVID-19 by boosting the innate immune system.

Conditions

Immunomodulation

Outcome Measures

Primary Outcomes (1)

• Olive Leaf Tea increase immune force and prevent COVID-19 infection

  One year

Study Arms (2)

Comparison of biochemical parameters of OLT drinkers

Compared biochemical parameters of OLT smokers and nonsmokers

Dietary Supplement: Olive Leaf Tea

Comparison of biochemical parameters of OLT nondrinkers

Compared biochemical parameters of OLT smokers and nonsmokers

Dietary Supplement: Olive Leaf Tea

Interventions

Olive Leaf Tea DIETARY_SUPPLEMENT

Olive-leaf tea (OLT) is widely used in the traditional medicine in the Mediterranean region. Due to the high concentration of phenolic compounds, of which most abundant is oleuropein, interest in olive leaf has increased recently \[22, 23\]. The components of the olive leaves are known for their immune-modulatory, anti-inflammatory, antioxidant, hypoglycemic, antihypertensive, antimicrobial, and anti-atherosclerotic effects \[24, 25\]. Although its antiviral mechanism of action is not fully known, many studies have been conducted on the antiviral effects of olive leaf extract .

Comparison of biochemical parameters of OLT drinkers; Comparison of biochemical parameters of OLT nondrinkers

Eligibility Criteria

• Age: 20 Years - 60 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• Sampling Method: Probability Sample

Study Population

workers at the Tumosan Konya tractor factory

You may qualify if:

• Health male subjects aged between 20-60

You may not qualify if:

• Those who drank less than three cups of OLT a day were excluded from the study.

Sponsors & Collaborators

• Bezmialem Vakif University: lead
• Albayraklar Foundation: collaborator

Study Sites (1)

Tumosan Konya Tractor Factory

Konya, Selcuklu, 42250, Turkey (Türkiye)

Location

Related Publications (1)

• Kocyigit A, Guler EM, Irban A, Kiran B, Atayoglu AT. Assessment of Association Between the Potential Immunomodulatory Activity and Drinking Olive Leaf Tea in the Coronavirus Disease-2019 Pandemic: An Observational Study. J Integr Complement Med. 2022 Dec;28(12):940-947. doi: 10.1089/jicm.2022.0554. Epub 2022 Sep 16.

  PMID: 36112183 DERIVED

Study Officials

• Eray M. Guler, Assoc. Prof.

  University of Health Sciences Turkey, Hamidiye School of Medicine, Dept. of Medical Biochemistry

  PRINCIPAL INVESTIGATOR

• Arzu Irban, Professor

  University of Health Sciences Turkey, Hamidiye School of Medicine, Department of Anesthesiology,

  PRINCIPAL INVESTIGATOR

• Bayram Kiran, Professor

  Kastamonu University, Faculty of Engineering and Architecture, Dept. of Genetics and Bioengineering

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 1, 2022
• First Posted: February 3, 2022
• Study Start: September 1, 2020
• Primary Completion: March 4, 2021
• Study Completion: September 5, 2021
• Last Updated: February 3, 2022

Record last verified: 2022-02

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)