Pomegranate Extract Improves IL-35 Expression & Forced Vital Capacity Ratio in Adults with Asthma 

by | Mar 13, 2023 | 2022, Asthma, Fruits and Vegetables, Lung Health, Polyphenols

Written by Taylor Woosley, Staff Writer. Based on asthma severity, there were statistically significant changes in FEV1, FEV1/FVC, and FEF25-75% in the pomegranate extract group with mild asthma severity (p = 0.02, p = 0.006, and p = 0.03, respectively). 

fruits and vegetablesAsthma is defined by episodic and reversible airway constriction and inflammation in response to infection, environmental allergens, and irritants1.  It is one of the most common chronic lung diseases in the United States, affecting approximately 8% of adults, or about 20 million individuals2. Genetic and epigenetic variations, social and environmental factors, and sex hormones are important factors observed in asthma incidence, prevalence, and severity3.

In traditional medicine, pomegranate has been used to treat diseases due to its anti-microbial, anti-inflammatory, and anti-viral properties4. It is a rich source of polyphenols such as ellagic acid and punicalagin, important bioactive constituents with the potential to reduce oxidative stress and inflammation5. Previous research has shown that punicalagin can repress ovalbumin-induced asthma and reduce cellular infiltration6.

Shateri et al. conducted a randomized, double-blind, placebo-controlled study to determine the impact of pomegranate extract on lung function parameters evaluated through spirometry, hs-CRP, pro-oxidant antioxidant balance (PAB), and IL-35 in subjects with mild and moderate allergic asthma. Subjects completed a questionnaire on demographic information and personal characteristics, such as age and onset of asthma, at baseline and end of trial. Physical activity was assessed at baseline and end of study through the international physical activity questionnaire. Allergic asthma was confirmed by measuring the total serum immunoglobulin E (IgE) levels.

Subjects (n=64) were included in the study if they were between the ages of 18 to 65 years old, who experienced persistent allergic asthma, with serum IgE levels ≥30 and a BMI below 30 kg/m2. Primary outcomes included changes in measurement of PAB, hs-CRP, IL-35, and spirometry tests, which were performed at the beginning of the study and the end of the 8th week. Blood samples were obtained at baseline and the end of the study. Forced expiratory flow 25-75% (FEF25-75%), forced vital capacity (FVC), FEV1 and FEV1/FVC ratio were evaluated at the beginning and end of study.

Participants with persistent allergic asthma were categorized into two groups (mild and moderate) based on their severity (FEV1 ≥ 60%) and clinical symptoms based on the Global Initiative for Asthma (GINA) diagnostic criteria for asthma. Subjects were randomly divided into the pomegranate extract group (n=32) and placebo (n=32). Those in the pomegranate extract group consumed a capsule twice daily containing 250 mg of pomegranate seed extract, 2.1 µg of ellagic acid, 118.4 µg of punicalagin alpha, and 53 µg of punicalagin beta. The placebo capsule was identical in size and color to the pomegranate capsule, and both were consumed daily for 8 weeks.

Independent samples t-test or Mann-Whitney U was utilized to compare PAB, FEV1/FVC ratio, RVC, FEF25-75%, FEV1, IL-25, and serum hs-CRP levels between the pomegranate extract group and the control. Furthermore, subgroup analysis was conducted based on asthma severity. The mean and standard deviation of participants’ age was 38.44 ± 11.90 years. 50% of participants had mild asthma and the rest had moderate asthma. Significant findings of the study are as follows:

  • No statistically significant differences were noted between the intervention group and the control group regarding IL-35 and serum hs-CRP levels (p = 0.055 and p = 0.277, respectively). However, at the end of the 8-weeks study, the change levels of IL-35 between the two groups were statistically significant (p = 0.026).
  • Results of subgroup analysis based on asthma severity show that the changes in IL-35 were statistically significant only in the intervention group with mild asthma severity (p = 0.03). Also, the change levels of IL-35 were statistically significant in mild asthma severity between the intervention and control groups (p = 0.02).
  • Results indicate that FEF25-75%, FEV1/FVC ratio, and FEV1 increased in the intervention group (p = 0.012, p = 0.001, and p = 0.031, respectively). Additionally, the levels of change in the FEV1/FVC ratio between the two groups were statistically significant (p = 0.023).

Findings of the study suggest that supplementation with pomegranate extract significantly increased levels of IL-35, which has anti-inflammatory properties. Additionally, improvements in lung function parameters such as FEV1/FVC ratios in subjects were noted. Study limitations include the short study duration, lack of measuring other inflammatory parameters, and the inability to measure plasma polyphenol derivatives’ levels of pomegranate extract in participants.

Source: Shateri, Zainab, Seyed Ahmad Hosseini, Farhad Abolnezhadian, Elham Maraghi, Maryam Haddadzadeh Shoushtari, and Marzie Zilaee. “Pomegranate extract supplementation improves lung function parameters and IL-35 expression in participants with mild and moderate persistent allergic asthma: A randomized, double-blind, placebo-controlled trial.” Frontiers in Nutrition 9 (2022).

© 2022 Shateri, Hosseini, Abolnezhadian, Maraghi, Haddadzadeh Shoushtari and Zilaee. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

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Posted March 13, 2023.

Taylor Woosley studied biology at Purdue University before becoming a 2016 graduate of Columbia College Chicago with a major in Writing. She currently resides in Glen Ellyn, IL.

References:

  1. Patel SJ, Teach SJ. Asthma. Pediatr Rev. Nov 2019;40(11):549-567. doi:10.1542/pir.2018-0282
  2. Wu TD, Brigham EP, McCormack MC. Asthma in the Primary Care Setting. The Medical clinics of North America. May 2019;103(3):435-452. doi:10.1016/j.mcna.2018.12.004
  3. Chowdhury NU, Guntur VP, Newcomb DC, Wechsler ME. Sex and gender in asthma. Eur Respir Rev. Dec 31 2021;30(162)doi:10.1183/16000617.0067-2021
  4. Hosseini SA, Shateri Z, Abolnezhadian F, Maraghi E, Haddadzadeh Shoushtari M, Zilaee M. Does pomegranate extract supplementation improve the clinical symptoms of patients with allergic asthma? A double-blind, randomized, placebo-controlled trial. Front Pharmacol. 2023;14:1109966. doi:10.3389/fphar.2023.1109966
  5. Zeng Y, Zhao H, Zhang T, et al. Lung-protective effect of Punicalagin on LPS-induced acute lung injury in mice. Biosci Rep. Jan 28 2022;42(1)doi:10.1042/bsr20212196
  6. Yu L, Li J. Punicalagin attenuated allergic airway inflammation via regulating IL4/IL-4Rα/STAT6 and Notch- GATA3 pathways. Acta Pharm. Dec 1 2022;72(4):561-573. doi:10.2478/acph-2022-0038