Phytochemical-rich medicinal plant extracts suppress bacterial antigens-induced inflammation in human tonsil epithelial cells
Background Pharyngitis is an inflammatory condition of the pharynx and associated structures commonly caused by the Group A streptococci (GAS). There is a growing interest in discovering plant-based anti-inflammatory compounds as potential alternatives to conventional drugs. This study evaluated ant...
Main Authors: | , , |
---|---|
Format: | Article |
Language: | English |
Published: |
PeerJ Inc.
2017-06-01
|
Series: | PeerJ |
Subjects: | |
Online Access: | https://peerj.com/articles/3469.pdf |
_version_ | 1797419958669410304 |
---|---|
author | Niluni M. Wijesundara Satvir Sekhon-Loodu HP Vasantha Rupasinghe |
author_facet | Niluni M. Wijesundara Satvir Sekhon-Loodu HP Vasantha Rupasinghe |
author_sort | Niluni M. Wijesundara |
collection | DOAJ |
description | Background Pharyngitis is an inflammatory condition of the pharynx and associated structures commonly caused by the Group A streptococci (GAS). There is a growing interest in discovering plant-based anti-inflammatory compounds as potential alternatives to conventional drugs. This study evaluated anti-inflammatory activity of phytochemical-rich extracts prepared from 12 herbal plants using human tonsil epithelial cells (HTonEpiC) in vitro. Methods The HTonEpiC were induced by a mixture of lipoteichoic acid (LTA) and peptidoglycan (PGN) (10 µg/mL; bacterial antigens) for 4 h and then exposed to ethanol extracts (EE) or aqueous extracts (AE) for 20 h. The secretion of four pro-inflammatory cytokines was measured using enzyme-linked immunosorbent assays (ELISA). Total phenolic and total flavonoid contents of the extracts were determined using spectrophotometric methods. Results The herbal plant extracts (≤5 µg/mL) were not cytotoxic to HTonEpiC. The extracts exhibited a broad range of reduction (1.2%–92.6%) of secretion of interleukin-8 (IL-8), human beta defensin-2 (hBD-2), epithelial-derived neutrophil activating protein-78 (ENA-78), and granulocyte chemotactic protein-2 (GCP-2). Both EE and AE of clove, ginger, and echinacea flower and EE from danshen root significantly inhibited the pro-inflammatory cytokine production as induced by LTA and PGN in HTonEpiCs at the concentrations of 1 and 5 µg/mL. Discussion Our observations indicate that danshen root, clove, ginger, and echinacea flower extracts exhibit an anti-inflammatory effect in HTonEpiCs. The most efficacious extracts from danshen root, clove, ginger and echinacea flowers have potential to be used as natural sources for developing phytotherapeutic products in the management of painful inflammation due to streptococcal pharyngitis. |
first_indexed | 2024-03-09T06:54:42Z |
format | Article |
id | doaj.art-fb8972d1246f49608e2b51680d525ac0 |
institution | Directory Open Access Journal |
issn | 2167-8359 |
language | English |
last_indexed | 2024-03-09T06:54:42Z |
publishDate | 2017-06-01 |
publisher | PeerJ Inc. |
record_format | Article |
series | PeerJ |
spelling | doaj.art-fb8972d1246f49608e2b51680d525ac02023-12-03T10:07:55ZengPeerJ Inc.PeerJ2167-83592017-06-015e346910.7717/peerj.3469Phytochemical-rich medicinal plant extracts suppress bacterial antigens-induced inflammation in human tonsil epithelial cellsNiluni M. Wijesundara0Satvir Sekhon-Loodu1HP Vasantha Rupasinghe2Department of Plant, Food, and Environmental Sciences, Faculty of Agriculture, Dalhousie University, Truro, NS, CanadaDepartment of Plant, Food, and Environmental Sciences, Faculty of Agriculture, Dalhousie University, Truro, NS, CanadaDepartment of Plant, Food, and Environmental Sciences, Faculty of Agriculture, Dalhousie University, Truro, NS, CanadaBackground Pharyngitis is an inflammatory condition of the pharynx and associated structures commonly caused by the Group A streptococci (GAS). There is a growing interest in discovering plant-based anti-inflammatory compounds as potential alternatives to conventional drugs. This study evaluated anti-inflammatory activity of phytochemical-rich extracts prepared from 12 herbal plants using human tonsil epithelial cells (HTonEpiC) in vitro. Methods The HTonEpiC were induced by a mixture of lipoteichoic acid (LTA) and peptidoglycan (PGN) (10 µg/mL; bacterial antigens) for 4 h and then exposed to ethanol extracts (EE) or aqueous extracts (AE) for 20 h. The secretion of four pro-inflammatory cytokines was measured using enzyme-linked immunosorbent assays (ELISA). Total phenolic and total flavonoid contents of the extracts were determined using spectrophotometric methods. Results The herbal plant extracts (≤5 µg/mL) were not cytotoxic to HTonEpiC. The extracts exhibited a broad range of reduction (1.2%–92.6%) of secretion of interleukin-8 (IL-8), human beta defensin-2 (hBD-2), epithelial-derived neutrophil activating protein-78 (ENA-78), and granulocyte chemotactic protein-2 (GCP-2). Both EE and AE of clove, ginger, and echinacea flower and EE from danshen root significantly inhibited the pro-inflammatory cytokine production as induced by LTA and PGN in HTonEpiCs at the concentrations of 1 and 5 µg/mL. Discussion Our observations indicate that danshen root, clove, ginger, and echinacea flower extracts exhibit an anti-inflammatory effect in HTonEpiCs. The most efficacious extracts from danshen root, clove, ginger and echinacea flowers have potential to be used as natural sources for developing phytotherapeutic products in the management of painful inflammation due to streptococcal pharyngitis.https://peerj.com/articles/3469.pdfHerbsPainLipoteichoic acidStreptococcal pharyngitisPeptidoglycanCytokines |
spellingShingle | Niluni M. Wijesundara Satvir Sekhon-Loodu HP Vasantha Rupasinghe Phytochemical-rich medicinal plant extracts suppress bacterial antigens-induced inflammation in human tonsil epithelial cells PeerJ Herbs Pain Lipoteichoic acid Streptococcal pharyngitis Peptidoglycan Cytokines |
title | Phytochemical-rich medicinal plant extracts suppress bacterial antigens-induced inflammation in human tonsil epithelial cells |
title_full | Phytochemical-rich medicinal plant extracts suppress bacterial antigens-induced inflammation in human tonsil epithelial cells |
title_fullStr | Phytochemical-rich medicinal plant extracts suppress bacterial antigens-induced inflammation in human tonsil epithelial cells |
title_full_unstemmed | Phytochemical-rich medicinal plant extracts suppress bacterial antigens-induced inflammation in human tonsil epithelial cells |
title_short | Phytochemical-rich medicinal plant extracts suppress bacterial antigens-induced inflammation in human tonsil epithelial cells |
title_sort | phytochemical rich medicinal plant extracts suppress bacterial antigens induced inflammation in human tonsil epithelial cells |
topic | Herbs Pain Lipoteichoic acid Streptococcal pharyngitis Peptidoglycan Cytokines |
url | https://peerj.com/articles/3469.pdf |
work_keys_str_mv | AT nilunimwijesundara phytochemicalrichmedicinalplantextractssuppressbacterialantigensinducedinflammationinhumantonsilepithelialcells AT satvirsekhonloodu phytochemicalrichmedicinalplantextractssuppressbacterialantigensinducedinflammationinhumantonsilepithelialcells AT hpvasantharupasinghe phytochemicalrichmedicinalplantextractssuppressbacterialantigensinducedinflammationinhumantonsilepithelialcells |