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Smyth JS, Truong JK, Rao A, Lin R, Foulke-Abel J, Adorini L, Donowitz M, Dawson PA, Keely SJ. Farnesoid X receptor enhances epithelial ACE2 expression and inhibits virally induced IL-6 secretion: implications for intestinal symptoms of SARS-CoV-2. Am J Physiol Gastrointest Liver Physiol 2023; 325:G446-G452. [PMID: 37697930 PMCID: PMC10887846 DOI: 10.1152/ajpgi.00099.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 09/01/2023] [Accepted: 09/01/2023] [Indexed: 09/13/2023]
Abstract
Intestinal inflammation and diarrhea are often associated with SARS-CoV-2 infection. The angiotensin converting enzyme 2 (ACE2) receptor plays a key role in SARS-CoV-2 pathogenesis, facilitating entry of the virus into epithelial cells, while also regulating mucosal inflammatory responses. Here, we investigated roles for the nuclear bile acid receptor farnesoid X receptor (FXR) in regulating ACE2 expression and virally mediated inflammatory responses in intestinal epithelia. Human colonic or ileal enteroids and cultured T84 and Caco-2 monolayers were treated with the FXR agonists, obeticholic acid (OCA) or GW4064, or infected with live SARS-CoV-2 (2019-nCoV/USA_WA1/2020). Changes in mRNA, protein, or secreted cytokines were measured by qPCR, Western blotting, and ELISA. Treatment of undifferentiated colonic or ileal enteroids with OCA increased ACE2 mRNA by 2.1 ± 0.4-fold (n = 3; P = 0.08) and 2.3 ± 0.2-fold (n = 3; P < 0.05), respectively. In contrast, ACE2 expression in differentiated enteroids was not significantly altered. FXR activation in cultured epithelial monolayers also upregulated ACE2 mRNA, accompanied by increases in ACE2 expression and secretion. Further experiments revealed FXR activation to inhibit IL-6 release from both Caco-2 cells infected with SARS-CoV-2 and T84 cells treated with the viral mimic, polyinosinic:polycytidylic acid, by 46 ± 12% (n = 3, P < 0.05) and 35 ± 6% (n = 8; P < 0.01), respectively. By virtue of its ability to modulate epithelial ACE2 expression and inhibit virus-mediated proinflammatory cytokine release, FXR represents a promising target for the development of new approaches to prevent intestinal manifestations of SARS-CoV-2.NEW & NOTEWORTHY Activation of the nuclear bile acid receptor, farnesoid X receptor (FXR), specifically upregulates ACE2 expression in undifferentiated colonic epithelial cells and inhibits virus-induced proinflammatory cytokine release. By virtue of these actions FXR represents a promising target for the development of new approaches to prevent intestinal manifestations of SARS-CoV-2 infection.
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Affiliation(s)
- Jessica S Smyth
- School of Pharmacy and Biomolecular Sciences, The Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin, Ireland
| | - Jennifer K Truong
- Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, Georgia, United States
| | - Anuradha Rao
- Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, Georgia, United States
| | - Ruxian Lin
- Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, Georgia, United States
| | - Jennifer Foulke-Abel
- Gastroenterology Division, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - Luciano Adorini
- Intercept Pharmaceuticals, San Diego, California, United States
| | - Mark Donowitz
- Gastroenterology Division, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
- Department of Physiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - Paul A Dawson
- Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, Georgia, United States
| | - Stephen J Keely
- School of Pharmacy and Biomolecular Sciences, The Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin, Ireland
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Gao Q, Fan T, Luo S, Zheng J, Zhang L, Cao L, Zhang Z, Li L, Huang Z, Zhang H, Huang L, Xiao Q, Qiu F. Lactobacillus gasseri LGV03 isolated from the cervico-vagina of HPV-cleared women modulates epithelial innate immune responses and suppresses the growth of HPV-positive human cervical cancer cells. Transl Oncol 2023; 35:101714. [PMID: 37331103 PMCID: PMC10366645 DOI: 10.1016/j.tranon.2023.101714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Revised: 12/24/2022] [Accepted: 06/07/2023] [Indexed: 06/20/2023] Open
Abstract
Persistent human papillomavirus (HPV) infections is necessary for the development of cervical cancers. An increasing number of retrospective studies have found the depletion of Lactobacillus microbiota in the cervico-vagina facilitate HPV infection and might be involved in viral persistence and cancer development. However, there have been no reports confirming the immunomodulatory effects of Lactobacillus microbiota isolated from cervico-vaginal samples of HPV clearance in women. Using cervico-vaginal samples from HPV persistent infection and clearance in women, this study investigated the local immune properties in cervical mucosa. As expected, type I interferons, such as IFN-α and IFN-β, and TLR3 globally downregulated in HPV+ persistence group. Luminex cytokine/chemokine panel analysis revealed that L. jannaschii LJV03, L. vaginalis LVV03, L. reuteri LRV03, and L. gasseri LGV03 isolated from cervicovaginal samples of HPV clearance in women altered the host's epithelial immune response, particularly L. gasseri LGV03. Furthermore, L. gasseri LGV03 enhanced the poly (I:C)-induced production of IFN by modulating the IRF3 pathway and attenuating poly (I:C)-induced production of proinflammatory mediators by regulating the NF-κB pathway in Ect1/E6E7 cells, indicating that L. gasseri LGV03 keeps the innate system alert to potential pathogens and reduces the inflammatory effects during persistent pathogen infection. L. gasseri LGV03 also markedly inhibited the proliferation of Ect1/E6E7 cells in a zebrafish xenograft model, which may be attributed to an increased immune response mediated by L. gasseri LGV03.
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Affiliation(s)
- Qiong Gao
- Department of Gynecology, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen 518000, China
| | - Tao Fan
- Department of Obstetrics, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen 518003, China
| | - Siying Luo
- Department of Gynecology, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen 518000, China
| | - Jieting Zheng
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
| | - Lin Zhang
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
| | - Longbing Cao
- Department of Laboratory Medicine, The Seventh Affiliated Hospital of Southern Medical University, Foshan, Guangdong 528244, China
| | - Zikang Zhang
- Department of Laboratory Medicine, The Seventh Affiliated Hospital of Southern Medical University, Foshan, Guangdong 528244, China
| | - Li Li
- Department of Gynecology, University of Chinese Academy of Sciences Shenzhen Hospital (Guangming), Shenzhen, 518000, China
| | - Zhu Huang
- Department of Gynecology, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen 518000, China
| | - Huifen Zhang
- Department of Obstetrics, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen 518003, China
| | - Liuxuan Huang
- Department of Gynecology, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen 518000, China
| | - Qing Xiao
- Department of Gynecology, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen 518000, China
| | - Feng Qiu
- Department of Laboratory Medicine, The Seventh Affiliated Hospital of Southern Medical University, Foshan, Guangdong 528244, China.
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Lactic Acid Bacteria in Raw-Milk Cheeses: From Starter Cultures to Probiotic Functions. Foods 2022; 11:foods11152276. [PMID: 35954043 PMCID: PMC9368153 DOI: 10.3390/foods11152276] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 07/15/2022] [Accepted: 07/25/2022] [Indexed: 12/04/2022] Open
Abstract
Traditional cheeses produced from raw milk exhibit a complex microbiota, characterized by a sequence of different microorganisms from milk coagulation and throughout maturation. Lactic acid bacteria (LAB) play an essential role in traditional cheese making, either as starter cultures that cause the rapid acidification of milk or as secondary microbiota that play an important role during cheese ripening. The enzymes produced by such dynamic LAB communities in raw milk are crucial, since they support proteolysis and lipolysis as chief drivers of flavor and texture of cheese. Recently, several LAB species have been characterized and used as probiotics that successfully promote human health. This review highlights the latest trends encompassing LAB acting in traditional raw milk cheeses (from cow, sheep, and goat milk), and their potential as probiotics and producers of bioactive compounds with health-promoting effects.
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Wang Y, Moon A, Huang J, Sun Y, Qiu HJ. Antiviral Effects and Underlying Mechanisms of Probiotics as Promising Antivirals. Front Cell Infect Microbiol 2022; 12:928050. [PMID: 35734576 PMCID: PMC9207339 DOI: 10.3389/fcimb.2022.928050] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 05/10/2022] [Indexed: 11/13/2022] Open
Abstract
Probiotics exert a variety of beneficial effects, including maintaining homeostasis and the balance of intestinal microorganisms, activating the immune system, and regulating immune responses. Due to the beneficial effects of probiotics, a wide range of probiotics have been developed as probiotic agents for animal and human health. Viral diseases cause serious economic losses to the livestock every year and remain a great challenge for animals. Moreover, strategies for the prevention and control of viral diseases are limited. Viruses enter the host through the skin and mucosal surface, in which are colonized by hundreds of millions of microorganisms. The antiviral effects of probiotics have been proved, including modulation of chemical, microbial, physical, and immune barriers through various probiotics, probiotic metabolites, and host signaling pathways. It is of great significance yet far from enough to elucidate the antiviral mechanisms of probiotics. The major interest of this review is to discuss the antiviral effects and underlying mechanisms of probiotics and to provide targets for the development of novel antivirals.
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Affiliation(s)
| | | | | | - Yuan Sun
- *Correspondence: Hua-Ji Qiu, ; Yuan Sun,
| | - Hua-Ji Qiu
- *Correspondence: Hua-Ji Qiu, ; Yuan Sun,
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Kanmani P, Kim H. Probiotics counteract the expression of hepatic profibrotic genes via the attenuation of TGF-β/SMAD signaling and autophagy in hepatic stellate cells. PLoS One 2022; 17:e0262767. [PMID: 35051234 PMCID: PMC8775563 DOI: 10.1371/journal.pone.0262767] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 01/04/2022] [Indexed: 12/19/2022] Open
Abstract
Hepatic fibrosis is caused by the increased accumulation and improper degradation of extracellular matrix (ECM) proteins in the liver. Hepatic stellate cells (HSCs) activation is a key process in initiating hepatic fibrosis and can be ameliorated by the administration of probiotic strains. This study hypothesized that LAB strains (Lactiplantibacillus plantarum, Lactobacillus brevis, and Weissella cibaria) might attenuate pro-fibrogenic cytokine TGF-β mediated HSCs activation and induce collagen deposition, expression of other fibrogenic/inflammatory markers, autophagy, and apoptotic processes in vitro. Few studies have evaluated the probiotic effects against fibrogenesis in vitro. In this study, TGF-β exposure increased collagen deposition in LX-2 cells, but this increase was diminished when the cells were pretreated with LAB strains before TGF-β stimulation. TGF-β not only increased collagen deposition, but it also significantly upregulated the mRNA levels of Col1A1, alpha-smooth muscle actin (α-SMA), matrix metalloproteinases-2 (MMP-2), IL-6, CXCL-8, CCL2, and IL-1β in LX-2 cells. Pretreatment of the cells with LAB strains counteracted the TGF-β-induced pro-fibrogenic and inflammatory markers by modulating SMAD-dependent and SMAD-independent TGF-β signaling. In addition, LX-2 cells exposed to TGF-β induced the autophagic and apoptotic associated proteins that were also positively regulated by the LAB strains. These findings suggest that LAB can attenuate TGF-β signaling that is associated with liver fibrogenesis.
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Affiliation(s)
- Paulraj Kanmani
- Department of Korean Medicine, Dongguk University, Goyang, Republic of Korea
- Department of Medicine, University of Illinois, Chicago, Illinois, United States of America
| | - Hojun Kim
- Department of Korean Medicine, Dongguk University, Goyang, Republic of Korea
- * E-mail:
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Kober AKMH, Riaz Rajoka MS, Mehwish HM, Villena J, Kitazawa H. Immunomodulation Potential of Probiotics: A Novel Strategy for Improving Livestock Health, Immunity, and Productivity. Microorganisms 2022; 10:microorganisms10020388. [PMID: 35208843 PMCID: PMC8878146 DOI: 10.3390/microorganisms10020388] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 01/23/2022] [Accepted: 02/03/2022] [Indexed: 02/06/2023] Open
Abstract
Over the past decade, the use of probiotics as feed supplements in animal production has increased considerably due to the ban on antibiotic growth promoters in livestock. This review provides an overview of the current situation, limitation, and prospects for probiotic formulations applied to livestock. Recently, the use of probiotics in livestock has been suggested to significantly improve their health, immunity, growth performance, nutritional digestibility, and intestinal microbial balance. Furthermore, it was reported that the use of probiotics in animals was helpful in equilibrating their beneficial microbial population and microbial turnover via stimulating the host immune response through specific secretions and competitive exclusion of potentially pathogenic bacteria in the digestive tract. Recently, there has been great interest in the understanding of probiotics targeted diet and its ability to compete with harmful microbes and acquire their niches. Therefore, the present review explores the most commonly used probiotic formulations in livestock feed and their effect on animal health. In summary, this article provides an in-depth knowledge about the formulation of probiotics as a step toward a better alternative to antibiotic healthy growth strategies.
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Affiliation(s)
- A. K. M. Humayun Kober
- Laboratory of Animal Food Function, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (M.S.R.R.); (H.M.M.)
- Livestock Immunology Unit, International Education and Research Centre for Food and Agricultural Immunology, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan
- Department of Dairy and Poultry Science, Chittagong Veterinary and Animal Sciences University, Khulshi, Chittagong 4225, Bangladesh
- Correspondence: or (A.K.M.H.K.); (H.K.); Tel.: +880-1712-164794 (A.K.M.H.K.); +81-22-757-4372 (H.K.)
| | - Muhammad Shahid Riaz Rajoka
- Laboratory of Animal Food Function, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (M.S.R.R.); (H.M.M.)
- Livestock Immunology Unit, International Education and Research Centre for Food and Agricultural Immunology, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan
| | - Hafiza Mahreen Mehwish
- Laboratory of Animal Food Function, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (M.S.R.R.); (H.M.M.)
- Livestock Immunology Unit, International Education and Research Centre for Food and Agricultural Immunology, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan
| | - Julio Villena
- Laboratory of Immunobiotechnology, Reference Centre for Lactobacilli (CERELA-CONICET), Tucuman 4000, Argentina;
| | - Haruki Kitazawa
- Laboratory of Animal Food Function, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (M.S.R.R.); (H.M.M.)
- Livestock Immunology Unit, International Education and Research Centre for Food and Agricultural Immunology, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan
- Correspondence: or (A.K.M.H.K.); (H.K.); Tel.: +880-1712-164794 (A.K.M.H.K.); +81-22-757-4372 (H.K.)
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Toll-Like Receptors as Drug Targets in the Intestinal Epithelium. Handb Exp Pharmacol 2021; 276:291-314. [PMID: 34783909 DOI: 10.1007/164_2021_563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Toll-like receptors (TLRs) receptors are responsible for initiation of inflammatory responses by their recognition of molecular patterns present in invading microorganisms (such as bacteria, viruses or fungi) or in molecules released following tissue damage in disease states. Expressed in the intestinal epithelium, they initiate an intracellular signalling cascade in response to molecular patterns resulting in the activation of transcription factors and the release of cytokines, chemokines and vasoactive molecules. Intestinal epithelial cells are exposed to microorganisms on a daily basis and form part of the primary defence against pathogens by using TLRs. TLRs and their accessory molecules are subject to tight regulation in these cells so as to not overreact or react in unnecessary circumstances. TLRs have more recently been associated with chronic inflammatory diseases as a result of inappropriate regulation, this can be damaging and lead to chronic inflammatory diseases such as inflammatory bowel disease (IBD). Targeting Toll-like receptors offers a potential therapeutic approach for IBD. In this review, the current knowledge on the TLRs is reviewed along with their association with intestinal diseases. Finally, compounds that target TLRs in animal models of IBD, clinic trials and their future merit as targets are discussed.
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Effects of a Lactobacilli Probiotic on Reducing Duration of URTI and Fever, and Use of URTI-Associated Medicine: A Re-Analysis of a Randomized, Placebo-Controlled Study. Microorganisms 2021; 9:microorganisms9030528. [PMID: 33806508 PMCID: PMC7998138 DOI: 10.3390/microorganisms9030528] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 02/26/2021] [Accepted: 02/28/2021] [Indexed: 12/12/2022] Open
Abstract
We previously reported on the effects of Lactoplantibacillus plantarum DR7 on reducing Upper Respiratory Tract Infections (URTI) symptoms’ score and frequency in 109 adults upon a 12-week consumption at 109 colony-forming units (CFU)/day, but several limitations were detected in the publication. Thus, the present study re-analyzed some data with the aim to address some of these weaknesses, and presents new data on duration of URTI and consumption of URTI-associated medication, as compared to the placebo. Our re-analyses found probiotic administration significantly reduced the proportion of patient days of URTI and of fever (all p < 0.05). Recent history of URTI was a prevalent co-factor in affecting duration of URTI symptoms and fever, while other demographic and clinical factors had no influence. Exploratory analyses suggested probiotic had an earlier benefit in patients without a recent history of URTI compared to those with a recent history of URTI. Therefore, recent history of infections could have a modulatory effect on probiotic efficacy. Average number of months with reported use of URTI-related medication was 3.4-times lower in the probiotic group as compared to placebo (p = 0.016) during the intervention. Taken together, our present new data further support previous findings that DR7 probiotic had a beneficial effect on URTI.
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Lehtoranta L, Latvala S, Lehtinen MJ. Role of Probiotics in Stimulating the Immune System in Viral Respiratory Tract Infections: A Narrative Review. Nutrients 2020; 12:nu12103163. [PMID: 33081138 PMCID: PMC7602805 DOI: 10.3390/nu12103163] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 10/05/2020] [Accepted: 10/13/2020] [Indexed: 12/29/2022] Open
Abstract
Viral respiratory tract infection (RTI) is the most frequent cause of infectious illnesses including the common cold. Pharmacological solutions for treating or preventing viral RTIs are so far limited and thus several self-care products are available in the market. Some dietary supplements such as probiotics have been shown to modulate immune system function and their role in reducing the risk and the course of RTIs has been investigated extensively within the past decade. However, the mechanism of action and the efficacy of probiotics against viral RTIs remains unclear. We searched PubMed, Google Scholar, and Web of Knowledge for pre-clinical and clinical studies investigating the effect of probiotics on respiratory virus infections, immune response, and the course of upper and lower respiratory tract illness. The literature summarized in this narrative review points out that specific probiotic strains seem effective in pre-clinical models, through stimulating the immune system and inhibiting viral replication. Clinical studies indicate variable efficacy on upper respiratory illnesses and lack proof of diagnosed viral infections. However, meta-analyses of clinical studies indicate that probiotics could be beneficial in upper respiratory illnesses without specific etiology. Further studies aiming at discovering the mechanisms of action of probiotics and clinical efficacy are warranted.
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Larenas-Linnemann D, Rodríguez-Pérez N, Arias-Cruz A, Blandón-Vijil MV, Del Río-Navarro BE, Estrada-Cardona A, Gereda JE, Luna-Pech JA, Navarrete-Rodríguez EM, Onuma-Takane E, Pozo-Beltrán CF, Rojo-Gutiérrez MI. Enhancing innate immunity against virus in times of COVID-19: Trying to untangle facts from fictions. World Allergy Organ J 2020; 13:100476. [PMID: 33072240 PMCID: PMC7546230 DOI: 10.1016/j.waojou.2020.100476] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 09/24/2020] [Accepted: 09/30/2020] [Indexed: 12/14/2022] Open
Abstract
Introduction In light of the current COVID-19 pandemic, during which the world is confronted with a new, highly contagious virus that suppresses innate immunity as one of its initial virulence mechanisms, thus escaping from first-line human defense mechanisms, enhancing innate immunity seems a good preventive strategy. Methods Without the intention to write an official systematic review, but more to give an overview of possible strategies, in this review article we discuss several interventions that might stimulate innate immunity and thus our defense against (viral) respiratory tract infections. Some of these interventions can also stimulate the adaptive T- and B-cell responses, but our main focus is on the innate part of immunity. We divide the reviewed interventions into: 1) lifestyle related (exercise, >7 h sleep, forest walking, meditation/mindfulness, vitamin supplementation); 2) Non-specific immune stimulants (letting fever advance, bacterial vaccines, probiotics, dialyzable leukocyte extract, pidotimod), and 3) specific vaccines with heterologous effect (BCG vaccine, mumps-measles-rubeola vaccine, etc). Results For each of these interventions we briefly comment on their definition, possible mechanisms and evidence of clinical efficacy or lack of it, especially focusing on respiratory tract infections, viral infections, and eventually a reduced mortality in severe respiratory infections in the intensive care unit. At the end, a summary table demonstrates the best trials supporting (or not) clinical evidence. Conclusion Several interventions have some degree of evidence for enhancing the innate immune response and thus conveying possible benefit, but specific trials in COVID-19 should be conducted to support solid recommendations.
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Key Words
- ACE2, Angiotensin converting enzime-2
- APC, Antigen-presenting cell
- BCG, Bacillus Calmette-Guérin
- BV, Bacterial vaccine
- Bacillus calmette-guérin
- Bacterial vaccine
- CCL-5, Chemokine (C–C motif) ligand 5
- CI, Confidence interval
- CNS, Central nervous system
- COVID-19
- COVID-19, Coronavirus disease-2019
- CXCR3A, CXC chemokine receptor 3A
- DAMPs, Damage-associated molecular patterns
- DC, Dendritic cell
- DLE, Dialyzable leukocyte extract
- Exercise
- Gαs: G protein coupled receptor alfa-subunits, HSP
- Heat shock proteins, HLA-DR
- Immune response
- Immunoglobulin, IGFBP6
- Innate
- Insulin-like growth-factor-binding-protein 6, IL
- Intercellular adhesion molecule type 1, IFN
- Interferon, IG
- Interleukin, MBSR
- MCP-1, Monocyte chemoattractant protein-1
- MMR
- MODS, Multi-organ dysfunction syndrome
- Major histocompatibility complex class II cell surface receptor, ICAM-1
- Mindfulness
- Mindfulness-based stress reduction, mCa++: Intramitochondrial calcium
- MyD88, Myeloid differentiation primary response 88
- NF-κB, Nuclear factor kappaB
- NK, Natural killer
- NK-Cell
- NOD2, Nucleotide-binding oligomerization domain-containing protein 2
- OR, Odds ratio
- OxPhos: Oxidative phosphorylation, PAMPs
- PKC, Protein kinase C
- PPD, Purified protein derivative (tuberculin)
- PUFA, Polyunsaturated fatty acid
- Pathogen-associated molecular patterns, PBMC
- Peripheral blood mononuclear cell, PI3K/Akt: Phosphatidylinositol 3-kinase pathway
- R0: Basic reproduction number, REM
- Rapid eye movement, RIPK2
- Reactive nitrogen species, ROS
- Reactive oxygen species, SARS-CoV-2
- Receptor iteracting serine/threonine kinase 2, RNA
- Ribonucleic acid, RNS
- Severe acute respiratory syndrome coronavirus 2, SIRS
- Sleep
- Systemic inflammatory response syndrome, TCR:T-cell receptor
- TLR, Toll-like receptor
- TNF-α, Tumor necrosis factor alpha
- TRPV, Thermolabile calcium channels
- Th, T helper-cell
- Trained immunity
- URTI, Upper-respiratory tract infection
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Affiliation(s)
- Désirée Larenas-Linnemann
- Médica Sur, Clinical Foundation and Hospital, Mexico City, Mexico
- Corresponding author. Médica Sur, Fundación clínica y hospital, Puente de piedra 150, T2Toriello Guerra, Tlalpan, Ciudad de México, México, 14050, Mexico. E-mails:
| | | | - Alfredo Arias-Cruz
- State University of Nuevo León, School of Medicine and University Hospital Dr. José Eleuterio González, Monterrey, Nuevo Leon, Mexico
| | | | | | | | | | - Jorge A. Luna-Pech
- Departamento de Disciplinas Filosóficas, Metodológicas e Instrumentales (CUCS), Universidad de Guadalajara, Guadalajara, Jalisco, Mexico
| | | | - Ernesto Onuma-Takane
- Fundación Clínica y Hospital Médica Sur, Ciudad de México, México, Mexico City, Mexico
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