Intermittent fasting, a possible priming tool for host defense against SARS-CoV-2 infection: crosstalk among calorie restriction, autophagy and immune response

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is the causative pathogen of deadly Coronavirus disease-19 (COVID-19) pandemic, which emerged as a major threat to public health across the world. Although there is no clear gender or socioeconomic discrimination in the incidence of COVID-19, individuals who are older adults and/or with comorbidities and compromised immunity have a relatively higher risk of contracting this disease. Since no specific drug has yet been discovered, strengthening immunity along with maintaining a healthy living is the best way to survive this disease. As a healthy practice, calorie restriction in the form of intermittent fasting in several clinical settings has been reported to promote several health benefits, including priming of the immune response. This dietary practice also activates autophagy, a cell surveillance system that boosts up immunity. With these prevailing significance in priming host defense, intermittent fasting could be a potential strategy amid this outbreak to fighting off SARS-CoV-2 infection. Currently, no review so far available proposing intermittent fasting as an encouraging strategy in the prevention of COVID-19. A comprehensive review has therefore been planned to highlight the beneficial role of fasting in immunity and autophagy, that underlie the possible defense against SARS-CoV-2 infection. The COVID-19 pathogenesis and its impact on host immune response have also been briefly outlined. This review aimed at revisiting the immunomodulatory potential of intermittent fasting that may constitute a promising preventive strategy against COVID-19.

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Intermittent fasting, a possible priming tool for host defense against SARS-CoV-2 infection: Crosstalk among calorie restriction, autophagy and immune response

Immunology Letters ◽

10.1016/j.imlet.2020.07.001 ◽

2020 ◽

Vol 226 ◽

pp. 38-45 ◽

Cited By ~ 8

Author(s):

Md. Abdul Hannan ◽

Md. Ataur Rahman ◽

Md Saidur Rahman ◽

Abdullah Al Mamun Sohag ◽

Raju Dash ◽

...

Keyword(s):

Immune Response ◽

Host Defense ◽

Calorie Restriction ◽

Intermittent Fasting

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Toll-like receptor 9 inhibition reduces mortality in polymicrobial sepsis

Journal of Experimental Medicine ◽

10.1084/jem.20080162 ◽

2008 ◽

Vol 205 (6) ◽

pp. 1277-1283 ◽

Cited By ~ 86

Author(s):

George Plitas ◽

Bryan M. Burt ◽

Hoang M. Nguyen ◽

Zubin M. Bamboat ◽

Ronald P. DeMatteo

Keyword(s):

Immune Response ◽

Critical Role ◽

Cecal Ligation ◽

High Rate ◽

Microbial Pathogens ◽

Lower Serum ◽

Human Sepsis ◽

Cytokine Levels ◽

Potential Strategy

The high rate of mortality in patients with sepsis results from an inappropriately amplified systemic inflammatory response to infection. Toll-like receptors (TLRs) are important for the activation of innate immunity against microbial pathogens. We demonstrate a critical role of TLR9 in the dysregulated immune response and death associated with sepsis. Compared with wild-type (WT) mice, TLR9−/− mice exhibited lower serum inflammatory cytokine levels, higher bacterial clearance, and greater survival after experimental peritonitis induced by cecal ligation and puncture (CLP). Protection of TLR9−/− mice after CLP was associated with a greater number of peritoneal dendritic cells (DCs) and granulocytes than in WT controls. Adoptive transfer of TLR9−/− DCs was sufficient to protect WT mice from CLP and increased the influx of peritoneal granulocytes. Subsequent experiments with a depleting antibody revealed that granulocytes were required for survival in TLR9−/− mice. Remarkably, a single injection of an inhibitory CpG sequence that blocks TLR9 protected WT mice, even when administered as late as 12 h after CLP. Our findings demonstrate that the detrimental immune response to bacterial sepsis occurs via TLR9 stimulation. TLR9 blockade is a potential strategy for the treatment of human sepsis.

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ROLE OF HOST DEFENSE PEPTIDES OF THE INNATE IMMUNE RESPONSE IN SEPSIS

Shock ◽

10.1097/shk.0b013e318160de11 ◽

2007 ◽

pp. 1 ◽

Cited By ~ 3

Author(s):

Tobias Hirsch ◽

Marie Metzig ◽

Andreas Niederbichler ◽

Hans-Ulrich Steinau ◽

Elof Eriksson ◽

...

Keyword(s):

Immune Response ◽

Innate Immune Response ◽

Host Defense ◽

Innate Immune ◽

Host Defense Peptides ◽

Defense Peptides

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Platelets Are Critical Key Players in Sepsis

International Journal of Molecular Sciences ◽

10.3390/ijms20143494 ◽

2019 ◽

Vol 20 (14) ◽

pp. 3494 ◽

Cited By ~ 14

Author(s):

Fanny Vardon-Bounes ◽

Stéphanie Ruiz ◽

Marie-Pierre Gratacap ◽

Cédric Garcia ◽

Bernard Payrastre ◽

...

Keyword(s):

Immune Response ◽

Endothelial Cells ◽

Inflammatory Response ◽

Host Defense ◽

Critical Role ◽

Therapeutic Implications ◽

Key Players

Host defense against infection is based on two crucial mechanisms: the inflammatory response and the activation of coagulation. Platelets are involved in both hemostasis and immune response. These mechanisms work together in a complex and synchronous manner making the contribution of platelets of major importance in sepsis. This is a summary of the pathophysiology of sepsis-induced thrombocytopenia, microvascular consequences, platelet-endothelial cells and platelet–pathogens interactions. The critical role of platelets during sepsis and the therapeutic implications are also reviewed.

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The Effectiveness of Probiotics in the Treatment of Inflammatory Bowel Disease (IBD)—A Critical Review

Nutrients ◽

10.3390/nu12071973 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1973

Author(s):

Dominika Jakubczyk ◽

Katarzyna Leszczyńska ◽

Sabina Górska

Keyword(s):

Ulcerative Colitis ◽

Inflammatory Bowel Disease ◽

Immune Response ◽

Bowel Disease ◽

Genetic Background ◽

Inflammatory State ◽

Inflammatory Bowel ◽

Potential Strategy ◽

Different Strains

Inflammatory bowel disease (IBD), which affects millions of people worldwide, includes two separate diseases: Crohn’s disease (CD) and ulcerative colitis (UC). Although the background (chronic inflammatory state) and some of the symptoms of CD and UC are similar, both diseases differ from each other. It is becoming clear that a combination of many factors, in particular genetic background, host immune response and microbial reduced diversity status are associated with IBD. One potential strategy to prevent/treat IBD is gut modulation by probiotics. Over the last twenty years, many publications have focused on the role of probiotics in the course of IBD. The review discusses the utility of different strains of probiotics, especially Bifidobacterium spp., in all factors potentially involved in the etiology of IBD. The probiotic modulatory properties among different study models (cell lines, animal models of colitis, clinical study) are discussed and probiotic usefulness is assessed in relation to the treatment, prevention, and remission of diseases.

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The role of host miRNAs on Mycobacterium tuberculosis

ExRNA ◽

10.1186/s41544-019-0040-y ◽

2019 ◽

Vol 1 (1) ◽

Cited By ~ 2

Author(s):

Ava Behrouzi ◽

Marjan Alimohammadi ◽

Amir Hossein Nafari ◽

Mohammad Hadi Yousefi ◽

Farhad Riazi Rad ◽

...

Keyword(s):

Immune Response ◽

Mycobacterium Tuberculosis ◽

Innate Immune Response ◽

Host Defense ◽

Pathogenic Bacteria ◽

Biological Pathways ◽

Innate Immune ◽

The Other ◽

Non Coding Rnas

Abstract MicroRNAs are non-coding RNAs, playing an important role in regulating many biological pathways, such as innate immune response against various infections. Different studies confirm that many miRNAs act as important regulators in developing a strategy for the survival of Mycobacterium tuberculosis in the host cell. On the other hand, an innate immune response is one of the important aspects of host defense against Mycobacterium. Considering the importance of miRNAs during tuberculosis infection, we focused on studies that performed on the role of various miRNAs related to pathogenic bacteria, M. tuberculosis in the host. Also, we have introduced important miRNAs that can be used as a biomarker for the detection of Mycobacterium.

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Research progress on immune response of B lymphocytes and anti-Mycobacterium tuberculosis infection

Infection International ◽

10.1515/ii-2017-0120 ◽

2016 ◽

Vol 5 (1) ◽

pp. 1-4

Author(s):

Jiacong You

Keyword(s):

Immune Response ◽

Mycobacterium Tuberculosis ◽

B Lymphocytes ◽

Host Defense ◽

Humoral Immunity ◽

Cellular Immunity ◽

Research Progress ◽

Mycobacterium Tuberculosis Infection ◽

Cellular Immune

Abstract Multiple studies elucidated the importance of cellular immune mechanisms for protection against Mycobacterium tuberculosis. However, recent studies showed that B lymphocytes play a role that is underestimated through various interactions with cellular immune response, forming an important aspect of host defense against M. tuberculosis bacteria. Therefore, the author hereby proposes a progressive perspective for immunology of tuberculosis, i.e., cellular immunity and humoral immunity are not necessarily mutually exclusive. The present study summarizes recent studies that support the important role of B lymphocytes in terms of M. tuberculosis infection.

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Role of Bacterial Lipopolysaccharide in Enhancing Host Immune Response toCandida albicans

Clinical and Developmental Immunology ◽

10.1155/2013/320168 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 17

Author(s):

Helen Rogers ◽

David W. Williams ◽

Gui-Jie Feng ◽

Michael A. O. Lewis ◽

Xiao-Qing Wei

Keyword(s):

Immune Response ◽

Human Peripheral Blood ◽

Cell Receptor ◽

Bacterial Lipopolysaccharide ◽

Dependent Manner ◽

Blood Monocytes ◽

Gm Csf ◽

A Cell ◽

Human Infections

Human infections involving yeast of the genusCandidaoften occur in the presence of bacteria, and, as such, it is important to understand how these bacteria influence innate host immunity towardsCandida. Dectin-1 is a cell receptor of macrophages forCandida albicansrecognition. The aim of this study was to examine dectin-1 expression by monocytes after stimulation with bacterial lipopolysaccharide (LPS), followed by heat-killedC. albicans(HKC). Freshly isolated human peripheral blood monocytes (PBMCs) and human monocytes cell line (THP-1) cells expressed low levels of dectin-1. Stimulation with LPS and GM-CSF/IL-4 was found to increase dectin-1 expression in both CD14+human PBMC and THP-1 cells. Enhanced dectin-1 expression resulted in increased phagocytosis ofCandida. When THP-1 cells were challenged only with HKC, detectable levels of IL-23 were not evident. However, challenge by LPS followed by varying concentrations of HKC resulted in increased IL-23 expression by THP-1 cells in HKC dose-dependent manner. Increased expression of IL-17 by PBMC also occurred after stimulation withCandidaand LPS. In conclusion, bacterial LPS induces an enhanced immune response toCandidaby immune cells, and this occurs through increasing dectin-1 expression.

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Role of Dendritic Cells and Alveolar Macrophages in Regulating Early Host Defense against Pulmonary Infection with Cryptococcus neoformans

Infection and Immunity ◽

10.1128/iai.00454-09 ◽

2009 ◽

Vol 77 (9) ◽

pp. 3749-3758 ◽

Cited By ~ 73

Author(s):

John J. Osterholzer ◽

Jami E. Milam ◽

Gwo-Hsiao Chen ◽

Galen B. Toews ◽

Gary B. Huffnagle ◽

...

Keyword(s):

Immune Response ◽

Dendritic Cells ◽

Cryptococcus Neoformans ◽

Innate Immune Response ◽

Host Defense ◽

Alveolar Macrophages ◽

Pulmonary Infection ◽

Innate Immune ◽

Cellular Mechanisms

ABSTRACT Successful pulmonary clearance of the encapsulated yeast Cryptococcus neoformans requires a T1 adaptive immune response. This response takes up to 3 weeks to fully develop. The role of the initial, innate immune response against the organism is uncertain. In this study, an established model of diphtheria toxin-mediated depletion of resident pulmonary dendritic cells (DC) and alveolar macrophages (AM) was used to assess the contribution of these cells to the initial host response against cryptococcal infection. The results demonstrate that depletion of DC and AM one day prior to infection results in rapid clinical deterioration and death of mice within 6 days postinfection; this effect was not observed in infected groups of control mice not depleted of DC and AM. Depletion did not alter the microbial burden or total leukocyte recruitment in the lung. Mortality (in mice depleted of DC and AM) was associated with increased neutrophil and B-cell accumulation accompanied by histopathologic evidence of suppurative neutrophilic bronchopneumonia, cyst formation, and alveolar damage. Collectively, these data define an important role for DC and AM in regulating the initial innate immune response following pulmonary infection with C. neoformans. These findings provide important insight into the cellular mechanisms which coordinate early host defense against an invasive fungal pathogen in the lung.

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Role of Dendritic Cells in Pathogen Infections: A Current Perspective

10.5772/intechopen.95551 ◽

2021 ◽

Author(s):

José Luis Muñoz-Carrillo ◽

Juan Francisco Contreras-Cordero ◽

Oscar Gutiérrez-Coronado ◽

Paola Trinidad Villalobos-Gutiérrez ◽

Luis Guillermo Ramos-Gracia ◽

...

Keyword(s):

Immune Response ◽

Dendritic Cells ◽

Adaptive Immunity ◽

Host Defense ◽

Phagocytic Activity ◽

Innate And Adaptive Immunity ◽

Current Perspective ◽

Bacteria And Fungi ◽

A Current

Dendritic cells (DC) represent an important link between innate and adaptive immunity, which play an important role during the immune response against pathogens. There are several populations and subpopulations of DC, but mainly two subpopulations are characterized: the classic DC specialized in the processing and presentation of the antigen; and the plasmacytoid DC that have a high phagocytic activity and capacity for the production of cytokines. This chapter aims to present the current aspects related to the most relevant characteristics and functions of DC, as well as their role in host defense against infections by viruses, parasites, bacteria, and fungi.

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