Working Paper
ARTICLE
Subject:
Medicine And Pharmacology,
Pathology And Pathobiology
Keywords:
Inflammation; Cytokine Storm; ⍵-3; ⍵-6; SPMs; Resolvins
Online: 30 August 2020 (16:47:53 CEST)
Inflammation is an essential protective response against injury or infection. Physiological inflammation eliminates the pathogen, promotes tissue repair and healing. An exaggerated, out of control inflammation, however, can become pathological. Inflammation can generate secondary cell damage, inflame the vessels (endothelitis), activate coagulation processes. Among these pathogenetic factors (cell damage, inflammation, endothelitis, coagulopathies), self-amplification mechanisms can be created, spreading beyond the initial site, up to Multiple Organ Failure (MOF) and host death. If the inflammation does not resolve in a physiological way, the remodeling of the tissues can be maladaptive and lead to the onset of chronic inflammatory degenerative diseases. Diseases such as sepsis, burns, polytrauma, severe forms of influenza or COVID-19, are characterized by a condition of hyperinflammation, associated with a condition of immunosuppression. The initial events triggered by the pathogen (cell damage, interferon response in the case of viruses) ignite the inflammation by activating the inflammasome, the transcription factor NFkB, the release of pro-inflammatory eicosanoids (Prostaglandins, Leukotrienes, Thromboxanes) by neutrophils and macrophages. Hence, the cells of the innate immune system produce pro-inflammatory cytokines. Indeed, the ‘’eicosanoid storm’’ precedes the ‘’cytokine storm’’. Eicosanoids are a group of potent endogenous lipid mediators derived from omega-6 fatty acids Arachidonic Acid (AA). Eicosanoids include a group of molecules with pro-inflammatory (Prostaglandins, Leukotriens) and pro-coagulant (Thromboxanes) action. In addition, Arachidonic Acid (AA) is the source of Lipoxins (LXs). Lipoxins belong to a group of molecules collectively referred to as specialized pro-solving mediators (SPMs) which also include molecules derived from w-3 eicosapentaenoic acid (EPA): Resolvins (ReV-E sieres) and w-3 docohexanoic (DHA): Resolvins D-series (ReV D-series); Protectins (PTs); Maresins (MaRs). SPMs are important for the resolution phase of inflammation to take place properly. Their deficiency could be involved in both acute uncontrolled inflammation and chronic inflammation. The active regulation of the acute inflammatory process, integrating the precursors of Specialized Pro-resolving Mediators (SPMs), such as ⍵-6 and ⍵-3 in balanced ratio, or the SPMs themselves, could be a complementary therapeutic approach useful for taming the "storm of cytokines '' which characterizes exaggerated forms of inflammation. ⍵-3 and ⍵-6 are part of already widely used, readily available, inexpensive and safe supplements. Resolvins have already been included in clinical trials for various other inflammatory diseases (eye diseases, periodontal diseases).
Working Paper
ARTICLE
Subject:
Medicine And Pharmacology,
Pathology And Pathobiology
Keywords:
COVID-19; SARS CoV-2; IFN-⍺; IFN-β; IFN-λ
Online: 2 August 2020 (11:31:40 CEST)
COVID-19 disease, caused by the SARS-CoV2 virus, is a potentially fatal disease that represents a serious public health and economic problem worldwide. The SARS-CoV2 virus infects the lower respiratory tract and can cause pneumonia in humans. ARDS is the leading cause of death in COVID-19 disease. One of the main characteristics of ARDS is the cytokine storm, an uncontrolled systemic inflammatory response resulting from the release of pro-inflammatory cytokines and chemokines and growth factors, by immune cells. The other important aspect of the disease is represented by the involvement of the vascular organ that undergoes endothelitis. Hyperinflammation and endothelitis contribute in various ways to trigger coagulation disorders with diffuse micro thrombotic and thromboembolic phenomena. Lastly, multiple organ failure may occur (MOF). Since so far there is no approved treatment, there is an urgent need to reposition known treatments, considered safe, to be included in trials. Naturally produced interferons represent the body's first line of defense against viruses. Pharmacological forms, obtained by means of genetic recombination techniques, have long been approved and used to treat numerous pathologies. Interferons are divided into three families, within which some subfamilies are distinguishable. Only IFN-II comprises a single isoform which has completely different aspects and functions. The IFN I and III, however, each comprise different subfamilies (17 subfamilies the IFN-I and 4 subfamilies the IFN-III), share many aspects, representing the body's first antiviral response, but play different roles. The use of IFNs has been studied in two severe hCoV (Human Coronavirus) diseases, closely related to COVID-19 disease, such as SARS and MERS. Numerous in vitro and in vivo studies have been conducted, often in combination with other antivirals. The results have been controversial. The positive results in vitro and in experimental animals were often not replicable in humans. The possible positioning of these molecules in the right window of therapeutic opportunity requires that the complex dialogue between IFN, inflammasome, cytokines, pro-inflammatory chemokines, growth factors and barrier function be shed light.
Working Paper
ARTICLE
Subject:
Medicine And Pharmacology,
Pathology And Pathobiology
Keywords:
COVID-19; Inflammasome; Interleukin 1β; Inflammation; Innate Immune System
Online: 12 July 2020 (08:17:56 CEST)
Covid-19 disease is caused by SARS Cov-2 virus. Despite its high transmissibility, the CFR (Case Fatality Rate) of COVID-19 seems to be lower than the SARS (9,5%) and MERS (34,4%) ones93 , but higher than the influenza one (0-1%)94,95 . The disease is asymptomatic or paucisymptomatic in most of the patients, although in few cases it can be characterized by serious complications. The main causes of hospitalization in intensive care are represented by ALI (Acute Lung Injury), ARDS (Acute Respiratory Distress Syndrome), cardiovascular problems and coagulopathies (diffuse thrombosis, microthrombosis, embolisms, myocarditis, arrhytmias, heart failure, stroke)96-98, acute nephropathy99,100 and encephalopathies101. The virus presence in the vascular wall can cause endotheliitis, which triggers the process of diffuse coagulation that can lead to a worsening of the systemic inflammation. The exaggerated inflammatory response seems to be connected with the development of ARDS, MOF (Multiple Organ Failure) and coagulopathies102-107.