The function of specialized pro-resolving endogenous lipid mediators, vitamins, and other micronutrients in the control of the inflammatory processes: Possible role in patients with SARS-CoV-2 related infection.

Inflammation is an essential protective response against harmful stimuli, such as invading pathogens, damaged cells, or irritants. Physiological inflammation eliminates pathogens and promotes tissue repair and healing. Effective immune response in humans depends on a tightly regulated balance among inflammatory and anti-inflammatory mechanisms involving both innate and adaptive arms of the immune system. Excessive inflammation can become pathological and induce detrimental effects. If this process is not self-limited, an inappropriate remodeling of the tissues and organs can occur and lead to the onset of chronic degenerative diseases. A wide spectrum of infectious and non-infectious agents may activate the inflammation, via the release of mediators and cytokines by distinct subtypes of lymphocytes and macrophages. Several molecular mechanisms regulate the onset, progression, and resolution of inflammation. All these steps, even the termination of this process, are active and not passive events. In particular, a complex interplay exists between mediators (belonging to the group of Eicosanoids), which induce the beginning of inflammation, such as Prostaglandins (PGE2), Leukotrienes (LT), and thromboxane A2 (TXA2), and molecules which display a key role in counteracting this process and in promoting its proper resolution. The latter group of mediators includes: ω-6 arachidonic acid (AA)-derived metabolites, such as Lipoxins (LXs), ω -3 eicosapentaenoic acid (EPA)-derived mediators, such as E-series Resolvins (RvEs), and ω -3 docosahexaenoic (DHA)-derived mediators, such as D-series Resolvins (RvDs), Protectins (PDs) and Maresins (MaRs). Overall, these mediators are defined as specialized pro-resolving mediators (SPMs). Reduced synthesis of these molecules may lead to uncontrolled inflammation with possible harmful effects. ω-3 fatty acids are widely used in clinical practice as rather inexpensive, safe, readily available supplemental therapy. Taking advantage of this evidence, several researchers are suggesting that SPMs may have beneficial effects in the complementary treatment of patients with severe forms of SARS-CoV-2 related infection, to counteract the "cytokine storm" observed in these individuals. Well-designed and sized trials in patients suffering from COVID-19 with different degrees of severity are needed to investigate the real impact in the clinical practice of this promising therapeutic approach.

COVID-19, what could sepsis, severe acute pancreatitis, gender differences, and aging teach us?

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a potentially life-threatening disease, defined as Coronavirus Disease 19 (COVID-19). The most common signs and symptoms of this pathological condition include cough, fever, shortness of breath, and sudden onset of anosmia, ageusia, or dysgeusia. The course of COVID-19 is mild or moderate in more than 80% of cases, but it is severe or critical in about 14% and 5% of infected subjects respectively, with a significant risk of mortality. SARS-CoV-2 related infection is characterized by some pathogenetic events, resembling those detectable in other pathological conditions, such as sepsis and severe acute pancreatitis. All these syndromes are characterized by some similar features, including the coexistence of an exuberant inflammatory- as well as an anti-inflammatory-response with immune depression. Based on current knowledge concerning the onset and the development of acute pancreatitis and sepsis, we have considered these syndromes as a very interesting paradigm for improving our understanding of pathogenetic events detectable in patients with COVID-19. The aim of our review is: 1)to examine the pathogenetic mechanisms acting during the emergence of inflammatory and anti-inflammatory processes in human pathology; 2)to examine inflammatory and anti-inflammatory events in sepsis, acute pancreatitis, and SARS-CoV-2 infection and clinical manifestations detectable in patients suffering from these syndromes also according to the age and gender of these individuals; as well as to analyze the possible common and different features among these pathological conditions; 3)to obtain insights into our knowledge concerning COVID-19 pathogenesis. This approach may improve the management of patients suffering from this disease and it may suggest more effective diagnostic approaches and schedules of therapy, depending on the different phases and/or on the severity of SARS-CoV-2 infection.

Tensegrity model hypothesis: may this paradigm be useful to explain hepatic and pancreatic carcinogenesis in patients with persistent hepatitis B or hepatitis C virus infection?

CONTEXT: Hepatitis B (HBV) and hepatitis C virus (HCV) possess well-known oncogenic properties and may promote carcinogenesis in liver. However antigens and replicative sequences of HBV/HCV have been also detected in different extra-hepatic tissues, including the pancreas. Although epidemiological studies and meta-analyses have recently suggested that HBV/HCV may be also risk factors for pancreatic cancer and several researches have investigated the possible mechanisms and intra-/extra-cellular paths involved in pancreatic and hepatic carcinogenesis, to date, these complex processes remain largely unexplained. OBJECTIVES: In our paper, we aimed to propose a comprehensive and qualitative hypothetical model, describing how HBV/HCV may exert their oncogenic role. METHODS: We performed a systematic research of scientific literature, by searching MEDLINE, the Cochrane Library and EMBASE databases. The used keywords were: "chronic HBV/HCV", "pancreatic cancer", "liver carcinoma", "carcinogenesis mechanisms", "tensional integrity", "cytoskeleton", and "extracellular matrix". RESULTS: Taking advantage from available studies, we suggest an unifying hypothesis based on results and data, obtained from different areas of research. In particular we considered the well-defined model of tensional integrity and correlated it to changes induced by HBV/HCV in viscoelastic properties/stiffness of cellular/extracellular microenvironments. These events perturb the tightly-regulated feedback loop, which usually couples the intracellular-generated forces to substrate rigidity of extracellular compartments. Therefore, such a change strongly affects intracellular functions and cellular fate, by promoting a substantial deregulation of critical intracellular biochemical activities and genome expression. CONCLUSIONS: Our hypothesis might provide for the first time a reliable system, which correlates tensional integrity model with intra-/extra-cellular modifications, occurring in liver and pancreas during HBV/HCV-induced carcinogenesis. This approach might improve our understanding of pathogenetic mechanisms involved in the development of pancreatic and hepatic carcinogenesis , enhancing the possibility of their treatment. Furthermore, should the usefulness of this model be definitively confirmed, it might be also helpful to extend its field of application to other viruses-related cancers.