Revisiting Pleiotropic Effects of Type I Interferons: Rationale for Its Prophylactic and Therapeutic Use Against SARS-CoV-2.

The pandemic distribution of SARS-CoV-2 together with its particular feature of inactivating the interferon-based endogenous response and accordingly, impairing the innate immunity, has become a challenge for the international scientific and medical community. Fortunately, recombinant interferons as therapeutic products have accumulated a long history of beneficial therapeutic results in the treatment of chronic and acute viral diseases and also in the therapy of some types of cancer. One of the first antiviral treatments during the onset of COVID-19 in China was based on the use of recombinant interferon alfa 2b, so many clinicians began to use it, not only as therapy but also as a prophylactic approach, mainly in medical personnel. At the same time, basic research on interferons provided new insights that have contributed to a much better understanding of how treatment with interferons, initially considered as antivirals, actually has a much broader pharmacological scope. In this review, we briefly describe interferons, how they are induced in the event of a viral infection, and how they elicit signaling after contact with their specific receptor on target cells. Additionally, some of the genes stimulated by type I interferons are described, as well as the way interferon-mediated signaling is torpedoed by coronaviruses and in particular by SARS-CoV-2. Angiotensin converting enzyme 2 (ACE2) gene is one of the interferon response genes. Although for many scientists this fact could result in an adverse effect of interferon treatment in COVID-19 patients, ACE2 expression contributes to the balance of the renin-angiotensin system, which is greatly affected by SARS-CoV-2 in its internalization into the cell. This manuscript also includes the relationship between type I interferons and neutrophils, NETosis, and interleukin 17. Finally, under the subtitle of "take-home messages", we discuss the rationale behind a timely treatment with interferons in the context of COVID-19 is emphasized.

Chronic comorbidities and clinical outcomes in patients with and without COVID-19: a large population-based study using national administrative healthcare open data of Mexico.

Coronavirus disease 2019 (COVID-19) was rapidly expanded worldwide within a short period. Its relationship with chronic comorbidities is still unclear. We aimed to determine the effects of chronic comorbidities on clinical outcomes of patients with and without COVID-19. This was an analysis of 65,535 patients with suspicion of viral respiratory disease (38,324 SARS-CoV-2 positive and 27,211 SARS-CoV-2 negative) from January 01 to May 12, 2020 using the national administrative healthcare open data of Mexico. SARS-CoV-2 infection was confirmed by reverse-transcriptase-polymerase-chain-reaction. General characteristics and chronic comorbidities were explored. Clinical outcomes of interest were hospital admission, pneumonia, intensive care unit admission, endotracheal intubation and mortality. Prevalence of chronic comorbidities was 49.4%. Multivariate logistic regression analysis showed that the effect of age, male sex, bronchial asthma, diabetes mellitus and chronic kidney disease on clinical outcomes was similar for both SARS-CoV-2 positive and negative patients. Adverse clinical outcomes were associated with the time from symptoms onset to medical contact, chronic obstructive pulmonary disease, hypertension and obesity in SARS-CoV-2 positive patients, but with cardiovascular disease in SARS-CoV-2 negative patients (p value < 0.01 for all comparisons). Chronic comorbidities are commonly found in patients with suspicion of viral respiratory disease. The knowledge of the impact of comorbidities on adverse clinical outcomes can better define those COVID-19 patients at higher risk. The different impact of the specific type of chronic comorbidity on clinical outcomes in patients with and without SARS-CoV-2 infection requires further researches. These findings need confirmation using other data sources.

Assessment of dose-effect and therapeutic time window in preclinical studies of rhEGF and GHRP-6 coadministration for stroke therapy.

BACKGROUND: Stroke continues to be a leading cause of mortality and morbidity worldwide, and novel therapeutic options for ischaemic stroke are urgently needed. In this context, drug combination therapies seem to be a viable approach, which has not been fully explored in preclinical studies. OBJECTIVES: In this work, we assessed the dose-response relationship and therapeutic time window, in global brain ischaemia, of a combined therapeutic approach of recombinant human epidermal growth factor (EGF) and growth hormone-releasing peptide-6 (GHRP-6). METHODS: Mongolian gerbils underwent 15 minutes occlusion of both common carotid arteries. Four different doses of rhEGF, GHRP-6 and these combined agents were intraperitoneally administered immediately after the onset of reperfusion. Having identified a better response with both agents, rhEGF+GHRP-6 were administered at 2, 4, 6, 8 or 24 hours after the onset of reperfusion to assess the time window of effectiveness. Animals were evaluated daily for neurological deficits. Three days post-occlusion, the animals were sacrificed and 2,3,5-triphenyltetrazolium chloride was used to quantify infarcted tissues. RESULTS: The coadministration of rhEGF and GHRP-6 at doses of 100 and 600 µg/kg, respectively, administered up to 4 hours following the ischaemic insult, significantly improved survival and neurological outcome, and reduced infarct volume compared with vehicle treatment. These results are considered as an additional proof of concept as supporting a combined therapeutic approach and justify the further development of this preclinical research.

Use of growth-hormone-releasing peptide-6 (GHRP-6) for the prevention of multiple organ failure.

Novel therapies for the treatment of MOF (multiple organ failure) are required. In the present study, we examined the effect of synthetic GHRP-6 (growth hormone-releasing peptide-6) on cell migration and proliferation using rat intestinal epithelial (IEC-6) and human colonic cancer (HT29) cells as in vitro models of injury. In addition, we examined its efficacy when given alone and in combination with the potent protective factor EGF (epidermal growth factor) in an in vivo model of MOF (using two hepatic vessel ischaemia/reperfusion protocols; 45 min of ischaemia and 45 min of reperfusion or 90 min of ischaemia and 120 min of reperfusion). In vitro studies showed that GHRP-6 directly influenced gut epithelial function as its addition caused a 3-fold increase in the rate of cell migration of IEC-6 and HT29 cells (P<0.01), but did not increase proliferation ([3H]thymidine incorporation). In vivo studies showed that, compared with baseline values, ischaemia/reperfusion caused marked hepatic and intestinal damage (histological scoring), neutrophilic infiltration (myeloperoxidase assay; 5-fold increase) and lipid peroxidation (malondialdehyde assay; 4-fold increase). Pre-treatment with GHRP-6 (120 microg/kg of body weight, intraperitoneally) alone truncated these effects by 50-85% (all P<0.05) and an additional benefit was seen when GHRP-6 was used in combination with EGF (1 mg/kg of body weight, intraperitoneally). Lung and renal injuries were also reduced by these pre-treatments. In conclusion, administration of GHRP-6, given alone or in combination with EGF to enhance its effects, may provide a novel simple approach for the prevention and treatment of MOF and other injuries of the gastrointestinal tract. In view of these findings, further studies appear justified.