A scientific perspective of how and why Omicron is less severe than SARS-CoV-2

Omicron is currently the dominant variant of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the coronavirus responsible for the coronavirus disease 2019(COVID-19)pandemic.Omicron is associated with mild symptoms,although it can cause harmful effects in high-risk patient populations.Omicron and COVID-19 affect multiple organ systems,including the respiratory system,gastrointestinal tract,cardiovascular system,central nervous system,ophthalmic system,genitourinary tract,and musculoskeletal system.COVID-19 infects additional organ systems,including the hematological system,hepatobiliary system,renal system,and dermatologic system.The viral-induced complications were compared to discuss the effects of Omicron versus the authentic SARS-CoV-2 virus,revealing less detrimental outcomes for Omicron.Moreover,COVID-19 is more likely to infect older adults,males,and obesity with mild to severe symptoms.Omicron causes mild symptoms in younger populations and overweight females.Data were acquired using PubMed,Centers for Disease Prevention and Control,and the World Health Organization.COVID-19 and Omicron mechanisms causing organ system-related complications are likely because of the natural immune response to the active infection,the uncontrollable release of cytokines causing cytokine release syndrome,and direct viral damage through angiotensin-converting enzyme 2/transmembrane serine protease 2 receptor binding and entrance to the host cell for infection.

A clinically relevant combination treatment with doxorubicin and cyclophosphamide does not induce hepatotoxicity in C57BL/6J mice

Background and aims:Chronic exposure to chemotherapeutics can lead to severe adverse events including hepatotoxicity.A combination chemotherapy regimen of doxorubicin(DOX)and cyclophos-phamide(CPS)is employed in treatment of several cancers such as leukemia,lymphoma,and breast cancer.It is not well understood whether a combination therapy with DOX and CPS can induce hepa-totoxicity.We therefore sought to determine whether co-administration of DOX and CPS at their clini-cally relevant doses and frequency results in hepatotoxicity.Methods:Male C57BL/6J mice received one intraperitoneal injection of saline or DOX-2 mg/kg and CPS-50 mg/kg once a week for 4 weeks.After the treatment period,liver histology and various serum bio-markers of hepatotoxicity were assessed.Results:Co-treatment with DOX and CPS did not alter the serum levels of alanine aminotransferase(ALT),alkaline phosphatase(ALP),bilirubin,albumin,globulin,or total protein.Similarly,co-administration of DOX and CPS did not result in a noticeable change in liver histology.However,it was notable that the concomitant treatment with DOX and CPS resulted in a significant increase in serum levels of aspartate aminotransferase(AST).Elevated serum AST levels were also associated with increased serum creatinine kinase(CK)levels,suggesting that the elevated serum AST levels are likely due to muscle injury following the co-administration of DOX and CPS.Conclusions:Taken together,our results,for the first time,suggest that co-administration of DOX and CPS,at their clinically relevant doses and frequency does not induce a significant hepatotoxicity in the mice.

COVID-19 induced renal injury differs from that in other viral-infections

Background:Kidney injuries caused by several viral diseases have been reported worldwide among all age groups,races,and genders.Of particular importance is coronavirus disease 2019(COVID-19),and its prevalence in communities infecting all patient populations with symptoms ranging from asymptomatic to severe,including complications and mortality.Methods:Data were acquired from PubMed,Scopus,Google Scholar,Centers for Disease Prevention and Control(CDC),and Lexi-Comp using the following search terms:“COVID-19 and renal pathology,”“COVID-19 induced kidney disease,”“Viral infection induced kidney disease,”and“Viral infection induced renal damage.”Titles and abstracts were manually analyzed as per the exclusion and inclusion criteria of relevant articles;relevance of articles included studies on the pathology of a specific viral infection and the impact of the virus on the adult renal system.Results:The mechanisms for renal disease due to COVID-19 include direct renal tubular injury,cytokine storm,inflammation,thrombosis vs.acute tubular necrosis,thrombotic events,and direct renal injury.Although some mechanisms behind renal dysfunction among the studied viral infections are similar,the prevalence rates of kidney injury or damage differ.This might be described by recommended prophylactic and therapeutic approaches that can alter the viral infection characteristics and possibly the impact a particular organ system.Conclusion:The patient population at risk was old in age and had a high body mass index.The mechanisms associated with renal dysfunction are similar,including direct renal injury through angiotensin converting enzyme 2(ACE2)entry,inflammation,and thrombosis.The renal pathology of coronaviruses that differs from that of other prevalent viral infections is the activation of cytokine storm,which causes elevations of a greater number and different kinds of cytokines than other viral infections.