Gut microbiota in a population highly affected by obesity and type 2 diabetes and susceptibility to COVID-19

Coronavirus disease 2019(COVID-19)is a disease produced by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)and it is currently causing a catastrophic pandemic affecting humans worldwide.This disease has been lethal for approximately 3.12 million people around the world since January 2020.Globally,among the most affected countries,Mexico ranks third in deaths after the United States of America and Brazil.Although the high number of deceased people might also be explained by social aspects and lifestyle customs in Mexico,there is a relationship between this high proportion of deaths and comorbidities such as high blood pressure(HBP),type 2 diabetes,obesity,and metabolic syndrome.The official epidemiological figures reported by the Mexican government have indicated that 18.4%of the population suffers from HBP,close to 10.3%of adults suffer from type 2 diabetes,and approximately 36.1%of the population suffers from obesity.Disbalances in the gut microbiota(GM)have been associated with these diseases and with COVID-19 severity,presumably due to inflammatory dysfunction.Recent data about the association between GM dysbiosis and metabolic diseases could suggest that the high levels of susceptibility to SARSCoV-2 infection and COVID-19 morbidity in the Mexican population are primarily due to the prevalence of type 2 diabetes,obesity,and metabolic syndrome.

Study of tree shrew biology and models: A booming and prosperous field for biomedical research

The tree shrew(Tupaia belangeri)has long been proposed as a suitable alternative to non-human primates(NHPs)in biomedical and laboratory research due to its close evolutionary relationship with primates.In recent years,significant advances have facilitated tree shrew studies,including the determination of the tree shrew genome,genetic manipulation using spermatogonial stem cells,viral vector-mediated gene delivery,and mapping of the tree shrew brain atlas.However,the limited availability of tree shrews globally remains a substantial challenge in the field.Additionally,determining the key questions best answered using tree shrews constitutes another difficulty.Tree shrew models have historically been used to study hepatitis B virus(HBV)and hepatitis C virus(HCV)infection,myopia,and psychosocial stress-induced depression,with more recent studies focusing on developing animal models for infectious and neurodegenerative diseases.Despite these efforts,the impact of tree shrew models has not yet matched that of rodent or NHP models in biomedical research.This review summarizes the prominent advancements in tree shrew research and reflects on the key biological questions addressed using this model.We emphasize that intensive dedication and robust international collaboration are essential for achieving breakthroughs in tree shrew studies.The use of tree shrews as a unique resource is expected to gain considerable attention with the application of advanced techniques and the development of viable animal models,meeting the increasing demands of life science and biomedical research.