Renin Angiotensin System, Gut-Lung Cross Talk and Microbiota. Lessons from SARS-CoV Infections

The two antagonistic systems of angiotensin converting enzyme (ACE)-1 and ACE-2 are in the “eye of the hurricane” of severe acute respiratory syndrome coronavirus (SARS-CoV-2). The receptor of the SARS-CoV-2 is the same as ACE-2, which causes its under-expression after binding it, followed by the internalization of the complex virus-ACE-2. ACE-2 have multiple functions with specially relevance in cardiovascular diseases. Furthermore, the non-enzymatic role of ACE-2 gives rise to a Hartnup disease, a phenocopy involving microbiota. With this chapter, we intent to explore the key pathways involved in SARS-CoV-2 infection, from the host perspective, considering our hypothesis related to transporter of neutral amino acids, which includes tryptophan precursor of serotonin and kynurenine.

The Causative Agent of FMD Disease

Foot-and-mouth disease (FMD) is an acute infection of cloven-hoofed animals caused by foot-and-mouth disease virus (FMDV). It is one of the most serious infectious diseases affecting animal husbandry and a major impediment to international trade in livestock and their products. Foot-and-mouth disease virus (FMDV), a member of the Picornaviridae family of Aphthovirus, is an icosahedral virus without envelope, 25–30 nm in diameter, containing about 8.4 kb of positive-sense single-stranded RNA. The virus exists in seven different serotypes: A, O, C, Asia1, SAT1, SAT2, and SAT3, but a large number of subtypes have evolved in each serotype. This chapter reviews the genome, structure, serotype, and epidemiology of FMDV, which will help people to further explore the mechanism of the interaction between foot-and-mouth disease virus and host and provide reference for scientific prevention and control of FMDV.