Hyperglycemia in Cats Infected by SARS-CoV-2: Pancreatic Alterations and Potential Antiviral Therapeutics

Cats represent a susceptible host and a possible translational model for investigating coronavirus pathogenesis and therapeutics. Recent immunohistochemical (IHC) and histopathological studies in both human and feline tissues have demonstrated SARS-CoV-2 nucleocapsid protein (NP) and spike protein expression within pancreatic islet cells, following a classic temporal infection course. Notably, IHC analysis also reveals NP expression within exocrine ductal epithelial cells. Given that ductal epithelium functions as an islet progenitor pool during tissue injury or metabolic stress, pancreotropic coronaviruses may gain access to the endocrine compartment by exploiting this intrinsic cellular differentiation pathway. Although the precise mechanisms governing intra-islet viral entry remain to be elucidated, this review highlights the capacity of SARS-CoV-2 to compromise both the exocrine (digestive) and endocrine functions of the pancreas. Finally, we evaluate the therapeutic potential of direct-acting antivirals—specifically RNA-dependent RNA polymerase (RdRp) and protease inhibitors—as monotherapies and in synergistic combination to limit pancreatic injury and mitigate the diabetogenic effects of coronaviruses across both acute infection and post-acute sequelae, such as human long-COVID syndrome.