• To figure out the pathogenesis of HE, the improvement of the animal model is warranted. • TAA has been introduced as a valid model because it mimics many pathological features of patients with ALF and HE. • TAA as a chemical agent leads to liver injury by triggering the production of ROS and proinflammatory cytokines. • TAA causes impairment of CBF, gliopathy, neuroinflammation, and neurological impairments that are seen in ALF patients.

Coronavirus disease 2019 (COVID-19) was reported at the end of 2019 in China for the first time and has rapidly spread throughout the world as a pandemic. Since COVID-19 causes mild to severe acute respiratory syndrome, most studies in this field have only focused on different aspects of pathogenesis in the respiratory system. However, evidence suggests that COVID-19 may affect the central nervous system (CNS). Given the outbreak of COVID-19, it seems necessary to perform investigations on the possible neurological complications in patients who suffered from COVID-19. Here, we reviewed the evidence of the neuroinvasive potential of coronaviruses and discussed the possible pathogenic processes in CNS infection by COVID-19 to provide a precise insight for future studies.

A common neuropsychiatric complication of advanced liver disease, hepatic encephalopathy (HE), impacts the quality of life and length of hospital stays. There is new evidence that gut microbiota plays a significant role in brain development and cerebral homeostasis. Microbiota metabolites are providing a new avenue of therapeutic options for several neurological-related disorders. For instance, the gut microbiota composition and blood-brain barrier (BBB) integrity are altered in HE in a variety of clinical and experimental studies. Furthermore, probiotics, prebiotics, antibiotics, and fecal microbiota transplantation have been shown to positively affect BBB integrity in disease models that are potentially extendable to HE by targeting gut microbiota. However, the mechanisms that underlie microbiota dysbiosis and its effects on the BBB are still unclear in HE. To this end, the aim of this review was to summarize the clinical and experimental evidence of gut dysbiosis and BBB disruption in HE and a possible mechanism.