(2) The proportion of infected patients with elevated serum transaminase levels is higher in adults than in children and in men than in women, respectively. in hepatocytes during shock and hypoxic conditions may lead to cell death. The subsequent marked increase in reactive oxygen species and their peroxidation products can act as a second messenger, activating redox-sensitive transcription factors, and further amplifying the release of multiple proinflammatory factors, causing liver damage.30 All the aforementioned findings suggest that pneumonia-associated hypoxia is one of the most important factors causing secondary liver injury in COVID-19 patients. In summary, the COVID-19-related liver dysfunction may (-)-Borneol be considered as the result of secondary liver damage caused mainly by several factors, such as the use of potentially hepatotoxic drugs, systemic inflammatory response, respiratory distress syndrome-induced hypoxia, and multiple organ failure. In addition, critically ill COVID-19 patients with severe liver dysfunction are also more likely to have a poorer prognosis. Treatment options for COVID-19-related liver dysfunction Presently, there is no specific treatment for COVID-19 infection.31 Therefore, the cornerstone of (-)-Borneol COVID-19 management is patient isolation and supportive medical care where necessary, including pulmonary ventilation and prevention of the underlying inflammatory storm as well. 32 From the findings discussed above, however, we believe that it is also reasonable to explore novel treatments for COVID-19 targeting of the ACE2 receptor. The ACE2 cellular receptor is highly expressed in human lung tissues, gastrointestinal tract, liver, vascular endothelial cells, and arterial smooth muscle cells.33 In addition, skin, nasal cavity, and oral mucosa basal cells also express the ACE2 receptor. 27 All organs with high expression of the ACE2 receptor (-)-Borneol may be targeted by SARS-CoV-2 infection.34 Activation of the ACE2/Ang (1-7)/Mas signaling pathway or inhibition of the ACE/Ang II/AT1R pathway could be potential (-)-Borneol pathways for the treatment of COVID-19. For SARS-CoV-2-infected patients, both ACE-inhibitors and angiotensin-II-receptor antagonists might be used not only for treating high blood pressure but also for reducing systemic inflammatory response and improving patient mortality.35 Recently, Chen em et al. /em 36 reported that glycyrrhizic acid derivatives might also have antiviral activity against SARS-CoV-2. Glycyrrhizic acid is one of the first-line drugs for anti-inflammatory protection in liver (-)-Borneol disease, and it has been used in clinical practice for many years.37 In particular, glycyrrhizic acid is a triterpene glycoside isolated from the root of the licorice plant. ACE2 is a cellular type I membrane protein that is mostly expressed in the lungs, heart, kidneys, and intestine. Full-length ACE2 consists of an N-terminal peptidase domain and a C-terminal collectrin-like domain that ends with a single trans-membrane helix and a 40-residue intracellular segment.38 Glycyrrhizin has the potential to bind to ACE2 receptor with an Rabbit polyclonal to CDKN2A estimated G (kcal/mol) of -9, with the binding sites of ARG-559, GLN-388, ARG-393, and ASP-30.36 Conclusions Our review shows the following: (1) In highly epidemic areas of COVID-19 infection, such as Wuhan, China, the proportion of infected patients with abnormal liver function test results (mainly elevated serum AST levels) is greater than that observed in regions where a smaller proportion of cases of COVID-19 infection in the population have occurred. (2) The proportion of infected patients with elevated serum transaminase levels is higher in adults than in children and in men than in women, respectively. However, we suggest that further studies are needed to confirm these preliminary observations. In the meantime, we believe that the front-line medical staff should pay attention to liver function tests in patients infected with COVID-19. For those patients with a pre-existing history of liver diseases (especially older patients), special attention should be paid to monitoring hepatic changes caused by COVID-19, whilst carefully identifying the cause of the liver dysfunction.39 We also recommend that front-line medical staff should assess the use of appropriate hepatoprotective therapies, especially.