Objective: Andrographis paniculata is a well-known medicinal plant in Southeast Asia, India and China. The plant contains andrographolide (AN), a very important phytochemical used in various health problems. However, AN is low in oral absorption bioavailability of AN due to the rapid clearance and high protein binding capacity. Methods: The present study was aimed to develop a nano-phytovesicular formulation of semi-purified AN extracts from a naturally occurring phospholipid (soya phosphatidylcholine) in order to increase the oral absorption and antihyperglycemic activity in rats. Results: The nano-phyto vesicle of semi-purified AN extracts equivalent to 25 mg /kg AN significantly protected the hyperglycemic condition of rats. The in vitro and in vivo experiments results proved that the nano- phytovesicular system of plant extracts containing AN produced better oral absorption, bioavailability and improved antihyperglycemic activity compared with that of free AN at dose of 50 mg/kg. Conclusion: Hence, the prepared semi-purified extract nano-phytovesicular system is helpful in solving the problem of rapid clearance of AN.

As of August 16,2021,there have been 207,173,086 confirmed cases and 4,361,996 deaths due to the coronavirus disease(COVID-19),and the pandemic remains a global challenge.To date,no effective and approved drugs are available for the treatment of COVID-19.Angiotensin-converting enzyme 2(ACE2)plays a crucial role in the invasion into host cells by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the etiological agent of COVID-19.Notably,ACE2 density is influenced by medical con-ditions,such as hypertension,or by drugs,including angiotensin-converting enzyme inhibitors(ACEIs)and angiotensin receptor blockers(ARBs),which can change the fate of SARS-CoV-2 infectivity.ACE2 is a target for these drugs and can be manipulated to limit the viral entry and replication within the cells.Different strategies aimed at blocking ACE2 with small molecules,peptides,and antibodies,or by neutralizing the virus through its competitive binding with human recombinant soluble ACE2(hrsACE2)are currently under investigation.In this article,we review the current state of knowledge that em-phasizes the need to find effective therapeutic agents against COVID-19 by exploiting ACE2 as a potential target.The increased soluble ACE2 levels and the application of hrsACE2 in patients with COVID-19 can be implemented to control the disease.It has not yet been established whether hypertension and other comorbidities,independent of age,have a direct role in COVID-19.Therefore,the use of renin-angiotensin system inhibitors,ACEls and ARBs,should not be discontinued during COVID-19 treatment.