Milk Oligosaccharides and Lectins as Candidates for Clinical Trials against Covid-19

Background: Covid-19 pandemic is causing a very high death toll around the world and a severe fall in the global economy. Many clinical trials are currently underway to check the effectiveness of some known drugs. The physiopathology associated with the virus infection is currently better understood and good prophylactic drug therapies are implemented, such as antibiotics and blood thinners, though, no specific drugs against SARS-Cov-2 were developed yet. Objective: In the present research work, it is aimed to carry out a bibliographic investigation on some active molecular species that could be used against Covid-19, based on their chemical properties to bind to glycoproteins. In the case of SARS-Cov-2, the targeted glycoprotein is the surface virus spike S glycoprotein, that the virus uses to attach to and invade human cells. It is of high pharmacological value to investigate possible active natural substances endowed with a property to bind glycoproteins. In this line of research, oligosaccharides and lectins are two molecular species that have glycoprotein binding properties. Methods: A bibliographic research was carried out on oligosaccharides and lectins in various sources of scientific publications. Relevant chemical and pharmacological properties of oligosaccharides and lectins were searched and their main natural sources were identified. Results: In the present paper, I summarize some scientific evidence to support the therapeutic potential of camel milk as a source of oligosaccharides and its possible use as a functional diet in parallel to drug therapies of Covid-19. On the other hand, sugar and glycoprotein binding properties of some lectins of plant and seaweed origin are reported, and their pharmaceutical use is underlined. Conclusion: In the present study, scientific evidence was documented that encouraged further clinical investigations on camel milk oligosaccharides and lectins of plant and seaweed origin in the management of Covid-19 physiopathology.