Seminar of Physics of the Living State

(The Applied Physics Scientific Section)

(*) Summary: Sickle Cell Disease (SCD) is one of the most neglected diseases of the 21st century with an important death rate in children living in the third world, especially in Africa. Like malaria, SCD is also a major public health problem and is the first genetic disease by the number of affected people in tropical Africa regions. Clinical symptoms of SCD are associated with the polymerization of unstable haemoglobin S under anoxic conditions. These symptoms include erythrocytes shape and membrane modification, as well as anaemia.  Some agents were developed by rational drug design to inhibit the red blood cells sickling process. Most of these agents, unfortunately, did not show promising success in terms of clinical use. Conventional treatments are expensive and unaffordable by the rural populations.
During the last few years, the use of medicinal plants is explored as a therapeutic approach that can relieve this disease. Indeed, the use of medicinal plants seems to be simple, inexpensive, and an appropriate strategy for disease control in developing countries.The progress made during these last few years in biochemistry and cellular biology of SCD has indicated that three main targets are of particular importance for chemotherapy. These include haemoglobin S polymerization and stability of the erythrocyte membrane.
Consequently, the same tests such as the Emmel-, Itano- and the membrane osmotic fragility tests are used to evaluate in vitro the effect medicinal plants extracts on erythrocyte shape modification, haemoglobin S aggregation in low O2 pressure conditions and membrane stability. The first plant that showed an antisickling activity was Fagara zanthoxyloides. Some other plants extracts have showed antisickling activity as well.
The ethnobotanical investigations carried out during the last few years by our research team have revealed that 53 medicinal plant species belonging to 30 different families are used by Congolese traditional healers for the treatment of SCD in the Democratic Republic of Congo. A preliminary screening for the in vitro antisickling activity using the Emmel test has indicated that the polar extracts of 50 of 53 plants studied possess a significant sickling suppressive rate in hypoxic conditions. Bio-guided extraction has indicated that anthocyanins extracts would be among the secondary metabolites responsible of the antisickling activity. One of these plants Vigna unguiculata (known as Cowpea or Black-eye Pea) is now been tested as medicinal food in sickle cell disease.

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(**) Professor Pius Mpiana  Tshimankinda is at the University of Kinshasa in the Democratic Republic of Congo. He earned a Master's Degree in physical chemistry at his university, as well as a Master in integrated management of tropical forests and Ph. D. in physical chemistry in 2003.

At present he is Vice-Head of the Department of Chemistry in charge of research, and Professor at the Faculty of Science since 2003. He is also a Visitor Professor at  some other Congolese Universities. Since last year  Professor Mpiana is one of our Senior Associate Members in the Program of Physics of the Living State.

He is responsible or co-responsible of some research projects among which three TWAS projects. He is a member of a natural products research network of Eastern and Central Africa and a member of the editorial board of some journals.

Professor Mpiana has received several national and international prizes for his work, not only in science, but also for distinguished service at his university and for work in society. He has several patents to his credit and is the author of a book on Medical Biophysics, besides numerous papers in specialized journals, among which 18 are on the subject of his forthcoming seminar at the Centre.