In vitro effects of anthocyanin extracts from Justicia secunda Vahl on the solubility of haemoglobin S and membrane stability of sickle erythrocytes.
BACKGROUND
Sickle cell disease or drepanocytosis is caused by the polymerisation of abnormal haemoglobin S when oxygen tension decreases. This lead to the changes in the shape of red blood cells and anaemia. It has also been postulated that the red cells of patients with sickle cell disease contain a higher than normal concentration of calcium ions. These ions are bound to membrane proteins resulting in dehydration and loss of red blood cell deformability and cell-to-cell adherence. Anthocyanins extracted from some Congolese plants used in traditional medicine against sickle cell disease have recently been shown to have anti-sickling activity in vitro. Justicia secunda is a plant used in Congo by Jehovah's Witnesses, well known for their refusal of blood transfusions, against anaemia.


METHODS
Emmel, Itano and osmotic fragility tests were used to test the effect of anthocyanin extracts from Justicia secunda leaves on haemoglobin S solubility and sickle cell membrane stability.


RESULTS
Anthocyanins from Justicia secunda were found to possess anti-sickling activity. Treated SS red blood cells recovered a normal, classical biconcave form with a radius of 3.3±0.3 μm, similar to that of normal erythrocytes. The solubility of deoxyhaemoglobin S increased and the osmotic fragility of drepanocytes decreased upon treatment with anthocyanin extracts.


CONCLUSIONS
These findings suggest that anthocyanin extracts play a role in both stabilising the red blood cell membrane and inhibiting polymerisation of haemoglobin S. This provides a possible molecular basis for earlier reports on the anti-sickling properties of anthocyanins from some Congolese plants and their use in the management of sickle cell disease by Congolese traditional healers.
Department of Chemistry, Faculty of Sciences B.P. 190, University of Kinshasa, Kinshasa XI, D.R. Congo.
Pius T
PT
Mpiana
KotoTe Niwa N
KN
Ngbolua
Matthieu T
MT
Bokota
Teddy K
TK
Kasonga
Emmanuel K
EK
Atibu
Damien S T
DS
Tshibangu
Virima
V
Mudogo
D027901:Acanthaceae / Q000737:chemistry*; D000755:Anemia, Sickle Cell / Q000188:drug therapy*; D000872:Anthocyanins / Q000302:isolation & purification / Q000627:therapeutic use*; D000986:Antisickling Agents / Q000302:isolation & purification / Q000627:therapeutic use*; D004910:Erythrocyte Membrane / Q000187:drug effects; D004912:Erythrocytes / Q000187:drug effects* / Q000473:pathology; D006451:Hemoglobin, Sickle / Q000378:metabolism*; D006801:Humans; D009996:Osmotic Fragility / Q000187:drug effects; D010936:Plant Extracts / Q000302:isolation & purification / Q000627:therapeutic use; D018515:Plant Leaves / Q000737:chemistry; D012995:Solubility
D000872:Anthocyanins; D000986:Antisickling Agents; D006451:Hemoglobin, Sickle; D010936:Plant Extracts