Traditional herbal management of sickle cell anemia: lessons from Nigeria

Abstract

Background. Patients in West Africa where sickle cell anemia (SCA) is endemic have for ages been treated with natural products, especially herbs, as, is still the case in rural communities. Objective. In this paper we look closely at some of these herbs to see if there are any lessons to be learnt or clues to be found for optimizing the treatments based on them, as had been done in the case of NIPRISAN, which was developed from herbs in Nigeria based on Yoruba Medicine. Methods. Select publications on SCA, its molecular biology and pathology, and actual and experimental cases of herbal treatment were perused in search of molecular clues that can be linked to chemical constituents of the herbs involved. Results. The study revealed that during the last 2-3 decades, much progress was made in several aspects of SCA pharmacology, especially the approval of hydroxyurea. As for SCA herbalism, this paper revealed that antisickling herbs abound in West Africa and that the most promising may yet be found. Three new antisickling herbs (Entandrophragma utile, Chenopodium ambrosioides, and Petiveria alliacea) were reported in May 2011. At NIPRD, where NIPRISAN was developed, three other recipes are currently awaiting development. Conclusion. The study raised the hope that the search in the Tropics for more effective herbal recipes for managing sickle cell anaemia will be more fruitful with time and effort.

Figure 1

Manifestations of SCA and strategies for management including herbal treatment. The two major pathologies of SCA are hemolytic anemia and vasoocclusion with pain especially in the limbs. Acute chest syndrome, which can result from infections, is the leading cause of death. Neurologic complications such as stroke and hemorrhage can occur. Aplastic crisis is most often the result of infection with Parvovirus B19, which results from temporary cessation of RBC production. Genitourinary-hematuria, renal failure, and priapism may occur. Cholelithiasis due to severe hemolysis can develop into acute cholecystitis due to the formation of pigmented gallstones [–13].

Figure 2

Biosynthesis and relationship of shikimic acid to “alternative aspirins” and “vanilloids”. The shikimic acid pathway is a key biosynthetic pathway for several phytochemicals known for their medicinal attributes. The Figure illustrates the biosynthesis of shikimic acid from pyruvic acid and erythrose and the relationship between the acid and its byproducts and intermediates, some of which possess aspirin-like effects, like analgesia and desickling of sickled RBCs. Such byproducts/intermediates include salicyclic acid derivatives, vanillin, piperine, capsaicin, and cubebin. Piperine, capsaicin, and cubebin as byproducts of shikimic acid are the likely antisickling agents Niprisan [14]. It is of note that Ouattara [15] had attributed the antisickling properties Fagara zanthoxyloides to divanilloylquinic acids.