Herbal Drug use in Sickle Cell Disease Management; Trends and Perspectives in Sub-Saharan Africa - A Systematic Review

Introduction: Nigeria has the largest burden of Sickle Cell Disease (SCD) with estimated 100,000 new born affected annually. SCD is a Hemoglobin (Hb) disorder with the major form resulting from the substitution of a polar glutamate (Glu) by non-polar Valine (Val) in an invariant region of Hbβ chain-subunit. Species of Hb found in the sickle cell trait are HbA and HbS in a 60:40 proportion, in SCD only HbS, in the HbC disease only HbC, and in the SC disease it's HbS and HbC in a 50:50 equal proportion. Objective: This paper reviews herbal medicines usage in sub-Saharan Africa (sSA) to ameliorate the crisis associated with SCD. The model Hb tetramer suggests a higher membrane affinity of HbS and HbC, promoting dehydration of RBCs, with concomitant in vivo crystallization. Some drawbacks using these herbal drugs include; poor bioavailability and the lack of proper pharmacovigilance monitoring procedures arising from weak governance structure combined with under reporting of herbal usage to physicians were discussed. Probable epigenetic loci that could be targeted using phytomedicines for effective SCD management were also discussed. Methods: Using search engines, several databases including Google scholar, PubMed, Academic Resource Index were utilized as a source for relevant publications/ literature. The protein coordinates for the Hb tetramer were obtained from the Protein Data Bank (PDB). Conclusion: Manipulation of epigenetics to achieve better SCD management involves careful thinking. Herein, we discuss some epigenetic interactions that could be putatively tweaked with a view of enhancing soluble bioactive small molecular components with the potential to reactivate γ -globin genes, thereby boosting immune response in patient with SCD.