Anti sickling potential and chemical profiling of traditionally used Woodfordia fruticosa (L.) Kurz leaves

Abstract

Woodfordia fruticosa (L.) Kurz is a widely used plant in traditional medicine systems. The tribal communities of Amarkantak, Madhya Pradesh (India) are using this plant for the treatment of general weakness, blood related complications like blood deficiency, blood purification and for the treatment of symptoms related to sickle cell disease (SCD). SCD is a genetic disease with life threatening complications. In the absence of any drugs without any side effects, the alternative plant based therapies that may either reduce/ reverse the sickling of the red blood cells can be safe and effective therapeutic agents. We evaluated W. fruticosa extracts for phytoconstituents, anti-oxidant and anti-inflammatory properties. Anti-sickling properties of the extracts were evaluated by estimation of reverse sickling, polymerization inhibition and osmotic fragility assays. Chemical profiling of the methanol extract was done using LC-MS analysis. Phytochemicals such as alkaloids, steroids, tannin, and saponins were present in all the extracts. Methanol extract displayed maximum reversal (66 ± 1%) of sickled Red blood Cells (RBC) and significantly inhibited Hb polymerization. The hexane and methanol extracts led to minimum hemolysis of sickled RBC in the osmotic fragility assays. Total tannin (365 ± 2.4 TAE) content was highest in acetone extract, while the total flavonoid and phenolic content (156.9 ± 2.0 QE) and (113.7 ± 0.7 GAE) were highest in methanol extract. The methanol extract displayed minimum IC₅₀ (8.1 ± 1.5) in 2, 2-diphenylpicrylhydrazyl (DPPH) while the acetone extract had minimum IC₅₀ (215.8 ± 5.7) in 2,2′-azino-bis 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assay. The hexane extract displayed maximum Ferric reducing anti-oxidant power (FRAP) value (1.5 ± 0.5 mM Fe(II)/mg dry weight) that were higher than methanol and aqueous extracts (1.45 ± 0.1, 1.45 ± 0.05 mM Fe(II)/mg dry weight). The methanol extract provided maximum RBC protection from hemolysis (73.8 ± 0.8%). Maximum Lipoxygenase (LOX) inhibition was observed by the acetone and methanol extracts at 400 μg/mL while the hexane extract displayed maximum Xanthine oxidase (XO) inhibition (57.0 ± 0.5%). LC-MS profiling of the methanol extract identified several secondary metabolites that might be responsible for the observed activities. The results validate the traditional use of W. fruticosa and present us with potential compounds for further development of novel anti sickling agents.