Isolation, purification, and characterization of a lectin from Cassia senna seeds with analgesic and gastroprotective effects

Abstract

Cassia senna, famous for its medicinal qualities, has been crucial in traditional medicine, providing remedies for many ailments. Its seeds, which are abundant in bioactive compounds such as lectins, have significant pharmaceutical potential. In this study, we investigated the biochemical intricacies and therapeutic potential of CsSL, a lectin found in Cassia senna seeds. Hemagglutination assays revealed robust CsSL activity, reaching its peak with 50 mM Tris–HCl buffer at pH 7.5. Ammonium sulfate fractionation was used to purify CsSL, with Fr40 showing the highest activity, confirming successful isolation. GlcNAc-agarose affinity chromatography further purified CsSL, showing its affinity for galactose residues. CsSL is stable, retains its full activity for 45 min at 30–40 °C, and exhibits pH dependence, with peak hemagglutinating activity occurring between pH 3.5 and 4.5 and sharply declining beyond pH 7. N-bromosuccinimide (NBS) modification showed that half of CsSL's tryptophan residues is crucial for its activity, as evidenced by decreased lectin activity. Therapeutically, CsSL demonstrated notable analgesic effects in acetic acid-induced writhing and thermal sensitivity tests. The 12 mg/kg dose particularly showed a remarkable antinociceptive effect (p < 0.05), completely reducing the writhing reflex by 100 % compared to that of the negative control Moreover, CsSL had potent gastroprotective effects, reducing ethanol-induced gastric lesions in a dose-dependent manner. Notably, doses of 0.25 mg/kg and 0.5 mg/kg provided substantial stomach lining protection (p < 0.05), outperforming the standard ulcer medication pantoprazole. CsSL exhibits promise for pain relief and ulcer prevention, with significant analgesic and gastroprotective effects. However, further research is needed to fully understand its underlying mechanisms and clinical applications, as this research has exciting potential in biomedicine and biotechnology.