High Flavonoid Content in Apium graveolens Nanocrystals Improves Colitis in Dextran Sodium Sulfate-induced Colitis Mice.

AIM: To develop medicinal plant nanoparticles as colitis alternative/supplementary therapy.

BACKGROUND

Limited reports about the effectiveness of medicinal plant nanocrystals in treating or preventing colitis.

OBJECTIVES

We investigated the effect of nanonizing Apium graveolens (AG) on improving dextran sodium sulfate (DSS)- induced colitis.

METHODS

Nanonization was performed via the bead milling process. The nanocrystal product was characterized (i.e., particle size, zeta potential (ZP), polydispersity index (PDI) values) and freezedried. Total flavonoids and phenolic compounds in nanocrystal products were compared with ethanolic extract of AG (AGEE). Anti-colitis activity of AG-nanocrystal water suspensions (AGNS) was compared to AG bulk powder suspensions (AGBS). Colitis severity was determined via physiological, macroscopic, and microscopic colon assessment. In addition, the fecal Enterobacteriaceae population and urine glucose levels were determined.

RESULTS AND DISCUSSION: The AG nanoparticle products are 200-400 nm, with PDI values 0.5-0.6, and ZP values -12 to -20 mV. The total flavonoid and phenolic compounds of AGNS were 115.12±4.32 ppm and 37.11±0.34 ppm, respectively. This value is higher compared to the content in AGEE. AGNS (350 mg/kg) improves physiological (i.e., fecal blood), macroscopic (i.e., length, diameter), and microscopic (i.e., structure and immune cell infiltration) colon conditions in a comparable level to the positive control of 5-aminosalicylic acid (100 mg/kg). AGNS have a compelling ability to restore colon microscopic and Enterobacteriaceae population compared to AGBS (700 mg/kg). AGNS (350 mg/kg) also recovered colon permeability as marked by the lower urine glucose concentration (9.90±0.15 mg/dL) compared to colitis mice (12.43±0.09 mg/dL).

CONCLUSION

The nanonization of AG contributes to improved anti-colitis activities compared to AGBS. Nanonization of medicinal plants will reduce organic solvent extraction, which supports the sustainable development goals.