Alyssum homolocarpum seeds: phytochemical analysis and effects of the seed oil on neural stem cell proliferation and differentiation.

Pharmacognostic evaluation of medicinal plants may assess their current applications and possibly results in finding new active components. In this study, ash and extractive values and high performance thin layer chromatography fingerprints of Alyssum homolocarpum (Brassicaceae) seed extracts were investigated to elucidate its composition. Differential scanning calorimetry and gas chromatography-mass spectrometry analysis were employed to determine the components of A. homolocarpum seed oil (AHO). Neurosphere assay, in vitro differentiation and immunofluorescence analysis were performed to evaluate the effects of oral administration of AHO (0.5 or 1 g/kg/day for 14 days) on proliferation and differentiation of neural stem cells (NSCs) in adult male BALB/c mice. Total, acid-insoluble and water-soluble ash values were determined as 45.83 ± 5.85, 6.67 ± 2.89 and 28.33 ± 2.89 mg/g, respectively. The extractive values were 4.90, 0.43 and 0.56 % (w/w) for n-hexane, dichloromethane and ethanolic extracts, respectively. Interestingly, AHO was mainly composed of α-linolenic acid (89.71 %), β-sitosterol (3.3 mg/g) and campesterol (0.86 mg/g). Administration of AHO at 1 g/kg/day significantly increased proliferation of NSCs, as evidenced by an increase in mean neurosphere-forming frequency per brain (872.7 ± 15.17) and neurosphere diameter (101 ± 2.48 µm) compared to the control group (424.3 ± 59.29 and 78.63 ± 1.7 µm, respectively; P < 0.05). AHO treatment did not affect in vitro differentiation of the harvested NSCs. Our data show that A. homolocarpum seed oil is a rich source of α-linolenic acid and β-sitosterol with potential therapeutic application to enhance NSC proliferation and recruitment in neurological diseases.