Anti-inflammatory, antioxidant and anti-acetylcholinesterase activities of Bouvardia ternifolia: potential implications in Alzheimer's disease.

Bouvardia ternifolia has been used medicinally to treat inflammation. In the present study, we investigate the anti-Alzheimer's potential effect of the hydroalcoholic extract of B. ternifolia through evaluation of anti-inflammatory and antioxidant activities, quantification of the percentage inhibition of acetylcholinesterase activity, protection effect against ß-amyloid fibrillar-induce neurotoxicity, and the identification of the main constituents. Our results show that B. ternifolia extract and ethyl acetate fraction induced anti-inflammatory effects by reducing inflammation by >70 %, while antioxidant test revealed significant IC50 values for flavonoid content fraction (30.67 ± 2.09 µg/ml) and ethyl acetate fraction (42.66 ± 0.93 µg/ml). The maximum inhibition of acetylcholinesterase was exhibited by scopoletin content fraction (38.43 ± 3.94 %), while ethyl acetate fraction exerted neuroprotective effect against ß-amyloid peptide (83.97 ± 5.03 %). Phytochemical analysis, showed the presence of 3-O-quercetin glucopyranoside (415 mg/g), rutin (229.9 mg/g), ursolic and oleanolic acid (54 and 20.8 mg/g respectively), 3-O-quercetin rhamnopyranoside (12.8 mg/g), chlorogenic acid (9.5 mg/g), and scopoletin (1.38 mg/g). Our findings support the use of B. ternifolia since the extract induced significant neuroprotection against ß-amyloid peptide, anti-inflammatory, antioxidant and anti-acetylcholinesterase effects that could be attributed to its contents of polyphenols, coumarins, and triterpenes, and encourage further studies for development of this extract as therapeutic agent in treatment of Alzheimer's disease.

Inhibition of acetylcholinesterase activity by hidroalcoholic extractand their fractions of Bouvardia ternifolia (Cav. ) Shcltdl (Rubiaceae) / Inhibición de la actividad de acetilcolinesterasa por el extracto hidroalcohólico y sus fracciones de Bouvardia ternifolia (Cav. ) Shcltdl (Rubiaceae)

The hydroalcoholic extract (BtHA) and its fractions of Bouvardia ternifolia were evaluated as inhibitors of the activity of the acetylcholinesterase enzyme utilizing the in vitro method (Ellman). BtHA inhibited the acetylcholinesterase enzyme competitively (IC50 = 0.6 ug/ml); the ethyl acetate fraction (BtF-AcOEt) caused mixed-type inhibition (IC50 = 0.96 ug/ml). A fraction insoluble on methanol (Bt-Faq-1) showed a mixed-type inhibition (CI50 = 0.96 ug/ml). Finally, the methanol-soluble fraction (Bt-Faq-2), presented complex, mixed-type inhibition that corresponds to the C5 system ( alpha= 0.740 and beta = 0.842). Rutin, quercetin, kaempferol and ursolic acid were detected by HPLC and the concentration of these compounds was different in each fraction.

El extracto hidroalcohólico (BtHA) y fracciones provenientes de Bouvardia ternifolia fueron evaluadas como inhibidores de la enzima acetilcolinesterasa utilizando el método enzimático propuesto por Ellman. BtHA inhibe a la enzima de manera competitiva (IC50 = 0.6 ug/ml); la fracción de acetato de etilo (BtF-AcOEt) provoca una inhibición mixta (IC50 = 0.96 ug/ml). La fracción insoluble en metanol (Bt-Faq-1) mostró una inhibición tipo mixta (CI50 = 0.96 ug/ml). Finalmente la fracción soluble en metanol, Bt-Faq-2, inhibe a la enzima presentando una inhibición mixta que corresponde a un sistema C5 ( alfa= 0.740 and beta= 0.842). Mediante HPLC se detectó rutina, quercetina, canferol y ácido ursólico la concentración de estos compuestos fue diferente en cada fracción.