Pro-apoptotic activity of new triterpenoid saponins from the roots of Albizia adianthifolia (Schumach.) W.Wight.

As part of our study of the proapoptotic function of saponins from Cameroonian's Albizia genus, phytochemical investigation of the roots of Albizia adianthifolia led to the isolation of three new triterpenoid saponins, named adianthifoliosides GI (13). Their structures were established on the basis of extensive analysis of 1D and 2D NMR (H-, C NMR, DEPT, COSY, TOCSY, NOESY, HSQC, HSQC-TOCSY and HMBC) and HRESIMS experiments, and by chemical evidence as 3-O-[β-d-glucopyranosyl-(1 → 2)-β-D-fucopyranosyl-(1 → 6)-β-d-glucopyranosyl]-21-O-{(2E,6S)-2-(hydroxymethyl)-6-methyl-6-O-{4-O-[(2E,6S)-2,6-dimethyl-6-O-(β-D-quinovopyranosyl)octa-2,7-dienoyl]-(β-D-quinovopyranosyl)octa-2,7-dienoyl]}acacic acid-28-O-β-d-xylopyranosyl-(1 → 3)-[5-O-acetyl-α-L-arabinofuranosyl-(1 → 4)]-α-L-rhamnopyranosyl-(1 → 2)-β-d-glucopyranosyl ester (1), 3-O-[β-d-glucopyranosyl-(1 → 2)-β-D-fucopyranosyl-(1 → 6)-β-d-glucopyranosyl]-21-O-{(2E,6S)-2-(hydroxymethyl)-6-methyl-6-O-{4-O-[(2E,6S)-2,6-dimethyl-6-O-(β-D-quinovopyranosyl)octa-2,7-dienoyl]-(β-D-quinovopyranosyl)octa-2,7-dienoyl]}acacic acid 28-O-β-d-xylopyranosyl-(1 → 3)-[α-L-arabinofuranosyl-1 → 4)]-α-L-rhamnopyranosyl-(1 → 2)-β-d-glucopyranosyl ester (2), and 3-O-[β-d-glucopyranosyl-(1 → 2)-β-D-fucopyranosyl-(1 → 6)-β-d-glucopyranosyl]-21-O-{(2E,6S)-2-(hydroxymethyl)-6-methyl-6-O-{4-O-[(2E,6S)-2,6-dimethyl-6-O-(β-D-quinovopyranosyl)octa-2,7-dienoyl]-4-O-[(2E,6S)-2,6-dimethyl-6-O-(β-D-quinovopyranosyl)octa-2,7-dienoyl]-β-D-quinovopyranosyl}-2,6-dimethylocta-2,7-dienoyl}acacic acid 28-O-β-d-xylopyranosyl-(1 → 3)-[α-L-arabinofuranosyl-1 → 4)]-α-L-rhamnopyranosyl-(1 → 2)-β-d-glucopyranosyl ester (3). The apoptotic effect of saponins 1-3 was evaluated on the A431 human epidermoid cancer cell.

Structural determination of two new acacic acid-type saponins from the stem barks of Albizia zygia (DC.) J. F. Macbr.

As a continuation of our interest in the study of triterpenoid saponins from Albizia zygia, phytochemical investigation of its stem barks led to the isolation of two new oleanane-type saponins, named zygiaosides C-D (1-2). Their structures were established on the basis of extensive analysis of 1D and 2D NMR (1H-, 13C NMR, DEPT, COSY, TOCSY, ROESY, HSQC and HMBC) experiments, HRESIMS studies, and by chemical evidence as, 3-O-[ β-d-glucopyranosyl-(1→2)-[α-l-arabinopyranosyl-(1→6)]-β-d-glucopyranosyl]-21-O-[(2E,6S)-2,6-dimethyl-6-O-(β-d-quinovopyranosyl) octa-2,7-dienoyl]acacic acid 28-O-α-l-arabinofuranosyl-(1→4)-[β-d-glucopyranosyl-(1→3)]-α-l-rhamnopyranosyl-(1→2)-β-d-glucopyranosyl ester (1) and 3- O-[β-d-glucopyranosyl-(1→2) -[ β-d-fucopyranosyl-(1→6)]-β-d-glucopyranosyl]-21-O-[(2E,6S)-2,6-dimethyl-6-O-(β-D-quinovopyranosyl) octa-2,7-dienoyl]acacic acid 28-O-α-l-arabinofuranosyl-(1→4)-[β-d-glucopyranosyl-(1→3)]-α-l-rhamnopyranosyl-(1→2)-β-d-glucopyranosyl ester (2).

New Cytotoxic Triterpenoid Saponins from the Roots of Albizia gummifera (J.F.Gmel.) C.A.Sm.

As part of our search for new bioactive saponins from Cameroonian medicinal plants, two new oleanane-type saponins, named gummiferaosides D and E (1 and 2), along with one known saponin, julibroside J (3), were isolated from the roots of Albizia gummifera. Their structures were established on the basis of extensive 1D- and 2D-NMR ( H- and C-NMR, DEPT, COSY, TOCSY, NOESY, HSQC, HSQC-TOCSY, and HMBC) and HR-ESI-MS studies, and by chemical evidence. The apoptotic effect of saponins 1 - 3 was evaluated on the A431 human epidermoid cancer cell.

Phenotype-specific apoptosis induced by three new triterpenoid saponins from Albizia glaberrima (Schumach. & Thonn.) Benth.

As part of our search of new bioactive saponins from Cameroonian medicinal plants, phytochemical investigation of the roots of Albizia glaberrima led to the isolation of three new oleanane-type saponins, named glaberrimosides A-C (1-3). Their structures were established by direct interpretation of their spectral data, mainly HRESIMS, 1D NMR (1H, 13C NMR, and DEPT) and 2D NMR (COSY, ROESY, HSQC and HMBC) as 3-O-[α-L-arabinopyranosyl-(1 → 6)-[β-D-glucopyranosyl-(1 → 2)]-β-D-glucopyranosyl]-28-O-[β-D-glucopyranosyl-(1 → 6)-[β-d-glucopyranosyl-(1 → 2)]-β-D-glucopyranosyl]-oleanolic acid (1), 3-O-[α-L-arabinopyranosyl-(1 → 6)-[β-D-glucopyranosyl-(1 → 2)]-β-D-glucopyranosyl]-28-O-[β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl]-oleanolic acid (2), and 3-O-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl]-28-O-[β-D-glucopyranosyl-(1 → 6)-[β-D-fucopyranosyl-(1 → 2)]-β-D-glucopyranosyl]-oleanolic acid (3). The pro-apoptotic effect of the three saponins was evaluated on three human cell lines (pancreatic carcinoma AsPC-1, hematopoietic monocytic THP-1, and human fibroblast cell line BJ).

Cyclooxygenase-2 expression and role of vasoconstrictor prostanoids in small mesenteric arteries from patients with Crohn's disease.

Background: The present study investigates the vascular reactivity and the involvement of nitric oxide and prostanoids in regulating vasoconstriction of small mesenteric arteries from patients with Crohn's disease (CD) to understand the vascular component of this pathology.

Methods And Results: An increased production of proinflammatory cytokines (tumor necrosis factor-alpha and interleukins 1beta, 6, and 8) has been observed in biopsy specimens of inflammatory intestinal mucosa. However, contractile responses of small mesenteric arteries from CD patients in response to norepinephrine were not changed ex vivo when compared with controls.