Protein Tyrosine Phosphatase-1B Inhibitory Activity of Isoprenylated Flavonoids Isolated from Erythrina mildbraedii

• Published in: Journal of natural products (Washington, D.C.) Vol. 69; no. 11; pp. 1572 - 1576
• Main Authors: Na, MinKyun, Jang, JunPil, Njamen, Dieudonné, Mbafor, Joseph Tanyi, Fomum, Zacharias Tanee, Kim, Bo Yeon, Oh, Won Keun, Ahn, Jong Seog
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 01-11-2006; Glendale, AZ American Society of Pharmacognosy
• Subjects: Biological and medical sciences; Cameroon; chalcone; chemical structure; enzyme inhibition; enzyme inhibitors; Erythrina; Erythrina - chemistry; Erythrina mildbraedii; Fabaceae; flavanones; flavonoids; Flavonoids - chemistry; Flavonoids - isolation & purification; Flavonoids - pharmacology; General pharmacology; Humans; Medical sciences; medicinal plants; Molecular Structure; Pharmacognosy. Homeopathy. Health food; Pharmacology. Drug treatments; Plant Bark - chemistry; Plant Roots - chemistry; Plants, Medicinal - chemistry; Protein Tyrosine Phosphatase, Non-Receptor Type 1; Protein Tyrosine Phosphatases - antagonists & inhibitors; protein-tyrosine-phosphatase; spectral analysis; Cameroon; Africa; Type 2 diabetes; Isozyme; Bark; Phosphoric monoester hydrolases; Esterases; Flavonoid; Medicinal plant; Dicotyledones; Angiospermae; Nutritional status; Below ground plant part; Obesity; Root; Enzyme; Pharmacognosy; Enzyme inhibitor; Isoprenoid; In vitro; Biological activity; Flavanone derivatives; Treatment; Leguminosae; Plant origin; Hydrolases; Isolation; Spermatophyta; Structural analysis; Protein-tyrosine-phosphatase
• ISSN: 0163-3864; 1520-6025
• DOI: 10.1021/np0601861

Inhibition of protein tyrosine phosphatase-1B (PTP1B) has been proposed as a therapy for treatment of type-2 diabetes and obesity. Bioassay-guided fractionation of an EtOAc-soluble extract of the root bark of Erythrina mildbraedii, using an in vitro PTP1B inhibitory assay, resulted in the isolation of three new isoprenylated flavonoids, abyssinone-IV-4‘-O-methyl ether (2), 7-hydroxy-4‘-methoxy-3‘-(3-hydroxy-3-methyl-trans-but-1-enyl)-5‘-(3-methylbut-2-enyl)flavanone (3), and abyssinone-VI-4-O-methyl ether (6), along with six known flavonoids, abyssinone-V-4‘-O-methyl ether (1), abyssinone-V (4), abyssinone-IV (5), sigmoidin E (7), 4‘-hydroxy-5,7-dimethoxyisoflavone (8), and alpinumisoflavone (9). Compounds 1 and 2, 4−7, and 9 inhibited PTP1B activity, with IC50 values ranging from 14.8 ± 1.1 to 39.7 ± 2.5 μM. On the basis of the data obtained, flavanones and chalcones with isoprenyl groups may be considered as a new class of PTP1B inhibitors.