RESUMO
Hyperuralones C-H (1-6), six new 1,9-seco-bicyclic polyprenylated acylphloroglucinols (1,9-seco-BPAPs) derived from the normal polyprenylated acylphloroglucinols with a bicyclo[3.3.1]nonane-2,4,9-trione core, together with six known analogues, were isolated from the aerial parts of Hypericum uralum. The structures of 1-6 were elucidated on the basis of the interpretation of NMR and MS spectroscopic data. The structure of attenuatumione B, a known compound isolated from H. attenuatum, was revised to that of a 1,9-seco-BPAP by NMR spectroscopic analysis and previous biomimetic synthesis methods. The inhibitory activities of these isolates on acetylcholinesterase were tested, and compounds 1 and 2 exhibited moderate activities with IC50 values of 9.6 and 7.1 µM, respectively.
Assuntos
Inibidores da Colinesterase/isolamento & purificação , Hypericum/química , Floroglucinol/análogos & derivados , Floroglucinol/isolamento & purificação , Acetilcolinesterase/efeitos dos fármacos , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Floroglucinol/químicaRESUMO
Nine new polyprenylated acylphloroglucinol derivatives, hypercohins B-J (1-9), and nine known analogues were isolated from the aerial parts of Hypericum cohaerens. The structures of 1-9 were elucidated based on spectroscopic analysis, and the absolute configuration of 1 was confirmed by X-ray crystallographic analysis. The inhibitory activities of these isolates on acetylcholinesterase and five human tumor cell lines were tested, and hypercohins B-D (1-3) exhibited moderate inhibitory activity (IC50 5.8-17.9 µM) against the tested tumor cell lines.
Assuntos
Antineoplásicos Fitogênicos , Medicamentos de Ervas Chinesas , Hypericum/química , Floroglucinol , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Inibidores da Colinesterase/química , Inibidores da Colinesterase/isolamento & purificação , Inibidores da Colinesterase/farmacologia , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Células HL-60 , Humanos , Concentração Inibidora 50 , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Floroglucinol/análogos & derivados , Floroglucinol/química , Floroglucinol/isolamento & purificação , Floroglucinol/farmacologiaRESUMO
Diabetes is an urgent health issue characterized by ethnic and regional variations, and is inseparable from the different dietary habits. It is worthy to note that the incidence of diabetes in Bai nationality has been reported to be much lower than Han in China. As a daily vegetable of Bai, the phytochemical and antidiabetic study of Ottelia acuminata var. acuminata had not been carried out. In this study, 41 metabolites with diverse diarylheptanoid (six new ones, Otteacumienes A-F), flavone, sesquiterpenoid, coumarin, lignan, polyacetylene, and alkaloid skeletons were characterized from O. acuminata var. acuminata. Among them, the racemic nature of 3 was characterized by chiral resolution and calculated ECD methods. The biological study revealed diarylheptanoids showed significant α-glucosidase inhibitory activities with 5 as the most effective one (60-fold stronger than acarbose). Molecular docking studies indicated that these structures have different binding cavities with acarbose. This study demonstrated that O. acuminata var. acuminata might correlated with the low incidence diabetes of Bai and the diarylheptanoids may have potential therapeutic value for diabetes mellitus.
RESUMO
6α-Hydroxylup-20(29)-en-3-on-28-oic acid (1), a natural triterpenoid, was found to possess the ability in a dose-dependent manner inhibiting hormone-induced adipocyte differentiation in 3T3-L1 preadipocytes, and restoring glucose consuming ability in dexamethasone (DXM)-induced insulin resistant 3T3-L1 adipocytes. Compound 1 was also found to ameliorate DXM-induced adipocyte dysfunction in lipolysis and adipokine secretion. Mechanistic studies revealed that 1 inhibited adipocyte differentiation in 3T3-L1 preadipocytes via down-regulating hormone-stimulated gene transcription of peroxisome proliferator-activated receptor γ and CCAAT-enhancer-binding protein alpha which are key factors in lipogenesis, and restored DXM-impaired glucose consuming ability in differentiated 3T3-L1 adipocytes via repairing insulin signaling pathway and activating down-stream signaling transduction by phosphorylation of signaling molecules PI3K/p85, Akt2 and AS160, thus leading to increased translocation of glucose transporter type 4 and transportation of glucose.
RESUMO
ABSTRACT: Four new polycyclic polyprenylated acylphloroglucinol type metabolites, hypercohones D-G (1-4), along with four known analogues (5-8), were isolated from the aerial parts of Hypericum cohaerens. The structures of these isolates were elucidated by extensive spectroscopic methods. The inhibitory activities of these isolates against five human cancer cell lines in vitro were also tested.
RESUMO
ABSTRACT: A new stigmasterol type natural product, viburodorol A (1), along with eleven known sterols and terpenoids (2-12), were isolated from the aerial parts of Viburnum odoratissimum. The structure of 1 was elucidated on the basis of comprehensive spectroscopic analysis. It's noteworthy that compound 2, the major constituent of this plant, can significantly stimulate glucose absorption in insulin resistant HepG2 cells without affecting cell viability. Furthermore, this compound can also restore the glucose absorption in DXMS-induced insulin resistant 3T3-L1 cells.
RESUMO
Hyperuralone A (1), a polycyclic polyprenylated acylphloroglucinol possessing an unprecedented tetracyclo-[5.3.1.1(4,9).0(4,11)]-dodecane core, was characterized from Hypericum uralum together with hyperuralone B (2), a congener with another complex caged skeleton. Their structures were determined by extensive spectroscopic analysis and ECD calculations. A plausible biosynthetic pathway of their intriguing architectures via intramolecular Diels-Alder reactions was also proposed. Compound 1 exhibited obviously cytotoxic activities against five human cancer cell lines in vitro (IC50 4.6-14.4 µM).
Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Hypericum/química , Floroglucinol/análogos & derivados , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Humanos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Floroglucinol/química , Floroglucinol/isolamento & purificação , Floroglucinol/farmacologiaRESUMO
ABSTRACT: Medicinal plants have a long history of use in China to treat diabetic symptoms. Ancient Chinese medical manuscripts and ethnobotanical surveys document plant remedies that continue to be actively used in China for the treatment of diabetic symptoms. Based on a systematic ancient Chinese medical manuscripts review in combination with ethnobotanical survey, 16 medicinal plants for the traditional treatment of diabetic symptoms were identified for the evaluation of anti-insulin resistance bioactivity. The biological activity of 16 medicinal plants was tested on dexamethasone (DXMS)-induced insulin resistant HepG2 cells. The result shows that 11 of the 16 medicinal plants enhanced glucose uptake of DXMS-induced insulin resistant HepG2 cells, thereby demonstrating their ability to increase insulin sensitivity, other five medicinal plants including Astragalus membranaceus were found ineffective. The study shows that ancient Chinese medical manuscripts and ethnobotanical surveys on plants for the prevention and treatment of diabetic symptoms provide a promising knowledge base for drug discovery to mitigate the global diabetes epidemic.