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1.
Fitoterapia ; 176: 106015, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38762075

RESUMO

Five dihydrophenanthropyrans (1-5) were isolated from the pseudobulbs of Pholidota chinensis, among which 1,3-di(4'-hydroxybenzy)-imbricatin (3) was isolated from the nature for the first time. Their structures were elucidated and established through various spectroscopic methods. These compounds exhibited a potent inhibition effect on both N-formyl-methionyl-leucyl-phenylalanine (fMLF)-induced superoxide anion generation and elastase release with IC50 values ranging from 0.23 to 7.63 µM. Furthermore, dihydrophenanthropyrans (1-3) also demonstrated a dose-dependent reactive oxygen species (ROS) scavenging effect. In addition, dihydrophenanthropyrans (2-3) exhibited a dose-dependent reduction in the intracellular Ca2+ concentration ([Ca2+]i) in fMLF-activated human neutrophils. Moreover, dihydrophenanthropyrans (1-3) selectively inhibited the phosphorylation of c-Jun N-terminal kinases (JNKs) and p38, while only dihydrophenanthropyran (1) inhibited the phosphorylation of extracellular signal-regulated kinases (ERKs) in fMLF-activated human neutrophils. Notably, dihydrophenanthropyrans (1-3) did not affect protein kinase B (AKT) activity in these cells. These findings highlight the potent anti-inflammatory capabilities of dihydrophenanthropyrans, manifested through their ability to inhibit superoxide anion generation, suppress elastase release, and selectively modulate key signaling pathways in human neutrophils. This suggests that dihydrophenanthropyrans hold significant promise as therapeutic agents for conditions associated with neutrophil-mediated inflammation.

2.
Int J Mol Sci ; 24(14)2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37511036

RESUMO

A previous 1H-NMR method allowed the quantification of ephedrine alkaloids; however, there were some disadvantages. The cyclized derivatives resulted from the impurities of diethyl ether were identified and benzene was selected as the better extraction solvent. The locations of ephedrine alkaloids were confirmed with 2D NMR. Therefore, a specific 1H-NMR method has been modified for the quantification of ephedrine alkaloids. Accordingly, twenty Ephedrae Herba samples could be classified into three classes: (I) E. sinica-like species; (II) E. intermedia-like species; (III) others (lower alkaloid contents). The results indicated that ephedrine and pseudoephedrine are the major alkaloids in Ephedra plants, but the concentrations vary greatly determined by the plant species and the collection locations.


Assuntos
Alcaloides , Ephedra , Efedrina , Espectroscopia de Prótons por Ressonância Magnética , Pseudoefedrina , Efedrina/análise , Pseudoefedrina/análise , Ephedra/química , Alcaloides/análise , Espectroscopia de Prótons por Ressonância Magnética/métodos
3.
J Nat Prod ; 86(6): 1437-1448, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37200063

RESUMO

Seven previously undescribed diterpenoids, tinocrisposides A-D (1-4) and borapetic acids A (5), B (6), and C (7), together with 16 known compounds, were isolated from the stem of Tinospora crispa (Menispermaceae). The structures of the new isolates were elucidated by spectroscopic and chemical methods. The ß-cell protective effect of the tested compounds was examined on insulin-secreting BRIN-BD11 cells under dexamethasone treatment. Diterpene glycosides 12, 14-16, and 18 presented a substantial protective effect on BRIN-BD11 cells treated with dexamethasone in a dose-dependent manner. Compounds 4 and 17 with two sugar moieties exhibited clear protective effects on ß-cells.


Assuntos
Diterpenos , Tinospora , Glicosídeos/farmacologia , Glicosídeos/química , Tinospora/química , Diterpenos/farmacologia , Dexametasona
4.
Phytochemistry ; 206: 113528, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36460139

RESUMO

Six previously undescribed components, bis(4-glycosyloxybenzyl) 2-isobutyltartrate derivatives (pholidotoside A-E) and phenolic glycoside (pholidotosin A), together with twenty known compounds were isolated from the pseudobulbs of Pholidota chinensis. Their structures and absolute configuration were elucidated and established through various spectroscopic and chemical methods. The anti-inflammatory potential of selected compounds was examined using a human neutrophil cell model activated by N-formyl-methionyl-leucyl-phenylalanine/cytochalasin B (fMLP/CB). Among these, dihydrophenanthrenes exhibited potent inhibitory effect on both superoxide anion generation and elastase release assays with IC50 values ranging from 0.41 ± 0.05 to 7.14 ± 0.30 µM.


Assuntos
Orchidaceae , Pangolins , Humanos , Animais , Superóxidos/farmacologia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Fenóis/farmacologia , Neutrófilos
5.
Antioxidants (Basel) ; 11(2)2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35204218

RESUMO

Seven new anthraquinones with rare 2-isopropyldihydrofuran (1-3) and 2,2-dimethylpyrano (4-7) moieties together with thirty-four known compounds were isolated from the extracts of whole Hedyotis diffusa plants. Their structures were elucidated and established by various spectroscopic and spectrometric analytical methods. Among these isolates, selected compounds were examined for their anti-inflammatory activity. The results showed that rare substituted anthraquinones displayed potent inhibitory activity with IC50 values ranging from 0.15 ± 0.01 to 5.52 ± 1.59 µM on the N-formyl-methionyl-leucyl-phenylalanine/cytochalasin B (fMLP/CB)-induced superoxide anion generation and elastase release cellular models. Meanwhile, the proposed drug target of the active anthraquinone was studied by computer modeling. The binding affinity between the anti-inflammatory anthraquinone and elastase was evaluated by molecular docking. These results provided the scientific insight into the medicinal values of Hedyotis diffusa and vision of development as lead compounds.

6.
Plant Physiol ; 188(1): 318-331, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-34618124

RESUMO

Petals of the monocot Phalaenopsis aphrodite (Orchidaceae) possess conical epidermal cells on their adaxial surfaces, and a large amount of cuticular wax is deposited on them to serve as a primary barrier against biotic and abiotic stresses. It has been widely reported that subgroup 9A members of the R2R3-MYB gene family, MIXTA and MIXTA-like in eudicots, act to regulate the differentiation of conical epidermal cells. However, the molecular pathways underlying conical epidermal cell development and cuticular wax biosynthesis in monocot petals remain unclear. Here, we characterized two subgroup 9A R2R3-MYB genes, PaMYB9A1 and PaMYB9A2 (PaMYB9A1/2), from P. aphrodite through the transient overexpression of their coding sequences and corresponding chimeric repressors in developing petals. We showed that PaMYB9A1/2 function to coordinate conical epidermal cell development and cuticular wax biosynthesis. In addition, we identified putative targets of PaMYB9A1/2 through comparative transcriptome analyses, revealing that PaMYB9A1/2 acts to regulate the expression of cell wall-associated and wax biosynthetic genes. Furthermore, a chemical composition analysis of cuticular wax showed that even-chain n-alkanes and odd-chain primary alcohols are the main chemical constituents of cuticular wax deposited on petals, which is inconsistent with the well-known biosynthetic pathways of cuticular wax, implying a distinct biosynthetic pathway occurring in P. aphrodite flowers. These results reveal that the function of subgroup 9A R2R3-MYB family genes in regulating the differentiation of epidermal cells is largely conserved in monocots and dicots. Furthermore, both PaMYB9A1/2 have evolved additional functions controlling the biosynthesis of cuticular wax.


Assuntos
Diferenciação Celular/genética , Proliferação de Células/genética , Orchidaceae/crescimento & desenvolvimento , Orchidaceae/genética , Orchidaceae/metabolismo , Epiderme Vegetal/genética , Epiderme Vegetal/metabolismo , Ceras/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Morfogênese/genética , Plantas Geneticamente Modificadas
7.
Pharmaceuticals (Basel) ; 14(9)2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34577615

RESUMO

Multidrug resistance (MDR), for which the mechanisms are not yet fully clear, is one of the major obstacles to cancer treatment. In recent years, signal transducer and activator of transcription 3 (STAT3) were found to be one of the important MDR mechanism pathways. Based on the previous research, zhankuic acid A, B, and C were found to have collateral sensitivity effects on MDR cancer cells, and MDR inhibitory activity of zhankuic acid methyl ester was found to be better than that of its acid. Therefore, we executed a systematic examination of the structure-activity relationship of zhankuic acid methyl ester derivatives to collateral sensitivity in MDR cancer cells. The results showed that compound 12 is the best in terms of chemoreversal activity, where the reversal fold was 692, and the IC50 value of paclitaxel combined with 10 µM compound 12 treatment was 1.69 nM in MDR KBvin cells. Among all the derivatives, methyl ester compounds were found to be better than their acids, and a detailed discussion of the structure-activity relationships of all of the derivatives is provided in this work. In addition, compounds 8, 12, and 26 were shown to influence the activation of STAT3 in KBvin cells, accounting for part of their chemoreversal effects. Our results may provide a new combined therapy with paclitaxel to treat multidrug-resistant cancers and provide a new therapy option for patients.

8.
Bioorg Chem ; 112: 104939, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33951534

RESUMO

Drug resistance of cancer cells stands for the major problem of the treatment failure for chemotherapy or target therapy. Overexpression of efflux pumps leading to multidrug resistance (MDR) is still an important issue needed to be solved. In the present study, Taiwanofungus salmoneus was selected as the topic and eleven undescribed constituents including four naphthoquinones salmonones A-D (1-4) and seven triterpenoids salmoneatins A-G (5-11), along with one chromanone (12) and two benzenoids (13 and 14) reported from the natural sources for the first time, as well as twenty-one known compounds were characterized. The structures of undescribed compounds were established by the spectroscopic and spectrometric analyses. In addition, the plausible biosynthetic mechanism of purified naphthoquinones was proposed and these compounds may be the excellent chemotaxonomic markers. Moreover, the isolates were evaluated for their P-gp inhibitory effects and the results showed that most of the examined compounds were effective. Among the tested compounds, 5, 10, 2,3-dimethoxy-5-(2',5'-dimethoxy-3',4'-methylenedioxyphenyl)-7-methyl-[1,4]naphthoquinone, zhankuic acid A methyl ester, and camphoratin F can reverse the resistance of paclitaxel or vincristine with the reversal folds in the range of 51093.3 and 259.5. These experimental data would initiate the possible development of Taiwanofungus salmoneus for the cancer therapy in the future.


Assuntos
Antineoplásicos/farmacologia , Carpóforos/química , Naftoquinonas/farmacologia , Polyporales/química , Triterpenos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Naftoquinonas/química , Naftoquinonas/isolamento & purificação , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/isolamento & purificação , Células Tumorais Cultivadas
9.
Molecules ; 26(6)2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33805790

RESUMO

A highly specific and sensitive proton nuclear magnetic resonance (1H-NMR) method has been developed for the quantification of ephedrine alkaloid derivatives in Ephedra herbal commercial prescriptions. At the region of δ 4.0 to 5.0 ppm in the 1H NMR spectrum, the characteristic signals are separated well from each other, and six analogues in total, methylephedrine (ME), ephedrine (EP), norephedrine (NE), norpseudoephedrine (NP), pseudoephedrine (PE), and methylpseudoephedrine (MP) could be identified. The quantities of these compounds are calculated by the relative ratio of the integral values of the target peak for each compound to the known concentrations of the internal standard anthracene. The present method allows for a rapid and simple quantification of ephedrine alkaloid derivatives in Ephedra-related commercial prescriptions without any preliminary purification steps and standard compounds, and accordingly it can be a powerful tool to verify different Ephedra species. In comparison to conventional chromatographic methods, the advantages of this method include the fact that no standard compounds are required, the quantification can be directly performed on the crude extracts, a better selectivity for various ephedrine alkaloid derivatives, and the fact that a very significant time-gain may be achieved.


Assuntos
Alcaloides/análise , Ephedra/química , Efedrina/análogos & derivados , Efedrina/análise , Ephedra/classificação , Estudos de Viabilidade , Humanos , Limite de Detecção , Espectroscopia de Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/estatística & dados numéricos , Medicina Tradicional Chinesa , Fenilpropanolamina/análise , Preparações de Plantas/química , Pseudoefedrina/análise , Especificidade da Espécie
10.
Bioorg Chem ; 108: 104562, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33358389

RESUMO

Twelve undescribed lanostane-type triterpenes, and twenty-two known triterpenes were isolated and identified from a medicinal bracket fungus Fomitopsis pinicola (Sw.) P. Karst. The structures of these compounds were determined by spectroscopic and spectrometric analyses. The antiinflammatory potential of thirty-two triterpene compounds was evaluated using neutrophils as an assay model, and pinicolasin J was the most potent inhibitor of superoxide anion generation and elastase release, with IC50 values of 1.81 ± 0.44 and 2.50 ± 0.64 µM, respectively. This study provides scientific insight into the nutritional supplement value and medicinal development of Fomitopsis pinicola.


Assuntos
Anti-Inflamatórios/farmacologia , Coriolaceae/química , Inibidores Enzimáticos/farmacologia , Carpóforos/química , Elastase Pancreática/antagonistas & inibidores , Triterpenos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Humanos , Estrutura Molecular , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Elastase Pancreática/metabolismo , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/isolamento & purificação
11.
Nat Prod Res ; 35(1): 17-24, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31135226

RESUMO

A new dimeric quaternary protoberberine alkaloid, bispalmatrubine (1), and thirteen known compounds (2-14) were purified from the tubers of Tinospora dentata. Their structures were determined by spectroscopic and spectrometric analytical methods. Among the isolates, eight compounds were examined for their in vitro anti-inflammatory potential and several tested alkaloids displayed moderate inhibitory effects of N-formyl-methionyl-leucyl-phenylalanine/cytochalasin B (fMLP/CB)-induced superoxide anion generation and elastase release.


Assuntos
Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Tinospora/química , Alcaloides/química , Alcaloides/farmacologia , Alcaloides de Berberina/química , Citocalasina B/farmacologia , Humanos , Estrutura Molecular , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Elastase Pancreática/metabolismo , Tubérculos/química , Plantas Medicinais/química , Superóxidos/metabolismo
12.
Molecules ; 25(22)2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33213112

RESUMO

This study investigates the application of the paramagnetic shift reagent tris(dipivaloylmethanato)-europium(III) in NMR spectral studies of permethoxyacridone alkaloids (1-3) and pyranoacridone alkaloids (4-6). The induced chemical shifts (∆δ) of all protons were observed for the same molecule, and were compared to deduce the positions resulting from the distance nearby the Eu(dpm)3. Assignment of the H-2, H-4 and H-8 of polysubstituted acridones could be distinguished based on the least-squares method of lanthanide-induced shifts plotted against the mole ratios of Eu(dpm)3 to the substrate. The developed method is not only potentially useful for determining the planar structures of polysubstituted compounds, such as acridones, anthraquinones, xanthones, flavonoids, and phenanthrenes, but also applicable for their stereochemistry.


Assuntos
Acridonas/química , Alcaloides/química , Elementos da Série dos Lantanídeos/química , Espectroscopia de Prótons por Ressonância Magnética , Európio/química
13.
Bioorg Med Chem Lett ; 30(13): 127224, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32359855

RESUMO

Four new sesquiterpenes (1-4), one new alkaloid (5), and one new benzenoid glycoside (6) were characterized from Lindera aggregata, and their structures were elucidated according to their spectrometric analytical data. Among these isolates, 3 and 4 were constructed as possessing unprecedented carbon skeletons from the natural source. Some of these purified constituents were examined for their anti-inflammatory bioactivity. Among the tested compounds, linderaggredin C (3), (+)-N-methyllaurotetanine, and (+)-isoboldine displayed the significant inhibition of superoxide anion generation in human neutrophils with IC50 values of 7.45 ± 0.74, 8.36 ± 0.11, and 5.81 ± 0.59 µM, respectively.


Assuntos
Anti-Inflamatórios/farmacologia , Lindera/química , Sesquiterpenos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Humanos , Estrutura Molecular , Neutrófilos/efeitos dos fármacos , Elastase Pancreática/metabolismo , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Superóxidos/metabolismo
14.
Fitoterapia ; 139: 104376, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31629048

RESUMO

Ten compounds were isolated from the root bark of Bombax malabarica, including two new compounds, bombamalin (1) and 3,4,5-trimethoxyphenol-1-[ß-xylopyranosyl-(1 → 2)]-ß-glucopyranoside (3), and shorealactone (4), a rare dehydroascorbic acid fused l-ε-viniferin. Compound 1 is an unusual bissesquiterpene, containing a 1,4-dioxene ring formed by fusing isohemigossypol with ent-cadinen-2-one. Their structures were elucidated by extensive spectroscopic analysis. This chemical reinvestigation is of value for chemotaxonomy of the Bombax genus, in particular the finding of the unusual 1 and rare 4. Among the isolates, shorealactone (4), l-epicatechin 5-O-ß-D-xyloside (5), and 2-C-[ß-D-apiosyl-(1 → 6)]- ß-D-glucosyl]-1,3,6-trihydroxy-7-methoxyxanthone (6) displayed some inhibition against α-glucosidase with IC50 values of 224, 345, and 285 µM, respectively.


Assuntos
Bombax/química , Compostos Fitoquímicos/isolamento & purificação , Casca de Planta/química , Raízes de Plantas/química , Inibidores de Glicosídeo Hidrolases , Sesquiterpenos/isolamento & purificação , Taiwan
15.
Molecules ; 24(7)2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30965630

RESUMO

Seventy-three compounds were identified from the methanol extract of V. luteola, and among these, three new (1⁻3) were characterized by spectroscopic and mass spectrometric analyses. The isolated constituents were assessed for anti-inflammatory potential evaluation, and several purified principles exhibited significant superoxide anion and elastase inhibitory effects.


Assuntos
Anti-Inflamatórios/farmacologia , Compostos Fitoquímicos/farmacologia , Vigna/química , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Citocalasina B/efeitos adversos , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Elastase Pancreática/antagonistas & inibidores , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Superóxidos/antagonistas & inibidores
16.
RSC Adv ; 9(38): 21616-21625, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35518857

RESUMO

The Machilus genus (Lauraceae) had been extensively utilized in folk medicine due to its broad range of bioactivities. In the present study, a series of chromatographic separations of the methanol extract of stems of M. philippinensis led to the identification of thirty eight compounds totally. Among these, biscinnamophilin (1), machilupins A-C (2-4), machilutone A (5), and machilusoxide A (6) were new compounds reported for the first time. In addition, 5 was characterized with a unprecedented carbon skeleton. Other known compounds, including the major compounds cinnamophilin (7) and meso-dihydroguaiaretic acid (8), are identified by comparison of their physical and spectroscopic data with reported values. One of the reported compounds, cinnamophilin A (10), should be revised as dehydroguaiaretic acid (9) after careful comparison of all the 1H and 13C NMR data. Moreover, the neuroprotective activity of cinnamophilin (7) was examined in a primary cortical neuron culture and the results indicated that 7 was effective against glutamate induced excitotoxicity.

17.
RSC Adv ; 9(59): 34184-34195, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-35530004

RESUMO

Twelve undescribed sesquiterpenoids, fomitopins A-L (1-12), were isolated via bioassay-guided purification from the bracket fungus Fomitopsis pinicola (Sw.) P. Karst, and this fungus have been reported to exhibit anti-microbial and anti-inflammatory activities. The structures of 1-12 were elucidated by spectroscopic and spectrometric analyses and their absolute configurations were further confirmed by ECD simulations. Ten isolated compounds were evaluated for their anti-inflammatory potential and compound 11 exhibited the most significant inhibition of superoxide anion generation and elastase release with IC50 values of 0.81 ± 0.15 and 0.74 ± 0.12 µM. These newly purified sesquiterpenoids could be potential candidates for further anti-inflammatory studies.

18.
Molecules ; 23(10)2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30301176

RESUMO

Fifty-seven compounds were purified from the stems of Tinospora sinensis, including three new compounds characterized as a lignan (1), a pyrrole alkaloid (11), and a benzenoid (17), respectively. Their structures were elucidated and established by various spectroscopic and spectrometric analytical methods. Among the isolates, fifteen compounds were examined for their anti-inflammatory potential in vitro. The results showed that several compounds displayed moderate inhibition of N-formyl-methionyl-leucyl-phenylalanine/cytochalasin B (fMLP/CB)-induced superoxide anion generation and elastase release.


Assuntos
Alcaloides/farmacologia , Lignanas/farmacologia , Elastase Pancreática/metabolismo , Pirróis/farmacologia , Alcaloides/química , Citocalasina B/antagonistas & inibidores , Citocalasina B/toxicidade , Humanos , Lignanas/química , Estrutura Molecular , Neutrófilos/efeitos dos fármacos , Neutrófilos/enzimologia , Elastase Pancreática/biossíntese , Elastase Pancreática/efeitos dos fármacos , Caules de Planta/química , Pirróis/química , Superóxidos/antagonistas & inibidores , Superóxidos/toxicidade , Tinospora/química
19.
Phytomedicine ; 20(8-9): 667-75, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23523259

RESUMO

AIM: This study explores the hypoglycemic effects of borapetoside A, the most active principle among three major diterpenoids (borapetosides A, B, and C) isolated from ethanol extract of Tinospora crispa vines. METHODS: We employed mouse mitogenic C2C12 and hepatocellular carcinoma Hep3B cells in this study. Furthermore, the mice were divided into three groups, including streptozotocin-induced type 1 diabetes mellitus, diet-induced type 2 diabetes mellitus, and normal control. The mice in each group were treated with assigned vehicle control, borapetoside A, or other active agents. RESULTS: Borapetoside A was shown to increase the glycogen content and decrease the plasma glucose concentration in a concentration or dose-dependent manner in vitro and in vivo. The hypoglycemic effects in the normal mice and the mice with type 2 diabetes mellitus were associated with the increases of the plasma insulin levels; whereas, the insulin levels remained unchanged in the mice with type 1 diabetes mellitus. Borapetoside A not only attenuated the elevation of plasma glucose induced by an intraperitoneal glucose tolerance test, but also increased the glycogen synthesis of IL-6 treated C2C12 cells. Moreover, the elevated protein expression levels of phosphoenolpyruvate carboxykinase were reversed after borapetoside A treatment twice a day for 7 days. CONCLUSIONS: The hypoglycemic effects of borapetoside A were mediated through both the insulin-dependent and the insulin-independent pathways. Furthermore, borapetoside A was shown to increase the glucose utilization in peripheral tissues, to reduce the hepatic gluconeogenesis, and to activate the insulin signaling pathway; they thereby contributed to the lowering of the plasma glucose. Comparison of the structures of three borapetosides suggests clearly that the C-8 stereochemistry plays a key role in hypoglycemic effect since the active borapetoside A and C possess 8R-chirality but the inactive borapetoside B possess 8S-chirality. The location of glycoside at C-3 for borapetoside A but C-6 for borapetoside C and the formation of lactone between C-4 and C-6 for borapetoside A, could account for the different potency in hypoglycemic action for these two compounds.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diterpenos/uso terapêutico , Glucosídeos/uso terapêutico , Hipoglicemiantes/uso terapêutico , Fitoterapia , Extratos Vegetais/química , Tinospora/química , Animais , Glicemia/efeitos dos fármacos , Linhagem Celular , Diabetes Mellitus Tipo 2/tratamento farmacológico , Modelos Animais de Doenças , Diterpenos/química , Diterpenos/isolamento & purificação , Gluconeogênese/efeitos dos fármacos , Glucose/metabolismo , Glucosídeos/química , Glucosídeos/isolamento & purificação , Glicogênio/análise , Glicogênio/metabolismo , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Insulina/sangue , Interleucina-6/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Músculos/efeitos dos fármacos , Músculos/metabolismo , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo , Extratos Vegetais/isolamento & purificação , Plantas Medicinais/química , Transdução de Sinais/efeitos dos fármacos
20.
Phytomedicine ; 19(8-9): 719-24, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22579212

RESUMO

Diabetes mellitus (DM) often leads to disability from vascular complications and neurological complications. Tinospora crispa has been widely used in Asia and Africa as a remedy for diabetes and other diseases. In this study, we investigated the hypoglycemic actions of borapetoside C isolated from T. crispa, and the mechanisms underlying its actions. Acute treatment with borapetoside C (5mg/kg, i.p.) attenuated the elevated plasma glucose induced by oral glucose in normal and type 2 DM (T2DM) mice. Compared to the effect of injected insulin (0.5 IU/kg), borapetoside C caused a more prominent increase of glycogen content in skeletal muscle of T2DM mice, but a less increase in type 1 DM (T1DM) mice. Combined treatment of a low dose borapetoside C (0.1mg/kg, i.p.) plus insulin enhanced insulin-induced lowering of the plasma glucose level and insulin-induced increase of muscle glycogen content. Continuous treatment with 5mg/kg borapetoside C (twice daily) for 7 days increased phosphorylation of insulin receptor (IR) and protein kinase B (Akt) as well as the expression of glucose transporter-2 (GLUT2) in T1DM mice. Combined treatment of a low dose borapetoside C (0.1mg/kg, twice daily) plus insulin for 7 days enhanced insulin-induced IR and Akt phosphorylation and GLUT2 expression in the liver of T1DM mice. This study proved that borapetoside C can increase glucose utilization, delayed the development of insulin resistance and enhanced insulin sensitivity. The activation of IR-Akt-GLUT2 expression and the enhancement of insulin sensitivity may contribute to the hypoglycemic action of borapetoside C in diabetic mice.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Diterpenos/farmacologia , Hipoglicemiantes/farmacologia , Resistência à Insulina , Tinospora/química , Animais , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Quimioterapia Combinada , Teste de Tolerância a Glucose , Transportador de Glucose Tipo 2/metabolismo , Glicogênio/metabolismo , Insulina/metabolismo , Insulina/farmacologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Fosforilação , Plantas Medicinais/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor de Insulina/metabolismo , Transdução de Sinais
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