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1.
Fitoterapia ; 164: 105350, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36375687

RESUMO

Croton kongensis Gagnepain. belongs to the genus Croton, the Euphorbiaceae family, mainly distributed in Hainan and southern Yunnan, China. The aim of present study was to acquire secondary metabolites of the ethanol extract obtained from the leaves and twigs of C. kongensis. Three new abietane-type diterpenoids, crokongenolides A-C (1-3), together with seven known diterpenoids (4-10), were isolated from the leaves and twigs of C. kongensis. The structures of the new compounds were determined by extensive spectroscopic methods (1D and 2D NMR, IR, and HRESIMS), and their absolute configurations were confirmed by single-crystal X-ray diffraction analysis or electronic circular dichroism (ECD) calculations. The absolute configuration of 4 was determined for the first time by single-crystal X-ray diffraction analysis with Cu-Kα irradiation. Some compounds were evaluated for their antimicrobial properties by assessing their inhibitory effects on Staphylococcus aureus, Candida albicans, and Escherichia coli. Compound 10 showed significant antimicrobial activity against S. aureus with MIC value of 1.56 µg/ml.


Assuntos
Anti-Infecciosos , Croton , Diterpenos , Croton/química , Staphylococcus aureus , Estrutura Molecular , China , Folhas de Planta/química
2.
Phytochemistry ; 205: 113501, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36343681

RESUMO

Salvia has been regarded as a beneficial healing herb in ancient Egypt, Rome and Greece, and is listed as an official medicine in the pharmacopoeias of many countries worldwide. Currently, Salvia is widely used to flavor and preserve food. Here, two undescribed norabietane-type diterpenoids, sadigitaloides A and B, two undescribed germacrane-type sesquiterpenoids, sadigitaloides C and D, five undescribed guaiane-type sesquiterpenoid lactones, sadigitaloides E-I, two undescribed noreudesmane-type sesquiterpenoids, sadigitaloides J and K, one known diterpenoid, three known sesquiterpenoids, and three other types of known compounds were isolated from the 95% ethanol extract of the whole plants of Salvia digitaloides. Their structures and absolute configurations were characterized using 1D and 2D NMR spectroscopic techniques, electronic circular dichroism (ECD) calculations, HRESIMS experiments, and single-crystal X-ray diffraction analysis. Some compounds were evaluated for their anti-inflammatory activities against lipopolysaccharide (LPS)-induced TNF-α production in rat macrophage NR8383 cells. Sadigitaloide A showed noticeable anti-inflammatory activity at a concentration of 100.0 µM. At a concentration of 60 µM, sadigitaloide B exhibited better protection of dopaminergic neurons than the positive control n-butylidenephthalide in the Caenorhabditis elegans model injured by 6-OHDA. The phytotoxic activities of some compounds were attributed to considerable inhibitory effects on the growth of the roots and hypocotyls of Raphanus sativus L seedlings, especially cis, trans-abscisic acid, whose inhibition rates were much higher than those of glyphosate at concentrations ranging from 50 to 400 ppm. These results indicated that abietane-type diterpenoids possessed excellent anti-inflammatory and neuroprotective activities and further suggested that the low-molecular-weight compounds exhibited outstanding phytotoxic activities.


Assuntos
Salvia , Animais , Ratos , Anti-Inflamatórios , Grécia
3.
Nat Prod Res ; : 1-7, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36260069

RESUMO

A new clerodane diterpenoid, crotolanin A (1), along with three known clerodane diterpenoids, crotoeurin B (2), teucvidin (3) and teucvin (4), was isolated from the ethanol extract of the leaves and twigs of Croton lachnocarpus Benth. Their structures were identified by extensive NMR spectroscopic and HRESIMS analyses. The dopaminergic neuroprotective activity of compounds 1-4 was tested by using transgenic Caenorhabditis elegans pathological model. Compound 2 alleviated dopaminergic neuron degeneration of worms induced by 6-hydroxydopamine (6-OHDA) that represented a potential therapy for Parkinson's disease (PD).

4.
Front Chem ; 10: 911543, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35815214

RESUMO

One novel diterpenoid lactone named caesalpinbondin A (1) that possesses an unprecedented tetracyclic ring system in which a 6/6/5-fused tricyclic ring and a 4,5-dimethyldihydrofuran-2(3H)-one were connected by a C-C single bond comprising a 5-(naphtho [2,3-b]furan-7-yl)dihydrofuran-2(3H)-one moiety was isolated from the seeds of Caesalpinia bonduc. Its chemical structure was established by extensive spectroscopic methods, and its absolute configuration was further determined by single-crystal X-ray diffraction analysis and electronic circular dichroism calculation. The biological evaluation suggested that compound 1 demonstrated potent anti-Alzheimer's disease (AD) bioactivity, which could delay paralysis of transgenic AD Caenorhabditis elegans. A possible biogenetic pathway of 1 was also proposed.

5.
Fitoterapia ; 161: 105248, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35777590

RESUMO

Viticis Fructus, known as "Man-jing-zi", are the fruits of the traditional Chinese medicine Vitex trifolia Linn. and its variant Vitex trifolia Linn. var. simplicifolia. These fruits are used as folk medicines to treat various diseases. Although V. trifolia is useful for treating diabetes, the antidiabetic effect of its purified constituents is still under investigation. The phytochemical investigation on the ethanol extract of the fruits of V. trifolia yielded four new labdane diterpenoids vitetrolins A-D (1-4), together with seven (5-11) known analogs. The structures of these compounds were elucidated by spectroscopy techniques and the absolute configuration of 4 was determined by electronic circular dichroism (ECD) calculations. The isolated diterpenoids were evaluated for their α-glucosidase inhibitory activities. Compounds 5, 6, 8, and 9 exhibited moderate inhibitory activities against α-glucosidase with IC50 values ranging from 44.9 ± 6.1 to 70.5 ± 5.5 µM.


Assuntos
Diterpenos , Inibidores de Glicosídeo Hidrolases , Vitex , Diterpenos/farmacologia , Frutas/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Humanos , Estrutura Molecular , Vitex/química , alfa-Glucosidases
6.
Front Chem ; 10: 861278, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35419345

RESUMO

Croton yanhuii (Family Euphorbiaceae) is an annual aromatic plant endemic to Yunnan Province, China, which yields an aromatic, spicy oil used as a flavoring and fragrance. The aim of the present study was to acquire secondary metabolites from the leaves and twigs of C. yanhuii and to evaluate their cytotoxic activity. Five new diterpenoids, croyanhuins A-E (1-5), and one new C13 nor-isoprenoid, croyanhuin F (6), were isolated from the leaves and twigs of C. yanhuii. Their structures and absolute configurations were determined by extensive spectroscopic methods (1D and 2D NMR, IR, and HRESIMS) and confirmed by electronic circular dichroism (ECD) spectra or single-crystal X-ray diffraction analysis. Among the new terpenoids, compounds 1 and 3 inhibited cell proliferation and viability in a dose- and time-dependent manner, whereas both induced cleavage of either caspase-3 or PARP-1 in the SW480 cell line. Additionally, we observed that Z-YVAD-FMK and Z-VAD-FMK, two caspase inhibitors, inhibited the compound-dependent cell viability loss, suggesting that either of them can induce pyroptosis and caspase-dependent apoptosis. These biological assay results revealed that compounds 1 and 3 induce different kinds of programmed cell death in SW480 cells.

7.
Int Ophthalmol ; 42(8): 2525-2531, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35381898

RESUMO

PURPOSE: To evaluate the repeatability of wavefront aberration measurements and the correlation between corneal aberration and pupil size in normal eyes using a wavefront-based autorefractor (i.ProfilerPlus; Carl Zeiss Vision, Germany). METHODS: A prospective cross-sectional study. Wavefront aberrations, including spherical aberration (SA) (Z40), coma (Z3-1, Z31), trefoil (Z3-3, Z33) and total higher-order aberrations (tHOA), were measured at different pupil diameters. The repeatability was evaluated using one-way ANOVA method, and statistical indicators including within-subject standard deviation (Sw), test-retest repeatability (TRT), and intra-class correlation coefficient (ICC). The correlations between corneal aberrations and pupil sizes were evaluated by Pearson correlation analysis. RESULTS: A total of 96 healthy young volunteers were enrolled. Corneal and ocular higher-order aberrations (HOA) measured by i.Profiler showed Sw < 0.01 µm, TRT < 0.10 µm, ICC > 0.90. There was a linear positive correlation between the corneal HOA and pupil size. The correlation coefficient between SA and tHOA was the largest (r = 0.996, P < 0.001). CONCLUSIONS: The measurements of wavefront aberrations by i.Profiler are highly repeatable. Corneal HOA was significantly dependent on pupil size. SA was the most influential aberration for visual quality in this study.


Assuntos
Aberrações de Frente de Onda da Córnea , Córnea , Topografia da Córnea/métodos , Aberrações de Frente de Onda da Córnea/diagnóstico , Estudos Transversais , Humanos , Estudos Prospectivos , Refração Ocular , Transtornos da Visão
8.
Front Psychol ; 10: 1803, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31447740

RESUMO

Employee innovation is the cornerstone of the organization, and the motivation for employee innovative behavior largely depends on the leadership style of the leader. With the economic development of society, the traditional authoritative style of leadership can no longer adapt to the psychological characteristics of employees, who use new-era work concepts, techniques, and social rules (hereafter, new generation employees). Inclusive leadership is based on the concept of "fully inclusive and equitable" in traditional Chinese culture, and it can adapt to the independent needs of new generation employees. At present, the research on the relationship between the traditional leadership style and employee innovative behavior is relatively extensive, but there is little research on the relationship between inclusive leadership style and employee innovative behavior, and this needs further exploration. This paper takes new generation employees as the sample and uses psychological capital as an intermediary variable to explore the influence of inclusive leadership style on the innovative behaviors of new generation employees. We found that inclusive leadership is significantly and positively related to new generation employees' innovative behavior. Theoretical and practical implications are discussed.

9.
Nat Commun ; 8: 14335, 2017 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-28181498

RESUMO

Acute hormone secretion triggered by G protein-coupled receptor (GPCR) activation underlies many fundamental physiological processes. GPCR signalling is negatively regulated by ß-arrestins, adaptor molecules that also activate different intracellular signalling pathways. Here we reveal that TRV120027, a ß-arrestin-1-biased agonist of the angiotensin II receptor type 1 (AT1R), stimulates acute catecholamine secretion through coupling with the transient receptor potential cation channel subfamily C 3 (TRPC3). We show that TRV120027 promotes the recruitment of TRPC3 or phosphoinositide-specific phospholipase C (PLCγ) to the AT1R-ß-arrestin-1 signalling complex. Replacing the C-terminal region of ß-arrestin-1 with its counterpart on ß-arrestin-2 or using a specific TAT-P1 peptide to block the interaction between ß-arrestin-1 and PLCγ abolishes TRV120027-induced TRPC3 activation. Taken together, our results show that the GPCR-arrestin complex initiates non-desensitized signalling at the plasma membrane by coupling with ion channels. This fast communication pathway might be a common mechanism of several cellular processes.


Assuntos
Catecolaminas/metabolismo , Receptor Tipo 1 de Angiotensina/agonistas , Canais de Cátion TRPC/metabolismo , beta-Arrestina 1/metabolismo , beta-Arrestina 2/metabolismo , Animais , Cálcio/metabolismo , Estrenos/farmacologia , Células HEK293 , Humanos , Ligantes , Camundongos Knockout , Oligopeptídeos/farmacologia , Fosfolipase C gama/metabolismo , Pirrolidinonas/farmacologia , Receptor Tipo 1 de Angiotensina/metabolismo , Transdução de Sinais/efeitos dos fármacos , beta-Arrestina 1/química
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