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1.
Front Cell Infect Microbiol ; 13: 1257817, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37928189

RESUMO

Helicobacter pylori, a gram-negative microaerophilic pathogen, causes several upper gastrointestinal diseases, such as chronic gastritis, peptic ulcer disease, and gastric cancer. For the diseases listed above, H. pylori has different pathogenic mechanisms, including colonization and virulence factor expression. It is essential to make accurate diagnoses and provide patients with effective treatment to achieve positive clinical outcomes. Detection of H. pylori can be accomplished invasively and noninvasively, with both having advantages and limitations. To enhance therapeutic outcomes, novel therapeutic regimens, as well as adjunctive therapies with probiotics and traditional Chinese medicine, have been attempted along with traditional empiric treatments, such as triple and bismuth quadruple therapies. An H. pylori infection, however, is difficult to eradicate during treatment owing to bacterial resistance, and there is no commonly available preventive vaccine. The purpose of this review is to provide an overview of our understanding of H. pylori infections and to highlight current treatment and diagnostic options.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/tratamento farmacológico , Antibacterianos/uso terapêutico , Quimioterapia Combinada , Bismuto/uso terapêutico
2.
Biomed Pharmacother ; 165: 115100, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37418977

RESUMO

The use of oral agents that can modify the gut microbiota (GM) could be a novel preventative or therapeutic option for Parkinson's disease (PD). Maslinic acid (MA), a pentacyclic triterpene acid with GM-dependent biological activities when it is taken orally, has not yet been reported to be effective against PD. The present study found both low and high dose MA treatment significantly prevented dopaminergic neuronal loss in a classical chronic PD mouse model by ameliorating motor functions and improving tyrosine hydroxylase expressions in the substantia nigra pars compacta (SNpc) and increasing dopamine and its metabolite homovanillic acid levels in the striatum. However, the effects of MA in PD mice were not dose-responsive, since similar beneficial effects for low and high doses of MA were observed. Further mechanism studies indicated that low dose MA administration favored probiotic bacterial growth in PD mice, which helped to increase striatal serotonin, 5-hydroxyindole acetic acid, and γ-aminobutyric acid levels. High dose MA treatment did not influence GM composition in PD mice but significantly inhibited neuroinflammation as indicated by reduced levels of tumor necrosis factor alpha and interleukin 1ß in the SNpc; moreover, these effects were mainly mediated by microbially-derived acetic acid in the colon. In conclusion, oral MA at different doses protected against PD via distinct mechanisms related to GM. Nevertheless, our study lacked in-depth investigations of the underlying mechanisms involved; future studies will be designed to further delineate the signaling pathways involved in the interactive actions between different doses of MA and GM.


Assuntos
Microbioma Gastrointestinal , Doença de Parkinson , Camundongos , Animais , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/prevenção & controle , Doença de Parkinson/metabolismo , Substância Negra , Dopamina/metabolismo , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo
3.
Front Microbiol ; 14: 1208157, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37389333

RESUMO

Resistance of Helicobacter pylori (H. pylori) to antibiotics has reached alarming levels worldwide, and the efficacy of the H. pylori eradication treatment has decreased dramatically because of antibiotic resistance. To gain a more comprehensive understanding of the development status, research hotspots, and future trends related to H. pylori antibiotic resistance, we conducted a thorough retrospective analysis via the bibliometrics method. We searched the Science Citation Index Expanded of the Web of Science Core Collection for all pertinent articles on H. pylori antibiotic resistance from 2013 to 2022. R-bibliometrix, CiteSpace, and VOSviewer tools were utilized to depict statistical evaluations in order to provide an unbiased presentation and forecasts in the field. We incorporated a total of 3,509 articles related to H. pylori antibiotic resistance. Publications were inconsistent prior to 2017, but steadily increased after 2017. China generated the most papers and the United States of America received the most citations and the highest H-index. Baylor College of Medicine was the most influential institution in this field, with the highest number of publications and citations, as well as the highest H-index. Helicobacter was the most productive journal, followed by the World Journal of Gastroenterology and Frontiers in Microbiology. The World Journal of Gastroenterology had the highest citation. Graham, David Y was the most productive and cited author. Clarithromycin resistance, prevalence, gastric cancer, quadruple therapy, sequential therapy, 23S rRNA, whole genome sequencing, bismuth, and probiotics appeared with a high frequency in the keywords. The top keywords with the highest citation bursts were vonoprazan, RdxA, biofilm formation, and fatty acid chain. Our research illustrated a multi-dimensional facet and a holistic knowledge structure for H. pylori antibiotic resistance research over the past decade, which can serve as a guide for the H. pylori research community to conduct in-depth investigations in the future.

4.
Org Biomol Chem ; 21(25): 5171-5175, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37288792

RESUMO

An efficient, practical and regioselective synthesis of (E)-alkenylphosphine oxides has been developed starting from alkenes under copper catalysis and 4-HO-TEMPOH oxidation. Preliminary mechanistic studies clearly reveal that a phosphinoyl radical is involved in this process. Moreover, this method features mild reaction conditions, good functional group tolerance, and excellent regioselectivity and also promises to be efficient for the late-stage functionalization of drug molecular skeletons. The reaction will create an opportunity for the synthesis of complex phosphorus containing bioactive molecules.

5.
Nutr Cancer ; 74(10): 3735-3746, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35758096

RESUMO

This study aimed to formulate Kappaphycus alvarezii compound powder containing Kappaphycus alvarezii powder (KP), cooked sorghum powder (SP), and longan powder (LP); which was evaluated for its therapeutic effects against chemotherapy-induced intestinal mucosal injury (CIMI). Based on rheological properties, sensory evaluation, and antioxidant activity and using single factor and response surface methodology, the optimal formula to develop the compound powder was determined to be 35% KP, 30% SP, 5% LP, and 30% xylitol. Thereafter, the efficacy of the compound powder was tested by feeding BALB/c mice with diets supplemented with the Kappaphycus alvarezii compound powder (3% and 5%) for 14 consecutive days. The chemotherapeutic drug 5-fluorouracil was intraperitoneally injected (50 mg/kg) in the mice to induce CIMI for the last three consecutive days. Compared to the CIMI mice, those fed 5% Kappaphycus alvarezii compound powder (HC) showed significantly improved the intestinal injury, increased mucin-2 secretion, and reduced TNF-α, IL-1ß, IL-6, LT, and COX-2 levels. Furthermore, HC intake significantly reduced the Firmicutes-to-Bacteroidetes ratio, promoted the growth of beneficial bacteria, such as Alloprevotella, and inhibited the growth of harmful bacteria, such as Clostridium. In conclusion, HC has a protective effect against CIMI and provides a novel dietary strategy for patients undergoing chemotherapy.


Assuntos
Antineoplásicos , Mucosite , Rodófitas , Animais , Antineoplásicos/toxicidade , Fluoruracila/toxicidade , Mucosa Intestinal , Camundongos , Camundongos Endogâmicos BALB C , Mucosite/induzido quimicamente , Mucosite/tratamento farmacológico , Mucosite/prevenção & controle , Pós/efeitos adversos
6.
Nutrients ; 15(1)2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36615668

RESUMO

Selenium (Se), an essential antioxidant trace element, is reported to play a role in Parkinson's disease (PD). However, there is a lack of systematic studies on different Se forms against PD. Our study is designed to compare the neuroprotective effects of inorganic and organic Se in two classical PD mice models and investigate the underlying mechanisms for their potentially differential actions against PD. In this study, different dosages of inorganic sodium selenite (Se-Na) or organic seleno-L-methionine (Se-Met) were fed to either acute or chronic PD mice models, and their neuroprotective effects and mechanisms were explored and compared. Se-Na provided better neuroprotective effects in PD mice than Se-Met administered at the same but at a relatively low Se dosage. Se-Na treatment could influence GPX activities but not their mRNA expressions in the midbrains of PD mice. The enhanced GPX activities caused by Se-Na, but not Se-Met, in PD mice could be the major reason for the positive actions of inorganic Se to prevent dopaminergic neuronal loss in this study. In vivo bio-distribution experiments found MPTP injection greatly changed Se bio-distribution in mice, which led to reversed alterations in the bioavailability of Se-Met and Se-Na. Se-Na had higher bioavailability than Se-Met in PD mice, which could explain its better neuroprotective effects compared to Se-Met. Our results proved that Se forms and dosages determined their biological actions in mouse models of PD. Our study will provide valuable scientific evidence to researchers and/or medical professionals in using Se for PD prevention or therapy.


Assuntos
Fármacos Neuroprotetores , Doença de Parkinson , Selênio , Animais , Camundongos , Selênio/farmacologia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/prevenção & controle , Fármacos Neuroprotetores/farmacologia , Selenometionina/farmacologia , Antioxidantes/farmacologia , Selenito de Sódio , Metionina
7.
Mol Nutr Food Res ; 66(2): e2100739, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34811884

RESUMO

SCOPE: This study aims to investigate and compare the potentially neuroprotective effects and underlying mechanisms for brown seaweed polysaccharides (PS) of Alginate (Alg) and its two components, including polymannuronic acid (PM) and polyguluronic acid (PG), against Parkinson's disease (PD) pathogenesis. METHODS AND RESULTS: Model mice of PD are pretreated with Alg or PM or PG, separately via oral gavage once per day for four weeks. Our results found PM improved motor functions of PD mice, but Alg or PG did not. PM or PG, but not Alg, can prevent dopaminergic neuronal loss by increasing tyrosine hydroxylase (TH) expressions in midbrain of PD mice. The neuroprotective effects of PM rely on its anti-inflammation effects and its ability to improve striatal neurotransmitters (serotonin (5-HT) and 5-hydroxyindole acetic acid (5-HIAA)) levels in PD mice. PM inhibits inflammation, but PG or Alg induces inflammation in systemic circulation of PD mice. The neuroprotection provided by PG might be related to its ability to increase striatal neurotransmitter of 5-hydroxyindole acetic acid levels in PD mice. CONCLUSION: PM plays better than PG to provide neuroprotection, but Alg did not show any neuroprotection against PD. Alg and its two components acted differently in preventing dopaminergic neuronal loss in PD mice.


Assuntos
Fármacos Neuroprotetores , Doença de Parkinson , Alginatos/farmacologia , Animais , Modelos Animais de Doenças , Dopamina/metabolismo , Neurônios Dopaminérgicos , Camundongos , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacologia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia
8.
Nutr Cancer ; 74(6): 2113-2121, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34555987

RESUMO

5-fluorouracil (5-FU)-induced intestinal mucositis (IM) often makes chemotherapy patients suffer from physical and psychological suffering. Kappaphycus alvarezii (KA) is known for its potent multiple biological activities from decades. In the current study, we explored the effect of sun-dried and air-dried Kappaphycus alvarezii as a whole food supplement on 5-FU-induced IM. Diets supplemented with sun-dried Kappaphycus alvarezii (SKA, 3%), air-dried Kappaphycus alvarezii (AKA, 3%), and 5-aminosalicylic acid (0.005%) for consecutive14 days. While intraperitoneal injection of 5-FU (50 mg/kg) induced IM for last three consecutive days, and IM was assessed by the disease activity index (DAI) and inflammatory cytokine levels. Pretreatment of KA could alleviate phenotypic index, inhibit the increase of DAI, and reverse villus/crypt ratio. On the 14th day, AKA significantly increased the weight growth rate of the mice. The intervention of SKA significantly reduced the level of TNF-α and IL-1ß (P < 0.01, P < 0.01), while the intervention of AKA significantly inhibited the level of TNF-α, IL-1ß, and LT (P < 0.01, P < 0.01, P < 0.001). Therefore, these results showed that KA as a whole food supplement might be prevent the 5-FU-induced IM. For the first time suggest that the use of AKA might be more effective than SKA despite exact mechanism still needs further study.


Assuntos
Mucosite , Animais , Antimetabólitos Antineoplásicos/efeitos adversos , Fluoruracila/farmacologia , Humanos , Mucosa Intestinal , Intestinos , Camundongos , Mucosite/induzido quimicamente , Mucosite/tratamento farmacológico , Mucosite/prevenção & controle , Fator de Necrose Tumoral alfa/farmacologia
9.
Molecules ; 26(23)2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34885652

RESUMO

Owing to a stable and porous cage structure, natural gas hydrates can store abundant methane and serve as a potentially natural gas resource. However, the microscopic mechanism of how hydrate crystalline grows has not been fully explored, especially for the structure containing different guest molecules. Hence, we adopt density functional theory (DFT) to investigate the fusion process of structure I hydrates with CH4/C2H6 guest molecules from mono-cages to triple-cages. We find that the volume of guest molecules affects the stabilities of large (51262, L) and small (512, s) cages, which are prone to capture C2H6 and CH4, respectively. Mixed double cages (small cage and large cage) with the mixed guest molecules have the highest stability and fusion energy. The triangular triple cages exhibit superior stability because of the three shared faces, and the triangular mixed triple cages (large-small-large) structure with the mixed guest molecules shows the highest stability and fusion energy in the triple-cage fusion process. These results can provide theoretical insights into the growth mechanism of hydrates with other mono/mixed guest molecules for further development and application of these substances.

10.
Small ; 17(29): e2100949, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34145743

RESUMO

Single atom catalysts (SACs) are promising electrocatalysts for CO2 reduction reaction (CO2 RR), in which the coordination environment plays a crucial role in intrinsic catalytic activity. Taking the regular Fe porphyrin (Fe-N4 porphyrin) as a probe, the study reveals that the introduction of opposable S atoms into N coordination (Fe-N2 S2 porphyrin) allows for an appropriate electronic structural optimization on active sites. Owing to the additional orbitals around the Fermi level and the abundant Fe dz2 orbital occupation after S substitution, N, S cocoordination can effectively tune SACs and thus facilitating protonation of intermediates during CO2 RR. CO2 RR mechanisms lead to possible C1 products via two-, six-, and eight-electron pathways are systematically elucidated on Fe-N4 porphyrin and Fe-N2 S2 porphyrin. Fe-N4 porphyrin yields the most favorable product of HCOOH with a limiting potential of -0.70 V. Fe-N2 S2 porphyrin exhibits low limiting potentials of -0.38 and -0.40 V for HCOOH and CH3 OH, respectively, surpassing those of most Cu-based catalysts and SACs. Hence, the N, S cocoordination might provide better catalytic environment than regular N coordination for SACs in CO2 RR. This work demonstrates Fe-N2 S2 porphyrin as a high-performance CO2 RR catalyst, and highlights N, S cocoordination regulation as an effective approach to fine tune high atomically dispersed electrocatalysts.


Assuntos
Porfirinas , Dióxido de Carbono , Catálise , Ferro
11.
Food Funct ; 12(10): 4654-4669, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-33913445

RESUMO

Sargassum fusiforme, a nutritious edible brown alga, has been widely suggested to play an important role in the development of functional food because of its multiple biological activities. The aim of this study was to explore the anti-obesity effect of the combination of Sargassum fusiforme with extracts of fruit and vegetable by comparing the effects of Sargassum fusiforme (S), Sargassum fusiforme together with pomegranate peel extract (SP), Sargassum fusiforme together with turmeric extract (ST) and Sargassum fusiforme together with turmeric extract and pomegranate peel extract (C) on diet-induced obese C57BL/6J mice. Long-term consumption of a high-fat diet can lead to high levels of blood lipid, increase adipocyte size, and cause lipid metabolism dysfunction and gut microbiota dysbiosis. According to the results of the experiments, SP and ST were more effective in reducing lipid levels and fat accumulation than S; and, C exhibited the strongest efficacy compared with the other three supplements. ST and C also regulated adipocytokines and had significant effects on the gene expression of lipid metabolism. We also found that C alleviated the imbalance of intestinal flora caused by a high-fat diet to a certain extent. In conclusion, SP, ST and C have anti-obesity potentials, which can be used as alternative ingredients in the formula of functional food for obese people.


Assuntos
Obesidade/tratamento farmacológico , Extratos Vegetais/farmacologia , Punica granatum/química , Sargassum/química , Tecido Adiposo/metabolismo , Animais , Curcuma , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais , Inibidores Enzimáticos/farmacologia , Frutas/química , Microbioma Gastrointestinal/efeitos dos fármacos , Glucose , Metabolismo dos Lipídeos , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pâncreas/patologia
12.
Med Sci Monit ; 26: e921771, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32398636

RESUMO

BACKGROUND Qiweibaizhu powder (QWBZP) is a classical prescription of traditional Chinese medicine (TCM) to treat diarrhea in pediatric patients. Its use in health care practices and interventions has shown its effect on antibiotic-associated diarrhea (AAD). It is known that the occurrence of AAD is related to an imbalance of intestinal micro-ecology. Previous studies found that QWBZP could regulate the amount of some cultured microbes and the activities of lactase and sucrase in AAD mice. In order to investigate the treatment mechanism of QWBZP on AAD, we studied the effect of QWBZP on intestinal bacteria in a community of AAD mice. MATERIAL AND METHODS AAD mice were established by administrating the mixture of gentamycin sulfate and cefradine at the dose of 23.33 mL·kg⁻¹·d⁻¹ for 5 days. Then the AAD mice were gavaged with QWBZP decoction for 4 days and gradually recovered to a normal status. On the tenth day, the intestinal contents of mice were collected, and then the DNA was extracted for 16S rRNA sequencing followed by analysis. RESULTS The analysis of bacterial 16S rRNA sequencing showed the Simpson index was decreased and the Shannon index was increased in AAD mice treated with QWBZP compared to the model group; there was no significant difference between the control group and the treatment group (P>0.05). Principle co-ordinates analysis (PCoA) indicated that there was a shorter distance between the control group and the treatment group than that between the control group and model group. At the phylum level, use of antibiotics decreased the relative abundance of Actinobacteria, Bacteroidetes, and Proteobacteria, but increased the abundance of Firmicutes and Verrucomicrobia, and the reverse changes occurred after treated with QWBZP. At the genus level, the abundance of Bacteroides and Ochrobacitrum increased in the model group, while an opposite result was observed in the treatment group. Moreover, the relative abundance of Osillospira decreased in the model group and increased in the treatment group. Genus Dorea, Coprococcus and Blautia in the model group were higher than those in the control group and further increased in the treatment group. CONCLUSIONS These results indicated that QWBZP improved the diarrhea syndrome with restoring the diversity and adjusting the structures of bacteria in mice intestine, which might reveal the therapeutic mechanism of QWBZP on treating AAD.


Assuntos
Diarreia/tratamento farmacológico , Microbioma Gastrointestinal/efeitos dos fármacos , Medicina Tradicional Chinesa/métodos , Animais , Antibacterianos/farmacologia , Bactérias/genética , China , Feminino , Conteúdo Gastrointestinal/microbiologia , Intestinos , Masculino , Camundongos , Pós/farmacologia , RNA Ribossômico 16S/genética
13.
ACS Appl Mater Interfaces ; 9(31): 26107-26117, 2017 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-28718617

RESUMO

Surface modification by metal doping is an effective treatment technique for improving surface properties for CO2 reduction. Herein, the effects of doped Pd, Ru, and Cu on the adsorption, activation, and reduction selectivity of CO2 on CeO2(111) were investigated by periodic density functional theory. The doped metals distorted the configuration of a perfect CeO2(111) by weakening the adjacent Ce-O bond strength, and Pd doping was beneficial for generating a highly active O vacancy. The analyses of adsorption energy, charge density difference, and density of states confirmed that the doped metals were conducive for enhancing CO2 adsorption, especially for Cu/CeO2(111). The initial reductive dissociation CO2 → CO* + O* on metal-doped CeO2(111) followed the sequence of Cu- > perfect > Pd- > Ru-doped CeO2(111); the reductive hydrogenation CO2 + H → COOH* followed the sequence of Cu- > perfect > Ru- > Pd-doped CeO2(111), in which the most competitive route on Cu/CeO2(111) was exothermic by 0.52 eV with an energy barrier of 0.16 eV; the reductive hydrogenation CO2 + H → HCOO* followed the sequence of Ru- > perfect > Pd-doped CeO2(111). Energy barrier decomposition analyses were performed to identify the governing factors of bond activation and scission along the initial CO2 reduction routes. Results of this study provided deep insights into the effect of surface modification on the initial reduction mechanisms of CO2 on metal-doped CeO2(111) surfaces.

14.
Phytomedicine ; 28: 27-35, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28478810

RESUMO

BACKGROUND: An impairment of the integrity of the mucosal epithelial barrier can be observed in the course of various gastrointestinal diseases. The migration and proliferation of the intestinal epithelial (IEC-6) cells are essential repair modalities to the healing of mucosal ulcers and wounds. Atractylenolide I (AT-I), one of the major bioactive components in the rhizome of Atractylodes macrocephala Koidz. (AMR), possesses multiple pharmacological activities. This study was designed to investigate the therapeutic effects and the underlying molecular mechanisms of AT-I on gastrointestinal mucosal injury. METHODS: Scratch method with a gel-loading microtip was used to detect IEC-6 cell migration. The real-time cell analyzer (RTCA) system was adopted to evaluate IEC-6 cell proliferation. Intracellular polyamines content was determined using high performance liquid chromatography (HPLC). Flow cytometry was used to measure cytosolic free Ca2+ concentration ([Ca2+]c). mRNA and protein expression of TRPC1 and PLC-γ1 were determined by real-time PCR and Western blotting assay respectively. RESULTS: Treatment of IEC-6 cells with AT-I promoted cell migration and proliferation, increased polyamines content, raised cytosolic free Ca2+ concentration ([Ca2+]c), and enhanced TRPC1 and PLC-γ1 mRNA and protein expression. Depletion of cellular polyamines by DL-a-difluoromethylornithine (DFMO, an inhibitor of polyamine synthesis) suppressed cell migration and proliferation, decreased polyamines content, and reduced [Ca2+]c, which was paralleled by a decrease in TRPC1 and PLC-γ1 mRNA and protein expression in IEC-6 cells. AT-I reversed the effects of DFMO on polyamines content, [Ca2+]c, TRPC1 and PLC-γ1 mRNA and protein expression, and restored IEC-6 cell migration and proliferation to near normal levels. CONCLUSION: Our data demonstrate that AT-I stimulates intestinal epithelial cell migration and proliferation via the polyamine-mediated Ca2+ signaling pathway. Therefore, AT-I may have the potential to be further developed as a promising therapeutic agent to treat diseases associated with gastrointestinal mucosal injury, such as inflammatory bowel disease and peptic ulcer.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Lactonas/farmacologia , Poliaminas/metabolismo , Sesquiterpenos/farmacologia , Animais , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Eflornitina/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Fosfolipase C gama/genética , Fosfolipase C gama/metabolismo , RNA Mensageiro/metabolismo , Ratos , Canais de Cátion TRPC/genética , Canais de Cátion TRPC/metabolismo , Cicatrização/efeitos dos fármacos
15.
Artigo em Inglês | MEDLINE | ID: mdl-28373887

RESUMO

Objective. The aim of the present research is to investigate the therapeutic effect of Buyang Huanwu Decoction (BHD) in poststroke depression (PSD) animal model and illustrate its underlying mechanism via promoting neurotrophic pathway mediated neuroprotection and neurogenesis. Methods. To induce PSD rat model, isolation housed rats that received middle cerebral artery occlusion (MCAO) surgery successively suffered from chronic mild stress (CMS) treatment for consecutive twenty-one days. Meanwhile, rats were correspondingly given vehicle, BHD, and fluoxetine. Then, neurologic function was scored and depressive-like behaviors were assessed by sucrose preference test, locomotor activity, novelty-suppressed feeding test, and forced swim test. Thereafter, the neuroprotection and neurogenesis related molecular markers and signaling were detected. Results. We firstly observed a significant neurological function recovery and antidepressants effect of BHD after MCAO together with CMS treatment. Our study also found that treatment with BHD and fluoxetine can significantly rescue neurons from apoptosis and promote neurogenesis in the CA3 and DG regions in the hippocampus. Notably, BHD and fluoxetine treatment can activate BDNF/ERK/CREB signaling. Conclusion. The results suggest that BHD is a promising candidate for treating PSD. Its curative effects can be attributed to neurotrophic pathway mediated neuroprotection and neurogenesis.

16.
Toxicon ; 124: 8-14, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27810559

RESUMO

Jingzhaotoxin-XI (JZTX-XI) is a 34-residue peptide from the Chinese tarantula Chilobrachys jingzhao venom that potently inhibits both voltage-gated sodium channel Nav1.5 and voltage-gated potassium channel Kv2.1. In the present study, we further showed that JZTX-XI blocked Kv2.1 currents with the IC50 value of 0.39 ± 0.06 µM. JZTX-XI significantly shifted the current-voltage (I-V) curves and normalized conductance-voltage (G-V) curves of Kv2.1 channel to more depolarized voltages. Ala-scanning mutagenesis analyses demonstrated that mutants I273A, F274A, and E277A reduced toxin binding affinity by 10-, 16-, and 18-fold, respectively, suggesting that three common residues (I273, F274, E277) in the Kv2.1 S3b segment contribute to the formation of JZTX-XI receptor site, and the acidic residue Glu at the position 277 in Kv2.1 is the most important residue for JZTX-XI sensitivity. A single replacement of E277 with Asp(D) increased toxin inhibitory activity. These results establish that JZTX-XI inhibits Kv2.1 activation by trapping the voltage sensor in the rested state through a similar mechanism to that of HaTx1, but these two toxins have small differences in the most crucial molecular determinant. Furthermore, the in-depth investigation of the subtle differences in molecular determinants may be useful for increasing our understanding of the molecular details regarding toxin-channel interactions.


Assuntos
Peptídeos/toxicidade , Canais de Potássio Shab/efeitos dos fármacos , Venenos de Aranha/toxicidade , Sequência de Aminoácidos , Animais , Sítios de Ligação , Mutagênese Sítio-Dirigida , Homologia de Sequência de Aminoácidos , Canais de Potássio Shab/química , Canais de Potássio Shab/genética
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