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1.
Plant Cell ; 34(5): 1804-1821, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35080617

RESUMO

Plant viruses with densely packed genomes employ noncanonical translational strategies to increase the coding capacity for viral function. However, the diverse translational strategies used make it challenging to define the full set of viral genes. Here, using tomato yellow leaf curl Thailand virus (TYLCTHV, genus Begomovirus) as a model system, we identified genes beyond the annotated gene sets by experimentally profiling in vivo translation initiation sites (TISs). We found that unanticipated AUG TISs were prevalent and determined that their usage involves alternative transcriptional and/or translational start sites and is associated with flanking mRNA sequences. Specifically, two downstream in-frame TISs were identified in the viral gene AV2. These TISs were conserved in the begomovirus lineage and led to the translation of different protein isoforms localized to cytoplasmic puncta and at the cell periphery, respectively. In addition, we found translational evidence of an unexplored gene, BV2. BV2 is conserved among TYLCTHV isolates and localizes to the endoplasmic reticulum and plasmodesmata. Mutations of AV2 isoforms and BV2 significantly attenuated disease symptoms in tomato (Solanum lycopersicum). In conclusion, our study pinpointing in vivo TISs untangles the coding complexity of a plant viral genome and, more importantly, illustrates the biological significance of the hidden open-reading frames encoding viral factors for pathogenicity.


Assuntos
Begomovirus , Solanum lycopersicum , Begomovirus/genética , Genoma Viral , Solanum lycopersicum/genética , Fases de Leitura Aberta/genética , Filogenia , Doenças das Plantas/genética
2.
Altern Ther Health Med ; 28(7): 10-17, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34559684

RESUMO

Background: For older adults, osteoarthritis (OA) is a common chronic disease that may cause pain, stiffness, and even disability of the affected knee joints. Aromatherapy might presumed to be an alternative and supplemental therapy. Primary Study Objective: To investigate the effects of aromatherapy on relieving knee pain and improving physical functions among older adults with OA. Methods/Design: A true experimental design with randomized assignment of both treatment (aromatherapy) and control (placebo) groups was used for this study. Participants: Volunteers from 3 local communities aged ≥50 y with self-reported OA-related knee pain were recruited. Interventions: A synergistic blend of essential oils diluted to a concentration of 3% was administered to participants in treatment (essential oil) group, whereas mineral oil without essential oil was applied to participants in control (placebo) group. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), including subscales of pain, stiffness, and physical function, was employed to record scores before intervention, 4 wk postintervention, and 8 wk postintervention. Pain scores were also measured and collected by using the visual analog scale at the above counterparts. The Stata v.13 software was used to perform referent statistics with a significance level (α) of 0.05 adopted. Results: The progressive linear model showed that continuous use of essential oils for 8 wk not only relieves pain immediately, but also further reduces the pain scores of participants, thus proving the long-term effect of aromatherapy on alleviating knee arthritis. Repeated measures analysis of variance further showed that time (intervention duration) is an important factor affecting all outcome scores. Except for stiffness subscales measured by WOMAC, all interactions between groups were significant. Conclusions: Aromatherapy is validated to be an effective alternative therapy in improving clinical outcomes for patients with OA-induced knee conditions. In addition, longer intervention duration (8 wk instead of 4 wk) yielded better treatment results for participants.


Assuntos
Óleos Voláteis , Osteoartrite do Joelho , Idoso , Humanos , Articulação do Joelho , Óleo Mineral/uso terapêutico , Óleos Voláteis/uso terapêutico , Osteoartrite do Joelho/tratamento farmacológico , Dor/tratamento farmacológico
3.
Clin Gastroenterol Hepatol ; 17(7): 1303-1310.e18, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-29654915

RESUMO

BACKGROUND & AIMS: The Chinese herbal medicine, MaZiRenWan (MZRW), has been used for more than 2000 years to treat constipation, but it has not been tested in a randomized controlled trial. We performed a trial to evaluate the efficacy and safety of MZRW, compared with the stimulant laxative senna or placebo, for patients with functional constipation (FC). METHODS: We performed a double-blind, double-dummy, trial of 291 patients with FC based on Rome III criteria, seen at 8 clinics in Hong Kong from June 2013 through August 2015. Patients were observed for 2 weeks and then assigned randomly (1:1:1) to groups given MZRW (7.5 g, twice daily), senna (15 mg daily), or placebo for 8 weeks. Patients were then followed for 8 weeks and evaluated at baseline and weeks 4, 8 (end of treatment), and 16 (end of follow up). Participants recorded information on stool form and frequency, feeling of complete evacuation, and research medication taken. Data on individual bowel symptoms, global symptom improvement, and adverse events were collected. A complete response was defined as an increase ≥1 complete spontaneous bowel movement (CSBM)/week from baseline (the primary outcome). Secondary outcomes included response during the follow-up period, colonic transit, individual and global symptom assessments, quality of life measured with 36-item short form Chinese version, and adverse events. RESULTS: Although there was no statistically significant difference in proportions of patients with a complete response to MZRW (68%) vs. senna (57.7%) (P = .14) at week 8, there was a statistically significant difference vs. placebo (33.0%) (P < .005). At the 16-week timepoint (after the 8-week follow-up period), 47.4% of patients had a complete response to MZRW, 20.6% had a complete response to senna, and 17.5% had a complete response to placebo (P < .005 for MZRW vs. placebo). The group that received MZRW group also had significant increases in colonic transit and reduced severity of constipation, straining, incomplete evacuation, and global constipation symptoms compared with the groups that received placebo or senna in (P < .05 for all comparisons). CONCLUSIONS: In a randomized controlled trial of 291 patients with FC, we found MZRW to be well-tolerated and effective in increasing CSBM/week. MZRW did not appear to be more effective than senna and might be considered as an alternative to this drug. ClincialTrials.gov no: NCT01695850.


Assuntos
Constipação Intestinal/tratamento farmacológico , Defecação/efeitos dos fármacos , Medicamentos de Ervas Chinesas/uso terapêutico , Qualidade de Vida , Constipação Intestinal/fisiopatologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
4.
BMC Bioinformatics ; 18(1): 165, 2017 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-28284192

RESUMO

BACKGROUND: Many computational approaches have been used for target prediction, including machine learning, reverse docking, bioactivity spectra analysis, and chemical similarity searching. Recent studies have suggested that chemical similarity searching may be driven by the most-similar ligand. However, the extent of bioactivity of most-similar ligands has been oversimplified or even neglected in these studies, and this has impaired the prediction power. RESULTS: Here we propose the MOst-Similar ligand-based Target inference approach, namely MOST, which uses fingerprint similarity and explicit bioactivity of the most-similar ligands to predict targets of the query compound. Performance of MOST was evaluated by using combinations of different fingerprint schemes, machine learning methods, and bioactivity representations. In sevenfold cross-validation with a benchmark Ki dataset from CHEMBL release 19 containing 61,937 bioactivity data of 173 human targets, MOST achieved high average prediction accuracy (0.95 for pKi ≥ 5, and 0.87 for pKi ≥ 6). Morgan fingerprint was shown to be slightly better than FP2. Logistic Regression and Random Forest methods performed better than Naïve Bayes. In a temporal validation, the Ki dataset from CHEMBL19 were used to train models and predict the bioactivity of newly deposited ligands in CHEMBL20. MOST also performed well with high accuracy (0.90 for pKi ≥ 5, and 0.76 for pKi ≥ 6), when Logistic Regression and Morgan fingerprint were employed. Furthermore, the p values associated with explicit bioactivity were found be a robust index for removing false positive predictions. Implicit bioactivity did not offer this capability. Finally, p values generated with Logistic Regression, Morgan fingerprint and explicit activity were integrated with a false discovery rate (FDR) control procedure to reduce false positives in multiple-target prediction scenario, and the success of this strategy it was demonstrated with a case of fluanisone. In the case of aloe-emodin's laxative effect, MOST predicted that acetylcholinesterase was the mechanism-of-action target; in vivo studies validated this prediction. CONCLUSIONS: Using the MOST approach can result in highly accurate and robust target prediction. Integrated with a FDR control procedure, MOST provides a reliable framework for multiple-target inference. It has prospective applications in drug repurposing and mechanism-of-action target prediction.


Assuntos
Ligantes , Aprendizado de Máquina , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Aloe/química , Aloe/metabolismo , Animais , Catárticos/química , Catárticos/metabolismo , Bases de Dados de Compostos Químicos , Emodina/química , Emodina/metabolismo , Humanos , Cinética , Modelos Logísticos
5.
Molecules ; 22(7)2017 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-28726741

RESUMO

Magnolol is a lignan with anti-inflammatory activity identified in Magnolia officinalis. Ulcerative colitis (UC), one of the types of inflammatory bowel disease (IBD), is a disease that causes inflammation and ulcers in the colon. To investigate the effect of magnolol in dextran sulfate sodium (DSS)-induced experimental UC model, male C57 mice were treated with 2% DSS drinking water for 5 consecutive days followed by intragastric administration with magnolol (5, 10 and 15 mg/kg) daily for 7 days. The results showed that magnolol significantly attenuated disease activity index, inhibited colonic shortening, reduced colonic lesions and suppressed myeloperoxidase (MPO) activity. Moreover, colonic pro-inflammatory cytokines (TNF-α, IL-6, and IL-1ß) induced by colitis were dramatically decreased by magnolol. To further unveil the metabolic signatures upon magnolol treatment, mass spectrometry-based metabolomic analysis of the small molecular metabolites in mice serum were performed. Compared with controls, abnormality of serum metabolic phenotypes in DSS-treated mice were effectively reversed by different doses of magnolol. In particular, magnolol treatment effectively elevated the serum levels of tryptophan metabolites including kynurenic acid (KA), 5-hydroxyindoleacetic acid, indoleacetic acid (IAA), indolelactic acid and indoxylsulfuric acid, which are potential aryl hydrocarbon receptor (AHR) ligands to impact colitis. These findings suggest that magnolol exerts anti-inflammatory effect on DSS-induced colitis and its underlying mechanisms are associated with the restoring of tryptophan metabolites that inhibit the colonic inflammation.


Assuntos
Compostos de Bifenilo/uso terapêutico , Colite/induzido quimicamente , Colite/tratamento farmacológico , Sulfato de Dextrana/toxicidade , Lignanas/uso terapêutico , Polifenóis/uso terapêutico , Animais , Colite/sangue , Ácidos Indolacéticos/sangue , Indóis/sangue , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Ácido Cinurênico/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator de Necrose Tumoral alfa/metabolismo
6.
Pharmacol Res ; 110: 227-239, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26969793

RESUMO

Ulcerative colitis (UC) is an increasingly common condition particularly in developed countries. The lack of satisfactory treatment has fueled the search for alternative therapeutic strategies. In recent studies, berberine, a plant alkaloid with a long history of medicinal use in Chinese medicine, has shown beneficial effects against animal models of acute UC. However, UC usually presents as a chronic condition with frequent relapse in patients. How berberine will act on chronic UC remains unclear. In the present study, we adopted dextran sulfate sodium (DSS)-induced chronic relapsing colitis model to assess the ameliorating activity of berberine. Colitis was induced by two cycles of 2.0% DSS for five days followed by 14days of drinking water plus a third cycle consisting of DSS only for five days. The colitis mice were orally administered 20mg/kg berberine from day 13 onward for 30days and monitored daily. The body weight, stool consistency, and stool bleeding were recorded for determination of the disease activity index (DAI). At the end of treatment, animals were sacrificed and samples were collected and subjected to histological, RT-qPCR, Western blot, and LC-MS analyses. Lymphocytes were isolated from spleens and mesenteric lymph nodes (MLN) and cultured for flow cytometry analysis of IL-17 secretion from CD4(+) cells and the Th17 cell differentiation. Results showed that berberine significantly ameliorated the DAI, colon shortening, colon tissue injury, and reduction of colonic expression of tight junction (TJ) protein ZO-1 and occludin of colitis mice. Notably, berberine treatment pronouncedly reduced DSS-upregulated Th17-related cytokine (IL-17 and ROR-γt) mRNAs in the colon. Furthermore, the mRNA expression of IL-6 and IL-23, and the phosphorylation of STAT3 in colon tissues from DSS-treated mice were pronouncedly inhibited by berberine. Moreover, the up-regulation of IL-17 secretion from CD4(+) cells of spleens and MLNs caused by DSS were significantly reversed by berberine treatment. Furthermore, Th17 cell differentiation from naive CD4(+) cells isolated from above DSS colitis mice were suppressed by berberine in a concentration-dependent manner. In summary, we demonstrated for the first time that berberine reduced the severity of chronic relapsing DSS-induced colitis by suppressing Th17 responses. The demonstration of activity in this mouse model supports the possibility of clinical efficacy of berberine in treating chronic UC.


Assuntos
Berberina/farmacologia , Colite/tratamento farmacológico , Colo/efeitos dos fármacos , Sulfato de Dextrana , Fármacos Gastrointestinais/farmacologia , Interleucina-17/metabolismo , Células Th17/efeitos dos fármacos , Animais , Células Cultivadas , Doença Crônica , Colite/induzido quimicamente , Colite/imunologia , Colite/metabolismo , Colo/imunologia , Colo/metabolismo , Colo/patologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Imunossupressores/farmacologia , Interleucina-17/genética , Interleucina-17/imunologia , Interleucina-23/genética , Interleucina-23/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Fenótipo , Fosforilação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Recidiva , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Th17/imunologia , Células Th17/metabolismo , Fatores de Tempo
7.
J Nat Prod ; 79(4): 1056-62, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-26905227

RESUMO

The immunoregulatory protective properties of (+)-3'α-angeloxy-4'-keto-3',4'-dihydroseselin (Pd-Ib) isolated from Bupleurum malconense has not been reported. In the present study, the therapeutic effect of Pd-Ib (30, 60, and 120 mg/kg/day) was examined in a mouse model of dextran sulfate sodium (DSS)-induced acute colitis. Administration of Pd-Ib significantly reduced the disease activity index, inhibited the shortening of colon length, reduced colonic tissue damage, and suppressed colonic myeloperoxidase activity and nitric oxide levels in mice with DSS-induced colitis. Moreover, Pd-Ib greatly suppressed the secretion of pro-inflammatory cytokines TNF-α, IFN-γ, IL-6, and IL-17A while enhancing the level of anti-inflammatory cytokine IL-4. The protein levels of phosphorylated STAT3 (p-STAT3) and phosphorylated p38 (p-p38) were down-regulated in the colonic tissues of DSS-treated mice. Importantly, the anti-inflammatory effect of Pd-Ib against acute colitis was comparable to the anti-inflammatory sulfa drug sulfasalazine (300 mg/kg). Furthermore, the in vitro study showed that the inhibitory effect of Pd-Ib on p-STAT3 and IL-6 protein levels was accompanied by the reduction of MAPKs (JNK and p38). In conclusion, this study suggested that Pd-Ib attenuated DSS-induced acute colitis via the regulation of interleukins principally through the STAT3 and MAPK pathways.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Bupleurum/química , Colite/induzido quimicamente , Cumarínicos/isolamento & purificação , Cumarínicos/farmacologia , Sulfato de Dextrana/efeitos adversos , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/química , Colo/efeitos dos fármacos , Cumarínicos/administração & dosagem , Cumarínicos/química , Citocinas/metabolismo , Modelos Animais de Doenças , Interleucina-17/uso terapêutico , Interleucina-4/metabolismo , Interleucina-6/metabolismo , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Quinases de Proteína Quinase Ativadas por Mitógeno/efeitos dos fármacos , Estrutura Molecular , NF-kappa B/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Fator de Transcrição STAT3/efeitos dos fármacos , Estereoisomerismo , Sulfassalazina/farmacologia
8.
Pharm Biol ; 52(3): 356-61, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24143857

RESUMO

CONTEXT: Polygonum cuspidatum Sieb et Zucc. (Polygonaceae) possesses various pharmacological activities and has been widely using as one of the most popular and valuable Chinese herbal medicines in clinics. Its usage has increasingly attracted much of our attention and urges investigation on its bioactive components. OBJECTIVE: To establish a rapid and valid approach for screening potential neuroprotective components from P. cuspidatum. MATERIALS AND METHODS: Potential neuroprotective components from P. cuspidatum were screened utilizing liposome equilibrium dialysis followed by high-performance liquid chromatography (HPLC) analysis. Their neuroprotective effects on modulation of protein expression of α7 nAChR, α3 nAChR and synaptophysin (SPY) on SH-SY5Y human neuroblastoma cell line (SH-SY5Y) were evaluated by means of Western blotting. RESULTS: Two potential compounds, polydatin (C1) and emodin-8-O-ß-D-glucoside (C2), were detected and identified in our study. The biological tests showed that both compounds C1 and C2, respectively, at concentrations of 0.1 and 0.25 mg/mL significantly increased protein expression of α7 and α3 nicotinic acetylcholine receptors (nAChRs) in SH-SY5Y cells. Moreover, C1 and C2 at 0.1 mg/mL significantly reversed the Aß1₋42-induced decrease of α7 and α3 nAChRs protein expression in SH-SY5Y cells. In addition, C2 at 0.1 mg/mL significantly increased protein expression of SPY in SH-SY5Y cells and Aß11₋42-induced SH-SY5Y cells whereas C1 did not provide any positive effects. DISCUSSION AND CONCLUSION: In conclusion, our approach utilizing liposome equilibrium dialysis combined with HPLC analysis and cell-based assays is a prompt and useful method for screening neuroprotective agents.


Assuntos
Fallopia japonica/química , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Antraquinonas/administração & dosagem , Antraquinonas/isolamento & purificação , Antraquinonas/farmacologia , Western Blotting , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão/métodos , Diálise/métodos , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glucosídeos/administração & dosagem , Glucosídeos/isolamento & purificação , Glucosídeos/farmacologia , Humanos , Lipossomos , Neuroblastoma/patologia , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/isolamento & purificação , Permeabilidade , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Receptores Nicotínicos/genética , Estilbenos/administração & dosagem , Estilbenos/isolamento & purificação , Estilbenos/farmacologia , Receptor Nicotínico de Acetilcolina alfa7/genética
9.
J Nat Prod ; 76(11): 2120-5, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24200352

RESUMO

The therapeutic effect of corilagin (1) was evaluated in an acute colitis model induced by dextran sulfate sodium (DSS) in mice, and the mechanism of action was investigated in this study. Animals were challenged with 2% DSS drinking water for 5 consecutive days and then intraperitoneally treated with 1 (7.5, 15, and 30 mg/kg) daily for 7 days. It was found that 1 significantly decreased the disease activity index, inhibited the shortening of colon length, reduced colon tissue damage, and suppressed myeloperoxidase activity. Moreover, 1 greatly suppressed the secretion of TNF-α, IL-6, and IL-1ß, inhibited the degradation of IκB α, and down-regulated expression of cleaved caspase-3 and cleaved caspase-9 in colon tissues of DSS-treated mice. These findings demonstrated that 1 exerts a protective effect on DSS-induced colitis, and its underlying mechanisms are associated with inhibition of the NF-κB pathway that mitigates colon inflammatory responses and apoptosis of intestinal epithelial cells.


Assuntos
Colite Ulcerativa/induzido quimicamente , Sulfato de Dextrana/efeitos adversos , Glucosídeos/farmacologia , Taninos Hidrolisáveis/farmacologia , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 9/metabolismo , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colo/enzimologia , Colo/metabolismo , Água Potável/química , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Glucosídeos/química , Interleucina-16/antagonistas & inibidores , Interleucina-16/metabolismo , Interleucina-1beta/metabolismo , Interleucina-1beta/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Peroxidase/antagonistas & inibidores , Peroxidase/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
10.
Front Immunol ; 14: 1292019, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38288120

RESUMO

Background: Nectin-4 is a novel biomarker overexpressed in various types of cancer, including breast cancer, in which it has been associated with poor prognosis. Current literature suggests that nectin-4 has a role in cancer progression and may have prognostic and therapeutic implications. The present study aims to produce nectin-4-specific single-chain variable fragment (scFv) antibodies and evaluate their applications in breast cancer cell lines and clinical specimens. Methods: We generated recombinant nectin-4 ectodomain fragments as immunogens to immunize chickens and the chickens' immunoglobulin genes were amplified for construction of anti-nectin-4 scFv libraries using phage display. The binding capacities of the selected clones were evaluated with the recombinant nectin-4 fragments, breast cancer cell lines, and paraffin-embedded tissue sections using various laboratory approaches. The binding affinity and in silico docking profile were also characterized. Results: We have selected two clones (S21 and L4) from the libraries with superior binding capacity. S21 yielded higher signals when used as the primry antibody for western blot analysis and flow cytometry, whereas clone L4 generated cleaner and stronger signals in immunofluorescence and immunohistochemistry staining. In addition, both scFvs could diminish attachment-free cell aggregation of nectin-4-positive breast cancer cells. As results from ELISA indicated that L4 bound more efficiently to fixed nectin-4 ectodomain, molecular docking analysis was further performed and demonstrated that L4 possesses multiple polar contacts with nectin-4 and diversity in interacting residues. Conclusion: Overall, the nectin-4-specific scFvs could recognize nectin-4 expressed by breast cancer cells and have the merit of being further explored for potential diagnostic and therapeutic applications.


Assuntos
Neoplasias , Anticorpos de Cadeia Única , Animais , Anticorpos de Cadeia Única/genética , Nectinas , Biomarcadores Tumorais , Simulação de Acoplamento Molecular , Galinhas
11.
Front Pharmacol ; 13: 1085309, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36712668

RESUMO

Liver cancer belongs to Gastrointestinal (GI) malignancies which is a common clinical disease, a thorny public health problem, and one of the major diseases that endanger human health. Molecules from natural products (NPs) or their derivatives play an increasingly important role in various chronic diseases such as GI cancers. The chemical composition of the Alstonia yunnanensis Diels roots was studied using silica column chromatography, gel chromatography, recrystallization, and HPLC, and the compounds were structurally identified by modern spectral analysis using mass spectrometry (MS) and nuclear magnetic resonance (1H-, 13C-, HMQC-, HMBC-, and 1H-1HCOSY-NMR), ultraviolet and visible spectrum (UV), and electronic Circular Dichroism (ECD). Acetoxytabernosine (AC), an indole alkaloid with antitumor activity, was isolated from Alstonia yunnanensis Diels root. The current study aimed to investigate the influence of AC on the cell proliferation of BEL-7402 and SMMC7721 and to elucidate the underlying mechanism. The absolute configuration of AC was calculated by ECD (electronic circular dichroism). The effects of AC on the viability of different tumor cell lines were studied by the SRB method. The death mode of human hepatoma cells caused by AC was studied by TUNEL cell apoptosis detection and AnnexinV-FITC/PI double staining image. Mitochondrial membrane potential was detected by JC-1. The effects of AC on the expression of apoptosis-related proteins (Caspase9, Caspase3, and Parp-1) in SMMC7721 and BEL-7402 cells were detected by western blot. It was found that the absolute configuration of AC is 19(s), 20(s)-Acetoxytabernosine. AC could induce apoptosis of SMMC7721 and BEL-7402, and block the replication of DNA in the G1 phase. Under the treatment of AC, the total protein expression of apoptosis-related proteins (Caspase9, Caspase3, and Parp-1) significantly decreased in SMMC7721 and BEL-7402. The results suggested that AC induced apoptosis through a caspase-dependent intrinsic pathway in SMMC7721 and BEL-7402, and natural product-based drug development is an important direction in antitumor drug discovery and research.

12.
Nat Commun ; 13(1): 3749, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35768470

RESUMO

Insulin sensitivity progressively declines with age. Currently, the mechanism underlying age-associated insulin resistance remains unknown. Here, we identify membrane-bound matrix metalloproteinase 14 (MT1-MMP/MMP14) as a central regulator of insulin sensitivity during ageing. Ageing promotes MMP14 activation in insulin-sensitive tissues, which cleaves Insulin Receptor to suppress insulin signaling. MT1-MMP inhibition restores Insulin Receptor expression, improving insulin sensitivity in aged mice. The cleavage of Insulin Receptor by MT1-MMP also contributes to obesity-induced insulin resistance and inhibition of MT1-MMP activities normalizes metabolic dysfunctions in diabetic mouse models. Conversely, overexpression of MT1-MMP in the liver reduces the level of Insulin Receptor, impairing hepatic insulin sensitivity in young mice. The soluble Insulin Receptor and circulating MT1-MMP are positively correlated in plasma from aged human subjects and non-human primates. Our findings provide mechanistic insights into regulation of insulin sensitivity during physiological ageing and highlight MT1-MMP as a promising target for therapeutic avenue against diabetes.


Assuntos
Resistência à Insulina , Metaloproteinase 14 da Matriz , Receptor de Insulina , Fatores Etários , Animais , Humanos , Insulina/metabolismo , Metaloproteinase 14 da Matriz/metabolismo , Camundongos , Receptor de Insulina/metabolismo , Transdução de Sinais
13.
Nat Metab ; 4(2): 203-212, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35177851

RESUMO

GDNF-family receptor a-like (GFRAL) has been identified as the cognate receptor of growth/differentiation factor 15 (GDF15/MIC-1), considered a key signaling axis in energy homeostasis and body weight regulation. Currently, little is known about the physiological regulation of the GDF15-GFRAL signaling pathway. Here we show that membrane-bound matrix metalloproteinase 14 (MT1-MMP/MMP14) is an endogenous negative regulator of GFRAL in the context of obesity. Overnutrition-induced obesity increased MT1-MMP activation, which proteolytically inactivated GFRAL to suppress GDF15-GFRAL signaling, thus modulating the anorectic effects of the GDF15-GFRAL axis in vivo. Genetic ablation of MT1-MMP specifically in GFRAL+ neurons restored GFRAL expression, resulting in reduced weight gain, along with decreased food intake in obese mice. Conversely, depletion of GFRAL abolished the anti-obesity effects of MT1-MMP inhibition. MT1-MMP inhibition also potentiated GDF15 activity specifically in obese phenotypes. Our findings identify a negative regulator of GFRAL for the control of non-homeostatic body weight regulation, provide mechanistic insights into the regulation of GDF15 sensitivity, highlight negative regulators of the GDF15-GFRAL pathway as a therapeutic avenue against obesity and identify MT1-MMP as a promising target.


Assuntos
Metaloproteinase 14 da Matriz , Obesidade , Animais , Anorexia/metabolismo , Peso Corporal , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Metaloproteinase 14 da Matriz/uso terapêutico , Camundongos , Obesidade/metabolismo
14.
J Med Chem ; 64(23): 17051-17062, 2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34699215

RESUMO

Triple-negative breast cancer (TNBC) is a heterogeneous subtype of breast cancer with poor prognosis. Here, we present a peptide-drug conjugate (PDC)─bradykinin-potentiating peptide-paclitaxel (BPP-PTX) conjugate─synthesized by conjugating BPP9a with PTX via a succinyl linker. BPP-PTX targets the angiotensin-converting enzyme (ACE) on TNBC cells. ACE was found to be ectopically expressed in two TNBC cell lines but was absent in both the receptor-positive breast cancer cell line and healthy kidney cell line. Overexpression, knockdown, and competitive inhibition experiments demonstrated ACE-mediated cytotoxicity of BPP-PTX. In vivo, ACE-positive tumors were enriched with BPP-PTX, with the PDC being better tolerated than plain PTX. Compared with plain PTX, BPP-PTX exhibited improved tumor-suppressive effects in MDA-MB-468 xenografted female nude mice. Meanwhile, BPP-PTX resulted in less body weight loss and white blood cell reduction toxicity. These results collectively imply the novelty, efficacy, and low-toxicity profile of BPP-PTX as a potential therapeutic for ACE-positive TNBC.


Assuntos
Bradicinina/química , Oligopeptídeos/farmacologia , Paclitaxel/farmacologia , Peptidil Dipeptidase A/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Camundongos Nus , Oligopeptídeos/química , Oligopeptídeos/farmacocinética , Paclitaxel/química , Distribuição Tecidual , Neoplasias de Mama Triplo Negativas/enzimologia
15.
Chin J Integr Med ; 27(8): 604-612, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32248515

RESUMO

OBJECTIVE: To investigate the mechanism of Tojapride, a Chinese herbal formula extract, on strengthening the barrier function of esophageal epithelium in rats with reflux esophagitis (RE). METHODS: Ten out of 85 SD rats were randomly selected as the sham group (n10), and 75 rats were developed a reflux esophagitis model (RE) by the esophageal and duodenal side-to-side anastomosis. Fifty successful modeling rats were divided into different medicated groups through a random number table including the model, low-, medium-, and high-dose of Tojapride as well as omeprazole groups (n10). Three doses of Tojapride [5.73, 11.46, 22.92 g/(kg•d)] and omeprazole [4.17 mg/(kg•d)] were administrated intragastrically twice daily for 3 weeks. And the rats in the sham and model groups were administered 10 mL/kg distilled water. Gastric fluid was collected and the supernatant was kept to measure for volume, pH value and acidity. Esophageal tissues were isolated to monitor the morphological changes through hematoxylin-eosin (HE) staining, and esophageal epithelial ultrastructure was observed by transmission electron microscopy. The expressions of nuclear factor kappa-light-chain-enhancer of activated B cells p65 (NF-KBp65), κB kinase beta (IKKß), occludin, and zonula occludens-1 (ZO-1) in the esophageal tissues were measured by immunohistochemistry and Western blot, respectively. RESULTS: The gastric pH value in the model group was significantly lower than the sham group (P<0.05). Compared with the model group, gastric pH value in the omeprazole and medium-dose of Tojapride groups were significantly higher (P<0.05). A large area of ulceration was found on the esophageal mucosa from the model rats, while varying degrees of congestion and partially visible erosion was observed in the remaining groups. Remarkable increase in cell gap width and decrease in desmosome count was seen in RE rats and the effect was reversed by Tojapride treatment. Compared with the sham group, the IKKß levels were significantly higher in the model group (P<0.05). However, the IKKß levels were down-regulated after treatment by all doses of Tojapride (P<0.01 or P<0.05). The occluding and ZO-1 levels decreased in the model group compared with the sham group (Ps0.01 or Ps0.05), while both indices were significantly up-regulated in the Tojapride-treated groups (P<0.01 or P<0.05). CONCLUSIONS: Tojapride could improve the pathological conditions of esophageal epithelium in RE rats. The underlying mechanisms may involve in down-regulating the IKKß expression and elevating ZO-1 and occludin expression, thereby alleviating the inflammation of the esophagus and strengthening the barrier function of the esophageal epithelium.


Assuntos
Esofagite Péptica , Animais , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Esofagite Péptica/tratamento farmacológico , Ocludina , Ratos , Ratos Sprague-Dawley
16.
Medicine (Baltimore) ; 99(15): e19781, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32282741

RESUMO

INTRODUCTION: Surgical stress and pain are potential provoking factors for postoperative myasthenic crisis (POMC). We report the occurrence of early POMC and late deep vein thrombosis (DVT) in a man with myasthenia gravis (MG) undergoing thymectomy, addressing possible link between reversal of opioid overdose with naloxone and the triggering of POMC. PATIENT CONCERNS: A 71-year-old man with impaired renal function (ie, estimated glomerular filtration rate [egfr]: 49.1 mL/min/1.73 m) with diagnosis of MG made 2 months ago was scheduled for thymectomy. After uncomplicated surgery, he experienced opioid overdose that was treated with naloxone. Hyperlactatemia then developed with a concomitant episode of hypertension. Three hours after reversal, he suffered from myasthenic crisis presenting with respiratory failure and difficult weaning from mechanical ventilation. DIAGNOSIS: Stress-induced hyperlactatemia and subsequent myasthenic crisis INTERVENTIONS:: Pyridostigmine and immunosuppressive therapy with prednisolone were initiated. Hyperlactatemia subsided on postoperative day (POD) 5. Tracheal extubation was performed successfully on POD 6. OUTCOMES: During the course of hospitalization, his eGFR (ie, 88.9 mL/min/1.73 m) was found to improve postoperatively. After discharge from hospital, he developed DVT in the left femoral and popliteal veins on POD 24 when he was readmitted for immediate treatment with low-molecular-weight heparin. He was discharged without sequelae on POD 31. There was no recurrence of myasthenic crisis or DVT at 3-month follow-up. CONCLUSIONS: Following naloxone administration, hyperlactatemia may be an indicator of pain-related stress response, which is a potential provoking factor for myasthenic crisis. Additionally, patients with MG may have an increased risk of DVT possibly attributable to immune-mediated inflammation. These findings highlight the importance of perioperative avoidance of provoking factors including monitoring of stress-induced elevations in serum lactate concentration, close postoperative surveying for myasthenic crisis, and early recognition of possible thromboembolic complications in this patient population.


Assuntos
Miastenia Gravis/complicações , Timectomia/efeitos adversos , Trombose Venosa/etiologia , Idoso , Anticoagulantes/administração & dosagem , Anticoagulantes/uso terapêutico , Inibidores da Colinesterase/administração & dosagem , Inibidores da Colinesterase/uso terapêutico , Heparina de Baixo Peso Molecular/administração & dosagem , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Hiperlactatemia/induzido quimicamente , Hiperlactatemia/diagnóstico , Hiperlactatemia/tratamento farmacológico , Hipertensão/induzido quimicamente , Hipertensão/diagnóstico , Imunossupressores/administração & dosagem , Imunossupressores/uso terapêutico , Masculino , Miastenia Gravis/diagnóstico , Miastenia Gravis/cirurgia , Naloxona/efeitos adversos , Antagonistas de Entorpecentes/efeitos adversos , Transtornos Relacionados ao Uso de Opioides/complicações , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Readmissão do Paciente , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/patologia , Prednisolona/administração & dosagem , Prednisolona/uso terapêutico , Brometo de Piridostigmina/administração & dosagem , Brometo de Piridostigmina/uso terapêutico , Respiração Artificial/métodos , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapia , Resultado do Tratamento
17.
Sci Rep ; 10(1): 19446, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33149142

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

18.
Front Pharmacol ; 11: 576496, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33658925

RESUMO

Ulcerative colitis (UC) causes chronic inflammation and damage to the colonic mucosal layer. Recent studies have reported significant changes in phosphatidylcholine (PC) and lysophosphatidylcholine (LPC) in UC patients and oral administration of PC has considerable therapeutic effects against UC, suggesting the metabolism of phosphatidylcholine may be involved in the UC development. Our previous work has demonstrated that berberine effectively suppresses inflammation and protects colonic mucosa injury in DSS-induced colitic mice. However, whether the therapeutic effects of berberine are attributed to its action on the PC metabolism remains unknown. In the present study, we have shown that berberine significantly reduces the lysophosphatidylcholine (LPC) levels in the sera of DSS-induced experimental colitis mice and LPS-stimulated macrophage RAW 264.7 cells. The cytosolic phospholipase A2a (PLA2G4A), an enzyme for hydrolyzing PC to LPC, was found to be up-regulated in the colon tissue of experimental colitis mice and inflamed macrophage RAW 264.7 cells. We then demonstrated berberine inhibits the phosphorylation of cytosolic phospholipase A2a (PLA2G4A) in the colon tissue of experimental colitis mice and inflamed macrophage RAW 264.7 cells. Subsequently, we revealed berberine suppressed the expression of pro-inflammatory factors including TNF-alpha and IL-6 through regulating PLA2G4A dysfunction in macrophage RAW 264.7 cells. Mechanistically, we found that berberine directly binds to PLA2G4A and inhibits MAPK/JNK signaling pathway to inhibit PLA2G4A activity in inflammatory status. Therefore, we concluded that berberine inhibits colonic PLA2G4A activity to ameliorate colonic inflammation in experimental colitic mice, suggesting modulation of the PC metabolism via PLA2G4A might be beneficial for establishing new therapies strategy for UC.

19.
Chin Med ; 14: 28, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31406501

RESUMO

BACKGROUND: Cyclocarya paliurus (Batal.) Ijinskaja (CP) is a monotypic genus plant, also called sweet tea tree that belongs to the Juglandaceae family, which is mainly distributed in the subtropical highlands in China. Our previous work has verified that CP leaves exhibit a potent hyperglycemic effect by inhibiting pancreatic ß cell apoptosis through the regulation of MPAK and Akt signaling pathways. However, the components that contribute to this potential health benefit remain undiscovered. METHOD: A sensitive, reliable, and validated ultra-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (UPLC-TQ-MS/MS) method was developed to simultaneously determine the presence of six active components (neochlorogenic acid, chlorogenic acid, quercetin-3-O-glucuronide, kaempferol-3-O-rhamnoside, quercetin, and kaempferol) in rat plasma after a single oral administration (in a dosage of 10.5 g/kg) of an extract of CP leaves to rats. The separation was performed on a Waters ACQUITY BEH C18 column (50 mm × 2.1 mm, 1.7 µm). The detection was conducted by multiple reaction monitoring (MRM) in negative ionization mode. The two highest abundant MRM transitions without interference were optimized for each analyte. Acetonitrile and formic acid aqueous solution (0.1%) was used as the mobile phase at a flow rate of 0.3 ml/min. RESULT: The precision, accuracy, and recovery all satisfied the criteria of international guidance (Bioanalytical Method Validation Guidance for Industry, Food and Drug Administration), and the analytes were stable in plasma for all tested conditions. The main pharmacokinetic parameters were calculated by plasma concentration versus time profiles using the pharmacokinetics program. CONCLUSION: The pharmacokinetic parameters of each compound can facilitate future clinical studies.

20.
Front Pharmacol ; 10: 1570, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32038247

RESUMO

In a prospective, randomized, three-arms, controlled clinical study, Chinese Herbal Medicine MaZiRenWan (MZRW, also known as Hemp Seed Pill) demonstrates comparable efficacy with Senna for functional constipation (FC) during an 8-week treatment period. Both MZRW and Senna are better than a placebo; relative to Senna and a placebo, MZRW displayed a more sustained effect during the 8-week follow-up period. The characteristic pharmacological mechanism responsible for this observation is still unclear. To explore this, we collected pre- and post-treatment serum samples of 85 FC patients from MZRW/Senna/placebo treatment groups for pharmacometabolomic analysis. An ultrahigh-performance liquid chromatography-mass spectrometer (UPLC-MS) was used for metabolic profiling and quantification. In vivo studies were conducted in constipated C57BL/6J mice to verify the effects and corresponding mechanism(s) of the action of MZRW. Pearson correlation analysis, paired t-test, one-way ANOVA analysis, χ2 test, and Student t-test were used to interpret the clinical and preclinical data. Changes in levels of circulating oleamide and its derivatives negatively correlate with improvement in complete spontaneous bowel movement (CSBM) in the MZRW group (Pearson r = -0.59, p = 0.00057). The same did not hold true for either Senna or placebo groups. Oleamide is a known regulator of intestinal motility. MZRW treatment resulted in reduced levels of circulating oleamide in FC patients. Experimental verification showed that MZRW attenuated oleamide-induced slow intestinal motility in mice. MZRW decreased oleamide levels in serum, ileum, and colon in normal mice, but increased expression of colonic fatty acid amide hydrolase (FAAH). In conclusion, MZRW improved bowel movement in FC by down-regulating oleamide, possibly by enhancing FAAH-mediated degradation. Our findings suggest a novel therapeutic strategy for FC.

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