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1.
Phys Chem Chem Phys ; 26(23): 16765-16773, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38819261

RESUMO

It is of great significance to search for new two-dimensional materials with excellent photocatalytic water splitting properties. Here, the AlOX (X = Cl, Br, or I) monolayers were constructed to explore their electronic and optical properties as a potential photocatalyst and mechanism of high photocatalytic activity by first principles calculations, for the first time. The results show that the AlOX (X = Cl, Br, or I) monolayers are all dynamically and thermodynamically stable. It is found that the AlOI monolayer exhibits visible optical absorption with a 538 nm absorption band edge, due to its direct band gap of 2.22 eV. Moreover, an appropriate band edge potential ensures its excellent reduction-oxidation (redox) ability. The asymmetry of crystals along different directions results in a noncoplanar HOMO and LUMO as well as an anisotropy effective mass and favors the separation of photogenerated carriers. These findings present the potential of the AlOX (X = Cl, Br, or I) monolayers as photocatalysts.

2.
Acta Pharmacol Sin ; 45(7): 1451-1465, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38491161

RESUMO

Inflammatory bowel disease (IBD) is characterized by persistent damage to the intestinal barrier and excessive inflammation, leading to increased intestinal permeability. Current treatments of IBD primarily address inflammation, neglecting epithelial repair. Our previous study has reported the therapeutic potential of notoginsenoside R1 (NGR1), a characteristic saponin from the root of Panax notoginseng, in alleviating acute colitis by reducing mucosal inflammation. In this study we investigated the reparative effects of NGR1 on mucosal barrier damage after the acute injury stage of DSS exposure. DSS-induced colitis mice were orally treated with NGR1 (25, 50, 125 mg·kg-1·d-1) for 10 days. Body weight and rectal bleeding were daily monitored throughout the experiment, then mice were euthanized, and the colon was collected for analysis. We showed that NGR1 administration dose-dependently ameliorated mucosal inflammation and enhanced epithelial repair evidenced by increased tight junction proteins, mucus production and reduced permeability in colitis mice. We then performed transcriptomic analysis on rectal tissue using RNA-sequencing, and found NGR1 administration stimulated the proliferation of intestinal crypt cells and facilitated the repair of epithelial injury; NGR1 upregulated ISC marker Lgr5, the genes for differentiation of intestinal stem cells (ISCs), as well as BrdU incorporation in crypts of colitis mice. In NCM460 human intestinal epithelial cells in vitro, treatment with NGR1 (100 µM) promoted wound healing and reduced cell apoptosis. NGR1 (100 µM) also increased Lgr5+ cells and budding rates in a 3D intestinal organoid model. We demonstrated that NGR1 promoted ISC proliferation and differentiation through activation of the Wnt signaling pathway. Co-treatment with Wnt inhibitor ICG-001 partially counteracted the effects of NGR1 on crypt Lgr5+ ISCs, organoid budding rates, and overall mice colitis improvement. These results suggest that NGR1 alleviates DSS-induced colitis in mice by promoting the regeneration of Lgr5+ stem cells and intestinal reconstruction, at least partially via activation of the Wnt/ß-Catenin signaling pathway. Schematic diagram of the mechanism of NGR1 in alleviating colitis. DSS caused widespread mucosal inflammation epithelial injury. This was manifested by the decreased expression of tight junction proteins, reduced mucus production in goblet cells, and increased intestinal permeability in colitis mice. Additionally, Lgr5+ ISCs were in obviously deficiency in colitis mice, with aberrant down-regulation of the Wnt/ß-Catenin signaling. However, NGR1 amplified the expression of the ISC marker Lgr5, elevated the expression of genes associated with ISC differentiation, enhanced the incorporation of BrdU in the crypt and promoted epithelial restoration to alleviate DSS-induced colitis in mice, at least partially, by activating the Wnt/ß-Catenin signaling pathway.


Assuntos
Colite , Ginsenosídeos , Mucosa Intestinal , Camundongos Endogâmicos C57BL , Receptores Acoplados a Proteínas G , Via de Sinalização Wnt , Animais , Ginsenosídeos/farmacologia , Ginsenosídeos/uso terapêutico , Via de Sinalização Wnt/efeitos dos fármacos , Colite/tratamento farmacológico , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Camundongos , Receptores Acoplados a Proteínas G/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Masculino , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Humanos
3.
Cancer Res ; 84(10): 1680-1698, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38501978

RESUMO

Immune checkpoint inhibitors (ICI) have transformed cancer treatment. However, only a minority of patients achieve a profound response. Many patients are innately resistant while others acquire resistance to ICIs. Furthermore, hepatotoxicity and suboptimal efficacy have hampered the clinical development of agonists of 4-1BB, a promising immune-stimulating target. To effectively target 4-1BB and treat diseases resistant to ICIs, we engineered ATG-101, a tetravalent "2+2″ PD-L1×4-1BB bispecific antibody. ATG-101 bound PD-L1 and 4-1BB concurrently, with a greater affinity for PD-L1, and potently activated 4-1BB+ T cells when cross-linked with PD-L1-positive cells. ATG-101 activated exhausted T cells upon PD-L1 binding, indicating a possible role in reversing T-cell dysfunction. ATG-101 displayed potent antitumor activity in numerous in vivo tumor models, including those resistant or refractory to ICIs. ATG-101 greatly increased the proliferation of CD8+ T cells, the infiltration of effector memory T cells, and the ratio of CD8+ T/regulatory T cells in the tumor microenvironment (TME), rendering an immunologically "cold" tumor "hot." Comprehensive characterization of the TME after ATG-101 treatment using single-cell RNA sequencing further revealed an altered immune landscape that reflected increased antitumor immunity. ATG-101 was well tolerated and did not induce hepatotoxicity in non-human primates. According to computational semimechanistic pharmacology modeling, 4-1BB/ATG-101/PD-L1 trimer formation and PD-L1 receptor occupancy were both maximized at around 2 mg/kg of ATG-101, providing guidance regarding the optimal biological dose for clinical trials. In summary, by localizing to PD-L1-rich microenvironments and activating 4-1BB+ immune cells in a PD-L1 cross-linking-dependent manner, ATG-101 safely inhibits growth of ICI resistant and refractory tumors. SIGNIFICANCE: The tetravalent PD-L1×4-1BB bispecific antibody ATG-101 activates 4-1BB+ T cells in a PD-L1 cross-linking-dependent manner, minimizing the hepatotoxicity of existing 4-1BB agonists and suppressing growth of ICI-resistant tumors. See related commentary by Ha et al., p. 1546.


Assuntos
Anticorpos Biespecíficos , Antígeno B7-H1 , Animais , Anticorpos Biespecíficos/farmacologia , Anticorpos Biespecíficos/imunologia , Humanos , Camundongos , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/antagonistas & inibidores , Feminino , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , Linhagem Celular Tumoral , Neoplasias/imunologia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Linfócitos T/imunologia , Linfócitos T/efeitos dos fármacos , Microambiente Tumoral/imunologia , Microambiente Tumoral/efeitos dos fármacos
4.
J Ethnopharmacol ; 315: 116657, 2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37244409

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Allium macrostemon Bunge (AMB), a widely distributed wild garlic plant, possesses a variety of health-promoting properties. Androgenetic alopecia (AGA) is a common disorder that affects quality of life. AIM OF THE STUDY: We sought to investigate whether AMB stimulates hair regrowth in AGA mouse model, and clarify the underlying molecular mechanisms. MATERIALS AND METHODS: The chemical constituents of AMB water extract were identified by ultra-high performance liquid chromatography-quadrupole-time of flight-mass spectrometry (UPLC-Q/TOF-MS) analysis. Cell viability assay and Ki-67 immunostaining were undertaken to evaluate the impacts of AMB on human hair dermal papilla cell (HDPC) proliferation. Wound-healing assay was undertaken to assess cell migration. Flow cytometry and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay were performed to examine cell apoptosis. Western blotting, real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR), and immunostaining assays were undertaken to determine the impacts of AMB on Wnt/ß-catenin signaling and growth factors expression in HDPC cells. AGA mouse model was induced by testosterone treatment. The effects of AMB on hair regeneration in AGA mice were demonstrated by hair growth measuring and histological scoring. The levels of ß-catenin, p-GSK-3ß, and Cyclin D1 in dorsal skin were measured. RESULTS: AMB promoted proliferation and migration, as well as the expression of growth factors in cultured HDPC cells. Meanwhile, AMB restrained apoptosis of HDPC cells by increasing the ratio of anti-apoptotic Bcl-2/pro-apoptotic Bax. Besides, AMB activated Wnt/ß-catenin signaling and thereby enhancing growth factors expression as well as proliferation of HDPC cells, which was abolished by Wnt signaling inhibitor ICG-001. In addition, an increase of hair shaft elongation was observed in mice suffering from testosterone-induced AGA upon the treatment of AMB extract (1% and 3%). Consistent with the in vitro assays, AMB upregulated the Wnt/ß-catenin signaling molecules in dorsal skin of AGA mice. CONCLUSION: This study demonstrated that AMB promoted HDPC cell proliferation and stimulated hair regrowth in AGA mice. Wnt/ß-catenin signaling activation, which induced production of growth factors in hair follicles and, eventually, contributed to the influence of AMB on the hair regrowth. Our findings may contribute to effective utilization of AMB in alopecia treatment.


Assuntos
Testosterona , beta Catenina , Camundongos , Humanos , Animais , beta Catenina/metabolismo , Testosterona/farmacologia , Plantas Comestíveis , Glicogênio Sintase Quinase 3 beta/metabolismo , Qualidade de Vida , Alopecia/induzido quimicamente , Alopecia/tratamento farmacológico , Via de Sinalização Wnt
5.
Structure ; 31(4): 424-434.e6, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36863339

RESUMO

Ca2+-dependent activator proteins for secretion (CAPSs) are required for Ca2+-regulated exocytosis in neurons and neuroendocrine cells. CAPSs contain a pleckstrin homology (PH) domain that binds PI(4,5)P2-membrane. There is also a C2 domain residing adjacent to the PH domain, but its function remains unclear. In this study, we solved the crystal structure of the CAPS-1 C2PH module. The structure showed that the C2 and PH tandem packs against one another mainly via hydrophobic residues. With this interaction, the C2PH module exhibited enhanced binding to PI(4,5)P2-membrane compared with the isolated PH domain. In addition, we identified a new PI(4,5)P2-binding site on the C2 domain. Disruption of either the tight interaction between the C2 and PH domains or the PI(4,5)P2-binding sites on both domains significantly impairs CAPS-1 function in Ca2+-regulated exocytosis at the Caenorhabditis elegans neuromuscular junction (NMJ). These results suggest that the C2 and PH domains constitute an effective unit to promote Ca2+-regulated exocytosis.


Assuntos
Proteínas de Ligação ao Cálcio , Domínios de Homologia à Plecstrina , Animais , Proteínas de Ligação ao Cálcio/química , Exocitose , Domínios Proteicos , Sítios de Ligação , Caenorhabditis elegans/metabolismo
6.
IEEE Trans Vis Comput Graph ; 29(1): 767-777, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36155462

RESUMO

Promotions are commonly used by e-commerce merchants to boost sales. The efficacy of different promotion strategies can help sellers adapt their offering to customer demand in order to survive and thrive. Current approaches to designing promotion strategies are either based on econometrics, which may not scale to large amounts of sales data, or are spontaneous and provide little explanation of sales volume. Moreover, accurately measuring the effects of promotion designs and making bootstrappable adjustments accordingly remains a challenge due to the incompleteness and complexity of the information describing promotion strategies and their market environments. We present PromotionLens, a visual analytics system for exploring, comparing, and modeling the impact of various promotion strategies. Our approach combines representative multivariant time-series forecasting models and well-designed visualizations to demonstrate and explain the impact of sales and promotional factors, and to support "what-if" analysis of promotions. Two case studies, expert feedback, and a qualitative user study demonstrate the efficacy of PromotionLens.

7.
Infect Dis Poverty ; 11(1): 91, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35986411

RESUMO

BACKGROUND: Food-borne parasitic diseases decrease food safety and threaten public health. The snail species is an intermediate host for numerous human parasitic trematodes. Orientogalba ollula has been reported as intermediate hosts of many zoonotic trematodes. Here, we investigated the prevalence of zoonotic trematodes within O. ollula in Guangxi, China, and assessed their zoonotic potential. METHODS: Snails were collected from 54 sites in 9 cities throughout Guangxi. The snail and trematode larvae species were determined by combining morphological characteristics and molecular markers. The trematodes prevalence and constituent ratio were calculated and compared among different habitat environments. Phylogenetic trees of the trematode species were constructed using the neighbor-joining method with nuclear internal transcribed spacer 2 (ITS2) sequences. The developmental cycles of the isolated trematodes were examined by experimental infection in ducks. The developmental characteristics of Echinostoma revolutum was recorded by dissecting infected ducklings from 1-day post infection (dpi) to 10 dpi. RESULTS: The overall prevalence of trematode larvae was 22.1% (1818/8238) in O. ollula from 11 sample sites. Morphological together with molecular identification, showed that E. revolutum, Australapatemon sp., Hypoderaeum conoideum, Pharyngostomum cordatum, and Echinostoma sp. parasitized O. ollula, with the highest infection rate of E. revolutum (13.0%). However, no Fasciola larvae were detected. The trematodes prevalence and constituent ratio varied in two sub-biotypes (P < 0.01). A neighbor-joining tree analysis of ITS2 sequences resulted in distinct monophyletic clades supported by sequences from isolated larvae with high bootstrap values. Ducklings exposed to O. ollula infected with Echinostoma sp., E. revolutum, and H. conoideum larvae were successfully infected. The animal model for Echinostoma revolutum was successfully established. E. revolutum matured from larvae to adult at 10 dpi in the intestine of the duck, and the developmental characteristics of E. revolutum were characterized by the maturation of the reproductive and digestive organs at 6-8 dpi. CONCLUSIONS: This study revealed a high prevalence of zoonotic trematodes in O. ollula from Guangxi, China. Existing trematodes infection in animals and human clinical cases, coupled with the wide geographical distribution of O. ollula, necessitate further evaluations of the potential risk of spillover of zoonotic infection from animal to human and vice versa.


Assuntos
Echinostoma , Animais , China/epidemiologia , Patos/parasitologia , Echinostoma/anatomia & histologia , Humanos , Modelos Animais , Filogenia , Prevalência , Caramujos/parasitologia
8.
Nutrients ; 14(11)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35684103

RESUMO

Liver disease is a global health burden with high morbidity and mortality worldwide. Liver injuries can develop into severe end-stage diseases, such as cirrhosis or hepatocellular carcinoma, without valid treatment. Therefore, identifying novel drugs may promote liver disease treatment. Phytochemicals, including polysaccharides, flavonoids, alkaloids, and terpenes, are abundant in foods and medicinal plants and have various bioactivities, such as antioxidation, immunoregulation, and tumor killing. Recent studies have shown that many natural polysaccharides play protective roles in liver disease models in vitro and in vivo, such as fatty liver disease, alcoholic liver disease, drug-induced liver injury, and liver cancer. The mechanisms of liver disease are complex. Notably, ferroptosis, a new type of cell death driven by iron and lipid peroxidation, is considered to be the key mechanism in many hepatic pathologies. Therefore, polysaccharides and other types of phytochemicals with activities in ferroptosis regulation provide novel therapeutic strategies for ferroptosis-related liver diseases. This review summarizes our current understanding of the mechanisms of ferroptosis and liver injury and compelling preclinical evidence of natural bioactive polysaccharides and phytochemicals in treating liver disease.


Assuntos
Carcinoma Hepatocelular , Ferroptose , Humanos , Peroxidação de Lipídeos , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico
9.
Front Vet Sci ; 8: 696568, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660752

RESUMO

Background: Previous epidemiological studies have confirmed non-human primates (NHPs) as reservoirs for Cryptosporidium spp. , Giardia intestinalis, and Enterocytozoon bieneusi. It highlights the possibility of interspecies transmission between humans and macaques in laboratory animal facilities. This study aimed to investigate the prevalence of pathogenic intestinal protozoan infections in macaques and humans and to determine the risk of cross-species transmission from One Health view. Materials and Methods: A total of 360 fecal samples, including 310 from the four Macaca mulatta groups, 25 from the facility workers in a laboratory animal facility, and 25 from the villagers nearby in Yongfu country, southeast China, were collected. Nested PCR assays were done for detecting protozoan pathogens from all the specimens. Furthermore, potential risk factors (gender, age, and direct contact) on the occurrence of intestinal protozoa infection among different sub-groups were evaluated. A phylogenetic and haplotype network analysis was conducted to examine the genetic structure and shared patterns of E. bieneusi and Cyclospora cayetanensis. Results: The pathogenic intestinal protozoa were detected in both human and macaque fecal samples. A total of 134 (37.2%) samples were tested positive, which included 113 (36.4%) macaques, 14 (56.0%) facility workers, and 7 (28.0%) villagers, respectively. There was no significant difference in four intestinal protozoa infections between facility workers and villagers (χ2 = 2.4, P > 0.05). However, the positive rate of pathogenic intestinal protozoa in the facility workers, who had direct contact with macaques, was significantly higher [odds ratio (OR) = 0.31, 95% confidence interval (CI): 0.09-1.00, P < 0.05).Thirty-three ITS genotypes of E. bieneusi were identified, including five known genotypes (PigEBITS7, Peru8, Henan V, D, and CM1) and six novel genotypes (MEB1-6). Seven haplotypes were identified in the network analysis from C. cayetanensis-positive samples. Meanwhile, a phylogenetic and haplotype analysis confirmed the presence of zoonotic subtypes in NHPs and humans. Conclusion: The data collected from this study confirmed a high prevalence of intestinal protozoan infection in humans and macaques. These results warrant workers of such facilities and residents to limit contact with infected animals in order to minimize related health risks. The need for comprehensive strategies to mitigate the risk of zoonotic transmission, especially from a One Health perspective, is recommended.

10.
Mol Cell Biochem ; 476(12): 4387-4403, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34460036

RESUMO

Colorectal cancer (CRC) is one of the most common human malignancies in the digestive tract with high mortality. Alantolactone (ATL), as a plant-derived sesquiterpene lactone, has shown a variety of pharmacological activities, such as antibacterial, anti-inflammatory, anti-virus and so on. However, the exact molecular mechanism of ATL in colorectal cancer remains largely unknown. Here, we performed a study to explore the effect and mechanism of ATL on colorectal cancer. The CCK-8 assay, colony formation assay, Wound-healing and Transwell assays were performed to evaluate the cytotoxic effect, antiproliferative effect, anti-migratory and anti-invasive properties of ATL respectively. The xenograft tumor model was established in Balb/c mice to evaluate the anti-tumor effect. The expression levels of proteins involved the MAPK-JNK/c-Jun signaling pathway were measured by Western blot and RT-qPCR both in cells and tumor tissues. The results showed that ATL could inhibit the cells activities of various colon cancer cell lines. Moreover, ATL could induce HCT-116 cells nuclear pyknosis, mitochondrial membrane potential loss, G0/G1 phase arrest, as well as enhance the proportion of apoptosis cells and inhibit colony formation. The migration distance and invasion rate of cells were significantly reduced after treated with ATL. Additionally, in the xenograft model, ATL (50 mg/kg) significantly decreased the tumor tumor volume and weight (p < 0.001). For the anti-colon cancer mechanism, the ATL showed the anti-proliferative and pro-apoptosis effect by activating MAPK-JNK/c-Jun signaling pathway. In conclusion, ATL exhibits anti-proliferation and apoptosis-promoting potential in colon cancer via the activation of MAPK-JNK/c-Jun signaling pathway.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Lactonas/farmacologia , Sistema de Sinalização das MAP Quinases , Sesquiterpenos de Eudesmano/farmacologia , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Anal Bioanal Chem ; 413(4): 1127-1136, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33420534

RESUMO

Antibiotic resistance has become a serious threat to food safety and public health globally. Therefore, the development of a sensitive, quick, and simple method for antibiotic susceptibility testing is an urgent and crucial need. A novel concentration gradient microfluidic chip was designed in this work to generate antibiotic concentration gradient, culture bacteria, and produce fluorescence emission. An in-house-assembled fluorescence detection platform was constructed, and experiments were conducted to verify the linearity of the generated concentration gradient, explore the appropriate incubation time and flow rate for the microfluidic chip, and study the effect of long-term acid-based food processing on antibiotic susceptibility testing. Experimental results show that the concentration gradient generated by the microfluidic chip exhibited good linearity, stability, and controllability. The appropriate flow rate and incubation time for the microfluidic chip were 2 µL/min and 5 h, respectively. The use of this microfluidic chip for testing antibiotic resistance of Salmonella to ofloxacin and ampicillin generated results that were completely consistent with test results obtained using the gold-standard method. Furthermore, Salmonella showed greater sensitivity to antibiotics under strong acid conditions, confirming the potential influence of acid-based food processing on antibiotic susceptibility testing of real samples. The designed microfluidic chip provides a high-throughput, sensitive, and rapid antibiotic susceptibility testing method that combines the microfluidic chip and the fluorescence detection platform. The application of this method would facilitate determination of antibiotic-resistant bacterial strains for clinicians and researchers, and enable monitoring of changes in bacterial resistance during food processing.


Assuntos
Antibacterianos/farmacologia , Ensaios de Triagem em Larga Escala/instrumentação , Testes de Sensibilidade Microbiana/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Salmonella/efeitos dos fármacos , Ampicilina/farmacologia , Farmacorresistência Bacteriana , Desenho de Equipamento , Humanos , Ofloxacino/farmacologia , Infecções por Salmonella/tratamento farmacológico , Infecções por Salmonella/microbiologia
12.
Biosci Rep ; 40(7)2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32687156

RESUMO

Pinocembrin, a plant-derived flavonoid, has a variety of pharmacological activities, including anti-infection, anti-cancer, anti-inflammation, cardiovascular protection, etc. However, the mechanism of pinocembrin on the anti-colitis efficacy remains elusive and needs further investigation. Here, we reported that pinocembrin eased the severity of dextran sulfate sodium (DSS)-induced colitis in mice by suppressing the abnormal activation of toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) signal pathway in vivo. In addition, the gut microbiota was disordered in DSS colitis mice, which was associated with a significant decrease in microbiota diversity and a great shift in bacteria profiles; however, pinocembrin treatment improved the imbalance of gut microbiota and made it similar to that in normal mice. On the other hand, in vitro, pinocembrin down-regulated the TLR4/NF-κB signaling cascades in lipopolysaccharide (LPS)-stimulated macrophages. At the upstream level, pinocembrin competitively inhibited the binding of LPS to myeloid differentiation protein 2 (MD2), thereby blocking the formation of receptor multimer TLR4/MD2·LPS. Furthermore, pinocembrin dose-dependently promoted the expression of tight junction proteins (ZO-1, Claudin-1, Occludin and JAM-A) in Caco-2 cells. In conclusion, our work presented evidence that pinocembrin attenuated DSS-induced colitis in mouse, at least in part, via regulating intestinal microbiota, inhibiting the over-activation of TLR4/MD2/NF-κB signaling pathway, and improving the barriers of intestine.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Disbiose/tratamento farmacológico , Flavanonas/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Células CACO-2 , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/microbiologia , Colite Ulcerativa/patologia , Colo/citologia , Colo/efeitos dos fármacos , Colo/microbiologia , Colo/patologia , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Disbiose/induzido quimicamente , Disbiose/microbiologia , Flavanonas/uso terapêutico , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Antígeno 96 de Linfócito/metabolismo , Camundongos , NF-kappa B/metabolismo , Células RAW 264.7 , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/patologia , Receptor 4 Toll-Like/metabolismo
13.
Front Pharmacol ; 11: 474, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32372959

RESUMO

Alpinetin is a naturally occurring flavonoid from the ginger plants. We previously reported the identification of alpinetin as a ligand of human pregnane X receptor (hPXR). The current study investigated the role of alpinetin as a putative PXR activator in ameliorating chemically induced inflammatory bowel disease (IBD). We found that oral administration of alpinetin significantly alleviated the severity of dextran sulfate sodium (DSS)-induced colitis in mice by decreasing the inflammatory infiltration, the levels of the pro-inflammatory mediators, and the PXR target genes in the colon. In vitro, alpinetin blocked the nuclear translocation of p-p65 in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Further, alpinetin significantly upregulated PXR target genes and inhibited TNF-α-induced NF-κB-luciferase activity in LS174T colorectal cells; however, this regulatory effects were lost when cellular PXR gene was knocked down. In PXR transactivation assays, alpinetin increased both mouse and human PXR transactivation in a dose-dependent manner. Ligand occluding mutants, S247W/C284W and S247W/C284W/S208W, in hPXR-reporter assays, abrogated alpinetin-induced hPXR transactivation. Finally, alpinetin bound to the hPXR-ligand-binding domain (LBD) was confirmed by competitive ligand binding assay. The current study significantly extends prior observations by validating a PXR/NF-κB regulatory mechanism governing alpinetin's anti-inflammatory effects in a murine model of IBD.

14.
Front Microbiol ; 11: 497, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32296403

RESUMO

Obacunone, a natural limonoid compound abundantly distributed in citrus fruits, possesses various biological properties, such as antitumor, antioxidant, and antiviral activities. Recent studies suggested an anti-inflammatory activity of obacunone in vitro, but its efficacy on intestinal inflammation remains unknown. This study was designed to evaluate the effects and mechanisms of obacunone in ameliorating intestinal inflammation in a mouse model of ulcerative colitis (UC). We found that obacunone efficiently alleviated the severity of dextran sulfate sodium (DSS)-induced mouse UC by modulating the abnormal composition of the gut microbiota and attenuating the excessive activation of toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) signaling. The intestinal epithelial barrier was disrupted in DSS colitis mice, which was associated with activation of inflammatory signaling cascades. However, obacunone promoted the expression of tight junction proteins (TJP1 and occludin) and repressed the activation of inflammatory signaling cascades. In summary, our findings demonstrated that obacunone attenuated the symptoms of experimental UC in mice through modulation of the gut microbiota, attenuation of TLR4/NF-κB signaling cascades, and restoration of intestinal epithelial barrier integrity.

15.
Front Physiol ; 11: 577237, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33536931

RESUMO

Acacetin, a natural dietary flavonoid abundantly found in acacia honey and citrus fruits, reportedly exerts several biological effects, such as anti-tumor, anti-inflammatory, and anti-oxidative effects. However, the effects of acacetin on intestinal inflammation remain unclear. We sought to investigate whether acacetin ameliorates inflammatory bowel disease (IBD) in mice with dextran sulfate sodium (DSS)-induced ulcerative colitis (UC). Our results suggest that acacetin alleviates the clinical symptoms of DSS-induced colitis, as determined by body weight loss, diarrhea, colon shortening, inflammatory infiltration, and histological injury. Further studies showed that acacetin remarkably inhibited both the macrophage inflammatory response in vitro and levels of inflammatory mediators in mice with colitis. In addition, some features of the gut microbiota were disordered in mice with DSS-induced colitis, as evidenced by a significant reduction in microbiota diversity and a marked shift in bacterial profiles. However, acacetin treatment improved this imbalance and restored gut microbiota to levels that were similar to those in normal mice. In conclusion, our work presents evidence that acacetin attenuates DSS-induced colitis in mice, at least in part, by inhibiting inflammation and regulating the intestinal microbiota.

16.
Sci Rep ; 9(1): 16636, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31719637

RESUMO

Alantolactone (ALA) is a sesquiterpene lactone with potent anti-inflammatory activity. However, the effect of ALA on intestinal inflammation remains largely unknown. The present study demonstrated that ALA significantly ameliorated the clinical symptoms of dextran sulfate sodium (DSS)-induced mice colitis as determined by body weight loss, diarrhea, colon shortening, inflammatory infiltration and histological injury. In mice exposed to DSS, ALA treatment significantly lowered pro-inflammatory mediators, including nuclear factor-kappa B (NF-κB) activation. In vitro, ALA inhibited NF-κB nuclear translocation and dose-dependently activated human/mouse pregnane X receptor (PXR), a key regulator gene in inflammatory bowel disease (IBD) pathogenesis. However, the pocket occluding mutants of the ligand-binding domain (LBD) of hPXR, abrogated ALA-mediated activation of the receptor. Overexpression of hPXR inhibited NF-κB-reporter activity and in this setting, ALA further enhanced the hPXR-mediated inhibition of NF-κB-reporter activity. Furthermore, silencing hPXR gene demonstrated the necessity for hPXR in downregulation of NF-κB activation by ALA. Finally, molecular docking studies confirmed the binding affinity between hPXR-LBD and ALA. Collectively, the current study indicates a beneficial effect of ALA on experimental IBD possibly via PXR-mediated suppression of the NF-κB inflammatory signaling.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colite/tratamento farmacológico , Lactonas/uso terapêutico , NF-kappa B/metabolismo , Receptor de Pregnano X/metabolismo , Sesquiterpenos de Eudesmano/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Animais , Colite/induzido quimicamente , Colite/metabolismo , Sulfato de Dextrana/farmacologia , Modelos Animais de Doenças , Imunofluorescência , Técnicas de Silenciamento de Genes , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Receptor de Pregnano X/efeitos dos fármacos
17.
Cogn Neurodyn ; 12(6): 561-568, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30483364

RESUMO

Differences of EEG synchronization between normal old and young people during a working memory (WM) task were investigated. The synchronization likelihood (SL) is a novel method to assessed synchronization in multivariate time series for non-stationary systems. To evaluate this method to study the mechanisms of WM, we calculated the SL values in brain electrical activity for both resting state and task state. EEG signals were recorded from 14 young adults and 12 old adults during two different states, respectively. SL was used to measure EEG synchronization between 19 electrodes in delta, theta, alpha1, alpha2 and beta frequency bands. Bad task performance and significantly decreased EEG synchronization were found in old group compared to young group in alpha1, alpha2 and beta frequency bands during the WM task. Moreover, significantly decreased EEG synchronization in beta band in the elder was also detected during the resting state. The findings suggested that reduced EEG synchronization may be one of causes for WM capacity decline along with healthy aging.

18.
Anal Chem ; 90(19): 11538-11547, 2018 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-30182713

RESUMO

Cardiovascular diseases have recently become the number one cause of death worldwide and the risk of getting cardiovascular diseases is doubled as the age increases. MicroRNA-34a (miRNA-34a) as an important potential sensor of aging and cellular senescence could be used in early diagnostics. Herein, a new ultrasensitive platform on the basis of the fluorescence resonance energy transfer (FRET) "off" to DNA circuit signal "on" principle was established, termed comet-like heterodimers gold nanoflower (AuNF) @ graphene quantum dots (GQDs) probe. We discussed that the distance of 4 nm between AuNF and GQDs would increase fluorescence quenching efficiency, and light up sensitivity after the probe combined with a target miRNA initiating DNA circuit strategy. The target miRNA-34a can be quantified down to 0.1 fM, which is about 2 orders of magnitude lower than the existing sensing protocols. Furthermore, we constructed the aging myocardial cell and animal model, and the nanoprobe presented low cytotoxicity and satisfied signal imaging in vitro and in vivo. Significantly, this platform herein is envisioned to provide a reliable guidance for early diagnosing cardiovascular diseases and proposing therapeutic protocols.


Assuntos
DNA/química , Transferência Ressonante de Energia de Fluorescência/métodos , MicroRNAs/metabolismo , Microscopia Confocal , Pontos Quânticos/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Dimerização , Ouro/química , Grafite/química , Humanos , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/sangue , Pontos Quânticos/toxicidade , Ratos
19.
Molecules ; 23(6)2018 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-29880739

RESUMO

Fargesin is a bioactive lignan from Flos Magnoliae, an herb widely used in the treatment of allergic rhinitis, sinusitis, and headache in Asia. We sought to investigate whether fargesin ameliorates experimental inflammatory bowel disease (IBD) in mice. Oral administration of fargesin significantly attenuated the symptoms of dextran sulfate sodium (DSS)-induced colitis in mice by decreasing the inflammatory infiltration and myeloperoxidase (MPO) activity, reducing tumor necrosis factor (TNF)-α secretion, and inhibiting nitric oxide (NO) production in colitis mice. The degradation of inhibitory κBα (IκBα), phosphorylation of p65, and mRNA expression of nuclear factor κB (NF-κB) target genes were inhibited by fargesin treatment in the colon of the colitis mice. In vitro, fargesin blocked the nuclear translocation of p-p65, downregulated the protein levels of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2), and dose-dependently inhibited the activity of NF-κB-luciferase in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Taken together, for the first time, the current study demonstrated the anti-inflammatory effects of fargesin on chemically induced IBD might be associated with NF-κB signaling suppression. The findings may contribute to the development of therapies for human IBD by using fargesin or its derivatives.


Assuntos
Anti-Inflamatórios/uso terapêutico , Benzodioxóis/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Lignanas/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Benzodioxóis/farmacologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Sulfato de Dextrana/administração & dosagem , Regulação da Expressão Gênica/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Doenças Inflamatórias Intestinais/induzido quimicamente , Lignanas/farmacologia , Luciferases/antagonistas & inibidores , Camundongos , NF-kappa B/genética , NF-kappa B/metabolismo , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Peroxidase/antagonistas & inibidores , Proteólise , Células RAW 264.7 , Fator de Necrose Tumoral alfa/antagonistas & inibidores
20.
Korean J Parasitol ; 54(6): 813-817, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28095669

RESUMO

Armillifer agkistrodontis (Ichthyostraca: Pantastomida) is a parasitic pathogen, only reported in China, which can cause a zoonotic disease, pentastomiasis. A complete mitochondrial (mt) genome was 16,521 bp comprising 13 protein-coding genes (PCGs), 22 tRNA genes, 2 rRNA genes, and 1 non-coding region (NCR). A phylogenetic tree drawn with the concatenated amino acid sequences of the 6 conserved PCGs (atp6, cox1-3, and nad2) showed that A. agkistrodontis and Armillifer armillatus constituted a clade Pentastomida which was a sister group of the Branchiura. The complete mt genome sequence of A. agkistrodontis provides important genetic markers for both phylogenetic and epidemiological studies of pentastomids.


Assuntos
Genoma Mitocondrial , Pentastomídeos/genética , Animais , China , Análise por Conglomerados , Genes Mitocondriais , Filogenia , Análise de Sequência de DNA , Homologia de Sequência
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