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1.
J Virol ; 97(6): e0068923, 2023 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-37289083

RESUMO

Goblet cells and their secreted mucus are important elements of the intestinal mucosal barrier, which allows host cells to resist invasion by intestinal pathogens. Porcine deltacoronavirus (PDCoV) is an emerging swine enteric virus that causes severe diarrhea in pigs and causes large economic losses to pork producers worldwide. To date, the molecular mechanisms by which PDCoV regulates the function and differentiation of goblet cells and disrupts the intestinal mucosal barrier remain to be determined. Here, we report that in newborn piglets, PDCoV infection disrupts the intestinal barrier: specifically, there is intestinal villus atrophy, crypt depth increases, and tight junctions are disrupted. There is also a significant reduction in the number of goblet cells and the expression of MUC-2. In vitro, using intestinal monolayer organoids, we found that PDCoV infection activates the Notch signaling pathway, resulting in upregulated expression of HES-1 and downregulated expression of ATOH-1 and thereby inhibiting the differentiation of intestinal stem cells into goblet cells. Our study shows that PDCoV infection activates the Notch signaling pathway to inhibit the differentiation of goblet cells and their mucus secretion, resulting in disruption of the intestinal mucosal barrier. IMPORTANCE The intestinal mucosal barrier, mainly secreted by the intestinal goblet cells, is a crucial first line of defense against pathogenic microorganisms. PDCoV regulates the function and differentiation of goblet cells, thereby disrupting the mucosal barrier; however, the mechanism by which PDCoV disrupts the barrier is not known. Here, we report that in vivo, PDCoV infection decreases villus length, increases crypt depth, and disrupts tight junctions. Moreover, PDCoV activates the Notch signaling pathway, inhibiting goblet cell differentiation and mucus secretion in vivo and in vitro. Thus, our results provide a novel insight into the mechanism underlying intestinal mucosal barrier dysfunction caused by coronavirus infection.


Assuntos
Infecções por Coronavirus , Células Caliciformes , Receptores Notch , Doenças dos Suínos , Animais , Coronavirus , Infecções por Coronavirus/patologia , Infecções por Coronavirus/veterinária , Células Caliciformes/citologia , Transdução de Sinais , Suínos , Doenças dos Suínos/patologia , Doenças dos Suínos/virologia , Células-Tronco/citologia , Diferenciação Celular , Receptores Notch/metabolismo
2.
Biophys J ; 2023 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-37838832

RESUMO

The immune response is orchestrated by elaborate protein interaction networks that interweave ligand-mediated receptor reorganization with signaling cascades. While the biochemical processes have been extensively investigated, delineating the biophysical principles governing immune receptor activation has remained challenging due to design limitations of traditional ligand display platforms. These constraints have been overcome by advances in DNA origami nanotechnology, enabling unprecedented control over ligand geometry on configurable scaffolds. It is now possible to systematically dissect the independent roles of ligand stoichiometry, spatial distribution, and rigidity in immune receptor activation, signaling, and cooperativity. In this review, we highlight pioneering efforts in manipulating the ligand presentation landscape to understand immune receptor triggering and to engineer functional immune responses.

3.
Angew Chem Int Ed Engl ; 62(48): e202310920, 2023 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-37842955

RESUMO

Spatiotemporal manipulation of biological processes in living animals using noninvasive, remote-controlled stimuli is a captivating but challenging endeavor. Herein, we present the development of a biocompatible photocatalytic technology termed CAT-NIR, which uses external near infrared light (NIR, 740 nm) to trigger decaging reactions in living mice. The Os(II) terpyridine complex was identified as an efficient NIR photocatalyst for promoting deboronative hydroxylation reactions via superoxide generation in the presence of NIR light, resulting in the deprotection of phenol groups and the release of bioactive molecules under living conditions. The validation of the CAT-NIR system was demonstrated through the NIR-triggered rescue of fluorophores, prodrugs as well as biomolecules ranging from amino acids, peptides to proteins. Furthermore, by combining genetic code expansion and computer-aided screening, CAT-NIR could regulate affibody binding to the cell surface receptor HER2, providing a selective cell tagging technology through external NIR light. In particular, the tissue-penetrating ability of NIR light allowed for facile prodrug activation in living mice, enabling noninvasive, remote-controlled rescue of drug molecules. Given its broad adaptability, this CAT-NIR system may open new opportunities for manipulating the functions of bioactive molecules in living animals using external NIR light with spatiotemporal resolution.


Assuntos
Pró-Fármacos , Camundongos , Animais , Pró-Fármacos/química , Raios Infravermelhos , Proteínas
4.
Chem Soc Rev ; 50(23): 12915-12984, 2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34622260

RESUMO

Smart electronic devices are becoming ubiquitous due to many appealing attributes including portability, long operational time, rechargeability and compatibility with the user-desired form factor. Integration of mobile power sources (MPS) based on photovoltaic technologies with smart electronics will continue to drive improved sustainability and independence. With high efficiency, low cost, flexibility and lightweight features, halide perovskite photovoltaics have become promising candidates for MPS. Realization of these photovoltaic MPS (PV-MPS) with unconventionally extraordinary attributes requires new 'out-of-box' designs. Natural materials have provided promising designing solutions to engineer properties under a broad range of boundary conditions, ranging from molecules, proteins, cells, tissues, apparatus to systems in animals, plants, and humans optimized through billions of years of evolution. Applying bio-inspired strategies in PV-MPS could be biomolecular modification on crystallization at the atomic/meso-scale, bio-structural duplication at the device/system level and bio-mimicking at the functional level to render efficient charge delivery, energy transport/utilization, as well as stronger resistance against environmental stimuli (e.g., self-healing and self-cleaning). In this review, we discuss the bio-inspired/-mimetic structures, experimental models, and working principles, with the goal of revealing physics and bio-microstructures relevant for PV-MPS. Here the emphasis is on identifying the strategies and material designs towards improvement of the performance of emerging halide perovskite PVs and strategizing their bridge to future MPS.


Assuntos
Compostos de Cálcio , Energia Solar , Fontes de Energia Elétrica , Humanos , Óxidos , Titânio
5.
J Am Chem Soc ; 143(11): 4319-4328, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33705120

RESUMO

Black orthorhombic (B-γ) CsSnI3 with reduced biotoxicity and environmental impact and excellent optoelectronic properties is being considered as a promising eco-friendly candidate for high-performing perovskite solar cells (PSCs). A major challenge in a large-scale implementation of CsSnI3 PSCs includes the rapid transformation of Sn2+ to Sn4+ (within a few minutes) under an ambient-air condition. Here, we demonstrate that ambient-air stable B-γ CsSnI3 PSCs can be fabricated by incorporating N,N'-methylenebis(acrylamide) (MBAA) into the perovskite layer and by using poly(3-hexylthiophene) as the hole transporting material. The lone electron pairs of -NH and -CO units of MBAA are designed to form coordination bonding with Sn2+ in the B-γ CsSnI3, resulting in a reduced defect (Sn4+) density and better stability under multiple conditions for the perovskite light absorber. After a modification, the highest power conversion efficiency (PCE) of 7.50% is documented under an ambient-air condition for the unencapsulated CsSnI3-MBAA PSC. Furthermore, the MBAA-modified devices sustain 60.2%, 76.5%, and 58.4% of their initial PCEs after 1440 h of storage in an inert condition, after 120 h of storage in an ambient-air condition, and after 120 h of 1 Sun continuous illumination, respectively.

6.
Int J Mol Sci ; 22(23)2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34884807

RESUMO

This study investigated the effects of l-glutamine (Gln) and/or l-leucine (Leu) administration on sepsis-induced skeletal muscle injuries. C57BL/6J mice were subjected to cecal ligation and puncture to induce polymicrobial sepsis and then given an intraperitoneal injection of Gln, Leu, or Gln plus Leu beginning at 1 h after the operation with re-injections every 24 h. All mice were sacrificed on either day 1 or day 4 after the operation. Blood and muscles were collected for analysis of inflammation and oxidative damage-related biomolecules. Results indicated that both Gln and Leu supplementation alleviated sepsis-induced skeletal muscle damage by reducing monocyte infiltration, calpain activity, and mRNA expression levels of inflammatory cytokines and hypoxia-inducible factor-1α. Furthermore, septic mice treated with Gln had higher percentages of blood anti-inflammatory monocytes and muscle M2 macrophages, whereas Leu treatment enhanced the muscle expressions of mitochondrion-related genes. However, there were no synergistic effects when Gln and Leu were simultaneously administered. These findings suggest that both Gln and Leu had prominent abilities to attenuate inflammation and degradation of skeletal muscles in the early and/or late phases of sepsis. Moreover, Gln promoted the switch of leukocytes toward an anti-inflammatory phenotype, while Leu treatment maintained muscle bioenergetic function.


Assuntos
Anti-Inflamatórios/uso terapêutico , Glutamina/uso terapêutico , Leucina/uso terapêutico , Músculo Esquelético/lesões , Sepse/patologia , Animais , Calpaína/metabolismo , Citocinas/biossíntese , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Inflamação/prevenção & controle , Macrófagos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/fisiologia , Músculo Esquelético/patologia , Estresse Oxidativo/efeitos dos fármacos
7.
Molecules ; 26(3)2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33499307

RESUMO

Cutibacterium acnes (formerly Propionibacterium acnes) is one of the major bacterial species responsible for acne vulgaris. Numerous bioactive compounds from Momordica charantia Linn. var. abbreviata Ser. have been isolated and examined for many years. In this study, we evaluated the suppressive effect of two cucurbitane-type triterpenoids, 5ß,19-epoxycucurbita-6,23-dien-3ß,19,25-triol (Kuguacin R; KR) and 3ß,7ß,25-trihydroxycucurbita-5,23-dien-19-al (TCD) on live C. acnes-stimulated in vitro and in vivo inflammatory responses. Using human THP-1 monocytes, KR or TCD suppressed C. acnes-induced production of interleukin (IL)-1ß, IL-6 and IL-8 at least above 56% or 45%, as well as gene expression of these three pro-inflammatory cytokines. However, a significantly strong inhibitory effect on production and expression of tumor necrosis factor (TNF)-α was not observed. Both cucurbitanes inhibited C. acnes-induced activation of the myeloid differentiation primary response 88 (MyD88) (up to 62%) and mitogen-activated protein kinases (MAPK) (at least 36%). Furthermore, TCD suppressed the expression of pro-caspase-1 and cleaved caspase-1 (p10). In a separate study, KR or TCD decreased C. acnes-stimulated mouse ear edema by ear thickness (20% or 14%), and reduced IL-1ß-expressing leukocytes and neutrophils in mouse ears. We demonstrated that KR and TCD are potential anti-inflammatory agents for modulating C. acnes-induced inflammation in vitro and in vivo.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Cucurbitacinas/química , Cucurbitacinas/farmacologia , Inflamação/tratamento farmacológico , Momordica charantia/química , Triterpenos/química , Triterpenos/farmacologia , Acne Vulgar/tratamento farmacológico , Acne Vulgar/imunologia , Acne Vulgar/microbiologia , Animais , Citocinas/biossíntese , Citocinas/genética , Modelos Animais de Doenças , Glicosídeos/química , Glicosídeos/farmacologia , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Inflamação/imunologia , Inflamação/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Monócitos/metabolismo , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Propionibacteriaceae/patogenicidade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células THP-1
8.
Eur J Nutr ; 59(3): 921-933, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31062080

RESUMO

PURPOSE: Diabetes is a chronic inflammatory disorder resulting in endothelial dysfunction which contributes to peripheral arterial disease and limb ischemia. Leukocytes play critical roles in vascular and tissue remodelling after ischemia. This study investigated the effects of dietary glutamine (GLN) supplementation on immune cell polarization in diabetic mice subjected to limb ischemia. METHODS: Diabetes was induced by an intraperitoneal injection of streptozotocin for 5 consecutive days in C57BL/6J mice. Diabetic mice were fed the AIN-93 diet or an AIN-93 diet in which a part of the casein was replaced by GLN. After 3 weeks of the dietary intervention, mice were subjected to unilateral femoral artery ligation to induce limb ischemia. RESULTS: GLN supplementation enhanced the proportion of anti-inflammatory monocytes and regulatory T cells in the blood. Expression of C-C motif chemokine receptor 5 by activated CD4+ T cells was promoted and prolonged in the GLN-supplemented group. GLN downregulated the percentage of M1 macrophages in muscle tissues which was correlated with lower levels of C-C motif chemokine ligand 2 in plasma. The muscle M1/M2 ratio was also reduced in the GLN group. Gene expression of interleukin-6 was suppressed by GLN supplementation, while expression levels of the peroxisome proliferator-activated receptor γ and myogenic differentiation 1 genes were elevated in post-ischemic muscles. Histological findings also indicated that muscle regeneration was accelerated in the GLN group. CONCLUSIONS: GLN supplementation in diabetic mice may exert more-balanced polarization of CD4+ T cells, monocytes, and macrophages, thus attenuating inflammatory responses and contributing to muscle regeneration after limb ischemia.


Assuntos
Polaridade Celular/efeitos dos fármacos , Diabetes Mellitus Experimental/complicações , Suplementos Nutricionais , Glutamina/farmacologia , Isquemia/dietoterapia , Músculo Esquelético/fisiologia , Animais , Diabetes Mellitus Experimental/imunologia , Dieta/métodos , Modelos Animais de Doenças , Glutamina/administração & dosagem , Glutamina/imunologia , Membro Posterior , Imunidade/efeitos dos fármacos , Imunidade/imunologia , Isquemia/complicações , Isquemia/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/imunologia , Regeneração/efeitos dos fármacos , Regeneração/imunologia
9.
Arch Toxicol ; 94(1): 141-150, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31807802

RESUMO

Inflammatory bowel disease (IBD) is associated with loss of immune tolerance to antigens originating from the diet and from the gut microflora. T cells play crucial roles in the pathogenesis of IBD. Chlorpyrifos (CPF) is one of the most ubiquitous organophosphate pesticides in the world. The aim of the study was to investigate the effects of dietary exposure to CPF on T-cell populations in C57BL/6 mice with dextran sulfate sodium (DSS)-induced colitis. Mice received distilled water containing 3% DSS for 6 days to induce acute colitis, which was then replaced with distilled water for 21 days, allowing progression to chronic inflammation. During the experimental period, mice were given either an AIN-93-based control diet or a CPF diet-containing 7, 17.5, or 35 ppm of CPF. Results showed that dietary exposure to CPF significantly increased circulating neutrophils in colitic mice. CPF-exposed groups had lower percentages of blood and spleen T cells without altering the proportions of CD4+ and CD8+ T-cell subsets. The percentage of blood regulatory T (Treg) cells, as well as splenic expressions of Treg-related genes, were suppressed in CPF-exposed mice. CPF upregulated the colonic gene expression of tumor necrosis factor-α. Meanwhile, plasma haptoglobin, colon weights, and luminal immunoglobulin G levels were higher in CPF-exposed groups. Histopathological analyses also observed that colon injury was more severe in all CPF-exposed mice. These results suggest that dietary exposure to CPF aggravated tissue injuries in mice with DSS-induced chronic colitis by suppressing T-cell populations and Treg polarization.


Assuntos
Colite/induzido quimicamente , Exposição Dietética/efeitos adversos , Linfócitos T Reguladores/efeitos dos fármacos , Acetilcolinesterase/sangue , Animais , Peso Corporal/efeitos dos fármacos , Polaridade Celular/efeitos dos fármacos , Colite/imunologia , Colite/patologia , Sulfato de Dextrana/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Masculino , Camundongos Endogâmicos C57BL , Baço/efeitos dos fármacos , Baço/patologia , Linfócitos T Reguladores/imunologia
10.
Nano Lett ; 19(5): 3313-3320, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-30986075

RESUMO

Fullerene derivative, such as [6,6]-phenyl C61 butyric acid methyl ester (PCBM), is widely used as an electron-transport layer (ETL) in inverted perovskite solar cell (PSC). However, its low electron mobility, complexity in achieving quality film formation, and severe nonradiative recombination at perovskite/PCBM interface due to the large electron capture region, lead to lower efficiency for inverted PSCs compared to the normal structures. Herein, we demonstrate an effective and practical strategy to overcome these challenges. Conjugated n-type polymeric materials are mixed together with PCBM to form a homogeneous bulk-mixed (HBM) continuous film with high electron mobility and suitable energy level. HBM film is found to completely cap the perovskite surface to enhance the electron extraction. The critical electron capture radius of the HBM decreases to 12.52 nm from 14.89 nm of PCBM due to the large relative permittivity, resulting in reduced nonradiative recombination at perovskite/HBM interface. The efficiency of inverted PSCs with HBM ETLs exceeds 20.6% with a high fill factor of 0.82. Further, the stability of devices is improved owing to the high hydrophobicity of the HBM ETLs. Under ambient air condition after 45 days, the efficiency of inverted PSCs based on HBM remains 80% of the initial value. This is significantly higher than the control devices which retain only 48% of the initial value under similar aging conditions. We believe these breakthroughs in improving efficiency and stability of inverted PSCs will expedite their transition.

11.
Nano Lett ; 19(2): 1251-1259, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30694687

RESUMO

Unprecedented conversion efficiency has been demonstrated for perovskite solar cells (PSCs), however, their stability and reliability continue to be challenge. Here, an effective and practical method is demonstrated to overcome the device stability issues in PSCs. A CF4 plasma treatment method is developed that results in the formation of a robust C-F x layer covering the PSC device, thereby, imparting protection during the operation of solar cell. PSCs exposed to fluorination process showed excellent stability against water, light, and oxygen, displaying relatively no noticeable degradation after being dipped into water for considerable time period. The fluorination process did not have any impact on the morphology and electrical property of the top Spiro-OMeTAD layer, resulting in a conversion efficiency of 18.7%, which is identical to that of the pristine PSC. Under the continuous Xe lamp (AM 1.5G, 1 sun) illumination in ambient air for 100 h, the fluorinated PSCs demonstrated 70% of initial conversion efficiency, which is 4000% higher than that of the pristine PSC devices. We believe this breakthrough will have significant impact on the transition of PSCs into real world applications.

12.
Mol Carcinog ; 58(2): 293-304, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30334580

RESUMO

Exportin-T (XPOT) belongs to the RAN-GTPase exportin family that mediates export of tRNA from the nucleus to the cytoplasm. Up-regulation of XPOT indicates poor prognosis in breast cancer patients. However, the correlation between XPOT and hepatocellular carcinoma (HCC) remains unclear. Here, we found that high expression of XPOT in HCC indicated worse prognosis via bioinformatics analysis. Consistently, immunohistochemical staining of 95 pairs of tumors and adjacent normal liver tissues (ANLT) also showed up-regulation of XPOT. Small interfering (si) RNA transfection was used to down-regulate XPOT in HepG2 and 7721 cell lines. Cell Counting Kit-8 (CCK8) assays were performed to analyze cell proliferation. Cell migration and invasion were measured by scratch wound healing assays and migration assays. Subcutaneous xenograft models were using to explore the role of XPOT in tumor formation in vivo. Down-regulation of XPOT significantly inhibited tumor proliferation and invasion in vitro and vivo. Gene set enrichment analysis (GSEA) results indicated that XPOT may affect tumor progression through cell cycle and ubiquitin-mediated proteolysis. Furthermore, knockdown of XPOT caused a block in G0/G1 phase as evidenced by down-regulation of cyclin-dependent kinase 1 (CDK1), cyclin-dependent kinase 2 (CDK2), cyclin-dependent kinase 4 (CDK4), CyclinA1 (CCNA1), CyclinB1 (CCNB1), CyclinB2 (CCNB2), and CyclinE2 (CCNE2) in HCC cells. In conclusion, our findings indicate that XPOT could serve as a novel biomarker for prognoses and a potential therapeutic target for patients with HCC.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Proteínas de Transporte Nucleocitoplasmático/genética , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Regulação para Cima , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Transplante de Neoplasias , Prognóstico , Proteólise , Análise de Sobrevida , Ubiquitina/metabolismo
13.
Mol Carcinog ; 58(4): 603-615, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30556610

RESUMO

Patients with advanced hepatocellular carcinoma (HCC) continue to have a dismal prognosis. Potential biomarkers to determine prognosis and select targeted therapies are urgently needed for patients with HCC. This study aimed to elucidate the role of UCK2 in HCC prognosis and tumor progression. We performed a screen of public databases to identify functional genes associated with HCC tumorigenesis, progression, and outcome. We identified uridine-cytidine kinase 2 (UCK2) as a gene of interest for further study. UCK2 promoting HCC aggressiveness was demonstrated by evaluation of clinical samples, in vitro experiments, in vivo tumorigenicity, and transcript analysis. UCK2 expression was generally elevated in HCC and was significantly correlated with poor survival and inferior clinicopathological characteristics of HCC patients. A multivariate analysis revealed that high UCK2 expression was an independent factor for poor prognosis. In HCC cell lines, UCK2 knockdown suppressed cell migration and invasion and inhibited cell proliferation, while UCK2 overexpression had an opposite effect. Animal model experiments confirmed that knockdown of UCK2 suppressed tumor growth in vivo. The bioinformatics analysis demonstrated that UCK2 might associated with metabolsim, splicesome, and adherens junction. UCK2 is highly associated with HCC malignant behavior and is a potential prognostic predictor for HCC patients in the clinic.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/patologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/patologia , Uridina Quinase/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Movimento Celular , Proliferação de Células , Estudos de Coortes , Progressão da Doença , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas , Uridina Quinase/genética , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Br J Nutr ; 122(6): 657-665, 2019 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-31182172

RESUMO

The present study investigated the effects of glutamine (GLN) pretreatment on CD4+ T cell polarisation and remote kidney injury in mice with gut-derived polymicrobial sepsis. Mice were randomly assigned to three groups: normal control fed with American Institute of Nutrition (AIN)-93G diet and two sepsis groups provided with either AIN-93G-based diet or identical components, except part of casein was replaced by GLN. Mice were given their respective diets for 2 weeks. Then, mice in the sepsis groups were performed with caecal ligation and puncture and were killed 72 h after the surgery. Blood, spleens and kidneys were collected for further examination. The results showed that sepsis resulted in decreased circulating and splenic total T lymphocyte and CD4+ T cell percentages, whereas IL-4-, and forkhead box p3 (Foxp3)-expressing CD4+ T cells percentages were up-regulated. Compared with the sepsis control group, pretreatment with GLN maintained blood T and CD4+ T cells and reduced percentages of IL-4- and Foxp3-expressing CD4+ T cells. Also, a more pronounced activation and increased anti-apoptotic Bcl-2 gene expression of splenic CD4+ T cells were observed. Concomitant with the decreased plasma IL-6, keratinocyte-derived chemokine (KC) levels, the gene expression of KC, macrophage inflammatory protein-2 and renal injury biomarker kidney injury molecule-1 (Kim-1) were down-regulated when GLN was administered. These findings suggest that antecedent of GLN administration elicit a more balanced blood T helper cell polarisation, sustained T cell populations, prevented splenic CD4+ T cell apoptosis and attenuated kidney injury at late phase of polymicrobial sepsis. GLN may have benefits in subjects at risk of abdominal infection.


Assuntos
Linfócitos T CD4-Positivos/citologia , Polaridade Celular , Glutamina/administração & dosagem , Rim/patologia , Sepse/prevenção & controle , Ração Animal , Animais , Linfócitos T CD4-Positivos/metabolismo , Expressão Gênica , Rim/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Sepse/microbiologia , Sepse/patologia , Baço/patologia , Subpopulações de Linfócitos T
15.
Cytokine ; 111: 49-57, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30114629

RESUMO

This study investigated the effects of a fish oil-based lipid emulsion (FO) on local skeletal muscle and remote renal damage at 72 h post-reperfusion in a murine model of hind limb ischemia-reperfusion (IR) injury. Mice were assigned to 1 sham group and 3 IR groups. The IR groups were treated daily with either saline or FO from 3 days prior to limb ischemia till 3 days after reperfusion. Limb IR was induced by applying a 4.5-oz orthodontic rubber band above the left greater trochanter for 120 min followed by band-released reperfusion for 72 h. Mice were then sacrificed to harvest blood, muscle, and kidney for analysis. The results showed that IR injury led to upregulation of pro-inflammatory monocytes in blood, infiltration of leukocytes into injured muscle, and over-expression of pro-inflammatory genes in muscle and kidney tissues. Supplementing FO either before or after IR injury alleviated IR-induced inflammatory gene expressions in muscle and kidney tissues. Furthermore, FO given after IR injury reduced circulating pro-inflammatory monocytes, limited muscle leukocytic infiltration, and improved renal histology. These results suggest that FO may protect the muscles from IR injury. FO given after IR injury can better downregulate the inflammation seen in IR-induced remote kidney injury.


Assuntos
Óleos de Peixe/farmacologia , Membro Posterior/irrigação sanguínea , Nefropatias/metabolismo , Rim/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Emulsões , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/metabolismo , Inflamação/patologia , Rim/patologia , Nefropatias/patologia , Masculino , Camundongos , Distribuição Aleatória , Traumatismo por Reperfusão/patologia
16.
Mediators Inflamm ; 2017: 4929346, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28182087

RESUMO

This study investigated the effects of a fish oil- (FO-) based lipid emulsion on muscle leukocyte chemotaxis and inflammatory responses in a murine model of limb ischemia-reperfusion (IR) injury. Mice were assigned randomly to 1 sham (sham) group, 2 ischemic groups, and 2 IR groups. The sham group did not undergo the ischemic procedure. The mice assigned to the ischemic or IR groups were pretreated intraperitoneally with either saline or FO-based lipid emulsion for 3 consecutive days. The IR procedure was induced by applying a 4.5 oz orthodontic rubber band to the left thigh above the greater trochanter for 120 min and then cutting the band to allow reperfusion. The ischemic groups were sacrificed immediately while the IR groups were sacrificed 24 h after reperfusion. Blood, IR-injured gastrocnemius, and lung tissues were collected for analysis. The results showed that FO pretreatment suppressed the local and systemic expression of several IR-induced proinflammatory mediators. Also, the FO-pretreated group had lower blood Ly6ChiCCR2hi monocyte percentage and muscle M1/M2 ratio than the saline group at 24 h after reperfusion. These findings suggest that FO pretreatment may have a protective role in limb IR injury by modulating the expression of proinflammatory mediators and regulating the polarization of macrophage.


Assuntos
Quimiotaxia de Leucócito/efeitos dos fármacos , Emulsões/uso terapêutico , Óleos de Peixe/uso terapêutico , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Modelos Animais de Doenças , Precondicionamento Isquêmico , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão/imunologia , Traumatismo por Reperfusão/metabolismo
17.
Mediators Inflamm ; 2015: 826319, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26693207

RESUMO

BACKGROUND: This study evaluated the impact of different doses of Astragalus polysaccharides (APS) on the functional status and phenotype of T cells during polymicrobial sepsis. METHODS: On day 1 after cecal ligation and puncture, mice were treated with either saline, 100 (A100), 200 (A200), or 400 mg APS/kg body weight (BW) (A400) by an intraperitoneal injection daily for 4 days. All mice were sacrificed 5 days after the operation. RESULTS: APS treatment reversed the sepsis-induced decrement in the T helper (Th) cell population, and the percentage of activated Th cells also increased in the spleen and Peyer's patches. APS administration downregulated the percentages of circulating Th2 cells and regulatory T cells (Treg), and the percentage of Th17 cells in blood was upregulated in the A400 group. Weight loss and kidney injury were attenuated in the A100 and A200 groups but not in the A400 group at the end of the study. CONCLUSIONS: Treatments with 100 and 200 mg APS/kg BW reduced Treg populations and elicited a more-balanced Th1/Th2 response that consequently attenuated immunosuppression in polymicrobial sepsis. High-dose APS administration led to excessive responses of Th17 cells which may have adverse effects in sepsis-induced organ injury.


Assuntos
Adjuvantes Imunológicos/farmacologia , Astrágalo/química , Polissacarídeos/farmacologia , Sepse/imunologia , Linfócitos T/efeitos dos fármacos , Animais , Polaridade Celular , Interferon gama/análise , Interleucina-4/análise , Rim/patologia , Ativação Linfocitária/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T/fisiologia
18.
Mediators Inflamm ; 2014: 837107, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24891768

RESUMO

BACKGROUND: Migration of T cells into the colon plays a major role in the pathogenesis in inflammatory bowel disease. This study investigated the effects of glutamine (Gln) supplementation on chemokine receptors and adhesion molecules expressed by T cells in mice with dextran sulfate sodium- (DSS-) induced colitis. METHODS: C57BL/6 mice were fed either a standard diet or a Gln diet replacing 25% of the total nitrogen. After being fed the diets for 5 days, half of the mice from both groups were given 1.5% DSS in drinking water to induce colitis. Mice were killed after 5 days of DSS exposure. RESULTS: DSS colitis resulted in higher expression levels of P-selectin glycoprotein ligand- (PSGL-) 1, leukocyte function-associated antigen- (LFA-) 1, and C-C chemokine receptor type 9 (CCR9) by T helper (Th) and cytotoxic T (Tc) cells, and mRNA levels of endothelial adhesion molecules in colons were upregulated. Gln supplementation decreased expressions of PSGL-1, LFA-1, and CCR9 by Th cells. Colonic gene expressions of endothelial adhesion molecules were also lower in Gln-colitis mice. Histological finding showed that colon infiltrating Th cells were less in the DSS group with Gln administration. CONCLUSIONS: Gln supplementation may ameliorate the inflammation of colitis possibly via suppression of T cell migration.


Assuntos
Moléculas de Adesão Celular/metabolismo , Colite/metabolismo , Suplementos Nutricionais , Glutamina/uso terapêutico , Receptores de Quimiocinas/metabolismo , Linfócitos T/metabolismo , Doença Aguda , Administração Oral , Animais , Peso Corporal , Movimento Celular , Colite/fisiopatologia , Colo/efeitos dos fármacos , Colo/patologia , Modelos Animais de Doenças , Heparina/química , Mucosa Intestinal/patologia , Leucócitos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Polissacarídeos/química , Receptores CCR/metabolismo , Linfócitos T/citologia
19.
J Neural Eng ; 21(2)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38457841

RESUMO

Objective.Retinal implants use electrical stimulation to elicit perceived flashes of light ('phosphenes'). Single-electrode phosphene shape has been shown to vary systematically with stimulus parameters and the retinal location of the stimulating electrode, due to incidental activation of passing nerve fiber bundles. However, this knowledge has yet to be extended to paired-electrode stimulation.Approach.We retrospectively analyzed 3548 phosphene drawings made by three blind participants implanted with an Argus II Retinal Prosthesis. Phosphene shape (characterized by area, perimeter, major and minor axis length) and number of perceived phosphenes were averaged across trials and correlated with the corresponding single-electrode parameters. In addition, the number of phosphenes was correlated with stimulus amplitude and neuroanatomical parameters: electrode-retina and electrode-fovea distance as well as the electrode-electrode distance to ('between-axon') and along axon bundles ('along-axon'). Statistical analyses were conducted using linear regression and partial correlation analysis.Main results.Simple regression revealed that each paired-electrode shape descriptor could be predicted by the sum of the two corresponding single-electrode shape descriptors (p < .001). Multiple regression revealed that paired-electrode phosphene shape was primarily predicted by stimulus amplitude and electrode-fovea distance (p < .05). Interestingly, the number of elicited phosphenes tended to increase with between-axon distance (p < .05), but not with along-axon distance, in two out of three participants.Significance.The shape of phosphenes elicited by paired-electrode stimulation was well predicted by the shape of their corresponding single-electrode phosphenes, suggesting that two-point perception can be expressed as the linear summation of single-point perception. The impact of the between-axon distance on the perceived number of phosphenes provides further evidence in support of the axon map model for epiretinal stimulation. These findings contribute to the growing literature on phosphene perception and have important implications for the design of future retinal prostheses.


Assuntos
Retina , Próteses Visuais , Humanos , Estudos Retrospectivos , Retina/fisiologia , Fosfenos , Axônios , Estimulação Elétrica , Percepção
20.
Food Res Int ; 187: 114366, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763646

RESUMO

In recent years, numerous studies have demonstrated the significant potential of non-Saccharomyces yeasts in aroma generation during fermentation. In this study, 134 strains of yeast were isolated from traditional fermented foods. Subsequently, through primary and tertiary screening, 28 strains of aroma-producing non-Saccharomyces yeast were selected for beer brewing. Headspace-solid phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS) and chemometrics were employed to analyze the volatile flavor substances in beer samples fermented using these strains. Chemometric analysis revealed that distinct species of non-Saccharomyces yeast had a unique influence on beer aroma, with strains from the same genus producing more similar flavor profiles. Accordingly, 2,6-nonadienal, 1-pentanol, phenyl ethanol, isoamyl acetate, ethyl caprate, butyl butyrate, ethyl propionate, furfuryl alcohol, phenethyl acetate, ethyl butyrate, ethyl laurate, acetic acid, and 3-methyl-4 heptanone were identified as the key aroma compounds for distinguishing among different non-Saccharomyces yeast species. This work provides useful insights into the aroma-producing characteristics of different non-Saccharomyces yeasts to reference the targeted improvement of beer aroma.


Assuntos
Cerveja , Fermentação , Alimentos Fermentados , Cromatografia Gasosa-Espectrometria de Massas , Odorantes , Microextração em Fase Sólida , Compostos Orgânicos Voláteis , Leveduras , Cerveja/análise , Cerveja/microbiologia , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Alimentos Fermentados/microbiologia , Alimentos Fermentados/análise , Leveduras/isolamento & purificação , Leveduras/metabolismo , Microbiologia de Alimentos
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