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1.
Front Surg ; 11: 1436366, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39072270

RESUMO

Objective: Inconsistent evidence exists regarding the association between intraoperative hypothermia and incidence of surgical site infection (SSI). This study aimed to determine the association between intraoperative hypothermia and SSI. Materials and methods: A systematic review was conducted using Embase, PubMed, and Web of Science to identify observational studies evaluating the risk of SSI in patients with intraoperative hypothermia. The primary outcome measure was the diagnosis of SSI within 30 days of surgery. The pooled risk ratio was estimated using a fixed- or random-effect meta-analysis. Sensitivity analyses were performed to examine the impact of the structural design of preoperative warming on the pooled risk of SSI. Results: Five studies representing 6,002 patients were included in the present meta-analysis. Intraoperative hypothermia was not associated with SSI risk in patients (HR = 1.22, 95% CI: 0.95-2.24, P = 0.119). The pooled hazard ratio showed that intraoperative hypothermia did not result in a higher risk of SSI. Conclusions: Intraoperative hypothermia was not associated with the risk of SSI. Further studies using objective exposure measurements are required to confirm these results.

2.
Front Plant Sci ; 15: 1273774, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38352646

RESUMO

Introduction: The panicle fertilization strategy for japonica and indica rice under wheat straw return (SR) has not been updated, especially on the elaboration of their impacts on spikelet differentiation and degeneration. This study aimed to verify the hypothesis that SR increases spikelet number by reducing spikelet degeneration and to explore the possibility of simplifying panicle fertilization. Methods: In three consecutive years, four varieties of japonica and indica rice were field-grown in Yangzhou, Jiangsu Province, China. Six panicle fertilization rates and split treatments were applied to SR and no straw return (NR) conditions. Results: The results showed that SR promoted rice yield significantly by 3.77%, and the highest yields were obtained under the T2 (split panicle fertilization at the panicle initiation (PI) and spikelet primordium differentiation (SPD) stages) and T1 (panicle fertilization only at the PI stage) treatments, for indica and japonica rice, respectively. Correlation and path analysis revealed that the number of spikelets per panicle was the most attributable to yield variation. SR significantly increased the concentration of alkali hydrolyzable N in the soil 40 days after rice transplantation, significantly increased the nitrogen accumulation per stem (NA) during the SPD-pollen mother cell meiosis (PMC) stage, and increased the brassinosteroids level in the young panicles at the PMC stage. SR also reduced the degeneration rate of spikelets (DRS) and increased the number of surviving spikelets (NSS). The dry matter accumulation per stem was more important to increasing the NA in japonica rice at the PMC stage, whereas NA was more affected by the N content than the dry matter accumulation in indica rice. In japonica rice, panicle N application once only at the PI stage combined with the N released from SR was enough to improve the plant N content, reduce the DRS, and increase the NSS. For indica rice, split application of N panicle fertilization at both the PI and SPD stages was still necessary to achieve a maximum NSS. Discussion: In conclusion, under wheat SR practice, panicle fertilization could be simplified to once in japonica rice with a significant yield increase, whereas equal splits might still be optimal for indica rice.

3.
J Neuroinflammation ; 20(1): 256, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37941008

RESUMO

BACKGROUND: Efferocytosis is a process that removes apoptotic cells and cellular debris. Clearance of these cells alleviates neuroinflammation, prevents the release of inflammatory molecules, and promotes the production of anti-inflammatory cytokines to help maintain tissue homeostasis. The underlying mechanisms by which this occurs in the brain after injury remain ill-defined. METHODS: We used GFP bone marrow chimeric knockout (KO) mice to demonstrate that the axon guidance molecule EphA4 receptor tyrosine kinase is involved in suppressing MERTK in the brain to restrict efferocytosis of resident microglia and peripheral-derived monocyte/macrophages. RESULTS: Single-cell RNAseq identified MERTK expression, the primary receptor involved in efferocytosis, on monocytes, microglia, and a subset of astrocytes in the damaged cortex following brain injury. Loss of EphA4 on infiltrating GFP-expressing immune cells improved functional outcome concomitant with enhanced efferocytosis and overall protein expression of p-MERTK, p-ERK, and p-Stat6. The percentage of GFP+ monocyte/macrophages and resident microglia engulfing NeuN+ or TUNEL+ cells was significantly higher in KO chimeric mice. Importantly, mRNA expression of Mertk and its cognate ligand Gas6 was significantly elevated in these mice compared to the wild-type. Analysis of cell-specific expression showed that p-ERK and p-Stat6 co-localized with MERTK-expressing GFP + cells in the peri-lesional area of the cortex following brain injury. Using an in vitro efferocytosis assay, co-culturing pHrodo-labeled apoptotic Jurkat cells and bone marrow (BM)-derived macrophages, we demonstrate that efferocytosis efficiency and mRNA expression of Mertk and Gas6 was enhanced in the absence of EphA4. Selective inhibitors of ERK and Stat6 attenuated this effect, confirming that EphA4 suppresses monocyte/macrophage efferocytosis via inhibition of the ERK/Stat6 pathway. CONCLUSIONS: Our findings implicate the ERK/Stat6/MERTK axis as a novel regulator of apoptotic debris clearance in brain injury that is restricted by peripheral myeloid-derived EphA4 to prevent the resolution of inflammation.


Assuntos
Orientação de Axônios , Lesões Encefálicas , Camundongos , Animais , c-Mer Tirosina Quinase/metabolismo , Apoptose , Fagocitose/fisiologia , Camundongos Knockout , RNA Mensageiro , Fator de Transcrição STAT6/metabolismo
5.
Photobiomodul Photomed Laser Surg ; 40(7): 507-515, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35867122

RESUMO

Objective: The purpose of this study is to investigate the crystal structure of bacteria-contaminated bovine dentin after Er:YAG laser irradiation at various energy densities from macroscale, microscale, and nanoscale. Background: Er:YAG laser can change the morphology and chemical components of dentin. Few preliminary researchers investigate the laser effect on crystal in dentin tissue. Methods: Twenty dentin specimens from bovine incisors were cocultured with S. mutans (UA 159) and divided into four groups with diverse Er:YAG laser irradiation energy (0, 6.37, 12.73, 19.11 J/cm2). The ultrastructure of dentin before and after laser irradiation was investigated with nanoanalytical electron microscopy. X-ray diffraction provided the information of lattice parameters in dentin. The morphology of dentin was observed by scanning electron microscopy. High-resolution transmission electron microscope images and selected-area electron diffraction patterns were obtained for characterizing crystal domain size, structure, and microenvironment of dentin. Results: The combination of these methods disclosed that there exist mineralized, demineralized, and remineralized dentin in the bacteria-invaded dentin and can be feasibly recognized using morphological features. Laser treatments influence hydroxyapatite (HAp) crystals in dentin tissue in different ways: needle HAp in mineralized dentin tissue keeps intact with laser irradiation of no higher than 19.11 J/cm2; laser irradiation improves the crystallinity of lamella HAp by domain growth and rearranges its growth orientations. Conclusions: We report an unprecedented presence of remineralization zone consisting of lamella HAp crystals with distinct high-index planes. These findings have broad implications on the role of laser operation in driving biomineralization and shed new insights into a possible relationship between laser irradiation and remineralization.


Assuntos
Dentina , Lasers de Estado Sólido , Animais , Bactérias , Bovinos , Dentina/efeitos da radiação , Microscopia Eletrônica de Varredura
6.
Radiol Case Rep ; 17(8): 2802-2805, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35694636

RESUMO

Wilms' tumor, also called nephroblastoma, is an extremely uncommon kidney tumor of adulthood. We reported a adult man with a left kidney mass diagnosed as Wilms' tumor. Case presentation: A 25-year-old man was hospitalized due to injury of the anterior cruciate ligament of the right knee. Preoperative imaging accidentally revealed a mass measuring 53 × 46 mm involving the middle and lower segments of the left kidney without evidence supporting the invasion of the surrounding structures or metastasis. The patient didn't show any symptom commonly occurred in Wilms' tumor, such as flank pain or hematuria. After nephrectomy, the diagnosis of adult Wilms' tumor was confirmed based on the tumor morphology and immunohistochemical findings. Conclusion: In adult patients without any clinical manifestations or favorable imaging findings for low-stage renal cell carcinoma, the diagnosis of Wilms' tumor should be taken into consideration.

7.
Biophys J ; 121(9): 1593-1609, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35398020

RESUMO

The lipid bilayer of eukaryotic cells' plasma membrane is almost impermeable to small ions and large polar molecules, but its miniscule basal permeability in intact cells is poorly characterized. This report describes the intrinsic membrane permeability of A549 cells toward the charged molecules propidium (Pr2+) and ATP4-. Under isotonic conditions, we detected with quantitative fluorescence microscopy, a continuous low-rate uptake of Pr (∼150 × 10-21 moles (zmol)/h/cell, [Pr]o = 150 µM, 32°C). It was stimulated transiently but strongly by 66% hypotonic cell swelling reaching an influx amplitude of ∼1500 (zmol/h)/cell. The progressive Pr uptake with increasing [Pr]o (30, 150, and 750 µM) suggested a permeation mechanism by simple diffusion. We quantified separately ATP release with custom wide-field-of-view chemiluminescence imaging. The strong proportionality between ATP efflux and Pr2+ influx during hypotonic challenge, and the absence of stimulation of transmembrane transport following 300% hypertonic shock, indicated that ATP and Pr travel the same conductive pathway. The fluorescence images revealed a homogeneously distributed intracellular uptake of Pr not consistent with high-conductance channels expressed at low density on the plasma membrane. We hypothesized that the pathway consists of transiently formed water pores evenly spread across the plasma membrane. The abolition of cell swelling-induced Pr uptake with 500 µM gadolinium, a known modulator of membrane fluidity, supported the involvement of water pores whose formation depends on the membrane fluidity. Our study suggests an alternative model of a direct permeation of ATP (and other molecules) through the phospholipid bilayer, which may have important physiological implications.


Assuntos
Trifosfato de Adenosina , Água , Células A549 , Trifosfato de Adenosina/metabolismo , Transporte Biológico/fisiologia , Humanos , Propídio
8.
JCI Insight ; 7(8)2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35298439

RESUMO

While critical for neurotransmitter synthesis, 14-3-3 proteins are often assumed to have redundant functions due to their ubiquitous expression, but despite this assumption, various 14-3-3 isoforms have been implicated in regulating metabolism. We previously reported contributions of 14-3-3ζ in ß cell function, but these studies were performed in tumor-derived MIN6 cells and systemic KO mice. To further characterize the regulatory roles of 14-3-3ζ in ß cell function, we generated ß cell-specific 14-3-3ζ-KO mice. Although no effects on ß cell mass were detected, potentiated glucose-stimulated insulin secretion (GSIS), mitochondrial function, and ATP synthesis were observed. Deletion of 14-3-3ζ also altered the ß cell transcriptome, as genes associated with mitochondrial respiration and oxidative phosphorylation were upregulated. Acute 14-3-3 protein inhibition in mouse and human islets recapitulated the enhancements in GSIS and mitochondrial function, suggesting that 14-3-3ζ is the critical isoform in ß cells. In dysfunctional db/db islets and human islets from type 2 diabetic donors, expression of Ywhaz/YWHAZ, the gene encoding 14-3-3ζ, was inversely associated with insulin secretion, and pan-14-3-3 protein inhibition led to enhanced GSIS and mitochondrial function. Taken together, this study demonstrates important regulatory functions of 14-3-3ζ in the regulation of ß cell function and provides a deeper understanding of how insulin secretion is controlled in ß cells.


Assuntos
Células Secretoras de Insulina , Proteínas 14-3-3/metabolismo , Proteínas 14-3-3/farmacologia , Animais , Glucose/metabolismo , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Camundongos , Mitocôndrias/metabolismo
9.
Oncogene ; 41(14): 2122-2136, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35190642

RESUMO

Glioblastomas (GBMs) preferentially generate acetyl-CoA from acetate as a fuel source to promote tumor growth. O-GlcNAcylation has been shown to be elevated by increasing O-GlcNAc transferase (OGT) in many cancers and reduced O-GlcNAcylation can block cancer growth. Here, we identify a novel mechanism whereby OGT regulates acetate-dependent acetyl-CoA and lipid production by regulating phosphorylation of acetyl-CoA synthetase 2 (ACSS2) by cyclin-dependent kinase 5 (CDK5). OGT is required and sufficient for GBM cell growth and regulates acetate conversion to acetyl-CoA and lipids. Elevating O-GlcNAcylation in GBM cells increases phosphorylation of ACSS2 on Ser-267 in a CDK5-dependent manner. Importantly, we show that ACSS2 Ser-267 phosphorylation regulates its stability by reducing polyubiquitination and degradation. ACSS2 Ser-267 is critical for OGT-mediated GBM growth as overexpression of ACSS2 Ser-267 phospho-mimetic rescues growth in vitro and in vivo. Importantly, we show that pharmacologically targeting OGT and CDK5 reduces GBM growth ex vivo. Thus, the OGT/CDK5/ACSS2 pathway may be a way to target altered metabolic dependencies in brain tumors.


Assuntos
Glioblastoma , Acetato-CoA Ligase/metabolismo , Acetatos/metabolismo , Acetatos/farmacologia , Linhagem Celular Tumoral , Humanos , N-Acetilglucosaminiltransferases/metabolismo , Fosforilação
10.
Life (Basel) ; 11(7)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34357072

RESUMO

The lytic release of ATP due to cell and tissue injury constitutes an important source of extracellular nucleotides and may have physiological and pathophysiological roles by triggering purinergic signalling pathways. In the lungs, extracellular ATP can have protective effects by stimulating surfactant and mucus secretion. However, excessive extracellular ATP levels, such as observed in ventilator-induced lung injury, act as a danger-associated signal that activates NLRP3 inflammasome contributing to lung damage. Here, we discuss examples of lytic release that we have identified in our studies using real-time luciferin-luciferase luminescence imaging of extracellular ATP. In alveolar A549 cells, hypotonic shock-induced ATP release shows rapid lytic and slow-rising non-lytic components. Lytic release originates from the lysis of single fragile cells that could be seen as distinct spikes of ATP-dependent luminescence, but under physiological conditions, its contribution is minimal <1% of total release. By contrast, ATP release from red blood cells results primarily from hemolysis, a physiological mechanism contributing to the regulation of local blood flow in response to tissue hypoxia, mechanical stimulation and temperature changes. Lytic release of cellular ATP may have therapeutic applications, as exemplified by the use of ultrasound and microbubble-stimulated release for enhancing cancer immunotherapy in vivo.

11.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(1): 1-7, 2020 Jan 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-32132291

RESUMO

OBJECTIVES: To investigate the effect of icariin (ICA) on early ß-defensin-2 and T cell subsets in rats after tracheotomy. METHODS: A total of 54 SPF male Sprague-Dawley rats were randomly divided into a normal control group (group A), a model group (group B), and a model+ICA treatment group (group C), with 18 rats in each group. A tracheotomy intubation model of the B and C group was prepared. After 6 h of surgery, ICA intervention was given to group C. Groups A and B were given the same amount of normal saline. Lung tissue, alveolar lavage fluid and peripheral blood were taken at 24 h, 72 h and 168 h, respectively. The expression of rat ß-defensin-2 mRNA in lung tissue was detected by RT-PCR. The content of ß-defensin-2 in alveolar lavage fluid and peripheral blood serum was detected by ELISA. The content of peripheral blood T cell subsets (CD3+, CD4+, CD8+) was detected by flow cytometry, and the ratio of CD4+/CD8+ was calculated. RESULTS: After tracheotomy, the levels of ß-defensin-2 mRNA and ß-defensin-2 in lung tissue from the group B were increased significantly at 24 h, then they were decreased gradually, and decreased most significantly at 168 h (P<0.05). The content of ß-defensin-2 in peripheral blood of group B decreased gradually, and the content of ß-defensin-2 in 168 h was significantly lower than that in 24 h (P<0.05), but there was no significant difference between group B and group A (P>0.05). The level of CD3+ T cells in peripheral blood was significantly lower than that in the group A (P<0.05), but their was no significant difference in CD4+ and CD8+ T cells compared with group A (P>0.05). After ICA intervention in group C: lung tissue, alveolar lavage fluid, peripheral blood serum ß-defensin-2 content, and peripheral blood CD3+ and CD4+ T cell levels were gradually increased, significantly higher than those in the group B (P<0.05). CD8+ T cell level was significantly lower than that in the group A at 24 h (P<0.05), the CD4+/CD8+ ratio was significantly higher at 168 h than those in the group A or B (both P<0.01). CONCLUSIONS: ICA can improve the early lung immune function in rats with tracheotomy, which might be related to up-regulation of ß-defensin-2 in lung tissue and alveolar lavage fluid, concomitant with increases in CD3+ and CD4+ T cells and CD4+/CD8+ ratio in peripheral blood while reduction in CD8+ cells.


Assuntos
Subpopulações de Linfócitos T , Animais , Flavonoides , Masculino , Ratos , Ratos Sprague-Dawley , Traqueotomia , beta-Defensinas
12.
Am J Physiol Lung Cell Mol Physiol ; 318(1): L49-L58, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31596106

RESUMO

Extracellular ATP and its metabolites are potent paracrine modulators of lung alveolar cell function, including surfactant secretion and fluid transport, but the sources and mechanism of intra-alveolar ATP release remain unclear. To determine the contribution of gas-exchanging alveolar type 1 (AT1) and surfactant-secreting type 2 (AT2) cells to stretch-induced ATP release, we used quantitative real-time luminescence ATP imaging and rat primary alveolar cells cultured on silicon substrate for 2-7 days. When cultured on solid support, primary AT2 cells progressively transdifferentiated into AT1-like cells with ~20% of cells showing AT1 phenotype by day 2-3 (AT2:AT1 ≈ 4:1), while on day 7, the AT2:AT1 cell ratio was reversed with up to 80% of the cells displaying characteristics of AT1 cells. Stretch (1 s, 5-35%) induced ATP release from AT2/AT1 cell cultures, and it was highest on days 2 and 3 but declined in older cultures. ATP release tightly correlated with the number of remaining AT2 cells in culture, consistent with ~10-fold lower ATP release by AT1 than AT2 cells. ATP release was unaffected by inhibitors of putative ATP channels carbenoxolone and probenecid but was significantly diminished in cells loaded with calcium chelator BAPTA. These pharmacological modulators had similar effects on stretch-induced intracellular Ca2+ responses measured by Fura2 fluorescence. The study revealed that AT2 cells are the primary source of stretch-induced ATP release in heterocellular AT2/AT1 cell cultures, suggesting similar contribution in intact alveoli. Our results support a role for calcium-regulated mechanism but not ATP-conducting channels in ATP release by alveolar epithelial cells.


Assuntos
Trifosfato de Adenosina/metabolismo , Células Epiteliais Alveolares/metabolismo , Pulmão/metabolismo , Alvéolos Pulmonares/metabolismo , Sistemas de Secreção Tipo II/metabolismo , Animais , Cálcio/metabolismo , Células Cultivadas , Masculino , Ratos , Ratos Sprague-Dawley
13.
PLoS One ; 14(7): e0219205, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31269062

RESUMO

In the rat, oxytocin (OT) produces dose-dependent diuretic and natriuretic responses. Post-translational enzymatic conversion of the OT biosynthetic precursor forms both mature and C-terminally extended peptides. The plasma concentrations of these C-terminally extended peptides (OT-G; OT-GK and OT-GKR) are elevated in newborns and pregnant rats. Intravenous injection of OT-GKR to rats inhibits diuresis, whereas injection of amidated OT stimulates diuresis. Since OT and OT-GKR show different effects on the urine flow, we investigated whether OT-GKR modulates renal action by inhibition of the arginine-vasopressin (AVP) receptor V2 (V2R), the receptor involved in renal water reabsorption. Experiments were carried out in the 8-week-old Wistar rats receiving intravenous (iv) injections of vehicle, OT, OT-GKR or OT+OT-GKR combination. OT (10 µmol/kg) increased urine outflow by 40% (P<0.01) and sodium excretion by 47% (P<0.01). Treatment with OT-GKR (10 µmol/kg) decreased diuresis by 50% (P<0.001), decreased sodium excretion by 50% (P<0.05) and lowered potassium by 42% (P<0.05). OT antagonist (OTA) reduced diuresis and natriuresis exerted by OT, whereas the anti-diuretic effect of OT-GKR was unaffected by OTA. The treatment with V2R antagonist (V2A) in the presence and absence of OT induced diuresis, sodium and potassium outflow. V2A in the presence of OT-GKR only partially increased diuresis and natriuresis. Autoradiography and molecular docking analysis showed potent binding of OT-GKR to V2R. Finally, the release of cAMP from CHO cells overexpressing V2 receptor was induced by low concentration of AVP (EC50:4.2e-011), at higher concentrations of OT (EC50:3.2e-010) and by the highest concentrations of OT-GKR (EC50:1.1e-006). OT-GKR potentiated cAMP release when combined with AVP, but blocked cAMP release when combined with OT. These results suggest that OT-GKR by competing for the OT renal receptor (OTR) and binding to V2R in the kidney, induces anti-diuretic, anti-natriuretic, and anti-kaliuretic effects.


Assuntos
Diurese , Natriurese , Ocitocina/metabolismo , Animais , Autorradiografia , Ligação Competitiva , Células CHO , Linhagem Celular , Cricetinae , Cricetulus , AMP Cíclico/metabolismo , Eletrólitos/metabolismo , Humanos , Rim/metabolismo , Simulação de Acoplamento Molecular , Peptídeos/metabolismo , Ratos , Ratos Wistar , Receptores de Vasopressinas/metabolismo , Micção , Vasopressinas/metabolismo
14.
Am J Physiol Cell Physiol ; 317(3): C566-C575, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31216191

RESUMO

Although several mechanical stressors promote ATP secretion from eukaryotic cells, few mechanosensitive pathways for ATP release have been precisely characterized and none have been clearly identified. To facilitate progress, we report here a wide field of view (∼20 × 20 mm sample area) imaging technique paired with a quantitative image analysis to accurately map the dynamics of ATP release from a cell population. The approach has been tested on A549 cells stretched at high initial strain rate (2-5 s-1) or swelled by hypotonic shock. The amount of ATP secreted in response to a series of five graded stretch pulses (5-37% linear deformation, 1-s duration at 25°C) changed nonmonotonically with respect to strain amplitude and was inhomogeneous across the cell monolayer. In a typical experiment, extracellular ATP density averaged 250 fmol/mm2, but the area of detectable signal covered only ∼40% of the cells. In some areas, ATP accumulation peaked around 900 fmol/mm2, which corresponded to an estimated concentration of 4.5 µM. The total amount of ATP released from the combined stretch pulses reached 384 ± 224 pmol/million cells (n = 4). Compared with stretch, hypotonic shock (50%, 30°C) elicited a more homogeneous ATP secretion from the entire cell population but at a lower yield totaling 28 ± 12 pmol/million cells (n = 4). The quantitative extracellular ATP mapping of several thousand cells at once, with this wide field of view imaging system, will help identify ATP release pathways by providing unique insights on the dynamics and inhomogeneities of the cellular ATP secretion that are otherwise difficult to assess within the smaller field of view of a microscope.


Assuntos
Trifosfato de Adenosina/metabolismo , Membrana Celular/fisiologia , Membrana Celular/ultraestrutura , Imagem Molecular/métodos , Pressão Osmótica/fisiologia , Estresse Mecânico , Células A549 , Humanos , Microscopia Eletrônica/métodos
15.
Curr Top Membr ; 83: 45-76, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31196610

RESUMO

Extracellular ATP and other nucleotides are important autocrine/paracrine mediators that stimulate purinergic receptors and regulate diverse processes in the normal lungs. They are also associated with pathogenesis of a number of respiratory diseases and clinical complications including acute respiratory distress syndrome and ventilator induced lung injury. Mechanical forces are major stimuli for cellular ATP release but precise mechanisms responsible for this release are still debated. The present review intends to provide the current state of knowledge of the mechanisms of ATP release in the lung. Putative pathways of the release, including the contribution of cell membrane injury and cell lysis are discussed addressing their strength, weaknesses and missing evidence that requires future study. We also provide an overview of the recent technical advances in studying cellular ATP release in vitro and ex vivo. Special attention is given to new insights into lung ATP release obtained with the real-time luminescence ATP imaging. This includes recent data on stretch-induced mechanosensitive ATP release in a model and primary cells of lung alveoli in vitro as well as inflation-induced ATP release in airspaces and pulmonary blood vessels of lungs, ex vivo.


Assuntos
Trifosfato de Adenosina/metabolismo , Pulmão/diagnóstico por imagem , Pulmão/metabolismo , Fenômenos Mecânicos , Imagem Óptica , Animais , Fenômenos Biomecânicos , Humanos , Pulmão/citologia , Fatores de Tempo
16.
Am J Transl Res ; 11(1): 199-209, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30787979

RESUMO

Inflammation and oxidative stress are considered major factors in the pathogenesis of ischemic stroke. Increasing evidence has demonstrated that Schizandrin A (Sch A), a lignin compound isolated from Schisandra chinesnesis, exhibits prominent anti-inflammatory and antioxidant activities. In this study, we investigated the anti-inflammatory and antioxidant effects of Sch A against cerebral ischemia/reperfusion (I/R) injury as well as the underlying molecular mechanisms. Sch A treatment significantly improved the neurological score and reduced infarct volume 24 h after reperfusion. It dose-dependently inhibited the expression of cyclooxygenase-2 and inducible nitric oxide synthase, reduced the release of pro-inflammatory cytokines (tumor necrosis factor-α interleukin [IL]-1ß and IL-6), and increased anti-inflammatory cytokines (transforming growth factor-ß and interleukin-10). Furthermore, it increased the activity of superoxide dismutase and catalase, decreased reactive oxygen species production and 4-hydroxynonenal and 8-hydroxy-2'-deoxyguanosine levels. Transcription of nuclear factor erythroid 2-related factor 2 (Nrf2) and downstream genes (heme oxygenase-1 and NAD[P]H: quinone oxidoreductase 1) increased. Knockdown of Nrf2 by siRNA inhibited the neuroprotective effects of Sch A. In addition, Sch A increased phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) both in vivo and in vitro. Activation of the Nrf2 pathway as well as the protective effects of Sch A in an oxygen and glucose deprivation-induced injury model was abolished by AMPK knockdown. Our study indicates that Sch A protects against cerebral I/R injury by suppressing inflammation and oxidative stress, and that this effect is regulated by the AMPK/Nrf2 pathway.

17.
Biotechnol Appl Biochem ; 66(2): 247-253, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30548933

RESUMO

The present study aimed to investigate the protective effects of salidroside (SAL) on 1-methyl-4-phenylpyridinium (MPP+ )-induced PC12 cell model for Parkinson's disease. PC12 cells were pretreated with SAL in different concentrations and then exposed to MPP+ . To evaluate the effects of SAL on cytotoxicity, the survival rate was tested by the 3-(4,5-dimethylthiazol-2-yl)-2,5-dimethyltetrazolium bromide (MTT) assay and the apoptosis was tested via flow cytometry and Western blot. Reactive oxygen species (ROS), glutathione (GSH), and malondialdehyde (MDA) were detected to analyze the effects of SAL on oxidative stress. The mRNA and protein levels of inflammatory factors TNF-α and IL-1ß were also determined by real-time quantitative polymerase chain reaction and Western blot. Pretreatment with SAL effectively relieved the MPP+ cytotoxic effects and decreased the release of ROS production and inflammatory cytokines. SAL also inhibited apoptosis, suppressed MDA activity, and increased GSH levels in MPP+ -treated PC12 cells. Moreover, the expression levels of caspase-9, caspase-3, and Bax were significantly decreased in the SAL treatment groups compared with the MPP+ group, whereas Bcl-2 expression was significantly increased in the SAL treatment groups. In summary, the overall results suggested that SAL have neuroprotective effects on the MPP+ -induced PC12 cell model by inhibiting inflammation, oxidative stress, and cell apoptosis. SAL may be a potential active product to protect against Parkinson's disease.


Assuntos
Apoptose/efeitos dos fármacos , Glucosídeos/farmacologia , Intoxicação por MPTP/prevenção & controle , Estresse Oxidativo/efeitos dos fármacos , Fenóis/farmacologia , Animais , Caspase 3/metabolismo , Caspase 9/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Inflamação/patologia , Inflamação/prevenção & controle , Intoxicação por MPTP/metabolismo , Intoxicação por MPTP/patologia , Células PC12 , Ratos , Proteína X Associada a bcl-2/metabolismo
18.
Biomed Res Int ; 2018: 8359013, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30581869

RESUMO

OBJECTIVE: Oxidant stress plays an important role in the development of diabetic cardiomyopathy. Previously we reported that Astragalus polysaccharides (APS) rescued heart dysfunction and cardinal pathological abnormalities in diabetic mice. In the current study, we determined whether the effect of APS on diabetic cardiomyopathy was associated with its impact on oxidant stress. METHODS: Db/db diabetic mice were employed and administered with APS. The hematodynamics, cardiac ultra-structure, apoptosis, and ROS formation of myocardium were assessed. The cardiac protein expression of apoptosis target genes (Bax, Bcl-2, and caspase-3) and oxidation target genes (Gpx, SOD2, t/p-JNK, catalase, t/p-p38 MAPK, and t/p-ERK) were evaluated, respectively. RESULTS: APS therapy improved hematodynamics and cardinal ultra-structure with reduced apoptosis and ROS formation in db/db hearts. In addition, APS therapy inhibited the protein expression of apoptosis target genes (Bax, Bcl-2, and caspase-3) and regulated the protein expression of oxidation target genes (enhancing Gpx, SOD2, and catalase, while reducing t/p-JNK, t/p-ERK, and t/p-p38 MAPK) in db/db hearts. CONCLUSION: Our findings suggest that APS has benefits in diabetic cardiomyopathy, which may be partly associated with its impact on cardiac oxidant stress.


Assuntos
Astrágalo/química , Cardiomiopatias Diabéticas/tratamento farmacológico , Miócitos Cardíacos/efeitos dos fármacos , Oxidantes/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Diabetes Mellitus Experimental/metabolismo , Cardiomiopatias Diabéticas/metabolismo , Camundongos , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo
19.
Mol Ther Nucleic Acids ; 12: 578-590, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-30195794

RESUMO

Doxorubicin is a widely used anthracycline-based anti-tumor agent for both solid and liquid tumors. Mounting evidence has demonstrated that microRNAs (miRNAs) are involved in chemoresistance and tumorigenesis. However, the roles of microRNA-501-5p (miR-501) in doxorubicin resistance and gastric cancer cell proliferation and invasion are still not fully understood. In this study, we identified that BLID (BH3-like motif-containing protein, cell death inducer) was directly regulated by miR-501 at the post-transcriptional level in multiple gastric cancer cell lines. Endogenous miR-501 was higher, whereas BLID was lower, in doxorubicin-resistant gastric cancer SGC7901/ADR cells compared with their parental SGC7901 cells. miR-501 suppressed gastric cancer cell apoptosis, induced resistance to doxorubicin, and enhanced cell proliferation, migration, and invasion. Subcutaneous injection of miR-501 lentivirus-infected SGC7901 cells resulted in rapid growth of xenograft tumors and resistance to doxorubicin treatment, unlike injection of negative miRNA lentivirus-infected SGC7901 cells. This is achieved at least partially by directly targeting BLID and subsequent inactivation of caspase-9 and caspase-3 and phosphorylation of Akt. Taken together, miR-501 induces doxorubicin resistance and enhances the tumorigenesis of gastric cancer cells by suppressing BLID. miR-501 might be a potential target for doxorubicin resistance and gastric cancer therapy.

20.
Drug Des Devel Ther ; 12: 997-1008, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29731607

RESUMO

BACKGROUND: 4-Amino-2-trifluoromethyl-phenyl retinate (ATPR), a novel retinoid derivative, inhibits proliferation and induces differentiation in many cancer cells. In this study, the inhibitory effects of ATPR on the proliferation, invasion, and migration of breast cancer (BC) cells, and the relationship between ATPR and the expression of the intracellular lipid-binding proteins CRABP2 and FABP5 were investigated. METHODS: CRABP2 and FABP5 expression was evaluated in infiltrating breast-infiltrating ductal carcinoma(BIDC) and benign breast fibroma (BBF) by immunohistochemistry and in MCF-7, MDA-MB-231, MDA-MB-435, and MDA-MB-453 cells by immunofluorescence. The inhibition of proliferation by ATPR in these cells was detected by MTT. After downregulation and upregulation of CRABP2 and FABP5 in MCF-7 or MDA-MB-231 cells using siRNA and plasmids, the effect of ATPR on proliferation was detected by MTT and real-time cell analysis, and the effects of ATPR on the invasion and migration of MDA-MB-231 cells were detected using a Boyden chamber assay and a wound healing assay. RESULTS: CRABP2 expression was moderately or strongly positive in BIDC and BBF. FABP5 expression was also moderately or strongly positive in BIDC, but weakly positive or negative in BBF. CRABP2 and FABP5 were highly expressed in MCF-7 cells, moderately expressed in MDA-MB-453 cells, and weakly expressed in MDA-MB-435 and MDA-MB-231 cells. ATPR inhibited proliferation more strongly in MCF-7 cells than in other cells. The inhibition of proliferation by ATPR depended on an increase in CRABP2, but not FABP5 expression. A decrease in FABP5 could inhibit the invasion and migration of BC cells. CONCLUSION: These findings indicate that ATPR might inhibit proliferation by upregulating CRABP2, and inhibit invasion and migration by downregulating FABP5 in BC cells. These findings may facilitate the use of differentiation therapy in BC.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Proteínas de Ligação a Ácido Graxo/metabolismo , Receptores do Ácido Retinoico/metabolismo , Retinoides/farmacologia , Antineoplásicos/química , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Proteínas de Ligação a Ácido Graxo/antagonistas & inibidores , Proteínas de Ligação a Ácido Graxo/genética , Feminino , Inativação Gênica/efeitos dos fármacos , Humanos , Estrutura Molecular , RNA Interferente Pequeno/farmacologia , Receptores do Ácido Retinoico/antagonistas & inibidores , Receptores do Ácido Retinoico/genética , Retinoides/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Cicatrização/efeitos dos fármacos
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