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1.
Materials (Basel) ; 16(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37959457

RESUMO

Dental implants have revolutionised restorative dentistry, offering patients a natural-looking and durable solution to replace missing or severely damaged teeth. Titanium and its alloys have emerged as the gold standard among the various materials available due to their exceptional properties. One of the critical advantages of titanium and its alloys is their remarkable biocompatibility which ensures minimal adverse reactions within the human body. Furthermore, they exhibit outstanding corrosion resistance ensuring the longevity of the implant. Their mechanical properties, including hardness, tensile strength, yield strength, and fatigue strength, align perfectly with the demanding requirements of dental implants, guaranteeing the restoration's functionality and durability. This narrative review aims to provide a comprehensive understanding of the manufacturing techniques employed for titanium and its alloy dental implants while shedding light on their intrinsic properties. It also presents crucial proof-of-concept examples, offering tangible evidence of these materials' effectiveness in clinical applications. However, despite their numerous advantages, certain limitations still exist necessitating ongoing research and development efforts. This review will briefly touch upon these restrictions and explore the evolving trends likely to shape the future of titanium and its alloy dental implants.

2.
Aging (Albany NY) ; 15(21): 12251-12263, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37934581

RESUMO

Drug resistance to chemotherapy agents presents a major obstacle to the effective treatment of hepatocellular carcinoma (HCC), a common type of liver cancer. Increasing evidence indicates a link between drug resistance and the recurrence of HCC. Polyphyllin I (PPI), a promising pharmaceutical candidate, has shown potential therapeutic advantages in the treatment of sorafenib-resistant hepatocellular carcinoma (SR-HCC cells). In this study, we sought to investigate the mechanism underlying the inhibitory effect of PPI on the invasion and metastasis of SR-HCC cells. Our in vitro studies included scratch wound-healing migration assays and transwell assays to examine PPI's effect on HCC cell migration and invasion. Flow cytometry was employed to analyze the accumulation or efflux of chemotherapy drugs. The results of these experiments demonstrated that PPI increased the susceptibility of HCC to sorafenib while inhibiting SR-HCC cell growth, migration, and invasion. Molecular docking analysis revealed that PPI exhibited a higher binding affinity with GRP78. Western blot analysis and immunofluorescence experiments showed that PPI reduced the expression of GRP78, E-cadherin, N-cadherin, Vimentin, and ABCG2 in SR-HCC cells. Interference with and overproduction of GRP78 in vitro impacted the proliferation, migration, invasion, and metastasis of HCC cells. Further examination revealed that PPI hindered the expression of GRP78 protein, resulting in a suppressive effect on SR-HCC cell migration and invasion. Histological examination of tumor tissue substantiated that administering PPI via gavage to HepG2/S xenograft nude mice inhibited tumor growth and significantly reduced tumor size, as evidenced by xenograft experiments involving nude mice. Hematoxylin and eosin (HE) staining of tumor tissue specimens, along with immunohistochemistry (IHC), were conducted to evaluate the expression levels of Ki67, GRP78, N-cadherin, Vimentin, and ABCG2. The results indicated that PPI administration decreased the levels of proteins associated with metastasis and markers of drug resistance in tumor tissues, impeding tumor growth and spread. Overall, our findings demonstrated that PPI effectively suppressed the viability, proliferation, invasion, and metastasis of SR-HCC cells both in vitro and in vivo by modulating GRP78 activity. These findings provide new insights into the mechanism of PPI inhibition of SR-HCC cell invasion and metastasis, highlighting PPI as a potential treatment option for sorafenib-resistant HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Sorafenibe/farmacologia , Sorafenibe/uso terapêutico , Chaperona BiP do Retículo Endoplasmático , Vimentina/metabolismo , Camundongos Nus , Preparações Farmacêuticas , Simulação de Acoplamento Molecular , Linhagem Celular Tumoral , Proliferação de Células , Caderinas/metabolismo , Movimento Celular
3.
Sci Total Environ ; 887: 164135, 2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37182780

RESUMO

BACKGROUND: Previous epidemiological findings on extreme temperature and preterm birth (PTB) were heterogeneous, especially for extreme cold exposure. Measured and unmeasured individual-level factors such as genetic factors or lifecourse exposures may constitute important contributors but have not been addressed. OBJECTIVES: We aimed to examine the association of gestational heat and cold exposure with PTB using a novel sibling-matched study. METHODS: Based on a multi-center population-based birth cohort across 16 counties in China, we included 10,826 sibling pairs born from March 2013 to December 2018. Conditional logistic and Cox Proportional Hazard regression models were used to estimate the effects of heat and cold exposure on PTB in each trimester, one and four weeks before delivery and the entire pregnancy. We also tested the heterogeneity in the association of temperature with PTB between siblings. FINDINGS: Exposure to heat during the third trimester and the entire pregnancy increased the risk of PTB. For heat (> 90th) defined with mean temperature, the odds ratios were 2.32 (1.63, 3.30) and 3.19 (2.22, 4.58), respectively. Cold exposure (< 10th) during the first, the third, and the entire pregnancy was associated with a higher PTB risk, with ORs (95%CIs) of 2.04 (1.43, 2.90), 3.13 (2.14, 4.58), and 4.26 (2.94, 6.19), respectively. We found slightly stronger associations of heat exposure during the entire pregnancy with the firstborn PTB, and stronger associations of cold exposure during one week and four weeks before delivery with secondborn PTB. CONCLUSIONS: Using a sibling-matched study, we took into account some mother-level unobserved confounding. Our research strengthens the evidence that gestational exposure to heat and cold increases the risk of PTB. Our findings may have important implications for improving the health of newborns in the context of climate change.


Assuntos
Nascimento Prematuro , Gravidez , Feminino , Humanos , Recém-Nascido , Irmãos , Temperatura , Estudos Prospectivos , China , Exposição Materna
4.
Int J Mol Sci ; 24(7)2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37047630

RESUMO

Transcriptome sequencing showed that syndecan-3 (SDC3) was differentially expressed in high-fat and low-fat mammary epithelial cells of Chinese Holstein cows. Previous studies found that SDC3 plays an important role in inflammatory diseases and virus infection. However, those studies did not confirm whether or not the functional gene SDC3, which plays an important role in regulating milk fat metabolism, has an effect on susceptibility to breast tissue diseases. Therefore, we studied the effects of SDC3 on milk lipid metabolism and inflammation in bovine mammary epithelial cells (BMECs) and further explored the common regulatory pathway of SDC3 in both. The overexpression of SDC3 increased the contents of triglycerides and cholesterol, reduced the content of non-esterified fatty acids, inhibited the expression of inflammatory factors (IL-6, IL-1ß, TNF-α and COX-2), and reduced the production of ROS in BMECs. However, silenced SDC3 had the opposite effect. Further exploring the mechanisms of SDC3, we found that SDC3 upregulated the expression of peroxisome proliferator-activated receptor gamma (PPARG) through the AMPK/SIRT1 signal pathway to promote milk fat synthesis. It also regulated the activation of the NF-κB pathway through the AMPK/SIRT1 signal pathway, reducing the expression of inflammatory factors and ROS production, thus inhibiting the inflammatory response of BMECs. Nuclear factor kappa B subunit 1 (NF-κB p50) was an important target of SDC3 in this process. To sum up, our results showed that SDC3 coregulated milk fat metabolism and inflammation through the AMPK/SIRT1 signaling pathway. This study laid a foundation for the comprehensive evaluation of breeding value based on multi-effect functional genes in dairy cow molecular breeding.


Assuntos
Leite , NF-kappa B , Feminino , Bovinos , Animais , Leite/metabolismo , NF-kappa B/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismo , Sindecana-3/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Glândulas Mamárias Animais/metabolismo , Transdução de Sinais , Metabolismo dos Lipídeos , Inflamação/metabolismo , Células Epiteliais/metabolismo
5.
Animals (Basel) ; 12(13)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35804595

RESUMO

Chitosan oligosaccharide (COS) is a variety of oligosaccharides, and it is also the only abundant basic amino oligosaccharide in natural polysaccharides. Chitosan oligosaccharide is a low molecular weight product of chitosan after enzymatic degradation. It has many biological effects, such as lipid-lowering, antioxidant and immune regulation. Previous studies have shown that chitosan oligosaccharide has a certain effect on fat synthesis, but the effect of chitosan oligosaccharide on milk fat synthesis of bovine mammary epithelial cells (BMECs) has not been studied. Therefore, this study aimed to investigate chitosan oligosaccharide's effect on milk fat synthesis in bovine mammary epithelial cells and explore the underlying mechanism. We treated bovine mammary epithelial cells with different concentrations of chitosan oligosaccharide (0, 100, 150, 200, 400 and 800 µg/mL) for 24 h, 36 h and 48 h respectively. To assess the effect of chitosan oligosaccharide on bovine mammary epithelial cells and determine the concentration and time for chitosan oligosaccharide treatment on cells, several in vitro cellular experiments, including on cell viability, cycle and proliferation were carried out. The results highlighted that chitosan oligosaccharide (100, 150 µg/mL) significantly promoted cell viability, cycle and proliferation, increased intracellular cholesterol content, and reduced intracellular triglyceride and non-esterified fatty acids content. Under the stimulation of chitosan oligosaccharide, the expression of genes downstream of Phosphorylated AMP-activated protein kinase (P-AMPK) and AMP-activated protein kinase (AMPK) signaling pathway changed, increasing the expression of peroxisome proliferator-activated receptor alpha (PPARα) and hormone-sensitive lipase (HSL), but the expression of sterol regulatory element-binding protein 1c (SREBP1) and its downstream target gene stearoyl-CoA desaturase (SCD1) decreased. In conclusion, these results suggest that chitosan oligosaccharide may inhibit milk fat synthesis in bovine mammary epithelial cells by activating the AMP-activated protein kinase signaling pathway, promoting the oxidative decomposition of fatty acids and inhibiting fatty acid synthesis.

6.
PLoS One ; 17(7): e0271578, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35849583

RESUMO

AIMS: Smooth muscle 22-alpha (SM22α) is an actin-binding protein that plays critical roles in mediating polymerization of actin filaments and stretch sensitivity of cytoskeleton in vascular smooth muscle cells (VSMCs). Multiple lines of evidence indicate the existence of SM22α in cardiomyocytes. Here, we investigated the effect of cardiac SM22α on the membrane architecture and functions of cardiomyocytes to pressure overload. METHODS: SM22α knock-out (KO) mice were utilized to assess the role of SM22α in the heart. Echocardiography was used to evaluate cardiac function, transverse aortic constriction (TAC) was used to induce heart failure, cell shortening properties were measured by IonOptix devices in intact cardiomyocytes, Ca2+ sensitivity of myofilaments was measured in permeabilized cardiomyocytes. Confocal microscopy, electron microscopy, western blotting, co-immunoprecipitation (co-IP), Real-Time Quantitative Reverse Transcription PCR (qRT-PCR) techniques were used to perform functional and structural analysis. RESULTS: SM22α ablation did not alter cardiac function at baseline, but mRNA levels of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and ß-myosin heavy chain (ß-MHC) were increased significantly compared with wild type (WT) controls. The membrane architecture was severely disrupted in SM22α KO cardiomyocytes, with disassembly and flattening of caveolae and disrupted T-tubules. Furthermore, SM22α was co-immunoprecipitated with caveolin-3 (Cav3), and the interaction between Cav3 and actin was significantly reduced in SM22α KO cells. SM22α KO cardiomyocytes displayed asynchronized SR Ca2+ release, significantly increased Ca2+ spark frequency. Additionally, the kinetics of sarcomere shortening was abnormal, accompanied with increased sensitivity and reduced maximum response of myofilaments to Ca2+ in SM22α KO cardiomyocytes. SM22α KO mice were more prone to heart failure after TAC. CONCLUSIONS: Our findings identified that SM22α may be required for the architecture and function of caveolae and T-tubules in cardiomyocytes.


Assuntos
Insuficiência Cardíaca , Proteínas dos Microfilamentos/metabolismo , Proteínas Musculares/metabolismo , Miócitos Cardíacos , Animais , Cálcio/metabolismo , Cavéolas/metabolismo , Caveolina 3/metabolismo , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Camundongos , Camundongos Knockout , Músculo Liso/metabolismo , Miócitos Cardíacos/metabolismo
8.
Membranes (Basel) ; 11(9)2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34564464

RESUMO

The use of an Amphotericin B_Ergosterol (AmBEr) channel as an artificial water channel in forward osmosis filtration (FO) was studied via molecular dynamics (MD) simulation. Three channel models were constructed: a common AmBEr channel and two modified C3deOAmB_Ergosterol (C3deOAmBEr) channels with different diameters (12 Å and 18 Å). During FO filtration simulation, the osmotic pressure of salt-water was a driving force for water permeation. We examined the effect of the modified C3deOAmBEr channel on the water transport performance. By tracing the change of the number of water molecules along with simulation time in the saltwater region, the water permeability of the channel models could be calculated. A higher water permeability was observed for a modified C3deOAmBEr channel, and there was no ion permeation during the entire simulation period. The hydrated ions and water molecules were placed into the channel to explore the ion leakage behavior of the channels. The mean squared displacement (MSD) of ions and water molecules was obtained to study the ion leakage performance. The Amphotericin B-based channels showed excellent selectivity of water molecules against ions. The results obtained on an atomistic scale could assist in determining the properties and the optimal filtration applications for Amphotericin B-based channels.

9.
Cancer Lett ; 474: 36-52, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31931030

RESUMO

Tumor-associated macrophages (TAMs) are important immunocytes associated with cancer metastasis. However, whether TAMs play a dominant role in mediating CXCL12/CXCR4-induced liver metastasis of colorectal cancer (CRC) remains unexplored. Herein, we found that CD206+ TAMs, which infiltrated at the invasive front, were correlated with CXCR4 expression and liver metastasis of CRC in clinical specimens. Several miRNAs (miR-25-3p, miR-130b-3p, miR-425-5p), upregulated in CRC cells by activation of the CXCL12/CXCR4 axis, could be transferred to macrophages via exosomes. These exosomal miRNAs induced M2 polarization of macrophages by regulating PTEN through activation of PI3K/Akt signaling pathway. In turn, M2 polarized macrophages promoted cancer metastasis by enhancing epithelial-mesenchymal transition (EMT) and secreting vascular endothelial growth factor (VEGF). Co-culture of CRC cells with macrophages transfected with these miRNAs or treated with exosomes enhanced their metastatic capacity both in vitro and in vivo. Clinically, the serum levels of exosomal miR-25-3p, miR-130b-3p and miR-425-5p were correlated with progression and metastasis of CRC. In conclusion, these results reveal a crucial role of exosomal miRNAs in mediating the crosstalk between CXCR4 overexpressing cancer cells and TAMs, providing potential therapeutic targets for circumventing liver metastasis of CRC.


Assuntos
Quimiocina CXCL12/metabolismo , Neoplasias Colorretais/patologia , Exossomos/genética , Neoplasias Hepáticas/secundário , Macrófagos/imunologia , MicroRNAs/genética , Receptores CXCR4/metabolismo , Idoso , Animais , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Movimento Celular , Proliferação de Células , Quimiocina CXCL12/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/metabolismo , Transição Epitelial-Mesenquimal , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Camundongos Nus , Invasividade Neoplásica , Prognóstico , Receptores CXCR4/genética , Transdução de Sinais , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
10.
ACS Appl Mater Interfaces ; 11(20): 18782-18796, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31059228

RESUMO

Mixed-matrix membranes (MMMs) have been drawing increasing attention due to the high permeability and high rejection capabilities for highly efficient wastewater treatment applications. Nonetheless, improving the water permeance while maintaining the high rejection capability is still an ongoing challenge for the practically state-of-the-art MMMs. Herein, a new class of poly(ether sulfone) (PES) based MMM containing metal-organic framework (MOF) nanofillers of HKUST-1 and blending with poly(methyl methacrylate- co-methacrylic acid) (PMMA- co-MAA) copolymer, designated as HKUST-1@mPES MMM, were developed for the highly efficient ultrafiltration (UF) process. In this study, the nanosized HKUST-1 nanofillers were removed by water dissolution as sacrificial templating materials, so that the additional nanovoids were deliberately generated throughout the dense polymer matrix. The introduction of PMMA- co-MAA copolymer facilitated the even dispersion of HKUST-1 nanofillers in a polymer matrix, by constructing the bridge connection between inorganic nanofillers and organic matrix. The resultant HKUST-1@mPES MMM exhibited a high pure water permeability (PWP) up to 490 L·m-2·h-1·bar-1, substantially reaching nearly 3 times higher than that of the mPES membrane without HKUST-1 nanofillers loading and maintaining a relatively high BSA rejection rate of 96% without obvious deterioration. The newly developed HKUST-1@mPES MMM thereby exhibited a comparable separation efficiency compared to the cutting-edge UF membranes reported so far. Overall, the nanovoid-generated approach provides new insight into developing advanced MMMs used for highly efficient water treatment applications.

11.
ACS Appl Mater Interfaces ; 11(21): 19462-19471, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31071260

RESUMO

Pressure retarded osmosis (PRO) process is hindered by severe fouling occurring within the porous support of the forward osmosis (FO) membranes. We designed a novel double-skinned FO membrane containing a polyamide salt-rejecting layer and a zwitterionic brush-decorated, multiwalled carbon nanotube (MWCNT/PSBMA) foulant-resisting layer on the back side. Our results demonstrated that the coating of the MWCNT/PSBMA layer on the porous polyketone (PK) support imparted enhanced hydrophilicity and smaller membrane pore size, thereby providing excellent resistance toward both protein adhesion and bacterial adsorption. We also further evaluated this resultant double-skinned membrane (i.e., TFC-MWCNT/PSBMA) in dynamic PRO fouling experiments using protein and alginate as model organic foulants. Compared to the pristine TFC-PK and hydrophobic TFC-MWCNT membranes, the TFC-MWCNT/PSBMA membrane exhibited not only the lowest water flux decline but also the highest water flux recovery after simple physical flushing. These results shed light on fabrication of antifouling PRO membranes for water purification purposes.

12.
Membranes (Basel) ; 8(4)2018 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-30563257

RESUMO

Polyamide (PA) membranes possess properties that allow for selective water permeation and salt rejection, and these are widely used for reverse osmotic (RO) desalination of sea water to produce drinking water. In order to design high-performance RO membranes with high levels of water permeability and salt rejection, an understanding of microscopic PA membrane structures is indispensable, and this includes water transport and ion rejection mechanisms on a molecular scale. In this study, two types of virtual PA membranes with different structures and densities were constructed on a computer, and water molecular transport properties through PA membranes were examined on a molecular level via direct reverse/forward osmosis (RO/FO) filtration molecular dynamics (MD) simulations. A quasi-non-equilibrium MD simulation technique that uses applied (RO mode) or osmotic (FO mode) pressure differences of several MPa was conducted to estimate water permeability through PA membranes. A simple NVT (Number, Volume, and Temperature constant ensemble)-RO MD simulation method was presented and verified. The simulations of RO and FO water permeability for a dense PA membrane model without a support layer agreed with the experimental value in the RO mode. This PA membrane completely rejected Na⁺ and Cl- ions during a simulation time of several nano-seconds. The naturally dense PA structure showed excellent ion rejection. The effect that the void size of PA structure exerted on water permeability was also examined.

13.
ACS Appl Mater Interfaces ; 10(51): 44880-44889, 2018 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-30484634

RESUMO

The cost-effective treatment of emulsified oily wastewater discharged by many industries and human societies is a great challenge. Herein, based on an aliphatic polyketone (PK) polymer with a good membrane formation ability and an intrinsic intermediate hydrophilicity, a new class of reduced PK (rPK) membranes combining an all hydrophilic and electrically neutral surface chemistry comprising ketone and hydroxyl groups, and a fibril-like morphology featuring re-entrant structure, was facilely prepared by phase separation and following fast surface reduction. The synergetic cooperation of surface chemistry and surface geometry endowed the prepared membranes with excellent superhydrophilicity, underwater superoleophobicity, and underoil superhydrophilicity, in addition to antiprotein-adhesion property. Thus, fouling-resistant and self-cleaning filtrations of challenging oil-in-water emulsions containing adhesive oil, surfactant, high salinity, and proteins were effortlessly realized with high flux (up to ∼50 000 L m-2 h-1 bar-1), slow and reversible flux decline, and low oil permeate (<20 ppm). In contrast, a commercial superhydrophilic microporous membrane made of mixed cellulose ester suffered severe fouling gradually or immediately when carrying out the emulsion filtrations due to its less than ideal surface properties. It is believed that this class of membranes with desirable superwettability, high flux, and preparation simplicity can be a potential new benchmark for high performance and large-scale oil-water separation in complex environments.

14.
Int Immunopharmacol ; 22(2): 451-64, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25073120

RESUMO

PURPOSE: A new strategy of adoptive and passive immunotherapy involves combining dendritic cells (DCs) with a subset of natural killer T lymphocytes termed cytokine-induced killer (CIK) cells. The objective of this systematic review and meta-analysis was to evaluate the safety and efficacy of DC-CIK therapy vs. placebo, no intervention, conventional treatments, or other complementary and alternative medicines for malignant tumors. METHOD: We searched PubMed, Medline, Embase, Cochrane, Wangfang, Weipu, CNKI databases and reference lists of articles. We selected randomized controlled trials of DC-CIK therapy vs. placebo, no intervention, conventional treatments, or other complementary and alternative medicines in patients with all types and stages of malignant tumor. Primary outcome measures were overall survival and treatment response. Secondary outcome measures were health-related quality of life (HRQoL) assessment, progression free survival (PFS), and adverse events. RESULTS: Six trials met our inclusion criteria. There was evidence that chemotherapy+DC-CIK increased the 2-year (RR 2.88, 95% CI 1.38 to 5.99, P=0.005) and 3-year (RR 11.67, 95% CI 2.28 to 59.69, P=0.003) survival rates and progression free survival (RR 0.64, 95% CI 0.34 to 0.94, P<0.0001) in patients with non-small cell lung cancer compared to those treated with chemotherapy alone. DC-CIK therapy appears to be well-tolerated by cancer patients and to improve post-treatment patient health related quality of life. CONCLUSION: DC-CIK immunotherapy is a safe and effective treatment for patients with malignant tumors. Further clinical trials to provide supportive evidence for the routine use of DC-CIK therapy in clinical practice are warranted.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Células Matadoras Induzidas por Citocinas , Células Dendríticas , Imunoterapia , Neoplasias/terapia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
Biochem Pharmacol ; 89(4): 503-14, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24704474

RESUMO

Chrysin (5,7-di-OH-flavone), a widely distributed natural flavonoid, has been well documented for involving in various biological activities, especially in regulation of peroxisome proliferator activated receptor γ (PPARγ) activity as a modest modulator. However, the exact molecular mechanism is still unrevealed. In the current study, for the first time, we discovered that, chrysin not only significantly attenuated inflammation in high-fat feeding mice, but also alleviated high fat diet-induced hepatic, muscular steatosis in obese mice without altering the body weight. Chrysin decreases the infiltration of macrophages into adipose tissue in obese mice. In addition, chrysin was also found to induce an anti-inflammatory M2 phenotype and decreases M1 phenotype, both in peritoneal macrophages of obese mice and cultured macrophages in vitro, and thereby, chrysin changed the M1/M2 status. Our data further showed that chrysin regulated the phenotype of macrophages through enhancing the transcriptional activation of PPARγ and the expression of its target genes. Taken together, we conclude that chrysin may serve as an effective modulator of PPARγ during the pathogenesis of inflammation, thereby our findings shed light on the potential therapeutic feature of chrysin in recovering inflammatory diseases via regulating M1/M2 status.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Divisão Celular/efeitos dos fármacos , Fígado Gorduroso/tratamento farmacológico , Flavonoides/uso terapêutico , Macrófagos Peritoneais/efeitos dos fármacos , Miosite/tratamento farmacológico , PPAR gama/agonistas , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/imunologia , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/farmacologia , Linhagem Celular Transformada , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Fígado Gorduroso/imunologia , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Flavonoides/administração & dosagem , Flavonoides/efeitos adversos , Flavonoides/farmacologia , Humanos , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/metabolismo , Fígado/patologia , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/imunologia , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Miosite/imunologia , Miosite/metabolismo , Miosite/patologia , Hepatopatia Gordurosa não Alcoólica , Obesidade/fisiopatologia , PPAR gama/genética , PPAR gama/metabolismo , Distribuição Aleatória , Organismos Livres de Patógenos Específicos , Transcrição Gênica/efeitos dos fármacos
16.
Biotechnol Lett ; 36(7): 1431-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24652544

RESUMO

Both bursin (Lys-His-Gly-NH2) and Gagnon's peptides (Lys-Asn-Pro-Tyr) can induce B-cell differentiation. However, it is unclear whether a recombinant hybrid polypeptide consisting of a tandem array of 14 copies of bursin and two copies of Gagnon's peptide can induce the proliferative activity of lymphocytes. Here, this recombinant hybrid polypeptide was expressed in Escherichia coli and purified by SDS-PAGE. Various assays showed that it not only promoted B-lymphocyte proliferation in vitro but also increased the titers of antibodies directed against infectious bursal disease virus fourfold in the sera of chickens vaccinated with the inactivated infectious bursal disease virus vaccine. The recombinant hybrid polypeptide also reduced the pathological lesions in the bursa of Fabricius caused by infectious bursal disease virus BC6/85. Our results show that this recombinant hybrid polypeptide may be a promising immune adjuvant.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Infecções por Birnaviridae/veterinária , Vírus da Doença Infecciosa da Bursa/imunologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas Virais/imunologia , Adjuvantes Imunológicos/genética , Animais , Anticorpos Antivirais/sangue , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Infecções por Birnaviridae/imunologia , Infecções por Birnaviridae/patologia , Infecções por Birnaviridae/prevenção & controle , Proliferação de Células , Galinhas , Escherichia coli/genética , Expressão Gênica , Vírus da Doença Infecciosa da Bursa/genética , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/patologia , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/genética , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
17.
Exp Cell Res ; 322(1): 30-8, 2014 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-24440556

RESUMO

Post-translational regulation plays a critical role in the control of cell growth and proliferation. The phosphorylation of peroxisome proliferator-activated receptor γ (PPARγ) is the most important post-translational modification. The function of PPARγ phosphorylation has been studied extensively in the past. However, the relationship between phosphorylated PPARγ1 and tumors remains unclear. Here we investigated the role of PPARγ1 phosphorylation in human fibrosarcoma HT1080 cell line. Using the nonphosphorylation (Ser84 to alanine, S84A) and phosphorylation (Ser84 to aspartic acid, S84D) mutant of PPARγ1, the results suggested that phosphorylation attenuated PPARγ1 transcriptional activity. Meanwhile, we demonstrated that phosphorylated PPARγ1 promoted HT1080 cell proliferation and this effect was dependent on the regulation of cell cycle arrest. The mRNA levels of cyclin-dependent kinase inhibitor (CKI) p21(Waf1/Cip1) and p27(Kip1) descended in PPARγ1(S84D) stable HT1080 cell, whereas the expression of p18(INK4C) was not changed. Moreover, compared to the PPARγ1(S84A), PPARγ1(S84D) up-regulated the expression levels of cyclin D1 and cyclin A. Finally, PPARγ1 phosphorylation reduced sensitivity to agonist rosiglitazone and increased resistance to anticancer drug 5-fluorouracil (5-FU) in HT1080 cell. Our findings establish PPARγ1 phosphorylation as a critical event in human fibrosarcoma growth. These findings raise the possibility that chemical compounds that prevent the phosphorylation of PPARγ1 could act as anticancer drugs.


Assuntos
Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Fibrossarcoma/patologia , PPAR gama/metabolismo , Proteínas Quinases/metabolismo , Processamento de Proteína Pós-Traducional , Linhagem Celular Tumoral , Fibrossarcoma/tratamento farmacológico , Fibrossarcoma/genética , Fibrossarcoma/metabolismo , Regulação Neoplásica da Expressão Gênica , Genes cdc , Células HEK293 , Humanos , PPAR gama/genética , Fosforilação , Ativação Transcricional
18.
J Cell Biochem ; 114(9): 1969-77, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23494891

RESUMO

Diabetes is the most common chronic disease in the world and causes complications with many diseases, such as heart disease and osteoporosis. Osteoporosis is a systemic bone disease characterized by imbalance in bone resorption and bone formation. Osteoclast is type of bone cell that functions in bone resorption and plays a critical role in bone remodeling. Rosiglitazone and pioglitazone, which belong to Thiazolidinediones(TZDs), are commonly used antidiabetic drugs. As PPARγ full agonists, they can activate PPARγ in a ligand-dependent way. Recent studies indicate that these PPARγ full agonists have some side effects, such as weight gain and bone loss, which may increase the risk of osteoporosis. In contrast, selective PPARγ Modulators (SPPARγMs) are novel PPARγ ligands that can activate PPARγ in different ways and lead to distinct downstream genes. Mice bone marrow cells were stimulated with recombinant mouse RANKL and M-CSF to generate osteoclasts. To determine the effect on osteoclasts formation, PPARγ ligands (Rosiglitazone, Fmoc-L-Leu, and Telmisartan) were added at the beginning of the culture. Rosiglitazone significantly increased the differentiation of multinucleated osteoclasts, while osteoclasts formation triggered by SPPARγMs was much less than that displayed by rosiglitazone. We found that the enhancement of PPARγ ligands may be associated with TRAF6 and downstream ERK signal pathway. We also demonstrated osteoclasts show characteristic M2 phenotype and can be further promoted by PPARγ ligands, especially rosiglitazone. In conclusion, reduced osteoclasts differentiation characteristic of SPPARγMs highlights SPPARγMs potential as therapeutic targets in diabetes, versus traditional antidiabetic drugs.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , PPAR gama/metabolismo , Animais , Western Blotting , Ensaio de Imunoadsorção Enzimática , Camundongos , Camundongos Endogâmicos BALB C , Osteoclastos/metabolismo , PPAR gama/agonistas , Reação em Cadeia da Polimerase em Tempo Real , Rosiglitazona , Transdução de Sinais/efeitos dos fármacos , Tiazolidinedionas/farmacologia
19.
Antioxid Redox Signal ; 19(12): 1337-55, 2013 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-23373752

RESUMO

AIMS: Malignant melanoma is well known for abundant reactive oxygen species (ROS) that exist in the primary tumor environment. Within this microenvironment, tumor-associated macrophages (TAMs) play substantial roles in multiple steps of tumor development in terms of tumor growth, invasion, and metastasis. We therefore aimed to determine whether this high-level ROS in primary melanoma is capable to promote tumor invasiveness by influencing TAM properties. Moreover, we wanted to further investigate probable underlying mechanisms. RESULTS: We characterized malignant melanoma TAMs as a heterogeneous phenotype, which possesses both M1 and M2 markers. We also revealed a role for high-level intracellular ROS in enhancing proinvasion signature of TAMs by strongly increasing their tumor necrosis factor α secretion, which is possibly attributed to ROS-enhanced peroxisome proliferator-activated receptor γ (PPARγ) translocation mediated by MAPK/ERK kinase 1. INNOVATION: This is the first study demonstrating that high levels of ROS in the primary melanoma environment can influence TAM behaviors. Furthermore, we are also the first to indentify that nucleus-to-cytoplasm translocation of PPARγ is significantly upregulated by ROS and responsible for the proinvasiveness capacity of melanoma TAMs. CONCLUSION: Taken together, our data describe how a high level of ROS plays a critical role in enhancing the proinvasion characteristic of TAMs in malignant melanoma.


Assuntos
Macrófagos/metabolismo , Melanoma Experimental/metabolismo , Estresse Oxidativo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Núcleo Celular/metabolismo , MAP Quinase Quinase 1/metabolismo , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Camundongos , Invasividade Neoplásica , Transplante de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , PPAR gama/metabolismo , Transporte Proteico , Espécies Reativas de Oxigênio/metabolismo , Transcriptoma
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