RESUMO
The efficacy of chimeric antigen receptor (CAR) T cell immunotherapy is limited by insufficient infiltration and activation of T cells due to the immunosuppressive tumor microenvironment. Preclinical studies with optimized mouse CAR T cells in immunocompetent mouse cancer models will help define the mechanisms underlying immunotherapy resistance. Here, we present a protocol for preparing mouse T cells and generating CAR T cells. We then detail procedures for testing their therapeutic efficacy and tracking them in a syngeneic mouse glioma model. For complete details on the use and execution of this protocol, please refer to Zhang et al.1.
Assuntos
Glioma , Receptores de Antígenos Quiméricos , Animais , Camundongos , Imunoterapia Adotiva/métodos , Receptores de Antígenos Quiméricos/genética , Imunoterapia , Linfócitos T , Glioma/terapia , Modelos Animais de Doenças , Microambiente TumoralRESUMO
The viable but nonculturable (VBNC) state is adopted by many foodborne pathogenic bacteria to survive in adverse conditions. This study found that lactic acid, a widely used food preservative, can induce Yersinia enterocolitica to enter a VBNC state. Y. enterocolitica treated with 2 mg/mL lactic acid completely lost culturability within 20 min, and 10.137 ± 1.693 % of the cells entered a VBNC state. VBNC state cells could be recovered (resuscitated) in tryptic soy broth (TSB), 5 % (v/v) Tween80-TSB, and 2 mg/mL sodium pyruvate-TSB. In the VBNC state of Y. enterocolitica induced by lactic acid, the intracellular adenosine triphosphate (ATP) concentration and various enzyme activities were decreased, and the reactive oxygen species (ROS) level was elevated, compared with uninduced cells. The VBNC state cells were significantly more resistant to heat and simulated gastric fluid than uninduced cells, but their ability to survive in a high-osmotic-pressure environment was significantly less than that of uninduced cells. The VBNC state cells induced by lactic acid changed from long rod-like to short rod-like, with small vacuoles at the cell edges; the genetic material was loosened and the density of cytoplasm was increased. The VBNC state cells had decreased ability to adhere to and invade Caco-2 (human colorectal adenocarcinoma) cells. The transcription levels of genes related to adhesion, invasion, motility, and resistance to adverse environmental stress were downregulated in VBNC state cells relative to uninduced cells. In meat-based broth, all nine tested strains of Y. enterocolitica entered the VBNC state after lactic acid treatment; among these strains, only VBNC state cells of Y. enterocolitica CMCC 52207 and Isolate 36 could not be recovered. Therefore, this study is a wake-up call for food safety problems caused by VBNC state pathogens induced by lactic acid.
Assuntos
Adenocarcinoma , Yersinia enterocolitica , Humanos , Células CACO-2 , Cafeína , Ácido LácticoRESUMO
The presence of Salmonella in nature poses a significant and unacceptable threat to the human public health domain. In this study, the antibacterial effect and mechanism of ultrasound (US) combined with Litsea cubeba essential oil nanoemulsion (LEON) on Salmonella. LEON + US treatment has a significant bactericidal effect on Salmonella. Reactive oxygen species (ROS), malondialdehyde (MDA) detection, N-phenyl-l-naphthylamine (NPN) uptake and nucleic acid release assays showed that LEON + US exacerbated cell membrane lipid peroxidation and increased the permeability of the cell membrane. The results of field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) showed that LEON + US treatment was able to alter cell morphology. It can be observed by flow cytometry (FCM) that LEON + US treatment can cause cell apoptosis. In addition, bacterial counts of cherry tomatoes treated with LEON (0.08 µL/mL) + US (345 W/cm2) for 9 min were reduced by 6.50 ± 0.20 log CFU/mL. This study demonstrates that LEON + US treatment can be an effective way to improve the safety of fruits and vegetables in the food industry.
Assuntos
Litsea , Óleos Voláteis , Solanum lycopersicum , Humanos , Óleos Voláteis/farmacologia , Salmonella , Antibacterianos/farmacologiaRESUMO
Shigella sonnei, the causative agents of bacillary dysentery, remains a significant threat to public health. Litsea cubeba essential oil (LC-EO), one of the natural essential oils, exhibited promising biological activities. In this study, the antibacterial effects and possible mechanisms of LC-EO on S. sonnei and its application in lettuce medium were investigated. The minimum inhibitory concentration (MIC) of LC-EO against S. sonnei ATCC 25931 and CMCC 51592 was 4 and 6 µL/mL, respectively. The LC-EO could inhibit the growth of S. sonnei, and decreased S. sonnei to undetectable levels with 4 µL/mL for 1 h in Luria-Bertani broth. The antibacterial mechanism indicated that after the treatment of LC-EO, the production of reactive oxygen species and the activity of superoxide dismutase were significantly elevated in S. sonnei cells, and eventually led to the lipid oxidation product, the malondialdehyde content that significantly increased. Moreover, LC-EO at 2 MIC could destroy 96.51% of bacterial cell membrane integrity, and made S. sonnei cells to appear wrinkled with a rough surface, so that the intracellular adenosine triphosphate leakage was about 0.352-0.030 µmol/L. Finally, the results of application evaluation indicated that the addition of LC-EO at 4 µL/mL in lettuce leaves and 6 µL/mL in lettuce juice could decrease the number of S. sonnei to undetectable levels without remarkable influence on the lettuce leaf sensory quality. In summary, LC-EO exerted strong antibacterial activity and has the potential to control S. sonnei in food industry.
Assuntos
Litsea , Óleos Voláteis , Óleos Voláteis/farmacologia , Lactuca , Shigella sonnei , Antibacterianos/farmacologia , Testes de Sensibilidade MicrobianaRESUMO
This study investigated the antibacterial and antibiofilm mechanism of ultrasound (US) combined with citral nanoemulsion (CLNE) against Staphylococcus aureus and mature biofilm. Combined treatments resulted in greater reductions in bacterial numbers compared to ultrasound or CLNE treatments alone. Confocal laser scanning microscopy (CLSM), flow cytometry (FCM), protein nucleic acid leakage, and N-phenyl-l-naphthylamine (NPN) uptake analysis showed that the combined treatment disrupted cell membrane integrity and permeability. Reactive oxygen species (ROS) and malondialdehyde (MDA) assays indicated that US+CLNE exacerbated cellular oxidative stress and membrane lipid peroxidation. Field emission scanning electron microscopy (FESEM) revealed that the synergistic processing of ultrasound and CLNE resulted in cell rupture and collapse. In addition, US+CLNE showed a more pronounced removal effect than both alone in the biofilm on the stainless steel sheet. US+CLNE reduced biomass, the number of viable cells in the biofilm, cell viability and EPS polysaccharide contents. The results of CLSM also showed that US+CLNE disrupted the structure of the biofilm. This research elucidates the synergistic antibacterial and anti-biofilm mechanism of ultrasound combined citral nanoemulsion, which provides a safe and efficient sterilization method for the food industry.
Assuntos
Antibacterianos , Staphylococcus aureus , Antibacterianos/química , Monoterpenos Acíclicos , Biofilmes , Testes de Sensibilidade MicrobianaRESUMO
Viable but nonculturable (VBNC) state bacteria are difficult to detect in the food industry due to their nonculturable nature and their recovery characteristics pose a potential threat to human health. The results of this study indicated that S. aureus was found to enter the VBNC state completely after induced by citral (1 and 2 mg/mL) for 2 h, and after induced by trans-cinnamaldehyde (0.5 and 1 mg/mL) for 1 h and 3 h, respectively. Except for VBNC state cells induced by 2 mg/mL citral, the VBNC state cells induced by the other three conditions (1 mg/mL citral, 0.5 and 1 mg/mL trans-cinnamaldehyde) were able to be resuscitated in TSB media. In the VBNC state cells induced by citral and trans-cinnamaldehyde, the ATP concentration was reduced, the hemolysin-producing ability was significantly decreased, but the intracellular ROS level was elevated. The results of heat and simulated gastric fluid experiments showed different environment resistance on VBNC state cells induced by citral and trans-cinnamaldehyde. In addition, by observing the VBNC state cells showed that irregular folds on the surface, increased electron density inside and vacuoles in the nuclear region. What's more, S. aureus was found to enter the VBNC state completely after induced by meat-based broth containing citral (1 and 2 mg/mL) for 7 h and 5 h, after induced by meat-based broth containing trans-cinnamaldehyde (0.5 and 1 mg/mL) for 8 h and 7 h. In summary, citral and trans-cinnamaldehyde can induce S. aureus into VBNC state and food industry needs to comprehensively evaluate the antibacterial capacity of these two plant-derived antimicrobial agents.
Assuntos
Anti-Infecciosos , Staphylococcus aureus , Humanos , Monoterpenos AcíclicosRESUMO
OBJECTIVE: MicroRNAs (miRNAs) have been shown to play an important role in myocardial ischemia/reperfusion (MI/R) injury. This study aimed to determine the role of miR-432 in MI/R injury. METHODS: We established a MI/R injury model by ligation/untying of the left anterior descending coronary artery, and used viral infection to regulate gene expression, such as that of miR-432 in vitro and in vivo, and used RT-qPCR to detect the expression of the gene at mRNA level. Finally, western blotting and immunochemistry analyses were used to determine the protein level. RESULTS: The results of this study show that miR-432 is upregulated in the heart following MI/R injury and that miR-432 overexpression showed a significant decrease, while miR-432 knockdown showed a significant increase in the ratio of the infarct area (IA) to the area at risk (AAR) and levels of serum creating phosphokinase (CPK). Moreover, miR-432 augmented the activation of the ß-catenin pathway and decreased the rate of apoptosis in the mice heart at 24 hours after MI/R injury by targeting RBM5. At the same time, miR-432 overexpression enhanced HIF-1α activation, while ß-catenin deletion attenuated HIF-1α activation induced by miR-432 overexpression. Importantly, ß-catenin and HIF-1α knockdown significantly increased the rate of apoptosis and the ratio of IA to AAR and levels of serum CPK induced by miR-432 overexpression at 24 hours after MI/R injury. miR-432 overexpression strongly decreased levels of SOD and GSH-PX activity, and increased levels of MDA activity and the expression of the gp91phox protein in the mice hearts at 24 hours after MI/R injury, while miR-432 knockdown exerted an opposite effect. miR-432 was also found to have increased NRF2 protein levels by targeting KEAP1 protein expression. NRF2 knockdown reversed the downregulation of the levels of gp91phox protein and MDA, while it also reversed the upregulation of the levels of SOD and GSH-PX induced by miR-432 overexpression in the heart of the mice at 24 hours after MI/R injury. CONCLUSION: miR-432 protects against MI/R injury by activating the ß-catenin/HIF-1α pathway and augmenting NRF2-mediated anti-oxidative stress.
RESUMO
Pseudomonas aeruginosa biofilm formation has been considered to be an important determinant of its pathogenicity in most infections. The antibiofilm activity of trans-cinnamaldehyde (TC) against P. aeruginosa was investigated in this study. Results demonstrated that the minimum inhibitory concentration (MIC) of TC against P. aeruginosa was 0.8 mg/mL, and subinhibitory concentrations (SICs) was 0.2 mg/mL and below. Crystal violet staining showed that TC at 0.05-0.2 mg/mL reduced biofilm biomass in 48 h in a concentration-dependent mode. The formation area of TC-treated biofilms was significantly declined (p < 0.01) on the glass slides observed by light microscopy. Field-emission scanning electron microscopy further demonstrated that TC destroyed the biofilm morphology and structure. Confocal laser scanning microscopic observed the dispersion of biofilms and the reduction of exopolysaccharides after TC treatment stained with concanavalin A (Con-A)-fluorescein isothiocyanate conjugate and Hoechst 33258. Meanwhile, TC caused a significant decrease (p < 0.01) in the component of polysaccharides, proteins, and DNA in extracellular polymeric substance. The swimming and swarming motility and quorum sensing of P. aeruginosa was also found to be significantly inhibited (p < 0.01) by TC at SICs. Furthermore, SICs of TC repressed the several genes transcription associated with biofilm formation as determined by real-time quantitative polymerase chain reaction. Overall, our findings suggest that TC could be applied as natural and safe antibiofilm agent to inhibit the biofilm formation of P. aeruginosa.
Assuntos
Antibacterianos , Pseudomonas aeruginosa , Antibacterianos/farmacologia , Matriz Extracelular de Substâncias Poliméricas , Biofilmes , Percepção de Quorum/genéticaRESUMO
In this study, a novel citral nanoemulsion (CLNE) was prepared by ultrasonic emulsification. The synergistic antibacterial mechanism of ultrasound combined with CLNE against Salmonella Typhimurium and the effect on the physicochemical properties of purple kale were investigated. The results showed that the combined treatment showed obviously inactivate effect of S. Typhimurium. Treatment with 0.3 mg/mL CLNE combined with US (20 kHz, 253 W/cm2) for 8 min reduced S. Typhimurium populations in phosphate-buffered saline (PBS) by 9.05 log CFU/mL. Confocal laser scanning microscopy (CLSM), flow cytometry (FCM), protein and nucleic acid release assays showed that the US combination CLNE disrupt the integrity of S. Typhimurium membranes. Reactive oxygen species (ROS) and malondialdehyde (MDA) detection indicated that US+CLNE exacerbated oxidative stress and lipid peroxidation in cell membranes. The morphological changes of cells after different treatments by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) illustrated that the synergistic effect of US+CLNE treatment changed the morphology and internal microstructure of the bacteriophage cells. Application of US+CLNE on purple kale leaves for 6 min significantly (P < 0.05) reduced the number of S. Typhimurium, but no changes in the physicochemical properties of the leaves were detected. This study elucidates the synergistic antibacterial mechanism of ultrasound combined with CLNE and provides a theoretical basis for its application in food sterilization.
Assuntos
Brassica , Salmonella typhimurium , Monoterpenos Acíclicos/farmacologia , Antibacterianos/farmacologiaRESUMO
Introduction: The biosynthesis of the secondary cell wall (SCW) is orchestrated by an intricate hierarchical transcriptional regulatory network. This network is initiated by first-layer master switches, SCW-NAC transcription factors, which in turn activate the second-layer master switches MYBs. These switches play a crucial role in regulating xylem specification and differentiation during SCW formation. However, the roles of most MYBs in woody plants are yet to be fully understood. Methods: In this study, we identified and isolated the R2R3-MYB transcription factor, PtoMYB031, from Populus tomentosa. We explored its expression, mainly in xylem tissues, and its role as a transcriptional repressor in the nucleus. We used overexpression and RNA interference techniques in poplar, along with Yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays, to analyze the regulatory effects of PtoMYB031. Results: Overexpression of PtoMYB031 in poplar significantly reduced lignin, cellulose, and hemicellulose content, and inhibited vascular development in stems, resulting in decreased SCW thickness in xylem tissues. Gene expression analysis showed that structural genes involved in SCW biosynthesis were downregulated in PtoMYB031-OE lines. Conversely, RNA interference of PtoMYB031 increased these compounds. Additionally, PtoMYB031 was found to recruit the repressor PtoZAT11, forming a transcriptional inhibition complex. Discussion: Our findings provide new insights into how PtoMYB031, through its interaction with PtoZAT11, forms a complex that can suppress the expression of key regulatory genes, PtoWND1A and PtoWND2B, in SCW biosynthesis. This study enhances our understanding of the transcriptional regulation involved in SCW formation in poplar, highlighting the significant role of PtoMYB031.
RESUMO
Litsea cubeba essential oil (LC-EO) has anti-insecticidal, antioxidant, and anticancer proper-ties; however, its antimicrobial activity toward Cronobacter sakazakii has not yet been researched extensively. The objective of this study was to investigate the antimicrobial and antibiofilm effects of LC-EO toward C. sakazakii, along with the underlying mechanisms. The minimum inhibitory concentrations of LC-EO toward eight different C. sakazakii strains ranged from 1.5 to 4.0 µL/mL, and LC-EO exposure showed a longer lag phase and lower specific growth compared to untreated bacteria. LC-EO increased reactive oxygen species production, decreased the integrity of the cell membrane, caused cell membrane depolarization, and decreased the ATP concentration in the cell, showing that LC-EO caused cellular damage associated with membrane permeability. LC-EO induced morphological changes in the cells. LC-EO inhibited C. sakazakii in reconstituted infant milk formula at 50 °C, and showed effective inactivation of C. sakazakii biofilms on stainless steel surfaces. Confocal laser scanning and attenuated total reflection-Fourier-transform infrared spectrometry indicated that the biofilms were disrupted by LC-EO. These findings suggest a potential for applying LC-EO in the prevention and control of C. sakazakii in the dairy industry as a natural antimicrobial and antibiofilm agent.
RESUMO
Shigella sonnei is a species of Shigella, and the infection rate of S. sonnei is increasing year by year. Eugenol is an active ingredient in clove essential oil and is a generally recognized as safe (GRAS)-certified food ingredient. The mechanism of inhibition of S. sonnei by eugenol has been investigated in this study. The minimum inhibitory concentration of eugenol against both S. sonnei ATCC 25931 and S. sonnei CMCC 51592 was 0.5 mg/mL and minimum bactericidal concentration (MBC) for both strains was 0.8 mg/mL. The inhibition effect of eugenol against S. sonnei was due to increased levels of reactive oxygen species in cells, changed cell membrane permeability, and induced cell membrane dysfunction, for instance, cell membrane hyperpolarization and intracellular ATP concentration drops. The results of confocal laser scanning microscope and field emission scanning electron microscopy showed that eugenol leads to decreased cell membrane integrity, resulting in changed cell morphology. Moreover, eugenol inactivated S. sonnei in Luria-Bertani (LB) broth and lettuce juice. These results indicated that eugenol could inactivate S. sonnei and has the potential to control S. sonnei in the food industry.
Assuntos
Disenteria Bacilar , Shigella sonnei , Eugenol/farmacologia , Lactuca/microbiologia , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologiaRESUMO
Shigella flexneri (Sh. flexneri), which can be found in food and the environment, is a widespread food-borne pathogen that causes human diarrhea termed "shigellosis". In this study, eugenol, a natural active substance, was investigated for its antibacterial activity against Sh. flexneri. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of eugenol against Sh. flexneri ATCC 12022 was 0.5 and 0.8 mg/mL. The growth curves and inhibitory effect in LB broth, PBS, vegetable juice, and minced pork showed that eugenol had a good activity against Sh. flexneri. Research findings indicated the superoxide dismutase activity of Sh. flexneri was inhibited after eugenol treatment, resulting in concentrations of intracellular reactive oxygen species and an increase in malondialdehyde. The flow cytometry analysis and field emission scanning electron microscopy results revealed obvious damage to cell membrane integrity and changes in the morphology of Sh. flexneri. In addition, the intracellular ATP concentration leaked from 0.5 µM to below 0.05 µM and the membrane potential showed a concentration-dependent depolarization after eugenol treatment. In summary, eugenol exerted strong antibacterial activity and has the potential to control Sh. flexneri in the food industry.
RESUMO
Cinnamaldehyde (CA) has demonstrated anti-inflammatory, anti-tumor and anti-cancer activities; Its antimicrobial and antibiofilm actions against Shigella flexneri, on the other hand, have not been investigated. Sh. flexneri is a gram-negative foodborne pathogen that can be widely found in nature and some industrial production environments. In this current research, our aim was to examine the influences of CA on planktonic bacteria and biofilm formation. The minimum inhibitory concentration (MIC) of CA against Sh. flexneri strain was 100 µg/mL, while bacteria treated with CA showed a longer lag phase compared with the untreated control. CA effectively inactivated the Sh. flexneri in LB broth and fresh lettuce juice. CA treatment resulted in cell membrane permeability changes and dysfunction, as proven by cell membrane depolarization, decreased intracellular ATP concentration. In addition, CA was also discovered to increase the level of reactive oxygen species (ROS) in cells, and induce morphological changes in cells. Crystal violet staining showed that the biomass of biofilm was decreased significantly with CA in 24 h. Light microscopy and field emission scanning electron microscopy (FESEM) observations demonstrated decreased biofilm adhesion and destruction of biofilm architecture after treatment with CA. These findings indicated that CA acts as a natural bacteriostatic agent to control Sh. flexneri in food processing and production.
Assuntos
Plâncton , Shigella flexneri , Acroleína/análogos & derivados , Trifosfato de Adenosina/metabolismo , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Bactérias , Biofilmes , Violeta Genciana , Testes de Sensibilidade Microbiana , Espécies Reativas de Oxigênio/metabolismoRESUMO
Inhibitory neurotransmitter gamma-aminobutyric acid (GABA) is an immunomodulator to inhibit immune-mediated pro-inflammatory response and has been used to treat various immune-related diseases in mammals. However, the immunoregulatory effect of GABA in crustaceans has not been reported. This study evaluates the regulatory effect of dietary GABA supplementation on the innate immune status and immunoregulatory potential in lipopolysaccharide (LPS)-induced immune response in juvenile Eriocheir sinensis. Juvenile crabs were fed with six diets supplemented with graded GABA levels (0, 40, 80, 160, 320 and 640 mg/kg dry matter) for 8 weeks and then 24 h LPS challenge test was carried out. The results showed that dietary GABA supplementation significantly decreased mortality at 4 and 8 weeks. Moreover, the hemocyanin content, acid phosphatase, and alkaline phosphatase activities significantly increased in the crabs fed GABA supplementation compared with the control. On the contrary, the alanine aminotransferase and alanine aminotransferase activities in serum decreased significantly in the GABA supplementation groups compared with the control. Similarly, superoxide dismutase activity, glutathione content, and the transcriptional expression of the antioxidant-related genes and immune-related genes were significantly higher in the GABA supplementation groups than in the control. In addition, the mRNA expressions of anti-lipopolysaccharide factors (ALF 1, ALF 2, ALF 3) and inflammatory signaling pathways related genes (TLR, Myd88, Relish, LITAF, P38-MAPK, ADAM17) were significantly up-regulated in LPS stimulation groups compared with PBS treatment. Meanwhile, pro-apoptosis-related genes' mRNA expressions were significantly up-regulated, and anti-apoptosis-related genes were significantly down-regulated under LPS stimulation compared with PBS treatment. However, GABA pretreatment effectively alleviated LPS-induced immune overresponse and apoptosis. Therefore, this study demonstrates that dietary GABA supplementation could be used as an immunomodulator to improve the non-specific immunity and antioxidant capacity and alleviate the immune-mediated immune overresponse of juvenile E. sinensis.
Assuntos
Braquiúros , Lipopolissacarídeos , Alanina Transaminase , Ração Animal/análise , Animais , Antioxidantes/metabolismo , Braquiúros/metabolismo , China , Dieta/veterinária , Imunidade Inata , Lipopolissacarídeos/farmacologia , Mamíferos/metabolismo , RNA Mensageiro , Ácido gama-Aminobutírico/farmacologiaRESUMO
Shigella sonnei (S. sonnei) infection accounted for approximately 75% of annual outbreaks of shigellosis, with the vast majority of outbreaks due to the consumption of contaminated foods (e.g., fresh vegetables, potato salad, fish, beef, etc.). Thus, we investigated the antibacterial effect and mechanism of linalool on S. sonnei and evaluated the effect of linalool on the sensory quality of lettuce. The minimum inhibitory concentration (MIC) of linalool against S. sonnei ATCC 25931 was 1.5 mg/mL. S. sonnei was treated with linalool at 1× MIC for 30 min and the amount of bacteria was decreased below the detection limit (1 CFU/mL) in phosphate-buffered saline (PBS) and Luria-Bertani (LB) medium. The bacterial content of the lettuce surface was reduced by 4.33 log CFU/cm2 after soaking with linalool at 2× MIC. Treatment with linalool led to increased intracellular reactive oxygen species (ROS) levels, decreased intracellular adenosine-triphosphate (ATP) content, increased membrane lipid oxidation, damaged cell membrane integrity, and hyperpolarized cell membrane potential in S. sonnei. The application of linalool to lettuce had no effect on the color of lettuce compared to the control. The sensory evaluation results showed that linalool had an acceptable effect on the sensory quality of lettuce. These findings indicate that linalool played an antibacterial effect against S. sonnei and had potential as a natural antimicrobial for the inhibition of this foodborne pathogen.
RESUMO
Both overt and covert narcissism are positively correlated with conspicuous consumption, which is considered to have the function of satisfying narcissists' dignity needs through showing their status. However, the two types of narcissism are related to different mental health outcomes, and the possible role of conspicuous consumption in these relations has not been explored in depth. Meanwhile, researchers have not reached a consensus on the relation between conspicuous consumption and mental health. The present study recruited a sample of 480 college students to explore the above problems. The correlation analysis showed that both types of narcissism were positively correlated with conspicuous consumption and external value. Overt narcissism was positively correlated with meaning in life, whereas covert narcissism showed the contrary. Conspicuous consumption was negatively correlated with meaning in life but positively correlated with external value. The mediating analysis revealed that neither type of narcissism could help individuals obtain meaning in life through conspicuous consumption directly; however, covert narcissism could help obtain external value through conspicuous consumption for securing meaning in life, whereas overt narcissism could not. The differences between the two types of narcissism and their relation with conspicuous consumption and meaning in life are discussed.
RESUMO
Nesfatin-1 (encoded by NUCB2) is a cardiac peptide possessing protective activities against myocardial ischaemia/reperfusion (MI/R) injury. However, the regulation of NUCB2/nesfatin-1 and the molecular mechanisms underlying its roles in MI/R injury are not clear. Here, by investigating a mouse MI/R injury model developed with transient myocardial ischaemia followed by reperfusion, we found that the levels of NUCB2 transcript and nesfatin-1 amount in the heart were both decreased, suggesting a transcriptional repression of NUCB2/nesfatin-1 in response to MI/R injury. Moreover, cardiac nesfatin-1 restoration reduced infarct size, troponin T (cTnT) level and myocardial apoptosis, supporting its cardioprotection against MI/R injury in vivo. Mechanistically, the Akt/ERK pathway was activated, and in contrast, endoplasmic reticulum (ER) stress was attenuated by nesfatin-1 following MI/R injury. In an in vitro system, similar results were obtained in nesfatin-1-treated H9c2 cardiomyocytes with hypoxia/reoxygenation (H/R) injury. More importantly, the treatment of wortmannin, an inhibitor of Akt/ERK pathway, abrogated nesfatin-1 effects on attenuating ER stress and H/R injury in H9c2 cells. Furthermore, nesfatin-1-mediated protection against H/R injury also vanished in the presence of tunicamycin (TM), an ER stress inducer. Lastly, Akt/ERK inhibition reversed nesfatin-1 effects on mouse ER stress and MI/R injury in vivo. Taken together, these findings demonstrate that NUCB2/nesfatin-1 inhibits MI/R injury through attenuating ER stress, which relies on Akt/ERK pathway activation. Hence, our study provides a molecular basis for understanding how NUCB2/nesfatin-1 reduces MI/R injury.
Assuntos
Estresse do Retículo Endoplasmático , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação da Expressão Gênica , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/metabolismo , Nucleobindinas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Proliferação de Células , Células Cultivadas , MAP Quinases Reguladas por Sinal Extracelular/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão Miocárdica/etiologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Nucleobindinas/genética , Proteínas Proto-Oncogênicas c-akt/genéticaRESUMO
Porphyromonas gingivalis, the key etiologic agent of periodontitis, can be classified into six types (I to V and Ib) based on the fimA genes that encode FimA (a subunit of fimbriae). Accumulated evidence indicates that P. gingivalis expressing Type II fimbriae (Pg-II) is the most frequent isolate from severe periodontitis cases and is more virulent than other types of P. gingivalis. However, during the Pg-II infection process, which specific virulence factors play the key role is still unclear. In this study, we examined the capabilities of three Pg-II strains to invade and modulate the inflammatory cytokine expression of human gingival epithelial cells (GECs) compared to two Pg-I strains. P. gingivalis oligo microarrays were used to compare gene expression profiles of Pg-II strains that invade GECs with Pg-I strains. The differential gene expression of Pg-II was confirmed by quantitative reverse transcription-polymerase chain reaction. Our results showed that all of the Pg-II strains could induce interleukin (IL)-1ß and IL-6 secretion significantly when compared to Pg-I strains. Thirty-seven genes that were specifically expressed during the pathogenic process of Pg-II were identified by a microarray assay. These findings provide a new insight at the molecular level to explain the specific pathogenic mechanism of Pg-II strains.