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BACKGROUND: Dyslipidemia and abnormal cholesterol metabolism are closely related to coronary artery calcification (CAC) and are also critical factors in cardiovascular disease death. In recent years, the atherogenic index of plasma (AIP) has been widely used to evaluate vascular sclerosis. This study aimed to investigate the potential association of AIP between CAC and major adverse cardiovascular events (MACEs). METHODS: This study included 1,121 participants whose CACs were measured by multislice spiral CT. Participants' CAC Agatston score, CAC mass, CAC volume, and number of vessels with CACs were assessed. AIP is defined as the base 10 logarithm of the ratio of triglyceride (TG) concentration to high-density lipoprotein-cholesterol (HDL-C) concentration. We investigated the multivariate-adjusted associations between AIP, CAC, and MACEs. The mediating role of the AIP in CAC and MACEs was subsequently discussed. RESULTS: During a median follow-up of 31 months, 74 MACEs were identified. For each additional unit of log-converted CAC, the MACE risk increased by 48% (HR 1.48 [95% CI 1.32-1.65]). For each additional unit of the AIP (multiplied by 10), the MACEs risk increased by 19%. Causal mediation analysis revealed that the AIP played a partial mediating role between CAC (CAC Agatston score, CAC mass) and MACEs, and the mediating proportions were 8.16% and 16.5%, respectively. However, the mediating effect of CAC volume tended to be nonsignificant (P = 0.137). CONCLUSIONS: An increased AIP can be a risk factor for CAC and MACEs. Biomarkers based on lipid ratios are a readily available and low-cost strategy for identifying MACEs and mediating the association between CAC and MACEs. These findings provide a new perspective on CAC treatment, early diagnosis, and prevention of MACEs.
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HDL-Colesterol , Doença da Artéria Coronariana , Triglicerídeos , Calcificação Vascular , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Triglicerídeos/sangue , HDL-Colesterol/sangue , Calcificação Vascular/sangue , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/epidemiologia , Idoso , Análise de Mediação , Fatores de Risco , Aterosclerose/sangue , Aterosclerose/epidemiologia , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/patologia , Vasos Coronários/patologia , Vasos Coronários/diagnóstico por imagemRESUMO
BACKGROUND: Although the Healthy Eating Index (HEI) is widely recommended to reduce the risk of cardiovascular disease and all-cause death, there are significant differences in physiological and nutritional factors between the sexes. The potential impact of sex on adult dietary health is still poorly understood. The study was designed to assess whether the health benefits of diet differed by sex. METHODS: In a prospective study of 39,567 U.S. adults (51.2% female, age 46.8 ± 17.6 years), we examined sex-specific, multivariable-adjusted associations of HEI with all-cause mortality and cardiovascular disease mortality. Restricted cubic splines (RCS), subgroup analysis, propensity score matching (PSM), random forest feature importance, and sensitivity analysis were also used. RESULTS: During 328,403 person-years of follow-up, a total of 4754 all-cause deaths were recorded, including 1481 cardiovascular deaths. Compared to the lowest quartile of HEI, the all-cause mortality rate of females and males in the highest quartile array decreased by 34% (HR 0.66 [95% CI 0.55-0.8]) and 15% (HR 0.85 [95% CI 0.73-0.99]), respectively. The restricted cubic spline showed a linear inverse association between baseline HEI and all-cause mortality and CVD mortality, with similar sex-specific results. Similarly, component scores were sex-specific for mortality risk, with females benefiting more from diet. The benefits of dairy products, vegetables, and sodium scores on the risk of all-cause death were higher in males and females. However, the benefits of vegetable, sodium, and fatty acid scores on the risk of cardiovascular death were different. CONCLUSIONS: In the adult population of the U.S., there are more opportunities for females to reduce the risk of all-cause mortality and cardiovascular mortality from the same dose of healthy dietary intake than males. These findings could reduce the risk of death by motivating the population, especially females, to consume healthy dietary components, especially vegetables and dairy products.
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Doenças Cardiovasculares , Causas de Morte , Dieta Saudável , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/prevenção & controle , Estudos Prospectivos , Adulto , Dieta Saudável/estatística & dados numéricos , Fatores Sexuais , Idoso , Estados Unidos/epidemiologia , Mortalidade/tendênciasRESUMO
ABSTRACT: Myocardial fibrosis, a common complication of myocardial infarction (MI), is characterized by excessive collagen deposition and can result in impaired cardiac function. The specific role of CD137 in the development of post-MI myocardial fibrosis remains unclear. Thus, this study aimed to elucidate the effects of CD137 signaling using CD137 knockout mice and in vitro experiments. CD137 expression levels progressively increased in the heart after MI, particularly in myofibroblast, which play a key role in fibrosis. Remarkably, CD137 knockout mice exhibited improved cardiac function and reduced fibrosis compared with wild-type mice at day 28 post-MI. The use of Masson's trichrome and picrosirius red staining demonstrated a reduction in the infarct area and collagen volume fraction in CD137 knockout mice. Furthermore, the expression of alpha-smooth muscle actin and collagen I, key markers of fibrosis, was decreased in heart tissues lacking CD137. In vitro experiments supported these findings because CD137 depletion attenuated cardiac fibroblast differentiation, and migration, and collagen I synthesis. In addition, the administration of CD137L recombinant protein further promoted alpha-smooth muscle actin expression and collagen I synthesis, suggesting a profibrotic effect. Notably, the application of an inhibitor targeting the extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathway attenuated the profibrotic effects of CD137L. To conclude, this study provides evidence that CD137 plays a significant role in promoting myocardial fibrosis after MI. Inhibition of CD137 signaling pathways may hold therapeutic potential for mitigating pathological cardiac remodeling and improving post-MI cardiac function.
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Modelos Animais de Doenças , Fibrose , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infarto do Miocárdio , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral , Remodelação Ventricular , Animais , Infarto do Miocárdio/patologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/genética , Infarto do Miocárdio/enzimologia , Infarto do Miocárdio/fisiopatologia , Remodelação Ventricular/efeitos dos fármacos , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/genética , Masculino , Colágeno Tipo I/metabolismo , Colágeno Tipo I/genética , Miofibroblastos/metabolismo , Miofibroblastos/patologia , Miofibroblastos/enzimologia , Sistema de Sinalização das MAP Quinases , Miocárdio/patologia , Miocárdio/metabolismo , Miocárdio/enzimologia , Ligante 4-1BB/metabolismo , Ligante 4-1BB/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Actinas/metabolismo , Células Cultivadas , Transdução de Sinais , Movimento Celular , Camundongos , Função Ventricular Esquerda , Diferenciação Celular , Miócitos Cardíacos/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/enzimologia , Miócitos Cardíacos/efeitos dos fármacosRESUMO
With the in-depth investigation of various diseases, angiogenesis has gained increasing attention. Among the contributing factors to angiogenesis research, endothelial epigenetics has emerged as an influential player. Endothelial epigenetic therapy exerts its regulatory effects on endothelial cells by controlling gene expression, RNA, and histone modification within these cells, which subsequently promotes or inhibits angiogenesis. As a result, this therapeutic approach offers potential strategies for disease treatment. The purpose of this review is to outline the pertinent mechanisms of endothelial cell epigenetics, encompassing glycolysis, lactation, amino acid metabolism, non-coding RNA, DNA methylation, histone modification, and their connections to specific diseases and clinical applications. We firmly believe that endothelial cell epigenetics has the potential to become an integral component of precision medicine therapy, unveiling novel therapeutic targets and providing new directions and opportunities for disease treatment.
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Células Endoteliais , Epigênese Genética , Neovascularização Fisiológica , Humanos , Animais , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Neovascularização Fisiológica/genética , Metilação de DNA , Neovascularização Patológica/genética , Transdução de Sinais , Inibidores da Angiogênese/uso terapêutico , Fenótipo , AngiogêneseRESUMO
Mycoplasma pneumoniae (MP) is one of the main pathogens causing community acquired pneumonia (CAP) in children and adults. Previous pharmacological and clinical studies have shown that Polydatin (PD) exerts anti-inflammatory action by conferring protective benefit in MP pneumonia. However, the mechanism underlying the of PD on MP infection remains unclear. It was found that PD alleviated MP-induced injury by inhibiting caspase-1/gasdermin D (GSDMD)-mediated epithelial pyroptosis. The results demonstrated that PD inhibited the transformation of GSDMD to N-terminal gasdermin-N (GSDMD-N) by decreasing caspase-1 activation, as well as suppressed the formation and secretion of interleukin-1ß (IL-1ß) and interleukin-18 (IL-18), reversed Na, K-ATPase reduction, and suppressed LDH release both in vitro and vivo. Taken together, epithelial pyroptosis in BEAS-2B cells and lung injury in mice were prevented by PD. In conclusion, PD suppressed pulmonary injury triggered by MP infection, by inhibiting the caspase-1/GSDMD-mediated epithelial pyroptosis signaling pathway. Thus, PD may be regarded as a potential therapy for MP-induced inï¬ammation.
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Mycoplasma pneumoniae , Pneumonia por Mycoplasma , Humanos , Criança , Animais , Camundongos , Caspase 1/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Piroptose , Gasderminas , Pneumonia por Mycoplasma/tratamento farmacológico , Proteínas de Ligação a Fosfato/metabolismo , Proteínas Citotóxicas Formadoras de Poros/metabolismoRESUMO
Background: In clinics, Ziwuliuzhu acupuncture is widely considered an effective method of treating insomnia; however, there is currently limited information available regarding its possible mechanisms. Although the method of Ziwuliuzhu acupuncture possesses a unique rhythmic pattern. Objectives: In this study, we have creatively combined the traditional Chinese medicine of Ziwuliuzhu with a modern biological rhythm to investigate the internal mechanism of insomnia. Methods: Pathological tissue from the hypothalamus was analyzed using hematoxylin-eosin staining. The level of TNF (tumor necrosis factor)-α in the SCN (suprachiasmatic nucleus) area of the hypothalamus was detected in situ using the TUNEL fluorescence staining assay. The concentration of hypothalamic melatonin was detected using the enzyme-linked immunosorbent assay (ELISA). The mRNA expression of Clock and Bmal1 was measured using RT-qPCR. Results: In the Ziwuliuzhu acupuncture groups, the structural damage in the hypothalamic neurons was alleviated compared to the model group and the expression of inflammatory factors was reduced. The mRNA expression levels of Clock and Bmal1 were significantly increased (p < 0.05). The concentration of melatonin was significantly increased (p < 0.001). Although there were no significant differences between the treatment groups (diazepam group, Nazi group, Najia group, and routine group) (p > 0.05). Conclusion: Ziwuliuzhu acupuncture alleviated neuronal damage and modulated the inflammatory reaction in the hypothalamus of rats with insomnia. Moreover, Ziwuliuzhu acupuncture increased the expression levels of Clock and Bmal1 mRNA, and MT content. This study has potentially highlighted one of the mechanisms through which Ziwuliuzhu acupuncture can be used to treat insomnia.
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Terapia por Acupuntura , Melatonina , Distúrbios do Início e da Manutenção do Sono , Animais , Ratos , Medicina Tradicional Chinesa , RNA Mensageiro/genética , Distúrbios do Início e da Manutenção do Sono/genética , Distúrbios do Início e da Manutenção do Sono/terapiaRESUMO
BACKGROUND: Cisplatin is a widely used anticancer drug in clinic, but it has a damaging effect on skeletal muscle cells. Clinical observation showed that Yiqi Chutan formula (YCF) had a alleviating effect on cisplatin toxicity. METHODS: In vitro cell model and in vivo animal model were used to observe the damage effect of cisplatin on skeletal muscle cells and verify that YCF reversed cisplatin induced skeletal muscle damage. The levels of oxidative stress, apoptosis and ferroptosis were measured in each group. RESULTS: Both in vitro and in vivo studies have confirmed that cisplatin increases the level of oxidative stress in skeletal muscle cells, thus inducing cell apoptosis and ferroptosis. YCF treatment can effectively reverse cisplatin induced oxidative stress in skeletal muscle cells, thereby alleviating cell apoptosis and ferroptosis, and ultimately protecting skeletal muscle. CONCLUSIONS: YCF reversed cisplatin-induced apoptosis and ferroptosis of skeletal muscle by alleviating oxidative stress.
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Cisplatino , Ferroptose , Animais , Cisplatino/farmacologia , Apoptose , Estresse Oxidativo , Músculo EsqueléticoRESUMO
Ginsenoside Rh3 (GRh3) is a seminatural product obtained by chemical processing after isolation from Chinese herbal medicine that has strong antitumor activity against human tumors. However, its antitumor role remains to be elucidated. The aim of this study is to explore the mechanisms underlying the tumor suppressive activity of GRh3 from the perspective of pyroptosis and ferroptosis. GRh3 eliminates colorectal cancer (CRC) cells by activating gasdermin D (GSDMD)-dependent pyroptosis and suppressing solute carrier family 7 member 11 (SLC7A11), resulting in ferroptosis activation through the Stat3/p53/NRF2 axis. GRh3 suppresses nuclear factor erythroid 2-related factor 2 (NRF2) entry into the nucleus, leading to the decrease of heme oxygenase 1 (HO-1) expression, which in turn promotes NOD-like receptor thermal protein domain associated protein 3 (NLRP3) and caspase-1 expression. Finally, caspase-1 activates GSDMD-dependent pyroptosis. Furthermore, GRh3 prevents NRF2 from entering the nucleus, which suppresses SLC7A11, causing the depletion of glutathione (GSH) and accumulation of iron, lipid reactive oxygen species (ROS) and malondialdehyde (MDA), and eventually leading to ferroptosis in CRC cells. In addition, GRh3 effectively inhibits the proliferation of CRC cells in vitro and in nude mouse models. Collectively, GRh3 triggers pyroptotic cell death and ferroptotic cell death in CRC cells via the Stat3/p53/NRF2 axis with minimal harm to normal cells, showing great anticancer potential.
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Neoplasias Colorretais , Ferroptose , Humanos , Animais , Camundongos , Piroptose , Fator 2 Relacionado a NF-E2/genética , Proteína Supressora de Tumor p53 , Caspase 1 , Glutationa , Camundongos Nus , Neoplasias Colorretais/tratamento farmacológico , Fator de Transcrição STAT3RESUMO
Background: The incidence of cancer-related fatigue (CRF) is increasing, but its lack of clear pathogenesis makes its prevention and treatment difficult. Therefore, it is of great significance to clarify the pathogenesis of CRF and find effective methods to treat it. Methods: The CRF model was established by intraperitoneal injection of LLC cells in ICR mice to explore the pathogenesis of CRF and verify the therapeutic effect of the Yifei-Sanjie pill (YFSJ). The active components of YFSJ were found by LC/MS, the in vitro inflammatory infiltration model of skeletal muscle was constructed by TNF-α and C2C12 myoblasts, and the results of in vivo experiments were verified by this model. Results: Behavioral analysis results showed that YFSJ alleviated CRF; histological examination results showed that YFSJ could reverse the tumor microenvironment leading to skeletal muscle injury; ELISA and RNA-seq results showed that the occurrence of CRF and the therapeutic effect of YFSJ were closely related to the tumor inflammatory microenvironment; IHC and WB results showed that the occurrence of CRF and the therapeutic effect of YFSJ were closely related to the Stat3-related signaling pathway and autophagy. Conclusions: YFSJ can reduce the level of inflammation in the tumor microenvironment in vivo, inhibit the abnormal activation of the Stat3/HIF-1α/BNIP3 signaling pathway induced by tumor-related inflammation, thereby inhibiting the overactivation of mitophagy in skeletal muscle, and finally alleviate CRF. Quercetin, one of the components of YFSJ, plays an important role in inhibiting the phosphorylation activation of Stat3.
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Luteolin, which is a natural flavonoid, has anti-inflammatory, antioxidant, and anticancer properties. Numerous studies have proven that luteolin inhibits the growth of many types of cancer cells by promoting apoptosis, autophagy, and cell cycle arrest in tumour cells. However, in vivo research on this topic has been limited. In addition, other studies have shown that luteolin exerts a good inhibitory effect on apoptosis-resistant cancer cells. While existing studies have not completely elucidated the mechanism underlying this phenomenon, we assume that luteolin, which is a natural compound that exerts its effects through various mechanisms, may have the potential to inhibit tumour growth. In our study, we proved that luteolin exerted a good inhibitory effect on the proliferation of colon cancer cells according to CCK8 and EdU fluorescence assays, and the same conclusion was drawn in animal experiments. In addition, we found that luteolin, which is an antioxidant, unexpectedly promoted oxidative stress as shown by measuring the levels of oxidative balance-related indicators, such as reactive oxygen species (ROS), SOD, H2O2 and GSH. However, the decreased oxidation of luteolin-treated HT-29 cells after treatment with the active oxygen scavenger NAC did not reverse the inhibition of cell growth. However, the Caspase1 inhibitor VX765 did reverse the inhibition of cell growth. Western blotting analysis showed that luteolin treatment increased the expression of Caspase1, Gasdermin D and IL-1ß, which are members of the pyroptosis signalling pathway, in colon cancer cells. We further intuitively observed NLRP3/Gasdermin D colocalization in luteolin-treated HT-29 cells and mouse tumour tissues by immunofluorescence. These results suggest that luteolin inhibits the proliferation of colon cancer cells through a novel pathway called pyroptosis. This study provides a new direction for the development of natural products that inhibit tumour growth by inducing pyroptosis.
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Chemotherapy-related fatigue (CRF), one of the most severe adverse effects observed in cancer patients, has been theoretically related to oxidative stress, and antioxidant treatment might be one of the most valuable therapeutic approaches. However, there are still few effective pharmacological therapies. Yifei Sanjie pills (YFSJ), a classical formula used to treat lung cancer as complementary and alternative medicine, have been proved to alleviate CRF of lung cancer patients in clinical practices. However, the underlying mechanisms have not been clarified. In this study, our data showed that YFSJ alleviated CRF presented as reversing the decline of swimming time and locomotor activity induced by cisplatin (DDP). Moreover, YFSJ significantly reduces the accidence of mitophagy and mitochondrial damage and reduces apoptosis in skeletal muscle tissues caused by DDP. It probably works by decreasing the oxidative stress, inhibiting the activation of the AMPK/mTOR pathway, decreasing protein expression levels of Beclin1 and other autophagy-related proteins, and attenuating the activation of Cytochrome c (cyto. C), Cleaved Caspase-9 (c-Casp 9), and other apoptosis-related proteins. Furthermore, YFSJ enhanced DDP sensitivity by specifically promoting oxidative stress and activating apoptosis and autophagy in the tumor tissues of mice. It was also found that YFSJ reduced the loss of body weight caused by DDP, reversed the ascent of serum concentrations of alanine aminotransferase (ALT), aminotransferase (AST), and creatinine (CREA), increased the spleen index, and prolonged the survival time of mice. Taken together, these results revealed that YFSJ could alleviate CRF by reducing mitophagy and apoptosis induced by oxidative stress in skeletal muscle; these results also displayed the effects of YFSJ on enhancing chemotherapy sensitivity, improving quality of life, and prolonging survival time in lung cancer mice received DDP chemotherapy.
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Colorectal cancer (CRC) is a severe threat to human health. Ginsenosides such as ginsenoside Rh4 have been widely studied in the antitumor field. Here, we investigated the antiproliferative activity and mechanism of Rh4 against CRC in vivo and in vitro. The CRC xenograft model showed that Rh4 inhibited xenograft tumor growth with few side effects (p < 0.05). As determined by MTT colorimetric assays, Western blotting, and immunohistochemical analysis, Rh4 effectively inhibited CRC cell proliferation through autophagy and ferroptosis (p < 0.05). Rh4 significantly upregulated autophagy and ferroptosis marker expression in CRC cells and xenograft tumor tissues in the present study (p < 0.05). Interestingly, the ferroptosis inhibitor ferrostatin-1 (Fer-1) reversed Rh4-induced ferroptosis (p < 0.05). Moreover, the autophagy inhibitor 3-methyladenine (3-MA) also reversed Rh4-induced ferroptosis (p < 0.05). These results indicate that Rh4-induced ferroptosis is regulated via the autophagy pathway. In addition, Rh4 increased reactive oxygen species (ROS) accumulation, leading to the activation of the ROS/p53 signaling pathway (p < 0.05). Transcriptome sequencing also confirmed this (p < 0.05). Moreover, the ROS scavenger N-acetyl-cysteine (NAC) reversed the inhibitory effect of Rh4 on CRC cells (p < 0.05). Therefore, this study proves that Rh4 inhibits cancer cell proliferation by activating the ROS/p53 signaling pathway and activating autophagy to induce ferroptosis, which provides necessary scientific evidence of the great anticancer potential of Rh4.
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Mycoplasma pneumoniae (MP) infection is a common cause of community-acquired pneumonia in children. Furthermore, many children with Mycoplasma pneumoniae pneumonia (MPP) have recurrent wheezing and reduced small airway function after their clinical symptoms have resolved, eventually leading to asthma. MPP can trigger immune disorders and systemic inflammatory responses. Hence, the intestine is the largest immune organ of the body. Therefore, we sought to investigate whether the alteration of intestinal flora is correlated with the development of wheezing in children with MPP. We collected 30 healthy children as group A, 50 children with nonwheezing MPP as group B, and 50 children with wheezing MPP as group C. We found that the percentage of eosinophil cells (EC) was significantly higher in group C than that in group B for routine blood tests and serum inflammatory factors. The serum cytokines, including IL-4, IL-17, TNF-α, and TGF-ß, were significantly higher in group C than in group B. In addition, the level of IL-10 was significantly lower in group C than in group B. The distribution characteristics of intestinal flora strains in children with MPP were detected by sequencing of 16S rRNA gene amplicon sequencing. There were differences in the abundance of intestinal flora between children with MPP and healthy children, with lower abundance of Ruminococcus flavefaciens, Clostridium butyricum, Lactobacillus, and Bifidobacterium in the intestine of children with MPP compared to healthy children. The abundance of Ruminococcus flavefaciens and Clostridium butyricum was significantly lower in the intestine of children with wheezing MPP compared to children without wheezing MPP. In the correlation analysis between children with MPP and inflammatory factors, Ruminococcus flavefaciens was found to be negatively correlated with IL-17. Clostridium butyricum was negatively correlated with L-4, IL-17, TNF-α, and TGF-ß; however, it positively correlated with IL-10. Thus, it was concluded that alterations in intestinal flora play a crucial role in the immune response to MPP, where a significant decline in intestinal Ruminococcus flavefaciens and Clostridium butyricum leads to an exacerbation of the inflammatory responses, which may promote the development of children with wheezing MPP.
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Microbioma Gastrointestinal , Pneumonia por Mycoplasma , Criança , Humanos , Mycoplasma pneumoniae/genética , Pneumonia por Mycoplasma/microbiologia , RNA Ribossômico 16S , Sons RespiratóriosRESUMO
Stimulation of macrophages with lipopolysaccharide (LPS) leads to the production of cytokines that elicit massive liver apoptosis. We investigated the in vivo role of stress-responsive transcription factors (SRTFs) in this process focusing on the precipitating events that are sensitive to a cell-permeant peptide inhibitor of SRTF nuclear import (cSN50). In the absence of cSN50, mice challenged with LPS displayed very early bursts of inflammatory cytokines/chemokines, tumor necrosis factor alpha (1 h), interleukin 6 (2 h), interleukin 1 beta (2 h), and monocyte chemoattractant protein 1 (2 h). Activation of both initiator caspases 8 and 9 and effector caspase 3 was noted 4 h later when full-blown DNA fragmentation and chromatin condensation were first observed (6 h). At this time an increase of pro-apoptotic Bax gene expression was observed. It was preceded by a decrease of anti-apoptotic Bcl2 and BclX(L) gene transcripts. Massive apoptosis was accompanied by microvascular injury manifested by hemorrhagic necrosis and a precipitous drop in blood platelets observed at 6 h. An increase in fibrinogen/fibrin degradation products and a rise in plasminogen activator inhibitor 1 occurred between 4 and 6 h. Inhibition of SRTFs nuclear import with the cSN50 peptide abrogated all these changes and increased survival from 7 to 71%. Thus, the nuclear import of SRTFs induced by LPS is a prerequisite for activation of the genetic program that governs cytokines/chemokines production, liver apoptosis, microvascular injury, and death. These results should facilitate the rational design of drugs that protect the liver from inflammation-driven apoptosis.
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Transporte Ativo do Núcleo Celular/fisiologia , Apoptose/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Fígado , Peptídeos/farmacologia , Fatores de Transcrição/metabolismo , Animais , Apoptose/fisiologia , Caspases/metabolismo , Linhagem Celular , Quimiocinas/imunologia , Citocinas/imunologia , Feminino , Hepatócitos/metabolismo , Lipopolissacarídeos/administração & dosagem , Lipopolissacarídeos/imunologia , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/imunologia , Fígado/patologia , Macrófagos/citologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Peptídeos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Taxa de Sobrevida , Proteína X Associada a bcl-2 , Proteína bcl-XRESUMO
Targeting of peptides, proteins, and other functional cargo into living cells is contingent upon efficient transport across the plasma membrane barrier. We have harnessed the signal sequence hydrophobic region (SSHR) to deliver functional cargoes to cultured cells and to experimental animals. We now report evidence that two chirally distinct forms of SSHR composed of all l or all d amino acids showed similar membrane-translocating activity as assessed by confocal microscopy, flow cytometry, and direct fluorescence measurement. An attached nuclear localization sequence ferried by the SSHR enantiomers displayed similar intracellular function by inhibiting inducible nuclear import of transcription factor nuclear factor kappa B and suppressing nuclear factor kappa B-dependent gene expression of cytokines. A nuclear localization sequence comprised of a positively charged cluster of amino acids was rapidly translocated by SSHR enantiomers to the interior of unilamellar phospholipid vesicles. These findings indicate that the SSHR translocates functional peptides directly through the plasma membrane phospholipid bilayer without involving chirally specific receptor/transporter mechanisms. This mechanism of SSHR translocation is suitable for facile delivery of biologically active peptides for cell-based and animal-based functional proteomic studies.