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Pregnancy is characterized by significant immunological changes and a cytokine profile, as well as vitamin deficiencies that can cause problems for the correct development of a fetus. Defensins are small antimicrobial peptides that are part of the innate immune system and are involved in several biological activities. Following that, this study aims to compare the levels of various cytokines and to investigate the role of defensins between pregnant women with confirmed COVID-19 infection and pregnant women without any defined risk factor. TNF-α, TGF-ß, IL-2 and IL-10, ß-defensins, have been evaluated by gene expression in our population. At the same time, by ELISA assay IL-6, IL-8, defensin alpha 1, defensin beta 1 and defensin beta 4 have been measured. The data obtained show that mothers affected by COVID-19 have an increase in pro-inflammatory factors (TNF-α, TGF-ß, IL-2, IL-6, IL-8) compared to controls; this increase could generate a sort of "protection of the fetus" from virus attacks. Contemporarily, we have an increase in the anti-inflammatory cytokine IL-10 and an increase in AMPs, which highlights how the mother's body is responding to the viral attack. These results allow us to hypothesize a mechanism of "trafficking" of antimicrobial peptides from the mother to the fetus that would help the fetus to protect itself from the infection in progress.
Assuntos
COVID-19 , alfa-Defensinas , beta-Defensinas , Citocinas , Feminino , Humanos , Interleucina-10 , Interleucina-2 , Interleucina-6 , Interleucina-8 , Gravidez , Gestantes , Fator de Crescimento Transformador beta , Fator de Necrose Tumoral alfaRESUMO
In the last few years, a significant increase of childhood obesity incidence unequally distributed within countries and population groups has been observed, thus representing an important public health problem associated with several health and social consequences. Obese children have more than a 50% probability of becoming obese adults, and to develop pathologies typical of obese adults, that include type 2-diabetes, dyslipidemia and hypertension. Also environmental factors, such as reduced physical activity and increased sedentary activities, may also result in increased caloric intake and/or decreased caloric expenditure. In the present review, we aimed to identify and describe a specific panel of parameters in order to evaluate and characterize the childhood obesity status useful in setting up a preventive diagnostic approach directed at improving health-related behaviors and identifying predisposing risk factors. An early identification of risk factors for childhood obesity could definitely help in setting up adequate and specific clinical treatments.
Assuntos
Exercício Físico , Laboratórios/normas , Microbiota , Obesidade Infantil/diagnóstico , Obesidade Infantil/terapia , Criança , Predisposição Genética para Doença , Humanos , Obesidade Infantil/genéticaRESUMO
The need to evaluate the health status of an athlete represents a crucial aim in preventive and protective sports science in order to identify the best diagnostic strategy to improve performance and reduce risks related to physical exercise. In the present review we aim to define the main biochemical and haematological markers that vary significantly during and after sports training to identify risk factors, at competitive and professional levels and to highlight the set up of a specific parameter's panel for elite athletes. Moreover, we also intend to consider additional biomarkers, still under investigation, which could further contribute to laboratory sports medicine and provide reliable data that can be used by athlete's competent staff in order to establish personal attitudes and prevent sports injuries.
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Aptidão Física/fisiologia , Medicina Esportiva/métodos , Medicina Esportiva/tendências , Atletas , Técnicas de Laboratório Clínico/métodos , Exercício Físico/fisiologia , Humanos , EsportesRESUMO
Crohn's disease (CD) is a chronic inflammation of the intestinal mucosa, characterized by periods of acute recurrence and remission. Depending on the specific region affected, CD is classified as ileal CD or colonic CD. It is largely accepted that the intestinal microbiota is involved in the onset of the pathology. Indeed, a reduced immune tolerance to components of the intestinal commensal microbiota and inflammation of the intestinal barrier typifies patients with CD. Several studies have shown defective expression of intestinal antimicrobial peptides (AMPs) in patients with CD compared to controls, particularly defensins. A reduction in α-defensins is observed in ileal CD, while ß-defensins are increased in colonic CD. In addition to an immunological basis, the disease is frequently associated with genetic alterations including mutations of NOD2 gene. Several therapeutic strategies to circumvent the dysfunction observed in CD are currently under investigation. These include the use of delivery systems to administer endogenous AMPs and the engineering of peptidomimetics that could ameliorate the severity of CD. In this review, the role defensins play in CD and the strategies aimed at overcoming bacterial resistance will be discussed.
Assuntos
Doença de Crohn/metabolismo , Doença de Crohn/microbiologia , Defensinas/metabolismo , Mucosa Intestinal/microbiologia , Microbiota , Animais , Peptídeos Catiônicos Antimicrobianos/química , Doença de Crohn/imunologia , Defensinas/imunologia , Modelos Animais de Doenças , Farmacorresistência Bacteriana , Humanos , Íleo/metabolismo , Íleo/microbiologia , Sistema Imunitário , Inflamação , Mucosa Intestinal/imunologia , Intestino Delgado/metabolismo , Intestino Delgado/microbiologia , Camundongos , alfa-Defensinas , beta-DefensinasRESUMO
Antimicrobial peptides (AMPs) play a pivotal role in the innate immune responses to Helicobacter pylori (Hp) in humans. ß-Defensins, a class of cationic arginine-rich AMPs, are small peptides secreted by immune cells and epithelial cells that exert antimicrobial activity against a broad spectrum of microorganisms, including Gram-positive and Gram-negative bacteria and fungi. During Hp infections, AMP expression is able to eradicate the bacteria, thereby preventing Hp infections in gastrointestinal tract. It is likely that gastric ß-defensins expression is increased during Hp infection. The aim of this review is to focus on increased knowledge of the role of ß-defensins in response to Hp infection. We also briefly discuss the potential use of AMPs, either alone or in combination with conventional antibiotics, for the treatment of Hp infection.
Assuntos
Infecções por Helicobacter/microbiologia , Helicobacter pylori/efeitos dos fármacos , Interações Hospedeiro-Patógeno , beta-Defensinas/farmacologia , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/metabolismo , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Células Epiteliais/metabolismo , Gastrite/etiologia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/patogenicidade , Humanos , Neoplasias Gástricas/etiologia , Relação Estrutura-Atividade , Fatores de Virulência , beta-Defensinas/química , beta-Defensinas/metabolismo , beta-Defensinas/uso terapêuticoRESUMO
Lipopolysaccharide (LPS) is one of the principal bacterial products known to elicit inflammation. Cells of myeloid lineage such as monocytes and macrophages, but also epithelial cells give rise to an inflammatory response upon LPS stimulation. This phenomenon implies reprogramming of cell specific gene expression that can occur through different mechanisms including epigenetic modifications. Given their intrinsic nature, epigenetic modifications may be involved both in the acute response to LPS and in the establishment of a preconditioned genomic state (epigenomic memory) that may potentially influence the host response to further contacts with microorganisms. Information has accumulated during the last years aimed at elucidating the epigenetic mechanisms which underlie the cellular LPS response. These findings, summarized in this chapter, will hopefully be a good basis for a definition of the complete cascade of LPS-induced epigenetic events and their biological significance in different cell types.
Assuntos
Bactérias/metabolismo , Infecções Bacterianas/metabolismo , Epigênese Genética , Lipopolissacarídeos/metabolismo , Animais , Infecções Bacterianas/genética , Infecções Bacterianas/patologia , HumanosRESUMO
The hemostatic system is characterized by a delicate balance between pro- and anticoagulant forces, and the smallest alteration can cause serious events such as hemorrhages or thrombosis. Although exercise has been shown to play a protective role in athletes, several factors may increase the risk of developing venous thromboembolism (VTE), including hemoconcentration induced by exertion, immobilization following sports injuries, frequent long-distance flights, dehydration, and the use of oral contraceptives in female athletes. Biomarkers such as D-dimer, Factor VIII, thrombin generation, inflammatory cytokines, and leukocyte count are involved in the diagnosis of deep vein thrombosis (DVT), although their interpretation is complex and may indicate the presence of other conditions such as infections, inflammation, and heart disease. Therefore, the identification of biomarkers with high sensitivity and specificity is needed for the screening and early diagnosis of thromboembolism. Recent evidence about the correlation between the intensity of physical activity and VTE is divergent, whereas the repeated gestures in sports such as baseball, hockey, volleyball, swimming, wrestling, or, on the other hand, soccer players, runners, and martial art training represent a risk factor predisposing to the onset of upper and lower DVT. Anticoagulant therapy is the gold standard, reducing the risk of serious complications such as pulmonary embolism. The aim of this review is to provide a general overview about the interplay between physical exercise and the risk of thromboembolism in athletes, focusing on the main causes of thrombosis in professional athletes and underlying the need to identify new markers and therapies that can represent a valid tool for safeguarding the athlete's health.
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The lack of reliable methods for preeclampsia (PE) early diagnosis limits the opportunities for timely prevention, diagnosis and treatment. This study aims to identify the alterations of biochemical parameters and the immune system activity to build a panel of markers that can support preeclampsia diagnosis. For this study, we recruited 30 pregnant women: 10 healthy pregnant women (CTR); 10 pregnant women with early preeclampsia (EP); 10 pregnant women with late preeclampsia (LP). We evaluated lipid profile and, by gene expression, we assessed PCSK9, IL-2, IL-6, IL-8, IL-10, TNF-α and TGF-ß. Moreover, we evaluated both the serum and gene levels of the defensins HBD-1, HBD-2, HBD-4 and HNP-1. Our results showed an increase in gene expression levels of IL-6 and IL-8 in EP compared to LP (IL-6: median 11.7 vs 3.3, p = 0.005; IL-8: median 634.1 vs 214.1, p = 0.013) and to CTR (IL-6: median 11.7 vs 0.5, p < 0.001; IL-8: median 634.1 vs 225.6, p = 0.012), highlighting a massive activation of immune system in case of more severe preeclampsia. Furthermore, higher serum levels of HBD1 in LP compared to CTR (median: 278.8 vs 67.8, p = 0.005) and to EP (median: 278.8 vs 68.6, p = 0.001) might indicate that the same immune system puts in action protective actions to prevent adverse outcome in these cases. Finally, gene expression levels of PCSK9 decreased significantly in women with EP compared to controls and to LP (median: 0.2 vs 0.9, p = 0.010; median: 0.2 vs 1.2, p = 0.012), causing a decrease in circulating LDL-c necessary for the synthesis of placental hormones.
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The PATZ1 gene encoding a POZ/AT-hook/Kruppel zinc finger (PATZ) transcription factor, is considered a cancer-related gene because of its loss or misexpression in human neoplasias. As for other POZ/domain and Kruppel zinc finger (POK) family members, the transcriptional activity of PATZ is due to the POZ-mediated oligomer formation, suggesting that it might be not a typical transactivator but an architectural transcription factor, thus functioning either as activator or as repressor depending on the presence of proteins able to interact with it. Therefore, to better elucidate PATZ function, we searched for its molecular partners. By yeast two-hybrid screenings, we found a specific interaction between PATZ and BCL6, a human oncogene that plays a key role in germinal center (GC) derived neoplasias. We demonstrate that PATZ and BCL6 interact in germinal center-derived B lymphoma cells, through the POZ domain of PATZ. Moreover, we show that PATZ is able to bind the BCL6 regulatory region, where BCL6 itself acts as a negative regulator, and to contribute to negatively modulate its activity. Consistently, disruption of one or both Patz1 alleles in mice causes focal expansion of thymus B cells, in which BCL6 is up-regulated. This phenotype was almost completely rescued by crossing Patz1(+/-) with Bcl6(+/-) mice, indicating a key role for Bcl6 expression in its development. Finally, a significant number of Patz1 knock-out mice (both heterozygous and homozygous) also develop BCL6-expressing lymphomas. Therefore, the disruption of one or both Patz1 alleles may favor lymphomagenesis by activating the BCL6 pathway.
Assuntos
Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Proteínas Repressoras/metabolismo , Animais , Sequência de Bases , Linhagem Celular , Imunoprecipitação da Cromatina , Primers do DNA , Humanos , Linfoma de Células B/genética , Linfoma de Células B/patologia , Camundongos , Camundongos Knockout , Ligação Proteica , Proteínas Proto-Oncogênicas c-bcl-6 , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
One of the most fascinating aspects of the field of epigenetics is the emerging ability of environmental factors to trigger epigenetic changes in eukaryotic cells, thus contributing to transient or stable, and potentially heritable, changes in gene expression program in the absence of alteration in DNA sequence. Epigenetic response may result in cell adaptation to environmental stimuli or, in some instances, may contribute to generation or progression of different kind of diseases. A paradigmatic case of disease that is accompanied by multiple epigenetic alterations is gastric cancer, among other relevant examples. In turn, Helicobacter pylori (Hp) infection has been associated as a leading cause of gastric cancer. One possible hypothesis is that Hp-gastric cell interaction initiates an epigenetic reprogramming of host cell genome that may favor tumorigenesis. Accordingly, an abundance of experimental evidence indicates that several epigenetic alterations underlie the gastric cancerogenesis process and that these alterations represent one of the major hallmarks of gastric cancer. However, several critical questions remain unanswered: Does Hp directly provoke epigenetic alterations? Which mechanisms underlie these phenomena? Based on currently available data, it is often arduous to discriminate between the epigenetic modifications directly triggered by Hp-gastric cell interaction and those alterations that are mediated by inflammation process or by many other molecular and genetic events occurring during the gastric cancer progression. We will review our present knowledge of epigenetic modifications and alterations proven to occur in host cells as a direct consequence of Hp infection.
Assuntos
Epigênese Genética , Células Epiteliais/microbiologia , Regulação da Expressão Gênica , Helicobacter pylori/fisiologia , Interações Hospedeiro-Patógeno , Neoplasias Gástricas/microbiologia , HumanosRESUMO
Intense physical activity can induce metabolic changes that modify specific biochemical biomarkers. In this scenario, the purpose of our study was to evaluate how intense physical activity can affect oxidative metabolism. Following this, fifteen professional basketball players and fifteen sedentary controls were recruited and subjected to two samplings of serum and urine in the pre-season (September) and two months after the start of the competitive season (November). Our results have shown an increase in athletes compared to controls in CK and LDH in September (respectively, p-value 0.003 and p-value < 0.001) and in November (both p-value < 0.001), whereas ALT is increased only in November (p-value 0.09). GGT serum levels were decreased in athletes compared to controls in both months (in September p-value 0.001 and in November p-value < 0.001). A gene expression analysis, carried out using RT-PCR, has revealed that IL-2, IL-6, IL-8, xCT and GCLM are increased in athletes in both months (p-value < 0.0001), while IL-10 and CHAC1 are increased only in September if compared to the controls (respectively, p-value 0.040 and p-value < 0.001). In conclusion, physical activity creates an adaptation of the systems involved in oxidative metabolism but without causing damage to the liver or kidney. This information could be of help to sports doctors for the prevention of injuries and illnesses in professional athletes for the construction of the athlete's passport.
Assuntos
Antioxidantes , Basquetebol , Humanos , Antioxidantes/metabolismo , Atletas , Exercício Físico , Rim/metabolismoRESUMO
Inducible nitric oxide synthase (iNOS) expression is altered in gastrointestinal diseases. Helicobacter pylori (Hp) infection may have a critical role in iNOS disregulation. We undertook this study to investigate possible chromatin changes occurring early during iNOS gene activation as a direct consequence of Hp-gastric cells interaction. We show that Hp infection is followed by different expression and chromatin modifications in gastric cells including (1) activation of iNOS gene expression, (2) chromatin changes at iNOS promoter including decreased H3K9 methylation and increased H3 acetylation and H3K4 methylation levels, (3) selective release of methyl-CpG-binding protein 2 from the iNOS promoter. Moreover, we show that Hp-induced activation of iNOS is delayed, but not eliminated, by the treatment with LSD1 inhibitors. Our data suggest a role for specific chromatin-based mechanisms in the control of human iNOS gene expression upon Hp exposure.
Assuntos
Células Epiteliais/metabolismo , Mucosa Gástrica/citologia , Helicobacter pylori/patogenicidade , Histonas/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Regiões Promotoras Genéticas/genética , Linhagem Celular Tumoral , Cromatina/metabolismo , Ativação Enzimática , Mucosa Gástrica/metabolismo , Humanos , Óxido Nítrico Sintase Tipo II/genéticaRESUMO
Background: Childhood obesity (CO) is a serious medical condition affecting approximately 120 million children and adolescents worldwide. It is characterized by a persistent inflammatory state with inflammatory markers overexpressed, which in turn leads to a higher cardiovascular risk. It is well known that physical exercise reduces the inflammatory state in obese children. In the present study, we evaluated various biochemical parameters in obese children performing physical exercise compared to a group of obese sedentary children. Hence, the objective is to identify a panel of biomarkers to prevent numerous obesity-related complications. Methods: We examined two populations: 44 sedentary obese children (OSe), recruited on 5 November 2018 from Santobono−Pausilipon Children's Hospital, Naples (Italy) of age = 11 ± 3.3 and 30 obese children who practice sport (OSp) of age = 10 ± 2.5. We observed a significant variation in some biochemical parameters such as white blood cells, C-reactive protein (CRP), glycemia and insulinemia. Moreover, we determined the levels of interleukins, chemokines and defensins by ELISA assay. Results: Our results showed a reduction in serum level of glycemia (p-value < 0.001), neutrophils (p-value < 0.05) and CRP (p-value < 0.05), whereas no relevant variations have been reported in insulin levels. Moreover, we found a decrease in serum levels of PDGF-ß (p-value < 0.05), IL-9 (p-value < 0.01), IL-6 (p-value < 0.0001), IL-8 (p-value < 0.0001), IP-10 (p-value < 0.01), Eotaxin (p-value < 0.0001) and GM-CSF (p-value < 0.01) in OSp population in comparison to OSe. At the same time, we did not observe any significant variation in serum levels of IL-1ra and IL-17 between the two populations. On the other hand, we found an increase in HNP-1 (p-value < 0.0001) and HBD1 (p-value < 0.01) in OSp if compared to OSe. Conclusions: This study shed light on the role of physical exercise on CO, demonstrating in our population that an early evaluation of some biochemical parameters could be an assumption to prescribe physical exercise in order to monitor and prevent childhood obesity and related disorders.
Assuntos
Doenças Cardiovasculares , Obesidade Infantil , Adolescente , Humanos , Criança , Obesidade Infantil/complicações , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/etiologia , Fatores de Risco , Exercício Físico , Biomarcadores , Proteína C-Reativa , Fatores de Risco de Doenças Cardíacas , Itália/epidemiologia , Sistema Imunitário , Índice de Massa CorporalRESUMO
Physical activity, combined with adequate nutrition, is considered a protective factor against cardiovascular disease, musculoskeletal disorders, and intestinal dysbiosis. Achieving optimal performance requires a significantly high energy expenditure, which must be correctly supplied to avoid the occurrence of diseases such as muscle injuries, oxidative stress, and heart pathologies, and a decrease in physical performance during competition. Moreover, in sports activities, the replenishment of water, vitamins, and minerals consumed during training is essential for safeguarding athletes' health. In this scenario, vitamins play a pivotal role in numerous metabolic reactions and some muscle biochemical adaptation processes induced by sports activity. Vitamins are introduced to the diet because the human body is unable to produce these micronutrients. The aim of this review is to highlight the fundamental role of vitamin supplementation in physical activity. Above all, we focus on the roles of vitamins A, B6, D, E, and K in the prevention and treatment of cardiovascular disorders, muscle injuries, and regulation of the microbiome.
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Microbiota , Vitaminas , Atletas , Dieta , Humanos , Minerais , Miocárdio/metabolismo , Vitaminas/metabolismoRESUMO
COX-2 expression is altered in gastrointestinal diseases. Helicobacter pylori (Hp) infection may have a critical role in COX-2 disregulation. We undertook this study to investigate possible chromatin and DNA methylation changes occurring early during COX-2 gene activation as a direct consequence of Hp-gastric cells interaction. We show that Hp infection is followed by different expression, chromatin and DNA methylation changes including: (i) biphasic activation of COX-2 gene; (ii) rapid remodulation of HDACs expression and activity, increased acetylation and release of HDAC from COX-2 promoter; (iii) transient gradual increase of H3 acetylation and H3K4 dimethylation and decrease of H3K9 dimethylation; (iv) late and long-lasting increase of H3K27 trimethylation; (v) rapid cyclical DNA methylation/demethylation events at 8 specific CpG sites (-176, -136, +25, +36, +57, +82, +198, +231) surrounding the COX-2 gene transcriptional start site. Our data indicate that specific chromatin and DNA methylation changes occur at COX-2 gene in the first phases of Hp exposure in cultured gastric cells as a primary response to host-parasite interaction.
Assuntos
Cromatina/metabolismo , Ciclo-Oxigenase 2/biossíntese , Metilação de DNA , Helicobacter pylori/patogenicidade , Interações Hospedeiro-Patógeno , Linhagem Celular , Células Epiteliais/microbiologia , Regulação da Expressão Gênica , Histona Desacetilases/metabolismo , Histonas/metabolismo , Humanos , MetilaçãoRESUMO
Antimicrobial peptides (AMPs), α- and ß-defensins, possess antiviral properties. These AMPs achieve viral inhibition through different mechanisms of action. For example, they can: (i) bind directly to virions; (ii) bind to and modulate host cell-surface receptors, disrupting intracellular signaling; (iii) function as chemokines to augment and alter adaptive immune responses. Given their antiviral properties and the fact that the development of an effective coronavirus disease 2019 (COVID-19) treatment is an urgent public health priority, they and their derivatives are being explored as potential therapies against COVID-19. These explorations using various strategies, range from their direct interaction with the virus to using them as vaccine adjuvants. However, AMPs do not work in isolation, specifically in their role as potent immune modulators, where they interact with toll-like receptors (TLRs) and chemokine receptors. Both of these receptors have been shown to play roles in COVID-19 pathogenesis. In addition, it is known that a healthy lifestyle accompanied by controlled physical activity can represent a natural weapon against COVID-19. In competitive athletes, an increase in serum defensins has been shown to function as self-protection from the attack of microorganisms, consequently a controlled physical activity could act as a support to any therapies in fighting COVID-19. Therefore, including information on all these players' interactions would produce a complete picture of AMP-based therapies' response.
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Coronaviruses (CoVs) represent a large family of RNA viruses that can infect different living species, posing a global threat to human health. CoVs can evade the immune response, replicate within the host, and cause a rapid immune compromise culminating in severe acute respiratory syndrome. In humans, the immune system functions are influenced by physical activity, nutrition, and the absence of respiratory or cardiovascular diseases. This review provides an in-depth study between the interactions of the immune system and coronaviruses in the host to defend against CoVs disease.
Assuntos
COVID-19 , Doenças Cardiovasculares , Dieta , Exercício Físico , Sistema Imunitário , Doenças Respiratórias , COVID-19/epidemiologia , Doenças Cardiovasculares/epidemiologia , Humanos , Doenças Respiratórias/epidemiologiaRESUMO
BACKGROUND: The release of LPS by bacteria stimulates both immune and specific epithelial cell types to release inflammatory mediators. It is known that LPS induces the release of IL-8 by intestinal mucosal cells. Because it is now emerging that bacteria may induce alteration of epigenetic patterns in host cells, we have investigated whether LPS-induced IL-8 activation in human intestinal epithelial cells involves changes of histone modifications and/or DNA methylation at IL-8 gene regulatory region. RESULTS: RT-PCR analysis showed that IL-8 mRNA levels rapidly increase after exposure of HT-29 cells to LPS. DNA demethylating agents had no effects on IL-8 expression, suggesting that DNA methylation was not involved in IL-8 gene regulation. Consistently we found that 5 CpG sites located around IL-8 transcription start site (-83, -7, +73, +119, +191) were unmethylated on both lower and upper strand either in LPS treated or in untreated HT-29 cells, as well as in normal intestinal mucosa.Conversely, pretreatment of HT-29 cells with deacetylase inhibitors strengthened the LPS-mediated IL-8 activation. Inhibitors of histone deacetylases could induce IL-8 mRNA expression also in the absence of LPS, suggesting that chromatin modifications could be involved in IL-8 gene regulation. Chromatin immunoprecipitation analyses showed that, concurrently with IL-8 activation, transient specific changes in H3 acetylation and H3K4, H3K9 and H3K27 methylation occurred at IL-8 gene promoter during LPS stimulation. Changes of H3-acetyl, H3K4me2 and H3K9me2 levels occurred early, transiently and corresponded to transcriptional activity, while changes of H3K27me3 levels at IL-8 gene occurred later and were long lasting. CONCLUSION: The results showed that specific chromatin modifications occurring at IL-8 gene, including histone H3 acetylation and methylation, mark LPS-mediated IL-8 activation in intestinal epithelial cells while it is unlikely that DNA methylation of IL-8 promoter is directly involved in IL-8 gene regulation in these cells.
Assuntos
Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Histonas/metabolismo , Interleucina-8/metabolismo , Lipopolissacarídeos/farmacologia , Acetilação , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Células HT29 , Humanos , Mucosa Intestinal/citologia , MetilaçãoRESUMO
Staphylococcus aureus is a microorganism capable of causing numerous diseases of the human skin. The incidence of S. aureus skin infections reflects the conflict between the host skin's immune defenses and the S. aureus' virulence elements. Antimicrobial peptides (AMPs) are small protein molecules involved in numerous biological activities, playing a very important role in the innate immunity. They constitute the defense of the host's skin, which prevents harmful microorganisms from entering the epithelial barrier, including S. aureus. However, S. aureus uses ambiguous mechanisms against host defenses by promoting colonization and skin infections. Our review aims to provide a reference collection on host-pathogen interactions in skin disorders, including S. aureus infections and its resistance to methicillin (MRSA). In addition to these, we discuss the involvement of defensins and other innate immunity mediators (i.e., toll receptors, interleukin-1, and interleukin-17), involved in the defense of the host against the skin disorders caused by S. aureus, and then focus on the evasion mechanisms developed by the pathogenic microorganism under analysis. This review provides the "state of the art" on molecular mechanisms underlying S. aureus skin infection and the pharmacological potential of AMPs as a new therapeutic strategy, in order to define alternative directions in the fight against cutaneous disease.