Molecular transduction in receptor-ligand systems by planar electromagnetic fields / Transdução molecular em sistemas receptor-ligante por campos electromagnéticos planares

The coupling of a ligand with a molecular receptor induces a signal that travels through the receptor, reaching the internal domain and triggering a response cascade. In previous work on T-cell receptors and their coupling with foreign antigens, we observed the presence of planar molecular patterns able to generate electromagnetic fields within the proteins. These planes showed a coherent (synchronized) behavior, replicating immediately in the intracellular domain that which occurred in the extracellular domain as the ligand was coupled. In the present study, we examined this molecular transduction - the capacity of the coupling signal to penetrate deep inside the receptor molecule and induce a response. We verified the presence of synchronized behavior in diverse receptor ligand systems. To appreciate this diversity, we present four biochemically different systems - TCR-peptide, calcium pump-ADP, haemoglobin-oxygen, and gp120-CD4 viral coupling. The confirmation of synchronized molecular transduction in each of these systems suggests that the proposed mechanism would occur in all biochemical receptor-ligand systems.

A ligação de um ligante com um receptor molecular induz um sinal que viaja através do receptor, chegando ao domínio interno e disparando uma cascata de resposta. Em trabalhos anteriores em receptores de células T e sua ligação com antígenos estranhos, observamos a presença de padrões moleculares planares capazes de gerar campos eletromagnéticos dentro das proteínas. Esses planos mostraram um comportamento coerente (sincronizado), replicando, instantaneamente, no domínio intracelular o que ocorreu no domínio extracelular, enquanto o ligante era acoplado. No presente estudo, examinamos essa transdução – a capacidade de um sinal de acoplamento de penetrar profundamente a molécula receptora e induzir uma resposta. Verificamos a presença de um comportamento coerente em sistemas diversos de receptor-ligante. Para apreciar essa diversidade, apresentamos quatro sistemas bioquímicos diferentes: TCR-peptídeo, ADP-bomba de cálcio, hemoglobina-oxigênio e gp120-CD4 acoplamento viral. A confirmação de transdução molecular sincronizada em cada um desses sistemas sugere que o mecanismo proposto ocorreria em todos os sistemas bioquímicos receptor-ligante.

Molecular transduction in receptor-ligand systems by planar electromagnetic fields

Abstract The coupling of a ligand with a molecular receptor induces a signal that travels through the receptor, reaching the internal domain and triggering a response cascade. In previous work on T-cell receptors and their coupling with foreign antigens, we observed the presence of planar molecular patterns able to generate electromagnetic fields within the proteins. These planes showed a coherent (synchronized) behavior, replicating immediately in the intracellular domain that which occurred in the extracellular domain as the ligand was coupled. In the present study, we examined this molecular transduction - the capacity of the coupling signal to penetrate deep inside the receptor molecule and induce a response. We verified the presence of synchronized behavior in diverse receptor-ligand systems. To appreciate this diversity, we present four biochemically different systems - TCR-peptide, calcium pump-ADP, haemoglobin-oxygen, and gp120-CD4 viral coupling. The confirmation of synchronized molecular transduction in each of these systems suggests that the proposed mechanism would occur in all biochemical receptor-ligand systems.

Resumo A ligação de um ligante com um receptor molecular induz um sinal que viaja através do receptor, chegando ao domínio interno e disparando uma cascata de resposta. Em trabalhos anteriores em receptores de células T e sua ligação com antígenos estranhos, observamos a presença de padrões moleculares planares capazes de gerar campos eletromagnéticos dentro das proteínas. Esses planos mostraram um comportamento coerente (sincronizado), replicando, instantaneamente, no domínio intracelular o que ocorreu no domínio extracelular, enquanto o ligante era acoplado. No presente estudo, examinamos essa transdução a capacidade de um sinal de acoplamento de penetrar profundamente a molécula receptora e induzir uma resposta. Verificamos a presença de um comportamento coerente em sistemas diversos de receptor-ligante. Para apreciar essa diversidade, apresentamos quatro sistemas bioquímicos diferentes: TCR-peptídeo, ADP-bomba de cálcio, hemoglobina-oxigênio e gp120-CD4 acoplamento viral. A confirmação de transdução molecular sincronizada em cada um desses sistemas sugere que o mecanismo proposto ocorreria em todos os sistemas bioquímicos receptor-ligante.

Molecular transduction in receptor-ligand systems by planar electromagnetic fields / Transdução molecular em sistemas receptor-ligante por campos electromagnéticos planares

The coupling of a ligand with a molecular receptor induces a signal that travels through the receptor, reaching the internal domain and triggering a response cascade. In previous work on T-cell receptors and their coupling with foreign antigens, we observed the presence of planar molecular patterns able to generate electromagnetic fields within the proteins. These planes showed a coherent (synchronized) behavior, replicating immediately in the intracellular domain that which occurred in the extracellular domain as the ligand was coupled. In the present study, we examined this molecular transduction - the capacity of the coupling signal to penetrate deep inside the receptor molecule and induce a response. We verified the presence of synchronized behavior in diverse receptorligand systems. To appreciate this diversity, we present four biochemically different systems - TCR-peptide, calcium pump-ADP, haemoglobin-oxygen, and gp120-CD4 viral coupling. The confirmation of synchronized molecular transduction in each of these systems suggests that the proposed mechanism would occur in all biochemical receptor-ligand systems.

A ligação de um ligante com um receptor molecular induz um sinal que viaja através do receptor, chegando ao domínio interno e disparando uma cascata de resposta. Em trabalhos anteriores em receptores de células T e sua ligação com antígenos estranhos, observamos a presença de padrões moleculares planares capazes de gerar campos eletromagnéticos dentro das proteínas. Esses planos mostraram um comportamento coerente (sincronizado), replicando, instantaneamente, no domínio intracelular o que ocorreu no domínio extracelular, enquanto o ligante era acoplado. No presente estudo, examinamos essa transdução ­ a capacidade de um sinal de acoplamento de penetrar profundamente a molécula receptora e induzir uma resposta. Verificamos a presença de um comportamento coerente em sistemas diversos de receptor-ligante. Para apreciar essa diversidade, apresentamos quatro sistemas bioquímicos diferentes: TCR-peptídeo, ADP-bomba de cálcio, hemoglobina-oxigênio e gp120-CD4 acoplamento viral. A confirmação de transdução molecular sincronizada em cada um desses sistemas sugere que o mecanismo proposto ocorreria em todos os sistemas bioquímicos receptor-ligante.

Research progress of effect of berberine in treatment of ulcerative colitis based on cell signaling pathway / 中国中药杂志

Berberine is the main extract of Coptis chinensis, and its anti-inflammatory, antioxidant, antibacterial and immunomodulatory effects have been confirmed by modern studies. Ulcerative colitis(UC) is a chronic, idiopathic inflammatory bowel disease with unknown etiology. Its causes involve genetics, intestinal microecology and mucosal immune system disorders. In this paper, literatures on relevant pathways and mechanism of berberine on ulcerative colitis in recent years were consulted and summarized to provide me-thods and ideas for developing berberine in the treatment of UC and exploring the mechanisms. The results showed that berberine protects the intestinal mucosal barrier, restores the body's normal immune response, and improves oxidative stress by regulating multiple signaling pathways, such as JAK-STAT, NK-κB, PI3 K-AKT, MAPK, Nrf2, ERS, and MLCK-MLC, so as to treat UC.

Glycogen synthase kinase 3ß participates in late stages of Dengue virus-2 infection

BACKGROUND Viruses can modulate intracellular signalling pathways to complete their infectious cycle. Among these, the PI3K/Akt pathway allows prolonged survival of infected cells that favours viral replication. GSK3β, a protein kinase downstream of PI3K/Akt, gets inactivated upon activation of the PI3K/Akt pathway, and its association with viral infections has been recently established. In this study, the role of GSK3β during Dengue virus-2 (DENV-2) infection was investigated. METHODS GSK3β participation in the DENV-2 replication process was evaluated with pharmacological and genetic inhibition during early [0-12 h post-infection (hpi)], late (12-24 hpi), and 24 hpi in Huh7 and Vero cells. We assessed the viral and cellular processes by calculating the viral titre in the supernatants, In-Cell Western, western blotting and fluorescence microscopy. RESULTS Phosphorylation of GSK3β-Ser9 was observed at the early stages of infection; neither did treatment with small molecule inhibitors nor pre-treatment prior to viral infection of GSK3β reduce viral titres of the supernatant at these time points. However, a decrease in viral titres was observed in cells infected and treated with the inhibitors much later during viral infection. Consistently, the infected cells at this stage displayed plasma membrane damage. Nonetheless, these effects were not elicited with the use of genetic inhibitors of GSK3β. CONCLUSIONS The results suggest that GSK3β participates at the late stages of the DENV replication cycle, where viral activation may promote apoptosis and release of viral particles.

Anti-lung Cancer Mechanism of Qingzao Jiufei Tang / 中国实验方剂学杂志

Lung cancer is currently the leading malignant tumor in China, which seriously endangers people's health. Nowadays, traditional Chinese medicine (TCM) has played an increasingly important role in the comprehensive treatment of lung cancer. It has unique advantages in promoting postoperative recovery, reducing the side effects of radiotherapy and chemotherapy, and effectively prolonging the lifetime of patients. Qingzao Jiufei Tang is mainly used to treat the syndrome of Qi-Yin deficiency due to dryness-heat injury to the lungs. The experimental and clinical studies have confirmed that Qingzao Jiufei Tang has a good anti-lung cancer effect and broad application prospects. In this paper, we reviewed relevant literatures through China National Knowledge Infrastructure (CNKI), Weipu Data, Wanfang Data, PubMed and other databases in recent years, and found a few reports on the anti-lung cancer effect of Qingzao Jiufei Tang. There was still a lack of systematic and comprehensive explanation for its specific mechanism of action against lung cancer. This paper systematically summarized the clinical application of Qingzao Jiufei Tang against lung cancer in recent years, as well as its effects through cell-related signaling pathways and energy metabolism against lung cancer cells. It is clear that this decoction can significantly inhibit the signaling pathways of epithelial growth factor receptor (EGFR), nuclear transcription factor kappa B (NF-κB)/intercellular cell adhesion molecule-1 (ICAM-1), and Janus kinase 2 (JAK2)/signal transducers and activators of transcription 3 (STAT3) of the lung cells. It could also inhibit energy metabolism of tumor cells, and reduce the production of relevant metabolites. This will provide new ideas for the clinical application of Qingzao Jiufei Tang against lung cancer.

Sinalização e metabolismo celulares durante a diferenciação de linfócitos B humanos em secretores de anticorpos na presença do vírus da Dengue in vitro e em pacientes com Dengue / B cell signaling and metabolism during antibody-secreting cell differentiation in the presence of Dengue virus in vitro and in Dengue patients

A Dengue é uma doença viral sistêmica, transmitida por mosquitos, que afeta anualmente cerca de 100 milhões de pessoas em todo o mundo. Causada por quatro sorotipos do vírus da Dengue (DENV), suas manifestações clínicas podem variar de assintomáticas à formas que podem levar a óbito. Curiosamente, os pacientes com Dengue apresentam uma resposta exacerbada das células secretoras de anticorpos (ASCs) no sangue cerca de sete dias após o início dos sintomas. A frequência dessas ASCs induzidas pelo DENV representa mais de 50% de todas as células B circulantes no sangue. Essa quantificação é maior que aquelas encontradas em outras infecções virais, contextos de imunização e até mesmo em pacientes com neoplasias de ASCs. Além disso, a magnitude dessa resposta transitória se correlaciona com a gravidade da doença. Então, como a infecção pelo DENV induz essa resposta enorme? Para responder à essa pergunta, combinamos abordagens in vitro e in silico. Células mononucleares do sangue periférico (PBMCs) obtidas de indivíduos saudáveis foram cultivadas in vitro durante sete dias na presença do DENV ou mitógenos. Após a estimulação pelo DENV, as células B presentes nas PBMCs foram capazes de se diferenciarem em ASCs, tanto fenotipicamente quanto funcionalmente, em magnitude similar àquelas estimuladas com mitógenos. Essa diferenciação demonstrou ser dependente da presença de outras células contidas nas PBMCs, assim como do contato célula-célula. Embora ambos os estímulos tenham sido capazes de induzir a diferenciação de ASCs, eles diferiram metabolicamente e transcricionalmente. PBMCs estimuladas pelo DENV apresentaram um maior consumo de triptofano, associado à maior expressão de IDO1 e IDO2 e maior síntese de quinurenina, bem como maiores expressões de IL-10, BAFF e SYK. Ainda, as concentrações de quinurenina foram positivamente correlacionadas com a enumeração de ASCs nessas culturas. Dados de transcriptoma públicos de pacientes com Dengue também suportam esses achados. Outros flavivírus, como o vírus Zika e a cepa vacinal da Febre Amarela não foram capazes de induzir a mesma magnitude de diferenciação das células B em ASCs in vitro. Tão pouco apresentaram correlação entre a enumeração de ASCs e a síntese de quinurenina. Por fim, através da construção de uma hipotética via de diferenciação de células B em ASCs durante infecção pelo DENV, através da combinação de dados da literatura e transcriptomas públicos, demonstramos que moléculas relacionadas à via do STAT3 (IL-10, IL-6, IRF4 e BLIMP1) estão mais expressas nos pacientes infectados e moléculas que respondem aos sinais de cálcio (Calcineurina, NFATC1, DOK3 e GRB2) estão menos expressas nos pacientes infectados. Esses dados proporcionam um melhor entendimento da resposta de células B durante a infeção pelo DENV, particularmente sobre como o metabolismo e a sinalização das células B estão conectados nesse processo

Dengue is a mosquito-borne viral disease that affects annually about 100 million people worldwide. Caused by four Dengue virus (DENV) serotypes, it ranges from asymptomatic to life threatening forms. Curiously, Dengue patients present an exacerbated blood antibody-secreting cell (ASCs) response around seven days after the symptoms onset. The frequency of those DENV-induced ASCs represents more than 50% of all circulating blood B cells. This is greater than found in others viral infections, immunization contexts and even in ASCs related-leukemia patients. Moreover, the magnitude of that transitory response correlates with the disease severity. So, how does the DENV infection induce this enormous response? In order to answer this question we have combined in vitro and in silico approaches. Peripheral blood mononuclear cells (PBMC) obtained from healthy individuals were cultured in vitro during seven days in the presence of DENV or mitogens. Upon the DENV stimulation, PBMC-contained B cells were able to differentiate phenotypically and functionally into ASCs, both phenotypically and functionally, in a similar magnitude than mitogen-stimulated cells. This differentiation was demonstrated to be dependent of the presence of the remaining PBMCs, as well as of the cell-cell contact. Although both stimuli were able to induce the ASCs differentiation, they differed metabolically and transcriptionally. DENV-stimulated PBMCs showed higher tryptophan consumption, associated with higher IDO1 and IDO2 expression and higher kynurenine synthesis, as well as higher IL-10, BAFF and SYK expressions compared to mitogen-exposed counterparts. Additionally, the kynurenine concentrations were positively correlated with the ASCs-enumeration in those cultures. Public transcriptome data supports these findings as well. Other flaviviruses, such as Zika virus and the attenuated vaccine Yellow Fever were not able to induce the same magnitude of ASCs differentiation in vitro. Hence, they did not present a correlation between the number of generated ASCs and the supernatant kynurenine levels. Based on the combination of the literature and public transcriptome data, we have constructed a hypothetical B cell differentiation pathway that might be occurring during DENV infection. It displays that STAT3 pathway-related molecules (IL-10, IL-6, IRF4 and BLIMP1) are more expressed in Dengue patients and molecules that respond to calcium signals (Calcineurin, NFATC1, DOK3 and GRB2) are less expressed in Dengue patients than in control. These data provide a better understanding of the B cell response elicited by DENV infection, particularly about how the B cell metabolism and signaling can be connected into this process

Immunohistochemical expression of polo-like kinase 1 in oral squamous cell carcinoma and oral submucous fibrosis

Polo-like kinase 1 (PLK1) is a critical molecule in the proliferation of several human cancers. Overexpression of PLK1 has been correlated with cancer cell proliferation and lower overall survival rates. Although PLK1 has been studied in various tumors, information regarding its expression in oral cancer and precancer is limited. Aims: This study is aimed at evaluating the expression of PLK1 in a potentially malignant and malignant disorder of the oral cavity, namely, oral submucous fibrosis (OSMF) and oral squamous cell carcinoma (OSCC), respectively, using the immunohistochemistry technique. It also intended to evaluate the association of the various histological grades of OSCC with the intensity of PLK1 expression. Subjects and Methods: Thirty OSMF, thirty OSCC tissues, and thirty control tissues were obtained, and the expression of PLK1 was detected by immunohistochemistry using rabbit antihuman PLK1 polyclonal antibodies (Abcam Ab47867). The association between staining intensity and histological grade of OSCC was evaluated. Statistical Analysis Used: Using SPSS 20 version, a test for proportions, nonparametric Chi-square/correlation analysis was used to compare differences in proportions of categorical variables of interest between groups. Results: PLK1 was positively expressed in 27 (90%) OSCC tissues. OSMF showed no detectable staining in 27 (90%) tissues and positive staining in 3 (10%) tissues. PLK1 showed no staining (0%) in normal tissues. Statistically significant associations were not found between staining intensity and histological grade of OSCC. Conclusions: PLK1 could be a promising progression marker for OSCC. Therapeutically, targeting PLK1 may be a new approach to fight oral cancer.

Understanding the biology of HER3 receptor as a therapeutic target in human cancer

HER3 belongs to the human epidermal growth factor receptor (HER) family which also includes HER1/EGFR/erbB1, HER2/erbB2, and HER4/erbB4. As a unique member of the HER family, HER3 lacks or has little intrinsic tyrosine kinase activity. It frequently co-expresses and forms heterodimers with other receptor tyrosine kinases (RTKs) in cancer cells to activate oncogenic signaling, especially the PI-3K/Akt pathway and Src kinase. Elevated expression of HER3 has been observed in a wide variety of human cancers and associates with a worse survival in cancer patients with solid tumors. Studies on the underlying mechanism implicate HER3 expression as a major cause of treatment failure in cancer therapy. Activation of HER3 signaling has also been shown to promote cancer metastasis. These data strongly support the notion that therapeutic inactivation of HER3 and/or its downstream signaling is required to overcome treatment resistance and improve the outcomes of cancer patients.

Functions and characteristics of calcium-sensing receptorsand effects of CaSR on characteristics of adult stem cells / 中国药理学通报

Calcium-sensing receptor(CaSR) is a widely distributed G-protein coupled receptor.The activated CaSR plays an important role in many kinds of signaling pathway regulation, such as Ca2+ signaling pathway.It not only maintains the body calcium balance, but also is involved in the regulation of a variety of cell secretion, proliferation, apoptosis, and ion channel opening processes.CaSR expression is involved in stem cell migration, adhesion and homing in hematopoietic stem cells and mesenchymal stem cells.The activated CaSR also regulated the function of itself and characteristics in stem cells through a variety of cell signaling pathways.We introduce the functions and characteristics of CaSR, the relationship between CaSR and disease, and review the effects of the biological characteristics on hematopoietic stem cells and mesenchymal stem cells.

Detection and significance of cytokines related to NF-κB signaling pathway in patients with different TCM syndrome types of diabetic nephropathy / 重庆医学

Objective To explore the expression difference of cytokines related to nuclear factor kappa B (NF-κB) signaling pathway among different traditional Chinese medicine (TCM) syndromes in the patients with diabetic nephropathy (DN).Methods Serum tumor necrosis factor-α (TNF-α),interleukin-1 (IL-1),interleukin-6 (IL-6) and interleukin-8 (IL-8) in 146 patients with DN and 62 individuals undergoing healthy physical examination in the control group were measured.Results The levels of serum TNF-α,IL-1,IL-6 and IL-8 in various DN groups were significantly higher than those in the control group (P＜0.05).The levels of serum TNF-α,IL-1,IL-6 and IL-8 were significantly different among groups of different TCM syndromes (P＜0.05).With the progression of DN,all cytokines levels showed a gradually increasing trend,moreover the increased extents and time were different in different TCM syndrome types of DN.Conclusion The levels of serum TNF-α,IL-1,IL-6 and IL-8 related to NF-κB signaling pathway are correlated with different TCM syndromes types and may play a role in the occurrence and progression of different TCM syndrome types of DN.

The therapeutic effect and its mechanism of dendritic cells overexpressed suppressors of cytokine signaling 1 on acute liver failure in mice / 中华传染病杂志

Objective To investigate the impact of suppressor of cytokine signaling 1 (SOCS1) overexpression on dendritic cells (DC) functions and its therapeutic effect on acute liver failure (ALF) in mice.Methods Bone marrow derived dendritic cells (BMDC) from C57BL/6 mice were transfected with lentivirus encoding SOCS1 and negative control lentivirus at a MOI=50, and labeled as DC-SOCS1and DC-VNG, respectively after 96 hours of successful transduction.Then DCs were stimulated with lipopolysaccharides(LPS)1 mg/L and collected for flow cytometry analysis of surface costimulatory molecules, allogeneic mixed lymphocyte reaction (MLR) and western blot test of Janus kinase (JAK)/signaling transducers and activators of transcription (STAT) pathway.Afterwards, 90 mice were randomly assigned into 4 groups including 12 in normal control group, 26 in ALF group, 26 in treatment groups with DC-SOCS1 and 26 with the treatment of DC-VNG.All were received tail vein injection with normal saline, modified DC-VNG and DC-SOCS1 suspended in normal saline, respectively.Twelve hours after injection, LPS (10 μg/kg)/D-GaIN (600 mg/kg) were injected intraperitoneally to induce ALF model.The mortality, serum levels of alanine aminotransferase (ALT) and aspartate transaminase (AST), liver pathology and proportion of splenic regulatory T cells of each group were observed.Means in different groups were compared with one-way ANOVA analysis.Categorical variables were analyzed with x2 test.Variables were examined with normality test and homogeneity of variance with LSD test.Results The results of mixed lymphocyte reaction (MLR) revealed that T cell proliferation ratio in DC-SOCS1 group with mixture ratio of 100∶1 were (25.87±0.38)%, which was lower than that of mixture ratio of 10∶1 in the mDC group ([84.29±3.25]%) with statistical significance (x2=49.821, P<0.01);interleukin (IL)-10 concentration was higher than that in mDC group with mixture ratio of 10∶1 with statistical significance (F=20.112, P<0.05);IL-6 concentration was also lower with statistical significance (F=47.718, P<0.05).Compared to imDC, expression of JAK2 (t=0.525,0.523 and 0.489, respectively, all P<0.01), signal transduction factors and activation of transcription factors-1 (STAT1) (t=0.442,0.400 and 0.402, respectively, all P<0.01) and SOCS1 (t=0.322,0.363 and 1.090, respectively, all P<0.01) of mDC, DC-VNG and DC-SOCS1 after LPS stimulation increased significantly.Furthermore, the expressions of phosphorylated STAT1 (p-STAT1) and phosphorylated JAK2 (p-JAK2) of DC-SOCS1 were much lower than those of the mDC, with statistically significant difference (t=-3.840 and 0.254, respectively, both P<0.01).Pathological analysis revealed that there existed moderate hepatic cells necrosis and less immune cell infiltration in DC-SOCS1 group accompanied with higher regulatory T lymphocytes proportion than those in ALF group and DC-VNG group.Survival rate of ALF with DC-SOCS1 treatment group was significantly higher than that of ALF group with statistical difference (x2=12.87, P<0.05).Conclusions DC-SOCS1could sustain an immature state and exhibit as regulatory DC through negative regulation of JAK2/STAT1 pathway with overexpression of SOCS1.Infusion of DC-SOCS1 could ameliorate ALF by inhibiting aggressive inflammation response with increased proportion of regulatory T cells in mice, which shows good therapeutic effect for ALF mice.

Relationship between inflammatory cytokines of IL-1β and TNF-α and intervertebral disc degeneration / 中国骨伤

The inflammatory cytokines of IL-1β and TNF-α participate in the process of intervertebral disc degeneration is focused by the spine surgeons. Inflammatory cytokines represented by IL-1β and TNF-α act as the key factors in the process of intervertebral disc degeneration resulting in low back pain and radicular symptoms. Annulus fibrosus and nucleus pulposus can secrete TNF-α and IL-1β under the stimulation of mechanical injury, overstressed, genetic susceptibility and infection. The mechanism of inflammatory cytokines in intervertebral disc degeneration needs further investigation. The emphasis of researches will be on the inflammatory cytokines in the regulation of mechanism in the intervertebral disc degeneration, molecular targeted therapy, cell signaling pathways and the best time of anti-inflammatory therapy providing more evidence in the clinical application.

Cell signaling pathways and bronchopulmonary dysplasia / 国际儿科学杂志

The bronchopulmonary dysplasia(BPD),one of the most common complications in prema-ture infants,has become one of the most difficult problems in neonatal intensive care unit. The molecular mecha-nism of BPD is extremely complicated,of which the pathogenesis process requires the participation of many sig-nal transduction pathways. This article summarizes the probable relationship of mitogen activated protein kinases signal pathways,nuclear factor-κB pathways,transforming growth factor beta pathways,Wnt pathways,mTOR pathways with BPD.

Advance of microenvironment and the pathogenesis of hepatocellular carcinoma (HCC) / 基础医学与临床

Hepatocellular carcinoma ( HCC) is a prevalent primary liver cancer that is driven by cumulative chan-ges in the hepatocyte genome which were influenced by the liver microenvironment .The tumor microenvironment is a dynamic system, including cancer cells, stroma, the extracellular matrix.tissue hypoxia, diet, gastrointestinal tract ( GIT) microflora and circulating microvesicles , The liver microenvironment plays a pivotal role in HCC tu-merigenesis , progression and therapeutic efficienry .The study of the HCC microenvironment will provide new in-sights into the mechanism of tumourigenesis and potential novel targets in the treatment of HCC .

Comprehensive Roles of TP53 in Cell Signaling, Apoptosis and Carcinogenesis – A Review.

TP53 gene is a tumor suppressor gene and it inhibits the emergence of cancerous growth. The signaling of TP53 takes part in the co-ordination of cellular response to various kinds of stress like hypoxia and DNA damage. The downstream signals start to multiple processes such as MTOR (mechanistic target of rapamycin), apoptosis, and the arrest of cell cycle. TP53 becomes inactivated when encounters tumor growth. According to estimation, more than half of all cancers imply the inactivating mutations of TP53, which leads to the expression of mutant p53 protein. An extensive range of cancers carry the mutations of TP53 or certain other defects which deregulate p53 and its cofactors, making this gene a significant and highly studied tumor suppressor gene. Most of the mutations that are found in human cancers are not inherited but are acquired. As p53 protein binds DNA, it triggers another gene to synthesize a protein named p21 inside the cell, which interferes with a cell division-stimulating kinase (cdk2). When p21 forms a complex with cdk2 the cell cannot pass onto the next phase of cell division. Therefore, Mutant p53 can no longer get itself attached to DNA effectively, and as a result, the p21 protein is not made available to function as the 'stop signal' for the division of cell.

O papel de RhoA e Rac1 GTPases nas respostas celulares após danos no DNA induzidos por radiação ionizante gama / The role of RhoA and Rac1 GTPases in cellular responses after DNA damage induced by ionizing gamma radiation

O mecanismo pelo qual uma célula responde a algum dano no seu material genético é extremamente importante. Isto ocorre pela rápida ativação da maquinaria de reparo de danos no DNA, a qual é composta por uma rede intrincada de sinalização proteica, culminando no reparo do DNA; porém se o dano for irreparável ocorre ativação de mecanismos de morte celular. RhoA,e Rac1 pertencem a família das pequenas proteínas sinalizadoras Rho GTPases, as quais atuam como interruptores moleculares ciclando entre estado ativo (ligada a GTP) e inativo (ligada a GDP). Os componentes desta família estão relacionados ao controle dos mais diversos processos celulares como, por exemplo, remodelamento do citoesqueleto, migração, adesão, endocitose, progressão do ciclo celular e oncogênese. No entanto, apesar das proteínas Rho GTPases estarem envolvidas em um amplo espectro de atividades biológicas, há poucas informações sobre seu papel na manutenção da integridade genômica quando células são submetidas a algum agente genotóxico. Para investigar o envolvimento das GTPases RhoA e Rac1 nas respostas de células submetidas a radiação gama, foram gerados, a partir de células de carcinoma de cervix humano - HeLa, sublinhagens clonais mutantes de RhoA e Rac1 expressando exogenamente RhoA constitutivamente ativa (HeLa-RhoA V14), RhoA dominante negativa (HeLa-RhoA N19), Rac1 constitutivamente ativa (HeLa-Rac1 V12) e Rac1 dominante negativa (HeLa-Rac N17). Após estas linhagens celulares serem expostas a diferentes doses de radiação gama, observamos que ambas GTPases, RhoA e Rac1, são ativadas em resposta aos efeitos da radiação. Além disso, a modulação da atividade destas enzimas, através das mutações, levou a uma alteração das respostas celulares frente aos danos no DNA, como uma redução da capacidade de reparar quebras simples e duplas nas fitas do DNA. Por outro lado, a deficiência de RhoA ou Rac1 GTPase levou a uma redução da ativação de Chk1 e Chk2 ou da fosforilação da histona H2AX, respectivamente, prejudicando os mecanismos de detecção de danos no DNA e levando as células a permanecerem mais tempo nos pontos de checagem G1/S e/ou G2/M do ciclo celular. Esses fatores contribuíram de modo expressivo para a redução da proliferação e sobrevivência celular levando as células à morte. Por fim, ensaios celulares de reparo de danos de um DNA exógeno através de mecanismos de Recombinação Homóloga (HR) e Recombinação Não-Homóloga de extremidades (NHEJ), demonstraram que a inibição da atividade de RhoA reduz significativamente a eficiência de ambas vias de reparo. Desta maneira, este trabalho demonstra e reforça a existência de mais um viés de atuação das pequenas GTPases RhoA e Rac1, agora em células HeLa, nas respostas celulares aos danos induzidos por exposição a radiação gama, modulando a sobrevivência, proliferação e indiretamente modulando resposta ao reparo do DNA através da via de Recombinação Homóloga e Não-Homóloga

The mechanism by which a cell responds to DNA damage is extremely important. This occurs by a quick activation of the DNA damage repair machinery, which consists of an intricate protein signaling network culminating in DNA repair. But if the damages are irreparable occurs there is activation of cell death mechanisms. RhoA and Rac1 belong to family of small Rho GTPases, signaling proteins that act as molecular switches cycling between the active state (GTP-bound) and inactive state (GDP-bound). Members of this family are implicated in the control of diverse cellular process such as cytoskeletal remodeling, migration, adhesion, endocytosis, cell cycle progression, and oncogenesis. However, despite Rho proteins are involved in a broad spectrum of biological activities, there is just a few information about their roles in the maintenance of genomic integrity, that is, when the cells are subjected to some kinf of genotoxic agent. To investigate the involvement of the GTPases RhoA and Rac1 in cellular responses to gamma radiation, we generated from human cervix carcinoma cells - HeLa, clonal sublines of RhoA and Rac1 mutants, exogenous and stably expressing the constitutively active RhoA (HeLa-RhoA V14), the dominant negative RhoA (HeLa-RhoA N19), the constitutively active Rac1 (HeLa-Rac1 V12) and the dominant negative Rac1 (HeLa-Rac1 N17). After all these cell lines have been exposed to different doses of gamma radiation, we found that both GTPases, RhoA and Rac1, are activated in response to the radiation effects. Furthermore, the modulation of two enzymes activity, by using the mutant clones, led to a change in cellular responses to the DNA damage, as the reduction in the capacity of repairing DNA single and double strand breaksr. On the other hand, the deficiency of RhoA or Rac1 GTPase led to a reduction of Chk1 and Chk2 activation, or on the phosphorylation of histone H2AX, respectively, hindering the mechanisms of DNA damage detection and arresting cells in the G1/S and/or G2/M checkpoints of cell cycle. These factors significantly contributed to the reduction of cell proliferation and survival, leading cells to death. Finally, cellular assays of DNA damage repair of exogenous DNA by Homologous Recombination (HR) and Non-Homologous End Joining (NHEJ), demonstrated that RhoA inhibition significantly reduced the repair efficiency of both pathways. Thus, this work demonstrates and reinforces the existence of other biological functions of small GTPases RhoA and Rac1 in HeLa cells, by regulating cellular responses to DNA damage induced by exposure to gamma radiation, modulating the survival, proliferation and indirectly modulating the response to DNA damage repair pathway through the Homologous Recombination and Non-Homologous Recombination

Papel de los receptores tipo toll (TLRs) y receptores para dominios de oligomerización para la unión a nucleótidos (NLRs) en las infecciones virales / Role of toll-like receptors (TLRs) and nucleotide-binding oligomerization domain receptors (NLRs) in viral infections

Las células del sistema inmunitario (SI) son capaces de reconocer una gran variedad de microorganismos, a través de los receptores que se encuentran expresados y distribuidos a lo largo de su arquitectura celular. La interacción entre los patrones moleculares asociados a microorganismos o a daño (PMAM o PMAD) y los receptores reconocedores de patrones (RRP) presentes en las células del hospedero es un evento crítico que implica procesos intracelulares de señalización que finalizan en la expresión de mediadores tanto proinflamatorios como antivirales. Por consiguiente, de la integridad de estos receptores dependerá el buen funcionamiento de los distintos mecanismos de transducción de señal desde las membranas celulares al citoplasma y por ende, de la respuesta que el SI desencadene contra los patógenos entre ellos los agentes virales. De allí que, en esta revisión se discutirá el papel de los receptores tipo toll (TLRs) y receptores para dominios de oligomerización para la unión a nucleótidos (NLRs) en las infecciones virales, tomando como evidencia los estudios en humanos y ratones que a la fecha se conocen.

The immune system (IS) cells are capable of recognizing a wide variety of microorganisms, through receptors that are expressed and distributed throughout the cell architecture. The interaction between the pathogen-associated molecular patterns or damage-associated molecular patterns (PAMPs or DAMPs) and pattern recognition receptors (PRR), present in host cells, is a critical event that involves intracellular signaling processes that end up in the expression of both, proinflammatory and antiviral mediators. Accordingly, the proper functioning of the different mechanisms of signal transduction from the cell membrane to the cytoplasm will depend on the integrity of these receptors (PRR); and therefore, the IS response triggered against pathogens including viral agents. Hence, in this review we discuss the role of toll-like receptors (TLRs) and nucleotide-binding oligomerization domain receptors (NLRs) in viral infections, using as evidence the studies in humans and mice known to date.

Protective effect of thymosin β4 on severe acute pancreatitis in rats / 中华急诊医学杂志

Objective To investigate the protective effects and mechanisms of intraperitoneal administration of thymosin β4 on severe acute pancreatitis in rats.Methods Fifty-four male Sprague-Dawley rats were randomly (random number) divided into sham operation (SO) group,severe acute pancreatitis (SAP) group and thymosin β4 (Tβ4) pretreatment group (n =18 in each group).SAP rat model was prepared by retrograde injection of 5％ sodium taurocholate into the biliopancreatic duct.Rats in Tβ4 group were treated with thymosin β4 (6 mg/kg) by intraperitoneal administration prior to SAP modeling.Six rats in each group were sacrificed at 3,6,12 hours,respectively after modeling.The serum levels of amylase,tumor necrosis factor-α (TNF-α),interleukin-1 β (IL-1 β),and interleukin-6 (IL-6)were detected,and pathological scores of the tissue of pancreas head were evaluated under light microscope.Pancreatic nuclear factor-kappa 1B (NF-κB) p65 and IκB α levels were detected by the Western blot.All data were analyzed by using the analysis of variauce or t test.Results The levels of serum amylase of SAP 3,6 and 12 hours groups were (3221 ±394) U/L,(4509 ±474) U/L and (6280 ±728) U/L,which were significantly higher than (2598±416) U/L,(3639 ±373) U/L and (4782 ±466) U/L of the Tβ4 groups (t =-2.666,-3.530,-4.245,P ＜ 0.05).The levels of serum TNF-α of the SAP 3,6 and 12 hours groups were (247.7 ± 18.5) pg/mL,(313.5 ± 17.7) pg/mL and (359.3 ±22.6) pg/mL,which were higher than (182.3 ± 13.6) pg/mL,(258.9 ± 14.9) pg/mL and (278.1 ± 16.3) pg/mL of the Tβ4 groups (t =-6.964,-5.769,-7.152,P ＜ 0.05).The levels of serum IL-1 β of the SAP 3,6 and 12 hours groups were (258.2±10.5) pg/mL,(345.1 ±22.0) pg/mL and (430.9 ±25.4) pg/mL,which were higher than (170.3 ± 12.4) pg/mL,(263.5 ± 13.3) pg/mL and (303.7 ± 16.1) pg/mL of the Tβ4 groups (t =-13.258,-7.762,-10.355,P ＜ 0.05).The levels of serum IL-6 of SAP 3,6 and 12 hours groups were (266.3 ±11.5) pg/mL,(355.0 ±24.4) pg/mL and (429.2 ±33.7) pg/ mL,which were higher than (171.1 ± 13.0) pg/mL,(234.9 ± 19.2) pg/mL and (277.2 ± 19.2) pg/ mL of the Tβ4 groups (t =-13.401,-9.474,-9.582,P ＜ 0.05).The pancreatic pathological scores of the SAP3,6 and 12 hours groups were (6.25 ±0.94),(8.83 ±0.82) and (12.08 ±1.16),which were higher than (4.17 ± 0.93),(6.33 ± 0.82) and (7.33 ± 1.25) of the Tβ4 groups (t =-3.867,-5.303,-6.823,P ＜ 0.05).The relative expression of pancreatic NF-κB p65 in SO group was (0.95 ±0.11),which was significantly lower than (2.40 ±0.17) of the SAP 12 hours group (t =-17.368,P＜ 0.05).The relative expression of pancreatic NF-κB p65 in Tβ4 group was 1.50 ± 0.10,which was significantly lower than SAP 12 hours group (t =10.917,P ＜0.05).The relative expression of pancreatic IκB α in SO group was (1.93 ±0.11),which was significantly higher than (0.78 ±0.18) of the SAP 12 hours group (t =13.260,P ＜ 0.05).The relative expression of pancreatic IκB α in Tβ4 group was (1.12±0.10),which was significantly higher than SAP 12 hours group (t =-4.112,P ＜ 0.05).Conclusions Thymosin β4 has the protective effect on SAP rat model,and the mechanism may be associated with inhibition of NF-κB signaling pathway and decreased proinflammatory cytokines.

CD36, a scavenger receptor implicated in atherosclerosis

CD36 is a membrane glycoprotein that is present on various types of cells, including monocytes, macrophages, microvascular endothelial cells, adipocytes and platelets. Macrophage CD36 participates in atherosclerotic arterial lesion formation through its interaction with oxidized low-density lipoprotein (oxLDL), which triggers signaling cascades for inflammatory responses. CD36 functions in oxLDL uptake and foam cell formation, which is the initial critical stage of atherosclerosis. In addition, oxLDL via CD36 inhibits macrophage migration, which may be a macrophage-trapping mechanism in atherosclerotic lesions. The role of CD36 was examined in in vitro studies and in vivo experiments, which investigated various functions of CD36 in atherosclerosis and revealed that CD36 deficiency reduces atherosclerotic lesion formation. Platelet CD36 also promotes atherosclerotic inflammatory processes and is involved in thrombus formation after atherosclerotic plaque rupture. Because CD36 is an essential component of atherosclerosis, defining the function of CD36 and its corresponding signaling pathway may lead to a new treatment strategy for atherosclerosis.