Overview on signal transduction cascades regulation roles of garlic and its bioactive constituents

High-throughput technologies in combination with modern exciting advancements in mass spectrometry-based proteomics and data analysis pipelines have empowered comprehensive characterization of disease phenotypes and their mechanistic regulation by dietary agents and bioactive molecules at unprecedented dimensionality and resolution.Extra-ordinary breakthroughs in the field of nutrigenomics have leveraged our understanding altogether to a new level of maturity.Interdisciplinary researchers have extensively analyzed health promoting and pharmacologically significant properties of garlic(Allium sativum).Importantly,garlic and its biologically active chemicals targeted oncogenic signaling cascades.In this mini-review we have attempted to summarize how garlic and its bioactive constituents regulated signal transduction cascades in cell culture studies and tumor-bearing mice.

Camellia sinensis CsMYB4a participates in regulation of stamen growth by interaction with auxin signaling transduction repressor CsAUX/IAA4

Subgroup 4(Sg4)members of the R2R3-MYB are generally known as negative regulators of the phenylpropanoid pathway in plants.Our previous research showed that a R2R3-MYB Sg4 member from Camellia sinensis(CsMYB4a)inhibits expression of some genes in the phenylpropanoid pathway,but its physiological function in the tea plant remained unknown.Here,CsMYB4a was found to be highly expressed in anther and filaments,and participated in regulating filament growth.Transcriptome analysis and exogenous auxin treatment showed that the target of CsMYB4a might be the auxin signal pathway.Auxin/indole-3-acetic acid 4(AUX/IAA4),a repressor in auxin signal transduction,was detected from a yeast two-hybrid screen using CsMYB4a as bait.Gene silencing assays showed that both CsIAA4 and CsMYB4a regulate filament growth.Tobacco plants overexpressing CsIAA4 were insensitive to exogenous a-NAA,consistent with overexpression of CsMYB4a.Protein-protein interaction experiments revealed that CsMYB4a interacts with N-terminal of CsIAA4 to prevent CsIAA4 degradation.Knock out of the endogenous NtIAA4 gene,a CsIAA4 homolog,in tobacco alleviated filament growth inhibition and a-NAA insensitivity in plants overexpressing CsMYB4a.All results strongly suggest that CsMYB4a works synergistically with CsIAA4 and participates in regulation of the auxin pathway in stamen.

Engineered AAV13 variants with enhanced transduction and confined spread

Precise targeting of specific regions within the central nervous system(CNS)is crucial for both scientific research and gene therapy in the context of brain diseases.Adeno-associated virus 13(AAV13)is known for its restricted diffusion range within the CNS,making it an ideal choice for precise labeling and administration within small brain regions.However,AAV13 mediates relatively low expression of target genes.Here,we introduced specifically engineered modifications to the AAV13 capsid protein to enhance its transduction efficiency.We first constructed AAV13-YF by mutating tyrosine to phenylalanine on the surface of the AAV13 capsid.We then inserted the 7m8 peptide,known to enhance cell transduction,into positions 587/588 and 585/586 of the AAV13 capsid,resulting in two distinct variants named AAV13-587-7m8 and AAV13-585-7m8,respectively.We found that AAV13-YF exhibited superior in vitro infectivity in HEK293T cells compared to AAV13,while AAV13-587-7m8 and AAV13-585-7m8 showed enhanced CNS infection capabilities in C57BL/6 mice,with AAV13-587-7m8 infection retaining a limited spread range.These modified AAV13 variants hold promising potential for applications in gene therapy and neuroscience research.

The Antidepressant Mechanism of JiaWeiWenDan Decoction Regulating p38MAPK-ERK5 Signal Transduction Pathway

Objective: To investigate the anti-depression mechanism of JiaWeiWenDan Decoction in regulating p38MAPK-ERK5 signal transduction pathway. Methods: Depression model rats were randomly divided into Blank Control Group, Model Control Group, Chinese Medicine Treatment Group, and Western Medicine Treatment Group (hereinafter referred to as Blank Group, Model Group, Chinese Medicine Group, and Western Medicine Group), with 48 rats in each group. The mice were treated with p38MAPK-ERK5 on the 7th day, 14th day and 21st day, respectively, and the mice were treated for 28 days. The key targets and cytokines in p38MAPK-ERK5 signal transduction pathway were detected. Results: Compared with the Blank Group, the expression of p38MAPKmRNA in the hippocampus of the Model Group was increased. The Chinese Medicine Group and Western Medicine Group could reduce the expression of p38MAPK mRNA (P P P P Conclusion: The anti-inflammatory effect of JiaWeiWenDan Decoction may be related to the regulation of p38MAPK-ERK5 signaling pathway. With the advance of the treatment week, the best effect was obtained when the treatment was started on the 7th day of modeling.

Molecular mechanisms and cellular process in signal transduction pathway related to air pollutants in obstructive lung diseases:A mini-review

Exposure to air pollutants such as PM_(10),PM_(2.5),PM_(0.1),O_(3),CO,NO2,and SO_(2),and biological pollutants are important factors causing the evolution and furtherance of obstructive lung diseases(OLD),including asthma and chronic obstructive pulmonary disease(COPD).Asthma is the most frequent chronic inflammatory airway disease,characterized by breathlessness,wheezing,chest tightness,and cough,together with the presence of exaggerated expiratory airflow fluctuation that varies over time.COPD is a heterogeneous lung condition characterized by chronic respiratory symptoms such as dyspnea,cough,expectoration,and/or exacerbations due to abnormalities of the airways and/or alveoli that cause persistent,often progressive,airflow obstruction.Understanding the molecular mechanisms and cellular processes based on the development of OLD on exposure to air pollutants will provide insights into the solution of pathogenesis,prevention,and treatment of these conditions.The molecular mechanisms and cellular process involved in signal transduction pathway plays a role in the binding of extracellular signaling molecules and ligands to receptors placed on the cell surface or on the inner side cell that trigger inflammation that occurs,especially when something important enters the cell to bring into a cascade response.This binding then alters the cell metabolism,shape,and gene expression in the airway.This review aimed to reveal the effect of air pollutants on the molecular mechanisms and cellular processes involved in the signal transduction pathways in OLD.

Involvement of cAMP in ABA Signal Transduction in Tobacco Suspension Cells

Abscisic acid (ABA) plays an important role in plant growth and developmental processes. Although some ABA signal molecules, such as cADPR, Ca2+, etc., have been reported, there. was no evidence proving the involvement of cAMP in A-B-A, signal transduction. In this present study, the constructed gene ( rd29A-GUS) was transformed into Nicotiana tabacum, and calli was induced from the transgenic plant. The suspension cells obtained from the callus grew well and uniformly. Treatment of the suspension cells with ABA led to an increase in GUS activity, indicating that these transgenic suspension cells are useful for the study of ABA signaling. Addition of nicotinamide (cADPR inhibitor) or U-73122 (phospholiphase C inhibitor) could only partially inhibit the increase of GUS activity elicited by ABA. The inhibitory effect of nicotinamide was enhanced by application of K252a (inhibitor of protein kinase). Treatment of the suspension cells with 8-Br-cAMP, a membrane-permeable analogue of cAMP, could partially replace the effect of ABA. Furthermore, intracellular addition of IBMX (phosphodiesterase inhibitor) mimicked die effect of exogenous cAMP on the deduction of expression of rd29A promoter. These results suggested that cAMP was an important messenger in ABA signal transduction in tobacco suspension cell.

Signal Transduction from Water Stress Perception to ABA Accumulation

To cope with unpredictably environmental perturbations and sometimes stresses, plants have evolved with some mechanisms so that these developing stresses can be sensitively perceived and the physiology can be rapidly regulated. Such perception and regulation can be a kind of feed_forward mechanism and may involve many biochemical and physiological processes and/or the expression of many genes. Although many dehydration_responsive genes have been identified, much fewer of their functions have been known. Such stress_ induced responses should include the initial perception of the dehydration signal, then the complicated signal transduction and cellular transmission until to the final gene activation or expression. As an important plant stress hormone abscisic acid (ABA) mediates many such responses. We believe that starting from the initial perception of dehydration to the gene expression leading to the stress_induced ABA biosynthesis is the most important stress signal transduction pathway among all the plant responses to stresses. Identification of the genes involved and understanding their roles during stress perception and physiological regulation shall be the most important and interesting research field in the coming years.

Study on the Signal Transduction Pathway of Plant Defense to Pathogens

The immune responses of plants to foreign pathogens have developed relevant defense mechanisms, which formed complicated disease resistant signal transduction pathways. Salicylic acid（SA）, jasmonic acid（JA）/Ethylene（ET） and brassi- nosteroid （BR） could trigger the immune response to different pathogens in plants, making the plants show some resistance to the pathogens. The study on the trans- duction pathways of these three disease-resistant signals were introduced to provide some useful suggestions for the study on the transduction of disease-resistant sig- nals in plants.

The roles of the proteasome pathway in signal transduction and neurodegenerative diseases

There are two degradation systems in mammalian cells, autophagy/lysosomal pathway and ubiquitin-proteasome pathway. Proteasome is consist of multiple protein subunits and plays important roles in degradation of short-lived cellular proteins. Recent studies reveal that proteasomal degradation system is also involved in signal transduction and regulation of various cellular functions. Dysfunction or dysregulation of proteasomal function may thus be an important pathogenic mechanism in certain neurological disorders. This paper reviews the biological functions of proteasome in signal transduction and its potential roles in neurodegenerative diseases.

Na^(+)/K^(+)-ATPase:ion pump,signal transducer,or cytoprotective protein,and novel biological functions

Na^(+)/K^(+)-ATPase is a transmembrane protein that has important roles in the maintenance of electrochemical gradients across cell membranes by transporting three Na^(+)out of and two K^(+)into cells.Additionally,Na^(+)/K^(+)-ATPase participates in Ca^(2+)-signaling transduction and neurotransmitter release by coordinating the ion concentration gradient across the cell membrane.Na^(+)/K^(+)-ATPase works synergistically with multiple ion channels in the cell membrane to form a dynamic network of ion homeostatic regulation and affects cellular communication by regulating chemical signals and the ion balance among different types of cells.Therefo re,it is not surprising that Na^(+)/K^(+)-ATPase dysfunction has emerged as a risk factor for a variety of neurological diseases.However,published studies have so far only elucidated the important roles of Na^(+)/K^(+)-ATPase dysfunction in disease development,and we are lacking detailed mechanisms to clarify how Na^(+)/K^(+)-ATPase affects cell function.Our recent studies revealed that membrane loss of Na^(+)/K^(+)-ATPase is a key mechanism in many neurological disorders,particularly stroke and Parkinson's disease.Stabilization of plasma membrane Na^(+)/K^(+)-ATPase with an antibody is a novel strategy to treat these diseases.For this reason,Na^(+)/K^(+)-ATPase acts not only as a simple ion pump but also as a sensor/regulator or cytoprotective protein,participating in signal transduction such as neuronal autophagy and apoptosis,and glial cell migration.Thus,the present review attempts to summarize the novel biological functions of Na^(+)/K^(+)-ATPase and Na^(+)/K^(+)-ATPase-related pathogenesis.The potential for novel strategies to treat Na^(+)/K^(+)-ATPase-related brain diseases will also be discussed.

Influence of CO_2 pneumoperitoneum on intracellular pH and signal transduction in cancer cells

Object: The authors studied the influence of CO2 pneumoperitoneum on intracellular pH and signal transduction arising from cancer cell multiplication in laparoscopic tumor operation. Method: They set up a simulation of pneumoperitoneum under different CO2 pressure, and then measured the variation of intracellular pH (pHi) at different time and the activity of protein kinase C (PKC) and protein phosphatase 2a (PP2a) at the end of the pneumoperitoneum. After 1 week, the concentration of cancer cells in the culture medium was calculated. Result: When the pressure of CO2 pneumoperitoneum was 0, 10, 20, 30 mmHg respectively, the average pHi was 7.273, 7.075, 6.783, 6.693 at the end of the pneumoperitoneum; PKC activity was 159.4, 168.5,178.0, 181.6 nmol/(g.min) and PP2a was 4158.3, 4066.9, 3984.0, 3878.5 nmol/(g.min) respectively. After 1 week, the cancer cells concentration was 2.15×105, 2.03×105, 2.20×105, 2.18×105 L-1. Conclusion: CO2 pneumoperitoneum could promote acidosis in cancer cells, inducing the activation of protein kinase C and deactivation of protein phosphatase 2a, but it could not accelerate the mitosis rate of the cancer cells.

Molecular signal transduction in vascular cell apoptosis

Apoptosis is a form of genetically programmed cell death, which plays a key role in regulation of cellularity in a variety of tissue and cell types including the cardiovascular tissues. Under both physiological and pathophysiological conditions, various biophysiological and biochemical factors, including mechanical forces, reactive oxygen and nitrogen species, cytokines, growth factors, oxidized lipoproteins, etc., may influence apoptosis of vascular cells. The Fas/Fas ligand/caspase death-signaling pathway, Bcl-2 protein family/mitochondria, the tumor suppressive gene p53, and the proto-oncogene c-myc may be activated in atherosclerotic lesions, and mediates vascular apoptosis during the development of atherosclerosis. Abnormal expression and dysfunction of these apoptosis-regulating genes may attenuate or accelerate vascular cell apoptosis and affect the integrity and stability of atherosclerotic plaques. Clarification of the molecular mechanism that regulates apoptosis may help design a new strategy for treatment of atherosclerosis and its major complication, the acute vascular syndromes.

Influence on Cellular Signal Transduction Pathway in Dairy Cow Mammary Gland Epithelial Cells by Galactopoietic Compound Isolated from Vaccariae segetalis

The galactopoietic mechanism of Vaccaria segetalis is still unknown. Understanding dibutyl phthalate （DBP） separated from Vaccaria segetalis on the expression of lactation signal transduction genes of mammary gland epithelial cells, including prlr, erα, akt1, socs2, pparγ and elf5, will be helpful to reveal the molecular mechanism. Western blot and qRT- PCR were used to study the change of prlr, erα, akt, socs2, pparγ, and elf5 expression at mRNA and protein level. Co- localization expression of prolactin receptor （PRLR） and estrogen receptor α （ERα） was observed by immunofluorescence; the expression changes of miRNAs （21, 125b, 143, and 195） and the secretion of β-casein and lactose were detected by qRT-PCR and RP-HPLC. The results showed that Vaccaria segetalis active compound had similar fuctions as estrogen and/or prolactin （PRL） in dairy cow mammary gland epithelial cells （DCMECs）, increased the expressions of prlr, erα, akt1, and elf5 genes, while repressed pparγ expressions. DBP promoted socs2 mRNA expression, but its protein expressions were repressed. Furthermore, both DBP and PRL could repress the expressions of miRNA-125b, miRNA-143 and miRNA- 195 in DCMECs. DBP could repress the expression of miRNA-21, while the influence of PRL on miRNA-21 was not certain. DBP could promote the lactation ability of DCMECs by regulating the ER and PRLR cellular signal transduction pathway.

Primary evidence for involvement of IP_(3) in heat-shock signal transduction in Arabidopsis

The role of inositol 1,4,5-trisphosphate （IP3） in transducing heat-shock （HS） signals was examined in Arabidopsis. The whole-plant IP3 level increased within 1 min of HS at 37℃. After 3 min of HS, the IP3 level reached a maximum 2.5 fold increase. Using the transgenic Arabidopsis plants that have AtHsp 18.2 promoter-β-glucuronidase （GUS） fusion gene, it was found that the level of GUS activity was up-regulated by the addition of caged IP3 at both non-HS and HS temperatures and was down-regulated by the phospholipase C （PLC） inhibitors {1-[6-（（ 1713-3-Methoxyestra-1,3,5（10）-trien- 7-yl）amino）hexyl]-2,5-pyrrolidinedione } （U-73122）. The intracellular-free calcium ion concentration （[Ca^2＋]i） increased during HS at 37℃ in suspension-cultured Arabidopsis cells expressing apoaequorin. Treatment with U-73122 prevented the increase of [Ca^2＋]i to some extent. Above results provided primary evidence for the possible involvement of IP3 in HS signal transduction in higher plants.

Raf kinase inhibitory protein： a signal transduction modulator and metastasis suppressor

Cells have a multitude of controls to maintain their integrity and prevent random switching from one biological state to another. Raf Kinase Inhibitory Protein （RKIP）, a member of the phosphatidylethanolamine binding protein （PEBP） family, is representative of a new class of modulators of signaling cascades that function to maintain the “yin yang” or balance of biological systems. RKIP inhibits MAP kinase （Raf-MEK-ERK）, G protein-coupled receptor （GPCR） kinase and NFkB signaling cascades. Because RKIP targets different kinases dependent upon its state ofphosphorylation, RKIP also acts to integrate crosstalk initiated by multiple environmental stimuli. Loss or depletion of RKIP results in disruption of the normal cellular stasis and can lead to chromosomal abnormalities and disease states such as cancer. Since RKIP and the PEBP family have been reviewed previously, the goal of this analysis is to provide an update and highlight some of the unique features of RKIP that make it a critical player in the regulation of cellular signaling processes.

The brassinosteroid signal transduction pathway

Steroids function as signaling molecules in both animals and plants. While animal steroid hormones are perceived by nuclear receptor family of transcription factors, brassinosteroids （BR） in plants are perceived by a cell surface receptor kinase, BRI 1. Recent studies have demonstrated that BR binding to the extracellular domain of BRI 1 induces kinase activation and dimerization with another receptor kinase, BAKI. Activated BRI 1 or BAKI then regulate, possibly indirectly, the activities of BIN2 kinase and/or BSU 1 phosphatase, which directly regulate the phosphorylation status and nuclear accumulation of two homologous transcription factors, BZRI and BES 1. BZRI and BES 1 directly bind to promoters of BR responsive genes to regulate their expression. The BR signaling pathway has become a paradigm for both receptor kinase signaling in plants and steroid signaling by cell surface receptors in general.

Interaction of major genes predisposing to hepatocellular carcinoma with genes encoding signal transduction pathways influences tumor phenotype and prognosis

Studies on rodents and humans demonstrate an inherited predisposition to hepatocellular carcinoma （HCC）. Analysis of the molecular alterations involved in the acquisition of a phenotype resistant or susceptible to hepatocarcinogenesis showed a deregulation of G1 and S phases in HCC of genetically susceptible F344 rats and a G1-S block in lesions of resistant Brown norway （BN） rats. Unrestrained extracellular signal-regulated kinase （ERK） activity linked to proteasomal degradation of dual-specificity phosphatase 1 （DUSP1）, a specific ERK inhibitor, by the CKS1-SKP2 ubiquitin ligase complex occurs in more aggressive HCC of F344 rats and humans. This mechanism is less active in HCC of BN rats and human HCC with better prognosis. Upregulation of iNos cross-talk with IKK/NF-KB and RAS/ERK pathways occurs in rodent liver lesions at higher levels in the most aggressive models represented by HCC of F344 rats and c-Myc-TGF-α transgenic mice. iNOS, IKK/NF-κB, and RAS/ERK upregulation is highest in human HCC with a poorer prognosis and positively correlates with tumor proliferation, genomic instability and microvascularization, and negatively with apoptosis. Thus, cell cycle regulation and the activity of signal transduction pathways seem to be modulated by HCC modifier genes, and differences in their efficiency influence the susceptibility to hepatocarcinogenesis and probably the prognosis of human HCC.

Role of transforming growth factor-beta1-smad signal transduction pathway in patients with hepatocellular carcinoma

AIM： To explore the role of transforming growth factorbeta1 （TGF-β1）-smad signal transduction pathway in patients with hepatocellular carcinoma. METHODS： Thirty-six hepatocellular carcinoma specimens were obtained from Qidong Liver Cancer Institute and Department of Pathology of the Second Affiliated Hospital of Nanjing Medical University. All primary antibodies （polyclonal antibodies） to TGF-β1, type H Transforming growth factor-beta receptor （TβR-Ⅱ）, nuclear factor-kappaB （NF-KB）, CD34, smad4 and smad7, secondary antibodies and immunohistochemical kit were purchased from Zhongshan Biotechnology Limited Company （Beijing, China）. The expressions of TGF-β1, TβR-Ⅱ, NF- KB, smad4 and smad7 proteins in 36 specimens of hepatocellular carcinoma （HCC） and its adjacent tissue were separately detected by immunohistochemistry to observe the relationship between TGF-β1 and TβR-Ⅱ, between NF-KB and TGF-β1, between smad4 and smad7 and between TGF-β1 or TβR-Ⅱ and microvessel density （MVD）. MVD was determined by labelling the vessel endothelial cells with CD34. RESULTS： The expression of TGF-β1, smad7 and MVD was higher in HCC tissue than in adjacent HCC tissue （P〈0.01, P〈0.05,P〈0.01 respectively）. The expression of TβR-Ⅱ and smad4 was lower in HCC tissue than in its adjacent tissue （P〈0.01, P〈0.05 respectively）. The expression of TGF-β1 protein and NF-KB protein was consistent in HCC tissue. The expression of TGF-β1 and MVD was also consistent in HCC tissue. The expression of TIER- Ⅱ was negatively correlated with that of MVD in HCC tissue. CONCLUSION： The expressions of TGF-IB1, TβR- Ⅱ, NF-KB, smad4 and smad7 in HCC tissue, which are major up and down stream factors of TGF-β1-smad signal transduction pathway, are abnormal. These factors are closely related with NVD and may play an important role in HCC angiogenesis. The inhibitory action of TGF-β1 is weakened in hepatic carcinoma cells because of abnormality of TGF-β1 receptors （such as TIBR- Ⅱ） and postreceptors （such as smad4 and smad7）. NF-KB may cause activation and production of TGF-β1.

p38 MAPK is a Component of the Signal Transduction Pathway Triggering Cold Stress Response in the MED Cryptic Species of Bemisia tabaci

Cold stress responses help insects to survive under low temperatures that would be lethal otherwise.This phenomenon might contribute to the invasion of some Bemisia tabaci cryptic species from subtropical areas to temperate regions.However,the molecular mechanisms regulating cold stress responses in whitefly are yet unclear.Mitogen-activated protein kinases（MAPKs）which including p38,ERK,and JNK,are well known for their roles in regulating metabolic responses to cold stress in many insects.In this study,we explored the possible roles of the MAPKs in response to low temperature stresses in the Mediterranean cryptic species（the Q-biotype）of the B.tabaci species complex.First,we cloned the p38 and ERK genes from the whitefly cDNA library.Next,we analyzed the activation of MAPKs during cold stress in the Mediterranean cryptic species by immuno-blotting.After cold stress,the level of phospho-p38 increased but no significant change was observed in the phosphorylation of ERK and JNK,thus suggesting that the p38 might be responsible for the defense response to low temperature stress.Furthermore,we demonstrated that：i）3 min chilling at 0°C was sufficient for the activation of p38 MAPK pathway in this whitefly;and ii）the amount of phosphorylated p38 increased significantly in the first 20 min of chilling,reversed by 60 min,and then returned to the original level by 120 min.Taken together,our results suggest that the p38 pathway is important during response to low temperature stress in the Mediterranean cryptic species of the B.tabaci species complex.

Sericin can reduce hippocampal neuronal apoptosis by activating the Akt signal transduction pathway in a rat model of diabetes mellitus

In the present study, a rat model of type 2 diabetes mellitus was established by continuous peritoneal injection of streptozotocin. Following intragastric perfusion of sericin for 35 days, blood glucose levels significantly reduced, neuronal apoptosis in the hippocampal CA1 region decreased, hippocampal phosphorylated Akt and nuclear factor kappa B expression were enhanced, but Bcl-xL/Bcl-2 associated death promoter expression decreased. Results demonstrated that sericin can reduce hippocampal neuronal apoptosis in a rat model of diabetes mellitus by regulating abnormal changes in the Akt signal transduction pathway.