Traditional Chinese medicine Pien-Tze-Huang ameliorates LPS-induced sepsis through bile acid-mediated activation of TGR5-STAT3-A20 signalling

Pien Tze Huang(PZH),a class-1 nationally protected traditional Chinese medicine(TCM),has been used to treat liver diseases such as hepatitis;however,the effect of PZH on the progression of sepsis is unknown.Here,we reported that PZH attenuated lipopolysaccharide(LPS)-induced sepsis in mice and reduced LPS-induced production of proinflammatory cytokines in macrophages by inhibiting the activation of mitogen-activated protein kinase(MAPK)and nuclear factor-kappa B(NF-κB)signalling.Mechanistically,PZH stimulated signal transducer and activator of transcription 3(STAT3)phosphorylation to induce the expression of A20,which could inhibit the activation of NF-κB and MAPK signalling.Knockdown of the bile acid(BA)receptor G protein-coupled bile acid receptor 1(TGR5)in macrophages abolished the effects of PZH on STAT3 phosphorylation and A20 induction,as well as the LPS-induced inflammatory response,suggesting that BAs in PZH may mediate its anti-inflammatory effects by activating TGR5.Consistently,deprivation of BAs in PZH by cholestyramine resin reduced the effects of PZH on the expression of phosphorylated-STAT3 and A20,the activation of NF-κB and MAPK signalling,and the production of proinflammatory cytokines,whereas the addition of BAs to cholestyramine resin-treated PZH partially restored the inhibitory effects on the production of proinflammatory cytokines.Overall,our study identifies BAs as the effective components in PZH that activate TGR5-STAT3-A20 signalling to ameliorate LPS-induced sepsis.

Reduction of the oxidative damage to H_(2)O_(2)-induced HepG2 cells via the Nrf2 signalling pathway by plant flavonoids Quercetin and Hyperoside

Hyperoside and quercetin are similar in molecular structures.In this study,the antioxidant regulatory targets of hyperoside and quercetin are mainly in the nuclear factor(erythroid-2-derived)-related factor 2(Nrf2)pathway predicted by network pharmacology.And the antioxidant effect and mechanism of hyperoside and quercetin were measured and compared in H_(2)O_(2)-induced Hep G2 cells and Caenorhabditis elegans.The findings indicated that quercetin was more effective than hyperoside in reducing oxidative damage,which was proved by improved cell viability,decreased reactive oxygen species(ROS)production,decreased cellular apoptosis,and alleviated mitochondrial damage.In addition,quercetin was more efficient than hyperoside in enhancing the expression of Nrf2-associated m RNAs,increasing the activities of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),and catalase(CAT),and reducing the cellular malondialdehyde(MDA)content.Quercetin was superior to hyperoside in prolonging the lifespan of worms,decreasing the accumulation of lipofuscin,inhibiting ROS production,and increasing the proportion of skn-1 in the nucleus.With the Nrf2 inhibitor ML385,we verified that quercetin and hyperoside primarily protected the cells against oxidative damage via the Nrf2 signalling pathway.Furthermore,molecular docking and dynamics simulations demonstrated that the quercetin-Kelch-like ECH-associated protein 1(Keap1)complex was more stable than the hyperoside-Keap1 complex.The stable structure of the complex might hinder the binding of Nrf2 and Keap1 to release Nrf2 and facilitate its entry into the nucleus to play an antioxidant role.Overall,quercetin had a better antioxidant than hyperoside.

Correlation between Wnt Signalling Inhibitors (Dickkopf-1 & Sclerostin) and the Intimal Medial Thickness in Children on Maintenance Hemodialysis

Background: Wnt signalling inhibitors (Dickkopf-1 and Sclerostin) signalling play a role in vascular development and may contribute to calcification. Aim: To investigate the association between Dickkopf-1 and sclerostin serum concentrations in children undergoing maintenance hemodialysis with intimal medial thickness and peak systolic velocity of the main arteries. Patients and Methods: A study was conducted on 40 children undergoing maintenance hemodialysis and controls of the same age and sex. The study measured the initial medial thickness (IMT) and peak systolic velocity (PSV) of the main vessels (carotid, ulnar, and femoral). Dickkopf-1 and sclerostin serum levels in both groups were assessed, and a routine investigation was performed. Results: The findings indicate that the levels of serum Dickkopf-1 and Sclerostin were significantly higher in the hemodialysis group 2540.65 (2215.4 - 2909.2 pg/ml) and 1.17 (0.85 - 2.03 ng/ml)respectively (P = 0.001), compared to their control group it was 1110.45 (885.45 - 1527.65 pg/ml) and 0.28 (0.25 - 0.32 ng/ml)) respectively P = 0.001. Additionally, there was a significant increase in intima-media thickness (IMT) with a decrease in peak systolic velocity (PSV) in the main blood vessels, including the carotid, ulnar, and femoral arteries. A significant correlation was also observed between Dickkopf-1 and sclerostin levels and IMT of the carotid, ulnar, and femoral arteries. Conclusion: Wnt signalling inhibitors (Dickkopf-1 and Sclerostin) exert effects beyond the bone and significantly contribute to early vascular calcification in pediatric patients undergoing maintenance hemodialysis.

Early monitoring values of oncogenic signalling molecules for hepatocellular carcinoma

The prevention and early diagnosis of liver cancer remains a global medical challenge.During the malignant transformation of hepatocytes,a variety of oncogenic cellular signalling molecules,such as novel high mobility group-Box 3,angiopoietin-2,Golgi protein 73,glypican-3,Wnt3a(a signalling molecule in the Wnt/β-catenin pathway),and secretory clusterin,can be expressed and secreted into the blood.These signalling molecules are derived from different signalling pathways and may not only participate in the malignant transformation of hepatocytes but also become early diagnostic indicators of hepatocarcinogenesis or specific targeted molecules for hepatocellular carcinoma therapy.This article reviews recent progress in the study of several signalling molecules as sensitive biomarkers for monitoring hepatocarcinogenesis.

XB130 inhibits healing of diabetic skin ulcers through the PI3K/Akt signalling pathway

BACKGROUND Diabetic skin ulcers,a significant global healthcare burden,are mainly caused by the inhibition of cell proliferation and impaired angiogenesis.XB130 is an adaptor protein that regulates cell proliferation and migration.However,the role of XB130 in the development of diabetic skin ulcers remains unclear.AIM To investigate whether XB130 can regulate the inhibition of proliferation and vascular damage induced by high glucose.Additionally,we aim to determine whether XB130 is involved in the healing process of diabetic skin ulcers,along with its molecular mechanisms.METHODS We conducted RNA-sequencing analysis to identify the key genes involved in diabetic skin ulcers.We investigated the effects of XB130 on wound healing using histological analyses.In addition,we used reverse transcription-quantitative polymerase chain reaction,Western blot,terminal deoxynucleotidyl transferasemediated dUTP nick end labeling staining,immunofluorescence,wound healing,and tubule formation experiments to investigate their effects on cellular processes in human umbilical vein endothelial cells(HUVECs)stimulated with high glucose.Finally,we performed functional analysis to elucidate the molecular mechanisms underlying diabetic skin ulcers.RESULTS RNA-sequencing analysis showed that the expression of XB130 was up-regulated in the tissues of diabetic skin ulcers.Knockdown of XB130 promoted the healing of skin wounds in mice,leading to an accelerated wound healing process and shortened wound healing time.At the cellular level,knockdown of XB130 alleviated high glucose-induced inhibition of cell proliferation and angiogenic impairment in HUVECs.Inhibition of the PI3K/Akt pathway removed the proliferative effects and endothelial protection mediated by XB130.CONCLUSION The findings of this study indicated that the expression of XB130 is up-regulated in high glucose-stimulated diabetic skin ulcers and HUVECs.Knockdown of XB130 promotes cell proliferation and angiogenesis via the PI3K/Akt signalling pathway,which accelerates the healing of diabetic skin ulcers.

Novel insights into mTOR signalling pathways: A paradigm for targeted tumor therapy

As a crucial protein kinase,the mammalian target of rapamycin(mTOR)intimately controls essential cellular processes like cell development,proliferation,metabolism,and other crucial activities.Different cancers and disorders have been linked to imbalances in mTOR's regulatory systems.Multiple mTOR inhibitor therapy has recently acquired popularity as a method of treating cancers brought on by abnormal signal transduction pathways.We also explore potential processes behind tumor cell resistance to mTOR inhibitors and suggest workarounds to overcome this challenge.We hold the potential to pioneer cutting-edge methods for tumor therapy by methodically examining the complex mTOR signaling system and its regulatory complexity.Increasing our knowledge of mTOR-related mechanisms not only creates opportunities for cutting-edge methods to target and treat cancers but also has the potential to improve patient outcomes and general quality of life significantly.This review paper explores the most recent developments in understanding mTOR signaling pathways and the use of mTOR inhibitors in treating tumors.

Targeting key signalling pathways in oesophageal adenocarcinoma:A reality for personalised medicine?

Cancer treatments are rapidly changing.Curative treatment for oesophageal adenocarcinoma currently involves surgery and cytotoxic chemotherapy or chemoradiotherapy.Outcomes for both regimes are generally poor as a result of tumor recurrence.We have reviewed the key signalling pathways associated with oesophageal adenocarcinomas and discussed the recent trials of novel agents that attempt to target these pathways.There are many trials underway with the aim of improving survival in oesophageal cancer.Currently,phase 2 and 3 trials are focused on MAP kinase inhibition,either through inhibition of growth factor receptors or signal transducer proteins.In order to avoid tumor resistance,it appears to be clear that targeted therapy will be needed to combat the multiple signalling pathways that are in operation in oesophageal adenocarcinomas.This may be achievable in the future with the advent of gene signatures and a combinatorial approach.

MIF May Participate in Pathogenesis of Polycystic Ovary Syndrome in Rats through MAPK Signalling pathway

The polycystic ovary syndrome (PCOS) model was established in fats and correlation between the expression of macrophage migration inhibitory factor (MIF) and cytokinesis with the MAPK signalling pathway in the rat ovary was measured. The PCOS model in rats was established by dehydroepiandrosterone (DHEA).Thirty sexually immature female Sprague-Dawley rats were randomly and equally assigned to three groups:control group,PCOS group,and PCOS with high-fat diet (HFD) group.Serum hormones were assayed by radioimmunoassay (RIA).The ovaries'were immunohistochemically stained with MIF,and the expression of MIF,p-JNK and p-p38 was detected by Western blotting in ovaries.The serum testosterone level,LH concentration,LH/FSH ratio,fasting insulin level and HOMA IR index in the PCOS group (6.077±0.478,13.809±1.701,1.820±0.404,10.83±1.123 and 1.8692±0.1096)and PCOS with HFD group (6.075±0.439,14.075±1.927,1.779±0.277,10.20±1.377 and 1.7736±0.6851)were significantly higher than those in the control group (4.949±0.337, 2.458±0.509,1.239±0.038,9.53±0.548 and 1.5329±0.7363),but there was no significant difference between the PCOS group and PCOS with HFD group.The expression levels of MIF,p-JNK,and p-p38 in the PCOS group (0.4048±0.013,0.6233±0.093 and 0.7987±0.061)and PCOS withHFD group (0.1929±0.012,0.3346±0.103 and 0.3468±0.031)were obviously higher than those in control group (0.2492±0.013, 0.3271±0.093 and 0.3393±0.061),but no Significant difference was observed between PCOS group and PCOS with HFD group.It was suggested that MIF may participate in the pathogenesis of PCOS through the MAPK signalling pathway in PCOS rats induced by DHEA.

Dickkopfs and Wnt/β-catenin signalling in liver cancer

Liver cancer is the fifth and seventh most common cause of cancer in men and women,respectively.Wnt/β-catenin signalling has emerged as a critical player in both the development of normal liver as well as an oncogenic driver in hepatocellular carcinoma(HCC).Based on the current understanding,this article summarizes the possible mechanisms for the aberrant activation of this pathway with specific focus on HCC.Furthermore,we will discuss the role of dickkopfs(DKKs)in regulating Wnt/β-catenin signalling,which is poorly understood and understudied.DKKs are a family of secreted proteins that comprise at least four members,namely DKK1-DKK4,which act as inhibitors of Wnt/β-catenin signalling.Nevertheless,not all members antagonize Wnt/β-catenin signalling.Their functional significance in hepatocarcinogenesis remains to be further characterized for which these studies should provide new insights into the regulatory role of DKKs in Wnt/β-catenin signalling in hepatic carcinogenesis.Because of the important oncogenic roles,there are an increasing number of therapeutic molecules targetingβ-catenin and the Wnt/β-catenin pathway for potential therapy of HCC.

p21-activated kinase signalling in pancreatic cancer: New insights into tumour biology and immune modulation

Pancreatic cancer is one of the most aggressive and lethal malignancies worldwide, with a very poor prognosis and a five-year survival rate less than 8%. This dismal outcome is largely due to delayed diagnosis, early distant dissemination and resistance to conventional chemotherapies. Kras mutation is a well-defined hallmark of pancreatic cancer, with over 95% of cases harbouring Kras mutations that give rise to constitutively active forms of Kras. As important down-stream effectors of Kras, p21-activated kinases(PAKs) are involved in regulating cell proliferation, apoptosis, invasion/migration and chemo-resistance. Immunotherapy is now emerging as a promising treatment modality in the era of personalized anti-cancer therapeutics. In this review, basic knowledge of PAK structure and regulation is briefly summarised and the pivotal role of PAKs in Kras-driven pancreatic cancer is highlighted in terms of tumour biology and chemoresistance. Finally, the involvement of PAKs in immune modulation in the tumour microenvironment is discussed and the potential advantages of targeting PAKs are explored.

Exogenous p27KIP1 expression induces anti-tumour effects and inhibits the EGFR/PI3K/Akt signalling pathway in PC3 cells

p27 is a cyclin-dependent kinase inhibitor that regulates the progression of cells from G1 to S phase of the cell cycle. Loss of p27 has been associated with disease progression and with an unfavourable outcome in prostate cancer. In this study, we investigated whether exogenous p27 expression in the human androgen-independent prostate cancer PC3 cell line had any effect on cell growth, and we studied the molecular mechanisms involved. p27 expression was restored in PC3 cells by plasmid delivery. Cell proliferation and apoptosis were assessed in PC3 cells transfected with p27. We also investigated the effects of p27 on the epidermal growth factor receptor （EGFR）/ phosphatidylinositol 3-kinase （PI3K）/Akt signalling pathway in PC3 cells. By restoring p27 expression in PC3 cells, we observed that p27 reduced proliferation and induced arrest in G0/G1 phase. Moreover, p27-transfected PC3 cells underwent apoptosis, as shown by flow cytometric analysis and western blotting analysis of Bcl-2, Bax, Bad, caspase-3 and poly（ADP-ribose）polymerase expression. Furthermore, the p27-induced anti-tumour action corre- lated with inhibition of the EGFR/PI3K/Akt signalling pathway, as confirmed by western blotting analysis and densitometry of EGFR, PI3K （p85）, Akt and p-Akts473 expression. Our results suggest that exogenous expression of p27 inhibits the proliferation of PC3 cells through induction of G1 arrest and apoptosis, and this process correlates with inhibition of the EGFR/PI3K/Akt signalling pathway.

Glutamate receptors and glutamatergic signalling in the peripheral nerves

In the peripheral nervous system,the vast majority of axons are accommodated within the fibre bundles that constitute the peripheral nerves.Axons within the nerves are in close contact with myelinating glia,the Schwann cells that are ideally placed to respond to,and possibly shape,axonal activity.The mechanisms of intercellular communication in the peripheral nerves may involve direct contact between the cells,as well as signalling via diffusible substances.Neurotransmitter glutamate has been proposed as a candidate extracellular molecule mediating the cross-talk between cells in the peripheral nerves.Two types of experimental findings support this idea:first,glutamate has been detected in the nerves and can be released upon electrical or chemical stimulation of the nerves;second,axons and Schwann cells in the peripheral nerves express glutamate receptors.Yet,the studies providing direct experimental evidence that intercellular glutamatergic signalling takes place in the peripheral nerves during physiological or pathological conditions are largely missing.Remarkably,in the central nervous system,axons and myelinating glia are involved in glutamatergic signalling.This signalling occurs via different mechanisms,the most intriguing of which is fast synaptic communication between axons and oligodendrocyte precursor cells.Glutamate receptors and/or synaptic axon-glia signalling are involved in regulation of proliferation,migration,and differentiation of oligodendrocyte precursor cells,survival of oligodendrocytes,and re-myelination of axons after damage.Does synaptic signalling exist between axons and Schwann cells in the peripheral nerves?What is the functional role of glutamate receptors in the peripheral nerves?Is activation of glutamate receptors in the nerves beneficial or harmful during diseases?In this review,we summarise the limited information regarding glutamate release and glutamate receptors in the peripheral nerves and speculate about possible mechanisms of glutamatergic signalling in the nerves.We highlight the necessity of further research on this topic because it should help to understand the mechanisms of peripheral nervous system development and nerve regeneration during diseases.

Cell signalling pathways underlying induced pluripotent stem cell reprogramming

Induced pluripotent stem(i PS) cells, somatic cells reprogrammed to the pluripotent state by forced expression of defined factors, represent a uniquely valuable resource for research and regenerative medicine. However, this methodology remains inefficient due to incomplete mechanistic understanding of the reprogramming process. In recent years, various groups have endeavoured to interrogate the cell signalling that governs the reprogramming process, including LIF/STAT3, BMP, PI3 K, FGF2, Wnt, TGFβ and MAPK pathways, with the aim of increasing our understanding and identifying new mechanisms of improving safety, reproducibility and efficiency. This has led to a unified model of reprogramming that consists of 3 stages: initiation, maturation and stabilisation. Initiation of reprogramming occurs in almost all cells that receive the reprogramming transgenes; most commonly Oct4, Sox2, Klf4 and c Myc, and involves a phenotypic mesenchymal-to-epithelial transition. The initiation stage is also characterised by increased proliferation and a metabolic switch from oxidative phosphorylation to glycolysis. The maturation stage is considered the major bottleneck within the process, resulting in very few "stabilisation competent" cells progressing to the final stabilisation phase. To reach this stage in both mouse and human cells, pre-i PS cells must activate endogenous expression of the core circuitry of pluripotency, comprising Oct4, Sox2, and Nanog, and thus reach a state of transgene independence. By the stabilisation stage, i PS cells generally use the same signalling networks that govern pluripotency in embryonic stem cells. These pathways differ between mouse and human cells although recent work has demonstrated that this is context dependent. As i PS cell generation technologies move forward, tools are being developed to interrogate the process in more detail, thus allowing a greater understanding of this intriguing biological phenomenon.

RNA-Seq Study Reveals AP2-Domain-Containing Signalling Regulators Involved in Initial Imbibition of Seed Germination in Rice

A number of internal signals are required for seed germination.However,the precise signalling responses in the initial imbibition of seed germination are not yet fully understood in rice.In this study,the RNA sequencing(RNA-Seq)approach was conducted in 8 h imbibed seeds to understand the signalling responses in the initial imbibition of rice seed germination.A total of 563 differentially expressed genes(DEGs)with at least 4-fold change were identified in 8 h imbibed seeds compared to dry seeds.MapMan analysis revealed that the majority of signalling response-related DEGs were hormone-and transcription factor-related genes,in which the largest number of DEGs belong to the AP2-domain-containing regulators,and their expressions were significantly induced in the initial imbibition of seed germination in rice.Moreover,at least five AP2-domain-containing transcription factor OsDREBs were identified in the initial imbibition of rice seed germination,and the expressions of 251 DEGs were putatively regulated by OsDREBs through the dehydration-responsive element(DRE)cis-element assay.It suggested that the OsDREBs might play important roles in the regulation of initial seed imbibition in rice.The identified genes provide a valuable resource to study the signalling regulation of seed germination in the future.

Notch signalling pathway in development of cholangiocarcinoma

Cholangiocarcinoma(CCA)comprises of extra-hepatic cholangiocarcinoma and intrahepatic cholangiocarcinoma cancers as a result of inflammation of epithelium cell lining of the bile duct.The incidence rate is increasing dramatically worldwide with highest rates in Eastern and South Asian regions.Major risk factors involve chronic damage and inflammation of bile duct epithelium from primary sclerosing cholangitis,chronic hepatitis virus infection,gallstones and liver fluke infection.Various genetic variants have also been identified and as CCA develops on the background of biliary inflammation,diverse range of molecular mechanisms are involved in its progression.Among these,the Notch signalling pathway acts as a major driver of cholangiocarcinogenesis and its components(receptors,ligands and downstream signalling molecules)represent a promising therapeutic targets.Gamma-Secretase Inhibitors have been recognized in inhibiting the Notch pathway efficiently.A comprehensive knowledge of the molecular pathways activated by the Notch signalling cascade as well as its functional crosstalk with other signalling pathways provide better approach in developing innovative therapies against CCA.

Optimal Active Defence Using Dynamic Multi-Stage Signalling Game

Nowadays, security defence of network uses the game theory, which mostly applies complete information game model or even the static game model. To get closer to the actual network and defend actively, we propose a network attack-defence game model by using signalling game, which is modelled in the way of dynamic and incomplete information. We improve the traditional attack-defence strategies quantization method to meet the needs of the network signalling game model. Moreover, we give the calculation of the game equilibrium and analyse the optimal defence scheme. Finally, we analyse and verify effectiveness of the model and method through a simulation experiment.

Update on vascular endothelial Ca^(2+) signalling:A tale of ion channels,pumps and transporters

A monolayer of endothelial cells (ECs) lines the lumen of blood vessels and forms a multifunctional transducing organ that mediates a plethora of cardiovascular processes. The activation of ECs from as state of quiescence is, therefore, regarded among the early events leading to the onset and progression of potentially lethal diseases, such as hypertension, myocardial infarction, brain stroke, and tumor. Intracellular Ca2+ signals have long been know to play a central role in the complex network of signaling pathways regulating the endothelial functions. Notably, recent work has outlined how any change in the pattern of expression of endothelial channels, transporters and pumps involved in the modulation of intracellular Ca2+ levels may dramatically affect whole body homeostasis. Vascular ECs may react to both mechanical and chemical stimuli by generating a variety of intracellular Ca2+ signals, ranging from brief, localized Ca2+ pulses to prolonged Ca2+ oscillations engulfing the whole cytoplasm. The well-defined spatiotemporal profile of the subcellular Ca2+ signals elicited in ECs by specific extracellular inputs depends on the interaction between Ca2+ releasing channels, which arelocated both on the plasma membrane and in a number of intracellular organelles, and Ca2+ removing systems. The present article aims to summarize both the past and recent literature in the field to provide a clear-cut picture of our current knowledge on the molecular nature and the role played by the components of the Ca2+ machinery in vascular ECs under both physiological and pathological conditions.

Purinergic signalling in neuroregeneration

Purinergic signalling,adenosine 5′-triphosphate（ATP）as an extracellular signalling molecule,was proposed in 1972（Burnstock,1972）.However,it was not generally accepted until the early 1990s when receptors for ATP and its breakdown product adenosine were cloned and characterised（Ralevic and Burnstock,1998）.Four P1（adenosine）receptors are recognised（A1,A2A,A2B and A3）.

The suppressor of cytokine signalling 2(SOCS2),traumatic brain injury and microglial/macrophage regulation

Traumatic brain injury （TBI） results in a range of neuroinflam- matory events that vary depending on the type and extent of in- jury. Central to this is the activation of tissue resident microglia and infiltration of peripheral macrophages, which phagocytose debris and/or secrete a range of cytokines, chemokines and oth- er factors which modify the injured environment to promote or inhibit repair （Schwartz et al., 2013）. The reactive macro- phages/microglia are broadly divided into two categories.

Spatial signalling mediated by the transforming growth factor-β signalling pathway during tooth formation

Tooth development relies on sequential and reciprocal interactions between the epithelial and mesenchymal tissues, and it is continuously regulated by a variety of conserved and specific temporal-spatial signalling pathways. It is well known that suspensions of tooth germ cells can form tooth-like structures after losing the positional information provided by the epithelial and mesenchymal tissues. However, the particular stage in which the tooth germ cells start to form tooth-like structures after losing their positional information remains unclear. In this study, we investigated the reassociation of tooth germ cells suspension from different morphological stages during tooth development and the phosphorylation of Smad2/3 in this process. Four tooth morphological stages were designed in this study. The results showed that tooth germ cells formed odontogenic tissue at embryonic day （E） 14.5, which is referred to as the cap stage, and they formed tooth-like structures at E16.5, which is referred to as the early bell stage, and E18.5, which is referred to as the late bell stage. Moreover, the transforming growth factor-β signalling pathway might play a role in this process.