Receptor-mediated Signal Transduction Research Articles

Ultrasonic Control of Protein Splicing by Split Inteins.

Utilizing ultrasound as an external stimulus to remotely modulate the activity of proteins is an important aspect of sonopharmacology and establishes the basis for the emerging field of sonogenetics. Here, we describe an ultrasound-responsive protein splicing system that enables spatiotemporal control of split-intein-mediated protein ligation. The system utilizes engineered split inteins that are caged and can be activated by thrombin released from a high molar mass DNA-based carrier under focused ultrasound sonication. This approach represents a general method for controlling the functions of proteins of interest by ultrasound, as demonstrated here by the controlled synthesis of the superfolder green fluorescence protein (GFP) and calcitonin. Furthermore, calcitonin receptor-mediated signal transduction in cells was triggered by this system in vitro without harming cell viability. By expanding the sonogenetic toolbox with protein splicing technologies, this study provides a possible pathway to deploy ultrasound for remotely controlling a variety of protein functions in deep tissue in the future.

Ginsenoside Re promotes proliferation of murine bone marrow mesenchymal stem cells in vitro through estrogen-like action.

Ginsenoside Re (GS-Re) is a major saponin monomer found in Panax ginseng Meyer. It has been shown to exhibit a wide range of biological and pharmacological activities. This study aimed to investigate the effect of GS-Re on the proliferation of murine bone marrow-derived MSCs in vitro and to assess whether its effect is dependent on the estrogen receptor-mediated signal transduction. CFU colony formation assay, cell counting, and colorimetric MTT test were employed to examine effects of GS-Re on the in vitro proliferation of MSCs and the mechanisms of the underlying effect were detected by flow cytometric analysis, immunofluorescence staining for BrdU, and Western blotting. GS-Re dose-dependently promoted the in vitro proliferation of murine bone marrow-derived MSCs over a range of concentrations of 0.5 ~ 20µmol/L, and this effect approached the maximal level at 10µmol/L. Increases in the expression level of phosphorylated extracellular signal-regulated kinases 1/2 (p-ERK1/2) were observed in the passaged MSCs treated with 10µmol/L of GS-Re. These effects of GS-Re on the MSCs were significantly counteracted by the addition of ICI 182, 780 (an estrogen receptor antagonist) to the culture media. We concluded that GS-Re is able to exert a proliferation-promoting effect on murine bone marrow-derived mesenchymal stem cells in vitro, and its action is involved in the estrogen receptor-mediated signaling.

Standardized Production of Anti-Desmoglein 3 Antibody AK23 for Translational Pemphigus Vulgaris Research.

Antibody-mediated receptor activation is successfully used to develop medical treatments. If the activation induces a pathological response, such antibodies are also excellent tools for defining molecular mechanisms of target receptor malfunction and designing rescue therapies. Prominent examples are naturally occurring autoantibodies inducing the severe blistering disease pemphigus vulgaris (PV). In the great majority of patients, the antibodies bind to the adhesion receptor desmoglein 3 (Dsg3) and interfere with cell signaling to provoke severe blistering in the mucous membranes and/or skin. The identification of a comprehensive causative signaling network downstream of antibody-targeted Dsg3 receptors (e.g., shown by pharmacological activators or inhibitors) is currently being discussed as a basis to develop urgently needed first-line treatments for PV patients. Although polyclonal PV IgG antibodies have been used as proof of principle for pathological signal activation, monospecific anti-Dsg3 antibodies are necessary and have been developed to identify pathological Dsg3 receptor-mediated signal transduction. The experimental monospecific PV antibody AK23, produced from hybridoma cells, was extensively tested in our laboratory in both in vitro and in vivo models for PV and proved to recapitulate the clinicopathological features of PV when generated using the standardized production and purification protocols described herein. © 2024 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Bovine IgG stripping from FBS and quality control Basic Protocol 2: AK23 hybridoma expansion and IgG production Basic Protocol 3: AK23 IgG purification Basic Protocol 4: AK23 IgG quality control Support Protocol 1: Detection of endotoxin levels Support Protocol 2: Detection and removal of mycoplasma.

Mesenchymal cells as the biological modifiers for stimulation and regulation of cellular and molecular healing and regeneration

Biologic modifiers are materials or proteins and factors that have the potential to alter the host tissue so as to stimulate or regulate the wound healing process. Classic examples of biologic modifiers are growth factors. Bioengineered materials are widely utilized due to their biocompatibility and degradability, as well as their moisturizing and antibacterial properties. One field of their application in medicine is to treat wounds by promoting tissue regeneration and improving wound healing. In addition to creating a physical and chemical barrier against primary infection, the mechanical stability of the porous structure of biomaterials provides an extracellular matrix (ECM)-like niche for cells. Growth factors are polypeptide molecules that control the growth, differentiation, and metabolism of cells during each of the three phases of wound healing. They are present throughout the body in only minute concentrations yet exert a powerful local influence on wound repair. They interact with specific receptors in the cell surface, leading to specific responses determined by the receptor-mediated signal transduction pathways within the target cells. Growth factors (GFs) and cytokines, which are secreted by the cells, are essential parts of the complex process of tissue regeneration and wound healing.

Role of Vasoactive Hormone-Induced Signal Transduction in Cardiac Hypertrophy and Heart Failure.

Heart failure is the common concluding pathway for a majority of cardiovascular diseases and is associated with cardiac dysfunction. Since heart failure is invariably preceded by adaptive or maladaptive cardiac hypertrophy, several biochemical mechanisms have been proposed to explain the development of cardiac hypertrophy and progression to heart failure. One of these includes the activation of different neuroendocrine systems for elevating the circulating levels of different vasoactive hormones such as catecholamines, angiotensin II, vasopressin, serotonin and endothelins. All these hormones are released in the circulation and stimulate different signal transduction systems by acting on their respective receptors on the cell membrane to promote protein synthesis in cardiomyocytes and induce cardiac hypertrophy. The elevated levels of these vasoactive hormones induce hemodynamic overload, increase ventricular wall tension, increase protein synthesis and the occurrence of cardiac remodeling. In addition, there occurs an increase in proinflammatory cytokines and collagen synthesis for the induction of myocardial fibrosis and the transition of adaptive to maladaptive hypertrophy. The prolonged exposure of the hypertrophied heart to these vasoactive hormones has been reported to result in the oxidation of catecholamines and serotonin via monoamine oxidase as well as the activation of NADPH oxidase via angiotensin II and endothelins to promote oxidative stress. The development of oxidative stress produces subcellular defects, Ca2+-handling abnormalities, mitochondrial Ca2+-overload and cardiac dysfunction by activating different proteases and depressing cardiac gene expression, in addition to destabilizing the extracellular matrix upon activating some metalloproteinases. These observations support the view that elevated levels of various vasoactive hormones, by producing hemodynamic overload and activating their respective receptor-mediated signal transduction mechanisms, induce cardiac hypertrophy. Furthermore, the occurrence of oxidative stress due to the prolonged exposure of the hypertrophied heart to these hormones plays a critical role in the progression of heart failure.

Hormone Metabolites and Herbal Bioactive Agents: Potential Drug Candidates for the Luminal A Breast Cancer subtype

Background: Hormone receptor positive, human epidermal growth factor receptor negative Luminal A breast cancer subtype responds to targeted endocrine therapy, signal transduction inhibitors and cyclin dependent kinase inhibitors. Estrogen and progesterone receptor mediated signal transduction involves receptor-DNA binding and transcriptional activation of downstream target genes. In addition to hormone receptor signaling, cellular metabolism of estradiol and progesterone exhibit distinct roles in cancer growth modulation. Targeted therapy is associated with systemic toxicity, therapy resistance and emergence of chemo-resistant cancer initiating stem cells. These limitations emphasize identification of testable drug candidates for therapy resistant breast cancer. Cellular metabolism of ovarian steroid hormones generates oxidative metabolites with distinct growth modulating effects. Anti-proliferative metabolites may represent potential drug candidates. Objectives: The objectives of the present review are to provide i) Systematic discussion of published evidence relevant to the role of ovarian steroid hormone metabolism in growth modulatory effects on cancer progression, ii) Evidence for applicability of Luminal A breast cancer and drug-resistant cancer stem cell models to identify mechanistic leads for efficacy of anti-proliferative hormone metabolites, and iii) Future research directions for clinical translatability of patient derived preclinical data. Conclusions: Collectively, present evidence validates experimental approaches to identify hormone metabolites as potential drug candidates for therapy-resistant breast cancer. .

Lipid rafts mediate multilineage differentiation of human dental pulp-derived stem cells (DPSCs).

Cell outer membranes contain glycosphingolipids and protein receptors, which are integrated into glycoprotein domains, known as lipid rafts, which are involved in a variety of cellular processes, including receptor-mediated signal transduction and cellular differentiation process. In this study, we analyzed the lipidic composition of human Dental Pulp-Derived Stem Cells (DPSCs), and the role of lipid rafts during the multilineage differentiation process. The relative quantification of lipid metabolites in the organic fraction of DPSCs, performed by Nuclear Magnetic Resonance (NMR) spectroscopy, showed that mono-unsaturated fatty acids (MUFAs) were the most representative species in the total pool of acyl chains, compared to polyunsatured fatty acids (PUFAs). In addition, the stimulation of DPSCs with different culture media induces a multilineage differentiation process, determining changes in the gangliosides pattern. To understand the functional role of lipid rafts during multilineage differentiation, DPSCs were pretreated with a typical lipid raft affecting agent (MβCD). Subsequently, DPSCs were inducted to differentiate into osteoblast, chondroblast and adipoblast cells with specific media. We observed that raft-affecting agent MβCD prevented AKT activation and the expression of lineage-specific mRNA such as OSX, PPARγ2, and SOX9 during multilineage differentiation. Moreover, this compound significantly prevented the tri-lineage differentiation induced by specific stimuli, indicating that lipid raft integrity is essential for DPSCs differentiation. These results suggest that lipid rafts alteration may affect the signaling pathway activated, preventing multilineage differentiation.

Janus Kinase 3 phosphorylation and the JAK/STAT pathway are positively modulated by follicle-stimulating hormone (FSH) in bovine granulosa cells

Janus kinase 3 (JAK3) is a member of the JAK family of tyrosine kinase proteins involved in cytokine receptor-mediated intracellular signal transduction through the JAK/STAT signaling pathway. JAK3 was previously shown as differentially expressed in granulosa cells (GC) of bovine pre-ovulatory follicles suggesting that JAK3 could modulate GC function and activation/inhibition of downstream targets. We used JANEX-1, a JAK3 inhibitor, and FSH treatments and analyzed proliferation markers, steroidogenic enzymes and phosphorylation of target proteins including STAT3, CDKN1B/p27Kip1 and MAPK8IP3/JIP3. Cultured GC were treated with or without FSH in the presence or not of JANEX-1. Expression of steroidogenic enzyme CYP11A1, but not CYP19A1, was upregulated in GC treated with FSH and both were significantly decreased when JAK3 was inhibited. Proliferation markers CCND2 and PCNA were reduced in JANEX-1-treated GC and upregulated by FSH. Western blots analyses showed that JANEX-1 treatment reduced pSTAT3 amounts while JAK3 overexpression increased pSTAT3. Similarly, FSH treatment increased pSTAT3 even in JANEX-1-treated GC. UHPLC-MS/MS analyses revealed phosphorylation of specific amino acid residues within JAK3 as well as CDKN1B and MAPK8IP3 suggesting possible activation or inhibition post-FSH or JANEX-1 treatments. We show that FSH activates JAK3 in GC, which could phosphorylate target proteins and likely modulate other signaling pathways involving CDKN1B and MAPK8IP3, therefore controlling GC proliferation and steroidogenic activity.

Information potential of an ubiquitous phytochemical cue.

This article is a Commentary on Li et al. (2023), 238: 2099–2112.

Whole-genome sequencing revealed a novel long-range deletion mutation spanning GNAS in familial pseudohypoparathyroidism.

Pseudohypoparathyroidism (PHP) is a series of diseases related to pathological changes and neurocognitive and endocrine abnormalities, mainly due to the GNAS mutation on chromosome 20q13.2, which weakens receptor-mediated hormone signal transduction. Considering its complex genetic and epigenetic characteristics, GNAS may produce complex clinical phenotypes in families or sporadic cases. This study presented a case of familial PHP caused by a deletion mutation in the 20q13.2 region. The proband and her second daughter had PHP, and the proband's mother had pseudo-PHP. Whole-genome sequencing revealed that the proband had an 849.81 kb deletion spanning GNAS near the maternal 20q13.2 chromosome. Multiplex ligation-dependent probe amplification methylation analysis indicated that the proband as well as her mother and second daughter had seemingly abnormal GNAS methylation. This is different from the phenotype (feeding difficulty, slow growth, and special facial features) of previously reported cases with the deletion of fragments near the 20q13.2 chromosome. This report demonstrated the variability of 20q13.2 deletion phenotypes and the clinical importance of using multiple molecular genetic detection methods.

PARP1 Inhibition and Effect on Burn Injury-Induced Inflammatory Response and Cardiac Function.

Burn injury induces multiple signaling pathways leading to a significant inflammatory storm that adversely affects multiple organs, including the heart. Poly (ADP-ribose) polymerase inhibitor 1 (PARP1) inhibition, with specific agents such as N-(5,6-Dihydro-6-oxo-2-phenanthridinyl)-2-acetamide (PJ34), is effective in reducing oxidative stress and cytokine expression in the heart. We hypothesized that PARP1 inhibition would reduce inflammatory signaling and protect against burn injury-induced cardiac dysfunction. Male Sprague-Dawley rats (8 weeks old, 300 to 350 g) were randomly assigned to sham injury (Sham), 60% total body surface area burn (24 hours post burn), or 60% total body surface area burn with intraperitoneal administration of PJ34 (20 mg/kg, 24 hours post burn + PJ34) and sacrificed 24 hours after injury. Cardiac function was determined using Vevo 2100 echocardiography. Genetic expression of 84 specific toll-like receptor-mediated signal transduction and innate immunity genes were examined using microarray to evaluate cardiac tissue. Qiagen GeneGlobe Data Analysis Center was used to analyze expression, and genetic clustering was performed using TreeView V2.0.8 software. Real-time quantitative polymerase chain reaction was used to validate identified differentially expressed genes. Burn injury significantly altered multiple genes in the toll-like receptor signaling, interleukin-17 signaling, tumor necrosis factor signaling, and nuclear factor-κB signaling pathways and led to significant cardiac dysfunction. PARP1 inhibition with PJ34 normalized these signaling pathways to sham levels as well as improved cardiac function to sham levels. PARP1 inhibition normalizes multiple inflammatory pathways that are altered after burn injury and improves cardiac dysfunction. PARP1 pathway inhibition may provide a novel methodology to normalize multiple burn injury-induced inflammatory pathways in the heart.

GM3 synthase deficiency increases brain glucose metabolism in mice.

GM3 synthase (GM3S) deficiency is a rare neurodevelopmental disorder caused by an inability to synthesize gangliosides, for which there is currently no treatment. Gangliosides are brain-enriched, plasma membrane glycosphingolipids with poorly understood biological functions related to cell adhesion, growth, and receptor-mediated signal transduction. Here, we investigated the effects of GM3S deficiency on metabolism and mitochondrial function in a mouse model. By indirect calorimetry, GM3S knockout mice exhibited increased whole-body respiration and an increased reliance upon carbohydrate as an energy source. 18F-FDG PET confirmed higher brain glucose uptake in knockout mice, and GM3S deficient N41 neuronal cells showed higher glucose utilization in vitro. Brain mitochondria from knockout mice respired at a higher rate on Complex I substrates including pyruvate. This appeared to be due to higher expression of pyruvate dehydrogenase (PDH) and lower phosphorylation of PDH, which would favor pyruvate entry into the mitochondrial TCA cycle. Finally, it was observed that blocking glucose metabolism with the glycolysis inhibitor 2-deoxyglucose reduced seizure intensity in GM3S knockout mice following administration of kainate. In conclusion, GM3S deficiency may be associated with a hypermetabolic phenotype that could promote seizure activity.

Catabolic reprogramming of Brassica rapa leaf mesophyll protoplasts during the isolation procedure

The use of leaf mesophyll protoplasts for transformation and genome editing in plants is expected due to the distinctive features of protoplasts, such as cell-wall-free single cells. However, the application of leaf mesophyll protoplasts for molecular breeding is limited because of the recalcitrance of protoplasts to regenerate. We speculated that the primary reason for this recalcitrance is senescence during protoplast isolation before initialization. In this study, we performed profiling, clustering, co-expression analysis, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of primary metabolites and transcriptomes of Brassica rapa leaves and leaf mesophyll protoplasts to reveal the reason for senescence. Primary metabolite profiling indicated that the metabolism of B. rapa protoplasts was converted to catabolism. The number of downregulated differentially expressed genes (DEGs) increased during protoplast isolation. An analysis of GO overexpression revealed the activation of genes involved in catabolic and immune system processes and the inactivation of chloroplasts and photosynthetic genes. KEGG pathway analysis showed that the activation of autophagy and proteasomes accounted for senescence-associated proteolysis during protoplast isolation. It also revealed activation of the genes involved in endoplasmic reticulum stress responses and disease resistance responses during the first 3 h of isolation. These results suggest that elicitor receptor-mediated signal transduction stimulates the pathogen-associated molecular patterns (PAMPs), which triggers immunity. There were more downregulated than upregulated transcription factors during protoplast isolation. AT5G39610 (ANAC092, ATNAC2) gene expression was significantly activated throughout the entire period of protoplast isolation. ANAC092 was co-expressed with upregulated AT5G26340 (STP13), which encodes a protein with high affinity, hexose-specific/H + symporter. AT1G50030 encodes target of rapamycin (TOR) proteins, and the expression of TOR decreased during protoplast isolation. The presence of ethylene and the inhibition of photosynthesis-related genes by glucose and sucrose promote senescence-associated gene expression of protoplasts. Since a decrease in glucose downregulates glucose TOR signaling, the inactivated TOR signaling will promote catabolic reprogramming, senescence, and autophagy in protoplasts during protoplast isolation. We concluded that the initialization of protoplasts requires the blocking of these complicated crosstalk signaling pathways to prevent the catabolic reprogramming of protoplasts, which will lead the way to new plant breeding techniques.

Could Endogenous Glucocorticoids Influence SARS-CoV-2 Infectivity?

Endogenous glucocorticoids and their synthetic analogues, such as dexamethasone, stimulate receptor-mediated signal transduction mechanisms on target cells. Some of these mechanisms result in beneficial outcomes whereas others are deleterious in the settings of pathogen infections and immunological disorders. Here, we review recent studies by several groups, including our group, showing that glucocorticoids can directly interact with protein components on SARS-CoV-2, the causative agent of COVID-19. We postulate an antiviral defence mechanism by which endogenous glucocorticoids (e.g., cortisol produced in response to SARS-CoV-2 infection) can bind to multiple sites on SARS-CoV-2 surface protein, Spike, inducing conformational alterations in Spike subunit 1 (S1) that inhibit SARS-CoV-2 interaction with the host SARS-CoV-2 receptor, ACE2. We suggest that glucocorticoids-mediated inhibition of S1 interaction with ACE2 may, consequently, affect SARS-CoV-2 infectivity. Further, glucocorticoids interactions with Spike could protect against a broad spectrum of coronaviruses and their variants that utilize Spike for infection of the host. These notions may be useful for the design of new antivirals for coronavirus diseases.

Janus Kinase 3 phosphorylation and the JAK/STAT pathway are positively modulated by follicle‐stimulating hormone (FSH) in bovine granulosa cells

Janus kinase 3 (JAK3) is a member of the JAK family of tyrosine kinase proteins involved in cytokine receptor‐mediated intracellular signal transduction through the JAK/STAT signaling pathway. JAK3 was shown as differentially expressed in granulosa cells (GC) of bovine preovulatory follicles and downregulated by the luteinizing hormone. These observations suggested JAK3 regulation could modulate GC proliferation, steroidogenic activity and activation/inhibition of downstream targets. To investigate the mechanisms of JAK3 actions in GC, we used JANEX‐1, a pharmacological JAK3 inhibitor, and FSH treatments and analyzed proliferation markers, steroidogenic enzymes and phosphorylation of target proteins including STAT3 and previously identified JAK3 partners CDKN1B/p27Kip1 and MAPK8IP3/JIP3. Cultured GCs were treated with or without FSH in the presence or not of JANEX‐1. Total RNA and proteins were extracted and analyzed by RT‐qPCR, western blotting and UHPLC/MS‐MS. Expression of steroidogenic enzyme CYP11A1, but not CYP19A1, was significantly upregulated in GC treated with FSH and both were significantly decreased when JAK3 was inhibited as compared to control. Proliferation markers CCND2 and PCNA were significantly reduced in JANEX‐1‐treated GC and upregulated by FSH. Western blots analyses showed that JANEX‐1 treatment significantly reduced pSTAT3 amounts while JAK3 overexpression increased pSTAT3. Similarly, FSH treatment increased pSTAT3 even in JANEX‐1‐treated GC. UHPLC/MS‐MS analyses showed phosphorylation and additional modifications of specific amino acid residues within JAK3 as well as its binding partners CDKN1B and MAPK8IP3 revealing possible activation or inhibition of JAK3 following FSH or JANEX‐1 treatments, respectively. Abundance of JAK3 total protein was increased post‐FSH treatment and significantly decreased, along with MAPK8IP3, in JANEX‐1‐treated GC while CDKN1B total abundance was altered post‐FSH and increased post‐JANEX‐1. We show that JAK3 influences GC activity through phosphorylation of target proteins in response to stimulations such as FSH, which leads to the activation of JAK/STAT and likely modulating other signaling pathways involving CDKN1B and MAPK8IP3.

Urticarial drug eruption following tocilizumab administration

Tocilizumab is a humanized anti-IL-6 receptor antibody that exerts its immunosuppressive effect by blocking IL-6 receptor-mediated signal transduction and shows therapeutic anti-inflammatory action in autoimmune diseases. On the contrary, several cutaneous adverse reactions have been reported in patients treated with tocilizumab administration. Herein, we report a case of urticarial drug eruption following tocilizumab administration. Interleukin 6 (IL-6) plays a vital role in the pathogenesis of various inflammatory diseases, especially rheumatoid arthritis.1 Tocilizumab is a humanized anti-IL-6 receptor antibody that exerts its immunosuppressive effect by blocking IL-6 receptor-mediated signal transduction2, 3 and shows therapeutic anti-inflammatory action in autoimmune diseases. On the contrary, several cutaneous adverse reactions have been reported in patients treated with tocilizumab administration.4 Herein, we report a case of urticarial drug eruption following tocilizumab administration. A 50-year-old woman had developed rheumatoid arthritis 5 years ago and was treated with methotrexate and certolizumab. She had no history of urticaria. Because her arthritis was intractable by these treatments, tocilizumab was administrated. One month after the repeated tocilizumab administration, she recognized urticarial eruption in trunk and extremities after the second-time administration of tocilizumab (Figure 1). Her eruption occurred in several hours and disappeared within 24 h after the tocilizumab administration. Her eruption continued to repeat the occurrence of urticaria following repeated tocilizumab administration. Blood examination showed that eosinophil frequency in peripheral blood (11.9%) and IgE-RAST (443 U/ml) were elevated, while the white blood cell count (6,000/μl) and CRP (0.04 mg/dl) were within normal ranges. Although an anti-histamine agent showed less response to her eruption, her urticaria completely diminished after switching into certolizumab without the recurrence of her eruption. Tocilizumab was administrated in total 12 times before switching into certolizumab. Because her urticaria was reproducible following every tocilizumab administration recognized as a positive reaction to challenge test, we diagnosed her skin eruption as urticaria following tocilizumab administration. Tocilizumab shows various cutaneous adverse reactions, and the majority of these cases are type IV delayed hypersensitivity reactions. However, this case showed an unusual clinical manifestation of type I allergic reaction. As a reason to cause urticarial eruption, we thought there were several possibilities. The first one is an immune response to additives in this drug. Tocilizumab contains polysorbate 80, which is a synthetic nonionic surfactant and is used in various medications. Polysorbate 80 is also known as one of the representative agents to cause type I allergic reactions.5 Indeed, polysorbate 80 containing medication induces urticaria.6 Although allergic skin test could be conducted in our case, it should be kept in mind a possibility to cause the same skin eruption following polysorbate 80 containing biologic agents. The second one is a pharmacological effect of tocilizumab mediated by the IL-6 blocking pathway. However, IL-6 increases in various types of urticaria,7 suggesting that a pharmacological effect of tocilizumab mediated by the IL-6 blocking pathway might not contribute to the development of urticaria. As another possibility, tocilizumab might become a trigger to produce tocilizumab-specific anti-IgE production and contribute to the development of urticaria. Since there is no case report of urticaria responding to biologics itself, a further case study is expected to conclude the possibility. The authors declare no conflicts of interest. Approval of the research protocol: No. Informed Consent: N/A. Registry and the Registration: N/A. Animal Studies: N/A.

Preservation of Adrenoceptor and Endothelin Receptor Mediated Vasoconstriction and of Endothelium-Dependent Relaxation after Cold Storage of Explanted Blood Vessels for ex vivo Analyses.

Adrenoceptor and endothelin (ET) receptor-mediated vasoconstriction as well as endothelium-dependent vasodilation of human saphenous veins were compared before and after 20 h of cold storage. Contractile responses to potassium chloride (KCl), norepinephrine (NE), and ET-1 as well as vasodilator responses to acetylcholine (ACh) were evaluated. Storage in HEPES-supplemented Dulbecco's modified Eagle's medium (HDMEM) diminished KCl induced contractile forces to 71% (p = 0.002) and NE induced contractions to 80% (p = 0.037), in contrast to HEPES-supplemented Krebs-Henseleit solution (HKH) and TiProtec solution. KCl-normalized NE contractions were not affected by storage. NE EC50 values were slightly lower (7.1E-8 vs. 7.5E-8, p = 0.019) after storage in HKH, with no changes after storage in the other solutions. Endothelium-dependent responses to ACh were not affected by storage. ET-1 induced contractions were attenuated after storage in HDMEM (77%, p = 0.002), HKH (75%, p = 0.020), and TiProtec (73%, p = 0.010) with no changes in normalized constrictions. ET-1 EC50 values were not affected by storage. Loss of contractility after storage in HDMEM may reflect the lower content of dextrose. There was no specific attenuation of adrenoceptor, ET-receptor, or ACh receptor mediated signal transduction after storage in any of the media. HKH or TiProtec are equally suitable cold storage solutions for ex vivo measurements.

Artesunate-induced Cellular Effects Are Mediated by Specific EPH Receptors and Ephrin Ligands in Breast Carcinoma Cells

The aberrant regulation of erythropoietin-producing hepatocellular carcinoma (EPH) receptors and ephrin ligands has been implicated in breast carcinoma, and artesunate has been shown to have anticancer effects. The aim of this study was to characterize the involvement of EPH receptors and ephrin ligands in mediating artesunate (ART)-induced growth suppression of normal breast cells and breast carcinoma cell lines. The normal breast epithelial cells (MCF10A), non-invasive ductal breast carcinoma cells (MCF7), and invasive triple-negative breast carcinoma cells (MDA-MB-231) were grown in the absence or the presence of different concentrations of artesunate. The cells were counted, and total RNA was isolated. The abundance of transcripts corresponding to EPH receptors and ephrin ligands was determined by quantitative polymerase chain reaction. Cell viability was significantly reduced when cells were treated with artesunate, with MDA-MB-231 cells having the highest sensitivity. Artesunate had no significant effect on transcription of EPH/ephrins in MCF10A cells, but markedly increased EPHA8, EPHA10, EPHB6 and ephrin-A2 expression in MCF7 cells, and significantly increased EPHA3 and EPHA10 expression while reducing that of EPHA7 and ephrin-A3 in MDA-MB-231 cells. The relative changes in artesunate-treated MCF7 and MDA-MB-231 cells as compared to similarly treated MCF10A cells allow us to implicate combinatorial expression and receptor interactions for EPH receptor-mediated signal transduction that converges into pathways responsible for cell growth, proliferation, and apoptosis. Specifically, the alterations in EPHA7, EPHA8, EPHA10 and EPHB6 transcripts appear to be important participants in artesunate-mediated cellular effects.

The Role of Decorin and Biglycan Signaling in Tumorigenesis.

The complex and adaptive nature of malignant neoplasm constitute a major challenge for the development of effective anti-oncogenic therapies. Emerging evidence has uncovered the pivotal functions exerted by the small leucine-rich proteoglycans, decorin and biglycan, in affecting tumor growth and progression. In their soluble forms, decorin and biglycan act as powerful signaling molecules. By receptor-mediated signal transduction, both proteoglycans modulate key processes vital for tumor initiation and progression, such as autophagy, inflammation, cell-cycle, apoptosis, and angiogenesis. Despite of their structural homology, these two proteoglycans interact with distinct cell surface receptors and thus modulate distinct signaling pathways that ultimately affect cancer development. In this review, we summarize growing evidence for the complex roles of decorin and biglycan signaling in tumor biology and address potential novel therapeutic implications.

G3BPs in Plant Stress.

The sessile nature of plants enforces highly adaptable strategies to adapt to different environmental stresses. Plants respond to these stresses by a massive reprogramming of mRNA metabolism. Balancing of mRNA fates, including translation, sequestration, and decay is essential for plants to not only coordinate growth and development but also to combat biotic and abiotic environmental stresses. RNA stress granules (SGs) and processing bodies (P bodies) synchronize mRNA metabolism for optimum functioning of an organism. SGs are evolutionarily conserved cytoplasmic localized RNA-protein storage sites that are formed in response to adverse conditions, harboring mostly but not always translationally inactive mRNAs. SGs disassemble and release mRNAs into a translationally active form upon stress relief. RasGAP SH3 domain binding proteins (G3BPs or Rasputins) are “scaffolds” for the assembly and stability of SGs, which coordinate receptor mediated signal transduction with RNA metabolism. The role of G3BPs in the formation of SGs is well established in mammals, but G3BPs in plants are poorly characterized. In this review, we discuss recent findings of the dynamics and functions of plant G3BPs in response to environmental stresses and speculate on possible mechanisms such as transcription and post-translational modifications that might regulate the function of this important family of proteins.