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peptide science.

Blockade of RANKL/RANK signaling pathway by epigallocatechin gallate alleviates mast cell-mediated inflammatory reactions.

Int Immunopharmacol

Hee-Yun Kim, Ho-Geun Kang, Sun-Young Nam +2 more

Receptor activator of NF-κB ligand (RANKL) as an osteoclast differentiation factor induces inflammatory reactions via production of thymic stromal lymphopoietin (TSLP). Epigallocatechin gallate (EGCG) is the major and the most active compound in green tea and has anti-inflammatory, anti-cancer, anti-oxidant, and neuroprotective effects. However, the effect and molecular mechanisms of EGCG are still unknown in RANKL-induced inflammatory reactions. Here we investigated the immuno-regulatory effects and its molecular mechanisms of epigallocatechin gallate (EGCG) in RANKL-stimulated human mast cell line, HMC-1 cells. In this study, EGCG prevented expression of PI3 Kinase and phosphorylation of mitogen-activated protein (MAP) Kinases in RANKL-stimulated HMC-1 cells. EGCG prevented caspase-1 activity and decreased transcriptional activity of nuclear factor (NF)-κB by suppressing inhibitory protein κBα phosphorylation in RANKL-stimulated HMC-1 cells. EGCG has been shown to prevent production and mRNA expression of TSLP, interleukin (IL)-1β, IL-6, and IL-8 by RANKL without cytotoxicity. Furthermore, EGCG prevented degranulation of mast cell in RANKL-stimulated HMC-1 cells. Overall, these results suggest that EGCG acts as a natural agent for preventing and treating RANKL-mediated inflammatory diseases by targeting PI3 Kinase, MAP Kinase, caspase-1, and NF-κB signaling cascade in mast cells.

Evaluation of Elafin Immunohistochemical Expression as Marker of Cervical Cancer Severity.

Acta Cytol

Adhemar Longatto-Filho, José Humberto Fregnani, Allini Mafra da Costa +5 more

The main risk factor for the development of cervical cancer (CC) is persistent infection by human papillomavirus (HPV) oncogenic types. In order to persist, HPV exhibits a plethora of immune evasion mechanisms. PI3/Elafin (Peptidase Inhibitor 3) is an endogenous serine protease inhibitor involved in epithelial protection against pathogens. PI3/Elafin's role in CC is still poorly understood.

Effects of immunopotentiators on biochemical parameters, proinflammatory cytokine, and nonspecific immune responses in Shaoxing ducklings.

Poult Sci

Tiantian Gu, Guoqin Li, Xinsheng Wu +6 more

Antibiotics are one of the most important medical discoveries of the 20th century and will remain an essential tool for treating animal and human diseases in the 21st century. However, misuse of antibiotics imperils the development of animal husbandry and human health all over the world, and it is important to find reliable alternatives to antibiotics to reduce the use of antibiotics. In this study, 22 potential immunopotentiators were screened on the levels of apoptosis and inflammatory factor in duck embryo fibroblast cells (DEFs). The results indicated that interferon (IFN)-β and tumor necrosis factor-α gene transcriptions were significantly upregulated, while interleukin (IL)-2 and Bcl2 mRNA levels were significantly decreased during 22 immunopotentiators treatment. Besides, the expression level of IL-1β mRNA showed significant increase during dihydromyricetin, chlorogenic acid, naringin, imiquimod, thymopentin, β-D-Glucan, astragalus polysacharin, astragalus saponin I, astragalus flavone, curcumin, CpG-DNA-2, and LPS treatment. And the level of caspase 3 protein was significantly upregulated with treating chlorogenic acid, β-D-Glucan, astragalus polysacharin, astragalus flavone, curcumin, CpG-DNA-2, chicken IgG, LPS, and poly(I:C). These results indicated that chlorogenic acid, β-D-Glucan, astragalus flavone, CpG-DNA-2, and chicken IgG have the positive immune regulation effects on duck DEFs. Thus, the 5 immunopotentiators were chosen to further verify their immunomodulatory function in vivo. The results showed that the activity of serum AST was significantly downregulated during all immunopotentiators treatments excepting for β-D-Glucan, and the activities of serum IL12p40, IL-1β, IFN-α, and IFN-β were significantly increased compared with the control group. Five immunopotentiators also induced the duck's pattern recognition receptors and inflammatory factor gene expression. In addition, 5 immunopotentiators could facilitate the contents of serum caspase 3, iNOSm and COX2 and reduce the Bcl2. These results suggested that these 5 immunopotentiators could enhance duck innate immune responses. Taken together, our study not only screened out 5 kinds of duck innate immune immunopotentiators but also initially clarified their underlying mechanism of action, which provide a new insight for the development of efficient approaches to prevent the duck disease from pathogen infections.

Vasopressin and post-traumatic stress disorder.

Stress

Eszter Sipos, Bibiána Török, István Barna +2 more

Post-traumatic stress disorder (PTSD) is a debilitating psychiatric condition with a wide range of behavioral disturbances and serious consequences for both patient and society. One of the main reasons for unsuccessful therapies is insufficient knowledge about its underlying pathomechanism. In the search for centrally signaling molecules that might be relevant to the development of PTSD we focus here on arginine vasopressin (AVP). So far AVP has not been strongly implicated in PTSD, but different lines of evidence suggest a possible impact of its signaling in all clusters of PTSD symptomatology. More specifically, in laboratory rodents, AVP agonists affect behavior in a PTSD-like manner, while significant reduction of AVP signaling in the brain e.g. in AVP-deficient Brattleboro rats, ameliorated defined behavioral parameters that can be linked to PTSD symptoms. Different animal models of PTSD also show alterations in the AVP signaling in distinct brain areas. However, pharmacological treatment targeting central AVP receptors via systemic routes is hampered by possible side effects that are linked to the peripheral action of AVP as a hormone. Indeed, the V1a receptor, the most common receptor subtype in the brain, is implicated in vasoconstriction. Thus, systemic treatment with V1a receptor antagonists would be implicated in hypotonia. This implies that novel treatment concepts are needed to target AVP receptors not only at brain level but also in distinct brain areas, to offer alternative treatments for PTSD.

Thymopentin improves the survival of septic mice by promoting the production of 15-deoxy-prostaglandin J2 and activating the PPARγ signaling pathway.

FASEB J

Ye Zhang, Xue Yang, Wenchao Yan +13 more

Sepsis, a systemic inflammatory response syndrome (SIRS) caused by infection, is a major public health concern with limited therapeutic options. Infection disturbs the homeostasis of host, resulting in excessive inflammation and immune suppression. This has prompted the clinical use of immunomodulators to balance host response as an alternative therapeutic strategy. Here, we report that Thymopentin (TP5), a synthetic immunomodulator pentapeptide (Arg-Lys-Asp-Val-Tyr) with an excellent safety profile in the clinic, protects mice against cecal ligation and puncture (CLP)-induced sepsis, as shown by improved survival rate, decreased level of pro-inflammatory cytokines and reduced ratios of macrophages and neutrophils in spleen and peritoneum. Regarding mechanism, TP5 changed the characteristics of LPS-stimulated macrophages by increasing the production of 15-deoxy-Δ12,14 -prostaglandin J2 (15-d-PGJ2). In addition, the improved effect of TP5 on survival rates was abolished by the peroxisome proliferator-activated receptor γ (PPARγ) antagonist GW9662. Our results uncover the mechanism of the TP5 protective effects on CLP-induced sepsis and shed light on the development of TP5 as a therapeutic strategy for lethal systemic inflammatory disorders.

Novel Insights into the Protective Properties of ACTH(4-7)PGP (Semax) Peptide at the Transcriptome Level Following Cerebral Ischaemia-Reperfusion in Rats.

Genes (Basel)

Ivan B Filippenkov, Vasily V Stavchansky, Alina E Denisova +8 more

Cerebral ischaemia is the most common cause of impaired brain function. Biologically active peptides represent potential drugs for reducing the damage that occurs after ischaemia. The synthetic melanocortin derivative, ACTH(4-7)PGP (Semax), has been used successfully in the treatment of patients with severe impairment of cerebral blood circulation. However, its molecular mechanisms of action within the brain are not yet fully understood. Previously, we used the transient middle cerebral artery occlusion (tMCAO) model to study the damaging effects of ischaemia-reperfusion on the brain transcriptome in rats. Here, using RNA-Seq analysis, we investigated the protective properties of the Semax peptide at the transcriptome level under tMCAO conditions. We have identified 394 differentially expressed genes (DEGs) (>1.5-fold change) in the brains of rats at 24 h after tMCAO treated with Semax relative to saline. Following tMCAO, we found that Semax suppressed the expression of genes related to inflammatory processes and activated the expression of genes related to neurotransmission. In contrast, ischaemia-reperfusion alone activated the expression of inflammation-related genes and suppressed the expression of neurotransmission-related genes. Therefore, the neuroprotective action of Semax may be associated with a compensation of mRNA expression patterns that are disrupted during ischaemia-reperfusion conditions.

A role for CIM6P/IGF2 receptor in memory consolidation and enhancement.

Elife

Xiao-Wen Yu, Kiran Pandey, Aaron C Katzman +1 more

Cation-independent mannose-6-phosphate receptor, also called insulin-like growth factor two receptor (CIM6P/IGF2R), plays important roles in growth and development, but is also extensively expressed in the mature nervous system, particularly in the hippocampus, where its functions are largely unknown. One of its major ligands, IGF2, is critical for long-term memory formation and strengthening. Using CIM6P/IGF2R inhibition in rats and neuron-specific knockdown in mice, here we show that hippocampal CIM6P/IGF2R is necessary for hippocampus-dependent memory consolidation, but dispensable for learning, memory retrieval, and reconsolidation. CIM6P/IGF2R controls the training-induced upregulation of de novo protein synthesis, including increase of Arc, Egr1, and c-Fos proteins, without affecting their mRNA induction. Hippocampal or systemic administration of mannose-6-phosphate, like IGF2, significantly enhances memory retention and persistence in a CIM6P/IGF2R-dependent manner. Thus, hippocampal CIM6P/IGF2R plays a critical role in memory consolidation by controlling the rate of training-regulated protein metabolism and is also a target mechanism for memory enhancement.

Influenza A Virus Pre-Infection Exacerbates Pseudomonas aeruginosa-Mediated Lung Damage Through Increased MMP-9 Expression, Decreased Elafin Production and Tissue Resilience.

Front Immunol

Berengère Villeret, Brigitte Solhonne, Marjolène Straube +4 more

Individuals with impaired immune responses, such as ventilated and cystic fibrosis patients are often infected with Pseudomonas aeruginosa (P.a) bacteria, and a co-infection with the Influenza virus (IAV) is often present. It has been known for many years that infection with IAV predisposes the host to secondary bacterial infections (such as Streptococcus pneumoniae or Staphylococcus aureus), and there is an abundance of mechanistic studies, including those studying the role of desensitization of TLR signaling, type I IFN- mediated impairment of neutrophil chemokines and antimicrobial production, attenuation of IL1β production etc., showing this. However, little is known about the mechanistic events underlying the potential deleterious synergy between Influenza and P.a co-infections. We demonstrate here in vitro in epithelial cells and in vivo in three independent models (two involving mice given IAV +/- P.a, and one involving mice given IAV +/- IL-1β) that IAV promotes secondary P.a-mediated lung disease or augmented IL-1β-mediated inflammation. We show that IAV-P.a-mediated deleterious responses includes increased matrix metalloprotease (MMP) activity, and MMP-9 in particular, and that the use of the MMP inhibitor improves lung resilience. Furthermore, we show that IAV post-transcriptionally inhibits the antimicrobial/anti-protease molecule elafin/trappin-2, which we have shown previously to be anti-inflammatory and to protect the host against maladaptive neutrophilic inflammation in P.a infections. Our work highlights the capacity of IAV to promote further P.a-mediated lung damage, not necessarily through its interference with host resistance to the bacterium, but by down-regulating tissue resilience to lung inflammation instead. Our study therefore suggests that restoring tissue resilience in clinical settings where IAV/P.a co-exists could prove a fruitful strategy.

Cognitive Enhancer Noopept Activates Transcription Factor HIF-1.

Dokl Biochem Biophys

L F Zainullina, T V Ivanova, S V Sadovnikov +2 more

The effect of noopept (N-phenylacetyl-L-prolyl-glycine ethyl ester) on the DNA-binding activity of HIF-1 in SH-SH5Y cells and the mechanisms of stabilization of this transcription factor were studied in vitro. Noopept was shown to increase both the basal DNA-binding activity of HIF-1 and the activity induced by various hypoxia mimetics. The mechanism of stabilization of the oxygen-sensitive HIF1α subunit by noopept involves the inhibition of HIF-1 prolyl hydroxylase, which is indirectly indicated by the data obtained using the ODD-Luc reporter, and the positive effect on the level of the HIF1α protein. It was revealed that the effect of noopept is accompanied by changes in gene expression, which belong to different metabolic pathways and are controlled by the transcription factor HIF-1.

GHRH Antagonists Protect Against Hydrogen Peroxide-Induced Breakdown of Brain Microvascular Endothelium Integrity.

Horm Metab Res

Nektarios Barabutis, Mohammad S Akhter, Mohammad A Uddin +2 more

Growth hormone releasing hormone is a hypothalamic neuropeptide, which regulates the release of growth hormone from the anterior pituitary gland. Growth hormone releasing hormone antagonists are anticancer agents, associated with strong anti-inflammatory activities. In the present study, we investigated the effects of the GHRH antagonist MIA-602 in the integrity of the brain microvascular endothelium in vitro. Our observations suggest that MIA-602 protects against the H2O2-induced breakdown of the brain endothelium and enhances its integrity by inducing P53, deactivating cofilin, and suppressing the RhoA inflammatory pathway. Thus, GHRH antagonists may offer an exciting possibility for the treatment of pathologies related to the blood brain barrier dysfunction, including the Parkinson's and Alzheimer's diseases.

Functional Connectomic Approach to Studying Selank and Semax Effects.

Dokl Biol Sci

Ya R Panikratova, I S Lebedeva, O Yu Sokolov +4 more

The present study was aimed at the assessment of effects of anxiolytic Selank and nootropic Semax on the whole-brain resting-state functional connectivity (FC) of each of the predefined regions of interest (ROIs) in 52 healthy participants. The ROIs included amygdala (one of the key regions for the regulation of anxiety) and dorsolateral prefrontal cortex (DLPFC; the key region for executive functions, including working memory) in the right and left hemisphere. Resting-state fMRI was carried out three times, namely before, after 5 and 20 min of the injection of either Semax, or Selank, or placebo. Between-group alongwith between-condition differences were revealed in FC between the right amygdala and a region in fusiform, inferior and middle temporal as well as parahippocampal gyri in the right hemisphere. Post hoc analysis allowed us to define both general and specific effects of Selank and Semax on FC between the right amygdala and the right temporal cortex for the first time.

Ternary Cu(II) Complex with GHK Peptide and Cis-Urocanic Acid as a Potential Physiologically Functional Copper Chelate.

Int J Mol Sci

Karolina Bossak-Ahmad, Marta D Wiśniewska, Wojciech Bal +2 more

The tripeptide NH2-Gly-His-Lys-COOH (GHK), cis-urocanic acid (cis-UCA) and Cu(II) ions are physiological constituents of the human body and they co-occur (e.g., in the skin and the plasma). While GHK is known as Cu(II)-binding molecule, we found that urocanic acid also coordinates Cu(II) ions. Furthermore, both ligands create ternary Cu(II) complex being probably physiologically functional species. Regarding the natural concentrations of the studied molecules in some human tissues, together with the affinities reported here, we conclude that the ternary complex [GHK][Cu(II)][cis-urocanic acid] may be partly responsible for biological effects of GHK and urocanic acid described in the literature.

Unilateral orolingual angioedema in a patient with sarcoidosis after intravenous thrombolysis due to acute stroke without improvement after treatment with icatibant.

BMJ Case Rep

Anna Daniela Wollmach, Daniel Zehnder, Markus Schwendinger +1 more

A potential complication after intravenous administration of recombinant tissue plasminogen activators (rtPAs) for thrombolysis in acute ischaemic stroke is orolingual angioedema, with an incidence of 0.4%-7.9%. In the herewith reported case, we discuss potential links between a history of sarcoidosis and the occurrence of orolingual angioedema after rtPA administration. Sarcoidosis is often accompanied by an elevated ACE level. In contrast, low ACE levels appear to play a role in the pathomechanism currently assumed to trigger angioedema, that is, the activation of the bradykinin and complement pathways. Medication with ACE inhibitors is considered a risk factor for angioedema. Based on these considerations, the patient was also treated with icatibant, a bradykinin B2-receptor antagonist, which has been found useful in recent publications on treating orolingual angioedema after intravenous lysis in ischaemic stroke.

Metabolic Syndrome, Clusterin and Elafin in Patients with Psoriasis Vulgaris.

Int J Mol Sci

Drahomira Holmannova, Pavel Borsky, Lenka Borska +9 more

Psoriasis is a pathological condition characterized by immune system dysfunction and inflammation. Patients with psoriasis are more likely to develop a wide range of disorders associated with inflammation. Serum levels of various substances and their combinations have been associated with the presence of the disease (psoriasis) and have shown the potential to reflect its activity. The aim of the present study is to contribute to the elucidation of pathophysiological links between psoriasis, its pro-inflammatory comorbidity metabolic syndrome (MetS), and the expression of clusterin and elafin, which are reflected in the pathophysiological "portfolio" of both diseases.

Myostatin inhibition promotes fast fibre hypertrophy but causes loss of AMP-activated protein kinase signalling and poor exercise tolerance in a model of limb-girdle muscular dystrophy R1/2A.

J Physiol

Irina Kramerova, Masha Marinov, Jane Owens +3 more

Limb-girdle muscular dystrophy R1 (LGMD R1) is caused by mutations in the CAPN3 gene and is characterized by progressive muscle loss, impaired mitochondrial function and reductions in the slow oxidative gene expression programme. Myostatin is a negative regulator of muscle growth, and its inhibition improves the phenotype in several muscle wasting disorders. The effect of genetic and pharmacological inhibition of myostatin signalling on the disease phenotype in a mouse model of LGMD R1 (CAPN3 knockout mouse-C3KO) was studied. Inhibition of myostatin signalling in C3KO muscles resulted in significant muscle hypertrophy; however, there were no improvements in muscle strength and exacerbation of exercise intolerance concomitant with further reduction of muscle oxidative capacity was observed. Inhibition of myostatin signalling is unlikely to be a valid therapeutic strategy for LGMD R1.

Correction of Lipid Metabolism Disorders in Diabetes Mellitus with Peptide Drugs.

Bull Exp Biol Med

A A Elagina, Yu D Lyashev, A Yu Lyashev +2 more

We studied the effect of peptide drugs deltalicin and Semax on lipid metabolism disturbances in diabetes mellitus. Diabetes mellitus was modeled by single injection of streptozotocin (45 mg/kg) and rats with blood glucose ≥12 mmol/liter were selected for the further experiments. Deltalicin in a dose 100 μg/kg and Semax in a dose 200 μg/kg as well as sulodexide corrected lipid metabolism disorders: the content of total cholesterol, triglycerides, LDL, index of atherogenicity decreased and HDL concentration increased. Deltalicin produced more potent effect on lipid metabolism in rats with diabetes mellitus than sulodexide and Semax, which manifested in a significant decrease in total cholesterol and LDL concentration and index of atherogenicity.

Qualitative and Quantitative Changes to Escherichia coli during Treatment with Magainin 2 Observed in Native Conditions by Atomic Force Microscopy.

Langmuir

Kanesha Overton, Helen M Greer, Megan A Ferguson +4 more

The bacterial membrane has been suggested as a good target for future antibiotics, so it is important to understand how naturally occurring antibiotics like antimicrobial peptides (AMPs) disrupt those membranes. The interaction of the AMP magainin 2 (MAG2) with the bacterial cell membrane has been well characterized using supported lipid substrates, unilamellar vesicles, and spheroplasts created from bacterial cells. However, to fully understand how MAG2 kills bacteria, we must consider its effect on the outer membrane found in Gram-negative bacteria. Here, we use atomic force microscopy (AFM) to directly investigate MAG2 interaction with the outer membrane of Escherichia coli and characterize the biophysical consequences of MAG2 treatment under native conditions. While propidium iodide penetration indicates that MAG2 permeabilizes cells within seconds, a corresponding decrease in cellular turgor pressure is not observed until minutes after MAG2 application, suggesting that cellular homeostasis machinery may be responsible for helping the cell maintain turgor pressure despite a loss of membrane integrity. AFM imaging and force measurement modes applied in tandem reveal that the outer membrane becomes pitted, more flexible, and more adhesive after MAG2 treatment. MAG2 appears to have a highly disruptive effect on the outer membrane, extending the known mechanism of MAG2 to the Gram-negative outer membrane.

Deciphering the Enigma: NAP (CP201) the Active ADNP Drug Candidate Enters Cells by Dynamin-Associated Endocytosis.

J Mol Neurosci

Yanina Ivashko-Pachima, Illana Gozes

Fully automated dried blood spot sample preparation enables the detection of lower molecular mass peptide and non-peptide doping agents by means of LC-HRMS.

Anal Bioanal Chem

Tobias Lange, Andreas Thomas, Katja Walpurgis +1 more

The added value of dried blood spot (DBS) samples complementing the information obtained from commonly routine doping control matrices is continuously increasing in sports drug testing. In this project, a robotic-assisted non-destructive hematocrit measurement from dried blood spots by near-infrared spectroscopy followed by a fully automated sample preparation including strong cation exchange solid-phase extraction and evaporation enabled the detection of 46 lower molecular mass (< 2 kDa) peptide and non-peptide drugs and drug candidates by means of LC-HRMS. The target analytes included, amongst others, agonists of the gonadotropin-releasing hormone receptor, the ghrelin receptor, the human growth hormone receptor, and the antidiuretic hormone receptor. Furthermore, several glycine derivatives of growth hormone-releasing peptides (GHRPs), arguably designed to undermine current anti-doping testing approaches, were implemented to the presented detection method. The initial testing assay was validated according to the World Anti-Doping Agency guidelines with estimated LODs between 0.5 and 20 ng/mL. As a proof of concept, authentic post-administration specimens containing GHRP-2 and GHRP-6 were successfully analyzed. Furthermore, DBS obtained from a sampling device operating with microneedles for blood collection from the upper arm were analyzed and the matrix was cross-validated for selected parameters. The introduction of the hematocrit measurement method can be of great value for doping analysis as it allows for quantitative DBS applications by managing the well-recognized "hematocrit effect." Graphical abstract.

AMP-activated protein kinase (AMPK) signaling in GnRH neurons links energy status and reproduction.

Metabolism

D Franssen, A Barroso, F Ruiz-Pino +12 more

Reproduction is tightly coupled to body energy and metabolic status. GnRH neurons, master elements and final output pathway for the brain control of reproduction, directly or indirectly receive and integrate multiple metabolic cues to regulate reproductive function. Yet, the molecular underpinnings of such phenomenon remain largely unfolded. AMP-activated protein kinase (AMPK), the fundamental cellular sensor that becomes activated in conditions of energy deficit, has been recently shown to participate in the control of Kiss1 neurons, essential gatekeepers of the reproductive axis, by driving an inhibitory valence in situations of energy scarcity at puberty. However, the contribution of AMPK signaling specifically in GnRH neurons to the metabolic control of reproduction remains unknown.