scholarly journals Prostacyclin signaling regulates circulating ghrelin during acute inflammation

2007 ◽  
Vol 196 (2) ◽  
pp. 263-273 ◽  
Author(s):  
Lisa D Madison ◽  
Jarrad M Scarlett ◽  
Peter Levasseur ◽  
XinXia Zhu ◽  
Kenneth Newcomb ◽  
...  

Ghrelin is an octanoylated 28 amino acid peptide predominantly secreted by the stomach, and has potent stimulatory effects on appetite. Several laboratories, including our own, have demonstrated that ghrelin levels fall in states of acute inflammation brought about by injection of bacterial lipopolysaccharide (LPS). We now demonstrate that the decrease in circulating ghrelin is not due to a decrease in ghrelin gene expression, but is instead likely to be due to an acute decrease in ghrelin secretion. Furthermore, we have found that the change in circulating ghrelin during acute inflammation required a prostaglandin second messenger, but did not require the synthesis of nitric oxide. Interestingly, i.v. injection of prostaglandin E2 failed to decrease circulating ghrelin levels, whereas prostacyclin decreased circulating ghrelin to a similar extent as did LPS. We also provide anatomical evidence for the mechanism of the regulation of ghrelin by inflammation. We demonstrate that the type 1 interleukin-1β (IL-1β) receptor is expressed within the gastric mucosa, but is not expressed by ghrelin cells. The prostacyclin receptor was also expressed in the gastric mucosa, and the majority of ghrelin-producing cells were found to co-express this receptor. Mice with genetic deletion of the type 1 IL-1 receptor do not suppress circulating ghrelin levels with LPS administration. Collectively, these data support a model in which the mechanism of inflammation induced decreases in ghrelin are due to the action of IL-1β on cells within the gastric mucosa that in turn produce prostacyclin as a second messenger. These data provide further support for the potential role of ghrelin as a therapeutic agent in acute and chronic inflammatory diseases.

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Mi Jeong Jo ◽  
Jong Rok Lee ◽  
Il Je Cho ◽  
Young Woo Kim ◽  
Sang Chan Kim

Erigeron annuusis a naturalized plant belonging to Compositae (asteraceae) family, which is called the annual fleabane, and commonly found at meadows and roadside. This study investigated the anti-inflammatory effects of the extract ofE. annuusroots (EER), as assessed by the paw edema formation and histological analysis in rat, and the productions of nitric oxide (NO), prostaglandin E2(PGE2), and pro-inflammatory cytokines in Raw264.7 murine macrophages. Carrageenan treatment promoted infiltration of inflammatory cells and caused swelling in the hind paw. Oral administrations of EER (0.3 g/kg and 1 g/kg) attenuated acute inflammation similar to the result using dexamethasone (1 mg/kg). Treatment of macrophages with lipopolysaccharide (LPS) simulated inflammatory condition: LPS significantly increased the productions of NO, PGE2, and proinflammatory cytokines. EER suppressed activation of macrophages, preventing the induction of iNOS and COX-2 protein expressions. LPS treatment induced phosphorylation of I-κBαand increased the level of nuclear NF-κB protein, both of which were suppressed by concomitant treatment of EER. In conclusion, EER ameliorated acute inflammation in rats, and the induction of NO, PGE2, and proinflammatory cytokines in Raw264.7 cells. EER’s effects may be associated with its inhibition of NF-κB activation, suggesting its effect on inflammatory diseases.


2021 ◽  
Vol 9 (2) ◽  
pp. 292
Author(s):  
Miroslava Šudomová ◽  
Sherif T. S. Hassan

Herpesviruses are DNA viruses that infect humans and animals with the ability to induce latent and lytic infections in their hosts, causing critical health complications. The enrolment of nutraceutical anti-herpesvirus drugs in clinical investigations with promising levels of reduced resistance, free or minimal cellular toxicity, and diverse mechanisms of action might be an effective way to defeat challenges that hurdle the progress of anti-herpesvirus drug development, including the problems with drug resistance and recurrent infections. Therefore, in this review, we aim to hunt down all investigations that feature the curative properties of curcumin, a principal bioactive phenolic compound of the spice turmeric, in regard to various human and animal herpesvirus infections and inflammation connected with these diseases. Curcumin was explored with potent antiherpetic actions against herpes simplex virus type 1 and type 2, human cytomegalovirus, Kaposi’s sarcoma-associated herpesvirus, Epstein–Barr virus, bovine herpesvirus 1, and pseudorabies virus. The mechanisms and pathways by which curcumin inhibits anti-herpesvirus activities by targeting multiple steps in herpesvirus life/infectious cycle are emphasized. Improved strategies to overcome bioavailability challenges that limit its use in clinical practice, along with approaches and new directions to enhance the anti-herpesvirus efficacy of this compound, are also reviewed. According to the reviewed studies, this paper presents curcumin as a promising natural drug for the prevention and treatment of herpesvirus infections and their associated inflammatory diseases.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
M. Geiger ◽  
T. Janes ◽  
H. Keshavarz ◽  
S. Summers ◽  
C. Pinger ◽  
...  

Abstract People with type 1 diabetes (T1D) require exogenous administration of insulin, which stimulates the translocation of the GLUT4 glucose transporter to cell membranes. However, most bloodstream cells contain GLUT1 and are not directly affected by insulin. Here, we report that C-peptide, the 31-amino acid peptide secreted in equal amounts with insulin in vivo, is part of a 3-component complex that affects red blood cell (RBC) membranes. Multiple techniques were used to demonstrate saturable and specific C-peptide binding to RBCs when delivered as part of a complex with albumin. Importantly, when the complex also included Zn2+, a significant increase in cell membrane GLUT1 was measured, thus providing a cellular effect similar to insulin, but on a transporter on which insulin has no effect.


1990 ◽  
Vol 68 (2) ◽  
pp. 207-210 ◽  
Author(s):  
B. L. Tepperman ◽  
B. D. Soper

We have observed that removal of the salivary glands is associated with an increase in the susceptibility to gastric mucosal damage in the rat. In the present study, we have examined the effect of sialoadenectomy on ethanol-induced mucosal hemorrhagic damage and myeloperoxidase (MPO) activity. Hemorrhagic damage and MPO activity in response to intragastric 50% w/v ethanol were greater in sialoadenectomized rats when compared with sham-operated animals. Pretreatment with 16,16-dimethylprostaglandin E2 (0.3 μg/kg s.c.) reduced damage and MPO activity in both sialoadenectomized and sham control rats receiving 50% ethanol. The reduction in these parameters was greater in control than in sialoadenectomized rats. Pretreatment with epidermal growth factor (5 μg/kg s.c.) significantly reduced MPO activity but did not significantly affect the extent of damage. These data suggest that sialoadenectomy is associated with an increase in mucosal inflammation in animals given ethanol. However, in some situations tissue inflammation (as indicated by MPO activity) was reduced, while the proportion of gastric mucosa exhibiting hemorrhagic damage was not changed.Key words: salivary glands, gastric mucosa, neutrophils, prostaglandin E2, epidermal growth factor.


2020 ◽  
Author(s):  
Stephen Antwi ◽  
Daniel Oduro-Mensah ◽  
David Darko Obiri ◽  
Newman Osafo ◽  
Aaron Opoku Antwi ◽  
...  

Abstract Background: Holarrhena floribunda stem bark has anecdotal use in Ghanaian folk medicine for management of inflammatory conditions. This study was conducted to investigate the in vivo anti-inflammatory activity of the bark extract using models of acute inflammation in male Sprague Dawley rats, C57BL/6 mice and 36 ICR mice. Methods: A 70 % hydro-ethanol extract of the stem bark (HFE) was evaluated at doses of 5–500 mg/kg bw. Local anaphylaxis was modelled by the pinnal cutaneous anaphylactic test. Systemic anaphylaxis or sepsis were modeled by compound 48/80 or lipopolysaccharide, respectively. Clonidine-induced catalepsy was used to investigate effect on histamine signaling. Anti-oedematogenic effect was assessed by induction with carrageenan. Effects on mediators of biphasic acute inflammation were studied using histamine and serotonin (early phase) or prostaglandin E2 (late phase).Results: HFE demonstrated anti-inflammatory and/or anti-oedematogenic activity comparable to standard doses of aspirin and diclofenac (inhibitors of cyclooxygenases-1 and -2), chlorpheniramine (histamine H1-receptor antagonist), dexamethasone (glucocorticoid receptor agonist), granisetron (serotonin receptor antagonist) and sodium cromoglycate (inhibitor of mast cell degranulation). All observed HFE bioactivities increased with dose.Conclusions: The data provide evidence that the extract of H. floribunda stem bark has anti-anaphylactic and anti-oedematogenic effects; by interfering with signalling or metabolism of histamine, serotonin and prostaglandin E2 which mediate progression of inflammation. The anti-inflammatory and antihistaminic activities of HFE may be relevant in the context of management of COVID-19.


2021 ◽  
Vol 11 (9) ◽  
pp. 544-549
Author(s):  
Paulina Trojanowska ◽  
Magdalena Chrościńska-Krawczyk ◽  
Alina Trojanowska ◽  
Ewa Tywanek ◽  
Jakub Wronecki ◽  
...  

Understanding the important role of the non-specific immune response in protecting the body against the development of numerous diseases has become partially possible after the discovery of several classes of pattern recognition receptors (PRR), such as Toll-like or NOD-like receptors. A group of cytoplasmic proteins called the inflammasome, which detect PAMP and DAMP through the PRR receptors, is able to activate pro-inflammatory cytokines and trigger an acute inflammatory reaction both in the extracellular and intracellular space. Low-grade systemic and local inflammation contributes to the development and progression of various conditions, including autoimmune and metabolic diseases, such as diabetes, metabolic syndrome and atherosclerosis, which until recently were not even considered inflammatory diseases. This review will discuss the role of innate immunity in the development of type 1 and type 2 diabetes, focusing on the role of specific innate immunity receptors and insulin resistance involved in these diseases pathogenesis.


2018 ◽  
Author(s):  
Maria Pokrovskii ◽  
Jason A. Hall ◽  
David E. Ochayon ◽  
Ren Yi ◽  
Natalia S. Chaimowitz ◽  
...  

SummaryInnate lymphoid cells (ILCs) can be subdivided into several distinct cytokine-secreting lineages that promote tissue homeostasis and immune defense but also contribute to inflammatory diseases. Accumulating evidence suggests that ILCs, similarly to other immune populations, are capable of phenotypic and functional plasticity in response to infectious or environmental stimuli. Yet the transcriptional circuits that control ILC identity and function are largely unknown. Here we integrate gene expression and chromatin accessibility data to infer transcriptional regulatory networks within intestinal type 1, 2, and 3 ILCs. We predict the “core” sets of transcription-factor (TF) regulators driving each ILC subset identity, among which only a few TFs were previously known. To assist in the interpretation of these networks, TFs were organized into cooperative clusters, or modules that control gene programs with distinct functions. The ILC network reveals extensive alternative-lineage-gene repression, whose regulation may explain reported plasticity between ILC subsets. We validate new roles for c-MAF and BCL6 as regulators affecting the type 1 and type 3 ILC lineages. Manipulation of TF pathways identified here might provide a novel means to selectively regulate ILC effector functions to alleviate inflammatory disease or enhance host tolerance to pathogenic microbes or noxious stimuli. Our results will enable further exploration of ILC biology, while our network approach will be broadly applicable to identifying key cell state regulators in otherin vivocell populations.


2007 ◽  
Vol 98 (08) ◽  
pp. 262-273 ◽  
Author(s):  
Jürgen Schymeinsky ◽  
Attila Mócsai ◽  
Barbara Walzog

SummaryPolymorphonuclear neutrophils (PMN) are key components of the innate immunity and their efficient recruitment to the sites of lesion is a prerequisite for acute inflammation. Signaling via adhesion molecules of the β2 integrin family (CD11/CD18) plays an essential role for PMN recruitment and activation during inflammation. In this review, we will focus on the non-receptor tyrosine kinase Syk, an important downstream signaling component of β2 integrins that is required for the control of different PMN functions including adhesion,migration and phagocytosis. The exploration of β2 integrin-mediated Syk activation provided not only novel insights into the control of PMN functions but also led to the identification of Syk as a new molecular target for therapeutic intervention during inflammatory diseases.


Sign in / Sign up

Export Citation Format

Share Document