scholarly journals PPAR-gamma Fun(gi) With Prostaglandin

2020 ◽  
Vol 17 ◽  
pp. 155076291989964
Author(s):  
Robert J. Evans ◽  
Simon A. Johnston

In our recent publication, we show for the first time that the fungal pathogen Cryptococcus neoformans is able to manipulate host cells by producing eicosanoids that mimic those found in the host. Using complementary in vivo zebrafish and in vitro macrophage cell culture models of Cryptococcus infection, we found that these eicosanoids manipulate host innate immune cells by activating the host receptor PPAR-gamma which is an important regulator of macrophage inflammatory phenotypes. We initially identified PGE2 as the eicosanoid species responsible for this effect; however, we later found that a derivative of PGE2—15-keto-PGE2—was ultimately responsible and that this eicosanoid acted as a partial agonist to PPAR-gamma. In this commentary, we will discuss some of the concepts and conclusions in our original publication and expand on their implications and future directions.

2020 ◽  
Author(s):  
María A. Duque-Correa ◽  
David Goulding ◽  
Claire Cormie ◽  
Catherine Sharpe ◽  
Judit Gali Moya ◽  
...  

ABSTRACTHundreds of millions of people are infected with whipworms (Trichuris trichiura), large metazoan parasites that live in the caecum and proximal colon. Whipworms inhabit distinct multi-intracellular epithelial burrows that have been described as syncytial tunnels. However, the interactions between first-stage (L1) larvae and the host epithelia that determine parasite invasion and establishment in the syncytium remain unclear. In vivo experiments investigating these events have been severely hampered by the limited in situ accessibility to intracellular infective larvae at the bottom of the crypts of Lieberkühn, and the lack of genetic tools such as fluorescent organisms that are readily available for other pathogens but not parasitic nematodes. Moreover, cell lines, which do not mimic the complexity of the intestinal epithelium, have been unsuccessful in supporting infection by whipworm larvae. Here, we show that caecaloids grown in an open crypt-like conformation recapitulate the caecal epithelium. Using this system, we establish in vitro infections with T. muris L1 larvae for the first-time, and provide clear evidence that syncytial tunnels are formed at this early stage. We show that larval whipworms are completely intracellular but woven through multiple cells. Using the caecaloids, we are able to visualise the pathways taken by the larvae as they burrow through the epithelial cells. We also demonstrate that larvae degrade the mucus layers overlaying the epithelium, enabling them to access the cells below. We show that early syncytial tunnels are composed of enterocytes and goblet cells that are alive and actively interacting with the larvae during the first 24 h of the infection. Progression of infection results in damage to host cells and by 72 h post-infection, we show that desmosomes of cells from infected epithelium widen and some host cells appear to become liquified. Collectively, our work unravels processes mediating the intestinal epithelium invasion by whipworms and reveals new specific interactions between the host and the parasite that allow the whipworm to establish on its multi-intracellular niche. Our study demonstrates that caecaloids can be used as a relevant in vitro model to investigate the infection biology of T. muris during the early colonisation of its host.


2019 ◽  
Vol 47 (13) ◽  
pp. 7003-7017 ◽  
Author(s):  
Lisa Marie Simon ◽  
Edoardo Morandi ◽  
Anna Luganini ◽  
Giorgio Gribaudo ◽  
Luis Martinez-Sobrido ◽  
...  

AbstractThe influenza A virus (IAV) is a continuous health threat to humans as well as animals due to its recurring epidemics and pandemics. The IAV genome is segmented and the eight negative-sense viral RNAs (vRNAs) are transcribed into positive sense complementary RNAs (cRNAs) and viral messenger RNAs (mRNAs) inside infected host cells. A role for the secondary structure of IAV mRNAs has been hypothesized and debated for many years, but knowledge on the structure mRNAs adopt in vivo is currently missing. Here we solve, for the first time, the in vivo secondary structure of IAV mRNAs in living infected cells. We demonstrate that, compared to the in vitro refolded structure, in vivo IAV mRNAs are less structured but exhibit specific locally stable elements. Moreover, we show that the targeted disruption of these high-confidence structured domains results in an extraordinary attenuation of IAV replicative capacity. Collectively, our data provide the first comprehensive map of the in vivo structural landscape of IAV mRNAs, hence providing the means for the development of new RNA-targeted antivirals.


Author(s):  
Christopher S. Szot ◽  
Cara F. Buchanan ◽  
Joseph W. Freeman ◽  
Marissa Nichole Rylander

Despite the 200 billion dollars invested in cancer therapy research and development since 1971, only 5% of new drugs entering clinical trials successfully obtain FDA approval [1, 2]. There is a growing concern in the cancer research community that this slow movement in progress stems from the need for improved preclinical models for testing new therapeutic agents [1]. A burgeoning interface between cancer research and tissue engineering is transforming how tumor development is being studied in vitro. As a result, complex 3D cancer cell culture models are beginning to be developed with phenotypes representative of in vivo cancer progression [3].


2006 ◽  
Vol 203 (9) ◽  
pp. 2057-2062 ◽  
Author(s):  
Matthias Mueller ◽  
Igor Cima ◽  
Mario Noti ◽  
Andrea Fuhrer ◽  
Sabine Jakob ◽  
...  

The nuclear receptor liver receptor homologue-1 (LRH-1, NR5A2) is a crucial transcriptional regulator of many metabolic pathways. In addition, LRH-1 is expressed in intestinal crypt cells where it regulates the epithelial cell renewal and contributes to tumorigenesis through the induction of cell cycle proteins. We have recently identified the intestinal epithelium as an important extra-adrenal source of immunoregulatory glucocorticoids. We show here that LRH-1 promotes the expression of the steroidogenic enzymes and the synthesis of corticosterone in murine intestinal epithelial cells in vitro. Interestingly, LRH-1 is also essential for intestinal glucocorticoid synthesis in vivo, as LRH-1 haplo-insufficiency strongly reduces the intestinal expression of steroidogenic enzymes and glucocorticoid synthesis upon immunological stress. These results demonstrate for the first time a novel role for LRH-1 in the regulation of intestinal glucocorticoid synthesis and propose LRH-1 as an important regulator of intestinal tissue integrity and immune homeostasis.


2000 ◽  
Vol 355 (1397) ◽  
pp. 623-631 ◽  
Author(s):  
B. Brett Finlay ◽  
John H. Brumell

Salmonellosis (diseases caused by Salmonella species) have several clinical manifestations, ranging from gastroenteritis (food poisoning) to typhoid (enteric) fever and bacteraemia. Salmonella species (especially Salmonella typhimurium ) also represent organisms that can be readily used to investigate the complex interplay that occurs between a pathogen and its host, both in vitro and in vivo. The ease with which S. typhimurium can be cultivated and genetically manipulated, in combination with the availability of tissue culture models and animal models, has made S. typhimurium a desirable organism for such studies. In this review, we focus on Salmonella interactions with its host cells, both in tissue culture ( in vitro ) and in relevant animal models (in vivo), and compare results obtained using these different models. The recent advent of sophisticated imaging and molecular genetic tools has facilitated studying the events that occur in disease, thereby confirming tissue culture results, yet identifying new questions that need to be addressed in relevant disease settings.


Pharmaceutics ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 47
Author(s):  
Rosy Ghanem ◽  
Véronique Laurent ◽  
Philippe Roquefort ◽  
Tanguy Haute ◽  
Sophie Ramel ◽  
...  

The respiratory epithelium can be affected by many diseases that could be treated using aerosol gene therapy. Among these, cystic fibrosis (CF) is a lethal inherited disease characterized by airways complications, which determine the life expectancy and the effectiveness of aerosolized treatments. Beside evaluations performed under in vivo settings, cell culture models mimicking in vivo pathophysiological conditions can provide complementary insights into the potential of gene transfer strategies. Such models must consider multiple parameters, following the rationale that proper gene transfer evaluations depend on whether they are performed under experimental conditions close to pathophysiological settings. In addition, the mucus layer, which covers the epithelial cells, constitutes a physical barrier for gene delivery, especially in diseases such as CF. Artificial mucus models featuring physical and biological properties similar to CF mucus allow determining the ability of gene transfer systems to effectively reach the underlying epithelium. In this review, we describe mucus and cellular models relevant for CF aerosol gene therapy, with a particular emphasis on mucus rheology. We strongly believe that combining multiple pathophysiological features in single complex cell culture models could help bridge the gaps between in vitro and in vivo settings, as well as viral and non-viral gene delivery strategies.


Foods ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2979
Author(s):  
Lin Gao ◽  
Jiawei Yuan ◽  
Yuhuan Cheng ◽  
Mengling Chen ◽  
Genhua Zhang ◽  
...  

Numerous natural compounds are considered as potential therapeutic agents against alcohol-induced liver disease (ALD). Research shows that selenium (Se) has a variety of bioactivities, including liver protecting ability. The present study based on in vitro cell culture models and in vivo mouse models was aimed at examining the contribution of selenomethionine (SeMet)-dominated Se-enriched peanut protein (SePP) to liver protection. SeMet and especially SePP reversed cell viability and cell death, inhibited ethanol induced CYP2E1 activation, decreased reactive oxygen species level, and restored GSH level. Hence, SeMet-dominated SePP alleviates alcohol-induced AML-12 cytotoxicity by suppressing oxidative stress. The p38-dependent mechanism was found to be responsible for SePP-induced Nrf-2 activation. Furthermore, supplementation with SePP and SeMet regulated lipid metabolism and reduced oxidative stress, minimizing liver damage in mice. Selenomethionine-dominated SePP possesses potential therapeutic properties and can be used to treat ALD through the suppression of oxidative stress.


2001 ◽  
Vol 119 (1) ◽  
pp. 3-14 ◽  
Author(s):  
Ray A. Caldwell ◽  
Barbara R. Grubb ◽  
Robert Tarran ◽  
Richard C. Boucher ◽  
Michael R. Knowles ◽  
...  

The pathogenesis of cystic fibrosis (CF) airways disease remains controversial. Hypotheses that link mutations in CFTR and defects in ion transport to CF lung disease predict that alterations in airway surface liquid (ASL) isotonic volume, or ion composition, are critically important. ASL [Cl−] is pivotal in discriminating between these hypotheses, but there is no consensus on this value given the difficulty in measuring [Cl−] in the “thin” ASL (∼30 μm) in vivo. Consequently, a miniaturized solid-state electrode with a shallow depth of immersion was constructed to measure ASL [Cl−] in vivo. In initial experiments, the electrode measured [Cl−] in physiologic salt solutions, small volume (7.6 μl) test solutions, and in in vitro cell culture models, with ≥93% accuracy. Based on discrepancies in reported values and/or absence of data, ASL Cl− measurements were made in the following airway regions and species. First, ASL [Cl−] was measured in normal human nasal cavity and averaged 117.3 ± 11.2 mM (n = 6). Second, ASL [Cl−] measured in large airway (tracheobronchial) regions were as follows: rabbit trachea and bronchus = 114.3 ± 1.8 mM; (n = 6) and 126.9 ± 1.7 mM; (n = 3), respectively; mouse trachea = 112.8 ± 4.2 mM (n = 13); and monkey bronchus = 112.3 ± 10.9 mM (n = 3). Third, Cl− measurements were made in small (1–2 mm) diameter airways of the rabbit (108.3 ± 7.1 mM, n = 5) and monkey (128.5 ± 6.8 mM, n = 3). The measured [Cl−], in excess of 100 mM throughout all airway regions tested in multiple species, is consistent with the isotonic volume hypothesis to describe ASL physiology.


2012 ◽  
Vol 4 (1) ◽  
pp. 1-19 ◽  
Author(s):  
Barbara Rothen-Rutishauser ◽  
Martin J.D. Clift ◽  
Corinne Jud ◽  
Alke Fink ◽  
Peter Wick

AbstratThe human body can be exposed to nanomaterials through a variety of different routes. As nanomaterials get in contact with the skin, the gastrointestinal tract, and the respiratory tract, these biological compartments are acting as barriers to the passage of nano-sized materials into the organism. These structural and functional barriers are provided by the epithelia serving as an interface between biological compartments. In order to initiate the reduction, refinement and replacement of time consuming, expensive and stressful (to the animals) in vivo experimental approaches, many in vitro epithelial cell culture models have been developed during the last decades. This review therefore, focuses on the functional as well as structural aspects of epithelial cells as well as the most commonly used in vitro epithelial models of the primary biological barriers with which nanomaterials might come in contact with either occupationally, or during their manufacturing and application. The advantages and disadvantages of the different in vitro models are discussed in order to provide a clear overview as to whether or not epithelial cell cultures are an advantageous model to be used for basic mechanism and nanotoxicology research.


2018 ◽  
Vol 9 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Mar Pérez ◽  
Miguel Medina ◽  
Félix Hernández ◽  
Jesús Avila

AbstractThe microtubule-associated protein Tau plays a crucial role in stabilizing neuronal microtubules. In Tauopathies, Tau loses its ability to bind microtubules, detach from them and forms intracellular aggregates. Increasing evidence in recent years supports the notion that Tau pathology spreading throughout the brain in AD and other Tauopathies is the consequence of the propagation of specific Tau species along neuroanatomically connected brain regions in a so-called “prion-like” manner. A number of steps are assumed to be involved in this process, including secretion, cellular uptake, transcellular transfer and/or seeding, although the precise mechanisms underlying propagation of Tau pathology are not fully understood yet. This review summarizes recent evidence on the nature of the specific Tau species that are propagated and the different mechanisms of Tau pathology spreading.


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