scholarly journals The nuclear receptor LRH-1 critically regulates extra-adrenal glucocorticoid synthesis in the intestine

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.

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.


2011 ◽  
Vol 300 (4) ◽  
pp. G561-G567 ◽  
Author(s):  
Svetlana M. Nabokina ◽  
Veedamali S. Subramanian ◽  
Hamid M. Said

Intestinal absorption of biotin is mediated via the sodium-dependent multivitamin transporter (SMVT). Studies from our laboratory and others have characterized different aspects of the human SMVT (hSMVT), but nothing is currently known about protein(s) that may interact with hSMVT and affect its physiology/biology. In this study, a PDZ-containing protein PDZD11 was identified as an interacting partner with hSMVT using yeast two-hybrid screen of a human intestinal cDNA library. The interaction between hSMVT and PDZD11 was confirmed by in vitro GST-pull-down assay and in vivo in a mammalian cell environment by a two-hybrid luciferase and coimmunoprecipitation assays. Furthermore, confocal imaging of live human intestinal epithelial HuTu-80 cells expressing hSMVT-GFP and DsRed-PDZD11 demonstrated colocalization of these two proteins. We also examined the functional consequence of the interaction between hSMVT and PDZD11 in HuTu-80 cells and observed significant induction in [3H]biotin uptake upon coexpression of hSMVT and PDZD11. In contrast, knocking down of PDZD11 with gene-specific small interfering RNA led to a significant decrease in biotin uptake; biotinylation assay showed this to be associated with a marked decrease in level of expression of hSMVT at the cell membrane. By truncation approach, we also demonstrated that the PDZ binding domain that is located in the COOH-terminal tail of hSMVT polypeptide is involved in the interaction with PDZD11. These results demonstrate for the first time that PDZD11 is an interacting partner with hSMVT in intestinal epithelial cells and that this interaction affects hSMVT function and cell biology.


Biomedicines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 819
Author(s):  
Nicolai Rügen ◽  
Timothy P. Jenkins ◽  
Natalie Wielsch ◽  
Heiko Vogel ◽  
Benjamin-Florian Hempel ◽  
...  

Assassin bug venoms are potent and exert diverse biological functions, making them potential biomedical goldmines. Besides feeding functions on arthropods, assassin bugs also use their venom for defense purposes causing localized and systemic reactions in vertebrates. However, assassin bug venoms remain poorly characterized. We collected the venom from the assassin bug Rhynocoris iracundus and investigated its composition and bioactivity in vitro and in vivo. It caused lysis of murine neuroblastoma, hepatoma cells, and healthy murine myoblasts. We demonstrated, for the first time, that assassin bug venom induces neurolysis and suggest that it counteracts paralysis locally via the destruction of neural networks, contributing to tissue digestion. Furthermore, the venom caused paralysis and melanization of Galleria mellonella larvae and pupae, whilst also possessing specific antibacterial activity against Escherichia coli, but not Listeria grayi and Pseudomonas aeruginosa. A combinatorial proteo-transcriptomic approach was performed to identify potential toxins responsible for the observed effects. We identified neurotoxic Ptu1, an inhibitory cystin knot (ICK) toxin homologous to ω-conotoxins from cone snails, cytolytic redulysins homologous to trialysins from hematophagous kissing bugs, and pore-forming hemolysins. Additionally, chitinases and kininogens were found and may be responsible for insecticidal and cytolytic activities. We demonstrate the multifunctionality and complexity of assassin bug venom, which renders its molecular components interesting for potential biomedical applications.


2021 ◽  
Author(s):  
Lijuan Liu ◽  
Shengting Zhang ◽  
Xiaodan Zheng ◽  
Hongmei Li ◽  
Qi Chen ◽  
...  

Fusobacterium nucleatum has been employed for the first time to synthesize fluorescent carbon dots which could be applied for the determination of Fe3+ ions in living cells and bioimaging in vitro and in vivo with excellent biocompatibility.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Tong Chen ◽  
Qiang Chu ◽  
Mengyang Li ◽  
Gaorong Han ◽  
Xiang Li

AbstractElectrodynamic therapy (EDT) has recently emerged as a potential external field responsive approach for tumor treatment. While it presents a number of clear superiorities, EDT inherits the intrinsic challenges of current reactive oxygen species (ROS) based therapeutic treatments owing to the complex tumor microenvironment, including glutathione (GSH) overexpression, acidity and others. Herein for the first time, iron oxide nanoparticles are decorated using platinum nanocrystals (Fe3O4@Pt NPs) to integrate the current EDT with chemodynamic phenomenon and GSH depletion. Fe3O4@Pt NPs can effectively induce ROS generation based on the catalytic reaction on the surface of Pt nanoparticles triggered by electric field (E), and meanwhile it may catalyze intracellular H2O2 into ROS via Fenton reaction. In addition, Fe3+ ions released from Fe3O4@Pt NPs under the acidic condition in tumor cells consume GSH in a rapid fashion, inhibiting ROS clearance to enhance its antitumor efficacy. As a result, considerable in vitro and in vivo tumor inhibition phenomena are observed. This study has demonstrated an alternative concept of combinational therapeutic modality with superior efficacy.


2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Miao-Miao Zhao ◽  
Wei-Li Yang ◽  
Fang-Yuan Yang ◽  
Li Zhang ◽  
Wei-Jin Huang ◽  
...  

AbstractTo discover new drugs to combat COVID-19, an understanding of the molecular basis of SARS-CoV-2 infection is urgently needed. Here, for the first time, we report the crucial role of cathepsin L (CTSL) in patients with COVID-19. The circulating level of CTSL was elevated after SARS-CoV-2 infection and was positively correlated with disease course and severity. Correspondingly, SARS-CoV-2 pseudovirus infection increased CTSL expression in human cells in vitro and human ACE2 transgenic mice in vivo, while CTSL overexpression, in turn, enhanced pseudovirus infection in human cells. CTSL functionally cleaved the SARS-CoV-2 spike protein and enhanced virus entry, as evidenced by CTSL overexpression and knockdown in vitro and application of CTSL inhibitor drugs in vivo. Furthermore, amantadine, a licensed anti-influenza drug, significantly inhibited CTSL activity after SARS-CoV-2 pseudovirus infection and prevented infection both in vitro and in vivo. Therefore, CTSL is a promising target for new anti-COVID-19 drug development.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jakob Weglage ◽  
Friederike Wolters ◽  
Laura Hehr ◽  
Jakob Lichtenberger ◽  
Celina Wulz ◽  
...  

AbstractSchistosomiasis (bilharzia) is a neglected tropical disease caused by parasitic flatworms of the genus Schistosoma, with considerable morbidity in parts of the Middle East, South America, Southeast Asia, in sub-Saharan Africa, and particularly also in Europe. The WHO describes an increasing global health burden with more than 290 million people threatened by the disease and a potential to spread into regions with temperate climates like Corsica, France. The aim of our study was to investigate the influence of S. mansoni infection on colorectal carcinogenic signaling pathways in vivo and in vitro. S. mansoni infection, soluble egg antigens (SEA) and the Interleukin-4-inducing principle from S. mansoni eggs induce Wnt/β-catenin signaling and the protooncogene c-Jun as well as downstream factor Cyclin D1 and markers for DNA-damage, such as Parp1 and γH2a.x in enterocytes. The presence of these characteristic hallmarks of colorectal carcinogenesis was confirmed in colon biopsies from S. mansoni-infected patients demonstrating the clinical relevance of our findings. For the first time it was shown that S. mansoni SEA may be involved in the induction of colorectal carcinoma-associated signaling pathways.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
N. Callizot ◽  
C. Estrella ◽  
S. Burlet ◽  
A. Henriques ◽  
C. Brantis ◽  
...  

AbstractProgranulin (PGRN) is a protein with multiple functions including the regulation of neuroinflammation, neuronal survival, neurite and synapsis growth. Although the mechanisms of action of PGRN are currently unknown, its potential therapeutic application in treating neurodegenerative diseases is huge. Thus, strategies to increase PGRN levels in patients could provide an effective treatment. In the present study, we investigated the effects of AZP2006, a lysotropic molecule now in phase 2a clinical trial in Progressive Supranuclear Palsy patients, for its ability to increase PGRN level and promote neuroprotection. We showed for the first time the in vitro and in vivo neuroprotective effects of AZP2006 in neurons injured with Aβ1–42 and in two different pathological animal models of Alzheimer’s disease (AD) and aging. Thus, the chronic treatment with AZP2006 was shown to reduce the loss of central synapses and neurons but also to dramatically decrease the massive neuroinflammation associated with the animal pathology. A deeper investigation showed that the beneficial effects of AZP2006 were associated with PGRN production. Also, AZP2006 binds to PSAP (the cofactor of PGRN) and inhibits TLR9 receptors normally responsible for proinflammation when activated. Altogether, these results showed the high potential of AZP2006 as a new putative treatment for AD and related diseases.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Wei Zhang ◽  
Guoyu Yin ◽  
Heping Zhao ◽  
Hanzhi Ling ◽  
Zhen Xie ◽  
...  

AbstractIn inflamed joints, enhanced hyaluronic acid (HA) degradation is closely related to the pathogenesis of rheumatoid arthritis (RA). KIAA1199 has been identified as a hyaladherin that mediates the intracellular degradation of HA, but its extracellular function remains unclear. In this study, we found that the serum and synovial levels of secreted KIAA1199 (sKIAA1199) and low-molecular-weight HA (LMW-HA, MW < 100 kDa) in RA patients were significantly increased, and the positive correlation between them was shown for the first time. Of note, treatment with anti-KIAA1199 mAb effectively alleviated the severity of arthritis and reduced serum LMW-HA levels and cytokine secretion in collagen-induced arthritis (CIA) mice. In vitro, sKIAA1199 was shown to mediate exogenous HA degradation by attaching to the cell membrane of RA fibroblast-like synoviosytes (RA FLS). Furthermore, the HA-degrading activity of sKIAA1199 depended largely on its adhesion to the membrane, which was achieved by its G8 domain binding to ANXA1. In vivo, kiaa1199-KO mice exhibited greater resistance to collagen-induced arthritis. Interestingly, this resistance could be partially reversed by intra-articular injection of vectors encoding full-length KIAA1199 instead of G8-deleted KIAA119 mutant, which further confirmed the indispensable role of G8 domain in KIAA1199 involvement in RA pathological processes. Mechanically, the activation of NF-κB by interleukin-6 (IL-6) through PI3K/Akt signaling is suggested to be the main pathway to induce KIAA1199 expression in RA FLS. In conclusion, our study supported the contribution of sKIAA1199 to RA pathogenesis, providing a new therapeutic target for RA by blocking sKIAA1199-mediated HA degradation.


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