scholarly journals A Potent Leukocyte Transmigration Blocker: GT-73 Showed a Protective Effect against LPS-Induced ARDS in Mice

Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4583
Author(s):  
Eliav Blum ◽  
Raanan Margalit ◽  
Laura Levy ◽  
Tamar Getter ◽  
Ron Lahav ◽  
...  
Keyword(s):  
Methyl Ester ◽  
Mouse Model ◽  
Human Leukocyte ◽  
Transendothelial Migration ◽  
Lavage Fluid ◽  
Drug Candidate ◽  
Peripheral Tissues ◽  
Migration Assay ◽  
Tert Butyl ◽  
Leukocyte Transendothelial Migration

We recently developed a molecule (GT-73) that blocked leukocyte transendothelial migration from blood to the peripheral tissues, supposedly by affecting the platelet endothelial cell adhesion molecule (PECAM-1) function. GT-73 was tested in an LPS-induced acute respiratory distress syndrome (ARDS) mouse model. The rationale for this is based on the finding that the mortality of COVID-19 patients is partly caused by ARDS induced by a massive migration of leukocytes to the lungs. In addition, the role of tert-butyl and methyl ester moieties in the biological effect of GT-73 was investigated. A human leukocyte, transendothelial migration assay was applied to validate the blocking effect of GT-73 derivatives. Finally, a mouse model of LPS-induced ARDS was used to evaluate the histological and biochemical effects of GT-73. The obtained results showed that GT-73 has a unique structure that is responsible for its biological activity; two of its chemical moieties (tert-butyl and a methyl ester) are critical for this effect. GT-73 is a prodrug, and its lipophilic tail covalently binds to PECAM-1 via Lys536. GT-73 significantly decreased the number of infiltrating leukocytes in the lungs and reduced the inflammation level. Finally, GT-73 reduced the levels of IL-1β, IL-6, and MCP-1 in bronchoalveolar lavage fluid (BALF). In summary, we concluded that GT-73, a blocker of white blood cell transendothelial migration, has a favorable profile as a drug candidate for the treatment of ARDS in COVID-19 patients.

scholarly journals Endocan regulates acute lung inflammation through control of leukocyte diapedesis

2019 ◽  
Vol 127 (3) ◽  
pp. 668-678 ◽  
Author(s):  
Alexandre Gaudet ◽  
Lucie Portier ◽  
Méline Prin ◽  
Marie-Christine Copin ◽  
Anne Tsicopoulos ◽  
...  
Keyword(s):  
Acute Respiratory Distress Syndrome ◽  
Acute Lung Injury ◽  
Lung Injury ◽  
Lung Inflammation ◽  
Distress Syndrome ◽  
Human Leukocyte ◽  
Transendothelial Migration ◽  
Acute Lung Inflammation ◽  
Leukocyte Transendothelial Migration

Acute respiratory distress syndrome is a severe form of respiratory failure, occurring in up to 20% of patients admitted to the intensive care unit with sepsis. Dysregulated leukocyte diapedesis is a major contributor to acute respiratory distress syndrome. Endocan is a circulating proteoglycan that binds to the leukocyte integrin leukocyte functional antigen-1 and blocks its interaction with its endothelial ligand, ICAM-1. The objective of this study was to evaluate the role of endocan in the control of acute lung inflammation. In vitro, endocan inhibited human leukocyte transendothelial migration as well as ICAM-1-dependent migration but had a very mild effect on ICAM-1-dependent adhesion. Endocan also acted as an inhibitor of transendothelial migration of mouse leukocytes. The effect of systemic administration of recombinant human endocan was assessed in a model of acute lung inflammation in BALB/c mice. Treatment with endocan 1 h after intratracheal LPS challenge reduced the alveolar inflammatory response, diminished histological features of acute lung injury, and improved respiratory function. These results highlight the anti-inflammatory role of human endocan and its protective effect against acute lung injury. NEW & NOTEWORTHY We show here that endocan inhibits ICAM-1-dependent human leukocyte transendothelial migration and ICAM-1-dependent adhesion. We also found that in BALB/c mice with tracheal LPS-induced acute lung injury treatment with recombinant human endocan reduces lung inflammation, notably through reduction of neutrophilic recruitment, and restores normal lung function. These results confirm the hypothesis that human endocan may have a protective effect against acute lung inflammation.

Analysis of bronchoalveolar lavage fluid in a mouse model of bronchial asthma and H1N1 2009 infection

Cytokine ◽  
2013 ◽  
Vol 63 (2) ◽  
pp. 194-200 ◽  
Author(s):  
Seigo Okada ◽  
Shunji Hasegawa ◽  
Hideki Hasegawa ◽  
Akira Ainai ◽  
Ryo Atsuta ◽  
...  
Keyword(s):  
Mouse Model ◽  
Bronchoalveolar Lavage ◽  
Bronchial Asthma ◽  
Bronchoalveolar Lavage Fluid ◽  
Lavage Fluid

scholarly journals NSC828779 Alleviates Renal Tubulointerstitial Lesions Involving Interleukin-36 Signaling in Mice

Cells ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 3060
Author(s):  
Shin-Ruen Yang ◽  
Szu-Chun Hung ◽  
Lichieh Julie Chu ◽  
Kuo-Feng Hua ◽  
Chyou-Wei Wei ◽  
...  
Keyword(s):  
Mouse Model ◽  
Nlrp3 Inflammasome ◽  
Renal Tissue ◽  
Drug Candidate ◽  
Therapeutic Effects ◽  
Tubulointerstitial Lesions ◽  
Cytokine Levels ◽  
Renal Tubular ◽  
Stage Renal Disease ◽  
End Stage

Renal tubulointerstitial lesions (TILs), a common pathologic hallmark of chronic kidney disease that evolves to end-stage renal disease, is characterized by progressive inflammation and pronounced fibrosis of the kidney. However, current therapeutic approaches to treat these lesions remain largely ineffectual. Previously, we demonstrated that elevated IL-36α levels in human renal tissue and urine are implicated in impaired renal function, and IL-36 signaling enhances activation of NLRP3 inflammasome in a mouse model of TILs. Recently, we synthesized NSC828779, a salicylanilide derivative (protected by U.S. patents with US 8975255 B2 and US 9162993 B2), which inhibits activation of NF-κB signaling with high immunomodulatory potency and low IC50, and we hypothesized that it would be a potential drug candidate for renal TILs. The current study validated the therapeutic effects of NSC828779 on TILs using a mouse model of unilateral ureteral obstruction (UUO) and relevant cell models, including renal tubular epithelial cells under mechanically induced constant pressure. Treatment with NSC828779 improved renal lesions, as demonstrated by dramatically reduced severity of renal inflammation and fibrosis and decreased urinary cytokine levels in UUO mice. This small molecule specifically inhibits the IL-36α/NLRP3 inflammasome pathway. Based on these results, the beneficial outcome represents synergistic suppression of both the IL-36α-activated MAPK/NLRP3 inflammasome and STAT3- and Smad2/3-dependent fibrogenic signaling. NSC828779 appears justified as a new drug candidate to treat renal progressive inflammation and fibrosis.

scholarly journals A novel antioxidant ergothioneine PET radioligand for in vivo imaging applications

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
William J. Behof ◽  
Clayton A. Whitmore ◽  
Justin R. Haynes ◽  
Adam J. Rosenberg ◽  
Mohammed N. Tantawy ◽  
...  
Keyword(s):  
Amino Acid ◽  
Mouse Model ◽  
Peripheral Tissues ◽  
Molar Activity ◽  
Model Of Alzheimer’S Disease ◽  
Specific Retention ◽  
5Xfad Mice ◽  
The Brain

AbstractErgothioneine (ERGO) is a rare amino acid mostly found in fungi, including mushrooms, with recognized antioxidant activity to protect tissues from damage by reactive oxygen species (ROS) components. Prior to this publication, the biodistribution of ERGO has been performed solely in vitro using extracted tissues. The aim of this study was to develop a feasible chemistry for the synthesis of an ERGO PET radioligand, [11C]ERGO, to facilitate in vivo study. The radioligand probe was synthesized with identical structure to ERGO by employing an orthogonal protection/deprotection approach. [11C]methylation of the precursor was performed via [11C]CH3OTf to provide [11C]ERGO radioligand. The [11C]ERGO was isolated by RP-HPLC with a molar activity of 690 TBq/mmol. To demonstrate the biodistribution of the radioligand, we administered approximately 37 MBq/0.1 mL in 5XFAD mice, a mouse model of Alzheimer’s disease via the tail vein. The distribution of ERGO in the brain was monitored using 90-min dynamic PET scans. The delivery and specific retention of [11C]ERGO in an LPS-mediated neuroinflammation mouse model was also demonstrated. For the pharmacokinetic study, the concentration of the compound in the serum started to decrease 10 min after injection while starting to distribute in other peripheral tissues. In particular, a significant amount of the compound was found in the eyes and small intestine. The radioligand was also distributed in several regions of the brain of 5XFAD mice, and the signal remained strong 30 min post-injection. This is the first time the biodistribution of this antioxidant and rare amino acid has been demonstrated in a preclinical mouse model in a highly sensitive and non-invasive manner.

scholarly journals Suppression of Airway Allergic Reactions by a Photocatalytic Filter Using Mouse Model

Toxics ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 40
Author(s):  
Taisuke Tomonaga ◽  
Hiroto Izumi ◽  
Chinatsu Nishida ◽  
Kaori Kato ◽  
Kazuhiro Yatera ◽  
...  
Keyword(s):  
Titanium Dioxide ◽  
Mouse Model ◽  
Respiratory Tract ◽  
Bronchoalveolar Lavage ◽  
Experimental Model ◽  
Bronchoalveolar Lavage Fluid ◽  
Lavage Fluid ◽  
Specific Ige ◽  
Allergic Reactions ◽  
Living Organisms

Photocatalytic filters installed in air purifiers have been used to purify spaces by decomposing allergenic substances. However, we have not found any reports that evaluate the effectiveness of photocatalytic filters in suppressing allergic reactions in living organisms. In this study, we intratracheally instilled ovalbumin (OVA) into OVA-sensitized mice after the OVA was photocatalyzed by a titanium dioxide (TiO2) filter, and verified the experimental model for evaluating the allergy-suppressing effect of photocatalysts. Mice were sensitized to OVA (10 µg/mouse) four times, and were intratracheally instilled with OVA (10 µg/mouse) after photocatalysis three times. Non-sensitized animals were instilled with normal saline following the same exposure schedule. The mice were dissected 24 h after final exposure. The OVA after photocatalysis significantly decreased the number of eosinophils in bronchoalveolar lavage fluid, and the concentration of OVA-specific IgE and IgG1 in serum, which were elevated in untreated OVA. Moreover, our experimental model showed the suppression of allergic reactions in mice, along with the decomposition of OVA after photocatalysis using the photocatalytic filter. Taken together, our experimental model for evaluating allergic reactions in the respiratory tract suggested that the allergy-suppressing effect of the photocatalytic filter can be evaluated.

scholarly journals TRPC6 is the endothelial calcium channel that regulates leukocyte transendothelial migration during the inflammatory response

2015 ◽  
Vol 212 (11) ◽  
pp. 1883-1899 ◽  
Author(s):  
Evan W. Weber ◽  
Fei Han ◽  
Mohammad Tauseef ◽  
Lutz Birnbaumer ◽  
Dolly Mehta ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Inflammatory Response ◽  
Calcium Channel ◽  
Transient Receptor Potential ◽  
Leukocyte Adhesion ◽  
Transendothelial Migration ◽  
Dominant Negative ◽  
Ion Concentration ◽  
Free Calcium ◽  
Leukocyte Transendothelial Migration

Leukocyte transendothelial migration (TEM) is a tightly regulated, multistep process that is critical to the inflammatory response. A transient increase in endothelial cytosolic free calcium ion concentration (↑[Ca2+]i) is required for TEM. However, the mechanism by which endothelial ↑[Ca2+]i regulates TEM and the channels mediating this ↑[Ca2+]i are unknown. Buffering ↑[Ca2+]i in endothelial cells does not affect leukocyte adhesion or locomotion but selectively blocks TEM, suggesting a role for ↑[Ca2+]i specifically for this step. Transient receptor potential canonical 6 (TRPC6), a Ca2+ channel expressed in endothelial cells, colocalizes with platelet/endothelial cell adhesion molecule-1 (PECAM) to surround leukocytes during TEM and clusters when endothelial PECAM is engaged. Expression of dominant-negative TRPC6 or shRNA knockdown in endothelial cells arrests neutrophils apically over the junction, similar to when PECAM is blocked. Selectively activating endothelial TRPC6 rescues TEM during an ongoing PECAM blockade, indicating that TRPC6 functions downstream of PECAM. Furthermore, endothelial TRPC6 is required for trafficking of lateral border recycling compartment membrane, which facilitates TEM. Finally, mice lacking TRPC6 in the nonmyeloid compartment (i.e., endothelium) exhibit a profound defect in neutrophil TEM with no effect on leukocyte trafficking. Our findings identify endothelial TRPC6 as the calcium channel mediating the ↑[Ca2+]i required for TEM at a step downstream of PECAM homophilic interactions.

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