Protein phosphatase 2B inhibitor potentiates endothelial PKC activity and barrier dysfunction.

Am J Physiol Lung Cell Mol Physiol

Department of Pharmacology, Rush-Presbyterian-St. Luke's Medical Center, Chicago, Illinois 60612, USA.

Published: September 2001

Serine/threonine (Ser/Thr) protein phosphatases (PPs) are implicated in the recovery from endothelial barrier dysfunction caused by inflammatory mediators. We hypothesized that Ser/Thr PPs may regulate protein kinase C (PKC), a critical signaling molecule in barrier dysfunction, in the promotion of barrier recovery. Western analysis indicated that bovine pulmonary microvascular endothelial cells (BPMECs) expressed the three major Ser/Thr PPs, PP1, PP2A, and PP2B. Pretreatment with 100 ng/ml of FK506 (a PP2B inhibitor) but not with the PP1 and PP2A inhibitors calyculin A or okadaic acid potentiated the thrombin-induced increase in PKC phosphotransferase activity. FK506 also potentiated thrombin-induced PKC-alpha but not PKC-beta phosphorylation. FK506 but not calyculin A or okadaic acid inhibited recovery from the thrombin-induced decrease in transendothelial resistance. Neither FK506 nor okadaic acid altered the thrombin-induced resistance decrease, whereas calyculin A potentiated the decrease. Downregulation of PKC with phorbol 12-myristate 13-acetate rescued the FK506-mediated inhibition of recovery, which was consistent with the finding that the thrombin-induced phosphorylation of PKC-alpha was reduced during the recovery phase. These results indicated that PP2B may play a physiologically important role in returning endothelial barrier dysfunction to normal through the regulation of PKC.

Download full-text PDF

Source
http://dx.doi.org/10.1152/ajplung.2001.281.3.L546DOI Listing

Publication Analysis

Top Keywords

barrier dysfunction
16
okadaic acid
12
endothelial barrier
8
ser/thr pps
8
pp1 pp2a
8
calyculin okadaic
8
potentiated thrombin-induced
8
pkc
5
barrier
5
recovery
5

Similar Publications

Discovery of pyrazoline analogs as multi-targeting cholinesterase, β-secretase and Aβ aggregation inhibitors through lead optimization strategy.

Int J Biol Macromol

January 2025

Pharmaceutical Chemistry Research Laboratory I, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India. Electronic address:

The multi-target directed ligands (MTDLs) strategy has been evolved as the propitious approach for the development of therapeutics for Alzheimer's disease (AD). In an earlier report, we described the novel series of chalcone derivatives bearing N-aryl piperazine scaffold as MTDLs for the treatment of AD. Herein, we report the lead optimization of the series culminating in potent, multi-targeting compounds (32-57), evaluated through in-vitro and in-vivo biological studies.

View Article and Find Full Text PDF

Acute hyperglycemia impedes spinal cord injury recovery via triggering excessive ferroptosis of endothelial cells.

Int J Biol Macromol

January 2025

The Institute of Life Sciences, Engineering Laboratory of Zhejiang Province for Pharmaceutical Development of Growth Factors, Wenzhou University, Wenzhou 325035, China; The Orthopaedic Center, The First People's Hospital of Wenling, Affiliated Wenling Hospital and School of Pharmaceutical Science, Wenzhou Medical University, Taizhou, Zhejiang 317500, China. Electronic address:

Spinal cord injury (SCI) is a serious central nervous system injury that often causes sensory and motor dysfunction in patients. Diabetes seriously destroys the blood spinal cord barrier (BSCB) and aggravates SCI. Ferroptosis is a new type of programmed cell death.

View Article and Find Full Text PDF

Interferon-γ signaling in eosinophilic esophagitis affects epithelial barrier function and programmed cell death.

Cell Mol Gastroenterol Hepatol

January 2025

Division of Allergy and Immunology, Children's Hospital of Philadelphia, Philadelphia, PA, USA; Department of Pediatrics, Perelman School of Medicine at University of Pennsylvania. Electronic address:

Background & Aims: Eosinophilic esophagitis (EoE) is a chronic esophageal inflammatory disorder characterized by eosinophil-rich mucosal inflammation and tissue remodeling. Prior research has revealed the upregulation of interferon (IFN) response signature genes (ISGs) in biopsy tissue from EoE patients, but the specific cell types that contribute to this IFN response and the effect of interferons on the esophageal epithelium remain incompletely understood. Here, we use scRNA-seq to examine the expression of IFN and ISGs during EoE and explore how IFN-α and IFN-γ treatments affect epithelial function.

View Article and Find Full Text PDF

Prognostic values of proteinuria in patients with acute heart failure.

J Cardiol

January 2025

Department of Cardiovascular Biology and Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan; Japan Agency for Medical Research and Development-Core Research for Evolutionary Medical Science and Technology (AMED-CREST), Japan Agency for Medical Research and Development, Tokyo, Japan.

Background: Renal dysfunction is significantly associated with poor prognosis in patients with heart failure. However, the prognostic significance of proteinuria as a potential marker of an impaired glomerular filtration barrier in acute heart failure (AHF) remains unclear. We aimed to investigate the prognostic value of urinary protein/creatinine ratio (PCR) in patients with AHF.

View Article and Find Full Text PDF

Chronic unpredictable stress exposure disrupts testicular function by modulating germ cell-junctional dynamics and Nrf2/HO-1/IKKβ/NF-κB pathway.

Reprod Toxicol

January 2025

Male Reproductive Physiology Lab., Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi-221005 (UP), India. Electronic address:

The unpredictable nature of stress complicates understanding its relationship with male infertility. In this study, we investigated testicular germ cell and junctional dynamics in male mice following exposure to chronic unpredictable stress (CUS). Adult Parkes male mice were exposed to CUS for 35 days (one complete spermatogenic cycle), with a random stressor (restraint stress, water deprivation, food deprivation, light flashing, wet bedding, cage shaking, or cage tilting) applied once per day in an intermittent and unpredictable manner to avoid repeating the same stimulus on consecutive days.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!