Background & Aims: We recently identified lysophosphatidic acid (LPA) as a potent antiapoptotic agent for the intestinal epithelium. The objective of the present study was to evaluate the effect of octadecenyl thiophosphate (OTP), a novel rationally designed, metabolically stabilized LPA mimic, on radiation-induced apoptosis of intestinal epithelial cells in vitro and in vivo.

Methods: The receptors and signaling pathways activated by OTP were examined in IEC-6 and RH7777 cell lines and wild-type and LPA(1) and LPA(2) knockout mice exposed to different apoptotic stimuli.

Results: OTP was more efficacious than LPA in reducing gamma irradiation-, camptothecin-, or tumor necrosis factor alpha/cycloheximide-induced apoptosis and caspase-3-8, and caspase-9 activity in the IEC-6 cell line. In RH7777 cells lacking LPA receptors, OTP selectively protected LPA(2) but not LPA(1) and LPA(3) transfectants. In C57BL/6 and LPA(1) knockout mice exposed to 15 Gy gamma irradiation, orally applied OTP reduced the number of apoptotic bodies and activated caspase-3-positive cells but was ineffective in LPA(2) knockout mice. OTP, with higher efficacy than LPA, enhanced intestinal crypt survival in C57BL/6 mice but was without any effect in LPA(2) knockout mice. Intraperitoneally administered OTP reduced death caused by lethal dose (LD)(100/30) radiation by 50%.

Conclusions: Our data indicate that OTP is a highly effective antiapoptotic agent that engages similar prosurvival pathways to LPA through the LPA(2) receptor subtype.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3446791PMC
http://dx.doi.org/10.1053/j.gastro.2007.03.038DOI Listing

Publication Analysis

Top Keywords

knockout mice
16
lpa2 knockout
12
lysophosphatidic acid
8
antiapoptotic agent
8
otp
8
mice exposed
8
otp reduced
8
lpa
6
lpa2
5
mice
5

Similar Publications

In mice, naturally occurring and induced mutations in the suppressor of cytokine signaling-2 () gene are associated with a high growth phenotype characterized by rapid post-weaning weight gain and 30-50% heavier mature body weight. In this work, we demonstrate an electroporation-based method of producing knock-out (KO) sheep. Electroporation of dual-guide CRISPR-Cas9 ribonucleoprotein complexes targeting was performed 6 h post-fertilization in sheep zygotes.

View Article and Find Full Text PDF

Inhibition of IFITM3 in cerebrovascular endothelium alleviates Alzheimer's-related phenotypes.

Alzheimers Dement

January 2025

Center for Geriatric Medicine, Key Laboratory of Alzheimer's Disease of Zhejiang Province, The First Affiliated Hospital and Institute of Aging, Wenzhou Medical University, Wenzhou, Zhejiang, China.

Introduction: Interferon-induced transmembrane protein 3 (IFITM3) modulates γ-secretase in Alzheimer's Disease (AD). Although IFITM3 knockout reduces amyloid β protein (Aβ) production, its cell-specific effect on AD remains unclear.

Methods: Single nucleus RNA sequencing (snRNA-seq) was used to assess IFITM3 expression.

View Article and Find Full Text PDF

Tumor development often requires cellular adaptation to a unique, high metabolic state; however, the molecular mechanisms that drive such metabolic changes in TFE3-rearranged renal cell carcinoma (TFE3-RCC) remain poorly understood. TFE3-RCC, a rare subtype of RCC, is defined by the formation of chimeric proteins involving the transcription factor TFE3. In this study, we analyzed cell lines and genetically engineered mice, demonstrating that the expression of the chimeric protein PRCC-TFE3 induced a hypoxia-related signature by transcriptionally upregulating HIF1α and HIF2α.

View Article and Find Full Text PDF

DNMT3A loss drives a HIF-1-dependent synthetic lethality to HDAC6 inhibition in non-small cell lung cancer.

Acta Pharm Sin B

December 2024

Department of Pharmacology, School of Life Science and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang 110016, China.

encodes a DNA methyltransferase involved in development, cell differentiation, and gene transcription, which is mutated and aberrant-expressed in cancers. Here, we revealed that loss of promotes malignant phenotypes in lung cancer. Based on the epigenetic inhibitor library synthetic lethal screening, we found that small-molecule HDAC6 inhibitors selectively killed -defective NSCLC cells.

View Article and Find Full Text PDF

Background: Obstructive sleep apnea (OSA) is frequently associated with increased incidence and mortality of pulmonary hypertension (PH). The immune response contributes to pulmonary artery remodeling and OSA-related diseases. The immunologic factors linked to OSA-induced PH are not well understood.

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!