Rh-CSF1 Attenuates Oxidative Stress and Neuronal Apoptosis via the CSF1R/PLCG2/PKA/UCP2 Signaling Pathway in a Rat Model of Neonatal HIE.

Abstract

Oxidative stress (OS) and neuronal apoptosis are major pathological processes after hypoxic-ischemic encephalopathy (HIE). Colony stimulating factor 1 (CSF1), binding to CSF1 receptor (CSF1R), has been shown to reduce neuronal loss after hypoxic-ischemia- (HI-) induced brain injury. In the present study, we hypothesized that CSF1 could alleviate OS-induced neuronal degeneration and apoptosis through the CSF1R/PLCG2/PKA/UCP2 signaling pathway in a rat model of HI. A total of 127 ten-day old Sprague Dawley rat pups were used. HI was induced by right common carotid artery ligation with subsequent exposure to hypoxia for 2.5 h. Exogenous recombinant human CSF1 (rh-CSF1) was administered intranasally at 1 h and 24 h after HI. The CSF1R inhibitor, BLZ945, or phospholipase C-gamma 2 (PLCG2) inhibitor, U73122, was injected intraperitoneally at 1 h before HI induction. Brain infarct volume measurement, cliff avoidance test, righting reflex test, double immunofluorescence staining, western blot assessment, 8-OHdG and MitoSOX staining, Fluoro-Jade C staining, and TUNEL staining were used. Our results indicated that the expressions of endogenous CSF1, CSF1R, p-CSF1R, p-PLCG2, p-PKA, and uncoupling protein2 (UCP2) were increased after HI. CSF1 and CSF1R were expressed in neurons and astrocytes. Rh-CSF1 treatment significantly attenuated neurological deficits, infarct volume, OS, neuronal apoptosis, and degeneration at 48 h after HI. Moreover, activation of CSF1R by rh-CSF1 significantly increased the brain tissue expressions of p-PLCG2, p-PKA, UCP2, and Bcl2/Bax ratio, but reduced the expression of cleaved caspase-3. The neuroprotective effects of rh-CSF1 were abolished by BLZ945 or U73122. These results suggested that rh-CSF1 treatment attenuated OS-induced neuronal degeneration and apoptosis after HI, at least in part, through the CSF1R/PLCG2/PKA/UCP2 signaling pathway. Rh-CSF1 may serve as therapeutic strategy against brain damage in patients with HIE.

• Authors: Xiao Hu, Shirong Li, Desislava Met Doycheva, Lei Huang, Cameron Lenahan, Rui Liu, Juan Huang, Ling Gao, Jiping Tang, Gang Zuo, John H Zhang
• Journal: Oxidative medicine and cellular longevity (Oxid Med Cell Longev) Vol. 2020 Pg. 6801587 ( 2020) ISSN: 1942-0994 [Electronic] United States
• PMID: 33101590 (Publication Type: Journal Article)
• Copyright: Copyright © 2020 Xiao Hu et al.

Chemical References

• 4-(2-(2-hydroxycyclohexylamino)benzothiazol-6-yloxy)pyridine-2-carboxylic acid methylamide
• Benzothiazoles
• CSF1 protein, human
• Neuroprotective Agents
• Picolinic Acids
• Proto-Oncogene Proteins c-bcl-2
• Receptors, Granulocyte-Macrophage Colony-Stimulating Factor
• Recombinant Proteins
• Ucp2 protein, rat
• Uncoupling Protein 2
• Macrophage Colony-Stimulating Factor
• Cyclic AMP-Dependent Protein Kinases
• Phospholipase C gamma

Topics

• Animals
• Apoptosis (drug effects)
• Benzothiazoles (pharmacology)
• Cyclic AMP-Dependent Protein Kinases (metabolism)
• Disease Models, Animal
• Humans
• Hypoxia-Ischemia, Brain (pathology)
• Macrophage Colony-Stimulating Factor (genetics, metabolism, pharmacology)
• Neurons (cytology, metabolism)
• Neuroprotective Agents (pharmacology)
• Oxidative Stress (drug effects)
• Phospholipase C gamma (antagonists & inhibitors, metabolism)
• Picolinic Acids (pharmacology)
• Proto-Oncogene Proteins c-bcl-2 (metabolism)
• Rats
• Rats, Sprague-Dawley
• Receptors, Granulocyte-Macrophage Colony-Stimulating Factor (antagonists & inhibitors, metabolism)
• Recombinant Proteins (biosynthesis, pharmacology)
• Signal Transduction (drug effects)
• Uncoupling Protein 2 (metabolism)
• Up-Regulation (drug effects)