Protective effect of Tat fused HPCA protein on neuronal cell death caused by ischemic injury

Hyun Jung Kwon; Hyo Young Jung; Soo Young Choi; In Koo Hwang; Dae Won Kim; Min Jea Shin

doi:10.1016/j.heliyon.2023.e23488

Protective effect of Tat fused HPCA protein on neuronal cell death caused by ischemic injury

Heliyon. 2023 Dec 16;10(1):e23488. doi: 10.1016/j.heliyon.2023.e23488. eCollection 2024 Jan 15.

Authors

Hyun Jung Kwon¹, Hyo Young Jung², Soo Young Choi¹, In Koo Hwang³, Dae Won Kim⁴, Min Jea Shin¹

Affiliations

¹ Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon 24252, Republic of Korea.
² Department of Veterinary Medicine, Institute of Veterinary Science, Chungnam National University, Daejeon 34134, Republic of Korea.
³ Department of Anatomy and Cell Biology, College of Veterinary Medicine, Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Republic of Korea.
⁴ Department of Biochemistry and Molecular Biology, Research Institute of Oral Sciences, College of Dentistry, Gangneung-Wonju National University, Gangneung 25457, Republic of Korea.

Abstract

Background: Bain ischemia is a disease that occurs for various reasons, induces reactive oxygen species (ROS), and causes fatal damage to the nervous system. Protective effect of HPCA on ischemic injury has not been extensively studied despite its significance in regulating calcium homeostasis and promoting neuronal survival in CA1 region of the brain.

Objective: We investigate the role of HPCA in ischemic injury using a cell-permeable Tat peptide fused HPCA protein (Tat-HPCA).

Methods: Western blot analysis determined the penetration of Tat-HPCA into HT-22 cells and apoptotic signaling pathways. 5-CFDA, AM, DCF-DA, and TUNEL staining confirmed intracellular ROS production and DNA damage. The intracellular Ca²⁺ was measured in primary cultured neurons treated with H₂O₂. Protective effects were examined using immunohistochemistry and cognitive function tests by passive avoidance test and 8-arm radial maze test.

Results: Tat-HPCA effectively penetrated into HT-22 cells and inhibited H₂O₂-induced apoptosis, oxidative stress, and DNA fragmentation. It also effectively inhibited phosphorylation of JNK and regulated the activation of Caspase, Bax, Bcl-2, and PARP, leading to inhibition of apoptosis. Moreover, Ca²⁺ concentration decreased in cells treated with Tat-HPCA in primary cultured neurons. In an animal model of ischemia, Tat-HPCA effectively penetrated the hippocampus, inhibited cell death, and regulated activities of astrocytes and microglia. Additionally, Cognitive function tests show that Tat-HPCA improves neurobehavioral outcomes after cerebral ischemic injury.

Conclusion: These results suggest that Tat-HPCA might have potential as a therapeutic agent for treating oxidative stress-related diseases induced by ischemic injury, including ischemia.

Keywords: Brain ischemia; Oxidative stress; Protein therapy; Protein transduction domain; Tat-HPCA.