All issues > Volume 51(2); 2008

Original Article

Korean J Pediatr. 2008;51(2):170-180. Published online February 15, 2008.

Neuroprotective effects of geneticin (G418) via apoptosis in perinatal hypoxic-ischemic brain injury

Mi M Ju¹, Hyun Ju HJ Lee¹, Sun Ju SJ Lee², Eo Su ES Seo³, Hye Jin HJ Park¹, Kye Yang KY Lee¹, Gyeong Hoon GH Lee¹, Eun Jin EJ Choi¹, Jin Kyung JK Kim¹, Jong Won JW Lee⁴, Hai Lee HL Chung¹, Woo Taek WT Kim¹

¹Department of Pediatrics, Catholic University of Daegu, Daegu, Korea
²Department of Pediatrics, School of Medicine, DongGuk University, Kyeong-Ju, Korea
³Department of Ophthalmology, School of Medicine, DongGuk University, Kyeong-Ju, Korea
⁴Department of Biochemistry, School of Medicine, Catholic University of Daegu, Daegu, Korea

Correspondence Woo Taek WT Kim ,Email: wootykim@cu.ac.kr

Abstract

Purpose
: Some antibiotics were known to exert neuroprotective effects in the animal model of hypoxic-ischemic (H-I) brain injury, but the mechanism is still unclear. A recent study reported that geneticin (G418), an aminoglycoside antibiotic, increased survival of human breast cancer cells by suppressing apoptosis. We investigated the neuroprotective effects of systemically administrated geneticin via anti-apoptosis following the H-I brain injury
Methods
: Seven-day-old Sprague-Dawley rat pups were subjected to unilateral (left) common carotid artery occlusion followed by 2.5 hours of hypoxic exposure and the cortical cell culture of rat brain was done under a hypoxic incubator. Apoptosis was measured in the injured hemispheres 7 days after H-I insult and in the injured cells from hypoxic chamber using morphologic analysis by Terminal dUTP Nick-end Labeling(TUNEL) assay and immunohistochemistry for caspase-3, and cytologic analysis by western blot and real time PCR for bax, bcl-2, and caspase-3.
Results
: The gross appearance and hematoxylin and eosin stain revealed increased brain volume in the geneticin-treated animal model of perinatal H-I brain injury. The TUNEL assay revealed decreased apoptotic cells after administration of geneticin in the cell culture model of anoxia. Immunohistochemistry showed decreased caspase-3 expression in geneticin-treated cortical cell culture. Western blot and real-time PCR showed decreased caspase-3 expression and decreased ratio of Bax/ Bcl-2 expression in geneticin-treated animal model.
Conclusion
: Geneticin appears to exert a neuroprotective effect against perinatal H-I brain injury at least via anti-apoptosis. However, more experiments are needed in order to demonstrate the usefulness of geneticin as a preventive and rescue treatment for H-I brain injuries of neonatal brain.

Keywords :Hypoxic-ischemic brain injury, Anti-apoptosis, Perinatal, Geneticin, G418