Presentation Authors: Su Jin Kim*, Wonju, Korea, Republic of, Young Sam Cho, Seoul, Korea, Republic of, Khae Hawn Kim, Incheon, Korea, Republic of
Introduction: Spinal cord injury (SCI) is a serious problem causing severe or permanent disability. Even though various treatment methods with various cell types are respectively applied to the SCI patients, there is no efficient method yet. One of the challenging therapies for this problem is phosphatase and tensin homolog deleted on chromosome 10 (PTEN) inhibitors. The PTEN inhibitors have been used to facilitate neuroprotection and axonal outgrowth. Therefore, we investigated the effects of PTEN inhibitors on voiding and motor function after SCI.
Methods: Female rats were randomly divided into five groups (n = 10 in each group): the sham-operation group, the SCI-induced group, the SCI-induced and PTEN inhibitor type I treated group, the SCI-induced and PTEN inhibitor type II treated group, and the SCI-induced and PTEN inhibitor type III treated group. SCI was induced by contusion injury at T9-T10 level. After injury, PTEN inhibitor was directly administered to the site of injury for 14 days. Cystometry, Basso, Beattie and Bresnahan (BBB) scale test, ladder walking test, hematoxylin and eosin staining, and western blot for Brain-derived neurotrophic factor(BDNF), vascular endothelial growth factor(VEGF), nerve growth factor(NGF) were performed.
Results: After PTEN inhibitor treatment, enhanced walking ability and coordinative function was observed. Cystometry showed improvement of increased contraction pressure and shortened contraction interval. Basal contraction pressure and time were increased in the PTEN inhibitor-treated groups compared with the SCI group, especially and basal contraction pressure was higher in the PTEN inhibitor type II and type III groups. This means that the SCI has damaged the urinary signaling system. However, PTEN inhibitor treatment can be considered to increase the signal of urination that caused the dysfunction due to the SCI. PTEN inhibitors significantly inhibited the overexpression of VEGF, BDNF, and NGF.
Conclusions: PTEN inhibitors inhibited overexpressed growth factors and promoted repair of damaged tissue. They also showed improved voiding and motor function. Therefore, we suggest that PTEN inhibitors as a new therapeutic agent that can be applied after SCI.