In Vivo Spinal Distribution of Cy5.5 Fluorescent Dye after Injection via the Lateral Ventricle and Cisterna Magna in Rat Model

OBJECTIVE: The purpose of this study was to find an optimal delivery route for clinical trials of intrathecal cell therapy for spinal cord injury in preclinical stage.METHODS: We compared in vivo distribution of Cy5.5 fluorescent dye in the spinal cord region at various time points utilizing in vivo optical imaging techniques, which was injected into the lateral ventricle (LV) or cisterna magna (CM) of rats.RESULTS: Although CM locates nearer to the spinal cord than the LV, significantly higher signal of Cy5.5 was detected in the thoracic and lumbar spinal cord region at all time points tested when Cy5.5 was injected into the LV. In the LV injection Cy5.5 signal in the thoracic and lumbar spinal cord was observed within 12 hours after injection, which was maintained until 72 hours after injection. In contrast, Cy5.5 signal was concentrated at the injection site in the CM injection at all time points.CONCLUSION: These data suggested that the LV might be suitable for preclinical injection route of therapeutics targeting the spinal cord to test their treatment efficacy and biosafety for spinal cord diseases in small animal models.

In Vivo Spinal Distribution of Cy5.5 Fluorescent Dye after Injection via the Lateral Ventricle and Cisterna Magna in Rat Model

OBJECTIVE: The purpose of this study was to find an optimal delivery route for clinical trials of intrathecal cell therapy for spinal cord injury in preclinical stage. METHODS: We compared in vivo distribution of Cy5.5 fluorescent dye in the spinal cord region at various time points utilizing in vivo optical imaging techniques, which was injected into the lateral ventricle (LV) or cisterna magna (CM) of rats. RESULTS: Although CM locates nearer to the spinal cord than the LV, significantly higher signal of Cy5.5 was detected in the thoracic and lumbar spinal cord region at all time points tested when Cy5.5 was injected into the LV. In the LV injection Cy5.5 signal in the thoracic and lumbar spinal cord was observed within 12 hours after injection, which was maintained until 72 hours after injection. In contrast, Cy5.5 signal was concentrated at the injection site in the CM injection at all time points. CONCLUSION: These data suggested that the LV might be suitable for preclinical injection route of therapeutics targeting the spinal cord to test their treatment efficacy and biosafety for spinal cord diseases in small animal models.

Glioblastoma specific antigens, GD2 and CD90, are not involved in cancer stemness / 대한해부학회지

Glioblastoma multiforme (GBM) is the most malignant World Health Organization grade IV brain tumor. GBM patients have a poor prognosis because of its resistance to standard therapies, such as chemotherapy and radiation. Since stem-like cells have been associated with the treatment resistance of GBM, novel therapies targeting the cancer stem cell (CSC) population is critically required. However, GBM CSCs share molecular and functional characteristics with normal neural stem cells (NSCs). To elucidate differential therapeutic targets of GBM CSCs, we compared surface markers of GBM CSCs with adult human NSCs and found that GD2 and CD90 were specifically overexpressed in GBM CSCs. We further tested whether the GBM CSC specific markers are associated with the cancer stemness using primarily cultured patient-derived GBM cells. However, results consistently indicated that GBM cells with or without GD2 and CD90 had similar in vitro sphere formation capacity, a functional characteristics of CSCs. Therefore, GD2 and CD90, GBM specific surface markers, might not be used as specific therapeutic targets for GBM CSCs, although they could have other clinical utilities.

Time-course analysis of DNA damage response-related genes after in vitro radiation in H460 and H1229 lung cancer cell lines

Radiation is the most useful treatment modality for cancer patients. It initiates a series of signal cascades such as DNA damage response (DDR) signaling for repairing damaged DNA, arresting the cell cycle, and inducing cell death. Until now, few genes have been found to be regulated by radiation, which explains the molecular mechanisms of cellular responses to radiation. Although the transcriptional changes caused by radiation have been widely investigated, little is known about the direct evidence for the transcriptional control of DDR-related genes. Here, we examined the radiosensitivity of two non-small cell lung cancer cell lines (H460 and H1299), which have different p53 status. We monitored the time-dependent changes of 24 DDR-related gene expressions via microarray analysis. Based on the basal expression levels and temporal patterns, we further classified 24 DDR-related genes into four subgroups. Then, we also addressed the protein levels of several DDR-related genes such as TopBP1, Chk1 and Chk2, confirming the results of microarray analysis. Together, these results indicate that the expression patterns of DDR-related genes are associated with radiosensitivity and with the p53 statuses of H460 and H1299, which adds to the understanding of the complex biological responses to radiation.

Immunohistochemical study on the expression of calcium binding proteins (calbindin-D28k, calretinin, and parvalbumin) in the cerebral cortex and in the hippocampal region of nNOS knock-out(-/-) mice / 대한해부학회지

Nitric oxide (NO) modulates the activities of various channels and receptors to participate in the regulation of neuronal intracellular Ca2+ levels. Ca2+ binding protein (CaBP) expression may also be altered by NO. Accordingly, we examined expression changes in calbindin-D28k, calretinin, and parvalbumin in the cerebral cortex and hippocampal region of neuronal NO synthase knockout(-/-) (nNOS-/-) mice using immunohistochemistry. For the first time, we demonstrate that the expression of CaBPs is specifically altered in the cerebral cortex and hippocampal region of nNOS-/- mice and that their expression changed according to neuronal type. As changes in CaBP expression can influence temporal and spatial intracellular Ca2+ levels, it appears that NO may be involved in various functions, such as modulating neuronal Ca2+ homeostasis, regulating synaptic transmission, and neuroprotection, by influencing the expression of CaBPs. Therefore, these results suggest another mechanism by which NO participates in the regulation of neuronal Ca2+ homeostasis. However, the exact mechanisms of this regulation and its functional significance require further investigation.

Immunohistochemical study on the expression of calcium binding proteins (calbindin-D28k, calretinin, and parvalbumin) in the cerebellum of the nNOS knock-out(-/-) mice / 대한해부학회지

Nitric Oxide (NO) actively participates in the regulation of neuronal intracellular Ca2+ levels by modulating the activity of various channels and receptors. To test the possibility that modulation of Ca2+ buffer protein expression level by NO participates in this regulatory effect, we examined expression of calbindin-D28k, calretinin, and parvalbumin in the cerebellum of neuronal NO synthase knock-out (nNOS(-/-)) mice using immunohistochemistry. We observed that in the cerebellar cortex of the nNOS(-/-) mice, expression of calbindin-D28k and parvalbumin were significantly increased while expression of calretinin was significantly decreased. These results suggest another mechanism by which NO can participate in the regulation of Ca2+ homeostasis.

Immunohistochemical Study on the Distribution of Glycogen Synthase Kinase (GSK) 3beta in the Central Nervous System of SOD1G93A Transgenic Mice / 체질인류학회지

In the present study, we investigated influences of glycogen synthase kinase (GSK) 3beta on the development and/or progression of amyotrophic lateral sclerosis (ALS). We used transgenic mice expressing a human Cu/Zn superoxide dismutase mutant (SOD1G93A) as an in vivo model of ALS and examined expressional changes of GSK3beta immunohistochemically in the spinal cord, brain stem and cerebellum. With these experiments we demonstrate that the neurons in these regions of symptomatic SOD1G93A transgenic mice showed increased GSK3beta immunoreactivities compared with wild-type SOD1 transgenic mice. In contrast to symptomatic SOD1G93A transgenic mice, few GSK3beta immunoreactivity changes were detected in 8w- and 13w-old presymptomatic SOD1G93A transgenic mice. These data suggest the possibility that GSK3 functions as a modulating factor of apoptosis-related alterations in ALS and that GSK3beta exert differential functions in the development and/or progression of ALS. But the exact functional significances of these changes require further elucidation.