Beom-Jun Lee

Spatiotemporal expression of the selenoprotein P genein postimplantational mouse embryos

Selenoprotein P (Sepp) is an extracellular glycoprotein which functions principally as a selenium (Se) transporter and antioxidant. In order to assess the spatiotemporal expression of the Sepp gene during mouse embryogenesis, quantitative RT-PCR and in situ hybridization analyses were conducted in embryos and extraembryonic tissues, including placenta. Sepp mRNA expression was detected in all embryos and extraembryonic tissues on embryonic days (E) 7.5 to 18.5. Sepp mRNA levels were high in extraembryonic tissues, as compared to embryos, on E 7.5-13.5. However, the levels were higher in embryos than in extraembryonic tissues on E 14.5-15.5, but were similar in both tissues during the subsequent periods prior to birth. According to the results of in situ hybridization, Sepp mRNA was expressed principally in the ectoplacental cone and neural ectoderm, including the neural tubes and neural folds. In whole embryos, Sepp mRNA was expressed abundantly in nervous tissues on E 9.5-12.5. Sepp mRNA was also expressed in forelimb and hindlimb buds on E 10.5-12.5. In the sectioned embryos, on E 13.5-18.5, Sepp mRNA was expressed persistently in the developing limbs, gastrointestinal tract, nervous tissue, lung, kidney and liver. On E 16.5-18.5, Sepp mRNA expression in the submandibular gland, whisker follicles, pancreas, urinary bladder and skin was apparent. In particular, Sepp mRNA was detected abundantly in blood cells during all the observed developmental periods. These results show that Sepp may function as a transporter of selenium, as well as an antioxidant, during embryogenesis.

Differential expression of gastrointestinal glutathione peroxidase (GI-GPx) gene during mouse organogenesis.

With 4 figures and 1 table

Protective effects of cultured and fermented ginseng extracts against scopolamine-induced memory loss in a mouse model

This study was performed to investigate the effect of a concentrate of fermented wild ginseng root culture (HLJG0701) on memory improvement in the scopolamine (SPL)-induced memory-deficient mouse model. Eight-week-old male ICR mice were used to evaluate the protective effect of HLJG0701 against the SPL-induced memory loss animal model. The Morris water maze test, which measures hippocampus-dependent learning ability, and the Y-maze test, a short-term memory assessment test, were performed and related markers were analyzed. HLJG0701-treated groups displayed significantly reduced acetylcholinesterase activity and increased acetylcholine level compared with the SPL-administered group (SPL-G) (P<0.05). In the Y-maze test, the spontaneous alternation in al HLJG0711-treated groups was significantly increased compared with that in SPL-G (P<0.05). In the Morris water maze test, the escape latency and time spent in the target quadrant in all HLJG0701-treated groups were significantly decreased and increased, respectively, compared with those in SPL-G (P<0.05). In addition, the brain-derived neurotrophic factor level in groups treated with HLJG0701 300 and 600 mg/kg body weight was significantly increased compared with that in SPL-G (P<0.05). These results suggest that the HLJG0701 may protect against memory loss by inhibiting acetylcholinesterase activity and preventing acetylcholine deficiency.

The effect of near-infrared fluorescence conjugation on the anti-cancer potential of cetuximab

This study investigated the anti-cancer potential of a near-infrared fluorescence (NIRF) molecule conjugated with Cetuximab (Cetuximab-NIRF) in six-week-old female BALB/c athymic (nu+/nu+) nude mice. A431 cells were cultured and injected into the animals to induce solid tumors. Paclitaxel (30 mg/kg body weight (BW)), Cetuximab (1 mg/kg BW), and Cetuximab-NIRF (0.25, 0.5 and 1.0 mg/kg BW) were intraperitoneally injected twice a week into the A431 cell xenografts of the nude mice. Changes in BW, tumor volume and weight, fat and lean mass, and diameter of the peri-tumoral blood vessel were determined after two weeks. Tumor volumes and weights were significantly decreased in the Cetuximab-NIRF (1 mg/kg BW) group compared with the control group (P<0.001). Lean mass and total body water content were also conspicuously reduced in the Cetuximab-NIRF (1 mg/kg BW) group compared with the vehicle control group. Peri-tumoral blood vessel diameters were very thin in the Cetuximab-NIRF groups compared with those of the paclitaxel group. These results indicate that the conjugation of Cetuximab with NIRF does not affect the anti-cancer potential of Cetuximab and NIRF can be used for molecular imaging in cancer treatments.