YoonYi Nam

Anti-hyperlipidemic effect of soybean extract fermented by Bacillus subtilis MORI in db/db mice

The purpose of this study was to investigate the anti-hyperlipidemic effect of soy bean extract solution fermented by Bacillus subtilis MORI (BTD-1E) in obese db/db mice. Eight-week-old male db/db mice were administered 33.3 mg/kg BTD-1E solution orally once a day for four weeks. The BTD-1E group showed significantly lower body weight compared with the db control group (P<0.05). The BTD-1E group showed significantly lower serum total cholesterol and LDL cholesterol levels compared with the db control group, respectively (P<0.05, P<0.01). The BTD-1E group showed significantly decreased liver weight relative to final body weight compared with the db control group (P<0.01). After four weeks of BTD-1E administration, lipid droplets in the liver were apparently decreased in the BTD-1E group compared to the db control group. In summary, our results suggest that BTD-1E has an anti-hyperlipidemic effect in the obese mouse model.

Silk fibroin has a protective effect against high glucose induced apoptosis in HIT‐T15 cells

High glucose levels induce cell death in many cell types, including pancreatic β‐cells. Although protective agents against glucotoxicity have been searched for extensively, so far none have been found. In this report, we tested silk fibroin (SF) as a candidate material for antiglucotoxicity in the pancreatic β‐cell (HIT‐T15 cell) line. Approximately 50% of cells were killed after treatment with 80 mg/mL glucose. This reduction of cell number was recovered by the addition of SF at 50 mg/mL. SF treatment also decreased cellular reactive oxygen species (ROS) and increased proliferating cellular nuclear antigen (PCNA) immunoreactivity. In addition, TUNEL assays demonstrated that SF protects against glucose‐induced apoptosis of HIT‐T15 cells, suggesting that SF might protect cells from cell death by lowering cellular ROS levels. SF also induced expression of the insulin‐like growth factor‐1 (IGF‐1) gene, and IGF‐1 expression may be the cause of SF‐induced protection against glucose toxicity. Taken together, these results suggest that SF could serve as a potential therapeutic agent to treat the hyperglycemia‐induced death of pancreatic β‐cells.

Expression of deafness protein Tmie in postnatal developmental stages of C57BL/6J mice

Loss-of function mutations in the transmembrane inner ear expressed (Tmie/TMIE) gene have been shown to cause deafness in mice and humans (DFNB6). Previous studies report that the circling mouse can be an animal model for DFNB6. However, the expression pattern of Tmie protein in postnatal developmental stages has not been clearly revealed. In this study we tried to investigate the expression of Tmie protein in the liver, spleen, kidney, and lung, as well as in the cochlea. We examined various tissue samples from five different age groups of C57BL/6J animals. Using western blotting analysis, the expression of Tmie protein in these organs has been identified. The results show that Tmie protein expression in the cochlea has been increased in postnatal developmental stages, indicating that Tmie plays an important role in not only the development and also in the function of the cochlea. The expression pattern of Tmie in adult mouse organs such as the liver, spleen, kidney, and spleen significantly vary in adult rats. The order of Tmie expression level in mice (63 days after birth) was spleen, liver, lung, cochlea, and kidney, whereas in the adult rat it was liver, cochlea, lung, spleen, and kidney.

Mapping of the Faded (fe) Gene to a Region between D10mit191 and D10mit44 on Mouse Chromosome 10

The faded mouse is a coat color mutant that shows faded coat color and age-related loss of pigmentation. This mutation is transmitted by an autosomal recessive gene with 100% penetrance. In the present study, we carried out linkage analysis of the faded (fe) gene using intra-specific backcross panels. Affected faded mice were carefully confirmed by their faded coat color at about 4 weeks of age. In the intra-specific backcross between faded and CBA mice (n=198), the fe gene was mapped to a region 2.1 cM distal to D10mit191. Therefore, the gene order was defined as follows: centromere-D10mit51 (12.4±2.4 cM)-D10mit191 (2.1±1.0 cM)-fe-D10mit44 (13.3±2.4 cM)-D10mit42 (14.4±2.5 cM). This linkage map of the fe locus will provide a good entry point to isolate the fe gene. Since the faded mouse has pigmentary abnormalities, this mutant may be a useful model for studies of pigmentary abnormalities in humans.