Recombinant thymosin β4 (rTβ4) has been reported to migrate and promote vascularization, wound-healing, and hair growth in a mouse hindlimb ischemia model of peripheral vascular disease. C57BL/6 mice (11-weeks-old) were anesthetized and an ischemic model was made by cutting the right aorta femoralis. The ischemic group was intraperitoneally administered with saline (300 μL/mouse) and the muscular administration group received rTβ4 (150 μg in 300 μL of saline) or rTβ4 (150 μg in 300 μL saline) to the abdominal cavity at 3-day intervals for 21 days. Myoatrophy of the ischemic group was observed compared to the normal control group. Generation of adjacent vessels was carried out in the rTβ4 administration group compared to the ischemic group. The biopsy results showed significant fibrosis around the muscular undersurface and perimysium in the musculus quadriceps femoris of the ischemic group, whereas partial fibrosis was observed in the perimysium and endomysium in the rTβ4 administration group. Immunostaining indicated that expression levels of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor-1 (VEGF-1), and endothelial nitric oxide synthase (eNOS) in the rTβ4 group were higher than those of the ischemic group. Western blotting showed that expression levels of HIF-1α, VEGF-1, and eNOS in the rTβ4 group were higher than those of the ischemic group. In conclusion, rTβ4 increases expression levels of HIF-1α, VEGF-1, and eNOS, resulting in angiogenesis.
본 연구는 동충하초(Isaria tenuipes)를 유전적 당뇨 질환 동물모델인 OLETF 랫드에서 4주간 경구 투여하여 항당뇨 효과에 대한 연구결과로써, OLETF 랫드 동충하초(Isaria tenuipes) 투여군은 당뇨대조군과 비교하여 투여 4주에는 사료 섭취량과 체중이 증가하였다. 이는 동충하초(Isaria tenuipes)를 섭취한 OLETF 랫드는 고지방식 사료만 섭취 한 OLETF 랫드에 비해 당뇨 유발이 개선된 결과로 판단 된다. 혈중 포도당 농도, 인슐린 농도 및 인슐린 저항성 지표인 HOMA-IR 수치가 용량 의존적으로 감소하였다. 또한 GLUT4 유전자 발현을 측정한 결과 대조군에 비해 동충 하초(Isaria tenuipes) 투여군의 mRNA 및 단백질이 용량의존적으로 증가하는 경향을 보였다. 따라서, 동충하초 (Isaria tenuipes)의 섭취가 제2형 당뇨에서 인슐린의 감수성이나 저항성에 영향을 미치고, 혈당을 강화시키는 것으로 사료되므로 당뇨병환자의 혈당저하에 기여할 것이라 기대한다. 이에 본 연구는 천연물질을 이용한 당뇨병의 예방 및 치료에 동충하초(Isaria tenuipes)를 사용할 수 있는 이론적 토대를 제공할 것으로 생각된다.
Stevioside, a natural sweeteners presently used in various kinds of food and food products in Korea, was evaluated for its toxicity potential in the 14 day feeding study using B6C3F1 mice. Stevioside was added to the diet at different concentrations of 0.31, 0.62, 1.25, 2.5 and 5%, and was administered for 14 consecutive days. An increase of liver organ weight in male mice was observed. No diet-related differences were noted in clinical signs, food consumption, and gross and histopatholgical evaluation. Based on these results, we concluded that the concentration of 5% in the diet was a suitable maximum tolerable dose of stevioside for a 90 day study in mice.