3T3-L1 지방세포 및 제2형 당뇨 마우스 모델에서 건지황 열수 추출물의 항당뇨 효능 연구

국문 초록 (Abstract)

본 연구에서는 대표적인 한의서인 동의보감 및 방약합편에 수재된 농식품 소재 중 당뇨병과 같은 대표증상에 효과가 있는 것으로 소개된 건지황에 대해 3T3-L1 지방세포와 제 2형 당뇨질환모델인 C57BLKsJ-db/db 마우스에서 항당뇨 효과를 조사하였다. 건지황 열수 추출물을 제조하여 3T3-L1 지방세포에서 포도당 흡수능을 관찰한 결과, 3T3-L1 지방세포의 인슐린 감수성을 향상시켜 세포 내로의 포도당 흡수를 대조군 대비 약 2배 증가시켰다. 제2형 당뇨모델인 C57BLKsJ-db/db 마우스에 양성치료약물인 metformin(300 mg/kg bw/d), pioglitazone(20 mg/kg bw/d)과 건지황 열수 추출물(50, 500 mg/kg bw/d)을 4주간 각각 경구 투여한 후 항당뇨 효능을 평가한 결과, 체중감소량의 변화 없이 식이섭취량 및 음수섭취량이 감소하는 경향을 나타내었다. 공복혈당 및 HbA1c 수준은 건지황 열수 추출물을 투여했을 때 당뇨대조군에 비하여 유의적으로 감소시켰지만 경구 내당능은 당뇨대조군에 비하여 유의한 차이는 없었지만 개선하는 경향이 있었다. 혈중 인슐린 및 HOMA-IR 수준은 당뇨대조군에 비해 양성대조군 및 건지황 투여군에서 현저하게 낮은 수치를 나타내었으며, 혈중 중성지방 및 HDL-콜레스테롤 함량은 당뇨대조군에 비해 유의한 변화는 없었지만 총 콜레스테롤 농도는 유의한 감소를 나타내었다. 또한 조직에서 GCK mRNA 및 SLC2A2 mRNA 발현 정도가 유의적으로 증가하였으며, 특히 RG 500 mg/kg bw 투여군에서 제2형 당뇨병의 치료제인 Met 투여군과 비슷한 수준의 GCK 증가 효과가 확인되었다. 이러한 결과로 건지황 열수 추출물은 당뇨 증상 중 음수량, 음수횟수 증가 등을 완화시키고 지질대사 이상을 조절하면서 인슐린저항성을 감소시켜 혈당을 개선하므로 항당뇨 생리활성을 나타내는 식품소재로써 당뇨 개발의 가능성이 있을 것으로 사료되었다.

다국어 초록 (Multilingual Abstract)

Type 2 diabetes mellitus is characterized by a clinical disorder of sugar and fat metabolism caused by cellular insulin resistance. In our study, the anti-diabetic effects of water extract of Rehmannia glutinosa Libosch (RG) root (40, 200, 1,000 μg/mL) were investigated in mature 3T3-L1 adipocytes. RG root was found to increase glucose uptake under insulin (1 μM)-stimulation conditions but had no effects on glucose uptake without insulin in 3T3-L1 adipocytes. Additionally, the anti-diabetic effects of RG root were studied in a diabetes mellitus animal model (C57BL/KsJ-db/db) by oral ingestion of RG for 4 weeks (50, 500 mg/kg bw/d). During the experimental period, food intake, body weight, and fasting blood glucose level were measured every week. At the end of the treatment, oral glucose tolerance, blood glucose level, HbA1c, plasma insulin level, and blood profile parameters, including AST, ALT, TG, total and HDL-cholesterol levels, were measured. Treatment with RG root resulted in a lower blood glucose level, HbA1c, total cholesterol, ALT, oral glucose tolerance, and serum insulin levels. The mRNA expression of glucokinase (GCK) and solute carrier family 2 (SLC2A2) was significantly increased in liver tissue were reduced by water extract of RG. These results explains the anti-type 2 diabetic effects of water extract of RG.

목차 (Table of Contents)

• ABSTRACT
• 서론
• 재료 및 방법
• 결과 및 고찰
• 요약
• REFERENCES

참고문헌 (Reference)

1 강병일, "혈액투석으로 성공적으로 치료한 메포르민 유산산증 2예" 대한내과학회 80 (80): 473-476, 2011

2 이소영, "제2형 당뇨 모델 KK-Ay 마우스에 대한 발효 녹차의 항당뇨 효과" 한국식품과학회 45 (45): 488-494, 2013

3 강영선, "당뇨신병증의 최신 치료" 대한내과학회 90 (90): 402-405, 2016

4 Im SS, "Transcriptional regulation of glucose sensors in pancreatic beta cells and liver" 2 : 11-18, 2006

5 Thorens B, "The loss of GLUT2 expression by glucose-unresponsive beta cells of db/db mice is reversible and is induced by the diabetic environment" 90 : 77-85, 1992

6 Deng YT, "Suppression of free fatty acid-induced insulin resistance by phytopolyphenols in C2C12 mouse skeletal muscle cells" 60 : 1059-1066, 2011

7 Iynedjian PB, "Stimulation by insulin of glucokinase gene transcription in liver of diabetic rats" 263 : 740-744, 1988

8 Rencurel F, "Requirement of glucose metabolism for regulation of glucose transporter type 2 (GLUT2) gene expression in liver" 314 : 903-909, 1996

9 Oliveira CP, "Removal from the plasma of the free and esterified forms of cholesterol and transfer of lipids to HDL in type 2 diabetes mellitus patients" 11 : 65-, 2012

10 김석희, "Rehmanniae Radix, an Effective Treatment for Patients with Various Inflammatory and Metabolic Diseases: Results from a Review of Korean Publications" 대한약침학회 20 (20): 81-88, 2017

11 Zhang RX, "Rehmannia glutinosa: review of botany, chemistry and pharmacology" 117 : 199-214, 2011

12 Nugent C, "Potentiation of glucose uptake in 3T3-L1 adipocytes by $PPAR{\gamma}$ agonists is maintained in cells expressing a $PPAR{\gamma}$ dominant-negative mutant: evidence for selectivity in the downstream responses to $PPAR{\gamma}$ activation" 15 : 1729-1738, 2001

13 Laukkanen O, "Polymorphisms in the SLC 2A2 (GLUT2) gene are associated with the conversion from impaired glucose tolerance to type 2 diabetes" 54 : 2256-2260, 2005

14 Silva VM, "Plasma lipids, lipoprotein metabolism and HDL lipid transfers are equally altered in metabolic syndrome and in type 2 diabetes" 49 : 677-684, 2014

15 Altaf QA, "Novel therapeutics for type 2 diabetes: insulin resistance" 17 : 319-334, 2015

16 Pernicova I, "Metformin-mode of action and clinical implications for diabetes and cancer" 10 : 143-156, 2014

17 Kahn SE, "Mechanisms linking obesity to insulin resistance and type 2 diabetes" 444 : 840-846, 2006

18 Zhang J, "Identification of suitable reference genes for quantitative RT-PCR during 3T3-L1 adipocyte differentiation" 33 : 1209-1218, 2014

19 Jacobson PB, "Hepatic glucocorticoid receptor antagonism is sufficient to reduce elevated hepatic glucose output and improve glucose control in animal models of type 2 diabetes" 314 : 191-200, 2005

20 Agius L, "Glucokinase and molecular aspects of liver glycogen metabolism" 414 : 1-18, 2008

21 Ohneda M, "GLUT2 expression and function in beta-cells of GK rats with NIDDM. Dissociation between reductions in glucose transport and glucose-stimulated insulin secretion" 42 : 1065-1072, 1993

22 임순성, "Fermentation of purple Jerusalem artichoke extract to improve the α-glucosidase inhibitory effect in vitro and ameliorate blood glucose in db/db mice" 한국영양학회 10 (10): 282-287, 2016

23 Ahn SW, "Enhancement of alcohol fermentation yield by adding the extract of dried Rehmannia glutinosa Liboschitz" 8 : 351-361, 2000

24 Ren L, "Effects of water extracts of Rehmannia glutinosa on antioxidant system of Nrf2 in paraquat-induced insulin resistance diabetic rat model" 14 : 5847-5850, 2017

25 Xiao CC, "Effects of pioglitazone and glipizide on platelet function in patients with type 2 diabetes" 19 : 963-970, 2015

26 Lee SH, "Effects of brown alga, Ecklonia cava on glucose and lipid metabolism in C57BL/KsJ-db/db mice, a model of type 2 diabetes mellitus" 50 : 575-582, 2012

27 Seo KI, "Effect of curcumin supplementation on blood glucose, plasma insulin, and glucose homeostasis related enzyme activities in diabetic db/db mice" 52 : 995-1004, 2008

28 Salomaki H, "Correction: Prenatal metformin exposure in mice programs the metabolic phenotype of the offspring during a high fat diet at adulthood" 8 : 1-10, 2013

29 Ahn SW, "Comparison of biological activities on Rehmannia Radix and R. Radix preparata produced in Korea" 7 : 257-262, 1999

30 Oh HL, "Characteristics and antioxidant activities of Rehmannia radix powder" 42 : 62-67, 2002

31 Cheng S, "Calcitriol reduces hepatic triglyceride accumulation and glucose output through $Ca^{2+}/CaMKK{\beta}/AMPK$ activation under insulin-resistant conditions in type 2 diabetes mellitus" 16 : 747-758, 2016

32 이연리, "C57BL/KsJ-db/db 제2형 당뇨병 마우스에서 발아일품벼 추출물의 항당뇨효과" 한국식품영양과학회 41 (41): 339-344, 2012

33 김민아, "C57BL/6J Mice에서 단백다당체 함유 차가버섯 균사체의 지질개선 및 혈당조절효과" 한국식품영양과학회 38 (38): 667-673, 2009

34 Stratton IM, "Association of glycaemia with macrovascular and microvascular complications of type 2 diabetes (UKPDS 35): prospective observational study" 321 : 405-412, 2000

35 김혜정, "Antidiabetic, Antioxidative and Renoprotective Effects of Rehmanniae Radix preparata Extract in Streptozotocin-induced Diabetic Rats" 대한의생명과학회 14 (14): 19-26, 2008

36 Zhu H, "Antidiabetic and antioxidant effects of catalpol extracted from Rehmannia glutinosa (Di Huang) on rat diabetes induced by streptozotocin and high-fat, highsugar feed" 11 : 25-, 2016

37 Lee IS, "Anti-diabetic and anti-obesitic effects of aqueous extracts of Yangkyuksanhwa-tang and its two major compositions on db/db mice" 83 : 431-438, 2016

38 Yabe D, "${\beta}$ Cell dysfunction versus insulin resistance in the pathogenesis of type 2 diabetes in East Asians" 15 : 602-, 2015