Epigallocatechin-3-gallate ameliorates autoimmune arthritis by reciprocal regulation of T helper-17 regulatory T cells and inhibition of osteoclastogenesis by inhibiting STAT3 signaling

Lee, Seon-Yeong,Jung, Young Ok,Ryu, Jun-Geol,Oh, Hye-Jwa,Son, Hye-Jin,Lee, Seung Hoon,Kwon, Jeong-Eun,Kim, Eun-Kyung,Park, Mi-Kyung,Park, Sung-Hwan,Kim, Ho-Youn,Cho, Mi-La Society for Leukocyte Biology 2016 Journal of Leukocyte Biology Vol.100 No.3

<P>EGCG attenuates arthritis and osteoclastogenesis by inhibition of Th17 and reciprocal induction of T-reg. The green tea polyphenol epigallocatechin-3-gallate is a potent antioxidant. Here, we describe the effects of epigallocatechin-3-gallate on T cell differentiation and osteoclast differentiation in an animal model of arthritis. Mice with collagen-induced arthritis were injected intraperitoneally with epigallocatechin-3-gallate, 3 times/wk after the primary immunization. Surface markers of T helper 17 cells and regulatory T cells were analyzed by flow cytometry. Flow cytometry, Western blotting, and enzyme-linked immunosorbent assays were used to evaluate the effect of epigallocatechin-3-gallate on cell signaling in the collagen-induced arthritis model. Epigallocatechin-3-gallate decreased the arthritis index and showed protective effects against joint destruction in collagen-induced arthritis mice. The expression of cytokines, oxidative stress proteins, and phosphorylated-signal transducer and activator of transcription-3, 705 and 727, were significantly less in mice treated with epigallocatechin-3-gallate than it was in controls. Epigallocatechin-3-gallate reduced the expression of osteoclast markers in vitro and in vivo relative to the control, and the antiosteoclastic activity was observed in epigallocatechin-3-gallate-treated, interferon- knockout mice. The proportion of forkhead box protein 3-positive regulatory T cells was increased in the spleens of mice treated with epigallocatechin-3-gallate compared with control mice, whereas the proportion of T helper 17 cells was reduced. In vitro, the expression of nuclear respiratory factor 2, heme oxygenase-1, and extracellular signal-regulated kinase was increased significantly by epigallocatechin-3-gallate. We demonstrated that the administration of epigallocatechin-3-gallate attenuated the symptoms of arthritis, inhibited osteoclastogenesis and T helper 17 cell activation, and increased the number of regulatory T cells. At the molecular level, the antiarthritic effects of epigallocatechin-3-gallate may be due to induction of phosphorylated-extracellular signal-regulated kinase, nuclear respiratory factor 2, and heme oxygenase-1 and inhibition of signal transducer and activator of transcription-3 activation.</P>

녹차로부터 분리한 epigallocatechin-3-O-(3-O-methyl) gallate의 Helicobacter pylori 생육 억제 효과

반유진(Eu-Jin Ban),송은정(Eun-Jung Song),이동준(Dong-Jun Lee),문제학(Jae-Hak Moon),김선재(Seon-Jae Kim),박종환(Jong-Hwan Park),조정용(Jeong-Yong Cho) 한국차학회 2021 한국차학회지 Vol.27 No.1

Epigallocatechin-3-O-gallate (EGCG)는 차의 대표적인 유용성분 중 하나로, 항산화, 항암, 그리고 항염증등 다양한 건강기능성과 더불어 Helicobacter pylori의 생육을 억제하는 효과도 우수하다고 알려져 있다. 그러나, EGCG에 methyl기가 결합된 형태인 epigallocatechin-3-O-(3-O-methyl) gallate (EGCG3 Me)에 대한 H. pylori의생육 억제 효과는 보고된 바가 없다. 본 연구에서는 H. pylori P1WT 및 SS1 균주를 대상으로 차로부터 분리한EGCG3 Me의 항균 활성을 평가하였다. EGCG3 Me은 octadecylsilane-medium performance liquid chromatography를 이용하여 가루녹차(Camellia sinensis var. sinensis cv. Benifuuki)의 70% ethanol 추출물로부터분리되었으며, 그 구조는 ESI-MS, 1D-, 그리고 2D-NMR 분석을 통하여 확인되었다. 가루녹차로부터 분리된EGCG3 Me는 EGCG와 거의 유사하게 농도 의존적으로 H. pylori P1WT와 SS1 균주에 대한 생육 억제 효과를나타내었다. 특히, 두 균주 모두 50 그리고 100 μM의 EGCG 및 EGCG3 Me 처리에 의해 성장이 크게 억제되었으며, 100 μM 농도의 경우 P1WT와 SS1 균주의 성장을 매우 높은 수준으로 억제하였음을 관찰할 수 있었다. EGCG3 Me의 H. pylori 생육 억제 효과는 EGCG와 거의 유사하였다. 이상의 결과로부터 EGCG3 Me는 EGCG 와 더불어 H. pylori 생육 억제 효과를 갖는 차의 유용 소재로 활용이 기대된다. Epigallocatechin-3-O-gallate (EGCG), a major bioactive compound in green tea, has been shown to strongly inhibit the growth of Helicobacter pylori (H. pylori) apart from its other multiple health benefits. However, no study on the anti-Helicobacter pylori activity of epigallocatechin-3-O-(3-O-methyl) gallate (EGCG3 Me), a unique O-methylated form of EGCG, is currently available. The present study aimed to compare the growth inhibitory activities of EGCG and EGCG3 Me against H. pylori strains P1WT and SS1. EGCG3 Me was isolated from a 70% ethanol extract of green tea (Camellia sinensis var. sinensis cv. Benifuuki) by using octadecylsilane-medium performance liquid chromatography. Its structure was confirmed by ESI-MS and 1D- and 2D-NMR experiments. Both EGCG and EGCG3 Me inhibited the growth of H. pylori strains P1WT and SS1 in a dose-dependent manner. The antibacterial activity of EGCG3 Me was similar to that of EGCG. EGCG is well-known to be a potential anti-H. pylori agent. These results indicate that EGCG3 Me may be a valuable therapeutic agent against H. pylori infection.

Protective Effect of (-)-Epigallocatechin Gallate on Nitric Oxide-Induced Apoptosis in Alveolar Epithelial Cells

Cheon-Woong Choi,Jee-Hong Yoo,Sung-Eun Kim,Yun-Hee Sung,Jin-Hee Seo,Mal-Soon Shin,Dong-Hee Kim,Chang-Ju Kim 대한스트레스학회 2011 스트레스硏究 Vol.19 No.1

폐는 질소종류에 다양하게 반응한다. 폐 상피세포는 nitric oxide synthase (NOS)에 의해 L-아르기닌으로부터 합성된 유리기 무기물 가스인 산화질소에 민감하게 반응한다. 산화질소(nitric oxide)는 많은 생물학적 과정의 매개체이지만, 과도한 출현은 다양한 세포 유형의 세포사멸을 일으키기도 한다. 녹차의 주성분이며, 가장 풍부하게 들어있는 (-)-epigallocatechin-3-gallate (ECGC)는 최근에 세포사멸 경로를 조절하는 것으로 알려졌다. EGCG는 항산화, 항염증, 보호기전, 항세포사멸 효과를 보여주고 있다. 이에 본 연구에서는 인간 폐 상피세포에서 EGCG가 sodium nitroprusside (SNP)로 유도된 세포사멸에 대한 보호효과를 연구하였다. 인간의 폐포 유형 II L-132 세포를 가지고, EGCG의 항세포사멸을 확인하기 위해 MTT assay, DAPL staining, TUNEL assay, DNA fragmentation assay, Western blotting으로 분석하였다. 본 실험의 결과 SNP는 인간의 폐 상피 세포인 L-132에서 세포사멸의 형태학적 변화를 유발하였고, 세포사멸 전단계인 Bax 단백질의 발현을 증가시켰으며, caspase-3의 활성을 증가시켰다. 그러나 EGCE를 처치한 세포에서는 Bax 단백질의 발현을 감소하였고, 반 세포사멸 단백질인 Bcl-2의 발현은 현저하게 증가하여 caspase-3의 활성을 억제하는 결과를 확인하였다. 따라서 본 연구 결과 EGCG는 폐 상피 세포인 L-132에서 SNP로 유도된 세포사멸에 대한 보호 효과를 나타냄을 확인할 수 있었다. The lung is exposed to various stimulants, such as reactive nitrogen species. Alveolar epithelial cells are sensitive to nitric oxide (NO), which is a free radical inorganic gas synthesized from L-arginine by nitric oxide synthase (NOS). NO mediates many biological processes, but excessive NO exposure induces apoptosis in various cell types. (-)-Epigallocatechin-3-gallate (EGCG) has recently been shown to modulate apoptotic pathways. EGCG is the most abundant and most active ingredient of green tea. EGCG has been shown to have anti-carcinogenic, anti-oxidant, anti-inflammatory, neuroprotective, and anti-apoptotic effects. In the present study, we investigated whether EGCG exhibits a protective effect against apoptosis induced by the NO donor sodium nitroprusside (SNP) in human lung epithelial cells. To confirm the anti-apoptotic properties of EGCG, a 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, 4,6-diamidino-2-phenylindole (DAPI) staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay, DNA fragmentation assay, and Western blotting were performed using human alveolar type II L-132 cells. The present results show that SNP induced apoptotic morphological changes, increased the expression levels of the pro-apoptotic protein Bax and enhanced the enzymatic activity of caspase-3 in L-132 human lung epithelial cells. However, EGCG treatment remarkably increased the expression of the anti-apoptotic protein Bcl-2, decreased the expression of Bax, and suppressed the enzymatic activity of caspase-3. The results of the present study revealed that EGCG exerts a protective effect against SNP-induced apoptosis in L-132 human lung epithelial cells. (Korean J Str Res 2011;19:69∼77)

3T3-L1 세포에서 Resveratrol과 Epigallocatechin Gallate(EGCG)의 지방세포 분화 억제에 미치는 시너지 효과

김연정,곽호경,Kim, Yunjung,Kwak, Ho-Kyung 한국식품영양학회 2012 韓國食品營養學會誌 Vol.25 No.4

Resveratrol (RVT) and epigallocatechin gallate (EGCG) individually inhibit adipogenesis in 3T3-L1 adipocytes. The objective was to examine the possibility of interaction between RVT and EGCG, resulting in enhanced inhibition of adipogenesis in 3T3-L1 adipocytes. Preadipocytes were treated with RVT and EGCG individually at 6.25 or $25{\mu}M$ (RVT6.25 or RVT25) and 12.5 or $50{\mu}M$ (EGCG12.5 or EGCG50) and in combination (RVT6.25 + EGCG12.5 and RVT25 + EGCG50). RVT25 as an individual compound decreased lipid accumulation in 3T3-L1 adipocytes by 24%, and RVT25 + EGCG50 further decreased lipid accumulation by 77%. In addition, exposure of 3T3-L1 adipocytes to RVT6.25 + EGCG12.5 and RVT25 + EGCG50 combinations resulted in an enhanced increase of adiponectin release and inhibition of leptin release. Quantitative analysis revealed that the combination of tested materials (RVT6.25 + EGCG12.5 and RVT25 + EGCG50) decreased the expression levels of C/EBP${\alpha}$, PPAR${\gamma}2$, and aP2. These results indicate that the combined treatments with RVT and EGCG produce synergistic effects on inhibiting adipogenesis in 3T3-L1 adipocytes. The overall results suggested that the combining RVT and EGCG might be more capable of exerting antiobesity effects than each individual compound by itself.

녹차의 폴리페놀류인 에피갈로카테킨-3-갈레이트에 의한 항노화, 항비만 및 항암효과에 대한 비교 분석

임은지(Eun-Ji Lim),김민재(Min-Jae Kim),김현지(Hyeon-Ji Kim),이성호(Sung-Ho Lee),전병균(Byeong-Gyun Jeon) 한국생명과학회 2018 생명과학회지 Vol.28 No.10

본 연구에서는 다양한 사람의 암세포주(SNU-601, MKN74, AGS, MCF-7, U87-MG 및 A-549)와 정상세포주[MRC-5 섬유아세포, 사랑니 유래 중간엽 줄기세포(DSC), 3T3-L1 생쥐의 지방전구세포]에 녹차에 포함되어 있는 epigallocatechin-3-gallate (EGCG)를 처리하여 세포 증식, 세포 노화, 지방세포로의 분화, 말단소립복원효소 활성과 암세포의 전이 능력 등을 검증하여 항노화, 항비만 및 항암 효과를 서로 비교 조사하였다. MTT 분석에서 다양한 암세포주는 정상세포주보다 유의적으로 낮은 반억제농도값을 나타내었다. 10 uM의 EGCG가 포함된 배양액에서 정상체세포인 MRC-5와 DSC를 5 계대배양한 결과 세포증식 및 세포 노화에 큰 변화를 관찰하지 못하였고, 3T3-L1 생쥐의 지방전구세포를 지방분화 배양액에 EGCG를 첨가하여 지방세포로의 분화 억제를 유도하였지만 지방세포로의 분화를 역시 억제하지 못하였다. 그러나 여러 다양한 암세포주에 10 uM의 EGCG가 포함된 배양액에 배양한 결과 암세포의 세포증식 억제, 세포노화 유도, 말단소립복원효소 활성과 암세포의 전이 능력이 현저히 감소됨을 관찰하여 EGCG는 항노화나 항비만 효과보다는 항암효과에 더 효율적인 것으로 관찰되었고, 적당한 농도에서 잠재적인 항암물질로의 한 종류로 판단된다. The study compared the anti-aging, anti-adipogenesis, and anti-tumor effects of epigallocatechin-3-gallate (EGCG) in various cancer cell lines (SNU-601, MKN74, AGS, MCF-7, U87-MG, and A-549) and normal cell lines (MRC-5 fibroblasts, dental tissue-derived mesenchymal stem cells [DSC], and 3T3-L1 pro-adipocytes). Half inhibitory concentration (IC50) values were significantly (p<0.05) higher in normal cell lines (~50 uM), when compared to that in cancer cell lines (~10 uM). For anti-aging effects, MRC-5 and DSC were exposed to 10 uM EGCG for up to five passages that did not display any growth arrest. Population doubling time and senescence-related β-galactosidase (SA-β-gal) activity in treated cells were similar to untreated cells. For anti-adipogenic effects, mouse 3T3-L1 pre-adipocytes were induced to adipocytes in an adipogenic differentiation medium containing 10 uM EGCG, but adipogenesis in 3T3-L1 cells was not inhibited by EGCG treatment. For anti-tumor effects, the cancer cell lines were treated with 10 uM EGCG. PDT was significantly (p<0.05) increased in EGCG-treated SNU-601, AGS, MCF-7, and U87-MG cancer cell lines, except in MKN74 and A-549. The level of telomerase activity and cell migration capacity were significantly (p<0.05) reduced, while SA-β-gal activity was highly up-regulated in EGCG treated-cancer cell lines, when compared to that in untreated cancer cell lines. Our results have demonstrated that EGCG treatment induces anti-tumor effects more efficiently as noted by decreased cell proliferation, cell migration, telomerase activity, and increased SA-β-gal activity than inducing anti-aging and anti-adipogenesis. Therefore, EGCG at a specific concentration can be considered for a potential anti-tumor drug.

Using Resveratrol and Epigallocatechin-3-Gallate to Improve Cryopreservation of Stallion Spermatozoa With Low Quality

Nouri, Houshang,Shojaeian, Kamal,Samadian, Farhad,Lee, Soojung,Kohram, Hamid,Lee, Jeong Ik Elsevier 2018 Journal of equine veterinary science Vol.70 No.-

<P><B>Abstract</B></P> <P>Reactive oxygen species levels in semen with low quality increased from 25% to about 40%. Resveratrol (Res) is a natural grape-derived phytoalexin, and epigallocatechin-3-gallate (EGCG) is the major polyphenol in green tea (<I>Camellia sinensis</I>); both molecules are known to have high levels of antioxidant activity. The aim of this study was to investigate the effects of this antioxidant's supplementation on cryopreservation of stallion semen with poor quality. Experiment 1: Experiment design to asses stallions semen quality (n = 3). Arabian stallions were managed for breeding with fresh, extended, or chilled semen during 2 years (in two breeding season) with a resulting per cycle pregnancy rate (103/41 estrus cycle/conception) of 39.80%. A total of 81 ejaculates were collected and evaluated in fresh condition (total and progressive motility, membrane integrity, acrosome defects, morphology, and abnormal DNA condensation). Evaluation of several ejaculates revealed that sperm production and semen quality mostly did not change during the breeding season, maintaining normal sperm production with poor quality. Experiment 2: 18 ejaculates, collected with Missouri model artificial vagina from Arabian stallion (n = 3). Extended semen was centrifuged at 600 × g for 10 minutes. To eliminate individual stallion variability, the resulting sperm pellets were pooled and divided in seven different treatments in a final concentration of 100 × 10<SUP>6</SUP> sperm/mL by using semiskimmed milk extender containing no supplements (control), and the following supplements with three different concentrations: Res 5, 10, and 20 μM (Res 1, Res 2, Res 3, respectively) and EGCG 25, 50, 100 μM (EGCG 1, EGCG 2, and EGCG 3, respectively). After thawing, all samples were maintained at 37°C for 10 minutes. Evaluation of motility, plasma membrane integrity, viability, mitochondria activity, DNA fragmentation, and lipid peroxidation was determined. For all semen parameters, the lower concentration of Res (5 μM) and EGCG (25 μM) did not show significant differences compared to control (<I>P</I> > .05). Relative to the control group, Res 2 had better (<I>P</I> < .05) postthaw total and progressive motility, yet the higher concentrations (Res 3) showed a negative effect on total motility. Percentage of membrane integrity, viability, and mitochondrial activity was significantly greater in Res 2 and EGCG 2 extenders in comparison with the control group, respectively (<I>P</I> < .05). Results showed that malondialdehyde concentration was lower in Res 2 and EGCG 2 groups. In conclusion, the present study showed that the antioxidant Res prevents DNA damages in our stallions. The addition of Res and EGCG before cryopreservation can ameliorate mitochondrial activity in stallions with low-quality semen. Although further studies are needed, the present work showed that Res and EGCG could be considered as cryopreservation procedures in stallions with low-quality sperm and possibly equine, to avoid or minimize DNA damages, and preserve sperm plasma membrane integrity and mitochondrial activity.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The aim of this study was to investigate the effects of resveratrol (Res) and epigallocatechin-3-gallate (EGCG) supplementation on cryopreservation of stallion (n = 3) spermatozoa with poor quality. </LI> <LI> Five micromolar of Res and 50 μM EGCG in semiskimmed milk extender before cryopreservation can ameliorate total and progressive motility, percentage of membrane integrity, and viability in stallions with low quality. </LI> <LI> In conclusion, the present study showed that the 5 μM Res could prevent DNA damages in subfertile stallions. </LI> <LI> Although further studies are needed, the present work showed that Res and EGCG could be considered as cryopreservation procedures in stallions with low-quality sperm and possibly equine, to avoid or minimize DNA damag

Epigallocatechin-3-gallate, a green tea catechin, protects the heart against regional ischemia-reperfusion injuries through activation of RISK survival pathways in rats

Kim, Seok Jai,Li, Mei,Jeong, Cheol Won,Bae, Hong Beom,Kwak, Sang Hyun,Lee, Seong Heon,Lee, Hyun Jung,Heo, Bong Ha,Yook, Keun Bae,Yoo, Kyung Yeon 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.8

Epigallocatechin-3-gallate (EGCG), the major catechin derived from green tea, has been shown to modulate numerous molecular targets in the setting of inflammation. This study aimed to determine whether EGCG protects against regional myocardial ischemia/reperfusion (I/R) injuries and its underlying mechanisms involving the role of reperfusion injury salvage kinase (RISK) pathways (PI3K-Akt and ERK 1/2) and $GSK-3{\beta}$ or apoptotic kinases (p38 and JNK). The rats were subjected to I/R injuries consisting of 30 min ischemia followed by 2 h reperfusion. EGCG (10 mg/kg, intravenously) was administered alone or along with wortmannin (PI3K inhibitor, 0.6 mg/kg, intravenously) 5 min before the onset of reperfusion. Wortmannin was administered 10 min before the reperfusion. Infarct size was measured at the end of the reperfusion. The phosphorylation of Akt, $GSK-3{\beta}$, and MAPK kinases (ERK1/2, P38 and JNK) was determined by Western blotting after 10 min of reperfusion. EGCG reduced the infarct size compared with the control ($25.4{\pm}9.2$ versus $43.2{\pm}8.2$ %, p<0.05). Wortmannin alone did not affect the infarct size, but abolished the EGCG-induced infarct size limiting effect, indicating that EGCG may protect the heart by modulating the PI3K-Akt. EGCG significantly enhanced the phosphorylation of Akt and $GSK-3{\beta}$ but not ERK1/2, while it reduced that of p38 and JNK. These results suggest that EGCG has a protective effect against regional myocardial I/R injuries through activation of the RISK pathway and attenuation of p38 and JNK. EGCG may have cardioprotective effects in patients undergoing surgeries prone to myocardial I/R injuries.

(−)-epigallocatechin-3-gallate(EGCG)가 활성형 Akt를 유도하는 경로

김명진,김형일,김현철,정진,박혜련 대한구강악안면병리학회 2008 대한구강악안면병리학회지 Vol.32 No.1

The major component of green tea is (-)-epigallocatechin-3-gallate(EGCG) which accounts for 5080% of catechin, representing 200300 mg in a brewed cup of green tea. EGCG has been known to possess growth inhibitory and pro-apoptotic effect on human cancer cell lines such as prostate, bladder and breast cancers. In contrast, several studies have suggested that EGCG could promote cell proliferation and/or survival instead of pro-apoptotic effect. Understanding how intracellular signaling pathways respond to EGCG may provide a clue to the difference of cell responses and basis for usefulness of EGCG as a chemopreventive and/or chemotherapeutic agent. To better understand the mechanisms responsible for the chemopreventive efficacy of EGCG, the authors tried to identify the key molecules that contributes to Akt activation and can inhibit this activation. In the present study, EGCG increased Akt phosphorylation, an activeform of Akt and negatively affect on direct upstream molecules of Akt including PTEN and EGFR, though Akt phosphorylation was increased.

Autophagy inhibition contributes to epigallocatechin-3-gallate-mediated apoptosis in papillary thyroid cancer cells

Bu Ling,Zheng Tingting,Mao Chaoming,Fei Wu,Mou Xiao,Xu Chengcheng,Luo Xuan,Lu Qingyan,Dong Liyang,Wang Xuefeng 대한독성 유전단백체 학회 2021 Molecular & cellular toxicology Vol.17 No.4

Background Epigallocatechin-3-gallate is a natural polyphenolic compound that induces apoptosis in papillary thyroid cancer cells. However, its underlying molecular mechanism was not completely clarified. Objectives The present study demonstrated the role of apoptosis and autophagy in EGCG-treated papillary thyroid cancer cells and the relationship between these processes. Results EGCG significantly suppressed the viability of TPC-1 papillary thyroid cancer cells at an IC50 of 17.2 μM. EGCG induced TPC-1 cell apoptosis and cell cycle arrest at S phase and downregulated the protein expression of cyclin A and cyclin-dependent kinase-2. EGCG decreased reactive oxygen species levels, upregulated Bax expression, downregulated Bcl-2 expression and increased cytochrome C levels in the cytosol. Treatment with EGCG also increased the levels of cleaved caspase 3, cleaved caspase 9 and cleaved poly(ADP-ribose) polymerase. EGCG induced an autophagic response via the upregulation of the autophagy-related protein LC3-II and suppression of the AKT/mTOR signalling pathway. Autophagy inhibition further enhanced EGCG-induced cell apoptosis and ROS suppression, which indicated that autophagy played a cytoprotective role in EGCG-treated TPC-1 cells. Conclusion Taken together, these results demonstrated that autophagy inhibition was beneficial to EGCG–mediated apoptosis in papillary thyroid cancer cells. Background Epigallocatechin-3-gallate is a natural polyphenolic compound that induces apoptosis in papillary thyroid cancer cells. However, its underlying molecular mechanism was not completely clarified. Objectives The present study demonstrated the role of apoptosis and autophagy in EGCG-treated papillary thyroid cancer cells and the relationship between these processes. Results EGCG significantly suppressed the viability of TPC-1 papillary thyroid cancer cells at an IC50 of 17.2 μM. EGCG induced TPC-1 cell apoptosis and cell cycle arrest at S phase and downregulated the protein expression of cyclin A and cyclin-dependent kinase-2. EGCG decreased reactive oxygen species levels, upregulated Bax expression, downregulated Bcl-2 expression and increased cytochrome C levels in the cytosol. Treatment with EGCG also increased the levels of cleaved caspase 3, cleaved caspase 9 and cleaved poly(ADP-ribose) polymerase. EGCG induced an autophagic response via the upregulation of the autophagy-related protein LC3-II and suppression of the AKT/mTOR signalling pathway. Autophagy inhibition further enhanced EGCG-induced cell apoptosis and ROS suppression, which indicated that autophagy played a cytoprotective role in EGCG-treated TPC-1 cells. Conclusion Taken together, these results demonstrated that autophagy inhibition was beneficial to EGCG–mediated apoptosis in papillary thyroid cancer cells.

녹차(-)-Epigallocatechin-3-gallate 섭취가 고강도 운동시 흰쥐의 대장에서 HO-1발현에 미치는 영향

최석준 ( Suck Jun Choi ),이경완 ( Gyoung Wan Lee ) 대한스포츠의학회 2010 대한스포츠의학회지 Vol.28 No.1

The purpose of this study was to investigate effects of combined treatment with high intensity exercise and (-) epigallocatechin-3 gallate (EGCG), a potent free radical scavenger on a transcriptional level of hemoxygenase-1 gene in the large intestine. Sprague-Dawley rats were randomly divided into control group (CON, n=7), high intensity exercise group (HIE, n=7), EGCG group (EGCG, n=7), and EGCG plus high intensity exercise group (HIE+EGCG, n=7). Animals were given an intraperitoneal injection of EGCG with 50 mg of dosage per kg for four weeks 30 minutes before exercise. In order to induce HIE animals were allowed to ran on a treadmill with 0 degree of slope at speed of 28 m/min for 30 minutes. The exercise was performed four times a week for four week. The results of this study were as following; The expression level of hemoxygenase-1 mRNA of the high intensity exercise group was 15.21 times higher than that of the control group. The EGCG plus high intensity exercise group showed 5.98 times increased expression level of hemoxygenase-1 mRNA than control group. These results suggest that treatment of EGCG decrease the expression level of HO-1 mRNA through the removal of oxygen radicals produced by a high intensity exercise.