• Toxicological Research
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• 제9권2호
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• pp.177-186
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• 1993

Previous results from several laboratories have demonstrated that tumor necrosis factor-alpha (TNFalpha) depressed cytochrome P-450 (P-450)-dependent drug metabolism in vivo. However, there is some debate whether the action of TNFalpha is mediated by its direct effects on hepatocytes, or is indirectly mediated through the release of other mediators like IL-1 from macrophages. In the present studies, we investigated the effects of TNFalpha on P-450-dependent drug metabolizing enzyme as measured by 7-ethoxyresorufin O-deethylase (EROD) activity.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 1990년도 Proceedings of International Symposium on Korean Ginseng, 1990, Seoul, Korea
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• pp.58-64
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• 1990

The effects of ginseng saponins, G-Rbl and G-Rc on the rat liver LDH A-gene transcnptional activity was investigated during pro-replicative phase of rat liver after partial hepatectomy. Changes in LDH A-mRNA levels in regenerating rat liver after intraperitoneal administrations of G-Rbl of G-Rc were tested by slot blot hybridization methods. The results showed that G-Rbl (1 mg/100g B.W) and G-Rc (1 ma/100g B.W) caused marked increases of LDH A-mRNA contents by respectively 1.9- and 1.5-fold in rat liver at 5·hours after partial hepatectomy. Dose dependent effect of G-Rbl and G-Rc (1-25 mg/100g B.W) on the LDH A-mRNA levels on regenerating rat liver were also analyzed. The maximal in- creases of liver LDH A-mRNA levels were observed with the doses of 1 mg for G-Rbl and 5 mg for G-Rc However, when the administration doses of G-Kbl and G-Rc were increased to 20 mg, G-Rbl caused a marked decrease of LDH A-mRNA level to 61% of those in sham-operated rat liver In contrast, G-Rc slightly decreased the liver LDH A-mRNA contents by 30% as compared to those of the maximum value but still maintained 22% higher LDH A-mRNA levels then those of sham-operated rate liver. On the basis of these experimental results, we conclude that ginseng saponin, G-Rb 1 and G·Rc have stimulatory effect at the lower concentration (1 mg/100g B.W) and inhibitory effect at the higher concentration (20 moi loos 5.W) on the LDH A-gene transcription during regeneration of rat liver, Additionally we also investigated the stimulatory effects of ginsenosides on the protein and DNA synthetic activities in hepatocyte primary cell cultures isolated from regenerating rat liver. Both of G·Rc and -Re increased the synthetic rates of hepatocytes proteins and DNA at the administration doses of 50 ug and 100 ug/3 ml/dish respectively representing 1.3-1.6 fold increases. From these results we postulate that G-Rc and -Re may have a mitogen enhancer activity for the hepatocyte proliferation during rat liver regeneration period. Keywords Inductive effects of ginsenosides, G-Rb, -Rc, and -Re, rat LDH A-gene transcription, the sin thetic rate of proteins and DNA in regeneration rat liver.

• Journal of Ginseng Research
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• 제14권2호
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• pp.200-206
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• 1990

The effects of ginseng saponins, SRbl and G-Rc on the rat liver LDH A-gene transcriptional activity was investigated during prereplicative phase of rat liver after partial hepatectomy. Changes in LDH A-mRNA levels in regenerating rat liver after intraperitoneal administrations of G-Rbl or 'G-Rc were tested by slot blot hybridization methods. The results showed that G-Rbl (1 mg/100g B.W) and G-Rc (1 mg/100g B.W) caused marked increases of LDH A-mRNA contents by respectively 1.9- and 1.5-fold in rat liver at 5-hours after partial hepatectomy Dose dependent elect of G-Rbl and G-Rc (1-25 mg/ 100g B.W) on the LDH A-mRNA levels on regenerating rat liver were also analyzed. The maximal increases of liver LDH A-mRNA levels were observed with the doses of 1 mg for G-Rbl and 5 mg for G-Rc. However, when the administration doses of G-Rbl and G-Rc were increased to 20 mg, G-Rbl caused a marked decrease of LDH A-mRNA level to 61% of those in sham-operated rat liver. In contrast, G-Rc slightly decreased the liver LDH A-mRNA contents by 30% as compared to those of the maximum value but still maintained 22% higher LDH A-mRNA levels then those of sham-operated rate liver. On the basis of these experimental results, we conclude that ginseng saponin, G-Rbl and G-Rc have stimulatory effect at the lower concentration (1 mg/ 100g B.W) and inhibitory effect at the higher concentration (20 mg/ 100g B.W) on the LDH A-gene transcription during regeneration of rat liver. Additionally we also investigated the stimulatory effects of ginsenosides on the protein and DNA sinthetic activities in hepatocyte primary cell cultures isolated from regenerating rat liver. Both of G-Rc and -Re increased the synthetic rates of hepatocytes proteins and DNA at the administration doses of 50 us and 100 $\mu\textrm{g}$/3 ml/dish respectively representing 1.3-1.6 fold increases. From these results we postulate that G-Rc and -Re may have a mitogen ehincer activity for the hepatocyte proliferation during rat liver regeneration period.

• 한국약용작물학회지
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• 제8권2호
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• pp.157-164
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• 2000

활성산소에 기인하는 다양한 성인병을 예방 치료할 수 있는 안전하고 우수한 항산화 물질을 천연물로 부터 개발하기 연구의 일환으로 오배자의 주성분에 대한 항산화효과 및 간보호효과를 연구하여 다음과 같은 결과를 얻었다. 1. Ferric-Thiocyanate 법에 의하여 과산화반응 억제에 따른 항산화 활성을 측정한 결과 모두 tocopherol보다 강한 과산화반응 억제 활성을 보였으며 gallic acid methyl ester, protocatechuic acid와 syringic acid는 tocopherol 보다는 강한 활성을 보였으며 BHA와는 유사 또는 그 이상의 활성을 보였다. 특히 1, 2, 3, 4, $6-penta-O-galloyl-{\beta}-D- glucose$는 tocopherol과 BHA보다 매우 강한 과산 화반응억제 활성을 보였다. 2. TBA 법에 의한 과산화지질의 생성의 지표인 MDA 억제효과에 의한 항산화효과를 측정한 결과 gallic acid 는 $1.6{\times}10^{-4}$의 농도에서 BHA 보다 높은 억제율을, protocatechuic acid는 $1.6{\times}10^{-6}$의 농도에서 BHA 보다 높은 억제율을 보였다. gallic acid methyl ester와 1, 2, 3, 4, $6-penta-O-galloyl-{\beta}-D-glucose$는 농도가 증가함에 따라 우수한 MDA의 억제활성을 나타내었다. 3. Glycyrrhizin을 비교군으로 하여 간 보호 실험을 한 결과 1, 2, 3, 4, $6-penta-O-galloyl-{\beta}-D-glucose$의 0.5mg/ml첨가군에서는 GOT의 강한 감소 효과를 보였으며 GPT 실험에서는 각 시료 0.5mg/ml 첨가군에서 감소하는 경향을 나타내었다.

• 한국식품영양과학회지
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• 제33권8호
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• pp.1246-1251
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• 2004

본 실험은 사염화탄소 독성에 대한 몇 가지의 식물소재들- 솔잎, 콩나물, 인진쑥, 표고버섯 - 의 간보호 효과를 조사하기 위하여 수행되었다. 우선적으로 일차 간세포 배양실험에서 식물추출물(열수 또는 에탄올)을 첨가(20 mg/mL 배지)하고 2시간 후에 사염화탄소를 처리(50$\mu$L)한 결과, 배지내의 AST와 ALT 효소활성은 다음과 같았다. 솔잎은 에탄올 및 열수 추출물(P<0.05)에서, 표고버섯은 열수 추출물(p<0.01∼0.05)에서, 그리고 콩나물과 인진쑥은 추출방법에 따라 유의성 있는(p<0.01) 감소를 보였다. 또한, 3주간의 식물 추출물을 첨가한 사료를 사전급여하고 사염화탄소를 2일간 복강주사(1 mg/kg 체중)한 동물실험에서 혈청내의 AST 및 ALT 활성은 간세포 배양의 결과와 유사하게 솔잎과 콩나물에서 낮은 활성효과(p<0.01)를 보였다. 정상군에 대한 사염화탄소의 투여는 지질과산화물과 cytochrome P-450의 함량, 그리고 xanthine oxidase(XOD) 활성을 크게 증가시켰다. 그러나 식물소재 중에서 솔잎, 콩나물, 인진쑥 등을 추출물을 첨가한 실험군에 대한 사염화탄소 처리는 일반적으로 지질과 산화와 XOD 활성증가를 억제하는 것(p<0.01)으로 나타난 반면에, cytochrome P-450의 함량 증가는 솔잎과 인진쑥의 첨가군에서 관찰되었다. 따라서 본 실험에서 cytochrome P-430의 함량증가에 대한 식물 추출물들의 효과는 확실하지 않았지만, 솔잎과 콩나물의 추출물은 항산화관련 실험에서 대부분 탁월한 효과를 나타내었다.

• Toxicological Research
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• 제22권1호
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• pp.23-30
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• 2006

Among poly aromatic hydrocarbons, dioxin and PCBs are the most controversial environmental pollutants in our modern life. These pollutants are known as human carcinogens, and liver is the most sensitive target in animal cancer models. Specific aims of the study were focused on the mechanism of carcinogenesis in hepatocytes and the structure-activity relation among these diverse environmental chemicals. Because key mechanisms of dioxin-induced carcinogenesis in human epithelial cell model are the alteration of signal transduction pathway and PKC isoforms, the alteration of the signal transduction pathways and other factors associated with carcinogenesis were studied. Rat hepatocytes cultured under the sandwich protocols were exposed with the various concentration of dioxins and PCBs, and signal transduction pathway, protein kinase C isoforms, oxidant stress, and apoptotic nuclei were evaluated. Since it is important to understand the structure-activity relation among these chemicals to properly assess the carcinogenic potentials, the study analyzed the parameters associated with carcinogenic processes, based on their structural characteristics. In addition, signal transduction pathways and PKC isoforms involved in inhibition of UV-induced apoptosis were also analyzed to elaborate the tumor promotion mechanism of these chemicals. Induction of apoptosis by UV irradiation was optimal at $60\;J/m^2$ in primary hepatocyte in culture. Compared to non coplanar PCBs such as PCB 114 and PCB 153, coplanar PCBs such as PCB 77 and PCB126 showed a stronger inhibition of apoptosis induced by UV irradiation. Production of reactive oxygen species (ROS) was more stimulated by non-coplanar PCBs than coplanar PCBs with the most potent induction of ROS by chlorinated non-coplanar PCB. As compared to the level of induction by PCB126, non-coplanar PCB153 showed a higher increase of intracellular concentrations. Besides the alteration of intracellular calcium concentration, translocation of PKC from cytosolic fraction to membrane fraction was clearly observed upon the exposure of non-coplanar PCB. Taken together, the present study demonstrated that there is a potent structure-activity relationship among PCB congeners and the mechanism of PAH-induced carcinogenesis is structure-specific. The study suggested that more diverse pathways of PAH-induced carcinogenesis should be taken into account beyond the boundary of Ah receptor dogma to assess the health impact of PAH with more accuracy.

• Genomics & Informatics
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• 제8권1호
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• pp.41-49
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• 2010

Statins are competitive inhibitors of hydroxy-3-methyl glutaryl coenzyme A (HMG-CoA) reductase and used most frequently to reduce plasma cholesterol levels and to decrease cardiovascular events. However, statins also have been reported to have undesirable side effects such as myotoxicity and hepatotoxicity associated with their intrinsic efficacy mechanisms. Clinical studies recurrently reported that statin therapy elevated the level of liver enzymes such as ALT and AST in patients suggesting possible liver toxicity due to statins. This observation has been drawn great attention since statins are the most prescribed drugs and statin-therapy was extended to a larger number of high-risk patients. Here we employed rat primary hepatocytes and microarray technique to understand underlying mechanism responsible for statin-induced liver toxicity on cell level. We isolated genes whose expressions were commonly modulated by statin treatments and examined their biological functions. It is of interest that those genes have function related to response to stress in particular immunity and defense in cells. Our study provided the basic information on cellular mechanism of statin-induced cytotoxicity and may serve for finding indicator genes of statin -induced toxicity in rat primary hepatocytes.

• 대한수의학회지
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• 제46권4호
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• pp.315-322
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• 2006

Ethanol abuse is associated with liver injury, neurotoxicity, modulation of immune responses, and increased risk for cancer, whereas moderate ethanol consumption exerts protective effects against liver injury. However, the underlying signal transduction mechanisms of insulin-like growth factors (IGFs) which play an important regulatory role in various metabolism mechanisms are not well understood. We investigated the effects of ethanol-induced p42/44 activity on IGF-I secretion, IGF-I receptor and IGFBP-1 secretion using radioimmunoassay and western blotting in primary cultured rat hepatocytes. The p42/44 activity, IGF-I secretion and IGF-I receptor activity significantly accelerated compared to control at 10 and 30 min after 200 mM ethanol treatment, but then it became suppressed at 180 min. In contrast, IGFBP-1 secretion was inhibited compared to control at 30 min after 200 mM ethanol treatment, but increased at 180 min. The IGF-I secretion, IGF-I receptor and p42/44 activity at 30 min after 200 mM ethanol treatment accelerated with increasing ethanol concentration but IGFBP-1 secretion inhibited (p<0.05). The increased IGF-I secretion, inhibited IGFBP-1 secretion and IGF-IR activity by ethanol-induced temporal p42/44 activity at 30 min after ethanol treatment was blocked by treatment with PD98059. Alcohol dehydrogenase (ADH) inhibitor, 4-methylpyramazole blocked the changes of IGF-I secretion, IGFBP-1 secretion, and IGF-IR activity by ethanol-induced p42/44 activity at 30 and 180 min. Taken together, these results suggest that ethanol is involved in the modulation of IGF-I and IGFBP-1 secretion and IGF-IR activity by p42/44 activity in primary cultured rat hepatocytes. In addition, changing of p42/44 activity by ethanol was caused with ADH.

• Investigative Magnetic Resonance Imaging
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• 제14권2호
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• pp.151-155
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• 2010

일차성 간림프종은 전체 림프절외장기를 침범하는 림프종의 1% 미만에서 나타나는 매우 드문 질환이다. 저자들은 수술로 확진된 일차성 간림프종의 자기공명영상과 병리 소견의 특징을 보고한다. 간세포 특이 조영제를 주입하여 얻은 역동적 조영증강 영상에서 점차적으로 조영증강되어 간내담관암과 유사하게 보였다. 그러나 20분 지연 후 얻은 간담관기 영상과 확산강조영상에서 서로 다른 신호강도를 보이는 세 층의 띠모양의 병변이 특징적으로 보였으며 이는 병리적으로 외층의 생존 종양, 중간층의 괴사된 종양, 및 종양에 둘러싸인 중앙부의 괴사된 간 실질과 일치되는 소견을 보였다.

• 한국간담췌외과학회지
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• 제27권4호
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• pp.342-349
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• 2023

Backgrounds/Aims: Liver organoids have emerged as a powerful tool for studying liver biology and disease and for developing new therapies and regenerative medicine approaches. For organoid culture, Matrigel, a type of extracellular matrix, is the most commonly used material. However, Matrigel cannot be used for clinical applications due to the presence of unknown proteins that can cause immune rejection, batch-to-batch variability, and angiogenesis. Methods: To obtain human primary hepatocytes (hPHs), we performed 2 steps collagenase liver perfusion protocol. We treated three small molecules cocktails (A83-01, CHIR99021, and HGF) for reprogramming the hPHs into human chemically derived hepatic progenitors (hCdHs) and used hCdHs to generate liver organoids. Results: In this study, we report the generation of liver organoids in a collagen scaffold using hCdHs. In comparison with adult liver (or primary hepatocyte)-derived organoids with collagen scaffold (hALO_C), hCdH-derived organoids in a collagen scaffold (hCdHO_C) showed a 10-fold increase in organoid generation efficiency with higher expression of liver- or liver progenitor-specific markers. Moreover, we demonstrated that hCdHO_C could differentiate into hepatic organoids (hCdHO_C_DM), indicating the potential of these organoids as a platform for drug screening. Conclusions: Overall, our study highlights the potential of hCdHO_C as a tool for liver research and presents a new approach for generating liver organoids using hCdHs with a collagen scaffold.