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Xu X, Man K, Zheng SS, Liang TB, Lee TK, Ng KT, Fan ST, Lo CM. Attenuation of acute phase shear stress by somatostatin improves small-for-size liver graft survival. Liver Transpl 2006; 12:621-7. [PMID: 16555322 DOI: 10.1002/lt.20630] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The major concern of living donor liver transplantation is small-for-size graft injury at the early phase after transplantation. Novel therapeutic strategies should be developed. To investigate the protective effect of somatostatin related to hemodynamic stress on small-for-size liver graft injury, we applied a treatment regimen of low-dose somatostatin in a rat orthotopic liver transplantation model using small-for-size grafts (median, 38.7%; range, 35-42%). Somatostatin was given at 5 minutes before total hepatectomy and immediately after reperfusion in the recipient (20 microg/kg). Graft survival, portal hemodynamics, intragraft gene expression and hepatic ultrastructural changes were compared between the rats with or without somatostatin treatment. Seven-day graft survival rates in the somatostatin treatment group were significantly improved compared to the control group (66.7% vs. 16.7%, P = 0.036). In the treatment group, portal pressure and hepatic surface blood flow were significantly decreased within the first 30 minutes after reperfusion, whereas in the control group, transient portal hypertension and excessive hepatic blood flow were observed. Intragraft expression (both messenger RNA and protein) of endothelin-1 was significantly downregulated accompanied with upregulation of heme oxygenase-1 and A20. Better preservation of liver function was found in the treatment group. Hepatic ultrastructure, especially the integrity of sinusoids, was well protected in the treatment group. In conclusion, low-dose somatostatin rescues small-for-size grafts from acute phase injury in liver transplantation by attenuation of acute-phase shear stress that resulted from transient portal hypertension.
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Affiliation(s)
- Xiao Xu
- Centre for the Study of Liver Disease and Department of Surgery, The University of Hong Kong, Pokfulam, Hong Kong, China
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Tong XK, Nicolakakis N, Kocharyan A, Hamel E. Vascular remodeling versus amyloid beta-induced oxidative stress in the cerebrovascular dysfunctions associated with Alzheimer's disease. J Neurosci 2006; 25:11165-74. [PMID: 16319316 PMCID: PMC6725645 DOI: 10.1523/jneurosci.4031-05.2005] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The roles of oxidative stress and structural alterations in the cerebrovascular dysfunctions associated with Alzheimer's disease (AD) were investigated in transgenic mice overexpressing amyloid precusor protein (APP+) or transforming growth factor-beta1 (TGF+). Age-related impairments and their in vitro reversibility were evaluated, and underlying pathogenic mechanisms were assessed and compared with those seen in AD brains. Vasoconstrictions to 5-HT and endothelin-1 were preserved, except in the oldest (18-21 months of age) TGF+ mice. Despite unaltered relaxations to sodium nitroprusside, acetylcholine (ACh) and calcitonin gene-related peptide-mediated dilatations were impaired, and there was an age-related deficit in the basal availability of nitric oxide (NO) that progressed more gradually in TGF+ mice. The expression and progression of these deficits were unrelated to the onset or extent of thioflavin-S-positive vessels. Manganese superoxide dismutase (SOD2) was upregulated in pial vessels and around brain microvessels of APP+ mice, pointing to a role of superoxide in the dysfunctions elicited by amyloidosis. In contrast, vascular wall remodeling associated with decreased levels of endothelial NO synthase and cyclooxygenase-2 and increased contents of vascular endothelial growth factor and collagen-I and -IV characterized TGF+ mice. Exogenous SOD or catalase normalized ACh dilatations and NO availability in vessels from aged APP+ mice but had no effect in those of TGF+ mice. Increased perivascular oxidative stress was not evidenced in AD brains, but vascular wall alterations compared well with those seen in TGF+ mice. We conclude that brain vessel remodeling and associated alterations in levels of vasoactive signaling molecules are key contributors to AD cerebrovascular dysfunctions.
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Affiliation(s)
- Xin-Kang Tong
- Laboratory of Cerebrovascular Research, Montreal Neurological Institute, McGill University, Montréal, Québec, H3A 2B4, Canada
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Kikkawa R, Fujikawa M, Yamamoto T, Hamada Y, Yamada H, Horii I. IN VIVO HEPATOTOXICITY STUDY OF RATS IN COMPARISON WITH IN VITRO HEPATOTOXICITY SCREENING SYSTEM. J Toxicol Sci 2006; 31:23-34. [PMID: 16538041 DOI: 10.2131/jts.31.23] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
For the establishment of a high throughput screening system using primary cell cultures, investigation of elucidated toxicities to assess the correlation between in vitro and in vivo hepatotoxicity is necessary in the safety evaluation of the compound. In the previous study, we reported the usability of rat primary cultured hepatocytes for establishment of high throughput screening system. To confirm the reliability of rat primary hepatocytes culture screening system, we conducted a single-dose in vivo study with relatively high dose of hepatotoxicant in rats using 4 reference compounds (acetaminophen, amiodarone, tetracycline, carbon tetrachloride), and investigated histopathological changes and expression of oxidative stress-related proteins by immunohistochemistry. We also carried out a proteomics analysis for estimating the reliable and sensitive biomarkers. Histopathologically, compound-specific hepatotoxicity was detected at 24 hr after administration in all compounds except amiodarone, which is known to induce phospholipidosis. Immunohistochemically, oxidative stress-related proteins were increased within 6 hr after administration in all treated groups. Proteomics analysis revealed several protein biomarkers related to oxidative stress and mitochondrial metabolism-regulation, which had been previously detected by proteomics analysis in in vitro screening system. Oxidative stress-related proteins were considered as useful biomarkers of hepatotoxicity; since they were detected by immunohistochemistry and proteomics analysis prior to appearance of compound-specific histopathological changes detected by light microscopy. Considering the relevance of in vitro system to in vivo system from the aspect of new biomarkers related to the toxicogenomics/toxicoproteomics, in vitro primary cell culture system would be sufficient to detect hepatotoxicity in the early stage of drug discovery.
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Affiliation(s)
- Rie Kikkawa
- Worldwide Safety Sciences, Pfizer Global Research and Development, Nagoya Laboratories, Pfizer Inc., 5-2 Taketoyo, Aichi 470-2393, Japan.
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Holweg CTJ, Balk AHMM, Uitterlinden AG, Niesters HGM, Maat LPWM, Weimar W, Baan CC. Functional heme oxygenase-1 promoter polymorphism in relation to heart failure and cardiac transplantation. J Heart Lung Transplant 2005; 24:493-7. [PMID: 15797755 DOI: 10.1016/j.healun.2004.02.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2003] [Revised: 02/18/2004] [Accepted: 02/20/2004] [Indexed: 11/21/2022] Open
Abstract
We investigated the functional promoter repeat polymorphism (GT)(n) in the oxidative stress-induced enzyme heme oxygenase-1 in relation to heart failure and complications after transplantation. No influence of the polymorphism on the development of heart failure, graft survival, acute rejection, or transplant atherosclerosis was found.
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Affiliation(s)
- Cecile T J Holweg
- Department of Internal Medicine, University Medical Center Rotterdam, Rotterdam, The Netherlands.
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Man K, Ng KT, Lee TK, Lo CM, Sun CK, Li XL, Zhao Y, Ho JW, Fan ST. FTY720 attenuates hepatic ischemia-reperfusion injury in normal and cirrhotic livers. Am J Transplant 2005; 5:40-9. [PMID: 15636610 DOI: 10.1111/j.1600-6143.2004.00642.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Hepatic ischemia-reperfusion injury is an inevitable consequence during liver surgery. The outcome is particularly poor in cirrhotic livers, which are more prone to hepatic ischemia-reperfusion injury. We aim to study whether FTY720 could attenuate hepatic ischemia-reperfusion injury both in normal and in cirrhotic livers. We applied a 70% liver-ischemia (60 min) model in rats with normal or cirrhotic livers. FTY720 was given 20 min before ischemia and 10 min before reperfusion (1 mg/kg, i.v.). Liver tissues and blood were sampled at 20 min, 60 min, 90 min, 6 h and 24 h after reperfusion for detection of MAPK-Egr-1, Akt pathways and caspase cascade. Hepatic ultrastructure and apoptosis were also compared. FTY720 significantly improved liver function in the rats with normal and cirrhotic livers. Akt pathway was activated at 6 and 24 h after reperfusion. FTY720 significantly down-regulated Egr-1, ET-1, iNOS and MIP-2 accompanied with up-regulation of A20, IL-10, HO-1 and Hsp70. MAPK (Raf-MEK-Erk) pathway was down-regulated. Hepatic ultrastructure was well maintained and fewer apoptotic liver cells were found in the FTY720 groups. In conclusion, FTY720 attenuates ischemia-reperfusion injury in both normal and cirrhotic livers by activation of cell survival Akt signaling and down-regulation of Egr-1 via Raf-MEK-Erk pathway.
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Affiliation(s)
- Kwan Man
- Centre for the Study of Liver Disease and Department of Surgery, The University of Hong Kong, Pokfulam, Hong Kong, China.
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Man K, Lee TK, Liang TB, Lo CM, Fung PCW, Tsui SH, Li XL, Ng KT, Fan ST. FK 409 ameliorates small-for-size liver graft injury by attenuation of portal hypertension and down-regulation of Egr-1 pathway. Ann Surg 2004; 240:159-68. [PMID: 15213632 PMCID: PMC1356388 DOI: 10.1097/01.sla.0000129673.13552.c0] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
OBJECTIVE To investigate whether low-dose nitric oxide donor FK 409 could attenuate small-for-size graft injury in liver transplantation using small-for-size grafts. SUMMARY BACKGROUND DATA The major concern of live donor liver transplantation is small-for-size graft injury at the early phase after transplantation. Novel therapeutic strategies should be investigated. METHODS We employed a rat orthotopic liver transplantation model using small-for-size (40%) graft. FK 409 was given at 30 minutes before graft harvesting (2 mg/kg) to the donor and immediately after reperfusion (1 mg/kg) to the recipient (FK group). Graft survival, intragraft genes expression, portal hemodynamics, and hepatic ultrastructural changes were compared between the 2 groups. RESULTS Seven-day graft survival rates in the FK group were significantly improved compared with those of rats not receiving FK 409 (control group; 80% versus 28.6%, P = 0.018). In the FK group, portal pressure was significantly decreased within the first 60 minutes after reperfusion whereas in the control group, transient portal hypertension was observed. Intragraft expression (both mRNA and protein) of early growth response-1, endothelin-1, endothelin-1 receptor A, tumor necrosis factor-alpha, macrophage-inflammatory protein-2, and inducible nitric oxide synthase was significantly down-regulated accompanied with up-regulation of heme oxygenase-1, A20, interferon-gamma-inducible protein-10, and interleukin-10 during the first 24 hours after reperfusion. Hepatic ultrastructure, especially the integrity of sinusoids was well protected in the FK group. CONCLUSIONS Low-dose FK 409 rescues small-for-size grafts in liver transplantation by attenuation of portal hypertension and amelioration of acute phase inflammatory response by down-regulation of Egr-1, together with prior induction of heat shock proteins.
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Affiliation(s)
- Kwan Man
- Department of Surgery, Centre for the Study of Liver Disease, University of Hong Kong Medical Centre, Queen Mary Hospital, Hong Kong, China
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Wagner KR, Dwyer BE. Hematoma Removal, Heme, and Heme Oxygenase Following Hemorrhagic Stroke. Ann N Y Acad Sci 2004; 1012:237-51. [PMID: 15105270 DOI: 10.1196/annals.1306.020] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The hemorrhagic strokes, intracerebral (ICH) and subarachnoid hemorrhage (SAH), often have poor outcomes. Indeed, the most common hemorrhagic stroke, ICH, has the highest mortality and morbidity rates of any stroke subtype. In this report, we discuss the evidence for the staging of red blood cell removal after ICH and the significance of control of this process. The protective effects of clinically relevant metalloporphyrin heme oxygenase inhibitors in experimental models of ICH and in superficial siderosis are also discussed. We also examine literature paradoxes related to both heme and heme oxygenase in various disorders of the central nervous system. Last, new data are presented that support the concept that heme, although primarily a pro-oxidant, can also have antioxidant properties.
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Affiliation(s)
- Kenneth R Wagner
- Medical Research Service, Department of Veterans Affairs Medical Center, University of Cincinnati College of Medicine, Cincinnati, Ohio 45220, USA.
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Lin HY, Juan SH, Shen SC, Hsu FL, Chen YC. Inhibition of lipopolysaccharide-induced nitric oxide production by flavonoids in RAW264.7 macrophages involves heme oxygenase-1. Biochem Pharmacol 2003; 66:1821-32. [PMID: 14563492 DOI: 10.1016/s0006-2952(03)00422-2] [Citation(s) in RCA: 163] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The role of heme oxygenase-1 (HO-1) played in the inhibitory mechanism of flavonoids in lipopolysaccharide (LPS)-induced responses remained unresolved. In the present study, flavonoids, including 3-OH flavone, baicalein, kaempferol, and quercetin, induced HO-1 gene expression at the protein and mRNA levels in the presence or absence of LPS in RAW264.7 macrophages. This effect was associated with suppression of LPS-induced nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) protein expression. Hemin induced HO-1 protein expression and this was associated with the suppression of LPS-induced NO production and iNOS protein expression in a dose-dependent manner. In addition, an increase in bilirubin production was found in flavonoid- and hemin-treated cells. Hemin, at the doses of 10, 20, and 50 microM, dose-dependently stimulated the flavonoid (50 microM)-induced HO-1 protein expression, and enhanced their inhibitory effects on LPS-induced NO production and iNOS protein expression. Pretreatment of the HO-1 inhibitor, tin protoporphyrin (10 microM), attenuated the inhibitory activities of the indicated flavonoids on LPS-induced NO production. Morphologic analysis showed that 3-OH flavone, baicalein, kaempferol, quercetin, hemin, and tin protoporphyrin did not cause any change in cell viability in the presence or absence of LPS. In contrast, only 3-OH flavone showed a significant inhibition of cell growth using the MTT assay. Transfection of an HO-1 vector in macrophages (HO-1/RAW264.7) resulted in a 3-fold increase in HO-1 protein compared with that the parental RAW264.7 cells. NO production mediated by LPS in HO-1 over-expressed RAW264.7 cells (HO-1/RAW264.7) was significant less than that in parental RAW264.7 cells. 3-OH Flavone, baicalein, kaempferol, and quercetin showed a more significant inhibition on LPS-induced NO production in HO-1/RAW264.7 cells than in parental RAW264.7 cells. These results provide evidence on the role of HO-1 in the inhibition of LPS-induced NO production by flavonoids. A combination of HO-1 inducers (i.e. hemin) and flavonoids might be an effective strategy for the suppression of LPS-induced NO production.
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Affiliation(s)
- Hui-Yi Lin
- Graduate Institute of Pharmaceutical Sciences, School of Pharmacy, Taipei Medical University, Taipei, Taiwan ROC
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Man K, Lo CM, Lee TKW, Li XL, Ng IOL, Fan ST. Intragraft gene expression profiles by cDNA microarray in small-for-size liver grafts. Liver Transpl 2003; 9:425-32. [PMID: 12682897 DOI: 10.1053/jlts.2003.50066] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The aim of this study is to identify the molecular mechanism of small-for-size graft injury through large-scale expression measurement of intragraft gene profile by carrier DNA (cDNA) microarray screening in liver transplantation. The studies compared 1,081 intragraft genes expression profiles using cDNA microarray of small-for-size grafts (<30% of recipient liver weight) with those of whole grafts (control group) 1, 3, and 24 hours after reperfusion in a rat liver transplantation model. Intragraft gene expression was detected by quantitative reverse-transcriptase polymerase chain reaction (RT-PCR). Hepatic ultrastructural features were shown by electron microscopy. In the small-for-size grafts, by cDNA microarray study, the vasoconstriction genes were found up-regulated together with adhesion molecules at 1 hour after reperfusion. Three and 24 hours after reperfusion, the vasopressin genes were found up-regulated together with adhesion molecules, inflammatory mediators and cell death signals, accompanied with down-regulation of the genes related to energy metabolism. By quantitative RT-PCR, intragraft messenger RNA (mRNA) expression of endothelin-1 (ET-1) and endothelin-1 receptor A (ETA) was up-regulated during the first 24 hours after reperfusion accompanied with down-regulation of heme oxygenase-1 (HO-1). The intragraft mRNA and plasma levels of inflammatory cytokines (interleukin [IL]-6, IL-15, tumor necrosis factor [TNF]-alpha) also were overexpressed during the first 24 hours after reperfusion. Sinusoidal congestion and disruption were found accompanied with mitochondrial swelling during the first 24 hours after reperfusion. The up-regulation of intragraft vasoconstriction genes accompanied by early overexpression of adhesion molecules and apoptotic signals, as well as down-regulation of HO-1 in small-for-size grafts may be related to sinusoidal injury leading to graft damage in liver transplantation.
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Affiliation(s)
- Kwan Man
- Centre for the Study of Liver Disease, The University of Hong Kong Medical Centre, Queen Mary Hospital, China
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Liang TB, Man K, Kin-Wah Lee T, Hong-Teng Tsui S, Lo CM, Xu X, Zheng SS, Fan ST, Wong J. Distinct intragraft response pattern in relation to graft size in liver transplantation. Transplantation 2003; 75:673-8. [PMID: 12640308 DOI: 10.1097/01.tp.0000048490.24429.89] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND The molecular mechanism of small-for-size graft injury remains unclear. The aim of this study is to investigate the gene expression pattern of acute phase response in relation to graft size in a rat-liver transplantation model. METHODS A rat orthotopic liver transplantation model using 30%, 50%, and whole grafts was used. The graft survival rates and liver morphology were compared among the three groups. Two transcription factors, nuclear factor (NF)-kappaB (p65) and early growth response (Egr-1), and their downstream genes were compared. RESULTS According to the graft size, the rats were grouped as follows: group 1 (n=20), 32% (24-47%); group 2 (n=10), 56% (50-65%); and group 3 (n=10), 104% (89-120%). The 7-day survival rates were 20% (P=0.039 vs. group 2, P=0.000 vs. group 3), 60%, and 100% in groups 1, 2, and 3, respectively. Dilation of hepatic sinusoids and vacuolization of hepatocytes were observed in group 1. Up-regulation of Egr-1 and endothelin (ET)-1 and over-expression of nitric oxide synthase (iNOS) was found in group 1, but heme oxygenase (HO)-1 and A20 were down-regulated. At 24 hours after reperfusion, the intragraft protein level of heat-shock protein (Hsp)-70 was significantly lower in group 1 than that in group 3 (12.4 vs. 17.0 ng/mL, P=0.04). More apoptotic nuclei were found in group 1. CONCLUSIONS Small-for-size graft injury was related to early over-expression of Egr-1 associated with up-regulation of ET-1 and deterioration of intracellular homeostasis reflected by down-regulation of Hsps and A20.
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Affiliation(s)
- Ting-Bo Liang
- Centre for the Study of Liver Disease, The University of Hong Kong Medical Centre, Queen Mary Hospital, Hong Kong SAR, China
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Man K, Fan ST, Lo CM, Liu CL, Fung PCW, Liang TB, Lee TKW, Tsui SHT, Ng IOL, Zhang ZW, Wong J. Graft injury in relation to graft size in right lobe live donor liver transplantation: a study of hepatic sinusoidal injury in correlation with portal hemodynamics and intragraft gene expression. Ann Surg 2003; 237:256-64. [PMID: 12560784 PMCID: PMC1522144 DOI: 10.1097/01.sla.0000048976.11824.67] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE To investigate the degree and mechanism of hepatic sinusoidal injury in different graft sizes in right lobe live donor liver transplantation (LDLT). SUMMARY BACKGROUND DATA Liver grafts from living donors are likely to be small-for-size for adult recipients. Graft injury after reperfusion is common, but the mechanism and degree of injury remain unclear. The hepatic sinusoidal injury in different graft sizes and its relationship with portal hemodynamics and intragraft gene response at the early phase after reperfusion have not been studied in right lobe LDLT. METHODS From May 2000 to November 2001, 40 adults receiving right lobe LDLT had portal pressure measured continuously before and after reperfusion. Liver biopsies were taken before and after reperfusion for detection of vasoregulatory genes (endothelin-1 and endothelial nitric oxide synthase) and heat shock genes (heat shock protein 70 and heme oxygenase-1), and electron microscope examination. Blood samples from the portal vein and suprahepatic inferior vena cava were taken for the measurement of plasma nitric oxide level. RESULTS The recipients were grouped according to the ratio of graft weight to estimated standard liver weight: group 1 (n = 10), less than 40%; group 2 (n = 21), 40% to 60%; and group 3 (n = 9), more than 60%. The portal pressures recorded after reperfusion in group 1 were significantly higher within 30 minutes of reperfusion than those in groups 2 and 3. After reperfusion, the intragraft endothelin-1 mRNA level in group 1 increased by 161% of the basal level but decreased by 31.5% and 62% of the basal level in groups 2 and 3, respectively. The intragraft mRNA level of heme oxygenase-1 in groups 1 and 2 decreased by 75.5% and 25.3% of the basal level respectively but increased by 41% of basal level in group 3. The intragraft protein level of heat shock protein 70 decreased by 50 ng/mL after reperfusion in group 1 but increased by 12.4 ng/mL and 0.6 ng/mL in groups 2 and 3, respectively. The portal vein plasma nitric oxide level decreased more significantly after reperfusion in group 1 than in group 2. Electron microscope examination of liver biopsies in group 1 showed tremendous mitochondrial swelling as well as irregular large gaps between the sinusoidal lining cells. There were two hospital deaths in group 1 and none in the other two groups. CONCLUSIONS Patients implanted with grafts less than 40% of standard liver weight suffered from transient portal hypertension early after reperfusion. The phenomenon was accompanied by intragraft upregulation of endothelin-1 and ultrastructural evidence of sinusoidal damage. The transient portal hypertension after reperfusion, subsequent endothelin-1 overexpression, and plasma nitric oxide level reduction, together with downregulation of heme oxygenase-1 and heat shock protein 70, may account for the small-for-size graft injury.
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Affiliation(s)
- Kwan Man
- Centre for the Study of Liver Disease and Department of Surgery, University of Hong Kong Medical Centre, Queen Mary Hospital, Hong Kong SAR, China
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Kaneda H, Ohno M, Taguchi J, Togo M, Hashimoto H, Ogasawara K, Aizawa T, Ishizaka N, Nagai R. Heme oxygenase-1 gene promoter polymorphism is associated with coronary artery disease in Japanese patients with coronary risk factors. Arterioscler Thromb Vasc Biol 2002; 22:1680-5. [PMID: 12377749 DOI: 10.1161/01.atv.0000033515.96747.6f] [Citation(s) in RCA: 132] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Heme oxygenase (HO) is important in the defense against oxidative stress and as a factor in an antiatherogenic mechanism. Compared with long (GT)(n) repeats, short (GT)(n) repeats in the human HO-1 gene promoter were shown to have higher transcriptional activity in response to oxidative stress. There is a strong link between oxidative stress and the pathogenesis of coronary artery disease (CAD). METHODS AND RESULTS We screened the allelic frequencies of (GT)(n) repeats in the HO-1 gene promoter in 577 patients who underwent coronary angiography. Because the distribution of numbers of (GT)(n) repeats was bimodal, we divided the alleles into 2 subclasses: class S included shorter (<27) repeats, and class L included longer (> or =27) repeats. Multivariate logistic regression models including standard coronary risk factors revealed that the genotypes were significantly related to CAD status in hypercholesterolemic, diabetic patients or in smokers. In this study, the patients with shorter GT repeats were less likely to have CAD. CONCLUSIONS Length polymorphism in the HO-1 gene promoter is related to CAD susceptibility in Japanese people who also have coronary risk factors such as hypercholesterolemia, diabetes, and smoking. HO-1 may play an antiatherogenic role in Japanese patients with these coronary risk factors.
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Affiliation(s)
- Hideaki Kaneda
- Department of Cardiovascular Medicine, The University of Tokyo, Graduate School of Medicine, Tokyo, Japan
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Dumont AS, Chow M, Kassell NF. Vasospasm. J Neurosurg 2002; 96:985-6; discussion 986-7. [PMID: 12066931 DOI: 10.3171/jns.2002.96.6.0985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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