经肝动脉灌注莪术油微球对大鼠移植性肝癌的治疗作用

目的 观察莪术油微球经肝动脉灌注对大鼠移植性肝癌的治疗作用。方法 复制１００只大鼠移植性肝癌模型,随机分为对照组,莪术油组,空白微球组,高剂量和低剂量莪术油微球组,每组２０只,经胃十二指肠动脉至肝固有动脉分别灌注生理盐水０．２－０．３ｍｌ,莪术油１０ｍｇ／ｋｇ,空白微球１０ｍｇ／ｋｇ及高低剂量莪术油微球１０ｍｇ／ｋｇ和５ｍｇ／ｋｇ。     

Enhanced antitumor efficacy on hepatoma-bearing rats with adriamycin-loaded nanoparticles administered into hepatic artery

AIM: To investigate the antitumor activity of adriamycin (ADR) encapsulated in nanoparticles (NADR) and injected into the hepatic artery of hepatoma-bearing rats. METHODS: NADR was prepared by the interfacial polymerization method. Walker-256 carcinosarcomas were surgically implanted into the left liver lobes of 60 male Wistar rats, which were divided into 4 groups at random (15 rats per group). On the 7th day after implantation, normal saline (NS), free ADR (FADR), NADR, or ADR mixed with unloaded nanoparticles (ADR+NP) was respectively injected via the hepatic artery (i.a.) of rats in different groups. The dose of ADR in each formulation was 2.0 mg/kg body weight and the concentration was 1.0 mg/mL. Survival time, tumor enlargement ratio, and tumor necrosis degree were compared between each group. RESULTS: Compared with the rats that received NS i.a., the rats that received FADR or ADR+NP acquired apparent inhibition on tumor growth, as well as prolonged their life span. Further significant anticancer efficacy was observed in rats that received i.a. administration of NADR. Statistics indicated that NADR brought on a more significant tumor inhibition and more extensive tumor necrosis, as compared to FADR or ADR+NP. The mean tumor enlargement ratio on the 7th day after NADR i.a. was 1.106. The mean tumor-bearing survival time was 39.50 days. Prolonged life span ratio was 109.22% as compared with rats that accepted NS. CONCLUSION: Therapeutic effect of ADR on liver malignancy can be significantly enhanced by its nanopaticle formulation and administration via hepatic artery.     

Anti-tumor activities and apoptosis-regulated mechanisms of bufalin on the orthotopic transplantation tumor model of human hepatocellular carcinoma in nude mice

AIM： To investigate anti-tumor activities and apoptosisregulated mechanisms of bufalin in the orthotopic transplantation tumor model of human hepatocellular carcinoma in nude mice.
METHODS： BEL-7402 cells of human hepatocellular carcinoma were inoculated to form subcutaneous tumors, and were implanted into the liver to establish orthotopic transplantation tumor models of human hepatocellular carcinoma in nude mice. Seventy-five animals were randomized divided into five groups （n = 15）. Bufalin was injected intraperitoneally into three groups at doses of 1.5 mg/kg （BF1）, 1 mg/kg （BF2） and 0.5 mg/kg （BF3） for d 15-24, respectively. The NS group was injected an equal volume of saline as above and adriamycin was injected intraperitoneally into the ADM group at a dose of 8.0 mg/kg for d 15. Ten mice in each group were killed at d 25 and the survival time in each group was calculated. We also observed the morphologic alterations in the myocardium, brain, liver, kidney and tumor tissues by pathology and electron microscopy, measured the apoptotic rate by TUNEL staining method, and detected the expression of apoptosis-regulated genes bcl-2 and bax by immunohistochemical staining and RT-PCR in tumor tissues.
RESULTS： The tumor volumes in each group of bufalin were reduced significantly （35.21±12.51 vs 170.39 ± 25.29; 49.83 ± 11.46 vs 170.39 ± 25.29; 83.99 ± 24.63 vs 170.39 ± 25.29, P 〈 0.01, respectively）, and the survival times were prolonged in group BF1-2 （31.8 ± 4.2 vs 23.4 ± 2.1 and 29.4 ± 3.4 vs 23.4 ± 2.1, P 〈 0.05, respectively）, and necrosis was mainly in severe or moderate degree in group BF1-2. No morphological changes were detected in the myocardium, brain, liver and kidney tissues. Apoptotic characteristics could be seen in group BF1-2. The positive rates of bcl-2 and bax protein expression of each group by immunohistochemical staining were 10.0%, 10.0%, 20.0%, 10.0% and 20.0%; 90.0%, 80.0%, 80.0%, 40.0% and 30.0%, respectively. Loss of expression of bcl-2 mRNA     

Antitumor efficacy of lidamycin on hepatoma and active moiety of its molecule

AIM: To study the in vitro and in vivo antitumor effect of lidamycin (LDM) on hepatoma and the active moiety of its molecule. METHODS: MTT assay was used to determine the growth inhibition of human hepatoma BEL-7402 cells, SMMC-7721 cells and mouse hepatoma H22 cells. The in vivo therapeutic effects of lidamycin and mitomycin C were determined by transplantable hepatoma 22 (H22) in mice and human hepatoma BEL-7402 xenografts in athymic mice. RESULTS: In terms of IC50 values, the cytotoxicity of LDM was 10 000-fold more potent than that of mitomycin C (MMC) and adriamycin (ADM) in human hepatoma BEL-7402 cells and SMMC-7721 cells. LDM molecule consists of two moieties, an aproprotein (LDP) and an enediyne chromophore (LDC). In terms of IC50 values, the potency of LDC was similar to LDM. However, LDP was 105-fold less potent than LDM and LDC to hepatoma cells. For mouse hepatoma H22 cells, the IC50 value of LDM was 0.025 nmol/L. Given by single intravenous injection at doses of 0.1, 0.05 and 0.025 mg/kg, LDM markedly suppressed the growth of hepatoma 22 in mice by 84.7%, 71.6% and 61.8%, respectively. The therapeutic indexes (TI) of LDM and MMC were 15 and 2.5, respectively. By 2 iv. injections in two experiments, the growth inhibition rates by LDM at doses of 0.1, 0.05, 0.025, 0.00625 and 0.0125 mg/kg were 88.8-89.5%, 81.1-82.5%, 71.2-74.9%, 52.3-59.575%, and 33.3-48.3%, respectively. In comparison, MMC at doses of 5, 2.5, and 1.25 mg/kg inhibited tumor growth by 69.7-73.6%, 54.0-56.5%, and 31.5-52.2%, respectively. Moreover, in human hepatoma BEL-7402 xenografts, the growth inhibition rates by LDM at doses of 0.05 mg/kg ×2 and 0.025 mg/kg ×2 were 68.7% and 27.2%, respectively. However, MMC at the dose of 1.25 mg/kg ×2 showed an inhibition rate of 34.5%. The inhibition rate of tumor growth by LDM was higher than that by MMC at the tolerated dose. CONCLUSION: Both LDM and its chromophore LDC display extremely potent cytotoxicity to hepatoma cells. LDM shows a remarkable therapeutic efficacy against murine and human hepatomas in vivo.     

Inhibitory effects of saikosaponin-d on CCl4-induced hepatic fibrogenesis in rats

AIM： To investigate the suppressive effect of saikosaponin-d （SSd） on hepatic fibrosis in rats induced by CCh injections in combination with alcohol and high fat, low protein feeding and its relationship with the expression of nuclear factor-κB （NF-κB）, tumor necrosis factor-alpha （TNF-α） and interleukins-6 （IL-6）. METHODS： Hepatic fibrosis models were induced by subcutaneous injection of CCh at a dosage of 3 mL/kg in rats. At the same time, rats in treatment groups were injected intraperitoneally with SSd at different doses （1.0, 1.5 and 2.0 mg/kg） once daily for 6 wk in combination with CCh, while the control group received olive oil instead of CCh. At the end of the experiment, rats were anesthetized and killed （except for 8 rats which died during the experiment; 2 from the model group, 3 in high-dose group, 1 in medium-dose group and 2 in lowdose group）. Hernatoxylin and eosin （HE） staining and Van Gieson staining were used to examine the changes in liver pathology. The levels of alanine aminotransferase （ALT）, triglyeride （TG）, albumin （ALB）, globulin （GLB）, hyaluronic acid （HA） and larninin （LN） in serum and the content of hydroxyproline （HYP） in liver were measured by biochemical examinations and radioimmuneoassay, respectively. In addition, the expression of TNF-α and IL-6 in liver homogenate was evaluated by enzymelinked immunosorbent assay （ELISA） and the levels of NF-κBp65 and I-κBa in liver tissue were analyzed by Western blotting. RESULTS： Both histological examination and Van Gieson staining demonstrated that SSd could attenuate the area and extent of necrosis and reduce the scores of liver fibrosis. Similarly, the levels of ALT, TG, GLB, HA, and LN in serum, and the contents of HYP, TNF-α and IL-6 in liver were all significantly increased in model group in comparison with those in control group. Whereas, the treatment with SScl markedly reduced all the above parameters compared with the model group, especially in the medium gr     

Prostacyclin inhibition by indomethacin aggravates hepatic damage and encephalopathy in rats with thioacetamide-induced fulminant hepatic failure

AIM: Vasodilatation and increased capillary permeability have been proposed to be involved in the pathogenesis of acute and chronic form of hepatic encephalopathy. Prostacyclin (PGI2) and nitric oxide (NO) are important contributors to hyperdynamic circulation in portal hypertensive states. Our previous study showed that chronic inhibition of NO had detrimental effects on the severity of encephalopathy in thioacetamide (TAA)-treated rats due to aggravation of liver damage. To date, there are no detailed data concerning the effects of PGI2 inhibition on the severity of hepatic encephalopathy during fulminant hepatic failure. METHODS: Male Sprague-Dawley rats weighing 300-350 g were used. Fulminant hepatic failure was induced by intraperitoneal injection of TAA (350 mg/(kg·d) for 3 d. Rats were divided into two groups to receive intraperitoneal injection of indomethacin (5 mg/(kg·d), n = 20) or normal saline (N/S, n = 20) for 5 d, starting 2 d before TAA administration. Severity of encephalopathy was assessed by the counts of motor activity measured with Opto-Varimex animal activity meter. Plasma tumor necrosis factor-α (TNF-α, an index of liver injury) and 6-keto-PGF1α (a metabolite of PGI2) levels were measured by enzyme-linked immunosorbent assay. RESULTS: As compared with N/S-treated rats, the mortality rate was significantly higher in rats receiving indomethacin (20% vs5%, P<0.01). Inhibition of PGI2 created detrimental effects on total movement counts (indomethacin vs N/S: 438±102 vs 841±145 counts/30 min, P<0.05). Rats treated with indomethacin had significant higher plasma levels of TNPa (indomethacin vs N/S: 22±5 vs 10±1 pg/mL, P<0.05) and lower plasma levels of 6-keto-PGF1α (P<0.001), but not total bilirubin or creatinine (P>0.05), as compared with rats treated with N/S. CONCLUSION: Chronic indomethacin administration has detrimental effects on the severity of encephalopathy in TAA-treated rats and this phenomenon may be attributed to the aggravation of liver injury. This study suggests that PGI2 may provide a protective role in the development of fulminant hepatic failure.     

Effect of insulin-sensitizing agents in combination with ezetimibe, and valsartan in rats with non-alcoholic fatty liver disease

AIM: To assess whether treatment with insulin-sensitizing agents (ISAs) in combination with ezetimibe and valsartan have greater effect on hepatic fat content and lipid peroxidation compared to monotherapy in the methionine choline-deficient diet (MCDD) rat model of non-alcoholic fatty liver disease (NAFLD). METHODS: Rats (n = 6 per group) were treated with different drugs, including MCDD only, MCDD diet with either metformin (200 mg/kg), rosiglitazone (3 mg/kg), metformin plus rosiglitazone (M R), ezetimibe (2 mg/ kg), valsartan (2 mg/kg), or combination of all drugs for a total of 15 wk. Liver histology, lipids, parameters of oxidative stress and TNF-alpha were measured. RESULTS: Fatty liver (FL) rats demonstrated severe hepatic fatty infiltration (> 91% fat), with an increase in hepatic TG ( 1263%, P < 0.001), hepatic cholesterol ( 245%, P < 0.03), hepatic MDA levels ( 225%, P < 0.001), serum TNF-alpha (17.8±10 vs 7.8±0.0, P < 0.001), but a decrease in hepatic alpha tocopherol (-74%, P < 0.001) as compared to the control rats. Combination therapy with all drugs produced a significant decrease in liver steatosis (-54%), hepatic TG (-64%), hepatic cholesterol (-31%) and hepatic MDA (-70%), but increased hepatic alpha tocopherol ( 443%) as compared to FL rats. Combination therapy with ISA alone produced a smaller decrease in liver steatosis (-32% vs -54%, P < 0.001) and in hepatic MDA levels (-55% vs -70%, P < 0.01), but a similar decrease in hepatic lipids when compared with the all drugs combination. TNF-alpha levels decreased significantly in all treatment groups except in ISA group. CONCLUSION: Combination therapies have a greater effect on liver fat content as compared to monotherapy. Rosiglitazone appears to improve hepatic steatosis to a greater extent than metformin.     

Inhibitory effect of Huangqi Zhechong decoction on liver fibrosis in rat

AIM: To assess the inhibitory effect of Huangqi Zhechong decoction on hepatic fibrosis in rats induced by CCl(4) plus alcohol and high fat low protein diet. METHODS: Male SD rats were randomly divided into hepatic fibrosis model group, control group and 3 treatment groups consisting of 12 rats in each group. Except for the normal control group, all the rats were subcutaneously injected with CCl(4) at a dosage of 3 mL/kg. In 3 treated groups, either high-dose group (9 mL/kg), or medium-dose group (6 mL/kg), or low-dose group (3 mL/kg) was daily gavaged with Huangqi Zhechong decoction, and saline vehicle was given to model and normal control rats. Enzyme-linked immunosorbent assay (ELISA) and biochemical examinations were used to determine the changes of alanine aminotransferase (ALT), aspartate aminotransferase (AST), hyaluronic acid (HA), laminin (LN), type-III-procollagen-N-peptide (PIIIP), and type IV collagen content in serum, and hydroxyproline (Hyp) content in liver after sacrificing the rats. Pathologic changes, particularly fibrosis were examined by hematoxylin and eosin (HE) and Van Gieson staining. RESULTS: Compared with the model control group, serum ALT, AST, HA, LN, PIIIP and type IV collagen levels dropped markedly in Huangqi Zhechong decoction groups, especially in the medium-dose Huangqi Zhechong decoction group (1 954+/-576 U/L vs 759+/-380 U/L, 2 735+/-786 U/L vs 1 259+/-829 U/L, 42.74+/-7.04 ng/mL vs 20.68+/-5.85 ng/mL, 31.62+/-5.84 ng/mL vs 14.87+/-1.45 ng/mL, 3.26+/-0.69 ng/mL vs 1.47+/-0.46 ng/mL, 77.68+/-20.23 ng/mL vs 25.64+/-4.68 ng/mL, respectively) (P<0.05). The Hyp content in liver tissue was also markedly decreased (26.47+/-11.24 mg/mgprot vs 9.89+/-3.74 mg/mgprot) (P<0.01). Moreover, the stage of the rat liver fibrosis in Huangqi Zhechong decoction groups was lower than that in model group, and more dramatic drop was observed in medium-dose Huangqi Zhechong decoction group (P<0.01). CONCLUSION: Huangqi Zhechong decoction can inhibit hepatic fibrosis resulted from chronic liver injure, retard the development of cirrhosis, and notably ameliorate the liver function. It may be a safe and effective therapeutic drug for patients with fibrosis.     

Endotoxin treatment causes an upregulation of the endothelin system in the liver: amelioration of increased portal resistance by endothelin receptor antagonism

BACKGROUND: Mechanisms underlying hepatic microcirculatory failure during endotoxemia are incompletely understood. Because endothelin-1 (ET-1) has been implicated in endotoxin-induced liver injury, we investigated the hepatic ET-1 system in endotoxin-treated rats. METHODS: Rats were treated with endotoxin (Escherichia coli lipopolysaccharide; 3 mg/kg, i.p.), and various determinations were made 24 h later. RESULTS: Endotoxin treatment caused 11.2 +/- 1.6% weight loss, a decrease in mean arterial pressure (MAP; 96 +/- 5 mmHg vs 108 +/- 3 mmHg; P < 0.05) and an increase in portal pressure (11.6 +/- 1.3 mmHg vs 7.4 +/- 1 mmHg; P < 0.02). No significant changes in the serum levels of liver enzymes or hepatocellular necrosis were observed. Endotoxin caused increases in hepatic ET-1 (from 345 +/- 31 to 565 +/- 38 pg/g; P < 0.01), ET-1 receptor density (from 179 +/- 16 to 340 +/- 26 fmol/mg; P < 0.02), and mRNA expression of preproendothelin-1, and ET(A) and ET(B) receptors. While the serum nitric oxide (nitrite +/- nitrate) concentration was increased in endotoxin-treated rats, that of ET-1 remained unchanged. A mixed ET(A)/ET(B) receptor antagonist, TAK-044 (10 mg/kg, i.v.), reduced the weight loss from 11.2 +/- 1.6% to 5.9 +/- 2.9% (P < 0.05) and the portal pressure from 11.6 +/- 1.3 mmHg to 8.6 +/- 0.7 mmHg (P < 0.05) in endotoxin-treated rats. The mixed ET(A)/ET(B) receptor antagonist also caused an increase in serum ET-1 concentration, but did not affect serum nitric oxide and MAP in endotoxin-treated rats. CONCLUSIONS: These results suggest that the upregulated hepatic ET-1 system is an important mechanism of increased portal resistance and related complications of endotoxemia.     

Protection of Veratrum nigrum L. var. ussuriense Nakai alkaloids against ischemia-reperfusion injury of the rat liver

AIM： TO investigate the protective effects and possible mechanisms of Veratrum nigrum L. var. ussuriense Nakai alkaloids （VnA） on hepatic ischemia/reperfusion （I/R） injury in rats.
METHODS： Forty male Wistar rats were randomly divided into four experimental groups （n = 10 in each）： （A） Control group （the sham operation group）; （8） I/R group （pretreated with normal saline）; （C） Small-dose （10 μg/kg） VnA pretreatment group; （D） Large-dose （20 μg/kg） VnA pretreatment group. Hepatic ischemia/ reperfusion （Hepatic I/R） was induced by occlusion of the portal vein and the hepatic artery for 90 min, followed by reperfusion for 240 min. The pretreatment groups were administered with VnA intraperitoneally, 30 min before surgery, while the control group and I/R group were given equal volumes of normal saline. Superoxide dismutase （SOD） activity, myeloperoxidase （MPO） activity and nitric oxide （NO） content in the liver tissue at the end of reperfusion were determined and liver function was measured. The expression of intercellular adhesion molecule-1 （ICAM-1） and E-selectin （ES） were detected by immunohistochemical examinations and Western blot analyses.
RESULTS： The results showed that hepatic I/R elicited a significant increase in the plasma levels of alanine aminotransferase （ALT： 74.53 ± 2.58 IU/L vs 1512.54 ± 200.76 IU/L, P 〈 0.01） and lactic dehydrogenase （LDH： 473.48 ± 52.17 IU/L vs 5821.53 ± 163.69 IU/L, P 〈 0.01）, as well as the levels of MPO （1.97 ± 0.11 U/g vs 2.57 ± 0.13 U/g, P 〈 0.01） and NO （69.37 ± 1.52 μmol/g protein vs 78.39 ± 2.28 μmol/g protein, P 〈 0.01） in the liver tissue, all of which were reduced by pretreatment with VnA, respectively （ALT： 1512.54 ± 200.76 IU/L vs 977.93 ± 89.62 IU/L, 909.81 ± 132.76 IU/L, P 〈 0.01, P 〈 0.01; LDH： 5821.53 ± 163.69 IU/L vs 3015.44 ± 253.01 IU/L, 2448.75 ± 169.4 IU/L, P 〈 0.01, P 〈 0.01; MPO： 2.57 ± 0.13 U/g vs 2.13 ± 0.13 U/g,     

Effect of hydroxyapatite nanoparticles on the growth and p53/c-Myc protein expression of implanted hepatic VX2 tumor in rabbits by intravenous injection

AIM: To evaluate the effect of hydroxyapatite nano-particles (Nano HAP) by intravenous injection on the inhibition of implanted hepatic VX2 tumor growth in rabbits and cell p53/c-Myc protein expression. METHODS: 60 hepatic VX2 tumor-bearing rabbits was randomly divided into five groups. Nano HAP collosol 20 mg/kg,40 mg/kg,5-FU solutions 20 mg/mL,mixed liquor of 5-FU solution 20 mg/mL and Nano HAP collosol 20 mg/kg were infused by vein,normal saline conducted as the control. The general state,weight,liver function and gross tumor volume were detected dynamically. The expression of p53 and c-Myc gene protein in tumor tissue was detected by immunohistochemistry methods. RESULTS: The growth of implanted hepatic VX2 tumors was significantly inhibited in all therapy groups,3 wk after the injection,the tumor control rates in Nano HAP collosol groups were 25.5% and 32.5% respectively,and the gross tumor volumes were obviously less than that of control group. (24.81±5.17 and 22.73±4.23 vs 33.32±5.26,P < 0.05). The tumor control rate of 5-FU group was 43.7% (18.74±4.40 vs 33.32±5.26,P < 0.05),but the general state of the animals after injection aggravated; and the adverse reaction in the drug combination group obviously decreased. Due to the effect of Nano HAP,the positive expression of tumor associated the mutated p53 and c-Myc in tumor tissue was decreased obviously compared with the control group. CONCLUSION: Nano HAP has evident inhibitory action on rabbit implanted hepatic VX2 tumor in vivo,which may be the result of decreasing the expression of the mutated p53 and c-myc,and drug combination can obviously decrease the adverse reaction of 5-FU.     

Risedronate prevents the loss of microarchitecture in glucocorticoid-induced osteoporosis in rats

Osteoporosis is a severe complication of glucocorticoid treatment. Bisphosphonates are a powerful therapeutic option to prevent osteoporotic fractures. The aims of this study were: a) to determine bone alterations induced by therapy with glucocorticoids (GC); b) to establish the efficacy of risedronate (Ris) in the prevention of these effects. We studied 40 female Sprague-Dawley rats randomly divided into 4 groups of treatment, administered 3 times a week sc: 1. Control: vehicle of methylprednisolone (GC) + vehicle of Ris; 2. Ris: Ris 5 mug/kg body weight vehicle of GC; 3. GC: GC 7 mg/kg + vehicle of Ris; 4. GC+Ris: GC 7 mg/kg, Ris 5 microg/kg. Animals were treated for 30 days and then were sacrificed. Densitometry was performed at baseline and at the end of the treatment. Right tibiae were removed for histomorphometric analyses. The GC group showed a 7% decrease in bone density vs controls (p<0.05), while the GC+Ris group was associated with a 3.5% increase in bone density vs controls (p<0.05). In the GC group, histomorphometric evaluations showed reduced bone volume (BV/TV) and thinning of trabeculae (Tb.Th) vs controls (BV/TV: 31+/-1 vs 35+/-1%, p<0.05; Tb.Th: 43+/-2 vs 50+/-3 microm, p<0.01; Ac.f: 1.8+/-0.2 vs 1.6+/-0.3 N/yr). The GC+Ris group had increased BV/TV and Tb.Th, and reduced Ac.f vs the GC group. Ris also maintained trabecular microarchitecture. At the histological level, glucocorticoid-induced osteoporosis was characterized by decreased bone volume, reduced osteoblastic activity, and deterioration of microarchitecture. Ris counteracted these effects both by prolonging osteoblast activity, and by maintaining bone microarchitecture.     

Heme oxygenase-1 induction by hemin protects liver cells from ischemia/reperfusion injury in cirrhotic rats

AIM： To investigate the potential protective effect of HO-1 on cirrhotic liver cells in rats.
METHODS： Male Wistar rats included in the current study were randomly divided into 5 groups as follows： normal （N） group; liver cirrhotic （LC） group; sham （S） group; I/R group and I/R ＋ hemin group. The model for inducing liver cirrhosis in rats was established according to a previously published protocol. Following this the segmental hepatic ischemia reperfusion operation was carried out. The rats were treated with 30 l~mol/kg hemin （HO-1 inducer, ferric portoporphyrin IX chloride） i.p. or 0.9% NaCI （control） 24 h and 12 h before hepatic ischemia for 30 min or sham laparotomy. Blood was collected for serum enzymatic measurement 6 and 12 h after reperfusion or sham laparotomy. HO-1, NF-κB and caspase-3 expressions were assessed by immunohistochemical analysis.
RESULTS： The expressions of proteins are inversely correlated to the gray values. HO-1 expression in the I/R ＋ hemin group was increased significantly than I/R group at 6 h and 12 h after hepatic I/R （6 h： 112.0± 8.3 vs 125.1± 5.7, P 〈 0.01; 12 h： 120.8± 11.0 vs 132.4 ± 6.2, P 〈 0.01）. Hemin improved serum manganese superoxide dismutase （MnSOD） （6 h： 131.3 ± 17.6 vs 107.0 ± 13.9, P 〈 0.01; 12 h： 141.4 ：E 12.5 vs 118.3± 10.2, P 〈 0.01）, lessened liver cell injury, decreased caspase-3（6 h： 166.7 ± 8.1 vs 145.5 ± 14.6, P 〈 0.01; 12 h： 172.8± 3.8 vs 148.0 ±6.5, P 〈 0.01） and NF-κB expression （6 h： 150.2 ± 8.6 vs 139.7 ±6.0, P 〈 0.01; 12 h： 151.1 ± 5.9 vs 148.1± 5.3, P 〉 0.05） and serum alanine aminotransferase （ALT） （6 h： 413.3± 104.1 vs 626.8 ±208.2, P 〈 0.01; 12 h： 322.2 ± 98.8 vs 425.8 ± 115.4, P 〈 0.05）, aspartate aminotransferase （AST） （6 h： 665.2 ± 70.1 vs 864.3± 70.4, P 〈 0.01; 12 h： 531.1 ± 98.6 vs 664.4± 115.6, P 〈 0.01）, malondialdehyde （MDA） levels （6 h： 11.1 ± 2.17 vs 13.5 ±2.01, P 〈 0.01; 12 h： 9.36     

Effects of tumor necrosis factor, endothelin and nitric oxide on hyperdynamic circulation of rats with acute and chronic portal hypertension

AIM:To evaluate the effect of tumor necrosis factor (TNF),endothelin (ET) and nitric oxide (NO) on hyperdynamic circulation (HC) of rats with acute and chronic portal hypertension (PHT).METHODS: Chronic portal hypertension was induced in Wistar rats by injection of carbon tetrachloride. After two weeks of cirrhosis formation, L-NMMA (25mg/kg) was injected into one group of cirrhotic rats via femoral vein and the experiment was begun immediately. Another group of cirrhotic rats was injected with anti-rat TNFα (300mg/kg) via abdominal cavity twice within 48h and the experiment was performed 24h after the second injection. The blood concentrations of TNFα, ET-1 and NO in portal vein and the nitric oxide synthase (NOS) activity in hepatic tissue were determined pre-and post-injection of anti-rat TNFα or LNMMA. Stroke volume (SV), cardiac output (CO), portal pressure (PP), superior mesenteric artery blood flow (SMA flow) and lilac artery blood flow (IAflow) were measured simultaneously. Acute portal hypertension was established in Wistar rats by partial portal-vein ligation (PVL). The parameters mentioned above were determined at 0.5h,24h, 48h, 72h and 120h after PVL. After the formation of stable PHT, the PVL rats were injected with anti-rat TNFα or L-NMMA according to different groups, the parameters mentioned above were also determined.RESULTS:In cirrhotic rats, the blood levels of TNFα, NO in portal vein and the liver NOS activity were significantly increased (P&lt;0.05) while the blood level of ET-1 was not statistically different (P&gt;0.05) from the control animals(477.67&#177;83.81pg/mL vs 48.87&#177;32.79pg/mL, 278.41&#177;20.11μmol/L vs 113.28&#177;14.51μmol/L, 1.81&#177;0.06μ/mg.prot vs 0.87&#177;0.03μ/mg.prot and 14.33&#177;4.42pg/mL vs8.72&#177;0.79pg/mL, respectively). After injection of anti-rat TNFα,the blood level of TNFα was lower than that in controls (15.17&#177;18.79pg/mL vs 48.87&#177;32.79pg/mL). The blood level of NO and the liver NOS activity were significantly decreased, but still higher than those of the controls. The blood level of ET-1 was not significantly changed. PP,SV,CO, SMAflow and IAflow were ameliorated. After injection of L-NMMA, the blood level of NO and the liver NOS activity were recovered to those of the controls. PP and CO were also recovered to those of the controls. SV, SMAflow and IAflow were ameliorated. In PVL rats, the blood levels of TNFα NO in portal vein and the liver NOS activity were gradually increased and reached the highest levels at 48h after PVL. The blood level of ET-1 among different staged animals was not significantly different from the control animals. PP among different staged animals (2.4&#177;0.18kPa at 0.5h, 1.56&#177;0.08kPa at 24h, 1.74&#177;0.1kPa at 48h,2.38&#177;0.05 kPa at 72h, 2.39&#177;0.16 kPa at 120h) was significantly higher than that in controls (0.9&#177;0.16kPa). After injection of anti-rat TNFα in 72h PVL rats, the blood level of TNFα was lower than that in controls (14&#177;14pg/mL vs 48.87&#177;32.79pg/mL). The blood level of NO and the liver NOS activity were significantly decreased, but still higher than those of the controls. The blood level of ET-1 was not significantly changed. PP was decreased from 2.38&#177;0.05kPa to 1.68&#177;0.12kPa, but significantly higher than that in controls. SV, CO, SMAflow and IAflow were ameliorated.After injection of L-NMMA in 72h PVL rats, the blood level of NO and the liver NOS activity were recovered to those of the controls. PP, SV, CO, SMAflow and IAflow were also recovered to those of the controls.CONCLUSION:NO plays a critical role in the development and maintenance of HC in acute PHT and is a key factor for maintenance of HC in chronic PHT. TNFα may not participate in the hemodynamic changes of HC directly, while play an indirect role by inducing the production of NO through activating NOS. No evidence that circulating ET-1 plays a role in both models of portal hypertension has been found.     

Effects of long-term tea polyphenols consumption on hepatic microsomal drug-metabolizing enzymes and liver function in Wistar rats

AIM: To investigate the effects of long-term tea polyphenols (TPs) consumption on hepatic microsomal drug-metabolizing enzymes and liver function in rats.METHODS: TPs were administered intragastrically to rats at the doses of 833 mg.kg-1.d-1 (n=20) and 83.3 mg.kg-1@d-1 (n=20) respectively for six months. Controlled group (n=20)was given same volume of saline solution. Then the contents of cytochrome P450, bS, enzyme activities of aminopyrine N-demethylase (ADM), glutathione S-trasferase (GST) and the biochemical liver function of serum were determined.RESULTS: The contents of cytochrome P450 and b5 in the livers of male rats in high dose groups (respectively 2.66±0.55,10.43±2.78 nmol.mg MS pro-1) were significantly increased compared with the control group (1.08±1.04, 5.51±2.98nmol.mg MS pro-1; P＜0.01, respectively). The enzymatic activities of ADM in the livers of female rats in high dose groups (0.91±0.08 mmol@mg MS pro-1min-1) were increased compared with the control group (0.82±0.08 mmol.mg MS pro-1.min-1; P＜0.05). The GST activity was unchanged in all treated groups, and the function of liver was not obviously changed.CONCLUSION: The antidotal capability of rats' livers can be significantly improved after long-term consumption of TPs.There are differences in changes of drug-metabolizing enzymes between the sexes induced by TPs and normal condition.     

Effect of resveratrol and in combination with 5-FU on murine liver cancer

AIM: To study the anti-tumor effect of resveratrol and in combination with 5-FU on murine liver cancer. METHODS: Transplantable murine hepatoma22 model was used to evaluate the anti-tumor activity of resveratrol (RES) alone or in combination with 5-FU in vivo. H22 cell cycles were analyzed with flow cytometry. RESULTS: Resveratrol could inhibit the growth of murine hepatoma22, after the mice bearing H22 tumor were treated with 10 mg/kg or 15 mg/kg resveratrol for ten days, and the inhibition rates were 36.3% (n = 10) and 49.3% (n = 9), respectively, which increased obviously compared with that in control group (85+/-22 vs 68+/-17, P<0.01). RES could induce the S phase arrest of H22 cells, and increase the percentage of cells in S phase from 59.1% (n = 9) to 73.5% (n = 9) in a dose-dependent manner (P<0.05). The enhanced inhibition of tumor growth by 5-FU was also observed in hepatoma22 bearing mice when 5-FU was administered in combination with 10 mg/kg resveratrol. The inhibition rates for 20 mg/kg or 10 mg/kg 5-FU in combination with 10 mg/kg resveratrol were 77.4% and 72.4%, respectively, compared with the group of 20 mg/kg or 10 mg/kg 5-FU alone, in which the inhibition rates were 53.4% and 43.8%, respectively (n = 8). There was a statistical significance between the combination group and 5-FU group. CONCLUSION: RES could induce the S phase arrest of H22 cells and enhance the anti-tumor effect of 5-FU on murine hepatoma22 and antagonize its toxicity markedly. These results suggest that resveratrol, as a biochemical modulator to enhance the therapeutic effects of 5-FU, may be potentially useful in cancer chemotherapy.     

Effect of hepatic glucose production on acute insulin resistance induced by lipid-infusion in awake rats

AIM: To explore the influence of hepatic glucose production on acute insulin resistance induced by a lipid infusion in awake rats. METHODS: A hyperinsulinaemic-euglycaemic clamp was established in awake chronically catheterized rats. Two groups of rats were studied either with a 4-h intraarterial infusion of lipid/heparin or saline. Insulin-mediated peripheral and hepatic glucose metabolism was assessed by hyperinsulinaemic-euglycaemic clamp combined with [3-^3H]-glucose infusion. RESULTS: During hyperinsulinaemic-euglycaemic clamp,there was a significant increase in plasma free fatty acid (FFA, from 741.9&#177;50.6 to 2346.44&#177;238.5μmol/L, P&lt;0.01) in lipid-infused group. The glucose infusion rates (GIR) in the lipid infusion rats, compared to control rats, were significantly reduced (200-240 min average: lipid infusion; 12.64&#177;1.5 vs control; 34.04&#177;1.6 mg/kg.min, P&lt;0.01), declining to - 35% of the corresponding control values during the last time of the clamp (240min: lipid infusion; 12.04&#177;1.9 vs control; 34.74&#177;1.7 mg/kg&#183;min, P&lt;0.0001). At the end of clamp study,the hepatic glucose production (HGP) in control rats was significantly suppressed (88%) from 19.04&#177;4.5 (basal) to 2.34&#177;0.9 mg/kg.min (P&lt;0.01). The suppressive effect of insulin on HGP was significantly blunted in the lipid-infused rats (200-240 min: from 18.74&#177;3.0 to 23.24&#177;3.1 mg/kg.min (P&lt;0.05). The rate of glucose disappearance (GRd) was a slight decrease in the lipid-infused rats compared with controls during the clamp.CONCLUSION: These data suggest that lipid infusion could induces suppression of hepatic glucose production, impairs the abilities of insulin to suppress lipolysis and mediate glucose utilization in peripheral tissue. Therefore, we conclude that lipid-infusion induces an acute insulin resistance in vivo.