Operational use of neem oil as an alternative anopheline larvicide. Part B: Environmental impact and toxicological potential

This study was conducted to investigate the preliminary environmental and mammalian toxicology of neem oil, temephos and chlorpyriphos-methyl/fenitrothion. Culex pipiens, Daphnia magna and Gambusia affinis were used to study environmental impact. A high level of toxicity was observed, with slight differences between organisms. The emulsifiers individually also displayed toxicity towards the tested organisms. Up to 90 days daily oral crude neem oil treatment (5 g/kg body weight) of laboratory mice did not cause any significant changes in weekly body weight gain, nor in serum liver damage indicators, direct bilirubin or total bilirubin. Blood parameters of treated mice up to 90 days were not statistically different from those of control mice. Neem oil could be used as an environmentally friendly alternative to the traditional chemical anopheline larvicides.

Effect of ingested heavy metals (Cd, Pb and Hg) on haematology and serum biochemistry in rabbits

In order to investigate the effects of exposure to possible environmental pollutants such as Cd, Pb and Hg on haematological and serum biochemistry values, New Zealand White female rabbits were treated orally with distilled water solutions of CdSO4 x H2O, Pb(NO3)2 and HgCl2 (n = 4/treatment) in concentrations of 2.3, 4.1, and 30 mg/kg dry matter, respectively, for 28 days. The initial concentrations of Cd, Pb, and Hg in serum were significantly increased by the treatment. Exposure to Pb significantly decreased the red blood cell (RBC) count, haemoglobin (Hgb) concentration and the haematocrit (Hct) value. The Zn-protoporphyrin concentration did not change as a result of Pb exposure. Pb and Hg loading significantly increased the aspartate aminotransferase (AST) activity. Alanine aminotransferase (ALT) activity was also increased by both Hg and Cd exposure. Comparing the treated and the control rabbits, all the trace elements studied significantly reduced the activity of enzymes in the pancreatic tissues. The haematological results indicate that hyperchromic macrocytic anaemia developed in rabbits treated with Pb. The increased activities of both AST and ALT indicate pathophysiological changes of the liver parenchyma, which was verified by focal fatty infiltration seen histopathologically. Cd exposure could exert a toxic effect on the kidneys, although the slight tubulonephrosis developed would not possibly affect the renal function. The reduced activities of amylase, trypsin, protease and lipase induced by Cd, Pb and Hg suggest toxicity to the pancreas.

Natural history of pruritus in primary biliary cirrhosis

The natural history of pruritus in primary biliary cirrhosis (PBC) remains poorly defined. The aim of this investigation was to evaluate outcomes of pruritus in clinical trials for ursodeoxycholic acid (UDCA). In a UDCA-placebo trial begun in 1988 (n = 180), a 55% prevalence rate for pruritus was observed. Serum alkaline phosphatase level and Mayo risk score were independent risk factors for pruritus (P < 0.0001). Among placebo-treated patients (n = 91), the annual risks for development or improvement/resolution of pruritus were 27% and 23%, respectively. For UDCA-treated patients (n = 89), a trend toward improvement in pruritus was observed after 1 year compared to placebo (30% vs. 23%, P = 0.08) but not at 2 or 3 years. In a 3-dose UDCA trial begun in 1995 (n = 155), the overall prevalence of pruritus was significantly lower at 37% when compared to UDCA-placebo participants (P < 0.001). Baseline serum alkaline phosphatase level and Mayo risk score were again independent risk factors for pruritus (P < 0.0001). Among 13 (3.9%) patients with refractory pruritus, symptom resolution (n = 5) or improvement (n = 8) was associated with the use of oral rifampin (300 or 600 mg daily). Two patients treated with rifampin developed biochemical evidence for hepatotoxicity necessitating drug withdrawal. Although less prevalent among recently diagnosed individuals, more than one third of PBC patients develop pruritus. No significant risk reduction in developing pruritus with UDCA therapy was observed compared to placebo-treated patients. The long-term administration of rifampin for refractory pruritus is associated with occasional hepatotoxicity.

Experimental hyperkalaemia in rabbits: effects of salbutamol and norepinephrine treatments on blood biochemistry and electrocardiography

The effects of salbutamol and norepinephrine on the electrocardiogram (ECG), serum potassium level and enzyme activities were studied in rabbits with hyperkalaemia; norepinephrine and salbutamol may be therapeutically useful. For induction of hyperkalaemia, 300 mM KCl solution was used and then isotonic saline solution containing 6 microg salbutamol and 3.9 microg norepinephrine per ml were administered. Norepinephrine and salbutamol decreased the serum potassium from 7.36 +/- 0.26 and 7.21 +/- 0.31 mmol/L to 5.62 +/- 0.27 and 4.35 +/- 0.33 mmol/L, respectively, and caused the ECG changes (flatness of P wave, widening of QRS complex and bradycardia) to return to the control conditions (time 0). Norepinephrine, but not salbutamol, decreased the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) to the control levels. These results suggest that monitoring of the enzyme activities might be useful as it yields indexes suitable for evaluating the therapeutic approach with norepinephrine in hyperkalaemia.

A randomized double-blind study of the short-time treatment of obese patients with nonalcoholic fatty liver disease with ursodeoxycholic acid

In order to determine the effect of ursodeoxycholic acid on nonalcoholic fatty liver disease, 30 patients with body mass indices higher than 25, serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) or gamma-glutamyltransferase (gamma-GT) at least more than 1.5 times the upper limit of normality, and hepatic steatosis demonstrated by ultrasonography were randomized into two groups of 15 patients to receive placebo or 10 mg kg-1 day-1 ursodeoxycholic acid for three months. Abdominal computed tomography was performed to quantify hepatic fat content, which was significantly correlated with histological grading of steatosis (r s = -0.83, P < 0.01). Patient body mass index remained stable for both groups throughout the study, but a significant reduction in mean ( +/- SEM) serum levels of ALT, AST and gamma-GT was observed only in the treated group (ALT = 81.2 +/- 9.7, 44.8 +/- 7.7, 48.1 +/- 7.7 and 52.2 +/- 6.3 IU/l at the beginning and after the first, second and third months, respectively, N = 14, P < 0.05). For the placebo group ALT values were 66.4 +/- 9.8, 54.5 +/- 7, 60 +/- 7.6 and 43.7 5 IU/l, respectively. No alterations in hepatic lipid content were observed in these patients by computed tomography examination (50.2 +/- 4.2 Hounsfield units (HU) at the beginning versus 51.1 +/- 4.1 HU at the third month). These results show that ursodeoxycholic acid is able to reduce serum levels of hepatic enzymes in patients with nonalcoholic fatty liver disease, but this effect is not related to modifications in liver fat content.

Decreased ratio of CD4/CD8 lymphocytes might be predictive for successful interferon alpha and lamivudine combined therapy in childhood chronic hepatitis B infection: A preliminary study

BACKGROUND

In the development of chronic hepatitis with hepatitis B virus infection and in response to therapy, the immune status of the infected host plays a critical role. In this study, immunological variables were assessed in patients before interferon alpha and lamivudine therapy to determine if any pretreatment immunological parameter could be an indicator of response to therapy in childhood chronic hepatitis B infection.

METHODS

Forty-four patients with chronic hepatitis B virus infection, aged 9.0 +/- 3.9 years, were enrolled in the study. The pretreatment clinical features, biochemical test results, histological activity indexes and immunological parameters were evaluated. All patients received interferon alpha for 6 months and lamivudine for 52 weeks. Four patients who could not be followed up were excluded from the study. The other 40 patients have been followed for a mean period of 27.5 +/- 9.7 months after therapy discontinuation.

RESULTS

Seventeen patients showed loss of hepatitis B early antigen (HBeAg) with appearance of anti-HBe (42.5%) and six of those who responded also showed loss of hepatitis B surface antigen (HBsAg) with the presence of anti-HBs (15%). Except elevated aspartate aminotransferase levels, there was no significantly correlation between response and sex, age, pretreatment duration of disease and histological activity indexes. Pretreatment immunoglobulins (Ig), IgG subclasses, complement C3, C4 and secretory IgA levels were also not found to be significantly related to response. The evaluation of lymphocyte subsets showed that therapy responders had significantly reduced pretreatment ratios of CD4/CD8+ lymphocytes due to prominent increased percentages of CD8+ cells. The other cellular immunity parameters and some cell surface adhesion molecules were similar in both groups.

CONCLUSION

This study emphasizes the importance of increased pretreatment CD8+ lymphocyte percentages leading to a significant decrease in CD4/CD8 ratio in chronic hepatitis B virus infection of childhood as an immunological factor predicting response to treatment.

Nicotinamide increases systemic vascular resistance in ovine endotoxemia

OBJECTIVE

The nuclear enzyme Poly(ADP-Ribose)-Polymerase (PARP) has been hypothesized as playing a major role in various forms of inflammation. PARP activation is induced by DNA strand breakage and can result in intracellular energy depletion and, ultimately, cell death. Further, it is thought to influence cardiovascular function and organ failure in endotoxemia. Here, we investigated the effect of the PARP inhibitor nicotinamide on cardiovascular and liver function in healthy and chronically endotoxemic sheep.

DESIGN

Prospective controlled trial.

SETTING

University research laboratory.

SUBJECTS

12 female adult sheep.

INTERVENTIONS

Six healthy sheep, instrumented for chronic study, received nicotinamide intravenously as a bolus of 40 mg/kg followed by a continuous infusion of 10 mg.kg(-1).h(-1); six animals received the vehicle. One hour after bolus application, a continuous infusion of endotoxin ( Salmonella typhosa, 10 ng.kg(-1).min(-1)) was started. Hemodynamic parameters were determined before and during endotoxemia.

MEASUREMENTS AND RESULTS

Treatment with nicotinamide resulted in a significantly higher systemic vascular resistance index and lower cardiac index in endotoxemic animals, but not in controls. It also attenuated endotoxin-induced increase in gamma-glutamyl transferase.

CONCLUSIONS

The PARP inhibitor nicotinamide attenuates impairment of cardiovascular function during endotoxemia. In addition, PARP activation may be involved in endotoxin-induced liver injury.

Anti-inflammatory and hepatoprotective activity of peh-hue-juwa-chi-cao in male rats

Peh-hue-juwa-chi-cao (PHJCC) is a common commercial name for the herbal extract of either Hedyotis diffusa (HD), H. corymbosa (HC), or Mollugo pentaphylla (MP). The present study was carried out to investigate the anti-inflammatory and hepatoprotective effects of these three extracts in rats. The results indicated that extracts of HC, HD and MP possess anti-inflammatory activity, and that MP has the greatest inhibition against carrageenan-induced paw edema. In the hepatoprotective study, results indicated that the three plant extracts significantly reduced the acute elevation of serum glutamate oxalate transaminase (sGOT) and serum glutamate pyruvate transaminase (sGPT) concentration, and alleviated the degree of liver damage 24 hours after the intraperitoneal administration of hepatotoxins.

Genomic effect of glucocorticoids on enzymes of intermediary metabolism in Oreochromis mossambicus

The present study examined the effect of long-term treatment with cortisol and corticosterone on enzymes of intermediary metabolism, namely malic enzyme (ME), glucose-6-phosphate dehydrogenase (G6PDH), isocitrate dehydrogenase (ICDH), glucose 6 phosphatase (G-6-Pase), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) in Oreochromis mossambicus. Cortisol and corticosterone regulate intermediary metabolism in the liver of O. mossambicus as evidenced by changes in the activity pattern of gluconeogenic and lipogenic enzymes and amino-transferases. The long-term in vivo ip administration of glucocorticoids (GCs) suggests hyperglycemic, gluconeogenic, and antilipogenic roles of the hormones in O. mossambicus. The genomic mode of action of GCs is well established in the present study since the long-term treatment is sensitive to the action of transcription and translation inhibitors.

Mitigation of thyroxine-induced hyperglycaemia by two plant extracts

Extracts of Trigonella foenum-graecum (TFG) seed and Allium sativum (AS) bulb were evaluated for their efficacy to ameliorate l-thyroxine (l-T4) induced hyperglycaemia in rats. Simultaneously, the serum cholesterol concentration, a supporting parameter for thyroid function, was also estimated. Thyroxine treatment in rats (300 microg/kg b. wt./day) increased the levels of both the thyroid hormones, namely thyroxine (T4) and tri-iodothyronine (T3) with a concomitant elevation in serum glucose concentration and a reduction in serum cholesterol level. Administration of TFG (220 mg/kg/day) and AS (500 mg/kg/day) extracts in hyperthyroid animals decreased the serum glucose concentration as well as the serum thyroid hormones. For comparison, propyl thiouracil (PTU), an antithyroid compound, was used as the standard at a daily dose of 10 mg/kg. The reductions in serum glucose and thyroid hormone concentrations in the plant extract treated groups were comparable to that in PTU treated animals. Our findings indicate that TFG seed and AS bulb extracts may prove to be effective in the treatment of thyroxine-induced hyperglycaemia.

Protective effect of Mangifera indica L. extract (Vimang) on the injury associated with hepatic ischaemia reperfusion

The effect of Mangifera indica L. extract (Vimang) on treatment of injury associated with hepatic ischaemia/reperfusion was tested. Vimang protects from the oxidative damage induced by oxygen-based free radicals as shown in several in vitro test systems conducted. The ability of Vimang to reduce liver damage was investigated in rats undergoing right-lobe blood fl ow occlusion for 45 min followed by 45 min of reperfusion. The ischaemia/reperfusion model leads to an increase of transaminase (ALT and AST), membrane lipid peroxidation, tissue neutrophil in filtration, DNA fragmentation, loss of protein -SH groups, cytosolic Ca2+ overload and a decrease of catalase activity. Oral administration of Vimang (50, 110 and 250 mg/kg, b.w.) 7 days before reperfusion, reduced transaminase levels and DNA fragmentation in a dose dependent manner (p < 0.05). Vimang also restored the cytosolic Ca2+ levels and inhibited polymorphonuclear migration at a dose of 250 mg/kg b.w., improved the oxidation of total and non protein sulfhydryl groups and prevented modification in catalase activity, uric acid and lipid peroxidation markers (p < 0.05). These data suggest that Vimang could be a useful new natural drug for preventing oxidative damage during hepatic injury associated with free radical generation.

Effect of isoproterenol on lipid peroxidation and antioxidant enzymes of myocardial tissue of mice and protection by quinidine

Administration of isoproterenol to mice at a dose of 30 mg/100 g body weight for 3 consecutive days at an interval of 24 h induced lipid peroxidation in cardiac tissue and exhibited a significantly elevated serum glutamate oxaloacetate transaminase (SGOT) level. Increased superoxide dismutase (SOD) activity with a concomitant decrease in catalase activity has also been observed in cardiac tissue with isoproterenol treatment. Quinidine, a class I antiarrhythmic agent has been found to exhibit a protective role in isoproterenol induced myocardial ischaemia. Cardiac tissue of quinidine treated mice showed reduction of lipid peroxidation reaction. In addition, quinidine treatment is found to influence the cardiac antioxidant enzymes - catalase and SOD. The decrease of SOD activity and increase of catalase activity suggests that quinidine also exerts an 'indirect antioxidant' effect in protecting the myocardial tissue from reactive oxygen species. Furthermore, our current in vitro studies with quinidine have clearly shown in this work that it possesses a very convincing hydroxyl radical scavenging potential with almost no ability to scavenge superoxide anion and hydrogen peroxide (H2O2) in vitro. Thus, our present investigation suggests that quinidine, when administered to mice, strengthens the antioxidant defense system to resist the free radical induced damage brought about by isoproterenol induced ischaemic condition.

Methylglyoxal-induced glycation affects protein topography

Methylglyoxal is a metabolic byproduct that is elevated in diabetic tissue. We examined the effects of methylglyoxal on cytosolic aspartate aminotransferase (cAAT), which is an enzyme previously shown to be modified by glyceraldehyde, acrolein, and ribose 5-phosphate. In the present study we observed that methylglyoxal caused real-time changes in tryptophan (intrinsic) fluorescence. Millimolar concentrations of methylglyoxal predominately decreased the fluorescence emission at 388 nm. While micromolar concentrations also decreased emission at 388 nm, low levels of methylglyoxal caused a prominent redshift in the wavelength of maximal emission. The changes in intrinsic fluorescence reflect definable changes in protein topography. These observations are consistent with a change in conformation that is more compact than that of native cAAT, suggesting that intramolecular cross-links (i.e., lysine-lysine) or hydrophobic pockets (i.e., carboxyethyl-lysines) were formed. Methylglyoxal also inhibited activity, and the inhibition correlated with the methylglyoxal-induced change in protein conformation.

Preservation of neurological functions by nitric oxide synthase inhibitors following hemorrhagic shock

Excessive production of nitric oxide (NO) as result of inducible nitric oxide synthase (iNOS) induction has been implicated in the pathophysiology of hemorrhagic shock. Our aim was to study the effect of iNOS inhibitors, L-canavanine (50mg/kg) and N(G)-nitro- L-arginine methyl (L-NAME, 10mg/kg) and a resuscitation fluid, lactated Ringer's solution (3 times amount of blood lost), on survivability and neurological functions in rodents subjected to hemorrhagic shock. L-canavanine-treated rats had significantly higher survival rates (75%) compared to L-NAME-treated rats (44%) and lactated Ringer's solution-treated rats (40%), 72 h following hemorrhagic shock. A marked increase in the neurological performance was observed in L-canavanine-treated rats over the three-day period. Histological examinations also showed a reduction of degenerating neurons in L-canavanine-treated rats when compared to L-NAME-, lactated Ringer's solution- or un-treated rats. Mean arterial blood pressure (MABP), nitrate/nitrite level, glutamic oxalacetic transaminase (GOT) level, and blood gases were also significantly improved in L-canavanine-treated rats when compared to those of L-NAME-, lactated Ringer's solution- or un-treated rats. In conclusion, L-canavanine-treated rats were able to improve survivability, attenuate organ damage, and improve neurological outcome when compared to other treatment groups. It is therefore suggest that L-canavanine may be beneficial as a potentially useful therapeutic agent in treating neurological deficit as a result of hemorrhagic shock.

Chronic graft-versus-host disease complicated by acute hepatitis B

We observed a 45-year-old man with acute hepatitis B while receiving treatment of chronic graft-versus-host disease (GVHD) of the liver. When he developed a sudden elevation of serum aminotransferases 17 months after bone marrow transplantation, he was under immunosuppressive therapy consisting of cyclosporin A against chronic GVHD of the liver. Serologic tests for hepatitis B virus (HBV) showed no reactivation but de novo acute infection. The serum levels of aminotransferases after elevation of biliary tract enzymes increased mildly. However, icterus was not observed in his sequential course. A liver biopsy specimen revealed mild acute liver injury accompanied by slight degeneration of bile ducts. It is presumed that owing to immunosuppressive therapy, his liver dysfunction was relatively mild, and the hepatitis became quiescent without becoming serious. On the other hand, the serum of the patient remained hepatitis B surface antigen positive for more than 1 year after the onset of the hepatitis, which suggested chronicity of HBV infection.

Diphenhydramine and hyaluronic acid derivatives reduce adnexal adhesions and prevent tubal obstructions in rats

OBJECTIVE

The purpose of this study is to investigate the effects of diphenhydramine-HCl and Na-hyaluronate derivatives on the development of postoperative peritoneal adhesion and tubal obstruction.

STUDY DESIGN

Forty female rats of Sprague-Dawley type were used in the study. The rats were divided into four groups, each comprising 10 subjects. After all the rats were anaesthetized with 50mg/kg ketamine HCl, their abdomens were opened with a lower midline incision. Injury was induced on the right pelvic peritoneum and on the peritoneal surface of left uterine tube. No additional procedure was applied to the first group. 10 mg/kg diphenhydramine-HCl was given to the second group intravenously. In the third group, 0.25 mg/kg Orthovisc, a Na-hyaluronate derivative was diluted with 2 ml physiological saline and poured into the abdomen. For the fourth group, Seprafilm, a Na-hyaluronate derivative was covered in a layer of 0.7 cm x 3 cm over the left uterine tube. After 14 days, the rats were anaesthetized with ketamine HCl again, and 5 cm(3) blood sample was taken with cardiac puncture. The abdomen was opened with an incision transverse to the upper end of the midline incision, and the presence of adhesions was investigated. Detected adhesions were staged according to the Mazuji classification. Tubal patencies were inspected by injecting methylene blue from the uterine corpus into the lumen using an injector. A piece of abdominal wall of 4 cm x 4 cm was removed by extending the incision in the reverse U shape. The tensile strength and bursting pressure of the suture line were determined using the Peacock method. One gram of tissue was taken from the incision line, and hydroxyproline levels were determined by the Bergman-Loxley method. Aspartate aminotransferase (AST) levels were measured.

RESULTS

All of the rats completed the study. AST levels, tissue hydroxyproline levels and tensile strength and bursting pressure test results were found to be similar in all groups. While adhesion rates in the groups were 100, 40, 40 and 30%, respectively, adhesion stages were found to be, respectively as 2.1+/-1.7, 0.6+/-0.67, 0.6+/-0.67 and 0.5+/-0.85. Adhesion stages in the study groups were significantly lower (P<0.05). Tubal obstruction rates were found to be 70, 30, 30 and 20%, respectively.

CONCLUSION

Diphenhydramine, Orthovisc and Seprafilm significantly reduce postoperative peritoneal adhesion development, and they allow the uterine tubes to remain open.

[Optimization of diet therapy in patients with gallstones complicated with obesity and impaired glucose tolerance]

It was investigated the influence of a diet with lower glycaemic index on clinico-metabolic parameters in obese patients with gallstones and impaired glucose tolerance. The results investigations indicated that the lowering of glycaemic index and the caloric reduction of diet have a beneficial effects on dynamic of parameters of functional status of liver and gallbladder. It was noted the increase of medical effect of diet in correction of obesity and impaired parameters of carbohydrate and lipid metabolism in this patients in process of dietotherapy.

Idraparinux and liver enzymes: observations from the PERSIST trial

A potential influence of idraparinux--a synthetic analogue of the pentasaccharide sequence in heparins--on plasma liver enzyme levels was analysed in 37 patients suffering from deep vein thrombosis and participating in the PERSIST trial. Plasma gamma-glutamyl-transferase, aspartate aminotransferase and alanine aminotransferase were determined prior to enoxaparin treatment (screening), prior to randomization (baseline) and once weekly during the 12-week treatment period. Patients were initially treated with weight-adjusted enoxaparin for 4-7 days and then randomized to either idraparinux (2.5, 5, 7.5 or 10 mg) or warfarin. Gamma-glutamyl-transferase was significantly increased after administration of enoxaparin at the baseline visit (P = 0.004) and in week 2 (P = 0.009) to return to screening levels in week 3 for the remaining study period (all P > 0.05). Aspartate aminotransferase (P = 0.001) and alanine aminotransferase (P < 0.001) were significantly increased at the baseline visit and returned to screening values at week 2 for the remaining study period (all P > 0.05). There was no significant difference between the mean values of plasma liver enzymes of the four idraparinux groups and the warfarin group in all 13 measurements. We concluded that idraparinux in contrast to enoxaparin does not increase plasma liver enzymes significantly.

Age-associated loss of immunomodulatory protection by granulocyte-colony stimulating factor in endotoxic rats

Elderly patients have a higher incidence of morbidity and mortality due to infectious diseases. Because most immune functions in the elderly differ compared with those in younger subjects, we studied the effect of the immunomodulating agent G-CSF on endotoxic liver injury and cytokine release in an aging animal model of acute sepsis. Young (3-month-old), mature (12-month-old), and senescent (24-month-old) male Sprague-Dawley rats (n = 6 each) were treated with bacterial endotoxin for 6 h. Age-matched groups of animals (n = 6 each) received G-CSF (200 microg/kg i.v.) 1 h prior to endotoxin. LPS-induced hepatic toxicity, as assessed in vivo by nutritive perfusion failure, intravascular leukocyte accumulation, biliary excretion dysfunction, and liver enzyme release, was significantly more pronounced in mature and old animals when compared with young animals. Concomitantly, mature but, in particular, senescent endotoxic animals exhibited 2- to 14-fold higher plasma levels of TNF-alpha, IL-1beta, IL-6, IL-10, and Rantes than young endotoxic rats. The percentage of G-CSF receptor surface expression on neutrophils did not significantly differ between young, mature, and senescent animals (36%-46%) and was found comparably down-regulated at 6 h after LPS exposure (15%-19%). Kupffer cell activation, i.e., clearance of intravascularly applied fluorescent latex beads, did not differ between the LPS-exposed age groups. G-CSF dampened LPS-induced Kupffer cell activation, and significantly reduced plasma cytokine levels in young and mature, but not in senescent animals. Thereby, G-CSF caused attenuation of hepatic tissue injury in all except the senescent endotoxic animals. In summary, our results show an age-dependent increase in hepatic LPS toxicity. Because flow cytometric analysis of G-CSF receptor expression disproved that cytokinemia-induced down-regulation of G-CSF receptors might account for the unresponsiveness to G-CSF in the senescent animals, other homeostatic regulatory mechanisms appear to undergo changes with age that bring out a disrupted balance between inflammatory cytokines with unresponsiveness to G-CSF and, thus, compromised host defense mechanisms in the elderly.

Hepatoprotective effects of 18beta-glycyrrhetinic acid on carbon tetrachloride-induced liver injury: inhibition of cytochrome P450 2E1 expression

The protective effects of 18beta-glycyrrhetinic acid (GA), the aglycone of glycyrrhizin (GL) derived from licorice, on carbon tetrachloride-induced hepatotoxicity and the possible mechanisms involved in this protection were investigated in mice. Pretreatment with GA prior to the administration of carbon tetrachloride significantly prevented an increase in serum alanine, aspartate aminotransferase activity and hepatic lipid peroxidation in a dose-dependent manner. In addition, pretreatment with GA also significantly prevented the depletion of glutathione (GSH) content in the livers of carbon tetrachloride-intoxicated mice. However, reduced hepatic GSH levels and glutathione-S-transferase activities were unaffected by treatment with GA alone. Carbon tetrachloride-induced hepatotoxicity was also prevented, as indicated by a liver histopathologic study. The effects of GA on the cytochrome P450 (P450) 2E1, the major isozyme involved in carbon tetrachloride bioactivation, were also investigated. Treatment of mice with GA resulted in a significant decrease of the P450 2E1-dependent hydroxylation of p-nitrophenol and aniline in a dose-dependent manner. Consistent with these observations, the P450 2E1 expressions were also decreased, as determined by immunoblot analysis. GA also showed antioxidant effects upon FeCl(2)-ascorbate-induced lipid peroxidation in mice liver homogenate and upon superoxide radical scavenging activity. These results show that protective effects of GA against the carbon tetrachloride-induced hepatotoxicity may be due to its ability to block the bioactivation of carbon tetrachloride, primarily by inhibiting the expression and activity of P450 2E1, and its free radical scavenging effects.

New potential nonsteroidal anti-inflammatory drugs with antileukotrienic effects: influence on model proteins with catalytic activity

Unspecific and side effects caused by interaction with proteins belong to common problems of many structures synthesized as potential medicaments. Possible in vitro interactions with proteins of a group of phenylsulfonyl benzoic acid derivatives (VUFB 19363, 19369, 19370, 19371, and 19760) as new potential anti-inflammatory compounds with anti-leukotrienic activities were studied in the present work. Three purified enzymes were used as model proteins with catalytic activities: Pig heart aspartate aminotransferase (AST, EC 2.6.1.1), alanine aminotransferase (ALT, EC 2.6.1.2), and glutamate decarboxylase (GAD, EC 4.1.1.15) from E. coli. Catalytic activities during incubation of individual compounds (6 x 10(-5) M solution to 5 x 10(-2) M suspension) at 37 degrees C with enzymes served as criteria of stability and function of the proteins. No immediate influence of any compound studied on enzyme activities was found. Aminotransferase activities were not affected even during incubation up to 20 d. In the case of GAD, the compounds VUFB 19369, 19370, 19371, and 19760 had stabilizing influence on GAD activity during incubation at enzyme concentrations of 11.25 and 5.62 mg prot/l. The lack of an immediate effect of compounds and the stability of enzymes during incubation them are favorable and support the prospective of the compounds as potential drugs.

[Adriamycin thermotherapy through hepatic artery for model of VX2 carcinoma in rabbit liver]

BACKGROUND & OBJECTIVE

It was reported that heating can enhance sensitivity of rabbit VX2 cell to adriamycin and increase intracellular concentration of adriamycin. This study was designed to evaluate the anti-tumor effects of interventional hyperthermia and interventional chemotheramotherapy on VX2 carcinoma in rabbit liver.

METHODS

VX2 carcinoma cells were surgically implanted into the right liver lobe of 60 male New Zealand white rabbits, which were randomly divided into 4 groups(15 rabbits per group). To inject physiological saline(37 degrees C), adriamycin (37 degrees C), physiological saline(60 degrees C), and adriamycin (60 degrees C) in different groups via hepatic artery of the rabbits with liver cancer. One week later, to observe the volume of tumor, the serum level of aspartate transaminase(AST), and observe the survival period of VX2 rabbits.

RESULTS

In group of ADM(60 degrees C), the tumor growth rate (0.53 +/- 0.21)% was significantly lower than group 2(1.09 +/- 0.26)%, group 3(3.32 +/- 1.28)%, and group 4(3.48 +/- 1.17)% (P < 0.05, P < 0.05, P < 0.01, respectively). The survival period of adriamycin (60 degrees C) group (50.0 +/- 2.0)d was significantly higher than the untreated control group (40.5 +/- 3.0)d, (P < 0.05). The serum level of AST of TNP-470 with lipiodol group was not higher than the other treated groups(P > 0.05), but being significantly higher than the untreated control group after treated(P < 0.05).

CONCLUSION

Adriamycin (60 degrees C) greatly decreases the tumour growth rate, and prolongs the survival period.

Endotoxin potentiates the hepatotoxicity of cocaine in male mice

Cocaine produces hepatotoxicity by a mechanism that remains undefined but that has been linked to its oxidative metabolism. Endotoxin (lipopolysaccharide, LPS) is also a well-known cause of hepatic damage, where exposure to non-injurious doses of LPS increases the toxicity of certain hepatotoxins. This study was conducted to investigate the possible potentiation of cocaine-mediated hepatotoxicity (CMH) by LPS. Male CF-1 mice were administered oral cocaine hydrochloride for 5 consecutive days at a dose of 20 mg/kg with and without 12 x 10(6) EU LPS/kg given intraperitoneally 4 h after the last cocaine injection. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured as markers of liver injury. Blood and liver glutathione (GSH) levels were determined, as well as the activities of glutathione peroxidase (GPx) and catalase (CAT). In addition, the activity of liver glutathione reductase (GRx) was measured. The results demonstrate that endotoxin potentiated the hepatotoxicity of cocaine. Serum ALT and AST were significantly elevated with the combined cocaine and LPS treatment versus all other treatments. While cocaine alone resulted in centrilobular necrosis, the cocaine and LPS combination produced submassive necrosis. The increased hepatic GSH content and GRx activity observed with cocaine alone were not observed with the combination treatment, rendering the liver more susceptible to oxidative stress. Moreover, there was a significant decrease in the activities of hepatic GPx and CAT, particularly with the combination treatment. In conclusion, this study demonstrates that LPS potentiates the hepatotoxicity of cocaine as revealed by an array of biochemical and morphological markers.

[Effects of selenium and fluoride on apoptosis and lipid peroxidation in human hepatocytes]

OBJECTIVE

To study the influence of selenium and fluoride on apoptosis and lipid peroxidation in human hepatocytes in vitro.

METHODS

The apoptosis, cell cycle, GSH content and lipid peroxides (LPO) level in human hepatocytes, LPO level and LDH, AST and ALT activity in cell culture supernatants were investigated after hepatocytes were incubated with selenium and/or fluoride for around 12 hours periods in vitro.

RESULTS

The percentage of hepatocyte apoptosis bodies (15.557 +/- 2.056)%, the number of cells in S phase (4.823 +/- 0.454)% and LPO level in liver tissue and supernatant [(2.884 +/- 0.589) and (3.547 +/- 0.561) nmol/L MDA/mg.prot, respectively], AST and LDH activity in supernatants (91.1 +/- 36.4 and 140.4 +/- 7.6 U/L, respectively) in the fluoride treated group was higher than the control group [(10.313 +/- 1.023)%, (3.253 +/- 0.743)%, (1.473 +/- 0.401) nmol/L MDA/mg.prot, (1.694 +/- 0.443) nmol/L MDA/mg.prot, (54.5 +/- 3.2) U/L and (126.4 +/- 2.6) U/L, respectively], The GSH content in live tissue [(4.225 +/- 0.781) microgram/mg.prot] is lower than control group [(7.595 +/- 1.042) microgram/mg.prot]. Selenium treatment reduced these kinds of toxicity of fluoride through raising GSH content, reducing LPO level, LDH and AST activity and percentage of apoptosis bodies.

CONCLUSIONS

Selenium can antagonist apoptosis and lipid peroxidation of hepatocytes induced by fluoride.