Intraperitoneal Alpha-Radioimmunotherapy of Advanced Ovarian Cancer in Nude Mice Using Different High Specific Activities

Background

The aim of this study was to investigate the therapeutic efficacy of advanced ovarian cancer in mice, using α-radioimmunotherapy with different high specific activities. The study was performed using the monoclonal antibody (mAb) MX35 F(ab′)2 labeled with the α-particle emitter ²¹¹At.

Methods

Animals were intraperitoneally inoculated with ≥1 × 10⁷ cells of the ovarian cancer cell line NIH:OVCAR-3. Four weeks later 9 groups of animals were given 25, 50, or 400 kBq ²¹¹At-MX35 F(ab′)2 with specific activities equal to 1/80, 1/500, or 1/1200 (²¹¹At atom/number of mAbs) for every activity level respectively (n = 10 in each group). As controls, animals were given PBS or unlabeled MX35 F(ab′)2 in PBS (n = 10 in each group). Eight weeks after treatment the animals were sacrificed and the presence of macroscopic tumors was determined by meticulous ocular examination of the abdominal cavity. Cumulated activity and absorbed dose calculations on tumor cells and tumors were performed using in house developed program. Specimens for scanning electron-microscopy analysis were collected from the peritoneum at the time of dissection.

Results

Summing over the different activity levels (25, 50, and 400 kBq ²¹¹At-MX35 F(ab′)2) the number of animals with macroscopic tumors was 13, 17, and 22 (n = 30 for each group) for the specific activities equal to 1/80, 1/500, or 1/1200, respectively. Logistic-regression analysis showed a significant trend that higher specific activity means less probability for macroscopic tumors (P = 0.02).

Conclusions

Increasing the specific activity indicates a way to enhance the therapeutic outcome of advanced ovarian cancer, regarding macroscopic tumors. Further studies of the role of the specific activity are therefore justified.

Quantitative trait locus analysis of neointimal formation in an intercross between C57BL/6 and C3H/HeJ apolipoprotein E-deficient mice

BACKGROUND

Inbred mouse strains C57BL/6J (B6) and C3H/HeJ (C3H) exhibit marked differences in neointimal formation after arterial injury when deficient in apolipoprotein E (apoE(-/-)) and fed a Western diet. Quantitative trait locus (QTL) analysis was performed on an intercross between B6.apoE(-/-) and C3H.apoE(-/-) mice to determine genetic factors contributing to the phenotype.

METHODS AND RESULTS

Female B6.apoE(-/-) mice were crossed with male C3H.apoE(-/-) mice to generate F(1)s, which were intercrossed to generate 204 male F(2) progeny. At 10 weeks of age, F(2)s underwent endothelium denudation injury to the left common carotid artery. Mice were fed a Western diet for 1 week before and 4 weeks after injury and analyzed for neointimal lesion size, plasma lipid and MCP-1 levels. One significant QTL, named Nih1 (61cM, LOD score: 5.02), on chromosome 12 and a suggestive locus on chromosome 13 (35cM, LOD: 2.67) were identified to influence lesion size. One significant QTL on distal chromosome 1 accounted for major variations in plasma non-HDL cholesterol and triglyceride levels. Four suggestive QTLs on chromosomes 1, 2, and 3 were detected for circulating MCP-1 levels. No correlations were observed between neointimal lesion size and plasma lipid levels or between lesion size and plasma MCP-1 levels.

CONCLUSIONS

Neointimal formation is controlled by genetic factors independent of those affecting plasma lipid levels and circulating MCP-1 levels in the B6 and C3H mouse model.

Mouse Single Oral Dose Toxicity Study of DHU001, a Polyherbal Formula

This study was conducted to obtain acute information of the oral dose toxicity of DHU001, a polyherbal formula in male and female mice. In order to calculated 50% lethal dose (LD50) and approximate lethal dose (LD) , test material was once orally administered to male and female ICR mice at dose levels of 2000, 1000, 500, 250 and 0 (vehicle control) ml/kg (body weight) . The mortality and changes on body weight, clinical signs, gross observation, organ weight and histopathology of principle organs were monitored 14 days after treatment with DHU001. We could not find any mortalities, DHU001 treatment-related clinical signs, changes on the body and organ weights, gross and histopathological findings. The results obtained in this study suggest that LD50 and approximate LD in mice after single oral dose of DHU001 were considered over 2000 mg/kg in both female and male mice.

Intermittent feeding attenuates clinical course of experimental autoimmune encephalomyelitis in C57BL/6 mice

Multiple Sclerosis (MS) is an autoimmune inflammatory, demyelinating disease of human central nervous system. Experimental Autoimmune Encephalomyelitis (EAE) is the commonly used animal model of MS. Calorie restriction has been found to reduce inflammation and autoimmune responses and promote neuroprotection. In this study we evaluated the effects of intermittent feeding protocol of the calorie restriction in a mouse model of EAE. Fifty four female mice (C57BL/6) were used in this study. The animals were divided into two dietary groups: ad libitum (AL) (n = 29) with free access to food and water and intermittent feeding (IF) (n = 25) with access to food on alternate days. After 8 weeks, EAE was induced in animals by immunization with MOG antigen (Hooke labs, Lawrence, MA, USA) subcutaneously. AL and IF groups were then further divided into two groups each: AA (ad libitum until the end of study) (n = 16) and AI (subjected to intermittent feeding regimen after immunization day) (n = 13). The IF group was divided into II (continued intermittent feeding regimen until the end of study) (n = 13) and IA (changed to AL regimen after immunization day) (n = 12). All the animals were behaviorally monitored for 35 days after immunization and observed daily for the signs and severity of disease with EAE scoring scale [0-5] and cumulative disease index (CDI) score. Intermittent feeding significantly reduced the incidence of EAE in IF groups (AI 0%, II 18.5%, IA 22.2%, p < 0.05). In addition, intermittent feeding significantly delayed the onset of EAE in AI group (p < 0.05) and also, intermittent feeding significantly reduced the severity of disease in II and IA groups (AA vs. II, p < 0.05 & AA vs. IA p < 0.05) groups. The CDI was also significantly reduced in intermittent feeding fed groups [AI, II and IA compared to AA group (P < 0.05, <0.01, <0.05 respectively)]. Intermittent feeding regimen protocol of the calorie restriction significantly suppressed EAE incidence, induction, and severity. The results of this study suggest possible role of intermittent feeding in the treatment of Multiple Sclerosis patients.

Micronucleus Test of DHU001, a Polyherbal Formula, in Bone Marrow Cells of Male ICR Mice

The genotoxic effects of DHU001, a polyherbal formula were evaluated using the mouse micronucleus test. DHU001 was administered once a day for 2 continuous days by oral gavage to male ICR mice at doses of 2000, 1000 and 500 mg/kg. Cyclophosphamide was used as a known geno-toxic agent in a positive control. The appearance of a micronucleus is used as an index for genotoxic potential. In addition, the changes on the total white blood cells and differential counts on the lymphocytes, neutrophils, eosinophils, basophils and monocytes in the prepared blood smears were also conducted to observe the possible immunosuppression. The results indicats that DHU001 showed no genotoxicity effects up to 2000 mg/kg dosing levels and did not influenced on the total white blood cells and differential counts. In addition, it is also considered that there were no problems from cytotoxicity of DHU001 tested in this study because the polychromatic erythrocyte ratio was detected as > 0.41 in all tested groups.

Significance of syndecan-1 expression in dextran sulfate sodium-induced colitis that progresses to chronicity in mice

AIM: To investigate the expression of syndecan-1 (SDC-1) in dextran sodium sulphate (DSS)-induced colitis that progresses to chronicity in mice and explore the role of SDC-1 in the progression of colitis.

METHODS: Fifty-four C57BL/6 mice were equally divided into control group and model group. The model group was fed 3% DSS ad libitum for 5 days, followed by administration of distilled water for 2 weeks to induce acute colitis that progressed to chronic inflammation. The control group was only fed distilled water. Mice were killed on days 5, 12 and 19, respectively. The histological changes in the colon were observed and scored under light microscopy. The expression of SDC-1 and interleukin-8 (IL-8) mRNAs as well as SDC-1 protein in colonic tissue was detected by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry, respectively.

RESULTS: The histological scores on days 5, 12 and 19 were significantly higher in the model group than in the control group (2.17 ± 1.03, 2.60 ± 1.73 and 1.18 ± 0.75 vs 0.04 ± 0.13, respectively; all P < 0.05). The expression levels of SDC-1 mRNA and protein in the colon at all time points were significantly lower in the model group than in the control group (mRNA: 1.58 ± 0.13, 1.39 ± 0.17 and 1.78 ± 0.08 vs 2.12 ± 0.03, respectively; all P < 0.05; protein: 1.59 ± 0.12, 1.43 ± 0.12 and 1.81 ± 0.10 vs 2.20 ± 0.04, respectively; all P < 0.01). The expression levels of IL-8 mRNA in the colon at all time points were significantly higher in the model group than in the control group (1.20 ± 0.15, 1.53 ± 0.05 and 1.65 ± 0.04 vs 1.02 ± 0.08, respectively; all P < 0.01).

CONCLUSION: The reduced severity of colitis is associated with downregulated SDC-1 mRNA and protein expression in the colon of mice. The downregulation of SDC-1 mRNA and protein may be associated with increased IL-8 mRNA level.

Effect of morphine on Mycobacterium smegmatis infection in mice and macrophages

The immunomodulatory effects of opioids are known in various infections. However, little is known about the effects of opioids in tuberculosis (TB). In the present study, we report the effects of morphine in Mycobacterium smegmatis infection in mice and macrophages. Morphine exerted a dose-dependent suppression of infection in vivo: 50 and 100 mg/kg morphine exerted significant (P<0.05) suppression whereas 5 mg/kg morphine showed no effect. Analogous to the in vivo effects, incubation of M. smegmatis-infected mouse peritoneal macrophages with morphine (100 μM) showed significant reduction in intramacrophage CFU counts. However, morphine did not show any direct antimycobacterial activity in broth dilution assay upto 100 μM concentration. Further, morphine-induced intramacrophage killing of M. smegmatis was abrogated by naloxone and aminoguanidine indicating the involvement of opioid-receptor activation and nitric oxide production in protective effects of morphine. In conclusion, morphine suppressed the progression of experimental TB in both mice and macrophage models.

The Acute Liver Injury in Mice Caused by Nano-Anatase TiO2

Although it is known that nano-TiO2or other nanoparticles can induce liver toxicities, the mechanisms and the molecular pathogenesis are still unclear. In this study, nano-anatase TiO2(5 nm) was injected into the abdominal cavity of ICR mice for consecutive 14 days, and the inflammatory responses of liver of mice was investigated. The results showed the obvious titanium accumulation in liver DNA, histopathological changes and hepatocytes apoptosis of mice liver, and the liver function damaged by higher doses nano-anatase TiO2. The real-time quantitative RT-PCR and ELISA analyses showed that nano-anatase TiO2can significantly alter the mRNA and protein expressions of several inflammatory cytokines, including nucleic factor-κB, macrophage migration inhibitory factor, tumor necrosis factor-α, interleukin-6, interleukin-1β, cross-reaction protein, interleukin-4, and interleukin-10. Our results also implied that the inflammatory responses and liver injury may be involved in nano-anatase TiO2-induced liver toxicity.

Establishment of a mouse model of stomach infection with candida albicans

AIM: To establish a mouse model of stomach with candida albicans infection on hypoimmunity and ulceric mouse.

METHODS: Kunming mice were randomly divided into 3 groups. Mice in control group were given 0.5 mL 5.5 × 10¹² candida albicans suspension by gastric intubation; mice in control group Ⅱ were given cyclophosphamide (40 g/L) through intraperitoneal injection by 0.02 mL per gram (weight) and lavaged with 0.5 mL 3 g/L glacial acetic acid; mice in model group were first lavaged in the same way as control group Ⅱ, then 2 hours later, were given intragastric administration with 0.5 mL 5.5 × 10¹² candida albicans suspension. On day 10, microscopic and histopathological examination were performed on stomach tissue of mice. Positive fungi under microscopy were all cultivated with CHROMagar, and observed.

RESULTS: Monilia sporus, blastospore, pseudohypha and a bulk of hypha in stomach were observed in model group. The differences in positive rates upon microscopic and histopathological examination between model group and control group Ⅰ were significant (χ² = 40.763, 40.526, both P < 0.01). There was also significant difference in positive rate between model group and control group Ⅱ (χ² = 58.964, 44.074, both P < 0.01).

CONCLUSION: By inhibiting immunity and inducing peptic ulcer, we can establish a mouse model of stomach with candida albicans infection.

Expression and changes of neuropeptide Y in the development of mouse stomach

AIM: To observe expression, distribution and development of neuropeptide Y in stomach of mouse embryo and to investigate relationship between the histological changes, functions and neuropeptide Y.

METHODS: HE staining and immunohistochemistry SABC method were used to study the expression of mouse stomach neuropeptide Y from embryonic day 13 (E13D) to day 21 (E21D).

RESULTS: Neuropeptide Y was positively expressed in embryonic muscle and epithelial mucosa with the successive growth in the mucosal plexus, muscular mucosa, submucosa, submucosal plexus in the fetal rat stomach at different development stages. Immune-response was increasingly strong with its peak value in E18D. There was a significant increase in the total number density of NPY in the stomach wall in E15D and significant differences were observed between E15D and E14D (2.26 ± 4.19 vs 1.05 ± 3.91, P < 0.05). The total area density was significantly increased in E18D, and significant difference was noted between E14-16D and E19D-21D (9.00 ± 3.41 vs 1.12 ± 1.10, 1.88 ± 4.75, 3.77 ± 5.09, 3.39 ± 3.11, 3.36 ± 4.11, 3.43 ± 3.16, P < 0.01); positive expression mucosa density was significantly higher in E18D than in the other groups (7.35 ± 5.01vs 2. 45 ± 2.79, 3. 41 ± 3.25, 5.89 ± 7.43, 3.55 ± 3.78, 4.33 ± 6.52, 3.21 ± 6.25, 2.77 ± 6.13, P < 0.05 or 0.01).

CONCLUSION: E14-E18D is a critical period in development of mice stomach. Neuropeptide Y is closely related to development of stomach.

Acute effects of Helicobacter pylori extracts on gastric mucosal blood flow in the mouse

AIM: To investigate the mechanisms underlying the reduction in gastric blood flow induced by a luminal water extract of Helicobacter pylori (HPE).

METHODS: The stomachs of isoflurane-anesthetized mice were exteriorized, and the mucosal surface exposed. Blood flow was measured with the laser-Doppler technique, and systemic arterial blood pressure monitored. C57BL/6 mice were exposed to water extract produced from H pylori strain 88-23. To investigate the role of a nerve- or iNOS-mediated pathway, we used intraluminal lidocaine and iNOS-/- mice. Blood flow response to the endogenous nitric oxide synthase inhibitor asymmetric dimethyl arginine (ADMA) was also assessed.

RESULTS: In wild-type mice, HPE decreased mucosal blood flow by approximately 30%. This reduction was abolished in iNOS-deficient mice, and by pre-treatment with lidocaine. Luminally applied ADMA resulted in reduction in blood flow similar to that observed in wild-type mice exposed to HPE.

CONCLUSION: A H pylori water extract reduces gastric mucosal blood flow acutely through iNOS- and nerve-mediated pathways.

Pre-ischemic Treatment with Ampicillin Reduces Neuronal Damage in the Mouse Hippocampus and Neostriatum after Transient Forebrain Ischemia

Ampicillin, a beta-lactam antibiotic, has been reported to induce astrocytic glutamate transporter-1 which plays a crucial role in protecting neurons against glutamate excitotoxicity. We investigated the effect of ampicillin on neuronal damage in the mouse hippocampus and neostriatum following transient global forebrain ischemia. Male C57BL/6 mice were anesthetized with halothane and subjected to bilateral occlusion of the common carotid artery for 40 min. Ampicillin was administered post-ischemically (for 3 days) and/or pre-ischemically (for 3~5 days until one day before the onset of ischemia). Pre- and post-ischemic treatment with ampicillin (50 mg/kg/day or 200 mg/kg/day) prevented ischemic neuronal death in the medial CA1 area of the hippocampus as well as the neostriatum in a dose-dependent manner. In addition, ischemic neuronal damage was reduced by pre-ischemic treatment with ampicillin (200 mg/kg/day). In summary, our results suggest that ampicillin plays a functional role as a chemical preconditioning agent that protects hippocampal neurons from ischemic insult.

Inhibitory effect of modified citrus pectin on liver metastases in a mouse colon cancer model

AIM: To discuss the expression of glactin-3 in liver metastasis of colon cancer and its inhibition by modified citrus pectin (MCP) in mice.

METHODS: Seventy-five Balb/c mice were randomly divided into negative control group (n = 15), positive control group (n = 15), low MCP concentration group (n = 15), middle MCP concentration group (n = 15) and high MCP concentration group (n = 15). CT26 colon cancer cells were injected into the subcapsule of mouse spleen in positive control group, low, middle and high MCP concentrations groups, except in negative control, to set up a colon cancer liver metastasis model. The concentration of MCP in drinking water was 0.0%, 0.0%, 1.0%, 2.5% and 5.0% (wt/vol), respectively. Liver metastasis of colon cancer was observed after 3 wk. Enzyme-linked immunosorbent assay (ELISA) was used to detect the concentration of galectin-3 in serum. Expression of galectin-3 in liver metastasis was detected by immunohistochemistry.

RESULTS: Except for the negative group, the percentage of liver metastasis in the other 4 groups was 100%, 80%, 73.3% and 60%, respectively. The number of liver metastases in high MCP concentration group was significantly less than that in positive control group (P = 0.008). Except for the negative group, the median volume of implanted spleen tumor in the other 4 groups was 1.51 cm³, 0.93 cm³, 0.77 cm³ and 0.70 cm³, respectively. The volume of implanted tumor in middle and high MCP concentration groups was significantly smaller than that in positive control group (P = 0.019; P = 0.003). The concentration of serum galectin-3 in positive control and MCP treatment groups was significantly higher than that in the negative control group. However, there was no significant difference between them. Except for the negative control group, the expression of galectin-3 in liver metastases of the other 4 groups showed no significant difference.

CONCLUSION: Expression of galectin-3 increases significantly in liver metastasis of colon cancer, which can be effectively inhibited by MCP.

Immunolocalization of nestin in pancreatic tissue of mice at different ages

AIM: To localize nestin positive cells (NPC) in pancreatic tissue of mice of different ages.

METHODS: Paraffin sections of 6-8 μm of fixed pancreatic samples were mounted on poly-L-lysine coated slides and used for Immunolocalization using appropriate primary antibodies (Nestin, Insulin, Glucagon), followed by addition of a fluorescently labeled secondary antibody. The antigen-antibody localization was captured using a confocal microscope (Leica SP 5 series).

RESULTS: In 3-6 d pups, the NPC were localized towards the periphery of the endocrine portion, as evident from immunolocalization of insulin and glucagon, while NPC were absent in the acinar portion. At 2 wk, NPC were localized in both the exocrine and endocrine portions. Interestingly, in 4-wk-old mice NPC were seen only in the endocrine portion, towards the periphery, and were colocalized with the glucagon positive cells. In the pancreas of 8- wk-old mice, the NPC were predominantly localized in the central region of the islet clusters, where immunostaining for insulin was at a maximum.

CONCLUSION: We report for the first time the immunolocalization of NPC in the pancreas of mice of different ages (3 d to 8 wk) with reference to insulin and glucagon positive cells. The heterogeneous localization of the NPC observed may be of functional and developmental significance and suggest(s) that mice pancreatic tissue can be a potential source of progenitor cells. NPC from the pancreas can be isolated, proliferated and programmed to differentiate into insulin secreting cells under the appropriate microenvironment.

Aflatoxin-mediated Sperm and Blood Cell Abnormalities in Mice Fed with Contaminated Corn

The effect of aflatoxin-contaminated corn on albino mice was investigated using the sperm morphology assay. Blood parameter levels including; total white blood cells (WBC), total red blood cells (RBC), packed cell volume (PCV), serum bilirubin (SB) and fasting blood sugar (FBS) were also determined in the tested mice. Test mice were exposed to aflatoxin-contaminated corn (contamination level of 100 ppb) for 1~4 weeks while aflatoxin-free corn and cyclophosphamide were used as negative and positive controls, respectively. Sperm cells showed varieties of morphological abnormality when assessed after 5 weeks. The percentage frequencies of the negative and positive controls were 18.8% and 48.87%, respectively, while the percentage abnormalities for the 1, 2, 3 and 4 weeks exposures were 41.38%, 48.17%, 57.13% and 61.67%, respectively. PCV, WBC, total bilirubin and glucose level values of mice in all concentrations were higher and statistically significant as compared to the negative control values using Dunnett's test. Therefore, abnormal sperm cell induction is concentration-dependent such that continuous consumption of aflatoxin-contaminated corn is capable of negatively affecting spermatogenesis by inducing or increasing the frequency of morphologically abnormal sperm cells produced.

Micronucleus Test of Kong-Jin-Dan, a Polyherbal Formula, in Bone Marrow Cells of Male ICR Mice

In this research, the genotoxic effects of Kong-Jin-Dan (KJD), a polyherbal formula were evaluated using the mouse micronucleus test. KJD was administered once a day for 2 continuous days by oral gavage to male ICR mice at doses of 2000, 1000 and 500 mg/kg. Cyclophosphamide was used as a known genotoxic agent in a positive control. The appearance of a micronucleus is used as an index for genotoxic potential. In addition, the changes on the total white blood cells and differential counts on the lymphocytes, neutrophils, eosinophils, basophils and monocytes in the prepared blood smears were also conducted to observe the possible immunosuppress. The results obtained indicated that KJD shows no genotoxicity effects up to 2000 mg/kg dosing levels, but KJD shows slight increased trends in the blood total leukocyte numbers as pharmacological effects of immune stimulation. In addition, it is also considered that there were no problems from cytotoxicity of KJD tested in this study because the polychromatic erythrocyte ratio was detected as > 0.42 in all tested groups.

Effect of dietary protein level and origin on the redox status in the digestive tract of mice

The present study was undertaken to evaluate the effects of high protein (soybean protein or casein) on the balance between production of free radicals and antioxidant level in digestive organs of mice. For this purpose, male (C57BL/6J) mice were adapted to experimental diets containing soybean protein or casein with 20% (normal protein diets, NPDs) or 60% (high protein diets, HPDs), and HPDs supplemented with 0.06g/kg cysteamine. After two weeks of feeding, oxidative and antioxidative parameters in duodenum, liver and pancreas were measured. The results show that ingestion of high protein markedly increased contents of superoxide anion and malondialdehyde (MDA), decreased activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT) and Na⁺ K⁺-ATPase, and content of reduced glutathione (GSH) in digestive organs of mice (P<0.05). Levels of oxidative parameters were lower and antioxidant capacity of both enzyme and non-enzyme was higher in mice fed with soybean protein than those fed with casein. In groups fed HPDs supplemented with cysteamine, oxidative stress was mitigated. However, oxidative parameter levels were still higher than those of NPD-fed groups. The present study indicates that ingestion of high protein diets could result in an imbalance between oxidant and antioxidant, and thus induce oxidative stress in digestive organs of mice. The oxidative damage was smaller in mice fed with high level of soy protein in comparison with casein.

Expression of NF-κB and its regulation products in experimental autoimmune hepatitis and its significance

AIM: To investigate the expression of nuclear factor kappa B (NF-κB), intercellular adhesion molecule-1 (ICAM-1), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in experimental autoimmune hepatitis (EAH) model and to explore the role of those molecules in liver injury of EAH.

METHODS: EAH model was induced by intra-peritoneal injection of syngeneic S-100 antigen emulsified in complete Freud's adjuvant into C57BL/6 on days 1, 7, 14 and 21. On the 28 day, animals were killed. Expressions of NF-κB, ICAM-1, TNF-α and IL-6 were observed using histoimmunochemistry

RESULTS: Liver cells in the control group were radially arranged from the central venous to the all sides. No inflammatory infiltration was observed in the portal area. Histology showed patchy necrosis of liver cells and lymphocyte infiltration in the EAH model. NF-κB, ICAM-1, TNF-α and IL-6 were not expressed in the control group but positively expressed in the model group.

CONCLUSION: NF-κB and its regulation products play an important role in the process of hepatic cell injury by regulating the expression of ICAM-1, TNF-α and IL-6.

Oral Single Dose Toxicity Study of Low Molecular Fucoidan in Mice

This study was conducted to obtain information of the oral dose toxicity of low molecular fucoidan (LMF) in male and female mice. In order to calculate 50% lethal dose (LD₅₀) and approximate lethal dose (LD), test material was once orally administered to male and female ICR mice at dose levels of 2000, 1000, 500, 250, 125 and 0 (vehicle control) mg/kg (body wt.). The mortality and the changes on body weight, clinical signs, gross observation and organ weight and histopathology of principle organs were monitored 14 days after LMF treatment. We could not find any mortalities, clinical signs, body weight changes and gross findings. In addition, significant changes in the organ weight and histopathology of principal organs were not observed except for some sporadic findings. The results obtained in this study suggest that LMF may not be toxic in mice and may be therefore safe for clinical use. The LD₅₀ and approximate LD in mice after single oral dose of LMF were considered over 2000 mg/kg in both female and male mice.

Micronucleus Test of Polycan™, β-Glucan Originated from Aureobasidium, in Bone Marrow Cells of Male ICR Mice

In this research the genotoxic effect of Polycan™ β-glucans originated from Aureobasidium pullulans SM-2001, was evaluated using the mouse micronucleus test. Polycan™ was administered once a day for 2 days by oral gavage to male ICR mice at doses of 1000, 500 and 250 mg/kg. Cyclophosphamide was used as a known genotoxic agent in a positive control group. The appearance of a micronucleus is used as an index for genotoxic potential. The results obtained indicated that Polycan™ shows no genotoxicity effect up to 1000 mg/kg dosing levels. In addition, it is also considered that there were no problems from cytotoxicity of Polycan™ tested in this study because the polychromatic erythrocyte ratio was detected as > 0.47 in all tested groups.

Experimental study of herbal-based medicine Hong Tian Gan Kang on the intervention and therapy for hepatic cirrhosis

AIM: To investigate the prevention and treatment of Hong Tian Gan Kang (HTGK) on experimental hepatic cirrhosis.

METHODS: The female ICR mice were allocated into traditional Chinese medicine (HTGK) prevention group, treatment group, animal model group, and control group. During the process of inducing hepatocirrhosis by CCl4 celiac injection in ICR mice, the HTGK group received HTGK per day, while the model group was created into the animal model by the above means without treatment. The mice of control group were normally raised without being created into models. The control group, animal model group and (HTGK) prevention group were sacrificed randomly at the end of the 60 d, 90 d and 180 d; while treatment group was sacrificed randomly at the end of the 30 d, 60 d and 90 d. Tissue specimens were taken. Animals received liver histopathology and ultrastructure test.

RESULTS: Up to day 180, marked hepatic fatty changes, inflammation, necrosis and fibrosis were observed in mice of model group. In contrast, these alternations were attenuated by HTGK administration although mild fatty changes remained. Compared with the CCl4-induced cirrhotic mice, histological changes of fibrosis were improved significantly in the mice treated with HTGK. Liver histopathology showed that the contents of transforming growth factor-β1 (TGF-β1) and alpha-smooth muscle actin (α-SMA) in the animal model group were significantly higher than those in the control group (TGF-β1, 60 d: 0.269 vs 0.155; 90 d: 0.306 vs 0.155; 180 d: 0.336 vs 0.160; α-SMA, 60 d: 0.269 vs 0.160; 90 d: 0.299 vs 0.150; 180 d: 0.322 vs 0.155, P < 0.01). However, the contents of TGF-β1 and α-SMA in the therapy group were significantly lower than those in the model group (0.220, 0.203, 0.185 vs 0.336, P < 0.01; 0.2451, 0.2113, 0.185 vs 0.3217, P < 0.01).

CONCLUSION: HTGK has suppressive, preventive and curative effect on hepatic fibrosis and hepatocirrhosis.

QRS voltages are transiently increased at the superacute stage of experimental myocarditis

BACKGROUND

There are few reports on the precise electrocardiographic characteristics of acute myocarditis. The present study was focused on QRS voltage changes at the superacute stage of murine myocarditis.

METHODS

Serial electrocardiograms were recorded during the acute stage of viral myocarditis in mice, and then the cardiac pathology was examined. After recording baseline electrocardiograms, mice (n=235) were inoculated intraperitoneally with the encephalomyocarditis virus, resulting in severe myocarditis. Electrocardiograms were serially recorded until nine days after virus inoculation (superacute stage, days 3 to 6; acute stage, days 7 to 9). Changes in heart rate and QRS voltages were analyzed.

RESULTS

Serial electrocardiograms revealed that heart rates began to increase after day 3, and that the sum of the QRS voltages increased on day 3 and then decreased on days 7 to 9. Trivial mononuclear cell infiltrations and interstitial edema were most frequently found in mice at the superacute stage.

CONCLUSIONS

Transient increase of the QRS voltages at the superacute stage of myocarditis was demonstrated, which may be due to an increase in ventricular mass caused by interstitial edema at this stage.

Therapeutic effects of elemene and chemotherapy in tumor-bearing mice

AIM: To explore a potential treatment for carcinoma by observing the therapeutic effects of elemene and chemotherapy in tumor-bearing mice (LT).

METHODS: Pharmaceuticals were injected into the centers of tumors in tumor-bearing mice, and the expression of the multidrug resistance gene (mdr1) was determined by reverse transcription-polymerase chain reaction. The rate of inhibition of tumor growth, the pathology of the tumor and mortality were noted.

RESULTS: The expression levels of mdr1 in chemotherapy (C), elemene (E) and chemiotherapy+elemene (CE) groups were 100%, 16.67% and 8.33% of the levels in the tumor-bearing (LT) group, respectively, and there was statistical significance between the E (or CE) and LT groups (P < 0.05). The rates of inhibition of tumor growth in mice in groups C, E and CE were 24.3%, 29.7%, and 39.5%, respectively, and there was statistical significance when compared with LT mice, P < 0.05. The mortality of mice in groups C, E and CE was 20%, 10%, and 10%, respectively, and there was statistical significance when compared with LT mice (40%) (P < 0.05). Tumor necrosis was outstanding in CE mice, and these mice were more energetic than the mice in other groups.

CONCLUSION: Elemene can reduce the expression of the mdr1 gene and is effective in killing tumors. Further, it is more effective when combined with a chemotherapeutic agent.

Hypoestoxide inhibits tumor growth in the mouse CT26 colon tumor model

AIM: To evaluate the effect of the natural diterpenoid, hypoestoxide (HE) on the growth of established colon cancer in mice.

METHODS: The CT26.WT mouse colon carcinoma cell line was grown and expanded in vitro. Following the expansion, BALB/c mice were inoculated s.c. with viable tumor cells. After the tumors had established and developed to about 80-90 mm³, the mice were started on chemotherapy by oral administration of HE, 5-fluorouracil (5-FU) or combination.

RESULTS: The antiangiogenic HE has previously been shown to inhibit the growth of melanoma in the B16F₁ tumor model in C57BL/6 mice. Our results demonstrate that mean volume of tumors in mice treated with oral HE as a single agent or in combination with 5-FU, were significantly smaller (> 60%) than those in vehicle control mice (471.2 mm³vs 1542.8 mm³, P < 0.01). The significant reductions in tumor burden resulted in pronounced mean survival times (MST) and increased life spans (ILS) in the treated mice.

CONCLUSION: These results indicate that HE is an effective chemotherapeutic agent for colorectal cancer in mice and that HE may be used alone or in combination with 5-FU.

Gene expression profile analyses of mice livers injured by Leigongteng

AIM: To analyze the gene expression profiles of mice livers injured by Leigongteng and explore the relationship between the differentially expressed genes and liver damage.

METHODS: The experimental mice were randomly divided into a control group and a liver-injured group in which the mice were administrated 33 μγ of triptolide/kg per day for 30 d. Liver mRNAs were extracted from animals in both groups and were reverse-transcribed to cDNA with dUTP labeled by different fluorescence (Cy3, Cy5) as hybridization probes. The mixed probes were hybridized with oligonucleotide microarray chips. The fluorescent signal results were acquired by scanner and analyzed with software.

RESULTS: Among the 35852 target genes, 29 genes were found to be significantly differentially expressed, with 20 genes up-regulated and 9 genes down-regulated. The reliability of the differentially expressed genes was validated by RT-PCR experiments of 5 randomly selected differentially expressed genes.

CONCLUSION: Based on the biological functions of the differentially expressed genes, it is obvious that the occurrence and development of liver damage induced by Leigongteng in mice are highly associated with immune response, metabolism, apoptosis and the cell skeleton of liver cells. This might be important for elucidating the regulatory network of gene expression associated with liver damage and it may also be important for discovering the pathogenic mechanisms of liver damage induced by Leigongteng.

Evaluation of the effect of pyrrolidine dithiocarbamate in suppressing inflammation in mice with dextran sodium sulfate-induced colitis

AIM: To evaluate the effect of pyrrolidine dithio-carbamate (PDTC; an NF-κB inhibitor) administered at low (50 mg/kg) and high (100 mg/kg) doses in suppressing colitis in mice with dextran sodium sulfate (DSS)-induced colitis.

METHODS: Mice were divided into a DSS-untreated group (normal group), DSS-treated control group, DSS+PDTC-treated groupI(low-dose group), and DSS+PDTC-treated groupII (high-dose group). In each group, the disease activity index score (DAI score), intestinal length, histological score, and the levels of activated NF-κB and inflammatory cytokines (IL-1β and TNF-α) in tissue were measured.

RESULTS: The DSS+PDTC-treated groupII exhibited suppression of shortening of intestinal length and reduction of DAI score. Activated NF-κB level and IL-1β and TNF-α levels were significantly lower in DSS+PDTC-treated groupII.

CONCLUSION: These findings suggest that PDTC is useful for the treatment of ulcerative colitis.

Down-regulated expression of intestinal epithelial tight junction protein occludin in mice with fulminant hepatic failure

AIM: To observe the changes of intestinal epithelial tight junction protein occludin in mice with fulminant hepatic failure (FHF), and explore the mechanisms of spontaneous bacterial peritonitis (SBP).

METHODS: A total of 150 male BALB/c mice were divided into group A, B, C and D. The mice in group D were intraperitoneally injected with lipopolysaccharide (LPS, 10 μg/kg) and D-galactosamine (GalN, 800 mg/kg) to induce the model of FHF, while the mice in group A, B and C were intraperitioncally injected normal saline, LPS, and GalN, respectively. At the end of the 2^nd, 6^th, and 9^th h, the mice were killed for the collection of liver and intestinal specimens. Immunohistochemistry, Western blot and quantitative real time polymerase chain reaction (QRT-PCR) were used to detect the distribution and expression of intestinal epithelial tight junction protein occludin.

RESULTS: Tight junction protein occludin was localized along the apical region of the lateral plasma membrane representing the region of tight junctions in surface and crypt epithelial cells. In mucosal tissues from mice with FHF 6 and 9 h after injection, occludin-positive staining was gradually weakened. Western blot demonstrated consistent and significant reduction of occludin expression in mice with FHF at the 6^th (0.48 ± 0.07) and 9^th h (0.36 ± 0.05) (P < 0.05), which was significantly lower than that in group A (0.71 ± 0.09) (P < 0.05). Furthermore, the expression of occludin mRNA was decreased starting from the 2^nd h (0.85 ± 0.12), and reached the lowest level at 6^th h (0.72 ± 0.04), significantly lower than that in group A. At the 9^th h, occludin mRNA expression almost restored (0.93 ± 0.10) to the normal level.

CONCLUSION: The expression of tight junction protein occludin is decreased at both protein and mRNA level in intestinal epithelial cells of mice with FHF.

Preventive effect of a pectic polysaccharide of the common cranberry Vaccinium oxycoccos L. on acetic acid-induced colitis in mice

AIM: To study isolation and chemical characterization of pectin derived from the common cranberry Vaccinium oxycoccos L. (oxycoccusan OP) and the testing of its preventive effect on experimental colitis.

METHODS: Mice were administrated orally with OP two days prior to a rectal injection of 5% acetic acid and examined for colonic damage 24 h later. Colonic inflammation was characterized by macroscopical injury and enhanced levels of myeloperoxidase activity measured spectrophotometrically with o-phenylene diamine as the substrate. The mucus contents of the colon were determined by the Alcian blue dye binding method. Vascular permeability was estimated using 4% Evans blue passage after i.p. injection of 0.05 mol/L acetic acid.

RESULTS: In the mice treated with OP, colonic macroscopic scores (1.1 ± 0.4 vs 2.7, P < 0.01) and the total square area of damage (10 ± 2 vs 21 ± 7, P < 0.01) were significantly reduced when compared with the vehicle-treated colitis group. OP was shown to decrease the tissue myeloperoxidase activity in colons (42 ± 11 vs 112 ± 40, P < 0.01) and enhance the amount of mucus of colitis mice (0.9 ± 0.1 vs 0.4 ± 0.1, P < 0.01). The level of colonic malondialdehyde was noted to decrease in OP-pretreated mice (3.6 ± 0.7 vs 5.1 ± 0.8, P < 0.01). OP was found to decrease the inflammatory status of mice as was determined by reduction of vascular permeability (161 ± 34 vs 241 ± 21, P < 0.01). Adhesion of peritoneal neutrophils and macrophages was also shown to decrease after administration of OP (141 ± 50 vs 235 ± 37, P < 0.05).

CONCLUSION: Thus, a preventive effect of pectin from the common cranberry, namely oxycoccusan OP, on acetic acid-induced colitis in mice was detected. A reduction of neutrophil infiltration and antioxidant action may be implicated in the protective effect of oxycoccusan.

Influence factors of post-immunization gastritis after Helicobacter pylori vaccine immunization in mice

AIM: To explore the influence factors of post-immunization gastritis after H. pylori vaccine immunization in mice.

METHODS: (1) C₅₇BL/6 and BALB/c mice were orally immunized with H. pylori vaccine (H. pylori whole cell sonicate antigen plus mucosa adjuvant cholera toxin). Gastric H. pylori infection and inflammation were evaluated after H. pylori challenge. (2) C₅₇BL/6 mice were orally immunized with H. pylori vaccine, and then challenged by different amounts of H. pylori. Gastric H. pylori infection and inflammation were evaluated after H. pylori challenge. (3) C₅₇BL/6 mice were immunized orally or intraperitoneally with H. pylori vaccine. Gastric H. pylori infection and inflammation were evaluated after H. pylori challenge at different time points. (4) Infected C₅₇BL/6 mice were orally immunized with H. pylori vaccine, and gastric H. pylori infection and inflammation were evaluated after immunization at different time points.

RESULTS: (1) Similar decreasing of H. pylori colonization was found in both C₅₇BL/6 and BALB/c mice. However, C₅₇BL/6 mice showed more severe post-immunization gastritis than BALB/c mice did. (2) Although H. pylori colonization was similar in all groups with different challenging amounts, larger amount of H. pylori challenge induced more severe post-immunization gastritis. (3) Similar post-immunization gastritis and decreasing of H. pylori colonization were found in mice with both oral and intraperitoneal immunization at different time points. (4) Therapeutic immunization led to significant decreasing of H. pylori colonization in infected mice; meanwhile more severe gastritis was also found in therapeutic group when compared with that in control group.

CONCLUSION: Post-immunization gastritis occurs in different immune hosts, the same hosts with different vaccination routes and hosts received therapeutic immunization. H. pylori challenge amounts and immune host are influential factors of post-immunization gastritis degree.

Expression of recombination human anti-HBsAg Fab in murine liver

AIM: To evaluate the expression of recombinant and soluble human anti-HBsAg Fab in murine liver.

METHODS: The 5-40 μg recombinant plasmid pXXUF1-HBs-Fab was transfected by hydrodynamics-based administration via tail vein into C57BL/6 mice within 5 s. Meanwhile the empty plasmid transfection group and non-transfection group were established. The serum and tissue samples from liver, kidney and spleen of these mice were collected 3 d after transfection. The expression of genetically engineered Fab antibody in vivo was identified by reverse transcription-polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry both at mRNA and protein level.

RESULTS: After transfection with different doses (5, 10, 20 and 40 μg) of pXXUF1-HBs-Fab, the plasma expression of anti-HBsAg Fab was 201.3 ± 13.7, 213.1 ± 13.5, 513.6 ± 12.8 and 954.1 ± 12.7 μg/L, respectively, with specific binding activities to HBsAg protein. There was a postive correlation between the expression of the protein and plasmid dose(r = 0.912, P < 0.01). Meanwhile, the mRNA of Fd and κ chain were detected in liver tissues by RT-PCR. Immunohistochemistry showed brown positive granules in the cytoplasm of liver cells and Fab protein cohered on the inner walls of glomerular capillary lumen and collectors, but the parenchyma cells of the kidney and spleen had no expression of Fd, κ chain and the target protein. The expression of target protein was not observed in both empty plasmid transfection and non-transfection group.

CONCLUSION: The recombinant and soluble human anti-HBsAg Fab can be successfully expressed in mice, and the expression level is increased with the increase of plasmid dose. The above study also shows the Fab protein can be filtrated through glomerular.

Expression of Cyclin D1, proliferating cell nuclear antigen in liver of C57BL/6 mice infected with Helicobacter pylori

AIM: To detect the expression of Cyclin D1 and proliferating cell nuclear antigen (PCNA) in liver tissues of C57BL/6 mice infected with H. pylori by oral inoculation.

METHODS: Thirty C57BL/6 strain mice, used as experiment animal, were orally inoculated with H. pylori SS1 strain and fed in laminar flow cabinets for 8 mo. H. pylori 16S rRNA in liver was examined by nested polymerase chain reaction (PCR), and then mRNA and protein were extracted from the positive liver tissues. The mRNA and protein expression of Cyclin D1 and PCNA were detected by reverse transcription PCR (RT-PCR) and Western blot, respectively.

RESULTS: Six of fifteen liver tissues were positive for H. pylori 16S rRNA after examination of nested PCR. Sequencing results of 16S rRNA PCR products showed the 100% homogeneity with cultured H. pylori from gastric mucosa and inoculated H. pylori SS1. The mRNA expression of Cyclin D1 and PCNA in liver of C57BL/6 mice infected with H. pylori were significantly increased in comparison with those in the controls (0.78 ± 0.13 vs 0.66 ± 0.03, P < 0.05; 0.86 ± 0.17 vs 0.56 ± 0.24, P < 0.01), and the protein expression of PCNA was also increased (1.16 ± 0.40 vs 0.64 ± 0.11, P < 0.05). Although the expression of Cyclin D1 protein had an increased tendency, it was not significantly different from those in the controls (P > 0.05).

CONCLUSION: H. pylori inoculated orally can arrive at liver, and induce increased expression of Cyclin D1 and PCNA.

Effect of a new opioid peptide on opioid receptor and peptide transporter gene of brain and small intestinal tissues in mice

AIM: To investigate the effect of a new opioid peptide, YPFPGPIRYG, on the opioid receptor and peptide transporter gene of brain and small intestinal tissues via gastrointestinal tracts at transcription level.

METHODS: Twenty-four mice were randomly divided into opioid group (n = 12) and control group (n = 12), which were fed with 8×10^-7 mol/L YPFPGPIRYG and double distilled water, respectively, for 2 wk. The total RNA was extracted from the brain and small intestinal tissues of mice for the detection of μ-, δ-opioid receptor and peptide transporters PepT1 gene expression by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS: In the brain and small intestinal tissues, μ- and δ-opioid receptor transcripts were detected, while peptide transporter PepT1 was only found to be expressed in the small intestine. In comparison with those in the controls, the expression of μ- and δ-opioid receptor were significantly enhanced in the small intestine (P < 0.05), but not in the brain, and PepT1 gene expression was not changed in the intestinal tissues of mice treated with YPFPGPIRYG.

CONCLUSION: Opioid receptor expression has tissue specificity. The immunomodulatory effects of opioid YPFPGPIRYG do not attribute to the interaction with the opioid receptors in central nervous system (CNS), but with d- and m-opioid receptor in small intestine.

Gene cloning and expression identification of murine a-fetoprotein gene and establishment of a cell line stably expressing a-fetoprotein

AIM: To clone the murine a-fetoprotein (mAFP) gene, construct the eukaryotic expression vector of AFP and establish a cell line stably expressing AFP.

METHODS: The total RNA was extracted from Hepa1-6 cells. The mAFP gene was amplified by reverse transcription polymerase chain reaction (RT-PCR) and cloned into the eukaryotic expression vector pcDNA3.1 to construct pmAFP. The pmAFP was identified by restriction enzyme analysis and sequencing, and then stably transfected into EL-4 cell line. Western blot and RT-PCR were used to detect the expression of mAFP protein and mRNA, respectively. EL-4 cells stably expressing mAFP were inoculated in the back of 6 mice to observe the tumor formation.

RESULTS: The mAFP gene with a length of 1.8 kb was successfully cloned from the total RNA of Hepa1-6 cells. Restriction enzyme analysis and sequencing showed that the 1.8 kb mAFP gene was successfully cloned and inserted into pcDNA3.1. RT-PCR and Western blot showed mAFP was stably expressed in EL-4 cell line. The tumor grew to a volume of 2 279.97 ± 235.13 mm³ 22 d after inoculation in 5 mice.

CONCLUSION: The mAFP gene is successfully cloned and a cell line stably expressing mAFP, named EL-4 (mAFP), is established. EL-4 (mAFP) has a good tumor-forming capacity in mice.

Serum interleukin-1 receptor antagonist is an early indicator of colitis onset in Gαi2-deficient mice

AIM: To study the serum concentration of IL-1β, IL-1 receptor antagonist (IL-1Ra) and IL-18 in Gαi2-deficient mice at the age of 6 (healthy), 12 (pre-colitic) and 24 wk (colitic) and in healthy control mice.

METHODS: At the time of killing, serum samples were collected and IL-1β, IL-1Ra and IL-18 levels were measured using enzyme-linked immunosorbent assays.

RESULTS: Serum concentration of IL-1Ra was significantly increased in pre-colitic (median: 524 ng/L; P = 0.02) and colitic (450 ng/L; P  = 0.01), but not in healthy (196 ng/L) Gαi2-deficient mice as compared with controls (217 ng/L). Serum concentrations of IL-1β did not differ between Gαi2-deficient mice and their controls, irrespective of age, IL-18 was significantly increased in colitic, but not in pre-colitic mice compared with controls (510 ng/L vs 190 ng/L; P  = 0.05).

CONCLUSION: The increased serum concentrations of IL-18 and IL-1Ra in established diseases are suggested as markers of ongoing colitis. Interestingly, the significantly increased serum concentration of IL-1Ra in pre-colitic mice is found to be an early marker of disease progression.

Activity of cytokines in dinitrochlorobenzene-induced colitis in mice

AIM: To observe the changes of serum pro-inflammatory and anti-inflammatory cytokine activities in mice with experimental colitis.

METHODS: A total of 33 BALB/c mice were randomly divided into control (n = 15) and experiment group(n = 18). After sensitized by 2, 4-dinitrochlorobenzene (DNCB) smeared on the abdominal skin, the mice in the experiment group were challenged with DNCB enema, while those in the control group were treated with ethanol. The body weight, stool viscosity and hematochezia were observed and accumulated as disease active index (DAI) score; the colon pathological score was achieved by macropathology and HE staining of section prepared for microscopy. The activity of serum IL-1, TNFa, IL-6, IL-4 and IL-10 was determined.

RESULTS: The percentage of diarrhea was 59% in the experiment mice 24 h after DNCB treatment, and serious weight loss was found, 20% mice died. Pathologically, the mice in the control group had normal histological structures and glands, and no ulcer was found except for occasional light mucosal congestion. However, the decrease in the number of glands and disturbance of tissue structure were observed in the mice of experiment group. Moreover, erosion, hemorrhage, necrosis as well as deeper ulcers were easily seen. As compared with those in the control mice, the DAI (3.82 ± 2.77 vs 1.25 ± 1.65, P <0.05), pathologic score (2.47 ± 1.33 vs 0.38 ± 0.72, P <0.05) were significantly increased in the experiment mice. The activities of pro-inflammatory cytokines such as IL-1(112.9 ± 8.3 ng/L vs 81.2 ± 16.3 ng/L, P <0.01), TNF-a(137.9 ±36.7 ng/L vs 110.3 ± 22.4 ng/L, P <0.05), and IL-6(48.2 ± 4.3 ng/L vs 36.1 ± 7.2 ng/L, P <0.01) were significantly increased, while the activities of anti-inflammatory cytokines such as IL-4 (96.7 ± 16.5 ng/L vs 130.1 ± 13.1 ng/L, P <0.01) and IL-10(107.3 ± 31.2 ng/L vs 149.8 ± 45.1 ng/L, P <0.01) were markedly lowered.

CONCLUSION: The pathological progress of colitis induced by DNCB is possiblely related with the increased activities of pro-inflammatory cytokines and decreased activities of anti-inflammatory cytokines.

Experimental research on treatment of ulcerative colitis with integrative traditional Chinese and Western medicine

AIM: To explore the effect of the clyster treatment with integrated traditional Chinese and Western medicine on ulcerative colitis (UC), and to investigate its mechanism.

METHODS: The mouse model of UC was established, and then the rats were treated (clyster) with the combination of tin-like powder, dexamethasone, gentamicin, and berberine. Then the therapeutic effect was observed, and the mechanism of the treatment was analyzed.

RESULTS: The disease active index (DAI) and histopathologic score (HPS) of the low dose (DAI: 5.10±4.07, HPS: 8.00±6.38), the moderate dose (DAI: 0.80±1.87, HPS: 1.30±1.49), the high dose (DAI: 1.00±1.94, HPS: 0.90±1.45), and the positive control group (DAI: 5.30±4.37, HPS: 8.00±5.12) were markedly lower than those of the negative control group (DAI: 8.60±1.26, HPS: 13.20±1.69) (all P <0.05). The DAI and HPS of the moderate dose group were markedly lower than those of the low dose group and the positive control group (all P <0.05), but there was no significant difference between the moderate and high dose group (P >0.05). The levels of interleukin-4 (IL-4) of the low, moderate, and high dose group, and the positive control group were markedly lower than those of the negative control group (32.33±15.30, 25.79±6.33, 29.92±12.81, 28.45±9.30 vs 63.89±11.31, all P <0.05), but the levels of interferon-γ (IFN-γ) were markedly higher than those of the negative control group (198.38±31.46, 187.49±13.04, 188.14±14.11, 207.64±41.44 vs 127.41±21.47, all P <0.05).

CONCLUSION: The combination enema of tin-like powder, dexamethasone, gentamicin, and berberine has definite therapeutic effect on UC, which may be related with its regulation on IL-4 and IFN-γ level.

Inhibitory effect of arsenic trioxide on proliferation of hepatoma cells in mice

AIM: To explore the arsenic trioxide(As₂O₃)-induced inhibition of the proliferation of mouse hepatoma cells in vivo.

METHODS: The mice bearing H₂₂ solid and ascetic hepatoma cells were treated with different concentrations of arsenic trioxide. The growth of the solid tumor and the survival of the ascetic tumor-bearing mice were observed. The expression of proliferating cell nuclear antigen (PCNA) and cyclinD₁ of the tumor cells were examined by immunohistochemical methods. The changes of cell cycle were measured by flow cytometry. The ultra-structural changes of the cells were observed under electron microscope.

RESULTS: Both high and low concentration of As₂O₃ inhibited the growth of the solid tumor and prolonged the survival time of ascetic-tumor-bearing mice, and the inhibitory rates were 39.1% and 45.7%, respectively. The life prolonging rates were 57.2% and 97.7%, respectively. The positive rates of PCNA and cyclinD₁ expression in the As₂O₃-treated groups were significantly decreased from 57.9±6.6% to 44.0±5.0% (P <0.01), and from 49.2±9.3% to 37.6±6.3% (P <0.01), respectively. Flow cytometry showed that the percentage of G₀/G₁ phase cells was decreased and the percentage of G₂/M phase cells was increased. Electron microscopy showed the typical characteristics of cell apoptosis.

CONCLUSION: As₂O₃ can significantly inhibit the proliferation of mouse hepatoma cells.

Expression of ether-a-go-go-related gene in gastrointestinal tract of normal CD1 mice

AIM: To investigate the expression of ether-a-go-go-related gene (ERG) mRNA and protein and its different distributions in the gastrointestinal tract of CD1 mice.

METHODS: The expression of ERG K+ current related protein was examined by immunohistochemistry and the expression of ERG mRNA was detected by reverse transcription polymerase chain reaction (RT-PCR) and in situ hybridization in the tissues of stomach, jejunum, ileum and colon from adult CD1 mice. Then the distribution of ERG was analyzed.

RESULTS: ERG was positively expressed in all the tissues of stomach, jejunum, ileum and colon. The positive cells mainly distributed in the muscular layer. A small number of positive cells distributed in the mucosa and chorion. The levels of ERG expression in stomach and colon were significantly higher than those in jejunum and ileum (4.30±0.95, 3.60±0.70 vs2.70±0.82, 2.30±1.06; P<0.05).

CONCLUSION: ERG is expressed in the gastrointestinal tract of CD1 mice. Furthermore, the expression is differential at different sites.

Comparison of murine cirrhosis models induced by hepatotoxin administration and common bile duct ligation

AIM: To build up the research models of hepatic fibrosis in mice.

METHODS: Inbred wild-type FVB/N mice were either treated with alpha-naphthyl-isothiocyanate (ANIT), allyl alcohol (AA), carbon tetrachloride (CCl₄), 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC), and silica, or subjected to common bile duct ligation (CBDL) to induce hepatic injury. Liver biopsies were performed every 4 wk to evaluate hepatic fibrosis over a period of 6 mo. Cumulative cirrhosis and survival curves were constructed by life table method and compared with Wilcoxon test.

RESULTS: Under the dosages used, there was neither mortality nor cirrhosis in AA and silica-treated groups. DDC and ANIT caused cirrhosis within 4-12 and 12-24 wk, respectively. Both showed significantly faster cirrhosis induction at high dosages without significant alteration of survival. The duration for cirrhosis induction by CCl₄ ranged from 4 to 20 wk, mainly dependent upon the dosage. However, the increase in CCl₄ dosage significantly worsened survival. Intraperitoneal CCl₄ administration resulted in better survival in comparison with gavage administration at high dosage, but not at medium and low dosages. After CBDL, all the mice developed liver cirrhosis within 4-8 wk and then died by the end of 16 wk.

CONCLUSION: CBDL and administrations of ANIT, CCl₄, and DDC ensured liver cirrhosis. CBDL required the least amount of time in cirrhosis induction, but caused shortened lives of mice. It was followed by DDC and ANIT administration with favorable survival. As for CCl₄, the speed of cirrhosis induction and the mouse survival depended upon the dosages and the administration route.

Immunization of mice with concentrated liquor from male zooid of Antheraea pernyi

AIM: To study the effects of concentrated liquor from male zooid of Antheraea pernyi on immunological mice.

METHODS: For each experiment, 40 mice were randomly divided into normal saline group (control group) and three tested groups that were administered different dosages of concentrated liquor from male zooid of A. pernyi and food for 15 d. The typical FSR and HC₅₀ value, monocyte-phagocytic exponent K and emendated monocyte-phagocytic exponent α were determined and calculated respectively.

RESULTS: After 24 and 48 h, the FSR values of the three tested groups improved significantly in comparison to the control group by variance analysis. The HC₅₀ values showed a significant difference between the high dosage group and the control group, as well as between the high dosage group and other two tested groups. The monocyte-phagocytic exponent K and emendated exponent α showed rising tendencies, but no significant differences were found by variance analysis.

CONCLUSION: The concentrated liquor from male zooid of A. pernyi can significantly enhance cellular and humoral immune function in mice, but has no distinct influence on the monocyte-phagocytic system in mice.

Roles of Glutathione in dextran sodium sulphate-induced colitis in mice

AIM: To investigate the expression of glutathione (GSH) in dextran sodium sulphate(DSS)-induced colitic mucosa and its relationship with cytokine secretion as well as mucosal injury.

METHODS: BALB/c mice in DSS group (n = 10) were fed with 50 g/L DSS to induce experimental colitis and those in normal controls (n = 10) were fed with distilled water. All the mice were killed after 7 days. The pathological changes of the colonic tissues were examined while immunohi-stochemstry was performed with GSH1 antibody to determine the GSH expression. ELISA was used to detect the expression of IL-4 and IFN-γ.

RESULTS: The manifestations of acute colitis such as weight decrease, diarrhea and bloody stool appeared in mice of DSS group. focal crypt lesionsPathologically, focal crypt distortion, granulocyte and macrophage invasion were observed. The level of GSH in DSS group was significantly lower than that in control group (20.6 vs 3.14±1.0, t = 3.95, P = 0.01), whereas the expression of IL-4 was marked higher (38.7±4.7 vs 28.7±6.7, t = 3.16, P = 0.009). The content of IFN-γ was decreased in DSS group (P>0.05).

CONCLUSION: Low expression of GSH is related to the increase of IL-4, decrease of IFN-γ and mucosal injury in DSS-induced colitis in mice.

Protective effect of extraction from Hygrophila salicifolia on mice acute hepatic injury

AIM: To investigate the hepatoprotective effect of the extraction from Hygrophila salicifolia.

METHODS: Forty male Kunming mice were divided equally into the normal control group, the CCl₄ injury group, the low-dose (45 g/kg) Hygrophila salicifolia group, the high-dose (90 g/kg) Hygrophila salicifolia group, and the Bifendate (150 mg/kg) group. All the mice except for those in the normal control group had acute hepatic injury induced by carbon tetrachloride (CCl₄) 10 mL/kg injected intraperitoneally. The animals were killed 16 h after CCl₄ administration. The activities of serum ALT and AST, as well as the pathological changes of the liver were determined in all groups.

RESULTS: In comparison to the normal control group, the activities of serum ALT and AST in mice with CCl₄ injury were increased significantly (P<0.01). The liver histology showed mild to serious necrosis and degeneration. Serum ALT and AST in both Hygrophila salicifolia groups were significantly lower than those in CCl₄ injury group(ALT: 1 485±755, 1 211±528, 3 179±106; AST: 2 045±293, 2 052±386, 2 583±116, in low-dose, high-dose Hygrophila salicifolia, and CCl₄ injury group, respectively, all P<0.01). The liver necrosis and degeneration induced by CCl₄ were also improved significantly after Hygrophila salicifolia administration. The effect of high-dose Hygrophila salicifolia was superior to that of Bifendate.

CONCLUSION: The extraction from Hygrophila salicifolia can protect the liver from damage induced by CCl₄ in a dose-dependent manner. The effect of high-dose Hygrophila salicifolia is better than that of Bifendate.

CpG oligodeoxynucleotides inhibit tumor growth and reverse the immunosuppression caused by the therapy with 5-fluorouracil in murine hepatoma

AIM: To investigate the effect of CpG-containing oligodeoxynucleotides (CpG ODN) alone or in combination with the chemotherapeutic agent 5-fluorouracil (5-FU) on tumor growth and whether CpG ODN can reverse the immunosuppression caused by the chemotherapy with 5-FU in murine hepatoma model.

METHODS: Hepatoma model was established by subcutaneous inoculation with hepatoma-22 (H₂₂) cells into the right flank of BALB/c mice. Mice with tumor were treated by peritumoral injection of CpG ODN alone or in combination with subcutaneous injection of 5-FU. Tumor size was quantified regularly. Serum levels of IL-12 and IFN-γ in mice were assayed by enzyme-linked immunosorbent assay (ELISA). The lytic capacity of splenic NK cells was tested by lactate dehydrogenase release assay.

RESULTS: Peritumoral injection of CpG ODN alone or in combination with subcutaneous injection of 5-FU, and the treatment with 5-FU alone all led to significant inhibition of hepatoma growth. The mean tumor volumes fell by 46.66% in mice injected with CpG ODN, 68.34% in the 5-FU treated mice, and 70.23% in mice treated with the combination of CpG ODN and 5-FU than in controls. There was no significant difference in tumor size between 5-FU-treated mice and mice treated with the combination of 5-FU and CpG ODN (P>0.05). The serum levels of IL-12 and IFN-γ of mice treated with CpG ODN alone (IL-12: 464.50±24.37 pg/mL; IFN-γ: 134.20±25.76 pg/mL) or with the co-administration of CpG ODN and 5-FU (IL-12: 335.83±28.74 pg/mL; IFN-γ: 111.00±5.33 pg/mL) were significantly higher than that of controls (IL-12: 237.50±45.31 pg/mL; IFN-γ: 56.75±8.22 pg/mL). The production of IL-12 and IFN-γ was suppressed moderately in 5-FU-treated mice (IL-12: 166.67±53.22 pg/mL; 53.33±16.98 pg/mL) compared to control mice (P>0.05), whereas the combination of CpG ODN and 5-FU significantly increased the serum levels of IL-12 and IFN-γ compared to 5-FU alone (P<0.05). The NK cell killing activity in CpG ODN-treated mice (44.04±1.38%) or the mice treated with CpG ODN combined with 5-FU (30.67±1.28%) was significantly potentiated compared to controls (19.22±0.95%, P<0.05). The co-administration of CpG ODN and 5-FU also significantly enhanced the lytic activity of NK cells when compared with the treatment with 5-FU alone (12.03±1.42%, P<0.05).

CONCLUSION: The present data suggests that CpG ODN used as single therapeutic agent triggers anti-tumor immune response to inhibit the growth of implanted hepatoma and reverses the immunosuppression caused by the chemotherapy with 5-FU.

Relationships between Pregnancy and Vitamin B-6 Nutriture on Brain 3-Hydroxykynurenine Concentrations in Mice

The kynurenine (KYN) pathway of tryptophan metabolism produces several neuroactive metabolites, including 3-hydroxykynurenine (3HK). The pathway is subject to regulation by a number of effectors including pregnancy and availability of vitamin B-6. Vitamin B-6 depleted humans and animals excrete abnormally high concentrations of KYN metabolites in urine. In pregnancy, vitamin B-6 deficiency is commonly seen, and tryptophan metabolism is often found to be altered. We measured concentrations of 3HK in brains of DBA/2Ibg and A/Ibg mice as functions of pregnancy and dietary level of vitamin B-6. Pregnant DBA mice are more susceptible to flurothyl-induced seizures than controls, pregnant A mice are not. Significant elevations of 3HK were found in brains of pregnant mice, and the increases were greater in the pregnancy-associated seizure prone DBA, than in the A mice. In the A mice, brain 3HK concentrations were negatively correlated with dietary vitamin B-6 levels, as expected; however, in the DBA mice these correlations were positive, indicating an unusual response to vitamin B-6 restriction. The accumulation of a cytotoxic, excitatory metabolite, 3HK, in brain may contribute to the increased seizure susceptibility of susceptible pregnant mice, perhaps though its effects as an endogenous modulator of excitatory amino acid receptor systems.

Evaluation of a nematode (Capillaria hepatica Bancroft, 1893) as a control agent for populations of house mice (Mus musculus domesticus Schwartz and Schwartz, 1943)

Sudden, large-scale infestations of house mice (Mus musculus domesticus) occur irregularly in the cereal-growing regions of Australia, resulting in substantial economic losses. Mathematical modelling has been used to evaluate the use of the liver nematode Capillaria hepatica as a potential agent for the biological control of mouse populations. The models suggest that C. hepatica is unlikely to be successful as a single-release control agent: instead, the parasite would need to be released when it becomes apparent that an outbreak is likely. Stage-structured models, including time delays and seasonal mouse demographic parameters, suggest that the parasite may be successful as a control agent, provided it can be introduced into the mouse population at least one year before an outbreak occurs. The optimum time for introduction is in summer or autumn. Some generalisations of this work are discussed. A parasite which affects fecundity alone is unlikely to be a good control agent, because it will destabilize the host population. Macroparasites may be unable to spread sufficiently rapidly to control sudden rises in vertebrate populations.

[[Protective action of biphenyl dimethyl dicarboxylate (DDB) against liver nuclear DNA damage induced by carcinogens]]

The protective effect of DDB against carcinogen-induced DNA damage was examined in the present investigation. Preincubation of rat liver nuclei with DDB (1 mmol/L) resulted in inhibition of binding of 3H-benzo (a) pyrene to nuclear DNA. The inhibition rate was about 60%. Unscheduled DNA synthesis (UDS) of freshly isolated rat hepatocytes induced by aflatoxin B1 (10(-7) mol/L) was also dose dependently inhibited by DDB (10(-6)-10(-3) mol/L). Oral administration of DDB at 200 mg/kg once daily for 3 days was effective to induce increase of liver cytosol glutathione-S-transferase and microsomal UDPG-transferase in mice. The results indicate that DDB is able directly or indirectly to antagonize certain carcinogen-induced DNA damages.