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Male BALB/c Mice (male + c_mouse)
Selected AbstractsVascular endothelial growth factor reduces Fas-mediated acute liver injury in miceJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 7pt2 2008Yoichi Tanaka Abstract Background and Aim:, Fulminant hepatitis is still a fatal liver disease, and no specific treatment for it has been available. Vascular endothelial growth factor (VEGF) is the focus of attention because of its various actions. We investigated the effect of vascular endothelial growth factor (VEGF) on Fas-induced fulminant hepatic failure (FHF). Method:, Male Balb/c mice were treated with an intraperitoneal injection of an anti-Fas antibody (Jo-2 Ab) with or without premedication with intraperitoneally administered human recombinant VEGF. Results:, The serum level of alanine aminotransferase (ALT) was up to 300 times higher that of normal mice following the Jo-2 Ab injection, and histological analysis revealed hepatic injury and massive hepatocyte apoptosis. The VEGF significantly suppressed an elevation in serum ALT levels and hepatocyte apoptosis. Immunohistochemically, VEGF-treated mice showed that Bcl-xL in hepatocytes was strongly expressed. Conclusions:, Since hepatocytes do not express VEGF receptors, we speculated that VEGF acts on sinusoidal endothelial cells (SECs) and promotes production of cytokines such as hepatocyte growth factor in SECs, resulting in reducing apoptosis through an increase expression of Bcl-xL in hepatocytes. We suggest that VEGF has a potent antiapoptotic effect on hepatocytes through cell,cell interaction between SECs and hepatocytes. [source] Aged mice have enhanced endocortical response and normal periosteal response compared with young-adult mice following 1 week of axial tibial compressionJOURNAL OF BONE AND MINERAL RESEARCH, Issue 9 2010Michael D Brodt Abstract With aging, the skeleton may lose its ability to respond to positive mechanical stimuli. We hypothesized that aged mice are less responsive to loading than young-adult mice. We subjected aged (22 months) and young-adult (7 months) BALB/c male mice to daily bouts of axial tibial compression for 1 week and evaluated cortical and trabecular responses using micro,computed tomography (µCT) and dynamic histomorphometry. The right legs of 95 mice were loaded for 60 rest-inserted cycles per day to 8, 10, or 12,N peak force (generating mid-diaphyseal strains of 900 to 1900 µ, endocortically and 1400 to 3100 µ, periosteally). At the mid-diaphysis, mice from both age groups showed a strong anabolic response on the endocortex (Ec) and periosteum (Ps) [Ec.MS/BS and Ps. MS/BS: loaded (right) versus control (left), p,<,.05]. Generally, bone formation increased with increasing peak force. At the endocortical surface, contrary to our hypothesis, aged mice had a significantly greater response to loading than young-adult mice (Ec.MS/BS and Ec.BFR/BS: 22 months versus 7 months, p,<,.001). Responses at the periosteal surface did not differ between age groups (p,>,.05). The loading-induced increase in bone formation resulted in increased cortical area in both age groups (loaded versus control, p,<,.05). In contrast to the strong cortical response, loading only weakly stimulated trabecular bone formation. Serial (in vivo) µCT examinations at the proximal metaphysis revealed that loading caused a loss of trabecular bone in 7-month-old mice, whereas it appeared to prevent bone loss in 22-month-old mice. In summary, 1 week of daily tibial compression stimulated a robust endocortical and periosteal bone-formation response at the mid-diaphysis in both young-adult and aged male BALB/c mice. We conclude that aging does not limit the short-term anabolic response of cortical bone to mechanical stimulation in our animal model. © 2010 American Society for Bone and Mineral Research [source] Influences of Helicobacter pylori on gastric angiogenesis and ulcer healing in miceJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 9 2002Edhi Gunawan Abstract Background and Aims:Helicobacter pylori infection is associated with peptic ulcers; however, it is unclear whether the bacterium delays ulcer healing. We investigated the influence of H. pylori on ulcer healing in mice. We also examined the influence of H. pylori infection on angiogenesis. Methods: An acetic acid ulcer was made in male BALB/c mice. Three days later (day 0), the animals were inoculated with H. pylori SS1 strain. The healing process of the ulcer was examined macroscopically and microscopically on days 0, 6 and 9. The index of angiogenesis was also determined using carmine dye injection. Results: On day 0, angiogenesis began at the ulcer margin while the mucosal epithelia had not yet regenerated. On days 6 and 9, angiogenesis and epithelial regeneration developed and ulcer size reduced. These phenomena were significantly suppressed in mice infected with H. pylori. Conclusion:Helicobacter pylori infection significantly suppressed angiogenesis and delayed ulcer healing. These results indicate that H. pylori plays an important role in ulcer healing. © 2002 Blackwell Publishing Asia Pty Ltd [source] Systemic effect of Fructus Psoraleae extract on bone in micePHYTOTHERAPY RESEARCH, Issue 10 2010Ricky W. K. Wong Abstract Fructus Psoraleae extract is used in China for the treatment of bone diseases. The objective of the study was to investigate the systemic effect of Fructus Psoraleae extract consumption on bone histomorphology. Sixteen 8-week-old male BALB/c mice were divided into control and experimental groups. In the control group, eight mice were fed daily with distilled water. In the experimental group, eight mice were fed daily with distilled water mixed with Fructus Psoraleae extract. The mice were kept for 5 weeks and then killed. Using micro-computed tomography, 20 micro-tomographic slices with a separation of 0.25,mm were acquired to cover the proximal end of the left tibia of each mouse. Quantitative morphometry of the bone structure was performed. The results showed that consumption of Fructus Psoraleae extract significantly increased the bone volume/tissue volume ratio by 11.8%. The bone trabeculae increased by 7.1% in thickness so that the bone density was increased. To conclude, Fructus Psoraleae extract taken orally increases bone density and alters bone histomorphology. Copyright © 2010 John Wiley & Sons, Ltd. [source] Systemic effect of crude extract from rhizome of Drynaria fortunei on bone formation in micePHYTOTHERAPY RESEARCH, Issue 4 2006Ricky W. K. Wong Abstract The structure of the bones of mice with and without consumption of Gusuibu extracts were compared. Twenty 8-week-old male BALB/c mice were divided into two groups. In the control group ten mice were daily fed a normal diet and distilled water for drinking. In the Gusuibu group ten mice were daily fed a normal diet and distilled water mixed with Gusuibu extract for drinking. The mice were kept for 5 weeks and were then killed. Using micro-computed tomography, 20 micro-tomographic slices with an increment of 0.25 mm were acquired to cover the proximal end of the left tibia of each mouse. Quantitative morphometry of the bone structure was performed. The results showed that consumption of Gusuibu extract increased the bone volume/tissue volume ratio by 6.45%. The bone trabeculae were increased by 10.00% in number so that the bone density was increased. To conclude, Gusuibu extract taken orally increased bone density. Copyright © 2006 John Wiley & Sons, Ltd. [source] The Encapsulation of Bleomycin Within Chitosan Based Polymeric Vesicles Does Not Alter its BiodistributionJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 4 2000J. SLUDDEN Polymeric vesicles have recently been developed from an amphiphilic chitosan derivative,palmitoyl glycol chitosan. Their potential as a drug delivery system was evaluated using the anti-cancer compound bleomycin as a model drug. Palmitoyl glycol chitosan (GCP41) was synthesised by conjugation of palmitoyl groups to glycol chitosan. Bleomycin-containing vesicles (669 nm diameter) were prepared from a mixture of GCP41 and cholesterol by remote loading. The vesicles were imaged by freeze-fracture electron microscopy and their in-vitro stability tested. Incubation of the larger vesicles with plasma in-vitro led to a reduction of mean size by 49%, a reaction not seen with control sorbitan monostearate niosomes (215 nm in size). They also showed a higher initial drug release (1 h), but GCP41 and sorbitan monostearate vesicles retained 62% and 63% of the encapsulated drug after 24 h, respectively. The biodistribution of smaller vesicles (290 nm) prepared by extrusion through a 200-nm filter was also studied in male Balb/c mice. Encapsulation of bleomycin into polymeric vesicles did not significantly alter the pharmacokinetics of biodistribution of bleomycin in male Balb/c mice although plasma and kidney levels were slightly increased. It is concluded that the extruded GCP41 vesicles break down in plasma in-vivo and hence are unlikely to offer any therapeutic advantage over the free drug. [source] Transient TWEAK overexpression leads to a general salivary epithelial cell proliferationORAL DISEASES, Issue 1 2009T Sugito Objectives:, Tumor necrosis factor-like weak inducer of apoptosis (TWEAK) is a multifunctional cytokine that has pro-apoptotic, pro-angiogenic and pro-inflammatory effects. In liver, TWEAK leads to proliferation of progenitor oval cells, but not of mature hepatocytes. This study evaluated the hypothesis that TWEAK overexpression in salivary glands would lead to the proliferation of a salivary progenitor cell. Methods:, A recombinant, serotype 5 adenoviral vector encoding human TWEAK, AdhTWEAK, was constructed, initially tested in vitro, and then administered to male Balb/c mice via cannulation of Wharton's duct. TWEAK expression in vivo was monitored as protein secreted into saliva and serum by enzyme-linked immunosorbent assays. Salivary cell proliferation was monitored by proliferating cell nuclear antigen staining and apoptosis was monitored using TUNEL staining. Results:, AdhTWEAK administration led to a dose-dependent, transient TWEAK protein expression, detected primarily in saliva. Salivary epithelial cell proliferation was generalized, peaking on ,days 2 and 3. TWEAK expression had no detectable effect on apoptosis of salivary epithelial cells. Conclusion:, Transient overexpression of TWEAK in murine salivary glands leads to a general proliferation of epithelial cells vs a selective stimulation of a salivary progenitor cell. [source] Chemomodulatory effects of Azadirachta indica on the hepatic status of skin tumor bearing micePHYTOTHERAPY RESEARCH, Issue 3 2006Ashwani Koul Abstract The liver plays an important role in the modulation of the process of carcinogenesis, as it is the primary site for the biotransformation of xenobiotics including carcinogens as well as anticancer drugs. The present study was designed to evaluate the biochemical alterations occurring in the liver of 7,12-dimethylbenz(a)anthracene (DMBA) induced skin tumor bearing male Balb/c mice and their modulation by aqueous Azadirachta indica leaf extract (AAILE). It was observed that skin tumor induction caused hepatic damage characterized by a decreased hepatosomatic index and significantly increased (p < 0.001) activities of the hepatic tissue injury marker enzymes, namely alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase. However, upon treatment with AAILE, the above-mentioned alterations, including the increased activities of hepatic tissue injury marker enzymes, were significantly reversed, which signified the hepato-protective efficacy of Azadirachta indica. Increased oxidative stress was also observed in the hepatic tissue of skin tumor bearing mice as revealed by a significant increase (p < 0.001) in lipid peroxidation levels and a decrease in reduced glutathione contents and activities of various antioxidant enzymes studied, namely glutathione-S-transferase, glutathione peroxidase and glutathione reductase. The AAILE treatment reduced oxidative stress by decreasing lipid peroxidation levels and enhancing the reduced glutathione contents and activities of various antioxidant enzymes. The activities of the xenobiotic biotransformation enzymes, namely cytochrome P450, cytochrome b5 and glutathione-S-transferase, were found to be decreased in the hepatic tissue of tumor bearing mice. Treatment with AAILE further caused a decrease in the activity of cytochrome P450 and cytochrome b5, whereas it up-regulated the activity of glutathione-S-transferase. The significance of these observations with respect to the progress of the process of carcinogenesis is explained in the present research article. Copyright © 2006 John Wiley & Sons, Ltd. [source] Role of selenium in regulation of spermatogenesis: Involvement of activator protein 1BIOFACTORS, Issue 3 2005Sonia Shalini Abstract Selenium (Se) is involved in the process of male reproduction. Several studies have been carried out to find the mechanism of Se action through identified selenoproteins. Especially selenoenzyme phospholipid glutathione peroxidase (PHGPx, GPx-4) plays a pivotal role in regulating spermatogenesis. However, the action of selenium is best known as an antioxidant which acts through various selenoproteins viz. glutathione peroxidase, thioredoxin reductase and selenoprotein P. Oxidative stress is currently being considered a leading cause of male infertility. Presently, the involvement of redox active transcription factor, AP1 (Activator protein1) in testicular function was studied. AP1 is redox sensitive and also controls cell proliferation. The effects of Se might be mediated through it. Different Se status - deficient, adequate and excess Se - were generated in male Balb/c mice by feeding yeast based selenium deficient diet and deficient diet supplemented with Se as sodium selenite (0.2 and 1 ppm Se), respectively, for a period of 4 and 8 weeks. Se status was checked by measuring the Se levels and glutathione peroxidase (GSH-Px) activity in testis and liver. The reproductive potential of mice was affected at these changed Se levels. Changes in the activity of superoxide dismutase (SOD), levels of reduced glutathione (GSH) and oxidized glutathione (GSSG) were observed indicating increased oxidative stress at both the levels. Further, changes in the mRNA expression of GSH-Px, ,-glutamylcysteine synthetase ,GCS) and Mn superoxide dismutase (MnSOD) were observed. Decrease in cjun and cfos mRNA levels were observed at both the Se status (deficient and excess) which might be responsible for decreased germ cell number, differentiation and reduced fertility observed at the altered Se levels. [source] | ||||||||||