Gastric Gavage (gastric + gavage)

Distribution by Scientific Domains

Selected Abstracts

Bacterial antigens alone can influence intestinal barrier integrity, but live bacteria are required for initiation of intestinal inflammation and injury

Beate C. Sydora PhD
Abstract Intestinal flora plays a critical role in the initiation and perpetuation of inflammatory bowel disease. This study examined whether live fecal bacteria were necessary for the initiation of this inflammatory response or whether sterile fecal material would provoke a similar response. Three preparations of fecal material were prepared: (1) a slurry of live fecal bacteria, (2) a sterile lysate of bacterial antigens, and (3) a sterile filtrate of fecal water. Each preparation was introduced via gastric gavage into the intestines of axenic interleukin-10 gene-deficient mice genetically predisposed to develop inflammatory bowel disease. Intestinal barrier integrity and degrees of mucosal and systemic inflammations were determined for each preparation group. Intestinal barrier integrity, as determined by mannitol transmural flux, was altered by both live fecal bacterial and sterile lysates of bacterial antigens, although it was not altered by sterile filtrates of fecal water. However, only live fecal bacteria initiated mucosal inflammation and injury and a systemic immune response. Fecal bacterial antigens in the presence of live bacteria and sterile fecal bacterial antigens have different effects on the initiation and perpetuation of intestinal inflammation. [source]

One-year dog toxicity study of D-002, a mixture of aliphatic alcohols

Celia Alemán
Abstract D-002 is a mixture of high-molecular-weight aliphatic alcohols, obtained from bees wax (Apis mellifera), with mild anti-inflammatory properties and effective anti-ulcer activities demonstrated in experimental models. This study investigated the oral toxicity of D-002 administered for 1 year to beagle dogs. Twenty-four beagle dogs (12 males and 12 females) were distributed randomly in three experimental groups (four animals per group): a control and two treated groups received D-002 at 50 and 250 mg kg,1 (7 days/week) by gastric gavage. Overall, D-002 was well tolerated throughout the study. No signs or symptoms of toxicity were observed, and no mortality occurred during the study. All groups showed similar weight gain and food consumption. No hematological, blood biochemical or histopathological disturbances attributable to treatment were observed. This study shows no drug-related toxicity induced by long-term administration of up to 250 mg kg,1 D-002 to beagle dogs. Copyright © 2001 John Wiley & Sons, Ltd. [source]

Experimental study of the safety of the selective COX-2 inhibitor, celecoxib, for gastric mucosa

Jun Ting LI
OBJECTIVE: To compare the gastric mucosal damage induced by a COX-2 inhibitor, celecoxib, and a conventional NSAID, indomethacin. METHODS: A rat model of NSAID-induced gastric mucosal damage was prepared for indomethacin and celecoxib separately (n = 8). After gastric damage was induced by 100% ethanol, celecoxib was administered by gastric gavage (n = 8). Gastric mucosal concentrations of 6-keto-PGF1, and TXB2 and the lesion index (LI) were measured. Morphological changes of the gastric mucosa were assessed under light and scanning electron microscopy. RESULTS: Indomethacin caused marked gastric damage (LI: 13.38 ± 2.06) and significant reduction of the concentrations of 6-keto-PGF1, and TXB2 (P < 0.01), Celecoxib did not produce necrotic injuries on healthy gastric mucosa (LI: 0), but the mucosal injuries previously induced by ethanol worsened after its administration (LI: 37.19 ± 3.34 vs 19.90 ± 2.28, P < 0.01). CONCLUSIONS: Inhibition of COX-1 is the major mechanism of NSAIDs in producing gastric mucosal damage. As a selective COX-2 inhibitor, celecoxib does not produce toxic injuries of the healthy gastric mucosa, and is thus safer than conventional NSAID. However, when administered in the presence of an altered gastric mucosa, gastric injuries were worsened. [source]

Metallothionein as a biomarker for mercury in tissues of rat fed orally with cinnabar

Zhi-Yong Huang
Abstract Cinnabar, as one of the most widely used mineral drugs in traditional Chinese medicines, has been proven to have prominent curative effects in clinical use for more than 2000 years. But the safety and toxicity of the drug has been under constant debate in clinic usage. Metallothionein (MT) contains about 30% of cysteine in the molecule, and plays an important detoxification role against heavy metals. In this study, it was used as a biomarker to assess mercurial accumulation in rats fed orally with cinnabar. After feeding rats with cinnabar by gastric gavage at different dosages and at different times, the distribution of heavy metals (including mercury, copper and zinc) and MT was investigated among rat tissues, including liver, kidney, heart, brain, testis and blood. Metals and MT determinations were carried out using inductively coupled plasma mass spectrometry (ICP-MS) and a modified mercury saturation assay technique respectively. The results indicated that mercury was easily accumulated in the tissues of rats exposed to cinnabar, especially in kidney. For example: at a feeding dosage of 5 g kg,1 (bw) for 4 weeks, the mercury concentrations in kidney were 13, 8.7, 21.6 and 26 times those in liver, testis, brain and heart respectively; and at 2.5 g kg,1 (bw) for 2 weeks, the mercury concentrations in kidney were 21, 2.1, 3 and 21 times those in liver, testis, brain and heart respectively. In addition, mercury in kidney and liver of all cinnabar groups was significantly higher than that of the control group (P < 0.01). A high positive correlation observed between MT concentrations and mercury levels in both liver and kidney (R2 = 0.9299, P < 0.02 for liver; R2 = 0.9923, P < 0.0008 for kidney) indicated that MT could be used as a biomarker for mercury in tissues. Copyright © 2004 John Wiley & Sons, Ltd. [source]


Hou-Qin Xiao
SUMMARY 1Accumulating evidence suggests that vitamin D and its analogues are renoprotective. However, the precise mechanisms and the molecular targets by which active vitamin D exerts its beneficial effects remain obscure. The objective of the present study was to evaluate the effect of active vitamin D on rats with puromycin aminonucleoside (PAN) nephropathy, a model that is characterized by predominant podocyte injury. 2The PAN nephropathy rats were created by a single intravenous injection of 100 mg/kg PAN. Changes in renal pathology and podocyte numbers were observed. Real-time polymerase chain reaction (PCR) was performed to examine mRNA expression of nephrin, transforming growth factor (TGF)-,1 and bone morphogenetic protein (BMP)-7. Protein expression of nephrin, TGF-,1, BMP-7 and p-Smad2/3 and p-Smad1/5/8 was examined by immunofluorescence, immunohistochemistry and western blotting, respectively. Rats were treated with 1,25(OH)2D3 by gastric gavage at a dose of 2.5 µg/kg per day, starting 2 days before PAN injection and continuing throughout the experiment. 3A single injection of PAN induced massive proteinuria and elevated serum creatinine on Day 7, both of which were significantly suppressed by 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). Immunofluorescence and real-time PCR of the podocyte-associated protein nephrin revealed reduced and discontinuous staining and this change was reversed by 1,25(OH)2D3. In PAN nephropathy rats, TGF-,1 and p-Smad2/3 expression was upregulated, whereas that of BMP-7 and p-Smad1/5/8 was downregulated. Treatment with 1,25(OH)2D3 significantly restored BMP-7/Smad signalling while suppressing TGF-,1/Smad signalling. 4In conclusion, 1,25(OH)2D3 can ameliorate podocyte damage and proteinuria induced by PAN. The beneficial effects of 1,25(OH)2D3 on podocytes may be attributable, in part, to direct modulation of TGF-,1/BMP-7 signalling. [source]

The influence of curcumin and manganese complex of curcumin on cadmium-induced oxidative damage and trace elements status in tissues of mice

Vladislav Eybl
Abstract Curcumin (diferuoyl methane) from turmeric is a well-known biologically active compound. It has been shown to ameliorate oxidative stress and it is considered to be a potent cancer chemopreventive agent. In our previous study the antioxidative effects of curcumin in cadmium exposed animals were demonstrated. Also manganese exerts protective effects in experimental cadmium intoxication. The present study examined the ability of the manganese complex of curcumin (Mn-curcumin) and curcumin to protect against oxidative damage and changes in trace element status in cadmium-intoxicated male mice. Curcumin or Mn-curcumin were administered at equimolar doses (0.14 mmol/kg b.w.) for 3 days, by gastric gavages, dispersed in methylcellulose. One hour after the last dose of antioxidants, cadmium chloride (33 µmol/kg) was administered subcutaneously. Both curcumin and Mn-curcumin prevented the increase of hepatic lipid peroxidation , expressed as MDA level, induced by cadmium intoxication and attenuated the Cd-induced decrease of hepatic GSH level. No change in hepatic glutathione peroxidase or catalase activities was found in Cd-exposed mice. A decreased GSH-Px activity was measured in curcumin and Mn-curcumin alone treated mice. Neither curcumin nor Mn-curcumin treatment influenced cadmium distribution in the tissues and did not correct the changes in the balance of essential elements caused by Cd-treatment. The treatment with Mn-curcumin increased the Fe and Mn content in the kidneys of both control and Cd-treated mice and Fe and Cu content in the brain of control mice. In conclusion, regarding the antioxidative action, introducing manganese into the curcumin molecule does not potentiate the studied effects of curcumin. Copyright © 2005 John Wiley & Sons, Ltd. [source]