bimosiamose-disodium and Disease-Models--Animal

The clinical and experimental management of stroke has not reached the therapeutic success seen in other medical conditions associated with ischemia/reperfusion. In this work, we investigated the effect of a small molecule selectin inhibitor TBC-1269, in animals subjected to global cerebral ischemia (GCI) and controlled hemorrhagic shock (CHS).. Forty-eight male Sprague-Dawley rats weighting between 275 g and 300 g were subjected to a model of GCI and CHS. Three groups of animals were included in this study (n = 16 per group): sham/saline (group 1); GCI/CHS/Saline (group 2); GCI/CHS/TBC-1269 (group 3). Experimental design consisted of bilateral carotid artery occlusion for 20 minutes, and the development of CHS until a mean arterial pressure of 50 mm Hg was reached. At 20 minutes, clamps were released, and resuscitation was achieved with normal saline, and the end point was to attain a mean arterial pressure of 80 mm Hg. Treatment at the beginning of resuscitation included either normal saline (groups 1 and 2) or TBC-1269 (25 mg/kg, group 3). The following indices were evaluated: brain tissue myeloperoxidase, average numbers of ischemic neurons, and 7-day survival.. Brain myeloperoxidase was decreased in animals treated with TBC-1269, although this difference was not statistically significant. Treated animals demonstrated a significant smaller amount of ischemic neurons than the controls. Survival was also improved from 40% in controls to 80% with TBC-1269 treatment. This difference was statistically significant.. The use of a small molecule selectin inhibitor, TBC-1269, had a protective effect in this model of GCI and CHS, as evidenced by decreased numbers of ischemic neurons and improved survival rates.

Topics: Animals; Biphenyl Compounds; Brain Ischemia; Cell Adhesion Molecules; Disease Models, Animal; Male; Mannose; Mannosides; Neutrophil Infiltration; Peroxidase; Rats; Rats, Sprague-Dawley; Shock, Hemorrhagic

Preliminary studies in our laboratories indicate that a recently discovered synthetic drug, TBC-1269, acts as a multiple selectin blocker and provides protection against tissue damage in rats that are subjected to severe liver ischemia/reperfusion. Here, we report that this effect is dose and time dependent, with its effects acting through the modulation of tumor necrosis factor (TNF)-alpha and interleukin (IL)-10.. Mice subjected to 90 min of partial (70-80%) hepatic ischemia and 3 h of reperfusion were divided into eight groups (n=6/group): sham, ischemic control (IC), three groups of TBC-1269-treated animals at different concentrations (10, 20, 40, mg/kg) and another three groups of TBC-1269 given at 40 mg/kg at different times of administration: 15 min prereperfusion but after ischemia (no pretreatment), at the time of reperfusion, and at 15 min after reperfusion. The parameters measured at 3 h of reperfusion included liver function tests (alanine aminotransferase and aspartate aminotransferase), histopathology analysis and measurements using enzyme-linked immunosorbent assay in serum of TNF-alpha and IL-10. Statistical analysis included analysis of variance with P values of <0.05 for significance. Results were expressed as mean +/- SD.. The liver function tests showed statistically significant differences between the ischemic control group and both the sham group and the group treated with 40 mg/kg at the time of reperfusion (40@RP). These results correlated well with the histopathological analysis in that we found no difference in vacuolization, congestion, and necrosis between the 40@RP group and the sham group. The TNF-alpha and the IL-10 also reflected the protection observed in histopathology, with a decrease in TNF- alpha from the high levels observed in the IC (32 +/- 2.32 pg/mL) to a lower level of 8.5 +/- 4.04 mg observed in the 40@RP group, and an increment in the levels of the protective IL-10 from 2.8 +/- 2.9 pg/mL in the IC group versus 37.9 +/- 11.6 pg/mL in the 40@RP treated group (P<0.05). Lower doses and different times of administration of TBC-1269 did not show a protective effect. The IC group showed no difference in damage by histopathology or liver enzymes compared to the rest of the groups, except the 40@RP group.. In this work, we demonstrated that the small molecule multiple selectin inhibitor (TBC-1269) offered significant protection for the ischemic liver when given at 40 mg/kg at the time of perfusion. Lower doses and different times of administration did not show the optimal drug effect. The protection observed in the liver function tests (alanine aminotransferase and aspartate aminotransferase) and histopathology in this group was also reflected in the significant decrease in serum TNF-alpha and equally significant increase in serum protective IL-10.

Topics: Animals; Biphenyl Compounds; Disease Models, Animal; Dose-Response Relationship, Drug; Interleukin-10; Liver; Male; Mannose; Mannosides; Mice; Mice, Inbred C57BL; Reperfusion Injury; Selectins; Tumor Necrosis Factor-alpha

Experiments in rodents have demonstrated an important role for selectins in kidney ischemia-reperfusion injury (IRI). However, the relevance of this in larger mammals, as well as the impact on long-term structure and function is unknown. We tested the hypothesis that small molecule selectin ligand inhibition attenuates IRI, cellular inflammation, and long-term effects on renal interstitial fibrosis. We used a porcine model of kidney IRI and used Texas Biotechnology Corporation (TBC)-1269, a selectin ligand inhibitor. Renal function, tissue inflammation, and tubulointerstitial fibrosis development were evaluated up to 16 weeks. Both warm and cold ischemia models were studied for relevance to native and transplant kidney injury. Pigs treated with TBC-1269 during 45 min of warm ischemia (WI) showed significantly increased glomerular filtration rate compared to control animals. In pigs with severe IRI (WI for 60 min), TBC-1269 treatment during IRI significantly increased renal recovery. Cellular inflammation was strongly reduced, particularly influx of CD4 cells. Quantitative measurement of fibrosis by picrosirius red staining showed strong reduction in TBC-1269-treated groups. TBC-1269 also reduced cold IRI, inflammation, and fibrosis in kidneys preserved for 24 h at 4 degrees C and autotransplanted. The selectin ligand inhibitor TBC-1269 provides a novel and effective approach to attenuate IRI in both warm and cold ischemia in large mammals, in both short and long terms. Selectin ligand inhibition is an attractive strategy for evaluation in human kidney IRI.

Topics: Animals; Biphenyl Compounds; Disease Models, Animal; Fibrosis; Immunohistochemistry; Kidney; Ligands; Male; Mannose; Mannosides; Molecular Structure; Nephritis, Interstitial; Protective Agents; Reperfusion Injury; Selectins; Swine; T-Lymphocytes

The purpose of this study was to investigate the regulatory effect of a small molecule selectin inhibitor in the liver by examining the functional, structural, and survival response of animals subjected to hemorrhagic shock and to determine the liver infiltration of neutrophils and the regulation of chemokine expression. Selectins play an important role in the development of the lesions associated with ischemia/reperfusion and hemorrhagic shock. Blocking individually the selectin family of adhesion molecules with monoclonal antibodies has resulted in better organ function and survival. To our knowledge, there are no studies demonstrating the beneficial effect of multiple selectin blockade with a small molecule inhibitor under conditions of hemorrhagic shock.. Forty-eight Sprague-Dawley rats were subjected to hemorrhagic shock. Three groups of animals were included (n = 16/group), i.e., the sham, control, and treated groups, which received a small molecule selectin inhibitor (TBC-1269) at 25 mg/kg body weight after the bleeding began. The following parameters were evaluated: fluid requirements during resuscitation, liver injury tests (aspartate aminotransferase, alanine aminotransferase), liver histology and myeloperoxidase, and macrophage inflammatory protein-2 mRNA and cytokine-induced neutrophil chemoattractant mRNA in liver tissue, and animal survival at 3 days. Statistical analysis included Student's t test and analysis of variance when indicated.. Significant improvement in liver function and histology was noted in the treated group. Survival was also improved, although it is not known whether liver failure was the most proximate cause of lethality. Infiltration of neutrophils, measured by tissue myeloperoxidase, was significantly decreased in livers of treated animals. No significant changes were noted in fluid requirements. The small molecule selectin inhibitor group showed a down-regulating effect on liver macrophage inflammatory protein-2 and cytokine-induced neutrophil chemoattractant mRNA expression associated with less accumulation of neutrophils in the liver.. This study supports the role that selectins play in the pathogenesis of hemorrhagic shock. The mechanism of protection seen after multiple selectin blockade (TBC-1269) centered, in part, around the infiltration of liver neutrophils, probably dependent on the induction of macrophage inflammatory protein-2 and cytokine-induced neutrophil chemoattractant mRNA expression in liver tissue.

Topics: Analysis of Variance; Animals; Biphenyl Compounds; Blotting, Northern; Chemokines; Disease Models, Animal; Down-Regulation; Liver; Male; Mannose; Mannosides; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; RNA, Messenger; Selectins; Shock, Hemorrhagic

The selectin family of adhesion molecules plays a key role in the neutrophil-mediated injury observed after ischemia and reperfusion. In our study, we investigated the effects of TBC-1269, a novel small-molecule, nonoligosaccharide inhibitor of P-, E-, and L-selectin binding, in the liver inflammatory response after 90 minutes of warm ischemia.. Total liver ischemia was produced in Sprague-Dawley rats for 90 minutes using an extracorporeal portosystemic shunt. The animals were divided into five groups including: the sham (group 1), ischemic control (group 2) receiving only the vehicle, and the treated groups receiving TBC-1269 at a dose of 25 mg/kg at different times of administration: 15 minutes before reperfusion (group 3), at reperfusion (group 4), and 15 minutes after reperfusion (group 5). The following indices were analyzed: 7-day survival, liver injury tests, liver tissue myeloperoxidase as an index of neutrophil infiltration, and liver histology.. TBC-1269 treated groups experienced a significant increase in survival compared with controls. Best overall survival, 70%, was observed when TBC-1269 (Texas Biotechnology Corporation, Houston, TX) was administered 15 minutes before reperfusion (p < 0.05). This group also showed a marked decrease (p < 0.05) in liver enzyme levels at 6 hours after reperfusion. Neutrophil migration was also significantly ameliorated (81%), as reflected by decreased myeloperoxidase levels. We observed improved histologic damage scores in the treated group compared with controls (p < 0.05).. A small-molecule selectin inhibitor (TBC-1269) had a protective effect in livers subjected to 90 minutes of warm hepatic ischemia and 6 hours of reperfusion by decreasing neutrophil infiltration, migration and subsequent tissue damage. The best protective effect was achieved when the compound was administered 15 minutes before reperfusion. These findings offer a new therapeutic alternative for protection against ischemia and reperfusion injury.

Topics: Animals; Antibodies, Monoclonal; Biphenyl Compounds; Disease Models, Animal; Inflammation; Liver; Mannose; Mannosides; Necrosis; Neutrophil Activation; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Selectins