2-Butoxyethanol Female-Rat Model of Hemolysis and Disseminated Thrombosis: X-Ray Characterization of Osteonecrosis and Growth-Plate Suppression

Quail (Coturnix japonica) egg attenuated 2-butoxyethanol-induced enzymatic dysregulation, disseminated thrombosis and hemolytic impairment in female wistar rats

Influence of quail egg on pathologies has increased research interests and series of investigations are currently being done on its influence against these pathologies. The influence of quail egg against 2-butoxyethanol induced hemolysis and disseminated thrombosis was investigated to determine the enzymatic regulations that ensue in the amelioration of deleterious hemolytic and disseminated thrombosis displayed in female Wistar rats. Quail egg was separated into three (3) components (extracts)-quail egg yolk water soluble (QYWS) and fat soluble (QYFS), and albumen extract (QA) and the inorganic and organic compositions were characterized. Depranocytotic assaults was achieved by 250 mg/kg of 2-Butoxyethanol administered for 4 days, the clinical observation revealed a dark purple-red discoloration on the distal tails of the rats and therapeutic applications followed with 1000 mg/kg BWT of QYWS, QYFS and QA, and 15 mg/kg BWT of hydroxyurea. Morphological evaluation, haematological estimations and biochemical evaluations of the influence on the activities of sphingosine kinase-1, RNase, red cell carbonic anhydrase, lactate dehydrogenase, glutathione peroxidase and caspase-3, vis a vis the concentrations of sphingosine-1 phosphate, selenium and zinc (plasma and urine). In vitro anti-inflammatory influence of quail egg components were investigated against hemolysis and key enzymes of inflammation-cycloxygenase, lipoxygenase and β-glucuronidase. The in vitro anti-inflammatory effects of QYWS, QYFS and QA were concentration dependent from 200 to 800 μg/ml against hemolysis and the key enzymes of inflammation. The characterization of inorganic and organic bioactive composition of the yolk and albumen revealed the presence of folic acid, cobalamin, pyridine, riboflavin, ascorbic acid as well as vitamins D and E, selenium, zinc, iron and calcium. These had reflected in the attenuation of the induced hemolytic and disseminated thrombosis by regulations of enzymes linked to the infarction, apoptosis and oxidative stress characterized in sickle cell index.

2-Butoxyethanol model of haemolysis and disseminated thrombosis in female rats: a preliminary study of the vascular mechanism of osteoarthritis in the temporomandibular joint

Female rats develop haemolytic anaemia and disseminated thrombosis and infarction in multiple organs, including bone, when exposed to 2-butoxyethanol (BE). There is growing evidence that vascular occlusion of the subchondral bone may play a part in some cases of osteoarthritis. The subchondral bone is the main weight bearer as well as the source of the blood supply to the mandibular articular cartilage. Vascular occlusion is thought to be linked to sclerosis of the subchondral bone associated with disintegration of the articular cartilage. The aim of this study was to find out whether this model of haemolysis and disseminated thrombosis supports the vascular hypothesis of osteoarthritis. Six female rats were given BE orally for 4 consecutive days and the two control rats were given tap water alone. The rats were killed 26 days after the final dose. The mandibular condyles showed histological and radiological features consistent with osteoarthritis in three of the four experimental rats and in neither of the control rats. These results may support the need to explore the vascular mechanism of osteoarthritis further.

Age and dose sensitivities in the 2-butoxyethanol F344 rat model of hemolytic anemia and disseminated thrombosis

In hemolytic disorders, such as sickle cell disease and beta-thalassemia, the mechanisms of thrombosis are poorly understood. Appropriate animal models would increase the understanding of the pathophysiology of thrombosis. We previously reported that rats exposed to 2-butoxyethanol (2-BE) developed hemolytic anemia and disseminated thrombosis resembling sickle cell disease and beta-thalassemia. To characterize our model further, we investigated age- and dose-related differences in sensitivity to 2-BE. We exposed groups of 6- and 12-week-old F344 rats (5 animals/group) to 62.5, 125, and 250 mg/kg/day of 2-BE for up to 4 days. Blood was collected on days 2-4 for complete blood count and measurement of intracellular adhesion molecule-1 (ICAM-1). Histopathological evaluation was performed to find evidence of disseminated thrombosis. The maximum hemolytic response, resulting in decreased erythrocyte count and higher mean cell volume (MCV) occurred in the 12-week-old rats treated with the highest dose of 2-BE (250 mg/kg, p<0.0001). The highest increase in ICAM-1 levels occurred in the 12-week-old rats treated with 125 and 250 mg/kg 2-BE (p<0.0001). No intravascular thrombi were noted in the 6-week-old 2-BE-treated animals. The majority of intravascular thrombi occurred in the 12-week-old rats treated with 250 mg/kg 2-BE. Because our findings show age- and dose-related sensitivities, we suggest that 12-week-old rats and doses of 250 mg/kg be used in the 2-BE model.

Chemical-induced atrial thrombosis in NTP rodent studies

Cardiac thrombosis, one of the causes of sudden death throughout the world, plays a principal role in several cardiovascular diseases, such as myocardial infarction and stroke in humans. Data from studies of induction of chemical thrombosis in rodents help to identify substances in our environment that may contribute to cardiac thrombosis. Results for more than 500 chemicals tested in rodents in 2-year bioassays have been published as Technical Reports of the National Toxicology Program (NTP) http://ntp-server.niehs.nih.gov/index. We evaluated atrial thrombosis induced by these chemical exposures and compared it to similarly induced lesions reported in the literature. Spontaneous rates of cardiac thrombosis were determined for control Fischer 344 rats and B6C3F1 mice: 0% in rats and mice in 90-day studies and, in 2-year studies, 0.7% in both genders of mice, 4% in male rats, and 1% in female rats. Incidences of atrial thrombosis were increased in high-dosed groups involving 13 compounds (incidence rate: 20-100%): 2-butoxyethanol, C.I. Direct Blue 15, bis(2-chloroethoxy)methane, diazoaminobenzene, diethanolamine, 3,3'-dimethoxybenzidine dihydrochloride, hexachloroethane, isobutene, methyleugenol, oxazepam, C.I. Pigment Red 23, C.I. Acid Red 114, and 4,4'-thiobis(6-t-butyl-m-cresol). The main localization of spontaneously occurring and chemically induced thromboses occurred in the left atrium. The literature survey suggested that chemical-induced atrial thrombosis might be closely related to myocardial injury, endothelial injury, circulatory stasis, hypercoagulability, and impaired atrial mechanical activity, such as atrial fibrillation, which could cause stasis of blood within the left atrial appendage, contributing to left atrial thrombosis. Supplementary data referenced in this paper are not printed in this issue of Toxicologic Pathology. They are available as downloadable files at http://taylorandfrancis.metapress.com/openurl.asp?genre=journal&issn=0192-6233. To access them, click on the issue link for 33(5), then select this article. A download option appears at the bottom of this abstract. In order to access the full article online, you must either have an individual subscription or a member subscription accessed through www.toxpath.org.