Tordon 202C immunosuppressant

[Kathy]

Some work done by Dr. BR Blakely at the University of Saskatchewan, for more go to:
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Search&itool=pubmed_Abstract&term=%22Blakley+BR%22%5BAuthor%5D (Entrez Pubmed list of publications)

Vet Hum Toxicol. 1997 Aug;39(4):204-6. Related Articles, Links


Effect of roundup and tordon 202C herbicides on antibody production in mice.

Blakley BR.

Department of Veterinary Physiological Sciences, University of Saskatchewan, Saskatoon, Canada.

Female CD-1 mice were exposed to Tordon 202C (2,4-dichlorophenoxyacetic acid [2,4-D] and picloram) or Roundup (glyphosate) in drinking water for 26 d at concentrations ranging from 0 to 0.42% or from 0 to 1.05%, respectively. The mice were inoculated with sheep red blood cells to produce a T-lymphocyte, macrophage dependent antibody response on day 21 of the herbicide exposure period. Tordon 202C dosing reduced weight gain and water consumption at the 0.42% level of exposure. Roundup exposure did not alter weight gain or water consumption. Antibody production was unaffected by Roundup dosing, suggesting that Roundup is unlikely to cause immune dysfunction under normal application conditions.

In contrast, all levels of Tordon 202C exposure reduced antibody production by as much as 45%. The immunosuppressive activity of Tordon 202C was associated with levels more than 12 x the normal application level, although it was not determined which component of the formulation was responsible for the immunosuppression effect. The presence of immune alteration subsequent to exposure to Tordon 202C at levels marginally above the normal application levels suggests that chronic exposure to Tordon 202C in the environment has the potential to alter immune function.

 

[Kathy]

Just for good measure, here is another by Dr. Blakely:

Vet Hum Toxicol. 2002 Jun;44(3):129-32. Related Articles, Links


Species differences in normal brain cholinesterase activities of animals and birds.

Blakley BR, Yole MJ.

Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada.

The normal cholinesterase activity in brain tissue was measured in 15 mammalian and 44 avian species using the Ellman method. Enzyme activity exhibited considerable interspecies variability. In mammals, the enzyme activities ranged from approximately 2 to 10 micromole/min/g of wet tissue. With the exception of the carnivores (dog, fox, coyote), no consistency of the enzyme activity could be identified in related mammalian species. The range of interspecies differences associated with avian cholinesterase activity were approximately double when compared to the mammalian species tested. Enzyme activities in avian species ranged from approximately 10 to 30 micromole/min/g. Comparisons for uniformity of enzyme activity between closely related avian species were poor in most instances. The considerable variability of the brain cholinesterase activities in avian and mammalian species illustrates the need for reliable normal values for individual species to improve ability to monitor environmental exposure or to confirm acute poisonings associated with organophosphate or carbamate insecticides.

 

[Kathy]

An Argentine study on copper deficiency in cattle. It shows that copper deficient cattle have damage to their DNA (chromosomal aberrations).

Mutagenesis. 2004 Nov;19(6):453-6.

Association between copper deficiency and DNA damage in cattle.

Picco SJ, Abba MC, Mattioli GA, Fazzio LE, Rosa D, De Luca JC, Dulout FN.

Centro de Investigaciones en Genetica Basica y Aplicada (CIGEBA), Universidad Nacional de La Plata, 60 y 118, CC 296, B1900AVW La Plata, Argentina. [email protected]

Cattle hypocuprosis is the second most widespread mineral deficiency affecting grazing cattle. The consequences of hypocuprosis include a failure of copper metalloenzymes, many of which form part of the antioxidant defence system. This work focuses on the association between copper (Cu) plasma concentration and DNA damage in Aberdeen Angus cattle. Two-hundred and ninety-nine heparinized blood samples from 2-year-old Aberdeen Angus cows were obtained from different farms located in the Salado River basin, Argentina. Plasma copper level analysis was carried out in whole samples, while cytogenetic analysis and single cell gel electrophoresis assay (comet assay) were carried out in 82 and 217 samples, respectively. Cytogenetic analysis showed a significant increase in the frequency of abnormal metaphases in moderate/severe hypocupremic groups (groups B and C) in relation to the normocupremic group (group A) (4.5 and 1.5 abnormal metaphases/100 cells, respectively, P < 0.01). The Spearman correlation test showed a negative association between cupremic values and the yield of chromosomal aberrations (r = -0.708, P < 0.0001). In the comet assay greater migration was observed in cells from the hypocupremic group, from a median of 54 in the severe hypocupremic group to 31 in the normocupremic group (P < 0.01). Accordingly, the Spearman correlation test showed a significant positive relationship between copper levels and cells without DNA migration and a significant negative relationship between copper levels and cells with a tiny tail (P < 0.0001 in both cases). The results obtained show that hypocupremia in cattle is associated with an increase in the frequency of chromosomal aberrations as well as in DNA migration as assessed by the comet assay. Whereas the comet assay could differentiate copper plasma level groups, chromosomal aberrations only detected differences between normal and hypocupremic animals. The increase of DNA damage found in hypocupremic animals could be explained by higher oxidative stress suffered by these animals.