| Kinase Assay: |
| Hereditas. 2011 Nov;148(4-5):118-24. | | Dl-α-tocopherol enhances the herbicide 1,1'-dimetyl-4,4'-bipyridium dichloride (paraquat, PQ) genotoxicity in cultured anuran leukocytes.[Pubmed: 22150823] |
METHODS AND RESULTS:
This cytogenetic and pharmacological study attempts to clarify genotoxicity-enhancement-effect of DL-alpha-Tocopherol (one form of vitamin E) in combination with the herbicide 1,1'-dimetyl-4,4'-bipyridium dichloride (paraquat, PQ) on cultured anuran leukocytes using the superoxide dismutase-mimic Mn(III)tetrakis(1-methyl-4-pyridyl)porphyrin (Mn(III)TMpyP), the hydrogen peroxide-scavenger catalase and the electron donor nicotinamide adenine dinucleotido phosphate (NADPH).DL-alpha-Tocopherol only did not induce any structural chromosomal damage in the leukocytes. PQ plus DL-alpha-Tocopherol, however, enhanced the genotoxic effect of PQ. Furthermore, PQ plus DL-alpha-Tocopherol-enhanced chromosomal damage was also inhibited by Mn(III)TMpyP plus catalase.
CONCLUSIONS:
These results suggest that DL-alpha-Tocopherol in combination with PQ functions as an electron donor to PQ. | | J Cell Physiol. 1997 Sep;172(3):351-60. | | dl-alpha-tocopherol, a potent inhibitor of phorbol ester induced shape change of erythro- and megakaryoblastic leukemia cells.[Pubmed: 9284955] | Synthetic vitamin E, DL-alpha-Tocopherol, added to a human erythroleukemia HEL and a megakaryoblastic leukemia, Meg-01, cell culture produced potent dose-dependent inhibition of phorbol ester-induced adhesion and of the morphologic changes accompanying it.
METHODS AND RESULTS:
The inhibition was reversible by withdrawal of supplemental vitamin E from the medium. DL-alpha-Tocopherol also inhibited protein kinase C activity both at baseline and after phorbol ester stimulation. Arachidonic acid stimulated protein kinase C activity of erythroleukemia cells and promoted their adhesion, an effect that was also inhibited by DL-alpha-Tocopherol. Introduction of a protein kinase C-neutralizing antibody or a protein kinase C-inhibitor substrate into permeabilized HEL cells inhibited phorbol ester-induced adhesion and shape change. DL-alpha-Tocopherol also affected the cellular distribution of protein kinase C, shifting the major portion of the enzyme to the cytosol fraction and reducing phorbol ester-induced membrane association of the enzyme.
CONCLUSIONS:
Thus, protein kinase C appears to mediate shape change and adhesion, both of which are strongly inhibited by DL-alpha-Tocopherol. |
|
Cell. 2018 Jan 11;172(1-2):249-261.e12. doi: 10.1016/j.cell.2017.12.019.IF=36.216(2019)
Cell Metab. 2020 Mar 3;31(3):534-548.e5. doi: 10.1016/j.cmet.2020.01.002.IF=22.415(2019)
Mol Cell. 2017 Nov 16;68(4):673-685.e6. doi: 10.1016/j.molcel.2017.10.022.IF=14.548(2019)
ACS Nano. 2018 Apr 24;12(4): 3385-3396. doi: 10.1021/acsnano.7b08969.IF=13.903(2019)
Nature Plants. 2016 Dec 22;3: 16206. doi: 10.1038/nplants.2016.205.IF=13.297(2019)
Sci Adv. 2018 Oct 24;4(10): eaat6994. doi: 10.1126/sciadv.aat6994.IF=12.804(2019)