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Conversion of phylloquinone (Vitamin K1) into menaquinone-4 (Vitamin K2) in mice: two possible routes for menaquinone-4 accumulation in cerebra of mice.\nOkano T, Shimomura Y, Yamane M, Suhara Y, Kamao M, Sugiura M, Nakagawa K.\nJ Biol Chem. 2008 Apr 25;283(17):11270-9. Epub 2007 Dec 14. \nPMID: 18083713 \ndoi: 10.1074/jbc.M702971200 \n\nOur results suggest that cerebral menaquinone-4 originates from phylloquinone intake and that there are two routes of accumulation, one is the release of menadione from phylloquinone in the intestine followed by the prenylation of menadione into menaquinone-4 in tissues, and another is cleavage and prenylation within the cerebrum.

Induction of ovarian cancer cell apoptosis by 1,25-dihydroxyvitamin D3 through the down-regulation of telomerase. Jiang F, Bao J, Li P, Nicosia SV, Bai W. J Biol Chem. 2004 Dec 17;279(51):53213-21. Epub 2004 Oct 12. PMID: 15485861 doi: 10.1074/jbc.M410395200 Overall, the study suggests that the down-regulation of telomerase activity by 1,25(OH)2VD3 and the resulting cell death are important components of the response of OCa cells to 1,25(OH)2VD3-induced growth suppression. Progressive shortening of telomere associated with cell divisions limits the life span of normal cells and eventually leads to senescence. To become immortal, human cancers including OCa are invariably associated with activation of mechanism that maintains telomere length. Approximately 85-90% of cancers show reactivation of telomerase. The present study shows that telomerase in OCa cells is down-regulated by 1,25(OH)2VD3. Down-regulation of telomerase is due to decreased stability of hTERT mRNA rather than VDRE-mediated transcriptional repression through the putative VDRE present in the regulatory region of the hTERT gene. It is known that the inhibition of telomerase may lead to a phenotypic lag during which cells would continue to divide until the point at which the telomeres became critically short. This phenomenon may explain why the apoptotic induction by 1,25(OH)2VD3 needs the treatment for more than 6 days. As mentioned in the results, no detectable shortening of telomeric repeats was observed in parental OVCAR3 cells after 9 days of treatment with 1,25(OH)2VD3 (Fig. 4D). This is likely due to the fact that the short telomere (about 3 kb) in OVCAR3 cells is very close to the minimal length required for survival and that cells with detectably shorter telomere may have been selected against apoptosis. It has been shown that transformed human cells enter crisis once the terminal restriction fragment of the telomere reaches a length of about 4 kb. This is insufficient to protect chro

Conjugated linoleic acid promotes human adipocyte insulin resistance through NFkappaB-dependent cytokine production. Chung S, Brown JM, Provo JN, Hopkins R, McIntosh MK. J Biol Chem. 2005 Nov 18;280(46):38445-56. Epub 2005 Sep 9. PMID: 16155293 doi: 10.1074/jbc.M508159200 Collectively, these data demonstrate for the first time that trans-10, cis-12 CLA promotes NFkappaB activation and subsequent induction of IL-6, which are at least in part responsible for trans-10, cis-12 CLA-mediated suppression of peroxisome proliferator-activated receptor gamma target gene expression and insulin sensitivity in mature human adipocytes. In summary, our in vitro data demonstrate that a physiological level of trans-10, cis-12 CLA activates NFκB- and ERK1/2-dependent cytokine production, which together suppress PPARγ and Glut4 levels and lead to impaired glucose uptake. Studies are currently under way examining 1) how CLA regulates PPARγ and the expression of its target genes, 2) the specific signaling role of SV cells and adipocytes in mediating the TG-lowering actions of CLA, and 3) the CLA-induced, upstream signal that activates NFκB and ERK1/2.

Berberine inhibits metastasis of nasopharyngeal carcinoma 5-8F cells by targeting Rho kinase-mediated Ezrin phosphorylation at threonine 567. Tang F, Wang D, Duan C, Huang D, Wu Y, Chen Y, Wang W, Xie C, Meng J, Wang L, Wu B, Liu S, Tian D, Zhu F, He Z, Deng F, Cao Y. J Biol Chem. 2009 Oct 2;284(40):27456-66. Epub 2009 Aug 3. PMID: 19651779

Marambaud P, Zhao H, Davies P. Resveratrol promotes clearance of Alzheimer's disease amyloid-beta peptides. J Biol Chem. 2005 Nov 11;280(45):37377-82. Epub 2005 Sep 14. PMID: 16162502 [PubMed - indexed for MEDLINE]