Differentiation-inhibitory activity

Ruedl, C., Gstrauntaler, G. and Moser, M. (1989). Differential inhibitory activity of the fungal toxin orellanine on alkaline phosphatase isoenzymes, Biochim. Biophys. Acta, 991, 280-283. 

DIA (differentiation inhibitory activity)/DRF (differentiation retarding factor)... 

Another aspect of LIF was revealed by studies on the activity that prevents differentiation of totipotent ES cells derived from normal blastocysts (Williams et al., 1988 Smith et al., 1988 Gough et al., 1989 Smith et al., 1992). It is known that to maintain the totipotency of ES cells, they must be grown on a feeder layer of fibroblasts. The activity secreted by the feeder layer fibroblasts, termed DIA (differentiation inhibitory activity) or DRF (differentiation retarding factor), has been purified, and its characteristics suggest that DIA/DRF may be identical to LIF. Indeed, not only does LIF exhibit the same activities as DIA and DRF in vitro, but also ES cells cultured with LIF can retain their totipotency. When the ES cells treated with LIF are injected into mouse blastocysts and then introduced into pseudo-pregnant females, they contribute extensively to the development of all of the somatic tissues (Williams et al., 1988 Gough et al., 1989). 

Savatier, P., Lapillonne, H., van Grunsven, L.A., Rudkin, B.B. and Samarut, J. (1996). Withdrawal of differentiation inhibitory activity/leukemia inhibitory factor up-regulates D-type cyclins and cyclin-dependent kinase inhibitors in mouse embryonic stem cells. Oncogene. Vol. 12 No. 2 pp. 309-322 ISSN 0950-9232... 

NAKANE H and ONO K (1990) Differential inhibitory effects of some catechin derivatives on the activities of human immunodeficiency virus reverse transcriptase and cellular deoyriboncleic and ribonucleic acid polymerases , Biochem, 29, 2841-5. 

Another intriguing observation is that the female sex-hormone 17/i-estradiol (28) could dramatically potentiate capsaicin responses, whereas the male hormone testosterone had marginal inhibitory activity. Sex differences in pain responses have long been known, with women being more sensitive to capsaicin-induced pain than men [94]. The differential modulation of capsaicin responses by female and male hormones might provide a rationale to explain this observation. 

Bai NS., HK, Ibarra A, Bily A, Roller M, Chen XZ, Riihl R. Iridoids from Fraxinus excelsior with Adipocyte Differentiation-Inhibitory and PPARa Activation Activity. Journal of Natural Products 2010 (73) 2-6. 

The mechanisms by which antitumor-promoters suppress the tumor promotion are not known, but may be due to the following effects (i) inhibition of polyamine metabolism (ii) inhibition of arachidonic acid metabolism (iii) protease inhibition (iv) induction of differentiation (v) inhibition of oncogene expression (vi) inhibition of PKC and (vii) inhibition of oxidative DNA damage [3,6,91]. The polyamine content of cells is correlated to their proliferative, and often, their neoplastic capabilities. A key enzyme in the polyamine biosynthetic pathway, ornithine decarboxylase (ODC), catalyzes the convertion of ornithine to putrescine. Phorbol ester promoters such as TPA cause increased ODC activity and accumulation of polyamines in affected tissues. Diacylglycerol activated PKC, and the potent tumor promoter, TPA, binds to, and activates PKC, in competition with diacylglycerol. PKC stimulation results in phosphorylation of regulatory proteins that affect cell proliferation. Some chemopreventive agents have inhibitory activity towards PKC. Refer to recent review articles for further discussion [3,6,91]. 

The differential inhibitory effect of the carboxamides on the sialidases from the influenza virus A and B was determined by extensive structure-activity... 

Zweerszeilmaker, W.M., Horbach, G.J. and Witkamp, R.F. (1997). Differential Inhibitory Effects of Phenytoin, Diclofenac, Phenylbutazone and a Series of Sulfonamides on Hepatic Cytochrome P4502c Activity in Vitro, and Correlation with Some Molecular Descriptors in the Dwarf Goat (caprus hircus aegagrus). Xenobiotica, 27, 769-780. 

Four major MT isoforms, MT-1, MT-2, MT-3, and MT-4, have been identified in mammals. The most widely expressed isoforms in mammals, MT-1 and MT-2, are rapidly induced in the liver by a wide range of metals, drugs, and inflammatory mediators. In the gut and pancreas, MT responds mainly to Zn status. A brain isoform, MT-3, has a specific neuronal growth inhibitory activity, while MT-1 and MT-2 have more diverse functions related to their thiolate cluster structure. These include involvement in Zn homeostasis, protection against heavy metal (especially Cd) and oxidant damage, and metabolic regulation via Zn donation, sequestration, and/or redox control. A possible role for MT-4 is related to copper requirements in epithelial differentiating tissues. 

Crisi, G. M., Katz, I. R., Zucker, M. B., and Thorbecke, G. T. (1996). Induction of inhibitory activity for B cell differentiation in human CDS T cells with pokeweed mitogen, dimaprit, and cAMP upregulating agents countersuppressive effect of platelet factor 4. Cell. Immunol. 172, 205-216. 

Leary, A.G., Wong, G.G., Clark, S.C., Smith, A.G. and Ogawa, M. (1990) Leukemia inhibitory factor differentiation-inhibiting activity/human interleukin for DA cells augments proliferation of human hematopoietic stem cells. BloodlS 1960-1964. 

Ono, K. Nakane, H. Meng, Z.H. Ose, Y. Sakai, Y. Mizuno, M. Differential Inhibitory Effects of Various Herb Extracts on The Activities of Reverse Transcriptase and Various Deoxyribonucleic Acid (DNA) Polymerase. Chem. Pharm. Bull. 1989, 37, 1810-1812. 

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