Original Article

Journal of Investigative Dermatology (1996) 107, 229–234; doi:10.1111/1523-1747.ep12329697

In the Absence of Streptomycin, Minoxidil Potentiates the Mitogenic Effects of Fetal Calf Serum, Insulin-Like Growth Factor 1, and Platelet-Derived Growth Factor on NIH 3T3 Fibroblasts in a K + Channel-Dependent Fashion

Deborah A Sanders, Ian Fiddes1, Darren M Thompson, Michael P Philpott, Gillian E Westgate2 and Terence Kealey

  1. Department of Clinical Biochemistry, University of Cambridge, Addenbrookes Hospital, Hills Road, Cambridge, CB2 2QR, U.K.
  2. 1Department of Biological Sciences, Anglia Polytechnic University, East Road, Cambridge, CB1 1PT, U.K.
  3. 2Unilever Research, Colworth House, Sharnbrook, Bedford, MK44 1LQ, U.K.

Received 18 December 1995; Revised 21 March 1996; Accepted 10 April 1996.

Top

Abstract

There is considerable evidence to suggest that the opening of K+ channels plays an important role in stimulating mitogenesis. K+ channel blockers have been shown to inhibit mitogenesis in vitro, mitogens increase cytosolic membrane K+ channel permeability, K+ channel openers stimulate hair growth in vivo, and the Ras/Raf signal transduction pathway induces K+ channel activity. Paradoxically, however, K+ channel openers such as minoxidil have been reported in vitro not to modulate, or even to inhibit, mitogenesis in a range of cell types. Only untherapeutic concentrations have stimulated mitogenesis. These experiments, however, appear to have been carried out in the presence of aminoglycoside antibiotics, which inhibit potassium channel activity. We now report that in the absence of aminoglycoside antibiotics, minoxidil at 10 mug/ml (0.05 mM) causes a significant stimulation of proliferation of NIH 3T3 fibroblasts maintained over a 10-d period in 5% fetal calf serum-supplemented medium. Further, we show that in the presence of 100 mug streptomycin per ml, minoxidil at 10 mug/ml produces an initial inhibition of proliferation, which apparently confirms, in NIH 3T3 fibroblasts, that the inhibition of mitogenesis by minoxidil in the presence of streptomycin is an artifact. The potentiation of NIH 3T3 cell growth by minoxidil can be attributed to the opening of potassium channels, because the potassium channel blocker tolbutamide (5 mM) or combinations of the blockers tolbutamide (1 mM)/tetraethylammonium (2 mM) or glibenclamide (1 muM)/apamin (10 nM) block the minoxidil-induced stimulation of growth. We also demonstrate that minoxidil is able to significantly potentiate the mitogenic effects of both platelet-derived growth factor and insulin-like growth factor 1 on NIH 3T3 fibroblasts in the presence of CPSR-2 (a cytokine free serum substitute). Thus we have shown that minoxidil potentiates the mitogenic effects of fetal calf serum in vitro on NIH 3T3 fibroblasts by opening potassium channels and is also able to potentiate the mitogenic effects of the growth factors platelet-derived growth factor and insulin-like growth factor 1.

Keywords:

IGF-1, K+ channels, minoxidil, mitogenesis, NIH 3T3 fibroblasts, PDGF

Top

References

  1. Arcangoli, A, Carla, M, del, Bene MP, Beccdhetti, A, Wanke, E, Olivotta, M: Polar/apolar compounds induce leukemia cell differentiation by modulating cell-surface potential. Proc Natl Acad Sci USA 90: 5858–5862, 1993
  2. Baden, HP, Kubilus, J: Effects of minoxidil on cultured kerntimocytes. J Invest Dermatol 81: 558–560, 1983
  3. Becchetti, A, Arcangeli, A, del Bene, MR, Olivotta, M, Wanke, E: Response to fibronection-integrin interaction in leukaetnia cells: delayed enhancing of a K1 current. Proc R Soc Lond /Biolf 248: 235–240, 1992
  4. Bernd, A, Breuer, M, Dold, K, Holzmann, H: Uptake kinetics and effect of minoxidil on human keratinocyte cultures. Arzneimaittelforschang 40: 413–416, 1990
  5. Bourne, HR: Signal transduction: team blue sees red. Nature 376: 727–729, 1995 | Article | PubMed | ISI | ChemPort |
  6. Buhl, AE, Waldon, DJ, Baker, CA, Johnson, GA: Minoxidil sulfate is the active metabolite that stemulates hair follicles. J Invest Dermatol 95: 553–557, 1990 | Article | PubMed | ISI | ChemPort |
  7. Buhl, AE, Waldon, DJ, Conrad, SJ, Mulholland, MJ, Shull, KL, Kubicek, MF, Johnson, GA, Brunden, MN, Stefanski, KJ, Stehle, RG, Gadwood, RC, Kamdar, BV, Thomasco, LM, Schostaraez, HJ, Schwartz, TM, Diani, AR: Potassium channel conductance: A mechanism affecting hair growth both in vitro and vivo. J Invest Dermatol 98: 315–319, 1992 | Article | PubMed | ISI | ChemPort |
  8. Cohen, RL, Alves, ME, Weiss, VC, West, DP, Chambers, DA: Direct effects of minoxidil on epidermal cells in culture. J Invest Dermatol 82: 90–93, 1984
  9. Cook, NS: The pharmacology of potassium channels and their therapetitic potential. Trends Pharmacol Sci 9: 21–28, 1988 | Article | PubMed | ChemPort |
  10. Dargie, HJ, Dollery, CT, Daniel, J: Minoxidil in resitant hypertension. Lancet 2: 515–518, 1977
  11. Deutsch, C: K1 channels and mitogenesis. In: Colatsky T (ed.). Potassium Channels: Basic Function adn Therapents Aspects Wiley Liss, New York, pp 251–271, 1990
  12. Dubois, J-M, Rouzaire-Dobois, B: Role of potassium channels in mitogenesia. Prog Biophys Alol Biol 59: 1–21, 1993
  13. Harmon, CS, Lutz, D, Ducote, J: Potassiu channels openers stimulate DNA synthesis in mouse epidermal keratinoeyte and whole hair follicle cultures. Skin Pharmacol 6: 170–178, 1993 | PubMed | ISI | ChemPort |
  14. Harmon, CS, Nevius, TD: II-lalpha inhibits human hair follicle growth and hair fiber formation in whole-orgen cultures. Lymphokine Cytoklne Res 12: 197–203, 1993
  15. Harrington, EA, Bennett, MR, Fanidi, A, Even, GI: e-Mye-induced apoptosis in fibroblasts in inhibited by specitic cytokines. EMBO J 13: 3286–3295, 1994 | PubMed | ISI | ChemPort |
  16. Headington, JT, Novak, E: Clinical and histological studies of male pattern baldness trented with topical minoxidil. Carr Ther Res 36: 1098–1106, 1984
  17. Haung, Y, Rane, SG: Potassium channel induction by the Rax/Raf signal transduction enscade. J Biol Chem 269: 31183–31189, 1994
  18. Katsuok, K, Schell, H, Wessel, B, Horstein, OP: The effects of epidermal growth factor, fibroblast growth factor, minoxidil and hydrocortisone on growth kinetics in human hair bulb papilla cells and root sheath fibroblasts cultured in vitro. Arch Dermatol Res 279: 247–250, 1987
  19. Lev, S, Moreno, H, Martinez, R, Canoll, P, Peles, E, Musaeehio, JM, Plowman, GD, Rudy, B, Schlessinger, J: Protein tyrosine kinase PYK2 involved in Ca2+-induced regulaltion of ion channel and MAP kinase functions. Nature 376: 737–745, 1995 | Article | PubMed | ISI | ChemPort |
  20. Meisheri, KD, Cipkus, LA, Taylor, CJ: Meehanism of action of minoxidil sultfate-induced vasodilation: a role for increased K permanbility. J Pharuscol Exp Ther 245: 751–760, 1988
  21. Moore, GPM, Pnnaretto, BA, Rohertson, D: Effects of epidermal growth factor on hair growth in the mouse. J Endocrinol 88: 293–299, 1981 | PubMed | ISI | ChemPort |
  22. Murad, S, Pinnell, SR: Suppression of fibroblast proliferation and lysyl hydroxylse activity by minoxidil. J Biol Chem 262: 11973–11978, 1987
  23. Nilius, B, Drnoogmans, G: A roel for K+ channels in cell proliferation. NIPS 9: 105–110, 1994
  24. Normura, K, Narose, K, Watanabe, K, Sokabe, M: Aminoglycoside blockage of Ca21-activate K1 channel from rat brain synaptosomal membranes incorporated into planar bilayers. J Membr Biol 115: 241–251, 1990
  25. Norris, WD, Johnson, G, Donald, GS: The effect of minoxidil on endothelial cells in vitro. Cell Blol Int Rep 13: 555–562, 1989
  26. Ohtsuyama, M, Sato, F, Toyomoto, T, Sato, K: Stimulation of Cl conductance by minoxidil sulfate and K conductance by minoxidil in eccrine clear cells. J Pharmacol Exp Ther 269: 823–831, 1994
  27. O'Keefe, E, Payne, RE: Minoxidil: inhibition of proliferation of keratinoeytes in vitro. J Invest Dermatol 97: 534–536, 1991
  28. Oosawa, Y, Sokabe, M: Voltage-dependent aminoglycoside blockage of the sarcoplaxmic reticulum K' channel. Am J Physiol 250: 361–364, 1986
  29. Peters, KG, Werner, S, Chen, G, Williams, LT: Two FGF receptor genes are differentially expressed in epithelial and mesenchymal tissues during limb formation and organogenesis in the mouse. Development 114: 233–243, 1992 | PubMed | ISI | ChemPort |
  30. Philpott, MP, Kealey, T: Effects of EGF on the morphology and patterns of DNA synthesis in isolated human hair follicles. J Invest Dermatol 102: 186–191, 1994 | Article | PubMed | ISI | ChemPort |
  31. Philpott, MP, Sanders, DA, Kealey, T: Effects of insulin and insulin-like growth factors on cultured human hair follicles: IGF-1 at physiologic concentrations in an important regulator of hair follicle growth in vitro. J Invest Dermatol 102: 857–861, 1994 | Article | PubMed | ISI | ChemPort |
  32. Philpott, MP, Sanders, DA, Kealey, T: Cultured humah hair follicles and growth factors. J Invest Dermatol 104: 44–45, 1995
  33. Pietrzkowki, Z, Sell, C, Lammers, R, Ullrich, A, Baserga, R: Roles of insulin like growth factor 1 (IGf-1) and the IGF-1 receptor in epidermal growth factoro-stinmulated growth of 3T3 cells. Mol Cell Biol 12: 3883–3889, 1992
  34. Ponten, F, Ren, Z, Nister, M, Westermark, B, Ponten, J: Epithelial-stromal interactions in basal cell cancer: the PDGF system. J Invest Dermatol 102: 304–309, 1994 | Article | PubMed | ISI | ChemPort |
  35. Priestley, GC, Lord, R, Stavropoulous, P: The metabolism of fibroblasts from normal and fibrotie skin is inbibited by minoxidil in vitro. Br J Dermatol 125: 217–221, 1991
  36. Quast, U, Cook, NS: Moving together: K' channel openers and ATP-sensitive K channels. Trends Pharmatol Sci 10: 431–434, 1989
  37. Rook, AJ, Dawber, RPR: Disceses of the Hair and Scalp 2nd ed. Blackwell Scientitic, Oxford, p 275, 1994
  38. Roos, R, Raines, RW, Bowen-Pope, DF: The biology of platelet-derived growth factor. Cell 46: 155–169, 1986
  39. Stiles, CD, Capone, GT, Scher, CD, Antoniades, NII, Van, Wyk JJ, Pledger, WJ: Dual control of cell control by somatomedins and platelet-derived growth factor. Prov Natl Acad Sci USA 76: 1279–1283, 1979
  40. Takeuchi, S, Wangemann, P: Aminoglycoside antibiotics inhibit maxi-K' channel in single isolated cochlear efferent nerve teminals. Hearing Res 67: 13–19, 1993
  41. Tanigaki-Oban, N, Ito, M: Effects of cepharanthine and minoxidil on proliteration differentiation and keratinization of cultured cells from the murine hair apparatus. Arch Dermatol Res 284: 290–296, 1992
  42. Tsein, RW, Txien, RT: Calcium channels, stores, and oseillations. Amun Rev Cell Biol 6: 715–760, 1990
  43. Wickenden, AD, Grimwood, S, Grant, TL, Todd, MII: Comparison of the effects of the K1-channel openers cromakalin and minosidil sulphate on vasecular smooth muscle. Br J Pharmacol 103: 1148–1152, 1991

Extra navigation

.
ADVERTISEMENT