TY - JOUR
T1 - Biphasic effect of 1,25‐dihydroxyvitamin D3 on primary mouse epidermal keratinocyte proliferation
AU - Bollag, Wendy B.
AU - Ducote, Janet
AU - Harmon, Charles S.
PY - 1995/5
Y1 - 1995/5
N2 - 1,25‐Dihydroxyvitamin D3 [1,25(OH)2D3] has been proposed as a physiologic regulator of keratinocyte growth and differentiation. Utilizing a proliferative serum‐free culture system, we have found that at physiologic (picomolar) concentrations this hormone stimulated proliferation of primary mouse epidermal keratinocytes; at higher (nanomolar to micromolar) doses, growth was inhibited by 1,25(OH)2D3. We investigated the nature of the signal transduction mechanism underlying the response to 1,25(OH)2D3 and observed little or no effect of either low or high concentrations of the hormone on cytosolic calcium levels or Fos expression. Furthermore, the protein kinase C inhibitor, Ro 31‐7549, had very little effect on the growth inhibition induced by a high dose (1 μM) of 1,25(OH)2D3. This lack of rapid signal transduction events was consistent with the inability of a short (4‐hour) exposure to 1,25(OH)2D3 to initiate a complete growth‐inhibitory response as measured using [3H]thymidine incorporation. Our results indicate that physiologic concentrations of 1,25(OH)2D3 are required for optimal keratinocyte growth. Furthermore, we found no evidence of rapid effects of 1,25(OH)2D3 and suggest that in mouse epidermal keratinocytes, the response to this hormone is mediated by a slow transduction pathway, such as that activated by the intracellular 1,25(OH)2D3 receptor (VDR). © 1995 Wiley‐Liss, Inc.
AB - 1,25‐Dihydroxyvitamin D3 [1,25(OH)2D3] has been proposed as a physiologic regulator of keratinocyte growth and differentiation. Utilizing a proliferative serum‐free culture system, we have found that at physiologic (picomolar) concentrations this hormone stimulated proliferation of primary mouse epidermal keratinocytes; at higher (nanomolar to micromolar) doses, growth was inhibited by 1,25(OH)2D3. We investigated the nature of the signal transduction mechanism underlying the response to 1,25(OH)2D3 and observed little or no effect of either low or high concentrations of the hormone on cytosolic calcium levels or Fos expression. Furthermore, the protein kinase C inhibitor, Ro 31‐7549, had very little effect on the growth inhibition induced by a high dose (1 μM) of 1,25(OH)2D3. This lack of rapid signal transduction events was consistent with the inability of a short (4‐hour) exposure to 1,25(OH)2D3 to initiate a complete growth‐inhibitory response as measured using [3H]thymidine incorporation. Our results indicate that physiologic concentrations of 1,25(OH)2D3 are required for optimal keratinocyte growth. Furthermore, we found no evidence of rapid effects of 1,25(OH)2D3 and suggest that in mouse epidermal keratinocytes, the response to this hormone is mediated by a slow transduction pathway, such as that activated by the intracellular 1,25(OH)2D3 receptor (VDR). © 1995 Wiley‐Liss, Inc.
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U2 - 10.1002/jcp.1041630205
DO - 10.1002/jcp.1041630205
M3 - Article
C2 - 7706369
AN - SCOPUS:0028906229
SN - 0021-9541
VL - 163
SP - 248
EP - 256
JO - Journal of Cellular Physiology
JF - Journal of Cellular Physiology
IS - 2
ER -