Transcriptional profiling in human HaCaT keratinocytes in response to kaempferol and identification of potential transcription factors for regulating differential gene expression.
Kaempferol is the major flavonol in green tea and exhibits many biomedically useful properties such as antioxidative, cytoprotective and anti-apoptotic activities. To elucidate its effects on the skin, we investigated the transcriptional profiles of kaempferol-treated HaCaT cells using cDNA microarray analysis and identified 147 transcripts that exhibited significant changes in expression. Of these, 18 were up-regulated and 129 were down-regulated. These transcripts were then classified into 12 categories according to their functional roles: cell adhesion/cytoskeleton, cell cycle, redox homeostasis, immune/defense responses, metabolism, protein biosynthesis/modification, intracellular transport, RNA processing, DNA modification/ replication, regulation of transcription, signal transduction and transport. We then analyzed the promoter sequences of differentially-regulated genes and identified over-represented regulatory sites and candidate transcription factors (TFs) for gene regulation by kaempferol. These included c-REL, SAP-1, Ahr-ARNT, Nrf-2, Elk-1, SPI-B, NF-kappaB and p65. In addition, we validated the microarray results and promoter analyses using conventional methods such as real-time PCR and ELISA-based transcription factor assay. Our microarray analysis has provided useful information for determining the genetic regulatory network affected by kaempferol, and this approach will be useful for elucidating gene-phytochemical interactions.
Kang
Byung Young
BY
School of Chemical and Biological Engineering, Seoul National University, Seoul 151-742, Korea.
Kim
Sujong
S
Lee
Ki-Hwan
KH
Lee
Yong Sung
YS
Hong
Il
I
Lee
Mi-Ock
MO
Min
Daejin
D
Chang
Ihseop
I
Hwang
Jae Sung
JS
Park
Jun Seong
JS
Kim
Duck Hee
DH
Kim
Byung-gee
BG
D001483:Base Sequence; D002460:Cell Line; D017931:DNA Primers; D004797:Enzyme-Linked Immunosorbent Assay; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D044949:Kaempferols / Q000494:pharmacology*; D015603:Keratinocytes / Q000187:drug effects* / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D011401:Promoter Regions, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000502:physiology*; D014158:Transcription, Genetic / Q000187:drug effects*
D017931:DNA Primers; D044949:Kaempferols; D014157:Transcription Factors; C006552:kaempferol