• Title/Summary/Keyword: CDK inhibitor

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Anti-adipogenic Activity of Cortex ulmi pumilae Extract in 3T3-L1 Preadipocytes (유근피 추출물의 3T3-L1지방전구세포의 분화 억제 효능에 관한 연구)

  • Jeong, Hyun Young;Jin, Soojung;Nam, Soo Wan;Hyun, Sook Kyung;Kim, Sung Gu;Kim, Byung Woo;Kwon, Hyun Ju
    • Journal of Life Science
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    • v.24 no.2
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    • pp.137-147
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    • 2014
  • Cortex ulmi pumilae, the cortex of Ulmus davidiana var. japonica, has been used in traditional folk medicine for its anti-inflammatory effect. Although its various bioactivities such as anti-inflammatory, anti-microbial, and anti-cancer, have been reported, the anti-adipogenic activity of cortex ulmi pumilae remains unclarified. In the present study, we investigated the effect of cortex ulmi pumilae extract on adipocyte differentiation in 3T3-L1 preadipocytes. Treatment with cortex ulmi pumilae extract significantly reduced the formation of lipid droplets and triglyceride content in a dose-dependent manner; this is associated with an inhibition of the adipogenic transcription factors, CCAAT/enhancer binding protein ${\alpha}$ ($C/EBP{\alpha}$), $C/EBP{\beta}$, and peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$). In addition, cortex ulmi pumilae extract treatment during the early stage of adipogenesis showed more efficient anti-adipogenic activity than treatment during other stages of adipogenesis. Cortex ulmi pumilae extract also inhibited cell proliferation and induced G1 arrest of 3T3-L1 cells in the early stage of adipogenesis. This was associated with upregulated expression of Cdk inhibitor p21 and downregulated expression of cyclin E and phospho-Rb, indicating that cortex ulmi pumilae extract blocks mitotic clonal expansion by cell cycle regulation. Taken together, these results suggest that cortex ulmi pumilae extract possesses anti-adipogenic activity through the inhibition of adipocyte differentiation by blocking mitotic clonal expansion.

Effect of Nardostachyos Rhizoma on Apoptosis, Differentiation and Proliferation in HL-60 cells

  • Ju Sung-Min;Lee Jun;Choi Ho-Seung;Yoon Sang-Hak;Kim Sung-Hoon;Jeon Byung-Hun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.20 no.1
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    • pp.163-170
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    • 2006
  • Nardostachyos Rhizoma (N. Rhizoma) belonging to the family Valerianaceae has been anti-arrhythmic effect, and sedation to the central nerve and a smooth muscle. We reported that the water extract of N. Rhizoma induced apoptotic cell death and differentiation in human promyelocytic leukemia (HL-60) cells. Cytotoxicity of N. Rhizoma was detected only in HL-60 cells (IC50 is about 200 ${\mu}g/ml$). The cytotoxic activity of N. Rhizoma in HL-60 cells was increased in a dose-dependent manner. We used several measures of apoptosis to determine whether these processes were involved in N. Rhizoma-induced apoptotic cell death. The high-dose (200 ${\mu}g/ml$) treatment of N. Rhizoma to HL-60 cells showed cell shrinkage, cell membrane blobbing, apoptotic bodies, and the fragmentation of DNA, suggesting that these cells underwent apoptosis. Treatment of HL-60 cells with N. Rhizoma time-dependently induced activation of caspase-3, caspase-8, and caspase-9 and proteolytic cleavage of poly(ADP-ribose) polymerase. Also, we investigated the effect of N. Rhizoma on cellular differentiation and proliferation in HL-60 cells. Differentiation and proliferation of HL-60 cells was determined through expression of CD11b and CD14 surface antigens using flow cytometry and nitroblue tetrazolium (NBT) assay, and through analysis of cell cycle using propidium iodide assay, respectively. N. Rhizoma induced the differentiation of HL-60 at the low-dose (100 ${\mu}g/ml$) treatment, as shown by increased expression of differentiation surface antigen CD11b, but not CDl4 and increased reducing activity of NBT. When HL-60 cells were treated with N. Rhizoma at concentration of $50{\mu}g/ml\;and\;100{\mu}g/ml$, NBT-reducing activities induced approximately 1.5-fold and 20.0-fold as compared with the control. In contrast, HL-60 cells treated with the N. Rhizoma-ATRA combination showed markedly elevated levels of 26.3-fold at $50{\mu}g/ml$ N. Rhizoma-0.1 ${\mu}M$ ATRA combination and 27.5-fold at 50 ${\mu}g/ml$ N. Rhizoma-0.2 ${\mu}M$ ATRA combination than when treated with N. Rhizoma alone or ATRA alone. It may be that N. Rhizoma plays important roles in synergy with ATRA during differentiation of HL-60 cells. DNA flow-cytometry indicated that N. Rhizoma markedly induced a G1 phase arrest of HL-60 cells. N. Rhizoma-treated HL-60 cells increased the cell population in G1 phase from 32.71% to 42.26%, whereas cell population in G2/M and S phases decreased from 23.61% to 10.33% and from 37.78% to 33.98%, respectively. We examined the change in the $p21^{WAF1/Cip1}\;and\;p27^{Kip1}$ proteins, which are the CKIs related with the G1 phase arrest. The expression of the CDK inhibitor $p27^{Kip1},\;but\;not\;p21^{WAF1/Cip1}$ were markedly increased by N. Rhizoma. Taken together, these results demonstrated that N. Rhizoma induces apoptotic cell death through activation of caspase-3, and potently inhibits the proliferation of HL-60 cells via the G1 phase cell cycle arrest in association with $p27^{Kip1}$ and granulocytic differentiation induction .