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551.
Jeong LS Lee HW Kim HO Jung JY Gao ZG Duong HT Rao S Jacobson KA Shin DH Lee JA Gunaga P Lee SK Jin DZ Chun MW Moon HR 《Bioorganic & medicinal chemistry》2006,14(14):4718-4730
A large series of N6-substituted-4'-thioadenosines were synthesized starting from D-gulonic-gamma-lactone, and structure-activity relationships were studied at the human A3 and other subtypes of adenosine receptors (ARs). 2-Chloro-substituted and 2-H analogues were compared. 2-Chloro-N6-methyl-4'-thioadenosine 19b was a highly potent and selective agonist (Ki=0.8+/-0.1 nM in binding) at the A3AR, and displayed the same relative efficacy in receptor activation as a known full agonist, Cl-IB-MECA. Most of N6-substituted-4'-thioadenosines were less potent in binding than the corresponding N6-substituted-adenosines or N6-substituted-4'-thioadenosine-5'-uronamides. N6-(3-Iodobenzyl) derivative 19g was demonstrated to be an A3AR-selective partial agonist displaying a Ki value of 3.2 nM. 相似文献
552.
Moon MJ Lee SK Lee JW Song WK Kim SW Kim JI Cho C Choi SJ Kim YC 《Bioorganic & medicinal chemistry》2006,14(1):237-246
Indirubin, an active ingredient of a traditional Chinese recipe Danggui Longhui Wan, has been known as a CDK inhibitor competing with ATP for binding to the catalytic site of cyclin-dependent kinases (CDKs). Since CDKs, a group of serine/threonine kinases forming active heterodimeric complexes with cyclins, are key regulators of the cell cycle regulation, therapeutic interventions targeting CDKs have been stimulated for the treatment of proliferative diseases, such as cancer, psoriasis, and for the prevention of chemotherapy-associated side effects, such as alopecia. A series of novel indirubin analogs was synthesized and evaluated for anti-proliferative and CDK2 inhibitory activities. Among the indirubin derivatives tested in the growth inhibitions against several human cancer cell lines, 5-nitro, halide, and bulky group containing acylamino substituted analogs showed high anti-proliferative effects. Selected analogs showing potent anti-proliferative activities were evaluated further in the CDK2 enzyme assay, which resulted in the discovery of potent CDK2 inhibitors. 相似文献
553.
554.
Su Hui Yang Hue Thi My Van Thanh Nguyen Le Daulat Bikram Khadka Suk Hee Cho Kyung-Tae Lee Hwa-Jin Chung Sang Kook Lee Chang-Ho Ahn Young Bok Lee Won-Jea Cho 《Bioorganic & medicinal chemistry letters》2010,20(17):5277-5281
In the search for potent water-soluble 3-arylisoquinolines, several 3-arylisoquinolinamines were designed and synthesized. Various substituted 3-arylisoquinolinamines exhibited strong cytotoxic activity against eight different human cancer cell lines. In particular, C-6 or C-7 dimethylamino-substituted 3-arylisoquinolinamines displayed stronger potency than the lead compound 7a. Interestingly, compounds 7b and 7c showed more effective activity against paclitaxel-resistant HCT-15 human colorectal cancer cell lines when compared to the original cytotoxic cancer drug, paclitaxel. We analyzed the cell cycle dynamics by flow cytometry and found that treatment of human HCT-15 cells with 3-arylisoquinolinamine 7b blocked or delayed the progression of cells from G0/G1 phase into S phase, and induced cell death. Treatment with compound 7b also significantly inhibited the growth of tumors and enhanced tumor regression in a paclitaxel-resistant HCT-15 xenograft model. 相似文献
555.
Young-Ok Son Ki-Choon Choi Jeong-Chae Lee Sung-Ho Kook Suk-Kyeong Lee Kenzo Takada Yong-Suk Jang 《Biochimica et Biophysica Acta (BBA)/General Subjects》2006
Taxol (paclitaxel) is one of the most potent antimicrotubule agents currently used in cancer chemoprevention and treatment. However, the effects of taxol on the induction of apoptosis in Epstein–Barr virus (EBV)-infected cells are unknown. This study investigated the mechanisms of taxol on cell cycle arrest and apoptosis induction using the EBV-infected cell line, Akata. Taxol treatment sensitively and dose-independently induced growth inhibition, cytotoxicity, and apoptosis in the cells, which was demonstrated by the decreased level of tritium incorporation and cell viability, the increased number of positively stained cells in the trypan blue staining and TUNEL assay, the increased population of cells in the sub-G0/G1 phase in flow cytometric analysis, and ladder formation of the genomic DNA. Treatment with z-VAD-fmk almost completely protected the cells from taxol-induced apoptosis indicating that the taxol-induced apoptosis of Akata cells is caspase-dependent. In addition, taxol-induced apoptosis is proposed to be associated with a lower mitochondrial membrane potential and G2/M arrest. However, the tubulin expression level doses not appear to be a direct mediator of taxol-induced apoptosis in cells. The presence of EBV in these cells was not related to the sensitivity of the cells to the induction of apoptosis by taxol. Overall, these results demonstrate that taxol induces apoptosis in EBV-infected Akata cells in a dose-independent manner, and that caspase activation and mitochondrial stress are involved in the induction. 相似文献
556.
557.
Biotic signaling molecules including abscisic acid (ABA) are involved in signal transduction pathways that mediate the defense
response of plants to environmental stresses. The antimicrobial protein gene CaAMP1, previously isolated from pepper (Capsicum annuum), was strongly induced in pepper leaves exposed to ABA, NaCl, drought, or low temperature. Because transformation is very
difficult in pepper, we overexpressed CaAMP1 in Arabidopsis. CaAMP1-overexpressing (OX) transgenic plants exhibited reduced sensitivity to ABA during the seed germination and seedling stages.
Overexpression of CaAMP1 conferred enhanced tolerance to high salinity and drought, accompanied by altered expression of the AtRD29A gene, which is correlated with ABA levels and environmental stresses. The transgenic plants were also highly tolerant to
osmotic stress caused by high concentrations of mannitol. Together, these results suggest that overexpression of the CaAMP1 transgene modulates salt and drought tolerance in Arabidopsis through ABA-mediated cell signaling.
The nucleotide sequence data reported here have been deposited in the GenBank database under the accession number AY548741. 相似文献
558.
559.
Jung Ha Kim Kabsun Kim Hye Mi Jin Insun Song Bang Ung Youn Junwon Lee Nacksung Kim 《Molecules and cells》2009,28(3):201-207
Silibinin is a polyphenolic flavonoid compound isolated from milk thistle (Silybum marianum), with known hepatoprotective, anticarcinogenic, and antioxidant effects. Herein, we show that silibinin inhibits receptor
activator of NF-κB ligand (RANKL)-induced osteoclastogenesis from RAW264.7 cells as well as from bone marrow-derived monocyte/macrophage
cells in a dose-dependent manner. Silibinin has no effect on the expression of RANKL or the soluble RANKL decoy receptor osteoprotegerin
(OPG) in osteoblasts. However, we demonstrate that silibinin can block the activation of NF-κB, c-Jun N-terminal kinase (JNK),
p38 mitogen-activated protein (MAP) kinase, and extracellular signal-regulated kinase (ERK) in osteoclast precursors in response
to RANKL. Furthermore, silibinin attenuates the induction of nuclear factor of activated T cells (NFAT) c1 and osteoclast-associated
receptor (OSCAR) expression during RANKL-induced osteoclastogenesis. We demonstrate that silibinin can inhibit TNF-α-induced
osteoclastogenesis as well as the expression of NFATc1 and OSCAR. Taken together, our results indicate that silibinin has
the potential to inhibit osteoclast formation by attenuating the downstream signaling cascades associated with RANKL and TNF-α. 相似文献
560.
Yoon-Ah Kook Sun-Kyung Lee Dae-Hyung Son Kyung-Hwa Kang Sang-Cheol Kim Hwa-Jeong Lee Eun-Cheol Kim 《Cell biology international》2009,33(3):424-428
Although substance P (SP) is associated with osteoclast differentiation and bone resorption, little is known about the osteogenic differentiation-inducing effects of SP in periodontal ligament (PDL) cells. This study investigated whether PDL cells could differentiate into osteoblastic-like cells by SP. The expression of osteoblastic differentiation markers such as osteopontin (OPN), osteonectin (ON), osteocalcin (OCN) and bone sialoprotein (BSP) were evaulated by Western blotting. Additionally, SP-mediated heme oxygenase-1 (HO-1) pathways were further clarified.SP increased HO-1 and osteogenic differentiation in concentration- and time-dependent manners, as determined by OPN, ON, OCN and BSP expression. Furthermore, treatment with inhibitors of p38, ERK MAPK, and NF-κB abolished SP-induced osteogenic differentiation and HO-1 expression. SP-induced translocation of Nrf-2 was also observed. The combined results suggest that SP activates the stress-response enzymes HO-1 and Nrf-2, subsequently leading to upregulation of osteogenic differentiation in human PDL cells. 相似文献