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Zong-Ru Guo

Publications and source records attributed to Zong-Ru Guo.

7 recordsLinked to original sources
PubMed2006

Synthesis and anti-diabetic activity of (RS)-2-ethoxy-3-{4-[2-(4-trifluoro-methanesulfonyloxy-phenyl)-ethoxy]-phenyl}-propionic acid.

AIM: To synthesize and study the anti-diabetic activity of (RS)-2-ethoxy-3-{4-[2-(4-trifluoromethanesulfonyloxy-phenyl)-ethoxy]-phenyl}-propionic acid (compound I). METHODS: Compound I was prepared in 6 steps, using 4-(2-hydroxy-ethyl)-phenol as the starting material. The in vitro selectivity and potency of target compound I, rosiglitazone and WY-14643 on human PPARalpha and PPARgamma were determined in reporter gene assays. In vivo, rosiglitazone and compound I were administered orally to KK(Ay) mice for 14 d. Insulin tolerance tests and oral glucose tolerance tests were performed on the 10th and 14th day of treatment, respectively. At the end of the treatment, sera were collected for biochemical analysis. RESULTS: In vitro, compound I significantly activated both PPARalpha and PPARgamma. In vivo, compound I corrected the impaired insulin and glucose tolerance of KK(Ay) mice, and produced a significant reduction in plasma triglyceride levels after 14 d of treatment. The effect produced was significant compared with the control group. CONCLUSION: Both in vitro and in vivo anti-diabetic activity studies for compound I were conducted and the data suggest that this compound is a potentially effective anti-diabetic agent.

Animals↗
PubMed2006

Formation of 4'-carboxyl acid metabolite of imrecoxib by rat liver microsomes.

AIM: Imrecoxib is a novel and moderately selective COX-2 inhibitor. The aim of the present in vitro investigation was to study the formation of the major metabolite 4'-carboxylic acid imrecoxib (M2) and identify the enzyme(s) involved in the reaction. METHODS: The formation of M2 was studied in rat liver cytosol in the absence or presence of liver microsome. The formed metabolite was identified and quantified by LC/MS(n). In addition, to characterize the cytochrome P450 (CYP) isozymes involved in M2 formation, the effects of typical CYP inhibitors (such as ketoconazle, quinine, alpha-naphthoflavone, methylpyrazole, and cimetidine) on the formation rate of M2 were investigated. RESULTS: The formation of M2 from 4-hydroxymethyl imrecoxib (M4) was completely dependent on rat liver microsomes and NADPH. Enzyme kinetic studies demonstrated that the formation rate of M2 conformed to monophasic Michaelis-Menten kinetics. Additional experiments showed that the formation of M2 was induced significantly by dexamethasone and lowered by ketoconazole strongly and concentration-dependently. By comparison, other CYP inhibitors, such as alpha-naphthoflavone, cimetidine, quinine, and methylpyrazole had no inhibitory effects on this metabolic pathway. CONCLUSION: These biotransformation studies of imrecoxib in rat liver at the subcellular level showed that the formation of M2 occurs in rat liver microsomes and is NADPH-dependent. The reaction was mainly catalyzed by CYP 3A in untreated rats and in dexamethasone-induced rats. Other CYP, such as CYP 1A, 2C, 2D, and 2E, seem unlikely to participate in this metabolic pathway.

Animals↗
PubMed2002

Molecular simulation of interaction between estrogen receptor and selective estrogen receptor modulators.

AIM: To study the mechanism of interaction between a series of potent racemic selective estrogen receptor modulators (SERM) and estrogen receptors (ER). METHODS: Active conformations of these conformationally restricted raloxifene analogues in binding pocket were determined by molecular mechanics. The interactive energies between ligand and receptor were calculated by docking program. RESULTS: Both R and S configurations of these SERM were accommodated by the binding pocket of ER. The hydroxy group of compounds forms hydrogen bonds with amino acid residues of ER and the phenolic group mimics the A ring of estradiol. The most potential compounds were those with two hydroxy groups and accommodated by binding pocket in S configuration with phenolic group at C(16) imitating A ring of estradiol. CONCLUSION: Chiral center conferred little effect on the binding affinity of these conformationally restricted raloxifene analogues. The hydroxy group(s) play(s) a critical role to the orientation of compounds in active pocket of ER and the binding between ligand and receptor.

Binding Sites↗
PubMed2002

Inhibitory effect of 3,4-diaryl-3-pyrrolin-2-one derivatives on cyclooxygenase 1 and 2 in murine peritoneal macrophages.

AIM: To develop a whole-cell assay based on murine peritoneal macrophages and evaluate the inhibitory effect of candidate compounds on cyclooxygenase-1 (COX-1) and COX-2. METHODS: Macrophages were stimulated with calcimycin or lipopolysaccharide (LPS) for various periods. Their abilities to convert endogenous arachidonic acid to 6-keto-PGF1alpha or PGE2 were examined by radioimmunoassay (RIA). RNA level of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and COX-1/2 was detected by reverse transcription polymerase chain reaction (RT-PCR) using specific primers. RESULTS: Rofecoxib selectively inhibited LPS-induced, COX-2-derived PGE2 synthesis with an IC50 value of (4.7+/-0.5) nmol/L compared with maximum inhibitory ratio of 17.3 % for the inhibition of calcimycin induced, COX-1-derived 6-keto-PGF1alpha synthesis. Indomethacin exhibited dual inhibitory effects on COX-1 and COX-2 with IC50 of (4.7+/-1.1) nmol/L and (7.1+/-1.2) nmol/L, respectively. Two series of 17 compounds were tested. Most of compounds in series II showed comparable inhibitory activities to rofecoxib on COX-2. The relative position of the sulfonylphenyl group to the lactam carbonyl group has important effects on COX-2 inhibitory activity. CONCLUSION: The established whole cell assay is appropriate for drug-design oriented in vitro assay. 3,4-Diaryl-3-pyrrolin-2-one derivatives were proved to be prospective new type of COX-2 selective inhibitors.

Animals↗
PubMed2001

[New Retinoid SX-116 Induces Apoptosis of Acute Promyelocytic Leukemia Cell Line NB4]

In this research, the effect of novel retinoid SX-116 on acute promyelocytic leukemia cell line NB4 was studied in vitro. Cell proliferation, cell morphological characters, flow cytometry, DNA electrophoresis and RT-PCR were observational parameters. The results showed that treated with SX-116 at 10(-6) mol/L, the growth and survival of NB4 cells were markedly inhibited, morphological changes of apoptosis, including membrane blebbing, chromosome condensation and fragmentation of nuclei were observed in NB4 cells after 24 hours exposure of SX-116. Further studies showed "DNA ladder" in genomic DNA electrophoresis, as well as a typical apoptotic peak below G(1) phase presented in flow cytometry. The expression of apoptosis - related gene bcl-2 and p53 were examined. The level of bcl-2 mRNA was downregulated by 6-hour treatment of SX-116, while the gene restored to the normal level by following 12-, 24- and 48-hour exposure. However, p53 mRNA was unchanged during the treatment. The results demonstrated that SX-116 could induce apoptosis of NB4 cells while the mechanism remains to be studied.

Journal Article↗