Family-1 UDP glycosyltransferases in pear (Pyrus bretschneideri): Molecular identification, phylogenomic characterization and expression profiling during stone cell formation.

Stone cells are a characteristic trait of pear fruits, and excessive stone cell formation has a significant negative impact on the texture and flavour of the pulp. Lignin is one of the main components of stone cells. Family-1 uridine diphosphate-glycosyltransferases (UGTs) are responsible for the glycosylation modification of monolignols. However, information remains limited regarding the relationship between UGTs and stone cell formation. To address this problem, we identified 139 UGTs from the pear genome, which were distributed in 15 phylogenetic groups (A-M, O, and P). We also performed a collinearity analysis of UGTs among four Rosaceae plants (pear, peach, mei, and strawberry). Phylogenetic analysis suggested that 13 PbUGTs might be related to the glycosylation of monolignols. Analysis of expression patterns demonstrated that most putative monolignol glycosylation-related PbUGTs not only showed high expression levels in flowers and buds but were also induced by exogenous ABA, SA, and MeJA. In addition, the transcript level of Pbr005014.1 (named PbUGT72AJ2) was consistent with the changing trend of lignin content in pear fruit, and the transcript level was also higher in 'Dangshan Su' pear with higher lignin and stone cell contents. Subcellular localization results showed that PbUGT72AJ2 was located mainly in the cytomembrane and cytoplasm. Based on our study, PbUGT72AJ2 is considered to be a monolignol glycosylation-related UGT. Our results provide an important source for the identification of UGTs and a foundation for the future understanding and manipulation of lignin metabolism and stone cell formation in pear fruit.

Synthesis and biological evaluation of novel pyranochalcone derivatives as a new class of microtubule stabilizing agents.

Twenty-five novel pyranochalcone derivatives were synthesized and evaluated for their in vitro and in vivo antiproliferative activities. Among them, compound 10i exhibited superior potent activity against 21 tumor cell lines including multidrug resistant phenotype with the IC50 values ranged from 0.09 to 1.30 µM. In addition, 10i significantly induced cell cycle arrest in G2/M phase, promoted tubulin polymerization into microtubules and caused microtubule stabilization. Further studies confirmed that 10i significantly suppressed the growth of tumor volume in HepG2 xenograft tumor model. Our study demonstrated that 10i could have beneficial antitumor activity as a novel microtubule stabilizing agent.

Semi-synthesis and biological evaluation of 1,2,3-triazole-based podophyllotoxin congeners as potent antitumor agents inducing apoptosis in HepG2 cells.

A series of 4ß-[(4-substituted)-1,2,3-triazol-1-yl]podophyllotoxin congeners were synthesized by employing click chemistry and further evaluated for their antitumor activity by MTT assay. Among them, six congeners (10, 11, 12, 13, 22, and 24) exhibited approximately 100-fold more potent inhibitory activity against four tumor cell lines (HepG2, MKN-45, NCI-H1993, and B16) than etoposide as positive control. Docking studies on binding in the ATPase domain of topoisomerase II revealed perfect docking of four congeners in the active site. Furthermore, the podophyllotoxin congeners 10, 11, 12, and 13 induced cell cycle arrest of HepG2 cells at the G(2) /M phase in a concentration-dependent manner, assessed by flow cytometric analysis, highlighting that they exert their antitumor activity via HepG2 cell apoptosis.

Design, synthesis, and structure-activity relationship studies of novel millepachine derivatives as potent antiproliferative agents.

In this paper, 38 millepachine derivatives have been designed, synthesized and evaluated for their in vitro and in vivo antiproliferative activity. Among these novel derivatives, 15 displayed more potent antiproliferative activity than millepachine against HepG2, K562, SK-OV-3, HCT116, HT29, and SW620 tumor cells (mean IC(50) = 0.64 vs. 2.86 µM, respectively). Furthermore, 15 could effectively inhibit tubulin polymerization in HepG2 cells, and induce the HepG2 cell cycle arrest at the G2/M phase in a concentration-dependant manner. Further studies confirmed that 15 significantly suppressed the growth of tumor volume and exerted more potent anticancer potency than millepachine and anticancer drug cisplatin in A549 lung xenograft tumor model.

Rational design, synthesis, and pharmacological properties of pyranochalcone derivatives as potent anti-inflammatory agents.

24 derivatives (5a-x) derived from natural pyranochalcones (I and II) were designed and evaluated for their inhibitory potency on the production of nitric oxide (NO) in LPS-stimulated RAW264.7 cells. Among them, four compounds (5b, 5d, 5f, and 5h) exhibited more potent inhibitory effects on iNOS activity and iNOS-mediated NO production than a positive control indomethacin. Furthermore, 5b could significantly suppress the progression of carrageenan-induced hind paw edema compared to indomethacin at a dosage of 10 mg/kg/day, and dose-dependently ameliorated the development of adjuvant-induced arthritis (AIA) validated by arthritic scores and H&E staining of joints. In addition, docking study confirmed that 5b was an iNOS inhibitor with binding to the active site of murine iNOS.

Synthesis and antiangiogenic activity of novel gambogic acid derivatives.

Gambogic acid (GA) is in a phase II clinical trial as an antitumor and antiangiogenesis agent. In this study, 36 GA derivatives were synthesized and screened in a zebrafish model to evaluate their antiangiogenic activity and toxicity. Derivatives 4, 32, 35, 36 effectively suppressed the formation of newly grown blood vessels and showed lower toxicities than GA as evaluated by zebrafish heart rates and mortalities. They also exhibited more potent migration and HUVEC tube formation inhibiting activities than GA. Among them, 36 was the most potent one, suggesting that it may serve as a potential new antiangiogenesis candidate with low toxicity. Additionally, 36 showed comparable antiproliferative activity to HUVECs and five tumor cell lines but low cytotoxicity to LO2 cells.

Design, synthesis and biological evaluation of thiazole- and indole-based derivatives for the treatment of type II diabetes.

Present studies have shown that the lipid carrier has a significant role in several aspects of metabolic syndrome in A-FABP/ap2-deficient mice, including type 2 diabetes and atherosclerosis. 38 Thiazole- and indole-based derivatives were synthesized and investigated for their inhibitory effects on the production of LPS-stimulated TNF-α. Among them, 12b exhibited an excellent inhibitory efficiency compared to BMS309403 (95% vs. 85%) at the concentration of 10 µM and a binding affinity for ap2 with the apparent K(i) values 33 nM. Oral administration of 12b at a dosage of 50 mg/kg effectively reduced the levels of plasma blood glucose, triglycerides, insulin, total cholesterol and alanine aminotransferase in high-fat/diet-induced obesity model. The results highlighted that 12b was a potent anti-diabetic agent.

Synthesis and biological evaluation of novel dimethyl[1,1'-biphenyl]-2,2'-dicarboxylate derivatives containing thiazolidine-2,4-dione for the treatment of concanavalin A-induced acute liver injury of BALB/c mice.

In this paper, we reported the synthesis of bifendate derivatives and evaluation of anti-inflammatory activity by detecting the production of the Nitric Oxide (NO) in the lipopolysaccharide(LPS)-stimulated RAW 264.7 cell lines. Among the newly derivatives, compound 7k was the most potent one and two other compounds (7e and 7f) also exhibited greater anti-inflammatory activity than bifendate. Further in vivo studies confirmed that 7k significantly and dose-dependently inhibited carrageenan-induced paw edema and decreased the serum levels of alanine aminotransaminase, and aspartate aminotransaminase in concanavalin A-induced hepatitis model. Histopathological evaluation demonstrated that 7k has better hepatoprotective effect on acute liver injury induced by concanavalin A than bifendate, suggesting that 7k is a potential drug candidate for the treatment of hepatic injuries.