[Advances in microbial whole-cell sensors for the detection of aromatic compounds].

The inherent stability and recalcitrance of benzene ring structures render aromatic compounds a major ecological concern and a substantial risk to human health. Hence, developing a facile and efficacious detection technique for aromatic compounds is essential. As our comprehension of aromatic compound characteristics deepens, microbial cell-based biosensors have emerged as increasingly popular tools in the detection of aromatic compounds. This article introduces the operational principles of microbial whole-cell biosensors and elucidates the construction techniques and applications of electroactive biofilm-based microbial whole-cell sensors, transcription factor-based microbial whole-cell sensors, and degradation gene promoter-dependent microbial whole-cell sensors in the detection of aromatic compounds. In addition, we review the methodologies for improving the performance of microbial whole-cell sensors based on surface display, logic gate construction, genetic circuit modification, and quorum sensing signal amplification.

Dorzagliatin (HMS5552), a novel dual-acting glucokinase activator, improves glycaemic control and pancreatic ß-cell function in patients with type 2 diabetes: A 28-day treatment study using biomarker-guided patient selection.

AIMS: To investigate the pharmacokinetics and pharmacodynamics of a dual-acting glucokinase activator, dorzagliatin, and its safety, tolerability and effect on pancreatic ß-cell function in Chinese patients with type 2 diabetes (T2D). MATERIALS AND METHODS: A total of 24 T2D patients were selected, utilizing a set of predefined clinical biomarkers, and were randomized to receive dorzagliatin 75 mg twice or once daily (BID, QD respectively) for 28 days. Changes in HbA1c and glycaemic parameters from baseline to Day 28 were assessed. In addition, changes in ß-cell function from baseline to Day 32 were evaluated. RESULTS: Significant reductions in HbA1c were observed in both regimens on Day 28 (-0.79%, 75 mg BID; -1.22%, 75 mg QD). Similar trends were found in the following parameters, including reductions from baseline in fasting plasma glucose by 1.20 mmol/L and 1.51 mmol/L, in 2-hour postprandial glucose by 2.48 mmol/L and 5.03 mmol/L, and in glucose AUC0-24 by 18.59% and 20.98%, for the BID and QD groups, respectively. Both regimens resulted in improvement in ß-cell function as measured by steady state HOMA 2 parameter, %B, which increased by 36.31% and 40.59%, and by dynamic state parameter, ΔC30 /ΔG30 , which increased by 24.66% and 167.67%, for the BID and QD groups, respectively. Dorzagliatin was well tolerated in both regimens, with good pharmacokinetic profiles. CONCLUSIONS: Dorzagliatin treatment for 28 days in Chinese T2D patients, selected according to predefined biomarkers, resulted in significant improvement in ß-cell function and glycaemic control. The safety and pharmacokinetic profile of dorzagliatin supports a subsequent Phase II trial design and continued clinical development.

Dorzagliatin monotherapy in Chinese patients with type 2 diabetes: a dose-ranging, randomised, double-blind, placebo-controlled, phase 2 study.

BACKGROUND: Glucokinase acts as a glucose sensor in the pancreas and a glucose processor in the liver, and has a central role in glucose homoeostasis. Dorzagliatin is a new, dual-acting, allosteric glucokinase activator that targets both pancreatic and hepatic glucokinases. Dorzagliatin has good pharmacokinetic and pharmacodynamic properties in humans, and provides effective 24-h glycaemic control and improves glucose sensitivity in patients with type 2 diabetes. We aimed to assess the efficacy and safety of dorzagliatin monotherapy at different doses in Chinese patients with type 2 diabetes. METHODS: In this multicentre, randomised, double-blind, placebo-controlled, phase 2 study, we randomly assigned (1:1:1:1:1) patients to receive oral placebo or one of four doses of oral dorzagliatin (75 mg once a day, 100 mg once a day, 50 mg twice a day, or 75 mg twice a day) using permuted-block randomisation, with a block size of ten and without stratification. Eligible patients were men or non-fertile women (aged 40-75 years) with type 2 diabetes who had a BMI of 19·0-30·0 kg/m2, were on a diet and exercise regimen, and were previously untreated or treated with metformin or α-glucosidase inhibitor monotherapy. The study started with a 4-week placebo run-in period followed by a 12-week treatment period. The primary endpoint was the change in HbA1c from baseline to week 12, which was assessed in all patients who received at least one dose of study drug and had both baseline and at least one post-baseline HbA1c value. Safety was assessed in all patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov, number NCT02561338. FINDINGS: Between Sept 29, 2015, and Aug 17, 2016, we randomly assigned 258 patients to one of the five study groups. At the end of 12 weeks, the least squares mean change in HbA1c from baseline was -0·35% (95% CI -0·60 to -0·10) in the placebo group, -0·39% (-0·64 to -0·14) in the 75 mg once daily group, -0·65% (-0·92 to -0·38) in the 100 mg once daily group, -0·79% (-1·06 to -0·52) in the 50 mg twice daily group, and -1·12% (-1·39 to -0·86) in the 75 mg twice daily group. Compared with the placebo group, the change in HbA1c between baseline and 12 weeks was significant in the 50 mg twice daily (p=0·0104) and the 75 mg twice daily (p<0·0001) groups. The number of adverse events was similar between the treatment groups and the placebo group. There were no reports of drug-related serious adverse events or severe hypoglycaemia. INTERPRETATION: Dorzagliatin had a beneficial effect on glycaemic control and was safe and well tolerated over 12 weeks in Chinese patients with type 2 diabetes. FUNDING: Hua Medicine, National Major Scientific and Technological Special Project for Significant New Drugs Development, Shanghai Science and Technology Innovation Action Project, Shanghai Pudong District Science and Technology Innovation Action Project, and Shanghai Municipal Commission of Economy and Informatisation Innovation Action Project.

Safety, tolerability, pharmacokinetics, and pharmacodynamics of novel glucokinase activator HMS5552: results from a first-in-human single ascending dose study.

BACKGROUND: HMS5552, a novel fourth-generation glucokinase (GK) activator, has demonstrated promising effects on glycemic control in preclinical models of type 2 diabetes. This single ascending dose study was conducted to investigate the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of HMS5552 during its first-in-human exposure. METHODS: Sixty healthy subjects were enrolled. In each of six dose-cohorts (5, 10, 15, 25, 35, and 50 mg), ten subjects were randomized with eight subjects receiving the same cohort-dose of HMS5552 and two receiving placebo. Plasma HMS5552 exposure, glucose, and insulin were measured repeatedly during fasting and after a standardized meal. Assessment included safety, PK, and PD endpoints. RESULTS: HMS5552 showed dose-proportional increases in area under the curve 0 to the last quantifiable concentration (AUC0-t) and maximum plasma concentration (Cmax). Slopes estimated by linear regression for AUC0-t and Cmax were ~1.0 (0.932 and 0.933, respectively). Geometric mean elimination half-life ranged from 4.48 to 7.51 hours and apparent clearance ranged from 11.5 to 13.1 L/h across all doses. No significant sex effect was observed in PK parameters. HMS5552 also demonstrated dose-related PD responses in terms of maximum glucose change from baseline (%) and mean glucose area under effect curve 0-4 hours change from baseline (%) (P<0.001). Fifteen adverse events were reported by nine subjects (ten with HMS5552 and five with the placebo). All adverse events were mild in intensity and resolved without any treatment. CONCLUSION: This first-in-human single ascending dose study provided predicted PK of HMS5552 with dose-proportional increases in AUC0-t and Cmax, as well as dose-related glucose-lowering effects over the range of 5-50 mg in healthy subjects. HMS5552 at doses up to 50 mg in healthy subjects was safe and well-tolerated.

Antitumor agents 268. Design, synthesis, and mechanistic studies of new 9-substituted phenanthrene-based tylophorine analogues as potent cytotoxic agents.

Nineteen new phenanthrene-based tylophorine analogues with various functional groups on the piperidine moiety were designed, synthesized, and evaluated for in vitro anticancer activity against four human tumor cell lines. Analogues 15 and 21 showed approximately 2-fold enhanced inhibitory activity as compared with our prior lead compound (PBT-1). Analogues 23 and 24 with S- and R-configured substituents, respectively, at the piperidine 3'-position exhibited comparable cytotoxicity to that of PBT-1. Furthermore, mechanistic studies to investigate the effects of the new compounds on Akt protein in lung cancer cells and the NF-kB signaling pathway suggested that the compounds may exert their inhibitory activity on tumor cells through inhibition of activation of both Akt and NF-kB signaling pathway.

Jadomycin B, an Aurora-B kinase inhibitor discovered through virtual screening.

Aurora kinases have emerged as promising targets for cancer therapy because of their critical role in mitosis. These kinases are well-conserved in all eukaryotes, and IPL1 gene encodes the single Aurora kinase in budding yeast. In a virtual screening attempt, 22 compounds were identified from nearly 15,000 microbial natural products as potential small-molecular inhibitors of human Aurora-B kinase. One compound, Jadomycin B, inhibits the growth of ipl1-321 temperature-sensitive mutant more dramatically than wild-type yeast cells, raising the possibility that this compound is an Aurora kinase inhibitor. Further in vitro biochemical assay using purified recombinant human Aurora-B kinase shows that Jadomycin B inhibits Aurora-B activity in a dose-dependent manner. Our results also indicate that Jadomycin B competes with ATP for the kinase domain, which is consistent with our docking prediction. Like other Aurora kinase inhibitors, Jadomycin B blocks the phosphorylation of histone H3 on Ser10 in vivo. We also present evidence suggesting that Jadomycin B induces apoptosis in tumor cells without obvious effects on cell cycle. All the results indicate that Jadomycin B is a new Aurora-B kinase inhibitor worthy of further investigation.

Isolation and characterization of N98-1272 A, B and C, selective acetylcholinesterase inhibitors from metabolites of an actinomycete strain.

A high throughput screening was carried out in order to search for inhibitors of acetylcholinesterase (AChE) from microorganism metabolites. An actinomycete strain was found to produce active compounds named N98-1272 A, B and C with IC50 of 15.0, 11.5, 12.5 microM, respectively. Structural studies revealed that the three compounds are identical to the known antibiotics, Manumycin C, B and A. Kinetic analyses showed that N98-1272 C (Manumycin A) acted as a reversible noncompetitive inhibitor of acetylcholinesterase, with a Ki value of 7.2 microM. The cyclohexenone epoxide part of the structure plays a crucial role in the inhibitory activity against AChE. Compared with Tacrine, N98-1272 A, B, and C exhibit much better selectivity toward AChE over BuChE.

Identification of novel human high-density lipoprotein receptor Up-regulators using a cell-based high-throughput screening assay.

Scavenger receptor class B type I (SR-BI) is the high-affinity high-density lipoprotein (HDL) receptor, and CLA-1 is the human homologue of the murine SR-BI. CLA-1/SR-BI receptor has been suggested as a new preventative and/or therapeutic target for atherosclerosis due to its pivotal role in overall HDL cholesterol (HDL-C) metabolism and its antiatherogenic activity in vivo. To search for active compounds that can increase CLA-1 transcription, a novel cell-based assay was developed for application in high-throughput screening (HTS). Human hepatoma HepG2 cells were transfected with a CLA-1-promoter-luciferase reporter gene construct, and the stable transfected cell line was selected and named CLAp-LUC HepG2. With rosiglitazone as a positive control, this stable cell line was used to establish a specific CLA-1 gene expression assay in a 96-well microplate format. The evaluating parameter Z' value of 0.64 showed that this cell-based HTS assay was robust and reliable. Screening of 6000 microbial secondary metabolite crude extracts identified 8 positive strains. Between 2 identified CLA-1 up-regulators produced by actinomycete strain 04-4776, 4776B may stimulate not only the expression of CLA-1 on the transcriptional and translational levels but also the activity of CLA-1 to uptake the HDL-C in HepG2 cells. The active compounds originated from this HTS assay may be developed to drug candidates or lead compounds for new antiatherosclerosis agents.