Relationship between inflammatory cells level and longer duration of hypertension in Chinese community residents.

BACKGROUND: To explore the relationship between duration of hypertension and inflammatory cell levels and to assess whether long duration might aggravate these inflammatory cells among Chinese urban community residents. METHODS: A cross-sectional study of 5199 hypertensive and 2675 no-hypertensive participants who registered in community health service centers for physical examination was performed in Tianjin, China. Data of blood pressure and inflammatory cells were collected. Binary logistic regression was performed to assess the effect of hypertensive duration on the level of inflammatory cells before and after adjustment for the potential confounding factors. RESULTS: Individuals with hypertension had significantly higher level of leukocyte count, neutrophil proportion, neutrophil-to-lymphocyte ratio (NLR), and lower level of lymphocyte proportion than those without hypertension. Two-way ANOVA showed that hypertension duration, rather than blood pressure control or their interaction, had significant influence on the levels of neutrophil proportion, lymphocyte proportion, and NLR. With the prolongation of the duration of hypertension, the level of neutrophil proportion and NLR increased, and the level of lymphocyte proportion decreased. Long hypertension duration (>10 years) was significantly associated with high level of neutrophil proportion (OR = 1.48, 95% CI: 1.25, 1.75), high level of NLR (OR = 1.53, 95% CI: 1.29, 1.81), and low level of lymphocyte proportion (OR = 1.54, 95% CI: 1.30, 1.82) in comparison with short duration (<5 years) after adjustment for confounding factors. CONCLUSION: Hypertensive patients had higher level of leukocyte count, neutrophil proportion, NLR, and lower level of lymphocyte proportion than normotensive ones. Long duration of hypertension was associated with aggravated inflammatory biomarkers.

The beneficial cutoffs of vitamin D for metabolic syndrome varies by sex among the elderly Chinese population: A cross-sectional study.

Metabolic syndrome (MetS) is a risk factor for various diseases with a high prevalence globally. We aimed to investigate the association of serum vitamin D levels with MetS, and we hypothesized that the beneficial cutoffs of vitamin D for MetS might vary by sex among urban people aged ≥60 years in Tianjin, China. This community-based cross-sectional study was conducted in 2 community health centers. We collected lifestyle and anthropometric information and measured serum 25(OH)D3 concentrations by high-performance liquid chromatography. MetS was diagnosed based on the 2009 International Diabetes Federation/American Heart Association/National Heart, Lung, and Blood Institute criterion. Binary logistic regression and stratification analysis were performed to determine the association between MetS and 25(OH)D3 levels. Among 840 eligible participants (347 males and 493 females), 439 (52.3%) were diagnosed with MetS. The prevalence rates of MetS in men and women were 52.7% and 51.9%, respectively (P = .82). In the whole population, no significant association was found between 25(OH)D3 and MetS, regardless of which 25(OH)D3 cutoff was used. After stratification by sex, men with serum 25(OH)D3 ≥40 ng/mL had a significantly lower risk of MetS before and after adjustment, with odds ratios (ORs) and 95% confidence intervals (CIs) of 0.55 (0.31-0.98) and 0.53 (0.29-0.96), respectively. For women, serum 25(OH)D3 ≥20 ng/mL was associated with a lower MetS risk, with unadjusted and adjusted ORs (95% CI) of 0.64 (0.43-0.95) and 0.61 (0.41-0.91), respectively. This association was more significant among females with respect to diastolic pressure and triglycerides. The beneficial cutoffs of serum 25(OH)D3 levels for MetS among men and women might be different.

Chemical synthesis of tetracyclic terpenes and evaluation of antagonistic activity on endothelin-A receptors and voltage-gated calcium channels.

A class of tetracyclic terpenes was synthesized and evaluated for antagonistic activity of endothelin-1 (ET-1) induced vasoconstriction and inhibitory activity of voltage-activated Ca(2+) channels. Three repeated Robinson annulation reactions were utilized to construct the tetracyclic molecules. A stereoselective reductive Robinson annulation was discovered for the formation of optically pure tricyclic terpenes. Stereoselective addition of cyanide to the hindered α-face of tetracyclic enone (-)-18 was found and subsequent transformation into the aldehyde function was affected by the formation of bicyclic hemiiminal (-)-4. Six selected synthetic tetracyclic terpenes show inhibitory activities in ET-1 induced vasoconstriction in the gerbil spiral modiolar artery with putative affinity constants ranging between 93 and 319 nM. Moreover, one compound, (-)-3, was evaluated further and found to inhibit voltage-activated Ca(2+) currents but not to affect Na(+) or K(+) currents in dorsal root ganglion cells under similar concentrations. These observations imply a dual mechanism of action. In conclusion, tetracyclic terpenes represent a new class of hit molecules for the discovery of new drugs for the treatment of pulmonary hypertension and vascular related diseases.

Structural insights into inhibition of the bivalent menin-MLL interaction by small molecules in leukemia.

Menin functions as a critical oncogenic cofactor of mixed lineage leukemia (MLL) fusion proteins in the development of acute leukemias, and inhibition of the menin interaction with MLL fusion proteins represents a very promising strategy to reverse their oncogenic activity. MLL interacts with menin in a bivalent mode involving 2 N-terminal fragments of MLL. In the present study, we reveal the first high-resolution crystal structure of human menin in complex with a small-molecule inhibitor of the menin-MLL interaction, MI-2. The structure shows that the compound binds to the MLL pocket in menin and mimics the key interactions of MLL with menin. Based on the menin-MI-2 structure, we developed MI-2-2, a compound that binds to menin with low nanomolar affinity (K(d) = 22nM) and very effectively disrupts the bivalent protein-protein interaction between menin and MLL. MI-2-2 demonstrated specific and very pronounced activity in MLL leukemia cells, including inhibition of cell proliferation, down-regulation of Hoxa9 expression, and differentiation. Our results provide the rational and essential structural basis to design next generation of inhibitors for effective targeting of the menin-MLL interaction in leukemia and demonstrate a proof of concept that inhibition of complex multivalent protein-protein interactions can be achieved by a small-molecule inhibitor.

Menin-MLL inhibitors reverse oncogenic activity of MLL fusion proteins in leukemia.

Translocations involving the mixed lineage leukemia (MLL) gene result in human acute leukemias with very poor prognosis. The leukemogenic activity of MLL fusion proteins is critically dependent on their direct interaction with menin, a product of the multiple endocrine neoplasia (MEN1) gene. Here we present what are to our knowledge the first small-molecule inhibitors of the menin-MLL fusion protein interaction that specifically bind menin with nanomolar affinities. These compounds effectively reverse MLL fusion protein-mediated leukemic transformation by downregulating the expression of target genes required for MLL fusion protein oncogenic activity. They also selectively block proliferation and induce both apoptosis and differentiation of leukemia cells harboring MLL translocations. Identification of these compounds provides a new tool for better understanding MLL-mediated leukemogenesis and represents a new approach for studying the role of menin as an oncogenic cofactor of MLL fusion proteins. Our findings also highlight a new therapeutic strategy for aggressive leukemias with MLL rearrangements.

Electrochemical determination of dopamine in the presence of ascorbic acid and uric acid using the synergistic effect of gold nanoflowers and L-cysteamine monolayer at the surface of a gold electrode.

This paper describes a facile and effective method to synthesize gold nanoflowers (AuNFs) by a controllable electrodeposition method induced by a L-cysteamine (L-Cys) monolayer self-assembled on the surface of a gold electrode. The AuNFs/L-Cys/Au electrodes were characterized by field emission scanning electron microscopy (FE-SEM), cyclic voltammetry, and AC impedance spectroscopy methods. This obtained AuNFs/L-Cys/Au electrode exhibits excellent electrocatalytic activity towards the oxidation of dopamine (DA) due to the synergistic effect of AuNFs and a L-Cys monolayer. Differential pulse voltammetry (DPV) experiment results show that the oxidation peak of DA is separated from the oxidation peaks of ascorbic acid (AA) and uric acid (UA), which can be used to detect DA in the presence of AA and UA, and the results are satisfactory.

Bioactivity and molecular targets of novel substituted quinolines in murine and human tumor cell lines in vitro.

Substituted quinolines (PQ code number), which reduce colony formation and increase gap junctional intercellular communication, were tested for their ability to interact with various molecular targets in murine and human tumor cell lines in vitro. Various markers of tumor cell metabolism, DNA fragmentation, mitotic disruption, apoptosis induction and growth factor receptor signaling pathways were assayed in vitro to evaluate drug cytotoxicity. Based on its ability to inhibit the metabolic activity of suspension cultures of leukemic L1210 cells at days 2 and 4 in vitro, PQ1 succinic acid salt is the most effective antiproliferative agent among the synthetic quinoline analogs tested. Moreover, antiproliferative PQ1 is effective across a spectrum of monolayer cultures of pancreatic Pan02, epidermoid A-431 and mammary SK-BR-3 and BT-474 tumor cells. PQ1 also blocks Ki-67 expression, a marker of tumor cell proliferation. A 1.5- to 3-h treatment with PQ1 is sufficient to inhibit the incorporations of [3H]-thymidine into DNA, [3H]-uridine into RNA and [3H]-leucine into protein used to assess the rates of macromolecule syntheses over a 0.5- or 1-h period of pulse-labeling in L1210 tumor cells. A 15-min pretreatment with PQ1 inhibits the cellular transport of both purine and pyrimidine nucleosides over a 30-sec period in vitro, suggesting that PQ1 may prevent the incorporation of [3H]-adenosine and [3H]-thymidine into DNA because it rapidly blocks the uptake of these nucleosides by the tumor cells. Since PQ1 does not reduce the fluorescence of the ethidium bromide-DNA complex, it does not directly bind to or destabilize double-stranded DNA. Over a 6- to -48-h period, PQ1 has very little effect on the mitotic index of L1210 cells but stimulates the formation of many binucleated cells and a few micronuclei, suggesting that this compound might increase mitotic abnormality, induce chromosomal damage or missegregation, and block cytokinesis. The fact that PQ1 induces initiator caspase-2 and effector caspase-3 activities and poly(ADP-ribose) polymerase-1 cleavage within 1-4 h and internucleosomal DNA fragmentation within 24 h in L1210 cells suggests that this antitumor drug can trigger the early and late events required for cells to undergo apotosis. Whole-cell immunodetection and Western blot analysis indicate that, in contrast to 17-(allylamino)-17-demethoxygeldanamycin and radicicol, PQ1 fails to down-regulate the protein level at 24 h and autophosphorylation at 3 h of membrane-anchored HER1 in A-431 cells and HER2 in SK-BR-3 cells, suggesting that this antitumor compound is unlikely to interact with and inhibit Hsp90 and the epidermal growth factor (EGF) receptor signaling pathways. In conclusion, antiproliferative PQ1 is effective against a spectrum of tumor cells and might interact with various membrane and nuclear targets to enhance gap junctions, inhibit nucleoside transport and block cytokinesis but does not appear to disrupt the EGF receptor-mediated signaling pathways to induce growth arrest and apoptosis.

Candidate anti-A beta fluorene compounds selected from analogs of amyloid imaging agents.

Alzheimer's disease (AD) is characterized by depositions of beta-amyloid (A beta) aggregates as amyloid in the brain. To facilitate diagnosis of AD by radioligand imaging, several highly specific small-molecule amyloid ligands have been developed. Because amyloid ligands display excellent pharmacokinetics properties and brain bioavailability, and because we have previously shown that some amyloid ligands bind the highly neurotoxic A beta oligomers (A beta O) with high affinities, they may also be valuable candidates for anti-A beta therapies. Here we identified two fluorene compounds from libraries of amyloid ligands, initially based on their ability to block cell death secondary to intracellular A beta O. We found that the lead fluorenes were able to reduce the amyloid burden including the levels of A beta O in cultured neurons and in 5xFAD mice. To explain these in vitro and in vivo effects, we found that the lead fluorenes bind and destabilize A beta O as shown by electron paramagnetic resonance spectroscopy studies, and block the harmful A beta O-synapse interaction. These fluorenes and future derivatives, therefore, have a potential use in AD therapy and research.

Synthesis, molecular targets, and antitumor activities of substituted tetrahydro-1-oxopyrano[4,3-b][1]benzopyrans and nanogels for drug delivery.

A class of substituted 1H,7H-5a,6,8,9-tetrahydro-1-oxopyrano[4,3-b][1]benzopyrans (tricyclic pyrones; TPs) was synthesized from a one-pot condensation reaction of 6-substituted 4-hydroxy-2-pyrones and cyclohexenecarboxaldehydes. The reaction involves a 6pi-electrocyclic ring closing process, and stereo- and regioselectivities were examined. C3-Pyridyl-containing TPs may represent a novel synthetic class of microtubule de-stabilizing anti-cancer drugs that inhibit macromolecule synthesis, tubulin polymerization, and the proliferation of a spectrum of wild-type and multi-drug resistant tumor cell lines in vitro. A linear skeleton with a N-containing aromatic ring attached at C3 of the top A-ring, a central pyran B-ring and a six-membered bottom C-ring with no alkylation at C7 are required for the antitumor activities of the lead compounds, a 3-pyridyl benzopyran (code name H10) and its 2-pyridyl regioisomer (code name H19). In addition to interacting with the colchicine-binding site to inhibit tubulin polymerization and increase the mitotic index, these TP analogs also block the cellular transport of nucleosides to inhibit DNA synthesis more effectively than other antimitotic agents. The anticancer potential of TPs in vivo is suggested by the fact that i.p. injections of H10 decrease the growth of solid tumors in mice inoculated with lung or ovarian carcinomas. A drug-delivery system involving nanogels was studied. We incorporated the anticancer compound, 6-hydroxymethyl-1,4-anthracenedione (code name AQ10) into PEG-PEI nanogel, and found that AQ10-encapsulated nanogel PEG-PEI is significantly more effective in altering the growth of Pan 02 (pancreatic cancer) cells compared to AQ10 or nanogel PEG-PEI alone. Since AQ10 is insoluble in water, PEG-PEI encapsulation represents a way to solubilize and deliver this as well as other poorly soluble compounds.

Inhibition of Alzheimer's amyloid toxicity with a tricyclic pyrone molecule in vitro and in vivo.

Small beta-amyloid (Abeta) 1-42 aggregates are toxic to neurons and may be the primary toxic species in Alzheimer's disease (AD). Methods to reduce the level of Abeta, prevent Abeta aggregation, and eliminate existing Abeta aggregates have been proposed for treatment of AD. A tricyclic pyrone named CP2 is found to prevent cell death associated with Abeta oligomers. We studied the possible mechanisms of neuroprotection by CP2. Surface plasmon resonance spectroscopy shows a direct binding of CP2 with Abeta42 oligomer. Circular dichroism spectroscopy reveals monomeric Abeta42 peptide remains as a random coil/alpha-helix structure in the presence of CP2 over 48 h. Atomic force microscopy studies show CP2 exhibits similar ability to inhibit Abeta42 aggregation as that of Congo red and curcumin. Atomic force microscopy closed-fluid cell study demonstrates that CP2 disaggregates Abeta42 oligomers and protofibrils. CP2 also blocks Abeta fibrillations using a protein quantification method. Treatment of 5x familial Alzheimer's disease mice, a robust Abeta42-producing animal model of AD, with a 2-week course of CP2 resulted in 40% and 50% decreases in non-fibrillar and fibrillar Abeta species, respectively. Our results suggest that CP2 might be beneficial to AD patients by preventing Abeta aggregation and disaggregating existing Abeta oligomers and protofibrils.

Protection of retinal cells from ischemia by a novel gap junction inhibitor.

Retinal cells which become ischemic will pass apoptotic signal to adjacent cells, resulting in the spread of damage. This occurs through open gap junctions. A class of novel drugs, based on primaquine (PQ), was tested for binding to connexin 43 using simulated docking studies. A novel drug has been synthesized and tested for inhibition of gap junction activity using R28 neuro-retinal cells in culture. Four drugs were initially compared to mefloquine, a known gap junction inhibitor. The drug with optimal inhibitory activity, PQ1, was tested for inhibition and was found to inhibit dye transfer by 70% at 10 microM. Retinal ischemia was produced in R28 cells using cobalt chloride as a chemical agent. This resulted in activation of caspase-3 which was prevented by PQ1, the gap junction inhibitor. Results demonstrate that novel gap junction inhibitors may provide a means to prevent retinal damage during ischemia.

Combination of nanogel polyethylene glycol-polyethylenimine and 6(hydroxymethyl)-1,4-anthracenedione as an anticancer nanomedicine.

Polyethylene glycol-polyethylenimine (PEG-PEI) nanogels have been used to deliver nucleic acids and oligonucleotides into cells. First, we synthesized PEG-PEI nanogels with methylene proton ratios (CH2O:CH2N) in PEG-PEI ranging from approximately 6.8:1 to 4:1 and less, as shown by 1H NMR spectra. We first synthesized various nanogels with varying ratios of CH2O:CH2N (methylene proton) in PEG-PEI as shown by 1H NMR spectra and tested their cytotoxicity using a rodent pancreatic adenocarcinoma cell line (Pan 02). We showed that the nanogel PEG-PEI with methylene proton ratio of 4:1 was strongly cytotoxic to Pan 02 cells in vitro, while the nanogel with the methylene proton ratio of 6.8:1 was not toxic. We incorporated a novel anti-cancer drug, 6-(hydroxymethyl)-1,4-anthracenedione (AQ) analogue (AQ10) into nontoxic nanogel PEG-PEI and tested the effect of AQ10 loaded nanogel PEG-PEI (AQ10-nanogel PEG-PEI) and AQ10 dissolved in DMSO on Pan 02 cell growth. The size of this AQ10-nanogel PEG-PEI was characterized using atomic force microscopy (AFM). Our studies showed that the AQ10-nanogel PEG-PEI is readily taken up by Pan 02 cells. Growth attenuation of Pan 02 cells treated with AQ10-nanogel PEG-PEI was three to four times that of cells treated with AQ10 dissolved in DMSO. These results suggest that PEG-PEI, usually used to deliver nucleic acids into cells, can also be used to deliver an insoluble small molecule anticancer drug, AQ10.

Synthesis and anti-breast cancer activities of substituted quinolines.

Promising anti-breast cancer agents derived from substituted quinolines were discovered. The quinolines were readily synthesized in a large scale from a sequence of reactions starting from 4-acetamidoanisole. The Michael addition product was isolated as the reaction intermediate in the ring closing reaction of 4-amino-5-nitro-2-(3-trifluoromethylphenyloxy)anisole with methyl vinyl ketone leading to 6-methoxy-4-methyl-8-nitro-5-(3-trifluoromethylphenyloxy)quinoline (14). The amino function of 8-amino-6-methoxy-4-methyl-5-(3-trifluoromethylphenyloxy)quinoline, prepared from 14, was connected to various side chains via alkylation with N-(3-iodopropyl)phthalimide, Michael addition with acrylonitrile, and reductive amination with various heterocycle carboxaldehydes, such as imidazole-4-carboxaldehyde, thiophene-2-carboxaldehyde, and 2-furaldehyde. Effects of the substituted quinolines on cell viability of T47D breast cancer cells using trypan blue exclusion assay were examined. The results showed that the IC(50) value of 6-methoxy-8-[(2-furanylmethyl)amino]-4-methyl-5-(3-trifluoromethylphenyloxy)quinoline is 16+/-3nM, the lowest IC(50) out of all the quinolines tested. IC(50) values of three other quinolines are in the nanomolar range, a desirable range for pharmacological testing.