1.First π-linker featuring mercapto and isocyano anchoring groups within the same molecule: Synthesis, heterobimetallic complexation and self-assembly on Au(111).
Applegate JC1, Okeowo MK1, Erickson NR1, Neal BM1, Berrie CL1, Gerasimchukand NN2, Barybin MV1. Chem Sci. 2016 Feb 1;7(2):1422-1429. Epub 2015 Nov 20.
Mercapto (-SH) and isocyano (-N≡C) terminated conducting π-linkers are often employed in the ever-growing quest for organoelectronic materials. While such systems typically involve symmetric dimercapto or diisocyano anchoring of the organic bridge, this article introduces the chemistry of a linear azulenic π-linker equipped with one mercapto and one isocyano terminus. The 2-isocyano-6-mercaptoazulene platform was efficiently accessed from 2-amino-6-bromo-1,3-diethoxycarbonylazulene in four steps. The 2-N≡C end of this 2,6-azulenic motif was anchrored to the [Cr(CO)5] fragment prior to formation of its 6-SH terminus. Metalation of the 6-SH end of [(OC)5Cr(η1-2-isocyano-1,3-diethoxycarbonyl-6-mercaptoazulene)] (7) with Ph3PAuCl, under basic conditions, afforded X-ray structurally characterized heterobimetallic Cr0/AuI ensemble [(OC)5Cr(μ-η1:η1-2-isocyano-1,3-diethoxycarbonyl-6-azulenylthiolate)AuPPh3] (8). Analysis of the 13C NMR chemical shifts for the [(NC)Cr(CO)5] core in a series of the related complexes [(OC)5Cr(2-isocyano-6-X-1,3-diethoxy-carbonylazulene)] (X = -N≡C, Br,H, SH, SCH2CH2CO2CH2CH3, SAuPPh3) unveiled remarkably consistent inverse-linear correlations δ( 13COtrans) vs.
2.Estrogen receptor subtypes mediate distinct microvascular dilation and reduction in [Ca2+]I in mesenteric microvessels of female rat.
Mazzuca MQ1, Mata KM1, Li W1, Rangan SS1, Khalil RA2. J Pharmacol Exp Ther. 2015 Feb;352(2):291-304. doi: 10.1124/jpet.114.219865. Epub 2014 Dec 3.
Estrogen interacts with estrogen receptors (ERs) to induce vasodilation, but the ER subtype and post-ER relaxation pathways are unclear. We tested if ER subtypes mediate distinct vasodilator and intracellular free Ca(2+) concentration ([Ca(2+)]i) responses via specific relaxation pathways in the endothelium and vascular smooth muscle (VSM). Pressurized mesenteric microvessels from female Sprague-Dawley rats were loaded with fura-2, and the changes in diameter and [Ca(2+)]i in response to 17β-estradiol (E2) (all ERs), PPT (4,4',4''-[4-propyl-(1H)-pyrazole-1,3,5-triyl]-tris-phenol) (ERα), diarylpropionitrile (DPN) (ERβ), and G1 [(±)-1-[(3aR*,4S*,9bS*)-4-(6-bromo-1,3-benzodioxol-5-yl)-3a,4,5,9b-tetrahydro:3H-cyclopenta(c)quinolin-8-yl]-ethanon] (GPR30) were measured. In microvessels preconstricted with phenylephrine, ER agonists caused relaxation and decrease in [Ca(2+)]i that were with E2 = PPT > DPN > G1, suggesting that E2-induced vasodilation involves ERα > ERβ > GPR30.
3.Estrogen regulates excitatory amino acid carrier 1 (EAAC1) expression through sphingosine kinase 1 (SphK1) transacting FGFR-mediated ERK signaling in rat C6 astroglial cells.
Huang C1, Yuan P2, Wu J1, Huang J3. Neuroscience. 2016 Apr 5;319:9-22. doi: 10.1016/j.neuroscience.2016.01.027. Epub 2016 Jan 22.
Excitatory amino acid carrier 1 (EAAC1) is one important subtype of the excitatory amino acid transporters (EAATs), and its absence can increase the vulnerability to oxidative stress in neural tissue. Enhanced expression of EAAC1 can provide neuroprotection in multiple disorders, including ischemia and multiple sclerosis. However, the mechanism regulating EAAC1 expression is not fully understood. Using rat C6 astroglial cells, which specifically express EAAC1, we found that 17β-estradiol (E2) and (±)-1-[(3aR(∗),4S(∗),9bS(∗))-4-(6-bromo-1,3-benzodioxol-5-yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinolin-8-yl]-ethanone (G1), an agonist of the G-protein-coupled estrogen receptor (GPR30), strongly increased EAAC1 protein levels and protected cells from hydrogen peroxide (H2O2) toxicity. We further found that E2/G1 activated sphingosine kinase 1 (SphK1) via GPR30, resulting in the transcription of fibroblast growth factor 2 (FGF2), which stimulated its receptor (FGFR) and led to the phosphorylation of FGFR substrate 2α (FRS2α).
4.The Selective Estrogen Receptor Modulator Raloxifene Regulates Arginine-Vasopressin Gene Expression in Human Female Neuroblastoma Cells Through G Protein-Coupled Estrogen Receptor and ERK Signaling.
Grassi D1, Ghorbanpoor S1, Acaz-Fonseca E1, Ruiz-Palmero I1, Garcia-Segura LM1. Endocrinology. 2015 Oct;156(10):3706-16. doi: 10.1210/en.2014-2010. Epub 2015 Jul 22.
The selective estrogen receptor modulator raloxifene reduces blood pressure in hypertensive postmenopausal women. In the present study we have explored whether raloxifene regulates gene expression of arginine vasopressin (AVP), which is involved in the pathogenesis of hypertension. The effect of raloxifene was assessed in human female SH-SY5Y neuroblastoma cells, which have been recently identified as a suitable cellular model to study the estrogenic regulation of AVP. Raloxifene, within a concentration ranging from 10(-10) M to 10(-6) M, decreased the mRNA levels of AVP in SH-SY5Y cells with maximal effect at 10(-7) M. This effect of raloxifene was imitated by an agonist (±)-1-[(3aR*,4S*,9bS*)-4-(6-bromo-1,3-benzodioxol-5-yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinolin-8-yl]-ethanone of G protein-coupled estrogen receptor-1 (GPER) and blocked by an antagonist (3aS*,4R*,9bR*)-4-(6-bromo-1,3-benzodioxol-5-yl)-3a,4,5,9b-3H-cyclopenta[c]quinoline of GPER and by GPER silencing.