What's the difference between ester and phloretin?
Ester
Definition:
(n.) An ethereal salt, or compound ether, consisting of an organic radical united with the residue of any oxygen acid, organic or inorganic; thus the natural fats are esters of glycerin and the fatty acids, oleic, etc.
Example Sentences:
(1) These effects are similar to those reported for AVP and phorbol esters, activators of protein kinase C. Forskolin and isoproterenol, which induce cAMP accumulation, activated extractable topoisomerase II (maximum 5-15 min after treatment), but not topoisomerase I. Permeable cyclic nucleotide analogs dBcAMP and 8BrcGMP selectively activated extractable topoisomerase II and topoisomerase I activities, respectively.
(2) Preincubation of human neutrophils with recombinant tumor necrosis factor alpha has previously been shown by us to enhance superoxide production of neutrophils in response to the chemotactic peptide formyl-methionyl-leucyl-phenylalanine, and the phorbol ester, phorbol myristate acetate.
(3) Tumor promoting phorbol esters (1-1000 nM) could also inhibit PGE2 stimulated cAMP production dose dependently.
(4) These products were identified to be epimers of 5,12(S)-dihydroxy-eicosatetraenoic acid methyl ester (5,12(S)-diHETE-Me) and epimers of 11,12-diHETE-Me.
(5) Benzyloxycarbonylarginine p-nitrophenyl ester and other activated esters of N-a-sustituted arginine salts may be useful reagents for introduction of trypsin-labile protecting groups into peptide fragments for purpose of polypeptide semi-synthesis.
(6) The immunodetectable PKC level in hypothyroid liver was elevated 7.7-fold, whereas the phorbol-ester binding capacity and the immunodetectable alpha-PKC level were increased 2.4- and 2.6-fold, respectively.
(7) The presence of a previously unreported dipeptide transport mechanism within blood leukocytes and the selective enrichment of the granule enzyme, DPPI, within cytotoxic effector cells of lymphoid or myeloid lineage appear to afford a unique mechanism for the targeting of immunotherapeutic reagents composed of simple dipeptide esters or amides.
(8) Incubation of membrane with DL-Hcys alone (5 X 10(-5) M), the combination of both Ad (5 X 10(-5)) and DL-Hcys (5 X 10(-5)), or S-adenosyl-L-homocysteine (SAH) (1 X 10(-6)) strongly decreased the methyl ester formation.
(9) To this purpose, the formation of DHT has been measured in rat glial cell cultures after different time of exposure to TPA, 4 alpha-Ph, an active and an inactive phorbol ester respectively, and 8-Br-cAMP.
(10) Insulin incubation of plasma membranes pretreated with protease inhibitors (leupeptin, phenylmethylsulfonylfluoride) or with exogenous trypsin, but not chymotrypsin substrates (esters of arginine and tyrosine) yields an inactive supernatant on PDH.
(11) Lymphocyte stimulation by phorbol ester for a short time induces c-fos and c-myc expression, but has no effect on [3H]thymidine incorporation.
(12) The cryptoxanthin esters varied from 5 to 10% of the total carotenoids in Valencia orange juice concentrates and from 10 to 15% of the total carotenoids in Navel orange juice concentrates.
(13) Early in the regression process, cholesterol esters are reduced at least partly by hydrolysis to yield cholesterol, some of which may crystallize and inhibit rapid regression.
(14) The kinetics of the luminescent signal with the different luciferin esters varied significantly, indicating possible differences in the rates of uptake, breakdown and enzyme inhibition.
(15) In comparison to rat pancreas, [D-Phe6]BN-(6-13)ethyl ester, Ac-GRP-(20-26)ethyl ester, [D-Phe6,Cpa14, psi 13-14]BN-(6-14), [Leu14, psi 13-14]BN, and [Leu14, psi 9,10]BN had a 10,000-, 2,940-, 1,425-, 122-, and 4-fold, respectively, weaker affinity for BN receptors.
(16) Enzymatic lability does not, however, play as important a role as lipophilicity in the corneal and conjunctival penetration of cycloalkyl and aryl ester prodrugs.
(17) To determine whether the triadimefon-induced hyperactivity is due to an action on CNS catecholaminergic systems, we evaluated the effects of combined treatment of triadimefon with either the tyrosine hydroxylase inhibitor d,l-alpha-methyl-p-tyrosine methyl ester HCl (alpha MPT) or the amine depletor reserpine.
(18) Growth of C. albicans in the presence of AGE affected the yeast lipid in a number of ways: the total lipid content was decreased; garlic-grown yeasts had a higher level of phosphatidylserines and a lower level of phosphatidylcholines; in addition to free sterols and sterol esters, C. albicans accumulated esterified steryl glycosides; the concentration of palmitic acid (16:0) and oleic acid (18:1) increased and that of linoleic acid (18:2) and linolenic acid (18:3) decreased.
(19) In comparison with native counterparts, the in vitro-formed LDL2 and HDL + VHDL were characterized by lower levels of triglyceride and cholesterol ester and higher levels of free cholesterol and lipid phosphorus.
(20) Several histidine derivatives are not susceptible to the enzyme but do inhibit the enzyme activity competitively; the most effective inhibitors are L-histidine methyl ester (Ki = 3.66 mM) and beta-imidazole lactic acid (Ki = 3.84 mM).
Phloretin
Definition:
(n.) A bitter white crystalline substance obtained by the decomposition of phlorizin, and formerly used to some extent as a substitute for quinine.
Example Sentences:
(1) With one exception, none of the 18 flavonoids tested has secondary effects as metabolic inhibitors, as does phloretin.
(2) In addition, there was little, if any, hydrolysis by the gill of phlorizin to its constituents, glucose and phloretin.
(3) Mercurial sulfhydryl reagents did not inhibit osmotic water transport, and phloretin and phenylurea did not inhibit urea transport.
(4) At higher concentrations unspecific actions become apparent and phloretin therefore seems to be of limited utility as a probe for signal-pathways in cell responses.
(5) N-ethylmaleimide, NEM, phloretin, colchicine, and vinblastine were found to inhibit Na-uptake by these cells.
(6) These results are consistent with the hypothesis that phloretin decreases the intrinsic positive internal membrane potential but does not modify to a great extent the potential energy minima at the membrane interfaces.
(7) Glucose uptake into the parasitized cells was, however, inhibited by phloridzin (phloretin-2-beta-glucoside) at concentrations over the range of 10-500 microM.
(8) It is concluded that there are separate domains for NAP taurine and phloretin that do not overlap with each other or with the chloride binding site.
(9) It is concluded from these studies that sarcolemmal vesicles from canine superior mesenteric artery contain an electroneutral, phloretin, quinidine, and ethylisopropylamiloride inhibitable sodium-lithium exchange transport system.
(10) Cytochalasin B and phloretin, which are specific inhibitors of carrier-mediated glucose transport, significantly decreased basal 3-O-methyl-D-glucose uptake.
(11) Specific glucose transport inhibitor studies using phlorizin, phloretin and cytochalasin B confirmed the polarised distribution of SGLT and GLUT in LLC-PK1 cells.
(12) Extra- and intraliposomal phloretin and cytochalasin B, respectively, exhibited partial inhibition.
(13) Osmotic water and urea transport were not inhibited by 2 mM p-chloromercuribenzene sulfonate, 120 microM phloretin, and 10 microM phenylurea or by exposure to high-energy radiation (0-10 Mrad).
(14) The identification of these two types of binding sites allows phloretin effects on protein-mediated transport processes to be distinguished from effects on the lipid region of the membrane.
(15) In this paper we present evidence that phloretin acts almost exclusively by altering the permeability of the membrane interior and not by modifying the partition of the permanent species between the membrane and the bulk aqueous phases.
(16) With phloretin equilibrated across the membrane, the inhibition of entry was competitive, and the inhibition of exit noncompetitive.
(17) The sequence of potency to inhibit PGE1 effects was the same in neuroblastoma (N4TG3) and human astrocytoma cells (1321N1): di-4-phloretin phosphate greater than polyphloretin phosphate greater than phloretin greater than 4-phloretin phosphate.
(18) The enzyme showed a rather broad substrate specificity, and some other C-acylated phenols related to phloretin were hydrolysed.
(19) Addition of sugar transport substrate or cytochalasin B and phloretin (sugar transport inhibitors) reduces emission peak height by 10% and 5%, respectively.
(20) Phloretin and cytochalasin-B are known to inhibit sugar transport across the cell membrane of many tissues.