Disease relevance of cis isomer

• We have identified the cis isomer of N6-(4-hydroxy-isopentenyl)-2-methylthioadenosine (ms2io6A) as a component of the tRNA of Salmonella typhimurium [1].
• Characterization of torsion angles and transient hydrogen bonds indicates that prolyl isomerization of the pThr-Pro peptide bond results from both destabilization of the N-terminal helix capping box and stabilization of the cis isomer by transient hydrogen bonds [2].
• Such a difference may be related to the failure of the cis isomer to induce pancreatic cancer in rats [3].
• Because DACH can exist as the trans-1R,2R, trans-1S,2S or cis isomer, the antitumor activity and toxicity of individual isomers of both DACH(sulfato)Pt(II) and DACH(1,1-cyclobutanedicarboxylato)Pt(II) complexes have been examined [4].
• Pharmacodynamics of the 1R cis-1'R cis isomer of atracurium (51W89) in health and chronic renal failure [5].

High impact information on cis isomer

• Knowledge of the number of base pairs between the bends in the cis isomer, which has the lowest electrophoretic mobility, allows calculation of the average helical repeat of the inserted sequence [6].
• To evaluate the effect of membrane lipid acyl-chain packing on the efficiency of cell lysis by complement, we have studied membrane modulation by 2-(2-methoxy)-ethoxyethyl-8-(cis-2-n-octylcyclopropyl)-octanoate (A2C) and by myristoleyl alcohol, the cis isomer of a C14:1 aliphatic alcohol [7].
• The basis for idoxifene's antitumor activity was examined by comparing the effectiveness of the clinically used transisomer (referred to here as idoxifene) with its cis-isomer, which has a 50-fold lower relative binding affinity for ER than idoxifene but similar calmodulin-inhibitory activity [8].
• In vitro, both CYP735As preferentially utilized isopentenyladenine nucleotides rather than the nucleoside and free base forms and produced tZ nucleotides but not the cis-isomer [9].
• The significant population of the cis isomer (9 %) present after phosphorylation of T20 suggests a potential role of selective recognition of cis versus trans isomers in response to phosphorylation of APP [2].

Chemical compound and disease context of cis isomer

• We have studied the pharmacodynamics of the 1R cis-1'R cis isomer of atracurium (51W89) in 15 healthy subjects and in 17 patients with chronic renal failure using a bolus dose of 51W89 0.1 mg kg-1 (2 x ED95) [5].
• The trans 5-nitroquinoline complex produced better sensitization in hypoxia than its cis isomer [enhancement ratio (ER) 1.7 at 10 microM versus 40 microM for cis] [10].
• For L = misonidazole, toxicity is similar to the monoammine, but higher in hypoxic than in aerobic cells. trans-[PtCl2(NH3)-(misonidazole)] is more toxic than the cis isomer [11].
• Immediately or 2 hours after intravenous injection of 8 mg/kg body weight of ATX-S10(Na), a cis isomer of ATX-S10, eyes were irradiated by a diode laser at the radiance of 3.25-65.3 J/cm(2) Vascular occlusion was identified by fundus photography, fluorescein angiography, and histology at 1, 3, 7, 14, and 28 days after PDT [12].
• This paper reviews intranasal formulations of a variety of available medications (dihydroergotamine mesylate [dihydroergotamine mesilate], sumatriptan, zolmitriptan, butorphanol, capsaicin and lidocaine [lignocaine]) and one experimental medication (civamide, a cis-isomer of capsaicin) for the treatment of migraine and cluster headache [13].

Biological context of cis isomer

• Fixed ring-trans-4-hydroxytamoxifen is a potent antiestrogen, and its cis isomer is a weak antiestrogen (IC50 congruent to 4 x 10(-8) to 2 x 10(-7) M) [14].
• The cis isomer also lacked appreciable affinity for [3H]-1a binding sites [15].
• The present results indicate that beta-C conformation plays a major role in its intestinal absorption and that cis isomer discrimination is at the levels of cellular uptake and incorporation into chylomicrons [16].
• Although cyclization of the radical derived from either substrate proceeds with modest selectivity for the cis-isomer, as does cycloisomerization of the aryllithium derived from substrate 1 (cis/trans approximately 2), intramolecular cyclization of the alkyllithium derived from substrate 2 is a highly cis-selective process (cis/trans = 12) [17].
• On the basis of earlier reports of reduced growth rate and fat accumulation in animals fed trans 18:1, a study was conducted to determine whether the effects of trans 18:1 on lipolysis and glucose utilization by adipocytes differed from effects of the cis isomer [18].

Anatomical context of cis isomer

• The corresponding concentrations of the cis isomer in adenoid tissue ranged from 0.40 to 4.20 micrograms/g and from 1.74 to 4.94 micrograms/g, respectively [19].
• The cis isomer was more potent in inducing tumors of the liver and pancreas than the trans isomer [20].
• 13-cis-Retinoic acid is the predominant cis isomer after incubation of intestinal mucosa homogenates with all-trans-retinoic acid [21].
• 4. The cis isomer stereoselectively blocked veratridine-induced (but not K(+)-induced) [(3)H]-GABA release from mouse synaptosomes (IC(50), 4.6 microM) [22].
• The cis isomer was retained longer in liver, particularly in mitochondria, but had low retention in that portion of the endoplasmic reticulum isolated as the rough membrane fraction [23].

Associations of cis isomer with other chemical compounds

• Preliminary testing of the isomers in the mouse rotarod assay indicates that the trans isomer (1b) is only slightly more active then the cis isomer (1a) [24].
• Exposure of rats to the sunlight for 2 days resulted in increase of the epidermal content of trans-urocanic acid from the normal value of 0.38 to 1.70 micrograms/mg wet wt. of skin, accompanied by formation de novo of the epidermal cis isomer [25].
• Upon irradiation with 366 nm light, the trans-cinnamate attached to the active-site serine isomerizes to the cis isomer which then rapidly lactonizes to release the free enzyme [26].
• However, proton magnetic resonance studies at high dilution in deuteriated solvents show that N-methylformamide exists as the cis isomer to the extent of 8% in water, 10.3% in chloroform, 8.8% in benzene, and 9.2% in cyclohexane [27].
• The cis isomer 2b had about one-third of the affinity of phencyclidine for the PCP receptor [28].

Gene context of cis isomer

• Moreover, (1S,3S)-ACPD, the cis isomer, shows negligible activity at group I receptors and is a good agonist of mGluR2 [29].
• A study of the relationship between biological activity and prolyl amide isomer geometry in oxytocin using 5-tert-butylproline to augment the Cys(6)-Pro(7) amide cis-isomer population [30].
• This is, to the best of our knowledge, the first example where cis isomer selectivity can be demonstrated for a proteinase [31].
• The rise in NO released was mimicked by either (R)-(+)-methanandamide or the vanilloid receptor agonists resiniferatoxin and (E)-capsaicin but not by its inactive cis-isomer (Z)-capsaicin [32].
• The absolute configuration at C-4 was determined to be S by locating the 13C label in the lactone ring of the trans isomeric lactone and in the hydroxymethyl group of the cis isomer following HPLC separation of both isomers and analysis by GC/MS/MS techniques [33].

Analytical, diagnostic and therapeutic context of cis isomer

• When measured by a high-pressure liquid chromatography method, peak concentrations of 12.09 and 18.04 micrograms of the cis isomer per ml were obtained at 1 h, with mean half-lives of 1.63 and 2.06 h and mean areas under the curve of 30.48 and 49.34 micrograms.h/ml in patients who received the 15- and 30-mg/kg doses, respectively [34].
• Ultraviolet (UV) irradition converts it to the cis-isomer that is an important mediator in UV-induced immunosuppression [35].
• The maximum plasma concentration of the cis isomer ranged from 12.3 micrograms/mL in subjects with normal renal function to 36.7 micrograms/mL in hemodialysis patients [36].
• Suberythemal sun exposures caused near-maximal UCA isomerization, and during heliotherapy the cis isomer constituted 63.7-74.3% of the total UCA concentration [37].
• The cis-isomer of ebelin lactone was also obtained as one of the artefacts of the aglycone and its structure revised [38].

References