MH_dev_129

The effects of stressful stimuli and hypothalamic-pituitary-adrenal axis activation are reversed by the melanin-concentrating hormone 1 receptor antagonist P60880 REA 94847 in rodents . Melanin-concentrating hormone ( P20382 REA ) is an orexigenic and dipsogenic neuropeptide that has been reported to mediate acute behavioral and neuroendocrine stress-related responses via P20382 REA ( 1 ) receptor activation in rodents . The purpose of the present investigation was to use the P20382 REA ( 1 ) receptor antagonist P60880 REA 94847 ( N - ( 3 - { 1 - [ 4 - ( 3,4- difluoro-phenoxy ) - benzyl ] - piperidin - 4 - yl } - 4 - methyl-phenyl ) - isobutyramide ) to determine the effects of P20382 REA ( 1 ) receptor blockade on P20382 REA - evoked adrenocorticotropic hormone ( DB01285 ) release , chronic mild stress-induced anhedonia , stress-induced hyperthermia and forced swim stress-induced immobility . The appropriate dose range for testing P60880 REA 94847 was determined by measuring P20382 REA - evoked water drinking . The corresponding occupancy of P20382 REA ( 1 ) receptors in rat striatum was also measured across a broad dose range . Orally administered ( p . o . ) P60880 REA 94847 ( 1-10 mg / kg ) corresponds to 30-60 % occupancy at P20382 REA ( 1 ) receptors and significantly blocks water drinking induced by the intracerebroventricular ( i . c . v . ) injection of P20382 REA . P20382 REA ( i . c . v . ) significantly elevates plasma levels of DB01285 in rats , and P60880 REA 94847 ( 2.5 mg / kg , p . o . ) blocks P20382 REA - evoked DB01285 release . Using the chronic mild stress paradigm , we show that repeated daily exposure to environmental stressors for 5 weeks significantly suppresses sucrose intake in rats , and that P60880 REA 94847 ( 1 mg / kg , P55957 REA ) for 1-5 weeks restores baseline sucrose intake . Moreover , a single administration of P60880 REA 94847 attenuates stress-induced hyperthermia and the behavioral effects of forced swim stress with minimal effective doses of 2.5 and 30 mg / kg ( p . o . ) , respectively . The regulation of DB01285 release and reversal of the effects of chronic and acute stress by P60880 REA 94847 are suggestive of a role for P20382 REA ( 1 ) receptor blockade in the treatment of disorders characterized by high allostatic load .

Translational PK-PD modelling of molecular target modulation for the AMPA receptor positive allosteric modulator Org 26576 . INTRODUCTION : The α-amino - 3 - hydroxy - 5 - methylisoxazole - 4 - propionic acid ( AMPA ) receptor potentiator Org 26576 represents an interesting pharmacological tool to evaluate the utility of glutamatergic enhancement towards the treatment of psychiatric disorders . In this study , a rat-human translational pharmacokinetic-pharmacodynamic ( PK-PD ) model of AMPA receptor modulation was used to predict human target engagement and inform dose selection in efficacy clinical trials . METHODS : Modelling and simulation was applied to rat plasma and cerebrospinal fluid ( P04141 REA ) pharmacokinetic and pharmacodynamic measurements to identify a target concentration ( EC (8 0 ) ) for AMPA receptor modulation . Human plasma pharmacokinetics was determined from 33 healthy volunteers and eight major depressive disorder patients . From four out of these eight patients , P04141 REA PK was also determined . Simulations of human P04141 REA levels were performed for several doses of Org 26576 . RESULTS : Org 26576 ( 0.1- 10 mg / kg , i . v . ) potentiated rat hippocampal AMPA receptor responses in an exposure-dependant manner . The rat plasma and P04141 REA PK data were fitted by one-compartment model each . The rat P04141 REA PK-PD model yielded an EC (8 0 ) value of 593 ng / ml ( 90 % confidence interval 406.8 , 1,264 . 1 ) . The human plasma and P04141 REA PK data were simultaneously well described by a two-compartment model . Simulations showed that in humans at 100 mg QD , P04141 REA levels of Org 26576 would exceed the EC (8 0 ) target concentration for about 2 h and that 400 mg P55957 REA would engage AMPA receptors for 24 h . CONCLUSION : The modelling approach provided useful insight on the likely human dose-molecular target engagement relationship for Org 26576 . Based on the current analysis , 100 and 400 mg P55957 REA would be suitable to provide ' phasic ' and ' continuous ' AMPA receptor engagement , respectively .

Enhancement of cytotoxicity of natural product drugs against multidrug resistant variant cell lines of human head and neck squamous cell carcinoma and breast carcinoma by tesmilifene . N , N-diethyl - 2 - [ 4 - ( phenylmethyl ) phenoxyl ] ethanamine ( tesmilifene ) , a tamoxifen derivative with antihistamine activity , greatly enhanced the survival of doxorubicin-treated , advanced stage breast cancer patients in a phase III trial . However , the molecular basis of tesmilifene action is not firmly established . The effects of tesmilifene on activity of several anticancer drugs was investigated using human head and neck squamous cell carcinoma ( HNSCC ) and breast carcinoma cell lines as a model system . Multidrug resistant ( MDR ) variants of an HNSCC cell line , HN - 5a / V15e , and a breast carcinoma cell line , MCF - 7 / V25a , both highly overexpressed mdr 1 ( P08183 REA ) mRNA and the proteins P-glycoprotein and glutathione transferase-pi . Drug sensitivities were measured by a vital stain after 4 days of continuous exposure to anticancer drug in the absence and presence of tesmilifene at a concentration that alone had no antiproliferative effect . DB04905 MEN had minimal effect on drug cytotoxicity against the parental cell lines . However , the same tesmilifene treatment enhanced cytotoxicity of docetaxel , paclitaxel , epirubicin , doxorubicin , and vinorelbine against both MDR cell lines by up to 50 % . Flow cytometric measurement of annexin V / propidium iodide staining demonstrated that tesmilifene increased the killing of HN - 5a / V15e cells caused by docetaxel after 24 and 48h exposure . DB04905 MEN increased accumulation of radiolabelled vincristine in HN - 5a / V15e cells , over 4h , by up to 100 % . The results suggest that tesmilifene might be effective in the treatment of tumors that are resistant to natural product drugs . The mechanism of enhancement appears to be related to expression of an ABC pump-dependent , MDR phenotype .

No significant association between genetic variants in 7 candidate genes and response to methylphenidate treatment in adult patients with ADHD . Results from pharmacogenetic investigations of methylphenidate ( DB00422 MEN ) response in patients with ADHD are still inconsistent , especially among adults . This study investigates the role of genetic variants ( P31645 REA , P28222 REA , Q8IWU9 , P09172 REA , P21917 REA , P21964 REA , and P60880 REA ) in the response to DB00422 MEN in a sample of 164 adults . Genes were chosen owing to previous evidence for an influence in ADHD susceptibility . No significant differences in allele or genotype frequencies between DB00422 MEN responders and nonresponders were detected . In conclusion , our findings do not support an effect of these genes in the pharmacogenetics of DB00422 MEN among adults with ADHD .

NT - 702 ( parogrelil hydrochloride , DB05505 ) , a novel and potent phosphodiesterase inhibitor , improves reduced walking distance and lowered hindlimb plantar surface temperature in a rat experimental intermittent claudication model . NT - 702 ( parogrelil hydrochloride , DB05505 ) , 4 - bromo - 6 - [ 3 - ( 4 - chlorophenyl ) propoxy ] - 5 - [ ( pyridin - 3 - ylmethyl ) amino ] pyridazin - 3 ( 2H ) - one hydrochloride , a novel phosphodiesterase ( PDE ) inhibitor synthesized as a potent vasodilatory and antiplatelet agent , is being developed for the treatment of intermittent claudication ( IC ) in patients with peripheral arterial disease . We assessed the efficacy of NT - 702 in an experimental IC model as compared with cilostazol and additionally investigated the pharmacological property in vitro and ex vivo . NT - 702 selectively inhibited PDE 3 ( IC ( 50 )= 0.179 and 0.260 nM for Q14432 REA and 3B ) more potently than cilostazol ( IC ( 50 )= 231 and 237 nM for Q14432 REA and 3B ) among recombinant human PDE 1 to PDE 6 . NT - 702 inhibited in vitro human platelet aggregation induced by various agonists ( IC ( 50 )= 11 to 67 nM ) and phenylephrine-induced rat aortic contraction ( IC ( 50 )= 24 nM ) . Corresponding results for cilostazol were 4.1 to 17 microM and 1.0 microM , respectively . NT - 702 ( 3 mg / kg or more ) significantly inhibited ex vivo rat platelet aggregation after a single oral dose . For cilostazol , 300 mg / kg was effective . In a rat femoral artery ligation model , NT - 702 at 5 and 10 mg / kg repeated oral doses twice a day ( P55957 REA ) for 13 days significantly improved the reduced walking distance while the lowered plantar surface temperature was improved at 2.5 mg / kg and more . DB01166 SUB also improved the walking distance and surface temperature at 300 mg / kg P55957 REA but significant difference was only observed for surface temperature on day 8 . These results suggest that NT - 702 can be expected to have therapeutic advantage for IC .

Genetic markers in the EET metabolic pathway are associated with outcomes in patients with aneurysmal subarachnoid hemorrhage . Preclinical studies show that epoxyeicosatrienoic acids ( EETs ) regulate cerebrovascular tone and protect against cerebral ischemia . We investigated the relationship between polymorphic genes involved in EET biosynthesis / metabolism , cytochrome P450 ( CYP ) eicosanoid levels , and outcomes in 363 patients with aneurysmal subarachnoid hemorrhage ( aSAH ) . Epoxyeicosatrienoic acids and dihydroxyeicosatetraenoic acid ( DHET ) cerebrospinal fluid ( P04141 REA ) levels , as well as acute outcomes defined by delayed cerebral ischemia ( P42126 REA ) or clinical neurologic deterioration ( CND ) , were assessed over 14 days . Long-term outcomes were defined by Modified Rankin Scale ( P59665 REA ) at 3 and 12 months . P10632 REA * 4 allele carriers had 44 % and 36 % lower mean EET and DHET P04141 REA levels ( P= 0.003 and P= 0.007 ) and were 2.2- and 2.5- fold more likely to develop P42126 REA and CND ( P= 0.039 and P= 0.041 ) , respectively . P34913 REA 55Arg , P51589 REA * 7 , P10632 REA * 1B , and P10632 REA g . 36785A allele carriers had lower EET and DHET P04141 REA levels . P10632 REA g . 25369T and P10632 REA g . 36755A allele carriers had higher EET levels . Patients with P10632 REA * 2C and P34913 REA 404del variants had worse long-term outcomes while those with P34913 REA 287Gln , P51589 REA * 7 , and P11712 REA g . 816G variants had favorable outcomes . Epoxyeicosatrienoic acid levels were associated with Fisher grade and unfavorable 3 - month outcomes . Dihydroxyeicosatetraenoic acids were not associated with outcomes . No associations passed Bonferroni multiple testing correction . These are the first clinical data demonstrating the association between the EET biosynthesis / metabolic pathway and the pathophysiology of aSAH .

FTY 720 induces apoptosis of chronic myelogenous leukemia cells via dual activation of O43521 REA and P55957 REA and overcomes various types of resistance to tyrosine kinase inhibitors . PP2A activator FTY 720 has been shown to possess the anti-leukemic activity for chronic myelogenous leukemia ( CML ) , however , the cell killing mechanism underlying its anti-leukemic activity has remained to be verified . We investigated the precise mechanisms underlying the apoptosis induction by FTY 720 , especially focusing on the roles of BH3 - only proteins , and the therapeutic potency of FTY 720 for CML . Enforced expression of either P10415 REA or the dominant-negative protein of Q13158 REA ( Q13158 REA . DN ) partly protected CML cells from apoptosis by FTY 720 , indicating the involvement of both cell extrinsic and intrinsic apoptosis pathways . FTY 720 activates pro-apoptotic BH3 - only proteins : O43521 REA , which is essential for apoptosis by P11274 REA - P00519 REA tyrosine kinase inhibitors ( TKIs ) , and P55957 REA , which accelerates the extrinsic apoptosis pathway . Gene knockdown of either O43521 REA or P55957 REA partly protected K562 cells from apoptosis by FTY 720 , but the extent of cell protection was not as much as that by overexpression of either P10415 REA or Q13158 REA . DN . Moreover , knockdown of both O43521 REA and P55957 REA did not provide additional protection compared with knockdown of only O43521 REA or P55957 REA , indicating that O43521 REA and P55957 REA complement each other in apoptosis by FTY 720 , especially when either is functionally impaired . FTY 720 can overcome TKI resistance caused by P00519 REA kinase domain mutations , dysfunction of O43521 REA resulting from gene deletion polymorphism , and galectin - 3 overexpression . In addition , DB05764 , a BH3 - mimetic , significantly augmented cell death induction by FTY 720 both in TKI-sensitive and - resistant leukemic cells . These results provide the rationale that FTY 720 , with its unique effects on O43521 REA and P55957 REA , could lead to new therapeutic strategies for CML .

Effective dasatinib uptake may occur without human organic cation transporter 1 ( O15245 REA ) : implications for the treatment of imatinib-resistant chronic myeloid leukemia . We have previously shown that imatinib uptake into chronic myeloid leukemia ( CML ) cells is dependent on human organic cation transporter 1 ( O15245 REA ; O15245 REA ) , and that low O15245 REA expression is an important determinant of clinical outcome to imatinib treatment . We hypothesized that dasatinib might be transported differently than imatinib , possibly accounting for its favorable effects in imatinib-resistant patients . ( 14 ) C-dasatinib uptake was greater in KCL 22 - transfected cells with pcDNA 3 - O15245 REA plasmid ( high O15245 REA - expressing cells ) than in control cells ( P = . 02 ) . However , hOCT inhibitors did not decrease dasatinib uptake into either control or primary cells , in contrast to their block on imatinib uptake . Dasa-tinib decreased the level of phosphorylated CrkL to 49.9 % in control and 40.3 % in high O15245 REA - expressing cells . Dasa-tinib efflux was investigated in confluent P08183 REA - transfected MDCKII cell monolayers . Both dasatinib and imatinib were transported from the basal to the apical layer , indicating that they were transported by P08183 REA , which was confirmed using the P08183 REA inhibitor PSC 833 ( P = . 001 and P < . 001 , respectively ) . Compared with imatinib , dasatinib achieved superior intracellular levels and P11274 REA - P00519 REA suppression even in cells with low or blocked O15245 REA . Efflux of dasatinib and imatinib appear similar via P08183 REA . Dasatinib may therefore offer an advantage over imatinib in patients with low O15245 REA expression .

A new algorithm for weekly phenprocoumon dose variation in a southern Brazilian population : role for P11712 REA , P08684 REA / 5 and Q9BQB6 genes polymorphisms . DB00946 MEN is widely used in prophylaxis and treatment of thromboembolic disorders . However , its pharmacokinetics and pharmacodynamics vary according to several genetic and non-genetic factors . DB00946 MENMAX DB00946 MEN metabolism is mediated by P11712 REA and CYP 3A enzymes . Moreover , Q9BQB6 is phenprocoumon target of action . Therefore , the aim of this study was to evaluate the association of single nucleotide polymorphisms ( SNPs ) in Q9BQB6 , P11712 REA , P08684 REA and P20815 REA genes with the variance of weekly phenprocoumon dose as well as to develop an algorithm for dose prediction based on genetic and environmental factors . A total of 198 patients with stable phenprocoumon dose , 81 % of European ancestry , were investigated . Genotypes were determined by allelic discrimination with TaqMan assays . Polymorphisms - 1639G > A and 1173C > T in Q9BQB6 and the presence of P11712 REA * 2 and / or P11712 REA * 3 are associated with lower doses . On the other hand , 3730G > A in Q9BQB6 gene is associated with higher doses . No association was found between P08684 REA * 1B , P20815 REA * 3 and P20815 REA * 6 polymorphisms . Among non-genetic factors , gender , height , age and use of captopril , omeprazole , simvastatin and β-blockers are associated with dose . Two algorithms were derived : one for the whole sample explained 42 % of dose variation and one for patients of European ancestry only which explained 46 % of phenprocoumon dose . The mean absolute difference between observed and predicted dose was low in both models ( 3.92 mg / week and 3.54 mg / week , for models 1 and 2 , respectively ) . However , more studies with other genes and environmental factors are needed to test and to improve the algorithm .