Discovery of novel 2-(3-phenylpiperazin-1-yl)-pyrimidin-4-ones as glycogen synthase kinase-3ß inhibitors.

We herein describe the results of further evolution of glycogen synthase kinase (GSK)-3ß inhibitors from our promising compounds containing a 2-phenylmorpholine moiety. Transformation of the morpholine moiety into a piperazine moiety resulted in potent GSK-3ß inhibitors. SAR studies focused on the phenyl moiety revealed that a 4-fluoro-2-methoxy group afforded potent inhibitory activity toward GSK-3ß. Based on docking studies, new hydrogen bonding between the nitrogen atom of the piperazine moiety and the oxygen atom of the main chain of Gln185 has been indicated, which may contribute to increased activity compared with that of the corresponding phenylmorpholine analogues. Effect of the stereochemistry of the phenylpiperazine moiety is also discussed.

2-(2-Phenylmorpholin-4-yl)pyrimidin-4(3H)-ones; a new class of potent, selective and orally active glycogen synthase kinase-3ß inhibitors.

A series of 2-(2-phenylmorpholin-4-yl)pyrimidin-4(3H)-ones was synthesized and examined for their inhibitory activity against glycogen synthase kinase-3ß (GSK-3ß). We found 21, 29 and 30 to possess potent in vitro GSK-3ß inhibitory activity with good in vitro PK profiles. 21 demonstrated significant decrease of tau phosphorylation after oral administration in mice and excellent PK profiles.

Association of denervation severity in the dermis with the development of mechanical allodynia and hyperalgesia in a murine model of postherpetic neuralgia.

BACKGROUND: Postherpetic neuralgia (PHN) is a common complication of herpes zoster and remains a challenging condition of neuropathic pain. Allodynia, a prominent feature of PHN, extends beyond the margins of the initial rash area. In the present study, we investigated the association between cutaneous denervation and the development of postherpetic allodynia and hyperalgesia by using a murine model of PHN. METHODS: Female C57BL/6j mice were used. Herpes simplex virus type-1 (HSV1) was inoculated on the unilateral shin, a region that is predominantly innervated by L3 dorsal root ganglion (DRG) neurons. After the zoster-like skin lesions healed, mice were classified by the presence of mechanical allodynia and hyperalgesia in the plantar aspect of the ipsilateral hindpaw. Scarred lumbar (innervated by L2-4 DRG neurons) and the ipsilateral plantar (innervated by L3-5 DRG neurons) skin sections were immunostained with an antibody against protein gene product (PGP)9.5. The number of PGP9.5-immunoreactive (IR) profiles in the epidermis and dermis were analyzed for quantification of cutaneous innervation. RESULTS: In the epidermis of the scarred lumbar skin, the intraindividual mean number of PGP9.5-IR profiles was significantly decreased in mice inoculated with HSV1. The intraindividual maximum and mean numbers of PGP9.5-IR profiles in the epidermis of the scarred skin were not significantly different between mice with and without postherpetic allodynia and hyperalgesia. In the dermis of the scarred lumbar skin, the intraindividual maximum and mean numbers of PGP9.5-IR profiles were significantly decreased in mice with postherpetic allodynia and hyperalgesia, but not in mice without these symptoms. The intraindividual minimum number of PGP9.5-IR profiles in the dermis and epidermis was significantly decreased by HSV1 inoculation. HSV1 inoculation significantly decreased the intraindividual mean number of PGP9.5-IR profiles in the epidermis, but not dermis, of the plantar skin on the inoculated side. CONCLUSIONS: The present results suggest that the severity of dermal denervation in the scarred skin is associated with the development of postherpetic allodynia and hyperalgesia that extend beyond the margins of the initial rash area. The decrease of epidermal nerve density in the scarred and stimulation skins may not be associated with postherpetic allodynia and hyperalgesia.

Converging evidence that sequence variations in the novel candidate gene MAP2K7 (MKK7) are functionally associated with schizophrenia.

Schizophrenia is a debilitating psychiatric disease with a strong genetic contribution, potentially linked to altered glutamatergic function in brain regions such as the prefrontal cortex (PFC). Here, we report converging evidence to support a functional candidate gene for schizophrenia. In post-mortem PFC from patients with schizophrenia, we detected decreased expression of MKK7/MAP2K7-a kinase activated by glutamatergic activity. While mice lacking one copy of the Map2k7 gene were overtly normal in a variety of behavioural tests, these mice showed a schizophrenia-like cognitive phenotype of impaired working memory. Additional support for MAP2K7 as a candidate gene came from a genetic association study. A substantial effect size (odds ratios: ~1.9) was observed for a common variant in a cohort of case and control samples collected in the Glasgow area and also in a replication cohort of samples of Northern European descent (most significant P-value: 3 × 10(-4)). While some caution is warranted until these association data are further replicated, these results are the first to implicate the candidate gene MAP2K7 in genetic risk for schizophrenia. Complete sequencing of all MAP2K7 exons did not reveal any non-synonymous mutations. However, the MAP2K7 haplotype appeared to have functional effects, in that it influenced the level of expression of MAP2K7 mRNA in human PFC. Taken together, the results imply that reduced function of the MAP2K7-c-Jun N-terminal kinase (JNK) signalling cascade may underlie some of the neurochemical changes and core symptoms in schizophrenia.

Orally active neurotrophin-enhancing agent protects against dysfunctions of the peripheral nerves in hyperglycemic animals.

Biological substances with neurotrophic activities, such as nerve growth factor (NGF) and monosialoganglioside GM1, have been considered as agents for diabetic peripheral neuropathy. Because recent studies have suggested that decreased availability of these substances might contribute to the pathogenesis of diabetic peripheral neuropathy, some clinical trials of NGF for diabetic peripheral neuropathy have been conducted and have led to mixed conclusions. The major reasons were its limited delivery to the nervous system and adverse effects induced by subcutaneous injection, which was necessary because NGF is a polypeptide. The current study investigates whether an orally active sialic acid derivative, MCC-257, has neuroprotective properties in diabetic peripheral nerves. MCC-257 augmented NGF activity in cultured dorsal root ganglia and PC12 (pheochromocytoma 12) cells. Treatment with MCC-257 elevated NGF levels in the sciatic nerve, accompanied by improvement in nerve conduction velocity in streptozotocin-induced diabetic animals. More importantly, MCC-257 ameliorated small fiber dysfunctions, including thermal hypoalgesia, substance P content, and histopathological innervation in the plantar skin of diabetic animals. Thus, the orally active neurotrophin enhancer provides a new option for the clinical treatment of diabetic peripheral neuropathy.

Neuropharmacological profile of a novel potential atypical antipsychotic drug Y-931 (8-fluoro-12-(4-methylpiperazin-1-yl)- 6H-[1]benzothieno[2,3-b][1,5] benzodiazepine maleate).

The neuropharmacological profile of Y-931, 8-fluoro-12- (4-methylpiperazin-1-yl)- 6H-[1]benzothieno [2,3-b][1,5]benzodiazepine maleate, was investigated in comparison with those of typical and claimed atypical antipsychotic drugs. Similar to clozapine and olanzapine, Y-931 interacted with multiple neurotransmitter receptors such as dopaminergic, serotonergic, alpha-adrenergic, muscarinic and histaminergic receptors. Y-931, as well as the other antipsychotics, was active in a dose-dependent manner in established tests which are indicative of potential antipsychotic activity such as inhibition of apomorphine-induced hyperactivity and suppression of conditioned avoidance responses, however, only Y-931 and clozapine were devoid of cataleptogenic potential. In models of N-methyl-D-aspartate (NMDA) receptor hypofunction, Y-931 demonstrated the most potent protective action against the dizocilpine-induced neurotoxicity (neuronal vacuolization) in the rat retrosplenial cortex ([Y-931 (ED(50); 0.20 mg/kg, p.o.), olanzapine (1.1), clozapine (5.7), risperidone (6.9), haloperidol (19)). Furthermore, Y-931 and clozapine, unlike the other antipsychotics used, reversed the dizocilpine-induced social deficits at the same doses at which their neuroprotective action was exhibited. The present results suggest that Y-931 may be a novel potential atypical antipsychotic drug with a low risk of extrapyramidal syndrome (EPS) and the property to ameliorate NMDA receptor hypofunction.