Combining olfactory test and motion analysis sensors in Parkinson's disease preclinical diagnosis: a pilot study.

OBJECTIVES: Preclinical diagnosis of Parkinson's disease (PD) is nowadays a topic of interest as the neuropathological process could begin years before the appearance of motor symptoms. Several symptoms, among them hyposmia, could precede motor features in PD. In the preclinical phase of PD, a subclinical reduction in motor skills is highly likely. In this pilot study, we investigate a step-by-step method to achieve preclinical PD diagnosis. MATERIAL AND METHODS: We used the IOIT (Italian Olfactory Identification Test) to screen a population of healthy subjects. We identified 20 subjects with idiopathic hyposmia. Hyposmic subjects underwent an evaluation of motor skills, at baseline and after 1 year, using motion analysis sensors previously created by us. RESULTS: One subject showed significant worsening in motor measurements. In this subject, we further conducted a dopaminergic challenge test monitored with the same sensors and, finally, he underwent [123 I]-FP/CIT (DaTscan) SPECT brain imaging. The results show that he is probably affected by preclinical PD. CONCLUSIONS: Our pilot study suggests that the combined use of an olfactory test and motor sensors for motion analysis could be useful for a screening of healthy subjects to identify those at a high risk of developing PD.

Antibiotics Prescriptions in the Neonatal Intensive Care Unit: How to Overcome Everyday Challenges.

Antimicrobial prescriptions in neonatal intensive care units (NICUs) represent a point of concern for the emergence of MDROs and for morbidity associated with prolonged antibiotic exposure (e.g., invasive candidiasis, necrotizing enterocolitis, and late-onset sepsis). Antimicrobial stewardship programs (ASPs) have shown to be a valuable tool for the prevention of resistance with the goals of optimizing clinical outcomes while decreasing unnecessary prescribing. The most frequent ASP strategies include the correct collection and interpretation of microbiological specimens, prescription of the narrowest-spectrum antibiotic appropriate for a particular case, and de-escalation or discontinuation of therapy in defined situations. A robust ASP requires everyday multidisciplinary collaboration between ID physicians, neonatologist, clinical pharmacists, clinical microbiologists, infection control professionals, hospital epidemiologists, and information services specialists. Education and clinical pathways (e.g., sepsis or surgical prophylaxis pathways) are an excellent starting point if followed by proactive interventions such as prospective audits and feedback and formulary restriction with prior antimicrobial authorization. The current review outlines the problems faced in NICU antimicrobial prescribing and presents various solutions from the literature.

PC1, a non-peptide PKR1-preferring antagonist, reduces pain behavior and spinal neuronal sensitization in neuropathic mice.

Peripheral neuropathy is characterized by abnormal pain responses triggered by the release of several mediators and neuronal hyperexcitability at the spinal cord level. Emerging evidence indicates that the enhanced activity of dorsal horn neurons requires communication with glia and microglia, cells that are physiologically involved in neuronal wellbeing. Prokineticins (PKs), which include PK1 and PK2, represent a novel family of chemokines characterized by a unique structural motif comprising five disulfide bonds. They are expressed in the peripheral and central nervous system. PKs bind two G protein coupled receptors, PKR1 and PKR2, and participate in the regulation of several biological processes, including pain sensation. This study aimed to investigate the anti-nociceptive effect of PC1, a non-peptide PKR1-preferring antagonist, in a mouse model of neuropathic pain. To do this, we assessed the activity of spinal cord nociceptive neurons as well as astrocyte and microglia phenotypes after repeated administration of PC1 in vivo. PC1 treatment strongly delayed the development of thermal hyperalgesia and tactile and mechanical allodynia. It also reduced spinal microglial and glial activation 8 days post injury in spared nerve injury (SNI) mice. Neuropathic mice showed an increased level of PK2 protein in the spinal cord, mostly in astrocytes. PC1 treatment completely reversed the increased responsiveness to mechanical stimuli, the decreased threshold of neuronal activation, and the increased spontaneous activity that were observed in nociceptive specific (NS) neurons of SNI mice.

Development and characterisation of novel fentanyl-delta opioid receptor antagonist based bivalent ligands.

BACKGROUND: Opioid tolerance is a limiting factor in chronic pain. Delta opioid peptide (DOP)(δ) receptor antagonism has been shown to reduce tolerance. Here, the common clinical mu opioid peptide (MOP)(µ) receptor agonist fentanyl has been linked to the DOP antagonist Dmt-Tic (2',6'-dimethyl-L-tyrosyl-1,2,3,4-tetrahydrisoquinoline-3-carboxylic acid) to create new bivalent compounds. METHODS: Binding affinities of bivalents(#9, #10, #11, #12 and #13) were measured in Chinese hamster ovary (CHO) cells expressing recombinant human MOP, DOP, Kappa opioid peptide (KOP)(κ) and nociceptin/orphanin FQ opioid peptide (NOP) receptors. Functional studies, measuring GTPγ[(35)S] or ß-arrestin recruitment, were performed in membranes or whole cells respectively expressing MOP and DOP. RESULTS: The new bivalents bound to MOP (pKi : #9:7.31; #10:7.58; #11:7.91; #12:7.94; #13:8.03) and DOP (#9:8.03; #10:8.16; #11:8.17; #12:9.67; #13:9.71). In GTPγ[(35)S] functional assays, compounds #9(pEC50:6.74; intrinsic activity:0.05) #10(7.13;0.34) and #11(7.52;0.27) showed weak partial agonist activity at MOP. Compounds #12 and #13, with longer linkers, showed no functional activity at MOP. In antagonist assays at MOP, compounds #9 (pKb:6.87), #10(7.55) #11(7.81) #12(6.91) and #13(7.05) all reversed the effects of fentanyl. At DOP, all compounds showed antagonist affinity (#9:6.85; #10:8.06; #11:8.11; #12:9.42; #13:9.00), reversing the effects of DPDPE ([D-Pen(2,5)]enkephalin). In ß-arrestin assays, compared with fentanyl (with response at maximum concentration (RMC):13.62), all compounds showed reduced ability to activate ß-arrestin (#9 RMC:1.58; #10:2.72; #11:2.40; #12:1.29; #13:1.58). Compared with fentanyl, the intrinsic activity was: #9:0.12; #10:0.20; #11:0.18; #12:0.09 and #13:0.12. CONCLUSIONS: The addition of a linker between fentanyl and Dmt-Tic did not alter the ability to bind to MOP and DOP, however a substantial loss in MOP functional activity was apparent. This highlights the difficulty in multifunctional opioid development.

Comparative cytogenetics of six Indo-Pacific moray eels (Anguilliformes: Muraenidae) by chromosomal banding and fluorescence in situ hybridization.

A comparative cytogenetic analysis, using both conventional staining techniques and fluorescence in situ hybridization, of six Indo-Pacific moray eels from three different genera (Gymnothorax fimbriatus, Gymnothorax flavimarginatus, Gymnothorax javanicus, Gymnothorax undulatus, Echidna nebulosa and Gymnomuraena zebra), was carried out to investigate the chromosomal differentiation in the family Muraenidae. Four species displayed a diploid chromosome number 2n = 42, which is common among the Muraenidae. Two other species, G. javanicus and G. flavimarginatus, were characterized by different chromosome numbers (2n = 40 and 2n = 36). For most species, a large amount of constitutive heterochromatin was detected in the chromosomes, with species-specific C-banding patterns that enabled pairing of the homologous chromosomes. In all species, the major ribosomal genes were localized in the guanine-cytosine-rich region of one chromosome pair, but in different chromosomal locations. The (TTAGGG)n telomeric sequences were mapped onto chromosomal ends in all muraenid species studied. The comparison of the results derived from this study with those available in the literature confirms a substantial conservation of the diploid chromosome number in the Muraenidae and supports the hypothesis that rearrangements have occurred that have diversified their karyotypes. Furthermore, the finding of two species with different diploid chromosome numbers suggests that additional chromosomal rearrangements, such as Robertsonian fusions, have occurred in the karyotype evolution of the Muraenidae.

Management of chronic constipation in general practice.

BACKGROUND: Chronic constipation is often diagnosed and treated by general practitioners (GPs). The aim of the study was to evaluate the management of constipation by a cohort of Italian GPs. METHODS: Over the course of 1 month, 41 GPs recorded tests and therapies suggested to patients complaining of chronic constipation. They were classified according to the Rome III criteria as constipated irritable bowel syndrome (C-IBS), functional constipation (FC), or "self-perceived constipation" (SPC) (not consistent with the Rome criteria). RESULTS: The most frequently prescribed tests for the 229 patients (147 FC, 50 C-IBS, 32 SPC) were routine blood tests (59.3 %), abdominal ultrasounds (37.2 %), thyroid function (36.7 %), fecal occult blood tests (36.7 %), and tumor markers (35 %). Patient sex and age, GP age, and whether the diagnosis was new influenced the GP's request, but FC, C-IBS, or SPC status did not. Dietary suggestions (81.9 %), fiber supplements (59.7 %), reassurance (50.9 %), and laxatives (30.5 %) were the most frequently prescribed treatments. Antispasmodics were more frequently suggested for C-IBS patients; dietary suggestions, fiber, and enemas were more frequently prescribed in SPC patients. Patient and GP age and whether the diagnosis was new influenced the GP's choice of treatment. CONCLUSIONS: The Rome III criteria do not influence diagnostic strategies and only slightly influence therapeutic strategies of GPs. Other factors (age, gender, new or old diagnosis) have more influence on GPs choice of investigations and treatment.

Racemic synthesis and solid phase peptide synthesis application of the chimeric valine/leucine derivative 2-amino-3,3,4-trimethyl-pentanoic acid.

The synthesis of non natural amino acid 2-amino-3,3,4-trimethyl-pentanoic acid (Ipv) ready for solid phase peptide synthesis has been developed. Copper (I) chloride Michael addition, followed by a Curtius rearrangement are the key steps for the lpv synthesis. The racemic valine/leucine chimeric amino acid was then successfully inserted in position 5 of neuropeptide S (NPS) and the diastereomeric mixture separated by reverse phase HPLC. The two diastereomeric NPS derivatives were tested for intracellular calcium mobilization using HEK293 cells stably expressing the mouse NPS receptor where they behaved as partial agonist and pure antagonist.

Pycnodysostosis: review and case report.

AIM: Aim of the present study was to present a case report of a patient suffering from pycnodysostosis and assess how it may manifest and affect the dental/ orthodontic treatment. METHODS: An 11-year-old patient who was diagnosed with pycnodysostosis at the age of 18 months, attended the orthodontics department requiring treatment for extensive carious lesions, periodontal disease and severe crowding. RESULTS: After an accurate radiographic, clinical and orthodontic assessment of the patient taking into consideration the severity of the condition and the patient's necessities, we have formulated a treatment plan, which was accepted by both the patient and parents. We took into consideration the risks and benefits of the options available and the requests of the patient. CONCLUSION: We have decided to opt for the extraction of teeth to relieve the crowding as this was impeding good oral hygiene and hence increasing the risk of caries and periodontal disease. Such patients must be placed under an oral hygiene prevention scheme, a treatment plan must be accurately designed and the patient must be constantly motivated.

Mortality rate and outcome factors in mixed cryoglobulinaemia: the impact of hepatitis C virus.

OBJECTIVES: Mixed cryoglobulinaemia (MC) is a chronic small-vessel vasculitis. Shortly after the discovery of hepatitis C virus (HCV) in 1989, an association between HCV infection and MC was being increasingly reported, suggesting the potential pathogenetic implication of HCV in most of the cases that had been previously diagnosed as essential MC. A number of studies have pointed out prognostic factors linked to mortality in this disorder. None of them, however, have clarified the impact of HCV discovery on the natural history of the disease. The aim of the present study was to evaluate mortality in MC after the discovery of HCV infection. METHODS: We retrospectively collected clinical and serological data in 70 unselected HCV-positive patients being followed up at our unit from 1990. Clinical and prognostic factors linked to poor outcome were evaluated. RESULTS: Chronic hepatitis, renal involvement, and intestinal vasculitis were the most frequent causes of death. CONCLUSION: Compared to other series, the outcome in our MC seemed to be better. Factors linked to a poor outcome were renal involvement, widespread vasculitis, male sex, and cryocrit.

Na+ mechanism of delta-opioid receptor induced protection from anoxic K+ leakage in the cortex.

Activation of delta-opioid receptors (DOR) attenuates anoxic K(+) leakage and protects cortical neurons from anoxic insults by inhibiting Na(+) influx. It is unknown, however, which pathway(s) that mediates the Na(+) influx is the target of DOR signal. In the present work, we found that, in the cortex, (1) DOR protection was largely dependent on the inhibition of anoxic Na(+) influxes mediated by voltage-gated Na(+) channels; (2) DOR activation inhibited Na(+) influx mediated by ionotropic glutamate N-methyl-D-aspartate (NMDA) receptors, but not that by non-NMDA receptors, although both played a role in anoxic K(+) derangement; and (3) DOR activation had little effect on Na(+)/Ca(2+) exchanger-based response to anoxia. We conclude that DOR activation attenuates anoxic K(+) derangement by restricting Na(+) influx mediated by Na(+) channels and NMDA receptors, and that non-NMDA receptors and Na(+)/Ca(2+) exchangers, although involved in anoxic K(+) derangement in certain degrees, are less likely the targets of DOR signal.

Assessment of prevalence and load of torquetenovirus viraemia in a large cohort of healthy blood donors.

OBJECTIVES: Torquetenovirus (TTV) is an emerging marker of functional immune competence with the potential to predict transplant-related adverse events. A large-scale epidemiological study was performed to understand how basal values vary in healthy individuals according to age and gender. METHODS: We tested plasma from 1017 healthy blood donors aged 18-69 years. The presence and load of TTV were determined by a real-time PCR assay. A sub-cohort of 384 donors was tested for anti-cytomegalovirus IgG antibodies, and 100 participants were also tested for TTV viraemia on a paired whole blood sample. RESULTS: The overall prevalence of TTV was 65% (657/1017) with a mean (±SD) growth of 5 ± 4% every 10 years of age increase, but stably higher in males (465/690, 67%) than in females (192/327, 59%). Mean (±SD) TTV load was 2.3 ± 0.7 Log copies/mL with no sex difference. TTV viraemia showed modest increases along 10-year age intervals (mean ± SD: 0.3 ± 0.1). TTV viraemia in donors sampled 2 years later remained stable (mean ± SD: 2.3 ± 0.8 versus 2.2 ± 0.7 Log copies between samples). Twenty-six per cent (9/34) of blood donors with TTV-negative plasma scored positive when whole blood was tested, and the donors with positive plasma showed a mean (±SD) 1.4 ± 0.5 Log increase in copy numbers when whole blood was tested. CONCLUSIONS: This study establishes the mean value of TTV viraemia in plasma in healthy blood donors and suggests that ageing causes only minimal increases in TTV viraemia.

A ZZ-ZW sex chromosome system in the finless eel Dalophis imberbis (Anguilliformes, Ophichtidae).

The karyotype of the finless eel Dalophis imberbis was investigated by conventional (C and replication banding, CMA(3) fluorescence) and molecular (FISH with 45S rDNA probe) techniques. The diploid chromosome number was 2n = 46 and the karyotype consisted of four pairs of meta-submetacentric and 18 pairs of subtelo-acrocentric autosomes and a pair of sex chromosomes heteromorphic in females, composed by a large subtelocentric Z, and a medium sized acrocentric W chromosome; in males this pair was composed by two large subtelocentric ZZ chromosomes. Multiple NORs have been localized by FISH and have been found to be CMA(3) positive; one of the NORs was located on the W chromosome and it was found transcriptionally active by silver staining. The Z chromosome contained distinct intercalar C-positive heterochromatin and W was almost completely heterochromatic. Our report contributes to the knowledge to the cytotaxonomy of Anguilliformes where differentiated sex chromosomes are reported in about a quarter of the species: both male and female heterogamety as well as a multiple chromosome system have been reported. Moreover, this is the first anguilliform species in which multiple NORs have been reported.

Perspectives of protein kinase C (PKC) inhibitors as anti-cancer agents.

Although the role of serine/threonine protein kinase C (PKC) in malignant transformation is known from decades, an anti-PKC based approach in cancer therapy was hampered for the difficulties in developing pharmacological compounds able to selectively inhibit specific PKC isoforms. In this review, the role of PKC-epsilon and PKC-delta in promoting and counteracting tumor progression in different types of cancer, respectively, will be discussed in relationship with promising therapeutic perspectives based either on small molecule inhibitors or on natural compounds. Among a myriad of molecules able to modulate PKC activity, we will focus on the role of the enzastaurin and briostatin-1, which already entered clinical trials for several human cancers.

Simultaneous targeting of multiple opioid receptors: a strategy to improve side-effect profile.

Opioid receptors are currently classified as mu (mu: mOP), delta (delta: dOP), kappa (kappa: kOP) with a fourth related non-classical opioid receptor for nociceptin/orphainin FQ, NOP. Morphine is the current gold standard analgesic acting at MOP receptors but produces a range of variably troublesome side-effects, in particular tolerance. There is now good laboratory evidence to suggest that blocking DOP while activating MOP produces analgesia (or antinociception) without the development of tolerance. Simultaneous targeting of MOP and DOP can be accomplished by: (i) co-administering two selective drugs, (ii) administering one non-selective drug, or (iii) designing a single drug that specifically targets both receptors; a bivalent ligand. Bivalent ligands generally contain two active centres or pharmacophores that are variably separated by a chemical spacer and there are several interesting examples in the literature. For example linking the MOP agonist oxymorphone to the DOP antagonist naltrindole produces a MOP/DOP bivalent ligand that should produce analgesia with reduced tolerance. The type of response/selectivity produced depends on the pharmacophore combination (e.g. oxymorphone and naltrindole as above) and the space between them. Production and evaluation of bivalent ligands is an emerging field in drug design and for anaesthesia, analgesics that are designed not to be highly selective morphine-like (MOP) ligands represents a new avenue for the production of useful drugs for chronic (and in particular cancer) pain.

Neuropeptide S is a stimulatory anxiolytic agent: a behavioural study in mice.

BACKGROUND AND PURPOSE: Neuropeptide S (NPS) was recently identified as the endogenous ligand of an orphan receptor, now referred to as the NPS receptor. In vivo, NPS produces a unique behavioural profile by increasing wakefulness and exerting anxiolytic-like effects. In the present study, we further evaluated the effects of in vivo supraspinal NPS in mice. EXPERIMENTAL APPROACH: Effects of NPS, injected intracerebroventricularly (i.c.v.), on locomotor activity (LA), righting reflex (RR) recovery and on anxiety states (measured with the elevated plus maze (EPM) and stress-induced hyperthermia (SIH) tests) were assessed in Swiss mice. KEY RESULTS: NPS (0.01-1 nmol per mouse) caused a significant increase in LA in naive mice, in mice habituated to the test cages and in animals sedated with diazepam (5 mg kg(-1)). In the RR assay, NPS dose dependently reduced the proportion of animals losing the RR in response to diazepam (15 mg kg(-1)) and their sleeping time. In the EPM and SIH test, NPS dose dependently evoked anxiolytic-like effects by increasing the time spent by animals in the open arms and reducing the SIH response, respectively. CONCLUSIONS AND IMPLICATIONS: We provide further evidence that NPS acts as a novel modulator of arousal and anxiety-related behaviours by promoting a unique pattern of effects: stimulation associated with anxiolysis. Therefore, NPS receptor ligands may represent innovative drugs for the treatment of sleep and anxiety disorders.

Different perception of chronic constipation between patients and gastroenterologists.

BACKGROUND: There is a certain number of subjects that consider themselves to be constipated (self diagnosed constipation; SDC). The Rome Criteria separate FC from IBS-C, but some SDC patients do not meet the Rome criteria (no Rome Constipation; NRC). Our aims were to evaluate the percentage of SDC subjects with a diagnosis of FC and IBS-C and to compare demographic and clinical features, symptoms, and quality of life in the different SDC groups (FC, IBS-C, NRC). METHODS: During a 2-month period, 934 patients and 980 accompanying persons (AP) were asked to complete a survey. The presence of FC or IBS-C was assessed. SDC subjects were invited to record the stool consistency (Bristol scale) and to fill in the Constipation Severity Index (CSI), obstructed defecation syndrome (ODS) and patient assessment of constipation-quality of life (PAC-QoL). The use of laxatives and enemas was evaluated. KEY RESULTS: The probability of the ROME III criteria being present was higher in SDC compared with no-SDC (OR 20.5). NRC was present in 13.5% of the SDC. In the patients' group the agreement between a diagnosis of Rome III and SDC was good (K 0.62), whereas in the AP it was moderate (K 0.56). NRC showed lower mean values of ODS, CSI and PAC-QoL, higher Bristol scale and a lower use of laxatives and enemas compared to IBS-C and FC. No differences were found between IBS-C and FC. CONCLUSIONS AND INFERENCES: The Rome III criteria identify subjects with a greater clinical impact, but separation of FC and IBS-C does not seem justified.

In vitro and in vivo characterization of the bifunctional µ and δ opioid receptor ligand UFP-505.

BACKGROUND AND PURPOSE: Targeting more than one opioid receptor type simultaneously may have analgesic advantages in reducing side-effects. We have evaluated the mixed µ opioid receptor agonist/ δ opioid receptor antagonist UFP-505 in vitro and in vivo. EXPERIMENTAL APPROACH: We measured receptor density and function in single µ, δ and µ /δ receptor double expression systems. GTPγ35 S binding, cAMP formation and arrestin recruitment were measured. Antinociceptive activity was measured in vivo using tail withdrawal and paw pressure tests following acute and chronic treatment. In some experiments, we collected tissues to measure receptor densities. KEY RESULTS: UFP-505 bound to µ receptors with full agonist activity and to δ receptors as a low efficacy partial agonist At µ, but not δ receptors, UFP-505 binding recruited arrestin. Unlike morphine, UFP-505 treatment internalized µ receptors and there was some evidence for internalization of δ receptors. Similar data were obtained in a µ /δ receptor double expression system. In rats, acute UFP-505 or morphine, injected intrathecally, was antinociceptive. In tissues harvested from these experiments, µ and δ receptor density was decreased after UFP-505 but not morphine treatment, in agreement with in vitro data. Both morphine and UFP-505 induced significant tolerance. CONCLUSIONS AND IMPLICATIONS: In this study, UFP-505 behaved as a full agonist at µ receptors with variable activity at δ receptors. This bifunctional compound was antinociceptive in rats after intrathecal administration. In this model, dual targeting provided no advantages in terms of tolerance liability. LINKED ARTICLES: This article is part of a themed section on Emerging Areas of Opioid Pharmacology. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.14/issuetoc.

Secondary solid cancer following hematopoietic cell transplantation in patients with thalassemia major.

Hematopoietic cell transplant (HCT) recipients have a substantial risk of developing secondary solid cancers (SSCs). The aim of this retrospective study was to compare the incidence of SSC in a monocentric cohort of thalassemia major (TM) patients (n=122) who received HCT versus an hematopoietic cell donor monocentric cohort (n=122) and versus a large multicenter cohort of age- and sex-matched TM patients (n=244) who received conventional therapy. With a median follow-up of 24 years, 8 transplanted patients were diagnosed with SSC at a median of 18 years after HCT and at a median age of 33 years. Three patients died of cancer progression and 5 are living after a follow-up ranging from 10 months to 16 years after SSC diagnosis. The 30-year cumulative incidence of developing SSC was 13.24%. The occurrence of solid cancers in the hematopoietic cell donor cohort was limited to only one case for a significantly lower cumulative incidence (3.23%, P=0.02) and to 3 cases in the cohort of nontransplant patients for a significantly lower cumulative incidence (1.32%, P=0.005). This study shows that the magnitude of increased risk of SST is fourfold to sixfold for patients treated with HCT as compared with hematopoietic cell donors and nontransplant patients.

Serum OPG and RANKL levels before and after intravenous bisphosphonate treatment in Paget's disease of bone.

Paget's disease of bone (PDB) is a focal disorder of bone remodeling characterized by increased osteoclast-mediated bone resorption. Even though increasing evidence indicates enhanced nuclear factor-kB (NF-kB) signaling as a common mechanism involved in PDB and other related disorders, few studies investigated circulating osteoprotegerin (OPG) and receptor of activator of NF-kB-ligand (RANKL) levels in PDB patients. In this study we explored the relationships between OPG or RANKL levels and bone turnover markers in a group of patients with PDB, before and after intravenous bisphosphonate treatment (pamidronate 60 mg). Both OPG and RANKL were markedly elevated in PDB patients with respect to control groups (healthy or osteoporotic postmenopausal women and elderly men) and were positively associated with bone turnover markers. Higher levels of these cytokines were observed in polyostotic than monostotic PDB cases. The ratio between RANKL and OPG was more than 3-fold higher in PDB patients than in controls. Interestingly, in the group of patients treated with pamidronate, we found an increase in OPG levels that become statistically significant after 3 and 6 months from treatment. A trend toward a decrease in RANKL levels after treatment was also observed. The RANKL/OPG ratio was significantly reduced after 3 and 6 months of therapy. In contrast, in patients classified as non-responders, OPG and RANKL levels after pamidronate infusion did not significantly differ with respect to pre-treatment values. Thus, the positive effect of amino bisphosphonates in the treatment of PDB may be due to either direct or indirect suppression of RANKL-induced bone resorption through decreased RANKL and increased OPG production.

In vitro and in vivo pharmacological profile of UFP-512, a novel selective delta-opioid receptor agonist; correlations between desensitization and tolerance.

BACKGROUND AND PURPOSE: Delta-opioid receptors (DOP receptors) could represent a novel target in the treatment of depressive disorders. To explore this new field of interest, the development of highly selective DOP receptor agonists is essential. UFP-512 [H-Dmt-Tic-NH-CH(CH2-COOH)-Bid], was recently shown to behave in vitro as a selective and potent DOP receptor agonist and to promote antidepressant- and anxiolytic-like effects in vivo (Vergura et al., 2007). Here, we have characterized the pharmacological properties of UFP-512 and established a link between desensitization and tolerance. EXPERIMENTAL APPROACH: Studies were performed in the human neuroblastoma SK-N-BE cells to establish i) binding parameters for UFP-512 ii) signalling pathways activated after acute and chronic treatment iii) regulation (phosphorylation and trafficking) of human DOP (hDOP) receptors after sustained activation by UFP-512. In vivo, we studied UFP-512-induced antidepressant-like effects after acute or chronic treatment in the mouse forced swimming test. KEY RESULTS: In vitro, UFP-512 was a high affinity agonist for DOP receptors. While UFP-512 induced marked phosphorylation of DOP receptors on Ser363, we observed a low desensitization of the cAMP pathway, associated with receptor endocytosis and recycling without any reduction on extracellular signal-regulated protein kinase 1/2 activation. In vivo, acute administration of UFP-512 produced an antidepressant-like effect, without any sign of tolerance after chronic administration. CONCLUSIONS AND IMPLICATIONS: There was a correlation between weak desensitization, significant internalization and recycling of the human DOP receptors and lack of tolerance to UFP-512. This suggests that this compound would be a promising drug prototype for exploring innovative treatments for mood disorders.