Antonio Ferrer-Montiel

Publications of Antonio Ferrer-Montiel

• TRPV1 modulators: structure-activity relationships using a rational combinatorial approach.

  Authors: Laura Zaccaro, M Teresa García-López, Rosario González-Muñiz, Carolina García-Martínez, Antonio Ferrer-Montiel, Fernando Albericio, Miriam Royo

  Bioorganic & medicinal chemistry letters. 06/2011; 21(12):3541-5.

  A discrete library of linear and hydantoin-containing dipeptide derivatives, based on the Lys-Trp(Nps) scaffold, was prepared by solid-phase synthesis. SAR studies indicated that potency for TRPV1A discrete library of linear and hydantoin-containing dipeptide derivatives, based on the Lys-Trp(Nps) scaffold, was prepared by solid-phase synthesis. SAR studies indicated that potency for TRPV1 blockade and selectivity towards NMDA is mainly dictated by the side-chain length and the basic nature of α, ω-groups in the N-terminal residue. The 2-Nps moiety at position 2 of Trp indole ring is preferred over the 2-pyridine one.

• Estrogen destabilizes microtubules through an ion-conductivity-independent TRPV1 pathway.

  Authors: Chandan Goswami, Julia Kuhn, Olayinka A Dina, Gregorio Fernández-Ballester, Jon D Levine, Antonio Ferrer-Montiel, Tim Hucho

  Journal of neurochemistry. 06/2011; 117(6):995-1008.

  Recently, we described estrogen and agonists of the G-protein coupled estrogen receptor GPR30 to induce protein kinase C (PKC)ε-dependent pain sensitization. PKCε phosphorylates the ion channelRecently, we described estrogen and agonists of the G-protein coupled estrogen receptor GPR30 to induce protein kinase C (PKC)ε-dependent pain sensitization. PKCε phosphorylates the ion channel transient receptor potential, vanilloid subclass I (TRPV1) close to a novel microtubule-TRPV1 binding site. We now modeled the binding of tubulin to the TRPV1 C-terminus. The model suggests PKCε phosphorylation of TRPV1-S800 to abolish the tubulin-TRPV1 interaction. Indeed, in vitro PKCε phosphorylation of TRPV1 hindered tubulin-binding to TRPV1. In vivo, treatment of sensory neurons and F-11 cells with estrogen and the GPR30 agonist, G-1, resulted in microtubule destabilization and retraction of microtubules from filopodial structures. We found estrogen and G-1 to regulate the stability of the microtubular network via PKC phosphorylation of the PKCε-phosphorylation site TRPV1-S800. Microtubule disassembly was not, however, dependent on TRPV1 ion conductivity. TRPV1 knock-down in rats inverted the effect of the microtubule-modulating drugs, Taxol and Nocodazole, on estrogen-induced and PKCε-dependent mechanical pain sensitization. Thus, we suggest the C-terminus of TRPV1 to be a signaling intermediate downstream of estrogen and PKCε, regulating microtubule-stability and microtubule-dependent pain sensitization.

• Membrane-tethered peptides patterned after the TRP domain (TRPducins) selectively inhibit TRPV1 channel activity.

  Authors: Pierluigi Valente, Asia Fernández-Carvajal, María Camprubí-Robles, Ana Gomis, Susana Quirce, Félix Viana, Gregorio Fernández-Ballester, José M González-Ros, Carlos Belmonte, Rosa Planells-Cases, Antonio Ferrer-Montiel

  FASEB journal : official publication of the Federation of American Societies for Experimental Biology. 02/2011; 25(5):1628-40.

  The transient receptor potential vanilloid 1 (TRPV1) channel is a thermosensory receptor implicated in diverse physiological and pathological processes. The TRP domain, a highly conserved region inThe transient receptor potential vanilloid 1 (TRPV1) channel is a thermosensory receptor implicated in diverse physiological and pathological processes. The TRP domain, a highly conserved region in the C terminus adjacent to the internal channel gate, is critical for subunit tetramerization and channel gating. Here, we show that cell-penetrating, membrane-anchored peptides patterned after this protein domain are moderate and selective TRPV1 antagonists both in vitro and in vivo, blocking receptor activity in intact rat primary sensory neurons and their peripheral axons with mean decline time of 30 min. The most potent lipopeptide, TRP-p5, blocked all modes of TRPV1 gating with micromolar efficacy (IC(50)<10 μM), without significantly affecting other thermoTRP channels. In contrast, its retrosequence or the corresponding sequences of other TRPV channels did not alter TRPV1 channel activity (IC(50)>100 μM). TRP-p5 did not affect the capsaicin sensitivity of the vanilloid receptor. Our data suggest that TRP-p5 interferes with protein-protein interactions at the level of the TRP domain that are essential for the "conformational" change that leads to gate opening. Therefore, these palmitoylated peptides, which we termed TRPducins, are noncompetitive, voltage-independent, sequence-specific TRPV1 blockers. Our findings indicate that TRPducin-like peptides may embody a novel molecular strategy that can be exploited to generate a selective pharmacological arsenal for the TRP superfamily of ion channels.

• Complex regulation of TRPV1 and related thermo-TRPs: implications for therapeutic intervention.

  Authors: Rosa Planells-Cases, Pierluigi Valente, Antonio Ferrer-Montiel, Feng Qin, Arpad Szallasi

  Advances in experimental medicine and biology. 01/2011; 704:491-515.

  The capsaicin receptor TRPV1 (Transient Receptor Potential, Vanilloid family member 1), the founding member of the heat-sensitive TRP ("thermo-TRP") channel family, plays a pivotal role in painThe capsaicin receptor TRPV1 (Transient Receptor Potential, Vanilloid family member 1), the founding member of the heat-sensitive TRP ("thermo-TRP") channel family, plays a pivotal role in pain transduction. There is mounting evidence that TRPV1 regulation is complex and is manifest at many levels, from gene expression through post-translational modification and formation of receptor heteromers to subcellular compartmentalization and association with regulatory proteins. These mechanisms are believed to be involved both in disease-related changes in TRPV1 expression, and the long-lasting refractory state, referred to as "desensitization", that follows TRPV1 agonist treatment. The signaling cascades that regulate TRPV1 and related thermo-TRP channels are only beginning to be understood. Here we review our current knowledge in this rapidly changing field. We propose that the complex regulation of TRPV1 may be exploited for therapeutic purposes, with the ultimate goal being the development of novel, innovative agents that target TRPV1 in diseased, but not healthy, tissues. Such compounds are expected to be devoid of the side-effects (e.g. hyperthermia and impaired noxious heat sensation) that plague the clinical use of existing TRPV1 antagonists.

• Role of the transient receptor potential vanilloid 1 in inflammation and sepsis.

  Authors: Isabel Devesa, Rosa Planells-Cases, Gregorio Fernández-Ballester, José Manuel González-Ros, Antonio Ferrer-Montiel, Asia Fernández-Carvajal

  Journal of inflammation research. 01/2011; 4:67-81.

  The transient receptor potential vanilloid 1 (TRPV1) is a thermoreceptor that responds to noxious temperatures, as well as to chemical agonists, such as vanilloids and protons. In addition, itsThe transient receptor potential vanilloid 1 (TRPV1) is a thermoreceptor that responds to noxious temperatures, as well as to chemical agonists, such as vanilloids and protons. In addition, its channel activity is notably potentiated by proinflammatory mediators released upon tissue damage. The TRPV1 contribution to sensory neuron sensitization by proalgesic agents has signaled this receptor as a prime target for analgesic and anti-inflammatory drug intervention. However, TRPV1 antagonists have notably failed in clinical and preclinical studies because of their unwanted side effects. Recent reports have unveiled previously unrecognized anti-inflammatory and protective functions of TRPV1 in several diseases. For instance, this channel has been suggested to play an anti-inflammatory role in sepsis. Therefore, the use of potent TRPV1 antagonists as a general strategy to treat inflammation must be cautiously considered, given the deleterious effects that may arise from inhibiting the population of channels that have a protective function. The use of TRPV1 antagonists may be limited to treating those pathologies where enhanced receptor activity contributes to the inflamed state. Alternatively, therapeutic paradigms, such as reduction of inflammatory-mediated increase of receptor expression in the cell surface, may be a better strategy to prevent abrogation of the TRPV1 subpopulation involved in anti-inflammatory and protective processes.

• Solid-phase synthesis of new Trp(Nps)-containing dipeptide derivatives as TRPV1 channel blockers.

  Authors: Ma Jesús Pérez de Vega, Ma Teresa García-López, Laura Zaccaro, Miriam Royo, Fernando Albericio, Asia Fernández-Carvajal, Antonio Ferrer-Montiel, Rosario González-Muñiz

  Molecules (Basel, Switzerland). 07/2010; 15(7):4924-33.

  Trp(Nps)-Lys-NH(2) derivatives, bearing alkyl or guanidine groups either at the N-terminus or on the Lys side-chain or at both positions were conveniently prepared on solid-phase and evaluated asTrp(Nps)-Lys-NH(2) derivatives, bearing alkyl or guanidine groups either at the N-terminus or on the Lys side-chain or at both positions were conveniently prepared on solid-phase and evaluated as TRPV1 channel antagonists.

• Rab4 interacts with the human P-glycoprotein and modulates its surface expression in multidrug resistant K562 cells.

  Authors: Clotilde Ferrándiz-Huertas, Asia Fernández-Carvajal, Antonio Ferrer-Montiel

  International journal of cancer. Journal international du cancer. 03/2010; 128(1):192-205.

  P-glycoprotein (P-gp) is a plasma membrane glycoprotein that has been signaled as a primary cause of multidrug resistance (MDR) in tumors. We performed a yeast 2-hybrid screen using the C-terminalP-glycoprotein (P-gp) is a plasma membrane glycoprotein that has been signaled as a primary cause of multidrug resistance (MDR) in tumors. We performed a yeast 2-hybrid screen using the C-terminal domain of P-gp and identified 2 small GTPases involved in vesicular trafficking, Rab4 and Rab14, which complex with P-gp. The overexpression of GFP-Rab4, either transiently or stably, but not of Rab14, in K562ADR cells decreased the presence of P-gp in the cell surface. As a result, expression of this GTPase reduced the MDR phenotype of K562ADR cells, by augmenting the intracellular accumulation of daunomycin (DNM). This effect was mimicked by the constitutively active Rab4Q72L mutant, but not by the dominant negative Rab4S27N mutant. Rab4 regulated excocytotic P-gp trafficking to the plasma membrane from intracellular compartments, and this modulation required the interaction of both proteins and the GTPase activity. Noteworthy, K562ADR cells exhibited a significant reduction of Rab4 levels, but not of other Rab GTPases, as compared with the sensitive parental cell line, suggesting that the development of the MDR phenotype in these cells involves upregulation of P-gp and a concomitant downregulation of proteins that regulate its surface expression. Attenuation of endogenous Rab4 levels in K562ADR by RNA interference enhanced the expression of P-gp in the cell surface, and reduced the uptake of DNM. Accordingly, these findings substantiate the notion that modulation of the temporal and spatial distribution of P-gp in cancer cells may be a valid therapeutic strategy to alleviate the MDR phenotype, and signal to Rab4 as a potential target.

• TRPA1 modulators in preclinical development.

  Authors: Félix Viana, Antonio Ferrer-Montiel

  Expert opinion on therapeutic patents. 12/2009; 19(12):1787-99.

  BACKGROUND: Transient receptor potential ankyrin 1 (TRPA1) has been revealed as a pivotal molecular entity in sensory biology, especially as a sensor of chemical irritants present in foods,BACKGROUND: Transient receptor potential ankyrin 1 (TRPA1) has been revealed as a pivotal molecular entity in sensory biology, especially as a sensor of chemical irritants present in foods, atmospheric pollutants and neurotoxic compounds. In addition, this channel appears responsible for detecting physical signals such as noxious cold and mechanical forces. OBJECTIVES: There is mounting evidence that TRPA1 is involved in the pathophysiology of several diseases, and directly contributes to the cold and mechanical hyperalgesia present in inflammatory and neuropathic states. Therefore, TRPA1 is an important therapeutic target for drug development. Intriguingly, however, the number of receptor antagonists reported thus far is notably low, as compared with the large number of receptor agonists. Nonetheless, known TRPA1 antagonists display very promising in vivo activity against mechanical hypersensitivity and cold hyperalgesia, although at therapeutic doses that are still high for drug development. A significant effort is being pursued using medicinal chemistry programs to modify the initial scaffolds for evolving lead compounds for preclinical and clinical assays. CONCLUSION: It is anticipated that this field will blossom in the near future, and the number and therapeutic indexes of new antagonists will be significantly improved. Furthermore, it will not be surprising if TRPA1 agonists also have some therapeutic potential, akin to capsaicin.

• Differential role of the menthol-binding residue Y745 in the antagonism of thermally gated TRPM8 channels.

  Authors: Annika Malkia, Maria Pertusa, Gregorio Fernandez-Ballester, Antonio Ferrer-Montiel, Felix Viana

  Molecular pain. 11/2009; 5(1):62.

  ABSTRACT: BACKGROUND: TRPM8 is a non-selective cation channel that belongs to the melastatin subfamily of the transient receptor potential (TRP) ion channels. TRPM8 is activated by voltage, cold andABSTRACT: BACKGROUND: TRPM8 is a non-selective cation channel that belongs to the melastatin subfamily of the transient receptor potential (TRP) ion channels. TRPM8 is activated by voltage, cold and cooling compounds such as menthol. Despite its essential role for cold temperature sensing in mammals, the pharmacology of TRPM8 is still in its infancy. Recently, tyrosine 745 (Y745) was identified as a critical residue for menthol sensitivity of the channel. In this report, we study the effect of mutating this residue on the action of several known TRPM8 antagonists: BCTC, capsazepine, SKF96365, and clotrimazole as well as two new inhibitor candidates, econazole and imidazole. RESULTS: We show that Y745 at the menthol binding site is critical for inhibition mediated by SKF96365 of cold- and voltage-activated TRPM8 currents. In contrast, the inhibition by other antagonists was unaffected by the mutation (BCTC) or only partially reduced (capsazepine, clotrimazole, econazole), suggesting that additional binding sites exists on the TRPM8 channel from where the inhibitors exert their negative modulation. Indeed, a molecular docking model implies that menthol and SKF96365 interact readily with Y745, while BCTC is unable to bind to this residue. CONCLUSIONS: In summary, we identify structural elements on the TRPM8 channel that are critical for the action of channel antagonists, providing valuable information for the future design of new, specific modulator compounds.

• Synthesis of a Positional Scanning Library of Pentamers of N-Alkylglycines Assisted by Microwave Activation and Validation via the Identification of Trypsin Inhibitors.

  Authors: Joaquim Messeguer, Nuria Cortés, Nuria García-Sanz, Gloria Navarro-Vendrell, Antonio Ferrer-Montiel, Angel Messeguer

  Journal of combinatorial chemistry. 11/2008;

  A positional scanning library of 625 N-alkylglycine pentamers has been synthesized on solid-phase, employing a set of 10 commercially available primary amines as a source of chemical diversity. TheA positional scanning library of 625 N-alkylglycine pentamers has been synthesized on solid-phase, employing a set of 10 commercially available primary amines as a source of chemical diversity. The iterative synthetic steps were carried out in tea bags and accelerated by using microwave assisted organic synthesis (MAOS). The reactivity study of the primary amines used as diversity sources led to determine their relative reactivity values and equireactivity factors, which were applied to the library synthesis to ensure comparable concentrations of all final oligomers in the mixtures. This library was validated by the screening, deconvolution, and identification of trypsin inhibitors. These compounds are of potential interest for controlling the intracellular transport of TRPV1 channel.

• Identification of molecular determinants of channel gating in the transient receptor potential box of vanilloid receptor I.

  Authors: Pierluigi Valente, Nuria García-Sanz, Ana Gomis, Asia Fernández-Carvajal, Gregorio Fernández-Ballester, Félix Viana, Carlos Belmonte, Antonio Ferrer-Montiel

  The FASEB journal : official publication of the Federation of American Societies for Experimental Biology. 07/2008;

  Transient receptor potential vanilloid receptor subtype I (TRPV1) is an ion channel gated by physical and chemical stimuli that belongs to the TRPV protein family. TRPV receptors contain a highlyTransient receptor potential vanilloid receptor subtype I (TRPV1) is an ion channel gated by physical and chemical stimuli that belongs to the TRPV protein family. TRPV receptors contain a highly conserved, 6-mer segment near the channel gate, known as the TRP box, whose function remains unknown. Here, we performed an alanine scanning mutagenesis of the TRP box of TRPV1 (IWKLQR) and found that mutation of this motif affected channel gating by raising the free energy of channel activation. Functional characterization of TRPV1 mutants showed that substitution of I696, W697, and R701 by alanine severely affected voltage- and heat-dependent activation and notably reduced the capsaicin responsiveness and tachyphylaxia, while mutation of K698, L699, and Q700 had minor effects. In addition, mutation of I696 to alanine promoted a strong outward rectification at negative membrane potentials, and slowed the kinetics of channel activation. Taken together, our findings suggest that modification of I696, W697, and R701 to alanine altered channel function by affecting events downstream of the initial stimuli-sensing step and imply that intersubunit interactions within the TRP box play an important role in TRPV1 gating.-Valente, P., García-Sanz, N., Gomis, A., Fernández-Carvajal, A., Fernández-Ballester, G., Viana, F., Belmonte, C., and Ferrer-Montiel, A. Identification of molecular determinants of channel gating in the transient receptor potential box of vanilloid receptor I.

• Design and synthesis of indole-based peptoids as potent noncompetitive antagonists of transient receptor potential vanilloid 1.

  Authors: Martina Quintanar-Audelo, Asia Fernández-Carvajal, Wim Van Den Nest, Cristina Carreño, Antonio Ferrer-Montiel, Fernando Albericio

  Journal of medicinal chemistry. 12/2007; 50(24):6133-43.

  The vanilloid receptor subunit 1, or transient receptor potential vanilloid 1 (TRPV1), integrates physical and chemical stimuli in the peripheral nervous system, playing a key role in inflammatoryThe vanilloid receptor subunit 1, or transient receptor potential vanilloid 1 (TRPV1), integrates physical and chemical stimuli in the peripheral nervous system, playing a key role in inflammatory pain. Identification of potent TRPV1 antagonists is thus an important goal of current neuropharmacology. Herein, we describe the solid-phase synthesis of a series of indole-based peptoids (N-alkylglycines) and the biological activity of the peptoids as novel TRPV1 antagonists. The potency and selectivity of the compounds were determined by electrophysiological recordings in Xenopus oocytes. The most potent and selective noncompetitive TRPV1 antagonist of the series, compound 7, represents an interesting pharmacophoric structure for analgesic lead optimization.

• A role of the transient receptor potential domain of vanilloid receptor I in channel gating.

  Authors: Nuria García-Sanz, Pierluigi Valente, Ana Gomis, Asia Fernández-Carvajal, Gregorio Fernández-Ballester, Felix Viana, Carlos Belmonte, Antonio Ferrer-Montiel

  The Journal of neuroscience : the official journal of the Society for Neuroscience. 11/2007; 27(43):11641-50.

  Transient receptor potential vanilloid receptor subtype 1 (TRPV1) is an ionotropic receptor activated by temperature and chemical stimuli. The C-terminal region that is adjacent to the channel gate,Transient receptor potential vanilloid receptor subtype 1 (TRPV1) is an ionotropic receptor activated by temperature and chemical stimuli. The C-terminal region that is adjacent to the channel gate, recognized as the TRP domain, is a molecular determinant of receptor assembly. However, the role of this intracellular domain in channel function remains elusive. Here, we show that replacement of the TRP domain of TRPV1 with the cognate region of TRPV channels (TRPV2-TRPV6) did not affect receptor assembly and trafficking to the cell surface, although those receptors containing the TRP domain of the distantly related TRPV5 and TRPV6 did not display ion channel activity. Notably, functional chimeras exhibited an impaired sensitivity to the activating stimuli, consistent with a significant contribution of this protein domain to channel function. At variance with TRPV1, voltage-dependent gating of chimeric channels could not be detected in the absence of capsaicin and/or heat. Biophysical analysis of functional chimeras revealed that the TRP domain appears to act as a molecular determinant of the activation energy of channel gating. Together, these findings uncover a role of the TRP domain in intersubunit interactions near the channel gate that contribute to the coupling of stimulus sensing to channel opening.

• TRP Channel Trafficking

  Authors: Rosa Planells-Cases, Antonio Ferrer-Montiel

  01/2007;

  ISBN: 0849340489

• Design and characterization of a noncompetitive antagonist of the transient receptor potential vanilloid subunit 1 channel with in vivo analgesic and anti-inflammatory activity.

  Authors: Carolina García-Martínez, Asia Fernández-Carvajal, Belen Valenzuela, Ana Gomis, Wim Van Den Nest, Stefano Ferroni, Cristina Carreño, Carlos Belmonte, Antonio Ferrer-Montiel

  The journal of pain : official journal of the American Pain Society. 11/2006; 7(10):735-46.

  Vanilloid receptor subunit 1 (TRPV1) is an integrator of physical and chemical stimuli in the peripheral nervous system. This receptor plays a key role in the pathophysiology of inflammatory pain.Vanilloid receptor subunit 1 (TRPV1) is an integrator of physical and chemical stimuli in the peripheral nervous system. This receptor plays a key role in the pathophysiology of inflammatory pain. Thus, the identification of receptor antagonists with analgesic and anti-inflammatory activity in vivo is an important goal of current neuropharmacology. Here, we report that [L-arginyl]-[N-[2,4-dichlorophenethyl]glycyl]-N-(2,4-dichlorophenethyl) glycinamide (H-Arg-15-15C) is a channel blocker that abrogates capsaicin and pH-evoked TRPV1 channel activity with submicromolar activity. Compound H-Arg-15-15C preferentially inhibits TRPV1, showing marginal block of other neuronal receptors. Compound H-Arg-15-15C acts as a noncompetitive capsaicin antagonist with modest voltage-dependent blockade activity. The compound inhibited capsaicin-evoked nerve activity in afferent fibers without affecting mechanically activated activity. Notably, administration of compound H-Arg-15-15C prevented the irritant activity of a local administration of capsaicin and formalin and reversed the thermal hyperalgesia evoked by injection of complete Freund's adjuvant. Furthermore, it attenuated carrageenan-induced paw inflammation. Compound H-Arg-15-15C specifically decreased inflammatory conditions without affecting normal nociception. Taken together, these findings demonstrate that compound H-Arg-15-15C is a channel blocker of TRPV1 with analgesic and anti-inflammatory activity in vivo at clinically useful doses and substantiate the tenet that TRPV1 plays an important role in the etiology of chronic inflammatory pain. PERSPECTIVE: This study reports the design of a potent TRPV1 noncompetitive antagonist that exhibits anti-inflammatory and analgesic activity in preclinical models of acute and chronic pain. This compound is a lead for analgesic drug development.

• Old molecules for new receptors: Trp(Nps) dipeptide derivatives as vanilloid TRPV1 channel blockers.

  Authors: M Angeles Bonache, Carolina García-Martínez, Laura García de Diego, Cristina Carreño, M Jesús Pérez de Vega, M Teresa García-López, Antonio Ferrer-Montiel, Rosario González-Muñiz

  ChemMedChem. 05/2006; 1(4):429-38.

  The transient receptor potential vanilloid member 1 (TRPV1), an integrator of multiple pain-producing stimuli, is regarded nowadays as an important biological target for the discovery of novelThe transient receptor potential vanilloid member 1 (TRPV1), an integrator of multiple pain-producing stimuli, is regarded nowadays as an important biological target for the discovery of novel analgesics. Here, we describe the first experimental evidence for the behavior of an old family of analgesic dipeptides, namely Xaa-Trp(Nps) and Trp(Nps)-Xaa (Xaa=Lys, Arg) derivatives, as potent TRPV1 channel blockers. We also report the synthesis and biological investigation of a series of new conformationally restricted Trp(Nps)-dipeptide derivatives with improved TRPV1/NMDA selectivity. Compound 15 b, which incorporates an N-terminal 2S-azetidine-derived Arg residue, was the most selective compound in this series. Collectively, a new family of TRPV1 channel blockers emerged from our results, although further modifications are required to fine-tune the potency/selectivity/toxicity balance.

• Characterization of a neural-specific splicing form of the human neuregulin 3 gene involved in oligodendrocyte survival.

  Authors: Christelle Carteron, Antonio Ferrer-Montiel, Hugo Cabedo

  Journal of cell science. 04/2006; 119(Pt 5):898-909.

  Neuregulins are a family of genes involved in key aspects of neural biology. Neuregulins 1, 2 and 3 (NRG1, NRG2 and NRG3) are expressed in the mammalian nervous system. It is well established thatNeuregulins are a family of genes involved in key aspects of neural biology. Neuregulins 1, 2 and 3 (NRG1, NRG2 and NRG3) are expressed in the mammalian nervous system. It is well established that NRG1, with fifteen different splicing forms, is central for brain development and function. However, the biological relevance of NRG2 and NRG3 remains elusive. Here, we report the identification of a new isoform of NRG3 that is specifically expressed in the human embryonic central nervous system. Sequence alignment with the human genome suggests that this transcript is produced by alternative promoter usage. The encoded polypeptide is a type-I-glycosylated plasma membrane protein, which is shed into the extracellular space where it activates erbB4, a pivotal receptor for brain development. In addition, we show that the protein has a signal sequence that is cleaved after membrane insertion. Proteasome inhibition with Lactacystin enhances the expression of the protein, whereas impairment of ubiquitylation in the conditional mutant cell line ts20 protects the protein from degradation. These observations imply that the ubiquitin/proteasome pathway regulates biogenesis of the protein. We also show that recombinant neuregulin 3 acts as an oligodendrocyte survival factor by activating the phosphoinositide 3-kinase signalling pathway. Therefore, we report a new post-translationally regulated isoform of neuregulin 3 expressed in the developing human central nervous system with a role in oligodendrocyte survival.

• Physiology and pharmacology of the vanilloid receptor.

  Authors: Angel Messeguer, Rosa Planells-Cases, Antonio Ferrer-Montiel

  Current neuropharmacology. 02/2006; 4(1):1-15.

  The identification and cloning of the vanilloid receptor 1 (TRPV1) represented a significant step for the understanding of the molecular mechanisms underlying the transduction of noxious chemical andThe identification and cloning of the vanilloid receptor 1 (TRPV1) represented a significant step for the understanding of the molecular mechanisms underlying the transduction of noxious chemical and thermal stimuli by peripheral nociceptors. TRPV1 is a non-selective cation channel gated by noxious heat, vanilloids and extracellular protons. TRPV1 channel activity is remarkably potentiated by pro-inflammatory agents, a phenomenon that is thought to underlie the peripheral sensitisation of nociceptors that leads to thermal hyperalgesia. Cumulative evidence is building a strong case for the involvement of this receptor in the etiology of both peripheral and visceral inflammatory pain, such as inflammatory bowel disease, bladder inflammation and cancer pain. The validation of TRPV1 receptor as a key therapeutic target for pain management has thrust intensive drug discovery programs aimed at developing orally active antagonists of the receptor protein. Nonetheless, the real challenge of these drug discovery platforms is to develop antagonists that preserve the physiological activity of TRPV1 receptors while correcting over-active channels. This is a condition to ensure normal pro-prioceptive and nociceptive responses that represent a safety mechanism to prevent tissue injury. Recent and exciting advances in the function, dysfunction and modulation of this receptor will be the focus of this review.

• Pharmacological intervention at ionotropic glutamate receptor complexes.

  Authors: Rosa Planells-Cases, Juan Lerma, Antonio Ferrer-Montiel

  Current pharmaceutical design. 02/2006; 12(28):3583-96.

  L-glutamate is considered the main excitatory neurotransmitter in the mammalian brain. Paradoxically, L-glutamate is also the most important excitotoxin pivotally involved in the aetiology of severalL-glutamate is considered the main excitatory neurotransmitter in the mammalian brain. Paradoxically, L-glutamate is also the most important excitotoxin pivotally involved in the aetiology of several neurodegenerative diseases such as stroke, Alzheimer, Parkinson, amyotropic lateral sclerosis, Huntington and neuropathic pain. L-glutamate signalling is transduced both presynaptically and postsynaptically by metabotropic and ionotropic receptors. Three types of glutamate-gated channels integrate the synaptic signal, namely AMPA, kainate and NMDA receptors. Sustained activation of these receptors, and especially of the NMDA receptor, is a casuistic phenomenon that leads to the neuronal death underlying neurodegeneration. Thus, pharmacological intervention at these neuronal receptors and their synaptic protein complexes is a valuable therapeutic strategy. The approval of memantine, a safe, well-tolerated uncompetitive NMDA antagonist for the treatment of moderate to severe Alzheimer dementia validates ionotropic glutamate receptors as key therapeutic targets of neurodegenerative diseases in humans. As a consequence, an enormous effort is being carried out to identify and develop safe and potent antagonists for the clinics. In this review, we will describe progress in this important arena of human health.

• Functional aspects and mechanisms of TRPV1 involvement in neurogenic inflammation that leads to thermal hyperalgesia.

  Authors: Rosa Planells-Cases, Nuria Garcìa-Sanz, Cruz Morenilla-Palao, Antonio Ferrer-Montiel

  Pflügers Archiv : European journal of physiology. 11/2005; 451(1):151-9.

  Neurogenic inflammation is produced by overstimulation of peripheral nociceptor terminals by injury or inflammation of tissues. Excessive activity of sensory neurons produces vasodilation, plasmaNeurogenic inflammation is produced by overstimulation of peripheral nociceptor terminals by injury or inflammation of tissues. Excessive activity of sensory neurons produces vasodilation, plasma extravasation and hypersensitivity. Mechanistically, neurogenic inflammation is due to the release of substances from primary sensory nerve terminals that act directly or indirectly at the peripheral terminals, either activating or sensitizing nociceptors, endothelial cells and immunocytes. Notably, small-diameter sensory neurons that are sensitive to capsaicin play a key role in the generation of neurogenic inflammation. The cloning of the vanilloid receptor 1 (TRPV1) has been a breakthrough that has propelled our understanding of the molecular mechanisms involved in neurogenic inflammation. TRPV1 pivotally contributes to the integration of various stimuli and modulates nociceptor excitability, thus making it a true gateway for pain transduction. In addition, TRPV1 is the endpoint target of intracellular signalling pathways triggered by inflammatory mediators. Phosphorylation-induced potentiation of TRPV1 channel activity, along with an incremented TRPV1 surface expression are major events underlying the nociceptor activation and sensitization that leads to thermal hyperalgesia. The important contribution of TRPV1 receptor to the onset and maintenance of neurogenic inflammation has validated it as a therapeutic target for inflammatory pain management. As a result, the development of specific TRPV1 antagonists is a central focus of current drug discovery programs.