The vanilloid receptor 1 (VR1 or TRPV1) is a membrane-bound, nonselective cation channel expressed by peripheral sensory neurons. TRPV1 antagonists produce antihyperalgesic effects in animal models of inflammatory and neuropathic pain. Here, we describe the in vitro and in vivo pharmacology of a novel TRPV1 antagonist, AMG 9810,AMG 9810 is a competitive antagonist of capsaicin activation (IC 50 value for human TRPV1, 24.5 Ϯ 15.7 nM; rat TRPV1, 85.6 Ϯ 39.4 nM) and blocks all known modes of TRPV1 activation, including protons (IC 50 value for rat TRPV1, 294 Ϯ 192 nM; human TRPV1, 92.7 Ϯ 72.8 nM), heat (IC 50 value for rat TRPV1, 21 Ϯ 17 nM; human TRPV1, 15.8 Ϯ 10.8 nM), and endogenous ligands, such as anandamide, N-arachidonyl dopamine, and oleoyldopamine. AMG 9810 blocks capsaicin-evoked depolarization and calcitonin gene-related peptide release in cultures of rat dorsal root ganglion primary neurons. Screening of AMG 9810 against a panel of G protein-coupled receptors and ion channels indicated selectivity toward TRPV1. In vivo, AMG 9810 is effective at preventing capsaicin-induced eye wiping in a dose-dependent manner, and it reverses thermal and mechanical hyperalgesia in a model of inflammatory pain induced by intraplantar injection of complete Freund's adjuvant. At effective doses, AMG 9810 did not show any significant effects on motor function, as measured by open field locomotor activity and motor coordination tests. AMG 9810 is the first cinnamide TRPV1 antagonist reported to block capsaicin-induced eye wiping behavior and reverse hyperalgesia in an animal model of inflammatory pain.Activation of peripheral nociceptors in humans by capsaicin results in burning pain (Park et al., 1995). Capsaicin, and its ultrapotent analog resiniferatoxin, aided the identification and characterization of the vanilloid receptor 1 (aka VR1 and TRPV1). TRPV1 is a nonselective cation channel with high permeability to calcium (Caterina et al., 1997) and belongs to a superfamily of ion channels known as the transient receptor potential channels or TRPs (Clapham et al., 2001). In addition to activation by exogenous agonists such as capsaicin and resiniferatoxin, TRPV1 can be activated by physical stimuli, such as heat (Ͼ42°C) and protons (pH 5). Based on their structural similarity to capsaicin, several endogenous ligands have been proposed that include anandamide (AEA), 12-hydroperoxy-5,8,10,14-eicosatetraenoic acid,N-arachidonyl dopamine (NADA), N-oleoyldopamine (OLDA), and products of lipoxygenases (Hwang et al., 2000;Olah et al., 2001;Huang et al., 2002;Chu et al., 2003). TRPV1 is up-regulated during inflammation (Ji et al., 2002), and channel activity is modulated by the action of inflammaArticle, publication date, and citation information can be found at http://jpet.aspetjournals.org.doi :

Low-frequency coding DNA sequence variants in the proprotein convertase subtilisin/kexin type 9 gene (PCSK9) lower plasma low-density lipoprotein cholesterol (LDL-C), protect against risk of coronary heart disease (CHD), and have prompted the development of a new class of therapeutics. It is uncertain whether the PCSK9 example represents a paradigm or an isolated exception. We used the "Exome Array" to genotype >200,000 low-frequency and rare coding sequence variants across the genome in 56,538 individuals (42,208 European ancestry [EA] and 14,330 African ancestry [AA]) and tested these variants for association with LDL-C, high-density lipoprotein cholesterol (HDL-C), and triglycerides. Although we did not identify new genes associated with LDL-C, we did identify four low-frequency (frequencies between 0.1% and 2%) variants (ANGPTL8 rs145464906 [c.361C>T; p.Gln121*], PAFAH1B2 rs186808413 [c.482C>T; p.Ser161Leu], COL18A1 rs114139997 [c.331G>A; p.Gly111Arg], and PCSK7 rs142953140 [c.1511G>A; p.Arg504His]) with large effects on HDL-C and/or triglycerides. None of these four variants was associated with risk for CHD, suggesting that examples of low-frequency coding variants with robust effects on both lipids and CHD will be limited.

We and others recently reported tumor necrosis factor (TNF) and apoptosis ligand-related leukocyte-expressed ligand 1 (TALL-1) as a novel member of the TNF ligand family that is functionally involved in B cell proliferation. Transgenic mice overexpressing TALL-1 have severe B cell hyperplasia and lupus-like autoimmune disease. Here, we describe expression cloning of a cell surface receptor for TALL-1 from a human Burkitt's lymphoma RAJI cell library. The cloned receptor is identical to the previously reported TNF receptor (TNFR) homologue transmembrane activator and calcium modulator and cyclophilin ligand (CAML) interactor (TACI). Murine TACI was subsequently isolated from the mouse B lymphoma A20 cells. Human and murine TACI share 54% identity overall. Human TACI exhibits high binding affinities to both human and murine TALL-1. Soluble TACI extracellular domain protein specifically blocks TALL-1-mediated B cell proliferation without affecting CD40-or lipopolysaccharide-mediated B cell proliferation in vitro. In addition, when injected into mice, soluble TACI inhibits antibody production to both T cell-dependent and -independent antigens. By yeast two-hybrid screening of a B cell library with TACI intracellular domain, we identified that, like many other TNFR family members, TACI intracellular domain interacts with TNFR-associated factor (TRAF)2, 5, and 6. Correspondingly, TACI activation in a B cell line results in nuclear factor B and c-Jun NH 2 -terminal kinase activation. The identification and characterization of the receptor for TALL-1 provides useful information for the development of a treatment for B cellmediated autoimmune diseases such as systemic lupus erythematosus.

Antagonists of the vanilloid receptor TRPV1 (transient receptor potential vanilloid type 1) have been reported to produce antihyperalgesic effects in animal models of pain. These antagonists, however, also caused concomitant hyperthermia in rodents, dogs, monkeys, and humans. Antagonist-induced hyperthermia was not observed in TRPV1 knockout mice, suggesting that the hyperthermic effect is exclusively mediated through TRPV1. Since antagonist-induced hyperthermia is considered a hurdle for developing TRPV1 antagonists as therapeutics, we investigated the possibility of eliminating hyperthermia while maintaining antihyperalgesia. Here, we report four potent and selective TRPV1 modulators with unique in vitro pharmacology profiles (profiles A through D) and their respective effects on body temperature. We found that profile C modulator, (R,E)-N-(2-hydroxy-2,3-dihydro-1H-inden-4-yl)-3-(2-(piperidin-1-yl)-4-(trifluoromethyl)phenyl)acrylamide (AMG8562), blocks capsaicin activation of TRPV1, does not affect heat activation of TRPV1, potentiates pH 5 activation of TRPV1 in vitro, and does not cause hyperthermia in vivo in rats. We further profiled AMG8562 in an on-target (agonist) challenge model, rodent pain models, and tested for its side effects. We show that AMG8562 significantly blocks capsaicin-induced flinching behavior, produces statistically significant efficacy in complete Freund's adjuvant-and skin incision-induced thermal hyperalgesia, and acetic acid-induced writhing models, with no profound effects on locomotor activity. Based on the data shown here, we conclude that it is feasible to modulate TRPV1 in a manner that does not cause hyperthermia while maintaining efficacy in rodent pain models.The vanilloid receptor TRPV1 emerged as a therapeutic target for pain based on the fact that 1) TRPV1 agonists cause pain (Szallasi and Blumberg, 1999;Jones et al., 2004), 2) TRPV1 expression is up-regulated during painful conditions (Ji et al., 2002;Matthews et al., 2004), 3) TRPV1 knockout mice display attenuated pain behaviors (Caterina et al., 2000;Davis et al., 2000;Keeble et al., 2005), and 4) TRPV1 antagonists reverse AMG 517,

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