Publications (17)0 Total impact
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Xochella Chan,
Brock Brown,
Michael Hedrick,
Justin Rascon,
José Luis Millán,
Eduard Sergienko,
Greg Roth,
Santhi Reddy, Shakeela Dad,
Thomas DY Chung,
Nicholas Cosford,
Derek Stonich,
Ying Su
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ABSTRACT: Novel and specific activators of the pyrophosphatase activity of tissue non-specific alkaline phosphatase (TNAP) may serve as chemical research tools to delineate the biological function of TNAP, as well as provide leads for drugs to treat hypophosphatasia and osteoporosis. In addition, such tools may serve as useful molecular probes to dissect the transition from in vitro potency to efficacy in ex vivo models. TNAP catalyzes a dephosphorylation reaction that proceeds through the formation of a stable covalent intermediate. As with other alkaline phosphatases, the hydrolysis of the phosphoserine intermediate is the rate-limiting step of the overall TNAP reaction and, consequently, in the steady state, the majority of the enzyme exists in the covalent intermediate form. This project has identified ML088 (CID-704205) and ML087 (CID-25199559) as biochemical activators of TNAP. These probes are expected to exhibit their effects on TNAP catalytic activity through reversible equilibrium binding. Furthermore, these findings provide promise that administration of either recombinant TNAP itself, or of these chemical probes as pharmacological activators of TNAP's pyrophosphatase activity, may serve as novel therapeutics drugs for the treatment of hypophosphatasia and osteoporosis.
01/2010;
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Kate Welsh,
Hongbin Yuan,
Derek Stonich,
Ying Su,
Xocella Garcia,
Michael Cuddy,
Richard Houghten,
Eduard Sergienko,
John C Reed,
Robert Ardecky,
Santhi Reddy Ganji,
Marcos Lopez, Shakeela Dad,
Thomas DY Chung,
Nicholas Cosford
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ABSTRACT: Multiple member of Inhibitor of Apoptosis Proteins (IAPs) family are simultaneously overexpressed in many cancers. As a result, antisense or RNA interference (RNAi) methods for assessing function of these proteins are lacking. Selective probing the binding of small molecule compounds against either the BIR2 or BIR3 SMAC (second mitochondria-derived activator of caspase)-binding sites on a number of IAPs, (e.g. XIAP, cIAP1, cIAP2) may generate useful tools for elucidating their role in cancer biology. The goals of this project were: (1) to generate small molecule compounds that mimic the effects of SMAC peptides to inhibit the function of IAPs; (2) to find non-peptidyl small molecule chemical inhibitors that have advantages over SMAC peptides, in terms of cell permeability, stability, in vivo pharmacology and potency, ideally 1 uM or better; and (3) to identify compounds that inhibit the BIR2 domain of XIAP, either selectively or in addition to inhibiting the BIR3 domain. The selective probe ML101 (CID-25241665) mimics the binding of a single AVPI binding motif in demonstrating potent binding affinity and selectivity for BIR1/2 domain of XIAP.
01/2010;
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Eduard Sergienko,
Xochella Garcia,
Brock Brown,
Justin Rascon,
Sonoko Narisawa,
Ana Maria Simao,
José Luis Millán,
Derek Stonich,
Ying Su,
Pasha Khan,
Greg Roth,
Layton Smith, Shakeela Dad,
Thomas DY Chung,
Nicholas DP Cosford
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ABSTRACT: Placental alkaline phosphatase (PLAP) is highly expressed in primate placental tissue. Its biological function and relevance are still unknown, but PLAP-like enzymes are detected in serum of patients with primary testicular tumors, in particular seminoma and other cancers. Consequently, the identification of PLAP-specific inhibitors with selectivity over tissue non-specific alkaline phosphatase (TNAP) and intestinal alkaline phosphatase (IAP) may provide the necessary tools to characterize its biological role. Currently, inhibitors of PLAP lack either potency or selectivity. The small molecule probe ML085 (CID-25067483) is a biochemical inhibitor of PLAP, and will be useful to elucidate the key biological functions and natural substrates of human PLAP.
01/2010;
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Michael Hedrick,
Brock Brown,
Justin Rascon,
Eduard Sergienko,
Vandana Sharma,
Bobby Ng,
Mie Ichikawa,
Hudson Freeze,
Derek Stonich,
Ying Su, Shakeela Dad,
Thomas DY Chung,
Russell Dahl,
Nick Cosford
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ABSTRACT: Type Ia Congenital Disorders of Glycosylation (CDG-Ia) is the most common form of the Congenital Disorders of Glycosylation. This autosomal recessive disorder impairs the synthesis of N-linked oligosaccharide chains and is caused by defects in the PMM2 gene. PMM2 encodes phosphomannomutase 2, which is responsible for the conversion of mannose-6-P [Man-6-P] to Man-1-P. Currently, there is no treatment for CDG-Ia patients. The current project aimed to identify novel non-competitive inhibitors of phosphomannose isomerase, PMI. as potential therapeutic treatments for these patients. The developed probe ML096 (CID-25199533) inhibits human PMI and may inhibit other PMI orthologs due to the highly conserved nature of the enzyme. The probe is membrane permeable and, as a result can also be used to inhibit PMI in living cells. Thus, the probe may serve as a therapeutic treatment for CDG-Ia patients by blocking the catabolism of Man-6-P in cells, thereby redirecting it towards protein glycosylation using this residual PMM2 activity.
01/2010;
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Dereck Stonich,
Ying Su, Shakeela Dad,
Santhi Reddy,
Yalda Mostofi,
Dahl Russell,
Thomas DY Chung,
Nicholas Michael Hedrick,
Justin Rascon,
Xochella Garcia,
Eduard Sergienko,
José Luis Millán,
Derek Stonich,
Nicholas Cosford
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ABSTRACT: Defective bone mineralization (osteomalacia) occurs in tissue non-specific alkaline phosphatase (TNAP) deficiency (hypophosphatasia). TNAP functions to maintain normal bone mineralization via hydrolysis of inorganic pyrophosphate (PPi), a bone mineralization inhibitor. This study sought to examine the role of PHOSPHO1, a soluble phosphatase that has specificity for phosphoethanolamine and phosphocholine, in increasing the inorganic phosphate (Pi)/inorganic pyrophosphate (PPi) ratio inside matrix vesicles (MVs) and, thus, controlling the first step of initiation of hydroxyapatite crystal deposition inside MVs. The identified molecular probe ML086 (CID-1674999) is a biochemical inhibitor of PHOSPHO1. PHOSPHO1-specific inhibitors may serve as novel tools to examine the functional role of this enzyme in skeletal mineralization and soft tissue ossification abnormalities, as well as to help elucidate its mechanism of action in diseases such as osteoarthritis, osteoporosis, and arterial calcification.
01/2010;
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Dmitri Rozanov,
Brock Brown,
Cheng-Tien Hung,
Eduard Sergienko,
Carlton Gasior,
Palak Shah,
Steve Vasile,
Ying Su,
Derek Stonich,
Patrick Maloney,
Greg Roth, Shakeela Dad,
Thomas DY Chung
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ABSTRACT: This study proposed to screen for small molecules compounds that selectively sensitize tumor cells to the extrinsic apoptosis pathway activated by Tumor necrosis factor-Related Apoptosis-Inducing Ligand (TRAIL) without affecting other cell death pathways and normal cells. These compounds represent potentially useful research tools for the elucidation of mechanisms of TRAIL-resistance, and might also serve as prototypic compounds for the development of a new generation of non-toxic anticancer drugs to restore sensitivity to endogenous pathways used by the immune system to eradicate tumors. The probe compound ML100 (CID-3380841) appears to selectively sensitize tumor cells in a TRAIL-dependent manner to the extrinsic apoptosis pathway activated by TRAIL, without effecting normal cells to this apoptosis-inducing cytokine.
01/2010;
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Michael P Hedrick,
Palak Gosalia,
Kevin Frankowski,
Shenghua Shi,
Thomas E Prisinzano,
Frank Schoenen,
Jeffrey Aubé,
Ying Su,
S Vasile,
Eduard Sergienko,
Wilson Gray,
Santosh Hariharan,
Partha Ghosh,
Loribelle Milan,
Susanne Heynen-Genel,
Thomas DY Chung, Shakeela Dad,
Marc Caron,
Laura M Bohn,
Lawrence S Barak
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ABSTRACT: The specific aim of this project is to identify subtype specific small molecule antagonists of the human kappa opioid (KOP) receptor that represent different chemical scaffolds than the many existing potent and selective literature antagonists. Such antagonists have been shown to prevent reinstatement of drug taking behavior in animal paradigms thought to model relapse, however all current antagonists are long-acting and lead to tolerance due to poor pharmacological clearance. On the basis of antagonist assay paradigms utilized in this project (G protein coupling, ERK activation and beta-arrestin recruitment), it is hypothesized that the mode of action of the identified probe, ML140 (CID-3342390), is through reversible binding at the KOR site occupied by opiates. Thus, in this paradigm, opioid agonist-stimulation is blocked by increasing doses of the antagonist probe. These novel scaffolds for KOP receptor antagonists are of interest because they may be short acting and rapidly cleared, and therefore find utility in the treatment of drug abuse, depression, and chronic pain without tolerance and habituation.
01/2010;
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Michael P Hedrick,
Palak Gosalia,
Kevin Frankowski,
Shenghua Shi,
Thomas E Prisinzano,
Frank Schoenen,
Jeffrey Aubé,
Ying Su,
S Vasile,
Eduard Sergienko,
Wilson Gray,
Santosh Hariharan,
Partha Ghosh,
Loribelle Milan,
Susanne Heynen-Genel,
Thomas DY Chung, Shakeela Dad,
Marc Caron,
Laura M Bohn,
Lawrence S Barak
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ABSTRACT: The κ opioid receptors (KOR) provide desirable substrates for targeted therapy and unraveling pathways responsible for mediating addictive behavior. Kappa opioid agonists offer a means to modulate the effects of stimulant drugs. However, there currently are no available approved agents or compounds for these purposes. Thus, the specific aim of this project was to identify subtype specific small molecule agonists of the human KOR. Such agonists might be useful in elucidating different signaling modalities for kappa receptors, but more importantly, they might also be partial agonists that will facilitate the discovery of new molecular scaffolds for kappa antagonists. In this report, we describe the discovery and optimization of two novel agonists for the KOR, the small molecular probes ML139 (CID-5236771) and ML138 (CID-44601470), each of which are greater than 100-fold selective over the mu-(µ) and delta (δ) opioid subtype receptors. Furthermore, these probes and their analogs represent novel chemical classes compared to current literature agonists, with potentially unique pharmacology that may serve as interesting tools to advance addiction research.
01/2010;
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Eduard Sergienko,
Ekatarina Bobkova,
Stefan Vasile,
Hongbin Yuan Ying Su,
Russell Dahl,
Li Yang,
Thomas DY Chung, Shakeela Dad,
Tomas Mustelin,
Wallace Liu,
David A Critton,
Rebecca Page,
Lutz Tautz
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ABSTRACT: Tyrosine phosphorylation plays a key role in signal transduction and the regulation of a broad set of physiological processes characteristic of multicellular organisms. Hematopoietic protein tyrosine phosphate (HePTP) is a tyrosine phosphatase expressed in hematopoietic cells with specificity for the dephosphorylation of Erk and p38 MAP kinases (MAPKs). It has been found that HePTP is often dysregulated in the preleukemic disorder myelodysplastic syndrome, as well as in acute myelogeneous leukemia. The identified probe ML119 (CID-1357397) selectively inhibits HePTP activity. Since this probe scaffold was discovered through its activity in the HePTP assays with small molecule substrates, it is proposed that this inhibition occurs through direct targeting of the HePTP active site. The probe inhibits through fast equilibrium as judged by the lack of apparent effect when pre-incubated with phosphatase proteins. Thus, small molecule inhibitors of HePTP would be useful as molecular probes for studying the mechanism of signal transduction and MAP kinase regulation. In addition, these probes may have therapeutic potential for the treatment of hematopoietic malignancies, such as acute myeloid leukemia, where HePTP has been reported to be overexpressed.
01/2010;
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Eduard Sergienko,
Ekaterina Bobkova,
Sharon Colayco,
Justin Rascon,
Xochella Chan,
Stefan Vasile,
Ying Su,
Russell Dahl,
Thomas DY Chung, Shakeela Dad,
Tomas Mustelin,
Wallace Liu,
David A Critton,
Rebecca Page,
Lutz Tautz
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ABSTRACT: Tyrosine phosphorylation is a key mechanism for signal transduction and the regulation of a broad set of physiological processes characteristic of multicellular organisms. Hematopoietic protein tyrosine phosphate (HePTP) is a tyrosine phosphatase expressed in hematopoietic cells with specificity for the dephosphorylation of Erk and p38 MAP kinases (MAPKs). It has been found that HePTP is often dysregulated in the preleukemic disorder myelodysplastic syndrome, as well as in acute myelogeneous leukemia. The identified probe ML120 (CID-4302116) selectively inhibits HePTP activity. Since this probe scaffold was discovered through its activity in the HePTP assays with small molecule substrates, it is proposed that this inhibition occurs through direct targeting of the HePTP active site. No time-dependent inhibition is observed as demonstrated by the linear progress curves of the HePTP phosphatase reaction in the presence of various concentrations of the ML120. Thus, small molecule inhibitors of HePTP would be useful as molecular probes for studying the mechanism of signal transduction and MAP kinase regulation. In addition, these probes may have therapeutic potential for the treatment of hematopoietic malignancies, such as acute myeloid leukemia, where HePTP has been reported to be overexpressed.
01/2010;
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DongHoon Chung,
Robert Ardecky,
Santhi Reddy Ganji,
Nicholas DP Cosford,
Colleen B Jonsson,
Blake P Moore,
Fuli Jia,
Clinton Maddox,
Sara N McKellip,
E Lucile White,
Subramaniam Ananthan,
Shuang Feng,
Lynn Rasmussen,
Ying Su,
Thomas DY Chung, Shakeela Dad,
Nichole A Tower,
Marintha Heil
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ABSTRACT: West Nile Virus (WNV) is a mosquito-borne pathogen that causes febrile illness and, occasionally, encephalitis when transmitted to humans. Infection can cause significant health problems such as West Nile fever and neuroinvasive disease. The goal of the assay was to identify and develop chemical probes that inhibit in vitro replication of WNV. An unbiased phenotypic whole virus cell-based assay was utilized to select chemical probes that inhibit WNV propagation without adversely affecting the host cell. The two probe candidates described in this report, ML143 (CID-2557019) and ML142 (CID-928277), provide two small molecules that demonstrate modest yet useful potency against the West Nile Virus, but with a robust margin of selectivity against cell cytotoxicity, providing potentially useful evaluation tools for small animal toxicity and efficacy studies.
01/2010;
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Gavin Magnuson,
Pasha Khan,
Hongbin Yuan,
Brock Brown,
Daniela B Divlianska,
Derek Stonich,
Mahesh Peddibhotla,
Ying Su, Shakeela Dad,
Eduard Sergienko,
Thomas DY Chung,
Gregory P Roth,
Carina Wimer,
Paul Diaz,
Ricardo G Correa,
John C Reed
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ABSTRACT: The modulation of immune response activity is one of the major goals in the development of novel therapeutics for human immune or inflammatory diseases. The innate system resides at the intersection of the pathways of microbial recognition, inflammation, and cell death, thereby offering various therapeutic targets. In this context, NOD1 and NOD2 are of particular interest, since they recognize distinct structures derived from bacterial peptidoglycans and directly activate the NF-κB pathway, which controls the production of proinflammatory molecules. Mutations in the NOD1 and NOD2 genes are associated with a number of human inflammatory disorders, including Crohn's disease (CD), Blau syndrome, early-onset sarcoidosis, and atopic diseases, which characteristically cause constitutive NF-κB activation. Thus, small molecule inhibitors of NOD1 would provide powerful research tools for elucidating the roles of these proteins in modulating immune response in primary cultured cells from humans and in animal models. This probe report describes ML146 (CID-5310346), a second specific inhibitor of the NOD1-mediated activation of NF-κB of a new chemical class (purine-2,6-dione) compared to the previously submitted NOD1 specific inhibitor, ML130 (CID-1088438). While this probe is not as potent or selective as the first probe, CID-1088438, it does meet probe criteria and represents a second bona fide scaffold for a NOD1 selective probe.
01/2010;
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Susanne Heynen-Genel,
Russell Dahl,
Shenghua Shi,
Michelle Sauer,
Santosh Hariharan,
Eduard Sergienko, Shakeela Dad,
Thomas DY Chung,
Derek Stonich,
Ying Su,
Marc Caron,
Pingwei Zhao,
Mary E Abood,
Lawrence S Barak
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ABSTRACT: Although many known receptors that regulate addiction have been pharmacologically and biochemically well characterized, some orphan receptors with homology to known receptors of abuse (i.e. GPR35) remain uncharacterized. GPR35 is a G-protein coupled receptor, first identified in 1998 after a screen of a human genomic library. More recent RT-PCR studies have now confirmed the presence of GPR35 in dorsal root ganglion, the cerebellum and brain, as well as GPR35b, which was cloned from a human whole brain cDNA library. Thus, GPR35 regulation appears to have profound physiological and pathophysiological implications. In line with the specific aim of this project, the identified probes ML145 (CID-2286812) and ML144 (CID-1542103) represent selective antagonists for GPR35, but not for the related GPR55 orphan receptor, supporting the hypothesis that they do not produce non-specific interference with signaling directly at or downstream of the β-arrestin signaling pathway. These probes will serve as novel tools to delineate the biochemistry of GPR35 as potential therapeutics to selectively target pathways underlying pain and to enhance our understanding of the molecular basis of addiction.
01/2010;
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Susanne Heynen-Genel,
Russell Dahl,
Shenghua Shi,
Loribelle Milan,
Santosh Hariharan,
Yalda Bravo,
Eduard Sergienko,
Michael Hedrick, Shakeela Dad,
Derek Stonich,
Ying Su,
Michael Vicchiarelli,
Arianna Mangravita-Novo,
Layton H Smith,
Thomas DY Chung,
Haleli Sharir,
Lawrence S Barak,
Mary E Abood
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ABSTRACT: The orphan G protein coupled receptor, GPR55, has gained notoriety because of its putative identification as a cannabinoid receptor subtype. The significance of this assignment should not be underestimated given the importance of cannabinoids to drug abuse and the potential utility of cannabinoid ligands in treating behavioral disorders leading to conditions such as obesity. The validity of assigning GPR55 to the cannabinoid family is problematic based upon the discovery that endogenous compounds not related to cannabinoid receptor ligands also bind and signal through GPR55. As a consequence, it is important to identify GPR55-selective ligands that can precisely define GPR55’s role in regulating addictive behaviors. Lysophosphatidylinositol (LPI; 1.2 μM) is representative of the recently identified endogenous GPR55 ligands and the CB1 inverse agonist/antagonists SR141716A (3.9 μM) and AM251 (9.6 μM), that are also GPR55 agonists, are representative of the cannabinoid receptor ligands that were screened against GPR55 when selectivity was not a consideration. The availability of high potency selective GPR55 agonists will therefore facilitate the study of this receptor’s signaling. We have identified 3 potent and selective agonists for GPR55, which represent 3 different chemical scaffolds: 1) a morpholinosulfonylphenylamide, ML186 (CID15945391) with 305 nM potency for GPR55 and >100-fold selectivity against GPR35, CB1 and CB2 (as agonist and antagonists); 2) a tricyclic triazoloquinoline, ML185 (CID1374043) with 658 nM potency for GPR55 and >48-fold selectivity against GPR35, CB1 and CB2 (as agonists and antagonists); and 3) a piperazine, ML184 (2440433) with 263 nM potency for GPR55 and >120-fold, 83-fold, and 57-fold selectivity against GPR35, CB1 and CB2 as antagonists, and >120-fold selective against all 3 counter receptors as agonists. All three probes also are active in activating the downstream responses of ERK phosphorylation and PKC β II translocation.
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Susanne Heynen-Genel,
Russell Dahl,
Shenghua Shi,
Loribelle Milan,
Santosh Hariharan,
Eduard Sergienko,
Michael Hedrick, Shakeela Dad,
Derek Stonich,
Ying Su,
Michael Vicchiarelli,
Arianna Mangravita-Novo,
Layton H Smith,
Thomas DY Chung,
Haleli Sharir,
Marc G Caron,
Lawrence S Barak,
Mary E Abood
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ABSTRACT: The orphan G protein coupled receptor, GPR55, has gained notoriety because of its putative identification as a cannabinoid receptor subtype. The significance of this assignment should not be underestimated given the importance of cannabinoids to drug abuse and the potential utility of cannabinoid ligands in treating behavioral disorders leading to conditions such as obesity. The validity of assigning GPR55 to the cannabinoid family is problematic based upon the discovery that endogenous compounds not related to cannabinoid receptor ligands also bind and signal through GPR55. As a consequence, it is important to identify GPR55-selective ligands that can precisely define GPR55’s role in regulating addictive behaviors. Cannabidiol has been reported as a GPR55 antagonist in the literature to GPR55 activation by O1062, but this could not be confirmed our laboratory (Dr. Abood & Dr. Barak). There are no other known small molecule antagonists of GPR55 reported to date, only the CB1 inverse agonist/antagonists SR141716A (3.9 μM) and AM251 (9.6 μM). We have identified 3 potent and selective antagonists for GPR55, that represent 3 different chemical core scaffolds: 1) a quinoline aryl sulfonamide, ML193 (CID1261822) with a 221 nM potency for GPR55 and >145-fold, >27-fold and >145-fold antagonist selectivity against GPR35, CB1 and CB2, respectively and >145-fold agonist selectivity against all of these counter-receptors; 2) a thienopyrimidine, ML192 (CID1434953) with 1080 nM potency for GPR55 and >45-fold antagonist and agonist selectivity against GPR35, CB1 and CB2; and 3) a piperadinyloxadiazolone, ML191 (23612552) with 160 nM potency for GPR55 and >100-fold selectivity against GPR35, CB1 and CB2. All three probes also are active in inhibiting the downstream responses of ERK phosphorylation and PKC β II translocation.
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Marcos Lopez,
Kate Welsh,
Hongbin Yuan,
Derek Stonich,
Ying Su,
Xochella Garcia,
Michael Cuddy,
Richard Houghten,
Eduard Sergienko,
John C Reed,
Robert Ardecky,
Santhi Reddy,
Darren Finlay,
Kristiina Vuori, Shakeela Dad,
Thomas DY Chung,
Nicholas DP Cosford
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ABSTRACT: Various Inhibitors of Apoptosis Proteins (IAPs) are over-expressed in specific types of cancer, and some tumors over-express more than one member of this family of proteins simultaneously. Given that multiple IAPs are simultaneously over-expressed in many cancers, unfortunately antisense or RNA interference (RNAi) methods for assessing function of these proteins are presently often lacking. Therefore, probing the competition of small molecule compounds against either the BIR2 or BIR3 SMAC-binding sites on IAPs, such as XIAP, cIAP1, cIAP2 or other IAPs from human and other organisms will serve as useful tools for elucidating their roles in cancer biology. In this study, we investigated small molecule compounds that selectively mimic the effects of SMAC (second mitochondria-derived activator of caspase) in antagonizing IAPs by causing them to release Caspases. These non-peptidyl chemical inhibitors would have advantages over SMAC peptides, in terms of their greater cell permeability, stability, and in vivo pharmacology. As such, the probe identified in this report ML183 (CID 44176340) met the project’s goal of displaying potent binding affinity and selectivity for the BIR2 domain of XIAP. Moreover, in that tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) represents a potent inducer of apoptosis in a wide variety of tumor cells, another valuable finding of this project is that it also promotes cell survival against a challenge by rhTRAIL, an inducer of cell death.
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Susanne Heynen-Genel,
Russell Dahl,
Shenghua Shi,
Michelle Sauer,
Santosh Hariharan,
Eduard Sergienko, Shakeela Dad,
Thomas DY Chung,
Derek Stonich,
Ying Su,
Pingwei Zhao,
Marc G Caron,
Mary E Abood,
Lawrence S Barak
[show abstract]
[hide abstract]
ABSTRACT: Although many known receptors that regulate addiction have been pharmacologically and biochemically well characterized, some orphan receptors with homology to known receptors of abuse (i.e. GPR35) remain uncharacterized. GPR35 is a G-protein coupled receptor, first identified in 1998 after a screen of a human genomic library. More recent RT-PCR studies have now confirmed the presence of GPR35 in dorsal root ganglion, the cerebellum and brain, as well as GPR35b, which was cloned from a human whole brain cDNA library. Thus, GPR35 regulation appears to have profound physiological and pathophysiological implications. We have identified a 3rd antagonist, ML194 that represents a different chemical scaffold with potency (160 nM) and selectivity (>57-fold) for GPR35, but not for the related GPR55 orphan receptor, that is intermediate between the previously reported probes, ML145 (CID2286812) and ML144 (CID1542103). ML194 also does not seem to produce non-specific interference with signaling directly at or downstream of the β-arrestin signaling pathway, so it may serve as an additional tool to delineate the biochemistry of GPR35 as potential therapeutics to selectively target pathways underlying pain and to enhance our understanding of the molecular basis of addiction.
