G protein-coupled receptors in major psychiatric disorders

Laboratory of Molecular Pathophysiology, Mood and Anxiety Disorders Program, National Institute of Mental Health, NIH, HHS, Bethesda, MD 20892, USA.
Biochimica et Biophysica Acta (Impact Factor: 4.66). 05/2007; 1768(4):976-93. DOI: 10.1016/j.bbamem.2006.09.025
Source: PubMed


Although the molecular mechanisms underlying psychiatric illnesses such as depression, bipolar disorder and schizophrenia remain incompletely understood, there is increasing clinical, pharmacologic, and genetic evidence that G protein-coupled receptors (GPCRs) play critical roles in these disorders and their treatments. This perspectives paper reviews and synthesizes the available data. Dysfunction of multiple neurotransmitter and neuropeptide GPCRs in frontal cortex and limbic-related regions, such as the hippocampus, hypothalamus and brainstem, likely underlies the complex clinical picture that includes cognitive, perceptual, affective and motoric symptoms. The future development of novel agents targeting GPCR signaling cascades remains an exciting prospect for patients refractory to existing therapeutics.

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Available from: Alberico L Catapano
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    • "In summary, in the current study we have characterized the role of the PDZ domain–containing protein SAP97 as a novel regulator of 5HT 2A R trafficking and signaling and confirm a receptor-independent role for SAP97 in regulating ERK1/2 signaling. PDZ domain–containing proteins of the PSD-95/ SAP97 family have an established link to the regulation and treatment of mood disorders and psychiatric disease that may implicate 5HT 2A R signaling (Gray and Roth, 2001; Roth and Xia, 2004; Catapano and Manji, 2007). The efficacy of second-generation atypical antipsychotics appears to be dependent on their ability to downregulate 5HT 2A R-mediated signaling , while upregulating metabotropic–glutamate receptor 2 (mGluR2) signaling (Fribourg et al., 2011). "
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    ABSTRACT: Serotonin (5-HT) interacts with a wide variety of 5-HT receptors (5-HTR) of which 5-HT2AR plays an important target for antidepressant and atypical antipsychotic drugs. The carboxyl-terminal tail of 5-HT2AR encodes a motif that mediates interactions with PSD-95/Discs Large/Zona Occludens 1 (PDZ) domain containing proteins. In the present study, we found that 5-HT2AR interacts with synapse-associated protein 97 (SAP97; also known as DLG1) by co-immunoprecipitation in human embryonic 293 (HEK 293) cells and cortical brain lysates. We find that 5-HT2AR expression results in the recruitment of SAP97 from the cytosol to the plasma membrane and that this recruitment is dependent upon an intact 5-HT2AR PDZ binding motif. We also show that 5-HT2AR interacts with SAP97 using bioluminescence energy transfer and that overexpression of SAP97 retards 5-HT2AR endocytosis, while single hair pin RNA knockdown facilitates 5-HT2AR internalization. The knockdown of SAP97 in HEK 293 cells results in a reduction in the maximum efficacy for 5-HT2AR-stimulated inositol phosphate formation and that the deletion of the 5-HT2AR PDZ motif also impairs 5-HT2AR signaling. Similar to what has been observed for the corticotropin releasing factor receptor 1 (CRFR1), SAP97 expression is essential for 5-HT2AR-stimulated ERK1/2 phosphorylation by a PDZ interaction-independent mechanism. Moreover, we find that SAP97 is not responsible for CRFR1-mediated sensitization of 5-HT2AR signaling. Taken together, our studies show that SAP97 plays a conserved role in regulating 5-HT2AR endocytosis and ERK1/2 signaling, but plays a novel role in regulating 5-HT2AR G protein coupling.
    Full-text · Article · Jul 2014 · Molecular pharmacology
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    • "More important, the large and important family of G protein coupled receptors (GPCRs) is implicated in some psychiatric disorders. Indeed, in addition to the alteration of the functions of multiple GPCRs in the depressive state, antidepressant treatment influences GPCR activity (Catapano and Manji, 2007; Dunlop and Nemeroff, 2007) which indicates, due to the pharmacological importance GPCRs have among the modern pharmacotherapies, promising therapeutic possibilities. "
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    ABSTRACT: Psychiatric disorders are often considered as simple imbalances between a limited number of cerebral neurotransmitters. In fact, it is more complicated than this “simple approach” and each psychiatric disorder constitutes network dysfunction within which several agents and factors are implicated. Thus, the therapeutical perspectives and implications are as vast and as numerous as the diversity of those network dysfunctions. Furthermore, the description of factors influencing diseases prognoses and treatment efficacy indicates new elements to consider both in therapies and drug researches.
    Full-text · Article · Apr 2014 · Saudi Pharmaceutical Journal
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    • "Of the GPCR recognized as 5HTR, the 5HT1aR (a relative of BAR) is one of the most highly studied [23] [24] [25], and it has been associated with physiological and pathological processes as diverse as thermoregulation, cognitive flexibility, and control of mood [26] [27] [28] [29] [30] [31] [32] [33]. Depression, underlying anxiety disorders, and related psychopathologies are a particular theme [34] [35] [36] [37] [38] [39]. Multiple strategies have been used to dissect the complex pathways underscoring these physiological and pathological processes [40] [41] [42] [43] [44] [45] [46] [47]. "
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