ABSTRACT
Mental disorders (MD), such as anxiety, depression, and cognitive impairment, are very common during pregnancy and predispose to adverse pregnancy outcomes; however, the underlying mechanisms are still under intense investigation. Although the most common RNA modification in epigenetics, N6-methyladenosine (m6A) has been widely studied, its role in MD has not been investigated. Here, we observed that fat mass and obesity-associated protein (FTO) are downregulated in the hippocampus of pregnant rats with MD induced by fear stress and demonstrated that FTO participates in and regulates MD induced by fear stress. In addition, we identified four genes with anomalous modifications and expression (double aberrant genes) that were directly regulated by FTO, namely Angpt2, Fgf10, Rpl21, and Adcy7. Furthermore, we found that these genes might induce MD by regulating the PI3K/Akt and Rap1 signaling pathways. It appears that FTO-mediated m6A modification is a key regulatory mechanism in MD caused by fear stress during pregnancy.
Subject(s)
Alpha-Ketoglutarate-Dependent Dioxygenase FTO , Fear , Hippocampus , Mental Disorders , Stress, Psychological , Animals , Female , Pregnancy , Rats , Down-Regulation , Fibroblast Growth Factor 10 , Hippocampus/enzymology , Mental Disorders/enzymology , Phosphatidylinositol 3-Kinases , Stress, Psychological/enzymology , Alpha-Ketoglutarate-Dependent Dioxygenase FTO/metabolismABSTRACT
Small GTPases cycle between an inactive GDP-bound and an active GTP-bound state to control various cellular events, such as cell proliferation, cytoskeleton organization, and membrane trafficking. Clarifying the guanine nucleotide-bound states of small GTPases is vital for understanding the regulation of small GTPase functions and the subsequent cellular responses. Although several methods have been developed to analyze small GTPase activities, our knowledge of the activities for many small GTPases is limited, partly because of the lack of versatile methods to estimate small GTPase activity without unique probes and specialized equipment. In the present study, we developed a versatile and straightforward HPLC-based assay to analyze the activation status of small GTPases by directly quantifying the amounts of guanine nucleotides bound to them. This assay was validated by analyzing the RAS-subfamily GTPases, including HRAS, which showed that the ratios of GTP-bound forms were comparable with those obtained in previous studies. Furthermore, we applied this assay to the investigation of psychiatric disorder-associated mutations of RHEB (RHEB/P37L and RHEB/S68P), revealing that both mutations cause an increase in the ratio of the GTP-bound form in cells. Mechanistically, loss of sensitivity to TSC2 (a GTPase-activating protein for RHEB) for RHEB/P37L, as well as both decreased sensitivity to TSC2 and accelerated guanine-nucleotide exchange for RHEB/S68P, is involved in the increase of their GTP-bound forms, respectively. In summary, the HPLC-based assay developed in this study provides a valuable tool for analyzing small GTPases for which the activities and regulatory mechanisms are less well understood.
Subject(s)
Mental Disorders , Mutation, Missense , Ras Homolog Enriched in Brain Protein , Amino Acid Substitution , Chromatography, High Pressure Liquid , Enzyme Activation/genetics , HEK293 Cells , HeLa Cells , Humans , Mental Disorders/enzymology , Mental Disorders/genetics , Ras Homolog Enriched in Brain Protein/genetics , Ras Homolog Enriched in Brain Protein/metabolismABSTRACT
CK2 is a constitutively active Ser/Thr protein kinase, which phosphorylates hundreds of substrates, controls several signaling pathways, and is implicated in a plethora of human diseases. Its best documented role is in cancer, where it regulates practically all malignant hallmarks. Other well-known functions of CK2 are in human infections; in particular, several viruses exploit host cell CK2 for their life cycle. Very recently, also SARS-CoV-2, the virus responsible for the COVID-19 pandemic, has been found to enhance CK2 activity and to induce the phosphorylation of several CK2 substrates (either viral and host proteins). CK2 is also considered an emerging target for neurological diseases, inflammation and autoimmune disorders, diverse ophthalmic pathologies, diabetes, and obesity. In addition, CK2 activity has been associated with cardiovascular diseases, as cardiac ischemia-reperfusion injury, atherosclerosis, and cardiac hypertrophy. The hypothesis of considering CK2 inhibition for cystic fibrosis therapies has been also entertained for many years. Moreover, psychiatric disorders and syndromes due to CK2 mutations have been recently identified. On these bases, CK2 is emerging as an increasingly attractive target in various fields of human medicine, with the advantage that several very specific and effective inhibitors are already available. Here, we review the literature on CK2 implication in different human pathologies and evaluate its potential as a pharmacological target in the light of the most recent findings.
Subject(s)
COVID-19 Drug Treatment , COVID-19 , Cardiovascular Diseases , Casein Kinase II , Cystic Fibrosis , Eye Diseases , Mental Disorders , Protein Kinase Inhibitors/therapeutic use , SARS-CoV-2 , COVID-19/enzymology , COVID-19/genetics , Cardiovascular Diseases/drug therapy , Cardiovascular Diseases/enzymology , Cardiovascular Diseases/genetics , Casein Kinase II/antagonists & inhibitors , Casein Kinase II/genetics , Casein Kinase II/metabolism , Cystic Fibrosis/drug therapy , Cystic Fibrosis/enzymology , Cystic Fibrosis/genetics , Eye Diseases/drug therapy , Eye Diseases/enzymology , Eye Diseases/genetics , Humans , Mental Disorders/drug therapy , Mental Disorders/enzymology , Mental Disorders/genetics , Mutation , Phosphorylation , Signal Transduction/drug effects , Signal Transduction/geneticsABSTRACT
INTRODUCTION: Adaptor-associated kinase 1 (AAK1) has been proposed as being a promising drug target for the treatment of a variety of neurological and psychiatric disorders, such as schizophrenia, cognitive deficits in schizophrenia, Parkinson's disease, bipolar disorder, Alzheimer's disease and neuropathic pain. More recently, AAK1 was shown to be an essential cellular factor for viral replication and therefore has been pursued as a host target for the development of broad-spectrum antiviral agents. AREAS COVERED: This review provides an overview of the patented AAK1 inhibitors from 2013 to present. EXPERT OPINION: The promise of AAK1 as drug target for the treatment of neuropathic pain stimulated the search for AAK1 inhibitors. However, only two companies (i.e. Lexicon Pharmaceuticals and Bristol Myers Squibb) seemed to be active in this field and filed patent applications in the last few years. The most promising congeners showed promising in vitro activity in a variety of AAK1-related assays. Moreover, selected compounds were also endowed with in vivo activity in various preclinical animal models for neuropathic pain.
Subject(s)
Drug Development , Enzyme Inhibitors/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Animals , Antiviral Agents/pharmacology , Humans , Mental Disorders/drug therapy , Mental Disorders/enzymology , Nervous System Diseases/drug therapy , Nervous System Diseases/enzymology , Patents as Topic , Protein Serine-Threonine Kinases/metabolismABSTRACT
The salt-inducible kinases, SIK1, SIK2 and SIK3, most closely resemble the AMP-activated protein kinase (AMPK) and other AMPK-related kinases, and like these family members they require phosphorylation by LKB1 to be catalytically active. However, unlike other AMPK-related kinases they are phosphorylated by cyclic AMP-dependent protein kinase (PKA), which promotes their binding to 14-3-3 proteins and inactivation. The most well-established substrates of the SIKs are the CREB-regulated transcriptional co-activators (CRTCs), and the Class 2a histone deacetylases (HDAC4/5/7/9). Phosphorylation by SIKs promotes the translocation of CRTCs and Class 2a HDACs to the cytoplasm and their binding to 14-3-3s, preventing them from regulating their nuclear binding partners, the transcription factors CREB and MEF2. This process is reversed by PKA-dependent inactivation of the SIKs leading to dephosphorylation of CRTCs and Class 2a HDACs and their re-entry into the nucleus. Through the reversible regulation of these substrates and others that have not yet been identified, the SIKs regulate many physiological processes ranging from innate immunity, circadian rhythms and bone formation, to skin pigmentation and metabolism. This review summarises current knowledge of the SIKs and the evidence underpinning these findings, and discusses the therapeutic potential of SIK inhibitors for the treatment of disease.
Subject(s)
Circadian Rhythm , Mental Disorders/drug therapy , Neoplasms/drug therapy , Osteoporosis/drug therapy , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Humans , Mental Disorders/enzymology , Mental Disorders/pathology , Neoplasms/enzymology , Neoplasms/pathology , Osteoporosis/enzymology , Osteoporosis/pathologyABSTRACT
CaMKII and CaMKIV are calcium/calmodulin-dependent kinases playing a rudimentary role in many regulatory processes in the organism. These kinases attract increasing interest due to their involvement primarily in memory and plasticity and various cellular functions. Although CaMKII and CaMKIV are mostly recognized as the important cogs in a memory machine, little is known about their effect on mood and role in neuropsychiatric diseases etiology. Here, we aimed to review the structure and functions of CaMKII and CaMKIV, as well as how these kinases modulate the animals' behavior to promote antidepressant-like, anxiolytic-like, and procognitive effects. The review will help in the understanding of the roles of the above kinases in the selected neurodegenerative and neuropsychiatric disorders, and this knowledge can be used in future drug design.
Subject(s)
Calcium-Calmodulin-Dependent Protein Kinase Type 2/antagonists & inhibitors , Calcium-Calmodulin-Dependent Protein Kinase Type 4/antagonists & inhibitors , Enzyme Inhibitors/pharmacology , Mental Disorders/drug therapy , Neurodegenerative Diseases/drug therapy , Animals , Humans , Mental Disorders/enzymology , Molecular Targeted Therapy , Neurodegenerative Diseases/enzymologyABSTRACT
Calcium in mammalian neurons is essential for developmental processes, neurotransmitter release, apoptosis, and signal transduction. Incorrectly processed Ca2+ signal is well-known to trigger a cascade of events leading to altered response to variety of stimuli and persistent accumulation of pathological changes at the molecular level. To counterbalance potentially detrimental consequences of Ca2+, neurons are equipped with sophisticated mechanisms that function to keep its concentration in a tightly regulated range. Calcium pumps belonging to the P-type family of ATPases: plasma membrane Ca2+-ATPase (PMCA), sarco/endoplasmic Ca2+-ATPase (SERCA) and secretory pathway Ca2+-ATPase (SPCA) are considered efficient line of defense against abnormal Ca2+ rises. However, their role is not limited only to Ca2+ transport, as they present tissue-specific functionality and unique sensitive to the regulation by the main calcium signal decoding protein-calmodulin (CaM). Based on the available literature, in this review we analyze the contribution of these three types of Ca2+-ATPases to neuropathology, with a special emphasis on mental diseases.
Subject(s)
Calcium-Transporting ATPases/metabolism , Mental Disorders/enzymology , Plasma Membrane Calcium-Transporting ATPases/metabolism , Sarcoplasmic Reticulum Calcium-Transporting ATPases/metabolism , Animals , Calcium-Transporting ATPases/chemistry , Humans , Models, Molecular , Nervous System Diseases/enzymology , Plasma Membrane Calcium-Transporting ATPases/chemistry , Protein Conformation , Sarcoplasmic Reticulum Calcium-Transporting ATPases/chemistryABSTRACT
The calcium/calmodulin-dependent protein kinase II (CaMKII) is a ubiquitous and central player in Ca2+ signaling that is best known for its functions in the brain. In particular, the α isoform of CaMKII has been the subject of intense research and it has been established as a central regulator of neuronal plasticity. In contrast, little attention has been paid to CaMKIIß, the other predominant brain isoform that interacts directly with the actin cytoskeleton, and the functions of CaMKIIß in this organ remain largely unexplored. However, recently, the perturbation of CaMKIIß expression has been associated with multiple neuropsychiatric and neurodevelopmental diseases, highlighting CAMK2B as a gene of interest. Herein, after highlighting the main structural and expression differences between the α and ß isoforms, we will review the specific functions of CaMKIIß, as described so far, in neuronal development and plasticity, as well as its potential implication in brain diseases.
Subject(s)
Brain/enzymology , Calcium-Calmodulin-Dependent Protein Kinase Type 2/genetics , Mental Disorders/genetics , Neurodevelopmental Disorders/genetics , Neuronal Plasticity/physiology , Neurons/enzymology , Animals , Brain/physiopathology , Calcium-Calmodulin-Dependent Protein Kinase Type 2/chemistry , Calcium-Calmodulin-Dependent Protein Kinase Type 2/metabolism , Cell Movement , Gene Expression Regulation , Humans , Isoenzymes/chemistry , Isoenzymes/genetics , Isoenzymes/metabolism , Memory/physiology , Mental Disorders/enzymology , Mental Disorders/physiopathology , Mutation , Neurodevelopmental Disorders/enzymology , Neurodevelopmental Disorders/physiopathology , Neurons/ultrastructure , Signal Transduction , Synapses/enzymology , Synapses/ultrastructureABSTRACT
The enzymatic complex 5α-reductase (5α-R) and 3α/3ß-hydroxysteroid oxidoreductase (HSOR) is expressed in the nervous system, where it transforms progesterone (PROG) and testosterone (T) into neuroactive metabolites. These metabolites regulate myelination, brain maturation, neurotransmission, reproductive behavior and the stress response. The expression of 5α-R and 3α-HSOR and the levels of PROG and T reduced metabolites show regional and sex differences in the nervous system and are affected by changing physiological conditions as well as by neurodegenerative and psychiatric disorders. A decrease in their nervous tissue levels may negatively impact the course and outcome of some pathological events. However, in other pathological conditions their increased levels may have a negative impact. Thus, the use of synthetic analogues of these steroids or 5α-R modulation have been proposed as therapeutic approaches for several nervous system pathologies. However, further research is needed to fully understand the consequences of these manipulations, in particular with 5α-R inhibitors.
Subject(s)
3-Hydroxysteroid Dehydrogenases/physiology , Cholestenone 5 alpha-Reductase/physiology , Progesterone/metabolism , Testosterone/metabolism , 3-Hydroxysteroid Dehydrogenases/genetics , Animals , Brain/enzymology , Cholestenone 5 alpha-Reductase/genetics , Female , Gene Expression , Humans , Male , Mental Disorders/enzymology , Neurodegenerative Diseases/enzymology , Neuroprotective Agents , Sex CharacteristicsABSTRACT
The tryptophan hydroxylase 2 (TPH2) enzyme catalyzes the first step of serotonin biosynthesis. Serotonin is known for its role in several homeostatic systems related to sleep, mood, and food intake. As the reaction catalyzed by TPH2 is the rate-limiting step of serotonin biosynthesis, mutations in TPH2 have been associated with several psychiatric disorders (PD). This work undertakes an in silico analysis of the effects of genetic mutations in the human TPH2 protein. Ten algorithms were used to predict the functional and stability effects of the TPH2 mutations. ConSurf was used to estimate the evolutionary conservation of TPH2 amino acids. GROMACS was used to perform molecular dynamics (MD) simulations of TPH2 WT and P260S, R303W, and R441H, which had already been associated with the development of PD. Forty-six TPH2 variants were compiled from the literature. Among the analyzed variants, those occurring at the catalytic domain were shown to be more damaging to protein structure and function. The ConSurf analysis indicated that the mutations affecting the catalytic domain were also more conserved throughout evolution. The variants S364K and S383F were predicted to be deleterious by all the functional algorithms used and occurred at conserved positions, suggesting that they might be deleterious. The MD analyses indicate that the mutations P206S, R303W, and R441H affect TPH2 flexibility and essential mobility at the catalytic and oligomerization domains. The variants P206S, R303W, and R441H also exhibited alterations in dimer binding affinity and stability throughout the simulations. Thus, these mutations may impair TPH2 functional interactions and, consequently, its function, leading to the development of PD. Furthermore, we developed a database, SNPMOL (http://www.snpmol.org/), containing the results presented in this paper. Understanding the effects of TPH2 mutations on protein structure and function may lead to improvements in existing treatments for PD and facilitate the design of further experiments.
Subject(s)
Computer Simulation , Mental Disorders/enzymology , Mental Disorders/genetics , Mutation/genetics , Tryptophan Hydroxylase/chemistry , Tryptophan Hydroxylase/genetics , Conserved Sequence , Crystallography, X-Ray , Enzyme Stability , Evolution, Molecular , Humans , Hydrogen Bonding , Hydrophobic and Hydrophilic Interactions , Molecular Dynamics Simulation , Principal Component Analysis , Protein Structure, SecondaryABSTRACT
Dopamine beta-hydroxylase (DßH) is an essential neurotransmitter-synthesizing enzyme that catalyzes the formation of norepinephrine (NE) from dopamine and has been extensively studied since its discovery in the 1950s. NE serves as a neurotransmitter in both the central and peripheral nervous systems and is the precursor to epinephrine synthesis in the brain and adrenal medulla. Alterations in noradrenergic signaling have been linked to both central nervous system and peripheral pathologies. DßH protein, which is found in circulation, can, therefore, be evaluated as a marker of norepinephrine function in a plethora of different disorders and diseases. In many of these diseases, DßH protein availability and activity are believed to contribute to disease presentation or select symptomology and are believed to be under strong genetic control. Alteration in the DßH protein by genetic polymorphisms may result in DßH becoming rate-limiting and directly contributing to lower NE and epinephrine levels and disease. With the completion of the human genome project and the advent of next-generation sequencing, new insights have been gained into the existence of naturally occurring DßH sequencing variants (genetic polymorphisms) in disease. Also, biophysical tools coupled with genetic sequences are illuminating structure-function relationships within the enzyme. In this review, we discuss the role of genetic variants in DßH and its role in health and disease.
Subject(s)
Dopamine beta-Hydroxylase/genetics , Dopamine beta-Hydroxylase/metabolism , Genetic Variation/physiology , Animals , Humans , Inflammation/enzymology , Inflammation/genetics , Mental Disorders/enzymology , Mental Disorders/genetics , Neurodegenerative Diseases/enzymology , Neurodegenerative Diseases/genetics , Norepinephrine/genetics , Norepinephrine/metabolismABSTRACT
Neuronal Na+/K+-ATPase is responsible for the maintenance of ionic gradient across plasma membrane. In doing so, in a healthy brain, Na+/K+-ATPase activity accounts for nearly half of total brain energy consumption. The α3-subunit containing Na+/K+-ATPase expression is restricted to neurons. Heterozygous mutations within α3-subunit leads to Rapid-onset Dystonia Parkinsonism, Alternating Hemiplegia of Childhood and other neurological and neuropsychiatric disorders. Additionally, proteins such as α-synuclein, amyloid-ß, tau and SOD1 whose aggregation is associated to neurodegenerative diseases directly bind and impair α3-Na+/K+-ATPase activity. The review will provide a summary of neuronal α3-Na+/K+-ATPase functional properties, expression pattern, protein-protein interactions at the plasma membrane, biophysical properties (distribution and lateral diffusion). Lastly, the role of α3-Na+/K+-ATPase in neurological and neurodegenerative disorders will be discussed. This article is part of the special issue entitled 'Mobility and trafficking of neuronal membrane proteins'.
Subject(s)
Mental Disorders/enzymology , Mental Disorders/genetics , Neurodegenerative Diseases/enzymology , Neurodegenerative Diseases/genetics , Neurons/enzymology , Sodium-Potassium-Exchanging ATPase/biosynthesis , Sodium-Potassium-Exchanging ATPase/genetics , Amino Acid Sequence , Animals , Dystonic Disorders/diagnosis , Dystonic Disorders/enzymology , Dystonic Disorders/genetics , Hemiplegia/diagnosis , Hemiplegia/enzymology , Hemiplegia/genetics , Humans , Membrane Proteins/biosynthesis , Membrane Proteins/genetics , Mental Disorders/diagnosis , Mutation/genetics , Neurodegenerative Diseases/diagnosis , Neurons/pathologyABSTRACT
Sphingomyelin synthases (SMS) catalyze the conversion of ceramide and phosphatidylcholine to sphingomyelin and diacylglycerol and are thus crucial for the balance between synthesis and degradation of these structural and bioactive molecules. SMS thereby play an essential role in sphingolipid metabolism, cell signaling, proliferation and differentiation processes. Although tremendous progress has been made toward understanding the involvement of SMS in physiological and pathological processes, literature in the area of neuropsychiatry is still limited. In this review, we summarize the main features of SMS as well as the current methodologies and tools used for their study and provide an overview of SMS in the central nervous system and their implications in neurological as well as psychiatric disorders. This way, we aim at establishing a basis for future mechanistic as well as clinical investigations on SMS in neuropsychiatric health and diseases.
Subject(s)
Health Status , Mental Disorders/enzymology , Nervous System Diseases/enzymology , Transferases (Other Substituted Phosphate Groups)/metabolism , Animals , Ceramides/metabolism , Humans , Mental Disorders/pathology , Nervous System Diseases/pathology , Phosphatidylcholines/metabolismABSTRACT
An enduring deficit in neurogenesis largely contributes to the development of severe post-traumatic psychiatric disorders such as anxiety, depression, and memory impairment following traumatic brain injury (TBI); however, the mechanism remains obscure. Here we have shown that an imbalance in the generation of γ-aminobutyric acid (GABA)ergic and glutamatergic neurons due to aberrant induction of vesicular glutamate transporter 1 (vGlut1)-positive glutamatergic cells is responsible for impaired neuronal differentiation in the hippocampus following TBI. To elucidate the molecular mechanism, we found that TBI activates a transcription factor, Pax3, by increasing its acetylation status, and subsequently induces Ngn2 transcription. This event, in turn, augments the vGlut1-expressing glutamatergic neurons and accumulation of excess glutamate in the hippocampus that can affect neuronal differentiation. In our study the acetylation of Pax3 was increased due to loss of its interaction with a deacetylase, histone deacetylase 4 (HDAC4), which was downregulated after TBI. TBI-induced activation of GSK3ß was responsible for the degradation of HDAC4. We also showed that overexpression of HDAC4 before TBI reduces Pax3 acetylation by restoring an interaction between HDAC4 and Pax3 in the hippocampus. This event prevents the aberrant induction of vGlut1-positive glutamatergic neurons by decreasing the Ngn2 level and subsequently reinforces the balance between GABAergic and glutamatergic neurons following TBI. Further, we found that overexpression of HDAC4 in the hippocampus improves anxiety, depressive-like behavior, and memory functions following TBI.
Subject(s)
Brain Injuries, Traumatic/enzymology , Down-Regulation/physiology , Histone Deacetylases/metabolism , Mental Disorders/enzymology , Neurogenesis/physiology , Animals , Brain Injuries, Traumatic/pathology , Brain Injuries, Traumatic/psychology , Female , Male , Maze Learning/physiology , Mental Disorders/pathology , Mental Disorders/psychology , Mice , Mice, Inbred C57BLABSTRACT
Steroids exert a profound influence on behavioral reactivity, by modulating the functions of most neurotransmitters and shaping the impact of stress and sex-related variables on neural processes. This background - as well as the observation that most neuroactive steroids (including sex hormones, glucocorticoids and neurosteroids) are synthetized and metabolized by overlapping enzymatic machineries - points to steroidogenic pathways as a powerful source of targets for neuropsychiatric disorders. Inhibitors of steroidogenic enzymes have been developed and approved for a broad range of genitourinary and endocrine dysfunctions, opening to new opportunities to repurpose these drugs for the treatment of mental problems. In line with this idea, preliminary clinical and preclinical results from our group have shown that inhibitors of key steroidogenic enzymes, such as 5α-reductase and 17,20 desmolase-lyase, may have therapeutic efficacy in specific behavioral disorders associated with dopaminergic hyperfunction. While the lack of specificity of these effects raises potential concerns about endocrine adverse events, these initial findings suggest that steroidogenesis modulators with greater brain specificity may hold significant potential for the development of alternative therapies for psychiatric problems. This article is part of the Special Issue entitled 'Drug Repurposing: old molecules, new ways to fast track drug discovery and development for CNS disorders'.
Subject(s)
Drug Repositioning , Mental Disorders/drug therapy , Steroid Synthesis Inhibitors/pharmacology , Steroids/antagonists & inhibitors , 5-alpha Reductase Inhibitors/pharmacology , Animals , Humans , Mental Disorders/enzymology , Mental Disorders/metabolism , Neurotransmitter Agents/pharmacology , Steroid 17-alpha-Hydroxylase/antagonists & inhibitors , Steroids/biosynthesis , Steroids/metabolismABSTRACT
The development of ß+ emitter tracers labelled with carbon-11 or fluorine-18 having optimal characteristics of affinity and selectivity for the phosphodiesterase 10 A protein has received considerable attention, due to the major implication of this enzyme in neurological and psychiatric disorders, such as Hungtington's disease, Parkinson's disease and schizophrenia. The ability to quantify PDE10 A availability in the human brain in vivo will thus aid understanding its role in neurodegenerative and neuropsychiatric pathophysiology as well as providing a valuable tool for drug development. This manuscript reviews the different compound series assessed to date as PET radioligand for the PDE10 A in human and their use to support the development programmes of novel drugs or to evaluate PDE10 A alterations in pathologies as Huntington`s, Parkinson`s Diseases and Schizophrenia.
Subject(s)
Mental Disorders/diagnostic imaging , Mental Disorders/enzymology , Neurodegenerative Diseases/diagnostic imaging , Neurodegenerative Diseases/enzymology , Phosphoric Diester Hydrolases/metabolism , Positron-Emission Tomography/methods , Animals , Brain/diagnostic imaging , Brain/metabolism , Carbon Radioisotopes , Fluorine Radioisotopes , Humans , Phosphoric Diester Hydrolases/analysis , Radioligand Assay/methods , RadiopharmaceuticalsABSTRACT
BACKGROUND: Nitro-oxidative stress (NOS) has been implicated in the pathophysiology of psychiatric disorders. The activity of the polymorphic antioxidant enzyme paraoxonase 1 (PON1) is altered in diseases where NOS is involved. PON1 activity may be estimated using different substrates some of which are influenced by PON1 polymorphisms. OBJECTIVES: 1) to review the association between PON1 activities and psychiatric diseases using a standardized PON1 substrate terminology in order to offer a state-of-the-art review; and 2) to review the efficacy of different strategies (nutrition, drugs, lifestyle) to enhance PON1 activities. METHODS: The PubMed database was searched using the terms paraoxonase 1 and psychiatric diseases. Moreover, the database was also searched for clinical trials investigating strategies to enhance PON1 activity. RESULTS: The studies support decreased PON1 activity as determined using phenylacetate (i.e., arylesterase or AREase) as a substrate, in depression, bipolar disorder, generalized anxiety disorder (GAD) and schizophrenia, especially in antipsychotic-free patients. PON1 activity as determined with paraoxon (i.e., POase activity) yields more controversial results, which can be explained by the lack of adjustment for the Q192R polymorphism. The few clinical trials investigating the influence of nutritional, lifestyle and drugs on PON1 activities in the general population suggest that some polyphenols, oleic acid, Mediterranean diet, no smoking, being physically active and statins may be effective strategies that increase PON1 activity. CONCLUSION: Lowered PON1 activities appear to be a key component in the ongoing NOS processes that accompany affective disorders, GAD and schizophrenia. Treatments increasing attenuated PON1 activity could possibly be new drug targets for treating these disorders.
Subject(s)
Aryldialkylphosphatase/metabolism , Mental Disorders/enzymology , Nitrosative Stress/physiology , Oxidative Stress/physiology , Aryldialkylphosphatase/analysis , Humans , Neurologists , PsychiatryABSTRACT
BACKGROUND: Patients with irritable bowel syndrome (IBS) frequently present with alterations of autonomic activity, especially higher sympathetic activity. Salivary alpha-amylase (sAA) has been implicated as a non-invasive biomarker to reflect the sympathetic activity. Thus, the current study aimed to determine if alterations of sAA secretion could be addressed in IBS patients. METHODS: We recruited twenty-five IBS patients as well as twenty-four age- and sex-matched healthy controls (HCs). Basal and stimulated (by gustatory stimulation with citric acid) saliva samples were collected from each participant, with respective salivary flow rate (SFR) calculated accordingly. Western blotting (WB) was applied to determine the sAA amount by introducing human sAA protein of known quantity. Then the sAA amount ratio was calculated, as expressed by the stimulated sAA amount to basal sAA amount. RESULTS: We observed high variability of the basal and stimulated sAA amount in both groups. An apparently higher prevalence of psychiatric disorders was detected in the IBS group, which was consistent with previous studies. Interestingly, we found elevated basal sAA amount in the IBS patients relative to HCs, which implicated higher sympathetic activities in IBS population. Moreover, we observed blunted sAA response to the gustatory stimulation in the IBS patients, which might be of pathophysiological importance for IBS. CONCLUSION: This is the first attempt to associate sAA secretion with the pathophysiology of IBS. Our results suggest an autonomic dysfunction in IBS patients.
Subject(s)
Autonomic Nervous System Diseases/diagnosis , Autonomic Nervous System Diseases/etiology , Irritable Bowel Syndrome/complications , Irritable Bowel Syndrome/diagnosis , Salivary alpha-Amylases/analysis , Adult , Anxiety Disorders/diagnosis , Anxiety Disorders/enzymology , Biomarkers/analysis , Depressive Disorder, Major/diagnosis , Depressive Disorder, Major/enzymology , Female , Humans , Male , Mental Disorders/diagnosis , Mental Disorders/enzymology , Middle Aged , Salivation/drug effects , Stimulation, ChemicalABSTRACT
BACKGROUND: Multimorbidity in dementia is associated with an increased risk of complications and a higher need for care. Having knowledge of cardiovascular and metabolic comorbidities is crucial when making decisions about diagnostic procedures and therapies. We compared the prevalence of comorbidities in hospitalized patients with Alzheimer's disease (AD), vascular dementia, and psychiatric diseases other than dementia. Additionally, we compared clinically relevant health-care indicators (length of hospital stay, rate of re-hospitalization) between these groups. METHODS: We used information from a database of treatment-relevant indicators from psychiatric and psychosomatic hospitals throughout Germany. This database contains routinely recorded data collected from 85 German hospitals from 2011 to 2015. In total, 14 411 AD cases, 7156 vascular dementia cases, and 34 534 cases involving non-demented psychiatric patients (used as controls) were included. To analyze comorbidities and health-care indicators, χ2 tests and t-tests were used. RESULTS: Diabetes mellitus, lipoprotein disorders, coronary artery diseases, cardiac arrhythmia and insufficiency, and atherosclerosis were significantly more prevalent in patients with vascular dementia than in those with AD and psychiatric controls. Hypertension and coronary artery diseases were less frequently associated with AD than with non-demented psychiatric controls (P < 0.001). Additionally, dementia patients with cardiovascular or metabolic diseases exhibited longer hospital stays (+ 1.4 days, P < 0.001) and were more often re-hospitalized within 3 weeks (P < 0.001) and 1 year (P < 0.001) compared to dementia patients without these comorbidities. CONCLUSIONS: Awareness of somatic comorbidities in patients with dementia is crucial to avoid complications during inpatient treatment. The occurrence of comorbid disorders was associated with longer and more frequent hospital stays, which potentially lead to higher health-care costs. Further studies should evaluate the causative association between somatic comorbidities and inpatient costs in dementia patients.
Subject(s)
Alzheimer Disease/epidemiology , Cardiovascular Diseases/epidemiology , Dementia, Vascular/epidemiology , Mental Disorders/enzymology , Metabolic Syndrome/epidemiology , Patients/statistics & numerical data , Aged , Aged, 80 and over , Alzheimer Disease/diagnosis , Cardiovascular Diseases/diagnosis , Comorbidity , Dementia, Vascular/diagnosis , Female , Germany/epidemiology , Health Care Costs , Humans , Length of Stay/statistics & numerical data , Male , Mental Disorders/diagnosis , Metabolic Syndrome/diagnosis , Middle Aged , PrevalenceABSTRACT
Calcium (Ca2+) ions are prominent cell signaling regulators that carry information for a variety of cellular processes and are critical for neuronal survival and function. Furthermore, Ca2+ acts as a prominent second messenger that modulates divergent intracellular cascades in the nerve cells. Therefore, nerve cells have developed intricate Ca2+ signaling pathways to couple the Ca2+ signal to their biochemical machinery. Notably, intracellular Ca2+ homeostasis greatly relies on the rapid redistribution of Ca2+ ions into the diverse subcellular organelles which serve as Ca2+ stores, including the endoplasmic reticulum (ER). It is well established that Ca2+ released into the neuronal cytoplasm is pumped back into the ER by the sarco-/ER Ca2+ ATPase 2 (SERCA2), a P-type ion-motive ATPase that resides on the ER membrane. Even though the SERCA2 is constitutively expressed in nerve cells, its precise role in brain physiology and pathophysiology is not well-characterized. Intriguingly, SERCA2-dependent Ca2+ dysregulation has been implicated in several disorders that affect cognitive function, including Darier's disease, schizophrenia, Alzheimer's disease, and cerebral ischemia. The current review summarizes knowledge on the expression pattern of the different SERCA2 isoforms in the nervous system, and further discusses evidence of SERCA2 dysregulation in various neuropsychiatric disorders. To the best of our knowledge, this is the first literature review that specifically highlights the critical role of the SERCA2 in the brain. Advancing knowledge on the role of SERCA2 in maintaining neuronal Ca2+ homeostasis may ultimately lead to the development of safer and more effective pharmacotherapies to combat debilitating neuropsychiatric disorders.