Low Levels In Brain Research Articles

Preclinical metabolism and disposition of [14C]GFH009, a novel selective CDK9 inhibitor

GFH009 is a potent and highly selective cyclin-dependent kinase 9 (CDK9) inhibitor currently under phase II clinical trials. In this study, we investigated the metabolism and disposition of GFH009 in Sprague-Dawley (SD) rats, as well as in vitro metabolism of CD-1 mouse, SD rat, beagle dog, cynomolgus monkey, and human. A radiolabelled study indicated that [14C]GFH009 was quickly and widely distributed throughout the body, but presented low levels in brain, testis, and epididymis after a single intravenous dose of 6 mg (100 µCi)/kg to SD rats. GFH009 undergoes systemic metabolic changes, primarily through O-demethylation, oxidation to carboxylic acid and N-dealkylation, cleavage off the methoxyisopropyl moiety being a minor pathway. These metabolic pathways were found to be mainly consistent both in vitro and in vivo. In SD rats, GFH009 was rapidly and completely eliminated, with faeces serving as the major excretion pathway and urine serving as the minor one. Besides, the major clearance pathway for GFH009 was excretion and the minor one was metabolism. GFH009 exhibits favourable drug metabolism and pharmacokinetics (DMPK) properties, which provides valuable insights into the disposition of GFH009 and can be used to guide future clinical studies.

Efficacy in diet-induced obese mice of the hepatotropic, peripheral cannabinoid 1 receptor inverse agonist TM38837.

The cannabinoid CB1 receptor has a well-established role in appetite regulation. Drugs antagonizing central CB1 receptors, most notably rimonabant, induced weight loss and improved the metabolic profile in obese individuals but were discontinued due to psychiatric side effects. However, metabolic benefits were only partially attributable to weight loss, implying a role for peripheral receptors, and peripherally restricted CB1 receptor antagonists have since been of interest. Herein, we describe the evaluation of the peripherally restricted potent CB1 receptor inverse agonists TM38837 and TM39875, with acidic functionality, which were administered daily to diet-induced obese (DIO) mice for 5weeks at doses for which CNS-mediated effects were minimal. Compounds were tested in dose-response in acute studies to compare efficacy (gastric transport) and extent of CNS exposure (hypothermia and satiety sequence) to demonstrate peripheral restriction and select doses for the subsequent chronic DIO study. TM38837 but not TM39875 produced considerable (26%) weight loss, linked to a sustained reduction in food intake, together with improvements in plasma markers of inflammation and glucose homeostasis. Pharmacokinetic analysis indicated high plasma and low brain levels for both compounds with high liver levels for TM38837 (but not TM39875) due to hepatic uptake. Weight loss and metabolic benefits of TM38837 are likely not CNS-mediated but could be linked to enhanced liver exposure, which implicates intracellular CB1 receptors in hepatocytes as a possible driver of obesity and co-morbidities.

Synthesis and evaluation of a 68Ga-labeled spermine derivative for tumor PET imaging

BackgroundThe polyamine transporter system (PTS), which renders it a promising target for tumor therapy and imaging applications, facilitates the transmembrane transport of polyamines. We reported a novel derivative of spermine labeled with gallium-68 ([68Ga]Ga-NOTA-Spermine) for the imaging of the PTS in mouse models of tumor. ResultsThe radiochemical yield of [68Ga]Ga-NOTA-Spermine was determined to be 64–69 %, demonstrating exceptional stability and radiochemical purity (>98 %). Cellular uptake experiments revealed that A549 cells exhibited peak uptake of [68Ga]Ga-NOTA-Spermine at 90 min (15.4 % ± 0.68 %). Biodistribution analysis demonstrated significant accumulation of [68Ga]Ga-NOTA-Spermine in kidneys and liver, while exhibiting low uptake levels in muscle, brain, and bones. Furthermore, Micro-PET/CT scans conducted on A549 tumor-bearing mouse models indicated substantial uptake of [68Ga]Ga-NOTA-Spermine, with maximum tumor/muscle (T/M) ratios reaching 3.71. ConclusionThese results suggest that [68Ga]Ga-NOTA-Spermine holds potential as a PET imaging agent for tumors with high levels of PTS.

Sexual health and serotonin 4 receptor brain binding in unmedicated patients with depression—a NeuroPharm study

Sexual dysfunction is prominent in Major Depressive Disorder (MDD) and affects women with depression more than men. Patients with MDD relative to healthy controls have lower brain levels of the serotonin 4 receptor (5-HT4R), which is expressed with high density in the striatum, i.e. a key hub of the reward system. Reduced sexual desire is putatively related to disturbed reward processing and may index anhedonia in MDD. Here, we aim to illuminate plausible underlying neurobiology of sexual dysfunction in unmedicated patients with MDD. We map associations between 5-HT4R binding, as imaged with [11C]SB207145 PET, in the striatum, and self-reported sexual function. We also evaluate if pre-treatment sexual desire score predicts 8-week treatment outcome in women. From the NeuroPharm study, we include 85 untreated MDD patients (71% women) who underwent eight weeks of antidepressant drug treatment. In the mixed sex group, we find no difference in 5-HT4R binding between patients with sexual dysfunction vs normal sexual function. However, in women we find lower 5-HT4R binding in the sexual dysfunctional group compared to women with normal sexual function (β = −0.36, 95%CI[−0.62:−0.09], p = 0.009) as well as a positive association between sexual desire and 5-HT4R binding (β = 0.07, 95%CI [0.02:0.13], p = 0.012). Sexual desire at baseline do not predict treatment outcome (ROC curve AUC = 52%[36%:67%]) in women. Taken together, we find evidence for a positive association between sexual desire and striatal 5-HT4R availability in women with depression. Interestingly, this raises the question if direct 5-HT4R agonism can target reduced sexual desire or anhedonia in MDD.

Epigenetic aging in adult neurogenesis.

Neural stem cells (NSCs) in the hippocampus generate new neurons throughout life, which functionally contribute to cognitive flexibility and mood regulation. Yet adult hippocampal neurogenesis substantially declines with age and age-related impairments in NSC activity underlie this reduction. Particularly, increased NSC quiescence and consequently reduced NSC proliferation are considered to be major drivers of the low neurogenesis levels in the aged brain. Epigenetic regulators control the gene expression programs underlying NSC quiescence, proliferation and differentiation and are hence critical to the regulation of adult neurogenesis. Epigenetic alterations have also emerged as central hallmarks of aging, and recent studies suggest the deterioration of the NSC-specific epigenetic landscape as a driver of the age-dependent decline in adult neurogenesis. In this review, we summarize the recently accumulating evidence for a role of epigenetic dysregulation in NSC aging and propose perspectives for future research directions.

Neuroprotective Effects of Carbonic Anhydrase Inhibition and Cyclic Adenosine Monophosphate Activation in Mouse Model of Transient Global Cerebral Ischemia and Reperfusion.

Cerebral ischemia is the primary basis of stroke, both sharing common pathogenic origins leading to irreversible brain damage if blood supply is not restored promptly. Existing evidence indicates that carbonic anhydrase (CA) inhibitors (CAIs) may impart therapeutic benefits against ischemia-reperfusion (I/R) pathology via the adenylyl cyclase-cyclic adenosine monophosphate (cAMP) pathway. We hypothesize that CAI and cAMP activation may enhance the therapeutic outcome against I/R conditions. In this investigation, the potential of dichlorphenamide (CAI) and the role of cAMP against ischemia-reperfusion injury were evaluated using a transient global cerebral I/R (tGCI/R) model. Swiss albino mice were subjected to bilateral common carotid artery occlusion (BCCAo) for 20min and reperfusion (R) or sham surgery on day 1. Dichlorphenamide (DCPA, 20mg/kg) and/or forskolin (cAMP agonist, 3mg/kg) was administered intraperitoneally (i.p.) after BCCAo/R for 14days. Results showed that tGCI/R impaired neurocognitive functions and lowered brain levels of cAMP and protein kinase A (PKA) that were ameliorated by DCPA and/or forskolin (FSK). DCPA and/or FSK attenuated tGCI/R-induced brain edema, blood-brain barrier dysfunction, oxidative-nitrosative stress, pro-inflammatory cytokines, acetylcholinesterase activity, cell death, and neurotransmitter imbalance (e.g., glutamate, γ-aminobutyric acid). The study showed that DCPA improved neurological and biochemical parameters against tGCI/R injury via cAMP-PKA-mediated activation of protective mechanisms. However, DCPA and FSK in combination showed much enhanced therapeutic outcomes against tGCI/R. Therefore, CA and cAMP present novel targets that may retard the progress of a transient ischemic attack to a full-blown stroke.

Selective TAAR1 agonists induce conditioned taste aversion.

Trace amine-associated receptor 1 (TAAR1) is the best-studied receptor of trace amines, a group of biogenic amines expressed at a relatively low level in the mammalian brain. Growing evidence suggests that TAAR1 plays a critical role in various neuropsychiatric disorders. Given that selective TAAR1 agonists were shown to produce pro-cognition and antipsychotic-like effects as well as to suppress drug use and relapse, they have been proposed to be novel treatments for mental disorders such as schizophrenia and addiction. However, the aversive effects of selective TAAR1 agonists remain largely unknown. Here, we evaluated whether the selective TAAR1 full agonist RO5166017 and partial agonist RO5263397 could induce conditioned taste aversion (CTA). We found that RO5166017 and RO5263397 produced significant aversions to both saccharin and NaCl taste novelty. Furthermore, RO5166017 produced CTA to saccharin in TAAR1 heterozygous knockout (taar1±) and wild-type rats but not in TAAR1 homozygous knockout rats (taar1-/-), suggesting that TAAR1 was sufficient for the taste aversive stimulus property of RO5166017. Taken together, our data indicate that selective TAAR1 agonists could produce strong CTA. Our study urges careful evaluations of the aversive effects of TAAR1 agonists before translating them to clinical use for the treatment of mental disorders.

Mitigation of cognitive decline and brain pathology after transaortic constriction by Mas agonists

AbstractBackgroundMas and A(1‐7), the endogenous ligand of Mas, were first characterized for their ability to counter regulate the pathological actions of A‐II and AT1R. A(1‐7) has been shown to decrease inflammation and OS and increase cerebral blood flow reactivity. Plasma A(1‐7) levels were decreased in AD patients as compared to age and gender matched controls. Intra‐cerebroventricular (ICV) infusion of A(1‐7) improved cognitive and cerebrovascular function in mice receiving ICV infusion of A‐II. In SAMP8 and in P301S mice, low brain levels of A(1‐7) were correlated with increased tau hyperphosphorylation. However, the short half‐life and lack of oral bioavailability of A(1‐7) make it challenging to develop as a therapeutic modality. In order to overcome this shortcoming, our lab has developed equipotent small molecule analogs of A(1‐7), RASRx1902 and RASRx1911.MethodC57/Bl6 mice underwent transaortic constriction (TAC). One week later, echocardiography was performed and the animals randomized based on their TAC gradient and treatment (vehicle or 2 mg/kg RASx1902 or RASRx 1911 subcutaneously, once daily for 12 weeks. After 10 weeks of treatment, the mice underwent novel object recognition. At necropsy, brain tissue was analyzed by flow cytometry and levels of inflammatory cytokines by MSD.ResultTAC surgery alone resulted in reduced cognitive function measured by NOR. This cognitive decline was reversed by RASRx1902 and RASRx1911 treatment. Treatment with RASRx1902 and RASRx1911 also reduced the levels of microglial and neuronal mitochondrial dysfunction, oxidative stress (OS) and inflammation seen in saline treated mice to levels comparable to sham controls.ConclusionIn conclusion, RASRx1902 and RASRx1911 resulted in improved cognition and reduced OS and inflammation in the brain of mice that had undergone TAC surgery.

Potential of Ligands for Trace Amine-Associated Receptor 1 (TAAR1) in the Management of Substance Use Disorders.

Trace amines, including β-phenylethylamine (β-PEA), p-tyramine (TYR), tryptamine (TRP), and p-octopamine (OCT), represent a group of amines expressed at low levels in the mammalian brain. Given the close structural similarities to traditional monoamines, links between trace amines and the monoaminergic system have long been suspected. Trace amine-associated receptor 1 (TAAR1), the most well characterized receptor in the TAAR family, has been shown to be potently activated by trace amines such as TYR and PEA. Further, catecholamine metabolites and amphetamine analogs are also potent agonists of TAAR1, implicating the receptor in mediating the monoaminergic system and in substance use disorders. In the central nervous system, TAAR1 is expressed in brain regions involved in dopaminergic, serotonergic, and glutamatergic transmission, and genetic animal models and electrophysiological studies have revealed that TAAR1 is a potent modulator of the monoaminergic system. Selective and potent engineered TAAR1 ligands, including full (RO5166017 and RO5256390) and partial (RO5203648, RO5263397 and RO5073012) agonists and the antagonist EPPTB (N-(3-ethoxyphenyl)-4-(1-pyrrolidinyl)-3-(trifluoromethyl) benzamide, RO5212773), serve as invaluable tools for the investigation of TAAR1 functions and display significant potential for the development of TAAR1-based pharmacotherapies for the treatment of substance use disorders. Despite a number of advances that have been made, more clinical studies are warranted in order to test the potential and efficacy of TAAR1 ligands in the treatment of psychiatric disorders, including substance use disorders.

Serum Amyloid Beta42 Is Not Eliminated by the Cirrhotic Liver: A Pilot Study.

Amyloid-beta (Aβ) deposition in the brain is the main pathological hallmark of Alzheimer disease. Peripheral clearance of Aβ may possibly also lower brain levels. Recent evidence suggested that hepatic clearance of Aβ42 is impaired in liver cirrhosis. To further test this hypothesis, serum Aβ42 was measured by ELISA in portal venous serum (PVS), systemic venous serum (SVS), and hepatic venous serum (HVS) of 20 patients with liver cirrhosis. Mean Aβ42 level was 24.7 ± 20.4 pg/mL in PVS, 21.2 ± 16.7 pg/mL in HVS, and 19.2 ± 11.7 pg/mL in SVS. Similar levels in the three blood compartments suggested that the cirrhotic liver does not clear Aβ42. Aβ42 was neither associated with the model of end-stage liver disease score nor the Child–Pugh score. Patients with abnormal creatinine or bilirubin levels or prolonged prothrombin time did not display higher Aβ42 levels. Patients with massive ascites and patients with large varices had serum Aβ42 levels similar to patients without these complications. Serum Aβ42 was negatively associated with connective tissue growth factor levels (r = −0.580, p = 0.007) and a protective role of Aβ42 in fibrogenesis was already described. Diabetic patients with liver cirrhosis had higher Aβ42 levels (p = 0.069 for PVS, p = 0.047 for HVS and p = 0.181 for SVS), which is in accordance with previous reports. Present analysis showed that the cirrhotic liver does not eliminate Aβ42. Further studies are needed to explore the association of liver cirrhosis, Aβ42 levels, and cognitive dysfunction.

Novel Targets of SARS-CoV-2 Spike Protein in Human Fetal Brain Development Suggest Early Pregnancy Vulnerability.

Pregnant women are at greater risk of infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), because of their altered immunity and strained cardiovascular system. Emerging studies of placenta, embryos, and cerebral organoids suggest that fetal organs including brain could also be vulnerable to coronavirus disease 2019 (COVID-19). Additionally, a case study from Paris has reported transient neurological complications in neonates born to pregnant mothers. However, it remains poorly understood whether the fetal brain expresses cellular components that interact with Spike protein (S) of coronaviruses, which facilitates fusion of virus and host cell membrane and is the primary protein in viral entry. To address this question, we analyzed the expression of known (ACE2, TMPRSS2, and FURIN) and novel (ZDHHC5, GOLGA7, and ATP1A1) S protein interactors in publicly available fetal brain bulk and single cell RNA sequencing datasets. Bulk RNA sequencing analysis across multiple regions of fetal brain spanning 8 weeks post conception (wpc)−37wpc indicates that two of the known S protein interactors are expressed at low levels with median normalized gene expression values ranging from 0.08 to 0.06 (ACE2) and 0.01–0.02 (TMPRSS2). However, the third known S protein interactor FURIN is highly expressed (11.1–44.09) in fetal brain. Interestingly, all three novel S protein interactors are abundantly expressed throughout fetal brain development with median normalized gene expression values ranging from 20.38–21.60 (ZDHHC5), 92.47–68.35 (GOLGA7), and 65.45–194.5 (ATP1A1). Moreover, the peaks of expression of novel interactors is around 12–26wpc. Using publicly available single cell RNA sequencing datasets, we further show that novel S protein interactors show higher co-expression with neurons than with neural progenitors and astrocytes. These results suggest that even though two of the known S protein interactors are present at low levels in fetal brain, novel S protein interactors are abundantly present and could play a direct or indirect role in SARS-CoV-2 fetal brain pathogenesis, especially during the 2nd and 3rd trimesters of pregnancy.

The Difference of Brain Derivat Neutrophic Factor of Mus Musculus Newborn from Adolescent and Adult Pregnancy

Background: The brain is the main organ involved in stress adaptation, while being the target of stress. Stress activates the hypothalamic-pituitary-adrenal (HPA) axis and the system is adrenomedular Simpato thereby increasing the production of corticotropin-releasing hormone (CRH) and arginine-vasopressin (AVP) resulting in lower levels of Brain Derived Neurotrophic Factor (BDNF) in the hippocampus. Objective: The study aims to find out the difference of BDNFof Mus musculus newborn brain fromadolescents and adults pregnancy. Method: The samples on this study were 32 mice that divided by 2 groups were adolescent pregnancy mice group and adult pregnancy mice group. Mus musculus newborn were born by sectio and selected three with the heaviest, medium and lightest of each mothers to sacrificed their brains did decapitated and made immunohypochemical preparations and continued examination of the Immunoreactive Score to calculate Brain Derived Neurotrophic Factor expression. Result: BDNF expression of adolescent pregnancy mice group had higher (5.65±1.044) than adult pregnancy mice group (4.15±1,049). Test results showed that there was differences of BDNF expression in the brain p = 0,000 (p< 0.05) with details, there were differences in the cerebrum p = 0,015 and the cerebellum p = 0,000 between adolescent pregnancy mice group and adult pregnancy mice group. Conclusion: BDNF expression in brain of Mus musculus newborn from adolescent pregnancy lower than Mus musculus newborn from adult pregnancy.

Recapitulation of the EEF1A2 D252H neurodevelopmental disorder-causing missense mutation in mice reveals a toxic gain of function.

Heterozygous de novo mutations in EEF1A2, encoding the tissue-specific translation elongation factor eEF1A2, have been shown to cause neurodevelopmental disorders including often severe epilepsy and intellectual disability. The mutational profile is unusual; ~50 different missense mutations have been identified but no obvious loss of function mutations, though large heterozygous deletions are known to be compatible with life. A key question is whether the heterozygous missense mutations operate through haploinsufficiency or a gain of function mechanism, an important prerequisite for design of therapeutic strategies. In order both to address this question and to provide a novel model for neurodevelopmental disorders resulting from mutations in EEF1A2, we created a new mouse model of the D252H mutation. This mutation causes the eEF1A2 protein to be expressed at lower levels in brain but higher in muscle in the mice. We compared both heterozygous and homozygous D252H and null mutant mice using behavioural and motor phenotyping alongside molecular modelling and analysis of binding partners. Although the proteomic analysis pointed to a loss of function for the D252H mutant protein, the D252H homozygous mice were more severely affected than null homozygotes on the same genetic background. Mice that are heterozygous for the missense mutation show no behavioural abnormalities but do have sex-specific deficits in body mass and motor function. The phenotyping of our novel mouse lines, together with analysis of molecular modelling and interacting proteins, suggest that the D252H mutation results in a gain of function.

Efficacy of a novel potent and high water-soluble selective PARP inhibitor CVL218 in glioma.

e13539 Background: Glioma is the most common, deadly, and difficult-to-treat intracranial tumor. Up to 70% of gliomas are found to carry isocitrate dehydrogenase (IDH) mutations, which induce a homologous recombination defect (HRD) that renders glioma cells sensitive to poly (ADP-ribose) polymerase inhibitors (PARPi). However, 4 launched PARPi have limitation for IDH-mutant glioma because of low concentration level in brain. CVL218 is a novel potent and high water-soluble selective PARP-1/2 inhibitor. Pharmacokinetic studies in rats showed that CVL218 can easily across the BBB, has 10 times higher concentration in brain than in the plasma, indicating its therapeutic potential in glioma. Here, we examined its effect on glioma in vitro and in vivo. Methods: BT142 mut/- glioma cells with a homozygous IDH1 R132H mutation were exploited. Chemotherapeutic agent temozolomide (TMZ), PARPi Olaparib and Niraparib, were used as controls. The inhibition of BT142 cell growth by compounds in vitro was measured by MTT assay. Female NOD/SCID mice with orthotopic xenografts of BT142 glioma cells were used to evaluate the antitumor efficacy of compounds in vivo. Medium survival time (MST) was compared using the Kaplan-Meier method and logrank test. Results: CVL218 inhibited the BT142 cell growth in vitro with an IC50 of 2.07 ± 0.62 μM, better than Olaparib and Niraparib. Orthotopic xenograft glioma mice model study showed that CVL218 group significantly extended the MST to 98.0 days ( p= 0.0206), while MST of TMZ treated group is 85.0 days. Conclusions: CVL218 inhibits IDH1-mutant BT142 glioma cell growth in vitro and in vivo. The present findings suggest that CVL218 is a potential agent which could be useful as a treatment for IDH-mutant glioma. We will start its phase I clinical study for glioma soon.

Metal-Enhanced Near Infrared Fluorescence-Based Sensor with Highly Improved Sensitivity for Adenosine Triphosphate

Near infrared (NIR) fluorescent sensor for biologically important analyte is very promising because NIR fluorescence imaging has minimal autofluorescence and high tissue penetration in living system. Nevertheless, its low fluorescence quantum yield leads to low sensitivity of detection. In this study, a functionalized gold nanorods (NIR-AuNRs-3) plasmon enhanced NIR fluorescence-based sensor for adenosine triphosphate (ATP) was developed with highly improved sensitivity. The fluorescence quantum yield with ATP was significantly enhanced, from almost zero to 0.61, resulting in remarkable enhancement of sensitivity. This was attributed to the increase of radiative decay rate of NIR dye by 30-fold, along with almost unchanged nonradiative decay rate. The limit of detection for ATP was 0.6 nM, and it was successfully applied to determine low ATP levels (10.1 ± 2.6 nM) in rat brain. It has been also demonstrated to be useful for monitoring intracellular ATP levels with high sensitivity.

Role of Myo‐inositol in Ischemic Stroke Outcome in a Type 2 Diabetic Mouse Model

Stroke is the leading cause of disability in the United States; ischemic stroke is the common form that occurs in 87% of all strokes. It has been reported that an increase in brain edema after ischemic stroke worsens long‐term clinical outcome. Myo‐inositol (MI), a major organic osmolyte that promotes cell membrane stability and various cellular functions, has been reported to be detected at lower brain levels in stroke patients. Furthermore, glucose can compete with MI transport which could lead to further lowering of brain levels of MI in diabetic patients which is compounded with higher brain edema reported in diabetic stroke patients. Therefore, understanding the relationship between MI and diabetic stroke injury is vital. In this study, we investigated the role of MI transporters during stroke and post‐stroke outcomes especially related to the role of glial cells and post‐stroke reorganization. Our hypothesis is that MI plays a putative role in recovery of motor function after stroke. Restoration of activity in the primary motor cortex has been associated with better motor function in stroke patients. Primary astrocytes were used for in vitro studies and middle cerebral artery occlusion (MCAO) mouse model for in vivo stroke studies. Immunocytochemistry (ICC) studies showed that astrocytes express sodium dependent myo‐inositol transporter 1 (SMIT1) and sodium‐dependent glucose transporter 6 (SGLT6) transporters and level of expression changed in a time‐dependent manner during oxygen‐glucose deprivation (OGD). Further, this was confirmed by time‐dependent uptake of MI during normoxic and OGD conditions. Preliminary animal studies demonstrated that post‐stroke administration of MI attenuated infarction size and edema ratios in a db/db mouse model of type 2 diabetes compared to nondiabetic ischemic animals and also improved motor function in behavioral tests. This preliminary data suggests that myo‐inositol may have a neuroprotective role in ischemic stroke injury and could significantly improve stroke outcome. More studies are required to understand the neuroprotective mechanisms of MI in stroke injury.Support or Funding InformationRO1 NS070612This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Molecular cloning and functional analysis of Growth arrest and DNA damage-inducible 45 aa and ab (Gadd45aa and Gadd45 ab) in Ctenopharyngodon idella

The Gadd45aa and Gadd45 ab genes are members of the Gadd45 family, which are critically involved in immunological and apoptosis functions. In this study, we isolated and characterized Gadd45aa and Gadd45 ab cDNA from grass carp (Ctenopharyngodon idella) (designated CiGadd45aa and CiGadd45 ab). The CiGadd45aa and CiGadd45 ab fragments spanned 1272 bp/1248 bp, which contained 474 bp/480 bp open reading frames encoding 157/159 amino acid proteins. BLAST analysis revealed that CiGadd45aa and CiGadd45 ab shared high similarity with known Gadd45a sequences. qRT-PCR analysis showed widespread and abundant expression of CiGadd45aa in gill, intestine, kidney, brain, blood, skin and fin, but low in liver, spleen, head kidney, heart, and muscle. CiGadd45 ab was expressed highly in liver, spleen and blood but at low levels in gill, intestine, kidney, head kidney, heart, brain, skin, muscle, and fin. Following challenge of grass carp with Aeromonas hydrophila, CiGadd45aa and CiGadd45 ab expression was upregulated. In immune-relevant tissues and MAPK family genes (p38, JNK and ERK) were upregulated by CiGadd45aa and CiGadd45 ab overexpression and partly downregulated by interfered in the CIK grass carp kidney cell line. In addition, transcription of the cytokine-encoding il-8 gene was upregulated/downregulated by CiGadd45aa and CiGadd45 ab overexpression and interference. These results suggest that CiGadd45aa and CiGadd45 ab play roles in innate immune responses against A. hydrophila in grass carp.

Embryonic exposure to valproic acid affects the histaminergic system and the social behaviour of adult zebrafish (Danio rerio).

Histamine modulates several behaviours and physiological functions, and its deficiency is associated with neuropsychiatric disorders. Gestational intake of valproic acid (VPA) is linked to autism spectrum disorder (ASD), characterized by impaired sociability and stereotypies. VPA effects on the neurochemistry and functional morphology of the histaminergic system in ASD are unclear. Zebrafish are highly social, and given the similarities between zebrafish and human neurotransmitter systems, we have studied the effects of VPA on histamine in zebrafish. Histaminergic, dopaminergic and noradrenergic systems of larval and adult zebrafish exposed to VPA from the end of gastrulation until neural tube formation were studied using HPLC, quantitative PCR, immunocytochemistry and in situ hybridization. Sociability, dark-flash response and locomotion were also studied. Zebrafish larvae exposed to VPA showed decreased locomotion and an abnormal dark-flash response. Additionally, a reduced number of histaminergic neurons, low histamine and altered mRNA expression of key genes of the monoaminergic systems were also detected. The reduced mRNA expression of genes of the studied systems persisted until adulthood. Furthermore, adult VPA-exposed animals presented lower brain levels of noradrenaline and 3,4-dihydroxyphenylacetic acid, along with impaired sociability. VPA exposure in early development causes molecular and neurochemical alterations in zebrafish, which persist into adulthood and accompany impaired sociability. These findings will highlight the possible involvement of the histaminergic system in outcomes related to neuropsychiatric disorders. Furthermore, it supports zebrafish as a tool to investigate mechanisms underlying these disorders.

Role of efflux transporters in the absorption, distribution and elimination in rodents of a novel PDE4 inhibitor, CHF6001

CHF6001 is a new and potent PDE4 inhibitor for the treatment of human lung diseases, designed for topical administration by inhalation. In preclinical assessment CHF6001 appeared safe and devoid of emetic effect, which is typical side effect of PDE4 inhibitors in humans.CHF6001 absorption, distribution and excretion were evaluated in rats by PO and IV administration of [14C]CHF6001; additionally the role of transporters was investigated by using transfected cells expressing either human transporters or MDR1 and BCRP KO mice.[14C]CHF6001 intravenously administered as bolus distributed in all the tissues (with very low levels in brain and fetus) and it was mainly eliminated in bile. Following oral administration [14C]CHF6001 about half of the dose was absorbed through the gut.In vitro, CHF6001 was a substrate of human membrane transporters MDR1 and BCRP.In wild and BCRP KO mice CHF6001 was not detectable in brain, whereas it was measurable in Mdr1a/b KO mice.Therefore, in animal species Mdr1a/b plays a significant role in CHF6001 disposition, limiting its distribution into brain and contributing to the safety profile observed in preclinical evaluation.This behavior was confirmed by the results of the first human studies, where CHF6001 was safe and with no emetic effect at all the evaluated doses.

Early-onset behavioral and neurochemical deficits in the genetic mouse model of phenylketonuria.

Phenylketonuria (PKU) is one of the most common human inborn errors of metabolism, caused by phenylalanine hydroxylase deficiency, leading to high phenylalanine and low tyrosine levels in blood and brain causing profound cognitive disability, if untreated. Since 1960, population is screened for hyperphenylalaninemia shortly after birth and submitted to early treatment in order to prevent the major manifestations of the disease. However, the dietetic regimen (phenylalanine free diet) is difficult to maintain, and despite the recommendation to a strict and lifelong compliance, up to 60% of adolescents partially or totally abandons the treatment. The development and the study of new treatments continue to be sought, taking advantage of preclinical models, the most used of which is the PAHenu2 (BTBR ENU2), the genetic murine model of PKU. To date, adult behavioral and neurochemical alterations have been mainly investigated in ENU2 mice, whereas there are no clear indications about the onset of these deficiencies. Here we investigated and report, for the first time, a comprehensive behavioral and neurochemical assay of the developing ENU2 mice. Overall, our findings demonstrate that ENU2 mice are significantly smaller than WT until pnd 24, present a significant delay in the acquisition of tested developmental reflexes, impaired communicative, motor and social skills, and have early reduced biogenic amine levels in several brain areas. Our results extend the understanding of behavioral and cerebral abnormalities in PKU mice, providing instruments to an early preclinical evaluation of the effects of new treatments.