Mu-opioid receptor agonism differentially alters social behaviour and immediate early gene expression in male adolescent rats prenatally exposed to valproic acid versus controls.

Mu-opioid receptors (MOPs) mediate and modulate social reward and social interaction. However, few studies have examined the functionality of this system in rodent models of social impairment. Deficits in social motivation and cognition are observed in rodents following pre-natal exposure to the anti-epileptic valproic acid (VPA), however it is not known whether MOP functionality is altered in these animals. The present study examined the effects of acute administration of the prototypical MOP agonist morphine (1 mg/kg) on social behavioural responding in the 3-chamber test and immediate early gene expression in adolescent rats (postnatal day 28-43) prenatally exposed to VPA vs saline-exposed controls. Pharmacokinetic analysis of morphine concentration, MOP binding and expression were also examined. The data revealed that sociability and social novelty preference in the 3-chamber test were reduced in rats prenatally exposed to VPA compared to saline-exposed control counterparts. Morphine reduced both sociability and social novelty preference behaviour in saline-, but not VPA-, exposed rats. Analysis of immediate early gene expression revealed that morphine reduced the expression of cfos in the prefrontal cortex of both saline- and VPA-exposed rats and reduced expression of cfos and junb in the hippocampus of VPA-exposed rats only. Pharmacokinetic analysis revealed similar concentrations of morphine in the plasma and brain of both saline- and VPA-exposed rats and similar thalamic MOP occupancy levels. Gene and protein expression of MOP in prefrontal cortex and hippocampus did not differ between saline and VPA-exposed rats. These data indicate differential effects of morphine on social responding and immediate early gene expression in the hippocampus of VPA-exposed rats compared with saline-exposed controls. This study provides support for altered MOP functionality in rats prenatally exposed to VPA, which may underlie the social deficits observed in the model.

Cocaine-induced Fos expression in the rat brain: Modulation by prior Δ9-tetrahydrocannabinol exposure during adolescence and sex-specific effects.

It has been suggested that cannabis consumption during adolescence may be an initial step to cocaine use in adulthood. Indeed, previous preclinical data show that adolescent exposure to cannabinoids (both natural and synthetic) potentiates cocaine self-administration in rats. Here we aimed at gaining a deeper understanding of the cellular activation patterns induced by cocaine as revealed by Fos imaging and how these patterns may change due to adolescent exposure to THC. Male and female Wistar rats were administered every other day THC (3 mg/kg i.p.) or vehicle from postnatal day 28-44. At adulthood (PND90) they were given an injection of cocaine (20 mg/kg i.p.) or saline and sacrificed 90 min later. Cocaine-induced Fos activation was measured by immunohistochemistry as an index of cellular activation. We found that cocaine-induced activation in the motor cortex was stronger in THC-exposed rats. Moreover, there was significant sex-dependent interaction between cocaine and adolescent THC exposure in the dorsal hypothalamus, suggesting that cocaine induced a more robust cellular activation in THC-exposed females but not in THC-treated males. Other THC- and cocaine-induced effects were also evident. These results add to the previous literature suggesting that the behavioral, cellular, molecular, and brain-activating actions of cocaine are modulated by early experience with cannabinoids and provide additional knowledge that may explain the enhanced actions of cocaine in rats exposed to cannabinoids during their adolescence.

Effects of tacrolimus on c-fos in hippocampus and memory performances in streptozotocin model of Alzheimer's disease of rats

Background/aim: Calcineurin, an inhibitor of calcium dependent phosphatase is highly presented in a brain of an Alzheimer's disease. Aging brain gets more sensitive to hyperactivation of calcineurin, and this event causes tau neurofibrillary plaque accumulation, which is one of the outcomes of this disease. The regions of hippocampus are much effected from the results of this process. Our hypothesis is that a calcineurin inhibitor, tacrolimus, could prevent the accumulation and the decrease of the neuronal cells. Therefore, this immunosuppressive drug could be a candidate for an early treatment of Alzheimer disease. Materials and methods: Fifteen male Wistar albino rats were divided to three groups; control, Alzheimer, and Alzheimer+Tacrolimus. The Alzheimer group received an injection of streptozotocin intracerebroventricularly for the purpose of modelling the disease via generating free radicals leading a cognitive impairment. Alzheimer+Tacrolimus group first received an oral drug, a calcineurin inhibitor for 10 days afterwards prepared for the model as same as the Alzheimer group received. Finally, all groups performed the Morris water maze test for four days then sacrificed. For the aim of counting neurons in the hippocampus stereological methods, as well as for an evaluation of cellular response to stress in dentate gyrus, a c-Fos immunohistochemistry was performed. Results: According to the probe trial of Morris water maze test, the latency time was dramatically higher at both Alzheimer and Alzheimer+Tacrolimus group (p < 0.01). We confirmed these results with our stereology data. The results from stereology technique indicate that there was a neuronal decrease at the hippocampus regions in Alzheimer and Alzheimer+Tacrolimus group. Our outcomes from immunohistochemical data showed a significant increase in the number of c-Fos-positive cells in Alzheimer group when comparing with Alzheimer+Tacrolimus group (p < 0.001). Conclusion: There was none preventive effect for neuronal loss in the hippocampus under the effect of tacrolimus drug according to stereological results. However, tacrolimus administration may have reduced cellular stress and cell damage.

Glucocorticoids attenuate interleukin-6-induced c-Fos and Egr1 expression and impair neuritogenesis in PC12 cells.

Interleukin-6 (IL-6) is a cytokine primarily known for immune regulation. There is also growing evidence that IL-6 triggers neurogenesis and impacts neural development, both life-long occurring processes that can be impaired by early-life and adult stress. Stress induces the release of glucocorticoids by activation of the hypothalamic-pituitary-adrenal (HPA) axis. On the cellular level, glucocorticoids act via the ubiquitously expressed glucocorticoid receptor. Thus, we aimed to elucidate whether glucocorticoids affect IL-6-induced neural development. Here, we show that IL-6 signalling induces neurite outgrowth in adrenal pheochromocytoma PC12 cells in a mitogen-activated protein kinase (MAPK) pathway-dependent manner, since neurite outgrowth was diminished upon Mek-inhibitor treatment. Using quantitative biochemical approaches, such as qRT-PCR analysis of Hyper-IL-6 treated PC12 cells, we show that neurite outgrowth induced by IL-6 signalling is accompanied by early and transient MAPK-dependent mRNA expression of immediate early genes coding for proteins such as early growth response protein 1 (Egr1) and c-Fos. This correlates with reduced proliferation and prolonged G0/G1 cell cycle arrest as determined by monitoring the cellular DNA content using flow cytometry. These results indicate for IL-6 signalling-induced neural differentiation. Interestingly, the glucocorticoid Dexamethasone impairs early IL-6 signalling-induced mRNA expression of c-Fos and Egr1 and restrains neurite outgrowth. Impaired Egr1 and c-Fos expression in neural development is implicated in the aetiology of neuropathologies. Thus, it appears likely that stress-induced release of glucocorticoids, as well as therapeutically administered glucocorticoids, contribute to the development of neuropathologies by reducing the expression of Egr1 and c-Fos, and by restraining IL-6-dependent neural differentiation.

Neuronal mechanisms of adenosine A2A receptors in the loss of consciousness induced by propofol general anesthesia with functional magnetic resonance imaging.

Propofol is the most common intravenous anesthetic agent for induction and maintenance of anesthesia, and has been used clinically for more than 30 years. However, the mechanism by which propofol induces loss of consciousness (LOC) remains largely unknown. The adenosine A2A receptor (A2A R) has been extensively proven to have an effect on physiological sleep. It is, therefore, important to investigate the role of A2A R in the induction of LOC using propofol. In the present study, the administration of the highly selective A2A R agonist (CGS21680) and antagonist (SCH58261) was utilized to investigate the function of A2A R under general anesthesia induced by propofol by means of animal behavior studies, resting-state magnetic resonance imaging and c-Fos immunofluorescence staining approaches. Our results show that CGS21680 significantly prolonged the duration of LOC induced by propofol, increased the c-Fos expression in nucleus accumbens (NAc) and suppressed the functional connectivity of NAc-dorsal raphe nucleus (DR) and NAc-cingulate cortex (CG). However, SCH58261 significantly shortened the duration of LOC induced by propofol, decreased the c-Fos expression in NAc, increased the c-Fos expression in DR, and elevated the functional connectivity of NAc-DR and NAc-CG. Collectively, our findings demonstrate the important roles played by A2A R in the LOC induced by propofol and suggest that the neural circuit between NAc-DR maybe controlled by A2A R in the mechanism of anesthesia induced by propofol.

Pharmacology profile of F17464, a dopamine D3 receptor preferential antagonist.

F17464 (N-(3-{4-[4-(8-Oxo-8H-[1,3]-dioxolo-[4,5-g]-chromen-7-yl)-butyl]-piperazin-1-yl}-phenyl)-methanesulfonamide, hydrochloride) is a new potential antipsychotic with a unique profile. The compound exhibits high affinity for the human dopamine receptor subtype 3 (hD3) (Ki = 0.17 nM) and the serotonin receptor subtype 1a (5-HT1a) (Ki = 0.16 nM) and a >50 fold lower affinity for the human dopamine receptor subtype 2 short and long form (hD2s/l) (Ki = 8.9 and 12.1 nM, respectively). [14C]F17464 dynamic studies show a slower dissociation rate from hD3 receptor (t1/2 = 110 min) than from hD2s receptor (t1/2 = 1.4 min) and functional studies demonstrate that F17464 is a D3 receptor antagonist, 5-HT1a receptor partial agonist. In human dopaminergic neurons F17464 blocks ketamine induced morphological changes, an effect D3 receptor mediated. In vivo F17464 target engagement of both D2 and 5-HT1a receptors is demonstrated in displacement studies in the mouse brain. F17464 increases dopamine release in the rat prefrontal cortex and mouse lateral forebrain - dorsal striatum and seems to reduce the effect of MK801 on % c-fos mRNA medium expressing neurons in cortical and subcortical regions. F17464 also rescues valproate induced impairment in a rat social interaction model of autism. All the neurochemistry and behavioural effects of F17464 are observed in the dose range 0.32-2.5 mg/kg i.p. in both rats and mice. The in vitro - in vivo pharmacology profile of F17464 in preclinical models is discussed in support of a therapeutic use of the compound in schizophrenia and autism.

Role of orbitofrontal cortex in incubation of oxycodone craving in male rats.

One of the main challenges in treating opioid-use disorders is relapse during abstinence, triggered by re-exposure to drug-associated cues. Previous studies have demonstrated that drug-seeking in rats progressively increases over time during withdrawal (incubation of drug craving). Here, we used male rats and examined neural mechanisms underlying incubation of craving to oxycodone, a commonly abused prescription opioid, and we focused on orbitofrontal cortex (OFC), a brain region previously implicated in incubation of heroin craving. We first used neuronal activity marker Fos and measured neuronal activation in OFC (ventral and lateral OFC) associated with day-1 and day-15 relapse tests. Next, we determined the effect of pharmacological reversible inactivation of OFC on incubated oxycodone seeking on withdrawal day 15. Finally, we determined the effect of reversible inactivation of OFC on nonincubated oxycodone seeking on withdrawal day 1. We found that lever presses during relapse tests were higher on withdrawal day 15 than on withdrawal day 1 (incubation of oxycodone craving). Incubation of oxycodone craving is accompanied with a time-dependent increase of Fos protein expression in both ventral and lateral OFC. Lastly, OFC inactivation decreased oxycodone seeking on withdrawal day 15 but had no effect on withdrawal day 1. Together with the previous heroin study, results here show that OFC plays a critical role in incubation of opioid craving.

Role of prefrontal cortex projections to the nucleus accumbens core in mediating the effects of ceftriaxone on cue-induced cocaine seeking.

Ceftriaxone is an antibiotic that reliably attenuates the reinstatement of cocaine seeking after extinction while preventing the nucleus accumbens (NA) core glutamate efflux that drives reinstatement. However, when rats undergo abstinence without extinction, ceftriaxone attenuates context-primed cocaine seeking but NA core glutamate efflux still increases. Here, we sought to determine if the same would occur when cocaine seeking is prompted by both context and discrete cues (cue-induced seeking) after cocaine abstinence. Male rats self-administered intravenous cocaine accompanied by drug-associated cues (light + tone) for 2 h/day for 14 days. Rats then experienced abstinence with daily handling but no extinction training for 2 weeks. Ceftriaxone (200 mg/kg IP) or vehicle was administered during the last 6 days of abstinence. During a cue-induced cocaine seeking test, microdialysis procedures were conducted. Rats were perfused at the end of the test for later Fos analysis. A separate cohort of rats was infused with the retrograde tracer cholera toxin B in the NA core and underwent the same self-administration and relapse procedures. Ceftriaxone increased baseline glutamate and attenuated both cue-induced cocaine seeking and NA core glutamate efflux during this test. Ceftriaxone reduced Fos expression in regions sending projections to the NA core (prefrontal cortex, basolateral amygdala, ventral tegmental area) and specifically reduced Fos in prelimbic cortex and not infralimbic cortex neurons projecting to the NA core. Thus, when cocaine seeking is induced by drug-associated cues, ceftriaxone is able to attenuate relapse by preventing NA core glutamate efflux, likely through reducing activity in prelimbic NA core-projecting neurons.

An Angiotensin-Responsive Connection from the Lamina Terminalis to the Paraventricular Nucleus of the Hypothalamus Evokes Vasopressin Secretion to Increase Blood Pressure in Mice.

Blood pressure is controlled by endocrine, autonomic, and behavioral responses that maintain blood volume and perfusion pressure at levels optimal for survival. Although it is clear that central angiotensin type 1a receptors (AT1aR; encoded by the Agtr1a gene) influence these processes, the neuronal circuits mediating these effects are incompletely understood. The present studies characterize the structure and function of AT1aR neurons in the lamina terminalis (containing the median preoptic nucleus and organum vasculosum of the lamina terminalis), thereby evaluating their roles in blood pressure control. Using male Agtr1a-Cre mice, neuroanatomical studies reveal that AT1aR neurons in the area are largely glutamatergic and send projections to the paraventricular nucleus of the hypothalamus (PVN) that appear to synapse onto vasopressin-synthesizing neurons. To evaluate the functionality of these lamina terminalis AT1aR neurons, we virally delivered light-sensitive opsins and then optogenetically excited or inhibited the neurons while evaluating cardiovascular parameters or fluid intake. Optogenetic excitation robustly elevated blood pressure, water intake, and sodium intake, while optogenetic inhibition produced the opposite effects. Intriguingly, optogenetic excitation of these AT1aR neurons of the lamina terminalis also resulted in Fos induction in vasopressin neurons within the PVN and supraoptic nucleus. Further, within the PVN, selective optogenetic stimulation of afferents that arise from these lamina terminalis AT1aR neurons induced glutamate release onto magnocellular neurons and was sufficient to increase blood pressure. These cardiovascular effects were attenuated by systemic pretreatment with a vasopressin-1a-receptor antagonist. Collectively, these data indicate that excitation of lamina terminalis AT1aR neurons induces neuroendocrine and behavioral responses that increase blood pressure.SIGNIFICANCE STATEMENT Hypertension is a widespread health problem and risk factor for cardiovascular disease. Although treatments exist, a substantial percentage of patients suffer from "drug-resistant" hypertension, a condition associated with increased activation of brain angiotensin receptors, enhanced sympathetic nervous system activity, and elevated vasopressin levels. The present study highlights a role for angiotensin Type 1a receptor expressing neurons located within the lamina terminalis in regulating endocrine and behavioral responses that are involved in maintaining cardiovascular homeostasis. More specifically, data presented here reveal functional excitatory connections between angiotensin-sensitive neurons in the lamina terminals and vasopressin neurons in the paraventricular nucleus of the hypothalamus, and further indicate that activation of this circuit raises blood pressure. These neurons may be a promising target for antihypertensive therapeutics.

The pronociceptive role of 5-HT6 receptors in ventrolateral orbital cortex in a rat formalin test model.

Recent studies have shown the 5-HT6 receptors are expressed in regions which are important in pain processing such as the cortex, amygdala, thalamus, PAG, spinal cord and dorsal root ganglia (DRG), suggesting a putative role of 5-HT6 receptors in pain modulation. The ventrolateral orbital cortex (VLO) is part of an endogenous analgesic system, consisting of the spinal cord - thalamic nucleus submedius (Sm) - VLO - periaqueductal gray (PAG) - spinal cord loop. The present study assessed the possible role of 5-HT6 receptors in the VLO in formalin-induced inflammatory pain model. Firstly we found that microinjection of selective 5-HT6 receptor agonists EMD-386088 (5 µg in 0.5 µl) and WAY-208466 (8 µg in 0.5 µl) both augmented 5% formalin-induced nociceptive behavior. Microinjection of selective 5-HT6 receptor antagonist SB-258585 (1,2 and 4 µg in 0.5 µl) significantly reduced formalin-induced flinching. Besides, the pronociceptive effects of EMD-386088 and WAY-208466 were dramatically reduced by SB-258585, implicating 5-HT6 receptor mechanisms in mediating these responses. In addition, the pronociceptive effect of EMD-386088 was also prevented by the adenylate cyclase (AC) inhibitor SQ-22536 (2 nmol in 0.5 µl) and the protein kinase A (PKA) inhibitor H89 (10 nmol in 0.5 µl), respectively. We further confirmed the above results with quantification of spinal c-fos expression. Taken together, our results suggested that 5-HT6 receptors play a pronociceptive role in the VLO in the rat formalin test due to its activation of AC - PKA pathway. Therefore, cerebral cortical 5-HT6 receptors could be a new target to develop analgesic drugs.

Effects of the Alpha-1 Antagonist Prazosin on KOR Agonist-Induced Reinstatement of Alcohol Seeking.

BACKGROUND: Stress is associated with relapse to alcohol seeking during abstinence, but the processes underlying this relationship are poorly understood. Noradrenaline is a key transmitter in stress responses and in stress-induced drug seeking. The alpha-1 adrenoceptor antagonist prazosin has been investigated as a treatment for alcoholism and for chronic stress disorders that are frequently comorbid with alcoholism. In rats, we previously showed that prazosin blocks reinstatement of alcohol seeking induced by footshock and yohimbine stressors and reduces yohimbine-induced brain activation. The role of alpha-1 adrenoceptors in reinstatement induced by other stressors is not known. Our most recent work is on the role of kappa opioid receptors in stress-induced reinstatement of alcohol seeking and have reported that the selective kappa opioid receptor agonist U50,488 induces reinstatement and neuronal activation in stress- and relapse-related brain regions. Here we determine the involvement of alpha-1 receptors in reinstatement and brain activation induced by U50,488. METHODS: We trained male Long-Evans rats to self-administer alcohol (12% w/v), extinguished alcohol-reinforced responding, and then determined the effects of prazosin (1 mg/kg) on U50,488 (2.5 mg/kg)-induced reinstatement and regional Fos expression. RESULTS: Prazosin blocked U50,488-induced reinstatement and decreased U50,488-induced Fos expression in the orbitofrontal cortex, nucleus accumbens core, ventral bed nucleus of the stria terminalis, central and basolateral amygdalar nuclei and ventral tegmental area. CONCLUSIONS: These findings suggest that prazosin may reduce U50,488-induced relapse by inhibiting activity in 1 or more of these brain areas.

Antidepressants upregulate c-Fos expression in the lateral entorhinal cortex and hippocampal dorsal subiculum: Study in rats.

Neural circuits involved in the development of depression are currently poorly understood. To provide insight into this issue, we evaluated the influence of seven clinically effective antidepressants on neuronal activity in thirty rat brain areas. Drugs belonging to all major groups of antidepressants (imipramine, reboxetine, fluoxetine, bupropion, mirtazapine, agomelatine, and phenelzine) were examined; since antidepressants typically require weeks of continued administration before they achieve a therapeutic effect, we administered these drugs for 21 days. The experiments were conducted with male Wistar rats. To identify the neuroanatomical targets for antidepressants, the alterations of c-Fos expression in different brain areas were measured using ELISA assay. The drugs were examined at doses sufficient to produce behavioral effect in the rat forced swim test (FST). All the drugs at the behaviorally relevant doses activated two brain areas, the lateral entorhinal cortex and dorsal subiculum of the hippocampus; none of the drugs affected the c-Fos expression in the medial orbital, prelimbic and infralimbic cortex, caudate putamen, nucleus accumbens core, bed nucleus of stria terminalis, hipothalamic paraventricular nucleus, medial amygdaloid nucleus, lateral habenula, substantia nigra pars compacta and pars reticulata, ventral tegmental area, hippocampal ventral subiculum, dorsal and ventral periaqueductal gray matters, and medial entorhinal cortex. These findings suggest that the stimulation of the lateral entorhinal cortex and hippocampal dorsal subiculum play a role in therapeutic effects of antidepressants.

Man-made mineral fiber effects on the expression of anti-oncogenes P53 and P16 and oncogenes C-JUN and C-FOS in the lung tissue of Wistar rats.

Man-made mineral fibers (MMMFs) are substitutes for asbestos. MMMFs are widely used as insulation, but their molecular mechanisms underlying the tumorigenic effects in vivo have been poorly studied. For this reason, this work aimed to explore the properties and carcinogenic molecular mechanisms of MMMFs. The three MMMFs, rock wool (RW), glass fibers (GFs), and ceramic fibers (CFs), were prepared into respirable dust. Particle size, morphology, and chemical composition were analyzed by laser particle analyzer, scanning electron microscope, and X-ray fluorescence spectrometer, respectively. The Wistar rats were administered multiple intratracheal instillations of three MMMFs once a month. Then, several parameters (e.g. body mass, lung mass, and lung histology) were measured at 1, 3, and 6 months. After that, levels of P53, P16, C-JUN, and C-FOS mRNA and protein were measured by quantitative real-time reverse transcription polymerase chain reaction and Western blotting. This work found that exposure to MMMFs could influence the growth of body mass and increase lung mass. General conditions showed white nodules and irregular atrophy. In addition, MMMFs could lead to inactivation of anti-oncogene P16 and activation of proto-oncogenes (C-JUN and C-FOS) in the mRNA and protein levels, in which GF and CF were more obvious compared with RW. The effect of MMMFs was different, which may be related to the physical and chemical characteristics of different MMMFs. In conclusion, MMMFs (GF and CF) could induce an unbalanced expression of cancer-related genes in the lung tissues of rats. The understanding of the determinants of toxicity and carcinogenicity provides a scientific basis for developing and introducing new safer MMMF products, and the present study provides some useful insights into the carcinogenic mechanism of MMMFs.

Exposure to prenatal antidepressant alters medial prefrontal-striatal synchronization in mice.

Citalopram (CTM), a selective serotonin reuptake inhibitor (SSRI), has been widely used to treat panic disorders, such as depression which is one of the most disabling, yet common, psychiatric disorders. Although prenatal antidepressant exposure has a major impact on the neurobehavioral development of the offspring, such as anxiety, depression- and autism-like behaviors, the brain alterations of SSRI influence remained largely unknown. We show here, using electrophysiological recordings, that CTM exposure during the last 7 d of gestation can alter theta- and gamma-band oscillation and synchronization in the corticostriatal loop of 2-3 month-old mouse offspring. The dendritic length and number of dendritic branches in prefrontal neurons of these CTM-exposed mice are significantly reduced, consistent with decreased levels of N-methyl-d-aspartate receptors (NMDARs) and calcium/calmodulin-dependent protein kinase II (CaMKII) in the medial prefrontal cortex (mPFC). In addition, the level of c-Fos in both the mPFC and striatum is significantly increased. Together, these results advance our understanding of a neural network that is potentially responsible for abnormalities induced by prenatal antidepressant exposure.

Curcumae Radix Extract Decreases Mammary Tumor-Derived Lung Metastasis via Suppression of C-C Chemokine Receptor Type 7 Expression.

Curcumae radix is the dry root of Curcuma longa L. (turmeric) that can be used either as a spice or traditional medicine. The aim of this study was to investigate the survival benefits and the anti-metastatic activity of curcumae radix extract (CRE) in MCF7 cells and in MMTV-PyMT transgenic mice-a mouse model of breast cancer metastasis. In vitro wound scratch assay revealed that CRE treatment inhibited cell motility and cell migration in a dose-dependent manner. To investigate the effect of CRE in breast cancer metastasis, MMTV-PyMT transgenic female virgin mice were used and randomly divided into two groups. For survival curve analysis, CRE was administered in a dose of 50 mg/kg to 8⁻20-week-old mice. Interestingly, CRE treatment significantly increased the median and prolonged survival of MMTV-PyMT mice. Furthermore, CRE treatment decreased tumor burden and inhibited cell proliferation in primary breast tumor, and also suppressed mammary tumor-derived lung metastasis. The size of the lung metastases substantially decreased in the CRE-treated group compared with the ones in the control group. Curcumae radix extract showed anti-metastatic activity through regulating the expression of metastasis markers including C-C Chemokine Receptor Type 7, Matrix Metalloproteinase 9 and the proto-oncogenes c-fos and c-jun. We demonstrated that these metastatic regulators were decreased when CCR7 expression was suppressed in MCF7 cells transfected with CCR7 siRNA. The results of this study show that curcumae radix exerts antitumor and anti-metastatic activities, and we suggest that curcumae radix might be a potential supplement for the treatment and prevention of breast cancer metastasis.

Effects of Electroacupuncture on Expression of D1 Receptor (D1R), Phosphorylation of Extracellular-Regulated Protein Kinase 1/2 (p-ERK1/2), and c-Fos in the Insular Cortex of Ketamine-Addicted Rats.

BACKGROUND The aim of this study was to investigate the effects of electroacupuncture (EA) on expression of the D1 receptor (D1R), phosphorylation of extracellular-regulated protein kinase 1/2 (p-ERK1/2) and c-Fos in the insular cortex (IC) of ketamine-addicted rats. MATERIAL AND METHODS Sprague-Dawley rats were randomly divided into 7 groups: the normal group, the normal saline (NS) group, the ketamine (Ket) group, the U0126+Ket group, the SCH23390+Ket group, the Ket+acupoints EA (EA1) group, and the Ket+ non-acupoints EA (EA2) group. We used immunohistochemistry to detect the expression of D1R, p-ERK1/2, and c-Fos. We also used Nissl staining techniques to study the morphology of IC neurons. RESULTS Our study demonstrated that the ketamine group had sparsely distributed neurons, large intracellular vacuoles, nuclei shift, and unclear nucleolus. The number of Nissl-positive (neuronal) cells in the ketamine group were decreased than in the normal group. Our results also indicated that there was significantly lower expression of D1R, p-ERK1/2, and c-Fos in the IC of the U0126+Ket group, SCH23390+Ket group, and Ket+EA1 group as compared with that of the Ket group. CONCLUSIONS Ketamine addiction induces c-Fos overexpression in the IC by increasing the expression of D1R and p-ERK1/2. Acupoints EA downregulate D1R and p-ERK1/2 by reducing the overexpression of c-Fos.

The effects of early exposure to MK-801 during environmental enrichment on spatial memory, methamphetamine self-administration and cue-induced renewal in rats.

OBJECTIVE: Accumulating evidence indicates an association between improved cognition and the early introduction of environmental enrichment (EE). The beneficial effect of EE has also been examined in the field of methamphetamine (METH) dependence. The present study was designed to examine whether early cognitive alterations by dizocilpine (MK-801) in adolescence can impact the effect of EE on spatial memory, METH self-administration (SA), and cue-induced renewal in adulthood. METHODS: In Experiments 1 and 2, Morris Water Maze (MWM) performance, c-Fos expression and N-methyl d-aspartate receptor subtype 2B (NMDAR2B) levels were determined in various brain regions following a change in rearing condition from EE to an isolation environment (IE) at different points (PD 41-60 or PD 51-70). In Experiments 3 and 4, MWM performance and METH SA behaviors in adulthood were tested following adolescent administration of MK-801 during different periods of adolescence (PD 41-60 or PD 51-70) under EE rearing conditions. RESULTS: The early introduction of the IE at PD 41-60 significantly decreased the beneficial effect of EE on MWM performance in adulthood as compared to IE exposure at PD 51-70. Different rearing conditions also altered c-Fos expression and NMDA2B receptor activity in a regionally specific pattern. EE induced structural and systemic changes in the hippocampus that were associated with improvements in spatial memory. Early administration of MK-801 at PD 41-60 and PD 51-70 produced distinctive effects on the behavioral outcomes of METH SA and cue-induced renewal. CONCLUSION: Early cognitive alterations have a profound impact on spatial memory and METH dependence.

α2A-Adrenergic Receptor Activation Decreases Parabrachial Nucleus Excitatory Drive onto BNST CRF Neurons and Reduces Their Activity In Vivo.

Stress contributes to numerous psychiatric disorders. Corticotropin releasing factor (CRF) signaling and CRF neurons in the bed nucleus of the stria terminalis (BNST) drive negative affective behaviors, thus agents that decrease activity of these cells may be of therapeutic interest. Here, we show that acute restraint stress increases cFos expression in CRF neurons in the mouse dorsal BNST, consistent with a role for these neurons in stress-related behaviors. We find that activation of α2A-adrenergic receptors (ARs) by the agonist guanfacine reduced cFos expression in these neurons both in stressed and unstressed conditions. Further, we find that α- and ß-ARs differentially regulate excitatory drive onto these neurons. Pharmacological and channelrhodopsin-assisted mapping experiments suggest that α2A-ARs specifically reduce excitatory drive from parabrachial nucleus (PBN) afferents onto CRF neurons. Given that the α2A-AR is a Gi-linked GPCR, we assessed the impact of activating the Gi-coupled DREADD hM4Di in the PBN on restraint stress regulation of BNST CRF neurons. CNO activation of PBN hM4Di reduced stress-induced Fos in BNST Crh neurons. Further, using Prkcd as an additional marker of BNST neuronal identity, we uncovered a female-specific upregulation of the coexpression of Prkcd/Crh in BNST neurons following stress, which was prevented by ovariectomy. These findings show that stress activates BNST CRF neurons, and that α2A-AR activation suppresses the in vivo activity of these cells, at least in part by suppressing excitatory drive from PBN inputs onto CRF neurons.SIGNIFICANCE STATEMENT Stress is a major variable contributing to mood disorders. Here, we show that stress increases activation of BNST CRF neurons that drive negative affective behavior. We find that the clinically well tolerated α2A-AR agonist guanfacine reduces activity of these cells in vivo, and reduces excitatory PBN inputs onto these cells ex vivo Additionally, we uncover a novel sex-dependent coexpression of Prkcd with Crh in female BNST neurons after stress, an effect abolished by ovariectomy. These results demonstrate input-specific interactions between norepinephrine and CRF, and point to an action by which guanfacine may reduce negative affective responses.

Na+, K+-ATPase inhibition causes hyperactivity and impulsivity in mice via dopamine D2 receptor-mediated mechanism.

Hyperactivity and impulsivity are common symptoms in several psychiatric disorders. Although dysfunction of Na+, K+-ATPase has been reported to be associated with the psychiatric disorders, it is not clear whether inhibition of Na+, K+-ATPase causes behavioral effects, including hyperactivity and impulsivity, in mice. Here, we evaluated the effect of intracerebroventricular (icv) injection of ouabain, an inhibitor of Na+, K+-ATPase, on hyperactivity and impulsivity in mice. At seven days after icv injection, ouabain-injected mice displayed the increase in the distance traveled in the open field arena in the open field test and the increase in the number of head-dipping behavior in the cliff avoidance test. Chlorpromazine or haloperidol, typical antipsychotics, reduced the hyperactivity and impulsivity in ouabain-injected mice. On the other hand, neither lithium carbonate nor valproate, established mood-stabilizing drugs, improved hyperactivity and impulsivity in our mouse model. Furthermore, ouabain-injected mice exhibited the increase in the number of c-fos-positive cells in the nucleus accumbens and the prefrontal cortex but not in the ventral tegmental area, which was reduced by haloperidol. These results suggest that the dysfunction of Na+, K+-ATPase causes hyperactivity and impulsivity via hyperactivation of dopamine D2 receptor-mediated signaling pathway, causing disturbed neuronal circuits in mice.

MiR-7 Mediates the Zearalenone Signaling Pathway Regulating FSH Synthesis and Secretion by Targeting FOS in Female Pigs.

Zearalenone (ZEA) acts as an environmental endocrine disruptor (EED) to cause health detriments. miRNAs were reported to influence the synthesis and secretion of pituitary hormones. However, the interactions between ZEA and miRNAs and related mechanisms remain unclear. The aims of this study were to determine whether and how miR-7 affects animal reproduction by its interactions with ZEA in the pig pituitary, which is sensitive to ZEA and has been used as an important animal model in medical research. Expressions of miRNA were detected by real-time PCR, in situ hybridization, and immunohistochemistry. The effects of ZEA, miR-7, and their interactions in the pituitary gland were identified by using an ovariectomized pig model, transfecting miR-7 mimics and inhibitor, radioimmunoassay, luciferase reporter assay, and Western blotting. The ZEA dosage was 7.5 mg/kg body weight in vivo and 1 µM in vitro. Our results demonstrate miR-7 acts to regulate gonadotropin synthesis and secretion. Furthermore, we found that ZEA leads to reproductive defects by enhancing miR-7 expression, which subsequently inhibits FSH synthesis and secretion. In vitro and in vivo experiments revealed that the effects of ZEA rely on G protein-coupled estrogen receptor 1, and miR-7 functions by mediating ZEA signaling pathway and targeting the Finkel-Biskis-Jinkins murine osteosarcoma viral oncogene homolog (FOS) gene. These findings show that miRNAs are key intrinsic factors regulating pituitary gonadotropins by mediating EED signaling in pituitary glands, and the actions of miRNAs and EEDs should be seriously considered in related studies about medical practice and animal production.