HI Rats Research Articles

HSPB1 overexpression improves hypoxic-ischemic brain damage by attenuating ferroptosis in rats through promoting G6PD expression.

Heat-shock protein B (HSPB1) has a neuroprotective effect on brain injury and is a negative regulator of ferroptosis. Therefore, we infer that HSPB1 plays a protective role in hypoxic-ischemic (HI) brain damage by inhibiting ferroptosis. A neonatal rat model of hypoxic-ischemic (HI) brain damage was established. HSPB1 overexpression plasmid and the negative control were injected into the lateral ventricle of rats 48 h before HI brain damage surgery. HSPB1 and glucose-6-phosphate dehydrogenase (G6PD) levels, infarction rate, iron accumulation, apoptosis, and ferroptosis-related markers were estimated with the assistance of qRT-PCR, 2,3,5-triphenyl tetrazolium chloride (TTC) staining, Prussian blue staining, iron assay kit, TUNEL staining, and Western blot. In vitro, after transfection, HSPB1 and G6PD levels, oxygen-glucose deprivation (OGD)-mediated hippocampal neuron cell viability, apoptosis, iron content, and ferroptosis-related markers were assessed using qRT-PCR, MTT, flow cytometry, iron assay kit, and Western blot. HSPB1 and G6PD were overexpressed in the hippocampus tissues of HI rats. High expression of HSPB1 in HI rats lessened infarction rate and ferritin level, hindered iron accumulation and apoptosis, and promoted GPX4, SLC7A11, and TFR1 levels. In OGD-mediated hippocampal neuron cells, HSPB1 upregulation intensified the viability and repressed apoptosis and ferroptosis, whereas G6PD silencing reversed the effects of HSPB1 upregulation. We documented that HSPB1 overexpression unleashes neuroprotective effects via modulating G6PD expression, which offers a novel target for the prevention and treatment of HI brain damage.NEW & NOTEWORTHY HSPB1 and G6PD were overexpressed in the hippocampus tissues of HI rats. High expression of HSPB1 in HI rats mitigated infarction rate and iron accumulation. HSPB1 overexpression reduced ferritin level, attenuated apoptosis, yet augmented GPX4, SLC7A11, and TFR1 levels in the hippocampus tissues of HI rats. G6PD deletion impaired the protective role of HSPB1 overexpression against HI brain damage-induced ferroptosis.

Overexpression of microRNA-381-3p ameliorates hypoxia/ischemia-induced neuronal damage and microglial inflammation via regulating the C-C chemokine receptor type 2 /nuclear transcription factor-kappa B axis

ABSTRACT microRNAs, as small endogenous RNAs, influence umpteen sophisticated cellular biological functions regarding neurodegenerative and cerebrovascular diseases. Here, we interrogated miR-381-3p’s influence on BV2 activation and neurotoxicity in ischemic and hypoxic environment. Oxygen-glucose deprivation (OGD) was adopted to induce microglial activation and HT-22 neuron damage. Quantitative polymerase chain reaction (qRT-PCR) was taken to check miR-381-3p expression in OGD-elicited BV2 cells and HT-22 neurons. It transpired that miR-381-3p expression was lowered in BV2 cells and HT-22 cells elicited by OGD. miR-381-3p up-regulation remarkably hampered inflammatory mediator expression in BV2 cells induced by OGD and weakened HT22 neuron apoptosis. In vivo, miR-381-3p expression was abated in HI rats’ ischemic lesions, and miR-381-3p up-regulation could ameliorate inflammation and neuron apoptosis in their brain. C-C chemokine receptor type 2 (CCR2) was identified as the downstream target of miR-381-3p, and miR-381-3p suppressed the CCR2/NF-κB pathway to mitigate microglial activation and neurotoxicity. Therefore, we believed that miR-381-3p overexpression exerts anti-inflammation and anti-apoptosis in ischemic brain injury by targeting CCR2

Scutellarin ameliorates neonatal hypoxic-ischemic encephalopathy associated with GAP43-dependent signaling pathway

BackgroundNeonatal hypoxic-ischemic encephalopathy (HIE) refers to the perinatal asphyxia caused by the cerebral hypoxic-ischemic injury. The current study was aimed at investigating the therapeutic efficacy of Scutellarin (Scu) administration on neurological impairments induced by hypoxic-ischemic injury and exploring the underlying mechanisms.MethodsPrimary cortical neurons were cultured and subjected to oxygen–glucose deprivation (OGD), and then treated with Scu administration. The growth status of neurons was observed by immunofluorescence staining of TUJ1 and TUNEL. Besides, the mRNA level of growth-associated protein 43 (GAP43) in OGD neurons with Scu treatment was detected by quantitative real-time polymerase chain reaction (qRT-PCR). To further verify the role of GAP43 in Scu treatment, GAP43 siRNA and knockout were applied in vitro and in vivo. Moreover, behavioral evaluations were performed to elucidate the function of GAP43 in the Scu-ameliorated long-term neurological impairments caused by HI insult. The underlying biological mechanism of Scu treatment was further elucidated via network pharmacological analysis. Finally, the interactive genes with GAP43 were identified by Gene MANIA and further validated by qRT-PCR.ResultsOur data demonstrated that Scu treatment increased the number of neurons and axon growth, and suppressed cell apoptosis in vitro. And the expression of GAP43 was downregulated after OGD, but reversed by Scu administration. Besides, GAP43 silencing aggravated the Scu-ameliorated neuronal death and axonal damage. Meanwhile, GAP43 knockout enlarged brain infarct area and deteriorated the cognitive and motor dysfunctions of HI rats. Further, network pharmacological analysis revealed the drug targets of Scu participated in such biological processes as neuronal death and regulation of neuronal death, and apoptosis-related pathways. GAP43 exhibited close relationship with PTN, JAK2 and STAT3, and GAP43 silencing upregulated the levels of PTN, JAK2 and STAT3.ConclusionsCollectively, our findings revealed Scu treatment attenuated long-term neurological impairments after HI by suppressing neuronal death and enhancing neurite elongation through GAP43-dependent pathway. The crucial role of Scutellarin in neuroprotection provided a novel possible therapeutic agent for the treatment of neonatal HIE.Graphic abstract

LncRNA TCONS_00041002 improves neurological outcomes in neonatal rats with hypoxic-ischemic encephalopathy by inhibiting apoptosis and promoting neuron survival

It has been reported that Neonatal hypoxic-ischemic encephalopathy (HIE) could induce apoptosis in neonates and result in cognitive and sensory impairments, which are associated with poor developmental outcomes. Despite the improvement in neonatology, there is still no clinically effective treatment for HIE presently. Long non-coding RNAs (lncRNAs) play important roles in cellular homeostasis. Nevertheless, their effects in developing rat brains with HI is little known. Here, we established HIE model in neonate rats and explored the expression and function of lncRNAs in HI, and found the expression of 19 lncRNAs was remarkably changed in the brains of HI rats, compared to the sham group. Among them, three lncRNAs (TCONS_00041002, TCONS_00070547, TCONS_00045572) were enriched in the apoptotic process via gene ontology (GO) and pathway analysis, which were selected for the further qRT-PCR verification. Through lentivirus-mediated overexpression of these three lncRNAs, we found that overexpression of TCONS_00041002 attenuated the cell apoptosis, and increased the vitality of neurons after oxygen-glucose deprivation (OGD), therefore reduced the brain infarction and further promoted the neuron survival as well as improved the neurological disorders in the rats subjected to HIE. What's more, ceRNA network prediction and co-expression verification showed that the expression of TCONS_00041002 was positively associated with Foxe1, Pawr and Nfkbiz. Altogether, this study has exhibited that lncRNA TCONS_00041002 participates in the cell apoptosis and neuronal survival of HIE and represents a potential new target for the treatment of HIE.

Optimization of behavioral testing in a long-term rat model of hypoxic ischemic brain injury

BackgroundHypoxic ischemic (HI) brain injury is a significant cause of childhood neurological deficits. Preclinical rodent models are often used to study these deficits; however, no preclinical study has determined which behavioral tests are most appropriate for long-term follow up after neonatal HI. MethodsHI brain injury was induced in postnatal day (PND) 10 rat pups using the Rice-Vannucci method of unilateral carotid artery ligation. Rats underwent long-term behavioral testing to assess motor and cognitive outcomes between PND11-50. Behavioral scores were transformed into Z-scores and combined to create composite behavioral scores. ResultsHI rats showed a significant deficit in three out of eight behavioral tests: negative geotaxis analysis, the cylinder test and the novel object recognition test. These individual test outcomes were transformed into Z-scores and combined to create a composite Z-score. This composite z-score showed that HI rats had a significantly increased behavioral burden over the course of the experiment. ConclusionIn this study we have identified tests that highlight specific cognitive and motor deficits in a rat model of neonatal HI. Due to the high variability in this model of neonatal HI brain injury, significant impairment is not always observed in individual behavioral tests, but by combining outcomes from these individual tests, long-term behavioral burden can be measured.

Inherent Motor Impulsivity Associates with Specific Gene Targets in the Rat Medial Prefrontal Cortex

High impulsivity characterizes a myriad of neuropsychiatric diseases, and identifying targets for neuropharmacological intervention to reduce impulsivity could reveal transdiagnostic treatment strategies. Motor impulsivity (impulsive action) reflects in part the failure of “top-down” executive control by the medial prefrontal cortex (mPFC). The present study profiled the complete set of mRNA molecules expressed from genes (transcriptome) in the mPFC of male, outbred rats stably expressing high (HI) or low (LI) motor impulsivity based upon premature responses in the 1-choice serial reaction time (1-CSRT) task. RNA-sequencing identified expression of 18 genes that was higher in the mPFC of HI vs. LI rats. Functional gene enrichment revealed that biological processes related to calcium homeostasis and G protein-coupled receptor (GPCR) signaling pathways, particularly glutamatergic, were overrepresented in the mPFC of HI vs. LI rats. Transcription factor enrichment identified mothers against decapentaplegic homolog 4 (SMAD4) and RE1 silencing transcription factor (REST) as overrepresented in the mPFC of HI rats relative to LI rats, while in silico analysis predicted a conserved SMAD binding site within the voltage-gated calcium channel subunit alpha1 E (CACNA1E) promoter region. qRT-PCR analyses confirmed that mRNA expression of CACNA1E, as well as expression of leucyl and cystinyl aminopeptidase (LNPEP), were higher in the mPFC of HI vs. LI rats. These outcomes establish a transcriptomic landscape in the mPFC that is related to individual differences in motor impulsivity and propose novel gene targets for future impulsivity research.

Diminished Myoinositol in Ventromedial Prefrontal Cortex Modulates the Endophenotype of Impulsivity.

Maladaptive impulsivity manifests in a variety of disorders, including attention-deficit hyperactivity disorder (ADHD), depression, and substance use disorder. However, the etiological mechanisms of impulsivity remain poorly understood. In the present study, we used in-vivo proton magnetic resonance spectroscopy (1H-MRS) to investigate neurometabolite content in the prefrontal cortex (PFC) and striatum of rats exhibiting low- versus high-impulsive (LI, HI) behavior on a visual attentional task. We validated our 1H-MRS findings using regionally resolved ex-vivo mass spectroscopy, transcriptomics, and site-directed RNA interference in the ventromedial PFC. We report a significant reduction in myoinositol levels in the PFC but not the striatum of HI rats compared with LI rats. Reduced myoinositol content was localized to the infralimbic (IL) cortex, where significant reductions in transcript levels of key proteins involved in the synthesis and recycling of myoinositol (IMPase1) were also present. Knockdown of IMPase1in the IL cortex increased impulsivity in nonimpulsive rats when the demand on inhibitory response control was increased. We conclude that diminished myoinositol levels in ventromedial PFC causally mediate a specific form of impulsivity linked to vulnerability for stimulant addiction in rodents. Myoinositol and related signaling substrates may thus offer novel opportunities for treating neuropsychiatric disorders comorbid with impulsive symptomology.

Potential biomarkers for neuroinflammation and neurodegeneration at short and long term after neonatal hypoxic-ischemic insult in rat

BackgroundHypoxic-ischemic (HI) encephalopathy causes life-long morbidity and premature mortality in term neonates. Therapies in addition to whole-body cooling are under development to treat the neonate at risk for HI encephalopathy, but are not a quickly measured serum inflammatory or neuronal biomarkers to rapidly and accurately identify brain injury in order to follow the efficacy of therapies.MethodsIn order to identify potential biomarkers for early inflammatory and neurodegenerative events after neonatal hypoxia-ischemia, both male and female Wistar rat pups at postnatal day 7 (P7) were used and had their right carotid artery permanently doubly occluded and exposed to 8% oxygen for 90 min. Sensory and cognitive parameters were assessed by open field, rotarod, CatWalk, and Morris water maze (MWM) test. Plasma and CSF biomarkers were investigated on the acute (24 h and 72 h) and chronic phase (4 weeks). Brains were assessed for gene expression analysis by quantitative RT-PCR Array.ResultsWe found a delay of neurological reflex maturation in HI rats. We observed anxiolytic-like baseline behavior in males more than females following HI injury. HI rats held on the rotarod for a shorter time comparing to sham. HI injury impaired spatial learning ability on MWM test. The CatWalk assessment demonstrated a long-term deficit in gait parameters related to the hind paw. Proinflammatory biomarkers such as IL-6 in plasma and CCL2 and TNF-α in CSF showed an upregulation at 24 h after HI while other cytokines, such as IL-17A and CCL5, were upregulated after 72 h in CSF. At 24 h post-injury, we observed an increase of Edn1, Hif1-α, and Mmp9 mRNA levels in the ipsilateral vs the contralateral hemisphere of HI rats. An upregulation of genes involved with clotting and hematopoietic processes was observed 72 h post-injury.ConclusionsOur work showed that, in the immature brain, the HI injury induced an early increased production of several proinflammatory mediators detectable in plasma and CSF, followed by tissue damage in the hypoxic hemisphere and short-term as well as long-lasting neurobehavioral deficits.

Profile of cortical N-methyl-D-aspartate receptor subunit expression associates with inherent motor impulsivity in rats

Impulsivity is a multifaceted behavioral manifestation with implications in several neuropsychiatric disorders. Glutamate neurotransmission through the N-methyl-D-aspartate receptors (NMDARs) in the medial prefrontal cortex (mPFC), an important brain region in decision-making and goal-directed behaviors, plays a key role in motor impulsivity. We discovered that inherent motor impulsivity predicted responsiveness to D-cycloserine (DCS), a partial NMDAR agonist, which prompted the hypothesis that inherent motor impulsivity is associated with the pattern of expression of cortical NMDAR subunits (GluN1, GluN2A, GluN2B), specifically the protein levels and synaptosomal trafficking of the NMDAR subunits. Outbred male Sprague-Dawley rats were identified as high (HI) or low (LI) impulsive using the one-choice serial reaction time task. Following phenotypic identification, mPFC synaptosomal protein was extracted from HI and LI rats to assess the expression pattern of the NMDAR subunits. Synaptosomal trafficking and stabilization for the GluN2 subunits were investigated by co-immunoprecipitation for postsynaptic density 95 (PSD95) and synapse associated protein 102 (SAP102). HI rats had lower mPFC GluN1 and GluN2A, but higher GluN2B and pGluN2B synaptosomal protein expression versus LI rats. Further, higher GluN2B:PSD95 and GluN2B:SAP102 protein:protein interactions were detected in HI versus LI rats. Thus, the mPFC NMDAR subunit expression pattern and/or synaptosomal trafficking associates with high inherent motor impulsivity. Increased understanding of the complex regulation of NMDAR balance within the mPFC as it relates to inherent motor impulsivity may lead to a better understanding of risk factors for impulse-control disorders.

Top-down control of the medial orbitofrontal cortex to nucleus accumbens core pathway in decisional impulsivity.

Decisional impulsivity is one of the risk factors for occurrence and development of many mental disorders, and that the dysfunctions of orbitofrontal cortex (OFC) and nucleus accumbens core (NAcC) are at least involved. Although previous studies have shown that the role of OFC as a whole in regulating decision-making impulse behavior is inconsistent, it's still unclear that the roles of the subregions of OFC including their projections to the NAcC in decisional impulsivity. The present study was designed to investigate the roles of OFC subregions, medial OFC (mOFC) and lateral OFC (lOFC) and their projections to the NAcC in decisional impulsivity in free-moving rats. We found that rats with low level of decisional impulsivity (LI) showed higher neuronal activity in both the mOFC and lOFC, and more neurons in mOFC but not lOFC projecting to the NAcC were activated, compared with high level of decisional impulsivity (HI) rats. The mOFC-NAcC projections of LI rats showed stronger information communication in beta and low gamma oscillations in the expected reward choice and delay time windows. Further, specific activation (in HI rats) or inhibition (in LI rats) of the mOFC-NAcC pathway could partly reverse their decisional impulsive behaviors. The findings first demonstrated that the mOFC-NAcC pathway was more important than the lOFC-NAcC pathway to the top-down control in decisional impulsivity, which could be a new neural physiological mechanism for psychiatric disorders associated with decisional impulsivity.

Convergent neural connectivity in motor impulsivity and high-fat food binge-like eating in male Sprague-Dawley rats.

Food intake is essential for survival, but maladaptive patterns of intake, possibly encoded by a preexisting vulnerability coupled with the influence of environmental variables, can modify the reward value of food. Impulsivity, a predisposition toward rapid unplanned reactions to stimuli, is one of the multifaceted determinants underlying the etiology of dysregulated eating and its evolving pathogenesis. The medial prefrontal cortex (mPFC) is a major neural director of reward-driven behavior and impulsivity. Compromised signaling between the mPFC and nucleus accumbens shell (NAcSh) is thought to underlie the cognitive inability to withhold prepotent responses (motor impulsivity) and binge intake of high-fat food (HFF) seen in binge eating disorder. To explore the relationship between motor impulsivity and binge-like eating in rodents, we identified high (HI) and low impulsive (LI) rats in the 1-choice serial reaction time task and employed a rat model of binge-like eating behavior. HFF binge rats consumed significantly greater calories relative to control rats maintained on continual access to standard food or HFF. HI rats repeatedly exhibited significantly higher bingeing on HFF vs. LI rats. Next, we employed dual viral vector chemogenetic technology which allows for the targeted and isolated modulation of ventral mPFC (vmPFC) neurons that project to the NAcSh. Chemogenetic activation of the vmPFC to NAcSh pathway significantly suppressed motor impulsivity and binge-like intake for high-fat food. Thus, inherent motor impulsivity and binge-like eating are linked and the vmPFC to NAcSh pathway serves as a 'brake' over both behaviors.

Tissue-specific changes in Srebf1 and Srebf2 expression and DNA methylation with perinatal phthalate exposure.

Perinatal exposure to endocrine disrupting chemicals negatively impacts health, but the mechanism by which such toxicants damage long-term reproductive and metabolic function is unknown. Lipid metabolism plays a pivotal role in steroid hormone synthesis as well as energy utilization and storage; thus, aberrant lipid regulation may contribute to phthalate-driven health impairments. In order to test this hypothesis, we specifically examined epigenetic disruptions in lipid metabolism pathways after perinatal phthalate exposure. During gestation and lactation, pregnant Long–Evans rat dams were fed environmentally relevant doses of phthalate mixture: 0 (CON), 200 (LO), or 1000 (HI) µg/kg body weight/day. On PND90, male offspring in the LO and HI groups had higher body weights than CON rats. Gene expression of lipid metabolism pathways was altered in testis and adipose tissue of males exposed to the HI phthalate dosage. Specifically, Srebf1 was downregulated in testis and Srebf2 was upregulated in adipose tissue. In testis of HI rats, DNA methylation was increased at two loci and reduced at one other site surrounding Srebf1 transcription start site. In adipose tissue of HI rats, we observed increased DNA methylation at one region within the first intron of Srebf2. Computational analysis revealed several potential transcriptional regulator binding sites, suggesting functional relevance of the identified differentially methylated CpGs. Overall, we show that perinatal phthalate exposure affects lipid metabolism gene expression in a tissue-specific manner possibly through altering DNA methylation of Srebf1 and Srebf2.

Recombinant human erythropoietin offers neuroprotection through inducing endogenous erythropoietin receptor and neuroglobin in a neonatal rat model of periventricular white matter damage

Recombinant human erythropoietin (rh-EPO) has been reported to have protective effects against brain injury. The purpose of this study was to evaluate the levels of erythropoietin receptor (EPOR) and neuroglobin (Ngb) in a neonatal rat model of periventricular white matter damage (PWMD), and to identify the relationship between the two proteins. On postnatal day 3 (P3), rats underwent permanent ligation of the right common carotid artery followed by 6% O2 for 4h (HI) or sham operation and normoxic exposure (sham). Immediately after HI, rats received a single intraperitoneal injection of rh-EPO (5U/g) or saline. We assessed the expression level of Ngb and EPOR on postnatal days 5, 7, 10 and 14. EPOR in the HI rats was initially increased as compared to the sham rats at P5. Subsequently, EPOR expression decreased, but was maintained at a higher level than in sham rats from P7 to P14. In rh-EPO treated rats, the increase in EPOR was greater than in HI rats at P5. However, EPOR levels decreased sharply from P7 to P14. In HI rats, Ngb was increased compared to the sham rats from P5 to P14. Ngb levels were further upregulated after rh-EPO administration from P5 to P10 compared to HI rats. However, this upregulation decreased at P14. In conclusion, this study shows that EPOR and Ngb were upregulated, and both of them act as important coordinated neuroprotectors in rh-EPO treatment of PWMD. However, the two proteins exhibit different expression patterns.

Deep Brain Stimulation of the Nucleus Accumbens Core Affects Trait Impulsivity in a Baseline-Dependent Manner.

Deep brain stimulation (DBS) of the nucleus accumbens (NA) is explored as a treatment for refractory psychiatric disorders, such as obsessive-compulsive disorder (OCD), depressive disorder (MDD), and substance use disorder (SUD). A common feature of some of these disorders is pathological impulsivity. Here, the effects of NAcore DBS on impulsive choice and impulsive action, two distinct forms of impulsive behavior, were investigated in translational animal tasks, the delayed reward task (DRT) and five-choice serial reaction time task (5-CSRTT), respectively. In both tasks, the effects of NAcore DBS were negatively correlated with baseline impulsive behavior, with more pronounced effects in the 5-CSRTT. To further examine the effects of DBS on trait impulsive action, rats were screened for high (HI) and low (LI) impulsive responding in the 5-CSRTT. NAcore DBS decreased impulsive, premature responding in HI rats under conventional conditions. However, upon challenged conditions to increase impulsive responding, NAcore DBS did not alter impulsivity. These results strongly suggest a baseline-dependent effect of DBS on impulsivity, which is in line with clinical observations.

Differential effects of co-administration of oxotremorine with SCH 23390 on impulsive choice in high-impulsive rats and low-impulsive rats

The effect of acetylcholine on impulsive choice is thought to be due to interactions between cholinergic and dopaminergic systems, but this hypothesis has not been proven. This study investigated whether D1-like receptors were involved in the effects of the muscarinic cholinergic agonist oxotremorine on impulsive choice in high-impulsive rats (HI rats, n=8) and low-impulsive rats (LI rats, n=8) characterized by basal levels of impulsive choice in a delay-discounting task. The results revealed that oxotremorine (0.05mg/kg) significantly increased the choice of the large reinforcer in HI rats, whereas decreased the choice of the large reinforcer in LI rats. The D1-like antagonist SCH 23390 produced significant reductions in the large-reinforcer choice in HI rats (0.01mg/kg) and LI rats (0.005, 0.0075, and 0.01mg/kg). SCH 23390 significantly inhibited the increase in the choice of the large reinforcer induced by oxotremorine (0.05mg/kg) in HI rats at doses of 0.005 and 0.0075mg/kg, but enhanced the effect of oxotremorine in LI rats only at the dose of 0.0075mg/kg. These findings suggested that D1-like receptors might be involved in the differential effects of oxotremorine on impulsive choice between HI rats and LI rats.

Disruption of cortical N-methyl-d-aspartate receptor tone governs impulsive action

Disruption of cortical N-methyl-d-aspartate receptor tone governs impulsive action

The perceived stigma of substance abuse scale: Reliability and validity with substance using people living with HIV

Drug and Alcohol Dependence 156 (2015) e183–e245 e215 The perceived stigma of substance abuse scale: Reliability and validity with substance using people living with HIV Kristi Stringer1,∗, Joseph E. Schumacher2, Janet M. Turan3, Michael Mugavero4, Mirjam C. Kempf5, Elizabeth Baker1 1 Sociology, University Of Alabama at Birmingham, Hoover, AL, United States 2 Dept of Medicine/Div of Preventive Medicine, University of Alabama at Birmingham, Birmingham, AL, United States 3 Health Care Organization and Policy, University of Alabama at Birmingham, Birmingham, AL, United States 4 School of Medicine/Div. of Infectious Diseases, University of Alabama at Birmingham, Birmingham, AL, United States 5 UAB School of Nursing/Center for Nursing Research, University of Alabama at Birmingham, Birmingham, AL, United States Aims: Substance use (SU) stigma may be especially deleterious forpeople livingwithHIV (PLHIV), impactingbothSUandHIV treatment. To date, tools to assess SU stigma are limited to use with people in treatment programs, & no tool has been validated for use in PLHIV. This study examines the reliability & validity of the PSAS for use with PLHIV who are current users. Methods: The PSASwas administered to154 PLHIVwho are current substance users and who attend a University outpatient HIV clinic for care. Data was examined for internal & reliabilty. Results: The mean of the PSAS was 20.89 (SD=4.24) (range: 08–32, higher scores equals greater levels of perceived stigma). Confirmatory analysis indicate that a one-factor solution fits, with an eigenvalue of 3.06, explaining 38.27% of the variance. Reliability coefficients, including Cronbach’s alpha (〈=0.734), Guttman splithalf (0.706), and item–total correlations indicate adequate internal reliability. Convergent validity was demonstrated through correlations with the fear of enacted SU stigma scale (r= .399, p< .000), the SU Stigma Avoidance Scale (r= .328, p< .000), & the internalized HIV-related stigma scale (r= .195, p< .05). To assess divergent validity, perceived SA stigma was not significantly correlated with measures of the number of close friends a person reports having (r=−.055] or close relatives a person reports having (r=−.055). Conclusions: The PSAS scale is a reliable and valid instrument for use with current users living with HIV. Financial Support: Research reported was supported by NIDA/NIH (Award Number F31DA037106). The content is the responsibility of the authors and does not represent the official views of the NIH. http://dx.doi.org/10.1016/j.drugalcdep.2015.07.579 The role of serotonin 2A (5-HT2A) and 2C (5-HT2C) receptors in the association between BINGE eating and impulsive action Sonja J. Stutz1,∗, Noelle C. Anastasio1,2, Kathryn A. Cunningham1,2 1 Center for Addiction Research, University of Texas Medical Branch, Galveston, TX, United States 2 Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, United States Aims: Binge eating disorder (BED) is the most prevalent eating disorder in the U.S., and is linked to severe obesity and psychological and medical morbidity. Impulsive action is a key factor underlying the etiology and evolving pathogenesis of BED. We hypothesize that impulsive action and binge eating are mechanistically-linked to disrupted serotonin (5-HT) signaling through 5-HT2AR and 5-HT2CR in brain regions, particularly the medial prefrontal cortex (mPFC), that drive the incentivemotivational salience of food and cues that predict food. Methods: Rats were identified as high (HI) or low (LI) impulsive actionphenotypes in the 1-choice serial reaction time (1-CSRT) task. Binge eating in HI vs. LI (n=12/group) was assessed upon 2-hr access to high-fat chow. HI and LI were subjected to a self-administration/forced abstinence paradigm to assess the reinforcing and motivational efficacy of high-fat pellets and associated cues. The mPFC 5-HT2AR and 5-HT2CR protein expression profiles were identified in HI vs. LI rats. Results: HI consumed significantly more kcal during the 2-hr binge vs. LI (p<0.05). The reinforcing efficacy of high-fat pellets was identical in HI and LI. HI exhibited a higher breakpoint for high-fat pellets and higher cue reactivity vs. LI (p<0.05). A positive correlation between premature responses and the ratio of 5-HT2AR:5-HT2CR protein expression in the mPFC (r=0.558, p<0.01) was observed. Conclusions: These data suggest that the level of inherent impulsive action is a determinant of the magnitude of binge eating high-fat chow. We propose that high-fat food is more “wanted” by HI vs. LI, making impulsive responding and binge intake more difficult to withhold in HI. Further, these data support the hypothesis that inherent impulsive actionandbingeeating coalesce at the level of imbalanced 5-HT2AR:5-HT2CR homeostasis within the mPFC. Financial Support: Klarman Family Foundation for Eating Disorders, K99 DA033374 (NCA), K05 DA020087 (KAC). http://dx.doi.org/10.1016/j.drugalcdep.2015.07.580 Comorbidity and functioning of substance-dependent women with sexual abuse history in the stage II women’s recovery group therapy trial Dawn E. Sugarman1,2,∗, Brittany Iles2, Shelly F. Greenfield1,2 1 Harvard Medical School/McLean Hospital, Belmont, MA, United States 2 Division of Alcohol and Drug Abuse; Division of Women’s Mental Health, McLean Hospital, Belmont,

High levels of impulsivity in rats are not accompanied by sensorimotor gating deficits and locomotor hyperactivity

High levels of impulsivity have been linked to a number of psychiatric disorders, including attention-deficit/hyperactivity disorder, drug abuse and schizophrenia. Additionally, schizophrenia patients commonly show deficits in another rather preattentive form of response inhibition, called sensorimotor gating. Given that higher-order functions, such as impulse control, are protected by early and preattentive processes, disturbed gating mechanisms may hamper more complex cognitive-executive functions. In the present study, we therefore tested whether high levels of impulsivity are accompanied by impaired sensorimotor gating in rats. High (HI) and low impulsive (LI) rats were identified based on the number of premature responses in the 5-choice serial reaction time task. Here, LI rats showed higher numbers of omission errors which may suggest attentional deficits while HI rats completed significantly less trials which could indicate a decrease in motivation. However, HI and LI rats did not differ in terms of impulsive decision-making in a delay-based decision-making T-maze task, prepulse inhibition of the acoustic startle response (a measure of sensorimotor gating mechanisms) or locomotor activity levels. Overall, our data indicate that high motor impulsivity is not a suitable predictor of deficient sensorimotor gating and is further not necessarily associated with attentional deficits and/or locomotor hyperactivity in rats.

Dissociation in the Effects of Induced Neonatal Hypoxia-Ischemia on Rapid Auditory Processing and Spatial Working Memory in Male Rats

Infants born prematurely are at risk for cardiovascular events causing hypoxia-ischemia (HI; reduced blood and oxygen to the brain). HI in turn can cause neuropathology, though patterns of damage are sometimes diffuse and often highly variable (with clinical heterogeneity further magnified by rapid development). As a result, though HI injury is associated with long-term behavioral and cognitive impairments in general, pathology indices for specific infants can provide only limited insight into individual prognosis. The current paper addresses this important clinical issue using a rat model that simulates unilateral HI in a late preterm infant coupled with long-term behavioral evaluation in two processing domains - auditory discrimination and spatial learning/memory. We examined the following: (1) whether deficits on one task would predict deficits on the other (suggesting that subjects with more severe injury perform worse across all cognitive domains) or (2) whether domain-specific outcomes among HI-injured subjects would be uncorrelated (suggesting differential damage to orthogonal neural systems). All animals (sham and HI) received initial auditory testing and were assigned to additional auditory testing (group A) or spatial maze testing (group B). This allowed within-task (group A) and between-task (group B) correlation. Anatomic measures of cortical, hippocampal and ventricular volume (indexing HI damage) were also obtained and correlated against behavioral measures. Results showed that auditory discrimination in the juvenile period was not correlated with spatial working memory in adulthood (group B) in either sham or HI rats. Conversely, early auditory processing performance for group A HI animals significantly predicted auditory deficits in adulthood (p = 0.05; no correlation in shams). Anatomic data also revealed significant relationships between the volumes of different brain areas within both HI and shams, but anatomic measures did not correlate with any behavioral measure in the HI group (though we saw a hippocampal/spatial correlation in shams, in the expected direction). Overall, current data provide an impetus to enhance tools for characterizing individual HI-related pathology in neonates, which could provide more accurate individual prognoses within specific cognitive/behavioral domains and thus improved patient-specific early interventions.

Characterization of neonatal seizures in an animal model of hypoxic-ischemic encephalopathy.

In this study, we use time-locked video and electroencephalography (EEG) recordings to characterize acute seizures and EEG abnormalities in an animal model that replicates many salient features of human neonatal hypoxic-ischemic encephalopathy (HIE) including the brain injury pattern and long-term neurologic outcome. Hypoxia-ischemia (HI) was induced in 7-day-old rats by ligating the right carotid artery and exposing the pups to hypoxia for 2 h (Rice-Vannucci method). To identify seizures and abnormal EEG activity, pups were monitored by video-EEG during hypoxia and at various time points after HI. Occurrence of electroclinical seizures, purely electrographic seizures and other abnormal discharges on EEG, was quantified manually. A power spectrum analysis was done to evaluate the effects of HI on EEG spectra in the 1-50 Hz frequency band. During hypoxia, all pups exhibit short duration, but frequent electroclinical seizures. Almost all pups continue to have seizures in the immediate period following termination of hypoxia. In more than half of the HI rats, seizures persisted for 24 h; for some of them, the seizures continued for >48 h. Seizures were not observed in any rats at 72 h after HI induction. A significant reduction in background EEG voltage in the cortex ipsilateral to the ligated carotid artery occurred in rats subjected to HI. In addition, purely electrographic seizures, spikes, sharp waves, and brief runs of epileptiform discharges (BREDs) were also observed in these rats. HI induction in P7 rats using the Rice-Vannucci method resulted in the development of seizures and EEG abnormalities similar to that seen in human neonates with HIE. Therefore, we conclude that this is a valid model to test the efficacy of novel interventions to treat neonatal seizures.