News & Events
International Society for Developmental Psychobiology (ISDP)
November 12-14, 2014
Society for Neuroscience (SfN)
November 15-19, 2014
Click images to see larger image
- Pilot 1: Effect of prenatal ethanol exposure on extracellular matrix.
- Pilot 2: Determination of Sensitive Periods for PCB Effects on Voluntary Ethanol Consumption.
- Pilot 3: The role of the amygdala in ethanol-affected social behavior
- Pilot 4: Kappa opioids during ontogeny and ethanol reinforcement
- Pilot 5: The role of Protein Kinase C in adolescent ethanol-related effects.
- Pilot 6: Pilot 6: Investigations into the role of neurosteroid and glutamate interactions in persistent neurobehavioral dysfunction associated with early adolescent alcohol exposure
- Pilot 7: Interplay between prenatal alcohol exposure and postnatal alcohol re-exposure
- Pilot 8: Alcohol-induced forebrain damage: Does the neural sequelae of alcoholism differ depending on the pattern of drinking or age of onset?
PI: Russell Matthews (link to e-mail: MatthewR@upstate.edu)
Our studies provided compelling evidence that the neural extracellular matrix is altered by prenatal exposure to ethanol. In particular we noted a reduction in the formation of an important extracellular matrix structure called the perineuronal net (PNN). The structure of PNNs and their net-like appearance is due to the fact that this structure covers the surface of cells and proximal neurites but is excluded from sites of synaptic contact. PNNs form during a preadolescent to adolescent period during brain development around a subset of neurons and their formation is known to depend on appropriate activity during this early critical period. Importantly the reduction in the number of cells with PNNs with fetal alcohol exposure suggests a developmental delay that leads to permanent alteration in the synaptic plasticity and stability mediated by changes in the neural matrix. Interestingly, however, while one component of PNN structures, aggrecan, was specifically altered with ethanol exposure, the overall levels of aggrecan protein or mRNA were not significantly altered. This is a hitherto unappreciated level of complexity in the formation and structure of PNNs and/or binding and processing of aggrecan. These findings led us to change the direction of our work towards understanding the molecular and biochemical basis of PNNs in order to understand and explain these findings. We believe ongoing work in our lab will have an important impact on our understanding of ethanol effects on the neural matrix and developmental plasticity, and that the value of these findings will extend into other areas of the neurological impact of substance abuse and perhaps into neuropsychiatric disorders.
PI: David Berger (link to e-mail: firstname.lastname@example.org)
Research Questions: Will exposure to polychlorinated biphenyls (PCBs) either only during gestation or only while nursing, versus exposure during both developmental periods (perinatal) differentially affect the volitional intake of ethanol in adolescent male and female Sprague-Dawley (SD) rats, compared to unexposed controls? Methods: We used two groups of pregnant dams to produce the male and female offspring in which voluntary intake of ethanol was measured. From gestational days 5 to 19, in addition to their Mazuri Rodent Pellets, the PCB-exposed dams were fed half a Nilla Wafer cookie onto which 0.1 ml of corn oil containing 4.0 µg/g (body weight) of a 1:1 mixture of PCB Aroclor 1254:1260 was placed. During the corresponding days, the wafers fed to the control dams contained 0.1 ml of corn oil alone. A fostering or cross fostering procedure was used to create the desired exposure conditions for the offspring. We used a limited-access procedure to provide each rat with access to ethanol and measured how much they consumed using several approaches: Continuous access (24 hr): The mean amounts of 2%, 4%, & 6% ethanol (g/kg) consumed by each female and male offspring in each of the four groups were used to compute a three-way mixed ANOVA (sex x groups x solutions). Only the main effect of solutions was significant. The offspring drank more 4% than both 2% and 6% ethanol, and more 4% than 2%, solutions. Limited access (1 hr): The mean amounts of ethanol consumed by each animal were used to compute a two-way ANOVA (sex x groups). Only the main effect of sex was significant. The females drank more than the males. 1-hr water intake: The corresponding amounts of water (from the second bottle) consumed by each animal during the same period after ethanol intake had stabilized were used to compute a similar two-way ANOVA as above. Again, only the main effect of sex was significant, with females consuming more water than males. These results did not agree with previous findings that only females exposed perinatally to PCBs showed increased ethanol consumption compared to unexposed females and males. The latter three groups did not differ.
PI: Sandra Mooney (link to e-mail: email@example.com)
Pregnant Long-Evans rats were injected with ethanol (i.p., 2.9 g/kg as a 20% v/v solution) or saline on gestational day (G) 7 (gastrulation), G12 (early neuronal generation) or G15 (mid neuronal generation). In this model, peak blood ethanol concentrations reached ~300 mg/dl. Dams were allowed to birth and raise their own litter. No effects were seen on litter outcome; number of pups, average pup weight, or male: female ratio. A modified social interaction test was used to assess four aspects of social behavior (social investigation, play fighting, contact behavior, and social motivation) and locomotor activity. Males and females underwent testing on postnatal day (P)28, P42, or P75; early adolescence, late adolescence, or adulthood, respectively. Exposures at the different times resulted in behavioral outcomes that were age-, sex-, and treatment-specific. We also completed and published a study examining the effects of acute prenatal exposure to ethanol and social enrichment during adolescence. Social behavior was tested and gene expression in the ventral striatum and amygdala was examined. Housing conditions altered behavior AND altered gene expression of specific sets of genes involved in synaptic plasticity and neural activity. In a follow-up to the above study, micro-RNA expression was also examined in the same treatment groups and found to have significant differences among ethanol treatment and housing. A western blot study examining the developmental timeline of changes in expression of g-aminobutyric acid (GABA) receptor subunits in the CeA is underway.
PI: Michael Nizhnikov (link to e-mail: firstname.lastname@example.org)
The main aim of the pilot project was to investigate the effects of low levels of prenatal ethanol exposure on future intake of and reinforcement to ethanol. Additionally the effects of prenatal ethanol on changes in kappa opioid mediation of ethanol drinking and reinforcement were investigated. Initially age differences in ethanol responding were investigated. Results indicated that 4-day old rat pups (P4) were more sensitive to the appetitive and less sensitive to the aversive properties of ethanol than their 12-day old (P12) counterparts (Nizhnikov et al., 2012). Following this set of experiments, kappa opioid mediation of this effect was investigated. While administration of a kappa opioid antagonist prior to conditioning blocked the appetitive properties of ethanol in P4 pups, the same antagonist actually increased the appetitive reinforcing properties of ethanol in P12 subjects (Pautassi et al., 2012). Following these data we exposed infant rats to ethanol (1 g/kg) through intragastric intubation on P1–P4. Rat pups were then tested on P12 for changes in ethanol's reinforcing properties due to earlier exposure. Rat pups exposed to alcohol found low doses (0.25 g/kg) of ethanol appetitive while controls showed no effect, clearly indicating changes in ethanol's appetitive properties following early exposure to the drug. The final stage of the project looked at the effects of prenatal ethanol exposure on responding to alcohol and kappa involvement later in life. Our first experiment tested the motivational valance of the kappa opioid system across age. We used a specific kappa agonist (U62,066) at two different ages (P4 and P12) as an unconditioned stimulus in a CTA model. The results clearly showed that younger subjects increased intake of a flavor associated with kappa opioid stimulation while older subjects decreased its intake demonstrating an ontogenetic shift in the motivational valance of the kappa system. Our next step was to test the motivational valance of kappa at P12 following prenatal ethanol exposure. Results indicated that while control subjects found kappa agonist extremely aversive, subjects prenatally treated with ethanol found it appetitive. This indicates a major shift in the motivational valance of the system following prenatal exposure. We then tested kappa mediation of ethanol intake following prenatal ethanol exposure (1 g/kg). Kappa antagonists increased the intake of ethanol in control subjects but had no effect on pups which experienced ethanol prenatally. Overall the results indicate a major change in the function of the kappa opioid system and its mediation of ethanol drinking and reinforcement following low levels of prenatal ethanol exposure. Future studies are on going and an RO1 building on these results is currently under review.
PI: David F. Werner (link to e-mail: email@example.com)
In the first fiscal year, pilot project 5 made substantial progress on all aims and expanded on specific experiments. Protein Kinase C (PKC) isoforms were characterized during adolescent ontogeny in both cortical whole cell samples as well as in synaptosomal preparations. Results indicate that PKC isoforms display bidirectional changes in expression and cellular localization. Notably, following ethanol exposure, novel PKC isoforms are reduced during adolescence whereas no effects were seen in adults. Studies also noted that differential effects are also present for PKA following ethanol exposure. Specifically, unlike adults, PKA regulatory subunits were not increased in adolescents. Aside from differential adolescent regulation of protein kinases following ethanol exposure, behaviorally, decreasing PKC activity caused adolescents to have greater ethanol sedative/hypnotic sensitivity, whereas increasing PKC activity increased ethanol resistance in adults. Given the pattern of adolescent ontogeny, coupled with ethanol-induced adaptations on the novel PKC pathway, we further investigated whether the phospholipase A2 (PLA2)/arachidonic acid pathway was involved. Indeed, following inhibition of arachidonic acid production via PLA2 substantially increased adolescent sedative/hypnotic sensitivity without altering adult sensitivity. Although these experiments were not included in the original proposal, they significantly increase the impact of the overall study by giving more focus to a specific intracellular pathway. Lastly, experiments have begun assessing GABA-A receptor expression during adolescents. Although preliminary, studies indicate that GABA-A receptor subunits associated with synaptic receptors have yet to reach adult levels. Further experiments are necessary to fully understand GABA-A receptor subunit composition and synaptic localization and will be completed soon.
Pilot 6: Investigations into the role of neurosteroid and glutamate interactions in persistent neurobehavioral dysfunction associated with early adolescent alcohol exposure
PI: Jilla Sabeti
This pilot explores the role of neurosteroid factors as critical mediators of the unique effects of adolescent alcohol exposure on hippocampal long-term potentiation (LTP) formation and related learning behaviors. As a new investigator, work undertaken by Dr. Sabeti in the first funding period beginning Sept 2011 focused on launching a chronic alcohol exposure paradigm in early-stage adolescent rats, which involved chronic intermittent ethanol vapor exposure and new behavioral studies proposed for Aim 1. Efforts were also directed towards the harvesting of brain tissue for biochemical analyses at various time points of withdrawal from the chronic ethanol treatments (24 hr – 21 days). Methodology for vapor exposure in new ethanol vapor chambers was optimized, resulting in target BECs of 250 -300 mg/dL over the chronic 12 day exposure period (14 hr on, 10 hr off, daily), based on a schedule shown to consistently elicit robust activation of a unique synaptic LTP signature in hippocampus after acute ethanol withdrawal in early-adolescent male rats (Sabeti, 2011). Behavioral phenotyping was initiated during different withdrawal times involving two new behavioral assays that were developed (e.g., conditioned escape task and place and object recognition task) to measure effects of finasteride administration in reversing some of the long-term consequences of adolescent ethanol exposure on hippocampal neurobehavioral functioning. More recently, after the move to a new animal facility, Dr. Sabeti has set up a brain slice electrophysiology recording system in her new lab space to enable execution of the brain slice experiments for Aims 2 and 3 during the remaining funding period.
PI: Aesoon Park (link to e-mail: firstname.lastname@example.org)
Gestation and adolescence are the highest risk periods for alcohol exposure in humans. Because of critical brain development occurring during these periods, the risks associated with alcohol exposure during these periods are devastating to diverse functioning domains. However, human prospective studies rarely have connected these two lines of literature. This study aims to characterize how alcohol exposures during these two developmental periods combine to affect the trajectories of alcohol and psychosocial functioning throughout adolescence. This project is designed to test the DEARC's overarching theme of the "alcoholism generator" in humans, via testing developmental effects caused by alcohol exposures during the critical developmental stages of gestation and adolescence. This human study will complement existing main projects of the DEARC that use animal models, highlighting parallelism in terms of augmenting effects of prenatal and post-natal alcohol exposure.
Pilot 8: Alcohol-induced forebrain damage: Does the neural sequelae of alcoholism differ depending on the pattern of drinking or age of onset?
PI: Dr. Lisa Savage (link to e-mail: email@example.com)
The goal of this proposal is to determine the neurotrophin, cellular and behavioral disruptions that different ethanol-exposure patterns (repeated ethanol binge vs. long-term chronic exposure) produced in the brains of both adolescent and adult rats. Specifically, adolescent (35-day-old) and young adult (75-day-old) rats will be assigned to 'control' or to one of two different ethanol-exposure patterns (binge vs. chronic). Neurotrophin signaling (Brain Derived Neurotrophin Factor [BDNF]; Nerve Growth Factor [NGF]) and forebrain cholinergic cell populations, which are especially sensitive to neurotrophin loss and both binge and chronic alcohol-induced toxicity, will be assessed at the end of ethanol treatment and at different post-abstinence periods to map brain damage and recovery. The brain areas assessed will be the alcohol-sensitive regions of the hippocampus, frontal cortex, medial septum and nucleus basalis magnocellularis.