Exposure to prenatal infections has been widely associated with the increased risk for neuropsychiatric disorders of developmental origin such as schizophrenia and autism. Although several behavioral and cognitive deficits have been detected during adulthood in rodent models of prenatal infections, early behavioral changes have not been well characterized. In a prenatal lipopolysaccharide (LPS) model, we have previously observed significant alterations in the neuronal cytoarchitecture during early postnatal life. In the present study, we aimed to investigate the potential effects of prenatal immune activation on early neurophenotypic presentations using a set of behavioral test battery. Female Sprague-Dawley rats were administered with 100 μg/kg LPS (intraperitoneally) at gestational days 15 and 16. During the first postnatal week, we found no significant effect on maternal behavior or mother-pup interaction by this treatment. Also, no major changes in physical developmental milestones of pups were noted from postnatal (P) days P6 to P16. Importantly, prenatal LPS-exposed pups had a significant decrease in the number and duration of ultrasonic vocalization calls at P3 and P5. Prenatal LPS treatment also led to impairments in nest-seeking behavior and odor-stroke associative learning in neonatal rats at P8 and P9. At the molecular level, we detected significant decrease in the expression of cortical 5HT1A and 5HT1B messenger RNA at P3. These data suggest that prenatal exposure to an immune activator can significantly impair the social/communicative behavior in the neonate offspring, which may be relevant to childhood and premorbid abnormalities reported in autism and schizophrenia subjects.

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Group B Streptococcus (GBS) is a commensal bacterium present in the lower genital tract of 15-30% of healthy pregnant women. GBS is the leading cause of chorioamnionitis and cerebral injuries in newborns, occurring most often in the absence of maternofetal pathogen translocation. Despite GBS being the most frequent bacterium colonizing pregnant women, no preclinical studies have investigated the impact of end-gestational maternal GBS exposure on the offspring's brain development and its behavioral correlates. Our hypothesis is that GBS-induced gestational infection/inflammation has a deleterious neurodevelopmental impact on uninfected offspring. Our goal was to study the impact of maternal GBS infection on the placental and neurodevelopmental features in the offspring using a new preclinical rat model. GBS-exposed placentas exhibited chorioamnionitis characterized by the presence of Gram-positive cocci and polymorphonuclear cells, with the latter being significantly more prominent in the labyrinth of male offspring. GBS-exposed male offspring had reduced thickness of periventricular white matter. In addition, they exhibited autistic-like behaviors, such as abnormal social interaction and communication, impaired processing of sensory information and hyperactivity. Overall, these data show for the first time that gestational exposure to GBS plays an important role in the generation of neurodevelopmental abnormalities reminiscent of human autism spectrum disorders (ASD). These results provide new evidence in favor of the role of a common and modifiable infectious/inflammatory environmental factor in human ASD pathophysiology. Autism Res 2017, 10: 233-245. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

The neural mechanisms by which maternal infections increase the risk for schizophrenia are poorly understood; however, animal models using maternal administration of immune activators suggest a role for cytokine imbalance in maternal/fetal compartments. As cytokines can potentially affect multiple aspects of neuronal development and the neuropathology of schizophrenia is believed to involve subtle temporo-limbic neurodevelopmental alterations, we investigated morphological development of the pyramidal neurons of the medial prefrontal cortex (mPFC) and hippocampus in rats that were prenatally challenged with the immune activator lipopolysaccharide (LPS). Pregnant Sprague-Dawley rats were administered with LPS (at E15- E16) or saline. The brains of offspring were processed for Golgi-Cox staining at postnatal days 10, 35 and 60. Dendritic length, branching, spine density and structure were quantified using Neurolucida software. At all ages, dendritic arbor was significantly reduced in mPFC and CA1 neurons of LPS-treated animals. Dendritic length was significantly reduced in the mPFC neurons of LPS group at P10 and 35 but returned to control values at P60. Opposite pattern was observed in CA1 region of LPS animals (normal values at P10 and 35, but a reduction at P60). LPS treatment significantly altered the structure of CA1 dendritic spines at P10. Spine density was found to be significantly lower only in layer V mPFC of P60 LPS rats. The study provides the first evidence that prenatal exposure to an immune activator dynamically affects spatio-temporal development of pyramidal neurons in mPFC and hippocampal that can potentially lead to aberrant neuronal connectivity and functions of these structures.

Background Multiple sclerosis (MS) causes pervasive motor, sensory and cognitive dysfunction. The Expanded Disability Status Scale (EDSS) is the gold standard for assessing MS disability. The EDSS is biased towards mobility and may not accurately measure MS-related disabilities in the upper limb or in cognitive functions (e.g. executive function). Objective Our objectives were to determine the feasibility of using the Kinarm robotic system to quantify neurological deficits related to arm function and cognition in MS patients, and examine relationships between traditional clinical assessments and Kinarm variables. Methods Individuals with MS performed 8 robotic tasks assessing motor, cognitive, and sensory ability. We additionally collected traditional clinical assessments and compared these to the results of the robotic assessment. Results Forty-three people with MS were assessed. Most participants could complete the robotic assessment. Twenty-six (60%) were impaired on at least one cognitive task and twenty-six (60%) were impaired on at least one upper-limb motor task. Cognitive domain task performance correlated most strongly with the EDSS. Conclusions Kinarm robotic assessment of people with MS is feasible, can identify a broad range of upper-limb motor and sensory, as well as cognitive, impairments, and complements current clinical rating scales in the assessment of MS-related disability.

Epidemiological evidence supports that maternal infection during gestation are notable risk factors for developmental mental illnesses including schizophrenia and autism. In prenatal lipopolysaccharide (LPS) model of immune activation in rats, the offspring exhibit significant impairments in behaviors mediated by central dopamine (DA) system. This study aimed to examine the temporal and regional pattern of postnatal DA development in the male offspring of pregnant Sprague-Dawley rats administered with 100 µg/kg LPS or saline at gestational days 15/16. Using ligand autoradiography, D1 and D2 dopamine receptors (D1R, D2R) and dopamine transporter (DAT) binding levels were measured in the prefrontal cortex (PFC) and sub cortical regions (dorsal striatum and nucleus accumbens core and shell) at pre pubertal (P35) and post pubertal ages (P60). We found a significant decrease in D2R ligand [3H] YM-90151-2 binding in the medial PFC (mPFC) in prenatal LPS-treated animals at P35 and P60 compared to respective saline groups. The decrease in D2R levels was not observed in the striatum or accumbens of maternal LPS-treated animals. No significant changes were observed in [3H] SCH23390 binding to D1R. However, the level of [125I] RTI-121 binding to DAT was selectively reduced in the nucleus accumbens core and shell at P35 in the prenatal LPS group. Immunohistochemical analysis showed that number of D2R immunopositive cells in infralimbic/prelimbic (IL/PL) part of mPFC was significantly reduced in the LPS group at P60. Prenatal LPS treatment did not significantly affect either the total number of mature neurons or parvalbumin (PV)-immunopositive interneurons in this region. However the number of PV and D2R co-labeled neurons was significantly reduced in the IL/PL subregion of PFC of LPS treated animals. Our data suggests D2R deficit in the PFC and PV interneurons may be relevant to understanding mechanisms of cortical dysfunctions described in prenatal infection animal models as well as schizophrenia.

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