Faculty Bibliography

Background: There is evidence from animal and in-vitro studies that THC can affect cannabinoid receptors (1 and2) in brain and periphery and influence immunological makers, and limited evidence from animal studies that it may affect epigenetic related methylation processes. THC ingestion has also been reported as a trigger for inducing schizophrenia in venerable individuals. This is less direct work on these effects in human cannabis smokers investigating these types of chemical biomarkers in peripheral blood cells. The present study further evaluated whether smoked cannabis in human subjects produced changes in cannabinoid receptors, biomarkers for DNA methylation cycle and immunorelated gene mRNA expression.
Method(s): 23 Subjects participated in an experiment in which they smoked cannabis cigarettes with one of two doses of marijuana (5.3% or 13.4% THC) or placebo (0.02%) and were evaluated driving abilities. Blood samples were drawn at baseline and several times after smoking. Plasma and WBC (PMCs) were separated and stored at -80degreeC until further analysis. Samples were analyzed for mRNA content for cannabinoid receptors 1(CBR1) and 2(CBR2), methylation and demethylating enzymes (DNMT, TET), glucocorticoid receptor (NRC3) and immunological markers (IL1B, TNFalpha) by qPCR using TaqMan probes. The results were correlated with THC whole blood levels and TCOOH baseline levels. Statistical analyzed used analysis of variance and covariance and t-test, or non-parametric equivalents for those values which were not normally distributed.
Result(s): There were no difference in background baseline characteristics of the subjects except that the higher dose THC group was older than the low dose and placebo groups, and the low dose THC group had higher baseline CBR2 mRNA levels. Both the 5.9 and 13.4 THC groups showed increased THC levels over the next 2 hours and then decreased toward baseline; the 13.4 THC dose still showed a higher THC levels than placebo at four hours. However, there were no significant differences between THC levels between the 5.9 and 13.4 doses at any time point. At the 4-hour time point after drug administration the 13.4% THC group had higher CBR2 (P = .021) and DNMT3A (P = .027) mRNA levels than the placebo group and DNMT1 mRNA levels showed a trend in the same direction (P = .056). The higher13.4 THC group had significantly higher CBR2 mRNA levels than the 5.9 dose group at several post drug administration time points, and showed trends for difference in effects for between 5.9 and 13.4 THC groups for other mRNAs. TET3 mRNA levels were higher in the 13.4 THC group at 55 minutes post-drug ingestion. When the high and lower dose THC groups were combined, none of the differences in mRNA levels from placebo remain statistically significant. Changes in THC plasma levels were not related to changes in mRNA levels.
Conclusion(s): Over the time course of this study CBR2 levels increased in human PMCs in the high dose THC group but where not accompanied by changes in immunological markers. The changes in DNMT and TET mRNAs suggest potential epigenetic effects of THC in human PMCs. Increases in DNMT metylating enzymes have been linked to some of the pathophysiological process in schizophrenia and, therefore, should be further explored as one of the potential mechanisms linking cannabism use as a trigger for schizophrenia

Alterations in glutamatergic function are well established in schizophrenia (Sz), but new treatment development is hampered by the lack of translational pathophysiological and target engagement biomarkers as well as by the lack of animal models that recapitulate the pathophysiological features of Sz. Here, we evaluated the rodent auditory steady state response (ASSR) and long-latency auditory event-related potential (aERP) as potential translational markers. These biomarkers were assessed for their sensitivity to both the N-methyl-d-aspartate receptor (NMDAR) antagonist phencyclidine (PCP) and to knock-out (KO) of Serine Racemase (SR), which is known to lead to Sz-like alterations in function of parvalbumin (PV)-type cortical interneurons. PCP led to significant increases of ASSR that were further increased in SRKO-/-, consistent with PV interneuron effects. Similar effects were observed in mice with selective NMDAR KO on PV interneurons. By contrast, PCP but not SRKO reduced the amplitude of the rodent analog of the human N1 potential. Overall, these findings support use of rodent ASSR and long-latency aERP, along with previously described measures such as mismatch negativity (MMN), as translational biomarkers, and support SRKO mice as a potential rodent model for PV interneuron dysfunction in Sz.

Background: Some biochemical abnormalities underlying schizophrenia, involve differences in methylation and methylating enzymes, their target genes, and genes uncovered by RNA seq analysis. We present results of a larger study measuring differences in mRNA in lymphocytes (PBL) and brain of chronic schizophrenics (CSZ) and non-psychotic controls (NPC), examining the differential effect of sex and antipsychotic drug treatment.
Method(s): We studied mRNA in PBL of 61 CSZ and 49 NPC using qPCR assays. We studied DNMT1 and GAD67 in brains of 19 CSZ, 26 NPC, and 19 subjects with bipolar disorder (BP).
Result(s): DNMT1 and DNMT3A mRNAs were significantly (P<.01) higher in PBL only in male CSZ subjects, and females showed a trend in the opposite direction. The GAD1, glucocorticoid receptor (NR3C1) and CNTNPA2 mRNAs were significantly higher in CSZ than NPC. The FPRF3 mRNA was significantly lower in CSZ vs NPC. When clozapine treatment was examined, it was clear that for the GABAergic mRNAs (GAD1, GAD67, GAD25), and for NR3C1-B, CNTNPA2, and IMPA2 mRNAs, that clozapine treated CSZ were primarily responsible for the difference from NPC. DNMT1 was significantly higher and GAD67 significantly lower in frontal cortex of brains of CSZ and BP than NPC but there were no sex different effects in this older age brain sample.
Conclusion(s): It is important to consider sex and antipsychotic drug treatment in comparing mRNA levels in schizophrenic patients to controls, since some of the differences are only present in male subjects and other may be explained by clozapine treatment rather than primarily diagnosis. Supported By: NIH 1R01MH101043, and Philanthropic Grant Keywords: Schizophrenia, mRNA, Sex-Specific, Clozapine
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Background: Misfolding of the pre-synaptic protein, alpha-synuclein (alpha-Syn), and formation of abnormal cytoplasmic aggregates, have been implicated in the progressive degeneration and synaptic dysfunction associated with Parkinson's disease (PD) and a number of related disorders. Several lines of evidence have also implicated disturbances in alpha-synuclein in the pathophysiology of depression. For example, depression is highly prevalent in PD and other synucleopathies, and often precedes motor symptoms. In preclinical experiments overexpression of human alpha-Syn has been linked to a depressive-like phenotype, and with factors implicated in depression including disruption of monoamine transporters, degeneration of dopamine neurons and microglial and HPA-axis activation and release of proinflammatory cytokines. Despite these findings, there are no studies that have examined CSF alpha-Syn concentration in depression and its relationship to symptoms, monoaminergic indices and markers of synaptic dysfunction such as neurogranin (Ng) and neuroinflammation (IL-6, IL-8).
Method(s): A total of 51 individuals participated in a 3-year longitudinal study examining possible Abeta disturbances in depression and agreed to have a lumbar puncture. Of these 51 individuals, 47 showed (28 MDD and 19 controls) no MRI evidence of confluent deep or periventricular white matter hyperintensities and had a Mini-Mental State Examination (MMSE) score of 28 or above were included in this study. Participants completed a clinical evaluation including the Hamilton Depression Scale (HAMD) and neuropsychological evaluations. Memory performance from the neuropsychological assessment was determined by Total Recall on the Buschke Selective Reminding Test, Delayed Recall, and the Recency Ratio. CSF alpha-Syn (ng/mL), Ng (pg/mL), HVA, 5-HIAA, MHPG, IL-6, and IL-8, cortisol (ug/dL) were determined using previously published methods. Mann-U Whitney tests were conducted to compare depressed and controls. Spearman correlations were computed for depressed subjects and controls, separately, and results for the depress subjects only are reported below.
Result(s): There were no significant differences in alpha-Syn (p = 0.21), Ng (p = 0.35), IL6 (p = 0.213), IL8 (p = 0.633), HVA (p = 0.665), 5-HIAA (p = 0.442) and MHPG (p = 0.845) between the depressed and the control group. In depressed subjects only, alpha-Syn was significantly positively correlated with Ng (rho = 0.783, p < 0.001), and negatively correlated with cortisol (rho =-0.425, p = 0.024) and IL-8 (rho =-0.435, p = 0.021), with a trend for IL-6 (rho =-0.355, p = 0.064). Interestingly, there was no significant relationship with depressive symptoms at Baseline (p = .36). alpha-Syn was not correlated with memory performance on the selected assessments (p values >= 0.400). Ng displayed a trend correlation with Rr (rho = 0.482, p = 0.009, adjusted p = 0.081), consistent with expectations, but was not otherwise correlated with the other variables (adjusted p values >= 0.350).
Conclusion(s): In depressed subjects only, CSF alpha-Syn was significantly positively related with CSF Ng. Similar correlations have been reported in PD and together with reductions in CSF levels ascribed to impaired synaptic activity in that population from increased brain deposits. Given that CSF alpha-Syn did not correlate with cognitive and depressive symptoms, the significance of this finding, if any, remains to be determined. Lower CSF alpha-Syn in PD and Lewy-Body Dementia have been attributed to its entrapment in brain parenchyma. Therefore, the negative correlations between CSF alpha-Syn and proinflammatory cytokines and cortisol in depressed subjects only are consistent with increased glial and HPA-axis activation, secondary to greater alpha-Syn brain deposits. This preliminary finding complements reports of increased serum alpha-Syn levels and its mRNA expression associated with severity of depressive symptoms in younger populations

Background: Some of the biochemical abnormalities underlying schizophrenia, studied in both brain and peripheral blood, involve differences in methylation and methylating enzymes, as well as other genes uncovered by chip seq or RNA seq analysis. of enzymes and some of the target genes. However, few of these studies have examined the effect of sex and drug treatment on the differences between chronic schizophrenics and controls. We present results of a larger study measuring differences in mRNA in lymphocytes of chronic schizophrenics (CSZ) and non-psychotic controls (NPC) emphasizing the differential effect os sex and antipsychotic drug treatment on the different biochemical findings.
Method(s): We studied mRNA in lymphocytes of 61 CSZ and 49 NPC subjects using qPCR assays with TaqMan probes for multiple genes to assess mRNA levels for DNMT, TET, GABAergic genes, Glucocorticoid receptor, BDNF, and several genes with high hits from RNA sequence analysis. Statistical analysis tested the effects of diagnostic status (CSZ vs. NPC) on these mRNA levels and investigated the effects of sex differences and differences in antipsychotic drug treatment on the mRNA levels in CSZ and NPC.
Result(s): DNMT1 and DNMT3A mRNAs were significantly (P < 0.01) higher only in male CSZ subjects, with the small sample of females showing no statistical difference between CSZ and NPC, but a trend in the opposite direct from the male CSZ vs NPC comparison. Several other mRNA's differences between CSZ and NPC showed a trend for a greater diagnostic difference in males than in females. The GAD1, glucocorticoid receptor (NR3C1) and CNTNPA2 mRNAs were significantly (P < 0.01) higher in CSZ than NPC. The FPRF3 mRNA was significantly (P < 0.03) lower in CSZ vs NPC, and the GAD67 mRNA showed a trend in the same direction for males (P < 0.10). In CSZ currently treated with clozapine, GABAergic mRNAs (GAD1, GAD67, GAD25) mRNA were significantly higher than in patients not treated with clozapine. CSZ treated with clozapine had significantly lower TET1 mRNA. There was a trend (P < 0.10) for NR3C1-B mRNA to be higher in clozapine patients. When we did analysis of differences between CSZ and NPC subjects, incorporating the clozapine treatment variable, it was clear that for the GABAergic mRNAs (GAD1, GAD67, GAD25), and for NR3C1-B, CNTNPA2, and IMPA2 mRNAs, that clozapine treated CSZ were primarily responsible for the difference from NPC, whereas non-clozapine treated CSZ had mRNA values more similar to NPC controls.
Conclusion(s): It is important to consider sex and antipsychotic drug treatment in comparing mRNA levels in in schizophrenic patients to controls, since some of the differences are only present in male subjects and other may be explained by clozapine treatment rather than primarily diagnosis. Many previous studies of similar differences in post-mortem brain samples, and some studies of methylation differences using peripheral blood cells, have not examined sex and drug treatment effects, and these could be possible confounds in interpreting diagnostic differences in these biochemical effects

RATIONALE/BACKGROUND:Weight gain during treatment with antipsychotics is a prominent side-effect, especially with some second-generation antipsychotics, such as olanzapine and clozapine, and pharmacological treatments which ameliorate this side-effect are important to investigate. Decreases in histaminergic transmission in the brain induced by antipsychotics may be one of the mechanisms contributing to weight gain. Since betahistine is a histaminergic agonist, it may potentially counteract the weight gain effects of antipsychotics. METHOD/METHODS:We conducted a double-blind placebo-controlled study to evaluate the effects of 12 weeks of treatment with betahistine (N = 29) or placebo (N = 22) in adolescents and adults on anthropomorphically measured weight-related parameters, appetite, and fasting glucose-lipid and leptin levels in 51 patients treated with first and/or second-generation antipsychotics who had gained weight during treatment or had high body-mass-index (BMI). Psychopathology and side-effects were also assessed with relevant scales. RESULTS:In a sub-group of patients being treated with olanzapine or clozapine (n = 26), betahistine was significantly (P < .05) better than placebo in preventing increases in weight (3.1 kg less weight gain than placebo), BMI, and waist circumference. Betahistine did not decrease weight or BMI in patients treated with other antipsychotics. There was also no effect of betahistine on preventing weight or BMI gain in the total combined sample of all subjects. Betahistine did not significantly improve appetite or glucose-lipid measures in either subgroup. There were no significant differences in side-effects or psychopathology changes in the betahistine- vs. placebo-treated patients. CONCLUSIONS:These results suggest that betahistine may potentially be a useful adjunctive drug for decreasing weight gain in patients treated with antipsychotics that are potent histamine antagonists, such as olanzapine or clozapine, but may not be useful for this purpose in patients on other antipsychotic medications. The results justify larger placebo-controlled studies to further confirm these effects before specific recommendations can be made for routine use.

Neurofilament (NFL) proteins have recently been found to play unique roles in synapses. NFL is known to interact with the GluN1 subunit of N-methyl-D-aspartic acid (NMDAR) and be reduced in schizophrenia though functional consequences are unknown. Here we investigated whether the interaction of NFL with GluN1 modulates synaptic transmission and schizophrenia-associated behaviors. The interaction of NFL with GluN1 was assessed by means of molecular, pharmacological, electrophysiological, magnetic resonance spectroscopy (MRS), and schizophrenia-associated behavior analyses. NFL deficits cause an NMDAR hypofunction phenotype including abnormal hippocampal function, as seen in schizophrenia. NFL-/- deletion in mice reduces dendritic spines and GluN1 protein levels, elevates ubiquitin-dependent turnover of GluN1 and hippocampal glutamate measured by MRS, and depresses hippocampal long-term potentiation. NMDAR-related behaviors are also impaired, including pup retrieval, spatial and social memory, prepulse inhibition, night-time activity, and response to NMDAR antagonist, whereas motor deficits are minimal. Importantly, partially lowering NFL in NFL+/- mice to levels seen regionally in schizophrenia, induced similar but milder NMDAR-related synaptic and behavioral deficits. Our findings support an emerging view that central nervous system neurofilament subunits including NFL in the present report, serve distinctive, critical roles in synapses relevant to neuropsychiatric diseases.

Binge alcohol (ethanol) drinking is associated with profound adverse effects on our health and society. Rimonabant (SR141716A), a CB1 receptor inverse agonist, was previously shown to be effective for nicotine cessation and obesity. However, studies using rimonabant were discontinued as it was associated with an increased risk of depression and anxiety. In the present study, we examined the pharmacokinetics and effects of AM4113, a novel CB1 receptor neutral antagonist on binge-like ethanol drinking in C57BL/6J mice using a two-bottle choice drinking-in-dark (DID) paradigm. The results indicated a slower elimination of AM4113 in the brain than in plasma. AM4113 suppressed ethanol consumption and preference without having significant effects on body weight, ambulatory activity, preference for tastants (saccharin and quinine) and ethanol metabolism. AM4113 pretreatment reduced ethanol-induced increase in dopamine release in nucleus accumbens. Collectively, these data suggest an important role of CB1 receptor-mediated regulation of binge-like ethanol consumption and mesolimbic dopaminergic signaling, and further points to the potential utility of CB1 neutral antagonists for the treatment of binge ethanol drinking.

There is a substantive clinical literature on classical hallucinogens, most commonly lysergic acid diethylamide (LSD) for the treatment of alcohol use disorder. However, there has been no published research on the effect of LSD on alcohol consumption in animals. This study evaluated the effect of LSD in mice using a two-bottle choice alcohol drinking paradigm. Adult male C57BL/6J mice were exposed to ethanol to develop preference and divided into three groups of equal ethanol consumption, and then treated with single intraperitoneal injection of saline or 25 or 50 μg/kg LSD and offered water and 20% ethanol. The respective LSD-treated groups were compared to the control group utilizing a multilevel model for repeated measures. In mice treated with 50 μg/kg LSD ethanol consumption was reduced relative to controls (p = 0.0035), as was ethanol preference (p = 0.0024), with a group mean reduction of ethanol consumption of 17.9% sustained over an interval of 46 days following LSD administration. No significant effects on ethanol consumption or preference were observed in mice treated with 25 μg/kg LSD. Neither total fluid intake nor locomotor activity in the LSD-treated groups differed significantly from controls. These results suggest that classical hallucinogens in the animal model merit further study as a potential approach to the identification of targets for drug discovery and investigation of the neurobiology of addiction.