CREB1 Genotype Modulates Adaptive Reward-Based Decisions in Humans

Regional gene expression patterns are associated with task-specific brain activation during reward and emotion processing measured with functional MRI

The exploration of the spatial relationship between gene expression profiles and task-evoked response patterns known to be altered in neuropsychiatric disorders, for example depression, can guide the development of more targeted therapies. Here, we estimated the correlation between human transcriptome data and two different brain activation maps measured with functional magnetic resonance imaging (fMRI) in healthy subjects. Whole-brain activation patterns evoked during an emotional face recognition task were associated with topological mRNA expression of genes involved in cellular transport. In contrast, fMRI activation patterns related to the acceptance of monetary rewards were associated with genes implicated in cellular localization processes, metabolism, translation, and synapse regulation. An overlap of these genes with risk genes from major depressive disorder genome-wide association studies revealed the involvement of the master regulators TCF4 and PAX6 in emotion and reward processing. Overall, the identification of stable relationships between spatial gene expression profiles and fMRI data may reshape the prospects for imaging transcriptomics studies.

BDNF and p-GSK3β in the hippocampus mediate the impairment of delay-based decision making in morphine-dependent rats

It has been shown that morphine addiction impairs cognitive brain functions. However, there is no document to consider the effect of morphine dependency and its withdrawal on cost-benefit decision making and its molecular pathways. The present study aimed to evaluate the influences of morphine dependency and its withdrawal on delay-based decision making and the BDNF, p-GSK3β, and p-CREB levels during the decision making in the hippocampus. Different groups of rats were trained in a T-maze with the delay-based cost-benefit decision-making paradigm. After that, the animals were dependent on morphine, and the percentage of the high reward preference was evaluated. After behavioral tests, BDNF level, p-GSK3β/GSK3β ratio, and p-CREB/CREB ratio in the hippocampus measured by Western blot analysis. The gathered data showed that level of BDNF enhanced while p-GSK3β/GSK3β ratio and p-CREB/CREB ratio in the hippocampus did not change during delay-based decision making. In morphine-dependent rats, the p-GSK3β/GSK3β ratio increased, the BDNF level and p-CREB/CREB ratio did not change in the decision making procedure. After withdrawal from morphine, the BDNF level raised while p-GSK3β/GSK3β ratio and p-CREB/CREB ratio did not change compared to the addiction group. The data declared that BDNF in the hippocampus has a critical role in delay-based decision making. Change in p-CREB in the hippocampus is not related to decision making in normal and morphine-dependent rats. P-GSK3 in the hippocampus is not involved in the decision making in normal rats, but during decision making in morphine-dependent rats, its level increased.

Impairment of cost-benefit decision making in morphine-dependent rats is partly mediated via the alteration of BDNF and p-CREB levels in the nucleus accumbens

The ability to choose goals based on decision usefulness or the time required to reach the goals chosen are important aspects of decision making. There is considerable evidence in the literature indicating the fact that drug abuse affects different aspects of cognition. In the current study, we assessed the effects of morphine dependence and its withdrawal on cost-benefit decision making and furthermore the involvement of BDNF and p-CREB in the nucleus accumbens, a key brain area involved in decision making was measured. Different groups of male Wistar rats were trained in an effort-based and/or delay-based form of cost-benefit T-maze decision-making task. Thereafter, the animals were morphine dependent and the percentage of the high reward preference was evaluated. After behavioral tests, the BDNF level, and p-CREB/CREB ratio were measured by Western blot analysis. The results showed that during effort-based but not delay-based decision making, BDNF and p-CREB levels increased. During effort-based decision making in morphine dependent rats, BDNF decreased but there was no significant change in p-CREB. Besides, during delay-based decision making in the morphine dependent group, both BDNF and p-CREB did not show any significant change. These findings revealed that BDNF and p-CREB/CREB ratio in the NAc are essential factors for effort-based but not delay-based decision making. In addition, impairment of effort-based decision making in morphine dependent rats is related to the decrease of BDNF level but not p-CREB/CREB ratio in the NAc. However, delay-based decision making defects in morphine dependent rats did not associate with the change in BDNF and p-CREB levels in the NAc.

Naloxone-precipitated withdrawal ameliorates impairment of cost-benefit decision making in morphine-treated rats: Involvement of BDNF, p-GSK3-β, and p-CREB in the amygdala

Several studies indicated that morphine administration impairs cognitive brain functions. Therefore, in the current study, we investigated the effect of subchronic exposure to morphine and its withdrawal on effort- and/or delay-based forms of cost-benefit decision making and alterations in p-CREB/CREB ratio, p-GSK3β/GSK3β ratio, and BDNF level during decision making in the amygdala. Our data displayed an impairment of both forms of cost-benefit decision making following subchronic exposure to morphine. However, preference of high reward/high effort and/or high delay reward increased after naloxone injection. In molecular section, levels of BDNF and p-CREB/CREB ratio increased during cost-benefit decision making while p-GSK3β/GSK3β ratio decreased in both forms of decision making. In morphine-treated rats, level of BDNF and p-CREB/CREB ratio reduced during both forms of decision making while p-GSK3β/GSK3β ratio increased during delay-based and did not have a significant difference with the control group during effort-based decision making. On the withdrawal day, BDNF level raised while p-GSK3β/GSK3β ratio attenuated compared to morphine-treated group in both form of decision making. In addition, p-CREB/CREB ratio increased only during delay-based decision making on the withdrawal day. In conclusion, our data revealed that subchronic exposure to morphine interferes with the cost-benefit decision making may be via changes in level of BDNF, p-CREB/CREB and p-GSK3β/GSK3β ratio in the amygdala.

Cross-Sectional and Longitudinal Effects of CREB1 Genotypes on Individual Differences in Memory and Executive Function: Findings from the BLSA

Purpose: Previously, we have shown that the SNP rs10932201 genotype of the cyclic AMP responsive element binding protein 1 gene (CREB1) contributes to individual differences in executive and memory function at the neural system and behavioral levels in healthy, young adults. However, longitudinal effects of CREB1 genotypes on cognition have not yet been addressed. Furthermore we were interested in replicating associations between CREB1 genotypes and human cognition in previous cross-sectional studies and explore whether APOE𝜀4 status might modify these relations. Materials and Methods: We investigated whether common, independent tag SNPs within CREB1 (rs2253206, rs10932201, rs6785) influence individual differences in age-related longitudinal change and level of executive function and memory performance independent of baseline age, sex, APOE𝜀4 status, and education. Our analysis included data from cognitively unimpaired older adults participating in the Baltimore Longitudinal Study of Aging. Eleven measures from six cognitive tests (sample sizes range 617-786) were analyzed using linear mixed effects and generalized estimating equations models. Mean baseline age ranged from 50 to 69 years and mean time of follow-up (interval) ranged from 8 to 22 years. Results: We found significant effects of all three CREB1 SNPs on performance level and/or longitudinal change in performance based on eight measures assessing semantic memory, episodic memory, or both executive function and semantic memory. SNP rs10932201 showed the most significant and largest effect (Cohen's d = -0.70, p < 0.01) on age-related longitudinal decline of semantic memory. Additionally, we show interactions between all three CREB1 SNPs and APOE𝜀4 status on age-related longitudinal declines and levels of memory and executive function. Conclusion: Our results suggest that CREB1 genotypes independently and by interactions with APOE𝜀4 status contribute to individual differences in cognitive aging.

Single nucleotide polymorphism near CREB1, rs7591784, is associated with pretreatment methamphetamine use frequency and outcome of outpatient treatment for methamphetamine use disorder

Although stimulant dependence is highly heritable, few studies have examined genetic influences on methamphetamine dependence. We performed a candidate gene study of 52 SNPs and pretreatment methamphetamine use frequency among 263 methamphetamine dependent Hispanic and Non-Hispanic White participants of several methamphetamine outpatient clinical trials in Los Angeles. One SNP, rs7591784 was significantly associated with pretreatment methamphetamine use frequency following Bonferroni correction (p < 0.001) in males but not females. We then examined rs7591784 and methamphetamine urine drug screen results during 12 weeks of outpatient treatment among males with treatment outcome data available (N = 94) and found rs7591784 was significantly associated with methamphetamine use during treatment controlling for pretreatment methamphetamine use. rs7591784 is near CREB1 and in a linkage disequilibrium block with rs2952768, previously shown to influence CREB1 expression. The CREB signaling pathway is involved in gene expression changes related to chronic use of multiple drugs of abuse including methamphetamine and these results suggest that variability in CREB signaling may influence pretreatment frequency of methamphetamine use as well as outcomes of outpatient treatment. Medications targeting the CREB pathway, including phosphodiesterase inhibitors, warrant investigation as pharmacotherapies for methamphetamine use disorders.