Wireless optogenetic stimulation on the prelimbic to the nucleus accumbens core circuit attenuates cocaine-induced behavioral sensitization.

Behavioral sensitization is defined as the heightened and persistent behavioral response to repeated drug exposure as a manifestation of drug craving. Psychomotor stimulants such as cocaine can induce strong behavioral sensitization. In this study, we explored the effects of optogenetic stimulation of the prelimbic (PL) to the nucleus accumbnes (NAc) core on the expression of cocaine-induced behavioral sensitization.

Manipulation of radixin phosphorylation in the nucleus accumbens core modulates risky choice behavior.

Ezrin-Radixin-Moesin (ERM) proteins are actin-binding proteins that contribute to morphological changes in dendritic spines. Despite their significant role in regulating spine structure, the role of ERM proteins in the nucleus accumbnes (NAcc) is not well known, especially in in the context of risk-reward decision-making. Here, we measured the relationship between synaptic excitation and inhibition (E/I ratio) from medium spiny neurons in the NAcc core obtained in the rat after a rat gambling task (rGT).

Glycogen Synthase Kinase 3β Is a Key Regulator in the Inhibitory Effects of Accumbal Cocaine- and Amphetamine-Regulated Transcript Peptide 55-102 on Amphetamine-Induced Locomotor Activity.

Microinjection of cocaine- and amphetamine-regulated transcript (CART) peptide 55-102 into the nucleus accumbens (NAcc) core significantly attenuates psychostimulant-induced locomotor activity. However, the molecular mechanism remains poorly understood. We examined the phosphorylation levels of Akt, glycogen synthase kinase 3β (GSK3β), and glutamate receptor 1 (GluA1) in NAcc core tissues obtained 60 min after microinjection of CART peptide 55-102 into this site, followed by systemic injection of amphetamine (AMPH).

Differential transcriptome profile underlying risky choice in a rat gambling task.

Background And Aims: Proper measurement of expected risk is important for making rational decisions, and maladaptive decision making may underlie various psychiatric disorders. However, differentially expressed genetic profiling involved in this process is still largely unknown. A rodent version of the gambling task (rGT) has been developed to measure decision-making by adopting the same principle of Iowa Gambling Task in humans.

Disruption of amphetamine sensitization by alteration of dendritic thin spines in the nucleus accumbens core.

Repeated injections of psychomotor stimulants like amphetamine (AMPH) to rodents can induce behavioral sensitization, which represents a long-lasting craving that is usually observed in human addicts. Behavioral sensitization is characteristically maintained for a long duration, accompanied by structural plasticity in some brain areas involved in reward circuitry. For example, it increased dendritic spine densities in the nucleus accumbens (NAcc), which is considered to reflect neurophysiological changes at this site, leading to addictive behaviors.

Decrease of glycogen synthase kinase 3β phosphorylation in the rat nucleus accumbens shell is necessary for amphetamineinduced conditioned locomotor activity.

Phosphorylation levels of glycogen synthase kinase 3β (GSK3β) negatively correlated with psychomotor stimulant-induced locomotor activity. Locomotor sensitization induced by psychomotor stimulants was previously shown to selectively accompany the decrease of GSK3β phosphorylation in the nucleus accumbens (NAcc) core, suggesting that intact GSK3β activity in this region is necessary for psychomotor stimulants to produce locomotor sensitization. Similarly, GSK3β in the NAcc was also implicated in mediating the conditioned effects formed by the associations of psychomotor stimulants.

Soft subdermal implant capable of wireless battery charging and programmable controls for applications in optogenetics.

Optogenetics is a powerful technique that allows target-specific spatiotemporal manipulation of neuronal activity for dissection of neural circuits and therapeutic interventions. Recent advances in wireless optogenetics technologies have enabled investigation of brain circuits in more natural conditions by releasing animals from tethered optical fibers. However, current wireless implants, which are largely based on battery-powered or battery-free designs, still limit the full potential of in vivo optogenetics in freely moving animals by requiring intermittent battery replacement or a special, bulky wireless power transfer system for continuous device operation, respectively.

Immunohistochemical detection of GluA1 subunit of AMPA receptor in the rat nucleus accumbens following cocaine exposure.

α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors are differentially regulated in the nucleus accumbens (NAcc) of the brain after cocaine exposure. However, these results are supported only by biochemical and electrophysiological methods, but have not been validated with immunohistochemistry. To overcome the restriction of antigen loss on the postsynaptic target molecules that occurs during perfusion-fixation, we adopted an immersion-fixation method that enabled us to immunohistochemically quantify the expression levels of the AMPA receptor GluA1 subunit in the NAcc.

Ezrin-radixin-moesin proteins are regulated by Akt-GSK3β signaling in the rat nucleus accumbens core.

The ezrin-radixin-moesin (ERM) proteins are a family of membrane-associated proteins known to play roles in cell-shape determination as well as in signaling pathways. We have previously shown that amphetamine decreases phosphorylation levels of these proteins in the nucleus accumbens (NAcc), an important neuronal substrate mediating rewarding effects of drugs of abuse. In the present study, we further examined what molecular pathways may be involved in this process.

Impulsive Action and Impulsive Choice Are Differentially Expressed in Rats Depending on the Age at Exposure to a Gambling Task.

Impulsivity is considered an important feature associated with the development of numerous psychiatric disorders, including addictions. In the behavioral approach, impulsivity can be broadly divided into two distinct subtypes: impulsive action and choice. In the present study, we used a rodent version of the gambling task (rGT) to examine how impulsive action and impulsive choice are differentially influenced by difference in age at exposure (i.

Leptin in the nucleus accumbens blocks the increase of GluA1 phosphorylation induced by acute cocaine administration.

Leptin in the rat's nucleus accumbens (NAcc) core has previously shown to disrupt the effects of acute administration of cocaine on both locomotor activity and the phosphorylation levels of glycogen synthase kinase 3β. In the present study, we further measured the phosphorylation levels of GluA1 after bilateral microinjections of leptin in this site followed by acute administration of cocaine. Interestingly, leptin in the NAcc core significantly blocks the increase of GluA1 phosphorylation levels at serine 845 induced by acute administration of cocaine.

Leptin in the nucleus accumbens core disrupts acute cocaine effects: Implications for GSK3β connections.

An adipose-derived peptide hormone, leptin, has a regulatory role in reward-related behaviors produced by drugs of abuse. Although it is known that leptin modulates mesolimbic dopaminergic pathways, little is known about its direct role in the nucleus accumbens (NAcc). In the present study, we measured acute cocaine-induced locomotor activity in the rat and the phosphorylation levels of GSK3β after bilateral microinjections of leptin into the NAcc core.

Interaction between trait and housing condition produces differential decision-making toward risk choice in a rat gambling task.

Poor decision-making is a core problem in psychiatric disorders such as pathological gambling and substance abuse. Both trait and environmental factors are considerably important to affect decision-making. However, it has not yet been systematically shown how they interact to affect risk preference in animal models evaluating decision-making.

Locomotor sensitization is expressed by ghrelin and D1 dopamine receptor agonist in the nucleus accumbens core in amphetamine pre-exposed rat.

Ghrelin modulates mesolimbic dopaminergic pathways in the brain in addition to its role in feeding. We investigated what roles ghrelin in the nucleus accumbens (NAcc) core may play in mediating locomotor activating effects of amphetamine (AMPH). First, when rats were administered with AMPH (1 mg/kg, i.

Cocaine inhibits leptin-induced increase of the cocaine- and amphetamine-regulated transcript peptide in the nucleus accumbens in rats.

Two well-known appetite-regulatory peptides, leptin and cocaine- and amphetamine-regulated transcript (CART), are known to be involved in the brain rewarding pathway. However, it is not yet known how they interact in the nucleus accumbens, an important region mediating the rewarding effects of drugs of abuse. Using the immunoassay method, we found that a microinjection of leptin into the nucleus accumbens core induces an immediate and transient increase of the CART peptide in this site, whereas these effects were inhibited by cocaine.

Amphetamine dephosphorylates ERM proteins in the nucleus accumbens core and lithium attenuates its effects.

The ezrin-radixin-moesin (ERM) proteins have been implicated not only in cell-shape determination but also in cellular signaling pathway. We have previously shown that cocaine decreases phosphorylation levels of these proteins in the nucleus accumbens (NAcc), an important brain area mediating addictive behaviors. Here we further revealed that the phosphorylation levels of ERM were decreased in the NAcc core, but not in the shell, by a single injection of amphetamine (AMPH) (2 mg/kg, i.

Carbohydrate intake interacts with SNP276G>T polymorphism in the adiponectin gene to affect fasting blood glucose, HbA1C, and HDL cholesterol in Korean patients with type 2 diabetes.

Background/objective: The SNP276G>T polymorphism in the adiponectin gene has been reported to be associated with type 2 diabetes and impaired glucose tolerance. The objective of this study was to examine whether SNP276G>T polymorphism influences the blood glucose levels in relation to dietary carbohydrate intake.

Subjects/methods: In an ongoing, prospective study, 673 patients with type 2 diabetes (339 men and 334 women, aged 40-85 years) were recruited from one of two diabetes clinics in Seoul, Korea.

Microinjection of ghrelin in the nucleus accumbens core enhances locomotor activity induced by cocaine.

Ghrelin has a regulatory role not only in the rewarding aspect for feeding but also in drug addiction by interaction with mesolimbic dopaminergic pathways in the brain. Previously it has been shown that systemic ghrelin enhances cocaine-induced hyper-locomotor activity. However, it has not been determined yet what effects ghrelin may produce on cocaine-induced locomotor behavior when microinjected into the nucleus accumbens core, where cocaine actually produces its locomotor activating effects.

Inhibition of PKMζ in the nucleus accumbens core blocks the expression of locomotor sensitization induced by amphetamine.

Behavioral sensitization is a form of drug-induced, long-lasting, non-associative memory. Protein kinase M zeta (PKMζ) has been shown to play a role in maintaining associative long-term memory in various brain regions. In the present study, rats were pre-exposed to either saline or amphetamine (AMPH) (1 mg/kg, i.

Development and evaluation of a food frequency questionnaire for Vietnamese female immigrants in Korea: the Korean Genome and Epidemiology Study (KoGES).

The objectives of this study were to develop a food-frequency questionnaire (FFQ) for Vietnamese female immigrants in Korea and to evaluate the validity of the FFQ. A total of 80 food items were selected in developing the FFQ according to consumption frequency, the contribution of energy and other nutrients, and the cooking methods based on one-day 24 hour recall (24HR) from 918 Vietnamese female immigrants between November 2006 and November 2007. The FFQ was validated by comparison with 24HR of 425 Vietnamese female immigrants between November 2008 and August 2009.

Hypoadiponectinemia is strongly associated with metabolic syndrome in Korean type 2 diabetes patients.

Objective: To evaluate the relationship between serum adiponectin level, dietary intake, and metabolic syndrome (MetS) in type 2 diabetes mellitus (DM) patients, and to identify factors associated with serum adiponectin level.

Methods: A cross-sectional study was performed using 789 type 2 DM patients (406 men and 383 women) 40-80 years old. Subjects were classified into 3 groups on the basis of serum adiponectin level.

Dietary factors related to body weight in adult Vietnamese in the rural area of Haiphong, Vietnam: the Korean Genome and Epidemiology Study (KoGES).

The objectives of this study were to examine the association between dietary factors and underweight and overweight adult Vietnamese living in the rural areas of Vietnam. A cross-sectional study of 497 Vietnamese aged 19 to 60 years (204 males, 293 females) was conducted in rural areas of Haiphong, Vietnam. The subjects were classified as underweight, normal weight, and overweight based on BMI.

Tumor necrosis factor (TNF-alpha) and C-reactive protein (CRP) are positively associated with the risk of chronic kidney disease in patients with type 2 diabetes.

Purpose: Chronic low-grade inflammation may induce chronic kidney disease in patients with type 2 diabetes. This study investigated the relation between inflammatory biomarkers and chronic kidney disease in patients with type 2 diabetes, which has not yet been reported in Asian populations.

Materials And Methods: A cross-sectional study was performed in 543 patients recruited from diabetic clinics for an ongoing, prospective study.

Psychological distress is associated with inadequate dietary intake in Vietnamese marriage immigrant women in Korea.

Previous studies have reported that the nutritional status of Vietnamese female marriage immigrants in Korea is inadequate. And the mediation of acculturation stress can contribute to problems in their eating practices and dietary intakes. This study examines an association between psychological distress and inadequate dietary intake in Vietnamese female marriage immigrants living in Korea.

Balloon dilatation for corrosive esophageal strictures in children: radiologic and clinical outcomes.

Objective: We retrospectively evaluated the effectiveness of the esophageal balloon dilatation (EBD) in children with a corrosive esophageal stricture.

Materials And Methods: The study subjects included 14 patients (M:F = 8:6, age range: 17-85 months) who underwent an EBD due to a corrosive esophageal stricture. The causative agents for the condition were glacial acetic acid (n = 9) and lye (n = 5).