The association of obesity with eating disorders risk: online survey of a large cohort of Russian-speaking individuals seeking medical weight correction assistance.

BACKGROUND: Eating Disorders pose a serious health risk to individuals. Often, eating disorder symptoms are overlooked when assessing obesity risk. The current cross-sectional study was focused on the search of association between disordered eating behaviors evaluated by Eating Attitudes Test 26 (EAT-26) and obesity in a large cohort of Russian-speaking adults seeking online assistance with medical weight correction. METHODS: The web-based cross-sectional study evaluated the data of online Eating Attitudes Test 26 (EAT-26) completed by 13,341 registered adult visitors of weight loss clinic website. The EAT-26 provides an overall score for potential eating disorders risk, as well as scores for three subscales: Bulimia, dieting, and oral control. Additional self-reported information about sex, weight, height, and age of respondents was used for analysis. The nonparametric analysis of variance and binominal logistic regression modeling were applied to search for an association between obesity and EAT-26 total score and subscales scores. The critical level of the significance was considered as α = 0.05. RESULTS: Women (94%) had lower BMI values but higher EAT-26 total score than men, which was indicated as statistically significant by a Wilcoxon Signed-Ranks Test (Z = - 11.80, p < 0.0001). Logistic regression for the whole cohort revealed that Bulimia subscale score was associated with higher risk of obesity (OR = 1.03, 95% CI 1.02-1.05) whereas higher score of EAT-26 oral control subscale was associated with decreased risk of obesity (OR = 0.93, 95% CI 0.91-0.95). Separate analysis for men and women showed that in men higher obesity risk was associated with higher oral control subscale scores (OR = 1.08, 95% CI 1.06-1.11); while in women both dieting and bulimia subscales scores were associated with higher obesity risk (OR = 1.02, 95% CI 1.01-1.03 and OR = 1.03, 95% CI 1.02-1.05, respectively). Older age was associated with obesity risk for both women and men. CONCLUSIONS: In a large cohort of individuals seeking medical weight correction assistance, the risk of obesity was associated with the higher EAT-26 scores, age, and sex. Moreover, different eating disorder risk profiles were associated with obesity in men and women. Higher oral control subscale score was associated with decreased risk of obesity in women, but with higher risk in men. Older age was a shared obesity risk factor for both sexes. Therefore, the use of EAT-26 would facilitate individual diagnostic assessment for specific eating disorders in different sub-cohorts. Further assessment of separate EAT-26 subscales may be important to predict sex-/age-specific risks of obesity that implies their study in the future. Obesity is a significant health problem. Different factors (e.g. social, biological, and behavioral) are important for their successful treatment. Abnormal eating behaviors may be one of the most likely predictors of increased body weight. This study aims to determine whether there is a significant association between obesity and scores on the eating behavior questionnaire-Eating Attitudes Test-26 (EAT-26)-in a large cohort of adults seeking medical weight correction assistance at a private weight loss clinic web-site. According to the study results, the association was shown for the male sex, older age, and higher Bulimia scores as measured on the EAT-26. Moreover, different EAT-26 scales were associated with obesity risks in women and men subgroups, while older age was a shared risk factor for obesity in both sexes. The findings may suggest sex-/age-specific diagnostic approach and treatment strategies for individuals with obesity.

Importance of GluA1 subunit-containing AMPA glutamate receptors for morphine state-dependency.

In state-dependency, information retrieval is most efficient when the animal is in the same state as it was during the information acquisition. State-dependency has been implicated in a variety of learning and memory processes, but its mechanisms remain to be resolved. Here, mice deficient in AMPA-type glutamate receptor GluA1 subunits were first conditioned to morphine (10 or 20 mg/kg s.c. during eight sessions over four days) using an unbiased procedure, followed by testing for conditioned place preference at morphine states that were the same as or different from the one the mice were conditioned to. In GluA1 wildtype littermate mice the same-state morphine dose produced the greatest expression of place preference, while in the knockout mice no place preference was then detected. Both wildtype and knockout mice expressed moderate morphine-induced place preference when not at the morphine state (saline treatment at the test); in this case, place preference was weaker than that in the same-state test in wildtype mice. No correlation between place preference scores and locomotor activity during testing was found. Additionally, as compared to the controls, the knockout mice showed unchanged sensitization to morphine, morphine drug discrimination and brain regional µ-opioid receptor signal transduction at the G-protein level. However, the knockout mice failed to show increased AMPA/NMDA receptor current ratios in the ventral tegmental area dopamine neurons of midbrain slices after a single injection of morphine (10 mg/kg, s.c., sliced prepared 24 h afterwards), in contrast to the wildtype mice. The results indicate impaired drug-induced state-dependency in GluA1 knockout mice, correlating with impaired opioid-induced glutamate receptor neuroplasticity.

GABA site agonist gaboxadol induces addiction-predicting persistent changes in ventral tegmental area dopamine neurons but is not rewarding in mice or baboons.

Dopamine neurons of the ventral tegmental area (VTA) are involved at early phases of drug addiction. Even the first in vivo dose of various abused drugs induces glutamate receptor plasticity at the excitatory synapses of these neurons. Benzodiazepines that suppress the inhibitory GABAergic interneurons in the VTA via facilitation of synaptic GABA(A) receptors have induced neuroplasticity in dopamine neurons due to this disinhibitory mechanism. Here, we have tested a non-benzodiazepine direct GABA site agonist 4,5,6,7-tetrahydroisoxazolol[4,5-c]pyridine-3-ol (THIP) (also known as gaboxadol) that acts preferentially via high-affinity extrasynaptic GABA(A) receptors. A single sedative dose of THIP (6 mg/kg) to mice induced glutamate receptor plasticity for at least 6 d after administration. Increased AMPA/NMDA receptor current ratio and increased frequency, amplitude, and rectification of AMPA receptor responses suggested persistent targeting of GluA2-lacking AMPA receptors in excitatory synapses of VTA dopamine neurons ex vivo after THIP administration. This effect was abolished in GABA(A) receptor δ(-/-) mice, which have a loss of extrasynaptic GABA(A) receptors. In behavioral experiments, we found neither acute reinforcement in intravenous self-administration sessions with THIP at relevant doses using a yoked control paradigm in mice nor in baboons using a standard paradigm for assessing drug abuse liability; nor was any place preference found after conditioning sessions with various doses of THIP but rather a persistent aversion in 6 mg/kg THIP-conditioned mice. In summary, we found that activation of extrasynaptic δ-subunit-containing GABA(A) receptors leads to glutamate receptor plasticity of VTA dopamine neurons, but is not rewarding, and, instead, induces aversion.

Actions of two GABAA receptor benzodiazepine-site ligands that are mediated via non-γ2-dependent modulation.

The potent sedative-hypnotic zolpidem and the convulsant methyl-6,7-dimethoxy-4-ethyl-ß-carboline-3-carboxylate (DMCM) act primarily by binding to the benzodiazepine site of the main inhibitory neurotransmitter receptor, the pentameric γ-aminobutyric acid type A receptor (GABA(A)). This binding depends critically on the wild-type F77 residue of the GABA(A) receptor γ2 subunit. Mice with γ2 subunit F77I point mutation (γ2I77 mouse line) lose the high-affinity nanomolar binding of these ligands as well as their most robust behavioral actions at low doses. Interestingly, the γ2I77 mice offer a tool to study the actions of these substances mediated via other possible binding sites of the GABA(A) receptor. In ligand autoradiographic experiments, we discovered in γ2I77 mouse brain sections a significant amount of residual non-γ2 subunit-dependent benzodiazepine site binding enriched to the striatum and septum. Zolpidem only weakly affected this residual binding at micromolar concentrations, and only a high zolpidem dose (≥ 40 mg/kg) caused sedation and deficits in motor coordination in γ2I77 mice. DMCM had an agonistic action through a secondary, low-affinity non-benzodiazepine binding site of the GABA(A) receptor in the forebrain of γ2I77 mice, and this drug also fully displaced the residual benzodiazepine-site labeling. In behavioral tests, a high dose (20mg/kg) of DMCM was sedative and modulated fear learning. DMCM, but not zolpidem, acted as an agonist in recombinant GABA(A) α1/6ß3 receptors studied using ligand binding and electrophysiological assays. Our results highlight the less well-known actions of high doses of DMCM and zolpidem that are not mediated via the γ2 subunit-containing benzodiazepine site of the GABA(A) receptor.

Nonverbal behavior of human addicts: multimetric analysis.

AIMS: Ethological approach followed by multimetric statistical analysis was applied to characterize and discriminate alcohol, heroin and dual, alcohol and heroin, dependent subjects. DESIGN: Heroin, alcohol, and dual dependent patients (n=51) after one month of stabilization of remission and control volunteers (n=34) without a history of significant drug or alcohol use were interviewed and videotaped during the interview by approbation. Nonverbal behavioral cues monitored during the interview were analyzed by means of general linear procedure followed by correlation, factor and discriminant function analyses. FINDINGS: By using this approach the attempt to discriminate addicted groups between each other failed. Therefore we found acceptable to combine subjects in one group and to suggest the similarity between alcohol and heroin dependence. It was found that principal markers of behavioral structure in addicted subjects were higher responsivity to communicate distance, less expression of affiliation behavioral pattern, low level of correlations between different behavioral patterns, and unclear factor structure. Behavioral pattern "affiliation" was identified as discriminate behavior between control and addicted subjects. CONCLUSIONS: Nonverbal cues of human behavior identified clear differences between healthy control and addictive subjects. Therefore, ethological approach described in this paper could be recommended for future use in clinical practice.

Effects of morphine and cocaine in mice with stable high aggressive and nonaggressive behavioral strategy.

The social group experience of mice with opposite aggressive and nonaggressive behavioral strategies was examined to modulate reinforcing effects of morphine and cocaine. Highly aggressive and nonaggressive male mice cohoused for long period in three-member groups were tested to self-administrate the drugs and to develop conditioned place preferring by them. Mouse triads formed by principle of descending aggression were used as a model of linear hierarchical group. The level of mouse aggression was identified previously within the stock group and during encounter with unknown intruder that continued to be stable over the time of experiment. Highly aggressive mice self-administered morphine and cocaine at higher unit concentrations (1.5 and 1.5 mg/ml) as compare with nonaggressive animals (0.5 and 0.25, 0.5, 1.0 mg/ml). Both morphine (2.5, 5.0, 10.0, and 20.0 mg/kg) and cocaine (2.5, 5.0, and 10.0 mg/kg) induced conditioned place preference in nonaggressive mice at all doses. In contrast, morphine had no effect in highly aggressive mice, while cocaine induced place conditioning at the highest doses (10 mg/kg) only. Our results illustrate that social experience in a stable group alter mouse sensitivity to the rewarding properties of drugs of abuse and social state should be taken into account in the experiments when social interactions are present.