Cluster of Differentiation 147 (CD147) serves as a promoter of atherosclerosis in patients with cerebral infarction.

OBJECTIVE: The aim of this study was to investigate the correlations of cluster of differentiation 147 (CD147) with plaque stability of carotid atherosclerosis (AS), degree of stenosis, inflammatory factors, matrix metalloproteinase-9 (MMP-9) expression and vascular endothelial function in patients with cerebral infarction. PATIENTS AND METHODS: A total of 50 patients diagnosed with cerebral infarction (cerebral infarction group), 70 patients diagnosed with AS plaque (plaque group, with no infarction but plaques only) and 30 healthy people receiving physical examination (control group) in our hospital from March 2018 to July 2019 were collected. The levels of biochemical indexes, CD147, MMP-9, vascular endothelial function indexes [endothelin-1 (ET-1) and C-reactive protein (CRP)] and inflammatory factors [interleukin-10 (IL-10), IL-16 and tumor necrosis factor-alpha (TNF-α)] in the blood of each group of patients were detected via radioimmunoassay and enzyme-linked immunosorbent assay (ELISA). Moreover, ultrasonic examination and Gensini score system were applied to score the degree of carotid stenosis in cerebral infarction group. Finally, the differences in various parameters were compared among the three groups, and the correlations of CD147 with different indexes were evaluated using Spearman method. RESULTS: Compared with those in control group, the levels of CD147, MMP-9, hemoglobin, platelets, total cholesterol, triglyceride, low-density lipoprotein (LDL), high-density lipoprotein (HDL), apolipoprotein A, apolipoprotein B, IL-10, IL-13 and TNF-α in the blood were remarkably elevated in cerebral infarction group and plaque group (p<0.05). Cerebral infarction group had notably higher levels of CD147, hemoglobin, triglyceride, apolipoprotein B, IL-10, IL-13 and TNF-α in the blood than plaque group (p<0.05). The plaque score was markedly higher in cerebral infarction group than that in plaque group [(3.27±2.86) points vs. (0.93±1.44) points] (p<0.05). In comparison with control group, plaque group and cerebral infarction group exhibited evidently raised levels of blood ET-1 and CRP (p<0.05). The serum CD147 level was significantly associated with MMP-9 (p=0.003, r=0.616), Gensini score (p=0.006, r=0.656), plaque score (p=0.027, r=0.396), IL-10 (p=0.004, r=0.603), TNF-α (p=0.001, r=0.746) and CRP (p=0.037, r=0.450) in cerebral infarction group. CONCLUSIONS: CD147 level is prominently increased in carotid AS and closely related to inflammatory responses, and CD147 may become a new reference for the prediction and treatment of AS and cerebral infarction.

Long-chain non-coding RNA LINC01554 promotes NGFR expression and inhibits cell proliferation, migration, and invasion in hepatocellular carcinoma by binding to microRNA-3681-3p.

OBJECTIVE: The aim of this study was to analyze the role of LINC01554 in the pathogenesis of hepatocellular carcinoma (HCC) and explore the potential mechanism through which LINC01554 affects the migration and proliferation of HCC cells. PATIENTS AND METHODS: LINC01554 expression in HCC tissues and its link to the prognosis of patients were analyzed by The Cancer Genome Atlas (TCGA) database. Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was carried out to examine LINC01554 levels in 60 cases of HCC clinical tissues and HCC cell lines. Then, LINC01554 overexpression model was constructed using lentivirus in HCC cell lines. HCC proliferation and invasive ability were evaluated through Cell Counting Kit (CCK-8) and transwell tests, respectively. Furthermore, the potential action mechanism of LINC01554 was explored using bioinformatics analysis and in vitro cell experiments. RESULTS: Analysis of the TCGA database revealed that LINC01554 was remarkably under-expressed in HCC tissues. Decreased expression of LINC01554 predicted a poor prognosis for patients. Besides, LINC01554 overexpression markedly blunted the proliferation and migratory capacities of HCC cells. LINC01554 competed with NGFR to bind to microRNA-3681-3p, thereby providing possible mechanisms by which LINC01554 could participate in the progression of HCC. CONCLUSIONS: This study shows for the first time that LINC01554 modulates NGFR expression by binding to microRNA-3681-3p, thereby participating in the progression of HCC.

Pravastatin alleviates oxidative stress and decreases placental trophoblastic cell apoptosis through IL-6/STAT3 signaling pathway in preeclampsia rats.

OBJECTIVE: The aim of this study was to explore the effects of pravastatin on oxidative stress and placental trophoblastic cell apoptosis in preeclampsia rats via the interleukin (IL)-6/signal transducer and activator of transcription 3 (STAT3) signaling pathway. MATERIALS AND METHODS: Experimental rats were randomly assigned into three groups, including control group (C group), model group (M group) and pravastatin group (P group). The rat model of preeclampsia was successfully established. Blood pressure, urinary protein and nitric oxide (NO) as well as oxidative stress indicators in rats were detected at 7, 14 and 21 d, respectively. The content of serum IL-6 was determined via enzyme-linked immunosorbent assay (ELISA). The messenger ribonucleic acid (mRNA) expression of IL-6 in the placenta of rats in each group was detected using quantitative polymerase chain reaction (qPCR). Western blotting (WB) was used to determine the protein expression level of STATs in the placental tissues of rats. In addition, cell counting kit (CCK)-8 assay was conducted to detect the proliferation of rat placental trophoblasts. RESULTS: The content of serum NO was (14.32±2.32) µM in M group, (28.37±3.32) µM in C group and (22.54±3.12) µM in P group, respectively. It was significantly elevated in P group compared with M group (p<0.05). Blood pressure in M group was evidently higher than that in C group at 14 and 21 d (p<0.05). However, P group exhibited distinctly lower blood pressure than M group (p<0.05). No statistically significant differences were observed in the urinary protein of rats among all the three groups at 7 d (p>0.05). At 14 and 21 d, the content of urinary protein in M group was considerably higher than that in C group (p<0.05). However, P group had distinctly lower urinary protein content than M group (p<0.05). Compared with C group, the content of malondialdehyde (MDA) and advanced oxidation protein products (AOPP) rose significantly in M group, whereas the content of superoxide dismutase (SOD) declined remarkably (p<0.05). In comparison with M group, P group exhibited declined MDA and AOPP content and increased SOD content, with statistically significant differences between the two groups (p<0.05). The expression level of serum IL-6 in rats in M group was markedly higher than that in C group (p<0.05). Meanwhile, the expression level of serum IL-6 evidently declined in P group compared with M group (p<0.05). Compared with C group, the protein expressions of phosphorylated STAT1 (p-STAT1) and p-STAT3 were considerably up-regulated in M group (p<0.01). However, they decreased prominently in P group in comparison with M group (p<0.01). C group exhibited a remarkably worse proliferation ability of rat placental trophoblasts than C group (p<0.01). In comparison with M group, the proliferation ability of rat placental trophoblasts was evidently enhanced in P group (p<0.05). Flow cytometry results indicated that the apoptosis of trophoblastic cells increased significantly in M group compared with that in C group (p<0.01). However, it significantly declined in P group in comparison with M group (p<0.05). CONCLUSIONS: Pravastatin can repress the IL-6/STAT3 signaling pathway to alleviate oxidative stress, improve preeclampsia and decrease the apoptosis of placental trophoblastic cells in preeclampsia rats.

Association of genetic ancestry with striatal dopamine D2/D3 receptor availability.

Despite ethnic differences in allele frequencies of variants in dopaminergic genes associated with dopamine D2/D3 receptor availability (D2R), no study to date has investigated the relationship between genetic ancestry and striatal D2R. Here, we show that ancestry-informative markers significantly predict dorsal striatal D2R in 117 healthy ethnically diverse residents of the New York metropolitan area using Positron Emission Tomography (PET) with [11C]raclopride (P<0.0001), while correcting for age, sex, BMI, education, smoking status, and estimated socioeconomic status (ZIP codes). Effects of ethnicity on D2R were not driven by variation in dopaminergic candidate genes. Instead, candidate gene associations with striatal D2R were diminished when correcting for ancestry. These findings imply that future studies investigating D2 receptor genes should covary for genetic ancestry or study homogeneous populations. Moreover, ancestry studies on human neurobiology should control for socioeconomic differences between ethnic groups.

Long-term safety and efficacy of telbivudine in infants born to mothers treated during the second or third trimesters of pregnancy.

Telbivudine, an FDA pregnancy category B drug, has been found to reduce hepatitis B virus (HBV) perinatal transmission with no safety concerns in infants aged up to 1 year. This study evaluated the long-term efficacy and safety of telbivudine in 214 infants born to 210 pregnant women with chronic hepatitis B infection who were treated with telbivudine during pregnancy (weeks 20-32 of gestation). The infants were followed for up to 5 years after birth. The efficacy endpoint was the rate of perinatal transmission, which was established by HBsAg and HBV DNA levels at 7 and 12 months. Safety endpoints included head circumference, weight, height, congenital abnormality and hospitalization rates. In addition, the Denver Developmental Screening Test was performed in 92 randomly selected infants. None of the 214 infants born to these women were infected with HBV, and all had effective serum hepatitis B surface antibody (HBsAb) levels. Compared with Chinese standard values, there were few differences in the infants' mean head circumference, weight, and height values. No birth defects were diagnosed, and the congenital abnormality rate was 0.934%. Serious adverse events requiring hospitalization occurred in 20 infants (9.35%). The qualified Denver Developmental Screening Test rate in 92 infants was 97.82%, which was comparable to a rate of 92% in normal Chinese children. Thus, treatment with telbivudine during the second or third trimesters of pregnancy safely blocked perinatal transmission of HBV. Infants born to telbivudine-treated mothers showed normal growth and development during long-term follow-up of up to 5 years.

Alcohol affects brain functional connectivity and its coupling with behavior: greater effects in male heavy drinkers.

Acute and chronic alcohol exposure significantly affect behavior but the underlying neurobiological mechanisms are still poorly understood. Here, we used functional connectivity density (FCD) mapping to study alcohol-related changes in resting brain activity and their association with behavior. Heavy drinkers (HD, N=16, 16 males) and normal controls (NM, N=24, 14 males) were tested after placebo and after acute alcohol administration. Group comparisons showed that NM had higher FCD in visual and prefrontal cortices, default mode network regions and thalamus, while HD had higher FCD in cerebellum. Acute alcohol significantly increased FCD within the thalamus, impaired cognitive and motor functions, and affected self-reports of mood/drug effects in both groups. Partial least squares regression showed that alcohol-induced changes in mood/drug effects were associated with changes in thalamic FCD in both groups. Disruptions in motor function were associated with increases in cerebellar FCD in NM and thalamus FCD in HD. Alcohol-induced declines in cognitive performance were associated with connectivity increases in visual cortex and thalamus in NM, but in HD, increases in precuneus FCD were associated with improved cognitive performance. Acute alcohol reduced 'neurocognitive coupling', the association between behavioral performance and FCD (indexing brain activity), an effect that was accentuated in HD compared with NM. Findings suggest that reduced cortical connectivity in HD contribute to decline in cognitive abilities associated with heavy alcohol consumption, whereas increased cerebellar connectivity in HD may have compensatory effects on behavioral performance. The results reveal how drinking history alters the association between brain FCD and individual differences in behavioral performance.

Association between striatal dopamine D2/D3 receptors and brain activation during visual attention: effects of sleep deprivation.

Sleep deprivation (SD) disrupts dopamine (DA) signaling and impairs attention. However, the interpretation of these concomitant effects requires a better understanding of dopamine's role in attention processing. Here we test the hypotheses that D2/D3 receptors (D2/D3R) in dorsal and ventral striatum would distinctly regulate the activation of attention regions and that, by decreasing D2/D3, SD would disrupt these associations. We measured striatal D2/D3R using positron emission tomography with [(11)C]raclopride and brain activation to a visual attention (VA) task using 4-Tesla functional magnetic resonance imaging. Fourteen healthy men were studied during rested wakefulness and also during SD. Increased D2/D3R in striatum (caudate, putamen and ventral striatum) were linearly associated with higher thalamic activation. Subjects with higher D2/D3R in caudate relative to ventral striatum had higher activation in superior parietal cortex and ventral precuneus, and those with higher D2/D3R in putamen relative to ventral striatum had higher activation in anterior cingulate. SD impaired the association between striatal D2/D3R and VA-induced thalamic activation, which is essential for alertness. Findings suggest a robust DAergic modulation of cortical activation during the VA task, such that D2/D3R in dorsal striatum counterbalanced the stimulatory influence of D2/D3R in ventral striatum, which was not significantly disrupted by SD. In contrast, SD disrupted thalamic activation, which did not show counterbalanced DAergic modulation but a positive association with D2/D3R in both dorsal and ventral striatum. The counterbalanced dorsal versus ventral striatal DAergic modulation of VA activation mirrors similar findings during sensorimotor processing (Tomasi et al., 2015) suggesting a bidirectional influence in signaling between the dorsal caudate and putamen and the ventral striatum.

Recovery of brain structural abnormalities in morbidly obese patients after bariatric surgery.

BACKGROUND/OBJECTIVES: Obesity-related brain structural abnormalities have been reported extensively, and bariatric surgery (BS) is currently the most effective intervention to produce sustained weight reduction in overtly obese (OB) people. It is unknown whether BS can repair the brain circuitry abnormalities concomitantly with long-term weight loss. SUBJECTS/METHODS: In order to investigate whether BS promotes neuroplastic structural recovery in morbidly OB patients, we quantified fractional anisotropy (FA), mean diffusivity (MD) and gray (GM) and white (WM) matter densities in 15 morbidly OB patients and in 18 normal weight (NW) individuals. OB patients were studied at baseline and also 1 month after laparoscopic sleeve gastrectomy surgery. RESULTS: Two-sample t-test between OB (baseline) and NW groups showed decreased FA values, GM/WM densities and increased MD value in brain regions associated with food intake control (that is, caudate, orbitofrontal cortex, body and genu of corpus callosum) and cognitive-emotion regulation (that is, inferior frontal gyrus, hippocampus, insula, external capsule) (P<0.05, family-wise error correction). Paired t-test in the OB group between before and after surgery showed that BS generated partial neuroplastic structural recovery in the OB group, but the differences had relative less strength and smaller volume (P<0.001). CONCLUSIONS: This study provides the first anatomical evidence for BS-induced acute neuroplastic recovery that might in part mediate the long-term benefit of BS in weight reduction. It also highlights the importance of this line of gut-brain axis research employing the combined BS and neuroimaging model for identifying longitudinal changes in brain structure that correlated with obesity status.

Reduced sleep duration mediates decreases in striatal D2/D3 receptor availability in cocaine abusers.

Neuroimaging studies have documented reduced striatal dopamine D2/D3 receptor (D2/D3R) availability in cocaine abusers, which has been associated with impaired prefrontal activity and vulnerability for relapse. However, the mechanism(s) underlying the decreases in D2/D3R remain poorly understood. Recent studies have shown that sleep deprivation is associated with a downregulation of striatal D2/D3R in healthy volunteers. As cocaine abusers have disrupted sleep patterns, here we investigated whether reduced sleep duration mediates the relationship between cocaine abuse and low striatal D2/D3R availability. We used positron emission tomography with [(11)C]raclopride to measure striatal D2/D3R availability in 24 active cocaine abusers and 21 matched healthy controls, and interviewed them about their daily sleep patterns. Compared with controls, cocaine abusers had shorter sleep duration, went to bed later and reported longer periods of sleep disturbances. In addition, cocaine abusers had reduced striatal D2/D3R availability. Sleep duration predicted striatal D2/D3R availability and statistically mediated the relationship between cocaine abuse and striatal D2/D3R availability. These findings suggest that impaired sleep patterns contribute to the low striatal D2/D3R availability in cocaine abusers. As sleep impairments are similarly observed in other types of substance abusers (for example, alcohol and methamphetamine), this mechanism may also underlie reductions in D2/D3R availability in these groups. The current findings have clinical implications suggesting that interventions to improve sleep patterns in cocaine abusers undergoing detoxification might be beneficial in improving their clinical outcomes.

Caffeine increases striatal dopamine D2/D3 receptor availability in the human brain.

Caffeine, the most widely consumed psychoactive substance in the world, is used to promote wakefulness and enhance alertness. Like other wake-promoting drugs (stimulants and modafinil), caffeine enhances dopamine (DA) signaling in the brain, which it does predominantly by antagonizing adenosine A2A receptors (A2AR). However, it is unclear if caffeine, at the doses consumed by humans, increases DA release or whether it modulates the functions of postsynaptic DA receptors through its interaction with adenosine receptors, which modulate them. We used positron emission tomography and [(11)C]raclopride (DA D2/D3 receptor radioligand sensitive to endogenous DA) to assess if caffeine increased DA release in striatum in 20 healthy controls. Caffeine (300 mg p.o.) significantly increased the availability of D2/D3 receptors in putamen and ventral striatum, but not in caudate, when compared with placebo. In addition, caffeine-induced increases in D2/D3 receptor availability in the ventral striatum were associated with caffeine-induced increases in alertness. Our findings indicate that in the human brain, caffeine, at doses typically consumed, increases the availability of DA D2/D3 receptors, which indicates that caffeine does not increase DA in the striatum for this would have decreased D2/D3 receptor availability. Instead, we interpret our findings to reflect an increase in D2/D3 receptor levels in striatum with caffeine (or changes in affinity). The association between increases in D2/D3 receptor availability in ventral striatum and alertness suggests that caffeine might enhance arousal, in part, by upregulating D2/D3 receptors.

Efficacy and safety of telbivudine treatment: an open-label, prospective study in pregnant women for the prevention of perinatal transmission of hepatitis B virus infection.

We evaluated the efficacy and safety of telbivudine (LdT, 600 mg/day) vs control patients (no treatment) in decreasing vertical transmission of HBV, in HBeAg-positive mothers (HBVDNA >6log(10) copies/mL). HBeAg-positive pregnant women either in the second or third trimester were recruited in a prospective, case-control, open-label study, at the Second Affiliated Hospital of the Southeast University, China (February 2008-December 2010). Efficacy (month 7: HBVDNA (+), HBsAg (+) infants) in either the overall group or the treated group and control group was analysed using student's t-test. Infants were followed for at least 1 year. 362 women received LdT (second trimester n = 257; third trimester n = 105) and 92 were untreated. Before delivery, the mean maternal HBVDNA was 2.73, 2.47, 3.34 and 7.94 log10 copies/mL in the overall, second and third trimester treated and control groups, respectively (P < 0.001). At birth, 11.8% of babies overall (43/365), 13.5% (35/259) of those treated in the second trimester, 7.5% of those treated in the third trimester (8/106) and 20.7% (19/92) of untreated infants were HBsAg positive. At month 7, none of the LdT-treated infant had detectable HBVDNA, while eight infants from control mothers were HBsAg positive. Vertical transmission was 0% in LdT treated and 9.3% (8/86) in the control groups (P < 0.001). No difference in the vertical transmission rate was found in mothers treated in the second or third trimester. LdT treatment was safe for mothers and infants, and no congenital deformities were reported.

Stimulant-induced dopamine increases are markedly blunted in active cocaine abusers.

Dopamine signaling in nucleus accumbens is essential for cocaine reward. Interestingly, imaging studies have reported blunted dopamine increases in striatum (assessed as reduced binding of [(11)C]raclopride to D2/D3 receptors) in detoxified cocaine abusers. Here, we evaluate whether the blunted dopamine response reflected the effects of detoxification and the lack of cocaine-cues during stimulant exposure. For this purpose we studied 62 participants (43 non-detoxified cocaine abusers and 19 controls) using positron emission tomography and [(11)C]raclopride (radioligand sensitive to endogenous dopamine) to measure dopamine increases induced by intravenous methylphenidate and in 24 of the cocaine abusers, we also compared dopamine increases when methylphenidate was administered concomitantly with a cocaine cue-video versus a neutral-video. In controls, methylphenidate increased dopamine in dorsal (effect size 1.4; P<0.001) and ventral striatum (location of accumbens) (effect size 0.89; P<0.001), but in cocaine abusers methylphenidate's effects did not differ from placebo and were similar whether cocaine-cues were present or not. In cocaine abusers despite the markedly attenuated dopaminergic effects, the methylphenidate-induced changes in ventral striatum were associated with intense drug craving. Our findings are consistent with markedly reduced signaling through D2 receptors during intoxication in active cocaine abusers regardless of cues exposure, which might contribute to compulsive drug use.

Herpes zoster infection associated with acute coronary syndrome: a population-based retrospective cohort study.

BACKGROUND: Vasculopathy in varicella zoster virus (VZV) infection and a proposed association between herpes virus infection and atherosclerosis suggest a possible link between VZV infection and vascular thrombosis. OBJECTIVES: To determine the risk of acute coronary syndrome (ACS) associated with herpes zoster infection. METHODS: We used the Taiwan National Health Insurance Research Database to identify 57,958 patients newly diagnosed with herpes zoster between 1999 and 2010; 231,832 patients without herpes zoster were examined as the control group. Both cohorts were followed up until the end of 2010 to measure the incidence of ACS. Cox proportional-hazards regression and Kaplan-Meier analyses were used to measure the hazard ratios (HR) and the cumulative incidences of ACS, respectively. RESULTS: The incidence of ACS was 1·24-fold higher in the herpes zoster group than in the control group [36·8 vs. 29·6 per 10,000 person-years, 95% confidence interval (CI) 1·16-1·33]. After adjusting for age, sex and comorbidities, the HR of ACS for the herpes zoster group compared with the control group was 1·15 (95% CI 1·07-1·24). Analysis by the time lag (≤ 3 months, ≤ 1 year, > 1 year) showed that the incidence of ACS remained significantly higher in the herpes zoster group than in the control group, with an adjusted HR of 1·10 (95% CI 1·02-1·19) after the 1-year follow-up period. The Kaplan-Meier survival curve showed that the risk of ACS was significantly higher in the herpes zoster group than in the control group (P < 0·001). CONCLUSION: Herpes zoster infection is associated with an increased risk of ACS.

Peripheral immunomodulation with ginsenoside Rg1 ameliorates neuroinflammation-induced behavioral deficits in rats.

Neuroinflammatory disturbances have been closely associated with depression and many other neuropsychiatric diseases. Although targeting neuroinflammatory mediators with centrally acting drugs has shown certain promise, its translation is faced with several challenges especially drug delivery and safety concerns. Here, we report that neuroinflammation-induced behavioral abnormality could be effectively attenuated with immunomodulatory agents that need not to gain brain penetration. In a rat model with intracerebral lipopolysaccharide (LPS) challenge, we validated that ginsenoside Rg1 (Rg1), a well-established anti-inflammatory agent, was unable to produce a direct action in the brain. Interestingly, peripherally restricted Rg1 could effectively attenuate the weight loss, anorexic- and depressive-like behavior as well as neurochemical disturbances associated with central LPS challenge. Biochemical assay of neuroimmune mediators in the periphery revealed that Rg1 could mitigate the deregulation of the hypothalamic-pituitary-adrenal axis and selectively blunt the increase in circulating interleukin-6 levels. Furthermore, these peripheral regulatory effects were accompanied by dampened microglial activation, mitigated expression of pro-inflammatory mediators and neurotoxic species in the central compartment. Taken together, our work suggested that targeting the peripheral immune system may serve as a novel therapeutic approach to neuroinflammation-induced neuropsychiatric disorders. Moreover, our findings provided the rationale for employing peripherally active agents like Rg1 to combat mental disturbances.

Effect of combined naltrexone and bupropion therapy on the brain's reactivity to food cues.

OBJECTIVE: The significant weight loss observed with combination naltrexone-sustained release (SR) 32 mg and bupropion SR 360 mg (NB32) therapy is thought to be due, in part, to bupropion stimulation of hypothalamic pro-opiomelanocortin (POMC) neurons, and naltrexone blockade of opioid receptor-mediated POMC autoinhibition, but the neurobiological mechanisms are not fully understood. We assessed changes in brain reactivity to food cues before and after NB32 treatment. METHODS: Forty women (31.1±8.1 years; body mass index: 32.5±3.9) received 4 weeks of NB32 or placebo, and were instructed to maintain their dietary and exercise habits. Functional magnetic resonance imaging responses (analyzed using SPM2 and clusters (>100 pixels)) to a 5-min food video (preparation of the subject's favorite food) and a 5-min neutral video (manipulation of neutral objects) under conditions of mild food deprivation (∼14 h) were assessed before and after treatment. RESULTS: The food cues video induced positive brain activation in visual and prefrontal cortices, insula and subcortical brain regions. The group-by-treatment interaction on regional brain activation was significant and showed that whereas NB32 attenuated the activation in the hypothalamus in response to food cues (P<0.01), it enhanced activation in regions involved in inhibitory control (anterior cingulate), internal awareness (superior frontal, insula, superior parietal) and memory (hippocampal) regions (whole-brain analysis; P<0.05). CONCLUSIONS: Blunting the hypothalamic reactivity to food cues while enhancing the activation of regions involved with self-control and internal awareness by NB32 might underlie its therapeutic benefits in obesity.

Obesity and addiction: neurobiological overlaps.

Drug addiction and obesity appear to share several properties. Both can be defined as disorders in which the saliency of a specific type of reward (food or drug) becomes exaggerated relative to, and at the expense of others rewards. Both drugs and food have powerful reinforcing effects, which are in part mediated by abrupt dopamine increases in the brain reward centres. The abrupt dopamine increases, in vulnerable individuals, can override the brain's homeostatic control mechanisms. These parallels have generated interest in understanding the shared vulnerabilities between addiction and obesity. Predictably, they also engendered a heated debate. Specifically, brain imaging studies are beginning to uncover common features between these two conditions and delineate some of the overlapping brain circuits whose dysfunctions may underlie the observed deficits. The combined results suggest that both obese and drug-addicted individuals suffer from impairments in dopaminergic pathways that regulate neuronal systems associated not only with reward sensitivity and incentive motivation, but also with conditioning, self-control, stress reactivity and interoceptive awareness. In parallel, studies are also delineating differences between them that centre on the key role that peripheral signals involved with homeostatic control exert on food intake. Here, we focus on the shared neurobiological substrates of obesity and addiction.

Is 1 Hz rTMS Always Inhibitory in Healthy Individuals?

1 Hz repetitive Transcranial Magnetic Stimulation (rTMS) is considered to have an inhibitory effect in healthy people because it suppresses the excitability of the motor or visual cortex that is expressed as an increase in the motor or the phosphene threshold (PT), respectively. However, the underlying mechanisms and the brain structures involved in the action of rTMS are still unknown. In this study we used two sessions of simultaneous TMS-functional magnetic resonance imaging (fMRI), one before and one after, 15 minutes of 1Hz rTMS to map changes in brain function associated with the reduction in cortical excitability of the primary visual cortex induced by 1 Hz rTMS, when TMS was applied on the occipital area of healthy volunteers. Two groups were evaluated, one group composed of people that can see phosphenes, and another of those lacking this perception. The inhibitory effect, induced by the 1 Hz rTMS, was observed through the increase of the PT, in the first group, but did not lead to a global reduction in brain activation, instead, showed change in the activation pattern before and after rTMS. Conversely, for the second group, changes in brain activation were observed just in few brain areas, suggesting that the effect of 1 Hz rTMS might not be inhibitory for everyone and that the concept of inhibitory/excitatory effect of rTMS may need to be revised.

Repeat variation in the human PER2 gene as a new genetic marker associated with cocaine addiction and brain dopamine D2 receptor availability.

Low dopamine D2 receptor (D2R) levels in the striatum are consistently reported in cocaine abusers; inter-individual variations in the degree of the decrease suggest a modulating effect of genetic makeup on vulnerability to addiction. The PER2 (Period 2) gene belongs to the clock genes family of circadian regulators; circadian oscillations of PER2 expression in the striatum was modulated by dopamine through D2Rs. Aberrant periodicity of PER2 contributes to the incidence and severity of various brain disorders, including drug addiction. Here we report a newly identified variable number tandem repeat (VNTR) polymorphism in the human PER2 gene (VNTR in the third intron). We found significant differences in the VNTR alleles prevalence across ethnic groups so that the major allele (4 repeats (4R)) is over-represented in non-African population (4R homozygosity is 88%), but not in African Americans (homozygosity 51%). We also detected a biased PER2 genotype distribution among healthy controls and cocaine-addicted individuals. In African Americans, the proportion of 4R/three repeat (3R) carriers in healthy controls is much lower than that in cocaine abusers (23% vs 39%, P=0.004), whereas among non-Africans most 3R/4R heterozygotes are healthy controls (10.5% vs 2.5%, P=0.04). Analysis of striatal D2R availability measured with positron emission tomography and [(11)C]raclopride revealed higher levels of D2R in carriers of 4R/4R genotype (P<0.01). Taken together, these results provide preliminary evidence for the role of the PER2 gene in regulating striatal D2R availability in the human brain and in vulnerability for cocaine addiction.

Positive emotionality is associated with baseline metabolism in orbitofrontal cortex and in regions of the default network.

Positive emotionality (PEM) (personality construct of well-being, achievement/motivation, social and closeness) has been associated with striatal dopamine D2 receptor availability in healthy controls. As striatal D2 receptors modulate activity in orbitofrontal cortex (OFC) and cingulate (brain regions that process natural and drug rewards), we hypothesized that these regions underlie PEM. To test this, we assessed the correlation between baseline brain glucose metabolism (measured with positron emission tomography and [(18)F]fluoro-deoxyglucose) and scores on PEM (obtained from the multidimensional personality questionnaire or MPQ) in healthy controls (n = 47). Statistical parametric mapping (SPM) analyses revealed that PEM was positively correlated (P(c)<0.05, voxel corrected) with metabolism in various cortical regions that included orbitofrontal (Brodman area, BA 11, 47) and cingulate (BA 23, 32) and other frontal (BA 10, 9), parietal (precuneus, BA 40) and temporal (BA 20, 21) regions that overlap with the brain's default mode network (DMN). Correlations with the other two main MPQ personality dimensions (negative emotionality and constraint) were not significant (SPM P(c)<0.05). Our results corroborate an involvement of orbitofrontal and cingulate regions in PEM, which is considered a trait that protects against substance use disorders. As dysfunction of OFC and cingulate is a hallmark of addiction, these findings support a common neural basis underlying protective personality factors and brain dysfunction underlying substance use disorders. In addition, we also uncovered an association between PEM and baseline metabolism in regions from the DMN, which suggests that PEM may relate to global cortical processes that are active during resting conditions (introspection, mind wandering).