1.
Glial and neuronal markers in bipolar disorder: A meta-analysis testing S100B and NSE peripheral blood levels.
Bartoli, F, Misiak, B, Crocamo, C, Carrà, G
Progress in neuro-psychopharmacology & biological psychiatry. 2020;:109922
Abstract
S100 calcium-binding protein B (S100B) and neuron-specific enolase (NSE) might be peripheral markers reflecting glia and neuronal abnormalities in subjects with bipolar disorder. We carried out a systematic review and meta-analysis, searching for studies indexed in main electronic databases, to clarify whether S100B and NSE blood levels might be increased in bipolar disorder. Eleven studies met eligibility criteria, with data on S100B levels and/or NSE levels in subjects with bipolar disorder and healthy controls, respectively. Random-effects meta-analysis estimated higher levels of S100B in bipolar disorder (standardized mean difference [SMD] = 0.81; p < .001), with some inconsistency across studies (I2 = 81.7%). Findings were confirmed by relevant sensitivity analyses. Meta-regression analyses did not estimate any effect for tested covariates. On the other hand, no differences in NSE levels between individuals with bipolar disorder and healthy controls were estimated (SMD = -0.32; p = .374), with high heterogeneity across studies (I2 = 89.9%). Meta-regression analyses showed that the effect size was influenced by both mean age (p < .001) and illness duration (p = .001) of subjects with bipolar disorders. Our findings support the hypothesis of a possible role of glial abnormalities in the pathophysiology of bipolar disorder.
2.
Influence of feeding state on neurofunctional differences between individuals who are obese and normal weight: a meta-analysis of neuroimaging studies.
Kennedy, J, Dimitropoulos, A
Appetite. 2014;:103-9
Abstract
Obesity is a complex disorder associated with serious health risks. Examining differences in brain activity between normal weight and obese populations in response to food cues may help researchers and clinicians understand the underlying causes of overeating and obesity and help prevent them. Multiple neuroimaging studies have investigated weight differences in functional activity to food cues but have found varying results. We performed six meta-analyses of functional neuroimaging studies of weight differences in response to food images and isolated differences in processing between normal weight and obese participants. Within this study, 7 papers and 3 sets of unpublished data on functional activation to food images were analyzed using an Activation Likelihood Estimation meta-analytic approach. These analyses also addressed how feeding state impacts functional activity between weight groups. Feeding state affected weight related differences in neurofunctional activity triggered by visual food cues. In the premeal state, greater activation in the amygdala/hippocampus was found in obese participants compared to normal weight participants and, in the postmeal state, obese individuals had greater activation in the caudate and medial prefrontal cortex (MPFC) as compared to normal weight individuals. Regions of the brain associated with caloric evaluation, arousal, and memory were more active in the obese before eating, while less activity was found in an area linked to interoceptive processing. In the postmeal state, greater activity was found in the obese in areas related to risk vs. reward evaluation and reward processing. These findings may help researchers and clinicians understand and treat obesity related behaviors by identifying the altered functional regions that lead to obesity, providing a guide for future research on which neural regions need to be the target of further investigation.
3.
Neural bases of food perception: coordinate-based meta-analyses of neuroimaging studies in multiple modalities.
Huerta, CI, Sarkar, PR, Duong, TQ, Laird, AR, Fox, PT
Obesity (Silver Spring, Md.). 2014;(6):1439-46
Abstract
OBJECTIVE The purpose of this study was to compare the results of the three food-cue paradigms most commonly used for functional neuroimaging studies to determine: i) commonalities and differences in the neural response patterns by paradigm and ii) the relative robustness and reliability of responses to each paradigm. METHODS Functional magnetic resonance imaging studies using standardized stereotactic coordinates to report brain responses to food cues were identified using online databases. Studies were grouped by food-cue modality as: i) tastes (8 studies); ii) odors (8 studies); and, iii) images (11 studies). Activation likelihood estimation was used to identify statistically reliable regional responses within each stimulation paradigm. RESULTS Brain response distributions were distinctly different for the three stimulation modalities, corresponding to known differences in location of the respective primary and associative cortices. Visual stimulation induced the most robust and extensive responses. The left anterior insula was the only brain region reliably responding to all three stimulus categories. CONCLUSIONS These findings suggest visual food-cue paradigm as promising candidate for imaging studies addressing the neural substrate of therapeutic interventions.