Obesity status and obesity-associated gut dysbiosis effects on hypothalamic structural covariance.

BACKGROUND: Functional connectivity alterations in the lateral and medial hypothalamic networks have been associated with the development and maintenance of obesity, but the possible impact on the structural properties of these networks remains largely unexplored. Also, obesity-related gut dysbiosis may delineate specific hypothalamic alterations within obese conditions. We aim to assess the effects of obesity, and obesity and gut-dysbiosis on the structural covariance differences in hypothalamic networks, executive functioning, and depressive symptoms. METHODS: Medial (MH) and lateral (LH) hypothalamic structural covariance alterations were identified in 57 subjects with obesity compared to 47 subjects without obesity. Gut dysbiosis in the subjects with obesity was defined by the presence of high (n = 28) and low (n = 29) values in a BMI-associated microbial signature, and posthoc comparisons between these groups were used as a proxy to explore the role of obesity-related gut dysbiosis on the hypothalamic measurements, executive function, and depressive symptoms. RESULTS: Structural covariance alterations between the MH and the striatum, lateral prefrontal, cingulate, insula, and temporal cortices are congruent with previously functional connectivity disruptions in obesity conditions. MH structural covariance decreases encompassed postcentral parietal cortices in the subjects with obesity and gut-dysbiosis, but increases with subcortical nuclei involved in the coding food-related hedonic information in the subjects with obesity without gut-dysbiosis. Alterations for the structural covariance of the LH in the subjects with obesity and gut-dysbiosis encompassed increases with frontolimbic networks, but decreases with the lateral orbitofrontal cortex in the subjects with obesity without gut-dysbiosis. Subjects with obesity and gut dysbiosis showed higher executive dysfunction and depressive symptoms. CONCLUSIONS: Obesity-related gut dysbiosis is linked to specific structural covariance alterations in hypothalamic networks relevant to the integration of somatic-visceral information, and emotion regulation.

Neuroinflammation in obesity: circulating lipopolysaccharide-binding protein associates with brain structure and cognitive performance.

BACKGROUND/OBJECTIVES: Growing evidence implicates neuroinflammation in the pathogenesis of diet-induced obesity and cognitive dysfunction in rodent models. Obesity is associated with reduced white matter integrity and cognitive decline. Circulating lipopolysaccharide binding protein (LBP) concentration is known to be increased in patients with obesity. Here, we aimed to evaluate whether circulating LBP is associated longitudinally with white matter structure and cognitive performance according to obesity status. SUBJECTS/METHODS: This longitudinal study analyzed circulating LBP (ELISA), DTI-metrics (axial diffusivity (L1), fractional anisotropy (FA) and radial diffusivity (RD)) in specific regions of the white matter of 24 consecutive middle-aged obese subjects (13 women) and 20 healthy volunteers (10 women) at baseline and two years later. Digit Span Test (DST) was used as a measure of working memory/short-term verbal memory. RESULTS: Circulating LBP concentration was associated with FA and L1 values of several white matter regions both at baseline and follow-up. The associations remained significant after controlling for age, BMI, fat mass and plasma high sensitivity C-reactive protein. Importantly, the increase in LBP over time impacted negatively on FA and L1 values and on DST performance. CONCLUSIONS: Circulating LBP associates with brain white matter integrity and working memory/short-term verbal memory in both obese and non-obese subjects.

[Schistosomiasis imported by Spanish travelers: clinico-epidemiologic study of 80 cases]. / Esquistosomiasis importada por viajeros españoles: estudio clínico epidemiológico de 80 casos.

BACKGROUND: Swimming in rivers or lakes is a risk activity, in areas where the life cycle of schistosomiasis occurs. This report presents and analyzes the clinical presentation and epidemiological data of 80 Spanish travellers. PATIENTS AND METHODS: Descriptive longitudinal and retrospective study that includes clinicoepidemiological and the laboratory data and imaging diagnosis. Patients were seen at the Section of Tropical Medicine, Hospital Clínic i Provincial, Barcelona. RESULTS: Most patients acquired the infection in the Dogon country of Mall. 25% of them presented with symptoms related to the genital tract. In some groups, 45% of travellers that swam, contracted the infection. The most prevalent species diagnosed was S. haematobium and 10 travellers presented with mixed infections. CONCLUSIONS: The trip to the Dogon country should be considered as "a risk activity". Travellers Advice Clinics should include the subject of swimming in infected waters in their routine counselling. Genital tract localizations were registered for three species of schistosome. The classical clinical presentation of schistosomiasis in the endemic areas differs considerably from that seen in travellers.