LEAP-2, integración funcional tejido específica en el balance energético

Ghrelina es una hormona orexigénica ejerce sus acciones a través del receptor GHSR1a. El descubrimiento de LEAP-2 como ligando endógeno de este receptor, mostrando efectos opuestos a ghrelina en ingesta ha abierto un nuevo campo de estudio como una posible diana terapéutica antiobesidad. En la presente tesis doctoral se intentan dilucidar las acciones de LEAP-2 en la regulación de la homeostasis energética y sus efectos antagonizando ghrelina, determinando los mecanismos fisiológicos responsables de estos efectos. Utilizando modelos preclínicos de ratón se analizó el efecto de LEAP-2 central sobre la termogénesis y metabolismo hepático en diferentes condiciones fisiopatológicas. Con el objetivo de discernir acciones centrales y acciones periféricas de LEAP-2 se realizaron experimentos in vitro con cultivos primarios de tejido adiposo y líneas celulares de hepatocitos humanos. Nuestros resultados indican que LEAP-2 es regulado por el estado nutricional de forma inversa a ghrelina, y que su administración central ejerce importantes acciones en la homeostasis energética del organismo actuando sobre la termogénesis y el metabolismo de ácidos grasos en hígado. Por otra parte, a nivel periférico actúa de manera directa sobre hígado y tejido adiposo. En conclusión, LEAP-2 se posiciona como una hormona contrarreguladora, jugando un papel fundamental en el sistema de ghrelina y podría ser considerada como una nueva diana terapéutica en el tratamiento de la obesidad, MAFLD y otras enfermedades metabólicas

Isolating the Effects of Word’s Emotional Valence on Subsequent Morphosyntactic Processing: An Event-Related Brain Potentials Study

Emotional information significantly affects cognitive processes, as proved by research in the past decades. Recently, emotional effects on language comprehension and, particularly, syntactic processing, have been reported. However, more research is needed, as this is yet very scarce. The present paper focuses on the effects of emotion-laden linguistic material (words) on subsequent morphosyntactic processing, by using Event-Related brain Potentials (ERP). The main aim of this paper is to clarify whether the effects previously reported remain when positive, negative and neutral stimuli are equated in arousal levels and whether they remain long-lasting. In addition, we aimed at testing whether these effects vary as a function of the task performed with the emotion-laden words, to assess their robustness across variations in attention and cognitive load during the processing of the emotional words. In this regard, two different tasks were performed: a reading aloud (RA) task, where participants simply read aloud the words, written in black on white background, and an Emotional Stroop (ES) task, where participants named the colors in which the emotional words were shown. After these words, neutral sentences followed, that had to be evaluated for grammaticality while recording ERPs (50% containing a morphosyntactic anomaly). ERP analyses showed main effects of valence across tasks on the two components reflecting morphosyntactic processing: The Left Anterior Negativity (LAN) is increased by previous emotional words (more by negative than positive) relative to neutral ones, while the P600 is similarly decreased. No interactions between task and valence were found. As a result, an emotion-laden word preceding a sentence can modulate the syntactic processing of the latter, independently of the arousal and processing conditions of the emotional word

Subliminal Priming Effects of Masked Social Hierarchies During a Categorization Task: An Event-Related Brain Potentials Study

published: 07 July 2022Evidence so far shows that status detection increases attentional resources, especially for high hierarchies. However, little is known about the effects of masked social status cues on cognition. Here, we explore the masked priming effects of social status cues during a categorization task. For this purpose, we use Event-Related brain Potentials (ERP) time-locked to the presentation of two types of artworks (Christian, non-Christian) primed by masked social hierarchies sorted into two types (religious, military), and in two ranks (high, low) each. ERP results indicate early attention effects at N1, showing larger amplitudes for the processing of artworks after high and military ranks. Thereafter, the P3a increased for all artworks primed by religious vs. military figures, indicating a relevant role of task demands at this processing stage. Our results remark the automaticity of hierarchy detection and extend previous findings on the effects of social status cues on complex cognitive processes.This work was supported by the MINECO (Ministerio de Economía y Competitividad, PSI2013-43107-P) and Ministerio de Ciencia, Investigación y Universidades (Programa Estatal de Investigación Científica y Técnica de Excelencia, PSI2017-82357-P), Spai

The Automatic but Flexible and Content-Dependent Nature of Syntax

Syntactic processing has often been considered an utmost example of unconscious automatic processing. In this line, it has been demonstrated that masked words containing syntactic anomalies are processed by our brain triggering event related potential (ERP) components similar to the ones triggered by conscious syntactic anomalies, thus supporting the automatic nature of the syntactic processing. Conversely, recent evidence also points out that regardless of the level of awareness, emotional information and other relevant extralinguistic information modulate conscious syntactic processing too. These results are also in line with suggestions that, under certain circumstances, syntactic processing could also be flexible and context-dependent. However, the study of the concomitant automatic but flexible conception of syntactic parsing is very scarce. Hence, to this aim, we examined whether and how masked emotional words (positive, negative, and neutral masked adjectives) containing morphosyntactic anomalies (half of the cases) affect linguistic comprehension of an ongoing unmasked sentence that also can contain a number agreement anomaly between the noun and the verb. ERP components were observed to emotional information (EPN), masked anomalies (LAN and a weak P600), and unmasked ones (LAN/N400 and P600). Furthermore, interactions in the processing of conscious and unconscious morphosyntactic anomalies and between unconscious emotional information and conscious anomalies were detected. The findings support, on the one hand, the automatic nature of syntax, given that syntactic components LAN and P600 were observed to unconscious anomalies. On the other hand, the flexible, permeable, and context-dependent nature of the syntactic processing is also supported, since unconscious information modulated conscious syntactic components. This double nature of syntactic processing is in line with theories of automaticity, suggesting that even unconscious/automatic, syntactic processing is flexible, adaptable, and context-dependent

Plasma concentration of leptin is related to food addiction in gambling disorder: Clinical and neuropsychological implications

Background: Data implicate overlaps in neurobiological pathways involved in appetite regulation and addictive disorders. Despite different neuroendocrine measures having been associated with both gambling disorder (GD) and food addiction (FA), how appetite-regulating hormones may relate to the co-occurrence of both entities remain incompletely understood. Aims: To compare plasma concentrations of ghrelin, leptin, adiponectin, and liver-expressed antimicrobial peptide 2 (LEAP-2) between patients with GD, with and without FA, and to explore the association between circulating hormonal concentrations and neuropsychological and clinical features in individuals with GD and FA. Methods: The sample included 297 patients diagnosed with GD (93.6% males). None of the patients with GD had lifetime diagnosis of an eating disorder. FA was evaluated with the Yale Food Addiction Scale 2.0. All patients were assessed through a semi-structured clinical interview and a psychometric battery including neuropsychological tasks. Blood samples to measure hormonal variables and anthropometric variables were also collected. Results: From the total sample, FA was observed in 23 participants (FA+) (7.7% of the sample, 87% males). When compared participants with and without FA, those with FA+ presented both higher body mass index (BMI) (p < 0.001) and leptin concentrations, after adjusting for BMI (p = 0.013). In patients with FA, leptin concentrations positively correlated with impulsivity, poorer cognitive flexibility, and poorer inhibitory control. Other endocrine measures did not differ between groups. Discussion and conclusions: The present study implicates leptin in co-occurring GD and FA. Among these patients, leptin concentration has been associated with clinical and neuropsychological features, such as impulsivity and cognitive performance in certain domains

How the Emotional Content of Discourse Affects Language Comprehension

Emotion effects on cognition have often been reported. However, only few studies investigated emotional effects on subsequent language processing, and in most cases these effects were induced by non-linguistic stimuli such as films, faces, or pictures. Here, we investigated how a paragraph of positive, negative, or neutral emotional valence affects the processing of a subsequent emotionally neutral sentence, which contained either semantic, syntactic, or no violation, respectively, by means of event-related brain potentials (ERPs). Behavioral data revealed strong effects of emotion; error rates and reaction times increased significantly in sentences preceded by a positive paragraph relative to negative and neutral ones. In ERPs, the N400 to semantic violations was not affected by emotion. In the syntactic experiment, however, clear emotion effects were observed on ERPs. The left anterior negativity (LAN) to syntactic violations, which was not visible in the neutral condition, was present in the negative and positive conditions. This is interpreted as reflecting modulatory effects of prior emotions on syntactic processing, which is discussed in the light of three alternative or complementary explanations based on emotion-induced cognitive styles, working memory, and arousal models. The present effects of emotion on the LAN are especially remarkable considering that syntactic processing has often been regarded as encapsulated and autonomous

Hypothalamic Mitochondrial Dysfunction as a Target in Obesity and Metabolic Disease

Mitochondria are important organelles for the adaptation to energy demand that play a central role in bioenergetics metabolism. The mitochondrial architecture and mitochondrial machinery exhibits a high degree of adaptation in relation to nutrient availability. On the other hand, its disruption markedly affects energy homeostasis. The brain, more specifically the hypothalamus, is the main hub that controls energy homeostasis. Nevertheless, until now, almost all studies in relation to mitochondrial dysfunction and energy metabolism have focused in peripheral tissues like brown adipose tissue, muscle, and pancreas. In this review, we highlight the relevance of the hypothalamus and the influence on mitochondrial machinery in its function as well as its consequences in terms of alterations in both energy and metabolic homeostasis

The sacred and the absurd--an electrophysiological study of counterintuitive ideas (at sentence level).

Religious beliefs are both catchy and durable: they exhibit a high degree of adherence to our cognitive system, given their success of transmission and spreading throughout history. A prominent explanation for religion's cultural success comes from the "MCI hypothesis," according to which religious beliefs are both easy to recall and desirable to transmit because they are minimally counterintuitive (MCI). This hypothesis has been empirically tested at concept and narrative levels by recall measures. However, the neural correlates of MCI concepts remain poorly understood. We used the N400 component of the event-related brain potential as a measure of counterintuitiveness of violations comparing religious and non-religious sentences, both counterintuitive, when presented in isolation. Around 80% in either condition were core-knowledge violations. We found smaller N400 amplitudes for religious as compared to non-religious counterintuitive ideas, suggesting that religious ideas are less semantically anomalous. Moreover, behavioral measures revealed that religious ideas are not readily detected as unacceptable. Finally, systematic analyses of our materials, according to conceptual features proposed in cognitive models of religion, did not reveal any outstanding variable significantly contributing to these differences. Refinements of cognitive models of religion should elucidate which combination of factors renders an anomaly less counterintuitive and thus more suitable for recall and transmission