Cognitive improvement after bariatric surgery in obesity: neuronal correlates and underlying mechanisms

超重和肥胖在世界范围内呈上升趋势。这些情况与严重的合并症有关，包括高血压、脂质代谢紊乱、胰岛素抵抗和2型糖尿病，以及睡眠呼吸暂停，所有这些都已经在许多研究中得到了广泛的研究。目前，超重和肥胖对大脑功能和结构的负面影响越来越被认识到。在病态肥胖阶段，旨在减肥的传统疗法通常令人沮丧，因此减肥手术已被证明是一种有前途的替代方法。在这里，食物的供应和摄入受到胃肠系统手术的限制，造成相当大的体重减轻。最初的研究可能会显示出手术后认知能力的改善，比如在单词生成和记忆形成方面。然而，减肥手术对大脑功能和结构的影响，特别是限制性手术与限制性手术和吸附不良手术的影响，仍然不完全清楚。在神经元水平上的影响尚未得到研究（例如，灰质体积的变化以及海马等单个大脑区域的功能和结构连接；奖励系统）。此外，这些改善的机制尚不清楚（例如，关于血管改变，抗炎过程，胰岛素-葡萄糖代谢，或胃肠道其他激素，免疫参数，肠道微生物群）。在当前的项目中，我们旨在回答以下问题：1)与等候名单对照组相比，采用限制性和吸附不良方法的减肥手术是否能改善认知能力？2)这种减肥手术是否会改善大脑灰质和白质的结构和连通性，以及神经活动对中性、高热量和低热量刺激的反应？3)这种减肥手术是否能改善血压、能量和脂质代谢、炎症过程、胃肠激素、免疫参数、肠道微生物群？1)至3)的长期后遗症，以及与限制性减肥手术的比较？这些研究问题的答案将为减肥手术作为临床治疗的评估提供重要的贡献，因为认知功能对生活质量和社会参与至关重要。此外，我们将在肥胖和认知之间的机制联系方面获得杰出的科学见解。

Overweight and obesity are on the rise worldwide. These conditions are linked with severe co-morbidities including hypertension, disturbances in lipid metabolism, insulin resistance and type 2 diabetes mellitus, as well as sleep apnea, all of which have already been extensively studied in a number of studies. Currently, negative effects of overweight and obesity on brain function and structure become increasingly recognized. In the stage of morbid obesity, a conventional therapy aiming at weight loss is usually frustrating, so that bariatric surgery has proven to be a promising alter native. Here, food supply and ingestion is restricted by surgery on the gastrointestinal system, causing considerable loss of weight. First studies could show cognitive improvements after surgery, for example in word production and in memory formation. However, the impact of bariatric surgery , particularly restrictive vs restrictive and maladsorptive approaches, on brain function and structure remains incompletely understood. Effects at the neuronal level have not been studied (for example, changes in gray matter volume and functional and structural connectivity of individual brain regions such as the hippocampus; reward system). Also, the mechanisms underlying these improvements are unclear (for example, with regard to vascular changes, anti-inflammatory processes, insulin -glucose metabolism, or other hormones of the gastro-intestinal tract, immunological parameters, gut micorbiom). With the current project we aim to answer the following questions:1) Does bariatric surgery with a restrictive and maladsorptive approach, compared waiting list control group, improve cognitive performance? 2) Does this bariatric surgery lead to improvements in structure and connectivity of gray and white matter of the brain, and neural activity in response to neutral, high- and low-caloric stimuli? 3) Does this bariatric surgery induce improvements in blood pressure, energy and lipid metabolism, inflammatory processes, gastrointestinal hormones, immunological parameters, gut microbiom? Long-term sequelae of 1) to 3), and comparison with restrictive-only bariatric surgery?The answers to these research questions will provide an important contribution in the evaluation of bariatric surgery as a clinical treatment, as cognitive functions are critical for quality of life and social participation. Moreover, we will gain outstanding scientific insights into the mechanistic link between obesity and cognition.