Central Modulation of Energy Homeostasis and Cognitive Performance After Bariatric Surgery

The Association of Serum Irisin with Impaired Glucose Before and After Laparoscopic Sleeve Gastrectomy in Obesity

BACKGROUND

To demonstrate the association of irisin levels with impaired glucose before and after laparoscopic sleeve gastrectomy (LSG) in patients with obesity.

METHODS

Thirty-six patients with obesity undergoing LSG were included. We tested the irisin levels before and after LSG and conducted an evaluation of baseline irisin levels with elevated glucose as well as irisin changes with weight loss and its association with glucose control after LSG.

RESULTS

Anthropometric measurements, body fat index, and metabolic parameters were significantly improved in 3 months following LSG (all p < 0.05). Baseline irisin levels were significantly higher in obesity with elevated fasting glucose than that with normal glucose (2.98 [2.37, 3.63] vs. 3.72 [3.06, 5.32], p = 0.031). After adjustment for sex, gender, and body mass index (BMI), obesity with higher irisin levels was prone to have impaired fasting glucose (OR = 2.499, 95% CI = 1.047-5.964). According to receiver operating characteristic curve analysis, the diagnostic accuracy and sensitivity of baseline irisin levels on impaired fasting glucose were 75% and 77.8%. Irisin levels decreased from 3.29 (2.67, 4.43) to 2.82 (2.41, 3.25) ng/mL (p = 0.009) after LSG. The decreases of weight, BMI, and FFA were more in irisin changes group (△irisin ≥ 0.5) than in no irisin changes group (△irisin < 0.5). And △irisin was negatively associated with postprandial glucose (PG) at 3 months after LSG (0.5 h-PG, r =  - 0.478, p = 0.029; 2 h-PG, r =  - 0.406, p = 0.017).

CONCLUSIONS

Elevated baseline irisin levels indicated the impaired glucose in obesity. The decrease of irisin with weight loss provided more evidence for the contribution of serum irisin secretion by fat mass in obesity.

Shp2 suppresses fat accumulation in white adipose tissue by activating Wnt/β‑catenin signaling following vertical sleeve gastrectomy in obese rats with type‑2 diabetes

Adipogenesis and fat accumulation are closely associated with the development of obesity. Sleeve gastrectomy (SG) is an effective treatment for obesity and associated metabolic disorders. Leptin is downregulated after SG and Src homology phosphatase 2 (Shp2) has an important role in leptin signaling. The role of Shp2 in SG and the mechanisms of fat reduction following SG were further investigated in the current study. Sham and SG operations were performed on obese type-2 diabetes model Sprague-Dawley rats. Primary pre-adipocytes were isolated from the inguinal white adipose tissue (ingWAT) of the rats. Shp2 expression in ingWAT pre-adipocytes was silenced using small interfering RNA transfection. Shp2 function was inhibited using the specific inhibitor, SHP099. In addition, Shp2 was overexpressed using lentivirus. Gene and protein expression analysis was performed after adipocyte differentiation. Furthermore, Shp2-overexpressing ingWAT pre-adipocytes treated with the β-catenin inhibitor, PNU-74654, were also used for gene and protein expression analysis. Adipogenic markers, including triglycerides, peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding protein α (Cebpα), adiponectin, fatty acid-binding protein 4 and leptin, were examined. Compared with the sham, triglyceride, leptin, PPARγ and Cebpα levels were significantly reduced in the ingWAT from the SG group. Shp2 expression levels were reduced following leptin treatment. Moreover, genetic analysis demonstrated depot-specific adipogenesis following Shp2 silencing or inhibition in ingWAT pre-adipocytes. Conversely, Shp2 overexpression decreased the expression of adipogenic markers by enhancing β-catenin expression. PNU-74654 treatment abolished the downregulation of adipogenic markers caused by Shp2 overexpression. SG decreased leptin levels in ingWAT, which in turn upregulated Shp2, and Shp2 suppressed fat accumulation and adipogenic differentiation by activating the Wnt/β-catenin signaling pathway. Overall, this may represent a potential mechanism of fat reduction in SG, and Shp2 may serve as a potential therapeutic target for the treatment of obesity and type-2 diabetes.

Obesity and Related Type 2 Diabetes: A Failure of the Autonomic Nervous System Controlling Gastrointestinal Function?

The pandemic spread of obesity and type 2 diabetes is a serious health problem that cannot be contained with common therapies. At present, the most effective therapeutic tool is metabolic surgery, which substantially modifies the gastrointestinal anatomical structure. This review reflects the state of the art research in obesity and type 2 diabetes, describing the probable reason for their spread, how the various brain sectors are involved (with particular emphasis on the role of the vagal system controlling different digestive functions), and the possible mechanisms for the effectiveness of bariatric surgery. According to the writer’s interpretation, the identification of drugs that can modulate the activity of some receptor subunits of the vagal neurons and energy-controlling structures of the central nervous system (CNS), and/or specific physical treatment of cortical areas, could reproduce, non-surgically, the positive effects of metabolic surgery.

Caloric restriction, resting metabolic rate and cognitive performance in Non-obese adults: A post-hoc analysis from CALERIE study

Physical activity (PA) has been proposed as a determinant of cognitive function and is one component of energy balance (EB). EB is the difference between energy intake (EI) and the total daily energy expenditure (TDEE). TDEE is a combination of resting metabolic rate (RMR), thermic effect of food and PA. The potential role of each of these components on cognitive function has not yet been systemically investigated. We aim to evaluate the association between each component of EB on cognition, using baseline and longitudinal data from a clinical trial of caloric restriction (CR). This is a parallel-group, randomized clinical trial comparing two years of 25% CR with two years of ad libitum diet (AL), with 220 healthy volunteers of both sex, aged between 21 and 50 years and initial BMI ≥ 22 kg/m2 and <28 kg/m2. Body weight, fat mass (FM), fat-free mass (FFM), and bone mineral content were evaluated, as well as RMR, TDEE, cognitive performance and baseline energy intake. A 30 min/day of a moderate level on a minimum of 5 days/week was advised as PA measure. Longitudinal analysis demonstrated that the influence of CR in the improvement of cognitive performance was moderated by changes in RMR, suggesting that in individuals submitted to CR, the cognitive performance and the RMR improved proportionally, independently of changes in EI and body mass. EB and homeostasis are crucial to modulate the RMR. Moreover, RMR presents an important influence on cognitive function in individuals submitted to CR in a long term.

Metabolic and Bariatric Surgery for Pediatric Patients With Severe Obesity

Severe obesity affects the health and well-being of millions of children and adolescents in the United States and is widely considered to be an "epidemic within an epidemic" that poses a major public health crisis. Currently, few effective treatments for severe obesity exist. Metabolic and bariatric surgery are existing but underuse treatment options for pediatric patients with severe obesity. Roux-en-Y gastric bypass and vertical sleeve gastrectomy are the most commonly performed metabolic and bariatric procedures in the United States and have been shown to result in sustained short-, mid-, and long-term weight loss, with associated resolution of multiple obesity-related comorbid diseases. Substantial evidence supports the safety and effectiveness of surgical weight loss for children and adolescents, and robust best practice guidelines for these procedures exist.

Roux-en-Y gastric bypass surgery progressively alters radiologic measures of hypothalamic inflammation in obese patients

There is increased interest in whether bariatric surgeries such as Roux-en-Y gastric bypass (RYGB) achieve their profound weight-lowering effects in morbidly obese individuals through the brain. Hypothalamic inflammation is a well-recognized etiologic factor in obesity pathogenesis and so represents a potential target of RYGB, but clinical evidence in support of this is limited. We therefore assessed hypothalamic T2-weighted signal intensities (T2W SI) and fractional anisotropy (FA) values, 2 validated radiologic measures of brain inflammation, in relation to BMI and fat mass, as well as circulating inflammatory (C-reactive protein; CrP) and metabolic markers in a cohort of 27 RYGB patients at baseline and 6 and 12 months after surgery. We found that RYGB progressively increased hypothalamic T2W SI values, while it progressively decreased hypothalamic FA values. Regression analyses further revealed that this could be most strongly linked to plasma CrP levels, which independently predicted hypothalamic FA values when adjusting for age, sex, fat mass, and diabetes diagnosis. These findings suggest that RYGB has a major time-dependent impact on hypothalamic inflammation status, possibly by attenuating peripheral inflammation. They also suggest that hypothalamic FA values may provide a more specific radiologic measure of hypothalamic inflammation than more commonly used T2W SI values.

Neurosurgical issues of bariatric surgery: A systematic review of the literature and principles of diagnosis and treatment

Bariatric surgery is gaining popularity as the treatment of choice of morbid obesity since this condition is constantly increasing over the last decades. Several complications have emerged as the number of surgeries and follow-up data increase. No systematic review of the neurosurgery-related potential complications has been performed to date. Objective of this work is to fill this gap. We reviewed the literature for bariatric surgery-related complications involving the neurosurgical practice. Moreover, we present explicative cases dealing with peri- and post-operative therapeutic precautions. Three pathological mechanisms emerged. The first is related to intracranial pressure alterations and may imply either intracranial hypertension or hypotension syndromes in the operative or post-operative periods. The second is the deficiency of macro- and micro-nutrients which are potential risk factors for neuro- or myelo-encephalopathies, fetal malformations and spine disorders. The third is a dysregulation of both autonomic and endocrine / pituitary control. Neurosurgeons must be aware of the several, multifactorial neurosurgery-related complications of bariatric surgery as their prevalence is likely to be higher in the next few years.

Interventions for the Treatment of Craniopharyngioma-Related Hypothalamic Obesity: A Systematic Review

OBJECTIVE

Craniopharyngiomas (CPs) and their treatment are associated with hypothalamic damage that causes hypothalamic obesity (HO) in 30%-70% of cases. Thus, there is ongoing research regarding tangible solutions for HO, because these patients have unrelenting resistance to basic weight-loss interventions. This review aims to summarize the interventions that are used to treat CP-related HO (CP-HO), including pharmacotherapy and bariatric surgery.

METHODS

The Cochrane Library, EMBASE, and PubMed databases were searched up to June 2017 for relevant reports. Two reviewers conducted independent evaluations of the studies identified.

RESULTS

Eighteen articles were included in the systematic review, with 3 reports describing pharmacotherapy in randomized controlled trials and 15 reports describing bariatric surgery. Although several studies described effective interventions for treating CP-HO, the evidence base was limited by its low quality and our inability to perform a meta-analysis, which was related to a lack of adequate or integrated data.

CONCLUSIONS

Octreotide appears to be a preferred treatment for patients with CP-HO, based on limited data. Gastric bypass surgery may also be suitable for select patients with CP-HO, based on a review of various procedures in this setting. Microsurgical preservation of the hypothalamic structures is mandatory to decrease CP-HO-related morbidity and mortality. Further studies with adequate analytical power and sufficient follow-up are needed to identify effective strategies for CP-HO treatment.

Functional Foods and Lifestyle Approaches for Diabetes Prevention and Management

Functional foods contain biologically active ingredients associated with physiological health benefits for preventing and managing chronic diseases, such as type 2 diabetes mellitus (T2DM). A regular consumption of functional foods may be associated with enhanced anti-oxidant, anti-inflammatory, insulin sensitivity, and anti-cholesterol functions, which are considered integral to prevent and manage T2DM. Components of the Mediterranean diet (MD)-such as fruits, vegetables, oily fish, olive oil, and tree nuts-serve as a model for functional foods based on their natural contents of nutraceuticals, including polyphenols, terpenoids, flavonoids, alkaloids, sterols, pigments, and unsaturated fatty acids. Polyphenols within MD and polyphenol-rich herbs-such as coffee, green tea, black tea, and yerba maté-have shown clinically-meaningful benefits on metabolic and microvascular activities, cholesterol and fasting glucose lowering, and anti-inflammation and anti-oxidation in high-risk and T2DM patients. However, combining exercise with functional food consumption can trigger and augment several metabolic and cardiovascular protective benefits, but it is under-investigated in people with T2DM and bariatric surgery patients. Detecting functional food benefits can now rely on an "omics" biological profiling of individuals' molecular, genetics, transcriptomics, proteomics, and metabolomics, but is under-investigated in multi-component interventions. A personalized approach for preventing and managing T2DM should consider biological and behavioral models, and embed nutrition education as part of lifestyle diabetes prevention studies. Functional foods may provide additional benefits in such an approach.