| 11. |
|
|
| 12. |
- Abdeen, G., et al.
(author)
-
Mechanism Underlying the Weight Loss and Complications of Roux-en-Y Gastric Bypass. Review
- 2016
-
In: Obesity Surgery. - : Springer Science and Business Media LLC. - 0960-8923 .- 1708-0428. ; 26:2, s. 410-421
-
Research review (peer-reviewed)abstract
- Various bariatric surgical procedures are effective at improving health in patients with obesity associated co-morbidities, but the aim of this review is to specifically describe the mechanisms through which Roux-en-Y gastric bypass (RYGB) surgery enables weight loss for obese patients using observations from both human and animal studies. Perhaps most but not all clinicians would agree that the beneficial effects outweigh the harm of RYGB; however, the mechanisms for both the beneficial and deleterious (for example postprandial hypoglycaemia, vitamin deficiency and bone loss) effects are ill understood. The exaggerated release of the satiety gut hormones, such as GLP-1 and PYY, with their central and peripheral effects on food intake has given new insight into the physiological changes that happen after surgery. The initial enthusiasm after the discovery of the role of the gut hormones following RYGB may need to be tempered as the magnitude of the effects of these hormonal responses on weight loss may have been overestimated. The physiological changes after RYGB are unlikely to be due to a single hormone, or single mechanism, but most likely involve complex gut-brain signalling. Understanding the mechanisms involved with the beneficial and deleterious effects of RYGB will speed up the development of effective, cheaper and safer surgical and non-surgical treatments for obesity.
|
|
| 13. |
- Abdeen, G. N., et al.
(author)
-
Sugar Detection Threshold After Laparoscopic Sleeve Gastrectomy in Adolescents
- 2018
-
In: Obesity Surgery. - : Springer Science and Business Media LLC. - 0960-8923 .- 1708-0428. ; 28:5, s. 1302-1307
-
Journal article (peer-reviewed)abstract
- Obesity in young people is one of the most serious public health problems worldwide. Moreover, the mechanisms preventing obese adolescents from losing and maintaining weight loss have been elusive. Laparoscopic sleeve gastrectomy (LSG) is successful at achieving long-term weight loss in patients across all age groups, including children and adolescents. Anecdotal clinical observation as well as evidence in rodents suggests that LSG induces a shift in preference of sugary foods. However, it is not known whether this shift is due to a change in the threshold for gustatory detection of sucrose, or whether LSG induces behavioral change without affecting the gustatory threshold for sugar. The objective of this study was to determine whether adolescents who undergo LSG experience a change in their threshold for detecting sweet taste. We studied the sucrose detection threshold of 14 obese adolescents (age 15.3 +/- 0.5 years, range 12-18) who underwent LSG 2 weeks before surgery and at 12 and 52 weeks after surgery. Matched non-surgical subjects were tested on two occasions 12 weeks apart to control for potential learning of the test that may have confounded the results. Seven sucrose concentrations were used and were tested in eight blocks with each block consisting of a random seven sucrose and seven water stimuli. The subjects were asked to report whether the sample contained water or not after they tasted 15 ml of the fluid for 10 s. The bodyweight of the LSG group decreased from 136.7 +/- 5.4 to 109.6 +/- 5.1 and 86.5 +/- 4.0 kg after 12 and 52 weeks, respectively (p < 0.001). There was no significant difference after surgery in taste detection threshold of patients after LSG (p = 0.60), and no difference was observed comparing the taste detection threshold of the LSG group with the non-surgical controls (p = 0.38). LSG did not affect the taste detection threshold for sucrose, suggesting that the shift in preference for sugary foods may be due to factors other than fundamental changes in taste sensitivity.
|
|
| 14. |
- Abdeen, G. N., et al.
(author)
-
Vertical sleeve gastrectomy in adolescents reduces the appetitive reward value of a sweet and fatty reinforcer in a progressive ratio task
- 2019
-
In: Surgery for Obesity and Related Diseases. - : Elsevier BV. - 1550-7289. ; 15:2, s. 194-199
-
Journal article (peer-reviewed)abstract
- Background: Adolescent obesity is challenging to treat even if good multidisciplinary approaches are started early. Vertical sleeve gastrectomy (VSG) is an effective intervention for long-term weight loss, but the underlying mechanisms that result in reduced calorie intake are controversial. Anecdotal evidence from the clinic and evidence in rodents after VSG suggest a decrease in the reward value of high-calorie dense foods. Objectives: To determine changes in appetitive behavior of candies (high in sugar and fat) after VSG in adolescents with obesity. Setting: University hospital. Methods: Sixteen adolescents with obesity (age 15.3 ±.5 yr) who had VSG and 10 control patients (age 13.8 ±.6 yr) who had not undergone surgery were studied. Both groups completed a progressive ratio task by clicking a computer mouse on a progressive ratio schedule to receive a candy high in sugar and fat. In the task, patients were required to expend an increasing amount of effort to obtain the reinforcer until they reach a breakpoint (measure of the reward value of the reinforcer). The task was performed before VSG and 12 and 52 weeks after VSG. Results: The VSG group's bodyweight decreased from the baseline 136.6 ± 5.1 to 110.9 ± 5.2 to 87.4 ± 3.7 kg after 12 and 52 weeks, respectively (P <.001). The median breakpoint for candies decreased after VSG from the baseline 320 (160–640) to 80 (50–320) to 160 (80–560) after 12 and 52 weeks, respectively (P =.01). Breakpoints for the control patients did not change (480 [160–640] versus 640 [280–640], P =.17). Conclusion: VSG resulted in a reduction in the reward value of a candy, as suggested by the reduced amount of effort adolescents were prepared to expend to obtain the high-sugar and high-fat candy. The effect was most pronounced 12 weeks after surgery but was largely maintained at 1 year. Long-term attenuation of appetitive behavior may be the key to weight loss and weight loss maintenance after VSG in adolescents. © 2018
|
|
| 15. |
- Abdelaal, M., et al.
(author)
-
Morbidity and mortality associated with obesity
- 2017
-
In: Annals of Translational Medicine. - : AME Publishing Company. - 2305-5839 .- 2305-5847. ; 5:7
-
Journal article (peer-reviewed)abstract
- Obesity and its repercussions constitute an important source of morbidity, impaired quality of life and its complications can have a major bearing on life expectancy. The present article summarizes the most important co-morbidities of obesity and their prevalence. Furthermore, it describes classification and grading systems that can be used to assess the individual and combined impact of co-morbid conditions on mortality risk. The literature was screened for assessment tools that can be deployed in the quantification of morbidity and mortality risk in individual patients. Thirteen specific domains have been identified that account for morbidity and mortality in obesity. Cardiovascular disease (CVD) and cancer account for the greatest mortality risk associated with obesity. The King's Criteria and Edmonton Obesity Staging System (EOSS) were identified as useful tools for the detection and monitoring of individual patient mortality risk in obesity care. The stark facts on the complications of obesity should be capitalized on to improve patient management and knowledge and referred to in the wider dissemination of public health messages aimed at improving primary prevention.
|
|
| 16. |
- Abdelaal, M., et al.
(author)
-
Validated Scoring Systems for Predicting Diabetes Remission After Bariatric Surgery
- 2017
-
In: Bariatric Surgical Practice and Patient Care. - : Mary Ann Liebert Inc. - 2168-023X .- 2168-0248. ; 12:4, s. 153-161
-
Journal article (peer-reviewed)abstract
- Background: Metabolic surgery is a new term used to emphasize the metabolic benefits of a variety of bariatric surgery procedures, particularly with relationship to the treatment of type 2 diabetes and its complications. Means by which the likely impact of metabolic surgery on diabetes could be assessed in individual patients would be of clinical value. Methods: Two main scoring systems (ABCD and DiaRem) have been proposed to predict remission of diabetes after metabolic surgery. We present a description of these systems, discuss the sources of differences in their predictive power, and suggest means by which to improve predictive power. Results: ABCD is more predictive in patients with intermediate and poorer scores. Neither score is validated as a means of predicting, which patients will benefit most from the repercussions of improved glycemic control in terms of complications. Conclusion: A composite scoring system derived from ABCD and DiaRem may improve prediction of postoperative remission rates. Such a system should be considered principally as an aid to decision-making. Excessive focus on prediction of long-term remission of type 2 diabetes mellitus should be avoided in favor of identifying which patients may stand to benefit most, even if full clinical remission is not achieved.
|
|
| 17. |
- Abegg, K., et al.
(author)
-
Effect of bariatric surgery combined with medical therapy versus intensive medical therapy or calorie restriction and weight loss on glycemic control in Zucker diabetic fatty rats
- 2015
-
In: American Journal of Physiology-Regulatory Integrative and Comparative Physiology. - : American Physiological Society. - 0363-6119 .- 1522-1490. ; 308:4
-
Journal article (peer-reviewed)abstract
- Bariatric surgery rapidly improves Type 2 diabetes mellitus (T2DM). Our objective was to profile and compare the extent and duration of improved glycemic control following Roux-en-Y gastric (RYGB) bypass surgery and vertical sleeve gastrectomy (SG) and compare against calorie restriction/weight loss and medical combination therapy-based approaches using the Zucker diabetic fatty rat (ZDF) rodent model of advanced T2DM. Male ZDF rats underwent RYGB (n = 15) or SG surgery (n = 10) at 18 wk of age and received postsurgical insulin treatment, as required to maintain mid-light-phase glycemia within a predefined range (10-15 mmol/l). In parallel, other groups of animals underwent sham surgery with ad libitum feeding (n = 6), with body weight (n = 8), or glycemic matching (n = 8) to the RYGB group, using food restriction or a combination of insulin, metformin, and liraglutide, respectively. Both bariatric procedures decreased the daily insulin dose required to maintain mid-light-phase blood glucose levels below 15 mmol/l, compared with those required by body weight or glycemia-matched rats (P < 0.001). No difference was noted between RYGB and SG with regard to initial efficacy. SG was, however, associated with higher food intake, weight regain, and higher insulin requirements vs. RYGB at study end (P < 0.05). Severe hypoglycemia occurred in several rats after RYGB. RYGB and SG significantly improved glycemic control in a rodent model of advanced T2DM. While short-term outcomes are similar, long-term efficacy appears marginally better after RYGB, although this is tempered by the increased risk of hypoglycemia.
|
|
| 18. |
- Al-Najim, Werd, et al.
(author)
-
Food intake and eating behavior after bariatric surgery
- 2018
-
In: Physiological Reviews. - : American Physiological Society. - 0031-9333 .- 1522-1210. ; 98:3, s. 1113-1141
-
Journal article (peer-reviewed)abstract
- Obesity is an escalating global chronic disease. Bariatric surgery is a very efficacious treatment for obesity and its comorbidities. Alterations to gastrointestinal anatomy during bariatric surgery result in neurological and physiological changes affecting hypothalamic signaling, gut hormones, bile acids, and gut microbiota, which coalesce to exert a profound influence on eating behavior. A thorough understanding of the mechanisms underlying eating behavior is essential in the management of patients after bariatric surgery. Studies investigating candidate mechanisms have expanded dramatically in the last decade. Herein we review the proposed mechanisms governing changes in eating behavior, food intake, and body weight after bariatric surgery. Additive or synergistic effects of both conditioned and unconditioned factors likely account for the complete picture of changes in eating behavior. Considered application of strategies designed to support the underlying principles governing changes in eating behavior holds promise as a means of optimizing responses to surgery and long-term outcomes. © 2018 American Physiological Society. All rights reserved.
|
|
| 19. |
- Althukair, Noura K., et al.
(author)
-
The Effects of Sleeve Gastrectomy on the Appetitive Domain of Taste Using the Progressive Ratio Task
- 2024
-
In: OBESITY SURGERY. - 0960-8923 .- 1708-0428.
-
Journal article (peer-reviewed)abstract
- Introduction Sleeve gastrectomy (SG) is an effective treatment for obesity in adolescents. The underlying weight loss mechanism may impact the peripheral and central gustatory system along with reward circuits in the brain. This study aims to assess changes in appetitive behavior in short-, medium-, and long-term follow-up. Methods In this prospective observational study, a total of 8 adolescents with obesity who underwent SG and 9 comparator unoperated participants were studied. Appetitive behaviour towards fat and sweet taste stimuli was assessed using the Progressive Ratio Task (PRT) over a 6 year period. Results Mean body mass index (BMI) of the surgical patients dropped from 51.5 +/- 2.8 kg/m(2) to 31.4 +/- 1.9 and 30.9 +/- 2.3 kg/m(2) at 1 and 6 years follow-up, respectively. (p < 0.001). The median (interquartile range) total rewards earned during the PRT was 6 (5-7) pre-surgery, 5 (3-6) after one year and 4 (2-4) after six years from surgery (p = 0.007). Conclusion SG reduced appetitive behaviour at 1 year with maintained the benefit over 6 years as measured by the progressive ratio task.
|
|
| 20. |
- Arora, Tulika, et al.
(author)
-
Diabetes-associated microbiota in fa/fa rats is modified by Roux-en-Y gastric bypass
- 2017
-
In: Isme Journal. - : Springer Science and Business Media LLC. - 1751-7362 .- 1751-7370. ; 11:9, s. 2035-2046
-
Journal article (peer-reviewed)abstract
- Roux-en-Y gastric bypass (RYGB) and duodenal jejunal bypass (DJB), two different forms of bariatric surgery, are associated with improved glucose tolerance, but it is not clear whether the gut microbiota contributes to this effect. Here we used fa/fa rats as a model of impaired glucose tolerance to investigate whether (i) the microbiota varies between fa/fa and nondiabetic fa/+ rats; (ii) the microbiota of fa/fa rats is affected by RYGB and/or DJB; and (iii) surgically induced microbiota alterations contribute to glucose metabolism. We observed a profound expansion of Firmicutes (specifically, Lactobacillus animalis and Lactobacillus reuteri) in the small intestine of diabetic fa/fa compared with nondiabetic fa/+ rats. RYGB-, but not DJB-, treated fa/fa rats exhibited greater microbiota diversity in the ileum and lower L. animalis and L. reuteri abundance compared with shamoperated fa/fa rats in all intestinal segments, and their microbiota composition resembled that of unoperated fa/+ rats. To investigate the functional role of RYGB-associated microbiota alterations, we transferred microbiota from sham-and RYGB-treated fa/fa rats to germ-free mice. The metabolic phenotype of RYGB-treated rats was not transferred by the transplant of ileal microbiota. In contrast, postprandial peak glucose levels were lower in mice that received cecal microbiota from RYGBversus sham-operated rats. Thus, diabetes-associated microbiota alterations in fa/fa rats can be modified by RYGB, and modifications in the cecal microbiota may partially contribute to improved glucose tolerance after RYGB.
|
|
