Food Intake and Eating Behavior After Bariatric Surgery.

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.

Impact of time-restricted feeding on kidney injury in male rats with experimental metabolic syndrome.

Disruptions to circadian rhythm may be implicated in the pathogenesis of metabolic syndrome (Met-S). For example, eating during an extended period of the day may negatively impact the circadian rhythms governing metabolic control, contributing, therefore, to Met-S and associated end-organ damage. Accordingly, time-restricted eating (TRE)/feeding (TRF) is gaining popularity as a dietary intervention for the treatment and prevention of Met-S. To date, no studies have specifically examined the impact of TRE/TRF on the renal consequences of Met-S. The proposed study seeks to use a model of experimental Met-S-associated kidney disease to address this knowledge gap, disambiguating therein the effects of calorie restriction from the timing of food intake. Spontaneously hypertensive rats will consume a high-fat diet (HFD) for 8 weeks and then be allocated by stratified randomisation according to albuminuria to one of three groups. Rats will have free 24-h access to HFD (Group A), access to HFD during the scheduled hours of darkness (Group B) or access to HFD provided in the form of two rations, one provided during the light phase and one provided during the dark phase, equivalent overall in quantity to that consumed by rats in Group B (Group C). The primary outcome measure will be a change in albuminuria. Changes in food intake, body weight, blood pressure, glucose tolerance, fasting plasma insulin, urinary excretion of C-peptide and renal injury biomarkers, liver and kidney histopathology and inflammation, and fibrosis-related renal gene expression will be assessed as secondary outcomes.

Dietary restriction and medical therapy drives PPARα-regulated improvements in early diabetic kidney disease in male rats.

The attenuation of diabetic kidney disease (DKD) by metabolic surgery is enhanced by pharmacotherapy promoting renal fatty acid oxidation (FAO). Using the Zucker Diabetic Fatty and Zucker Diabetic Sprague Dawley rat models of DKD, we conducted studies to determine if these effects could be replicated with a non-invasive bariatric mimetic intervention. Metabolic control and renal injury were compared in rats undergoing a dietary restriction plus medical therapy protocol (DMT; fenofibrate, liraglutide, metformin, ramipril, and rosuvastatin) and ad libitum-fed controls. The global renal cortical transcriptome and urinary 1H-NMR metabolomic profiles were also compared. Kidney cell type-specific and medication-specific transcriptomic responses were explored through in silico deconvolution. Transcriptomic and metabolomic correlates of improvements in kidney structure were defined using a molecular morphometric approach. The DMT protocol led to ∼20% weight loss, normalized metabolic parameters and was associated with reductions in indices of glomerular and proximal tubular injury. The transcriptomic response to DMT was dominated by changes in fenofibrate- and peroxisome proliferator-activated receptor-α (PPARα)-governed peroxisomal and mitochondrial FAO transcripts localizing to the proximal tubule. DMT induced urinary excretion of PPARα-regulated metabolites involved in nicotinamide metabolism and reversed DKD-associated changes in the urinary excretion of tricarboxylic acid (TCA) cycle intermediates. FAO transcripts and urinary nicotinamide and TCA cycle metabolites were moderately to strongly correlated with improvements in glomerular and proximal tubular injury. Weight loss plus pharmacological PPARα agonism is a promising means of attenuating DKD.

The altered enteroendocrine reportoire following roux-en-Y-gastric bypass as an effector of weight loss and improved glycaemic control.

The alarming rise in obesity and relative lack of pharmacotherapies to treat, what is becoming a global epidemic, has necessitated that an increasing number of bariatric procedures be performed. Several surgical techniques have been developed during the last 50 years and the advent of laparoscopic surgery has increased the safety and efficacy of these procedures. Bariatric surgery is by a substantial margin, the most efficacious means of achieving sustained weight loss maintenance in patients with obesity. Roux-en-Y gastric bypass surgery (RYGB) elicits the most favourable metabolic outcomes with attendant benefits for type 2 diabetes and, cardiovascular disease as well as endocrine disorders and cancers in females. RYGB is the most extensively studied bariatric procedure regarding mechanism of action. In this review we catalogue the multiple alterations in secretion of gut hormones (ghrelin, obestatin, cholecystokinin, GLP-1, PYY, GIP, oxyntomodulin, glicentin and GLP-2) occurring after RYGB and summarise evidence indicating that these changes play a role in the reduction of food intake and improvements in glucose homeostasis.

Early experience with a nutrition and survivorship clinic in esophageal cancer.

Improved cure rates in esophageal cancer care have increased focus on health-related quality of life (HRQL) in survivorship. To optimize recovery after esophagectomy, particularly nutritional well-being, a personalized multidisciplinary survivorship clinic was established at this center. Assessments at 6 and 12 months postoperatively include validated European Organization for the Research and Treatment of Cancer (EORTC) symptom and health-related quality of life (HRQL) questionnaires, functional status review, anthropometry, and biochemical screening for micronutrient deficiencies. 75 patients, at a mean age of 63 years, 84% male, 85% with adenocarcinoma, and 73% receiving multimodal therapy were included. Mean preoperative body mass index (BMI) was 27.5 (4.3) kg m -2. 6- and 12-month assessments were completed by 66 (88%) and 37 (93%) recurrence-free patients, respectively. Mean body weight loss at 6 months was 8.5 ± 6.6% and at 12 months 8.8 ± 7.3%. Of the 12-month cohort, micronutrient deficiency was present in 27 (79.4%) preoperatively and 29 (80.6%) after 1 year (P = 0.727), most commonly iron deficiency (preoperative: 16 [43.2%] and postoperative: 17 [45.9%] patients, P = 0.100). 26 (70.3%) of these patients also had clinically significant dumping syndrome persisting to 12 months after surgery. We describe a novel follow-up support structure for esophageal cancer patients in the first year of survivorship. This may serve as an exemplar model with parallel application across oncological care.

Suppression of enteroendocrine cell glucagon-like peptide (GLP)-1 release by fat-induced small intestinal ketogenesis: a mechanism targeted by Roux-en-Y gastric bypass surgery but not by preoperative very-low-calorie diet.

OBJECTIVE: Food intake normally stimulates release of satiety and insulin-stimulating intestinal hormones, such as glucagon-like peptide (GLP)-1. This response is blunted in obese insulin resistant subjects, but is rapidly restored following Roux-en-Y gastric bypass (RYGB) surgery. We hypothesised this to be a result of the metabolic changes taking place in the small intestinal mucosa following the anatomical rearrangement after RYGB surgery, and aimed at identifying such mechanisms. DESIGN: Jejunal mucosa biopsies from patients undergoing RYGB surgery were retrieved before and after very-low calorie diet, at time of surgery and 6 months postoperatively. Samples were analysed by global protein expression analysis and Western blotting. Biological functionality of these findings was explored in mice and enteroendocrine cells (EECs) primary mouse jejunal cell cultures. RESULTS: The most prominent change found after RYGB was decreased jejunal expression of the rate-limiting ketogenic enzyme mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase (mHMGCS), corroborated by decreased ketone body levels. In mice, prolonged high-fat feeding induced the expression of mHMGCS and functional ketogenesis in jejunum. The effect of ketone bodies on gut peptide secretion in EECs showed a ∼40% inhibition of GLP-1 release compared with baseline. CONCLUSION: Intestinal ketogenesis is induced by high-fat diet and inhibited by RYGB surgery. In cell culture, ketone bodies inhibited GLP-1 release from EECs. Thus, we suggest that this may be a mechanism by which RYGB can remove the inhibitory effect of ketone bodies on EECs, thereby restituting the responsiveness of EECs resulting in increased meal-stimulated levels of GLP-1 after surgery.

The Association Between Kidney Disease and Diabetes Remission in Bariatric Surgery Patients With Type 2 Diabetes.

RATIONALE & OBJECTIVE: The association between bariatric surgery, type 2 diabetes, and chronic kidney disease (CKD) is poorly understood. We studied whether remission of type 2 diabetes induced by bariatric surgery influences markers of kidney disease, if CKD is associated with remission of diabetes after bariatric surgery, and if baseline levels of gut hormones and peptides modify these associations. STUDY DESIGN: Prospective observational study. STUDY PARTICIPANTS: 737 bariatric surgery patients with type 2 diabetes who participated in a multicenter cohort study for up to 5 years. PREDICTORS: Demographics, blood pressure, medications, type of bariatric surgery, anthropometrics, markers of kidney disease, and circulating levels of gut hormones and peptides. OUTCOMES: Estimated glomerular filtration rate (eGFR), urinary albumin excretion, prognostic risk for CKD, and remission of diabetes. ANALYTICAL APPROACH: Linear mixed models for eGFR; generalized linear mixed models with logit link for albuminuria, prognostic risk for CKD, and diabetes remission. RESULTS: Remission of diabetes at 5 years post-bariatric surgery was not independently associated with eGFR but was associated with lower risk for moderate/severe increase in albuminuria (risk ratio, 0.66; 95% CI, 0.48-0.90) and stabilization in prognostic risk for CKD. These findings were modified by baseline ghrelin level. Lower preoperative eGFR and greater prognostic risk for CKD were independently associated with reduced likelihood of diabetes remission. The association with preoperative GFR was modified by C-peptide level. Higher baseline circulating ghrelin level was independently associated with a lower prognostic risk for CKD. LIMITATIONS: A minority of participants had baseline CKD; lack of comparison group; no information on duration of diabetes, other clinical end points, or kidney biopsy results. CONCLUSIONS: Remission of type 2 diabetes 5 years after bariatric surgery was associated with improvements in albuminuria and stabilized prognostic risk for CKD, but not with eGFR. Lower kidney function and greater prognostic risk at the time of bariatric surgery was linked to a lower likelihood of diabetes remission. These results highlight the need to identify the mechanisms through which bariatric surgery may delay the long-term progression of CKD in type 2 diabetes.

Persistent central inflammation and region specific cellular activation accompany depression- and anxiety-like behaviours during the resolution phase of experimental colitis.

Depression and anxiety-related psychological symptoms are increasingly recognised as important co-morbidities in patients with inflammatory bowel disease (IBD). Dextran sulfate sodium (DSS) -induced colitis is an animal model of IBD in which afferent activation of the gut-brain axis can be assessed and explored as a source of behavioural change. Exposure of adult male Wistar rats to DSS (5%) in drinking water induced distal colitis. In parallel to local inflammatory responses in the gut wall, increased expression of IL-6 and iNOS was found in the cerebral cortex and an increase in ventricular volume. Immunoreactivity of immediate early gene FosB/ΔFosB activation was measured as an index of cellular activation and was increased in the nucleus accumbens and dorsal raphe nucleus in acutely colitic animals. Following resolution of the acute colitic response, sustained anhedonia in the saccharin preference test, immobility in the forced swim test, reduced burying behaviour in the marble burying test, and mild signs of anxiety in the elevated plus maze and light/dark box were observed. Central increases in iNOS expression persisted during the recovery phase and mapped to reactive microglia, particularly those found in the parenchyma surrounding circumventricular regions. Evidence of associated nitration was also found. Sustained increases in ventricular volume and reduced T2 magnetic resonance relaxometry time in cortical regions were observed during the recovery period. FosB/ΔFosB activation was evident in the dorsal raphe during recovery. Persistent central inflammation and cellular activation may underpin the emergence of symptoms of depression and anxiety in experimental colitis.

Impact of intentional weight loss on diabetic kidney disease.

Type 2 diabetes mellitus (T2DM) and obesity constitute interwoven pandemics challenging healthcare systems in developed countries, where diabetic kidney disease (DKD) is the most common cause of end-stage renal disease. Obesity accelerates renal functional decline in people with T2DM. Intentional weight loss (IWL) strategies in this population hold promise as a means of arresting DKD progression. In the present paper, we summarize the impact of IWL strategies (stratified by lifestyle intervention, medications, and metabolic surgery) on renal outcomes in obese people with DKD. We reviewed the Medline, EMBASE and Cochrane databases for relevant randomized control trials and observational studies published between August 1, 2018 and April 15, 2019. We found that IWL improves renal outcomes in the setting of DKD and obesity. Rate of progression of DKD slows with IWL, but varying outcome measures among studies makes direct comparison difficult. Furthermore, established means of estimating renal function are imperfect owing to loss of lean muscle mass with IWL strategies. The choice of optimal IWL strategy needs to be individualized; future work should establish the comparative efficacy of IWL strategies in obese people with DKD to better inform such decisions.

Fat free mass is positively associated with hunger and energy intake at extremes of obesity.

Fat mass (FM) has been shown to be negatively associated with energy intake (EI) in lean individuals but in overweight and Class I obese individuals this relationship is poorly understood. Fat free mass (FFM) is positively associated with EI in lean, overweight and Class I obese individuals. To date, the relationships between FFM, FM, hunger and EI have not been investigated in patients with a body mass index (BMI) > 35 kg/m2. The aim of the present study was to examine the associations between FFM, FM, BMI, hunger and EI in individuals with severe (BMI > 35 kg/m2) obesity. In total, 43 subjects (52% male) with a mean (±standard deviation) BMI of 44.5 ±â€¯6.2 kg/m2 were recruited for this cross-sectional analysis. Dual energy x-ray absorptiometry and an ad libitum food buffet were used to measure body composition and EI respectively, and hunger was measured using a visual analogue scale (0-100 mm). BMI (p = 0.02; p < 0.01) and FFM (p < 0.01; p = 0.02), but not FM (p = 0.18; p = 0.71), were positively associated with both EI and pre-buffet hunger, respectively, on multivariable regression using the general linear model. These findings suggest that in extremes of obesity FFM continues to promote hunger and EI, but the inhibitory effect of FM on EI that has been observed in lean populations was not present in this cohort suffering from severe obesity.

Weight Loss, Satiety, and the Postprandial Gut Hormone Response After Esophagectomy: A Prospective Study.

OBJECTIVE: To prospectively characterize changes in body weight, satiety, and postprandial gut hormone profiles following esophagectomy. BACKGROUND: With improved oncologic outcomes in esophageal cancer, there is an increasing focus on functional status and health-related quality of life in survivorship. Early satiety and weight loss are common after esophagectomy, but the pathophysiology of these phenomena remains poorly understood. METHODS: In this prospective study, consecutive patients undergoing esophagectomy with gastric conduit reconstruction were studied preoperatively and at 10 days, 6 weeks, and 3 months postoperatively. Glucagon-like peptide 1 (GLP-1) immunoreactivity of plasma collected immediately before and at 15, 30, 60, 90, 120, 150, and 180 minutes after a standardized 400-kcal mixed meal was determined. Gastrointestinal symptom scores were computed using European Organization for Research and Treatment of Cancer questionnaires. RESULTS: Body weight loss at 6 weeks and 3 months postoperatively among 13 patients undergoing esophagectomy was 11.1 ±â€Š2.3% (P < 0.001) and 16.3 ±â€Š2.2% (P < 0.0001), respectively. Early satiety (P = 0.043), gastrointestinal pain and discomfort (P = 0.01), altered taste (P= 0.006), and diarrhea (P= 0.038) scores increased at 3 months postoperatively. Area under the curve for the satiety gut hormone GLP-1 was significantly increased from 10 days postoperatively (2.4 ±â€Š0.2-fold increase, P < 0.01), and GLP-1 peak increased 3.8 ±â€Š0.6-, 4.7 ±â€Š0.8-, and 4.4 ±â€Š0.5-fold at 10 days, 6 weeks, and 3 months postoperatively (all P < 0.0001). Three months postoperatively, GLP-1 area under the curve was associated with early satiety (P = 0.0002, R = 0.74), eating symptoms (P = 0.007, R = 0.54), and trouble enjoying meals (P = 0.0004, R = 0.73). CONCLUSIONS: After esophagectomy, patients demonstrate an exaggerated postprandial satiety gut hormone response, which may mediate postoperative changes in satiety, body weight, and gastrointestinal quality of life.

The Gut as an Endocrine Organ: Role in the Regulation of Food Intake and Body Weight.

UNLABELLED: Obesity and its related complications remain a major threat to public health. Efforts to reduce the prevalence of obesity are of paramount importance in improving population health. Through these efforts, our appreciation of the role of gut-derived hormones in the management of body weight has evolved and manipulation of this system serves as the basis for our most effective obesity interventions. PURPOSE OF THE REVIEW: We review current understanding of the enteroendocrine regulation of food intake and body weight, focusing on therapies that have successfully embraced the physiology of this system to enable weight loss. RECENT FINDINGS: In addition to the role of gut hormones in the regulation of energy homeostasis, our understanding of the potential influence of enteroendocrine peptides in food reward pathways is evolving. So too is the role of gut derived hormones on energy expenditure. Gut-derived hormones have the ability to alter feeding behavior. Certain obesity therapies already manipulate this system; however, our evolving understanding of the effects of enteroendocrine signals on hedonic aspects of feeding and energy expenditure may be crucial in identifying future obesity therapies.

Reconfiguration of the small intestine and diabetes remitting effects of Roux-en-Y gastric bypass surgery.

PURPOSE OF REVIEW: Alterations in small intestinal physiology are proposed to play a causative role in the beneficial impact of Roux-en-Y gastric bypass on type 2 diabetes mellitus. The present article describes the key proposed mechanisms implicated with an emphasis on some of the newer findings in the field. RECENT FINDINGS: Augmented incretin and diminished anti-incretin effects postsurgery are explored and a model proposed that reconciles the hindgut and foregut hypotheses of improved glycaemic control as being complementary rather than mutually exclusive. Synthesis of recent findings on postbypass changes in intestinal glucose handling then follows. Finally an updated view of the role of distal bile diversion and changes in the microbiota on enteroendocrine signalling is presented. SUMMARY: A series of nonmutually exclusive changes in small intestinal physiology likely make a significant contribution to improved glycaemic control postgastric bypass. Longitudinal data indicate that these effects do not translate into a long-term cure. A number of surgery-induced changes, however, are amenable to device-based and pharmacology-based mimicry, and this is an area for prioritization of future research focus.

Gut Hormone Suppression Increases Food Intake After Esophagectomy With Gastric Conduit Reconstruction.

OBJECTIVES: To characterize the gut hormone profile and determine the effect of satiety gut hormone blockade on food intake in disease-free postesophagectomy patients. BACKGROUND: Improved oncologic outcomes for esophageal cancer have resulted in increased survivorship and a focus on health-related quality of life. Anorexia and early satiety are common, but putative causative factors, in particular the gut-brain hormonal axis, have not been systematically studied. METHODS: In a double-blind, placebo-controlled, randomized crossover study, disease-free patients at least 1 year postresection and gastric conduit reconstruction received either 1 mL 0.9% saline or 1 mL (100 µg) octreotide acetate subcutaneously followed by a standardized ad libitum meal on each of two assessments. Fasting and postprandial plasma glucagon-like peptide 1 (GLP-1), peptide YY (PYY), and ghrelin immunoreactivity were measured. Gut hormone responses and calorie intake postsaline versus octreotide were compared between experimental and control groups. RESULTS: Eighteen subjects [esophagectomy (ES), n = 10, 2.4 ±â€Š0.75 years postresection; and unoperated control subjects, n = 8] were studied. ES demonstrated significant weight loss at 3, 6, 12, and 24 months postoperatively (all P < 0.05). Ghrelin levels were similar (P = 0.58) for both groups, but postprandial GLP-1 and PYY responses were significantly (P < 0.001) greater among ES as compared with controls. After octreotide, ad libitum calorie intake increased among ES (1.5 ±â€Š0.2 fold-change, P = 0.02) but not controls (1.1 ±â€Š0.1 fold-change, P = 0.30). CONCLUSIONS: ES demonstrated an exaggerated postprandial satiety gut hormone response that was attenuated by octreotide, thus identifying a potential therapeutic target to modulate in the ES patient with early satiety.

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.

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.

Weight loss interventions and progression of diabetic kidney disease.

Progressive renal impairment (diabetic kidney disease (DKD)) occurs in upwards of 40 % of patients with obesity and type 2 diabetes mellitus (T2DM) and is a cause of significant morbidity and mortality. Means of attenuating the progression of DKD focus on amelioration of risk factors. Visceral obesity is implicated as a causative agent in impaired metabolic and cardiovascular control in T2DM, and various approaches primarily targeting weight have been examined for their impact on markers of renal injury and dysfunction in DKD. The current report summarises the evidence base for the impact of surgical, lifestyle and pharmacological approaches to weight loss on renal end points in DKD. The potential for a threshold of weight loss more readily achievable by surgical intervention to be a prerequisite for renal improvement is highlighted. Comparing efficacious non-surgical weight loss strategies with surgical strategies in appropriately powered and controlled prospective studies is a priority for the field.

Cardiovascular, renal and overall health outcomes after bariatric surgery.

Obesity is associated with significant increases in morbidity and mortality secondary, in part, to the increased burden of cardiovascular and renal diseases. Currently, bariatric surgery represents an important component of intensive approaches to the treatment of chronic and complex obesity. The efficacy of bariatric surgery extends beyond its ability to support significant and sustainable reductions in bodyweight to improvements in metabolic and cardiovascular health which are proposed to occur, in part, via weight loss-independent physiological changes. This report summarises the concept of cardiovascular and renal diseases as important constituent aspects of obese morbidity that contribute to overall impairments in health and lifespan. It furthermore describes the key features of bariatric surgical interventions, the evidence base for their beneficial effect on cardiovascular and renal diseases, and lastly provides some perspectives on the mechanisms involved.

IHG-1 must be localised to mitochondria to decrease Smad7 expression and amplify TGF-ß1-induced fibrotic responses.

TGF-ß1 is a prototypic profibrotic cytokine and major driver of fibrosis in the kidney and other organs. Induced in high glucose-1 (IHG-1) is a mitochondrial protein which we have recently reported to be associated with renal disease. IHG-1 amplifies responses to TGF-ß1 and regulates mitochondrial biogenesis by stabilising the transcriptional co-activator peroxisome proliferator-activated receptor gamma coactivator-1-alpha. Here we report that the mitochondrial localisation of IHG-1 is pivotal in the amplification of TGF-ß1 signalling. We demonstrate that IHG-1 expression is associated with repression of the endogenous TGF-ß1 inhibitor Smad7. Intriguingly, expression of a non-mitochondrial deletion mutant of IHG-1 (Δmts-IHG-1) repressed TGF-ß1 fibrotic signalling in renal epithelial cells. In cells expressing Δmts-IHG-1 fibrotic responses including CCN2/connective tissue growth factor, fibronectin and jagged-1 expression were reduced following stimulation with TGF-ß1. Δmts-IHG-1 modulation of TGF-ß1 signalling was associated with increased Smad7 protein expression. Δmts-IHG-1 modulated TGF-ß1 activity by increasing Smad7 protein expression as it failed to inhibit TGF-ß1 transcriptional responses when endogenous Smad7 expression was knocked down. These data indicate that mitochondria modulate TGF-ß1 signal transduction and that IHG-1 is a key player in this modulation.

Bariatric surgery and microvascular complications of type 2 diabetes mellitus.

Metabolic dysregulation is the defining characteristic of type 2 diabetes mellitus (T2DM) and can give rise to microvascular complications, specifically retinopathy, nephropathy and neuropathy. Pharmacological targeting of risk factors for microvascular complications can yield therapeutic gains, particularly in relation to retinopathy and nephropathy. Bariatric surgery is superior to intensified pharmacotherapy in relation to glycaemic control and can remediate dyslipidaemia and hypertension. Consequently, evidence of the effect of bariatric surgery on microvascular complications is now emerging in the literature. Examination of the recent published evidence base (covering the period 2011-2014) on the effects of bariatric surgery on microvascular complications reveals further evidence supportive of the efficacy of bariatric surgery in preventing the incidence and progression of albuminuria and arresting renal functional decline. Data on retinopathy are more ambivalent potentially representing the potential in some cases for a degree of surgery associated reactive hypoglycaemia to detract from the benefits of amelioration of hyperglycaemia. A significant gap in the literature remains in relation to the effects of surgery on diabetic neuropathy. Overall, there is a pressing need for prospective randomised controlled trials examining long-term microvascular outcomes following bariatric surgery in patients with T2DM.