Bile Acid and Fibroblast Growth Factor 19 Regulation in Obese Diabetics, and Non-Alcoholic Fatty Liver Disease after Sleeve Gastrectomy. J Clin Med. 2019;8:pii: E815. [PMID: 31181641 PMCID: PMC6616896 DOI: 10.3390/jcm8060815]

Research progress on the relationship between bile acid metabolism and type 2 diabetes mellitus

Bile acids, which are steroid molecules originating from cholesterol and synthesized in the liver, play a pivotal role in regulating glucose metabolism and maintaining energy balance. Upon release into the intestine alongside bile, they activate various nuclear and membrane receptors, influencing crucial processes. These bile acids have emerged as significant contributors to managing type 2 diabetes mellitus, a complex clinical syndrome primarily driven by insulin resistance. Bile acids substantially lower blood glucose levels through multiple pathways: BA-FXR-SHP, BA-FXR-FGFR15/19, BA-TGR5-GLP-1, and BA-TGR5-cAMP. They also impact blood glucose regulation by influencing intestinal flora, endoplasmic reticulum stress, and bitter taste receptors. Collectively, these regulatory mechanisms enhance insulin sensitivity, stimulate insulin secretion, and boost energy expenditure. This review aims to comprehensively explore the interplay between bile acid metabolism and T2DM, focusing on primary regulatory pathways. By examining the latest advancements in our understanding of these interactions, we aim to illuminate potential therapeutic strategies and identify areas for future research. Additionally, this review critically assesses current research limitations to contribute to the effective management of T2DM.

State of art on the mechanisms of laparoscopic sleeve gastrectomy in treating type 2 diabetes mellitus

Obesity and type-2 diabetes mellitus (T2DM) are metabolic disorders. Obesity increases the risk of T2DM, and as obesity is becoming increasingly common, more individuals suffer from T2DM, which poses a considerable burden on health systems. Traditionally, pharmaceutical therapy together with lifestyle changes is used to treat obesity and T2DM to decrease the incidence of comorbidities and all-cause mortality and to increase life expectancy. Bariatric surgery is increasingly replacing other forms of treatment of morbid obesity, especially in patients with refractory obesity, owing to its many benefits including good long-term outcomes and almost no weight regain. The bariatric surgery options have markedly changed recently, and laparoscopic sleeve gastrectomy (LSG) is gradually gaining popularity. LSG has become an effective and safe treatment for type-2 diabetes and morbid obesity, with a high cost-benefit ratio. Here, we review the me-chanism associated with LSG treatment of T2DM, and we discuss clinical studies and animal experiments with regard to gastrointestinal hormones, gut microbiota, bile acids, and adipokines to clarify current treatment modalities for patients with obesity and T2DM.

Bariatric surgery for diabetic comorbidities: A focus on hepatic, cardiac and renal fibrosis

Continuously rising trends in diabetes render this disease spectrum an epidemic proportion worldwide. As the disease progresses, the pathological effects of diabetes may impair the normal function of several vital organs, eventually leading to increase the risk of other diabetic comorbidities with advanced fibrosis such as non-alcoholic fatty liver disease, diabetic cardiomyopathy, and diabetic kidney disease. Currently, lifestyle changes and drug therapies of hypoglycemic and lipid-lowering are effective in improving multi-organ function, but therapeutic efficacy is difficult to maintain due to poor compliance and drug reactions. Bariatric surgery, including sleeve gastrectomy and Roux-en-Y gastric bypass surgery, has shown better results in terms of prognosis for diabetes through long-term follow-up. Moreover, bariatric surgery has significant long-term benefits on the function of the heart, liver, kidneys, and other organs through mechanisms associated with reversal of tissue fibrosis. The aim of this review is to describe the impact of type 2 diabetes mellitus on hepatic, cardiac and renal fibrosis and to summarize the potential mechanisms by which bariatric surgery improves multiple organ function, particularly reversal of fibrosis.

An Updated Perspective on the Dual-Track Model of Enterocyte Fat Metabolism

The small intestinal epithelium has classically been envisioned as a conduit for nutrient absorption, but appreciation is growing for a larger and more dynamic role for enterocytes in lipid metabolism. Considerable gaps remain in our knowledge of this physiology, but it appears that the enterocyte's structural polarization dictates its behavior in fat partitioning, treating fat differently based on its absorption across the apical versus the basolateral membrane. In this review, we synthesize existing data and thought on this dual-track model of enterocyte fat metabolism through the lens of human integrative physiology. The apical track includes the canonical pathway of dietary lipid absorption across the apical brush-border membrane, leading to packaging and secretion of those lipids as chylomicrons. However, this track also reserves a portion of dietary lipid within cytoplasmic lipid droplets for later uses, including the "second-meal effect," which remains poorly understood. At the same time, the enterocyte takes up circulating fats across the basolateral membrane by mechanisms that may include receptor-mediated import of triglyceride-rich lipoproteins or their remnants, local hydrolysis and internalization of free fatty acids, or enterocyte de novo lipogenesis using basolaterally absorbed substrates. The ultimate destinations of basolateral-track fat may include fatty acid oxidation, structural lipid synthesis, storage in cytoplasmic lipid droplets, or ultimate resecretion, although the regulation and purposes of this basolateral track remain mysterious. We propose that the enterocyte integrates lipid flux along both of these tracks in order to calibrate its overall program of lipid metabolism.

Interactive Relationships between Intestinal Flora and Bile Acids

The digestive tract is replete with complex and diverse microbial communities that are important for the regulation of multiple pathophysiological processes in humans and animals, particularly those involved in the maintenance of intestinal homeostasis, immunity, inflammation, and tumorigenesis. The diversity of bile acids is a result of the joint efforts of host and intestinal microflora. There is a bidirectional relationship between the microbial community of the intestinal tract and bile acids in that, while the microbial flora tightly modulates the metabolism and synthesis of bile acids, the bile acid pool and composition affect the diversity and the homeostasis of the intestinal flora. Homeostatic imbalances of bile acid and intestinal flora systems may lead to the development of a variety of diseases, such as inflammatory bowel disease (IBD), colorectal cancer (CRC), hepatocellular carcinoma (HCC), type 2 diabetes (T2DM), and polycystic ovary syndrome (PCOS). The interactions between bile acids and intestinal flora may be (in)directly involved in the pathogenesis of these diseases.

Impact of Metabolic Surgery on Gut Microbiota and Sera Metabolomic Patterns among Patients with Diabetes

Metabolic surgery is a promising treatment for obese individuals with type 2 diabetes mellitus (T2DM), but the mechanism is not completely understood. Current understanding of the underlying ameliorative mechanisms relies on alterations in parameters related to the gastrointestinal hormones, biochemistry, energy absorption, the relative composition of the gut microbiota, and sera metabolites. A total of 13 patients with obesity and T2DM undergoing metabolic surgery treatments were recruited. Systematic changes of critical parameters and the effects and markers after metabolic surgery, in a longitudinal manner (before surgery and three, twelve, and twenty-four months after surgery) were measured. The metabolomics pattern, gut microbiota composition, together with the hormonal and biochemical characterizations, were analyzed. Body weight, body mass index, total cholesterol, triglyceride, fasting glucose level, C-peptide, HbA1c, HOMA-IR, gamma-glutamyltransferase, and des-acyl ghrelin were significantly reduced two years after metabolic surgery. These were closely associated with the changes of sera metabolomics and gut microbiota. Significant negative associations were found between the Eubacterium eligens group and lacosamide glucuronide, UDP-L-arabinose, lanceotoxin A, pipercyclobutanamide B, and hordatine B. Negative associations were identified between Ruminococcaceae UCG-003 and orotidine, and glucose. A positive correlation was found between Enterococcus and glutamic acid, and vindoline. Metabolic surgery showed positive effects on the amelioration of diabetes and metabolic syndromes, which were closely associated with the change of sera metabolomics, the gut microbiota, and other disease-related parameters.

Fibroblast Growth Factor 19 and Fibroblast Growth Factor 21 Regulation in Obese Diabetics, and Non-Alcoholic Fatty Liver Disease after Gastric Bypass

Background: Gastric bypass (GB) is an effective treatment for those who are morbidly obese with coexisting type 2 diabetes mellitus (T2DM) or non-alcoholic fatty liver disease (NAFLD). Fibroblast growth factors (FGFs) are involved in the regulation of energy metabolism. Methods: We investigated the roles of FGF 19, FGF 21, and total bile acid among those with morbidly obese and T2DM undergoing GB. A total of 35 patients were enrolled. Plasma FGF 19, FGF 21, and total bile acid levels were measured before surgery (M0), 3 months (M3), and 12 months (M12) after surgery, while the hepatic steatosis index (HSI) was calculated before and after surgery. Results: Obese patients with T2DM after GB presented with increased serum FGF 19 levels (p = 0.024) and decreased total bile acid (p = 0.01) and FGF 21 levels (p = 0.005). DM complete remitters had a higher FGF 19 level at M3 (p = 0.004) compared with DM non-complete remitters. Fatty liver improvers tended to have lower FGF 21 (p = 0.05) compared with non-improvers at M12. Conclusion: Changes in FGF 19 and FGF 21 play differential roles in DM remission and NAFLD improvement for patients after GB. Early increases in serum FGF 19 levels may predict complete remission of T2DM, while a decline in serum FGF 21 levels may reflect the improvement of NAFLD after GB.

Comprehensive Analysis of the Transcriptome-Wide m6A Methylation Modification Difference in Liver Fibrosis Mice by High-Throughput m6A Sequencing

N6-Methyladenosine (m6A), a unique and common mRNA modification method in eukaryotes, is involved in the occurrence and development of many diseases. Liver fibrosis (LF) is a common response to chronic liver injury and may lead to cirrhosis and even liver cancer. However, the involvement of m6A methylation in the development of LF is still unknown. In this study, we performed a systematic evaluation of hepatic genome-wide m6A modification and mRNA expression by m6A-seq and RNA-seq using LF mice. There were 3,315 genes with significant differential m6A levels, of which 2,498 were hypermethylated and 817 hypomethylated. GO and KEGG analyses illustrated that differentially expressed m6A genes were closely correlated with processes such as the endoplasmic reticulum stress response, PPAR signaling pathway and TGF-β signaling pathway. Moreover, a total of 90 genes had both a significant change in the m6A level and mRNA expression shown by joint analysis of m6A-seq and RNA-seq. Hence, the critical elements of m6A modification, including methyltransferase WTAP, demethylases ALKBH5 and binding proteins YTHDF1 were confirmed by RT-qPCR and Western blot. In an additional cell experiment, we also observed that the decreased expression of WTAP induced the development of LF as a result of promoting hepatic stellate cell (HSC) activation. Therefore, this study revealed unique differential m6A methylation patterns in LF mice and suggested that m6A methylation was associated with the occurrence and course of LF to some extent.

Change of plasma amylin after bariatric surgery challenged by oral glucose is associated with remission of type 2 diabetes mellitus

BACKGROUND

Gastric bypass (GB) and sleeve gastrectomy (SG) were found to achieve different remission rates in the treatment of type 2 diabetes (T2DM). The alteration in several gut hormones after bariatric surgery has been demonstrated to play a key role for T2DM remission. Nevertheless, amylin, one of the diabetes-associated peptides, so far has an undetermined position on T2DM remission after bariatric surgery.

METHODS

Sixty eligible patients with T2DM (GB, 30; SG, 30) were initially enrolled in the hospital-based randomized trial. Twenty patients (GB, 10; SG, 10) who met the inclusion criteria and agreed to undergo 75-g oral glucose tolerance test (OGTT) were recruited. The recruited subjects underwent anthropometric measurements, routine laboratory tests, and 75-g OGTT before and 1 year after bariatric surgery. Enzyme immunoassays for plasma amylin were analyzed.

RESULTS

All subjects that underwent GB and half of those who underwent SG achieved T2DM remission. Plasma amylin levels significantly decreased 60-90 min after OGTT in the GB group (p < 0.05) and 30-60 minutes after OGTT in the SG group (p < 0.05). Significantly decreased plasma amylin levels were observed at 30-90 minutes after OGTT in the noncomplete remitters of the GB group (p < 0.05). Plasma amylin levels initially increased (p < 0.05) within 30 minutes after OGTT and then decreased (p < 0.05) in the next 30-minute interval in the nonremitters of the SG group.

CONCLUSION

Postoral glucose challenge amylin levels could be as one of the parameters to evaluate T2DM remission after bariatric surgery, especially in those after SG.

Cholesterol-binding translocator protein TSPO regulates steatosis and bile acid synthesis in nonalcoholic fatty liver disease

Translocator protein (TSPO, 18 kDa) levels increase in parallel with the evolution of simple steatosis (SS) to nonalcoholic steatohepatitis (NASH) in nonalcoholic fatty liver disease (NAFLD). However, TSPO function in SS and NASH is unknown. Loss of TSPO in hepatocytes in vitro downregulated acetyl-CoA acetyltransferase 2 and increased free cholesterol (FC). FC accumulation induced endoplasmic reticulum stress via IRE1A and protein kinase RNA-like ER kinase/ATF4/CCAAT-enhancer-binding protein homologous protein pathways and autophagy. TSPO deficiency activated cellular adaptive antioxidant protection; this adaptation was lost upon excessive FC accumulation. A TSPO ligand 19-Atriol blocked cholesterol binding and recapitulated many of the alterations seen in TSPO-deficient cells. These data suggest that TSPO deficiency accelerated the progression of SS. In NASH, however, loss of TSPO ameliorated liver fibrosis through downregulation of bile acid synthesis by reducing CYP7A1 and CYP27A1 levels and increasing farnesoid X receptor expression. These studies indicate a dynamic and complex role for TSPO in the evolution of NAFLD.

Changes in fasting bile acid profiles after Roux-en-Y gastric bypass and sleeve gastrectomy

BACKGROUND

Bile acid is an essential factor that plays a role in metabolic regulation, but how bile acid is regulated after Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) remains unclear. This meta-analysis aimed to investigate changes in the levels of fasting bile acids following RYGB and SG.

METHODS

A systematic literature search of the PubMed, EMBASE, Cochrane Library and Web of Science databases through July 2020 was performed in accordance with the Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The concentrations of bile acids were evaluated.

RESULTS

Thirteen studies with 289 patients were included. Our results showed that patients who underwent RYGB had increased levels of fasting total bile acids, primary bile acids, secondary bile acids, conjugated bile acids, and unconjugated bile acids, but no significant differences in all these bile acid levels were observed in patients who underwent SG. Furthermore, 12a-hydroxylated bile acid levels and the 12a-hydroxylated/non-12a-hydroxylated bile acid ratio also increased following RYGB.

CONCLUSION

In this study, we found that fasting bile acid levels, especially 12a-hydroxylated bile acids levels, were increased after RYGB. However, no differences in fasting bile acid levels were observed following SG.

Risk of anemia in morbidly obese patients after bariatric surgery in Taiwan

BACKGROUND

Bariatric surgery is one of most effective long-term treatments for morbid obesity. However, post-bariatric surgery anemia is identified as a common adverse effect and remains a challenge nowadays.

AIM

To estimate the risk of post-bariatric surgery anemia and to stratify the association between age, gender, and types of surgery.

METHODS

This study is a population-based cohort study. We conducted this nationwide study using claims data from National Health Insurance Research Database in Taiwan. There were 4373 morbidly obese patients in this study cohort.

RESULTS

Among patients who were diagnosed with morbid obesity, 2864 received bariatric surgery. All obesity-associated comorbidities decreased in the surgical group. Increasing risk of post-bariatric surgery anemia among obese patients was found by Cox proportional hazards regression [adjusted hazard ratio (HR): 2.36]. Also, we found significantly increasing cumulative incidence rate of anemia among patients receiving bariatric surgery by log-rank test. After adjusting for age and gender, the increasing incidence of post-bariatric surgery anemia was found among women (adjusted HR: 2.48), patients in the 20–29-year-old group (adjusted HR: 3.83), and patients in the 30-64-year-old group (adjusted HR: 2.37). Moreover, malabsorptive and restrictive procedures had significantly higher adjusted HRs, 3.18 and 1.55, respectively.

CONCLUSION

Bariatric surgery give rise to anemia risk among obese patients, specifically in women, young- and middle-aged patients, and patients undergoing malabsorptive procedures in our population-based cohort study in Taiwan.

Role of diet and lifestyle modification in the management of nonalcoholic fatty liver disease and type 2 diabetes

Nonalcoholic fatty liver disease (NAFLD) is considered as the hepatic evidence of insulin resistance which is the hallmark of type 2 diabetes. NAFLD is considered as the risk factor for developing type 2 diabetes and has a high frequency of occurrence in those with existing type 2 diabetes. Compared with patients with only NAFLD or type 2 diabetes, these patients show a poor metabolic profile and increase mortality. Hence, effective treatment strategies are necessary. Here, we review the role of diet and lifestyle modification in the management of NAFLD and type 2 diabetes. Based on the available studies, it has been shown that the addition of any kind of physical activity or exercise is beneficial for patients with both NAFLD and type 2 diabetes. Proper dietary management leads to weight loss are also effective in improving metabolic parameters in patients with both NAFLD and type 2 diabetes. In conclusion, it is clear that increasing physical activity or exercise is effective in improving metabolic parameters in patients who are suffering with both NAFLD and type 2 diabetes.

Minireview: Current status of endoscopic duodenal mucosal resurfacing

Several strategies are being pursued to overcome the alarming pandemics of obesity and type 2 diabetes (T2D). In recent years, duodenal mucosal resurfacing (DMR) has shown its potential to improve glycemic indices. Following animal studies, which demonstrated feasibility and safety, the procedure has been applied in two human studies. The DMR procedure has been considered feasible and safe in humans with a limited occurrence of complications and adverse events. Reductions in glycated haemoglobin, weight, fasting plasma glucose, and alanine transaminase have been proven at different follow-up time-points. The length of the ablation may induce different outcomes, having the patients with long duodenal segment ablated showed greater beneficial effects. The current evidence does not still prove the apparent insulin-sensitizing mechanism explaining the impact of the DMR procedure on hepatic glucose production. However, the initial findings have demonstrated a positive risk-benefit ratio and an effect on the treatment of metabolic diseases, such as T2D. Future studies should clarify the mechanisms underlying the positive effects and durability of the treatment using controlled trial conditions on larger number of patients.

Surgery-Induced Weight Loss and Changes in Hormonally Active Fibroblast Growth Factors: a Systematic Review and Meta-Analysis

This systematic review and meta-analysis was performed to investigate the possible changes of FGF-19 and FGF-21 after bariatric surgery (BS). Electronic databases including PubMed and Scopus were systematically searched up to February 2020 to identify pertinent studies. A total of 25 different studies were included. The overall pooled analysis identified that BS caused a significant increase in FGF-19, but had no significant effect on FGF-21. For FGF-19, this finding was supported in the subgroup analyses. For FGF-21, Roux-en-Y gastric bypass (RYGB) surgery significantly increased FGF-21 levels, whereas, in studies with follow-up duration ≥ 1 year, FGF-21 levels decreased significantly. BS reduces circulating concentration of FGF-19, but might increase FGF-21 after RYGB or decrease FGF-21 after ≥ 1 year.

Do different bariatric surgical procedures influence plasma levels of matrix metalloproteinase-2, -7, and -9 among patients with type 2 diabetes mellitus?

BACKGROUND

Bariatric surgery is an efficient strategy for body weight and type 2 diabetes mellitus (T2DM) management. Abnormal lipid deposition in visceral organs, especially the pancreas and liver, might cause beta-cell dysfunction and insulin resistance. Extracellular matrix (ECM) remodeling allows adipose expansion, and matrix metalloproteinases (MMPs) play essential roles in ECM construction. MMP-2 and MMP-9 are the substrates of MMP-7. Different studies have reported that MMP-2, -7, and -9 increase in patients with obesity and metabolic syndromes or T2DM and are considered biomarkers in obesity and hyperglycemia patients.

AIM

To prospectively investigate whether MMP-2, MMP-7, and MMP-9 differ after two bariatric surgeries: Gastric bypass (GB) and sleeve gastrectomy (SG).

METHODS

We performed GB in 23 and SG in 19 obese patients with T2DM. We measured body weight, waist circumference, body mass index (BMI), and serum concentrations of total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, fasting blood sugar (FBS), hemoglobin A1c (HbA1c), C-peptide, homeostasis model assessments of insulin resistance, and MMP-2, MMP-7, and MMP-9 levels at baseline and at 3, 12, and 24 mo post-operation.

RESULTS

Twenty-three patients aged 44.7 ± 9.7 years underwent GB, and 19 patients aged 40.1 ± 9.1 years underwent SG. In the GB group, BMI decreased from 30.3 ± 3.4 to 24.4 ± 2.4 kg/m2, HbA1c decreased from 9.2% ± 1.5% to 6.7% ± 1.4%, and FBS decreased from 171.6 ± 65.0 mg/dL to 117.7 ± 37.5 mg/dL 2 years post-operation (P < 0.001). However, the MMP-2, MMP-7, and MMP-9 levels pre- and post-GB were similar even 2 years post-operation (P = 0.107, 0.258, and 0.466, respectively). The SG group revealed similar results: BMI decreased from 36.2 ± 5.1 to 26.9 ± 4.7 kg/m2, HbA1c decreased from 7.9% ± 1.7% to 5.8% ± 0.6%, and FBS decreased from 138.3 ± 55.6 mg/dL to 95.1 ± 3.1 mg/dL (P < 0.001). The serum MMP-2, -7, and -9 levels pre- and post-SG were not different (P = 0.083, 0.869, and 0.1, respectively).

CONCLUSION

Improvements in obesity and T2DM induced by bariatric surgery might be the result of MMP-2, -7, or -9 independent pathways.

Changes in post-oral glucose challenge pancreatic polypeptide hormone levels following metabolic surgery: A comparison of gastric bypass and sleeve gastrectomy

BACKGROUND

Pancreatic polypeptide (PP) hormone is a 36-amino-acid peptide released from the pancreas, the serum levels of which have been shown to rise upon food intake. The underlying mechanism for metabolic surgery in the treatment of patients with type 2 diabetes mellitus (T2DM) remains intriguing. We compared post-oral glucose challenge PP levels between patients undergoing laparoscopic gastric bypass (GB) and sleeve gastrectomy (SG) at 1 year after surgery.

METHODS

This hospital-based, prospective study followed up a total of 12 laparoscopic GB and 12 laparoscopic SG patients and evaluated their glucose homeostasis. One year after metabolic surgery, 75-g oral glucose tolerance tests (OGTTs) were performed in the patients in the GB and SG groups and the blood levels of PP were evaluated.

RESULTS

The laparoscopic GB group had stable serum PP levels within 120 min after OGTT; however, the levels were significantly higher in the laparoscopic SG group at 30 min after OGTT. The patients with complete T2DM remission did not exhibit significantly different PP levels at fasting and post-OGTT than those in patients without remission after GB. Similarly, after SG, patients with T2DM remission did not show significantly different PP levels at fasting and post-OGTT than those in patients without T2DM remission.

CONCLUSIONS

No significant difference was found in plasma PP levels after OGTT in T2DM patients that received either GB or SG, or in T2DM remitters or non-remitters 1 year after metabolic surgery.

Short-Term Results Suggest That Sleeved Stomach without Resection Is as Effective as Sleeve Gastrectomy in Improving Glucose Control in Type 2 Diabetes Mellitus Sprague-Dawley Rat Model

Background

Although sleeve gastrectomy results in good weight loss and metabolic improvements, it is an irreversible procedure. Therefore, we attempted to assess the possibility of creating a sleeved stomach without resection. Material and Methods. A total of 22 male Sprague-Dawley rats with type 2 diabetes were randomly assigned into 3 different groups: (1) sleeve gastroplasty with gastric remnant-jejunal anastomosis (SGP, n = 8); (2) sleeve gastrectomy (SG, n = 8); and (3) SHAM (n = 6). Body weight, food intake, fasting blood glucose (FBG), hormonal analysis, and oral glucose tolerance test (OGTT) were performed and measured preoperatively and postoperatively.

Results

During the postoperative period, SGP and SG showed significantly lower food intake and body weight when compared with the preoperative levels, respectively (p value < 0.05). Postoperatively, SGP and SG showed improvements in FBG and glucose tolerance levels compared to their respective preoperative levels (p < 0.05). FBG and glucose tolerance levels did not differ between SGP and SG postoperatively. SG resulted in a reduction in fasting ghrelin levels when compared with the preoperative level (p < 0.05). Fasting insulin levels did not differ preoperatively and postoperatively among all groups. Postoperatively, fasting GLP-1 levels were higher in SGP and SG when compared with the preoperative levels, but no statistical significance was observed. Compared preoperatively, the SGP and SG procedures resulted in a decline in HOMA-IR at postoperative 6th week (p < 0.05).

Conclusion

Our animal experiment suggested that at least in the short term, sleeved stomach without resection resulted in similar weight loss and improved glucose control effects compared to sleeve gastrectomy.

Current status of endoscopic sleeve gastroplasty: An opinion review

Bariatric surgeries have been demonstrated to be safe and effective treatment options for morbid obesity patients, but operative risks and high health care costs limit their clinical application. Endoscopic bariatric therapies are emerging as valuable alternatives for patients with doubts about bariatric surgery or ineligible for it. Endoscopic sleeve gastroplasty (ESG), a relatively novel technique of endoscopic bariatric therapies, has gained standing in the past few years. The safety, feasibility, repeatability, and potential for reversibility of ESG have been proven by multicenter studies. Compared to other weight loss strategies, current evidence demonstrates that ESG offers satisfactory efficacy in weight loss. Even though it is inferior to laparoscopic sleeve gastrectomy, it has lower risks of adverse events than surgical interventions and intragastric balloon within one-year follow-up. Furthermore, ESG may be the ideal weight control strategy for patients who have poor adherence to behavioral interventions. Even so, trends in decreased weight loss effect over time, post-procedure weight regain, post-procedure gut hormone alteration, and possible effects of race and ethnicity on ESG still remain undetermined due to very limited reports and very short follow-ups. Further clinical trials are required to validate and answer these questions.

Weight loss induced by whole grain-rich diet is through a gut microbiota-independent mechanism

The prevalence of overweight and obesity has increased worldwide. Obesity is a well-known risk factor of type 2 diabetes mellitus and cardiovascular disease and raises public health concerns. Many dietary guidelines encourage the replacement of refined grains with whole grains (WGs) to enhance body weight management. Current evidence regarding interrelationships among WGs, body weight, and gut microbiota is limited and inconclusive. In this editorial, we comment on the article by Roager et al published in the recent issue of the Gut 2019; 68(1): 83-93. In the study, obese patients (25 < body mass index < 35 kg/m²) were randomly assigned to receive two 8-wk dietary controlling periods with WGs and refined grain-rich diet. The results showed significantly decreased body weight in the WG group. Either the composition of gut microbiota or short-chain fatty acids, the leading end product of fermentation of non-digestible carbohydrate by gut microbiota, did not differ between the two groups. The study highly indicated that a WG-rich diet reduced body weight independent of gut microbiota. We then raised some plausible mechanisms of how WGs might influence body weight and demonstrated more literature in line with WGs enhance body weight control through a microbiota-independent pathway. Possible mechanisms include: (1) The abundant dietary fiber contents of WGs increase satiety, satiation, energy excretion from stool, and energy expenditure simultaneously decreasing energy absorption and fat storage; (2) The plentiful amount of polyphenols of WGs improve energy expenditure by hampering adipocyte maturation and function; (3) The sufficient magnesium and zinc of WGs guarantee lean body mass growth and decrease fat mass; (4) The effect of WGs on brown adipose tissue is a key component of non-shivering thermogenesis; and (5) The increase of adiponectin by WGs enhances glucose utilization, lipid oxidation, and energy expenditure.

Ultra-Early and Early Changes in Bile Acids and Insulin After Sleeve Gastrectomy Among Obese Patients

BACKGROUND AND OBJECTIVE

In obese patients, sleeve gastrectomy (SG) has shown mixed results on bile acid (BA) values. The aim of our study was to examine the potential ultra-early and early changes of the circulating total BA in relation with the changes of insulin resistance (IR) in obese patients submitted to laparoscopic SG. Materials and Methods: Twenty-four obese subjects were investigated for body mass index (BMI), total fasting BA, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), and leptin before and at 7 and 30 d after SG. Results: After surgery, mean BMI decreased at the first (p < 0.001) and at the second time point (p < 0.001) relative to baseline. Total fasting BA values did not change significantly at 7 d (p = 0.938) and at 30 d (p = 0.289) after SG. No significant changes were found at 7 d (p = 0.194, p = 0.34) and 30 d (p = 0.329, p = 0.151) after surgery regarding fasting insulin and HOMA-IR, respectively. However, a trend of increased total fasting BA and decreased fasting insulin and HOMA- after laparoscopic SG has been found. Negative correlations between total fasting BA and insulin (r = -0.807, p = 0.009), HOMA-IR (r = -0.855, p = 0.014), and blood glucose (r = -0.761, p = 0.047), respectively, were observed at one month after SG. Conclusion: In conclusion, here, we found a lack of significant changes in total fasting BA, insulin, and HOMA-IR ultra-early and early after SG, which precluded us to consider a possible relation between the variations of BA and IR. However, the presence of the tendency for total fasting BA to increase and for insulin and HOMA-IR to decrease, as well as of the negative correlations one month after laparoscopic SG, suggest that this surgery brings about some changes that point towards the existence, and possibly towards the restoration, at least to some extent, of the link between BA and glucose metabolism.

Why Bile Acids Are So Important in Non-Alcoholic Fatty Liver Disease (NAFLD) Progression

Non-alcoholic fatty liver disease (NAFLD) is a complex disease, affecting not just the liver, but also all other organs in the body. Despite an increasing amount of people worldwide developing NAFLD and having it progress to non-alcoholic steatohepatitis (NASH) and potentially cirrhosis, there is still no approved therapy. Therefore, huge efforts are being made to find and develop a successful treatment. One of the special interests is understanding the liver-gut axis and especially the role of bile acids in the progression of NAFLD. Farnesoid X receptor (FXR)-agonists have been approved und used in other liver diseases, such as primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC), and have shown signs of being able to decrease inflammation and potentially steatosis. This review will mainly focus on targets/ligands that play an important role in bile acid metabolism and give an overview of ongoing clinical as well as pre-clinical trials. With the complexity of the issue, we did not aim at giving a complete review, rather highlighting important targets and potential treatments that could be approved for NAFLD/NASH treatment within the next few years.

Impacts of Different Modes of Bariatric Surgery on Plasma Levels of Hepassocin in Patients with Diabetes Mellitus

Background: Hepassocin is a liver-derived protein and its serum concentrations significantly increase in diabetes and fatty liver patients. Hepassocin is also a biomarker for diabetes and fatty liver; therefore, we aimed to investigate the impacts of different types of bariatric surgery on hepassocin plasma levels in obese patients with diabetes, and to determine if hepassocin could be a potential new marker for monitoring the effects of bariatric surgery and a treatment target. Methods: Overall, 12 patients undergoing gastric bypass (GB), 10 patients undergoing sleeve gastrectomy (SG) and 11 patients undergoing duodeno-jejunal bypass with sleeve gastrectomy (DJB-SG) were enrolled. Fasting hepassocin levels were measured at baseline, three, 12, and 24 months after surgery. Results: All the three groups significantly decreased their body mass index, waist-to-hip ratio, a body shape index (ABSI), triglycerides, fasting blood sugar, hemoglobin A1c, C-peptide levels and homeostasis model assessment of insulin resistance 24 months after surgery. There were no significant changes in hepassocin levels, even 24 months after the three surgeries. Hepassocin had a significant negative relationship with the ABSI (p< 0.001) 24 months after the SG. Conclusions: Neither GB, SG, nor DJB-SG altered plasma hepassocin levels in diabetic patients up to 24 months after surgery. The use of hepassocin in clinical settings requires more investigation.