Evidence for altered control of glucose disposal after total colectomy

Mechanisms by which sheep milk consumption ameliorates insulin resistance in high-fat diet-fed mice

Sheep milk is rich in fat, protein, vitamins and minerals and is also one of the most important sources of natural bioactives. Several biopeptides in sheep milk have been reported to possess antibacterial, antiviral and anti-inflammatory properties, and they may prevent type 2 diabetes (T2D), disease and cancer. However, the precise mechanism(s) underlying the protective role of sheep milk against T2D development remains unclear. Therefore, in the current study, we investigated the effect of sheep milk on insulin resistance and glucose intolerance in high-fat diet (HFD)-fed mice, by conducting intraperitoneal glucose tolerance tests, metabolic cage studies, genomic sequencing, polymerase chain reaction, and biochemical assays. Hyperinsulinemic-euglycemic clamp-based experiments revealed that mice consuming sheep milk exhibited lower hepatic glucose production than mice in the control group. These findings further elucidate the mechanism by which dietary supplementation with sheep milk alleviates HFD-induced systemic glucose intolerance.

Differences in intestinal microbiota profiling after upper and lower gastrointestinal surgery

BACKGROUND

We aimed to investigate the long-term effects of metabolic profiles and microbiota status in patients after upper gastrointestinal (GI) surgery and lower GI surgery and compared them with a control group.

METHODS

In this cross-sectional study, we analyzed the occurrence of metabolic syndrome (MS) in 10 patients who underwent curative total gastrectomy with Roux-en-Y esophagojejunostomy (RYEJ) anastomosis, 11 patients who underwent curative partial colectomy with right hemicolectomy (RH), and 33 age- and sex-matched controls. Fecal samples were also analyzed by a next-generation sequencing method.

RESULTS

Compared with the control group, the occurrence of MS was significantly lower among patients who underwent total gastrectomy with RYEJ than the controls over the long-term follow-up (>8 years; p < 0.05). Patients who received RH only had a trend of higher serum fasting glucose (p = 0.10). The diversity of the gut microbiota significantly decreased after RH in comparison with the control group and RYEJ group, respectively (p < 0.05). Principal component analysis revealed significant differences between the control, RYEJ, and RH groups (p < 0.001). At the genus level, the ratio of Prevotella to Bacteroides (P/B) was significantly higher in the RYEJ group than in the control group, whereas the P/B ratio was significantly lower in the RH group than in the control group (p < 0.05).

CONCLUSION

Early gastric cancer patients who received total gastrectomy with RYEJ had a lower occurrence of MS than the controls, while early colorectal cancer patients who received RH were associated with a higher serum fasting glucose than the controls during long-term follow-up. In parallel with the metabolic differences, the P/B ratio was also significantly altered in patients after upper and lower GI surgery.

The long term microbiota and metabolic status in patients with colorectal cancer after curative colon surgery

Whether there are subsequent changes of metabolic profiles and microbiota status after partial colectomy remains unknown. We evaluated and compared long-term effects of microbiota status and metabolic profiles in early colorectal cancer (CRC) patients after curative colectomy to the controls. In this cross-sectional study, we analyzed metabolic syndrome occurrence in 165 patients after curative partial colectomy with right hemicolectomy (RH) or low anterior resection (LAR) and 333 age-sex matched controls. Fecal samples from some of those with RH, LAR, and controls were analyzed by next-generation sequencing method. The occurrences of metabolic syndrome were significantly higher in patients after RH, but not LAR, when compared with the controls over the long term (> 5 years) follow-up (P = 0.020). Compared with control group, RH group showed lower bacterial diversity (P = 0.007), whereas LAR group showed significantly higher bacterial diversity at the genera level (P = 0.016). Compared with the control group, the principal component analysis revealed significant differences in bacterial genera abundance after RH and LAR (P < 0.001). Furthermore, the Firmicutes to Bacteroidetes ratio was significantly lower in the RH group than the control group (22.0% versus 49.4%, P < 0.05). In conclusion, early CRC patients after RH but not LAR were associated with a higher occurrence of metabolic syndrome than the controls during long-term follow-up. In parallel with metabolic change, patients with RH showed dysbiosis with a tendency to decreased richness and a significant decrease in the diversity of gut microbiota.

Metformin-related colonic glucose uptake; potential role for increasing glucose disposal?--A retrospective analysis of (18)F-FDG uptake in the colon on PET-CT

AIM

The use of metformin has been associated with diffusely increased colonic (18)F-fluorodeoxyglucose ((18)F-FDG) uptake. Interestingly, metformin use is associated with moderate weight loss. It could be hypothesized that increased colonic glucose disposal is related to this weight loss. It is unknown whether other factors influence (18)F-FDG uptake in the colon. The aim of this study was to retrospectively assess independent determinants of colonic (18)F-FDG uptake.

METHODS

We retrospectively analysed 270 (18)F-FDG PET-CTs which were made for diagnostic purposes. Colonic (18)F-FDG uptake was assessed using a 4-point scale using the liver as a reference (1; lower, 2; similar, 3; moderately higher than hepatic activity, 4; intense diffuse increased uptake). Determinants of (18)F-FDG uptake in the colon were assessed using forward logistic regression (i.e., grade 1&2 vs 3&4).

RESULTS

The patients had a mean age of 60.2±14.8 years, a BMI of 25.8±5.2kg/m(2) and 52% were female. Most patients had a grade 2 (44%) or grade 3 (39%) (18)F-FDG uptake in the colon. Diabetes mellitus type 2 was observed in 14% of the patients. In total, 5% of the patients used insulin, 12% used metformin and 5% used sulfonylurea derivatives (SU). While there seemed to be an effect of SU on (18)F-FDG uptake in the ileum [OR 3.6 (95% CI: 1.3-33.1), p=0.03], metformin was the only drug associated with (18)F-FDG uptake for both the whole colon [OR 10.0 (95% CI: 2.9-34.7), p<0.001] and all individual segments.

CONCLUSION

Metformin use is an independent determinant of increased colonic (18)F-FDG uptake, suggesting a potential role for increasing colonic glucose disposal.

Survival and nutritional dependence on home parenteral nutrition: Three decades of experience from a single referral centre

BACKGROUND

Home parenteral nutrition (HPN) is the mainstay of treatment for patients with Type 3 intestinal failure (IF), however long term data on mortality and nutritional outcomes are limited.

OBJECTIVES

To assess the long-term survival and requirements for ongoing HPN in patients receiving treatment at a UK national referral centre for intestinal failure.

METHODS

Patients with IF who received HPN for more than 3 months at this Intestinal Failure Unit between 1978 and 2011 had their clinical records reviewed. SPSS 20 was utilised to perform Cox regression analysis and generate Kaplan Meier curves, with the aim of identifying factors associated with death and the continued need for HPN.

RESULTS

Case notes from 545 patients were reviewed. Overall survival (OS) in patients without malignancy at commencement of IF was 93%, 71%, 59% and 28% at 1, 5, 10 and 20 years after starting treatment. Crohn's disease, mesenteric ischaemia and chronic intestinal pseudo-obstruction were associated with a better OS than scleroderma and radiation enteritis on multivariate analysis. Older age at onset of IF was associated with poor OS, while shorter small bowel length or central line sepsis was not. 15% (25/170) of deaths were due to complications of HPN (central line sepsis = 10, IF-associated liver disease = 15). Continued HPN dependence in survivors was 83%, 63%, 59% and 53% at 1, 5, 10 and 15 years, respectively. Among the 153 patients without malignancy who achieved nutritional independence from HPN, 77 (50.3%) did so after surgical reconstruction of the alimentary tract (HPN duration mean 19 months, range 3-126 months). 76 patients (49.7%) weaned from HPN without undergoing surgical reconstruction.

CONCLUSION

This is the largest reported data set on long-term survival and dependence on HPN and will inform the indications, benefits and risks of treatment in disease specific groups. A significant proportion of patients achieved nutritional autonomy without surgical intervention.

Hypoglycemia-like symptoms after restorative proctocolectomy for UC: a preliminary study

This study was conducted to explore the hypoglycemia-like symptoms sometimes noted after proctocolectomy for ulcerative colitis. Eighty-three patients who underwent restorative proctocolectomy at least 1 year before December 2001 (staged procedure, n = 50; one-staged procedure, n = 33) were requested to answer three questionnaires at the stage of temporary diverting ileostomy and/or after completion of the operation (after stoma closure). The questionnaires evaluated the presence of 18 items of hypoglycemia-like symptoms, subject recognition of the cause, and whether the symptoms were improved after eating or drinking. Seven subjects (14%) experienced at least one of the three items considered to be specific symptoms of hypoglycemia ("cold sweats," "trembling of hands," and "extreme desire for sweets") at the stage of temporary ileostomy. Ten (20%) and 9 (27.3%) subjects experienced those specific symptoms at the stage after completion of the operation by staged procedure and by one-staged procedure, respectively. There was no significant difference between the stages. Hypoglycemia-like symptoms were found to be experienced in a considerable number of patients after proctocolectomy for ulcerative colitis.

Recent advances in the management of intestinal failure-associated liver disease

PURPOSE OF REVIEW

To summarize the current management of intestinal failure-associated liver disease (IFALD) by reviewing recent advances in our understanding of the condition and the effects of different therapeutic approaches.

RECENT FINDINGS

The importance of gastrointestinal length and continuity in the aetiology and treatment of IFALD has been demonstrated in both retrospective and interventional cohorts. A mechanism for the cholestatic effect of soy-based lipid has been described, and the clinical use of alternative lipid sources has demonstrated benefit. Prevention of IFALD has been shown with the use of erythromycin in neonates, and reversal of established IFALD has been demonstrated with isolated intestinal transplantation.

SUMMARY

A greater understanding of the mechanisms of IFALD has led to promising interventions to prevent and treat the condition. Other possible therapeutic targets require more formal evaluation, and further work is required to develop noninvasive tools for the assessment and prognosis of IFALD that will guide treatment and help in the selection of patients and timing of transplantation.

Chronic biochemical cholestasis in patients receiving home parenteral nutrition: prevalence and predisposing factors

BACKGROUND

Chronic biochemical cholestasis has been shown to be associated with a fivefold increase in histologically advanced liver disease in patients receiving home parenteral nutrition.

AIMS

To investigate prevalence of chronic biochemical cholestasis in home parenteral nutrition patients and examine factors influencing its occurrence.

METHODS

Records of all patients receiving home parenteral nutrition for >6 months treated at a single centre were reviewed and plasma biochemistry recorded. Logistic regression analysis was employed to identify factors associated with prevalence of chronic biochemical cholestasis.

RESULTS

Records of 113 patients were reviewed. The point prevalence of chronic biochemical cholestasis was 24%, increasing to 28% if patients receiving parenteral fluid and electrolytes only were excluded. In multivariate analysis, presence of colon in continuity was associated with a significantly lower prevalence of chronic biochemical cholestasis, while total parenteral calorie intake was associated with a higher prevalence of chronic biochemical cholestasis. No association was seen between small intestinal lengths or between parenteral lipid intake and chronic biochemical cholestasis in multivariate analysis.

CONCLUSIONS

Chronic biochemical cholestasis is common in patients receiving home parenteral nutrition. High parenteral calorie intake and lack of a colon in continuity with small intestine are independently associated with an increased risk of chronic biochemical cholestasis.

Glycemic response and health--a systematic review and meta-analysis: the database, study characteristics, and macronutrient intakes

BACKGROUND

Reduction of dietary glycemic response has been proposed as a means of reducing the risk of diabetes and coronary heart disease. Its role in health maintenance and management, alongside unavailable carbohydrate (eg, fiber), is incompletely understood.

OBJECTIVE

We aimed to assess the evidence relating the glycemic impact of foods to a role in health maintenance and management of disease.

DESIGN

We searched the literature for relevant controlled dietary intervention trials on glycemic index (GI) according to inclusion and exclusion criteria, extracted the data to a database, and synthesized the evidence via meta-analyses and meta-regression models.

RESULTS

Among literature to January 2005, 45 relevant publications were identified involving 972 subjects with good health or metabolic disease. With small reductions in GI (<10 units), increases in available carbohydrate, energy, and protein intakes were found in all studies combined. Falling trends in energy, available carbohydrate, and protein intakes then occurred with progressive reductions in GI. Fat intake was essentially unchanged. Unavailable carbohydrate intake was generally higher for intervention diets but showed no trend with GI (falling or rising). Among studies reporting on GI, variation in glycemic load was approximately equally explained by variation in GI and variation in available carbohydrate intake. An exchange of available and unavailable carbohydrate (approximately 1 g/g) was evident in these studies.

CONCLUSIONS

Among GI studies, observed reductions in glycemic load are most often not solely due to substitution of high for low glycemic carbohydrate foods. Available carbohydrate intake is a confounding factor. The role of unavailable carbohydrate remains to be accounted for.

Metabolic cross talk between the colon and the periphery: implications for insulin sensitivity

Until recently, a glance at a standard undergraduate textbook would have given the impression that the colon was merely a storage organ for faeces and maybe something about the absorption of electrolytes and water. In reality, the colon is a highly-metabolically-active organ, the function of which has implications not only for the remainder of the digestive tract, but also for peripheral organs such as adipose tissue (AT), liver and skeletal muscle. The present review focuses on two distinct but complementary areas: (1) the metabolic adaptation that occurs following surgical removal of colonic tissue; (2) the effect of modulating the colon in situ in terms of postprandial metabolism, insulin sensitivity and disease risk. Work in these two areas points to the colon being important in modulating normal tissue insulin sensitivity. The role of fatty acids is central to the insulin sensitivity hypothesis. AT acts as a daily 'buffer' for fatty acids. However, following colonic resection there is an apparent change in AT function. There is an increase in the AT lipolysis rate, resulting in the release of excess fatty acids into the circulation and consequently the take up of excess fatty acids into skeletal muscle. This resultant increase in either storage of lipid or its oxidation would result in a reduction in insulin sensitivity. The insulin-sensitising effects of high-fibre diets are also related to changes in AT function and fatty acid metabolism, but manipulating colonic tissue in situ allows the mechanisms to be elucidated. This research area is an exciting one, involving the potential role of SCFA (the absorbed by-products of colonic bacterial fermentation) acting directly on peripheral tissues, following the recent identification of G-protein-coupled receptors specific for these ligands.

Quantitative kinetics of glucose appearance and disposal following a13C-labelled starch-rich meal: comparison of male and female subjects

In the UK, starch contributes up to 25 % of energy intake in adults (). The present study investigated the acute response to a starchy meal on whole-body glucose metabolism and assessed insulin sensitivity in men compared with women. Low insulin sensitivity has been postulated to pre-dispose individuals to a cluster of associated abnormalities known to increase the risk of CHD. Metabolic responses to a13C-labelled meal were determined in conjunction with a primed continuous infusion of D-[6,6-2H]glucose in groups of healthy age- and BMI-matched men and women. Peripheral plasma glucose disposal (Gd) was computed using non-steady state kinetics in a single compartment model, simultaneously with determination of whole-body net glucose oxidation by indirect calorimetry. Insulin sensitivity was derived using cumulative Gd as the dependent variable, and time and the integrated insulin concentration as independent variables. The female group had the higher fractional rate of glucose appearance in plasma from starch (P=0·019) immediately after ingestion. Females also had a higher rate of plasma Gd and a significantly higher insulin-dependent Gd (6·8v.5·6 μg glucose/(min.kg) per pmol insulin,P<0·05) compared with the males. A smaller absolute pool of endogenous glucose in females allowed the rate of exogenous13CO2production to be significantly higher in the females (P=0·007) corresponding also to a significantly higher (P<0·05) carbohydrate oxidation rate obtained by indirect calorimetry. The present study suggests that during the ingestion of a starchy meal, females exhibit higher glucose flux and greater whole-body insulin sensitivity than males.

Effects of meal frequency and high-fibre rye-bread diet on glucose and lipid metabolism and ileal excretion of energy and sterols in ileostomy subjects

OBJECTIVE

To investigate the effect of a rye, high-fibre diet (HFD) vs a wheat, low-fibre diet (LFD), meal frequency, nibbling (Nib, seven times a day) or ordinary (Ord, three times a day), and their combined effects on blood glucose, insulin, lipids, urinary C-peptide and ileal excretion of energy, cholesterol and bile acids in humans.

DESIGN

LFD period with Nib or Ord meal frequency followed by an HFD diet with Nib or Ord meal frequency in randomized, crossover design.

SETTING

Outpatients of ileostomy volunteers were called for an investigation in research word.

SUBJECTS

A total of 10 subjects (two female subjects, age 34 and 51 y; eight males, mean age 54.4 y, range 43-65 y) participated in the experiment. All subjects were proctocolectomized for ulcerative colitis (mean 16.0 y, range 8-29 y before the study).

INTERVENTION

In total, 10 ileostomy subjects started with LFD for 2 weeks, the first week on either Nib (five subjects) or Ord (five subjects) and the second week on the other meal frequencies, in a crossover design, followed by a wash-out week, and continued with HFD period for 2 weeks in the same meal frequency manner. All foods consumed in both Nib or Ord regimens were identical and a high-fibre rye bread was used in the HFD period and a low-fibre wheat bread in the LFD period.

MAIN OUTCOME MEASURES

Day-profiles of blood glucose, insulin and lipids, blood lipids before and after dietary intervention, and excretion of steroids in the effluents and C-peptide in the urine.

RESULTS

During the Nib regimen, plasma glucose and insulin peaks were lower at the end of the day with HFD compared with LFD. Urinary C-peptide excretion was significantly higher in the day-time on LFD compared with HFD (LFD-Ord vs HFD-Ord, P < 0.01; LFD-Nib vs HFD-Nib, P < 0.01). Plasma free-cholesterol, total cholesterol, triglycerides and phospholipids were significantly higher (P < 0.05) after LFD than after HFD with the Nib regimen. A higher excretion of energy (P < 0.05) and chenodeoxycholic acid (P < 0.05) were observed with HFD compared with LFD regardless of meal frequency. A higher daily excretion of cholic acid, total bile acids, cholesterol, net cholesterol and net sterols (P < 0.05) was observed on HFD compared with LFD with the Nib regimen.

CONCLUSIONS

An HFD decreased insulin secretion measured as a decreased excretion of C-peptide in urine and as decreased plasma insulin peaks at the end of the day during a Nib regimen. The smoother glycaemic responses at the end of the day during a Nib regimen may be a consequence of a second meal phenomenon, possibly related to the nature of dietary fibre complex.