Predictors of gastric myoelectrical activity in type 2 diabetes mellitus

Novel insights into the pathogenic impact of diabetes on the gastrointestinal tract

Type 2 and type 1 diabetes are common endocrine disorders with a progressively increasing incidence worldwide. These chronic, systemic diseases have multiorgan implications, and the whole gastrointestinal (GI) tract represents a frequent target in terms of symptom appearance and interdependent pathophysiological mechanisms. Metabolic alterations linked with diabetic complications, neuropathy and disrupted hormone homeostasis can lead to upper and/or lower GI symptoms in up to 75% of diabetic patients, with multifactorial involvement of the oesophagus, stomach, upper and lower intestine, and of the gallbladder. On the other hand, altered gastrointestinal motility and/or secretions are able to affect glucose and lipid homeostasis in the short and long term. Finally, diabetes has been linked with increased cancer risk at different levels of the GI tract. The presence of GI symptoms and a comprehensive assessment of GI function should be carefully considered in the management of diabetic patients to avoid further complications and to ameliorate the quality of life. Additionally, the presence of gastrointestinal dysfunction should be adequately managed to improve metabolic homeostasis, the efficacy of antidiabetic treatments and secondary prevention strategies.

Disturbed gastric motility in patients with long-standing diabetes mellitus

Purpose: Gastric dysmotility has been reported in patients with long-standing diabetes mellitus (DM). Some patients with DM are diagnosed as diabetes gastroparesis and have several upper gastrointestinal (GI) symptoms such as appetite loss and abdominal pain. This study aimed to identify the relationship between gastric motility and upper GI symptoms in patients with long-standing DM. Method: This study was conducted among 23 patients with DM and 15 healthy controls. All the patients with DM were receiving insulin treatment and had at least one history of incidence of diabetic nephropathy, retinopathy or neuropathy. Gastric motility was evaluated using electrogastrography (EGG) and gastric emptying using the ¹³C-acetic acid breath test. The most severe upper gastrointestinal symptoms were assessed in all patients. Results: Compared to healthy controls, patients with long-standing DM showed a significantly lower percentage of normogastria at the postprandial state with a lower power ratio in EGG. Gastric emptying was significantly delayed in patients with DM in the overall analysis. Sixteen patients with DM (69.6%) demonstrated abnormalities in either gastric myoelectrical activity or gastric emptying. Among patients with abnormal EGG or delayed gastric emptying, 12 had some GI symptoms, compared with 3 patients with normal gastric motility. No significant correlation was observed between the gastric emptying parameters and HbA1c values. Conclusion: Patients with long-standing DM showed gastric dysmotility, including impaired gastric myoelectrical activity and delayed gastric emptying. Gastric dysmotility appears to be closely correlated with upper GI symptoms in patients with long-standing DM.

Adipocytes-released Peptides Involved in the Control of Gastrointestinal Motility

The present review focuses on adipocytes-released peptides known to be involved in the control of gastrointestinal motility, acting both centrally and peripherally. Thus, four peptides have been taken into account: leptin, adiponectin, nesfatin-1, and apelin. The discussion of the related physiological or pathophysiological roles, based on the most recent findings, is intended to underlie the close interactions among adipose tissue, central nervous system, and gastrointestinal tract. The better understanding of this complex network, as gastrointestinal motor responses represent peripheral signals involved in the regulation of food intake through the gut-brain axis, may also furnish a cue for the development of either novel therapeutic approaches in the treatment of obesity and eating disorders or potential diagnostic tools.

High prevalence of esophageal dysmotility in asymptomatic obese patients

BACKGROUND

Obesity is an important health problem affecting >500 million people worldwide. Esophageal dysmotility is a gastrointestinal pathology associated with obesity; however, its prevalence and characteristics remain unclear. Esophageal dysmotilities have a high prevalence among obese patients regardless of gastrointestinal symptoms.

OBJECTIVE

To identify the prevalence of esophageal dysmotility among obese patients. The secondary goals were to characterize these pathologies in obese patients and identify risk factors.

METHOD

A prospective study from January 2009 to March 2010 at the University of Montreal Hospital Centre (Montreal, Quebec) was performed. Every patient scheduled for bariatric surgery underwent preoperatory esophageal manometry and was included in the study. Manometry was performed according to a standardized protocol with the following measures: superior esophageal sphincter - coordination and release during deglutition; esophageal body - presence, propagation, length, amplitude and type of esophageal waves of contraction; lower esophageal sphincter - localization, tone, release, intragastic pressure and intraesophageal pressure. All reference values were those used in the digestive motility laboratory. A gastrointestinal symptoms questionnaire was completed on the day manometry was performed. Chart reviews were performed to identify comorbidities and treatments that could influence the results.

RESULTS

A total of 53 patients were included (mean [± SD] age 43 ± 10 years; mean body mass index 46 ± 7 kg/m; 70% female). Esophageal manometry revealed dysmotility in 51% (n=27) of the patients. This dysmotility involved the esophageal body in 74% (n=20) of the patients and the inferior sphincter in 11% (n=3). Mixed dysmotility (body and inferior sphincter) was found in 15% (n=4) of cases. The esophageal body dysmotilities were hypomotility in 85% (n=23) of the patients, either from insignificant waves (74% [n=20]), nonpropagated waves (11% [n=3]) or low-amplitude waves (33% [n=9]). Gastroesophageal symptoms were found in 66% (n=35) of obese patients, including heartburn (66% [n=23]), regurgitation (26% [n=9]), dysphagia (43% [n=15]), chest pain (6% [n=2]) and dyspepsia (26% [n=9]). Among symptomatic patients, 51% (n=18) had normal manometry and 49% (n=17) had abnormal manometry (statistically nonsignificant). Among asymptomatic patients (n=18), 44% (n=8) had normal manometry and 56% (n=10) had abnormal manometry (statistically nonsignificant). Furthermore, no statistical differences were found between the normal manometry group and the abnormal manometry group with regard to medication intake or comorbidities.

CONCLUSION

Esophageal dysmotilities had a high prevalence in obese patients. Gastrointestinal symptoms cannot predict the presence of esophageal dysmotility. Hypomotility of the esophageal body is the most common dysmotility, especially from the absence of significant waves.

Digestive function of the stomach

The core function of the human stomach is as an aid to digestion. The four key components of gastric digestive function are its function as a reservoir, acid secretion, enzyme secretion and its role in gastrointestinal motility. The reservoir capacity of the stomach allows it to increase its volume significantly while internal pressure increases only slightly. Acid secretion is a very important non-immunological defence against invading pathogens as well as being an important mechanism for vertebrates to have more complex diets. Stimulation of acid secretion involves the translocation of H+/K+-ATPases to the apical membrane of the parietal cell. The stomach is also an important endocrine organ producing an array of peptide hormones important for both enteric and non-enteric physiology including ghrelin and leptin. In addition to the reservoir function, the stomach also plays an important motility role as a pump, which anatomically is provided by the distal two thirds of the corpus, the antrum and the pylorus. This article examines those four functions and the role that they play in normal physiologic function and examines how they may play a role in pathologic states.

Prediction of octreotide efficacy by electrogastrography in the treatment of patients with esophageal variceal hemorrhage

Our aim is to investigate the significance of electrogastrography in the treatment of esophageal variceal hemorrhage with octreotide. Electrogastrography was performed in patients with esophageal variceal hemorrhage before and during the treatment consisting of various doses of octreotide (25 ug h(-1) group and 50 ug h(-1) group). The dominant power of electrogastrography and its relationship with the hemostatic efficacy of octreotide treatment were evaluated. Dominant power of electrogastrography decreased significantly during treatment with octreotide (P < 0.05). The reduction in the amplitude of dominant power in the 50 ug h(-1) group was significantly larger than in the 25 ug h(-1) group (P < 0.05), and it was correlated with hemostatic efficacy of octreotide treatment. We conclude that octreotide treatment in patients with esophageal variceal hemorrhage can result in a significant decrease of dominant power, which correlates with the hemostatic efficacy of octreotide, so the change of dominant power could be used as a predictor of evaluating the treatment efficacy of octreotide in esophageal variceal hemorrhage patients.

Prevalence of abnormal gastric emptying in asymptomatic women with newly detected diabetes and its reversibility after glycemic control-a prospective case control study

OBJECTIVE

Effects of systemic hyperglycemia and normoglycemia on gastric emptying in people with type 2 diabetes are not clear. The aim of the study was to investigate the gastric emptying time in people with newly detected diabetes before and after control of diabetes compared with healthy controls.

METHODS

Gastric emptying to solid meal was studied in 30 asymptomatic women with newly detected diabetes before and after achieving euglycemia and compared with 20 healthy age, sex and weight matched controls using egg white labelled with Technetium 99m Sulfur Colloid.

RESULTS

Delayed gastric emptying was seen in 90% of women with diabetes and none in healthy controls. Lag phase was 83.1±11.8 min in cases compared to 37.2±4.0 in controls (p=0.05). Gastric emptying at 4h was 46.73%±4.84% in cases and 97.65%±0.59% in controls (p=0.05).T50 was 250±8.8 min in cases against 94.70±5.10 min in controls (p<0.05). After control of diabetes, lag phase normalized to 37.2±4.0 min against 35.2±4.6 min in controls. Similarly all other parameters also normalized after control of diabetes.

CONCLUSIONS

Delayed gastric emptying to solids was seen in 90% of women with type 2 diabetes at the time of hyperglycemia and normalized after control of diabetes.

The CLOCK 3111T/C SNP is associated with morning gastric motility in healthy young women

Circadian locomotor output cycles kaput (CLOCK) molecule plays major roles in circadian rhythmicity and regulates daily physiological processes including digestive activity. Therefore, we hypothesized that the CLOCK 3111T/C single nucleotide polymorphism (SNP) might have adverse effects on the regulation of gastric motility. Based on the hypothesis, we investigated whether this SNP was associated with morning gastric motility. Ninety-five female university students (19.6±0.2 years) completed life-style questionnaires. Gastric motility, evaluated by electrogastrography (EGG), blood pressure (BP), and heart rate variability (HRV) were measured at 8:30 a.m. after an overnight fast. To determine the gastric motility, the spectral powers and dominant frequency (DF, a peak of the spectrum) of the EGG were calculated. No significant differences were found in breakfast frequency, energy intake, or HRV between CLOCK 3111T/C minor C allele (T/C or C/C) and T/T subjects. However, C allele carriers showed significantly lower DF than T/T subjects, suggesting slower gastric motility. Moreover, C allele carriers had a lower heart rate (HR) and tended to have lower diastolic BP compared with T/T subjects. These results support our hypothesis that this SNP is likely correlated with morning gastric motility. Such attenuated gastric and cardiovascular function that characterized CLOCK 3111C allele carriers could be affecting biological behavior in the morning.

Obesity and symptoms suggestive of gastroparesis in patients with type 2 diabetes and neuropathy

BACKGROUND

Associated with neuropathy, symptoms suggestive of gastroparesis are common in patients with type 2 diabetes mellitus (T2DM) and include nausea, vomiting, bloating and early satiety. Gastric motor abnormalities have been reported in obese patients, and obesity is associated with T2DM. An association between obesity and gastroparesis symptoms in diabetic patients with neuropathy has not been investigated.

METHODS

In this nested case-control study, 161 patients with neuropathy were identified from within a cross-sectional survey of 380 T2DM patients. Of these, 134 (83.2%, "cases") had at least one cardinal symptom suggestive of gastroparesis. The remaining symptom-free subjects served as controls. Logistic and general linear modeling was used to assess associations between obesity and the presence and number of symptoms.

RESULTS

Subjects were 66.6±10 years of age. Cases were significantly more likely than controls to be obese (89% vs. 77%, P=.04), female (55.6% vs. 33.3%) and hypertensive (90.2% vs. 63%, P=.001) and to report adherence to diet (87.4% vs. 66.7%, P=.007). In a logistic regression model including sex, hypertension, antiaggregant therapy, adherence to diet therapy and an obesity-by-sex interaction term, obesity emerged as a significant independent predictor of any cardinal symptom suggestive of gastroparesis (odds ratio 9.86, 95% confidence interval 1.4-69.2, P=.02). Obesity was also identified as a significant independent predictor of number of cardinal symptoms suggestive of gastroparesis in the general linear model. Obese subjects reported significantly more early satiety (61.5% vs. 35.2%, P=.001), fullness (63.7% vs. 40.8%, P=.004), bloating (70.3% vs. 49.3%, P=.006) and abdominal distention (71.4 vs. 50.7%, P=.007) than nonobese subjects. Further, obese subjects reported more cardinal symptoms suggestive of gastroparesis symptoms (4.2±2.4 vs. 3.1±2.5, P=.01).

CONCLUSIONS

Obesity emerged as a significant independent predictor of cardinal symptoms suggestive of gastroparesis in patients with T2DM and neuropathy. This finding suggests that mechanisms in addition to neuropathy play a role in the generation of symptoms suggestive of gastroparesis in this patient population.

Gastric dysmotility after liquid bolus ingestion in systemic sclerosis: an ultrasonographic study

Gastric involvement appears quite commonly in systemic sclerosis (SSc). The aim of this study was to evaluate gastric wall motility using ultrasonography, a noninvasive method able to track both filling and emptying of fundus and antrum. The study was performed in 20 SSc patients and 20 healthy control subjects. Gastric filling and emptying were evaluated by transabdominal ultrasonography, measuring changes in fundus and antral areas over a 1-h period after ingestion of a liquid bolus (500 ml of mineral water). Areas of both gastric fundus and antrum at basal evaluation were found to be smaller in SSc patients than in healthy controls. Gastric filling was significantly reduced after ingestion of liquid bolus. Gastric emptying was delayed both in fundus and antrum. No significant differences of gastric wall motility have been observed in different subsets of SSc patients. Our findings show that gastric dysmotility is frequent and severe in SSc patients, contributing to the gastrointestinal disturbances which are very common in this disease.

Diverse roles of leptin in the gastrointestinal tract: modulation of motility, absorption, growth, and inflammation

OBJECTIVE

Leptin was discovered in 1994 as a hormone produced by adipose tissue with a modulatory effect on feeding behavior and weight control. Recently, the stomach has been identified as an important source of leptin and growing evidence has shown diverse functions for leptin in the gastrointestinal tract.

METHODS

Using leptin as a keyword in PubMed, more than 17 000 articles were identified, of which more than 500 articles were related to the role of leptin in the gastrointestinal tract. Available abstracts were reviewed and more than 200 original articles were reviewed in detail.

RESULTS

The available literature demonstrated that leptin can modulate several important functions of the gastrointestinal tract. Leptin interacts with the vagus nerve and cholecystokinin to delay gastric emptying and has a complex effect on motility of the small bowel. Leptin modulates absorption of macronutrients in the gastrointestinal tract differentially in physiologic and pathologic states. In physiologic states, exogenous leptin has been shown to decrease carbohydrate absorption and to increase the absorption of small peptides by the PepT1 di-/tripeptide transporter. In certain pathologic states, leptin has been shown to increase absorption of carbohydrates, proteins, and fat. Leptin has been shown to be upregulated in the colonic mucosa in patients with inflammatory bowel disease. Leptin stimulates gut mucosal cell proliferation and inhibits apoptosis. These functions have led to speculation about the role of leptin in tumorigenesis in the gastrointestinal tract, which is complicated by the multiple immunoregulatory effects of leptin.

CONCLUSION

Leptin is an important modulator of major aspects of gastrointestinal tract functions, independent of its more well-described roles in appetite regulation and obesity.