Bariatric Surgery in Obese Patients with Type 1 Diabetes: Effects on Weight Loss and Metabolic Control

Background

Type 1 diabetes patients, although typically lean, experience an increased prevalence of obesity, and bariatric surgery is considered in severe cases. Bariatric surgery in such patients leads to significant weight loss and decreased insulin requirements; however, effects on glycemic control remain discussed. We assessed, in obese patients with type 1 diabetes, the effects of bariatric surgery upon body weight, body composition, and glycemic control, including the occurrence of hypoglycemic events.

Methods

Thirteen obese patients with type 1 diabetes who underwent bariatric surgery (Roux-en-Y gastric bypass n?=?6, sleeve gastrectomy n?=?7) were matched with obese patients without diabetes and with type 2 diabetes patients during 12 months of follow-up. Outcomes included body weight, DXA-assessed body composition, HbA1c, and incidence of hypoglycemia.

Results

At 12 months, median surgery-induced weight loss was 27.9 % (21.1–33.3), 26.1 % (24.8–29.7), and 27.5 % (21.8–32.1) in patients with type 1 diabetes, type 2 diabetes, and without diabetes, respectively, with no significant differences across the groups. Similar findings were observed for body fat changes. At 12 months, median HbA1c decreased from 8.3 to 7.6 % in type 1 diabetes patients versus 8.0 to 5.9 % in type 2 diabetes patients (P?=?0.04 between the groups). In type 1 diabetes patients, the number of reported minor hypoglycemia increased transiently only at 6 months. Two patients reported severe hypoglycemia (one episode each).

Conclusions

Type 1 diabetes patients benefit from bariatric surgery in terms of weight loss and glycemic control. Close monitoring of insulin therapy appears warranted to prevent minor hypoglycemia in the first months post-surgery.

     

Acute systemic inflammation induces central mitochondrial damage and mnesic deficit in adult Swiss mice

The aim of this study was to investigate how the brain is affected during systemic inflammation. For this purpose, Swiss mice were challenged with a single intraperitoneal dose of lipopolysaccharide (LPS; 250microg/mouse) to mimic aspects of systemic infection. Spatial learning in Y-maze test demonstrated a differential learning profile during the training test between control and LPS-treated mice, with an alteration in the latter group. We show that systemic LPS-induced inflammation and oxidative injury as assessed by reactive oxygen species (ROS) and nitrites/nitrates (NOx) production associated with reduced glutathione (GSH) depletion, cyclooxygenase-2 (COX-2) expression, and lipid peroxidation. LPS also induced a loss in mitochondrial integrity as shown by a significant decrease in membrane potential and impairment in mitochondrial redox activity. Thus, peripheral inflammation by producing brain inflammation and oxidative injury causes mnesic deficits. It remains to determine whether such events can induce neuronal dysfunction/degeneration and, with time, lead to cholinergic deficiency, amyloid deposits and cognitive impairments as they occur in Alzheimer's disease.     

Induction of protective immunity by synthetic Vibrio cholerae hexasaccharide derived from V. cholerae O1 Ogawa lipopolysaccharide bound to a protein carrier

Synthetic antigens that mimic the terminal hexasaccharide epitope of the O-specific polysaccharide of Vibrio cholerae O1, serotype Ogawa, were conjugated to bovine serum albumin (BSA). Conjugates with carbohydrate-to-carrier molar ratios of 15.5:1, 9.2:1, and 4.6:1 were tested for immunogenicity and efficacy in mice. The role of preimmunity to BSA and the use of adjuvant in the generation of the serologic response to the O-specific polysaccharide and protection against virulent V. cholerae was examined. Preimmunity to BSA did not affect the anti-Ogawa titers but seemed to enhance the protective capacity of antiserum. All 3 conjugates were immunogenic, but adjuvant was effective at inducing higher and earlier antibody responses. In tertiary serum samples, a correlation was found between vibriocidal activity and protection. The protective capacity of antiserum was evident in serum from mice immunized with all conjugates, but it was highest in the groups that received the conjugate with the lowest level of substitution. Further studies are required to increase understanding of the reason for differential protection.     

Sleep apnea syndrome: improved detection of respiratory events and cortical arousals using oxymetry pulse wave amplitude during polysomnography

Respiratory events (RE) during sleep induce cortical arousals (A) and marked changes in autonomic markers in sleep apnea syndrome (SAS). The aims of the study were double. First, we assessed whether pulse wave amplitude (PWA) added to polysomnography (PSG) could improve RE and A detection; second, we wanted to know whether the quality of detection of these two parameters could be improved using PWA. Respiratory disturbance index (RDI) and A were randomly scored twice by the same observer in 12 male patients with SAS. The first scoring was done using conventional PSG signals, the second scoring adding PWA to PSG. We also measured interobserver agreement by randomly selecting and reading 100 PSG sequences of 5 min with and without PWA by two observers. Adding PWA to PSG parameters allowed to detect significantly more RDI (53.9 ± 21.6 h⁻¹ versus 48.3 ± 22.3 h⁻¹, p < 0.001) and more A (68.0 ± 14.4 versus 59.4 ± 16.5, p < 0.001). Moreover, after using PWA, there was no significant disagreement between two observers for detecting RE, showing better quality of RE detection. PWA is a simple and cheap parameter that improves the diagnostic value of conventional PSG in sleep apnea syndrome by better detecting respiratory events and A.