Carbohydrate-restricted diets and Type 1 diabetes mellitus: research considerations

Chronic exposure to nanocellulose altered depression-related behaviors in mice on a western diet: The role of immune modulation and the gut microbiome

AIMS

To determine if cellulose nanofibrils (CNF) have potential applications as food additives.

MATERIALS AND METHODS

Male C57BL/6 mice on a Western diet were exposed to CNF for one month at a dose of 30 mg/kg by gavage. Male NOD mice, a model for type 1 diabetes (T1D), were used in a six-month study.

KEY FINDINGS

Sequencing analysis of 16S rRNA genes suggested significant changes in gut microbiome of male C57BL/6 mice exposed to CNF. Analysis of functional metagenomics indicated that many of the functional contents that might be altered following CNF ingestion were associated with lipid and carbohydrate processing. Further studies in NOD mice suggested that there were some decreases in the blood glucose levels during the insulin tolerance test and glucose tolerance test following CNF treatment. However, these small decreases were not considered biologically meaningful as there were no significant changes in either the area under the curve or the first-order rate constant for glucose disappearance. Moreover, serum concentrations of cytokines/chemokines including IL-3, IL-12(p70) and the keratinocyte chemoattractant were increased following chronic exposure to CNF. In addition, behavioral studies suggested that the percentage of immobility time during the tail-suspension test was significantly increased following six months of exposure to CNF in NOD mice, signifying an increase in depression-related behavior.

SIGNIFICANCE

Collectively, long-term CNF consumption was associated with changes in the ecology of the gut microbiome, immune homeostasis, and possibly energy metabolism and mental health in male NOD mice on a Western diet.

The effect of the modified fat-protein unit algorithm compared with that of carbohydrate counting on postprandial glucose in adults with type-1 diabetes when consuming meals with differing macronutrient compositions: a randomized crossover trial

BACKGROUND

The optimization of glucose control in type-1 diabetes is challenged by postprandial glycemic variability. This study aimed to compare the postprandial glycemic effects of carbohydrate counting and the modified fat-protein unit (FPU) algorithms following meals with different protein and fat emphases in adults with type-1 diabetes.

METHODS

Thirty adults with type-1 diabetes aged 18 to 45 years participated in a randomized crossover trial. In a random order, participants consumed four test meals with equivalent energy and different macronutrient emphases on four separate mornings. The modified FPU algorithms and carbohydrate counting were used to determine the insulin dose for the test meals. A continuous glucose monitoring system was used to measured postprandial glycemia.

RESULTS

Compared with carbohydrate counting, the modified FPU algorithm significantly decreased the late postprandial mean glucose levels (p = 0.026) in high protein-fat meals. The number of hypoglycemia episodes was similar between insulin dosing algorithms for the high protein-fat meals; hypoglycemic events were considerably higher for the modified FPU in the normal protein-fat meal (p = 0.042).

CONCLUSIONS

The modified FPU algorithm may improve postprandial glycemic control after consuming high protein-fat meals in adults with type-1 diabetes but may result in increased hypoglycemia risk when used with a normal protein-fat meal.

Low-carbohydrate diets in type 1 diabetes: balancing benefits and risks

PURPOSE OF REVIEW

Interest in the use of calorie restriction with low-carbohydrate diets for patients with type 1 diabetes appears to be increasing despite physicians' discomfort about its longer term outcomes. A divergence in opinion regarding the balance of benefits and safety may lead to patient disengagement from conventional medical supervision. This review describes the current evidence regarding the benefits and risks of these diets and suggests a way forward to addressing this potential misalignment between the aims of patients and their physicians.

RECENT FINDINGS

Benefits on glycaemia are observed in many studies, with improved HbA1c, time within target range and reduced glycaemic variability. A characteristic lipid profile with high LDL cholesterol is observed in many patients, but association with future cardiovascular events is undefined. A negative impact on growth has been identified in the paediatric population, and impact on mental health and disordered eating is of theoretical concern, without measurement in clinical studies.

SUMMARY

Patients will continue to trial and, with immediate glycaemic benefits, potentially remain on lower carbohydrate diets irrespective of concern by treating physicians about potential longer term risks. A supportive multidisciplinary approach with greater nutritional supervision and more research is required, to allow these patients to achieve their desired glycaemic outcomes without compromising longer term safety.

Therapeutic effect and rebound evaluation of dapagliflozin on glycated hemoglobin (HbA1c) in type 1 diabetes mellitus patients

Dapagliflozin has been used to treat patients with type 1 diabetes mellitus; however, the actual drug efficacy of dapagliflozin on glycated hemoglobin (HbA1c) and whether there is a rebound from dapagliflozin efficacy on HbA1c remain unknown. The present study aimed to explore the actual therapeutic effect and rebound situation of dapagliflozin on HbA1c in type 1 diabetes mellitus patients. A total of 1,594 type 1 diabetes mellitus patients were enrolled for analysis using a non-linear mixed effect model from randomized controlled trials from published literature works including two 5 mg/day dapagliflozin dosage groups and three 10 mg/day dapagliflozin dosage groups. The change rate of HbA1c from a baseline value was chosen as a dapagliflozin pharmacodynamic evaluation index. After deducting control group effects, the therapeutic effect of 5 and 10 mg/day dapagliflozin on HbA1c in type 1 diabetes mellitus patients had no significant difference. In addition, the actual maximal efficacy (AE_max) of dapagliflozin on HbA1c was -6.24% at week 9. When it reached the AE_max, the dapagliflozin pharmacodynamic rebound on HbA1c occurred, and when the treatment was continued for 0.5 and 1 year, the actual efficacies were -4.70% (75% AE_max) and -3.27% (52% AE_max), respectively. This was the first time to clarify the actual therapeutic effect and rebound situation of dapagliflozin on HbA1c in type 1 diabetes mellitus patients, providing a reference value for clinical practices.