عنوان

A dietary interventional study moderating fat intake in Saudi subjects with metabolic disease

Number

TLets640939

Title Proper

A dietary interventional study moderating fat intake in Saudi subjects with metabolic disease

General Material Designation

[Thesis]

First Statement of Responsibility

Aldesi, Darh Assad D.

Name of Publisher, Distributor, etc.

University of Warwick

Date of Publication, Distribution, etc.

2014

Dissertation or thesis details and type of degree

Thesis (Ph.D.)

Text preceding or following the note

2014

Text of Note

The gut-derived bacteria, endotoxin (lipopolysaccharide), have been observed to be raised in patients with type 2 diabetes mellitus (T2DM) and cardiovascular diseases (CVD) which appears to represent a source of diet induced inflammation exacerbating metabolic disease. To further the current studies on endotoxin induced inflammation investigations examined a cohort of adult Saudi Arabian women with obesity/weight gain and or T2DM to ascertain (1) the impact of a post-prandial high SFA rich meal on systemic inflammation; (2) the direct effect of a 3 month diet intervention on cardiometabolic health (3) and assess how subtle changes in dietary interventions can impact on metabolic risk in different patient groups and what dietary components appear important. A total of 92 Saudi adult women with varying metabolic states [18 nondiabetic (ND) control subjects (Age 24.4±7.9 years; BMI 22.2±2.2 Kg/m2), 24 overweight-plus obese (overweight+) subjects (Age 32.0±7.8 years; BMI 28.5±1.5 Kg/m2) and 50 T2DM patients (Age 41.5±6.2 years; BMI 35.2±7.7 Kg/m2)] were recruited for this 3-month intervention study. Anthropometric data and fasting blood samples were taken at pre- and 3 months post-intervention with glucose, insulin, HOMA-IR, lipid profile and endotoxin measured. To establish whether a high-fat meal alters circulating endotoxin in different metabolic disease states, all subjects were given a high fat standardized meal (75g fat, 5g carbohydrate, 6g protein) after an overnight fast of 12-14 h. Blood samples were drawn via cannula at baseline (0 hour) and post-prandially (1, 2, 3, and 4 hours). For the dietary intervention, participants were prescribed a 500Kcal deficit energy diet less than their daily recommended dietary allowances. Targeted macronutrient composition was 20%-30% fat, <10% of saturated fatty acids, 50%-60% carbohydrates, 15%-20% protein and at least 15g of fibre per 1000 kcal. At baseline and with the exception of HDL-cholesterol, all anthropometric, glycemic parameters, lipid profile and endotoxin were significantly higher in the T2DM group. For the high fat challenge, the most notable changes were the postprandial increases in the triglycerides, insulin, HOMA-IR and endotoxin levels, and subsequent significant decrease in HDL-cholesterol in all groups (p<0.05). These same patterns of changes were observed after 3 months in the overweight+ and T2DM group. Endotoxin was found to be significantly and positively associated with total and LDL-cholesterol (p<0.05), modestly with triglycerides and inversely with HDL-cholesterol (p=NS). For the dietary intervention, significant improvements were noted in all anthropometric measures in the T2DM group and BMI in the overweight+ group (p<0.01). The noted weight loss was secondary to the significant decrease in carbohydrates, fats and total caloric intakes (p<0.05) which translated to a better cardiometabolic health in both groups noted clearly through lipid profile changes. Endotoxin was found to be inversely associated with fiber intake (p<0.05). Fiber intake was found to be positively associated with HDL-cholesterol (p<0.05), which appeared to be an important dietary component to be associated with health improvements. This current thesis expanded our knowledge and understanding on how a high fat oral challenge exacerbates cardiometabolic and inflammatory conditions (including endotoxemia) in Saudi Arabian women with different metabolic states, and how a 3-month caloric restriction may induce weight loss that leads to improved cardiometabolic health. Observations from the present thesis highlight strategies that may potentially be of clinical use in future dietary intervention studies in patients with T2DM and obesity in the Middle Eastern region.

QP Physiology

Aldesi, Darh Assad D.

University of Warwick

Electronic name

p

[Thesis]

276903

a

Y