Effect of Protein Hydrolysates on HbA1c Levels in Pre-diabetics

Diabetes has been recognised as an epidemic globally and within the EU. Environmental and behavioural changes over the last century, such as a sedentary lifestyle, intake of calorie dense/sugary foods and obesity are all significant contributors in creating a dramatic increase in the incidence of diabetes globally. There are about 60 million people, 11% of the total population, with diabetes in the European Region. This number will swell to 15% of the EU population by 2030. Europe spent €89 billion on directly treating and managing diabetes and its related complications in 2011. This cost however is severely understated as the true cost of diabetes also includes indirect costs, such as productivity losses due to lost working time through absenteeism, sickness, early retirement and premature death. The WHO projects that diabetes will be the 7th leading cause of death in 2030 and it is already the fourth in most developed countries in the world.

Additionally, individuals with diabetes are twice as likely to be admitted to hospital. According to the International Diabetes Federation (IDF), diabetes is the number one cause for admission to dialysis and to kidney transplant programmes and is the leading cause of working age blindness. It also accounts for a risk of lower limb amputation of 10 to 12%. Therefore, it is clear that diabetes has a huge and growing impact on individual sufferers as well as placing a huge strain on the health system and the exchequers that have to fund them.

90% of diabetes patients globally have type 2 diabetes and when we refer to diabetes in the document going forward it is type 2 to which we refer. This chronic disease state occurs when the body does not use insulin properly causing glucose levels in the blood to rise higher than normal. This abnormal state over time leads to serious damage to the heart, blood vessels, eyes, kidneys, and nerves. Prediabetic individuals are defined as having blood sugar levels higher than normal but not yet high enough to be classified as Diabetes, and prediabetes is thought of as a clear, early warning sign for diabetes.

Without intervention, prediabetes is likely to become type 2 diabetes in 10 years or less. The increasing number of new cases of prediabetes presents a global concern as it carries large-scale implications towards the future burden on healthcare. Between 2003 and 2011, the prevalence of prediabetes in England alone more than tripled, with 35.3% of the adult population, or 1 in every 3 people, having prediabetes. The International Journal of health science succinctly states a well-accepted fact: "intervention prior to the onset of type 2 diabetes may be the only way of preventing the complications of diabetes". In addition, diabetes once it occurs is irreversible, thus prevention holds a last beacon for epidemic control in the future.

Whilst significant lifestyle changes can be impactful, sustained compliance is very limited and therefore results are poor. As a result, the European Commission has highlighted functional foods as valuable solutions for treatment and prevention of diabetes. A functional food, "beneficially affects one or more target functions in the body beyond adequate nutritional effects in a way that is relevant to either an improved state of health and well-being and/or reduction of risk of disease.

Peptides derived from a range of food materials have been shown to prevent disease i.e. inflammatory disorders [1] osteoporosis [2] high blood pressure [3] or promote health i.e. immunomodulatory [4], antimicrobial [5], anti-oxidative [6], antithrombotic [7], hypo-cholesterolemic [8] activities.

Peptides are protein molecules smaller than 10 kDa that may exist naturally or be derived from full length proteins. Bioactive peptides are defined as specific protein fragments that have positive effects on body functions or conditions and may influence human health [9]. Peptides are produced by hydrolysis of food materials by digestive, microbial, and plant proteolytic enzymes, their levels generally increase during food fermentation [10]. Bioactive peptides with particular amino-acid sequences, which are inactive in the intact protein molecule become bioactive after their release from the intact molecule through the action of digestive enzymes in the body or through the action of proteolytic enzymes in food processing.

Plant hydrolysates have been shown to display a stimulatory effect on the insulin responsive glucose transport protein, GLUT4, which facilitates glucose transport into skeletal muscle. Skeletal muscle is the predominant site of glucose disposal (80%) under insulin-stimulated or post-prandial conditions and so it is hypothesized that one or both of the Nuritas pea and rice protein hydrolysates could help reduce HbA1c levels in those with elevated HbA1c levels (prediabetes).

The main aims are to evaluate the effectiveness of three different daily doses of plant-based hydrolysates versus placebo, when consumed over a 12-week period, at reducing and maintaining glycated haemoglobin (HbA1c) levels in a pre-diabetic population (otherwise healthy subjects with impaired glucose metabolism), as well as post-prandial glucose/insulin levels (oral glucose tolerance test), fructosamine levels, fasting plasma glucose levels, vital signs, physical examinations, weight, blood pressure.