Xylitol

Xylitol and obesity

• Causes a small blood glucose rise
• GI 7 [2]
• no reactive hypoglycemia observed in study on helathy men after 3h [2]
• Commonly used as an alternative to high-energy supplements in diabetics
• Five-carbon sugar alcohol
• Energy value of 3 kcal/g
• Wide variety of plants, fruits and vegetables
• Plums
• Strawberries
• Raspberries
• Cauliflower [1]
• Absorbed from the small intestine
• Passive diffusion
• Mostly metabolized in the liver [1]

Jaterní metabolismus xylitolu

• Phosphorylated
• Xylulose 5-phosphate (Xu5P)
• Intermediate of the nonoxidative branch of the pentose phosphate pathway
• Activation of protein phosphatase 2A (PP2A) in vitro
• Specifically activates carbohydrate response element binding protein (ChREBP)
• Nuclear transport
• DNA-binding activities [1]

ChREBP

• Transcription factor
• Activates lipogenic enzyme genes
• Acetyl coenzyme A carboxylase (ACC)
• Fatty acid synthase (FAS)
• Stimulates lipogenesis in the liver
• Result in steatosis and obesity [1]

xylulose-5-phosphate

• xylitol metabolite
• Activate carbohydrate response element binding protein
• Promote lipogenic enzyme gene transcription in vitro [1]

Pokusy s xylitolem

• In rats fed a high-fat diet
• 0 g (control)
• 1.0 g/100 kcal (X1)
• 2.0 g/100 kcal (X2) of xylitol
• After the 8-week
• Plasma insulin and lipid concentrations
• Significantly lower in xylitol-fed rats than those in high-fat diet rats
• Gene expression levels of ChREBP and lipogenic enzymes were higher
• Expression of sterol regulatory-element binding protein 1c was lower
• Fatty acid oxidation-related genes were significantly higher in the liver of xylitol-fed rats
• May be beneficial in preventing the development of obesity [1]

Literatura: