A joint research group at Wakayama Medical University and Hokkaido University has revealed the possibility that ingesting linoleic acid before a meal can improve a sudden rise in blood sugar after a meal.
Previous studies have shown that GPR40 and GPR120 receptors in the small intestine secrete hormones such as GLP-1 when they sense fatty acids. Since GLP-1 increases the amount of insulin released from the pancreas when blood glucose levels rise, administration of a drug that responds to GPR40 one hour before a meal improved postprandial blood glucose elevation in rats and increased response to GPR1. It has been reported that administering the drug for more than one month can improve the symptoms of type 120 diabetic mice, which are resistant to insulin.
In this study, we focused on linoleic acid contained in vegetable oil, which is a fatty acid that reacts with both GPR40 and GPR120. investigated.
As a result, in the linoleic acid administration group, compared with the group in which olive oil was administered instead of linoleic acid, the peak of the blood glucose increase was delayed by 30 minutes, confirming the effect of slowing the blood glucose increase.Since this effect was also confirmed in type 1 diabetic rats that cannot secrete insulin, it was presumed that it was not due to the action of insulin.
Therefore, when the movement of the stomach was examined, it was confirmed that glucose was retained in the stomach longer than usual in the linoleic acid administration group. In addition to stimulating insulin secretion, GLP-1 also has the effect of suppressing gastric motility.GLP-1 blood levels increased in the linoleic acid-administered group, suggesting the possibility that administration of linoleic acid releases GLP-1 into the blood, slowing the movement of the stomach.Furthermore, we found that this effect was due to GPR40 rather than GPR120.
The effect of suppressing postprandial blood glucose elevation by linoleic acid intake clarified in this study was also confirmed by the intake of α-linolenic acid, one of the fatty acids contained in linseed oil and perilla oil.The results of this research are expected to be applied to patients with diabetes, including type 1 diabetes, who are prone to postprandial hyperglycemia.
Paper information:[Frontiers in Pharmacology] Oral administration of linoleic acid immediately before glucose load ameliorates postprandial hyperglycemia
