Editorial - (2021) Volume 5, Issue 6

Study of the Effects of Glucose Dosage in Parenteral Nutrition on Rat Thiamine Levels
Daisuke Harada*
 
Laboratory of Clinical Nutrition, Naruto Research Institute, Otsuka Pharmaceutical, Kuguhara, Tateiw, Japan
 
*Correspondence: Daisuke Harada, Laboratory of Clinical Nutrition, Naruto Research Institute, Otsuka Pharmaceutical, Kuguhara, Tateiw, Japan, Email:

Published: 23-Nov-2021

Abstract

The objective of this study was to determine the relationship between glucose dosage in parenteral nutrition and reductions in levels of body thiamine in rats. Vitamin-free infusions with differing amounts of glucose were administered to normal or thiamine-deficient rats for 5 days, after which urinary thiamine excretion and the amounts of thiamine in the blood, liver, brain, and skeletal muscles were measured. The total energy dosage was set at three levels (98, 140, and 196 kcal/kg), and the dose of amino acids was constant among all groups. Urinary thiamine excretions on Day 5 decreased with increasing glucose dosage in the infusions. In normal rats, the amount of thiamine in the blood and all organs decreased compared with the diet group; however, no significant differences were found among the infusion groups. In thiamine-deficient rats, on the other hand, the amount of thiamine in the liver and skeletal muscles did not differ significantly among infusion groups; however, the amount of thiamine in the brain and blood decreased with increasing glucose dosage. An organ-specific correlation was found between glucose dosage in infusions and reductions in levels of thiamine. To prevent thiamine deficiencies from affecting the central nervous system, greater caution must be exercised during highcaloric parenteral nutrition. However, a constant supply of thiamine seemed to be essential, irrespective of the amount of energy supplied via parenteral nutrition, to maintain a sufficient level of thiamine in the body.

Introduction

The objective of this study was to determine the relationship between glucose dosage in parenteral nutrition and reductions in levels of body thiamine in rats. Vitamin-free infusions with differing amounts of glucose were administered to normal or thiamine-deficient rats for 5 days, after which urinary thiamine excretion and the amounts of thiamine in the blood, liver, brain, and skeletal muscles were measured. The total energy dosage was set at three levels (98, 140, and 196 kcal/kg), and the dose of amino acids was constant among all groups. Urinary thiamine excretions on Day 5 decreased with increasing glucose dosage in the infusions. In normal rats, the amount of thiamine in the blood and all organs decreased compared with the diet group; however, no significant differences were found among the infusion groups. In thiamine-deficient rats, on the other hand, the amount of thiamine in the liver and skeletal muscles did not differ significantly among infusion groups; however, the amount of thiamine in the brain and blood decreased with increasing glucose dosage. An organ-specific correlation was found between glucose dosage in infusions and reductions in levels of thiamine. To prevent thiamine deficiencies from affecting the central nervous system, greater caution must be exercised during high-caloric parenteral nutrition. However, a constant supply of thiamine seemed to be essential, irrespective of the amount of energy supplied via parenteral nutrition, to maintain a sufficient level of thiamine in the body.

Parenteral Nutrition

Thiamine (vitamin B1) is a vitamin that is essential in energy-producing metabolic pathways, such as the glycolysis-tricarboxylic acid cycle, and represents the most important among various vitamins used in parenteral nutrition (PN) that contains glucose as the major source of energy. Thiamine deficiencies can lead to serious outcomes, including Wernickeâ??s encephalopathy and beriberi with lactic acidosis. Therefore, administration of a sufficient amount of thiamine is necessary during PN.

In PN, the amounts of glucose, amino acids, and fats administered are determined according to the patientâ??s nutritional state, disease, and duration of treatment. Used in patients who have lost intestinal function and other patients, Total Parenteral Nutrition (TPN) includes large amounts of glucose as a source of energy, whereas Peripheral Parenteral Nutrition (PPN), which is used in nutrition management for a short period of time, has relatively low glucose dosage because of the limitations on the osmotic pressure of the dosing liquid. Since the publication of the WHO Report in 1965, the practice has been to express thiamine requirements as amounts per human energy intake. Based on this concept, the requirement for thiamine in PN is interpreted as being higher with TPN, which involves greater amounts of glucose administered. In fact, in Japan, the attending physician is obliged to administer thiamine with TPN as mentioned in a Dear Doctor Letter from the Ministry of Health and Welfare (currently the Ministry of Health, Labour and Welfare).

However, with regard to PPN, no notifications like those for TPN have been issued by the administrative authorities, although the guideline from the Japanese Society for Parenteral and Enteral Nutrition emphasizes the necessity of administration of thiamine. The aforementioned thiamine deficiencies during PN have been reported not only with TPN, but also with PPN. The onset of thiamine deficiencies during PN is considered to depend largely on the presence of underlying nutrition disorders in post-gastrectomy patients, in patients following obesity surgery, in patients with eating disorders, and other patients, rather than on the amount of energy supplied in the infusion and the length of the treatment period.