Association between the transcriptional levels of Htr-1a and tryptophan hydroxylase-1 in the hippocampus and the antifatigue effects of leucine on rats with postoperative fatigue.

Tiantian Wu,Jiang Zhu,Zhen Yu,Jing Chen

doi:10.3892/etm.2014.1973

Abstract

Leucine (Leu), a branched-chain amino acid (BCAA), is widely used in clinical practice following severe burns, gastrointestinal surgery, trauma and sepsis. In the present study, the antifatigue effects of BCAAs on a postoperative fatigue (POF) rat model, induced by 70% intestinal resection, were investigated. Leu (16.5 g/l) was administered intraperitoneally at a dose of 18 ml/kg/day. The fatigue level and antifatigue effects of Leu were evaluated by open-field testing on day 1, 3, 5 and 7 after surgery. In addition, mRNA specimens were extracted and measured using a quantitative polymerase chain reaction method. The open-field test results indicated that Leu exhibited a significant antifatigue effect. The total distance travelled and the number of times the rats passed from the outermost grids of an open-top case were greatly improved in the Leu treatment group when compared with the POF model group. With the exception of the normal group, the mRNA expression levels of Htr-1a exhibited a similar trend in all other groups, reaching a climax on day 3 and 5, while being restored to a normal level on day 7. With regard to the Leu intervention group, the mRNA expression level of Htr-1a decreased significantly on day 3 and 5 following surgery. The mRNA expression levels of tryptophan hydroxylase-1 were unchanged in this short time period; however, the levels were increased gradually in the Leu treatment group. Therefore, Leu exhibited an apparent antifatigue effect on various 5-hydroxytryptamine-associated genes.

Highlights

Recovery in the postoperative period is receiving increasing attention
The behavior of the rats in the model group (MG) was apathetic compared with the rats in the Normal group (NG), showing decreased activity, hair loss and poor hygiene due to the lack of cleaning themselves
The injection of Leu improved the behavior of the rats in the Leu‐treated POF model group (LG) when compared with the MG rats

Summary

Introduction

Recovery in the postoperative period is receiving increasing attention. The concept of postoperative fatigue (POF) was first proposed by Professor Christensen [1], and is a common complication following surgery, after enteral surgery. Depression, concentration difficulties, lethargy and weakness may be present for one to three months, even following uncomplicated abdominal surgery [2]. POF increases treatment costs after surgery and burdens patients and their families. Etiological studies of POF have proposed that the condition is an endocrine‐metabolic response to surgical and anesthetic stress. The behavioural and subjective changes during the postoperative convalescence are assumed to be the the physiological and metabolic consequences of surgery [3]; developing a systemic therapy to abate POF and shorten the recovery period is desirable in surgery

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Methods

Results