Glutamine supplementation could help restore post-surgery muscle atrophy – Taiwan study

Glutamine is the most abundant non-essential amino acid in the human body, which gets depleted under conditions such as severe illness or major surgery.

As glutamine is involved in diverse biological processes, including muscle protein synthesis and immunomodulation, its insufficiency can cause significant dysfunction of the gut barrier and wound healing.

Sarcopenia, characterised by degenerative skeletal muscle loss, is increasingly linked to poor surgical outcomes. However, research on the impact of glutamine supplementation on sarcopenia have been inconclusive.

To evaluate whether the intake of glutamine supplements could improve sarcopenia in people with gastric adenocarcinoma (GA) undergoing gastrectomy, a study was conducted by researchers from Taiwan between January 2016 and June 2019.

Of the 516 people analysed, 19.4% received perioperative glutamine supplementation (PGS), which comprised parenteral administration for five days and oral supplementation (Sympt-X) thrice daily for 28 days.

The psoas major muscle area (PMMA) is located at the lower back region of the spine. In this study, the PMMA index was used to assess the severity of sarcopenia based on muscle quantity.

The results showed that the PGS group had a significantly higher median PMMA index change than the non-PGS group (p = 0.004).

Specifically, the median value of the preoperative PMMA index in glutamine and non-glutamine groups was 4.9cm²​/m²​ and 5cm²​/m²​ (p = 0.850) respectively, while the median value of the three-month postoperative PMMA index in glutamine and non-glutamine groups was 5.6cm²​/m²​ and 5cm²​/m²​ (p < 0.001) respectively.

A multivariate analysis also revealed that PGS was significantly associated with increased PMMA index (p = 0.005).

“Our study serves as a pilot study with a large sample size to elucidate the clinical impact of PGS on surgical GA subjects. The results indicated that PGS helped restore the early postoperative atrophy of PMMA in these patients. ​

“The underlying mechanisms by which PGS contributes to the reduced atrophy may be related to glutamine’s role in enhancing nitrogen balance, protein metabolism and immune function. Further studies are needed to elucidate these mechanisms fully,” ​the researchers wrote.

Worsened by age​

According to the paper published on Nutrients​, individuals with advanced gastric cancer often suffer from malnutrition and sarcopenia.

Their condition tends to further deteriorate after surgery due to surgical stress and long-term consequences on the gastrointestinal system.

Glutamine has been proven in past studies to be a vital nutrient associated with tissue repair, protein metabolism, and maintenance of cell function.

It is present in high amounts in skeletal muscles, and can become conditionally essential when its synthesis is not enough to meet demand, such as in cancer patients or post-surgery.

In the current study, older age was significantly associated with early postoperative atrophy of PMMA, while those above 75 years showed a higher decrease in psoas muscle index.

“Muscular ageing is a complex physiological phenomenon involving a multifactorial origin in habits and lifestyle, and a decline in mitochondrial function in skeletal muscle and hormonal balance. This decline, upon reaching a pathological level, can lead to adverse outcomes.​

“Due to the increasing number of cancer treatments among the elderly, it is imperative to diagnose cachexia (wasting syndrome) early and implement effective interventions for improving health outcomes.” ​

It should be noted that this study has several limitations, including the lack of data on nutritional intake and physical activity, which may affect muscle mass.

“The definition of sarcopenia has evolved over time, but the most widely accepted definition today should take muscle quantity, muscle strength, and physical performance into consideration. Thus, there is a need for caution when using the psoas muscle index as a sole indicator of muscle health status, particularly across diverse populations or in complex clinical scenarios. ​

“We evaluated the association between PGS and short-term changes in the psoas muscle. Further studies, including randomised clinical trials, should be designed to validate our findings, uncover the molecular mechanisms, and the long-term effects of PGS supplementation.” ​

Source: Nutrients

https://doi.org/10.3390/nu16142301​

“Perioperative Glutamine Supplementation May Restore Atrophy of Psoas Muscles in Gastric Adenocarcinoma Patients Undergoing Gastrectomy” ​

Authors: Jin-Ming Wu, et al