Serum concentration and mRNA expression of Transforming Growth Factor-Beta 1 (TGF-β1) in stunted and non- stunted toddlers

Abstract

Background and aims: West Nusa Tenggara Province has the fifth-highest prevalence of stunting cases in Indonesia. So far, limited research is available to understand the likelihood of stunting in this region. Transforming Growth Factor-Beta 1 (TGF-β1), an immunoregulatory cytokine, may affect the stunting progression. Knowledge of messenger mRNA expression in the TGF-β1 gene in stunted toddlers could help to determine therapeutic targets to catch up on their growth.

Objective: This study compared the expression of TGF- β1 mRNA and TGF-β1 concentrations in the stunted and the non-stunted toddlers. The nutritional status of all participants was also gathered and linked to the stunting issue.

Methods: A cross-sectional study was conducted on 48 toddlers aged 12-36 months. The stunting case was defined as a Z-Score of less than -2 of length/height for age according to WHO. The serum TGF-β1 and TGF-β1 gene mRNA were measured using ELISA and RT-PCR, respectively. The nutritional status data were collected through interviewer-administered structured questionnaire to the toddlers' parents and 48-h food recalls. Descriptive analyses were applied to determine the distribution of participants' macronutrient and micronutrient levels.

Results: Results show that there were significant differences in expressions of the TGF- β1 gene mRNA of the stunted and the non-stunted toddlers. The expression of the TGF- β1 mRNA gene in the non-stunted toddlers was also higher with 13.7 ± 0.859 fold change than those of the stunted toddlers with 9.01 ± 1.76 fold change with a p-value <0.001. The serum TGF-β1 concentrations in the stunted toddler (6.20 ± 3.60 pg/ml) were significantly lower than the ones in the non-stunted toddlers (14.3 ± 1.05 pg/ml) with p-value <0.001. However, there was no clear relationship between the likelihood of stunting and the nutritional status from the obtained data.

Conclusion: Overall findings demonstrate the significantly lower both the TGF-β1 gene mRNA expression and serum TGF-β1 for the stunted toddlers than the non-stunted toddlers, impacting bone formation and resorption. The outcomes of this study encourage the development of interventional therapy for stunted toddlers by increasing the serum TGF-β1 concentrations.

Keywords: Nutritional status; Serum TGF-β1 concentrations; Stunting; TGF-β1 gene mRNA expression.