Favorable Changes in Fasting Glucose in a 6-month Self-Monitored Lifestyle Modification Programme Inversely Affects Spexin Levels in Females with Prediabetes

Abstract

Spexin (SPX) is a novel peptide thought to have a role in various metabolic regulations. Given its presumed body-weight regulatory functions, we aimed to determine whether lifestyle intervention programs on weight loss and fasting glucose (FG) improvement among people with impaired glucose regulation also alter levels of circulating SPX. A total of 160 Saudi adult males and females with prediabetes were randomly selected from a larger cohort (N = 294) who underwent a 6-month lifestyle modification program to improve their glycemic status. Participants were split into two groups based on differences in glucose levels post-intervention, with the first 50% (improved group) having the most significant reduction in FG. SPX was measured at baseline and after 6 months. Changes in SPX was significant only in the improved group [baseline: median (Q1-Q3) of 164 pg/ml (136-227) vs follow-up: 176 pg/ml (146-285); p < 0.01]. When stratified by sex, the significant increase was observed only in females [159 pg/ml (127-252) vs 182.5 (152,369.1); p < 0.01]. Furthermore, SPX levels showed a significant inverse association with FG (β = -0.22, p = 0.003) even after adjustment with age and BMI, again only in females. Circulating SPX levels increase over time in people with prediabetes, particularly women who responded favorably in a 6-month lifestyle intervention program. Whether an unknown mechanism regulating the sexual disparity seen in SPX levels post-intervention exists should be further investigated using a larger sample size.

Figure 1

Changes in levels of fasting glucose and spexin overtime. Data presented as Mean ± SD for fasting glucose (A) and median (25th percentile, 75th percentile) for SPX (B). NG and IG represent non-improved and improved groups respectively while F and M represents females and males respectively. **Depicts p-value < 0.01.

Figure 2

Association of spexin with glycemic indices. Fasting glucose (A), insulin (B) and HOMA-IR (C) on X-axis and spexin on Y-axis. Significant inverse correlations between SPX and glycemic indices were seen only in females. “r” depicts pearson correlation coefficient and “p” is the associated p-value. P-value < 0.05 is considered significant.

Figure 3

Study Flowchart.