Circulating Spexin Levels Negatively Correlate With Age, BMI, Fasting Glucose, and Triglycerides in Healthy Adult Women

Abstract

ContextSpexin is a newly identified neuropeptide that is involved in satiety control, glucose, and lipids metabolism. It has also been related to human diseases, such as obesity and type 2 diabetes. However, whether spexin changes with age or not is still unclear.ObjectiveThe aim of this study is to investigate the relationship between circulating spexin levels and age and to study their interaction effects on body mass index (BMI), fasting glucose, and -lipids.Design and ParticipantsThis is a cross-sectional study, including 68 healthy adult women whose ages are in a wide range (minimum: 23; median: 38.5; maximum: 64).Outcome MeasuresThe serum spexin levels were measured by an enzyme-linked immunosorbent assay. Fasting glucose, total cholesterol, triglycerides (TG), alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, urea, and creatinine were measured by routine biochemical test. Shapiro-Wilk’s test, Spearman and Pearson correlation analyses, χ2 test, and two-way analysis of variance were used to interpret the data.ResultsSerum spexin levels are significantly correlated with age (Spearman r = −0.277, P = 0.022), BMI (Spearman r = −0.445, P < 0.001), fasting glucose (Spearman r = −0.302, P = 0.014), and TG (Spearman r = −0.324, P = 0.008). Spexin levels independently predict the risk of high BMI and high fasting glucose. No interaction effects of spexin and age on BMI and fasting glucose were found.ConclusionsCirculating spexin levels decrease with age, suggesting a possible role of this peptide in aging-related functions and disorders. Further investigations are needed to expand the clinical significance of this finding.

Serum Spexin is Correlated with Lipoprotein(a) and Androgens in Female Adolescents

“…Gu et al [12] in a study of adults with T2DM, found negative correlations for circulating spexin with blood lipids (LDL, TG). Lin et al [11] reported that spexin levels were significantly correlated with TG. Serum spexin concentrations correlated negatively with TG in obese children in the study of Chen et al [8].…”

“…Recent research by Kolodziejski et al [10] showed that serum spexin levels were reduced in obese women (vs. non-obese volunteers) and were negatively correlated with BMI, HOMA-IR and insulin. Lin et al [11] reported that spexin levels were negatively correlated with BMI, fasting glucose and with age suggesting a possible role of this peptide in aging-related functions and disorders. Likewise, Gu et al [12] reported lower circulating spexin levels in adults with type 2 diabetes mellitus (T2DM) as well as negative correlations of circulating spexin with blood glucose and hemoglobin A1c (HbA1c).…”

Emerging Roles of NPQ/Spexin in Physiology and Pathology

“…In vitro , the high level of insulin induced by glucose stimulated spexin gene expression in both goldfish hepatocytes and brain cells (Ma et al., 2017). Human study shows that the serum spexin was negatively correlated with age, BMI, fasting glucose, and TG in healthy adult women, suggesting that spexin could independently predict the risk of high BMI and high fasting glucose (Lin et al., 2018a). In human adipocytes and murine 3 T3-L1 cells, spexin exhibited a stimulatory effect on lipolysis and an inhibitory effect on lipogenesis and glucose uptake (Kolodziejski et al., 2018).…”

“…AgRP, agouti gene-related protein; ALT, alanine transaminase; AST, aspartate aminotransferase; BAAT, bile acid CoA: amino acid N-acyltransferase; BAs, bile acids; BMI, body mass index; CA, cholic acid; CART, cocaine-amphetamine regulated transcript; CCK, cholecystokinin; CDCA, chenodeoxycholate; CRH, corticotropin-releasing hormone; CYP27A1, sterol 27-hydroxylase; CYP7A1, cholesterol 7α-hydroxylase 1; CYP8B1, sterol 12α-hydroxylase; fshβ, follicle-stimulating hormone β; GalR2, galanin receptor 2; GalR3, galanin receptor 3; GCA, glycocholate; gh, growth hormone; gnih, gonadotropin inhibitory hormone; gnrh3, gonadotropin-releasing hormone 3; gthα, gonadotropin hormone α; HbA1c, hemoglobin A1c; HNF4α, hepatocyte nuclear factor 4 alpha; HS/NAFLD, hepatic steatosis/nonalcoholic fatty liver disease; KOR, κ-opioid receptor; LCFA, long-chain fatty acid; LDL-C, low-density lipoprotein-cholesterol; LH, luteinizing hormone; L-VDCC, L-type voltage-dependent calcium channel; MCH, melanin-concentrating hormone; NPY, neuropeptides Y; PCNA, proliferating cell nuclear antigen; Pdyn, prodynorphin; POMC, proopiomelanocortin; RER, respiratory exchange ratio; T2DM, type 2 diabetes mellitus; Tβ-MCA, tauro-β-muricholate; taut, taurine transporter gene; TG, triglyceride; TUDCA, tauroursodeoxycholate; ↑, increase; ↓, decrease; green arrow, promotion; red arrow, inhibition. (Partial figure originated from Lin et al., 2018a,b).…”

Evolution of Structural and Functional Diversity of Spexin in Mammalian and Non-mammalian Vertebrate Species

“…method and thus no effect is seen on the renal function. Recently, in addition to the proposed functional role of SPX in lipid metabolism, glucose homeostasis and insulin resistance, serum level of SPX was found to be decreased with age in healthy women investigated (38). This suggests that SPX could be involved in aging and its related disorders.…”