Effects of Chronic and Intermittent Calorie Restriction on Adropin Levels in Breast Cancer

Abstract

Adropin is a peptide hormone that has been implicated in insulin resistance and as a potential regulator of growth. The aim of this study is to determine the effect of calorie restriction on circulating levels of adropin in the MMTV-TGFα breast cancer mouse model and investigate the effects of adropin peptide on the viability of MCF-7 and MDA-231 breast cancer cells in culture. Ten-week-old mice were assigned to either ad libitum-fed (AL), chronic calorie-restricted, or intermittent calorie-restricted groups. Concentrations of serum adropin were measured using an enzyme-linked immunosorbent assay. Results showed an inverse correlation between serum adropin levels and mouse age that was attenuated by calorie restriction. In the AL group the level of adropin was significantly lower at week 50 compared to levels at week 10. However, among the calorie-restricted groups, serum levels of adropin remained high at week 50. The cell-line-specific effects were observed after treatment of cancer cell lines with a series of adropin concentrations (5, 10, 25, 50 ng/mL). Flow cytometry analysis showed that MCF-7 cells entered the early phase of apoptosis after treatment with 50 ng/mL for 24 h. Adropin may be involved in the protective effects that calorie restriction has on breast cancer risk.

Low plasma adropin concentrations increase risks of weight gain and metabolic dysregulation in response to a high-sugar diet in male nonhuman primates

“…The positive correlation between plasma adropin concentration and age in this study differs from previous results from humans and rodents showing a decline with aging (8,48,60,61). There are two potential explanations for the discrepancy that also serve as a precaution when comparing results between studies.…”

Serum Adropin and Adipose Fatty-Acid Binding Protein at 6th Week of Pregnancy Are Significant Predictors for Development of Insulin Resistance at the 24th Week.

“…However, against these data Gao et al (48) tried ADR treatment of diet-induced obesity with IR mice and found ADR treatment enhanced glucose tolerance, ameliorates IR and promotes preferential use of carbohydrate over fat in fuel selection and indicated a negative relationship between ADR level and high blood glucose level and IR; thus supporting the findings of the current study. Thereafter, Tuna et al (15) experimentally detected high serum ADR levels among animals received calorie-restricted diet, while was significantly lower among animals maintained on normal calorie intake, thus supporting the inverse correlation between serum ADR levels and calorie intake.…”

“…ADR is a 42-aminoacid peptide hormone which is highly conserved across mammalian species through open reading frame in exon 2 that encodes the full-length 75-amino acid peptide; 33-amino acid as secretory signal peptide and the biologically active ADR (13) . ADR is abundant in liver and secreted into the circulation and its plasma concentrations are highly regulated by energy intake (15) and functions to preserve the circulatory system through regulating endothelial function and activity of endothelial nitric oxide (16) .…”

Adropin as A Fat-Burning Hormone with Multiple Functions—Review of a Decade of Research

“…Therefore, GPR19 activation may promote carcinogenesis and metastases formation by promoting mesenchymal-to-epithelial cell transition. On the other hand, is was reported that adropin is able to suppress viability and induce apoptosis in the breast cancer MCF-7 cell line [64]. Thus, the role of adropin and its therapeutic potential in breast cancer is unclear and requires more experiments.…”