A Randomized Placebo Controlled Clinical Trial to Determine the Impact of Digestion Resistant Starch MSPrebiotic® on Glucose, Insulin, and Insulin Resistance in Elderly and Mid-Age Adults

Abstract

Introduction: Type 2 diabetes (T2D) has reached epidemic proportions in North America. Recent evidence suggests that prebiotics can modulate the gut microbiome, which then plays an important role in regulating lipid metabolism, blood glucose, and insulin sensitivity. As such, prebiotics are appealing potential therapeutic strategies for prediabetes and T2D. The key objectives of this study were to determine the tolerability as well as the glucose and insulin modulating ability of MSPrebiotic® digestion resistant starch (DRS) in healthy mid-age (MID) and elderly (ELD) adults.

Materials and methods: This was a prospective, blinded, placebo-controlled study. Prediabetes and diabetes were among the exclusion factors. ELD (>70 years) and MID (30-50 years) Canadian adults were recruited and, after 2 weeks of consuming placebo, they were randomized to consume 30 g of either MSPrebiotic® or placebo per day for 12 weeks. In total, 42 ELD and 42 MID participants completed the study. Blood samples were collected over the 14-week study and analyzed for glucose, lipid profile, and CRP, lipid particles, TNF-α, IL-10, insulin, and insulin resistance (IR).

Results: At baseline, the ELD population had a significantly higher percentage (p < 0.01) with elevated glucose and significantly higher TNF-α (p < 0.01) compared to MID adults. MSPrebiotic® DRS was well tolerated in both MID and ELD adults. There was a significant difference over time in blood glucose (p = 0.0301) and insulin levels (p = 0.009), as well as IR (HOMA-IR; p = 0.009) in ELD adults who consumed MSPrebiotic® compared to placebo. No significant changes were found in MID adults.

Conclusion: Our results suggest that dietary supplementation with prebiotics such as MSPrebiotic® may be part of an effective strategy to reduce IR, a major risk factor for developing T2D, in the ELD.

Clinical trial registration: NCT01977183 listed on NIH website: ClinicalTrials.gov, The metadata generated in this study have been submitted to the NCBI Sequence Read Archive (http://www.ncbi.nlm.nih.gov/bioproject/381931).

Keywords: diabetes; digestion resistant starch; elderly; glucose; gut microbiome; insulin-resistance; prebiotics.

Figures

Figure 1

Flow chart of enrollment for the study. The elderly (ELD) enrollment is shown in (A) and the mid-age (MID) enrollment is shown in (B). (A) Consort 2010 flow diagram for ELD cohort. (B) Consort 2010 flow diagram MID cohort.

Figure 1

Flow chart of enrollment for the study. The elderly (ELD) enrollment is shown in (A) and the mid-age (MID) enrollment is shown in (B). (A) Consort 2010 flow diagram for ELD cohort. (B) Consort 2010 flow diagram MID cohort.

Figure 2

Tolerability of consuming MSPrebiotic® versus Placebo over time in elderly (ELD) and mid-age (MID) adults. All ELD (A–D) and MID (E–H) participants consumed 30 g placebo/day for 2 weeks and then were randomized to continue placebo or consume 30 g MSPrebiotic®/day for the remaining 12 weeks of the study. For abdominal pain, bloating and flatulence the scale was from 1 (none) to 5 (extreme). The red square symbols represent the placebo group, and the blue diamond symbols represent the MSPrebiotic® group. There was no statistically significant difference between groups for any of these parameters. (A) Abdominal pain ELD. (B) Bloating ELD. (C) Flatulence ELD. (D) Bowel movements per day ELD. (E) Abdominal pain MID. (F) Bloating MID. (G) Flatulence MID. (H) Bowel movements per day MID.

Figure 3

Impact of MSPrebiotic® versus placebo on mean blood glucose levels in the elderly (ELD) group. Placebo (30 g/day) was consumed by all participants for 2 weeks and then participants were randomized to continue on placebo (30 g/day) or to consume 30 g/day MSPrebiotic® for the next 12 weeks. Serum samples over the course of the study for the ELD group were analyzed on the day of collection for mean glucose levels. The black bars represent the placebo group and the white bars represent the MSPrebiotic® group. There was a significant group/time interaction for placebo versus MSPrebiotic® for the samples taken in week 0 compared to week 10 (8 weeks of consuming MSPrebiotic®) or week 14 (12 weeks of consuming MSPrebiotic®), p = 0.045 and p = 0.0124, respectively.