Appetite and Gut Hormones Response to a Putative α-Glucosidase Inhibitor, Salacia Chinensis, in Overweight/Obese Adults: A Double Blind Randomized Controlled Trial

Abstract

Animal studies indicate Salacia reduces body weight, possibly due to its α-glucosidase inhibitor (α-GI) properties, but this has not been examined previously. In this study, a randomized, placebo-controlled, three-way cross-over design was used to evaluate whether Salacia Chinensis (SC) reduces appetite in healthy overweight/obese individuals (body mass index 28.8 ±3.6 kg/m²; 32 ± 12 years). Forty-eight participants were fasted overnight and consumed a dose of SC (300 or 500 mg) or placebo with a fixed breakfast meal at each visit. Appetite sensations, glycemic indices and gastrointestinal peptides were measured. Results indicated that SC had no effect on postprandial appetite. However, in women, hunger was reduced by SC compared to placebo at multiple time points (300 mg; p < 0.05), but not in men. Area under the curve (AUC) for serum glucose, insulin and amylin was attenuated with SC compared to placebo (p < 0.05). Glucagon like peptide-1 had two peaks after the meal, but the AUC did not differ between groups. The AUC of peak areas for peptide YY and ghrelin were greater for SC than placebo (p < 0.05). These findings indicate that Salacia decreases glycemic indices supporting its role as an α-GI, and affects certain gastrointestinal peptides suggesting it may be an appetite modulator.

Keywords: Salacia Chinensis; appetite; gastrointestinal peptides; glycemic indices.

Conflict of interest statement

The authors declare no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analyses, interpretation of data or in the writing of the manuscript, and in the decision to publish the results.

Figures

Figure A1

Serum glucose (a), insulin (b), amylin (c), GLP-1 (d), PYY (e) and ghrelin (f) levels during 3 h after the mixed breakfast meal with a dose of SC or placebo. Abbreviations: glucagon-like peptide-1 (GLP-1), peptide YY (PYY), Salacia Chinensis extract (SC). * p < 0.05; ƚ p < 0.06, Differs from placebo. Values are means ± SEM. Placebo: ; 300 mg: ; 500 mg: .

Figure A2

Correlations of gut hormones (GLP-1, PYY) and prospective food consumption (PFC) at baseline, and after the meal with placebo or SC treatment (SC 300 mg, SC 500 mg) using area under the curve.

Figure 1

Flowchart of study participants. At each intervention, subjects were randomized in a double blind manner to placebo or one of two doses of treatment in a cross-over design.

Figure 2

Visual analogue scales (VAS) scores for hunger (a), fullness (b), satiety (c), and prospective food consumption (d) during 3 h after the mixed breakfast meal with a dose of Salacia Chinensis (SC) or placebo (n = 48). * p < 0.05, Differs compared to placebo. Values are means ± standard error of the mean (SEM). Placebo: ; 300 mg: ; 500 mg: .

Figure 3

VAS hunger scores during 3 h in age-matched females (a) and males (b). n = 32. * p < 0.05, Differs compared to placebo. Values are mean ± SEM. Placebo: ; 300 mg: ; 500 mg: .

Figure 4

Integrated area under the curve (AUC) for peak areas of glycemic indices (a) and gut hormones (b) after a mixed meal with either SC treatment compared to placebo. The AUC units are as follows: glucose (mg × min/dL); insulin (µIU × min/mL); and amylin/GLP-1/ PYY (pg × min/mL). * p < 0.05, Differs compared to placebo for glucose (×5), insulin, amylin, ghrelin (×0.5) and PYY. Placebo: ; 300 mg: ; 500 mg: .