Intraduodenal Administration of L-Valine Has No Effect on Antropyloroduodenal Pressures, Plasma Cholecystokinin Concentrations or Energy Intake in Healthy, Lean Men.
- 2019-01-05
- Nutrients 11(1)
- Rachel A Elovaris
- Penelope C E Fitzgerald
- Vida Bitarafan
- Sina S Ullrich
- Michael Horowitz
- Christine Feinle-Bisset
- PubMed: 30621276
- DOI: 10.3390/nu11010099
Study Design
- Type
- Randomized Controlled Trial (RCT)
- Population
- Twelve healthy lean men (age: 29 ± 2 years, BMI: 22.5 ± 0.7 kg/m²)
- Methods
- Randomised, double-blind order; 90-min intraduodenal infusions of L-valine at 0.15 kcal/min (total: 3.3 g) or 0.45 kcal/min (total: 9.9 g), or 0.9% saline (control)
- Blinding
- Double-blind
- Duration
- 90-min
- Rigorous Journal
Whey protein is rich in the branched-chain amino acids, L-leucine, L-isoleucine and L-valine. Thus, branched-chain amino acids may, at least in part, mediate the effects of whey to reduce energy intake and/or blood glucose. Notably, 10 g of either L-leucine or L-isoleucine, administered intragastrically before a mixed-nutrient drink, lowered postprandial blood glucose, and intraduodenal infusion of L-leucine (at a rate of 0.45 kcal/min, total: 9.9 g) lowered fasting blood glucose and reduced energy intake from a subsequent meal. Whether L-valine affects energy intake, and the gastrointestinal functions involved in the regulation of energy intake, as well as blood glucose, in humans, is currently unknown. We investigated the effects of intraduodenally administered L-valine on antropyloroduodenal pressures, plasma cholecystokinin, blood glucose and energy intake. Twelve healthy lean men (age: 29 ± 2 years, BMI: 22.5 ± 0.7 kg/m²) were studied on 3 separate occasions in randomised, double-blind order. Antropyloroduodenal pressures, plasma cholecystokinin, blood glucose, appetite perceptions and gastrointestinal symptoms were measured during 90-min intraduodenal infusions of L-valine at 0.15 kcal/min (total: 3.3 g) or 0.45 kcal/min (total: 9.9 g), or 0.9% saline (control). Energy intake from a buffet-meal immediately after the infusions was quantified. L-valine did not affect antral, pyloric (mean number; control: 14 ± 5; L-Val-0.15: 21 ± 9; L-Val-0.45: 11 ± 4), or duodenal pressures, plasma cholecystokinin (mean concentration, pmol/L; control: 3.1 ± 0.3; L-Val-0.15: 3.2 ± 0.3; L-Val-0.45: 3.0 ± 0.3), blood glucose, appetite perceptions, symptoms or energy intake (kcal; control: 1040 ± 73; L-Val-0.15: 1040 ± 81; L-Val-0.45: 1056 ± 100), at either load (p > 0.05 for all). In conclusion, intraduodenal infusion of L-valine, at loads that are moderately (3.3 g) or substantially (9.9 g) above World Health Organization valine requirement recommendations, does not appear to have energy intake- or blood glucose-lowering effects.
Research Insights
L-valine did not affect antral, pyloric ... or duodenal pressures
- Effect
- Neutral
- Effect size
- Small
- Dose
- 0.15 kcal/min (total: 3.3 g) or 0.45 kcal/min (total: 9.9 g), intraduodenally
L-valine did not affect ... appetite perceptions ... at either load
- Effect
- Neutral
- Effect size
- Small
- Dose
- 0.15 kcal/min (total: 3.3 g) or 0.45 kcal/min (total: 9.9 g), intraduodenally
L-valine did not affect ... blood glucose
- Effect
- Neutral
- Effect size
- Small
- Dose
- 0.15 kcal/min (total: 3.3 g) or 0.45 kcal/min (total: 9.9 g), intraduodenally
L-valine did not affect ... plasma cholecystokinin (mean concentration, pmol/L; control: 3.1 ± 0.3; L-Val-0.15: 3.2 ± 0.3; L-Val-0.45: 3.0 ± 0.3)
- Effect
- Neutral
- Effect size
- Small
- Dose
- 0.15 kcal/min (total: 3.3 g) or 0.45 kcal/min (total: 9.9 g), intraduodenally
L-valine did not affect ... duodenal pressures
- Effect
- Neutral
- Effect size
- Small
- Dose
- 0.15 kcal/min (total: 3.3 g) or 0.45 kcal/min (total: 9.9 g), intraduodenally
L-valine did not affect ... energy intake (kcal; control: 1040 ± 73; L-Val-0.15: 1040 ± 81; L-Val-0.45: 1056 ± 100)
- Effect
- Neutral
- Effect size
- Small
- Dose
- 0.15 kcal/min (total: 3.3 g) or 0.45 kcal/min (total: 9.9 g), intraduodenally
L-valine did not affect ... gastrointestinal symptoms ... at either load
- Effect
- Neutral
- Effect size
- Small
- Dose
- 0.15 kcal/min (total: 3.3 g) or 0.45 kcal/min (total: 9.9 g), intraduodenally
L-valine did not affect ... pyloric (mean number; control: 14 ± 5; L-Val-0.15: 21 ± 9; L-Val-0.45: 11 ± 4) ... pressures
- Effect
- Neutral
- Effect size
- Small
- Dose
- 0.15 kcal/min (total: 3.3 g) or 0.45 kcal/min (total: 9.9 g), intraduodenally