Effects of novel capsinoid treatment on fatness and energy metabolism in humans: possible pharmacogenetic implications.
BACKGROUND
Capsinoids from the Capsicum genus of plants are nonpungent capsaicin-related substances with effects on metabolism and body weight in animals.


OBJECTIVE
Our objectives were to explore the safety and efficacy of capsinoids taken orally (6 mg/d) for weight loss, fat loss, and change in metabolism and to examine whether candidate genes are predictors of capsinoid response.


METHODS
This was a 12-wk, placebo-controlled, double-blind, randomized study. Eligibility criteria included a body mass index (BMI; in kg/m(2)) of 25-35. Body weight was measured, and dual-energy X-ray absorptiometry, indirect calorimetry (men only), and genotyping were conducted.


RESULTS
Forty women and 40 men with a mean (+/- SD) age of 42 +/- 8 y and BMI of 30.4 +/- 2.4 were randomly assigned to a capsinoid or placebo group. Capsinoids were well tolerated. Mean (+/- SD) weight change was 0.9 +/- 3.1 and 0.5 +/- 2.4 kg in the capsinoid and placebo groups, respectively (P = 0.86). There was no significant group difference in total change in adiposity, but abdominal adiposity decreased more (P = 0.049) in the capsinoid group (-1.11 +/- 1.83%) than in the placebo group (-0.18 +/- 1.94%), and this change correlated with the change in body weight (r = 0.46, P < 0.0001). Changes in resting energy expenditure did not differ significantly between groups, but fat oxidation was higher at the end of the study in the capsinoid group (least-squares mean difference: 21.0 mg/min; P = 0.06). Of 13 genetic variants tested, TRPV1 Val585Ile and UCP2 -866 G/A correlated significantly with change in abdominal adiposity.


CONCLUSIONS
Treatment with 6 mg/d capsinoids orally appeared to be safe and was associated with abdominal fat loss. Capsinoid ingestion was associated with an increase in fat oxidation that was nearly significant. We identified 2 common genetic variants that may be predictors of therapeutic response.
Snitker
Soren
S
University of Maryland School of Medicine, Baltimore, MD 21209, USA. ssnitker@medicine.umaryland.edu
Fujishima
Yoshiyuki
Y
Shen
Haiqing
H
Ott
Sandy
S
Pi-Sunyer
Xavier
X
Furuhata
Yasufumi
Y
Sato
Hitoshi
H
Takahashi
Michio
M
D050153:Abdominal Fat / Q000187:drug effects* / Q000378:metabolism; D015502:Absorptiometry, Photon / Q000379:methods; D000273:Adipose Tissue / Q000187:drug effects* / Q000378:metabolism; D000328:Adult; D019440:Anti-Obesity Agents / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D001823:Body Composition / Q000187:drug effects / Q000502:physiology; D015992:Body Mass Index; D002153:Calorimetry, Indirect / Q000379:methods; D002211:Capsaicin / Q000031:analogs & derivatives / Q000494:pharmacology; D002212:Capsicum / Q000737:chemistry*; D004038:Diet, Reducing; D019587:Dietary Supplements; D004311:Double-Blind Method; D004734:Energy Metabolism / Q000187:drug effects* / Q000502:physiology; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D008297:Male; D009765:Obesity / Q000178:diet therapy / Q000188:drug therapy* / Q000235:genetics; D010084:Oxidation-Reduction; D010101:Oxygen Consumption / Q000502:physiology; D010936:Plant Extracts / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D016896:Treatment Outcome
D019440:Anti-Obesity Agents; D010936:Plant Extracts; D002211:Capsaicin