The Role of Catechol-O-Methyl Transferase Val(108/158)Met Polymorphism (rs4680) in the Effect of Green Tea on Resting Energy Expenditure and Fat Oxidation: A Pilot Study

Abstract

IntroductionGreen tea(GT) is able to increase energy expenditure(EE) and fat oxidation(FATox) via inhibition of catechol-O-methyl transferase(COMT) by catechins. However, this does not always appear unanimously because of large inter-individual variability. This may be explained by different alleles of the functional COMT Val108/158Met polymorphism that are associated with COMT enzyme activity; high-activity enzyme, COMTH(Val/Val genotype), and low-activity COMTL(Met/Met genotype).MethodsFourteen Caucasian subjects (BMI: 22.2±2.3 kg/m2, age: 21.4±2.2 years) of whom 7 with the COMTH-genotype and 7 with the COMTL-genotype were included in a randomized, cross-over study in which EE and substrate oxidation were measured with a ventilated-hood system after decaffeinated GT and placebo(PL) consumption.ResultsAt baseline, EE, RQ, FATox and carbohydrate oxidation(CHOox) did not differ between groups. Significant interactions were observed between COMT genotypes and treatment for RQ, FATox and CHOox (p<0.05). After GT vs. PL, EE(GT: 62.2 vs. PL: 35.4 kJ.3.5 hrs; p<0.01), RQ(GT: 0.80 vs. PL: 0.83; p<0.01), FATox(GT: 18.3 vs. PL: 15.3 g/d; p<0.001) and CHOox(GT: 18.5 vs. PL: 24.3 g/d; p<0.001) were significantly different for subjects carrying the COMTH genotype, but not for subjects carrying the COMTL genotype (EE, GT: 60.3 vs. PL: 51.7 kJ.3.5 hrs; NS), (RQ, GT: 0.81 vs. PL: 0.81; NS), (FATox, GT: 17.3 vs. PL: 17.0 g/d; NS), (CHOox, GT: 22.1 vs. PL: 21.4 g/d; NS).ConclusionSubjects carrying the COMTH genotype increased energy expenditure and fat-oxidation upon ingestion of green tea catechins vs, placebo, whereas COMTL genotype carriers reacted similarly to GT and PL ingestion. The differences in responses were due to the different responses on PL ingestion, but similar responses to GT ingestion, pointing to different mechanisms. The different alleles of the functional COMT Val108/158Met polymorphism appear to play a role in the inter-individual variability for EE and FATox after GT treatment.Trial RegistrationNederlands Trial register NTR1918

Long-Term Green Tea Extract Supplementation Does Not Affect Fat Absorption, Resting Energy Expenditure, and Body Composition in Adults

“…The latter may be explained by different single nucleotide polymorphisms of the functional COMT Val108/158Met polymorphism between ethnic groups, with a higher frequency of the high-activity enzyme, COMT H genotype (Val/Val polymorphism), in Asians and a higher frequency of the low-activity enzyme, COMT L genotype (Met/Met polymorphism), in Caucasians. This may play a role in the difference in sensitivity to GT with respect to energy expenditure and fat oxidation (35). Yet, within the present GT group the division between responders and nonresponders is similar to that in the placebo group, so this cannot be concluded from the present observation.…”

Antioxidants from black and green tea: from dietary modulation of oxidative stress to pharmacological mechanisms

“…Secondly, once ingested, they are extensively metabolized into molecules with different chemical structures and activity compared with the ones originally present in the teas. Therefore, differences in microbiota (van Duynhoven et al , ) and genetic polymorphism of metabolizing enzymes (Hursel et al , ) could play a role in the inter‐individual variability in the response to treatment. This implies that we must exercise caution when speculating about the effects of a cup of tea from in vitro data and results obtained in animals.…”

Influence of green tea catechins on oxidative stress metabolites at rest and during exercise in healthy humans

“…Further, it has been indicated that GTC effect on energy expenditure may possibly depend on genetic variability of COMT enzyme activity [45,46]. Influence of ethnicity on response to GTC supplementation has been suggested as a potential moderator for fat metabolism and energy expenditure [47], wherein it was postulated that different single nucleotide Val108/158Met polymorphism of the functional COMT may play a role in difference in sensitivity to GTC with respect to energy expenditure and fat oxidation [3,48]. Similar inference have been shown to increase 24 h noradrenalin urinary excretion M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT 23 following shorter term GTC intake at rest in human [14].…”