Clinical trial NCT04815122: Correlation Between COMT Val158Met Polymorphism and Dopaminergic Transporter Density (DAT) in Obese Women
Official title: Correlation Between the Presence of COMT Val158Met Polymorphism and Dopaminergic Transporter Density (DAT) in Obese Young Women
Study type: OBSERVATIONAL
Overall status: UNKNOWN
Conditions: Obesity
Keywords: Obesity
Genetic polymorphism
Dopamine
Lead sponsor: University of Sao Paulo
Sponsor class: OTHER
Collaborators: name: Fundação de Amparo à Pesquisa do Estado de São Paulo
First posted: 2021-03-24
Enrollment: 38
Sex: FEMALE
Minimum age (years): 20
Maximum age (years): 40
Standard ages: ADULT
Accepts healthy volunteers: no
Observational model: CASE_CONTROL
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Young women with obesity (BMI 30-35kg/m2), with and without COMT Val158Met polymorphism who participated in a previous study registered at clinicaltrials.gov (NCT02953353).

Brief summary: The present study aims to evaluate the correlation between the presence of COMT Val158Met polymorphism and the density of dopaminergic transporters (DAT) in young obese women.

Detailed description: The prevalence of obesity remains increasingly alarming in Brazil and worldwide. The most widely recommended therapy for obesity is lifestyle modification, however, implementing these changes that can lead to weight loss is difficult and maintaining a long-term weight loss is even more challenging. Consequently, an academic effort is required to understand the pathophysiology and treat obesity for the establishment of new approaches to reducing food intake.

Recent evidence in the field of obesity and brain-based integration indicates a potential for designing new therapeutic interventions. Noninvasive neuromodulation of brain activity has been shown to be a technique that can help reduce food cravings and food intake and, more recently, body weight, offering a new way to treat obesity. However, recent studies have shown that this biomedical intervention could have a paradoxical effect related to COMT Val158Met polymorphism, which impacts dopamine levels in the prefrontal cortex. The potential mechanisms underlying this effect are unclear and future studies are needed to promote this clarification.

This study aims to verify the influence of the COMT Val158Met polymorphism on the density of dopaminergic transporters in the presynaptic membrane of dopaminergic neurons, exploring the 3 dopaminergic pathways: via nigroestrital, mesolimbic and mesocortical. This investigation will be carried out through the cerebral SPECT using the radiopharmaceutical 99mTecnécio-TRODAT-1 in young obese women with and without COMT Val158Met polymorphism. In baseline conditions, the investigators will compare the SPECT 99mTc-TRODAT-1 of obese women with and without the COMT Val158Met polymorphism with a database of non-obese volunteers.

Our hypothesis is that the study will facilitate understanding of the variability of the individual response of carriers and non-carriers of the Met allele of the COMT Val158Met polymorphism, affecting dopamine levels in the brain and to design, in the future, for the treatment of obesity based on the individuals' genotypic differences.

Eligibility criteria: Inclusion Criteria:

* Women with obesity (BMI 30-35kg/m2), with and without COMT Val158Met polymorphism.

Exclusion Criteria:

* pregnancy
* any active psychiatric or neurological condition at the time of joining the study
* any other significant medical condition

Primary outcomes:
measure: Density of Dopaminergic transporters (DAT)
timeFrame: During the procedure
Secondary outcomes:
Other outcomes:
Locations:
city: Ribeirão Preto
country: Brazil
facility: Clinical Hospital of Ribeirão Preto Medical School
state: São Paulo
Study officials:
affiliation: University of Sao Paulo
name: Vivian MM Suen, MD, PhD
role: PRINCIPAL_INVESTIGATOR
affiliation: University of Sao Paulo
name: Lauro Winchert-Ana, MD, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Avsar O, Kuskucu A, Sancak S, Genc E. Are dopaminergic genotypes risk factors for eating behavior and obesity in adults? Neurosci Lett. 2017 Jul 27;654:28-32. doi: 10.1016/j.neulet.2017.06.023. Epub 2017 Jun 16.
citation: Barnett JH, Scoriels L, Munafo MR. Meta-analysis of the cognitive effects of the catechol-O-methyltransferase gene Val158/108Met polymorphism. Biol Psychiatry. 2008 Jul 15;64(2):137-44. doi: 10.1016/j.biopsych.2008.01.005. Epub 2008 Mar 14.
citation: Chen PS, Yang YK, Yeh TL, Lee IH, Yao WJ, Chiu NT, Lu RB. Correlation between body mass index and striatal dopamine transporter availability in healthy volunteers--a SPECT study. Neuroimage. 2008 Mar 1;40(1):275-9. doi: 10.1016/j.neuroimage.2007.11.007. Epub 2007 Nov 21.
citation: Fassini PG, Das SK, Suen VMM, Magerowski G, Marchini JS, da Silva Junior WA, Changyu S, Alonso-Alonso M. Appetite effects of prefrontal stimulation depend on COMT Val158Met polymorphism: A randomized clinical trial. Appetite. 2019 Sep 1;140:142-150. doi: 10.1016/j.appet.2019.05.015. Epub 2019 May 13.
citation: Fassini PG, Das SK, Magerowski G, Marchini JS, da Silva Junior WA, da Silva IR, de Souza Ribeiro Salgueiro R, Machado CD, Suen VMM, Alonso-Alonso M. Noninvasive neuromodulation of the prefrontal cortex in young women with obesity: a randomized clinical trial. Int J Obes (Lond). 2020 Jun;44(6):1279-1290. doi: 10.1038/s41366-020-0545-3. Epub 2020 Feb 19.
citation: Fonteneau C, Redoute J, Haesebaert F, Le Bars D, Costes N, Suaud-Chagny MF, Brunelin J. Frontal Transcranial Direct Current Stimulation Induces Dopamine Release in the Ventral Striatum in Human. Cereb Cortex. 2018 Jul 1;28(7):2636-2646. doi: 10.1093/cercor/bhy093.
citation: Horstmann A, Fenske WK, Hankir MK. Argument for a non-linear relationship between severity of human obesity and dopaminergic tone. Obes Rev. 2015 Oct;16(10):821-30. doi: 10.1111/obr.12303. Epub 2015 Jun 22.
citation: Van Laere K, De Ceuninck L, Dom R, Van den Eynden J, Vanbilloen H, Cleynhens J, Dupont P, Bormans G, Verbruggen A, Mortelmans L. Dopamine transporter SPECT using fast kinetic ligands: 123I-FP-beta-CIT versus 99mTc-TRODAT-1. Eur J Nucl Med Mol Imaging. 2004 Aug;31(8):1119-27. doi: 10.1007/s00259-004-1480-6. Epub 2004 Apr 3.
citation: Slifstein M, Kolachana B, Simpson EH, Tabares P, Cheng B, Duvall M, Frankle WG, Weinberger DR, Laruelle M, Abi-Dargham A. COMT genotype predicts cortical-limbic D1 receptor availability measured with [11C]NNC112 and PET. Mol Psychiatry. 2008 Aug;13(8):821-7. doi: 10.1038/mp.2008.19. Epub 2008 Mar 4.
citation: Volkow ND, Wang GJ, Telang F, Fowler JS, Thanos PK, Logan J, Alexoff D, Ding YS, Wong C, Ma Y, Pradhan K. Low dopamine striatal D2 receptors are associated with prefrontal metabolism in obese subjects: possible contributing factors. Neuroimage. 2008 Oct 1;42(4):1537-43. doi: 10.1016/j.neuroimage.2008.06.002. Epub 2008 Jun 13.
citation: Wang GJ, Volkow ND, Logan J, Pappas NR, Wong CT, Zhu W, Netusil N, Fowler JS. Brain dopamine and obesity. Lancet. 2001 Feb 3;357(9253):354-7. doi: 10.1016/s0140-6736(00)03643-6.