Genotypic and phenotypic evaluation tissue-specific of alpha-linolenic bioconversion to eicosapentaenoic and docosahexaenoic fatty acids in rodents

• Grant number: 23/17562-3
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: September 01, 2024
• End date: February 29, 2028
• Field of knowledge: Health Sciences - Nutrition - Nutrition Biochemistry
• Principal Investigator: Dennys Esper Corrêa Cintra
• Grantee: Thaiane da Silva Rios
• Host Institution: Faculdade de Ciências Aplicadas (FCA). Universidade Estadual de Campinas (UNICAMP). Limeira , SP, Brazil

Abstract

Omega-3 fatty acids are essential once they are not endogenously synthesized in mammals, and their dietary intake is mandatory. These lipids are essential because they act as substrates for several secondary chemical mediators, membranes, organelles, and tissue constituents. The ±-linolenic acid (ALA - C18:3) is abundantly found in oil from seeds such as chia and linseed, however, its endogenous bioconversion to biologically more relevant species such as eicosapentaenoic acid (EPA - C20:5) and docosahexaenoic acid (DHA - C22:6) appears to be insufficient, and must be acquired from fish oils. The ALA can be bioconverted to EPA and DHA, but according to the literature, this process is ineffective. This claim is made by studies that, briefly, observe the concentration of EPA/DHA in the blood, after consumption of ALA. However, the bioconversion process occurs in tissues and, therefore, what is found in the blood would be a reflection of tissue production. In tissues, the key enzymes are desaturases and elongases, however, each tissue has a specific quantity and activity, apparently based on the use of each tissue. Therefore, assuming that the bioconversion rate of ALA to EPA/DHA is insufficient by observing the serum environment only before and after treatment with ALA seems to be unrealistic. While the literature indicates a conversion rate of up to 15% from ALA to EPA/DHA, preliminary data from our laboratory indicate a rate of up to 65% when this is observed in a specific tissue. The liver is the most investigated organ, however, other tissues have been neglected. Thus, the objective of this project is to evaluate the gene expression pattern of Fads1/2 and Elovls2/5/8, in addition to their protein content and activity in tissues such as liver, skeletal muscle, white and brown adipose tissue, testes and ovaries, hypothalamus, hippocampus and cerebellum, as well as the bioconversion pattern of ALA into EPA/DHA in these tissues and the blood, in healthy mice, in a time-dependent manner (0h, 3h, 6h, 12h and 24h) after supplementation. The hypothesis is that, if the rate of bioconversion in tissues is high, it will be understood that only the surplus of this production is released into the blood. If these findings are solid and if this hypothesis is observed in humans, in subsequent studies, this could change the current physiological understanding of the importance of these acids to the body, as well as serve as a basis for changing the standard of nutritional recommendations regarding such acids. fatty. Associated with this, it will be possible to reformulate nutritional strategies and food choices that prioritize plant sources to contribute to global sustainability. (AU)