Evaluation of polyunsaturated fatty acids content in the three stages of breast milk: colostrum, transitional and mature milk of a nursing mother submitted to Roux-en-Y gastric bypass surgery two months prior to pregnancy: Case study

The purpose of this case study was to investigate polyunsaturated fatty acids in colostrum, transitional milk and mature milk of a nursing mother attended to Roux-en-Y gastric bypass two months prior to pregnancy. For this, was collected 2ml (colostrum), 4ml (transitional milk) and 4ml (mature milk) samples obtained by manual expression of the breast that was not sucked in the last feeding, in the morning and placed in Eppendorfs-type microtubes. The fatty acid composition was performed by means of gas chromatography. The mean proportions of fat in colostrum, transition milk and mature milk were: eicosapentaenoic acid: 0.06%; 0.05% and 0.06%; docosahexaenoic acid: 0.12%, 0.08% and 0.09%; arachidonic acid: 0.58%, 0.37% and 0.42%, respectively; trans fatty from the industrial process: 0.11%,

recommendation for future work, it is suggested that research be carried out with a larger population undergoing such a procedure to investigate the composition of polyunsaturated fatty acids in breast milk. Keywords: Bariatric surgery; Human milk; Fatty acid.

Introduction
Currently, bariatric surgery (BS) is considered the most effective tool in the control and treatment of severe obesity (Zilberstein et al., 2019).
The main type of BS performed in Brazil, considered the gold standard, is the Roux-en-Y gastric bypass (RYGB) due to its safety and, mainly, its effectiveness (SBCBM, 2017).
Due to alteration of the gastrointestinal transit that impairs the pathways of absorption and/or food intake, post-BS nutritional deficiencies are common (Zaparolli, et al., 2018), both in the short and long term, which can cause severe clinical impacts (Ledoux, et al., 2020). According to Gascoin et al. (2017) micronutrient deficiencies increase after BS. Furthermore, exocrine pancreatic insufficiency is very common after RYGB (Uribarri-Gonzalez, et al., 2021). Forbes et al. (2016) investigated the impact of BS on essential fatty acid (EFA) status in non-pregnant women undergoing RYGB. However, no studies on quantify polyunsaturated fatty acids in colostrum, transitional milk and mature milk of a nursing mother with previous bariatric surgery were found.
The objective of the case study was to quantify polyunsaturated fatty acids in colostrum (COL), transitional milk (TM) and mature milk (MM) of a nursing mother submitted to Roux-en-Y gastric bypass two months prior to pregnancy.

Methodology
This article is a case study. According to Pereira et al. (2018), a case study is a description and analysis, as detailed as possible, of a case that presented some particularity that makes it special and can bring a wealth of data and information in order to contribute to knowledge in the area in the which one is used. In this type of study, patient can be seen as a case with its particularities.
In this study the patient signed the Free and Informed Consent Term to participate in the research and stated that she For the analysis of fatty acids (FAs), the techniques described by Folch et al. (1957) and Lepage & Roy (1986).
FAs methyl esters (FAME) were quantified on the Perkin Elmer Autosystem XL Chromatograph, as described in another study (Costa et al., 2011). FAs concentrations were expressed as the percentage of the total area comprising all FAs peaks (% of total FAME).
For statistical analysis, we estimated percentages, means and standard deviations.

Case Study
This is a 29-year-old woman who underwent Roux-en-Y gastric bypass (RYGB) two months prior to pregnancy.
At 30 weeks of gestation, she began receiving nutritional care at the Nutrition outpatient clinic of the IFF / Fiocruz. Table 1 shows maternal and newborn characteristics.

Results and Discussion
Analysis results of the composition (%) of polyunsaturated FAs in samples of COL, TM and MM of the nursing mother are shown in Table 2.  Due to the fact that we did not find studies that evaluated polyunsaturated fatty acids (PUFA) and long-chain polyunsaturated fatty acids (LC-PUFA) in BM of women who underwent BS, we compared the results with data available in the scientific literature of non-operated women.
BM is the food of choice for infants due to its ability to promote digestion and absorption of vitamins, the metabolic functions attributed to its ideal composition of linoleic acid (LNA), alpha-linolenic acid (ALA), arachidonic acid (ARA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which play an important role in optimal development.
Regarding ALA in the COL, Berenhauser et al. (2012) found a value like that found in our study. In a study carried out in Brazil, Freitas et al. (2019) found values of LNA and ALA in the MM higher than those found in our case report: LNA (13.90%) and ALA (1.04%). Berenhauser et al. (2012) also found higher ALA value in the MM: 0.86%. Castro et al. (2021), investigating the LNA content in BM, found in COL: 26.52%, TM: 22.34% and 22.26% in MM and ALA in COL: 1.71%, TM: 1 .12% and 1.57% in the MM, values much higher than those in our case report. This difference in results suggests that malabsorption of these lipids may have occurred, since BC significantly alters the dynamics of the digestive process. Exocrine pancreatic reserve is very common after RYGB (Uribarri-Gonzalez, et al., 2021).
Furthermore, studies show that, according to dietary, genetic, sociodemographic, health, and environmental factors and throughout the three stages of production: COL, TM, and MM, different types of milk are successively produced, with different compositions (Miliku, et al., 2019).
The ARA had the highest content in the COL phase and the lowest content in the TM and MM phases, which was also observed in the study by Castro et al. (2021).
In the present study, it was found that the concentration of EPA in the MM (0.06%) was lower than that observed in the study by Giufrida et al. (2022) and Castro et al. (2021) who found 0.32% and 0,17%, respectively. Miliku et al. (2019) found a content of 0.08% Regarding DHA, Castro et al. (2021) found much higher values than our report, 0.44% in COL, 0.30% in TM and 0.19% in MM. DHA content in breast milk reflects variations in maternal intake of this FA. Populations with a high intake of fish such as tuna, anchovies, sardines and salmon, among others, have a high content of this DHA in breast milk (Kim, et al., 2017).
Maternal adipose tissue can serve as a reservoir of PUFAs for BM as well as plasma which also supplies PUFAs to BM (Giufrida, et al., 2022). It should be noted that essential fatty acids (EFAs) are polyunsaturated fatty acids that must be obtained from the diet (Forbes, et al., 2016). If both adipose tissue and plasma PUFAs reflect dietary intake, it is necessary to provide these PUFAs during pregnancy or even before conception and lactation to ensure availability to mothers and sufficient supply to the baby via BM. Perhaps, the participant in this study had no reservations due to the lack of an adequate diet prior to pregnancy, due to common dietary errors in obesity, as well as nutritional deficiencies that occur due to the presence of food intolerances and/or changes in intestinal absorption after BS (Aguas-Ayesa, et al., 2023;Mechanick, et al., 2020). de la Garza Puentes et al. (2019) showed that breast milk of mothers with a high BMI presented decreased ALA and DHA concentrations than milk from normal weight nursing mothers. This finding corroborates what was observed in our study, when comparing the levels of ARA and DHA found in the BM samples of the nursing mother studied with that of Castro et al. (2021), who used COL, TM and MM samples from eutrophic women. It is important to point out that the nursing mother in the study was still in weight loss due to performing the BS only two months before the beginning of the pregnancy and presenting a nutritional diagnosis of overweight. Thus, our findings support the hypothesis that the nutritional status of the nursing mother influences the n-3 CL-PUFA lipid composition of MM.
It is noteworthy that DHA and ARA are present in the phospholipids of cell membranes and directly influence neuronal development, visual acuity and the baby's immune system (Freitas, et al., 2019).
There are two sources of TFAs in diets: industrial and ruminant (Costa, et al., 2016). Excessive consumption of TFA from industrialized foods by mothers can affect the growth and development of newborns, in addition to causing potential negative effects on metabolism by inhibiting the desaturation of LNA into ARA and ALA into DHA (Costa, et al., 2011).

Final Considerations
The relevance of this study case lies in the fact that it shares knowledge about on the fatty acid composition of BM from a nursing mother post RYGB. The mean LNA and ALA found in the MM was below the means found in studies carried out in Brazil from eutrophic women who did not underwent BS. In this study, TFAs were found in maternal milk but considered low values. The lack of other studies on the profile of PUFAs in the BM of women undergoing BS limited the comparison of the results found. As a relevant recommendation for future work, it is suggested that research be carried out with a larger population undergoing such a procedure to investigate the composition of polyunsaturated fatty acids in breast milk as well as analysis of maternal plasma phospholipids.