Saturated Fatty Acids Research Articles

Differential fatty acids utilization across life stages in a Vespa species.

Dietary fatty acids (FAs) are essential macronutrients affecting animal fitness, growth, and development. While the degree of saturation of FAs usually determines the level of absorption and allocation within the body, the utilization of dietary FAs across the life stages of individuals remains unknown. We used three different 13C labeled FAs, with a different saturation level (linoleic acid (18:2), oleic acid (18:1), and palmitic acid (16:0)), to investigate the absorption and allocation of dietary FAs across the life stages of the Oriental hornet. Our results show that only larvae utilized all tested FAs as metabolic fuel, with palmitic acid being oxidized at the highest rate. Oleic and palmitic acids were predominantly incorporated into larval tissues, while oleic acid dominated pupal tissues. In contrast, linoleic and oleic acids were predominantly incorporated into adult tissues. These findings highlight a life stage-dependent shift in certain FAs utilization, with palmitic acid mostly utilized in early stages and linoleic acid in adulthood, while oleic acid remained consistently utilized across all life stages. This study emphasizes the importance of considering FA saturation and life stage dynamics in understanding FA utilization patterns.

The Synergistic and Opposing Roles of ω-Fatty Acid Hydroxylase (CYP4A11) and ω-1 Fatty Acid Hydroxylase (CYP2E1) in Chronic Liver Disease

Cytochrome P450 fatty acid hydroxylase consists of members of the CYP4 family that ω-hydroxylate fatty acids and the CYP2E1 that ω-1 hydroxylates fatty acids. Although ω and ω-1 hydroxylation of fatty acids have been thought to play a minor role in fatty acid metabolism (less than 20%), it plays a vital role in excess liver fatty acids overload seen in fasting, diabetes, metabolic disorder, and over-consumption of alcohol and high-fat diet. This pathway provides anabolic metabolites for gluconeogenesis, succinate, and acetate for lipogenesis. The CYP4A and CYP2E1 genes are activated in fasting and several metabolic disorders, suggesting a synergistic role in preventing fatty acid-induced lipotoxicity with the consequence of increased liver cholesterol and lipogenesis leading to increased Lipid Droplet (LD) deposition. During the progression of Metabolic Dysfunction-associated Steatotic Liver Disease (MASLD), activation of Phospholipase A2 (PLA2) releases arachidonic acid that CYP4A11 and CYP2E1 P450s metabolize to produce 20-hydroxyeicosatetraenoic acid (20-HETE) and 19-HETE, respectively. These metabolites have opposing roles in the progression of MASLD and chronic liver disease (CLD). This report discusses the synergistic role of the CYP4A and CYP2E1 P450s in the metabolism of saturated and unsaturated fatty acids and their opposite physiological role in the metabolism of Arachidonic Acid (AA). We finally discuss the role of ethanol in disrupting the synergistic and opposing roles of the CYP4A and CYP2E1 genes in MASLD and CLD.

Pelargonic acid’s interaction with the auxin transporter PIN1: A potential mechanism behind its phytotoxic effects on plant metabolism

Pelargonic acid (PA) is a saturated fatty acid commonly found in several organisms, that is known for its phytotoxic effect and its use as bioherbicide for sustainable weed management. Although PA is already commercialised as bioherbicide, its molecular targets and mode of action is unknown according to the Herbicide Resistance Action Committee. Therefore, the aim of this work was focusing on the way this natural active substance impacts the plant metabolism of the model species Arabidopsis thaliana. PA caused increase of secondary and adventitious roots, as well as torsion, loss of gravitropism and phytotoxic effects. Moreover, PA altered the cellular arrangement and the PIN proteins activity. Computational simulations revealed that the intermolecular interactions between PA and the polar auxin transporter protein PIN1 are very similar to those established between the natural auxin IAA and PIN1. However, under intracellular conditions, the PA-PIN1 binding is more energetically stable than the IAA-PIN1. These results suggest that PA could act as an auxin-mimics bioherbicide. The exogenous application of PA would be responsible for the alterations observed both at structural and ultrastructural levels, which would be caused by the alteration on the transport of auxins into the plant, inducing root inhibition and ultimately total stop of root growth.

Systemic immune-inflammation states in US adults with seropositivity to infectious pathogens: A nutrient-wide association study.

Limited understanding exists regarding the association between daily total dietary nutrient intakes and immune-inflammation states in US adults exposed to various pathogens. This study sought to examine the correlation between nutrient intakes and immune-inflammation indicators and to assess their performance in distinguishing immune-inflammation states. This study was derived from the National Health and Nutrition Examination Survey (NHANES), which included 33,804 participants aged 20 years or older between 2005 and 2018. Multivariable linear regression and restricted cubic spline regression were conducted to evaluate the association between nutrient intakes and immune-inflammation indicators. Receiver operating characteristic curve analysis was performed to evaluate the discriminatory performance of identified nutrients for various immune-inflammation states measured by the systemic immune-inflammation index (SII). Ten key nutrients were significantly associated with immune-inflammation responses, including calcium, saturated fatty acid (SFA) 4:0, SFA 6:0, SFA 12:0, SFA 14:0, SFA 16:0, vitamin B2, total SFAs, retinol, and lutein + zeaxanthin, which show potential as dietary indicators. The area under the curve for discriminating various immune-inflammation states was improved by at least 0.03 compared with a model that included only covariates, with all P values <0.05 in the Delong tests, indicating a significant enhancement in model performance. Ten nutrients, including calcium, various SFAs, vitamin B2, retinol, and lutein + zeaxanthin, exhibit significant association with SII and potential as dietary indicators for distinguishing between different immune-inflammation states in US adults with seropositivity to various viruses.

Nutritional properties of pilot-scale manufactured single-cell proteins from a Corynebacterium glutamicum

ABSTRACT Single-cell proteins (SCPs) derived from microorganisms are sustainable and standard-manufacturable protein sources. Corynebacterium glutamicum is one of the prospective bacteria for SCP production. To evaluate nutritional properties of C. glutamicum-SCP, pilot-scale fermentation (3,000 L) was performed under standard conditions, resulting in 23 kg of SCP in dry weight. This C. glutamicum-SCP had high protein and low-fat contents (22.4% carbohydrates, 60.9% crude protein, and 3.3% crude fat). Its fatty acid profile comprised 0.25% saturated fatty acids, 0.16% unsaturated fatty acids, no trans fatty acids, and no cholesterol. Its total iron content was 9.78 mg/100 g, of which approximately 14.8% was heme iron (1.45 mg/100 g). The Digestible Indispensable Amino Acid Score (DIAAS) of C. glutamicum-SCP was 102, higher than that of soy protein isolate (90), pea protein concentrate (82), house cricket (89), or yellow mealworm (64). In conclusion, C. glutamicum-SCP can be a promising alternative protein source to replace red meat.

Exploring the impact of fatty acid composition on carcass and meat quality in Bos taurus indicus influenced cattle.

The study of fatty acid (FA) and mineral content in beef is crucial for bridging health and taste. Understanding these components is essential for catering to consumer preferences for nutritious and tasty food, in line with current dietary trends and health recommendations. This holistic view of beef quality is key to helping both producers and consumers make more knowledgeable and health-oriented decisions in meat consumption. The objectives of this study were to 1) characterize the FA composition and mineral concentration of beef from Brangus cattle; 2) estimate their heritability; and 3) calculate the genetic and phenotypic correlations of carcass and meat quality traits to FA composition and mineral concentrations. Brangus steers were evaluated for meat quality and sampled for nutritional content measurements. Brangus cattle had palmitic acid levels as low as 21%, and stearic acid levels as high as 26%, which is notable since stearic acid is considered to have a neutral or potentially beneficial impact on cholesterol levels, unlike other saturated fats. Additionally, Brangus cattle had oleic acid levels as high as 53%, a beneficial monounsaturated fat, and linoleic acid concentrations as high as 12%, an essential omega-6 FA. Saturated FA showed weak negative correlations (-0.06 to -0.15) with hot carcass weight, marbling, and fat over ribeye, similar to polyunsaturated FA which had moderate negative correlations (-0.19 to -0.37) with these traits. Conversely, monounsaturated FA was positively correlated (0.16 to 0.34) with these traits, suggesting that higher levels of monounsaturated FA, particularly oleic acid, are associated with improved meat quality and consumer-desirable traits such as increased marbling. This relationship where higher marbling is linked with increased monounsaturated FA and decreased saturated FA is unique in Brangus cattle, differing from other breeds where increased intramuscular fat typically raises FA saturation levels. The variation in FA observed in Brangus cattle highlights the breed's potential to provide nutritionally enriched beef. With selective breeding, it may be possible to improve both the nutritional value and marbling of the meat, meeting consumer demand for healthier, tastier options. Overall, the study underscores the intricate relationships between FA composition, mineral content, and meat quality, with implications for breeding and nutrition strategies aimed at improving meat quality and healthfulness.

Application of Pyroligneous Acid as a Plant Growth Stimulant Can Improve the Nutritional Value of Soybean Seed

Farmers today are using biochemical treatments to improve their crop yields. Commercialized organic biostimulants exist in the form of pyroligneous acid generated by burning agricultural waste products. During the 2023 growing season, we demonstrated that soil treatment with a commercial pyroligneous acid product, Coriphol™, manufactured by Corigin Solutions, Inc., stimulated plant growth and significantly improved yield with an optimal treatment dose of 2 gal. acre−1. In the present work, we examined the effect of this treatment on soybean nutritional content using seed harvested from the 2023 season. Total mean seed protein content for untreated control plants was 32.26 ± 0.49% of dry mass and increased 10.8% to 35.64 ± 0.64% with treatment. This increase resulted in a net reduction in total free amino acid content, although levels of the essential dietary amino acid, lysine, were boosted 6-fold. Total lipid content was unaffected by treatment with mean levels of 21.61 ± 0.70% of dry mass noted. Treatment, however, reduced saturated fatty acid content by roughly 40%, and reduced the polyunsaturated content of linoleic acid in favor of the monounsaturated fatty acid, oleic acid. Finally, Coriphol™ treatment did not impact seed content of eight essential micronutrients including Na, Mg, K, Ca, Fe, Ni, Cu, and Mo, but did significantly boost Zn and Mn levels. Altogether, these results demonstrate that soil treatment with the growth stimulant Coriphol™ has the potential to improve the dietary nutritional value of soybean.

Transesterification of waste cooking oil for biodiesel production using alkaline-modified graphitic carbon nitride heterogeneous catalyst

ABSTRACT Developing efficient, stable, cost-effective, and environmentally benign heterogeneous catalysts for transesterification is highly required for sustainable biodiesel production. The present study explores the biodiesel production from waste cooking oil (WCO) using graphitic carbon nitride (g-C3N4) and its alkaline-modified nanocatalyst. The catalysts were characterised by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Energy Dispersive X-ray spectroscopy (EDS), and Fourier transform infrared spectroscopy (FTIR). From the XRD analysis, crystalline sizes of g-C3N4 and alkaline g-C3N4 were found to be 26 and 29 nm, respectively. Transesterification of WCO was carried out at 60 °C for a reaction time of 2 h using 2 wt.% of g-C3N4 and alkaline g-C3N4. Transesterification reaction catalysed by alkaline-modified g-C3N4 was found with a higher yield of biodiesel (89%) than the biodiesel yield (78%) with transesterification reaction catalysed by g-C3N4. The recyclability of both catalysts was also evaluated by reusing them for up to the 5th cycle. The obtained biodiesel was analyzed by using FTIR and GC-MS. The synthesised biodiesel was found to have significant level of monounsaturated fatty acids and saturated fatty acids, which make it usefuel for use as fuel. Some physicochemical properties of the obtained biodiesel were also calculated and found appropriate as per the American Society for Testing and Materials (ASTM) standards. With high reusability and good catalytic activity, the synthesised alkaline-modified g-C3N4 can be employed as a viable option for biodiesel production from WCO.

Effect of climatic factors on sexual maturity Labeo rohita fish

&lt;p&gt;This study examined the varying levels of thyroxine hormone impact (at doses of 2, 10, and 50 µg g-1 BW) as an environmentally responsive hormone on the fatty acid and sexual steroid profiles in male Labeo rohita fish. Each treatment group comprised six male fish with an average weight of 5.4 ± 0.58 kg. Blood samples were collected from male rohu fish pre-and post-injection, as well as following sperm retrieval from the caudal peduncle. Biotechnical parameters were evaluated post-fertilization. Among male breeders, the pituitary treatment and the 50 µg g-1 BW thyroxine treatment exhibited the highest levels of estradiol, testosterone, 17-alpha hydroxyprogesterone, cortisol, LH, as well as testicular protein and fat content. Whereas the lowest levels were observed in the LHRH recipient and control groups (p &amp;lt; 0.05). Moreover, the saturated fatty acids C16:0 and C18:0, monounsaturated fatty acids C18:1n9c and C24:1n9, along with polyunsaturated fatty acids C20:3n6 and C22:6n3 in male breeders, were found to be the predominant fatty acids in the testes under hormonal treatment. The pituitary treatment and the 50 µg g-1 BW thyroxine treatment demonstrated a greater total percentage of testicular fatty acids compared to other interventions (p &amp;lt; 0.05). These findings emphasize the heightened efficacy of pituitary hormone and subsequent thyroxine hormone administration at a dose of 50 µg g-1 BW, relative to lower thyroxine doses and LHRH. The aforementioned treatment can increase the levels of sex hormones that are important for sexual responsiveness, emphasizing their pivotal role in facilitating successful artificial reproduction in male Rohu breeders.&lt;/p&gt;

The association between circulating saturated fatty acids and thyroid function: results from the NHANES 2011-2012.

Excessive saturated fatty acids (SFAs) are known to be detrimental to human health. Although the majority of research and dietary guidelines have focused on the intake of SFAs, there has been limited attention to the relationship between circulating SFA levels and hormonal regulation, such as that of thyroid hormones. To explore potential associations, we conducted an investigation with 579 participants from the National Health and Nutrition Examination Survey (NHANES) 2011-2012. Subgroup analyses and multivariable linear regression models were used to estimate the relationships between eleven distinct SFA concentrations and various thyroid parameters. For 579 adults, subgroup analysis of thyroid stimulating hormone (TSH) revealed significant differences in nine specific SFAs and the total SFA levels (all p < 0.05). Furthermore, multivariable linear regression analysis identified positive correlations between certain SFAs and various parameters, including TSH, total triiodothyronine (TT3), free triiodothyronine (FT3), thyroid peroxidase antibodies (TPOAb), thyroglobulin antibodies (TgAb), thyroglobulin (Tg), the ratio of FT3 to free thyroxine (FT4) (FT3/FT4), and the thyrotroph T4 resistance index (TT4RI). Conversely, negative correlations were observed between certain SFAs and total thyroxine (TT4), FT4, the ratio of FT3/TT3, and the thyroid feedback quantile-based index (TFQI) (all p < 0.05). These findings collectively suggest associations between SFAs and thyroid parameters, highlighting the need for future studies to elucidate the underlying mechanisms of these interactions.

Assessment of dietary intake in patients with metabolic dysfunction-associated steatotic liver disease using the Ukrainian version of the EPIC-Norfolk Food Frequency Questionnaire: A cross-sectional study

Metabolic dysfunction‑associated steatotic liver disease (MASLD) is prevalent worldwide. Studies demonstrate a possible association between diet and MASLD. However, data regarding patients in Ukraine are lacking. Objective — to study dietary habits and meeting recommended dietary intake in patients with MASLD. Materials and methods. Adults with MASLD aged 18 years and older (n=29) receiving care in outpatient settings who fully completed the adapted and validated Ukrainian version of the EPIC‑Norfolk Food Frequency Questionnaire (FFQ) were included in the analysis. Liver steatosis was confirmed by ultrasound examination, and diagnosis of MASLD was based on the criteria defined by the American Association for the Study of Liver Diseases. As a reference for recommended dietary intake, data from the Dietary Guidelines for Americans, 2020—2025 years were used. FETA software was used to calculate nutrient data from the FFQ. The one‑sample t‑test, t‑test, the one‑sample signed rank sum test, and Mann‑Whitney test were used to assess the differences between the sample and the reference data. The chi‑squared test was used to analyse categorical data. Results. The mean age of participants was 41.4±12 years, 69% of participants being female. The mean body mass index was 35.4±7.9 kg/m2. Participants consumed more protein, than recommended by current dietary recommendations. Women also tended to have higher energy intake and consume more fat, saturated fatty acids, and carbohydrates than recommended. The median fibre intake was 19.36 g (Q1; Q3 : 13.29; 26.45), which is lower than the recommended 14 g per 1000 kcal (p=0.0015). Dietary intake of most vitamins and micronutrients was met. However, women and men consumed less than 600 IU of vitamin D daily. Among all patients with MASLD, sodium intake (3829.5±1559.3 mg) was significantly higher than recommended (2300 mg, p&lt;0.0001). Approximately 62% of participants take dietary supplements, with vitamin D being the most popular choice. Conclusions. Our study showed that patients with MASLD in Ukraine tend to exceed recommended protein and sodium intake and, at the same time, have low fibre and Vitamin D consumption. High energy intake and saturated fatty acids consumption are also of concern.

Growth performance, carcass characteristics, fatty acid profile, and meat quality of male goat kids supplemented by alternative feed resources: bitter vetch and sorghum grains

Abstract. Bitter vetch and sorghum grains are alternative local feed resources that are underutilized in the southern Mediterranean area. This study aimed to assess the effects of incorporating these grains into the diet of local goat breeds on growth performance, carcass characteristics, and meat quality. Twenty-four goat kids were divided into three groups. The control group received a conventional diet consisting of oat hay, barley, and fava beans. In the first group, fava beans were replaced with bitter vetch, and in the second group, barley was replaced with sorghum. At the end of the trial, the animals were slaughtered and carcass characteristics and meat fatty acid profiles of the longissimus dorsi (LD) muscle were determined. Alternative grain incorporation had no significant effect on the growth parameters. Still, it significantly affected carcass characteristics, especially in the sorghum group compared to the control group, where mesenteric fat was lower (266 vs. 437 g). The back color was lighter (L*=55.1 vs. 59.1) and less yellow (a*=-1.29 vs. 2.22). The diet also influenced the meat's chemical composition, with less protein and ash in the chevrons of animals receiving bitter vetch and sorghum grains, respectively. Regarding the fatty acid (FA) profile, sorghum grains had decreased C18:2 n-6 and polyunsaturated FA (PUFA), whereas bitter vetch grains had increased C18:3 n-3, elongase activity, and nutritive value index (NVI). The control group exhibited intermediate results for C15:0, C16:0, C16:1, C20:3 n-3, n-3, health promoting index (HPI), and thrombogenic index (TI). No significant effects were reported for saturated FA (SFA) and monounsaturated FA (MUFA). Bitter vetch and sorghum grains can be safely incorporated into fattening diets of goat kids.

The role of short-chain fatty acid metabolism in the pathogenesis, diagnosis and treatment of cancer.

Short-chain fatty acids (SCFAs), which are saturated fatty acids consisting of six or fewer carbon atoms, have been found to be closely associated with the biological behavior of malignant tumors. This manuscript provides a comprehensive review on the role of SCFAs in regulating cell cycle, apoptosis, tumor angiogenesis, epithelial-mesenchymal transition, protein regulatory pathways, and histone regulation in promoting the development of malignant tumors. Furthermore, we discuss the potential therapeutic strategies targeting SCFAs for treating malignant tumors. This review offers a theoretical foundation for investigating the mechanisms by which SCFAs impact malignant tumors and provides insights into developing novel treatment targets.

The effect of increasing canola oil and soybean oil addition to beef cattle rations based on corn silage and barley grain on the in vitro ruminal gas production and rumen fermentation

AbstractThe purpose of the current experiment was to determine the effects of ruminal fermentation parameters of the additions of canola or soybean oils at different rates (4, 8 and 12%) to beef cattle total mix rations (TMR), based on corn silage and barley grain. The addition of 4% soybean oil to TMR positively affected in vitro gas production, net energy lactation (NEL), metabolic energy (ME), and organic matter digestion (OMd). The additions of 8% and 12% of soybean oil to TMR linearly decreased ME, NEL and OMd (p &lt; 0.05). The additions of 4, 8 and 12% canola oil to the TMR linearly decreased the in vitro gas production and estimated fermentation values (ME, NEL and OMd) (p &lt; 0.05). All doses of soybean or canola oils in TMR reduced the molarities of total short‐chain fatty acids (tSFCA), acetic (AA), butyric (BA), propionic (PA), valeric (VA), iso‐valeric (IVA) and iso‐butyric acids (IBA) for in vitro fermentation fluid (p &lt; 0.05). There was a negative correlation between the increasing dietary stearic, oleic and linoleic acid and the end‐products of in vitro rumen fermentation. However, increasing dietary α‐linolenic acids had no adverse effect on in vitro ruminal fermentation end‐products. As a result, 4% addition of the soybean oil, which included a higher rate of α‐linolenic acid and saturated fatty acids and a lower rate of oleic, linoleic acids according to those of canola oil, to the TMR positively affected in vitro ruminal fermentation. In addition, the ≥8% addition of canola or soybean oil adversely affected the in vitro fermentation values.

Comparison of Growth and Composition of Black Soldier Fly (Hermetia illucens L.) Larvae Reared on Sugarcane By-Products and Other Substrates.

Black soldier fly larvae (BSFL) can convert organic waste into high-quality biomass. In this study, we tested the potential of sugarcane by-products as a food source for BSFL and compared larval development and nutritional value with some other organic substrates. Seven different substrates were used, including carrot pomace (C), carrot pomace and leftover bread (CB) (50/50), bagasse and vinasse (BV), bagasse and molasses (BM), bagasse, vinasse, and molasses (BVM), a mixture of all the above treatments (MX), and university canteen leftovers (UCLs). The larval weight and length were measured for two weeks from day 5 to 19. Then, the BSFL were harvested and analyzed for dry matter, crude protein, oil, ash, mineral, and fatty acid composition. Larval weight and length varied depending on the feeding substrate provided. University canteen leftovers resulted in the BSFL having at least 18% greater length (17.00 mm) and 56% greater weight (3.15 g) compared to other treatments. The highest amounts of protein (38.9%) and oil (39.06%) were observed in the UCL treatment, while the BV treatment larvae had the highest quantities of ash (28.9%) and dry matter (28.0%). The fatty acid profile of the BSFL revealed three-times-higher levels of saturated fatty acids than unsaturated fatty acids in the UCL treatment and was at least twice as high in other treatments. Overall, the BSFL had the best growth on the UCL substrate, and the combination of bagasse and vinasse (BV) was the most appropriate substrate for BSFL development among the sugarcane by-products.

12548 Mammary De Novo Lipogenesis During A Hyperinsulinemic-euglycemic Clamp

Abstract Disclosure: T.M. Fordham: None. M. Ramos-Roman: None. E.J. Parks: Consulting Fee; Self; Simply Good Foods. Stock Owner; Self; Sagimet Biosciences. Other; Self; Past President of The Obesity Society. Introduction: The mammary produces large amounts of medium-chain saturated fatty acids. Long-chain saturated fatty acids found in human milk primarily derive from the maternal diet or from the mobilization of stored triglycerides. Previous studies have established the importance of insulin in stimulating mammary differentiation, milk synthesis, and lipogenesis. However, no studies have assessed how changes in insulin concentrations alter human mammary de novo lipogenesis (DNL) nor what effect gestational diabetes may have on insulin’s relationship to lipogenesis during lactation. Through the utilization of stable isotopes and the hyperinsulinemic-euglycemic clamp technique, we tested the differing concentrations of insulin to stimulate mammary DNL. Methods: Eight women (32±4 yrs) with (GDM, n=4) or without (NGT, n=4) recent gestational diabetes and overweight or obesity (28.2±2.9 kg/m2) were recruited to participate in this study at 6 weeks postpartum. The night before the study, participants orally consumed 3 doses of 70% deuterated water to label newly made fatty acids. Participants arrived in the morning for IV placement and immediately pumped milk contralaterally for 20 minutes. Milk was pumped two hours later, again at the end of step 1 of the clamp (10 mU/m2/min) and once more after step 2 (either 20 or 40 mU/m2/min). Milk triglycerides were extracted and prepared for analysis by gas chromatography-mass spectrometry. The incorporation of deuterium into milk triglyceride-fatty acids was the primary outcome. Results: Fasting insulin concentrations were significantly associated with newly-made 16:0 in milk triglycerides (r=0.85, P=0.01). Of all measured triglyceride 16:0, 1.6±1.0% were made de novo. This percentage increased 1.5-fold by the end of step 2 of the clamp (P=0.06). Fasting milk DNL 14:0 was 12.3±4.8% which was significantly greater than DNL 16:0 (P&amp;lt;0.01). DNL 14:0 increased 1.7-fold during step 2 (P=0.04). For both milk triglyceride 12:0 and 14:0 derived from DNL, a significant effect across clamp-stage was observed (P&amp;lt;0.001 for both), but not an effect of group (P=0.12, P=0.11, respectively). Bonferroni posthoc analyses revealed that the insulin effect was significant for both groups for 12:0 (GDM, P=0.02; NGT, P &amp;lt;0.01) and 14:0 (GDM, P&amp;lt;0.01; NGT, P=0.01). Interpretation: The present study is the first to assess the acute effect of a hyperinsulinemic-euglycemic clamp on the synthesis of newly-made triglyceride fatty acids in human milk. These results suggest that the increases in mammary DNL may be fatty acid specific, favoring that of lauric and myristic acids, but not longer chain fatty acids like palmitate. Mammary lipogenesis was stimulated by insulin in all subjects regardless of recent gestational diabetes diagnosis. The role mammary DNL plays in overall milk fat content deserves further investigation. Presentation: 6/3/2024

12548 Mammary De Novo Lipogenesis During A Hyperinsulinemic-euglycemic Clamp

Abstract Disclosure: T.M. Fordham: None. M. Ramos-Roman: None. E.J. Parks: Consulting Fee; Self; Simply Good Foods. Stock Owner; Self; Sagimet Biosciences. Other; Self; Past President of The Obesity Society. Introduction: The mammary produces large amounts of medium-chain saturated fatty acids. Long-chain saturated fatty acids found in human milk primarily derive from the maternal diet or from the mobilization of stored triglycerides. Previous studies have established the importance of insulin in stimulating mammary differentiation, milk synthesis, and lipogenesis. However, no studies have assessed how changes in insulin concentrations alter human mammary de novo lipogenesis (DNL) nor what effect gestational diabetes may have on insulin’s relationship to lipogenesis during lactation. Through the utilization of stable isotopes and the hyperinsulinemic-euglycemic clamp technique, we tested the differing concentrations of insulin to stimulate mammary DNL. Methods: Eight women (32±4 yrs) with (GDM, n=4) or without (NGT, n=4) recent gestational diabetes and overweight or obesity (28.2±2.9 kg/m2) were recruited to participate in this study at 6 weeks postpartum. The night before the study, participants orally consumed 3 doses of 70% deuterated water to label newly made fatty acids. Participants arrived in the morning for IV placement and immediately pumped milk contralaterally for 20 minutes. Milk was pumped two hours later, again at the end of step 1 of the clamp (10 mU/m2/min) and once more after step 2 (either 20 or 40 mU/m2/min). Milk triglycerides were extracted and prepared for analysis by gas chromatography-mass spectrometry. The incorporation of deuterium into milk triglyceride-fatty acids was the primary outcome. Results: Fasting insulin concentrations were significantly associated with newly-made 16:0 in milk triglycerides (r=0.85, P=0.01). Of all measured triglyceride 16:0, 1.6±1.0% were made de novo. This percentage increased 1.5-fold by the end of step 2 of the clamp (P=0.06). Fasting milk DNL 14:0 was 12.3±4.8% which was significantly greater than DNL 16:0 (P&amp;lt;0.01). DNL 14:0 increased 1.7-fold during step 2 (P=0.04). For both milk triglyceride 12:0 and 14:0 derived from DNL, a significant effect across clamp-stage was observed (P&amp;lt;0.001 for both), but not an effect of group (P=0.12, P=0.11, respectively). Bonferroni posthoc analyses revealed that the insulin effect was significant for both groups for 12:0 (GDM, P=0.02; NGT, P &amp;lt;0.01) and 14:0 (GDM, P&amp;lt;0.01; NGT, P=0.01). Interpretation: The present study is the first to assess the acute effect of a hyperinsulinemic-euglycemic clamp on the synthesis of newly-made triglyceride fatty acids in human milk. These results suggest that the increases in mammary DNL may be fatty acid specific, favoring that of lauric and myristic acids, but not longer chain fatty acids like palmitate. Mammary lipogenesis was stimulated by insulin in all subjects regardless of recent gestational diabetes diagnosis. The role mammary DNL plays in overall milk fat content deserves further investigation. Presentation: 6/3/2024

Differential Fatty Acid Response of Resident Macrophages in Human Skeletal Muscle Fiber and Intermuscular Adipose Tissue.

Human skeletal muscle contains different types of tissues with skeletal muscle fibers (SMFs) and intermuscular adipose tissues (IMATs) as the main components. We maintained human skeletal muscle tissues from 12 study participants under native conditions in vitro for 11 days to investigate the dynamics of macrophages that reside in adjacent IMATs and SMFs simultaneously. The samples were subjected to immunohistochemical analysis for macrophage phenotyping and mitochondrial mass assessment before and after maintenance in vitro. Multiplex protein analysis was used to determine cytokine/chemokine expression in tissue extracts. The results revealed significant correlations between donor age or body mass index (BMI) and distinct phenotypes of resident macrophages in SMFs and IMATs. The dynamics of SMF- and IMAT-resident macrophages differed significantly in vitro and exhibited inverse correlations with chemokine/cytokine expression levels and mitochondrial activity. Moreover, the responses of macrophages to saturated and unsaturated fatty acids (FAs) differed substantially between SMFs and IMATs. These findings showed the functional diversity of phenotypically identical macrophages in adjacent niches. Thus, the currently available macrophage markers cannot capture the functional diversity of human tissue-resident macrophages. The model used in the present study may help elucidate how macrophages affect muscle homeostasis and disease in humans.

Associations of the rs12504538 and rs6824447 Polymorphisms of the Elovl6 Gene with Estimated Elongase and Desaturase Activity and Fatty Acid Concentrations in Mexican Women with Gestational Diabetes Mellitus

Background: This study aimed to investigate the possible associations of the rs12504538 and rs6824447 polymorphisms of the Elovl6 gene with estimated elongase and desaturase activity and saturated fatty acid concentrations in Mexican women with Gestational Diabetes Mellitus (GDM). Methods: We recruited 172 women in the second and third trimesters of pregnancy who had undergone an oral glucose tolerance test, including 66 who had diagnosed with GDM according to the 2016 ADA criteria and 106 who had normal glucose tolerance test results, from the General Hospital and Health Centers of the Health Ministry of Guanajuato, México. Participants were matched by gestational week. Data on age, gestational week and anthropometric characteristics were collected. Blood samples were drawn after an overnight fast for the measurement of serum glucose, lipid, NEFA, serum fatty acid and insulin levels; SNP genotyping and quantification of fatty acids was performed and elongase and desaturase activity was estimated. Findings: With the exception of HDL-cholesterol, all variables, including NEFA levels, were significantly greater in the GDM group than in the non-GDM group. The rs6824447 polymorphism of the Elovl6 gene, an age &gt;25 years and HOMA-IR levels were associated with the development of GDM (OR=5.1, 95% CI 1.56-17.1, p=0.006; OR=4.89, 95% CI 1.65-14.4, p=0.003; OR=34.1 95% CI 8.7-133, p&lt;0.000001, respectively). Palmitic acid (OR=1.08; 95% CI: 1.06-1.11; p&lt;0.001) and oleic acid (OR=1.17; 95% CI: 1.14-1.2; p&lt;0.001) concentrations were also associated with the development of GDM. No differences in the estimated elongase and desaturase activity among the non-GDM and GDM groups were found and only the activity of Δ9D SCD18 desaturase was marginally high in GDM patients (p=0.050). Conclusion: The rs6824447Elovl6 polymorphism is associated with the development of GDM, as are high serum palmitic acid, oleic acid and stearic acid concentrations and estimated Δ9D SCD18 desaturase activity.

Sphingomyelin-enriched milk phospholipids offer superior benefits in improving the physicochemical properties, microstructure, and surface characteristics of infant formula

Phospholipids from different sources have varying chemical compositions, but how they contribute to different properties of infant formula is unclear. In this study, four types of phospholipids, milk phospholipids (MPLs), soybean phospholipids (SBPLs), sunflower phospholipids (SFPLs), and egg yolk phospholipids (EYPLs), were added to infant formula to investigate their physicochemical properties, microstructure, and surface characteristics. MPLs uniquely offer high sphingomyelin and saturated fatty acid levels. The MPL-based emulsion had the smallest particle size (334.50 nm), lowest stability constant (0.30), and highest viscosity among all groups tested. Furthermore, the abundance of sphingomyelin in MPLs allowed for a denser interfacial film and the complete phospholipid-coated structure of lipid droplets in infant formula emulsion. This consequently improved the microstructure and fat encapsulation of the powder, leading to significantly lower surface fat content in the MPL group. Therefore, the proper selection of phospholipids is crucial for modulating the stability and surface characteristics of infant formula.