Trans-unsaturated Fatty Acids Research Articles

Awareness, knowledge, and behaviors regarding trans unsaturated fatty acids in a sample of Lebanese adults

AbstractLebanon is a country in the Middle East that had been witnessing nutrition transition to a westernized diet high in trans fats (TFs) and saturated fatty acids (TFAs) that had been linked to cardiovascular diseases and many other health issues. This study examines TF‐related awareness, knowledge, and self‐reported behaviors among a sample of Lebanese adults aged between 18 and 64 years, as well as their association with sociodemographic factors and anthropometric measurements. Using a multicomponent questionnaire, a cross‐sectional study was conducted online, across all Lebanese regions based on a convenience sampling method (n = 401). Factors associated with TF‐related awareness, knowledge, and behaviors were examined by multivariate linear regression analysis. The study highlighted specific gaps in TF‐related awareness, knowledge, and behavioral practices as well as differences by sociodemographic factors. Most of the participants (36%) had heard of partly hydrogenated oils (PHOs) rather than TFs (49%). A higher proportion of respondents (54%) said they understood a little about TFs, the majority had inadequate knowledge about the foods that contain TFs, and 44% said they would not give up eating their favorite snack even if they knew it contains TFs. Overall, consumers' awareness and knowledge about TFs are rather low and the majority had fair behavioral practices. In addition, being a woman and having higher education level were significantly associated with higher levels of TFs awareness, knowledge, and behavior scores. Higher behavior scores were shown in older participants, married, and those who had part‐time jobs, whereas having higher income and normal weight were significantly associated with higher awareness scores. These findings offer valuable insight into TF‐related awareness, knowledge, and behaviors in a sample of Lebanese adults and provide key information that could spur the development of evidence‐based TFs reduction interventions specific to the Middle East.

Nutritional, Utility, and Sensory Quality and Safety of Sunflower Oil on the Central European Market

In the quality monitoring of 18 sunflower oil samples from the EU market, 14 were refined and 4 were cold-pressed. They demonstrated high quality of technological processing with low values of trans-unsaturated fatty acids, acid value, and peroxide value and also met the limits set by legislation in the content of process contaminants 3-monochloropropane-1,2-diol (3-MCPD) esters and glycidyl esters. Measurements of oxidative stability showed a difference in utility value. The average induction period of the oils from the traditional varieties was 2.6 h, predisposing them to cold cooking or short-term frying, while the 11.8 h of the four high oleic sunflower oils (HOSO) indicates the possibility of long-term heat stress. The nutritional benefit is the average vitamin E content of 663 mg/kg oil. The overall sensory quality of the samples was evaluated by a 12-member panel of trained assessors. On the seven-point category scale, the oils were of good to exceptional quality. The cold-pressed oils (CPOs) differed in having, on average, lower trans-unsaturated fatty acid content, process contaminants at unmeasurable levels, and, on average, higher vitamin E concentrations. The specific organoleptic properties of the CPOs were characterized by a pleasant nutty and sunflower seed flavor.

Is Diet A Contributing Factor To Infertility?

Objective: To evaluate the effect of dietary trans-unsaturated fatty acids (TFAs) on ovulatory infertility in young unmarried females.Methods: This cross-sectional study was conducted from 1 august 2023 to 31 December 2023 at the Basic Medical Science Institute (BMSI), Jinnah Postgraduate Medical Center Karachi. All healthy unmarried females aged 15-25 were included in the study. Females with a family history of infertility, having existing comorbidity, history of irregular menstruation cycle or hormonal replacement therapy, were excluded. Based on the Food frequency questionnaire score, 300 subjects were divided into 3 groups, Group A were low trans fats Consumers (Score 0-170), Group B was moderate trans fats consumers(Score 171-340) and Group C were high trans fats consumers (Score 341-500). The analysis of results was carried out on SPSS Software version 22.Results: The study’s 300 respondents, who ranged in age from 16 to 25, had a mean age of 21.8 years. Fifteen per cent of those in group “A” had abnormal HDL, 22% had bad LDL, and 23% had abnormal TGA, while 17% had abnormal cholesterol. An abnormal TGA, abnormal HDL, abnormal LDL, and abnormal 31% of the participants in group “B” exhibited abnormal cholesterol levels. A significant correlation between oxidative stress and hormonal indicators was found in three groups: “A” (13%) had aberrant LH, “20%” had abnormal FSH, “11%” had abnormal serum estrogen, “10%” had abnormal serum progesterone, and “C” (49% had abnormal LH, FSH, estrogen, and progesterone). Food frequency questionnaire (FFQ ) scores had a 25% positive correlation with cholesterol, a 40% negative correlation with HDL, a 31% positive correlation with LDL, and a 39% positive correlation with biochemical and hormonal indicators.Conclusion: Trans fats diets significantly increase the risk of ovulatory infertility and reproductive failure in young females

Lifestyle and Lipoprotein(a) Levels: Does a Specific Counseling Make Sense?

Lipoprotein(Lp)(a) is a variant of low-density lipoprotein (LDL), bound to apolipoprotein B100, whose levels are associated with a significant increase in the risk of atherosclerosis-related cardiovascular events, but also to aortic stenosis and atrial fibrillation. Since plasma levels of Lp(a) are commonly considered resistant to lifestyle changes, we critically reviewed the available evidence on the effect of weight loss, dietary supplements, and physical activity on this risk factor. In our review, we observed that relevant body weight loss, a relatively high intake of saturated fatty acids, the consumption of red wine, and intense physical exercise seems to be associated with significantly lower plasma Lp(a) levels. On the contrary, foods rich in trans-unsaturated fatty acids are associated with increased Lp(a) levels. With regard to dietary supplements, coenzyme Q10, L-Carnitine, and flaxseed exert a mild but significant lowering effect on plasma Lp(a).

Improvement of environmental tolerance of E. coli through biological membrane engineering to boost succinic acid conversion

Escherichia coli has been applied as an important platform for carboxylic acids production, such as succinic acid (SA). However, carboxylic acids will cause membrane damage, inhibiting E. coli growth and metabolism, which has been considered as one of the main obstacles to large-scale SA production. In this study, the approach of biological membrane engineering was attempted to improve the environmental tolerance of E. coli, which resulted from the change of membrane lipid composition. After introduction of whiB with function of stress responses and cell division, and cti with capability of trans unsaturated fatty acids biosynthesis, the SA production in the 5-L fermenter reached 80.0 g/L, which was 37.0% higher than that of the control group. Further incorporating fabA and fabB to promote unsaturated fatty acid biosynthesis of membrane, the engineered E. coli showed higher survival rate and better metabolic performance under the harsh environments, including exogenous octanoic acid (C8) addition, high osmotic pressure and low pH. The change of membrane composition contributed to the stronger resistance of E. coli, in particular the SA production still reached 29.9 g/L with 0.79 g/g of yield under low pH (pH 5.6) in the 5-L fermenter. The membrane engineering strategy is proved to be effective in improving strain robustness, paving the way to boost the large-scale production of carboxylic acids.

The Role of Dietary Fats in the Development and Treatment of Endometriosis.

Endometriosis is an estrogen-dependent disease in women of childbearing age that affects approximately 5-15% of the female population. The etiology of endometriosis is complex, multifaceted, and not fully understood. In endometriosis, which is an estrogen-related chronic inflammatory condition, estrogen plays a major role in endometrial cellular growth. High estrogen levels could be another risk factor for developing endometriosis. The aim of this review is to update knowledge on the impact of dietary fats on the development of endometriosis and chronic inflammation in women with endometriosis and diet therapy. Dietary fat may be linked with the progression and development of endometriosis, but studies have been contradictory due to various issues including sample size, different study designs, and different methodological aspects. Results have shown that the risk of endometriosis may increase with a higher consumption of products rich in saturated fats, especially palmitic acid and trans-unsaturated fatty acids. Monounsaturated fats and omega-3 polyunsaturated fatty acids may likely be connected with a lower risk of developing endometriosis and with reductions in the severity of disease. Monounsaturated fats, omega-3 polyunsaturated fatty acids, and a suitable eicosapentaenoic acid to arachidonic acid ratio can be used in diet therapy to improve quality of life by reducing pain and inflammation. Further research is needed in order to fully understand the influence of dietary fats on the risk of development of this disease.

Features of nutrition in women with arterial hypertension and abdominal obesity

Abstract Funding Acknowledgements Type of funding sources: None. Aim The study was aimed to investigate the nutritional characteristics of female patients (residents of Ukraine) with arterial hypertension and abdominal obesity. Materials and methods We examined 75 female patients (residents of Ukraine) with AH stage II, 2–3 degrees, aged from 40 to 59 years (40 women with AO (I–II degrees) and 35 women with normal body weight (NBW). All patients underwent a routine examination. The peculiarities of the nutrition of the patients were analyzed using the questionnaire "Diary of daily nutrition". Results The energy value of the daily ration was higher in the group of women with AH and AO (2782.4 [2214.6; 3118.4] kcal), than in women with AH and NBW (1823.2 [1516.5; 2368.5] kcal, р < 0,05. In the group of women with AH and AO, the maximum energy value of the daily ration was for dinner in the most of the examined (73%), in women with AH and NBW - only in 43% (p <0.05). The study of the macronutrient composition of the daily diet of patients showed a significant increase in fat intake (106.8 [87.9; 182.0] g / day) in the main group, in contrast to the comparison group (50.5 [38.5; 118.7] g/ day), p <0.01. Intake of saturated fatty acids (p <0.01) and trans-unsaturated fatty acids (p <0.01) was also likely to be higher in the group of women with АН and AO than in the group of women with AH and NBW. Women with AH and AO probably consumed more carbohydrates than women with AH and NBW (375.1 [302.4; 447.3] g / day and 269.2 [211.7; 374.8] g / day respectively, p <0.05. Daily protein intake in the group of women with AH in combination with AO and in the group of women with AH and NBW probably did not differ and amounted to 81.2 [57.4; 127.6] g / day and 74.5 [56.6; 132.7] g / day (p <0.05). Women with AH and AO consumed an insufficient amount of dietary fiber - 28.8 [6.3; 38.4] g/day. At the same time, the consumption of dietary fiber in the group of women with AH and NBW was probably high - 39.2 [15.9; 52.5] g / day (p <0.05) and corresponded to the European norms of healthy nutrition. The groups of women probably did not differ in the level of consumption of table salt (p = 0.082) and in the number of persons who "add salt to their food". Conclusions Significant violations of the healthy eating norms were found in women with AH, which were much more pronounced in women with AO that must be taken into account when developing optimal schemes for correcting the diet in these patients.

A convenient route to mono-trans polyunsaturated free fatty acids

Trans unsaturated fatty acids in humans may be originated both from dietary supplementation and from an endogenous free-radical-catalyzed cis−trans isomerization of fatty acid residues in naturally occurring cis lipids. The latter process affords geometrical isomers and the polyunsaturated fatty acid mono-trans isomers were demonstrated to be connected with stress conditions in living organisms. Synthesis of mono-trans polyunsaturated fatty acid is useful for analytical and biological research, and in this case, the availability of free fatty acids is needed as well as the possibility of mg scale of the synthetic protocol. Herein, we report a simple synthetic route to mono-trans isomers of arachidonic acid, eicosapentaenoic acid, and docosahexaenoic acid, which includes thiyl radical-catalyzed isomerization reaction of polyunsaturated fatty acid methyl esters and fraction isolation of mono-trans mixture isomers followed by optimization of hydrolysis condition to free fatty acids and purification of each mono-trans polyunsaturated fatty acid. Our approach to mono-trans polyunsaturated fatty acids as free acids can reach the mg scale, thus fostering more applications to biochemical and biological studies.

Features of nutrition in women with arterial hypertension and abdominal obesity

Background. Currently, there is a significant increase in the percentage of women with arterial hypertension (AH) and abdominal obesity (AO), which is largely due to violations of the healthy eating norms. Therefore, the problem of studying the nutritional characteristics of women with AH in combination with AO requires further research. The study was aimed to investigate the nutritional characteristics of female patients (residents of Ukraine) with arterial hypertension and abdominal obesity. Materials and methods. We examined 75 female patients (residents of Ukraine) with AH stage II, 2–3 degrees, aged from 40 to 59 years (40 women with AO (I–II degrees) and 35 women with normal body weight (NBW). All patients underwent a routine examination. The peculiarities of the nutrition of the patients were analyzed using the questionnaire “Diary of daily nutrition”. The data obtained were analyzed using the SPSS 19 computer program for Windows XP. Results. In the group of women with AH and AO, in the vast majority of individuals (73–100 %), the diet did not meet the recommendations of a healthy diet. In the group of women with AH and NBW, the dietary pattern did not meet the recommendations of a healthy diet only in one-third of the individuals. The daily diet of women with AH and AO differed from that of women with AH and NBW by a significantly higher energy value of food, a higher frequency of meals in the evening, a higher intake of fats (including saturated fatty acids and trans-unsaturated fatty acids), carbohydrates (especially monosaccharides), and less dietary fiber intake. In both groups of women, the habit of adding salt to food was revealed, but only in the third of the individuals. Conclusions. Significant violations of the healthy eating norms were found in women with AH, which were much more pronounced in women with AO that must be taken into account when developing optimal schemes for correcting the diet in these patients.

Road to trans-fat free Philippines: An emerging milestone amidst COVID-19 pandemic

Road to trans-fat free Philippines: An emerging milestone amidst COVID-19 pandemic

250 Evaluation of Green Grass as a feed ingredient in beef finishing rations and impact on cattle performance, carcass characteristics, and fatty acid profiles in meat

Abstract A finishing study used 240 crossbred steers (initial BW=340 ±24 kg) to evaluate performance, carcass characteristics, and fatty acid profiles of beef from finishing steers. Four inclusions (0, 10, 20, 30 % DM basis) of Green Grass displaced dry rolled corn in the finishing diet. Green Grass is a blend of herbs and plants imported from Korea that are high in omega-3 fatty acids with 13.9 % fat,32.0 % CP, and 27.0 % Acid detergent fiber. The remaining diet consisted of 15 % WDGS, 20 % corn silage, and 6 % liquid supplement (DM basis). There were no differences in final BW, gain or carcass traits (P³0.14). Cattle were harvested over three slaughter days and were fed for 190, 199, or 203 days. Dry matter intake linearly increased (P = 0.04)as Green Grass inclusion increased in the diet. A linear response (P£0.01) to feeding Green Grass was observed for G:F, with steers fed Green Grass having lower feed efficiency than control cattle. The G:F of cattle fed Green Grass was 5.4, 3.4, and 6.8 % lower in G:F as inclusion increased suggesting Green Grass has 68.6 % the energy of corn it replaced. Steers fed 30 % Green Grass had a lower marbling score. Linear increases in alpha linolenic acid, trans-unsaturated fatty acids, and omega-3 fatty acids (P£0.01) were observed in steak samples from steers fed increasing inclusion of Green Grass. Including up to 30 % inclusion of Green Grass on a DM basis in finishing diets decreased G:F; however, it appeared to have no other effects on performance or carcass characteristics. Feeding Green Grass linearly improved omega-3 fatty acid concentration in beef.

Nonesterified Fatty Acids and Depression in Cancer Patients and Caregivers.

ABSTRACTBackgroundNonesterified fatty acids (NEFAs) are known to have inflammatory effects. The inflammatory hypothesis of depression suggests that omega-3 (ω-3) and omega-6 (ω-6) fatty acids might be negatively and positively correlated with depression, respectively.ObjectiveAn exploratory study was conducted to determine the association between dietary free fatty acids and depressive symptoms in cancer patients and caregivers.MethodsAssociations between depression and the NEFA pool were investigated in 56 cancer patients and 23 caregivers using a combination of nonparametric tests and regularized regression. Plasma NEFAs were measured using thin layer and gas chromatography with flame ionization detection. Depression was characterized both as a continuous severity score using the GRID-Hamilton Depression Rating Scale (GRID Ham-D), and as a categorical diagnosis of major depression by structured clinical interview.ResultsInitial hypotheses regarding the relation between depression and omega-3 or omega-6 fatty acids were not well supported. However, elaidic acid, a trans-unsaturated fatty acid found in hydrogenated vegetable oils, was found to be negatively correlated with continuous depression scores in cancer patients. No significant associations were found in caregivers.ConclusionsAn unexpected negative association between elaidic acid and depression was identified, supporting recent literature on the role of G protein–coupled receptors in depression. Further research is needed to confirm this result and to evaluate the potential role of G protein agonists as therapeutic agents for depression in cancer patients.

6.B. Workshop: Partnerships with the private sector to tackle NCDs - do healthy profits trump healthy people?

Abstract The determinants of health and well-being are partly driven by the interests - narrowly financial? - of big corporate players. Tackling the root causes of threats to health and well-being is often at odds with the business interests of economic operators and lobbies, and even in the era of Sustainable Development Goals, it is not yet clear for most citizens how companies hold themselves to account on non-financial impacts. Their explicit role, level of funding and tactics are therefore not yet always open to the high level of transparency that may be required to involve these “giants” trustfully in the health policy process. At the same time, as health policy seeks to shape market conditions, we actively want economic operators to be stakeholders ever more directly affected by public policy. Data from the Global Burden of Disease Study shows an overwhelming strain in the EU as a result of non-communicable diseases (NCDs), with estimates that they cause over 91% of deaths and almost 87% of Disability-Adjusted Life-Years. Risk factors for NCDs are associated with the production, marketing and consumption of commercially produced food and beverages, particularly those containing sugar, salt, trans unsaturated fatty acids, alcohol and tobacco. But the food and drink industry is also the EU's biggest manufacturing sector, and in half of Member States represents the biggest employer in manufacturing. The power of markets and business in health - the 'commercial determinants' of health - are undeniable in this context, and the political difficulty of regulating such behemoth market players is all too clear. Policy decision-makers face a complex challenge in trying to effectively address the root causes of NCDs, while navigating strong transnational interests, lobbies and marketing impacts of industry stakeholders. The objective of this workshop is to discuss issues around the right framing for any partnership working with industry to tackle NCDs. Under what conditions might all stakeholders usefully sit at the table across divides in interests and values, and are there lines to be drawn as to who we are willing to partner with, when, how and on which policy issues? What are the risks, and how might It be it possible to balance these? Do we need new ways of partnership working? Can we find co-benefits and learn from innovative models? Or are the profit-driven motives of the commercial sector sometimes simply incompatible with health interests? Format-wise, two speakers will first present different perspectives on engaging with the private sector on NCDs - one supportive and the other more cautionary. The second segment of the workshop will comprise a panel discussion, incorporating the contributions of online attendees concerning their experiences of working on this topic and questions for panelists submitted through the webinar too's Q&A chat function. Key messages Corporate strategies and products strongly influence consumption patterns and impact health worldwide. Health actors must be risk-aware of partnership work with the private sector, while harnessing opportunities to engage with socially innovative business models to maximise positive health impacts.

Structural Lesions of Proteins Connected to Lipid Membrane Damages Caused by Radical Stress: Assessment by Biomimetic Systems and Raman Spectroscopy.

Model systems constituted by proteins and unsaturated lipid vesicles were used to gain more insight into the effects of the propagation of an initial radical damage on protein to the lipid compartment. The latter is based on liposome technology and allows measuring the trans unsaturated fatty acid content as a result of free radical stress on proteins. Two kinds of sulfur-containing proteins were chosen to connect their chemical reactivity with membrane lipid transformation, serum albumins and metallothioneins. Biomimetic systems based on radiation chemistry were used to mimic the protein exposure to different kinds of free radical stress and Raman spectroscopy to shed light on protein structural changes caused by the free radical attack. Among the amino acid residues, Cys is one of the most sensitive residues towards the attack of free radicals, thus suggesting that metal-Cys clusters are good interceptors of reactive species in metallothioneins, together with disulfides moieties in serum albumins. Met is another important site of the attack, in particular under reductive conditions. Tyr and Phe are sensitive to radical stress too, leading to electron transfer reactions or radical-induced modifications of their structures. Finally, modifications in protein folding take place depending on reactive species attacking the protein.

A novel synthesis of trans-unsaturated fatty acids by the Gram-positive commensal bacterium Enterococcus faecalis FA2-2.

A key mechanism of Pseudomonas spp. adaptation to environmental stressors is their ability to convert the cis-unsaturated fatty acids of the membrane lipids to their trans-isomers to rigidify the membrane and thereby resist stresses. Although this Cti-catalyzed enzymatic isomerization has been well investigated in the P. putida paradigm, several bacterial species have been found to produce trans-unsaturated fatty acids. Although cti orthologs have only been reported in Gram-negative bacteria, we report that E. faecalis FA2-2 cultures synthesize trans-unsaturated fatty acids during growth by a mechanism similar of P. putida. Although the role of trans-unsaturated fatty acids (trans-UFAs) in E. faecalis remains obscure, our results indicate that organic solvents, as well as the membrane altering antibiotic, daptomycin, had no effect on trans-UFA formation in E. faecalis FA2-2. Moreover trans-UFA production in E. faecalis FA2-2 membranes was constant in oxidative stress conditions or when metal chelator EDTA was added, raising the question about the role of heme domain in cis-trans isomerization in E. faecalis FA2-2. Although growth temperature and growth phase had significant effects on cis-trans isomerization, the bulk physical properties of the membranes seems unlikely to be altered by the low levels of trans-UFA. Hence, any effects seems likely to be on membrane proteins and membrane enzyme activities. We also report investigations of cti gene distribution in bacteria was and suggest the distribution to be triggered by habitat population associations. Three major Cti clusters were defined, corresponding to Pseudomonas, Pseudoalteromonas and Vibrio Cti proteins.

Diets Enriched with Conventional or High-Oleic Acid Canola Oils Lower Atherogenic Lipids and Lipoproteins Compared to a Diet with a Western Fatty Acid Profile in Adults with Central Adiposity

Novel oils high in monounsaturated fatty acids (MUFAs) and low in saturated fatty acids (SFAs) are an alternative to partially hydrogenated oils high in trans-unsaturated fatty acids. There is widespread use of high-MUFA oils across the food industry; however, limited knowledge of their cardiovascular impact exists. We investigated the effects of diets containing canola oil, high-oleic acid canola oil (HOCO), and a control oil blend (diet formulated to emulate a Western fat profile) on lipids, lipoproteins, and apolipoproteins (apos), as secondary outcomes of the trial. In a multi-center, double-blind, randomized, 3-period crossover, controlled feeding trial, men (n=44) and women (n=75) with a mean age of 44 y, mean body mass index (BMI; in kg/m2) of 31.7, and an increased waist circumference plus≥1 metabolic syndrome criteria consumed prepared, weight-maintenance diets containing canola oil [17.5% MUFAs, 9.2% polyunsaturated fatty acids (PUFAs), 6.6% SFAs], HOCO (19.1% MUFAs, 7.0% PUFAs, 6.4% SFAs), or control oil (10.5% MUFAs, 10.0% PUFAs, 12.3% SFAs) for 6 wk with ≥4-wk washouts. Fasting serum lipids were assessed at baseline and 6 wk. Diet effects were examined using a repeated measures mixed model. Compared with the control, canola and HOCO diets resulted in lower endpoint total cholesterol (TC; -4.2% and -3.4%; P<0.0001), LDL cholesterol (-6.6% and -5.6%; P<0.0001), apoB (-3.7% and -3.4%; P=0.002), and non-HDL cholesterol (-4.5% and -4.0%; P=0.001), with no differences between canola diets. The TC:HDL cholesterol and apoB:apoA1 ratios were lower after the HOCO diet than after the control diet (-3.7% and -3.4%, respectively). There were no diet effects on triglyceride, HDL cholesterol, or apoA1 concentrations. HOCO, with increased MUFAs at the expense of decreased PUFAs, elicited beneficial effects on lipids and lipoproteins comparable to conventional canola oil and consistent with reduced cardiovascular disease risk in adults with central adiposity. This trial was registered at www.clinicaltrials.gov as NCT02029833.

Membrane engineering via trans-unsaturated fatty acids production improves succinic acid production in Mannheimia succiniciproducens.

Engineering of microorganisms to produce desired bio-products with high titer, yield, and productivity is often limited by product toxicity. This is also true for succinic acid (SA), a four carbon dicarboxylic acid of industrial importance. Acid products often cause product toxicity to cells through several different factors, membrane damage being one of the primary factors. In this study, cis-trans isomerase from Pseudomonas aeruginosa was expressed in Mannheimia succiniciproducens to produce trans-unsaturated fatty acid (TUFA) and to reinforce the cell membrane of M. succiniciproducens. The engineered strain showed significant decrease in membrane fluidity as production of TUFAenabled tight packing of fatty acids, which made cells to possess more rigid cell membrane. As a result, the membrane-engineered M. succiniciproducens strain showed higher tolerance toward SA and increased production of SA compared with the control strain without membrane engineering. The membrane engineering approach employed in this study will be useful for increasing tolerance to, and consequently enhancing production of acid products.

Trans-Fats Inhibit Autophagy Induced by Saturated Fatty Acids

Depending on the length of their carbon backbone and their saturation status, natural fatty acids have rather distinct biological effects. Thus, longevity of model organisms is increased by extra supply of the most abundant natural cis-unsaturated fatty acid, oleic acid, but not by that of the most abundant saturated fatty acid, palmitic acid. Here, we systematically compared the capacity of different saturated, cis-unsaturated and alien (industrial or ruminant) trans-unsaturated fatty acids to provoke cellular stress in vitro, on cultured human cells expressing a battery of distinct biosensors that detect signs of autophagy, Golgi stress and the unfolded protein response. In contrast to cis-unsaturated fatty acids, trans-unsaturated fatty acids failed to stimulate signs of autophagy including the formation of GFP-LC3B-positive puncta, production of phosphatidylinositol-3-phosphate, and activation of the transcription factor TFEB. When combined effects were assessed, several trans-unsaturated fatty acids including elaidic acid (the trans-isomer of oleate), linoelaidic acid, trans-vaccenic acid and palmitelaidic acid, were highly efficient in suppressing autophagy and endoplasmic reticulum stress induced by palmitic, but not by oleic acid. Elaidic acid also inhibited autophagy induction by palmitic acid in vivo, in mouse livers and hearts. We conclude that the well-established, though mechanistically enigmatic toxicity of trans-unsaturated fatty acids may reside in their capacity to abolish cytoprotective stress responses induced by saturated fatty acids.

Authentication and Nutritional Benefits of Cheeses Based on Vegetable Oils

The fatty acid profile of a number of commercial fermented cheeses, based on vegetable oils or milk lipids have been evaluated by GC-FID (gas chromatography with flame ionization detector), disclosing the quantity of SFAs (saturated fatty acids), MUFAs (monounsaturated fatty acids) and PUFAs (polyunsaturated fatty acids), as well as the presence of small quantities of TUFAs (trans unsaturated fatty acids) in the dairy products. The authentication of the cheeses based on vegetable oil or milk was performed by GC or IR fingerprinting.

Rumen microbiota and dietary fat: a mutual shaping.

Although fat content in usual ruminant diets is very low, fat supplements can be given to farm ruminants to modulate rumen activity or the fatty acid (FA) profile of meat and milk. Unsaturated FAs, which are dominant in common fat sources for ruminants, have negative effects on microbial growth, especially protozoa and fibrolytic bacteria. In turn, the rumen microbiota detoxifies unsaturated FAs (UFAs) through a biohydrogenation (BH) process, transforming dietary UFAs with cis geometrical double-bonds into mainly trans UFAs and, finally, into saturated FAs. Culture studies have provided a large amount of data regarding bacterial species and strains that are affected by UFAs or involved in lipolysis or BH, with a major focus on the Butyrivibrio genus. More recent data using molecular approaches to rumen microbiota extend and challenge these data, but further research will be necessary to improve our understanding of fat and rumen microbiota interactions.