Types Of Polyunsaturated Fatty Acids Research Articles

Relationship between Polyunsaturated Fatty Acid Metabolism and Atherosclerosis.

Multiple factors cause atherosclerosis, meaning its pathogenesis is complex, and has not been fully elucidated. Polyunsaturated fatty acids are a member of the fatty acid family, which are critical nutrients for mammalian growth and development. The types of polyunsaturated fatty acids ingested, their serum levels, and fatty acid desaturase can influence the atherosclerotic disease progression. The fatty acid desaturase gene cluster can regulate fatty acid desaturase activity and further affect atherosclerosis. This study reviewed the research progress on the effects of polyunsaturated fatty acids on atherosclerosis regulated by fatty acid desaturase and the relationship between genetic variants of the fatty acid desaturase gene cluster and atherosclerotic cardiovascular disease.

Properties of Dietary Fatty Acids and Implications on Cancer

Known as one of the most significant noncommunicable diseases, cancer has a high morbidity and mortality rate worldwide. Dietary fatty acids’ effect can be varied upon the structure of components. Saturated fatty acids (SFAs) and Monounsaturated fatty acids (MUFAs) intakes have positive relation with the risk of dıfferent types of cancers. However, this conclusion alters based on the type of polyunsaturated fatty acids (PUFAs). Omega-3 fatty acids illustrate protective effects against cancer, while omega-6 fatty acids have pro-inflammatory activities. Moreover, ratio of omega-3: omega-6 fatty acids plays a crucial role related to cancer. Ketogenic diet is contraindication for some types of cancer. This diet in cancer patients can be used as secondary treatment, and complications peculiarly cancer cachexia could be improved which increases life quality of cancer patients. In conclusion, decreasing the risk of cancer will be possible by shifting fatty acids consumption toward more omega-3 and less omeg-6 fatty acids and decreased intake of SFAs (via less consuming of processed foods).

Omega-3 Fatty Acids and Vitamin D Combination Affected TG Levels in Rattusnorvegicus with Limited Fat Intake

Vitamin D is a group of secosteroids that have fat-soluble properties. Vitamin D regulates calcium absorption, bone growth and remodeling, and regulates metabolic processes and immunity. Omega-3 fatty acids are a type of polyunsaturated fatty acids (PUFAs) that are essential fatty acids for humans. Omega-3 fatty acids have various positive effects on health, especially cardiovascular-related ones. This study aims to determine the effect of omega-3 fatty acid and vitamin D combination on the TG/HDL-C ratio in high fat fed Rattus norvegicus. The research design is experimental study with a post-test-only control group design. This study used 24 male rats aged 3–4 months with a body weight of 250–300 grams which were divided into four groups; negative control group, positive control group; treatment group one; and treatment group two. The high-fat diet (HFD) is an additional (emulsion) feed added to standard feed with increased fat composition. The results showed that increased triglyceride (TG) levels of 83.40 mg/dL and HDL levels of 62.60 mg/dL after consumed high-fat diet. There was a significant decrease in TG levels of 54.15 mg/dL (p=0.026) and a decrease in HDL of 53.00 mg/dL (p>0.05, α=0,05) after administration of Omega-3 and Vitamin D combination. Conclusions in this study is the intake Omega-3 and Vitamin D combination has a positive effect on TG levels. Still, this positive effect must be accompanied by limiting the fat intake to the body. Meanwhile, combining Omega-3 and Vitamin D did not significantly affect HDL levels.

1H NMR-based metabolomics study of the lipid profile of omega-3 fatty acid supplements and some vegetable oils

Omega-3 fatty acids, which consist of alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA), are a type of polyunsaturated fatty acids that are crucial for enhancing human health. These three omega-3s are regarded as vital dietary nutrients because it cannot synthesize them on its own. Therefore, they must be obtained through dietary sources. On the other hands, there are concerns regarding the quality and quantity of omega-3 in dietary sources and supplements. In this study, 1H NMR spectroscopy and multivariate analysis were harnessed for non-destructive profiling of fatty acids in commercially available omega-3 supplements and plant-based oils. Results disclosed substantial disparities in omega-3 content from 8 to over 50 %, with some revealing unexpected adulteration. Notably, in one fish oil sample DHA could not be detected indicating the possibility of adulteration. Additionally, the research delineated the fatty acid composition of plant-based oils, emphasizing variations in alpha-linolenic acid (ALA) and linoleic acid (LA) content among flaxseed, chia seed, and walnut oils. Chia seeds emerged as a rich source of ALA (57–65 %mol), while walnuts contained considerable LA (44–53 % mol). The findings emphasize the power of metabolomics as a rapid and affordable tool for finding omega-3 fatty acids content and adulteration in commercial dietary products.

Dietary polyunsaturated fatty acids intake, air pollution, and the risk of lung cancer: A prospective study in UK biobank

BackgroundEpidemiological evidence on the association between specific types of polyunsaturated fatty acids (PUFAs) intake and lung cancer risk is limited. However, whether dietary-specific PUFAs intake can modify the association between air pollutants and incident lung cancer remains unknown. MethodsCox proportional hazard models and restricted cubic spline regression were used to evaluate the associations of omega-3 PUFAs, omega-6 PUFAs and the ratio of omega-6 PUFAs to omega-3 PUFAs intake with lung cancer risk. Furthermore, we evaluated the associations between air pollutants and incident lung cancer, and whether dietary-specific PUFAs intake would modify the relationship using stratification analyses. ResultsThis study found significant associations between the risk of lung cancer and omega-3 PUFAs intake (hazard ratio [HR], 0.82; 95 % confidence interval [CI], 0.73–0.93; per 1 g/d), and omega-6 PUFAs intake (HR, 0.98; 95 % CI, 0.96–0.99; per 1 g/d). We did not observe an association between the omega-6 to omega-3 PUFAs intake ratio and incident lung cancer. With regard to air pollution, omega-3 PUFAs intake attenuated the positive relationship between nitrogen oxides (NOx) pollution and lung cancer risk, and an increased incidence of lung cancer was found only in the low omega-3 PUFAs intake group (p < 0.05). Surprisingly, PUFAs intake (regardless of omega-3 PUFAs, omega-6 PUFAs, or in total) reinforced the pro-carcinogenic effects of PM2.5 on lung cancer, and a positive association between PM2.5 pollutants and incident lung cancer was observed only in the high PUFAs groups (p < 0.05). ConclusionsHigher dietary omega-3 and omega-6 PUFAs intake was associated with a decreased risk of lung cancer in the study population. As omega-3 PUFAs have different modification effects on NOX and PM2.5 air pollution related lung cancer incidence, precautions should be taken when using omega-3 PUFAs as health-promoting dietary supplements, especially in high PM2.5 burden regions.

Types of Polyunsaturated Fatty Acids in Epididymal Adipose Tissue Are Distinguishable Using Raman Spectroscopy and Multivariate Analysis

Biological polyunsaturated fatty acids (PUFAs) are important precursors of secondary messengers that modulate inflammatory responses, cellular growth, and cholesterol metabolism. The optimal n-6/n-3 ratio is extremely important for maintaining normal homeostasis because n-3 and n-6 PUFAs are competitively metabolized. To date, a widely accepted analytical method to determine the biological n-6/n-3 ratio is gas chromatography-mass spectrometry (GC-MS) on dried whole blood samples. However, this technique has several drawbacks, including the intrusive nature of collecting blood samples, high expenses involved, and length of time required to use the GC/MS instrument. To overcome these limitations, we introduced Raman spectroscopy (RS) to distinguish PUFAs present in the epididymal adipose tissue (EAT) isolated from experimental rats that were fed three different high-fat diets (HFDs) with multivariate analysis, including principal component analysis (PCA) and linear discriminant analysis (LDA). The diets comprised HFD, HFD + perilla oil (HFD + PO [n-3 rich oil]), and HFD + corn oil (HFD + CO [n-6 rich oil]). This method allows for quantitative, label-free, noninvasive, and rapid monitoring of biochemical changes in the EAT with high sensitivity. In RS, the Raman bands of the EAT from three different diet groups (HFD, HFD + PO, and HFD + CO) detected and distinguished peaks at 1079 (C-C stretching vibration), 1300 (CH2 deformation), 1439 (CH2 deformation), 1654 (amide I), 1746 (C = O stretching vibration), and 2879 cm-1 (-C-H stretching vibration). The PCA-LDA analysis results showed that PUFAs in the EAT of animals receiving the three different dietary interventions can be determined according to the three groups (HFD, HFD + PO, and HFD + CO). In conclusion, we investigated the possibility of determining PUFA profiles in specimens using RS.

Docosahexaenoic Acid-Enhanced Autophagic Flux Improves Cardiac Dysfunction after Myocardial Infarction by Targeting the AMPK/mTOR Signaling Pathway.

Background and Purpose. Docosahexaenoic acid (DHA) is a type of polyunsaturated fatty acid enriched in cod liver oil and seaweed. It is necessary for the human body and has important functions, such as antioxidation and antiatherosclerosis activities. Long-term oral administration of DHA or the use of DHA at the initial stage of ischemia can increase the level of autophagy and exert a protective effect on neurological functions related to cerebral infarction. However, the effect of DHA on myocardial injury and cardiac insufficiency after myocardial infarction (MI) is unknown. This study was aimed at exploring whether DHA plays a protective role in AMI and its specific molecular mechanism. Experimental Method. In vitro cardiomyocyte hypoxia and in vivo MI injury models were used to determine the role of DHA in MI. Hypoxic injury induced damage in cultured neonatal mouse cardiomyocytes (NMCs). The C57BL/6J mouse MI model was established by permanent ligation of the left anterior descending branch. Main Results. DHA improved the cardiomyocyte viability of NMCs induced by hypoxia injury and reduced cell necrosis. DHA reduced infarct size, improved heart function, and reduced the degree of myocardial fibrosis in mice after MI. In addition, DHA enhanced autophagy flux and reduced apoptosis in vitro and in vivo. In addition, we found that chloroquine, an autophagy inhibitor, blocked the protective effect of DHA on cardiomyocyte apoptosis and cardiac dysfunction, indicating that DHA exerts cardioprotective effects in part by promoting autophagy flux. We also observed that DHA enhanced autophagy flux by activating the AMPK/mTOR signaling pathway. Conclusions and Significance. In conclusion, our findings indicate for the first time that DHA improves MI-induced cardiac dysfunction by promoting AMPK/mTOR-mediated autophagic flux.

A Fast and Selective Approach for Profiling Vicinal Diols Using Liquid Chromatography-Post Column Derivatization-Double Precursor Ion Scanning Mass Spectrometry.

Vicinal diols are important signaling metabolites of various inflammatory diseases, and some of them are potential biomarkers for some diseases. Utilizing the rapid reaction between diol and 6-bromo-3-pyridinylboronic acid (BPBA), a selective and sensitive approach was established to profile these vicinal diols using liquid chromatography-post column derivatization coupled with double precursor ion scan-mass spectrometry (LC-PCD-DPIS-MS). After derivatization, all BPBA-vicinal-diol esters gave a pair of characteristic isotope ions resulting from 79Br and 81Br. The unique isotope pattern generated two characteristic fragment ions of m/z 200 and 202. Compared to a traditional offline derivatization technique, the new LC-PCD-DPIS-MS method retained the capacity of LC separation. In addition, it is more sensitive and selective than a full scan MS method. As an application, an in vitro study of the metabolism of epoxy fatty acids by human soluble epoxide hydrolase was tested. These vicinal-diol metabolites of individual regioisomers from different types of polyunsaturated fatty acids were easily identified. The limit of detection (LOD) reached as low as 25 nM. The newly developed LC-PCD-DPIS-MS method shows significant advantages in improving the selectivity and therefore can be employed as a powerful tool for profiling vicinal-diol compounds from biological matrices.

Omega-3 fatty acids for the prevention of atherosclerotic cardiovascular disease.

Marine-derived omega-3 fatty acids, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), are a type of polyunsaturated fatty acids with many purported beneficial health effects including the prevention of atherosclerotic cardiovascular disease (ASCVD) events. Omega-3 fatty acid intake may be supplemented via dietary sources, as well as prescription or non-prescription products. Omega-3 fatty acids have been shown to reduce serum triglycerides, but there remains ongoing debate regarding the effect of omega-3 fatty acids on major adverse cardiovascular events in patients with established, or at risk of, ASCVD. Recent evidence from randomized, placebo-controlled trials has demonstrated that low-dose (1g daily or less) omega-3 fatty acids (DHA and EPA) do not reduce cardiovascular events or death in patients with or without established ASCVD. Contrarily, the REDUCE-IT trial demonstrated that a purified form of EPA ethyl esters (icosapent ethyl) at 4g daily reduced cardiovascular events and death in patients with ASCVD (or diabetes and multiple cardiovascular risk factors) and elevated triglycerides on background statin therapy. However, 4g daily of omega-3 carboxylic acids (DHA and EPA) did not show a cardiovascular benefit in the STRENGTH trial, which enrolled a similar population. The explanation for this observed discrepancy remains a source of contention and discourse. For now, icosapent ethyl has the most compelling evidence to support a cardiovascular benefit and should be considered in select patients who meet the REDUCE-IT criteria. Furthermore, alternative versions of omega-3 fatty acids should not be considered equivalent to icosapent ethyl. Patients taking an omega-3 fatty acid supplement should be monitored for potential adverse effects, including gastrointestinal disorders or bleeding, in addition to a possible increased risk of atrial fibrillation.

Analysis and evaluation of nutritional components of &amp;lt;italic&amp;gt;Collichthys lucidus&amp;lt;/italic&amp;gt; muscles from Mindong waters

<italic>Collichthys lucidus</italic> is an important small economic fish species in coastal areas of China. Because of fast growth, large catches and delicious taste, it is loved by people of Fujian and Zhejiang in China. At present, there are only a few studies of <italic>C</italic>. <italic>lucidus</italic> on nutrition. To improve the basic data of quality and nutritional composition of muscle in this species, this study analyzed and evaluated the nutrient composition of <italic>C</italic>. <italic>lucidus</italic> muscles from Mindong waters. Nutritional components in muscle of <italic>C</italic>. <italic>lucidus</italic> were tested and analyzed with routine methods. Samples of 30 wild individuals, with (12.45±1.25) cm in body length and (37.15±13.25) g in body weight, were collected from Mindong waters during the reproductive season. The results showed that contents of moisture, crude ash, crude protein and crude fat of fresh muscles were (77.70±0.21)%, (1.49±0.59)%, (17.21±0.27)% and (0.56±0.05)%, respectively. There were 17 common amino acids found in muscles, including 7 essential amino acids (except Trp). In fresh sample, the total content of amino acids was (17.01±0.11)%, the content of essential amino acids was (6.09±0.06)%; in dry sample, the total content of amino acids was (76.30± 0.44)%; the content of essential amino acids was (27.33±0.29)%; the percentage of essential amino acids in total amino acids was 35.82%; the ratio of amino acids to no-essential amino acids (EAA/ NEAA) was 66.73%. The constitutional rate of the essential amino acids accorded with the FAO/WHO standard fundamentally. According to nutrition evaluation in amino acids score (AAS) and chemical score (CS), the first limited amino acid was Val, and the second limited amino acids were Leu and Phe+Tyr; the essential amino acids index (EAAI) was 67.04. In dry sample, the content of four kinds delicious amino acids was (26.24±0.01)%, and the percentage of delicious amino acids in total amino acids was 34.40%. 27 fatty acids were found in muscle of <italic>C</italic>. <italic>lucidus</italic>. There were 12 types of saturated fatty acids, accounting for (56.48±0.10)% of the total fatty acids. The content of C18∶0 in saturated fatty acids was the highest, accounting for (32.77±0.42)% of the total fatty acids. There were 7 types of monounsaturated fatty acids, accounting for (13.22±0.12)% of the total fatty acids, and 8 types of polyunsaturated fatty acids, accounting for (30.31±0.18)% of the total fatty acids. The percentages of EPA and DHA in total fatty acids of <italic>C</italic>. <italic>lucidus</italic> were (8.23±0.14)% and (13.22±0.12)%, respectively. The composition of trace elements in muscles of <italic>C</italic>. <italic>lucidus</italic> was reasonable. Therefore, <italic>C</italic>. <italic>lucidus</italic> is delicious fish species with balanced nutrition and relatively high nutritional value, which deserves further exploitation and popularization.

The under-appreciated fats of life: the two types of polyunsaturated fats.

There are two types of polyunsaturated fatty acids (i.e. fats that contain multiple carbon-carbon double bonds) - omega-6 and omega-3. They are not interconvertible, and they contribute 'double-bonded carbons' to different depths in bilayer membranes, with different effects on membrane processes. This Commentary emphasises the importance of these fats for biological membrane function and examines their evolution and biochemistry. Omega-6 and omega-3 fatty acids are separately essential in the diet of animals, and they pass up the food chain largely from plants, with 'seeds' being a prevalent source of omega-6, and 'leaves' a prevalent source of omega-3. The dietary balance between these fatty acids has a strong influence on membrane composition. Although this aspect of diet has been little investigated outside of the biomedical field, emerging evidence shows it can alter important physiological capacities of animals (e.g. exercise endurance and adiposity), which has implications for activities such as avian migration and hibernation and torpor, as well as significant implications for human health. This Commentary will focus on the separate effects of omega-3 and omega-6 on membrane properties and will emphasise the importance of the balance between these two fatty acids in determining the function of biological membranes; I hope to convince the reader that fats should be considered first and foremost as the basic unit of biological membranes, and secondarily as a means of energy storage.

Polyunsaturated fatty acids in reducing cardiovascular risk

Cardiovascular diseases are the leading cause of mortality worldwide. Prevention, diagnosis and treatment of these diseases are one of the major challenges in modern medicine. Despite a large number of pharmacological agents significantly reducing the cardiovascular risk, it is still high in many patients. Due to the multifactorial aetiology and complex pathomechanism of cardiovascular diseases, the development of a more effective therapy remains an open issue. It was found in the 1980s that a diet rich in polyunsaturated fatty acids, eicosapentaenoic acid and docosahexaenoic acid in particular, was associated with a lower incidence of cardiovascular diseases. For this reason, polyunsaturated fatty acids have become the subject of many clinical trials aimed at understanding their mechanism of action and determining their exact impact on cardiovascular risk. Polyunsaturated fatty acids are known to affect many aspects that are key factors in the development of cardiovascular disease. They are characterised mainly by a positive effect on the structure and functioning of cell membranes, the ability to reduce inflammation and blood pressure, anticoagulant and antiplatelet effects, antiarrhythmic activity, the ability to improve myocardial contractility and a beneficial effect on the lipid profile. The latest analyses of the available clinical trials show that these compounds reduce cardiovascular risk in both primary and secondary prevention. Therefore, they represent a promising therapeutic option. It is worth noting that the effect seems to depend on the type of polyunsaturated fatty acids, their dose and individual factors. Nevertheless, this issue is extremely complex and requires further research to fully understand the mechanism of action and establish ideal therapeutic doses to improve patient prognosis.

Fatty acid profiles of Paper Squid (Loligo edulis, Hoyle)

Squid is one of the fisheries products with high production volume. It has the same characteristics as other fishery products, which is highly perishable in nature. Therefore it is important to optimize squid utilization. Diversification of squid products can be done into value-added products such as paper squid. The aim of this study was to investigate the fatty acids profile contained in paper squid (Loligo edulis, Hoyle). Analysis of fatty acids composition in squid was done by the gas chromatography method. The results showed that the fatty acids detected in paper squid consisted of 10 types of saturated fatty acids, 7 types of monounsaturated fatty acids, and 8 types of polyunsaturated fatty acids. The highest content of saturated fatty acids is palmitic acid, which is 7.45%. The highest content of monounsaturated fatty acid is oleic acid, which is 0.79%. The highest content of polyunsaturated fatty acids is docosahexaenoic acid, which is 22.57%.

Erythrocyte Membrane Polyunsaturated Fatty Acids Are Associated with Incidence of Metabolic Syndrome in Middle-Aged and Elderly People–An 8.8-Year Prospective Study

Background:The total and specific types of polyunsaturated fatty acids (PUFAs) related to metabolic syndrome (MetS) remain inconsistent. Objective:We assessed the association of erythrocyte n–3 and n–6 PUFAs with MetS and the components of MetS in a cohort population. Methods:This prospective analysis included 2754 participants (aged 40–75 y) from the Guangzhou Nutrition and Health Study (2008–2019) in China. Erythrocyte PUFAs at baseline were measured using gas chromatography. MetS was assessed every 3 y according to the updated National Cholesterol Education Program Adult Treatment Panel III criteria. Multivariable Cox proportional hazard models were used to evaluate HRs and 95% CIs. Results:We identified 716 incident cases of MetS. The primary analyses showed that the HRs (95% CIs) of MetS (tertile 3 versus 1) were 0.67 (0.56, 0.80) for n–3 PUFAs and 0.70 (0.58, 0.85) for n–6 PUFAs (all Ps trend <0.001). The secondary outcomes showed that, higher erythrocyte very-long-chain (VLC) PUFAs [20:3n–3, docosapentaenoic acid (DPA), docosahexaenoic acid (DHA), arachidonic acid (ARA), and 22:4n–6], but lower α-linolenic acid (ALA) and α-linolenic acid (GLA), tended to be associated with lower incidences of MetS and its components; among individual MetS components, the associations of PUFAs were more pronounced for hypertriglyceridemia (HTG) and hypertension, followed by low high-density lipoproten (HDL) cholesterol. Significantly higher concentrations of n–3 PUFAs (total, DPA, and DHA) and n–6 PUFAs (total, ARA, and 22:4) were observed in participants with improved (versus progressed) status of MetS (all Ps trend ≤0.003). Conclusion:This study reveals that higher erythrocyte VLC n–3 and n–6 PUFAs, but lower 18-carbon PUFAs (ALA and GLA), are associated with lower risks of MetS components (HTG, hypertension, and low HDL cholesterol) and thereby lower MetS incidence in Chinese adults.

Mediterranean Diet and Osteoarticular Diseases

Background: Besides the well-known positive effect on the reduction of the risk of cardiovascular diseases, in the latest decades growing evidence has accumulated on the beneficial effects of MD on various aspects of health outcomes. Nevertheless, data concerning the existence of a direct positive effect of MD, irrespective of its beneficial effect on body weight, in osteo-articular diseases, are still controversial. In osteo-articular diseases, a pro-inflammatory environment is highlighted, with an increased systemic levels of pro-inflammatory cytokines. Objective: Our objective is to investigate the effects of adherence to the Mediterranean diet and osteo-articular diseases. Conclusion: Many foods included in MD, have anti-inflammatory properties, due to the presence of nutrients, such as polyunsaturated (PUFA) and monounsaturated (MUFA) fats. The two types of polyunsaturated fatty acids, omega-3 and omega-6, have opposing effects on the inflammatory process. Omega-6 stimulates the production of pro-inflammatory cytokines, while omega-3 fatty acids exert anti-inflammatory effects, including significant reductions in the release of pro-inflammatory cytokines. Some studies have shown that the dietary pattern of MD consumption has an important role in the prevention and development of inflammatory arthritis. Nevertheless, the possible influence of MD on chronic osteo-articular diseases is very limited, this review updates the main experimental and clinical evidences concerning the potential beneficial effects of the Mediterranean Diet on the most diffuse osteo-articular chronic and degenerative joint disease.

A comparative study of food selectivity of the benthic copepod Tigriopus japonicus and the pelagic copepod Paracyclopina nana: A genome-wide identification of fatty acid conversion genes and nitrogen isotope investigation

A comparative study of food selectivity of the benthic copepod Tigriopus japonicus and the pelagic copepod Paracyclopina nana was performed by feeding four different microalgae (Tetraselmis suecica, Isochrysis galbana, Chlorella sp., and Nannochloropsis oculata). To examine whether the morphological characteristics of the microalga could influence the food selectivity, we investigated the movement, color, and size of the microalgae. The result indicated significant differences only in the movement of microalga. However, no significant differences in most of the microalgae were observed in feeding rate determination in 24 h, indicating plenty amounts of microalgae were administered to both copepods. In the T. suecica- and I. galbana-fed groups, no significant nitrogen isotopic turnover was observed, indicating both microalgae might be suitable for experimental copepods. However, the difference in the isotopic ratio of N. oculata and N. oculata-fed copepods showed that N. oculata was not a good food source. Various types of polyunsaturated fatty acids were successfully synthesized. However, the class of fatty acid conversion genes was different and the transcript level showed different trends according to each microalgal species in the two copepods. In developmental time, T. japonicus was not severely affected by the food types, while in P. nana, only T. suecica-fed group showed typical development progression. For further verification, both copepods were exposed to frozen-T. suecica. The result showed that T. japonicus was not affected by the frozen-T. suecica-fed condition, but no sign of development in P. nana was shown, suggesting that P. nana could not detect non-motile microalgae.

Comprehensive and semi-quantitative analysis of carboxyl-containing metabolites related to gut microbiota on chronic kidney disease using 2-picolylamine isotopic labeling LC-MS/MS

Carboxyl-containing metabolites, such as bile acids and fatty acids, have many important functions and microbiota is involved in the production of them. In the previous study, we found that the chronic kidney disease (CKD) model mice raised under germ-free conditions provided more severe renal damage than the mice with commensal microbiota. However, the precise influence by the microbiome and carboxyl-containing metabolites to the renal functions is unknown. In this study, we aimed to develop a novel chemical isotope labeling-LC-MS/MS method using the 2-picolylamine and its isotopologue and applied the analysis of effects of microbiome and CKD pathophysiology. The developed semi-quantitative method provided the high accuracy not inferior to the absolute quantification. By comparing of four groups of mice, we found that both microbiota and renal function can alter the composition and level of these metabolites in both plasma and intestine. In particular, the intestinal level of indole-3-acetic acid, short-chain fatty acids and n-3 type of polyunsaturated fatty acid, which play important roles in the endothelial barrier function, were significantly lower in germ-free conditions mice with renal failure. Accordingly, it is suggested these metabolites might have a renoprotective effect on CKD by suppressing epithelial barrier disruption.

Abstract 639: Dietary polyunsaturated fatty acids intake and pancreatic cancer risk in understudied populations

Abstract Background: Pancreatic cancer (PC) is one of the deadliest malignancies. Lab based research suggests that two types of polyunsaturated fatty acids (PUFA), n-3 and n-6 PUFA, may have opposing effects on PC carcinogenesis. However, human evidence on the role of dietary PUFA intake in PC risk is inconsistent. Previous epidemiological studies on this topic were conducted primarily among Whites and included few individuals from low socioeconomic status (SES). The exposure patterns of n-3 and n-6 PUFA differ across racial groups, with African Americans (AAs) in the high end and Asians in the low end of range. To better characterize the associations of PUFA with PC risk, we conducted a nested case-control study focusing on understudied Asians and low SES AAs and Whites. Methods: We performed a nested case-control study within three population-based prospective cohort studies: the Shanghai Women’s Health Study (SWHS), Shanghai Men’s Health Study (SMHS), and Southern Community Cohort Study (SCCS). Dietary PUFA intakes and other variables were collected from the baseline dietary and other questionnaires. Participants were followed up through annual linkage to cancer registries. Controls were matched to cases on age, sex, and blood sample availability in SWHS/SMHS, and age, sex, race, and enrollment location in SCCS, using incidence density sampling (case-to-control ratio:1:4). Included in the study are 244 cases and 973 controls of Asian females in SWHS, 189 cases and 755 controls of Asian males in SMHS, and 307 cases and 1,228 controls in SCCS (including 219 cases and 876 controls of AAs). The PUFA intake was adjusted for total energy intake using the residual method. Conditional logistic regression analyses were performed to estimate the association of PC risk with dietary PUFA consumption after adjusting for potential covariates. Results: The average dietary intake (mean ± SD; g/day) of n-3 and n-6 PUFA were 1.0 ± 0.5 and 6.3 ± 3.1, 1.1 ± 0.5 and 7.2 ± 3.0, and 2.0 ± 1.2 and 19.3 ± 11.7 in the controls of SWHS, SMHS and SCCS, respectively. We observed that in Chinese men, high intakes of certain n-3 PUFA were significantly associated with increased PC risk. The adjusted odds ratio (OR) (95% confidence interval (CI)) comparing the highest versus lowest quartile of docosapentaenoic acid (DPA) was 1.79 (1.10-2.93), with a p for trend across quartiles of 0.02. For docosahexaenoic acid (DHA), the OR 4th vs. 1st quartile (95% CI) = 1.71 (1.06-2.78) (p for trend = 0.04). For marine n-3 PUFA, the OR 4th vs. 1st quartile (95% CI) = 1.69 (1.03-2.76) (p for trend = 0.04). There was no significant association for n-6 PUFA. No significant association was observed for n-3 or n-6 PUFA with PC risk in SWHS or SCCS. Conclusions: In a nested case-control study, we observed that in Chinese men, the dietary intake of overall marine n-3 PUFA, DPA, and DHA were positively associated with PC risk. Such associations were not observed in Chinese women or low SES AAs/Whites. Citation Format: Lang Wu, Wei Zheng, William J. Blot, Mark D. Steinwandel, Wanqing Wen, Yong-Bing Xiang, Yu-Tang Gao, Hong-Lan Li, Rachael Stolzenberg-Solomon, Harvey J. Murff, Xiao-Ou Shu. Dietary polyunsaturated fatty acids intake and pancreatic cancer risk in understudied populations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 639.

Chemical Characterization and Oxidative Stability of Medium- and Long-Chain Fatty Acid Profiles in Tree-Borne Seed Oils.

This study was undertaken to evaluate chemical characteristics and oxidative stability of tree-borne seed oils. A total of 15 different fatty acids were identified in six tree-borne seed oils, which included seven types of saturated fatty acids, four types of monounsaturated fatty acids, and four types of polyunsaturated fatty acids. Japanese camphor tree (JCT) had a high content of medium-chain fatty acids (97.94 ± 0.04%), in which fatty acid composition was distinct from those of the other five plant seed oils. Overall, contents of tocopherols, a type of fat-soluble vitamin, ranged between 3.82 ± 0.04 mg/100 g and 101.98 ± 1.34 mg/100 g, respectively. Phytosterol contents ranged from 117.77 ± 1.32 mg/100 g to 479.45 ± 4.27 mg/100 g, respectively. Of all tree-borne seed oils, β-sitosterol was the phytosterol at the highest concentration. Contents of unsaponifiables were between 0.13 ± 0.08 and 2.01 ± 0.02, and values of acid, peroxide, and p-anisidine were between 0.79 ± 0.01 and 38.94 ± 0.24 mg KOH/g, 3.53 ± 0.21 and 127.67 ± 1.79 meq/kg, and 2.07 ± 0.51 and 9.67 ± 0.25, respectively. Oxidative stability of tree-borne seed oils was assessed through measurement of oxidation-induction periods. These results should serve as a foundation to identify the potential of tree-borne seed oils in industrial application as well as in providing fundamental data.

JA, a new type of polyunsaturated fatty acid isolated from Juglans mandshurica Maxim, limits the survival and induces apoptosis of heptocarcinoma cells.

Juglans mandshurica Maxim (Juglandaceae) is a famous folk medicine for cancer treatment and some natural compounds isolated from it have been studied extensively. Previously we isolated a type of ω-9 polyunsaturated fatty acid (JA) from the bark of J. mandshurica, however little is known about its activity and the underlying mechanisms. In this study, we studied anti-tumor activity of JA on several human cancer cell lines. Results showed that JA is cytotoxic to HepG2, MDA-MB-231, SGC-7901, A549 and Huh7 cells at a concentration exerting minimal toxic effects on L02 cells. The selective toxicity of JA was better than other classical anti-cancer drugs. Further investigation indicated that JA could induce cell apoptosis, characterized by chromatin condensation, DNA fragmentation and activation of the apoptosis-associated proteins such as Caspase-3 and PARP-1. Moreover, we investigated the cellular apoptosis pathway involved in the apoptosis process in HepG2 cells. We found that proteins involved in mitochondrion (cleaved-Caspase-9, Apaf-1, HtrA2/Omi, Bax, and Mitochondrial Bax) and endocytoplasmic reticulum (XBP-1s, GRP78, cleaved-Caspase-7 and cleaved-Caspase-12) apoptotic pathways were up-regulated when cells were treated by JA. In addition, a morphological change in the mitochondrion was detected. Furthermore, we found that JA could inhibit DNA synthesis and induce G2/M cell cycle arrest. The expression of G2-to-M transition related proteins, such as CyclinB1 and phosphorylated-CDK1, were reduced. In contrast, the G2-to-M inhibitor p21 was increased in JA-treated cells. Overall, our results suggest that JA can induce mitochondrion- and endocytoplasmic reticulum-mediated apoptosis, and G2/M phase arrest in HepG2 cells, making it a promising therapeutic agent against hepatoma.