Association between serum free fatty acid levels and possible related factors in patients with type 2 diabetes mellitus and acute myocardial infarction

Pseudo-targeted metabolic profile differences between emergency patients with type 1 and type 2 myocardial infarction diagnosed by optical coherence tomography

BACKGROUND

It is difficult to distinguish type 2 myocardial infarction (T2MI) from type 1 myocardial infarction (T1MI), although their management varies.

OBJECTIVES

Using optical coherence tomography (OCT) and pseudo-targeted metabolomics to identify biomarkers, investigate metabolic differences, and establish a T2MI subclassification.

METHODS

Among 1519 patients with MI, 97 T2MI patients are identified who are 1:1 matched with 97 T1MI patients after considering age, gender, ST-segment elevation, time from onset to coronary angiography, and hs-cTnI on admission by propensity score matching. Plasma pseudo-targeted metabolomics at baseline was determined.

RESULTS

The clinical characteristics of the two groups were comparable, while the T1MI showed more severe coronary lesions than T2MI according to OCT imaging. 90 differential metabolites were identified between the two groups, among 1027 endogenous metabolites in 20 classes. N-Acetyl-L-Leucine, free fatty acid (15:1), Thymidine-5'-triphosphate, Mevalonic acid 5-pyrophosphate, and five oligopeptides were candidate biomarkers (AUC ≥ 0.85) distinguishing T2MI from T1MI. 12 KEGG pathways showed significant differences, mainly involving amino acid, nucleotide, and their derivatives metabolism, and signaling pathways such as mTOR, cGMP-PKG, and cAMP. Other differences were observed in TCA cycle (P = 0.08) and ROS (P = 0.05). Proteolysis and coronary heart disease risk lipid level were lower in T2MI. T2MI had a decrease of differential abundance score in almost all the KEGG enrichment pathways. Furthermore, T2MI can be subdivided into three subtypes by hierarchical cluster analysis of AUCs with causes/triggers of T2MI.

CONCLUSIONS

There are significant metabolic profile differences between T1MI and T2MI. Several candidate metabolic biomarkers can effectively distinguish the two groups.

CLINICAL TRIAL REGISTRATION

ClinicalTrials. gov NCT03297164.

The Associations of Individual and Subclasses of Nonesterified Fatty Acids With Disability, and Mobility Limitation in Older Adults: The Cardiovascular Health Study

BACKGROUND

We sought to determine the associations between individual nonesterified fatty acids (NEFAs) and disability and mobility limitation.

METHODS

We studied 1 734 participants in the Cardiovascular Health Study (CHS), an ongoing population-based cohort study of community-living older American adults. We measured 35 individual NEFA species in fasting serum samples obtained at the 1996-1997 clinic visit. Using yearly assessments of activities of daily living and self-reported mobility, we identified participants with incident disability or mobility limitation during 15 years of follow-up. Cox proportional hazards regression models were used to determine the associations between per SD increment in the individual NEFAs and incident disability and mobility limitations with adjustment for potential confounding factors.

RESULTS

Higher concentrations of total and a broad range of individual NEFA species were associated with risk of disability and mobility limitation (disability: HR per SD of total NEFA [SD = 174.70] = 1.11, 95% CI = 1.04-1.18, p = .001; mobility limitation: HR per SD of total NEFA = 1.09, 95% CI = 1.02-1.16, p = .01). Among individual saturated NEFAs (SFAs), myristic (14:0) and palmitic (16:0) acids were significantly associated with higher risk of both disability and mobility limitations, but longer-chain FAs were not. Most individual monounsaturated (MUFA), n-6 polyunsaturated fatty acids (PUFAs), and trans FAs were positively significantly associated with higher risks of both disability and mobility limitation. In contrast, most n-3 PUFA species were not associated with disability or mobility limitation.

CONCLUSIONS

Higher risks of disability and mobility limitation were observed for proinflammatory intermediate-chain SFAs, MUFAs, n-6 PUFAs, and trans FAs. Our findings indicated no significant association for anti-inflammatory n-3 PUFAs.

Non-esterified fatty acids and risk of peripheral artery disease in older adults: The cardiovascular health study

BACKGROUND AND AIMS

Non-esterified fatty acids have been implicated in the pathogenesis of diabetes and cardiovascular disease. No longitudinal study has assessed their effects on peripheral artery disease (PAD). We determined the relationships between NEFAs and incident clinical PAD and abnormal ankle-brachial index (ABI) in a population-based cohort of older persons.

METHODS

We evaluated 4575 community living participants aged >65 years who underwent measurement of circulating NEFAs in fasting specimens and ABI in 1992-1993. Participants were assessed annually for clinical PAD until 2015 and underwent repeat ABI in 1998-1999. We used Cox proportional hazards regression to model the associations between NEFAs and risk of clinical PAD and logistic regression to model the associations of NEFAs with incident abnormal ABI.

RESULTS

Mean age was 74.8 years, 59% were female, and 17% were Black. NEFAs were associated with higher risk of clinical PAD in unadjusted and adjusted models. The adjusted hazard ratios for incident clinical PAD were 1.51 (95%CI = 1.06-2.13, p = 0.02) across extreme tertiles, and 1.14 (95%CI = 0.99-1.31, p = 0.08) per standard deviation higher NEFA. The corresponding odds ratios for abnormal ABI were 0.95 (95%CI = 0.69-1.32, p = 0.76) across extreme tertiles, and 1.03 (95%CI = 0.89-1.20, p = 0.68) per standard deviation higher NEFA. Relationships appeared similar irrespective of sex, race, or pre-existing cardiovascular disease, but were stronger later than earlier in follow-up.

CONCLUSIONS

Higher serum levels of NEFAs are significantly associated with increased likelihood of clinical PAD over long-term follow-up but not with 6-year decline in ABI. NEFAs may offer a potential target for intervention against clinical PAD.

Serum growth differentiation factor-15 and non-esterified fatty acid levels in patients with coronary artery disease and hyperuricemia

BACKGROUND

High serum NEFA and GDF-15 are risk factors for CAD and have been linked to detrimental cardiovascular events. It has been hypothesized that hyperuricemia causes CAD via the oxidative metabolism and inflammation. The current study sought to clarify the relationship between serum GDF-15/NEFA and CAD in individuals with hyperuricemia.

METHODS

Blood samples collected from 350 male patients with hyperuricemia(191 patients without CAD and 159 patients with CAD, serum UA > 420 μmol/L) to measure serum GDF-15 and NEFA concentrations with baseline parameters.

RESULTS

Serum circulating GDF-15 concentrations(pg/dL) [8.48(6.67,12.73)] and NEFA levels(mmol/L) [0.45(0.32,0.60)] were higher in hyperuricemia patients with CAD. Logistic regression analysis revealed that the OR (95% CI) for CAD were 10.476 (4.158, 26.391) and 11.244 (4.740, 26.669) in quartile 4 (highest) respectively. The AUC of the combined serum GDF-15 and NEFA was 0.813 (0.767,0.858) as a predictor of whether CAD occurred in male with hyperuricemia.

CONCLUSIONS

Circulating GDF-15 and NEFA levels correlated positively with CAD in male patients with hyperuricemia and measurements may be a useful clinical adjunct.

Recent Advances in Cardiovascular Diseases Research Using Animal Models and PET Radioisotope Tracers

Cardiovascular diseases (CVD) is a collective term describing a range of conditions that affect the heart and blood vessels. Due to the varied nature of the disorders, distinguishing between their causes and monitoring their progress is crucial for finding an effective treatment. Molecular imaging enables non-invasive visualisation and quantification of biological pathways, even at the molecular and subcellular levels, what is essential for understanding the causes and development of CVD. Positron emission tomography imaging is so far recognized as the best method for in vivo studies of the CVD related phenomena. The imaging is based on the use of radioisotope-labelled markers, which have been successfully used in both pre-clinical research and clinical studies. Current research on CVD with the use of such radioconjugates constantly increases our knowledge and understanding of the causes, and brings us closer to effective monitoring and treatment. This review outlines recent advances in the use of the so-far available radioisotope markers in the research on cardiovascular diseases in rodent models, points out the problems and provides a perspective for future applications of PET imaging in CVD studies.

Plasma Quantitative Lipid Profiles: Identification of CarnitineC18:1-OH, CarnitineC18:2-OH and FFA (20:1) as Novel Biomarkers for Pre-warning and Prognosis in Acute Myocardial Infarction

This study was aimed to determine the association between potential plasma lipid biomarkers and early screening and prognosis of Acute myocardial infarction (AMI). In the present study, a total of 795 differentially expressed lipid metabolites were detected based on ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Out of these metabolites, 25 lipid metabolites were identified which showed specifical expression in the AMI group compared with the healthy control (HC) group and unstable angina (UA) group. Then, we applied the least absolute shrinkage and selection operator (LASSO) and support vector machine-recursive feature elimination (SVM-RFE) methods to obtain three lipid molecules, including CarnitineC18:1-OH, CarnitineC18:2-OH and FFA (20:1). The three lipid metabolites and the diagnostic model exhibited well predictive ability in discriminating between AMI patients and UA patients in both the discovery and validation sets with an area under the curve (AUC) of 0.9. Univariate and multivariate logistic regression analyses indicated that the three lipid metabolites may serve as potential biomarkers for diagnosing AMI. A subsequent 1-year follow-up analysis indicated that the three lipid biomarkers also had prominent performance in predicting re-admission of patients with AMI due to cardiovascular events. In summary, we used quantitative lipid technology to delineate the characteristics of lipid metabolism in patients with AMI, and identified potential early diagnosis biomarkers of AMI via machine learning approach.

Nonesterified Fatty Acids and Hospitalizations Among Older Adults: The Cardiovascular Health Study

BACKGROUND

We sought to determine associations between total serum concentrations of nonesterified fatty acids (NEFAs) and incident total and cause-specific hospitalizations in a community-living cohort of older adults.

METHODS

We included 4715 participants in the Cardiovascular Health Study who had fasting total serum NEFA measured at the 1992/1993 clinic visit and were followed for a median of 12 years. We identified all inpatient admissions requiring at least an overnight hospitalization and used primary diagnostic codes to categorize cause-specific hospitalizations. We used Cox proportional hazards regression models to determine associations with time-to-first hospitalization and Poisson regression for the rate ratios (RRs) of hospitalizations and days hospitalized.

RESULTS

We identified 21 339 hospitalizations during follow-up. In fully adjusted models, higher total NEFAs were significantly associated with higher risk of incident hospitalization (hazard ratio [HR] per SD [0.2 mEq/L] = 1.07, 95% confidence interval [CI] = 1.03-1.10, p < .001), number of hospitalizations (RR per SD = 1.04, 95% CI = 1.01-1.07, p = .01), and total number of days hospitalized (RR per SD = 1.06, 95% CI = 1.01-1.10, p = .01). Among hospitalization subtypes, higher NEFA was associated with higher likelihood of mental, neurologic, respiratory, and musculoskeletal causes of hospitalization. Among specific causes of hospitalization, higher NEFA was associated with diabetes, pneumonia, and gastrointestinal hemorrhage.

CONCLUSIONS

Higher fasting total serum NEFAs are associated with a broad array of causes of hospitalization among older adults. While some of these were expected, our results illustrate a possible utility of NEFAs as biomarkers for risk of hospitalization, and total days hospitalized, in older adults. Further research is needed to determine whether interventions based on NEFAs might be feasible.

Metabolome-Genome-Wide Association Study (mGWAS) Reveals Novel Metabolites Associated with Future Type 2 Diabetes Risk and Susceptibility Loci in a Case-Control Study in a Chinese Prospective Cohort

In a Chinese prospective cohort, 500 patients with new-onset type 2 diabetes (T2D) within 4.61 years and 500 matched healthy participants are selected as case and control groups, and randomized into discovery and validation sets to discover the metabolite changes before T2D onset and the related diabetogenic loci. A serum metabolomics analysis reveals that 81 metabolites changed significantly before T2D onset. Based on binary logistic regression, eight metabolites are defined as a biomarker panel for T2D prediction. Pipecolinic acid, carnitine C14:0, epinephrine and phosphatidylethanolamine 34:2 are first found associated with future T2D. The addition of the biomarker panel to the clinical markers (BMI, triglycerides, and fasting glucose) significantly improves the predictive ability in the discovery and validation sets, respectively. By associating metabolomics with genomics, a significant correlation (p < 5.0 × 10-8) between eicosatetraenoic acid and the FADS1 (rs174559) gene is observed, and suggestive correlations (p < 5.0 × 10-6) between pipecolinic acid and CHRM3 (rs535514), and leucine/isoleucine and WWOX (rs72487966) are discovered. Elevated leucine/isoleucine levels increased the risk of T2D. In conclusion, multiple metabolic dysregulations are observed to occur before T2D onset, and the new biomarker panel can help to predict T2D risk.

Association of plasma free fatty acids levels with the presence and severity of coronary and carotid atherosclerotic plaque in patients with type 2 diabetes mellitus

BACKGROUND

Previous studies have suggested that patients with diabetes mellitus (DM) have higher prevalence of atherosclerotic cardiovascular disease (ASCVD), and plasma levels of free fatty acids (FFAs) are a useful marker for predicting ASCVD. We hypothesized that FFAs could predict both coronary and carotid lesions in an individual with type 2 DM (T2DM). The present study, hence, was to investigate the relation of plasma FFA level to the presence and severity of coronary and carotid atherosclerosis in patients with T2DM.

METHODS

Three hundred and two consecutive individuals with T2DM who have received carotid ultrasonography and coronary angiography due to chest pain were enrolled in this study. Plasma FFAs were measured using an automatic biochemistry analyzer. Coronary and carotid severity was evaluated by Gensini score and Crouse score respectively. Subsequently, the relation of FFA levels to the presence and severity of coronary artery disease (CAD) and carotid atherosclerotic plaque (CAP) in whole individuals were also assessed.

RESULTS

Increased plasma FFA levels were found in the groups either CAD or CAP compared to those without. Patients with higher level of FFAs had a higher CAD (89.9%) and elevated prevalence of CAP (69.7%). And also, patients with higher level of FFAs had a higher Gensini and Crouse scores. Multivariate regression analysis showed that FFA levels were independently associated with the presence of CAD and CAP (OR = 1.83, 95%CI: 1.27-2.65, P = 0.001; OR = 1.62, 95%CI: 1.22-2.14, P = 0.001, respectively). The area under the curve (AUC) was 0.68 and 0.65 for predicting the presence of CAD and CAP in patients with DM respectively.

CONCLUSIONS

The present study firstly indicated that elevated FFA levels appeared associated with both the presence and severity of CAD and CAP in patients with T2DM, suggesting that plasma FFA levels may be a useful biomarker for improving management of patients with T2DM.

Non-esterified fatty acids and telomere length in older adults: The Cardiovascular Health Study

Background

Telomeres shorten as organisms age, placing limits on cell proliferation and serving as a marker of biological aging. Non-esterified fatty acids (NEFAs) are a key mediator of age-related metabolic abnormalities. We aimed to determine if NEFAs are associated with telomere length in community-living older adults.

Material and methods

We cross-sectionally studied 1648 participants of the Cardiovascular Health Study (CHS) who underwent concomitant telomere length measurement from a sample of 4715 participants who underwent measurement of circulating total fasting NEFAs in stored specimens from their 1992-3 clinic visit. We used linear regression and inverse probability weighting to model telomere length as a function of NEFAs with adjustment for age, gender, race, clinic, BMI, marital status, smoking status, alcohol intake, diabetes status, years of education, hypertension status, prevalent cardiovascular disease, C-reactive protein, total adiponectin, albumin, fetuin-A, fasting insulin, eGFR, total cholesterol, HDL-cholesterol, triglycerides, and general health status.

Results

Higher NEFAs were significantly associated with shorter telomere length, after adjusting for age, gender, race, and clinic site (β = −0.034; SE = 0.015; P = 0.02). Estimates remained similar in fully adjusted models where each SD of NEFA increment was associated with 0.042 kilobase (kb) pairs shorter telomere length (standard error = 0.016; P = 0.007); for comparison the coefficient for a single year of age in the same model was −0.017. These results were similar in strata of sex, and waist circumference although they tended to be strongest among participants in the youngest tertile of age (β = -0.079; SE = 0.029; P = 0.01).

Conclusions

In this population-based cohort of community-living elders, we observed a significant inverse association between NEFAs and telomere length. If confirmed, NEFAs may represent a promising target for interventions to slow biological aging.

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Shorter telomere lengths have been linked to accelerated aging and disease.

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Oxidative stress and inflammation drives telomere length shortening.

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Non-esterified fatty acids induce oxidative stress and inflammation.

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Higher levels of non-esterified fatty acids were associated with shorter telomeres.

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Non-esterified fatty acids may be an intervention target to slow biological aging.

Non-Esterified Fatty Acids and Risks of Frailty, Disability, and Mobility Limitation in Older Adults: The Cardiovascular Health Study

BACKGROUND/OBJECTIVES

Non-esterified fatty acids (NEFAs) play central roles in the relationship between adiposity and glucose metabolism, and they have been implicated in the pathogenesis of cardiovascular disease, but few studies have assessed their effects on complex geriatric syndromes like frailty that cross multiple organ systems. We sought to determine the relationships between NEFAs and incident frailty, disability, and mobility limitation in a population-based cohort of older persons.

METHODS

We analyzed 4,710 Cardiovascular Health Study (CHS) participants who underwent measurement of circulating total fasting NEFAs in 1992-1993 and were assessed for frailty in 1996-1997 and for disability and mobility limitation annually. We used ordinal logistic regression to model incident frailty, linear regression to model components of frailty, and Cox regression to model disability and mobility limitation in relation to baseline NEFAs. To ensure proportional hazards, we truncated follow-up at 9 years for disability and 6.5 years for mobility limitation.

RESULTS

A total of 42 participants became frail and 510 became pre-frail over a 4-year period, and we documented 1,720 cases of disability and 1,225 cases of mobility limitation during follow-up. NEFAs were positively associated in a dose-dependent manner with higher risks of incident frailty, disability, and mobility limitation. The adjusted odds ratios for frailty were 1.37 (95% confidence interval [CI] = 1.01-1.86; P = .04) across extreme tertiles and 1.17 (95% CI = 1.03-1.33; P = .01) per standard deviation increment. The corresponding hazard ratios for incident disability were 1.14 (95% CI = 1.01-1.30; P = .04) and 1.11 (95% CI = 1.06-1.17; P < .0001); those for incident mobility limitation were 1.23 (95% CI = 1.06-1.43; P = .006) and 1.15 (95% CI = 1.08-1.22; P < .0001). Results were largely consistent among both men and women. Among individual components of frailty, NEFAs were significantly associated with self-reported exhaustion (β = .07; standard error = .03; P = .02).

CONCLUSION

Circulating NEFAs are significantly associated with frailty, disability, and mobility limitation among older adults. These results highlight the broad spectrum of adverse health issues associated with NEFA in older adults.

Significance of plasma free fatty acid level for assessing and diagnosing acute myocardial infarction

Aim: To clarify the diagnostic value of the circulating free fatty acid (FFA) level for acute myocardial infarction (AMI) in coronary heart disease patients. Methods & results: A total of 1776 patients were screened by coronary angiography from October 2014 to February 2016. The plasma FFA level was significantly higher in coronary heart disease patients with lesions in three or more vessels than those with lesions in one or two vessels. Moreover, an elevated FFA level was identified as an independent risk factor for AMI on multivariate regression analysis and shown to be a sensitive and specific indicator for AMI diagnosis by receiver operating characteristic curve analysis. Conclusion: An elevated FFA level is an independent risk factor and independent diagnostic marker for AMI.

The Nutraceutical Value of Olive Oil and Its Bioactive Constituents on the Cardiovascular System. Focusing on Main Strategies to Slow Down Its Quality Decay during Production and Storage

Cardiovascular diseases represent the principal cause of morbidity and mortality worldwide. It is well-known that oxidative stress and inflammatory processes are strongly implicated in their pathogenesis; therefore, anti-oxidant and anti-inflammatory agents can represent effective tools. In recent years a large number of scientific reports have pointed out the nutraceutical and nutritional value of extra virgin olive oils (EVOO), strongholds of the Mediterranean diet, endowed with a high nutritional quality and defined as functional foods. In regard to EVOO, it is a food composed of a major saponifiable fraction, represented by oleic acid, and a minor unsaponifiable fraction, including a high number of vitamins, polyphenols, and squalene. Several reports suggest that the beneficial effects of EVOO are linked to the minor components, but recently, further studies have shed light on the health effects of the fatty fraction and the other constituents of the unsaponifiable fraction. In the first part of this review, an analysis of the clinical and preclinical evidence of the cardiovascular beneficial effects of each constituent is carried out. The second part of this review is dedicated to the main operating conditions during production and/or storage that can directly influence the shelf life of olive oil in terms of both nutraceutical properties and sensory quality.

Novel role of PKR in palmitate-induced Sirt1 inactivation and endothelial cell senescence

Endothelial cell senescence is regarded as a vital characteristic of cardiovascular diseases. Elevated palmitate (PA) is an independent risk factor of cardiovascular diseases, but its role in endothelial cell senescence is currently unknown. During the course of studying the prosenescent role of PA, we discovered a key role of dsRNA-dependent protein kinase [protein kinase R (PKR)] in endothelial senescence. Exposure of human umbilical vein endothelial cells (HUVECs) to PA-induced cell senescence is characterized by increased levels of senescence-associated β-galactose glucosidase activity, excessive production of reactive oxygen species production, impaired cellular proliferation, and G1 phase arrest. This phenomenon is associated with an increase of PKR autophosphorylation and decreased activity of sirtuin 1 (Sirt1), a pivotal antisenescent factor. PKR inactivation by PKR siRNA or its phosphorylation inhibitor 2-aminopurine significantly attenuated PA-induced HUVEC senescence by reversing Sirt1 activity and its downstream signaling. Moreover, to study the regulatory mechanism between PKR and Sirt1, we found that PKR promotes JNK activation to inhibit Sirt1 activity and that this effect could be reversed by the JNK inhibitor SP600125. These findings provide evidence that PKR mediates PA-induced HUVEC senescence by inhibiting Sirt1 signaling. Our study provides novel insights into the actions and mechanisms of PKR in endothelial senescence.

NEW & NOTEWORTHY This study first provides a novel observation that dsRNA-dependent protein kinase (PKR) mediates palmitate-induced sirtuin 1 inactivation and subsequent human umbilical vein endothelial cell senescence. Most importantly, these new findings will provide a potential therapeutic strategy to improve free fatty acid-induced endothelial senescence by targeting PKR in cardiovascular diseases.

A high concentration of fatty acids induces TNF-α as well as NO release mediated by the P2X4 receptor, and the protective effects of puerarin in RAW264.7 cells

Circulating levels of free fatty acids (FFAs) are often found to be increased in patients with type 2 diabetes mellitus (T2DM) and metabolic syndrome (MS). High plasma FFA levels may give rise to maladaptive macrophage activation and promote inflammatory responses, which has been proposed as a potential mechanism for the development of DM and MS. P2X4 receptor (P2X4R), a ligand-gated cation channel activated by extracellular adenosine triphosphate (ATP), plays a primary role in the regulation of inflammatory responses. Puerarin has been reported to possess potential anti-inflammatory activity. However, the anti-inflammatory activity of puerarin and the underlying molecular mechanisms in a setting of a high concentration of FFAs remain unknown. In this study, we found that a high concentration of FFAs increased the expression of P2X4R, cytosolic Ca²⁺ concentration and the phosphorylation of extracellular signal-regulated kinase (ERK) and induced the expression of tumor necrosis factor (TNF)-α and inducible nitric oxide synthase (iNOS) mRNA and the release of TNF-α and nitric oxide (NO) in RAW264.7 macrophages. Such a high concentration FFA-induced inflammation may be reversed by the P2X4R selective antagonist 5-BDBD, which manifests the important role of P2X4R in the TNF-α and NO release caused by the high concentration of FFAs in RAW264.7 cells. Molecular docking data showed that puerarin could interfere with the activation of P2X4R by forming hydrogen bonding towards residue Arg267, an important residue essential for the canonical activation of P2X4R. Treatment with puerarin dose-dependently reduced high concentration FFA-elevated P2X4R expression and inhibited P2X4R-mediated inflammatory signalling, including high concentration FFA-evoked [Ca²⁺]_i, ERK phosphorylation, expression of TNF-α and iNOS mRNA and release of TNF-α and NO. Our findings emphasize the critical role of P2X4R in high concentration FFA-induced TNF-α and NO release of RAW264.7 macrophages. Puerarin notably counteracts these high concentration FFA-induced adverse effects through its inhibition of P2X4R expression and P2X4R-mediated inflammatory signalling.

Adipose Triglyceride Lipase Gene Polymorphisms is Not Associated with Free Fatty Acid Levels in Chinese Han Population

BACKGROUND

Elevated levels of free fatty acids (FFAs) play a role in the pathogenesis of insulin resistance and atherosclerosis. Adipose triglyceride lipase (also defined as patatin-like phospholipase domain containing 2 or PNPLA2) has been demonstrated to contribute to the release of FFA. The aim of this study was to investigate the association of PNPLA2 gene variations with FFA levels in healthy Chinese Han population.

METHODS

Single-nucleotide polymorphisms of PNPLA2 were genotyped using TaqMan method to perform association studies with serum level of FFA and other lipid parameters in 1765 subjects among healthy Chinese Han population. All the subjects were divided into two groups: normal FFAs group (FFAs ≤0.88 mmol/L) and high FFAs group (FFAs >0.88 mmol/L).

RESULTS

Neither rs7925131 nor rs7942159 was significantly associated with FFA level. We observed no difference in the genotype frequency of rs7925131 or rs7942159 between the normal FFA group and the high FFA group.

CONCLUSIONS

Our results do not support an association of rs7925131 or rs7942159 with the FFA levels among the Chinese Han population.

Autophagy mediates free fatty acid effects on MDA-MB-231 cell proliferation, migration and invasion

Epidemiological and animal studies indicate an association between high levels of dietary fat intake and an increased risk of breast cancer. The multifaceted role of autophagy in cancer has been revealed in previous years. However, the mechanism of this role remains unknown. In the present study, the two most common free fatty acids, palmitate acid (PA) and oleic acid (OA), were used to determine the effect on human breast cancer MDA-MB-231 cells, and the possible role of autophagy was investigated by detecting light chain 3 (LC3)-II/I. Bafliomycin A1 was used to detect autophagy flux. High palmitate acid condition-induced MDA-MB-231 cell death and invasion were mitigated by 3-methyladenine pretreatment or transfection with shRNA against autophagy protein 5. By contrast, high oleic acid condition induced MDA-MB-231 cell proliferation, migration and invasion were mitigated using rapamycin. The present results suggest that autophagy has an important role in the effects of PA and OA on breast cancer growth and metastasis in vitro.

Conjugated fatty acid-rich oil from Gynostrmma pentaphyllum seed can ameliorate lipid and glucose metabolism in type 2 diabetes mellitus mice

Gynostrmma pentaphyllumseed oil (GPSO), extracted fromG. pentaphyllumseeds, is rich in conjugated linolenic acid, which is a special fatty acid consisting ofcis-9,trans-11,trans-13 isomers.

Cerebrospinal Fluid Free Fatty Acid Levels Are Associated with Stroke Subtypes and Severity in Chinese Patients with Acute Ischemic Stroke

OBJECTIVE

To assess the clinical significance of cerebrospinal fluid (CSF) free fatty acid (FFA) levels in Chinese patients with acute ischemic stroke.

METHODS

From December 2011 to October 2014, all patients with first-ever acute ischemic stroke were recruited to participate in the study. CSF levels of FFAs were assayed at 4 time points, and severity of stroke was evaluated with the National Institutes of Health Stroke Scale (NIHSS) score on admission.

RESULTS

Median CSF FFA levels were significantly (P < 0.0001) higher in patients with stroke compared with control subjects. CSF FFA levels reflected the disease severity of acute ischemic stroke. There were significant positive associations between CSF FFA levels and NIHSS scores (r = 0.424, P < 0.0001) and infarct volume (r = 0.289, P < 0.0001). CSF FFA levels in patients with cardioembolic (CE) stroke were significantly higher compared with patients with non-CE stroke (0.34 mmol/L [interquartile range, 0.26-0.42] vs. 0.14 mmol/L [interquartile range, 0.08-0.23]; P < 0.0001). Based on the receiver operating characteristic curve, the optimal cutoff value of CSF FFA levels as an indicator for the diagnosis of CE stroke was projected to be 0.22 mmol/L, which yielded a sensitivity of 83.3% and a specificity of 75.3%, and the area under the curve was 0.873 (95% confidence interval, 0.810-0.935).

CONCLUSIONS

CSF FFA levels at the time of admission were associated with stroke severity and lesion volumes. In addition, CE stroke can be distinguished from other stroke etiologies by measuring CSF FFA levels very early.