Sex- and Age-Related Metabolic Characteristics of Serum Free Fatty Acids in Healthy Chinese Adults

Association between plasma long-chain polyunsaturated n-3 fatty acids concentrations and cognitive function: findings from NHANES III

Background

With increased life expectancy, cognitive decline has emerged as a prevalent neurodegenerative disorder.

Objective

This study aimed to examine the correlation between concentrations of Plasma long-chain n-3 polyunsaturated fatty acids (LCPUFAs) and cognitive performance in elderly Americans.

Methods

Data were analyzed from older adults enrolled in two NHANES cycles. Participants completed four cognitive assessments, including the Immediate Recall Test (IRT), Delayed Recall Test (DRT), Animal Fluency Test (AFT), and Digit Symbol Substitution Test (DSST). Linear regression and restricted cubic spline modeling examined associations between plasma LCPUFAs levels and cognitive test outcomes.

Results

The cohort included 610 adults aged 69 years on average, 300 (49.2%) males and 310 (50.8%) females. The median LCPUFAs concentration was 309.4 μmol/L, with an interquartile range of 244.7-418.9 μmol/L. In unadjusted and adjusted generalized linear regression model analyses, circulating LCPUFAs exhibited significant positive correlations with DRT performance. No relationships were detected among those with chronic conditions (chronic heart failure, stroke, diabetes). A significant association between LCPUFAs levels and DRT scores was evident in males but not females.

Conclusion

Plasma LCPUFAs concentrations were significantly associated with DRT performance in males free of chronic illnesses, including heart failure, stroke, and diabetes.

Serum Saturated Fatty Acids including Very Long-Chain Saturated Fatty Acids and Colorectal Cancer Risk among Chinese Population

The association between circulating saturated fatty acids (SFAs) including very long-chain SFAs (VLCSFAs) and colorectal cancer (CRC) risk has not been clearly established. To investigate the association between serum SFAs and CRC risk in Chinese population, 680 CRC cases and 680 sex and age-matched (5-year interval) controls were recruited in our study. Serum levels of SFAs were detected by gas chromatography. Unconditional logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association between serum SFAs and CRC risk. Results showed that total SFAs were positively associated with the risk of CRC (adjusted OR _{quartile 4 vs. 1} = 2.64, 95%CI: 1.47-4.74). However, VLCSFAs were inversely associated with CRC risk (adjusted OR _{quartile 4 vs. 1} = 0.51, 95%CI: 0.36-0.72). Specifically, lauric acid, myristic acid, palmitic acid, heptadecanoic acid, and arachidic acid were positively associated with CRC risk, while behenic acid and lignoceric acid were inversely associated with CRC risk. This study indicates that higher levels of total serum SFAs and lower levels of serum VLCSFAs were associated with an increased risk of CRC in Chinese population. To reduce the risk of CRC, we recommend reducing the intake of foods containing palmitic acid and heptadecanoic acid such as animal products and dairy products, and moderately increasing the intake of foods containing VLCSFAs such as peanuts and canola oil.

Potential of atmospheric pressure ionization sources for the analysis of free fatty acids in clinical and biological samples by gas chromatography-mass spectrometry

Because of the central role of fatty acids in biological systems, their accurate quantification is still important. However, the impact of the complex matrix of biologically and clinically relevant samples such as plasma, serum, or cells makes the analysis still challenging, especially, when free non-esterified fatty acids have to be quantified. Here we developed and characterized a novel GC–MS method using pentafluorobenzyl bromide as a derivatization agent and compared different ionization techniques such as atmospheric pressure chemical ionization (APCI), atmospheric pressure chemical photoionization (APPI), and negative ion chemical ionization (NICI). The GC-APCI-MS showed the lowest limits of detection from 30 to 300 nM for a broad range of fatty acids and a similar response for various fatty acids from a chain length of 10 to 20 carbon atoms. This allows the number of internal standards necessary for accurate quantification to be reduced. Moreover, the use of pentafluorobenzyl bromide allows the direct derivatization of free fatty acids making them accessible for GC–MS analysis without labor-intense sample pretreatment.

Prognostic significance of pretreatment serum free fatty acid in patients with diffuse large B-cell lymphoma in the rituximab era: a retrospective analysis

Background

Fatty acid metabolism is reportedly associated with various cancers. However, the role of pretreatment serum free fatty acid (FFA) levels in diffuse large B-cell lymphoma (DLBCL) prognosis is still unclear, and our study aimed to better elucidate its influence on clinical outcomes.

Methods

The medical records of 221 newly diagnosed DLBCL patients admitted to Fujian Medical University Union Hospital from January 2011 to December 2016 were analysed retrospectively. Receiver operating characteristic curve analysis was used to determine a cut-off value for pretreatment serum FFA levels for prognostic prediction in DLBCL patients. The relationship between pretreatment serum FFA levels and clinical and laboratory parameters was analysed. Univariate and multivariate analyses were used to assess prognostic factors for overall survival (OS) and progression-free survival (PFS).

Results

Newly diagnosed DLBCL patients with high pretreatment serum FFA levels (≥0.495 mmol/l) had more B symptoms, higher serum lactate dehydrogenase levels (> upper limit of normal), >1 extranodal site, and higher International Prognostic Index score (3–5) compared to those with low pretreatment serum FFA levels (<0.495 mmol/l). Higher serum FFA levels were independent prognostic factors for poor OS, but not PFS.

Conclusions

High pretreatment serum FFA levels are associated with lower survival in untreated DLBCL patients.