Free fatty acids and peripheral blood mononuclear cells (PBMC) are correlated with chronic inflammation in obesity

Abstract Obesity-related chronic inflammation is closely related to the ability of immune cells to adapt to the body’s needs, research has shown that excess FAs can further activate pro-inflammatory transcription factors in the nucleus by interacting with various receptors such as CD36 and TLR4, thereby affecting the inflammatory state of cells. However, how the profile of various fatty acids in the blood of obese individuals is associated with chronic inflammation remains unclear. Objective The biomarkers associated with obesity were identified from 40 fatty acids (FAs) in the blood, and analyze the relationship between the biomarkers and chronic inflammation. Furthermore, by analyzing the difference in the expression of CD36, TLR4 and NF-κB p65 in peripheral blood mononuclear cells (PBMC) between obese and standard weight people, understand that immunophenotype PBMC is associated with chronic inflammation. Methods This study is a cross-sectional study. Participants were recruited from the Yangzhou Lipan weight loss training camp from May 2020 to July 2020. The sample size was 52 individuals, including 25 in the normal weight group and 27 in the obesity group. Individuals with obesity and controls of normal weight were recruited to identify biomarkers associated with obesity from 40 fatty acids in the blood; correlation analysis was conducted between the screened potential biomarkers FAs and the chronic inflammation index hs-CRP to identify FA biomarkers associated with chronic inflammation. Changes in the fatty acid receptor CD36, inflammatory receptor TLR4, and inflammatory nuclear transcription factor NF-κB p65 in PBMC subsets were used to further test the relationship between fatty acids and the inflammatory state in individuals with obesity. Results 23 potential FA biomarkers for obesity were screened, eleven of the potential obesity biomarkers were also significantly related to hs-CRP. Compared to the control group, in monocytes the obesity group expressed higher TLR4, CD36, and NF-κB p65 in lymphocytes, the obesity group expressed higher TLR4 and CD36; and in granulocytes the obesity group expressed higher CD36. Conclusion Blood FAs are associated with obesity and are associated with chronic inflammation through increased CD36, TLR4, and NF-κB p65 in monocytes.