Effects of Long-Chain Fatty Acyl-CoA Synthetase 1 on Diglyceride Synthesis and Arachidonic Acid Metabolism in Sheep Adipocytes

Long-chain fatty acyl-CoA synthetase (ACSLs) is an essential enzyme for the synthesis of fatty acyl-CoA. ACSL1 plays a key role in the synthesis of triglycerides, phospholipids, and cholesterol esters.

BACKGROUND

In the current study, triglyceride content did not increase after overexpression of the ACSL1 gene.

METHODS

RNA-seq and lipid metabolome profiling were performed to determine why triglyceride levels did not change with ACSL1 overexpression.

RESULTS

Fatty acyl-CoA produced by ACSL1 was determined to be involved in the diglyceride synthesis pathway, and diglyceride content significantly increased when ACSL1 was overexpressed. Moreover, the arachidonic acid (AA) content in sheep adipocytes significantly increased, and the level of cyclooxygenase 2 (COX2) expression, the downstream metabolic gene, was significantly downregulated. Knocking down the ACSL1 gene was associated with an increase in COX2 mRNA expression, as well as an increase in prostaglandin content, which is the downstream metabolite of AA.

CONCLUSIONS

The overexpression of the ACSL1 gene promotes the production of AA via downregulation of COX2 gene expression.

Relationship Between the Gastrointestinal Side Effects of an Anti-Hypertensive Medication and Changes in the Serum Lipid Metabolome

An earlier study using a rat model system indicated that the active ingredients contained in the anti-hypertensive medication amlodipine (AMD) appeared to induce various bowel problems, including constipation and inflammation. A probiotic blend was found to alleviate intestinal complications caused by the medicine. To gain more extensive insight into the beneficial effects of the probiotic blend, we investigated the changes in metabolite levels using a non-targeted metabolic approach with ultra-performance liquid chromatography-quadrupole/time-of-fligh (UPLC-q/TOF) mass spectrometry. Analysis of lipid metabolites revealed that rats that received AMD had a different metabolome profile compared with control rats and rats that received AMD plus the probiotic blend. In the AMD-administered group, serum levels of phosphatidylcholines, lysophosphatidylcholines, sphingomyelins, triglycerides with large numbers of double bonds, cholesterols, sterol derivatives, and cholesterol esters (all p < 0.05) were increased compared with those of the control group and the group that received AMD plus the probiotic blend. The AMD-administered group also exhibited significantly decreased levels of triglycerides with small numbers of double bonds (all p < 0.05). These results support our hypothesis that AMD-induced compositional changes in the gut microbiota are a causal factor in inflammation.