Arachidonic acid (AA) is an ω-6 polyunsaturated fatty acid, which mainly exists in the cell membrane in the form of phospholipid. Three major enzymatic pathways including the cyclooxygenase (COX), lipoxygenase (LOX) and cytochrome P450 monooxygenase (CYP450) pathways are involved in AA metabolism leading to the generation of a variety of lipid mediators such as prostaglandins, leukotrienes, hydroxyeicosatetraenoic acids (HETEs) and epoxyeicoastrienoic acids (EETs). These bioactive AA metabolites play an important role in the regulation of many physiological processes including the maintenance of liver glucose and lipid homeostasis. As the central metabolic organ, the liver is essential in metabolism of carbohydrates, lipids and proteins, and its dysfunction is associated with the pathogenesis of many metabolic diseases such as type 2 diabetes mellitus, dyslipidemia and nonalcoholic fatty liver disease (NAFLD). This article aims to provide an overview of the enzymatic pathways of AA and discuss the role of AA-derived lipid mediators in the regulation of hepatic glucose and lipid metabolism and their associations with the pathogenesis of major metabolic disorders.
Arachidonic Acid/metabolism* ; Diabetes Mellitus, Type 2 ; Glucose/metabolism* ; Homeostasis ; Humans ; Lipid Metabolism ; Liver

Arachidonic Acid ; metabolism ; Cardiovascular System ; Cytochrome P-450 Enzyme System ; metabolism ; Humans

OBJECTIVE: To investigate and reveal the underlying mechanism of the effect of total saponins from Dioscoreae nipponica Makino (TSDN) on the arachidonic acid pathway in monosodium urate (MSU) crystal-induced M1-polarized macrophages. METHODS: M1 polarization of RAW264.7 cells were induced by 1 µ g/mL lipopolysaccharide (LPS). The methylthiazolyldiphenyl-tetrazolium bromide method was then used to screen the concentration of TSDN. MSU (500 µ g/mL) was used to induce the gouty arthritis model. Afterwards, 10 µ g/L TSDN and 8 µ mol/L celecoxib, which was used as a positive control, were added to the above LPS and MSU-induced cells for 24 h. The mRNA and protein expressions of cyclooxygenase (COX) 2, 5-lipoxygenase (5-LOX), microsomal prostaglandin E synthase derived eicosanoids (mPGES)-1, leukotriene B (LTB)4, cytochrome P450 (CYP) 4A, and prostaglandin E2 (PGE₂) were tested by real-time polymerase chain reaction and Western blotting, respectively. The enzyme-linked immunosorbent assay was used to test the contents of M1 markers, including inducible nitric oxid synthase (NOS) 2, CD80, and CD86. RESULTS: TSDN inhibited the proliferation of M1 macrophages and decreased both the mRNA and protein expressions of COX2, 5-LOX, CYP4A, LTB4, and PGE₂ (P<0.01) while increased the mRNA and protein expression of mPGES-1 (P<0.05 or P<0.01). TSDN could also significantly decrease the contents of NOS2, CD80, and CD86 (P<0.01). CONCLUSION TSDN has an anti-inflammation effect on gouty arthritis in an in vitro model by regulating arachidonic acid signaling pathway.
Uric Acid/metabolism* ; Arachidonic Acid/metabolism* ; Dioscorea ; Arthritis, Gouty ; Lipopolysaccharides ; Saponins/pharmacology* ; Macrophages ; Signal Transduction ; RNA, Messenger/metabolism*

Arachidonic acid, as an important polyunsaturated fatty acid, is identified as potential food additives or pharmaceuticals for their biological activities. In recent years, arachidonic acid production by Mortierella alpina is becoming a research highlight. The prophase relevant researches focused on the mutagenic breeding and fermentation optimization. With the depth of investigation, the advancement concerning pathway for the biosynthesis of arachidonic acid in Mortierella alpina has been made. In this review, we summarized the prophase work briefly. Mainly, we discussed the biosynthesis pathway of arachidonic acid, the key enzymes, the construction of transformation system and the genetic modification. In addition, the prospect of microorganism arachidonic acid production is put forward.
Arachidonic Acid ; biosynthesis ; Culture Media ; Culture Techniques ; methods ; Genetic Engineering ; methods ; Mortierella ; genetics ; metabolism

This study aims to investigate the efficacy and possible mechanism of Liuwei Dihuang Pills in the treatment of diminished ovarian reserve(DOR) by using proteomic techniques. Firstly, cyclophosphamide(60 mg·kg~(-1)) combined with busulfan(6 mg·kg~(-1)) was injected intraperitoneally to establish the mouse model of DOR. After drug injection, the mice were continuously observed and the success of modeling was evaluated by the disturbance of the estrous cycle. After successful modeling, the mice were administrated with the suspension of Liuwei Dihuang Pills by gavage for 28 days. At the end of the gavage, four female mice were selected and caged together with males at a ratio of 2∶1 for the determination of the pregnancy rate. Blood and ovary samples were collected from the remaining mice on the next day after the end of gavage. Hematoxylin-eosin(HE) staining and transmission electron microscopy(TEM) were then employed to observe the morphological and ultrastructural changes in the ovaries. The serum levels of hormones and oxidation indicators were measured by enzyme-linked immunosorbent assay. Quantitative proteomics techniques were used to compare the ovarian protein expression before and after modeling and before and after the intervention with Liuwei Dihuang Pills. The results showed that Liuwei Dihuang Pills regulated the estrous cycle of DOR mice, elevated the serum levels of hormones and anti-oxidation indicators, promoted follicle development, protected the mitochondrial morphology of ovarian granulosa cells, and increased the litter size and survival of DOR mice. Furthermore, Liuwei Dihuang Pills negatively regulated the expression of 12 differentially expressed proteins associated with DOR, which were mainly involved in lipid catabolism, inflammatory response, immune regulation, and coenzyme biosynthesis. These differentially expressed proteins were significantly enriched in sphingolipid metabolism, arachidonic acid metabolism, ribosomes, ferroptosis, and cGMP-PKG signaling pathway. In summary, the occurrence of DOR and the treatment of DOR with Liuwei Dihuang Pills are associated with multiple biological pathways, mainly including oxidative stress response, inflammatory response, and immune regulation. "Mitochondria-oxidative stress-apoptosis" is the key to the treatment of DOR by Liuwei Dihuang Pills. YY1 and CYP4F3 may be the key upstream targets that trigger mitochondrial dysfunction and ROS accumulation, and the metabolism of arachidonic acid is the main signaling pathway of drug action.
Female ; Male ; Pregnancy ; Animals ; Mice ; Arachidonic Acid ; Ovarian Reserve ; Proteomics ; Ovary ; Lipid Metabolism

During revascularization after ischemia, oxygen free radicals and cytotoxic enzymes are released and they have a role in pathogenesis of ischemia-reperfusion injury. Glucocorticoid decreases oxygen free radical formation by inhibition of arachidonic acid metabolism, and alpha-lipoic acid scavenges nitric oxide(NO) with inhibition of hydroxy radical formation. Author investigated the role of glucocorticoid and alpha-lipoic acid to decrease ischemia reperfusion injury in 24 anesthetized rats (normal saline-injected, n= 8; dexamethasone-injected, n=8; alpha-lipoic acid-injected, n= 8), subjecting a soleus muscle to 4 hours of tourniquet ischemia followed by 2 hours of reperfusion, and evaluated the concentration of NO, tissue edema, and neutrophil count of rat skeletal muscle as a indicator of tissue damage by ischemia- reperfusion injury. We obtained the results that glucocorticoid and alpha-lipoic acid treatment decreased the increase of NO concentration, tissue edema, and neutrophil count significantly. These results support that pretreatment with glucocorticoid or alpha-lipoic acid has a beneficial effect on the preventive management of ischemia-reperfusion injury.
Animals ; Arachidonic Acid ; Edema ; Free Radicals ; Ischemia ; Metabolism ; Muscle, Skeletal ; Neutrophils ; Oxygen ; Rats ; Reperfusion ; Reperfusion Injury* ; Thioctic Acid* ; Tourniquets

This study aims to clarify the effect of Jingfang Mixture on the treatment of chronic urticarial and its mechanism, and investigate the regulatory effect of chronic urticaria on the metabolic disorder of endogenous metabolites in the blood. The mice were randomly divided into normal group, model group, and Jingfang Mixture group, and modeling and administration continued for 21 d. The changes in endogenous small molecules in rat serum were determined by ultra-high performance liquid chromatography-electrospray ionization-Q Exactive-Orbitrap-mass spectrometry(UHPLC-ESI-QE-Orbitrap-MS) metabolomics technology. The change trend of endogenous metabolites in rat serum was analyzed to find potential biomarkers. The results showed that Jingfang Mixture regulate 16 biomarkers, mainly including taurine, glutamate, succinic acid, docosahexaenoic acid, and arachidonic acid. Metabolic pathway analysis was carried out by MetaboAnalyst, and P<0.01 was taken as the potential key metabolic pathway. Ten metabolic pathways were closely related to the treatment of chronic urticarial by Jingfang Mixture, mainly involved in the glutamate metabolism, taurine and hypotaurine metabolism, arginine and proline metabolism, arachidonic acid metabolism, tricarboxylic acid cycle, unsaturated fatty acid biosynthesis, glutathione metabolism, phenylalanine metabolism, alanine, aspartic acid, and glutamate metabolism, and butyric acid metabolism. Glutamate metabolism and butyric acid metabolism involved more metabolic pathways than others. Therefore, it was speculated that Jingfang Mixture had a balanced regulating effect on the related metabolic pathways which caused the serum disorder in the rats with urticaria, and tended to regulate the metabolic differential to the normal level in the rats with urticaria. This paper provides references for studying the mechanism of Jingfang Mixture from the perspective of endogenous metabolites and metabolic pathways in vivo. At the same time, the endogenous substances explored in this paper can be used as important biomarkers for the prevention of urticaria.
Rats ; Mice ; Animals ; Chronic Urticaria ; Arachidonic Acid ; Butyric Acid ; Metabolomics/methods* ; Chromatography, High Pressure Liquid/methods* ; Biomarkers/metabolism* ; Taurine ; Glutamates

Arachidonic acid (AA) in the cell membrane produces a variety of metabolites by different enzymatic pathways. These lipid metabolites, along with other mediators, play an important role in the inflammatory processes. Many of them can bind directly to the receptors on the sensory endings and initiate electrical impulses to be transmitted to the central nervous system, causing reflex responses. These bioactive AA metabolites may also alter the lung mechanics (mechanical environment of the sensory ending), and in turn, stimulate sensory afferents. In addition, some metabolites may sensitize the sensory endings and make them more responsive to other mechanical or chemical stimulation. These metabolites may also induce other mediators and modulators to cause physiological effects. Furthermore, some of them may attract inflammatory cells to produce a localized effect. In short, AA metabolites may come from different sources and act through multiple pathways to stimulate airway sensors. This brief review is intended to illustrate the underlying mechanisms and help elucidate the inflammatory process in the airways.
Animals ; Arachidonic Acid ; metabolism ; Humans ; Inflammation ; physiopathology ; Respiratory Physiological Phenomena ; Respiratory System ; metabolism ; Sensory Receptor Cells ; physiology ; Vagus Nerve ; physiology

We have checked levels of leukotriene(LT) C4, one of the arachidonic acid(AA) metabolites, in the lumbar, cisternal and ventricular cerebrospinal fluid(CSF) of 37 patients admitted with diagnosis of aneurysmal subarachnoid hemorrhage(SAH) and in lumbar CSF of 10 patients without aneurysmal SAH as the control group. We compared the levels of LTC4 in the CSF of the patients with aneurysmal SAH with those of the control group. We observed the changes of levels of LTC4 periodically after the onset of SAH. We devided the data of patients with aneurysmal SAH into 3 groups according to sampling days(respectively 1-4, 5-11, 12-24 days after SAH) and the clinical spasm group was compared with that of the non-spasm group. We also looked for the differences in the sampling sites and the correlation between the white blood cell counts and the levels of LTC4 in the CSF. The results of this study showed that the mean level of CSF LTC4(+/- standard deviation) of the SAH group was significantly higher than that of the control group(215.59+/-94.95 vs. 98.44+/-31.72pg/ml, respectively : P<0.001). The level of the CSF LTC4 progressively increased upto 7-8 days after SAH and decreased thereafter in the spasm group. The level of the CSF LTC4 of the spasm group was significantly higher than that of the non-spasm group(239.03+/-49.94 vs. 163.06+/-64.39pg/ml, respectively : P<0.05) in the first 4 days after SAH. There was no significant difference in the level of CSF LTC4 in the ventricular, cisternal, and lumbar CSF statistically(196.25+/-61.15 vs. 222.51+/-101.50 vs. 233.40+/-100.85pg/ml, respectively : P>0.05) even though we expected the level in the cisternal CSF to be higher than the lumbar CSF. There was no correlation between the white blood cell counts and the levels of LTC4 in the CSF(correlation coefficient=0.1240). From this study it is concluded that : 1) the AA metabolism via the lipoxygenase pathway is enhanced after SAH ; 2) the LTC4 may play a role in the pathogenesis of cerebral vasospasm, especially in the early days after SAH ; 3) the extraction of CSF via the external ventricular or cisternal drainage may decrease substances such as LTC4 which was thought to be vasoconstrictor material ; and 4) the granulocyte production of the LTC4 accounts for only a small part.
Aneurysm* ; Arachidonic Acid ; Cerebrospinal Fluid* ; Diagnosis ; Drainage ; Granulocytes ; Humans ; Leukocyte Count ; Leukotriene C4* ; Lipoxygenase ; Metabolism ; Spasm ; Subarachnoid Hemorrhage* ; Vasospasm, Intracranial

The study was purposed to investigate whether the cyclooxygenase inhibitors from some dietary vegetables can inhibit platelet aggregation function by the arachidonic acid (AA). The vegetable juice was mixed with platelet rich plasma (PRP), and asprin was used as positive control. The maximum ratio of platelet aggregation induced by AA was measured on the aggregometer; heme and cyclooxygenase-1 (COX(1)) or cyclooxygenase-2 (COX(2)) were added to test tubes containing COX reaction buffer, the mixture was vortex-mixed and exposed to aspirin or vegetable juice, followed by addition of AA and then hydrochloric acid (1 mol/L) was added to stop the COX reaction, followed by chemical reduction with stannous chloride solution. The concentration of COX inhibitors was detected by the enzyme immunoassay kit; vegetable juice (aspirin as positive control) was mixed with whole blood, which was followed by the addition of AA, and then the reaction was stopped by adding indomethacin, centrifuged, then the supernatant was collected, and the plasma thromboxane B(2) (TXB(2)) was measured by radioimmunoassay. The results showed that spinach juice, garlic bolt juice, blanched garlic leave juice and Chinese leek juice could inhibit by 80% human platelet aggregation induced by AA. 4 kinds of vegetables were all found a certain amount of cyclooxygenase inhibitors, which COX(1) and COX(2) inhibitor concentrations of spinach were higher than that of aspirin; 4 vegetable juice could significantly reduce the human plasma concentrations of TXB(2) induced by AA (p < 0.05). It is concluded that 4 kinds of raw vegetables containing cyclooxygenase inhibitors inhibit the production of TXA(2) and thus hinder platelet aggregation. Raw spinach, garlic bolt, blanched garlic and chinese leek inhibit significantly AA-induced human platelet aggregation in vitro. 4 kinds of vegetables may have a good potential perspective of anti-platelet aggregation therapy or prevention of thrombosis.
Adult ; Arachidonic Acid ; metabolism ; Blood Platelets ; drug effects ; Cyclooxygenase Inhibitors ; pharmacology ; Female ; Humans ; Male ; Platelet Aggregation ; drug effects ; Vegetables ; chemistry