Phospholipase A2 products predict the hematopoietic support capacity of horse serum

Phospholipases and Reactive Oxygen Species Derived Lipid Biomarkers in Healthy and Diseased Humans and Animals - A Focus on Lysophosphatidylcholine

Phospholipids (PL) are converted into lipid biomarkers by the action of phospholipases and reactive oxygen species (ROS), which are activated or released under certain physiological and pathophysiological conditions. Therefore, the in vivo concentration of such lipid biomarkers [e.g., lysophospholipids (LPLs)] is altered in humans and animals under different conditions such as inflammation, stress, medication, and nutrition. LPLs are particularly interesting because they are known to possess pro- and anti-inflammatory properties and may be generated by two different pathways: either by the influence of phospholipase A₂ or by different reactive oxygen species that are generated in significant amounts under inflammatory conditions. Both lead to the cleavage of unsaturated acyl residues. This review provides a short summary of the mechanisms by which lipid biomarkers are generated under in vitro and in vivo conditions. The focus will be on lysophosphatidylcholine (LPC) because usually, this is the LPL species which occurs in the highest concentration and is, thus, easily detectable by chromatographic and spectroscopic methods. Finally, the effects of lipid biomarkers as signaling molecules and their roles in different human and animal pathologies such as infertility, cancer, atherosclerosis, and aging will be shortly discussed.

A comparative study on the lipidome of normal knee synovial fluid from humans and horses

The current limitations in evaluating synovial fluid (SF) components in health and disease and between species are due in part to the lack of data on normal SF, because of low availability of SF from healthy articular joints. Our study aimed to quantify species-dependent differences in phospholipid (PL) profiles of normal knee SF obtained from equine and human donors. Knee SF was obtained during autopsy by arthrocentesis from 15 and 13 joint-healthy human and equine donors, respectively. PL species extracted from SF were quantitated by mass spectrometry whereas ELISA determined apolipoprotein (Apo) B-100. Wilcoxon’s rank sum test with adjustment of scores for tied values was applied followed by Holm´s method to account for multiple testing. Six lipid classes with 89 PL species were quantified, namely phosphatidylcholine, lysophosphatidylcholine, sphingomyelin, phosphatidylethanolamine, plasmalogen, and ceramide. Importantly, equine SF contains about half of the PL content determined in human SF with some characteristic changes in PL composition. Nutritional habits, decreased apolipoprotein levels and altered enzymatic activities may have caused the observed different PL profiles. Our study provides comprehensive quantitative data on PL species levels in normal human and equine knee SF so that research in joint diseases and articular lubrication can be facilitated.

The protection of indolealkylamines from LPS-induced inflammation in zebrafish

ETHNOPHARMACOLOGICAL RELEVANCE

Toad skin came from Bufo bufo gargarizans Cantor and Bufo melanostictus Schneider. As the traditional Chinese medicine, it had the effect of clearing away heat and detoxification. In traditional applications, toad skin was often used for the treatment of cancer and inflammation. Total indolealkylamines (IAAs) from this medicine were proved the main compounds exert anti-inflammatory activity in our previous research.

AIM OF THE STUDY

In the present study, we aimed to investigate the potential mechanism of anti-inflammatory activity of IAAs on LPS induced zebrafish.

MATERIALS AND METHODS

LPS induced zebrafish was applicated as an in vivo inflammation model to clarify the structure-activity relationship of 4 major IAAs (N-methyl serotonin, bufotenine, dehydrobufotenine and bufothionine) from toad skin. Quantitative RT-PCR was applied to detect key cytokines and members of the MyD88-dependent signaling pathway. In addition, the targeted lipidomics was conducted to find out the potential biomarkers in the inflammatory zebrafish. Network pharmacology was used to unveil the main enzymes closely related to the target lipids.

RESULTS

Our results showed that the anti-inflammatory activity of free IAAs (N-methyl serotonin, bufotenine and dehydrobufotenine) was more potent than that of combined IAAs (bufothionine). RT-PCR demonstrated that 4 IAAs exerted antiendotoxin inflammatory effect via suppressing the TLR4/MyD88/NF-κB and TLR4/MyD88/MAPKs signaling pathway. A total of 33 possible inflammatory biomarkers, including 14 SM, 6 Cer, 11 PC and 2 GlcCer, triggered by LPS were screened out. The levels of most of candidates could be regulated toward a normal level by IAAs, especially in N-methyl serotonin and dehydrobufotenine groups. Enzymes especially LBP, PLA₂, CERK, SMPD and SGMS were found closely associated with the regulation of most lipid markers.

CONCLUSIONS

Overall, the mechanism underlying the anti-inflammatory activity of IAAs probably attributed to their capability to suppress NF-κB and MAPKs inflammatory pathway. Meanwhile, IAAs could also interfere the metabolism of SM, Cer and PC probably by regulating LBP, PLA₂, CERK, SMPD and SGMS.