Phospholipase A1 Member A Activates Fibroblast-like Synoviocytes through the Autotaxin-Lysophosphatidic Acid Receptor Axis

The Role of Autotaxin and LPA Signaling in Embryonic Development, Pathophysiology and Cancer

Autotaxin (ATX) or Ectonucleotide Pyrophosphatase/Phosphodiesterase 2 (ENPP2) is a secreted enzyme with lysophospholipase D activity, with its primary function being the extracellular hydrolysis of lysophosphatidylcholine (LPC) to lysophosphatidic acid (LPA), a bioactive lipid [...].

The Age-Accompanied and Diet-Associated Remodeling of the Phospholipid, Amino Acid, and SCFA Metabolism of Healthy Centenarians from a Chinese Longevous Region: A Window into Exceptional Longevity

As centenarians provide a paradigm of healthy aging, investigating the comprehensive metabolic profiles of healthy centenarians is of utmost importance for the pursuit of health and longevity. However, relevant reports, especially studies considering the dietary influence on metabolism, are still limited, mostly lacking the guidance of a model of healthy aging. Therefore, exploring the signatures of the integrative metabolic profiles of the healthy centenarians from a famous longevous region, Bama County, China, should be an effective way. The global metabolome in urine and the short-chain fatty acids (SCFAs) in the feces of 30 healthy centenarians and 31 elderly people aged 60−70 from the longevous region were analyzed by non-targeted metabolomics combined with metabolic target analysis. The results showed that the characteristic metabolites related to longevity were mostly summarized into phosphatidylserine, lyso-phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol, bile acids, and amino acids (p < 0.05). Six metabolic pathways were found significant relevant to longevity. Furthermore, acetic acid, propionic acid, butyric acid, valeric acid, and total SCFA were significantly increased in the centenarian group (p < 0.05) and were also positively associated with the dietary fiber intake (p < 0.01). It was age-accompanied and diet-associated remodeling of phospholipid, amino acid, and SCFA metabolism that expressed the unique metabolic signatures related to exceptional longevity. This metabolic remodeling is suggestive of cognitive benefits, better antioxidant capacity, the attenuation of local inflammation, and health-span-promoting processes, which play a critical and positive role in shaping healthy aging.

The inflammasomes: crosstalk between innate immunity and hematology

BACKGROUND

The inflammasome is a cytosolic multi-protein complex responsible for the proteolytic maturation of pro-inflammatory cytokines IL-1ß and IL-18 and of gasdermin-D, which mediates membrane pore formation and the cytokines release, or eventually a lytic cell death known as pyroptosis. Inflammation has long been accepted as a key component of hematologic conditions, either oncological or benign diseases.

OBJECTIVES

This study aims to review the current knowledge about the contribution of inflammasome in hematologic diseases. We attempted to depict the participation of specific inflammasome receptors, and the possible cell-specific consequence of complex activation, as well as the use of anti-inflammasome therapies.

METHODS

We performed a keyword-based search in public databases (Pubmed.gov, ClinicalTrials.gov.).

CONCLUSION

Different blood cells variably express inflammasome components. Considering the immunosuppression associated with both the disease and the treatment of some hematologic diseases, and a microenvironment that allows neoplastic cell proliferation, inflammasomes could be a link between innate immunity and disease progression, as well as an interesting therapeutic target.

Phospholipase A1 Member A Deficiency Alleviates Mannan-Induced Psoriatic Arthritis in Mice Model

Synovial fluids from rheumatoid and psoriatic arthritis patients have high levels of PLA1A. The current study was to understand PLA1A functions in the pathophysiology of rheumatic diseases. We generated Pla1a−/− mice to assess their phenotype and the impact of PLA1A deficiency on the development of mannan-induced psoriatic arthritis (MIP). Mice were evaluated routinely for the induced symptoms. On the day of sacrifice, blood samples were collected for hematology analysis and prepared for plasma. Livers were collected. Lymph node immune cells were analyzed using flow cytometry. We performed μCT scans of hind paws from naïve and mannan-induced female mice. Cytokines/chemokines were quantified using Luminex in hind paw tissues and plasma of female mice. Pla1a−/− mice showed a slight increase in circulating and lymph node lymphocytes. CD4+ T cells contributed most to this increase in lymph nodes (p = 0.023). In the MIP model, the lymph node ratios of CD3+ to CD19+ and CD4+ to CD8+ were higher in Pla1a−/− mice. Pla1a−/− mice were less susceptible to MIP (p < 0.001) and showed reduced bone erosions. Pla1a−/− mice also showed reduced IL-17, KC, IP-10, MIP-1β, LIF, and VEGF in hind paw tissues as compared to WT mice (p < 0.05). These findings indicated that PLA1A deficiency protected from the development of the MIP disease. The data suggested that PLA1A could contribute to MIP through increased activation of lymphocytes, possibly those producing IL-17.