GPR174 mRNA Acts as a Novel Prognostic Biomarker for Patients With Sepsis via Regulating the Inflammatory Response

Lysophosphatidylserine: A Signaling Lipid with Implications in Human Diseases

Lysophosphatidylserine (lyso-PS) has emerged as yet another important signaling lysophospholipid in mammals, and deregulation in its metabolism has been directly linked to an array of human autoimmune and neurological disorders. It has an indispensable role in several biological processes in humans, and therefore, cellular concentrations of lyso-PS are tightly regulated to ensure optimal signaling and functioning in physiological settings. Given its biological importance, the past two decades have seen an explosion in the available literature toward our understanding of diverse aspects of lyso-PS metabolism and signaling and its association with human diseases. In this Review, we aim to comprehensively summarize different aspects of lyso-PS, such as its structure, biodistribution, chemical synthesis, and SAR studies with some synthetic analogs. From a biochemical perspective, we provide an exhaustive coverage of the diverse biological activities modulated by lyso-PSs, such as its metabolism and the receptors that respond to them in humans. We also briefly discuss the human diseases associated with aberrant lyso-PS metabolism and signaling and posit some future directions that may advance our understanding of lyso-PS-mediated mammalian physiology.

Tocilizumab attenuates acute lung injury in rats with sepsis by regulating S100A12/NLRP3

OBJECTIVE

To investigate the mechanism of Tocilizumab (TCZ) in attenuating acute lung injury in rats with sepsis by regulating the S100A12/NLRP3 axis.

METHODS

A rat model of sepsis was constructed using cecal ligation and puncture (CLP). Rats were treated with TCZ, and their lung tissue was collected. H&E staining was used to detect pathologic damage to lung tissue, and lung wet/dry (W/D) weight ratio was measured to assess pulmonary edema. Lipid oxidation assay and superoxide dismutase (SOD) activity assay kits were used to measure malondialdehyde (MDA) and SOD levels. Primary rat pulmonary microvascular endothelial cells (MPVECs) were treated with lipopolysaccharide (LPS) to construct a rat model of sepsis, which was then treated with TCZ. The mRNA and protein expressions of S100A12/NLRP3 were detected by qRT-PCR and western blot, respectively. S100A12 knockdown and overexpression plasmids, and NLRP3 knockdown plasmids were constructed and transfected into sepsis cells to intervene in the levels of S100A12/NLRP3. The apoptosis rate was detected by apoptosis assay. The levels of IL-6, TNF-α, and IL-10 in cells and tissues were analyzed by ELISA.

RESULTS

Compared to the Sham group, the CLP group had increased W/D weight ratio of lung tissue, IL-6, TNF-α, and MDA levels, lowered IL-10 and SOD levels, and more severe tissue damage (all P<0.05). After TCZ treatment, the above indicators were improved. The expressions of S100A12/NLRP3 cells were increased in LPS-induced MPVECs, but decreased after TCZ treatment. LPS induced apoptosis, but TCZ reduced the apoptosis, weakened the secretion levels of IL-6 and TNF-α, and enhanced IL-10 secretion levels. Transfection to cause the overexpression of S100A12 or NLRP3 plasmid partially counteracted the effect of TCZ. Knockdown of S100A12 was transfected on the basis of overexpression of NLRP3, which weakened the countervailing effect of overexpressed NLRP3 on TCZ.

CONCLUSION

TCZ has a therapeutic effect on lung injury in rats with sepsis by reducing the expressions of S100A12/NLRP3.

Diagnoses Based on C-Reactive Protein Point-of-Care Tests

C-reactive protein (CRP) is an important part of the immune system's reaction to various pathological impulses such as bacterial infections, systemic inflammation, and internal organ failures. An increased CRP level serves to diagnose the mentioned pathological states. Both standard laboratory methods and simple point-of-care devices such as lateral flow tests and immunoturbidimetric assays serve for the instrumental diagnoses based on CRP. The current method for CRP has many flaws and limitations in its use. Biosensor and bioassay analytical devices are presently researched by many teams to provide more sensitive and better-suited tools for point-of-care tests of CRP in biological samples when compared to the standard methods. This review article is focused on mapping the diagnostical relevance of CRP, the applicability of the current analytical methods, and the recent innovations in the measurement of CRP level.