Peroxisome proliferator activated receptor-α (PPAR-α) is significantly expressed in various tissues such as the liver, kidney, myocardium, and skeletal muscle, which plays a central role in the development of various diseases by regulating key physiological processes such as energy homeostasis, redox balance, inflammatory response, and ferroptosis. As an important metabolic and excretory organ of the body, renal dysfunction can lead to water and electrolyte imbalance, toxin accumulation, and multiple system complications. The causes of kidney injury are complex and diverse, including acute injury factors (such as ischemia/reperfusion, nephrotoxic drugs, septic shock, and immune glomerulopathy), as well as chronic progressive causes [such as metabolic disease-related nephropathy, hypertensive nephropathy (HN)], and risk factors such as alcohol abuse, obesity, and aging. This review briefly describes the structure, function, and activity regulation mechanism of PPAR-α, systematically elucidates the molecular regulatory network of PPAR-α in the pathological process of kidney injury including acute kidney injury (AKI) such as renal ischemia/reperfusion injury (IRI), drug-induced AKI, sepsis-associated acute kidney injury (SA-AKI), glomerulonephritis, chronic kidney disease (CKD) such as diabetic nephropathy (DN), HN, and other kidney injury, and summarizes the mechanisms related to PPAR-α regulation of kidney injury, including regulation of metabolism, antioxidation, anti-inflammation, anti-fibrosis, and anti-ferroptosis. This review also evaluates PPAR-α's medical value as a novel therapeutic target, and aims to provide theoretical basis for the development of kidney protection strategies based on PPAR-α targeted intervention.
Humans ; PPAR alpha/metabolism* ; Acute Kidney Injury/therapy* ; Animals ; Kidney/metabolism*

Objective To investigate the protective effect of recombinant Schistosoma japonicum cystatin(rSj-Cys)against acute liver injury induced by lipopolysaccharide(LPS)and D-GalN in mice.Methods Adult male C57BL/6J mice with or without LPS/D-GaIN-induced acute liver injury were given intraperitoneal injections of rSj-Cys or PBS 30 min after modeling(n=18),and serum and liver tissues samples were collected from 8 mice in each group 6 h after modeling.The survival of the remaining 10 mice in each group within 24 h was observed.Serum levels of ALT,AST,TNF-α and IL-6 of the mice were measured,and liver pathologies was observed with HE staining.The hepatic expressions of macrophage marker CD68,Bax,Bcl-2 and endoplasmic reticulum stress(ERS)-related proteins were detected using immunohistochemistry or immunoblotting,and TUNEL staining was used to detect hepatocyte apoptosis.Results The survival rates of PBS-and rSj-Cys-treated mouse models of acute liver injury were 30%and 80%at 12 h and were 10%and 60%at 24 h after modeling,respectively;no death occurred in the two control groups within 24 h.The mouse models showed significantly increased serum levels of AST,ALT,IL-6 and TNF-α and serious liver pathologies with increased hepatic expressions of CD68 and Bax,lowered expression of Bcl-2,increased hepatocyte apoptosis,and up-regulated expressions of ERS-related signaling pathway proteins GRP78,CHOP and NF-κB p-p65.Treatment of the mouse models significantly lowered the levels of AST,ALT,IL-6 and TNF-α,alleviated liver pathologies,reduced hepatic expressions of CD68,Bax,GRP78,CHOP and NF-κB p-p65,and enhanced the expression of Bcl-2.In the normal control mice,rSj-Cys injection did not produce any significant changes in these parameters compared with PBS.Conclusion rSj-Cys alleviates LPS/D-GalN-induced acute liver injury in mice by suppressing ERS,attenuating inflammation and inhibiting hepatocyte apoptosis.

Objective To investigate the protective effect of recombinant Schistosoma japonicum cystatin(rSj-Cys)against acute liver injury induced by lipopolysaccharide(LPS)and D-GalN in mice.Methods Adult male C57BL/6J mice with or without LPS/D-GaIN-induced acute liver injury were given intraperitoneal injections of rSj-Cys or PBS 30 min after modeling(n=18),and serum and liver tissues samples were collected from 8 mice in each group 6 h after modeling.The survival of the remaining 10 mice in each group within 24 h was observed.Serum levels of ALT,AST,TNF-α and IL-6 of the mice were measured,and liver pathologies was observed with HE staining.The hepatic expressions of macrophage marker CD68,Bax,Bcl-2 and endoplasmic reticulum stress(ERS)-related proteins were detected using immunohistochemistry or immunoblotting,and TUNEL staining was used to detect hepatocyte apoptosis.Results The survival rates of PBS-and rSj-Cys-treated mouse models of acute liver injury were 30%and 80%at 12 h and were 10%and 60%at 24 h after modeling,respectively;no death occurred in the two control groups within 24 h.The mouse models showed significantly increased serum levels of AST,ALT,IL-6 and TNF-α and serious liver pathologies with increased hepatic expressions of CD68 and Bax,lowered expression of Bcl-2,increased hepatocyte apoptosis,and up-regulated expressions of ERS-related signaling pathway proteins GRP78,CHOP and NF-κB p-p65.Treatment of the mouse models significantly lowered the levels of AST,ALT,IL-6 and TNF-α,alleviated liver pathologies,reduced hepatic expressions of CD68,Bax,GRP78,CHOP and NF-κB p-p65,and enhanced the expression of Bcl-2.In the normal control mice,rSj-Cys injection did not produce any significant changes in these parameters compared with PBS.Conclusion rSj-Cys alleviates LPS/D-GalN-induced acute liver injury in mice by suppressing ERS,attenuating inflammation and inhibiting hepatocyte apoptosis.

The interaction of gut microbiota and its metabolites with the host not only plays an important role in maintaining gut homeostasis and host health, but also is a key link in responding to pathogen infections. A thorough understanding of the changes in gut microbiota and its metabolites during infection, as well as their role and mechanism in host defense against infection, is helpful to guide anti-infection treatment. This review focuses on the role of gut microbiota and their metabolites in host defense against bacterial, fungal, and viral infections, and reveals that they can exert anti-infection effects through resistance mechanisms (inducing antimicrobial substances, training immunity, inhibiting pathogen respiration, directly neutralizing pathogens, immune regulation) and tolerance mechanisms (altering energy metabolism patterns of microbiota, cell proliferation and tissue damage repair, maintaining physiological signal transduction in extraintestinal organs, inflammation regulation, maintaining the integrity of the intestinal barrier), and also summarizes measures to regulate gut microbiota against pathogen infections, in order to provide more ideas for novel anti-infection prevention and treatment strategies targeting gut microbiota and its metabolites.

Infection is a common medical problem at present. Different pathogens can lead to different infections. Severe infections can ultimately lead to sepsis, resulting in multiple organ dysfunction and the high mortality of patients. Therefore, studying the occurrence and development of severe infections is essential to improve the survival rate of patients. More and more studies have revealed the important role of connection between intestine and liver in infectious diseases. The maintenance of intestinal mechanical barrier and biological barrier function and the regulation of intestinal flora metabolites can reduce infectious liver injury. Bile acids are important metabolites in the liver, which can inhibit the progression of certain infectious intestinal injuries and promote intestinal damage caused by certain pathogens. In this article, the mechanism of action of the intestinal-liver axis in infection was reviewed to find a new target for the treatment of clinical infection.

Objective:To explore the effects of neutrophilic granule protein (NGP) on the expression of lipocalin 2 (LCN2) in inflammatory macrophages and its mechanism.Methods:NGP-high-expressed RAW264.7 cells (NGP/RAW cells) and negative control RAW264.7 cells (NC/RAW cells) were cultured in vitro. Primary peritoneal macrophages of NGP-high-expressed mice and wild-type C57BL/6 mice were extracted, then cultured in vitro. The cell inflammatory model was established by stimulating with 10 mg/L lipopolysaccharide (LPS, LPS group), and the phosphate buffer solution (PBS) control group was set up. Enzyme-linked immunosorbent assay (ELISA) was used to detect the level of LCN2 in different types of cells. The protein expression of phosphorylated signal transduction and activator of transcription 1 (p-STAT1) was detected with Western blotting. Other NGP/RAW cells and NC/RAW cells were treated with 10 mg/L LPS, 5 mg/L STAT1 pathway inhibitor (fludarabine)+10 mg/L LPS, respectively. The PBS control group was set up. ELISA was used to detect the level of LCN2. Results:In different types of cells, the levels of LCN2 were increased significantly after LPS stimulation in the LPS group as compared with those in the PBS control group, and peaked at 24 hours (μmol/L: 25.61±1.02 vs. 0.46±0.02 in NC/RAW cells, 74.51±2.14 vs. 0.25±0.04 in NGP/RAW cells, 10.13±0.22 vs. 0.01±0.01 in primary macrophages of wild-type C57BL/6 mice, 28.35±0.61 vs. 0.08±0.01 in primary macrophages of NGP-high-expressed mice, all P < 0.05), indicating that the expression of LCN2 in macrophages altered during inflammation reaction. The level of LCN2 in NGP/RAW cells was found significantly increased at different time points after LPS stimulation comparing with that in NC/RAW cells (μmol/L: 8.32±0.22 vs. 3.12±0.11 at 6 hours, 23.12±0.86 vs. 8.12±0.32 at 12 hours, 74.51±2.14 vs. 25.61±1.02 at 24 hours, all P < 0.05), along with the expression of p-STAT1 was significantly up-regulated. The level of LCN2 in the primary macrophages of NGP-high-expressed mice was also significantly increased at 24 hours after LPS stimulation comparing with that in the primary macrophages of wild-type C57BL/6 mice (μmol/L: 28.35±0.61 vs. 10.13±0.22, P < 0.05). However, after pretreated with STAT1 pathway inhibitors, the production of LCN2 in NGP/RAW cells was decreased significantly comparing with that in the LPS group (μmol/L: 6.81±0.19 vs. 22.54±0.58, P < 0.05). But the inhibitors had no significant effect on LCN2 production in NC/RAW cells showing no significant difference as compared with LPS group (μmol/L: 8.04±0.20 vs. 7.86±0.15, P > 0.05), indicating that NGP could up-regulate the expression of LCN2 in macrophages stimulated by LPS by promoting STAT1 activation. Conclusion:NGP could positively regulate LCN2 expression in inflammatory macrophages by activating STAT1 pathway.

The risk of patient infection inevitably increases with the use of more invasive operations in the intensive care unit(ICU),including endotracheal tubes,indwelling catheter,central venous catheter,etc.The preparation of antibacterial coatings is an effective way to solve such infections.Antibacterial coatings,such as silver nanoparticles coating,zinc oxide coating,methyl blue coating,antimicrobial peptides coating,and nano titanium dioxide(TiO2)coating,can effectively prevent the formation of biofilms on the surface of implant materials.As a photocatalyst,TiO2 has excellent photocatalytic and antibacterial activity,non-toxic and biocompatible properties,strong physical and chemical stability,and long-lasting antibacterial properties,which makes it high value for research.This review summarizes the bactericidal mechanism and clinical application of TiO2,offering valuable reference for clinical practice.

Sepsis is a syndrome of systemic inflammatory response in which the body′s response to infection is dysregulated, and is characterized by persistent infection, excessive inflammation and immunosuppression, etc. It often leads to organ dysfunction and can be life threatening, and also a common complication after trauma. The pathogenesis of post-traumatic sepsis is still unclear at present due to the complexity of its etiology, progression and prognosis. Multi-omics technology is a method to combine two or more single omics for comprehensive analysis, which can reveal the interaction network among the disease-associated molecules from multiple perspectives and aspects and is of great significance for the analysis of the pathogenesis of post-traumatic sepsis. To this end, the authors reviewed the research progress on the role of multi-omics technology in elucidating the pathogenesis of post-traumatic sepsis from the perspectives of genomics, transcriptomics, proteomics, metabolomics, single-cell transcriptomics and combination of multi-omics technologies, etc so as to provide a reference for the researches on post-traumatic sepsis.

Objective:To investigate the related genes, signaling pathways and possible mechanisms of malignant transformation of human papillomavirus type 16 (HPV-16) immortalized cervical epithelial cell line H8.Methods:The malignant transformed H8 cell model was constructed, and the changes of cell invasion ability and cell migration ability of H8 cells after malignant transformation were detected by Transwell assay, and the changes of clone formation ability of H8 cells after malignant transformation were detected by plate clone formation assay. Total RNA was extracted from malignant transformed H8 cells and H8 cells, and the two groups of cells were sequenced by transcriptome using Illumina novaseq 6000 sequencing platform, differentially expressed genes (DEGs) were identified and analyzed, and Gene Ontology (GO) function enrichment analysis, Kyoto Encyclopedia of genes and genomes (KEGG) pathway enrichment analysis and protein-protein interaction were performed.Results:The invasion ability, migration ability and clone formation ability of malignant transformed H8 cells significantly increased as compared to H8 cells. A total of 203 differentially expressed genes were identified in H8 cells before and after malignant transformation, of which 98 were up-regulated and 105 down-regulated. GO enrichment analysis showed that DEGs were mainly involved in biological processes such as cellular processes, biological regulation, and metabolic processes. KEGG pathway enrichment analysis showed that DEGs were mainly enriched in alanine, aspartate and glutamate metabolic pathway, glycine, serine and threonine metabolism pathway, p53 signaling pathway and TGF-β signaling pathway, PI3K-Akt signaling pathway. PPI analysis screened 10 hub genes including DDIT3, TRIB3 and ASNS.Conclusions:Compared with H8 cells, malignant transformed H8 cells have a large number of differentially expressed genes and pathways at the transcriptional level, which could further provide new ideas for the mechanism of malignant transformation and carcinogenesis as well as finding new targets for the prevention of malignant transformation.

Objective:To explore the expression pattern of aryl hydrocarbon receptor (AhR) in mice peritoneal macrophages (PMs) after major trauma and analyze the effects of enhanced AhR expression on the inflammatory cytokine level and bactericidal ability after trauma.Methods:The experimental study method was used. Forty 6-8-week-old male C57BL/6J mice (the same mouse age, sex, and strain below) were divided into control group, post trauma hour (PTH) 2 group, PTH 6 group, and PTH 12 group according to the random number table (the same grouping method below), with 10 mice in each group. Mice in the latter 3 groups were constructed as severe trauma model with fracture+blood loss, while mice in control group were left untreated. The primary PMs (the same cells below) were extracted from the mice in control group, PTH 2 group, PTH 6 group, and PTH 12 group when uninjured or at PTH 2, 6, and 12, respectively. Then the protein and mRNA expressions of AhR were detected by Western blotting and real-time fluorescence quantitative reverse transcription polymerase chain reaction, respectively, and the gene expressions of AhR signaling pathway related molecules were analyzed by transcriptome sequencing. Twenty mice were divided into control group and PTH 6 group, with 10 mice in each group, and the PMs were extracted. The level of ubiquitin of AhR was detected by immunoprecipitation. Twelve mice were divided into dimethyl sulfoxide (DMSO) alone group, PTH 6+DMSO group, MG-132 alone group, and PTH 6+MG-132 group, with 3 mice in each group. After the corresponding treatment, PMs were extracted, and the protein expression of AhR was detected by Western blotting. Twenty mice were constructed as PTH 6 model. Then, the PMs were extracted and divided into empty negative control adenovirus (Ad-NC) group and AhR overexpression adenovirus (Ad-AhR) group. The protein expression of AhR was detected by Western blotting at 36 h after some PMs were transfected with the corresponding adenovirus. The rest cells in Ad-NC group were divided into Ad-NC alone group and Ad-NC+endotoxin/lipopolysaccharide (LPS) group, and the rest cells in Ad-AhR group were divided into Ad-AhR alone group and Ad-AhR+LPS group. The expressions of interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α) in the cell supernatant were detected by enzyme-linked immunosorbent assay at 12 h after the corresponding treatment ( n=6). Twenty mice were obtained to extract PMs. The cells were divided into control+Ad-NC group, PTH 6+Ad-NC group, control+Ad-AhR group, and PTH 6+Ad-AhR group, and the intracellular bacterial load was detected by plate spread method after the corresponding treatment ( n=6). Data were statistically analyzed with one-way analysis of variance, least significant difference test, analysis of variance for factorial design, and independent sample t test. Results:Compared with 1.16±0.28 of control group, the protein expressions of AhR in PMs in PTH 2 group (0.59±0.14), PTH 6 group (0.72±0.16), and PTH 12 group (0.71±0.17) were all significantly decreased ( P<0.05). The overall comparison of the difference of AhR mRNA expression in PMs among control group, PTH 2 group, PTH 6 group, and PTH 12 group showed no statistical significance ( P>0.05). The AhR signaling pathway related molecules included AhR, AhR inhibitor, cytochrome P450 family member 1b1, cytochrome P450 family member 11a1, heat shock protein 90, aryl hydrocarbon receptor-interaction protein, and heat shock protein 70 interaction protein. The heat shock protein 90 expression of PMs in PTH 2 group was higher than that in control group, while the expressions of other molecules did not change significantly after trauma. Compared with that in control group, the level of ubiquitin of AhR in PMs in PTH 6 group was increased. Compared with that in DMSO alone group, the protein expression of AhR in PMs in PTH 6+DMSO group was decreased, while that in PMs in MG-132 alone group had no significant change. Compared with that in PTH 6+DMSO group, the protein expression of AhR in PMs in PTH 6+MG-132 group was up-regulated. At transfection hour 36, compared with that in Ad-NC group, the protein expression of AhR in PMs in Ad-AhR group was increased. At treatment hour 12, compared with those in Ad-NC+LPS group, the expressions of IL-6 and TNF-α in PM supernatant of Ad-AhR+LPS group were significantly decreased (with t values of 4.80 and 3.82, respectively, P<0.05). The number of intracellular bacteria of 1×10 6 PMs in control+Ad-NC group, PTH 6+Ad-NC group, control+Ad-AhR group, and PTH 6+Ad-AhR group was (3.0±1.8), (41.8±10.2), (1.8±1.2), and (24.2±6.3) colony forming unit, respectively. Compared with that in PTH 6+Ad-NC group, the number of intracellular bacteria of PMs in PTH 6+Ad-AhR group was significantly decreased ( t=3.61, P<0.05). Conclusions:Ubiquitin degradation of AhR in PMs of mice after major trauma results in decreased protein expression of AhR. Increasing the expression of AhR in post-traumatic macrophages can reduce the expressions of LPS-induced inflammatory cytokines IL-6 and TNF-α, and improve the bactericidal ability of macrophages after trauma.