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 explore the indexes affecting the prognosis of the ICU patients with sepsis,establish the nomogram model for prediction of 28-day mortality rate,and validate it.METHODS On the basis of criteria for diagnosis of sepsis(3.0 version),the related data of the sepsis patients were extracted from Medical Information Mart for Intensive Care-Ⅳ(MIMIC-Ⅳ)database for retrospective study and were randomly divided into the train-ing set and the validation set in a 7∶3 ratio.Univariate analysis and multivariate Cox proportional risk regression analysis were performed for the screening of influencing factors for prediction of 28-day mortality of the sepsis pa-tients.The nomogram prediction model was established based on the screened factors and was validated by the val-idation set,and the effect was evaluated.RESULTS A total of 7 955 sepsis patients were included.Seven variables were selected to establish the nomogram model for prediction of the 28-day mortality rate.The nomogram showed favorable performance in identification between the two cohorts,the area under receiver operating characteristic curves(AUROCs)were 0.748 and 0.721,respectively.Calibration curves and Hosmer-Lemeshow test(x2=8.689,10.614;P=0.369,0.225)indicated that the model had remarkable effect on correction.With the per-formance of decision curve analysis(DCA)and clinical impact curve(CIC),the model was considered to have high clinical application value.CONCLUSIONS The nomogram model shows favorable performance in prediction of the 28-day mortality rate and calibration capability.It is worthy to be further promoted and applied.

Objective:To analyze serum inflammatory factors associated with antihistamine resistance in patients with chronic spontaneous urticaria (CSU) .Methods:A total of 88 CSU patients were enrolled from Guangzhou Dermatology Hospital from January 2022 to December 2024. All patients received antihistamine treatment according to the "Guideline for diagnosis and treatment of urticaria in China (2022) " . Based on the 7-day urticaria activity score (UAS7) after 4-week treatment, these patients were divided into an antihistamine-sensitive group and an antihistamine-resistant group. Serum levels of inflammatory factors at the initial visit were analyzed using the Olink-targeted proteomics technology. Specific biomarkers associated with antihistamine resistance were identified, and Spearman correlation analysis was carried out to analyze correlations among differentially expressed proteins. A logistic regression model was constructed based on the Olink proteomics data, and the predictive performance of the model was evaluated using receiver operating characteristic (ROC) curve analysis. Measurement data were expressed as mean ± standard deviation or median (lower quartile, upper quartile) .Results:The 88 CSU patients aged 12 to 81 (38.78 ± 13.89) years, with the disease duration being 18 (7.00, 60.00) months. There were 32 patients in the antihistamine-sensitive group and 56 in the antihistamine-resistant group. No significant differences were found between the two groups in terms of age, disease duration, gender, or history of allergic diseases (all P > 0.05) . After 4 weeks of antihistamine treatment, the UAS7 score was significantly higher in the antihistamine-resistant group (25.00 [15.25, 31.00] points) than in the antihistamine-sensitive group (0.50 [0.00, 4.00] points; Z = -7.08, P < 0.001) . The Olink-targeted proteomics identified 5 differentially expressed proteins between the two groups: compared with the antihistamine-sensitive group, the antihistamine-resistant group showed > 2-fold higher expression of fibroblast growth factor 19 (FGF19) , interleukin-15 receptor subunit alpha (IL-15RA) , eotaxin (CCL11) , and monocyte chemoattractant protein-1 (MCP-1) ; in contrast, the expression of sulfotransferase 1A1 (ST1A1) in the antihistamine-sensitive group was 2.54 times that in the antihistamine-resistant group. Among the differentially expressed proteins, MCP-1 showed the highest specificity (1.00) for predicting antihistamine resistance, followed by CCL11 (0.97) . Correlation analysis revealed a significant positive correlation between MCP-1 and CCL11, and a significant negative correlation between IL-15RA and ST1A1. ROC curve analysis showed that MCP-1 and CCL11 had area under the curve values of 0.603 and 0.630, respectively, in predicting antihistamine resistance. Conclusion:MCP-1 and CCL11 may be potential biomarkers for predicting antihistamine resistance in CSU patients.

OBJECTIVE To explore the indexes affecting the prognosis of the ICU patients with sepsis,establish the nomogram model for prediction of 28-day mortality rate,and validate it.METHODS On the basis of criteria for diagnosis of sepsis(3.0 version),the related data of the sepsis patients were extracted from Medical Information Mart for Intensive Care-Ⅳ(MIMIC-Ⅳ)database for retrospective study and were randomly divided into the train-ing set and the validation set in a 7∶3 ratio.Univariate analysis and multivariate Cox proportional risk regression analysis were performed for the screening of influencing factors for prediction of 28-day mortality of the sepsis pa-tients.The nomogram prediction model was established based on the screened factors and was validated by the val-idation set,and the effect was evaluated.RESULTS A total of 7 955 sepsis patients were included.Seven variables were selected to establish the nomogram model for prediction of the 28-day mortality rate.The nomogram showed favorable performance in identification between the two cohorts,the area under receiver operating characteristic curves(AUROCs)were 0.748 and 0.721,respectively.Calibration curves and Hosmer-Lemeshow test(x2=8.689,10.614;P=0.369,0.225)indicated that the model had remarkable effect on correction.With the per-formance of decision curve analysis(DCA)and clinical impact curve(CIC),the model was considered to have high clinical application value.CONCLUSIONS The nomogram model shows favorable performance in prediction of the 28-day mortality rate and calibration capability.It is worthy to be further promoted and applied.

Objective:To analyze serum inflammatory factors associated with antihistamine resistance in patients with chronic spontaneous urticaria (CSU) .Methods:A total of 88 CSU patients were enrolled from Guangzhou Dermatology Hospital from January 2022 to December 2024. All patients received antihistamine treatment according to the "Guideline for diagnosis and treatment of urticaria in China (2022) " . Based on the 7-day urticaria activity score (UAS7) after 4-week treatment, these patients were divided into an antihistamine-sensitive group and an antihistamine-resistant group. Serum levels of inflammatory factors at the initial visit were analyzed using the Olink-targeted proteomics technology. Specific biomarkers associated with antihistamine resistance were identified, and Spearman correlation analysis was carried out to analyze correlations among differentially expressed proteins. A logistic regression model was constructed based on the Olink proteomics data, and the predictive performance of the model was evaluated using receiver operating characteristic (ROC) curve analysis. Measurement data were expressed as mean ± standard deviation or median (lower quartile, upper quartile) .Results:The 88 CSU patients aged 12 to 81 (38.78 ± 13.89) years, with the disease duration being 18 (7.00, 60.00) months. There were 32 patients in the antihistamine-sensitive group and 56 in the antihistamine-resistant group. No significant differences were found between the two groups in terms of age, disease duration, gender, or history of allergic diseases (all P > 0.05) . After 4 weeks of antihistamine treatment, the UAS7 score was significantly higher in the antihistamine-resistant group (25.00 [15.25, 31.00] points) than in the antihistamine-sensitive group (0.50 [0.00, 4.00] points; Z = -7.08, P < 0.001) . The Olink-targeted proteomics identified 5 differentially expressed proteins between the two groups: compared with the antihistamine-sensitive group, the antihistamine-resistant group showed > 2-fold higher expression of fibroblast growth factor 19 (FGF19) , interleukin-15 receptor subunit alpha (IL-15RA) , eotaxin (CCL11) , and monocyte chemoattractant protein-1 (MCP-1) ; in contrast, the expression of sulfotransferase 1A1 (ST1A1) in the antihistamine-sensitive group was 2.54 times that in the antihistamine-resistant group. Among the differentially expressed proteins, MCP-1 showed the highest specificity (1.00) for predicting antihistamine resistance, followed by CCL11 (0.97) . Correlation analysis revealed a significant positive correlation between MCP-1 and CCL11, and a significant negative correlation between IL-15RA and ST1A1. ROC curve analysis showed that MCP-1 and CCL11 had area under the curve values of 0.603 and 0.630, respectively, in predicting antihistamine resistance. Conclusion:MCP-1 and CCL11 may be potential biomarkers for predicting antihistamine resistance in CSU patients.

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.

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.

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.