Quercetin inhibits caspase-1-dependent macrophage pyroptosis in experimental folic acid nephropathy.

BACKGROUND: The role of pyroptosis in kidney disease is limited and incomplete. Quercetin, a flavonoid compound present in a variety of fruits, vegetables, and plants, has shown antioxidant and anti-inflammatory properties. This study was designed to validate the importance of pyroptosis in an experimental model of folic acid nephropathy and to explore the effect of quercetin in protecting against pyroptosis. METHODS: Gene set enrichment analysis (GSEA) and weighted gene co-expression network analysis (WGCNA) were used to establish the correlation between pyroptosis and folic acid nephropathy. Immune cell infiltration, network pharmacology and single-cell RNA sequencing analysis were utilized to ascertain the specific target of quercetin in relation to pyroptosis. Finally, quercetin's role was verified in vivo and in vitro. RESULTS: The GSEA analysis revealed a significant correlation between pyroptosis and folic acid nephropathy (NES = 1.764, P = 0.004). The hub genes identified through WGCNA were closely associated with inflammation. Molecular docking demonstrated a strong binding affinity between quercetin and caspase-1, a protein known to be involved in macrophage function, as confirmed by immune cell infiltration and single-cell analysis. Quercetin demonstrated a significant amelioration of kidney injury and reduction in macrophage infiltration in the animal model. Furthermore, quercetin exhibited a significant inhibition of caspase-1 expression, subsequently leading to the inhibition of pro-inflammatory cytokines expression, such as IL-1ß, IL-18, TNF-α, and IL-6. The inhibitory effect of quercetin on macrophage pyroptosis was also confirmed in RAW264.7 cells. CONCLUSION: This study contributes substantial evidence to support the significant role of pyroptosis in the development of folic acid nephropathy, and highlights the ability of quercetin to downregulate caspase-1 in macrophages as a protective mechanism against pyroptosis.

Quantifying the ecological carrying capacity of grasslands in Inner Mongolia.

Quantifying the ecological carrying capacity has emerged as a crucial factor for maintaining ecosystem stability for sustainable development in vulnerable eco-regions. Here, we propose a new framework for ecological carrying capacity quantification suitable for vulnerable eco-regions. We applied this framework to calculate the ecological carrying capacity of Inner Mongolia from 1987-2015 and used a geographical detector to identify the driving factors behind spatial heterogeneity. Our results revealed the following. (1) The above-ground net primary production (ANPP) required to support the ecosystem service of soil conservation (ANPPSC) decreased from northeast to southwest, whereas the distribution pattern of ANPP required to support the ecosystem service of sand fixation (ANPPSF) exhibited a contrary trend. The average annual ANPP required to support the ecosystem service of natural regeneration (ANPPNR) in Inner Mongolia from 1987 to 2015 was 101.27 gCm-2year-1, revealing a similar spatial distribution with ANPP. (2) The total ecological carrying capacity of Inner Mongolian grassland was 78.52 million sheep unit hm-2. The regions with insufficient provisioning service capability accounted for 4.18% of the total area, primarily concentrated in the east and northwest. (3) The average optimal livestock number for grasslands in Inner Mongolia was 1.59 sheep unit hm-2 from 1987-2015, ranging from 0.77 to 1.69 sheep unit hm-2 across different zones. The average ecological carrying capacity of the cold temperate humid, medium-temperate arid, and warm temperate semi-humid regions was less than 1.08 sheep unit m-2, suggesting a need to prohibit grazing in these areas. (4) The primary influencing factors affecting ecological carrying capacity distribution were normalized difference vegetation index (NDVI), precipitation, and soil type. The framework developed herein can help identify sustainable development potential from the ecosystem service perspective and effectively contribute to decision-making in grassland ecosystem management.

Risk of lower limb amputation in diabetic patients using SGLT2 inhibitors versus DPP4 inhibitors or GLP-1 agonists: a meta-analysis of 2 million patients.

Background: The objective of this review was to assess the risk of lower limb amputation (LLA) in type 2 diabetic patients based on the use of sodium-glucose cotransporter 2 inhibitors (SGLT2i) versus dipeptidyl peptidase 4 inhibitors (DPP4i) or glucagon-like peptide-1 receptor agonists (GLP1a). Methods: PubMed, CENTRAL, Scopus, Web of Science, and Embase were referenced for articles published up to 5 February 2023. All types of studies comparing the drugs for LLA risk and reporting hazard ratios (HR) were included. Results: Thirteen studies with 2,095,033 patients were included. Meta-analysis of eight studies comparing SGLT2i with Dipeptidyl peptidase inhibitors (DPPi) showed that there was no difference in the risk of LLA between the two drug groups (HR: 0.98 95% CI: 0.73, 1.31 I2 = 89%). The outcomes were unchanged on sensitivity analysis. Another pooled analysis of six studies found no significant difference in the risk of LLA between SGLT2i and GLP1a users (HR: 1.26; 95% CI: 0.99, 1.60; I2 = 69%). The exclusion of a single study showed an increased risk of LLA with SGLT2i (HR: 1.35; 95% CI: 1.14, 1.60; I2 = 14%). Conclusion: The current updated meta-analysis found no significant difference in the risk of LLA between SGLT2i and DPP4i users. A tendency of increased risk of LLA was noted with SGLT2i as compared to GLP1a. Further studies shall increase the robustness of current findings.

Risk of lower limb amputation with SGLT2 inhibitors in comparison with DPP4 inhibitors or GLP-1 agonists among diabetic patients Diabetic foot leading to lower limb amputation (LLA) is a common complication of diabetes mellitus (DM). We compared the risk of LLA in DM patients taking either sodium-glucose cotransporter 2 inhibitors (SGLT2i) or dipeptidyl peptidase 4 inhibitors (DPP4i) / glucagon-like peptide-1 receptor agonists (GLP1a). We searched the available literature for published studies comparing the risk of LLA with SGLT2i versus DPP4i or GLP1a. Individual study data were combined to generate a comprehensive result. We could find 13 studies with data from approximately 2 million patients. After combining the data, we noted no difference in the risk of LLA between patients using SGLT2i versus DPPi or GLP1a. Nevertheless, when data from a single study was removed from the combined analysis, we noted an increased risk of LLA with SGLT2i in comparison with GLP1a users. To conclude, our study, which is a comprehensive literature review, found that there is no difference in the risk of LLA between SGLT2i and DPP4i users. A tendency of increased risk of LLA was seen with SGLT2i as compared to GLP1a, which requires further research.

Identification and validation of biomarkers related to Th1 cell infiltration in neuropathic pain.

Neuropathic pain (NP) is a widespread chronic pain with a prevalence of 6.9-10% in the general population, severely affecting patients' physical and mental health. Accumulating evidence indicated that the immune environment is an essential factor causing NP. However, the mechanism is unclear. This study attempted to analyze NP-related immune infiltration patterns. We downloaded the expression profiles from the Gene Expression Omnibus (GEO) database. The novel method of single-sample gene set enrichment analysis (ssGSEA) algorithm and weighted gene co-expression network analysis (WGCNA) was applied to identify immune-related genes and verified in vitro and in vivo experiments. The spared nerve injury (SNI) group was closely related to type1 T helper cells (Th1 cells), and two key genes (Abca1 and Fyb) positively correlated with Th1 cell infiltration. At the single-cell level, Abca1 and Fyb were significantly expressed in macrophages. In addition, we verified that Abca1 could affect the function of macrophages. Finally, we hypothesized that Abca1 is involved in the infiltration of Th1 cells into dorsal root ganglion (DRG) tissues and induces NP via immunoinflammatory response. Hence, the present study aimed to elucidate the correlation between NP and neuroinflammation and identify a new therapeutic target for treating NP.

AFM negatively regulates the infiltration of monocytes to mediate sepsis-associated acute kidney injury.

Background: Sepsis is organ dysfunction due to the host's deleterious response to infection, and the kidneys are one of the organs damaged in common sepsis. Sepsis-associated acute kidney injury (SA-AKI) increases the mortality in patients with sepsis. Although a substantial volume of research has improved the prevention and treatment of the disease, SA-SKI is still a significant clinical concern. Purpose: Aimed to use weighted gene co-expression network analysis (WGCNA) and immunoinfiltration analysis to study SA-AKI-related diagnostic markers and potential therapeutic targets. Methods: Immunoinfiltration analysis was performed on SA-AKI expression datasets from the Gene Expression Synthesis (GEO) database. A weighted gene co-expression network analysis (WGCNA) analysis was performed on immune invasion scores as trait data, and modules associated with immune cells of interest were identified as hub modules. Screening hub geneset in the hub module using protein-protein interaction (PPI) network analysis. The hub gene was identified as a target by intersecting with significantly different genes screened by differential expression analysis and validated using two external datasets. Finally, the correlation between the target gene, SA-AKI, and immune cells was verified experimentally. Results: Green modules associated with monocytes were identified using WGCNA and immune infiltration analysis. Differential expression analysis and PPI network analysis identified two hub genes (AFM and GSTA1). Further validation using additional AKI datasets GSE30718 and GSE44925 showed that AFM was significantly downregulated in AKI samples and correlated with the development of AKI. The correlation analysis of hub genes and immune cells showed that AFM was significantly associated with monocyte infiltration and hence, selected as a critical gene. In addition, Gene single-enrichment analysis (GSEA) and PPI analyses results showed that AFM was significantly related to the occurrence and development of SA-AKI. Conclusions: AFM is inversely correlated with the recruitment of monocytes and the release of various inflammatory factors in the kidneys of AKI. AFM can be a potential biomarker and therapeutic target for monocyte infiltration in sepsis-related AKI.

The Effect of SLC2A3 Expression on Cisplatin Resistance of Colorectal Cancer Cells.

Background: To study the molecular mechanism of cisplatin chemotherapy resistance in colorectal cancer cells and to explore the effect of miRNA in regulating the expression of glucose transporter 3 (SLC2A3) and the proliferation and migration of colon cancer cells. Methods: All samples were obtained from the People's Hospital of Wuhai, Wuhai, China between June 2019 and June 2020. Real-time quantitative PCR (qRT-PCR) was carried out to check the expression of miR-103a in these cell lines. Western blotting and Luciferase reporter gene detection confirmed the regulation of the miR-103a/SLC2A3 axis. Western blotting detected the activation of SLC2A3, caspased-9 and -3. Results: The expression of SLC2A3 protein in colon cancer cell lines was significantly higher than that of normal colon cancer cells, while the expression of SLC2A3 miRNA showed no significant difference (P<0.05). Then, through clone formation analysis, SLC2A3 was closely related to the proliferation of human colon cancer cells. Functional recovery experiments showed that increasing the expression of miR-103a could reverse the abnormal proliferation caused by overexpression of SLC2A3. Conclusion: Overall, miR-103a can inhibit the proliferation of human colon cancer cells by targeting SLC2A3, and this result will provide a potential target for the treatment of colon cancer.

Glucagon-like peptide-1 attenuates liver injury in the rat diabetes model.

The aim of present study is to examine the effect of glucagon-like peptide-1(GLP-1) on diabetes-induced liver injury and explore detailed mechanisms of GLP-1 hepatoprotective effect. 150 male Sprague-Dawley rats were randomly assigned into three groups with equal number, including Sham group, diabetes group and GLP-1 intervention group. Diabetes rat model was performed with intraperitoneal injection of streptozotocin (STZ, 65mg/kg). Fasting blood-glucose of rat model was assessed at 72h after STZ injection to verify diabetes rat model. Rats in Sham group were normally fed. Rats in GLP-1 intervention group received 2 ng/kg GLP-1 intervention, at 2, 4, 6 and 8 weeks after intervention, TUNEL staining were performed to examine apoptosis of liver tissue. PCR and Western blot were performed to examine insulin, GLP-1R, autophagy-associated gene and HDAC-1. Compared with diabetes group, insulin expression of GLP-1 intervention group increased significantly (P<0.05). TUNEL staining at different time showed apoptosis levels of liver tissues were reduced gradually after GLP-1 intervention (P<0.05). Compared with diabetes groups, the expressions of BCL2 and GLP-1R were increased, while the levels of caspase3 and LC3 were reduced in GLP-1 intervention group (P<0.05). GLP-1 treatment decreased levels of phosphorylated AKT, phosphorylated ERK1/2, and HDAC6 in liver tissues (P<0.05). GLP-1 treatment alleviated diabetes-induced liver injury via regulating autophagy. The mechanism of GLP-1 hepatoprotective effect could be via GLP-1R-ERK1/2-HDAC6 signaling pathway.

ABC copolymer silicone surfactant templating for biomimetic silicification.

Using the ABC copolymer silicone surfactant polydimethylsiloxane (PDMS)-graft-(polyethylene oxide (PEO)-block-propylene oxide (PPO)) (PSEP, Scheme 1a) as a template and tetraethoxysilane (TEOS) as a silica source, silica particles with various structures and morphologies (i.e., disordered spherical micellar aggregation, two-dimensional p6mm mesostructure, asymmetric multi-layer non-equilibrium vesicles and symmetric monolayer vesicles) were synthesized by changing the synthesis temperature from 30 to 80 °C. Increasing the hydrophobicity of the surfactant by increasing the temperature resulted in an increase in the surfactant packing parameter g, which led to the mesophase transformation from micellar to cylinder and later to a lamellar structure. The good compatibility between the PDMS and the TEOS, the different natures of the hydrophobic PDMS and PPO segments, and the hydrolysis and condensation rates of TEOS enabled the variation of silicification structures. This novel silicone surfactant templating route and a new type of materials with highly ordered mesostructures and asymmetric morphologies provide a new insight into the molecular factors governing inorganic-organic mesophase and biosilicification for fabricating functionalized materials.