Ferroptosis-Related Genes in IgA Nephropathy: Screening for Potential Targets of the Mechanism.

Aims: Exploring key genes and potential molecular pathways of ferroptosis in immunoglobulin A nephropathy (IgAN). Methods: The IgAN datasets and ferroptosis-related genes (FRGs) were obtained in the Gene Expression Omnibus (GEO) and FerrDb database. Differentially expressed genes (DEGs) were identified using R software and intersected with FRGs to obtain differentially expressed FRGs (DE-FRGs). After that, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis (PEA) and Gene Ontology (GO) functional annotation were performed on DE-FRGs. In the Search Tool for the Retrieval of Interacting Genes (STRING) website, we construct a protein-protein interaction (PPI) network. The PPI network was further investigated with screening hub genes with Cytoscape software. The core genes were then subjected to gene set enrichment analysis (GSEA). Finally, the samples were analyzed for immune infiltration in R, and the correlation between hub genes and immune cells was analyzed. Results: A total of 347 DEGs were identified. CD44, CDO1, CYBB, IL1B, RRM2, AKR1C1, activated transcription factor-3 (ATF3), CDKN1A, GDF15, JUN, MGST1, MIOX, MT1G, NR4A1, PDK4, TNFAIP3, and ZFP36 were determined as DE-FRGs. JUN, IL1B, and ATF3 were then screened as hub genes. GSEA and immune infiltration analysis revealed that the hub genes were closely associated with immune inflammatory responses such as NOD-like receptor signaling, IL-17 signaling, and TNF signaling. Conclusions: Our results show that JUN and ATF3 are possibly critical genes in the process of IgAN ferroptosis and may be related with immune cell infiltration.

Therapeutic effects of traditional Chinese medicine on gouty nephropathy: Based on NF-κB signalingpathways.

As the final product of purine metabolism, excess serum uric acid (SUA) aggravates the process of some metabolic diseases. SUA causes renal tubule damage, interstitial fibrosis, and glomerular hardening, leading to gouty nephropathy (GN). A growing number of investigations have shown that NF-κB mediated inflammation and oxidative stress have been directly involved in the pathogenesis of GN. Traditional Chinese medicine's treatment methods of GN have amassed a wealth of treatment experience. In this review, we first describe the mechanism of NF-κB signaling pathways in GN. Subsequently, we highlight traditional Chinese medicine that can treat GN through NF-κB pathways. Finally, commenting on promising candidate targets of herbal medicine for GN treatment via suppressing NF-κB signaling pathways was summarized.

Chinese herbal medicine and its active compounds in attenuating renal injury via regulating autophagy in diabetic kidney disease.

Diabetic kidney disease (DKD) is the main cause of end-stage renal disease worldwide, and there is a lack of effective treatment strategies. Autophagy is a highly conserved lysosomal degradation process that maintains homeostasis and energy balance by removing protein aggregates and damaged organelles. Increasing evidence suggests that dysregulated autophagy may contribute to glomerular and tubulointerstitial lesions in the kidney under diabetic conditions. Emerging studies have shown that Chinese herbal medicine and its active compounds may ameliorate diabetic kidney injury by regulating autophagy. In this review, we summarize that dysregulation or insufficiency of autophagy in renal cells, including podocytes, glomerular mesangial cells, and proximal tubular epithelial cells, is a key mechanism for the development of DKD, and focus on the protective effects of Chinese herbal medicine and its active compounds. Moreover, we systematically reviewed the mechanism of autophagy in DKD regulated by Chinese herb compound preparations, single herb and active compounds, so as to provide new drug candidates for clinical treatment of DKD. Finally, we also reviewed the candidate targets of Chinese herbal medicine regulating autophagy for DKD. Therefore, further research on Chinese herbal medicine with autophagy regulation and their targets is of great significance for the realization of new targeted therapies for DKD.

Mechanism of dioscin ameliorating renal fibrosis through NF­κB signaling pathway­mediated inflammatory response.

Dioscin (DIS) is a natural compound derived from Chinese herbal medicine. In recent years, multiple studies have reported that DIS has immunoregulation, anti­fibrosis, anti­inflammation, anti­viral and anti­tumor effects. However, the mechanism by which DIS ameliorates renal fibrosis and inflammation remains to be elucidated. The aim of the present study was to investigate the role of DIS in renal fibrosis and inflammation and to explore its underlying mechanism. It used network pharmacology to predict the targets of DIS for the treatment of renal interstitial fibrosis. The present study was performed using unilateral ureteral obstruction mice and HK­2 cells in vivo and in vitro. The mice were treated with different doses of DIS. Kidney tissues were collected for histopathology staining, western blotting, immunohistochemistry staining and reverse transcription­quantitative (RT­q) PCR. TGF­ß1 (2 ng/ml) was used to induce renal fibrosis in the cells. Then, cells were respectively treated with DIS (3.125, 6.25, 12.5 µM) and Bay11­7082 (an inhibitor of NF­κB p65 nuclear transcription, 1 µM) for another 24 h. The expressions of inflammatory factors and NF­κB pathway proteins were detected by immunofluorescence, ELISA, western blotting and RT­qPCR. DIS alleviated renal injury in the UUO mice. Mechanistically, DIS not only decreased the expressions of inflammatory factors including IL­1ß, NOD­like receptor thermal protein domain associated protein 3, monocyte chemotactic protein 1, IL­6, TNF­α and IL­18 but also reduced the level of phosphorylation of NF­κB p65 in vivo and in vitro, which was similar to the impact of Bay11­7082. DIS ameliorated renal fibrosis by inhibiting the NF­κB signaling pathway­mediated inflammatory response, which may be a therapeutic pathway for delaying chronic kidney disease.

Gastrointestinal Absorption and Metabolic Dynamics of Jujuboside A, A Saponin Derived from the Seed of Ziziphus jujuba.

Jujuboside A (JuA), an active saponin, is responsible for the anxiolytic and sedative effects of Zizyphi Spinosae Semen (ZSS). In this study, the gastrointestinal absorption and metabolic dynamics of JuA were investigated in vivo and in vitro. The results showed that the bioavailability was 1.32% in rats, indicating only a trace amount of JuA was able to be absorbed. Further investigation revealed that its poor bioavailability was not caused by malabsorption but by the metabolic process. JuA was hydrolyzed largely in the stomach before being absorbed into the different parts of the intestine (especially duodenum and colon), and the gastric environment played a vital role in this process. Furthermore, the metabolites, jujuboside B (JuB) and jujubogenin, exhibited significant effects on the expression and activation of γ-amino-butyric acid A (GABA(A)) receptors. Our findings demonstrate that the metabolites of the saponin, not the original molecule, should be responsible for the specific bioactivities.

Influence of JuA in evoking communication changes between the small intestines and brain tissues of rats and the GABAA and GABAB receptor transcription levels of hippocampal neurons.

ETHNOPHARMACOLOGICAL RELEVANCE: Jujuboside A (JuA) is a main active ingredient of semen ziziphi spinosae, which can significantly reduce spontaneous activity in mammals, increase the speed of falling asleep, prolong the sleeping time as well as improve the sleeping efficiency. In this study, the mechanism and the pathway of the sedative and hypnotic effect of JuA were investigated. MATERIALS AND METHODS: After being treated with JuA (in vitro), the rat׳s small intestine tissues cultures were used to stimulate the brain tissues. Then 27 cytokine levels were detected in the two kinds of tissue culture via liquid protein chip technology; In addition, the cultured hippocampal neurons of rat were treated with JuA, and γ-aminobutyric acid (GABA) receptor subunits (GABAAα1, GABAAα5, GABAAß1 and GABABR1) mRNAs were evaluated by Real-time PCR. RESULTS: The levels of IL-1α, MIP-1α, IL-1ß and IL-2 were reduced significantly after 3h of treating the small intestine tissues with JuA (200µl/ml), and the concentration change rates, in order, were -59.3%, -3.59%, -50.1% and -49.4%; these cytokines were transmitted to brain tissues 2h later, which could lead to significant levels of reduction of IL-1α, IFN-γ, IP-10 and TNF-α; the concentration change rates were -62.4%, -25.7%, -55.2% and -38.5%, respectively. Further, the intercellular communication network diagram was mapped out, which could suggest the mechanism and the pathway of the sedative and hypnotic effect of JuA. The results also indicated that JuA (50µl/ml) increased significantly GABAAα1 receptor mRNAs and reduced GABABR1, mRNAs in hippocampal neurons after 24h of stimulation; however, all the mRNA transcription levels of GABAAα1,GABAAα5, GABAAß1 and GABABR1 receptors increased significantly after 48h. CONCLUSION: JuA performed its specific sedative and hypnotic effect through not only adjusting GABA receptors subunit mRNAs expression, but also down-regulating the secretion of relevant inflammation cytokines on the intestinal mucosal system to affect the intercellular cytokine network between nerve cells in the brain. This mechanism is similar to that of melatonin.

Microinjection of calcitonin in midbrain periaqueductal gray attenuates hyperalgesia in a chronic constriction injury rat model.

OBJECTIVES: As heat, pain is one of the most common clinical symptoms. Generally, calcitonin (CT) is prescribed as an analgesic agent for the treatment of pain, especially for the pain caused by osteoporosis or primary and metastatic bone tumor. However, the detailed mechanism remains unknown. MATERIALS AND METHODS: In this study, chronic constriction injury (CCI) rat model was created, and hot plate test and von frey filaments test were employed to evaluate thermal withdrawal latency (TWL) and mechanical withdrawal threshold (MWT), respectively. Immunohistochemistry staining and western blot analyses were used to assess the distribution and expression of calcitonin receptor (CT-R) in the midbrain periaqueductal gray (PAG), which was a pivotal site in the modulatory system for the endogenous pain. RESULTS: The TWL and MWT before the surgery (19.6±1.19 sec) were significantly longer than that at day 2 (12.5±1.60 sec), and day 14 (7.75±0.89 sec) (P< 0.01; P< 0.01), respectively. The TWL and MWT at day 14 were significantly increased compared to that at day 7 after microinjection of salmon calcitonin (sCT) with different doses. Interestingly, the expression of CT-R was up-regulated in neuropathic pain. Furthermore, the expression of CT-R was significantly up-regulated and algesia was remarkably relieved when CT was microinjected into PAG. CONCLUSION: These results suggested that an increased CT-R might be associated with hyperalgesia in CCI rat, and CT had a potent antinociceptive effect by the up-regulation of CT-R in the PAG. Thus, it might provide a potential approach for the treatment of bone pain.

Degradation kinetics of jujuboside b by rat intestinal flora in vitro with an RRLC-MS-MS method.

Jujuboside B (JuB) is a main bioactive saponin constituent of Ziziphi Spinosae Semen, which is a traditional herb for the treatment of insomnia and anxiety. However, the detailed metabolic mechanism of JuB is poorly understood. In this study, a novel method of rapid resolution liquid chromatography-triple quadrupole mass spectrometry was developed and validated for the analysis of JuB. With the method, the degradation kinetics of JuB by rat intestinal flora in vitro was investigated. The analysis was performed with an Agilent Eclipse Plus C18 (2.1 mm × 50 mm, 1.8 µm) column and an aqueous mobile phase (containing 0.1% formic acid) modified by methanol. The analyte was measured by multiple reaction-monitoring (MRM) modes with m/z 1043.3 → m/z 749.2. This method was validated with perfect accuracy, precision and limit of quantitation. It showed that jujuboside B (JuB) degradation started slowly as incubation with rat feces. The rate constant was correlated greatly with the concentration of sample solutions. Furthermore, some metabolites were elucidated with their chromatographic behavior and typical fragment ions. The results might help better interpret the metabolic and pharmacological mechanism of JuB.