Lidanpaidu prescription alleviates lipopolysaccharide-induced acute kidney injury by suppressing the NF-κB signaling pathway

Hederasaponin C inhibits LPS-induced acute kidney injury in mice by targeting TLR4 and regulating the PIP2/NF-κB/NLRP3 signaling pathway

Acute kidney injury (AKI) is a common clinical condition associated with increased incidence and mortality rates. Hederasaponin C (HSC) is one of the main active components of Pulsatilla chinensis (Bunge) Regel. HSC possesses various pharmacological activities, including anti-inflammatory activity. However, the protective effect of HSC against lipopolysaccharide (LPS)-induced AKI in mice remains unclear. Therefore, we investigated the protective effect of HSC against LPS-induced renal inflammation and the underlying molecular mechanisms. Herein, using MTT and LDH assays to assess both cell viability and LDH activity; using dual staining techniques to identify different cell death patterns; conducting immunoblotting, QRT-PCR, and immunofluorescence analyses to evaluate levels of protein and mRNA expression; employing immunoblotting, molecular docking, SPR experiments, and CETSA to investigate the interaction between HSC and TLR4; and studying the anti-inflammatory effects of HSC in the LPS-induced AKI. The results indicate that HSC inhibits the expression of TLR4 and the activation of NF-κB and PIP2 signaling pathways, while simultaneously suppressing the activation of the NLRP3 inflammasome. In animal models, HSC ameliorated LPS-induced AKI and diminished inflammatory response and the level of renal injury markers. These findings suggest that HSC has potential as a therapeutic agent to mitigate sepsis-related AKI.

Allicin Alleviated LPS-Induced Mastitis via the TLR4/NF-κB Signaling Pathway in Bovine Mammary Epithelial Cells

Dairy farming is the most important economic activity in animal husbandry. Mastitis is the most common disease in dairy cattle and has a significant impact on milk quality and yield. The natural extract allicin, which is the main active ingredient of the sulfur-containing organic compounds in garlic, has anti-inflammatory, anticancer, antioxidant, and antibacterial properties; however, the specific mechanism underlying its effect on mastitis in dairy cows needs to be determined. Therefore, in this study, whether allicin can reduce lipopolysaccharide (LPS)-induced inflammation in the mammary epithelium of dairy cows was investigated. A cellular model of mammary inflammation was established by pretreating bovine mammary epithelial cells (MAC-T) with 10 µg/mL LPS, and the cultures were then treated with varying concentrations of allicin (0, 1, 2.5, 5, and 7.5 µM) added to the culture medium. MAC-T cells were examined using RT-qPCR and Western blotting to determine the effect of allicin. Subsequently, the level of phosphorylated nuclear factor kappa-B (NF-κB) was measured to further explore the mechanism underlying the effect of allicin on bovine mammary epithelial cell inflammation. Treatment with 2.5 µM allicin considerably decreased the LPS-induced increase in the levels of the inflammatory cytokines interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor-α (TNF-α) and inhibited activation of the NOD-like receptor protein 3 (NLRP3) inflammasome in cow mammary epithelial cells. Further research revealed that allicin also inhibited the phosphorylation of inhibitors of nuclear factor kappa-B-α (IκB-α) and NF-κB p65. In mice, LPS-induced mastitis was also ameliorated by allicin. Therefore, we hypothesize that allicin alleviated LPS-induced inflammation in the mammary epithelial cells of cows probably by affecting the TLR4/NF-κB signaling pathway. Allicin will likely become an alternative to antibiotics for the treatment of mastitis in cows.

MiR-494-mediated Effects on the NF-κB Signaling Pathway Regulate Lipopolysaccharide-Induced Acute Kidney Injury in Mice

OBJECTIVE

To explore the effects of miR-494 inhibition through the NF-κB signaling pathway on lipopolysaccharide (LPS)-induced acute kidney injury (AKI) mouse model.

METHODS

The AKI mice induced by LPS were treated with miR-494 antagomir, and the kidney parameters and indicators of oxidative stress were detected. HE and TUNEL staining were performed to observe the kidney histopathology and the apoptosis in renal tubular epithelial cells (RTECs), respectively. The ROS level was measured using dihydroethidium (DHE) staining. In addition, qRT-PCR, western blotting, immunohistochemistry (IHC), and ELISA were also used to detect gene or protein expression.

RESULTS

LPS-induced AKI mice injected with the miR-494 antagomir showed reduced blood urea nitrogen (BUN) and serum creatinine (Cr) with improved kidney histopathology. The expression levels of p-IKKα/β, p-IκBα and p65 NF-κB in the nucleus were increased in kidney tissues from the LPS-induced AKI mice, and they were decreased by the miR-494 antagomir. Moreover, the results of IHC showed that the miR-494 antagomir downregulated p65 NF-κB in kidney tissues from the LPS-induced AKI mice, accompanied by decreased levels of TNF-α, IL-1β, IL-6, MDA, NO, and ROS but increased levels of SOD and GSH. In addition, the LPS-induced AKI mice had increased apoptosis in RTECs, as well as increased Caspase-3 and Bax and decreased Bcl-2, which were reversed by the miR-494 antagomir.

CONCLUSIONS

The inhibition of miR-494 could reduce inflammatory responses and improve oxidative stress in kidney tissues from LPS-induced AKI mice by blocking the NF-κB pathway accompanying by reduced apoptosis in RTECs.

MIR210HG Aggravates Sepsis-Induced Inflammatory Response of Proximal Tubular Epithelial Cell via the NF-κB Signaling Pathway

PURPOSE

Acute kidney injury (AKI) is a serious complication of sepsis and is characterized by inflammatory response. MicroRNA-210 host gene (MIR210HG) is upregulated in human proximal tubular epithelial cells under treatment of inflammatory cytokines. This study aimed to explore the role of MIR210HG in sepsis-induced AKI.

MATERIALS AND METHODS

Cell viability was detected by a cell counting kit 8 assay. The levels of proinflammatory cytokines were detected by enzyme-linked immunosorbent assay kits. The protein levels of p65, IκBα, and p-IκBα were examined by western blot analysis. The nuclear translocation of nuclear factor kappa B (NF-κB) was detected by immunofluorescence assay. The histological changes of kidneys were analyzed by hematoxylin and eosin staining assay.

RESULTS

Lipopolysaccharide (LPS) treatment significantly inhibited cell viability and increased productions of proinflammatory cytokines in proximal tubular epithelial cells (HKC-8). Additionally, MIR210HG levels in HKC-8 cells were increased by LPS treatment. MIR210HG silencing inhibited the LPS-induced cell inflammatory response. MIR210HG activated the NF-κB signaling pathway by promoting the phosphorylation of IκBα and nuclear translocation of p65. Rescue assays revealed that the MIR210HG-induced increase of cytokines levels and decline of cell viability were rescued by QNZ treatment. Knockdown of MIR210HG decreased blood urea nitrogen, serum creatinine, and proinflammatory cytokine levels in AKI rats. Moreover, the knockdown of MIR210HG protected against AKI-induced histological changes of kidneys in rats.

CONCLUSION

MIR210HG promotes sepsis-induced inflammatory response of HKC-8 cells by activating the NF-κB signaling pathway. This novel discovery may be helpful for the improvement of sepsis-induced AKI.

Anti-inflammatory Effect of Astragalin and Chlorogenic Acid on Escherichia coli-Induced Inflammation of Sheep Endometrial Epithelium Cells

Endometritis is one of the main diseases which harm sheep husbandry. Astragalin and chlorogenic acid (CGA) are common active ingredients of traditional Chinese medicine (TCM) with immunoprotective, antioxidant, and anti-inflammatory properties. In the present study, sheep endometrial epithelium cells (SEECs) were successfully purified and identified, and the in vitro inflammation model of SEECs induced by Escherichia coli (E. coli) was successfully established. To explore the effect of astragalin and CGA on the inflammation induced by E. coli and its potential mechanism, six groups were set up, namely, group C, M, astragalin, CGA, BAY, and STR. Cells in group C were incubated with DMEM/F12 for 6 h, while cells in group M, astragalin, CGA, BAY, and STR were incubated with DMEM/F12, astragalin, CGA, BAY, and STR for 3 h, respectively, followed by E. coli infection at a multiplicity of infection (MOI) of 1 E. coli per cell for 3 h. Subsequently, the cells and the supernatant were collected to detect the expression of genes in the toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) pathway by ELISA, qPCR, and western blot. The results showed that E. coli could induce inflammation of SEECs in vitro, while astragalin and CGA could alleviate the inflammatory response induced by E. coli via inhibiting the activation of the TLR4/NF-κB signaling pathway, which provides a theoretical and experimental foundation for preventing sheep endometritis clinically.

2-methylquinazoline derivative F7 as a potent and selective HDAC6 inhibitor protected against rhabdomyolysis-induced acute kidney injury

Histone deacetylases 6 (HDAC6) has been reported to be involved in the pathogenesis of rhabdomyolysis-induced acute kidney injury (AKI). Selective inhibition of HDAC6 activity might be a potential treatment for AKI. In our lab, N-hydroxy-6-(4-(methyl(2-methylquinazolin-4-yl)amino)phenoxy)nicotinamide (F7) has been synthesized and inhibited HDAC6 activity with the IC₅₀ of 5.8 nM. However, whether F7 possessed favorable renoprotection against rhabdomyolysis-induced AKI and the involved mechanisms remained unclear. In the study, glycerol-injected mice developed severe AKI symptoms as indicated by acute renal dysfunction and pathological changes, accompanied by the overexpression of HDAC6 in tubular epithelial cells. Pretreatment with F7 at a dose of 40 mg/kg/d for 3 days significantly attenuated serum creatinine, serum urea, renal tubular damage and suppressed renal inflammatory responses. Mechanistically, F7 enhanced the acetylation of histone H3 and α-tubulin to reduce HDAC6 activity. Glycerol-induced AKI triggered multiple signal mediators of NF-κB pathway as well as the elevation of ERK1/2 protein and p38 phosphorylation. Glycerol also induced the high expression of proinflammatory cytokine IL-1β and IL-6 in kidney and human renal proximal tubule HK-2 cells. Treatment of F7 notably improved above-mentioned inflammatory responses in the injured kidney tissue and HK-2 cell. Overall, these data highlighted that 2-methylquinazoline derivative F7 inhibited renal HDAC6 activity and inflammatory responses to protect against rhabdomyolysis-induced AKI.

Zhen-wu-tang ameliorates membranous nephropathy rats through inhibiting NF-κB pathway and NLRP3 inflammasome

BACKGROUND

Zhen-wu-tang (ZWT), a traditional herbal formula, has been widely used for the treatment of kidney diseases in clinics, but the underlying molecular mechanisms have not been fully understood.

PURPOSE

Inflammation mediated podocyte injury has been reported to constitute a crucial part in the pathogenesis of membranous nephropathy (MN). The current study was designed to evaluate the effect of ZWT on MN related to nuclear factor-κB (NF-κB) pathway and NLRP3 inflammasome.

METHODS

The main components of ZWT were identified by 3D-ultra performance liquid chromatography (3D-UPLC) assay. A MN rat model induced by cationic-bovine serum albumin (C-BSA) and podocytes stimulated by TNF-α were used in this study. The 24 h urine protein, serum total cholesterol (TC) and triglyceride (TG), as well as kidney histology were measured to evaluate kidney damage. The expressions of IgG and complement 3 (C3), and the co-localization of NLRP3 and ASC were detected by immunofluorescence. The expressions of podocyte injury related protein desmin, podocin were measured by immunohistochemistry and western blot. Cell vitality of cultured podocytes was detected by MTT assay, as apoptosis assay was measured via flow cytometry. The protein expressions of p-p65, p-IκBα, NLRP3, Caspase-1, IL-1β were detected by western blot.

RESULTS

Our results showed that ZWT significantly ameliorated kidney damage in MN model rats by decreasing the levels of 24 h urine protein, TC and TG. ZWT also improved renal histology and reduced the expressions of IgG and C3 in glomerulus. In addition, ZWT lessened the expressions of desmin, but increased podocin expression in vivo and vitro. ZWT protected cultured podocytes by maintaining cell vitality and inhibiting apoptosis. Moreover, we found that ZWT suppressed the expressions of NLRP3, Caspase-1, IL-1β and the co-localization of NLRP3 and ASC. Furthermore, the inhibition of NLRP3 inflammasome under ZWT treatment were accompanied by down-regulation of NF-κB pathway, as the p-p65 and p-IκBα protein expression were reduced.

CONCLUSIONS

Our present study indicates that the inhibition of NF-κB pathway and NLRP3 inflammasome might be the potential mechanisms for the therapeutic effects of ZWT against MN.

The Effect of Overexpression of the Enhancer of Zeste Homolog 1 (EZH1) Gene on Aristolochic Acid-Induced Injury in HK-2 Human Kidney Proximal Tubule Cells In Vitro

Background

Acute kidney injury (AKI) involves the renal tubular epithelium. The enhancer of zeste homolog 1 (EZH1) gene has a role in cell development and differentiation. This study aimed to investigate the effect of overexpression of the EZH1 gene on aristolochic acid-induced injury in HK-2 human kidney proximal tubule epithelial cells in vitro.

Material/Methods

The HK-2 cells were cultured and treated with aristolochic acid and the effects of aristolochic acid-injury were evaluated using a cell counting kit-8 (CCK-8) assay. Overexpression of EZH1 used gene plasmid transfection into HK-2 cells. The cell apoptosis rate and levels of intracellular reactive oxygen species (ROS) were measured using flow cytometry. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were performed to determine the expressions of inflammatory cytokines including interleukin (IL)-1β, IL-6, tumor necrosis factor-α (TNF-α), apoptosis-related genes, and the downstream target genes of NF-κB signaling pathway, including NFKBIA, CXCL8, and cyclin D1.

Results

Aristolochic acid inhibited HK-2 cell viability, induced cell apoptosis, increased the levels of ROS and inflammatory cytokines, including IL-1β, IL-6, TNF-α, and activated the NF-κB pathway. Overexpression the EZH1 gene inhibited HK-2 cell apoptosis, reduced ROS levels, and down-regulated the expressions of IL-1β, IL-6, TNF-α, Bax and Cyt C mRNA and protein, and increased the expressions of Bcl-2 and NFKBIA, CXCL8 and cyclin D1, indicating that overexpression of EZH1 suppressed NF-κB signaling in aristolochic acid-injured HK-2 cells.

Conclusions

Overexpression of EZH1 reduced HK-2 cell injury induced by aristolochic acid in vitro by inhibition of NF-κB signaling.

Nuciferine alleviates LPS-induced mastitis in mice via suppressing the TLR4-NF-κB signaling pathway

BACKGROUND

Nuciferine, a major bioactive component from the lotus leaf, has been reported to have notable anti-inflammatory activities such as renal inflammation and acute lung injury in previous studies. Mastitis is one of the most prevalent diseases in the dairy cattle, which causes large economic losses for the dairy industry. However, the effects of nuciferine on lipopolysaccharide (LPS)-induced mastitis have not been reported.

METHODS AND RESULTS

Here, we investigated the anti-inflammatory effects of nuciferine on LPS-induced mastitis in mice and illuminated its potential mechanism on the TLR4-mediated signaling pathway in mouse mammary epithelial cells (mMECs). Histopathological changes and myeloperoxidase (MPO) activity assay showed that nuciferine treatment significantly alleviated the LPS-induced injury of mammary gland flocculus, inflammatory cells infiltration. qPCR and ELISA assays indicated that nuciferine dose-dependently reduced the levels of TNF-α and IL-1β, which indicated that nuciferine might have therapeutic effects on mastitis. Furthermore, nuciferine treatment significantly decreased the expression of TLR4 in a dose-dependent manner. Besides, nuciferine was also found to suppress LPS-induced NF-κB activation.

CONCLUSION

These findings indicate that nuciferine potently ameliorates LPS-induced mastitis by inhibition of the TLR4-NF-κB signaling pathway.

Effect of Da-Cheng-Qi decoction for treatment of acute kidney injury in rats with severe acute pancreatitis

Background

The traditional Chinese formula Da-Cheng-Qi-decoction (DCQD) has been used to treat acute pancreatitis for decades. DCQD could ameliorate the disease severity and the complications of organ injuries, including those of the liver and lungs. However, the pharmacological effects in the kidney, a target organ, are still unclear. This study aimed to investigate the herbal tissue pharmacology of DCQD for acute kidney injury (AKI) in rats with severe acute pancreatitis (SAP).

Methods

Rats were randomly divided into the sham-operation group (SG), the model group (MG) and the low-, medium- and high-dose treatment groups (LDG, MDG, and HDG, respectively). Sodium taurocholate (3.5%) was retrogradely perfused into the biliopancreatic duct to establish the model of SAP in rats. Different doses of DCQD were administered to the treatment groups 2 h after the induction of SAP. The major components of DCQD in kidney tissues were detected by HPLC–MS/MS. Inflammatory mediators in the kidney tissues, as well as serum creatinine (Scr), blood urea nitrogen (BUN) and pathologic scores, were also evaluated.

Results

Ten components of DCQD were detected in the kidneys of the treatment groups, and their concentrations increased dose-dependently. Compared with the SG, the levels of inflammatory mediators, Scr, BUN and pathological scores in the MG were obviously increased (p < 0.05). The high dose of DCQD showed a maximal effect in downregulating the pro-inflammatory mediators interleukin-6 (IL)-6 and tumour necrosis factor-α (TNF-α), upregulating anti-inflammatory mediators IL-4 and IL-10 in the kidney and alleviating the pathological damages. DCQD decreased the pancreas and kidney pathological scores of rats with SAP, especially in the HDG (p < 0.05). Compared with the MG, the level of Scr in the HDG was significantly decreased (p < 0.05).

Conclusions

DCQD ameliorated AKI in rats with SAP via regulating the inflammatory response, which might be closely related to the distribution of its components in the kidney.

Electronic supplementary material

The online version of this article (10.1186/s13020-018-0195-8) contains supplementary material, which is available to authorized users.