Application of targeted liposomes-based salvianolic acid A for the treatment of ischemic stroke.

Novel therapeutics for the treatment of ischemic stroke remains to be the unmet clinical needs. Previous studies have indicated that salvianolic acid A (SAA) is a promising candidate for the treatment of the brain diseases. However, SAA has poor absolute bioavailability and does not efficiently cross the intact blood-brain barrier (BBB), which limit its efficacy. To this end we developed a brain-targeted liposomes for transporting SAA via the BBB by incorporating the liposomes to a transport receptor, insulin-like growth factor-1 receptor (IGF1R). The liposomes were prepared by ammonium sulfate gradients loading method. The prepared SAA-loaded liposomes (Lipo/SAA) were modified with IGF1R monoclonal antibody to generate IGF1R antibody-conjugated Lipo/SAA (IGF1R-targeted Lipo/SAA). The penetration of IGF1R-targeted Lipo/SAA into the brain was confirmed by labeling with Texas Red, and their efficacy were evaluate using middle cerebral artery occlusion (MCAO) model. The results showed that IGF1R-targeted Lipo/SAA are capable of transporting SAA across the BBB into the brain, accumulation in brain tissue, and sustained releasing SAA for several hours. Administration o IGF1R-targeted Lipo/SAA notably reduced infarct size and neuronal damage, improved neurological function and inhibited cerebral inflammation, which had much higher efficiency than no-targeted SAA.

Minor protopanaxadiol type sapogenins from the alkali hydrolysate of stems-leaves of Panax notoginseng.

Two new protopanaxadiol type sapogenins, (3ß,12ß)-3,12,20-trihydroxydammar-24-en-26-al (1) and (3ß,12ß)-3,12,20-trihydroxydammar-24-en-26-oic acid (2), were isolated from the alkali hydrolysate of stems-leaves of Panax notoginseng, along with seven known analogues (3-9). Their structures were elucidated by spectroscopic analyses and single-crystal X-ray diffraction. Compound 2 and the known sapogenins 5-8 displayed weak to moderate inhibition of NO production in LPS-induced RAW264.7 macrophages with IC50 values from 44.5 to 143.6 µM, respectively.

The CSB chromatin remodeler regulates PARP1- and PARP2-mediated single-strand break repair at actively transcribed DNA regions.

Efficient repair of oxidized DNA is critical for genome-integrity maintenance. Cockayne syndrome protein B (CSB) is an ATP-dependent chromatin remodeler that collaborates with Poly(ADP-ribose) polymerase I (PARP1) in the repair of oxidative DNA lesions. How these proteins integrate during DNA repair remains largely unknown. Here, using chromatin co-fractionation studies, we demonstrate that PARP1 and PARP2 promote recruitment of CSB to oxidatively-damaged DNA. CSB, in turn, contributes to the recruitment of XRCC1, and histone PARylation factor 1 (HPF1), and promotes histone PARylation. Using alkaline comet assays to monitor DNA repair, we found that CSB regulates single-strand break repair (SSBR) mediated by PARP1 and PARP2. Strikingly, CSB's function in SSBR is largely bypassed when transcription is inhibited, suggesting CSB-mediated SSBR occurs primarily at actively transcribed DNA regions. While PARP1 repairs SSBs at sites regardless of the transcription status, we found that PARP2 predominantly functions in actively transcribed DNA regions. Therefore, our study raises the hypothesis that SSBR is executed by different mechanisms based on the transcription status.

Piceatannol-3'-O-ß-d-glucopyranoside alleviates nephropathy via regulation of High mobility group B-1 (HMGB1)/Toll-like receptor 4 (TLR4)/Nuclear factor kappa B (NF-κB) signalling pathway.

OBJECTIVES: Nephrotic syndrome (NS) remains a therapeutic challenge for nephrologists. Piceatannol-3'-O-ß-d-glucopyranoside (PG) is a major active ingredient in Quzha. The purpose of the study was to assess the renoprotection of PG. METHODS: In vitro, the podocyte protection of PG was assessed in MPC-5. SD rats were injected with adriamycin to induce nephropathy in vivo. The determination of biochemical changes and inflammatory cytokines was performed, and pathological changes were examined by histopathological examination. Immunostaining and western blot analyses were used to analyse expression levels of proteins. KEY FINDINGS: The results showed that PG improved adriamycin-induced podocyte injury, attenuated nephropathy, improved hypoalbuminemia and hyperlipidaemia, and lowered cytokine levels. The podocyte protection of PG was further verified by reduction of desmin and increasing synaptopodin expression. Furthermore, treatment with PG down-regulated the expression of HMGB1, TLR4 and NF-κB along with its upstream regulator, IKKß and yet up-regulated IκBα expression by western blot analysis. CONCLUSIONS: Overall, our data showed that PG has a favourable renoprotection in experimental nephrosis, apparently by amelioration of podocyte injury. PG might mediate these effects via modulation of the HMGB1/TLR4/NF-κB signalling pathway. The study first provides a promising leading compound for the treatment of NS.

Effectiveness and safety of acupuncture for insulin resistance in women with polycystic ovary syndrome: A systematic review and meta-analysis.

Objective: To perform a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate acupuncture's clinical effect on insulin resistance (IR) in women with polycystic ovary syndrome (PCOS). Methods: PubMed, Cochrane Library, Embase databases, and Chinese databases, including China National Knowledge Infrastructure, Technology Journal Database, and Wanfang Database, were searched without language restrictions from inception to December 20, 2021. Only RCTs in which acupuncture had been examined as the sole or adjunctive PCOS-IR treatment were included. Our primary endpoint was the homeostasis model assessment of insulin resistance (HOMA-IR). The secondary outcomes were fasting blood glucose (FBG), fasting insulin (FINS), body mass index (BMI), and adverse events. Results: Our analysis included 17 eligible RCTs (N = 1511 participants). Compared with other treatments, acupuncture therapy yielded a greater mean reduction in HOMA-IR (MD = -0.15; 95% CI, -0.27 to -0.03; P = 0.01) and BMI (MD = -1.47; 95% CI, -2.46 to -0.47; P = 0.004). Besides acupuncture was associated with a lower risk of adverse events than other treatments (RR, 0.15; 95% CI, 0.10 to 0.22; P < 0.01). Additionally, the combination treatment of acupuncture and medicine is more effective in improving HOMA-IR (MD = -0.91; 95% CI, -1.11 to -0.71; P < 0.01), FBG (MD = -0.30; 95% CI, -0.56 to -0.04; P = 0.02), FINS (MD = -2.33; 95% CI, -2.60 to -2.06; P < 0.01) and BMI (MD = -1.63; 95% CI, -1.94 to -1.33; P < 0.01) than medicine alone. Conclusions: Acupuncture is relatively effective in improving HOMA-IR and BMI in PCOS-IR. Besides, it's safer than other treatments and could be an adjuvant strategy for improving PCOS-IR. Further large-scale, long-term RCTs with strict methodological standards are justified.

Role of toll-like receptors in the pathogenesis of COVID-19: Current and future perspectives.

The coronavirus disease 2019 (COVID-19) pandemic underlines a persistent threat of respiratory tract infectious diseases and warrants preparedness for a rapid response. At present, COVID-19 has had a serious social impact and imposed a heavy global burden on public health. The exact pathogenesis of COVID-19 has not been fully elucidated. Since the outbreak of COVID-19, a renewed attention has been brought to Toll-like receptors (TLRs). Available data and new findings have demonstrated that the interaction of human TLRs and SARS-CoV-2 is a vital mediator of COVID-19 immunopathogenesis. TLRs such as TLR2, 4, 7 and 8 are potentially important in viral combat and activation of immunity in patients with COVID-19. Therapeutics targeting TLRs are currently considered promising options against the pandemic. A number of TLR-targeting immunotherapeutics are now being investigated in preclinical studies and different phases of clinical trials. In addition, innovative vaccines based on TLRs under development could be a promising approach for building a new generation of vaccines to solve the current challenges. In this review, we summarize recent progress in the role of TLRs in COVID-19, focusing the new candidate drugs targeting TLRs, the current technology and potential paths forward for employing TLR agonists as vaccine adjuvants.

Non-clinical safety evaluation of salvianolic acid A: acute, 4-week intravenous toxicities and genotoxicity evaluations.

BACKGROUND: Toxicological problem associated with herbal medicine is a significant public health problem. Hence, it is necessary to elaborate on the safety of herbal medicine. Salvianolic acid A (SAA) is a major active compound isolated from Danshen, a popular herbal drug and medicinal food plant in China. The aim of the present study was to explore the toxicological profile of SAA. METHODS: The acute toxicity studies were performed in mice and Beagle dogs with single administration with SAA. A 4-week subchronic toxicity was test in dogs. SAA was intravenously administered at doses of 20, 80 and 300 mg/kg. Clinical observation, laboratory testing and necropsy and histopathological examination were performed. The genotoxic potential of SAA was evaluated by 2 types of genotoxicity tests: a reverse mutation test in bacteria and bone marrow micronucleus test in mice. RESULTS: In acute toxicities, the LD50 of SAA is 1161.2 mg/kg in mice. The minimum lethal dose (MLD) and maximal non-lethal dose (MNLD) of SAA were 682 mg/kg and 455 mg/kg in dogs, respectively. The approximate lethal dose range was 455-682 mg/kg. In the study of 4-week repeated-dose toxicity in dogs, focal necrosis in liver and renal tubular epithelial cell, the decrease in relative thymus weight, as well as abnormal changes in biochemical parameters, were observed in SAA 80 or 300 mg/kg group. The no observed adverse effect level (NOAEL) of SAA was 20 mg/kg. Thymus, liver and kidneys were the toxic targets. These toxic effects were transient and reversible. These results indicated that it should note examination of liver and kidney function during the administration of SAA in clinic. Furthermore, SAA had no mutagenic effect at any tested doses. CONCLUSION: These results provide new toxicological information of SAA for its clinical application and functional food consumption.

Analyzing the Interaction of RBPJ with Mitotic Chromatin and Its Impact on Transcription Reactivation upon Mitotic Exit.

The sequence-specific transcription factor RBPJ, also known as CSL (CBF1, Su(H), Lag1), is an evolutionarily conserved protein that mediates Notch signaling to guide cell fates. When cells enter mitosis, DNA is condensed and most transcription factors dissociate from chromatin; however, a few, select transcription factors, termed bookmarking factors, remain associated. These mitotic chromatin-bound factors are believed to play important roles in maintaining cell fates through cell division. RBPJ is one such factor that remains mitotic chromatin associated and therefore could function as a bookmarking factor. Here, we describe how to obtain highly purified mitotic cells from the mouse embryonal carcinoma cell line F9, perform chromatin immunoprecipitation with mitotic cells, and measure the first run of RNA synthesis upon mitotic exit. These methods serve as basis to understand the roles of mitotic bookmarking by RBPJ in propagating Notch signals through cell division.

Dynamic Interplay between Cockayne Syndrome Protein B and Poly(ADP-Ribose) Polymerase 1 during Oxidative DNA Damage Repair.

Oxidative stress contributes to numerous diseases, including cancer. CSB is an ATP-dependent chromatin remodeler critical for oxidative stress relief. PARP1 is the major sensor for DNA breaks and fundamental for efficient single-strand break repair. DNA breaks activate PARP1, leading to the synthesis of poly(ADP-ribose) (PAR) on itself and neighboring proteins, which is crucial for the recruitment of DNA repair machinery. CSB and PARP1 interact; however, how CSB mechanistically participates in oxidative DNA damage repair mediated by PARP1 remains unclear. Using chromatin immunoprecipitation followed by quantitative PCR, we found that CSB and PARP1 facilitate each other's chromatin association during the onset of oxidative stress, and that CSB facilitates PARP1 removal when the level of chromatin-bound CSB increases. Furthermore, by monitoring chromatin PAR levels using Western blot analysis, we found that CSB sustains the DNA damage signal initiated by PARP1, and may prevent PARP1 overactivation by facilitating DNA repair. By assaying cell viability in response to oxidative stress, we further demonstrate that PARP1 regulation by CSB is a major CSB function in oxidatively-stressed cells. Together, our study uncovers a dynamic interplay between CSB and PARP1 that is critical for oxidative stress relief.

Salvianolic acid A attenuates steroid resistant nephrotic syndrome through suPAR/uPAR-αvß3 signaling Inhibition.

ETHNOPHARMACOLOGICAL RELEVANCE: Salvianolic acid A (SAA) is extracted from traditional Chinese medicine Salvia miltiorrhiza and is the main water-soluble and the biologically active ingredient. SAA possesses a variety of pharmacological activities and has an excellent protective effect on kidney disease, especially steroid resistant nephrotic syndrome (SRNS), and has advantages in improving the efficacy of glucocorticoids, but its mechanism needs to be further explored. PURPOSE: The study was designed to explore the effect of suPAR and uPAR in SRNS patients and evaluate the potential effect of SAA in improving podocyte steroid resistance and explore its mechanism. METHODS AND MATERIALS: The ELISA kits were used to detect the levels of suPAR in the blood and urine of subjects. The levels of uPAR, GRα, and GRß expression in renal tissues of SRNS patients was detected by immunohistochemistry and analyzed using the Pearson method. In vitro studies, steroid resistance model was induced by the TNF-α and IFN-γ. The protein and mRNA expression of Nephrin, GR, GRα and GRß were analyzed using western blot and qRT-PCR. The activity of GR-DNA binding was detected by using TransAM™ GR kits. Adriamycin further induced steroid resistance podocyte. Flow cytometry was used to detect the effect of SAA on podocyte apoptosis. ELISA assay was used to detect the suPAR expression in the podocyte supernatant. Western blot and qRT-PCR were used to detect the protein and mRNA expression of uPAR and Nephrin in podocytes. RESULTS: The serum and urine levels of suPAR were conspicuously higher in SRNS patients than healthy volunteers and SSNS patients, and the expression of uPAR in renal tissue of SRNS patients is negatively correlated with GRα, but positively correlated with GRß. The combination of TNF-α and IFN-γ could conspicuously increase the GRß expression and reduce GRα/GRß, and induce steroid resistance in podocytes. Moreover, we found that SAA could reduce the apoptosis of podocytes and suppress the expression of suPAR/uPAR, and increase the expression of Nephrin. CONCLUSION: The level of suPAR and uPAR expression may have important value in predicting glucocorticoids resistance in patients with idiopathic nephrotic syndrome (INS). The combination of TNF-α and IFN-γ induce podocytes can establish steroid resistance model in vitro. SAA could improve glucocorticoids resistance of podocyte which can be attributed in part to regulate the suPAR/uPAR-αvß3 signaling pathway.

A Novel Flow Cytometric Assay to Identify Inhibitors of RBPJ-DNA Interactions.

Notch signaling is often involved in cancer cell initiation and proliferation. Aberrant Notch activation underlies more than 50% of T-cell acute lymphoblastic leukemia (T-ALL); accordingly, chemicals disrupting Notch signaling are of potential to treat Notch-dependent cancer. Here, we developed a flow cytometry-based high-throughput assay to identify compounds that disrupt the interactions of DNA and RBPJ, the major downstream effector of Notch signaling. From 1492 compounds, we identified 18 compounds that disrupt RBPJ-DNA interactions in a dose-dependent manner. Cell-based assays further revealed that auranofin downregulates Notch-dependent transcription and decreases RBPJ-chromatin interactions in cells. Most strikingly, T-ALL cells that depend on Notch signaling for proliferation are more sensitive to auranofin treatment, supporting the notion that auranofin downregulates Notch signaling by disrupting RBPJ-DNA interaction. These results validate the feasibility of our assay scheme to screen for additional Notch inhibitors and provide a rationale to further test the use of auranofin in treating Notch-dependent cancer.

Curcumin, as a pleiotropic agent, improves doxorubicin-induced nephrotic syndrome in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Curcumin, a phenolic compound extracted from the rhizome of turmeric (Curcuma longa L.), has been reported to have broad biological functions including potent antioxidant and renoprotective effects. It has been reported that Curcumin has a certain protective effect on the kidney. However, its mechanism of action needs further study. AIM OF THE STUDY: The present research aims at investigating the therapeutic effects and its underlying mechanism of curcumin on NS. MATERIALS AND METHODS: The conditionally immortalized mouse podocyte cell line was utilized to evaluate the podocyte-protective effect of curcumin and its effects on NF-κB pathway and Nrf2/ARE pathway in podocyte in vitro. Furthermore, the DOX-induced NS rats were utilized to investigate the therapeutic effects and its underlying mechanism of curcumin against NS in vivo. RESULTS: The consequences of this study revealed that curcumin activated Nrf2, inhibited NF-κB pathway and up-regulated podocin in DOX-induced podocyte. Further research results showed that curcumin can considerably alleviate proteinuria and improve hypoalbuminemia in NS rats, and lower blood lipid levels to alleviate hyperlipidemia in NS rats, indicating that curcumin has significant therapeutic effects on rat NS. Further observation by electron microscopy and detection showed that curcumin can improve renal function and podocyte injury, which may be related to the repairment of mRNA expression and podocin protein. Interestingly, the results of the blood rheology test showed that curcumin can effectively reduce whole blood viscosity (WBV) and plasma viscosity (PV), and reduce hematocrit (Hct). In addition, the oxidative stress state of kidney in NS rats was considerably reversed by curcumin, which may be achieved by activating Nrf2 and increasing the expression of antioxidant enzymes HO-1, NQO-1. We also found that NF-κB pathway is activated in the kidney of NS rats, and curcumin can inhibit the activation of NF-κB by down-regulating the expression of NF-κB p65, reducing the level of p-IκBα and up-regulating the expression of IκBα. CONCLUSION: These findings suggest that curcumin, as a multifunctional agent, exerts a protective effect on DOX-induced nephrotic syndrome in rats, which provides a pharmacological basis for the further development of curcumin and also provides a basis for the advantages of multi-targeted drugs in the processing of NS.

HDAC1 negatively regulates selective mitotic chromatin binding of the Notch effector RBPJ in a KDM5A-dependent manner.

Faithful propagation of transcription programs through cell division underlies cell-identity maintenance. Transcriptional regulators selectively bound on mitotic chromatin are emerging critical elements for mitotic transcriptional memory; however, mechanisms governing their site-selective binding remain elusive. By studying how protein-protein interactions impact mitotic chromatin binding of RBPJ, the major downstream effector of the Notch signaling pathway, we found that histone modifying enzymes HDAC1 and KDM5A play critical, regulatory roles in this process. We found that HDAC1 knockdown or inactivation leads to increased RBPJ occupancy on mitotic chromatin in a site-specific manner, with a concomitant increase of KDM5A occupancy at these sites. Strikingly, the presence of KDM5A is essential for increased RBPJ occupancy. Our results uncover a regulatory mechanism in which HDAC1 negatively regulates RBPJ binding on mitotic chromatin in a KDM5A-dependent manner. We propose that relative chromatin affinity of a minimal regulatory complex, reflecting a specific transcription program, renders selective RBPJ binding on mitotic chromatin.

Poly(ADP-ribose) polymerase 1 (PARP1) promotes oxidative stress-induced association of Cockayne syndrome group B protein with chromatin.

Cockayne syndrome protein B (CSB) is an ATP-dependent chromatin remodeler that relieves oxidative stress by regulating DNA repair and transcription. CSB is proposed to participate in base-excision repair (BER), the primary pathway for repairing oxidative DNA damage, but exactly how CSB participates in this process is unknown. It is also unclear whether CSB contributes to other repair pathways during oxidative stress. Here, using a patient-derived CS1AN-sv cell line, we examined how CSB is targeted to chromatin in response to menadione-induced oxidative stress, both globally and locus-specifically. We found that menadione-induced, global CSB-chromatin association does not require CSB's ATPase activity and is, therefore, mechanistically distinct from UV-induced CSB-chromatin association. Importantly, poly(ADP-ribose) polymerase 1 (PARP1) enhanced the kinetics of global menadione-induced CSB-chromatin association. We found that the major BER enzymes, 8-oxoguanine DNA glycosylase (OGG1) and apurinic/apyrimidinic endodeoxyribonuclease 1 (APE1), do not influence this association. Additionally, the level of γ-H2A histone family member X (γ-H2AX), a marker for dsDNA breaks, was not increased in menadione-treated cells. Therefore, our results support a model whereby PARP1 localizes to ssDNA breaks and recruits CSB to participate in DNA repair. Furthermore, this global CSB-chromatin association occurred independently of RNA polymerase II-mediated transcription elongation. However, unlike global CSB-chromatin association, both PARP1 knockdown and inhibition of transcription elongation interfered with menadione-induced CSB recruitment to specific genomic regions. This observation supports the hypothesis that CSB is also targeted to specific genomic loci to participate in transcriptional regulation in response to oxidative stress.

Mechanistic insights into the regulation of transcription and transcription-coupled DNA repair by Cockayne syndrome protein B.

Cockayne syndrome protein B (CSB) is a member of the SNF2/SWI2 ATPase family and is essential for transcription-coupled nucleotide excision DNA repair (TC-NER). CSB also plays critical roles in transcription regulation. CSB can hydrolyze ATP in a DNA-dependent manner, alter protein-DNA contacts and anneal DNA strands. How the different biochemical activities of CSB are utilized in these cellular processes have only begun to become clear in recent years. Mutations in the gene encoding CSB account for majority of the Cockayne syndrome cases, which result in extreme sun sensitivity, premature aging features and/or abnormalities in neurology and development. Here, we summarize and integrate recent biochemical, structural, single-molecule and somatic cell genetic studies that have advanced our understanding of CSB. First, we review studies on the mechanisms that regulate the different biochemical activities of CSB. Next, we summarize how CSB is targeted to regulate transcription under different growth conditions. We then discuss recent advances in our understanding of how CSB regulates transcription mechanistically. Lastly, we summarize the various roles that CSB plays in the different steps of TC-NER, integrating the results of different studies and proposing a model as to how CSB facilitates TC-NER.

Expression and Purification of Recombinant Proteins Using the Baculovirus System.

This article describes how to analyze protein expression in cells infected with recombinant baculovirus on a small scale for optimizing protein production, how to maximize and scale up recombinant protein production, and how to purify recombinant proteins. © 2018 by John Wiley & Sons, Inc.

NAP1L1 accelerates activation and decreases pausing to enhance nucleosome remodeling by CSB.

Cockayne syndrome protein B (CSB) belongs to the SWI2/SNF2 ATP-dependent chromatin remodeler family, and CSB is the only ATP-dependent chromatin remodeler essential for transcription-coupled nucleotide excision DNA repair. CSB alone remodels nucleosomes ∼10-fold slower than the ACF remodeling complex. Strikingly, NAP1-like histone chaperones interact with CSB and greatly enhance CSB-mediated chromatin remodeling. While chromatin remodeling by CSB and NAP1-like proteins is crucial for efficient transcription-coupled DNA repair, the mechanism by which NAP1-like proteins enhance chromatin remodeling by CSB remains unknown. Here we studied CSB's DNA-binding and nucleosome-remodeling activities at the single molecule level in real time. We also determined how the NAP1L1 chaperone modulates these activities. We found that CSB interacts with DNA in two principle ways: by simple binding and a more complex association that involves gross DNA distortion. Remarkably, NAP1L1 suppresses both these interactions. Additionally, we demonstrate that nucleosome remodeling by CSB consists of three distinct phases: activation, translocation and pausing, similar to ACF. Importantly, we found that NAP1L1 promotes CSB-mediated remodeling by accelerating both activation and translocation. Additionally, NAP1L1 increases CSB processivity by decreasing the pausing probability during translocation. Our study, therefore, uncovers the different steps of CSB-mediated chromatin remodeling that can be regulated by NAP1L1.

Osthole protects sepsis-induced acute kidney injury via down-regulating NF-κB signal pathway.

BACKGROUND AND PURPOSE: As a natural coumarin derivative from the Cnidium monnieri(L)Cusson fruit, osthole consists of 7-methoxy-8-isopentenoxy-coumarin. The purpose of this research is to study the mechanism and effect of osthole on sepsis-induced acute kidney injury. EXPERIMENTAL APPROACH: The protective effect of osthole on mouse macrophage RAW 264.7 and HK-2 cells induced by LPS in vitro and on acute kidney injury model induced by sepsis and established by puncture and cecal ligation (CLP) in vivo were tested. KEY RESULTS: Osthole (20, 40 mg·kg-1) group can greatly attenuate the changes of the score and kidney histopathology damage and enhance the survival time of septic mice. After the CLP surgery, degrees of SCr and BUN related to kidney injury were upregulated. The concentrations of SCr and BUN can be greatly reduced by treatment with osthole. Furthermore, osthole could increase bacterial killing activity and phagocytic activities of macrophages impaired after CLP partly and attenuate blood bacterial counts and leukocyte infiltration markedly. Furthermore, osthole can suppress NF-κB signal pathway through the inhibition of the nuclear translocation by regulating phosphorylation of IκBα and IKKß and hinder the production of chemoattractant (MCP-1 and IL-8) and proinflammatory cytokines (TNF-α, IL-1ß and IL-6). CONCLUSION AND IMPLICATIONS: Mainly because of its immunomodulatory properties and anti-inflammatory activity, which might be closely associated with suppression of the stimulation of the NF-κB signal pathway, osthole has protective effect on sepsis-induced kidney injury. It can be seen from such evidence that osthole can be potentially applied in the treatment of acute kidney injury.

Paeonol protects endotoxin-induced acute kidney injury: potential mechanism of inhibiting TLR4-NF-κB signal pathway.

STUDY DESIGN AND METHODS: In order to determine the therapeutic effect and mechanism of paeonol on acute kidney injury induced by endotoxin, an acute kidney injury model was established by intraperitoneal administration of lipopolysaccharide in mice in vivo and on LPS-induced dendritic cells in vitro. Renal tissues were used for histologic examination. Concentrations of blood urea nitrogen and serum creatinine were detected, inflammatory cytokines were determined by ELISA. The relative proteins' expression of TLR4-NF-κB signal pathway was assessed by Western blot, the localization and expression of phospho-NF-κB p65 in kidney was monitored by immunohistochemistry. RESULTS: Treatment of paeonol successfully cuts histopathological scores and dilutes the concentrations of blood urea nitrogen and serum creatinine as index of renal injury severity. In addition, paeonol reduces pro-inflammatory cytokines and increases anti-inflammatory cytokines stimulated by LPS in a dose-dependent manner. Paeonol also inhibits the expression of phosphorylated NF-κB p65, IκBα and IKKß, and restrains NF-κB p65 DNA-binding activity. Paeonol treatment also attenuates the effects of LPS on dendritic cells, with significant inhibition of pro-inflammatory cytokines release, then TLR4 expression and NF-κB signal pathway have been suppressed. CONCLUSIONS: These results indicated that paeonol has protective effects on endotoxin-induced kidney injury. The mechanisms underlying such effects are associated with its successfully attenuate inflammatory and suppresses TLR4 and NF-κB signal pathway. Therefore, paeonol has great potential to be a novel and natural product agent for treating AKI or septic-AKI.

The CSB chromatin remodeler and CTCF architectural protein cooperate in response to oxidative stress.

Cockayne syndrome is a premature aging disease associated with numerous developmental and neurological abnormalities, and elevated levels of reactive oxygen species have been found in cells derived from Cockayne syndrome patients. The majority of Cockayne syndrome cases contain mutations in the ATP-dependent chromatin remodeler CSB; however, how CSB protects cells from oxidative stress remains largely unclear. Here, we demonstrate that oxidative stress alters the genomic occupancy of the CSB protein and increases CSB occupancy at promoters. Additionally, we found that the long-range chromatin-structure regulator CTCF plays a pivotal role in regulating sites of genomic CSB occupancy upon oxidative stress. We show that CSB directly interacts with CTCF in vitro and that oxidative stress enhances the CSB-CTCF interaction in cells. Reciprocally, we demonstrate that CSB facilitates CTCF-DNA interactions in vitro and regulates CTCF-chromatin interactions in oxidatively stressed cells. Together, our results indicate that CSB and CTCF can regulate each other's chromatin association, thereby modulating chromatin structure and coordinating gene expression in response to oxidative stress.