Gegen Qinlian decoction ameliorates TNBS-induced ulcerative colitis by regulating Th2/Th1 and Tregs/Th17 cells balance, inhibiting NLRP3 inflammasome activation and reshaping gut microbiota.

ETHNOPHARMACOLOGICAL RELEVANCE: Chinese herbal medicine Gegen Qinlian Decoction (GQD) has been clinically shown to be an effective treatment of ulcerative colitis (UC) in China. However, the underlying mechanism of GQD's anti-ulcerative colitis properties and its effect on gut microbiota still deserve further exploration. AIM OF THE STUDY: This study observed the regulatory effects of GQD on Th2/Th1 and Tregs/Th17 cells balance, the NOD-like receptor family pyrin domain containing 3 (NLRP3) infammasome and gut microbiota in TNBS-induced UC in BALB/c mice. MATERIALS AND METHODS: 61 main chemical compounds in the GQD were determined by UPLC-Q-TOF/MS. The UC BALB/c model was established by intrarectal administration of trinitrobenzene sulfonic acid (TNBS), and GQD was orally administered at low and high dosages of 2.96 and 11.83 g/kg/day, respectively. The anti-inflammatory effects of GQD for ulcerative colitis were evaluated by survival rate, body weight, disease activity index (DAI) score, colonic weight and index, spleen index, hematoxylin-eosin (HE) staining and histopathological scores. Flow cytometry was used to detect the percentage of CD4, Th1, Th2, Th17 and Tregs cells. The levels of Th1-/Th2-/Th17-/Tregs-related inflammatory cytokines and additional proinflammatory cytokines (IL-1ß, IL-18) were detected by CBA, ELISA, and RT-PCR. The expressions of GATA3, T-bet, NLRP3, Caspase-1, IL-Iß, Occludin and Zonula occludens-1 (ZO-1) on colon tissues were detected by Western blot and RT-PCR. Transcriptome sequencing was performed using colon tissue and 16S rRNA gene sequencing was performed on intestinal contents. Fecal microbiota transplantation (FMT) was employed to assess the contribution of intestinal microbiota and its correlation with CD4 T cells and the NLRP3 inflammasome. RESULTS: GQD increased the survival rate of TNBS-induced UC in BALB/c mice, and significantly improved their body weight, DAI score, colonic weight and index, spleen index, and histological characteristics. The intestinal barrier dysfunction was repaired after GQD administration through promoting the expression of tight junction proteins (Occludin and ZO-1). GQD restored the balance of Th2/Th1 and Tregs/Th17 cells immune response of colitis mice, primarily inhibiting the increase in Th2/Th1 ratio and their transcription factor production (GATA3 and T-bet). Morever, GQD changed the secretion of Th1-/Th2-/Th17-/Tregs-related cytokines (IL-2, IL-12, IL-5, IL-13, IL-6, IL-10, and IL-17A) and reduced the expressions of IL-1ß, IL-18. Transcriptome results suggested that GQD could also remodel the immune inflammatory response of colitis by inhibiting NOD-like receptor signaling pathway, and Western blot, immunohistochemistry and RT-PCR further revealed that GQD exerted anti-inflammatory effects by inhibiting the NLRP3 inflammasome, such as down-regulating the expression of NLRP3, Caspase-1 and IL-1ß. More interestingly, GQD regulated gut microbiota dysbiosis, suppressed the overgrowth of conditional pathogenic gut bacteria like Helicobacter, Proteobacteria, and Mucispirillum, while the probiotic gut microbiota, such as Lactobacillus, Muribaculaceae, Ruminiclostridium_6, Akkermansia, and Ruminococcaceae_unclassified were increased. We further confirmed that GQD-treated gut microbiota was sufficient to relieve TNBS-induced colitis by FMT, involving the modulation of Th2/Th1 and Tregs/Th17 balance, inhibition of NLRP3 inflammasome activation, and enhancement of colonic barrier function. CONCLUSIONS: GQD might alleviate TNBS-induced UC via regulating Th2/Th1 and Tregs/Th17 cells Balance, inhibiting NLRP3 inflammasome and reshaping gut microbiota, which may provide a novel strategy for patients with colitis.

Protective effect of the total flavonoids from Clinopodium chinense against LPS-induced mice endometritis by inhibiting NLRP3 inflammasome-mediated pyroptosis.

ETHNOPHARMACOLOGICAL RELEVANCE: Clinopodium chinense (Benth.) O. Kuntze (C. chinense) is a Chinese herbal medicine used in treating gynecological hemorrhagic diseases for hundreds of years. Flavonoids are one kind of the major components in C. chinense. The flavonoids of C. chinense (TFC) have a vital role in treating endometritis but the underlying therapeutic mechanisms of TFC against endometritis have been rarely reported. AIM OF THE STUDY: To elucidate the therapeutic effect and possible mechanisms of TFC against lipopolysaccharide (LPS)-induced endometritis in vivo and LPS-induced primary mouse endometrial epithelial cells (MEECs) injury in vitro. MATERIALS AND METHODS: The holistic phytochemicals of the TFC and TFC-contained serum were screened and identified using UPLC-Q-TOF-MS. The model of endometritis was established by intrauterine injection of LPS (5 mg/mL) into female BALB/c mice, and the model mice were treated with TFC for 7 days. The value of MPO was measured by Myeloperoxidase assay kit, the pathological changes in the endometrium were evaluated using H&E staining and transmission electron microscope (TEM), the secretions of IL-18, IL-1ß and TNF-α were determined by ELISA kits, the mRNA expressions of IL-18, IL-1ß and TNF-α were determined by RT-PCR assay, and the protein levels of TLR4, IKBα, p-IKBα, p65, p-p65, caspase-1, ASC, NLRP3 and GSDMD were measured by Western blot. Subsequently, MEECs were isolated from the uterus of pregnant female mice, injured by LPS for 24 h and incubated with the TFC-contained serum. Finally, cell viability, LDH release, hoechst 33342/PI staining, immunofluorescence staining, scanning electron microscope observation, ELISA assay, RT-PCR detection and Western blot analysis were carried out to further validate the therapeutic effect and the underlying mechanisms of TFC. RESULTS: A total of 6 compounds in the plasma of mice after being intragastric administrated of TFC were identified. The results in vivo showed that TFC significantly reduced MPO value and alleviated pathological injury of the endometrium. Furthermore, TFC significantly decreased the serum IL-18, IL-1ß and TNF-α levels, and the mRNA levels of IL-18, IL-1ß and TNF-α. TFC also inhibited the expressions of TLR4, p-IKBα, p-p65, caspase-1, ASC, NLRP3 and GSDMD. Besides, compared with the model group in MEECs cells, TFC-contained serum prevented pyroptosis, decreased the levels of IL-18 and IL-1ß, and inhibited the mRNA expressions of IL-18, IL-1ß and GSDMD. TFC-contained serum also reversed the activation of NLRP3 inflammasome caused by nigericin, and restrainted the translocation of NF-κB into nuclear. CONCLUSIONS: TFC protects mice endometritis from the injury of LPS via suppressing the activation of NLRP3 inflammasome and pyroptosis, the underlying mechanisms of which were related to restraining the TLR4/NF-κB/NLRP3 pathway activation.

Tibetan medicine Qi-Sai-Er-Sang-Dang-Song Decoction inhibits TNF-α-induced rheumatoid arthritis in human fibroblast-like synoviocytes via regulating NOTCH1/NF-κB/NLRP3 pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Qi-Sai-Er-Sang-Dang-Song Decoction (QSD, ཆུ་སེར་སེང་ལྡེང་སུམ་ཐང་།), a Tibetan classical herbal formula, is commonly used in Tibetan hospital preparation for the treatment of rheumatoid arthritis (RA). Its efficacy is to relieve inflammation, dispel cold, remove dampness, and alleviate pain. However, its anti-RA mechanism is still unclear. AIM OF THE STUDY: This study aimed to investigate the effect of QSD on rheumatoid arthritis and explore its anti-inflammatory mechanism against human fibroblast-like synoviocytes (HFLSs) by regulating the notch family of receptors (NOTCH1)/Nuclear factor-κB (NF-κB)/nucleotide-binding (NLRP3) pathway. MATERIALS AND METHODS: We used ultra-performance liquid chromatography coupled with Q-TOF mass spectrometry (UPLC-Q-TOF-MS) to identify the chemical composition of QSD. Then, HFLSs were exposed to drug-containing serum. The effect of QSD drug-containing serum on HFLS viability was detected using the cell counting kit-8 (CCK-8) assay. Next, we explored the anti-inflammatory effect of QSD using enzyme-linked immunosorbent assay (ELISA) for inflammatory factors, such as interleukin-18 (IL-18), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6). The expression of NOTCH-related proteins, a member of the NOTCH1, Cleaved NOTCH1, hairy and enhancer of split-1 (HES-1), NF-κB p65, NF-κB pp65, NLRP3, and delta-like 1 (DLL-1), was examined using western blotting. Furthermore, the relative mRNA expression levels of NOTCH1, NF-κB p65, NLRP3, DLL-1, and HES-1 were detected using real-time quantitative (RT-qPCR). To explore the mechanism underlying the anti-RA effect of QSD, we the used the NOTCH signaling pathway inhibitor LY411575 and transfection with a NOTCH1 siRNA. In addition, we employed immunofluorescence to determine the expression of HES-1 and NF-κB p65 in vitro. RESULT: Our results revealed that QSD ameliorated inflammation in HFLSs. Compared with the model group, the QSD drug-containing serum group had obviously down-regulated levels of IL-18, IL-1ß, and IL-6. Consistently, the CCK-8 results showed that the QSD drug-containing serum had no obvious toxicity towards HFLSs. Moreover, both LY411575 and siNOTCH1, QSD could reduce NOTCH1, NLRP3, and HES-1 protein expression levels, and LY411575 could significantly inhibit the expression levels of NF-κB p65, NF-κB pp65, and Cleaved NOTCH1 (p < 0.05). siNOTCH1 could also suppress the expression of DLL-1. The RT-qPCR results indicated that QSD could downregulate the relative mRNA expression levels of NOTCH1, NF-κB p65, NLRP3, DLL-1, and HES-1 in HFLSs (p < 0.05). In the immunofluorescence experiment, the fluorescence intensities of HES-1 and NF-κB p65 in HFLSs were found to decrease after exposure to QSD drug-containing serum (p < 0.05). Ultimately, 44 chemical components were detected in QSD using UPLC-Q-TOF-MS. CONCLUSION: This study reveals that the QSD can markedly ameliorate inflammation induced by TNF-α on HFLS. The effect of QSD on HFLS may be exerted by inhibition of the NOTCH1/NF-κB/NLRP3 signaling pathway.

Exploring the effect of Er miao San-containing serum on macrophage polarization through miR-33/NLRP3 pathway.

HEADINGS ETHNOPHARMACOLOGICAL RELEVANCE: Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease. Er miao San (EMS) has been shown to have good anti-inflammatory effects and is widely used in the clinical treatment of RA. However, the exact mechanism is not completely understood. AIM OF THE STUDY: The aim of this study was to explore that EMS-containing serum affects M1/M2 polarization of macrophages and may be mediated through the microRNA (miRNA)-33/NLRP3 pathway, thereby elucidating the molecular mechanism of EMS treatment of RA. MATERIALS AND METHODS: We screened for safe concentrations of EMS-containing serum by using CCK-8 measurement. RAW264.7 cells were cultured with lipopolysaccharide (LPS) (100 ng/mL) and interferon-γ (20 ng/mL) for 24 h to induce M1-type macrophages. Adenosine triphosphate (ATP) (5 mM) was added in the last 30 min to activate NLRP3. The content of miR-33 was detected by RT‒qPCR after transfection of the miRNA-33 mimic. The protein expression levels of NLRP3, ASC, caspase-1, Inducible Nitric Oxide Synthase (iNOS) and Arginase-1 (Arg-1) were detected by Western blot. The contents of IL-1ß, IL-10, TNF-α, TGF-ß and IL-18 in serum and cell supernatant were determined by ELISA. The fluorescence intensity of CD86 and CD206 was detected by immunofluorescence. RESULTS: The results showed that EMS-containing serum promoted the protein expression level of Arg-1 and the secretion levels of TGF-ß and IL-10, inhibited the levels of iNOS, IL-1ß and TNF-α, and regulated the balance of pro-inflammatory factors and anti-inflammatory factors. RT‒qPCR results showed that EMS-containing serum could reduce the level of miRNA-33. EMS-containing serum could reduce the expression of NLRP3 inflammasome-related proteins and downregulate the expression levels of IL-1ß and IL-18. These results suggest that EMS exerts its effect on macrophage polarization through the miRNA-33/NLRP3 pathway. CONCLUSION: EMS-containing serum inhibits the activation of the NLRP3 inflammasome by downregulating miRNA-33, thus preventing the polarization of M1-type macrophages.

Effect of Berberine on Activation of TLR4-NFκB Signaling Pathway and NLRP3 Inflammasome in Patients with Gout.

OBJECTIVE: To determine the effects of berberine (BBR) on the activation of toll-like receptor 4 (TLR4), nuclear factor (NF)κB (NF-κB) signaling and NLRP3 inflammasome in patients with gout. METHODS: Peripheral blood mononuclear cells (PBMCs) were obtained from 24 acute (AP) and 41 non-acute (NAP) phases of primary gout patients, respectively, as well as 30 healthy controls (HC). TLR4, NF-κB (p65), NLRP3, apoptosis-associated specklike protein containing a CARD (PYCARD), cysteinyl aspartate specific proteinase-1 (CASP1), and interleukin-1ß (IL-1ß) mRNA expression levels in PBMCs were measured by quantitative reverse transcriptase polymerase chain reaction. The protein levels of TLR4, myeloid differentiation factor 88 (MyD88), NF-κB (p50/65), inhibitor of kappa B kinase α/ß (IKKα/ß), NF-κB inhibitor α (IKBα), phospho-IKKα/ß (p-IKKα/ß), NLRP3, PYCARD, and CASP1 were monitored by Western blotting. Serum IL-1ß protein level was measured using enzyme-linked immunosorbent assay (ELISA). In addition, PBMCs from HC and macrophages derived from a spontaneously immortalized monocyte-like cell line (THP-1) were stimulated using monosodium urate (MSU, 100 µg/mL), 0.1% dimethyl sulfoxide, 25 µmol/L BBR, and 10, 25, and 50 µmol/L BBR+100 µg/mL MSU for different time periods. The protein levels of IL-1ß and IL-18 in cell culture supernatants was measured by ELISA, and the protein expressions of TLR4, MyD88, NF-κB (p50/p65), IKKα/ß, I κBß, p-IKKα/ß, NLRP3, PYCARD, and CASP1 in macrophages were analyzed by Western blotting. RESULTS: (1) TLR4, NF-κB (p65), PYCARD, CASP1, and IL-1ß mRNA levels in PBMCs were significantly higher in the AP group than in the HC group (P<0.05). The NLRP3 mRNA expression levels in PBMCs were found to be significantly lower in the AP and NAP groups than in the HC group (P<0.05, P<0.01). (2) The protein levels of TLR4, IKKß, MyD88, NF-κB, p-IKKα/ß, PYCARD, and CASP1 in PBMCs were significantly higher, and those of IκBα, IKKα, and NLRP3 were found to be significantly lower in the AP group than in the HC group (P<0.05 or P<0.01). (3) The serum IL-1ß protein levels were significantly higher in the AP and NAP groups than in the HC group (P<0.01). (4) The IL-1ß protein level was significantly lower in the culture supernatants of the PBMCs stimulated with MSU for 3 and 6 h in the 25 and 50 µmoL/L BBR groups compared with that in the MSU group (P<0.01). (5) The protein levels of IL-1ß and IL-18 were also significantly lower in the culture supernatants of macrophages stimulated with MSU for 3 and 6 h in BBR groups compared with those in the MSU group (P<0.01). (6) The protein levels of TLR4, MyD88, NF-κB (p50, p65, p105), IKKα/ß, p-IκBα, p-IKKα/ß, PYCARD, and CASP1 were significantly differed between the macrophages stimulated with MSU for 0.5 and 6 h in BBR groups compared with those in the MSU group (P<0.05 or P<0.01). CONCLUSIONS: Activation of TLR4-NFκB signaling and NLRP3 inflammasome by MSU crystals drives the progression of gout inflammation. BBR ameliorates gouty inflammation, which is mechanistically associated with its regulation of TLR4-NF-κB signaling and NLRP3 inflammasome expression.

Xianglian Pill attenuates ulcerative colitis through TLR4/MyD88/NF-κB signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Xianglian Pill (XLP) is a classical Chinese medicine prescription applied for controlling ulcerative colitis (UC). Whereas, the underlying mechanism remains unclear. AIM OF THE STUDY: The present work was aimed to investigate the mechanism of XLP in dextran sulfate sodium (DSS)-induced UC via the Toll Like Receptor 4 (TLR4)/Myeloid Differentiation factor 88 (MyD88)/Nuclear Factor kappa-B (NF-κB) signaling in mice. MATERIALS AND METHODS: The major components of XLP were detected by high-performance liquid chromatography-diode array detection (HPLC-DAD). The ulcerative colitis model was induced by DSS in mice. 5-Amino Salicylic Acid (5-ASA) group and XLP group were intragastrically treated. Disease activity index (DAI) and colon length were monitored and hematoxylin-eosin (HE) staining was conducted. Gasdermin D (GSDMD)-N and TLR4 expressions in colon tissues were visualized by immunofluorescence. TLR4 mRNA was measured by Real Time Quantitative PCR (RT-qPCR). The expressions of NOD-like receptor thermal protein domain associated protein 3 (NLRP3), active-caspase-1, GSDMD-N, TLR4, MYD88, NF-κB, p-NF-κB, and the ubiquitination of TLR4 in colon tissues were detected by Western blot. Myeloperoxidase (MPO) enzyme activity was examined and serum inflammatory factors Interleukin (IL)-1ß, IL-6, Tumor Necrosis Factor-α (TNF-α), and IL-18 were determined by Enzyme-linked Immunosorbent Assay (ELISA). TLR4-/- mice were applied for verifying the mechanism of XLP attenuated DSS symptoms. RESULTS: The XLP treatment extended colon length, reduced DAI, and attenuated histopathological alteration in DSS-induced mice. XLP administration suppressed MPO activity and reduced the content of IL-1ß, IL-6, TNF-α and IL-18 in serum. XLP also inhibited the expression levels of GSDMD-N, TLR4, NLRP3, active-caspase-1, MyD88, p-NF-κB/NF-κB in colon tissues of DSS-induced mice. TLR4-/- mice proved that TLR4 was involved in XLP-mediated beneficial effect on DSS-induced ulcerative colitis. CONCLUSIONS: XLP might treat ulcerative colitis by regulating the TLR4/MyD88/NF-κB signaling pathway.

Effects of n-butanol extract of Pulsatilla decoction on the NLRP3 inflammasome in macrophages infected with Candida albicans.

ETHNOPHARMACOLOGICAL RELEVANCE: Pulsatilla decoction is a traditional Chinese medicine from Shang Han Lun that has been reported to have therapeutic efficacy in vulvovaginal candidiasis (VVC), and is a growth inhibitor of Candida albicans (C. albicans) in vitro, the causative agent of VVC. AIM OF THE STUDY: In previous studies, Pulsatilla decoction has shown therapeutic benefits for VVC. With further chemical extraction of the decoction, the n-butanol extract (of Pulsatilla decoction; BEPD) was most effective against C. albicans and therapeutic for VVC. The mechanism, however, has not been elucidated. The regulation of NOD-like receptor protein 3 (NLRP3) inflammasome has recently been demonstrated as a critical component of the inflammasome complex that initiates the vaginal inflammatory response. Therefore, the effect of BEPD on NLRP3 associated with VVC was investigated. MATERIALS AND METHODS: Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was used for detecting the principal compounds of BEPD (Anemoside B4, Esculin, esculetin, Epiberberine, Berberine, Jatrorrhizine and Phellodendrine). BEPD-containing serum is prepared by intragastric administration of BEPD (4.6875 g/kg for seven days) in rats. PMA-induced THP-1 cells were challenged with C. albicans. The expression of CD68 to identify macrophages was examined by flow cytometry, the viability of THP-1 cells were assessed by CCK8 assay, the release of lactate dehydrogenase (LDH) was detected by LDH kit, and the secretion levels of IL-1ß and IL-18 were evaluated through enzyme-linked immunosorbent assay (ELISA), the levels of NLRP3 were quantified by immunofluorescence, the levels of reactive oxygen species (ROS) were measured by ROS kit, and the expression of Dectin-1, Syk, TLR2, TLR4, MyD88, NF-κB, NLRP3, Caspase-1, and ASC proteins were detected by Western blot. RESULTS: After administration of BEPD-containing serum, the levels of IL-1ß, IL-18 and LDH released from macrophages were reduced in the BEPD-containing serum group compared to the model group. In addition, BEPD-containing serum inhibited the expression of ROS in macrophages, suppressed the expression of NLRP3 and inhibited the expression of TLRs/MyD88 and Dectin-1/Syk signaling pathway-related proteins. CONCLUSIONS: BEPD suppressed the NLRP3 inflammasome and related signaling pathways in macrophages infected with C. albicans in vitro, thereby providing insight into the mechanism of BEPD action on VVC.

Qing-Chang-Hua-Shi granule ameliorates DSS-induced colitis by activating NLRP6 signaling and regulating Th17/Treg balance.

BACKGROUND: Chinese herbal medicine Qing-Chang-Hua-Shi granule (QCHS) is widely used to treat ulcerative colitis in China. However, the molecular mechanisms of QCHS remains largely unknown. PURPOSE: To assess the therapeutic effects of QCHS on colitis and to reveal its mechanisms of action. METHODS: The main components of QCHS were identified using a UHPLC-QTOF-MS method and the efficacy of QCHS was evaluated using an DSS-induced mice model. The inflammatory responses and mucosal integrity in colon were comprehensively assessed. Flow cytometry was used to analysis the proportion of Th17 and Treg cells. Detect the signal transduction of the NOD-like receptor family pyrin domain containing 6 (NLRP6) both in vitro and in vivo. Furthermore, siNLRP6 transfection was used to validate the functional targets of QCHS. RESULTS: QCHS treatment significantly alleviated colitis in mice by improving symptoms and pathological damage. Moreover, QCHS treatment suppressed the inflammatory response and preserved the integrity of colon tissue. Most importantly, QCHS balanced the Th17/Treg response of UC mice. Mechanistically, by activating NLRP6 inflammasome pathway, QCHS regulated the maturation of interleukin (IL)-1ß and IL-18 to affect inflammation and drive Th17 cell differentiation. CONCLUSIONS: The effect of QCHS on UC mice is dose-dependent, with high-dose QCHS being superior to 5-Aminosalicylic acid (200 mg/kg/day). QCHS acts through the NLRP6 signaling pathway to modulate Th17/Treg balance, resulting in the protective effects against colitis. This study investigated the relevant pharmacological mechanisms of QCHS, providing further evidence for the application of QCHS in UC treatment.

Anti-inflammatory potential of stevia residue extract against uric acid-associated renal injury in mice.

Abnormal uric acid level result in the development of hyperuricemia and hallmark of various diseases, including renal injury, gout, cardiovascular disorders, and non-alcoholic fatty liver. This study was designed to explore the anti-inflammatory potential of stevia residue extract (STR) against hyperuricemia-associated renal injury in mice. The results revealed that STR at dosages of 150 and 300 mg/kg bw and allopurinol markedly modulated serum uric acid, blood urea nitrogen, and creatinine in hyperuricemic mice. Serum and renal cytokine levels (IL-18, IL-6, IL-1Β, and TNF-α) were also restored by STR treatments. Furthermore, mRNA and immunohistochemistry (IHC) analysis revealed that STR ameliorates UA (uric acid)-associated renal inflammation, fibrosis, and EMT (epithelial-mesenchymal transition) via MMPS (matrix metalloproteinases), inhibiting NF-κB/NLRP3 activation by the AMPK/SIRT1 pathway and modulating the JAK2-STAT3 and Nrf2 signaling pathways. In summary, the present study provided experimental evidence that STR is an ideal candidate for the treatment of hyperuricemia-mediated renal inflammation. PRACTICAL APPLICATIONS: The higher uric acid results in hyperuricemia and gout. The available options for the treatment of hyperuricemia and gout are the use of allopurinol, and colchicine drugs, etc. These drugs possess several undesirable side effect. The polyphenolic compounds are abundantly present in plants, for example, stevia residue extract (STR) exert a positive effect on human health. From this study results, we can recommend that polyphenolic compounds enrich STR could be applied to develop treatment options for the treatment of hyperuricemia and gout.

Uranium induces kidney cells pyroptosis in culture involved in ROS/NLRP3/caspase-1 signaling.

Pyroptosis is an exceptional mode of inflammation and programmed cell death involved in inflammasomes and Caspase-1 activation and inflammatory cytokines releasing. Our goal is to explore whether uranium (U)-intoxication could induce NRK-52E cells pyroptosis in vitro and its underlying molecular mechanism. Rat NRK-52E cells were intoxicated with U concentrations (400-500 µM) for 24 h. The results indicate that the cells showed characteristic features of pyroptosis, which were identified through augmented NLRP3 and cleaved Caspase-1 proteins expression, GSDMD mRNA level, mature interleukin IL-18 and IL-1ß contents, LDH leakage, and the number of double-positive cells. But, administration of glycine (an inhibitor of pyroptosis) effectively attenuated U-induced pyroptosis, LDH releasing and cytotoxicity. Pretreatment of CRID3 (an inhibitor of NLRP3 inflammasome) evidently abrogated NLRP3 and cleaved Caspase-1 proteins and GSDMD mRNA expression which all were up-regulated by U exposure. Simultaneously, CRID3 significantly reversed U-increased pyroptosis rate and active interleukin IL-18 and IL-1ß contents. NAC application (an ROS scavenger) effectively decreased U-increased ROS content and NLRP3 expression and restored U-induced pyroptosis. Taken together, our results suggest that U-treatment can trigger NRK-52E cells pyroptosis which is involvement of ROS/NLRP3/Caspase-1 pathway. Targeting ROS/NLRP3/Caspase-1-mediated pyroptosis may be a novel approach for attenuating U nephrotoxicity.

Electroacupuncture Prevents the Depression-Like Behavior by Inhibiting the NF-κB/NLRP3 Inflammatory Pathway in Hippocampus of Mice Subjected to Chronic Mild Stress.

BACKGROUND: The precise physiological mechanisms of acupuncture in the treatment of depression are still unknown. This study aimed to observe the effects of electroacupuncture (EA) on depression-like behavior of mouse in chronic mild stress (CMS) model and explore the underlying mechanism. METHODS: The depression model was established by using CMS method for 6 weeks. After the third week of the CMS paradigm, EA treatment was performed daily for 15 min over a period of 3 weeks. The antidepressant-like effects of EA were evaluated using the sucrose preference test and the forced swimming test (FST). The protein levels of the nuclear factor-kappa B (NF-κB), p-NF-κB, inhibitor of NF-κB, p-IκBα, NOD-like receptor protein 3, interleukin (IL)-6, IL-1ß, IL-18, and tumor necrosis factor-α (TNF-α) in hippocampus of mice were detected. RESULTS: Sucrose preference was decreased after 6 weeks of CMS and the effects of CMS was reversed by EA. CMS increased immobility time and decreased latency to the first immobility in the FST test, but these effects were reversed by EA. CMS-induced nuclear entry of NF-κB (nuclear/cytoplasmic ratio of NF-κB) with an increase in protein levels of p-NF-κB and p-IκBα in the hippocampus. The CMS also increased NLRP3 levels in the hippocampus. However, these effects were reversed by EA. In addition, the levels of IL-6, IL-1ß, IL-18, and TNF-α in the hippocampus were increased by CMS, and these effects of stress were reversed by EA. CONCLUSION: EA prevented CMS-induced depressive-like behaviors by inhibiting NF-κB/NLRP3 inflammatory pathway.

Short-Term Adjuvant Therapy with Terminalia arjuna Attenuates Ongoing Inflammation and Immune Imbalance in Patients with Stable Coronary Artery Disease: In Vitro and In Vivo Evidence.

The present study evaluated the cardioprotective effects of Terminalia arjuna on classical and immuno-inflammatory markers in coronary artery disease (CAD) as an adjuvant therapy. One hundred sixteen patients with stable CAD were administered placebo/T. arjuna (500 mg twice a day) along with medications in a randomized, double-blind clinical trial. To understand the specificity and efficacy of T. arjuna, we evaluated its effect through microarray and in silico analysis in few representative samples. Data was further validated via real-time PCR (n = 50) each at baseline, 3 months, and 6 months, respectively. rIL-18 cytokine was used to induce inflammation in vitro to compare its effects with atorvastatin. T. arjuna significantly down-regulated TG, VLDL-C, and immuno-inflammatory markers in stable CAD versus placebo-treated subjects. Microarray and pathway analysis of a few samples from T. arjuna/placebo-treated groups and real-time PCR validation further confirmed our observations. Our data demonstrate the anti-inflammatory and immunomodulatory effects of T. arjuna that may attenuate ongoing inflammation and immune imbalance in medicated CAD subjects.

Interleukin-18-induced human coronary artery smooth muscle cell migration is dependent on NF-kappaB- and AP-1-mediated matrix metalloproteinase-9 expression and is inhibited by atorvastatin.

The proliferation and migration of arterial smooth muscle cells (SMCs) are key events in the vascular restenosis that frequently follows angioplasty. Furthermore, SMC migration and neointimal hyperplasia are promoted by degradation of the extracellular matrix by matrix metalloproteinases (MMPs). Because we demonstrated previously that the proinflammatory and proatherogenic cytokine interleukin-18 (IL-18) stimulates SMC proliferation (Chandrasekar, B., Mummidi, S., Valente, A. J., Patel, D. N., Bailey, S. R., Freeman, G. L., Hatano, M., Tokuhisa, T., and Jensen, L. E. (2005) J. Biol. Chem. 280, 26263-26277), we investigated whether IL-18 induces SMC migration in an MMP-dependent manner and whether the 3-hydroxy-3-methylglutaryl-CoA reductase inhibitor atorvastatin can inhibit this response. IL-18 treatment increased both mRNA and protein expression of MMP9 in human coronary artery SMCs. Gel shift, enzyme-linked immunosorbent, and chromatin immunoprecipitation assays revealed a strong induction of IL-18-mediated AP-1 (c-Fos, c-Jun, and Fra-1) and NF-kappaB (p50 and p65) activation and stimulation of MMP9 promoter-dependent reporter gene activity in an AP-1- and NF-kappaB-dependent manner. Ectopic expression of p65, c-Fos, c-Jun, and Fra-1 induced MMP9 promoter activity. Specific antisense or small interfering RNA reagents for these transcription factors reduced IL-18-mediated MMP9 transcription. Furthermore, IL-18 stimulated SMC migration in an MMP9-dependent manner. Atorvastatin effectively suppressed IL-18-mediated AP-1 and NF-kappaB activation, MMP9 expression, and SMC migration. Together, our results indicate for the first time that the proatherogenic cytokine IL-18 induces human coronary artery SMC migration in an MMP9-dependent manner. Atorvastatin inhibits IL-18-mediated aortic SMC migration and has therapeutic potential for attenuating the progression of atherosclerosis and restenosis.

Interleukins 18 and 21: biology, mechanisms of action, toxicity, and clinical activity.

Interleukins 18 and 21 have been described, and the effect of each upon immune response and experimental tumors in animals has been the subject of much recent work. Both interleukins have shown antitumor effects in animals, which in some models are striking for their duration, specificity, and ability to protect against rechallenge with the same tumor. These characteristics suggest immunologic involvement in the antitumor response, and several papers suggest involvement of both innate and adaptive immune mechanisms. Recent early phase I clinical trials in human cancer patients have demonstrated evidence of clinical response. This review discusses the biology, preclinical animal tumor model data, and early clinical trial findings.

Cys74 and Cys163 are necessary for IL-18 to elicit IFN-gamma production from peripheral blood lymphoid mononuclear cells.

There are four cysteines (Cys74, Cys104, Cys112 and Cys163) in mature human IL-18 (hIL-18). These cysteines are highly conserved in IL-18s of 11 species cloned so far, suggesting that one or more of the cysteines may be important for hIL-18 function. In this study, each cysteine residue was individually replaced with serine by site-directed mutagenesis. The wild type and mutant IL-18s were expressed in Escherichia coli and renatured by two renaturing methods. The purified wild type and mutant rhIL-18s were assayed for their capacity of inducing IFN-gamma and activating NF-kappaB from ConA-stimulated PBMC. DNA binding activity of NF-kappaB was performed by electrophoretic mobility-shift analysis. Our results showed that the mutant rhIL-18C74S and C163S induced much less amount of IFN-gamma from PBMC and the decrement of NF-kappaB DNA binding activity was also observed from C74S and C163S treated PBMC. These results indicate that functional hIL-18 has an absolute requirement for residues Cys74 and Cys163.

Implication of interleukin 18 in production of matrix metalloproteinases in articular chondrocytes in arthritis: direct effect on chondrocytes may not be pivotal.

OBJECTIVE: To clarify the effect of interleukin (IL) 18 on cartilage degeneration by studying the profile of IL18 receptor (IL18R) on chondrocytes and the direct effect of IL18 on production of matrix metalloproteinases (MMPs), aggrecanases, and tissue inhibitors of metalloproteinases (TIMPs) in articular chondrocytes. METHODS: Monolayer cultured human articular chondrocytes were isolated from non-arthritic subjects and patients with rheumatoid arthritis or osteoarthritis. Gene expression of IL18, IL18Ralpha, IL18Rbeta, MMPs, and aggrecanases was detected by RT-PCR. Protein levels of IL18Ralpha were analysed by flow cytometry. Protein levels of IL18, MMPs, and TIMPs were measured by ELISA. Aggrecanase-2 mRNA expression was quantitatively analysed by real time RT-PCR. Protein levels of signalling molecules were assayed by western blotting. RESULTS: IL18 mRNA was constitutively expressed in chondrocytes, and was enhanced by IL1beta stimulation. Flow cytometric analysis showed that IL1beta, tumour necrosis factor alpha, and IL18 up regulated IL18Ralpha expression levels. The level of IL18Rbeta mRNA was much lower than that of IL18Ralpha, and was slightly up regulated by IL1beta. In chondrocytes responding to IL18, IL18 (1-100 ng/ml) slightly increased the production of MMP-1, MMP-3, and MMP-13, which was blocked by NF-kappaB inhibitor and p38 mitogen activated protein kinase inhibitor. IL18 up regulated mRNA expression of aggrecanase-2, but not aggrecanase-1. IL18 also slightly stimulated TIMP-1 production?through extracellular signal regulated kinase activation. CONCLUSION: IL18 induces production of MMPs from chondrocytes in inflammatory arthritis. Although the direct effect of IL18 on chondrocytes may not be pivotal for the induction of cartilage degeneration, IL18 seems to play some part in the degradation of articular cartilage in arthritis.

Differences in signaling pathways by IL-1beta and IL-18.

IL-1 and IL-18 are members of the IL-1 family of ligands, and their receptors are members of the IL-1 receptor family. Although several biological properties overlap for these cytokines, differences exist. IL-18 uniquely induces IFN-gamma from T lymphocytes and natural killer cells but does not cause fever, whereas fever is a prominent characteristic of IL-1 in humans and animals. In the present study, human epithelial cells were stably transfected with the IL-18 receptor beta chain and responded to IL-18 with increased production of IL-1alpha, IL-6, and IL-8. Five minutes after exposure to either cytokine, phosphorylation of mitogen activated protein kinase (MAPK) p38 was present; specific inhibition of p38 MAPK reduced IL-18 activity to background levels. Whereas IL-1beta induced the expression of the NF-kappaB-reporter gene and was suppressed by competitive inhibition of NF-kappaB binding, IL-18 responses were weak or absent. In contrast to IL-1beta, IL-18 also did not activate degradation of the NF-kappaB inhibitor. After 4 h, both cytokines induced comparable levels of mRNA for the chemokine IL-8 but, in the same cells, steady-state levels of cyclooxygenase (COX)-2 mRNA were high after IL-1beta but low or absent after IL-18. After 30 h, IL-18-induced COX-2 appeared in part to be IL-1 dependent. Similarly, low levels of prostaglandin E2 were measured in IL-18-stimulated A549 cells and freshly obtained primary human monocytes and mouse macrophages. We conclude that in epithelial cells, IL-18 signal transduction is primarily via the MAPK p38 pathway rather than NF-kappaB, which may explain the absence of COX-2 and the failure of IL-18 to cause fever.

Nitric oxide synthase inhibitor and IL-18 enhance the anti-tumor immune response of rats carrying an intrahepatic colon carcinoma.

The role of nitric oxide (NO) produced by adherent spleen cells in the systemic immunosuppression developing in tumor-bearing hosts was investigated. After therapeutic immunization of rats carrying an intrahepatic colon carcinoma, H1D2, the spleen cell antitumor immune responsiveness was analyzed. Compared to parallel immunized tumor-free rats, tumor-bearing rats (TB rats) had a greatly reduced proliferative T-cell response to wild-type tumor stimulator cells. The TB rats had a depressed proliferative response to anti-CD3 and to the superantigen SEA. TB rats with small tumors had a stronger response to IL-18-producing H1D2 stimulator cells than to wild type H1D2 cells. This was not the case with TB rats carrying larger tumors. Also the IFN-gamma production and cytotoxicity against the wild-type tumor cells and the NK sensitive YAC cells were depressed in spleen cells of TB rats after 5-day restimulation with wild-type tumor cells. A part of this immunosuppression was mediated by adherent spleen cells, mostly consisting of macrophages. An important mode of action appears to involve their production of an enhanced level of nitric oxide, since the competitive nitric oxide synthase (NOS) inhibitor L-NAME could partially counteract the suppression in vitro. We conclude that NOS inhibitors in combination with immunostimulatory cytokines, such as IL-18, could be useful tools to enhance anti-tumor immune responses in TB rats and therefore to increase the efficiency of immunotherapies.

Canine interleukin-18 induces apoptosis and enhances Fas ligand mRNA expression in a canine carcinoma cell line.

Recombinant canine interleukin-18 (IL-18) induced apoptosis in vitro in a canine cancer cell line derived from canine mammary gland tumor tissue as determined by electrophoretical DNA separation and flow cytometry after propidium iodine staining. To investigate Fas ligand (FasL) expression on the cell line, we cloned the partial sequence of canine Fas Ligand (FasL) cDNA from canine lymphocytes. We found, by RT-PCR analyses, that the cell line expressed FasL mRNA and it was augmented by treatment with canine IL-18 and further enhanced by addition of canine IL-12. Treatment with recombinant canine IL-18 resulted in complete regression of the cell line transplanted into scid mice. This anti-tumor activity was not blocked by anti-mouse IFN-gamma and anti-asialo GM1 antibody, suggesting that the tumor regression was not dependent on IFN-gamma or NK cells of the host. Because there is no cross-reactivity of canine IL-18 with mouse host cells, these results suggested that canine IL-18 may be able to directly kill the breast cancer cells by inducing apoptosis. Canine IL-18 should prove useful as an anti-cancer agent.