A2AR regulate inflammation through PKA/NF-κB signaling pathways in intervertebral disc degeneration.

BACKGROUND: Reduction of inflammatory damage and inhibition of nucleus pulposus (NP) apoptosis are considered to be the main effective therapy idea to reverse the intervertebral disc degeneration (IDD) and alleviate the chronic low back pain. The adenosine A2A receptor (A2AR), as a member of G protein-coupled receptor families, plays an important role in the anti-inflammation and relieving pain. So far, the impact of A2AR on IDD therapy is unclear. The aim of this study was to explore the role of Adenosine A2A receptor (A2AR) in the intervertebral disc degeneration (IDD) and clarify potential mechanism. MATERIALS AND METHODS: IL-1ß and acupuncture was used to establish IDD model rats. A2AR agonist CGS-21680 and A2AR antagonist SCH442416 were used to investigate the therapeutical effects for IDD. Histological examination, western blotting analysis and RT-PCR were employed to evaluate the the association between A2AR and cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) pathway. RESULTS: A2AR activity of the intervertebral disc tissues was up-regulated in feedback way, and cAMP, PKA and CREB expression were also increased. But in general, IL-1ß-induced IDD promoted the significant up-regulation the expression of inflammatory factors. The nucleus pulposus (NP) inflammation was exacerbated in result of MMP3 and Col-II decline through activating NF-κB signaling pathway. A2AR agonist CGS-21680 exhibited a disc protective effect through significantly increasing A2AR activity, then further activated cAMP/PKA signaling pathway with attenuating the release of TNF-α and IL-6 via down-regulating NF-κB. In contrast, SCH442416 inhibited A2AR activation, consistent with lower expression levels of cAMP and PKA, further leading to the acceleration of IDD. CONCLUSIONS: The activation of A2AR can prevent inflammatory responses and mitigates degradation of IDD thus suggest a potential novel therapeutic strategy of IDD.

E3 ubiquitin ligase RNF128 attenuates colitis and colorectal tumorigenesis by triggering the degradation of IL-6 receptors.

INTRODUCTION: Intestinal immune dysregulation is strongly linked to the occurrence and formation of tumors. RING finger protein 128 (RNF128) has been identified to play distinct immunoregulatory functions in innate and adaptive systems. However, the physiological roles of RNF128 in intestinal inflammatory conditions such as colitis and colorectal cancer (CRC) remain controversial. OBJECTIVES: To elucidate the function and mechanism of RNF128 in colitis and CRC. METHODS: Animal models of dextran sodium sulfate (DSS)-induced colitis and azoxymethane (AOM)/DSS-induced CRC were established in WT and Rnf128-deficient mice and evaluated by histopathology. Co-immunoprecipitation and ubiquitination analyses were employed to investigate the role of RNF128 in IL-6-STAT3 signaling. RESULTS: RNF128 was significantly downregulated in clinical CRC tissues compared with paired peritumoral tissues. Rnf128-deficient mice were hypersusceptible to both colitis induced by DSS and CRC induced by AOM/DSS or APC mutation. Loss of RNF128 promoted the proliferation of CRC cells and STAT3 activation during the early transformative stage of carcinogenesis in vivo and in vitro when stimulated by IL-6. Mechanistically, RNF128 interacted with the IL-6 receptor α subunit (IL-6Rα) and membrane glycoprotein gp130 and mediated their lysosomal degradation in ligase activity-dependent manner. Through a series of point mutations in the IL-6 receptor, we identified that RNF128 promoted K48-linked polyubiquitination of IL-6Rα at K398/K401 and gp130 at K718/K816/K866. Additionally, blocking STAT3 activation effectively eradicated the inflammatory damage of Rnf128-deficient mice during the transformative stage of carcinogenesis. CONCLUSION: RNF128 attenuates colitis and colorectal tumorigenesis by inhibiting IL-6-STAT3 signaling, which sheds novel insights into the modulation of IL-6 receptors and the inflammation-to-cancer transition.

Jiawei Bai-Hu-decoction ameliorated heat stroke-induced brain injury by inhibiting TLR4/NF-κB signal and mitophagy of glial cell.

ETHNOPHARMACOLOGICAL RELEVANCE: Jiawei Bai-Hu-Decoction (JWBHD), a prescription formulated with seven traditional Chinese medicinal material has demonstrated clinical efficacy in mitigating brain injury among heat stroke (HS) patients. AIM OF THE STUDY: This study aimed to evaluate the therapeutic efficacy of JWBHD on rat model of HS and to explore its therapeutic mechanisms by integrating network pharmacology and pharmacodynamic methodologies, which major components were analyzed by using UPLC-MS/MS. MATERIALS AND METHODS: The network pharmacology analysis was firstly conducted to predict the potential active ingredients and therapeutic targets of JWBHD. The anti-HS effectiveness of JWBHD was then evaluated on rats experienced HS. Rat brain tissues were harvested for a comprehensive array of experiments, including Western blot, PCR, H&E staining, Nissl staining, ELISA, transmission electron microscope, flow cytometry and immunofluorescence to validate the protective effects of JWBHD against HS-induced brain damage. Furthermore, the inhibitory effects of JWBHD on TLR4/NF-κB signal and mitophagy of glial were further verified on HS-challenged F98 cell line. Finally, the chemical compositions of the water extract of JWBHD were analyzed by using UPLC-MS/MS. RESULTS: Network pharmacology has identified fifty core targets and numerous HS-related signaling pathways as potential therapeutic targets of JWBHD. Analysis of protein-protein interaction (PPI) and GO suggests that JWBHD may suppress HS-induced inflammatory signals. In experiments conducted on HS-rats, JWBHD significantly reduced the core temperature, restored blood pressure and alleviated neurological defect. Furthermore, JWBHD downregulated the counts of white blood cells and monocytes, decreased the levels of inflammatory cytokines such as IL-1ß, IL-6 and TNF-α in peripheral blood, and suppressed the expression of TLR4 and NF-κB in the cerebral cortex of HS-rats. Besides, JWBHD inhibited the apoptosis of cortical cells and mitigated the damage to the cerebral cortex in HS group. Conversely, overactive mitophagy was observed in the cerebral cortex of HS-rats. However, JWBHD restored the mitochondrial membrane potential and downregulated expressions of mitophagic proteins including Pink1, Parkin, LC3B and Tom20. JWBHD reduced the co-localization of Pink1 and GFAP, a specific marker of astrocytes in the cerebral cortex of HS-rats. In addition, the inhibitory effect of JWBHD on TLR4/NF-κB signaling and overactive mitophagy were further confirmed in F98 cells. Finally, UPLC-MS/MS analysis showed that the main components of JWBHD include isoliquiritigenin, liquiritin, dipotassium glycyrrhizinate, ginsenoside Rb1, ginsenoside Re, etc. CONCLUSIONS: JWBHD protected rats from HS and prevented HS-induced damage in the cerebral cortex by suppressing TLR4/NF-κB signaling and mitophagy of glial.

Protective effect of feed additive ferulic acid on respiratory depression and oxidation imbalance of carp induced by pesticide difenoconazole via ROS/NF-κB/NLRP3 axis.

Difenoconazole (DFZ), classified as a "low-toxicity pesticide," has seen widespread application in recent years. Nevertheless, the non-target toxicity of the substance, particularly towards aquatic creatures, has generated considerable apprehension. The anti-inflammatory and antioxidant effects of Ferulic Acid (FA) have attracted considerable study in this particular setting. This study established a chronic exposure model to DFZ and investigated the protective effects of FA on chronic respiratory inhibition leading to gill damage in freshwater carp. Histological analyses via HE staining indicated that FA effectively alleviated gill tissue damage induced by chronic DFZ exposure. The qRT-PCR results showed that the addition of FA reduced the expression of IL-1ß, IL-6 and TNF-α while boosting the expression of IL-10 and TGF-ß1. Biochemical analyses and DHE staining revealed that FA reduced MDA levels and increased CAT and GSH activities, along with T-AOC, decreased ROS accumulation in response to chronic DFZ exposure. The results obtained from Western blotting analysis demonstrated that the addition of FA effectively suppressed the activation of the NF-κB signalling pathway and the NLRP3 inflammasome pathway in the gills subjected to prolonged exposure to DFZ. In summary, FA ameliorated gill tissue inflammation and blocked ROS accumulation in carp exposed to chronic DFZ, mitigating tissue inflammation and restoring redox homeostasis through the NF-κB-NLRP3 signaling pathway. Hence, the application of FA has been found to be efficacious for improving respiratory inhibition and mitigating gill tissue inflammation and oxidative stress resulting from DFZ pollution in aquatic habitats.

The influence of simulated weightlessness on the composition and function of gut microbiota and bile acid metabolism products.

The aim of this study was to investigate the effects of simulated weightlessness on gut microbiota, bile acid metabolism, and inflammatory cytokines compared to the control group. The study compared the changes in gut microbiota at the phylum and genus levels in the feces of control and weightlessness rats after 1 and 8 weeks using fecal 16S rRNA sequencing. In the weightlessness group, there was an increase in the proportion of anaerobic bacteria and biofilm-forming bacteria, and a decrease in the proportion of aerobic and Gram-negative bacteria. Further investigations explored the impact of weightlessness on bile acid metabolism products. The levels of glycine ursodeoxycholic acid, glycine chenodeoxycholic acid, glycine deoxycholic acid and glycine cholic acid levels were lower in rats undergoing weightlessness for 1 week compared to the control group.Moreover, the study examined the relationship between gut microbiota and bile acid metabolism products.It was observed that, unlike the control group, there were significant positive correlations between Planctomycetes, Proteobacteria, Synergistetes, and GUDCA levels in rats after 1 week of weightlessness. Finally, ELISA results indicated significant differences in the levels of MDA, GSH, NLRP3, and SIgA inflammatory cytokines between rats undergoing weightlessness for 1 week and the control group rats. Our research confirmed that the simulated weightlessness environment significantly affects the gut microbiota and bile acid metabolism in rats, potentially leading to changes in inflammatory cytokines and causing intestinal tissue inflammation. Further exploring the relationship between gut microbiota and bile acid metabolism under weightless conditions will be crucial for understanding the functional changes in the intestines caused by weightlessness.

Toxicological responses of A549 and HCE-T cells exposed to fine particulate matter at the air-liquid interface.

Fine particulate matter (PM2.5) can enter the human body in various ways and have adverse effects on human health. Human lungs and eyes are exposed to the air for a long time and are the first to be exposed to PM2.5. The "liquid immersion exposure method" has some limitations that prevent it from fully reflecting the toxic effects of particulate matter on the human body. In this study, the collected PM2.5 samples were chemically analyzed. An air-liquid interface (ALI) model with a high correlation to the in vivo environment was established based on human lung epithelial cells (A549) and immortalized human corneal epithelial cells (HCE-T). The VITROCELL Cloud 12 system was used to distribute PM2.5 on the cells evenly. After exposure for 6 h and 24 h, cell viability, apoptosis rate, reactive oxygen species (ROS) level, expression of inflammatory factors, and deoxyribonucleic acid (DNA) damage were measured. The results demonstrated significant dose- and time-dependent effects of PM2.5 on cell viability, cell apoptosis, ROS generation, and DNA damage at the ALI, while the inflammatory factors showed dose-dependent effects only. It should be noted that even short exposure to low doses of PM2.5 can cause cell DNA double-strand breaks and increased expression of γ-H2AX, indicating significant genotoxicity of PM2.5. Increased abundance of ROS in cells plays a crucial role in the cytotoxicity induced by PM2.5 exposure These findings emphasize the significant cellular damage and genotoxicity that may result from short-term exposure to low levels of PM2.5.

Correlational analysis of PLIN1 with inflammation in diabetic foot ulcer wounds.

BACKGROUND: The persistent presence of inflammation is a recognized pathogenic mechanisms of diabetic foot ulcers (DFUs). We aimed to investigate the expression of PLIN1 in tissues from DFU patients and assess its potential association with inflammation-induced damage. METHODS: We performed transcriptome sequencing and correlation analysis of the foot skin from patients with or without DFUs. Additionally, we examined the correlation between PLIN1 and related inflammatory indicators by analyzing PLIN1 expression in tissue and serum samples and through high-glucose stimulation of keratinocytes (HaCaT cells). RESULTS: PLIN1 is upregulated in the tissue and serum from DFU patients. Additionally, PLIN1 shows a positive correlation with leukocytes, neutrophils, monocytes, C-reactive protein, and procalcitonin in the serum, as well as IL-1ß and TNF-α in the tissues. Experiments with Cells demonstrated that reduced expression of PLIN1 leads to significantly decreased expression of iNOS, IL-1ß, IL-6, IL-18, and TNF-α. PLIN1 may mediate wound inflammatory damage through the NF-κB signaling pathway. CONCLUSION: Our findings suggest that PLIN1 mediates the inflammatory damage in DFU, offering new prospects for the treatment of DFU.

Manganese dioxide nanoparticles provoke inflammatory damage in BV2 microglial cells via increasing reactive oxygen species to activate the p38 MAPK pathway.

With the widespread use of manganese dioxide nanoparticles (nano MnO2), health hazards have also emerged. The inflammatory damage of brain tissues could result from nano MnO2, in which the underlying mechanism is still unclear. During this study, we aimed to investigate the role of ROS-mediated p38 MAPK pathway in nano MnO2-induced inflammatory response in BV2 microglial cells. The inflammatory injury model was established by treating BV2 cells with 2.5, 5.0, and 10.0 µg/mL nano MnO2 suspensions for 12 h. Then, the reactive oxygen species (ROS) scavenger (20 nM N-acetylcysteine, NAC) and the p38 MAPK pathway inhibitor (10 µM SB203580) were used to clarify the role of ROS and the p38 MAPK pathway in nano MnO2-induced inflammatory lesions in BV2 cells. The results indicated that nano MnO2 enhanced the expression of pro-inflammatory cytokines IL-1ß and TNF-α, elevated intracellular ROS levels and activated the p38 MAPK pathway in BV2 cells. Controlling intracellular ROS levels with NAC inhibited p38 MAPK pathway activation and attenuated the inflammatory response induced by nano MnO2. Furthermore, inhibition of the p38 MAPK pathway with SB203580 led to a decrease in the production of inflammatory factors (IL-1ß and TNF-α) in BV2 cells. In summary, nano MnO2 can induce inflammatory damage by increasing intracellular ROS levels and further activating the p38 MAPK pathway in BV2 microglial cells.

The activation of SIRT1 ameliorates BPDE-induced inflammatory damage in BEAS-2B cells via HMGB1/TLR4/NF-κB pathway.

Benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE), the metabolite of environmental pollutant benzo(a)pyrene (B(a)P) could induce pulmonary toxicity and inflammation. SIRT1, an NAD+ -dependent histone deacetylase, is known to regulate inflammation in the occurrence and development of various diseases, but its effects on BPDE-induced acute lung injury are still unknown. The present study aimed to explore the role of SIRT1 in BPDE-induced acute lung injury. Here, human bronchial epithelial (HBE) cells (BEAS-2B) cells were stimulated with BPDE at different concentrations (0.50, 0.75, and 1.00 µmol/L) for 24 h, we found that the levels of cytokines in the supernatant were increased and the expression of SIRT1 in cells was down-regulated, at the same time, BPDE stimulation up-regulated the protein expression of HMGB1, TLR4, and p-NF-κBp65 in BEAS-2B cells. Then the activator and inhibitor of SIRT1 were used before BPDE exposure, it was shown that the activation of SIRT1 significantly attenuated the levels of inflammatory cytokines and HMGB1, and reduced the expression of HMGB1, AC-HMGB1, TLR4, and p-NF-κBp65 protein; while these results were reversed by the inhibition of SIRT1. This study revealed that the SIRT1 activation may protect against BPDE-induced inflammatory damage in BEAS-2B cells by regulating the HMGB1/TLR4/NF-κB pathway.

Human TFF2-Fc fusion protein alleviates DSS-induced ulcerative colitis in C57BL/6 mice by promoting intestinal epithelial cells repair and inhibiting macrophage inflammation.

The clinical drugs for ulcerative colitis mainly affect the inflammatory symposiums with limited outcomes and various side effects. Repairing the damaged intestinal mucosa is a promising and alternative strategy to treat ulcerative colitis. Trefoil factor family 2 (TFF2) could repair the intestinal mucosa, however, it has a short half-life in vivo. To improve the stability of TFF2, we have prepared a new fusion protein TFF2-Fc with much stability, investigated the therapeutic effect of TFF2-Fc on ulcerative colitis, and further illustrated the related mechanisms. We found that intrarectally administered TFF2-Fc alleviated the weight loss, the colon shortening, the disease activity index, the intestinal tissue injury, and the lymphocyte infiltration in dextran sulfate sodium (DSS)-induced colitis mice. In vitro, TFF2-Fc inhibited Caco2 cells injury and apoptosis, promoted cellular migration, and increased the expression of Occludin and ZO-1 by activating P-ERK in the presence of H2O2 or inflammatory conditioned medium (LPS-RAW264.7/CM). Moreover, TFF2-Fc could reduce lipopolysaccharide (LPS)-induced production of inflammation cytokines and reactive oxygen species in RAW264.7 cells, and also inhibits the polarization of RAW264.7 cells to M1 phenotype by reducing glucose consumption and lactate production. Taken together, in this work, we have prepared a novel fusion protein TFF2-Fc, which could alleviate ulcerative colitis in vivo via promoting intestinal epithelial cells repair and inhibiting macrophage inflammation, and TFF2-Fc might serve as a promising ulcerative colitis therapeutic agent.

Diosgenin alleviates the inflammatory damage and insulin resistance in high glucose­induced podocyte cells via the AMPK/SIRT1/NF­κB signaling pathway.

Diabetic nephropathy (DN) is the predominant cause of end-stage renal disease globally. Diosgenin (DSG) has been reported to play a protective role in podocyte injury in DN. The present study aimed to explore the role of DSG in DN, as well as its mechanism of action in a high glucose (HG)-induced in vitro model of DN in podocytes. Cell viability, apoptosis, inflammatory response and insulin-stimulated glucose uptake were evaluated using Cell Counting Kit-8, TUNEL, ELISA and 2-deoxy-D-glucose assay, respectively. In addition, the expression of AMP-activated protein kinase (AMPK)/sirtuin 1 (SIRT1)/NF-κB signaling-related proteins in podocyte cells was measured using western blotting. The results indicated that DSG enhanced the viability of podocytes after HG exposure, but inhibited inflammatory damage and attenuated insulin resistance. Moreover, DSG induced the activation of the AMPK/SIRT1/NF-κB signaling pathway. Furthermore, treatment with compound C, an inhibitor of AMPK, counteracted the protective effects of DSG on HG-induced podocyte cells. Therefore, DSG may be a potential therapeutic compound for the treatment of diabetic nephropathy.

Bowel inflammatory presentations on computed tomography in adult patients with severe aplastic anemia during flared inflammatory episodes.

BACKGROUND: Patients with severe aplastic anemia (SAA) frequently present with inflammatory episodes, and during flared inflammatory episodes, hematopoietic function is further exacerbated. The gastrointestinal tract is the most common site for infectious and inflammatory diseases, and its structural and functional features confer on it the most potent capacity to affect hematopoietic and immune functions. Computed tomography (CT) is a readily accessible approach to provide highly useful information in detecting morphological changes and guiding further work-ups. AIM: To explore CT imaging presentations of gut inflammatory damage in adult SAA patients during inflammatory episodes. METHODS: We retrospectively evaluated the abdominal CT imaging presentations of 17 hospitalized adult patients with SAA in search of the inflammatory niche when they presented with systemic inflammatory stress and exacerbated hematopoietic function. In this descriptive manuscript, the characteristic images that suggested the presence of gastrointestinal inflammatory damage and related imaging presentations of individual patients were enumerated, analyzed and described. RESULTS: All eligible patients with SAA had CT imaging abnormalities that suggested the presence of an impaired intestinal barrier and increased epithelial permeability. The inflammatory damages were concurrently present in the small intestine, the ileocecal region and the large intestines. Some readily identified imaging signs, such as bowel wall thickening with mural stratification ("water holo sign", "fat holo sign", intramural gas and subserosal pneumatosis) and mesenteric fat proliferation (fat stranding and "creeping fat sign"), fibrotic bowel wall thickening, "balloon sign", rugged colonic configuration, heterogeneity in the bowel wall texture, and adhered and clustered small bowel loop (including various patterns of "abdominal cocoon"), occurred at a high incidence, which suggested that the damaged gastrointestinal tract is a common inflammatory niche responsible for the systemic inflammatory stresses and the exacerbated hematopoietic failure in patients with SAA. Particularly, the "fat holo sign" was present in 7 patients, a rugged colonic configuration was present in 10 patients, the adhesive bowel loop was present in 15 patients, and extraintestinal manifestations suggestive of tuberculosis infections were present in 5 patients. According to the imaging features, a suggestive diagnosis of Crohn's disease was made in 5 patients, ulcerative colitis in 1 patient, chronic periappendiceal abscess in 1 patient, and tuberculosis infection in 5 patients. Other patients were diagnosed with chronic enteroclolitis with acutely aggravated inflammatory damage. CONCLUSION: Patients with SAA had CT imaging patterns that suggested the presence of active chronic inflammatory conditions and aggravated inflammatory damage during flared inflammatory episodes.

Loss of RPA1 Impairs Peripheral T Cell Homeostasis and Exacerbates Inflammatory Damage through Triggering T Cell Necroptosis.

The peripheral T cell pool is maintained at dynamic homeostasis through fine-tuning of thymic output and self-renewal of naïve T cells. Lymphopenia or reduced lymphocyte number is implicated in autoimmune diseases, yet little is known about the homeostatic mechanisms. Here, it is reported that the replication protein A1 (RPA1) plays a critical role in T cell homeostasis. Utilizing T cell-specific Rpa1-deficient (Rpa1fl/fl Cd4-cre) mice, loss of Rpa1 results in lymphopenia through restraining peripheral T cell population and limiting TCR repertoire diversity. Moreover, Rpa1fl/fl Cd4-cre mice exhibit increased susceptibility to inflammatory diseases, including colitis and hepatitis. Clinical analysis reveals that the expression of RPA1 is reduced in patients with ulcerative colitis or other autoinflammatory diseases. Mechanistically, depletion of RPA1 activates ZBP1-RIPK3 signaling through triggering the genomic DNA leakage into cytosol, consequently resulting in T cell necroptosis. This necroptotic T cell death induced by RPA1 deficiency allows the release of damage-associated molecular patterns (DAMPs), which in turn recruits leukocytes and exacerbates inflammatory response. Reciprocally, chemical or genetic inhibition of necroptosis signaling can ameliorate the Rpa1 deficiency-induced inflammatory damage. The studies thus uncover the importance of RPA1-ZBP1-RIPK3 axis in T cell homeostasis and provide a promising strategy for autoinflammatory disease treatment.

Sodium Butyrate Attenuates AGEs-Induced Oxidative Stress and Inflammation by Inhibiting Autophagy and Affecting Cellular Metabolism in THP-1 Cells.

In recent years, sodium butyrate has gained increased attention for its numerous beneficial properties. However, whether sodium butyrate could alleviate inflammatory damage by macrophage activation and its underlying mechanism remains unclear. The present study used an advanced glycosylation products- (AGEs-) induced inflammatory damage model to study whether sodium butyrate could alleviate oxidative stress, inflammation, and metabolic dysfunction of human monocyte-macrophage originated THP-1 cells in a PI3K-dependent autophagy pathway. The results indicated that sodium butyrate alleviated the AGEs-induced oxidative stress, decreased the level of reactive oxygen species (ROS), increased malondialdehyde (MDA) and mRNA expression of pro-inflammatory cytokines of interleukin (IL)-1ß and tumor necrosis factor (TNF)-α, and increased the content of superoxide dismutase (SOD). Sodium butyrate reduced the protein expression of the NLR family, pyrin domain-containing protein 3 (NLRP3) and Caspase-1, and decreased the nucleus expression of nuclear factor-kappaB (NF-κB). Sodium butyrate decreased the expression of light-chain-associated protein B (LC3B) and Beclin-1, and inhibited autophagy. Moreover, sodium butyrate inhibited the activation of the PI3K/Akt pathway in AGEs-induced THP-1 cells. In addition, the metabolomics analysis showed that sodium butyrate could affect the production of phosphatidylcholine, L-glutamic acid, UDP-N-acetylmuraminate, biotinyl-5'-AMP, and other metabolites. In summary, these results revealed that sodium butyrate inhibited autophagy and NLRP3 inflammasome activation by blocking the PI3K/Akt/NF-κB pathway, thereby alleviating oxidative stress, inflammation, and metabolic disorder induced by AGEs.

Diosgenin protects retinal pigment epithelial cells from inflammatory damage and oxidative stress induced by high glucose by activating AMPK/Nrf2/HO-1 pathway.

INTRODUCTION: Diosgenin is a natural steroidal compound with reported antidiabetic and many other protective properties. This study aimed to explore the protective effect of diosgenin on high-glucose (HG)-induced retinal pigment epithelial cells. METHODS: HG-induced ARPE-19 cells were considered as a cell model of diabetic retinopathy (DR). The viability and apoptosis of ARPE-19 cells induced by HG treated with either diosgenin or Compound C (CC; dorsomorphin) were detected by Cell Counting Kit-8 assay and flow cytometric analysis. The expression of apoptosis-related proteins, inflammation-related proteins, and AMPK/Nrf2/HO-1 pathway-related proteins was detected by western blotting. The levels of inflammatory cytokines and detection of oxidative stress indexes were performed using the appropriate assay kits. The messenger RNA expression of inflammatory cytokines was detected by real-time quantitative polymerase chain reaction. RESULTS: There was no obvious effect of diosgenin on the viability of ARPE-19 cells and the viability of ARPE-19 cells was significantly reduced after HG induction. However, diosgenin increased the viability, inhibited the apoptosis, and reduced the inflammatory response and oxidative stress of ARPE-19 cells induced by HG. In addition, diosgenin could activate the AMPK/Nrf2/HO-1 pathway. CC, an AMPK inhibitor, could reverse the above changes caused by diosgenin treatment in ARPE-19 cells induced by HG. CONCLUSIONS: Diosgenin could protect ARPE-19 cells from inflammatory damage and oxidative stress induced by HG, by activating the AMPK/Nrf2/HO-1 pathway.

Modulation of Alveolar Macrophages by Postimmunobiotics: Impact on TLR3-Mediated Antiviral Respiratory Immunity.

Beneficial microbes with immunomodulatory capacities (immunobiotics) and their non-viable forms (postimmunobiotics) could be effectively utilized in formulations towards the prevention of respiratory viral infections. In this study, novel immunobiotic strains with the ability to increase antiviral immunity in porcine alveolar macrophages were selected from a library of Lactobacillus gasseri. Postimmunobiotics derived from the most remarkable strains were also evaluated in their capacity to modulate the immune response triggered by Toll-like receptor 3 (TLR3) in alveolar macrophages and to differentially regulate TLR3-mediated antiviral respiratory immunity in infant mice. We provide evidence that porcine alveolar macrophages (3D4/31 cells) are a useful in vitro tool for the screening of new antiviral immunobiotics and postimmunobiotics by assessing their ability to modulate the expression IFN-ß, IFN-λ1, RNAseL, Mx2, and IL-6, which can be used as prospective biomarkers. We also demonstrate that the postimmunobiotics derived from the Lactobacillus gasseri TMT36, TMT39 and TMT40 (HK36, HK39 or HK40) strains modulate the innate antiviral immune response of alveolar macrophages and reduce lung inflammatory damage triggered by TLR3 activation in vivo. Although our findings should be deepened and expanded, the results of the present work provide a scientific rationale for the use of nasally administered HK36, HK39 or HK40 to beneficially modulate TLR3-triggerd respiratory innate immune response.

Complanatuside alleviates inflammatory cell damage induced by pro-inflammatory cytokines in skin keratinocytes.

Cytokine-mediated inflammatory response is considered a cause of skin lesion in COVID-19 patients. Complanatuside is a flavonol glycoside isolated from Astragalus complanatus. Flavonoids from Astragalus complanatus were reported to have anti-inflammatory and anticancer activities but the potential protective effect of complanatuside on cytokine-induced inflammatory damage in skin keratinocytes is not known. The aim of this study is to explore the inhibitory effect of complanatuside on inflammation and its underlying mechanisms in skin epithelial HaCaT cells treated with inflammatory cytokines. The combination of IFN-γ, TNF-α, and IL-6 decreased cell viability, increased cell death, and pyroptosis in HaCaT cells. Treatment with complanatuside alleviated the effects of the cytokine combination on HaCaT cells. Complanatuside down-regulated pyroptosis related to NLRP3, GSDMD, and ASC. The effects of complanatuside were related to vast reductions in the levels of iNOS, COX-2, and ROS. Results of the present study indicate that complanatuside inhibited inflammation and protected the cells from inflammatory cell damage in HaCaT cells treated with the combination of IFN-γ, TNF-α, and IL-6. Complanatuside may be a promising candidate for inhibiting COVID-19 related skin inflammatory damage.

Exposure to particulate matter 2.5 leading to lung microbiome disorder and the alleviation effect of Auricularia auricular-judae polysaccharide.

OBJECTIVES: The aim of the paper is to explore the role of lung microbiome disorder in lung tissue injury induced by exposure to particulate matter with a maximum diameter of 2.5 µm (PM2.5) and the alleviation effect of Auricularia auricular-judae polysaccharide (AAP). MATERIAL AND METHODS: Sprague Dawley rats were given PM2.5 suspension at a dose of 20 mg/l twice a week for 8 weeks. Then, 100 mg/kg or 200 mg/kg of AAP was administered to the rats after PM2.5 exposure. The bronchoalveolar lavage fluid (BALF) and lung tissue samples were collected at the end of the experiment. The BALF was meant to detect changes in lung microbiome by 16S sequences and cluster analysis, with the application of the principal component analysis and the partial least squares discriminant analysis. The levels of interferon-γ (IFN-γ), and interleukin (IL)-4, IL-8, and IL-10 in lung tissue were detected by the enzyme-linked immunosorbent assay method. The pathological changes in lung tissue were observed by hematoxylin and eosin staining. RESULTS: After PM2.5 exposure, the alveolar septum was widened, and the structures of alveolar walls were destroyed. There was inflammatory cells infiltration in the alveolar space and the interstitial space. Alpha diversity in BALF showed that the Chao1, ACE, Simpson, and Shannon values were increased, and the lung microbiome analysis revealed that the relative abundance of Firmicutes and Clostridium increased, while the relative abundance of Bacteroidetes and Akkermansia decreased. The contents of IFN-γ and IL-8 in lung tissue increased while the content of IL-10 decreased. After the administration of AAP, the alveolar structure damage was alleviated, and the interstitial hemorrhage, edema, and inflammatory cells infiltration were reduced. The Chao1 and ACE values decreased, and the taxonomic abundance values of Akkermansia were much higher. Simultaneously, the contents of IFN-γ, IL-4, and IL-8 decreased, and the content of IL-10 increased. CONCLUSIONS: It was found that PM2.5 resulted in lung microbiome disorder, which might lead to the inflammation of lung tissue. It was also revealed that AAP could alleviate the inflammatory damage of lung tissue induced by PM2.5. Int J Occup Med Environ Health. 2022;35(6):651-64.

Bone Marrow-Derived Mesenchymal Stem Cell-Derived Exosomes Containing Gli1 Alleviate Microglial Activation and Neuronal Apoptosis In Vitro and in a Mouse Parkinson Disease Model by Direct Inhibition of Sp1 Signaling.

This study investigated possible therapeutic effect mechanisms of exosomes from bone marrow-derived mesenchymal stem cells (BMSC) in neuronal and microglial cells and in a Parkinson disease (PD) model. Neuronal SH-SY5Y cells and microglial HMC3 cells were subjected to 1-methyl-4-phenylpyridinium (MPP+) or LPS, respectively. The mRNA and protein expression was assessed using qRT-PCR, Western blotting, and enzyme-linked immunosorbent assay. Cell viability and apoptosis of SH-SY5Y cells were examined using the MTT assay and flow cytometry. Chromatin immunoprecipitation assays were performed to assess the binding relationship between glioma-associated oncogene homolog 1 (Gli1) and the Sp1 transcription factor promoter. BMSC-derived exosomes promoted cell proliferation and inhibited apoptosis in MPP+-treated SH-SY5Y cells and suppressed inflammatory markers in LPS-treated HMC3 cells. Sp1 knockdown decreased SH-SY5Y cell damage and HMC3 immune activation. Gli1 carried by BMSC exosomes directly bound with Sp1 to inhibit Sp1-mediated LRRK2 activation whereas exosomes secreted by Gli1-knockdown in BMSC did not. In a PD mouse model induced with MPTP, BMSC exosomes decreased neuron loss injury and the inflammatory response by inhibiting Sp1 signaling. Thus, BMSC-derived exosomal Gli1 alleviates inflammatory damage and neuronal apoptosis by inhibiting Sp1 in vitro and in vivo. These findings provide the basis for the potential clinical use of BMSC-derived exosomes in PD.

Bovine Lactoferrin Alleviates Pulmonary Lipid Peroxidation and Inflammatory Damage in Heat Stroke Rats.

Lung injury occurring in the early stage of heat stroke (HS) leads to hypoxia and further aggravation of other organic damage. Lactoferrin (LF) is an iron binding protein with anti-inflammatory and antioxidant effects. This study focuses on the protection of preadministration of bovine lactoferrin (BLF) against lung injury in rats with HS. Sixty-four Sprague-Dawley male rats were divided into four groups randomly: control (CON)+phosphate-buffered saline (PBS) (n = 16), HS+PBS (n = 16), HS+low-dose BLF (LBLF) (n = 16), and HS+high-dose BLF (HBLF) (n = 16). CON+PBS and HS+PBS were preadministered 10 mL/kg PBS for 1 week. HS+LBLF and HS+HBLF were preadministered 100 and 200 mg/kg BLF for 1 week, respectively. The HS onset time and the survival rate were recorded, and bronchoalveolar lavage fluid was obtained to measure protein concentration. Lung was obtained for pathological analysis and wet/dry weight ratio measurement; later, the content of malondialdehyde (MDA), activity of myeloperoxidase (MPO), and superoxide dismutase (SOD) were measured in lung tissue homogenate. The results indicated that BLF preadministration could delay the HS onset time, enhance the survival rate, the levels of serum inflammatory cytokine and MDA content in HS+LBLF and HS+HBLF showed significant reduction compared with HS+PBS, while a significant elevation of SOD activity and reduction of MPO activity in HS+HBLF. Our results demonstrate that BLF preadministration could relieve lung injury in HS rats by enhancing thermal endurance, and alleviating serum inflammatory response and pulmonary oxidative stress damage.