Astilbin protects against cerebral ischaemia/reperfusion injury by inhibiting cellular apoptosis and ROS-NLRP3 inflammasome axis activation

BackgroundIschaemic stroke is a lethal cerebrovascular disease that occurs worldwide. Astilbin is a natural flavonoid compound with various physiological activities. The purpose of this study was to investigate the neuroprotective effects of Astilbin after cerebral ischaemia reperfusion (I/R) injury.MethodsThe oxygen and glucose deprivation (OGD) model was used to simulate cerebral I/R injury in vitro. Cell viability was measured via CCK-8 and LDH release assays. Cell apoptosis was measured via Hoechst 33258 staining and flow cytometry assays. ROS was detected via flow cytometry assay. The protein expression levels were determined by western blotting. The middle cerebral artery occlusion (MCAO) model was used to simulate cerebral I/R injury in vivo. Cerebral ischaemic volume was measured by TTC staining. The Zea-Longa score, rota-rod test, and foot-fault test were used to evaluate behavioural changes and neurological deficits in rats.ResultsAstilbin significantly enhanced cell viability and decreased LDH release after OGD treatment in vitro. Astilbin effectively curbed cell apoptosis induced by OGD via inhibiting the activation of caspase-3, decreasing the ratio of Bax/Bcl-2 and decreasing FADD. Astilbin also inhibited OGD-induced inflammation by suppressing ROS-NLRP3 inflammasome axis activation. Further results revealed that Astilbin could suppress the MAPK pathway and activate the PI3K/AKT pathway. Finally, Astilbin significantly reduced the cerebral infarction volume and relieved neurological deficits in rats in vivo.ConclusionAstilbin could defend against cerebral I/R injury by inhibiting apoptosis and inflammation via suppressing the MAPK pathway and activating the AKT pathway.     

Chrysophanol protects against doxorubicin-induced cardiotoxicity by suppressing cellular PARylation

The clinical application of doxorubicin (DOX) in cancer chemotherapy is limited by its life-threatening cardiotoxic effects. Chrysophanol (CHR), an anthraquinone compound isolated from the rhizome of Rheum palmatum L., is considered to play a broad role in a variety of biological processes. However, the effects of CHR׳s cardioprotection in DOX-induced cardiomyopathy is poorly understood. In this study, we found that the cardiac apoptosis, mitochondrial injury and cellular PARylation levels were significantly increased in H9C2 cells treated by Dox, while these effects were suppressed by CHR. Similar results were observed when PARP1 activity was suppressed by its inhibitors 3-aminobenzamide (3AB) and ABT888. Ectopic expression of PARP1 effectively blocked this CHR׳s cardioprotection against DOX-induced cardiomyocyte injury in H9C2 cells. Furthermore, pre-administration with both CHR and 3AB relieved DOX-induced cardiac apoptosis, mitochondrial impairment and heart dysfunction in Sprague–Dawley rat model. These results revealed that CHR protects against DOX-induced cardiotoxicity by suppressing cellular PARylation and provided critical evidence that PARylation may be a novel target for DOX-induced cardiomyopathy.     

Gambogic acid alleviates inflammation and apoptosis and protects the blood-milk barrier in mastitis induced by LPS

Mastitis is one of the most common diseases among dairy cows. There is still much debate worldwide as to whether antibiotic therapy should be given to dairy cows, or if natural products should be taken as a substitute for antibacterial therapy. As the antibiotic treatment leads to the bacterial resistance and drug residue in milk, introducing natural products for mastitis is becoming a trend. This study investigates the mechanisms of the protective effects of the natural product gambogic acid (GA) in lipopolysaccharide (LPS)-induced mastitis. For in vitro treatments, it was found that GA reduced IL-6, TNF-α, and IL-1β levels by inhibiting the phosphorylation of proteins in the nuclear factor κB (NF-κB) and the mitogen-activated protein kinase (MAPK) pathway. GA also maintained a stable membrane mitochondrial potential and inhibited the overproduction of reactive oxygen species, which protected the cells from apoptosis. On the other hand, in vivo treatments with GA were found to reduce pathological symptoms markedly, and protected the blood-milk barrier from damage induced by LPS. The results demonstrate that GA plays a vital role in suppressing inflammation, alleviating the apoptosis effect, and protecting the blood-milk barrier in mastitis induced by LPS. Thus, these results suggest that the natural product GA plays a potential role in mastitis treatment.     

Phillyrin protects mice from traumatic brain injury by inhibiting the inflammation of microglia via PPARγ signaling pathway

The neuroinflammatory response induced by microglia plays a vital role in causing secondary brain damage after traumatic brain injury (TBI). Previous studies have found that the improved regulation of activated microglia could reduce neurological damage post-TBI. Phillyrin (Phi) is one of the main active ingredients extracted from the fruits of the medicinal plant Forsythia suspensa (Thunb.) with anti-inflammatory effects. Our study attempted to investigate the effects of phillyrin on microglial activation and neuron damage after TBI. The TBI model was applied to induce brain injury in mice, and neurological scores, brain water content, hematoxylin and eosin staining and Nissl staining were employed to determine the neuroprotective effects of phillyrin. Immunofluorescent staining and western blot analysis were used to detect nuclear factor-kappa B (NF-κB) and peroxisome proliferator–activated receptor gamma (PPARγ) expression and nuclear translocation, and the inflammation-related proteins and mRNAs were assessed by western blot analysis and quantitative real-time PCR. The results revealed that phillyrin not only inhibited the proinflammatory response induced by activated microglia but also attenuated neurological impairment and brain edema in vivo in a mouse TBI model. Additionally, phillyrin suppressed the phosphorylation of NF-κB in microglia after TBI insult. These effects of phillyrin were mostly abolished by the antagonist of PPARγ. Our results reveal that phillyrin could prominently inhibit the inflammation of microglia via the PPARγ signaling pathway, thus leading to potential neuroprotective treatment after traumatic brain injury.     

Therapeutic effects of AdipoRon on liver inflammation and fibrosis induced by CCl4 in mice

ObjectiveThe present work aimed to investigate the effects of AdipoRon against acute hepatitis and liver fibrosis induced by carbon tetrachloride (CCl₄) in mice.MethodsC57BL/6 mice were randomly divided into five groups: control, model, AdipoRon groups (three different dosages), CCl₄ was administered to induce acute hepatitis or liver fibrosis except for control group. The liver function, inflammatory and fibrotic profiles were evaluated by histology, immunohistochemistry and expression analysis, respectively.ResultsAdipoRon pretreatment effectively attenuated oxidative stress and hepatocellular damage in acute CCl₄ intoxication, demonstrated by marked reduction in peroxidation indexes [hepatic malonaldehyde (MDA), total nitric oxide synthase (tNOS), inducible nitric oxide synthase (iNOS)] and serum transaminases [alanine aminotransferase (ALT), aspartate transaminase (AST)]. Moreover, AdipoRon attenuated the severity of fibrosis induced by sustaining CCl₄ challenge, with the alleviation of fibrous deposit and architecture distortion. The levels of canonical fibrosis markers (aminotransferases, hydroxyproline, hyaluronic acid, laminin) were also dose-dependently modulated by AdipoRon. Immunochemistry and expression analysis showed AdipoRon restrained the proinflammatory and profibrotic cytokines (TNF-α, TGF-β1, α-SMA, COL1A1), which somehow, ascribed the anti-fibrotic action to inhibiting hepatic stellate cells (HSCs) activation and quenching specific inflammation-fibrogenesis pathways.ConclusionsAdipoRon demonstrates a remedial capacity against hepatitis and fibrosis induced by CCl₄, potentially by inflammation restraint and HSC deactivation, which might pave the way for its therapeutical application in hepatic fibrosis.     

Calcitriol inhibits lipopolysaccharide-induced proliferation,migration and invasion of prostate cancer cells through suppressing STAT3 signal activation

Increasing evidence suggests that infection promotes the initiation and progression of prostate cancer. This study investigated the effects of lipopolysaccharide (LPS), a major component of Gram-negative bacilli, on proliferation, migration and invasion of prostate cancer cells and the protective effects of 1α,25(OH)₂D₃ (calcitriol). PC-3 and DU145 cells were stimulated with LPS (2.0 μg/mL) in the presence or absence of 1α,25(OH)₂D₃ (100 nM). Our results shown that 1α,25(OH)₂D₃ reduced the proportion of S phase cells in LPS-stimulated PC-3 and DU145 cells, and down-regulated the nuclear protein levels of Cyclin D1 and PCNA in LPS-stimulated PC-3 cells. In addition, 1α,25(OH)₂D₃ inhibited migration and invasion, as determined by wound healing and transwell assay, in LPS-stimulated PC-3 and DU145 cells. Of interest, we observed that 1α,25(OH)₂D₃ inhibits NF-κB activation and subsequent synthesis and secretion of IL-6 and IL-8 by promoting VDR and NF-κB p65 interaction. Surprisingly, 1α,25(OH)₂D₃ blocks nuclear translocation of pSTAT3 by promoting physical interaction between VDR and pSTAT3 (Tyr705) in LPS-stimulated PC-3 and DU145 cells. These results suggest that 1α,25(OH)₂D₃ inhibits LPS-induced proliferation, migration and invasion in prostate cancer cells by directly and indirectly blocking STAT3 signal transduction.     

MiR-215-5p inhibits the inflammation injury in septic H9c2 by regulating ILF3 and LRRFIP1

MicroRNAs (miRNAs) are small non-coding RNAs (ncRNAs) playing crucial roles in sepsis-induced diseases, including myocardial inflammation. Nevertheless, the expression pattern and role of miR-215-5p in myocardial inflammation are still un-investigated up to now. The purpose of our study is to further inquire the effect of miR-215-5p on lipopolysaccharide (LPS)-activated inflammation injury in H9c2 cells and the possibly associated mechanisms. First of all, LPS-induced H9c2 cells models were constructed and affirmed via detection of pro-inflammatory factors, the viability and apoptosis. MiR-215-5p was overtly down-regulated in LPS-treated H9c2 cells and miR-215-5p overexpression could suppress the inflammation injury. LRRFIP1 was proved to be the target gene of miR-215-5p and meanwhile, miR-215-5p also targeted ILF3 that experimented to bind to and stabilize LRRFIP1. Final rescue assays confirmed that the overexpression of LRRFIP1 or ILF3 rescued the repressive effect of miR-215-5p up-regulation on the inflammation injury in septic H9c2. Totally, miR-215-5p exerted protective function in the inflammation injury in septic H9c2 via targeting ILF3 and LRRFIP1, suggesting an additional treatment method for sepsis-activated myocardial inflammation.     

MiR-92b-3p ameliorates inflammation and autophagy by targeting TRAF3 and suppressing MKK3-p38 pathway in caerulein-induced AR42J cells

Acute pancreatitis (AP) is an inflammatory disease with high morbidity and mortality. Dysregulation of microRNAs (miRNAs) was involved in human diseases, including AP. However, the effects of miR-92b-3p on AP process and its mechanism remain not been fully clarified. The expression levels of miR-92b-3p and tumor necrosis factor receptor-associated factor-3 (TRAF3) were measured by quantitative real-time polymerase chain reaction (qRT-PCR). The protein levels of TRAF3, tumor necrosis factor α (TNF-α) TNF-α, interleukin-6 (IL-6), phosphorylated mitogen-activated protein kinase kinase 3 (p-MKK3), MKK3, p38 and phosphorylated p38 (p-p38) were detected by western blot. The concentration of TNF-α and IL-6 in the medium was measured using ELISA kits. The possible binding sites of miR-92b-3p and TRAF3 were predicted by TargetScan and verified by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. The expression level of miR-92b-3p was decreased and TRAF3 expression was increased in AR42J cells stimulated with caerulein. Moreover, the protein levels of pro-inflammatory cytokines (TNF-α and IL-6) were markedly elevated, and the expression levels of autophagy-related markers Beclin1 as well as the ratio of LC3-II/I were obviously increased in AR42J cells treated with caerulein. In addition, overexpression of miR-92b-3p or knockdown of TRAF3 significantly suppressed the release of pro-inflammatory cytokines and autophagy in caerulein-induced AR42J cells. Furthermore, TRAF3 was a direct target of miR-92b-3p and its upregulation reversed the effects of miR-92b-3p overexpression on inflammatory response and autophagy. Besides, overexpression of miR-92b-3p inhibited the activation of the MKK3-p38 pathway by affecting TRAF3 expression. In conclusion, miR-92b-3p attenuated inflammatory response and autophagy by downregulating TRAF3 and suppressing MKK3-p38 pathway in caerulein-induced AR42J cells, providing a novel avenue for treatment of AP.     

Knockdown of PVT1 inhibits IL-1β-induced injury in chondrocytes by regulating miR-27b-3p/TRAF3 axis

Long noncoding RNA plasmacytoma variant translocation 1 (PVT1) has been identified to implicate in the progression of osteoarthritis (OA). However, the mechanism underlying PVT1 in OA development remains largely unknown. This study aimed to investigate the effect of PVT1 on interleukin-1 beta (IL-1β)-induced injury in chondrocytes and explore potential mechanism. The cartilage tissues from 25 OA patients and normal controls were collected. Human transformed chondrocytes C28/I2 were stimulated by IL-1β. The levels of PVT1, microRNA (miR)-27b-3p, and tumor necrosis factor receptor-associated factor 3 (TRAF3) were detected by quantitative real-time polymerase chain reaction or western blot. IL-1β-induced injury was investigated by cell viability, apoptosis, autophagy and inflammatory response using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide, flow cytometry, western blot and enzyme linked immunosorbent assay, respectively. The target association between miR-27b-3p and PVT1 or TRAF3 was explored by luciferase reporter, RNA immunoprecipitation and RNA pull-down assays. We found that PVT1 expression was enhanced in OA patients and IL-1β-treated C28/I2 cells. Silence of PVT1 promoted cell viability and autophagy but suppressed apoptosis and inflammatory response in IL-1β-treated C28/I2 cells. miR-27b-3p was confirmed as a target of PVT1 and its deficiency reversed the suppressive effect of PVT1 knockdown on IL-1β-induced injury. TRAF3 was a target of miR-27b-3p and attenuated the effect of miR-27b-3p on IL-1β-induced injury in C28/I2 cells. Moreover, TRAF3 expression was positively regulated by PVT1 via sponging miR-27b-3p. Collectively, knockdown of PVT1 increased cell viability and autophagy but inhibited apoptosis and inflammatory response in chondrocytes treated by IL-1β via up-regulating miR-27b-3p and down-regulating TRAF3.     

Continentalic acid exhibited nephroprotective activity against the LPS and E. coli-induced kidney injury through inhibition of the oxidative stress and inflammation

The present study investigated the effect of the continentalic acid (CNT) isolated from the Aralia Continentalis against the LPS and E. coli-induced nephrotoxicity. The LPS and E. coli administration markedly altered the behavioral parameters including spontaneous pain, tail suspension and survival rate. However, the treatment with CNT dose dependently improved the behavioral parameters. The CNT treatment significantly improved the renal functions test (RFTs) and hematological parameters following LPS and E. coli-induced kidney injury. Furthermore, the LPS and E. coli administration markedly compromised the anti-oxidant enzymes and enhanced the oxidative stress markers. However, the CNT treatment markedly enhanced the anti-oxidants enzymes such as GSH, GST, Catalase and SOD, while attenuated the oxidative stress markers such as MDA and POD. The MPO enzyme is widely used marker for the neutrophilic infiltration, the LPS and E. coli administration markedly increased the MPO activity. However, the CNT treatment markedly attenuated the MPO activity in both LPS and E. coli-induced kidney injury. Furthermore, the CNT treatment markedly attenuated the NO production compared to the LPS and E. coli-induced kidney injury group. Additionally, the CNT treatment improved the histological parameters markedly (H and E, PAS and Masson’s trichome staining) and protect the kidney from the inflammatory insult of the LPS and E. coli evidently. The comet assay revealed marked DNA damage, however, the CNT treatment markedly prevented the LPS and E. coli-induced kidney damage. The CNT treatment markedly enhanced the expression of Nrf2, while attenuated the iNOS expression in both models of kidney injury.     

Effects of sildenafil on inflammatory injury of the lung in sodium taurocholate-induced severe acute pancreatitis rats

BackgroundInflammatory response and acute lung injury (ALI) occur in sodium taurocholate-induced severe acute pancreatitis (SAP). Because sildenafil has anti-inflammatory, anti-oxidant and immune-modulating effects, we investigated its effect on inflammatory and lung injury in sodium taurocholate-induced SAP-associated ALI rat lung.MethodsSodium taurocholate-induced SAP rats received sildenafil (100 mg/kg) or not and were compared to age-matched normal control animals. We evaluated inflammatory response by detecting the expression of inflammatory factors including IL-1β, IL-6 and TNF-α, and detected the level of lung injury through histopathological evaluation. Moreover, we also tested the protein expression of PCNA, P21, Bcl-2 and Bax in the lung.ResultsSildenafil administration rats had a low level of lung injury and inflammation. In addition, sildenafil significantly increased the expression of proliferation-related markers and decreased the expression of apoptosis-related markers in lung tissue.ConclusionsSildenafil administration may attenuate inflammation and lung injury by promoting proliferation and suppressing apoptosis in SAP rats.     

Cilastatin protects against imipenem-induced nephrotoxicity via inhibition of renal organic anion transporters (OATs)

Imipenem is a carbapenem antibiotic. However, Imipenem could not be marketed owing to its instability and nephrotoxicity until cilastatin, an inhibitor of renal dehydropeptidase-I (DHP-I), was developed. In present study, the potential roles of renal organic anion transporters (OATs) in alleviating the nephrotoxicity of imipenem by cilastatin were investigated in vitro and in rabbits. Our results indicated that imipenem and cilastatin were substrates of hOAT1 and hOAT3. Cilastatin inhibited hOAT1/3-mediated transport of imipenem with IC₅₀ values comparable to the clinical concentration, suggesting the potential to cause a clinical drug–drug interaction (DDI). Moreover, imipenem exhibited hOAT1/3-dependent cytotoxicity, which was alleviated by cilastatin and probenecid. Furthermore, cilastatin and probenecid ameliorated imipenem-induced rabbit acute kidney injury, and reduced the renal secretion of imipenem. Cilastatin and probenecid inhibited intracellular accumulation of imipenem and sequentially decreased the nephrocyte toxicity in rabbit primary proximal tubule cells. Renal OATs, besides DHP-I, was also the target of interaction between imipenem and cilastatin, and contributed to the nephrotoxicity of imipenem. This therefore gives in part the explanation about the mechanism by which cilastatin protected against imipenem-induced nephrotoxicity. Thus, OATs can potentially be used as a therapeutic target to avoid the renal adverse reaction of imipenem in clinic.     

ACTH4-10 protects the ADR-injured podocytes by stimulating B lymphocytes to secrete interleukin-10

ObjectivesIn the present study, we aimed to assess whether adrenocorticotropic hormone (ACTH) could protect the podocytes from adriamycin (ADR)-induced injury by stimulating B lymphocytes to secrete the associated cytokines.MethodsProliferation assay was used to assess the proliferation and activity of podocytes. Enzyme-linked immunosorbent assay was used to examine the secretion of IL-10 and IL-4. TUNEL apoptosis detection kit was used to detect the apoptosis of podocytes. Real-time PCR and Western blotting analysis were used to examine the expressions of nephrin and podocin at the mRNA and protein levels.ResultsCompared with the normal control group, the podocyte proliferation of ADR group was significantly inhibited. However, compared with the ADR group, the podocyte proliferation of the supernatant (1 µg/L, 10 µg/L or 100 µg/L ACTH_4-10) + ADR groups was generally increased, and the pro-proliferative effect of the supernatant containing 10 µg/L ACTH_4-10 was the highest. Moreover, we found that after B lymphocytes were intervened by 10 µg/L ACTH4-10, the IL-10 level in the cell supernatant was significantly elevated (p < 0.05). When anti-IL-10R was added, the podocyte proliferation of the supernatant (10 µg/L ACTH_4-10) + ADR group was significantly inhibited. Furthermore, the supernatant of B cells stimulated with 10 µg/L ACTH_4-10 could better decrease the apoptosis rate of injured podocytes and increase the expressions of nephrin and podocin at the mRNA and protein levels by elevating the secretion of IL-10.ConclusionCompared with ACTH_4-10, the supernatant of B cells stimulated with ACTH_4-10 could better protect the podocytes from ADR-induced injury by elevating the secretion of IL-10.     

2-Dodecyl-6-methoxycyclohexa-2,5-diene-1,4-dione,isolated from the root of Averrhoa carambola L., protects against diabetic kidney disease by inhibiting TLR4/TGFβ signaling pathway

ObjectiveDiabetic kidney disease (DKD) is the leading cause of death and disability of diabetes mellitus. However, there is still a lack of specific drugs for the treatment of DKD. The chief aim of this research is to investigate the role and mechanism of 2-Dodecyl-6-methoxycyclohexa-2,5-diene-1,4-dione (DMDD) for DKD.MethodsWild type and TLR4 knockout mice were induced to diabetes. After 4-week treatment with DMDD, blood sugar, renal function, blood lipid and pathological changes were assessed. Real-time PCR, western blotting, and immunohistochemistry were employed to detect the expressions of TLR4, TGFβ1 and Smad2/3 in the renal tissue.ResultsDMDD improved the serum lipid and decreased fasting blood glucose levels in diabetic mice. CysC and urinary albumin levels increased markedly in the diabetic group, and they were obviously decreased after 4 weeks of DMDD treatment. Compared with the WT diabetic mice, the urinary albumin and CysC in the TLR4^-/- mice were expressed at lower levels. HE and Masson’s staining revealed that DMDD clearly ameliorated pathological changes and renal fibrosis. When TLR4 gene was knock out, the pathological was improved. Mechanistically, TLR4, TGF-β1 and Smad2/3 were obvious up-regulation in the renal tissues of diabetic mice. The expressions of these proteins were significantly down-regulated after DMDD treatment (p < 0.05). In the TLR4^-/- mice, mRNA and protein levels of TGF-β1 and Smad2/3 were obviously lower than those in the WT mice. In addition, IHC revealed that a strong in situ expressions of TLR4, TGF-β1 and Smad2/3 were seen in the kidney tissues of diabetic mice, which were distinctly weakened in the DMDD-treated mice. In the TLR4^-/- mice, however, expressions of TGF-β1 and Smad2/3 were not remarkable increase in the diabetic mice compared with normal mice.ConclusionsThese results strongly indicate that TLR4 is essential for DMDD protection against renal dysfunction in diabetic mice. Its hypoglycemic and anti-fibrosis effects were likely mediated by the TLR4/TGFβ signaling pathway.     

ISO-alpha-acids improve the hematoma resolution and prevent peri-hematoma inflammations by transforming microglia via PPARgamma-CD36 axis in ICH rats

ObjectiveTo elucidate the effects of ISO-α-acids (IAAs), a PPAR-γ agonist, on ICH rats and its potential mechanism.Material and methodsThe Sprague Dawley rats ICH model was induced by stereotactic injecting of 100 μl autologous artery blood. Ninety male rats were randomly allocated to five groups: autologous blood and IAAs (IAA); received autologous blood, IAAs and PPAR-γ inhibitor (IAA + GW9662); autologous blood and normal Saline (Saline); only autologous blood (Mock); and only needle injection (Sham). Neurological functions were assessed by mNSS. Hematoma volume, brain water content, surface proteins and inflammatory factors were detected. The microglia anti-inflammatory abilities were also evaluated.ResultsIAAs were able to significantly decrease ICH rat’s mNSS scores, alleviate brain water content, improve hematoma resolution than Saline, Mock (p < 0.05). More “M2” microglial/macrophage can be induced by IAAs. The expression of CD 36 was statistically higher in IAA than other groups (p < 0.05). Injection of IAAs led to a greatly increasing in CD 11b and CD 206 double-positive anti-inflammatory type microglial/macrophage, moreover, a reduction of inflammatory cytokines expression (p < 0.05). Such protective effects can be relieved by GW9662.ConclusionsThis is the first study to elucidate the relationship between IAAs and ICH. IAAs were able to accelerate hematoma absorption, alleviate brain edema, suppress peri-hematoma inflammations and finally improved the outcome of ICH rats. The phenotype was due to the IAAs induction of “M2” microglial/macrophage via activating of PPAR-γ and increasing CD 36 expression.     

IFN regulatory Factor-1 induced macrophage pyroptosis by modulating m6A modification of circ_0029589 in patients with acute coronary syndrome

BackgroundPyroptosis is identified as a novel form of inflammatory programmed cell death and has been recently found to be closely related to atherosclerosis (AS). We found that IFN regulatory factor-1(IRF-1) effectively promotes macrophage pyroptosis in patients with acute coronary syndrome (ACS). Subsequent studies have demonstrated that circRNAs are implicated in AS. However, the underlying mechanisms of circRNAs in macrophage pyroptosis remain elusive.MethodsWe detected the RNA expression of hsa_circ_0002984, hsa_circ_0010283 and hsa_circ_0029589 in human PBMC-derived macrophages from patients with coronary artery disease (CAD). The lentiviral recombinant vector for hsa_circ_0029589 overexpression (pLC5-GFP-circ_0029589) and small interference RNAs targeting hsa_circ_0029589 and METTL3 were constructed. Then, macrophages were transfected with pLC5-GFP-circ_0029589, si-circ_0029589 or si-METTL3 after IRF-1 was overexpressed and to explore the potential mechanism of hsa_circ_0029589 involved in IRF-1 induced macrophage pyroptosis.ResultsThe relative RNA expression level of hsa_circ_0029589 in macrophages was decreased, whereas the N6-methyladenosine (m6A) level of hsa_circ_0029589 and the expression of m6A methyltransferase METTL3 were validated to be significantly elevated in macrophages in patients with ACS. Furthermore, overexpression of IRF-1 suppressed the expression of hsa_circ_0029589, but induced its m6A level along with the expression of METTL3 in macrophages. Additionally, either overexpression of hsa_circ_0029589 or inhibition of METTL3 significantly increased the expression of hsa_circ_0029589 and attenuated macrophage pyroptosis.ConclusionOur observations suggest a novel mechanism by which IRF-1 facilitates macrophage pyroptosis and inflammation in ACS and AS by inhibiting circ_0029589 through promoting its m6A modification.     

Hepatoprotective activity of depsidone enriched Cladonia rangiferina extract against alcohol-induced hepatotoxicity targeting cytochrome P450 2E1 induced oxidative damage

Alcoholic liver disease (ALD) is a broad-spectrum disorder, covering fatty liver, cirrhosis, alcoholic hepatitis and in extreme untreated condition hepatocellular carcinoma (HCC) may also develop. Cladonia rangiferina (CR) is a class of lichen having a broad spectrum of pharmacological activity. It is used like traditional natural sources in ancient times in India, China, Sri Lanka, etc. Folkloric record about CR has reported their use as an antimicrobial, antitumor, antioxidant, anti-inflammatory activities, etc. Hence, the present study was requested to ascertain the effect of the ethanolic extract of Cladonia rangiferina (CRE) on alcohol-induced hepatotoxicity. The animals were evaluated for the estimation of the liver in vivo biochemical antioxidant parameters. The liver tissues were further evaluated histopathologically and western blotting examination for localization of apoptotic gene expression that plays a pivotal role in hepatotoxicity. The results of this study reveal that CRE proves to be helpful in the treatment of alcohol-induced hepatotoxicity and oxidative stress. Results of different markers have shown that among all, CRE has demonstrated the best hepatoprotective activity. These observations say about the importance of the components of the extract. The ameliorative action of CRE in alcoholic liver damage may exist due to antioxidant, anti-inflammatory, and anti-apoptotic activities.     

Novel compound FLZ alleviates rotenone-induced PD mouse model by suppressing TLR4/MyD88/NF-κB pathway through microbiota–gut–brain axis

Parkinson's disease (PD) is the second most common neurodegenerative disease, but none of the current treatments for PD can halt the progress of the disease due to the limited understanding of the pathogenesis. In PD development, the communication between the brain and the gastrointestinal system influenced by gut microbiota is known as microbiota–gut–brain axis. However, the explicit mechanisms of microbiota dysbiosis in PD development have not been well elucidated yet. FLZ, a novel squamosamide derivative, has been proved to be effective in many PD models and is undergoing the phase I clinical trial to treat PD in China. Moreover, our previous pharmacokinetic study revealed that gut microbiota could regulate the absorption of FLZ in vivo. The aims of our study were to assess the protective effects of FLZ treatment on PD and to further explore the underlying microbiota-related mechanisms of PD by using FLZ as a tool. In the current study, chronic oral administration of rotenone was utilized to induce a mouse model to mimic the pathological process of PD. Here we revealed that FLZ treatment alleviated gastrointestinal dysfunctions, motor symptoms, and dopaminergic neuron death in rotenone-challenged mice. 16S rRNA sequencing found that PD-related microbiota alterations induced by rotenone were reversed by FLZ treatment. Remarkably, FLZ administration attenuated intestinal inflammation and gut barrier destruction, which subsequently inhibited systemic inflammation. Eventually, FLZ treatment restored blood–brain barrier structure and suppressed neuroinflammation by inhibiting the activation of astrocytes and microglia in the substantia nigra (SN). Further mechanistic research demonstrated that FLZ treatment suppressed the TLR4/MyD88/NF-κB pathway both in the SN and colon. Collectively, FLZ treatment ameliorates microbiota dysbiosis to protect the PD model via inhibiting TLR4 pathway, which contributes to one of the underlying mechanisms beneath its neuroprotective effects. Our research also supports the importance of microbiota–gut–brain axis in PD pathogenesis, suggesting its potential role as a novel therapeutic target for PD treatment.