Hepatoprotective effects of paeonol by suppressing hepatic stellate cell activation via inhibition of SMAD2/3 and STAT3 pathways.

Hepatic stellate cell (HSC) activation is a key event in extracellular matrix accumulation, causing hepatic fibrosis. Therefore, identifying chemicals that inhibit HSC activation is an important therapeutic strategy for hepatic fibrosis. The aim of this study was to investigate the therapeutic effects of paeonol on HSC activation. In LX-2 cells, paeonol inhibited the expression of collagen and decreased the expression of HSC activation markers. In mice with thioacetamide-induced liver fibrosis, paeonol treatment decreased the serum levels of aspartate aminotransferase and alanine transaminase and mRNA expression of α-smooth muscle actin, platelet-derived growth factor-ß, and connective-tissue growth factor. Investigation of the underlying molecular mechanism of paeonol showed that paeonol inhibits the SMAD2/3 and STAT3 signaling pathways that are important for HSC activation. On the basis of these results, paeonol should be investigated and developed further for hepatic fibrosis treatment. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01440-9.

Correction to: Fis1 depletion in osteoarthritis impairs chondrocyte survival and peroxisomal and lysosomal function.

In Fig. 1C, the wrong si-control image was used by mistake.

Correction: HIF-1α:CRAT:miR-144-3p axis dysregulation promotes osteoarthritis chondrocyte apoptosis and VLCFA accumulation.

[This corrects the article DOI: 10.18632/oncotarget.20615.].

HIF-1α:CRAT:miR-144-3p axis dysregulation promotes osteoarthritis chondrocyte apoptosis and VLCFA accumulation.

The functional role(s) of peroxisomes in osteoarthritis remains unclear. We demonstrated that peroxisomal dysfunction in osteoarthritis is responsible for very-long-chain fatty acid (VLCFA) accumulation. Through gene-profiling analyses, we identified CRAT as the gene responsible for this event. CRAT expression was suppressed in osteoarthritis chondrocytes, and its knockdown yielded pathological osteoarthritic characteristics, including VLCFA accumulation, apoptosis, autophagic inhibition, and mitochondrial dysfunction. Subsequent miRNA profiling revealed that peroxisomal dysfunction upregulates miR-144-3p, which overlapped with the osteoarthritis pathological characteristics observed upon CRAT knockdown. Moreover, knocking down HIF-1α in normal chondrocytes suppressed CRAT expression while stimulating miR-144-3p. Our data indicate that deregulation of a HIF-1a:CRAT:miR-144-3p axis impairs peroxisomal function during the pathogenesis of osteoarthritis.

Fis1 depletion in osteoarthritis impairs chondrocyte survival and peroxisomal and lysosomal function.

Cumulative evidence suggests the importance of organelle homeostasis in regulating metabolic functions in response to various cellular stresses. Particularly, the dynamism and health of the mitochondria-peroxisome network through fission and fusion are essential for cellular function; dysfunctional dynamism underlies the pathogenesis of several degenerative diseases including Parkinson's disease. Here, we investigated the role of Fis1 in cartilage homeostasis and its relevance to osteoarthritis (OA). We found that Fis1 is significantly suppressed in human OA chondrocytes compared to that in normal chondrocytes. Fis1 depletion through siRNA induced peroxisomal dysfunction. Moreover, Fis1 suppression altered miRNA profiles, especially those implicated in lysosomal regulation. Lysosomal destruction using LAMP-1-specific targeted nanorods or lysosomal dysfunction through chloroquine treatment resulted in enhanced chondrocyte apoptosis and/or suppression of autophagy. Accordingly, lysosomal activity and autophagy were severely decreased in OA chondrocytes despite abundant LAMP-1-positive organelles. Moreover, Fis1 morpholino-injected zebrafish embryos displayed lysosome accumulation, mitochondrial dysfunction, and peroxisome reduction. Collectively, these data suggest interconnected links among Fis1-modulated miRNA, lysosomes, and autophagy, which contributes to chondrocyte survival/apoptosis. This study represents the first functional study of Fis1 with its pathological relevance to OA. Our data suggest a new target for controlling cartilage-degenerative diseases, such as OA. KEY MESSAGE: Fis1 suppression in OA chondrocytes induces accumulation and inhibition of lysosomes. Fis1 suppression alters miRNAs, especially those implicated in lysosomal regulation. Lysosomal destruction results in chondrocyte apoptosis and suppression of autophagy. Fis1 depletion in zebrafish causes lysosome accumulation, mitochondrial dysfunction, and peroxisome reduction. This is the first functional study of Fis1 and its pathological relevance to OA.

PCGEM1 stimulates proliferation of osteoarthritic synoviocytes by acting as a sponge for miR-770.

Long non-coding RNAs (lncRNAs) have been reported to play important roles in cellular metabolism and development. Various diseases have been associated with aberrant expression of lncRNAs and the related dysregulation of mRNAs. An lncRNA profiling assay was carried out to identify the key lncRNA in osteoarthritic human synoviocytes; the results revealed that prostate cancer gene expression marker 1 (PCGEM1) was significantly overexpressed in osteoarthritic synoviocytes. Exogenous overexpression of PCGEM1 inhibited apoptosis, induced autophagy, and stimulated the proliferation of human synoviocytes. The increased expression of PCGEM1 in human synoviocytes also suppressed the expression of miR-770. Transfection of the miR-770 precursor resulted in reduced proliferation, and induced apoptosis of human synoviocytes. This effect of miR-770 expression was reversed by co-introduction of PCGEM1. Target validation showed a direct binding between PCGEM1 and miR-770. We demonstrate that PCGEM1 act as sponge lncRNA for miR-770 that regulates proliferation/apoptosis and autophagy, and suggest PCGEM1 as possible target for OA therapy.

Beneficial reward-to-risk action of glucosamine during pathogenesis of osteoarthritis.

OBJECTIVE: Glucosamine is widely used to improve the symptoms and to delay the structural progression of osteoarthritis. However, its efficacy in osteoarthritis has been controversial and its underlying mechanism of action remains unclear. The aim of this study was to investigate the effects of glucosamine and the underlying mechanisms in human chondrocytes. METHODS: Chondrocytes from normal human articular cartilage were treated with glucosamine (10-100 mM). Subsequently, cell death was analyzed by Annexin V staining and FACS and mitochondrial function was studied by measuring the mitopotential. Peroxisomal function was analyzed by BODIPY staining, and gene expression of PMP70 and acyl-CoA oxidase 1, by real-time PCR. Total lipids were analyzed by gas chromatography/mass spectrometry. Autophagy activation was determined by western blotting of beclin and light chain 3B. Autophagosome formation was analyzed by introduction of green fluorescent protein (GFP) LC3, and pexophagy was determined by introduction of mRFP-EGFP-SKL plasmids. RESULTS: Treatment of chondrocytes with glucosamine exerts exposure time-dependent dual effects on apoptosis/autophagy. Short time exposure of glucosamine to chondrocytes activated autophagy, pexophagy, and peroxidation. On the other hand, long time exposure of glucosamine had opposite effects, namely accumulation of very long chain fatty acids and peroxisomal dysfunction. CONCLUSION: We highlight the dual role of glucosamine in apoptosis/autophagy in human chondrocytes depending on exposure time. Although further research is required to fully understand the dual effects of glucosamine, dosage and duration of glucosamine treatment are clear contributing factors towards the line of beneficial reward-to-risk action.

Down-regulation of Phospholipase D Stimulates Death of Lung Cancer Cells Involving Up-regulation of the Long ncRNA ANRIL.

Dysregulation of phospholipase D (PLD) has been found in several types of human cancer, but the underlying regulatory mechanism remains poorly-understood. Herein we found PLD inhibition in human H460 lung cancer cells has anti-tumorigenic effects such as stimulation of apoptosis and autophagy. In the present study, in order to identify the responsible key regulator of these anti-tumorigenic effects of PLD inhibition, we analyzed the expression levels of 90 long non-coding RNAs (lncRNAs). Among them, the expression level of antisense noncoding RNA in the INK4 locus (ANRIL) was increased up to 13.6-fold by PLD inhibition in H460 human lung cancer cells. Moreover, knockdown of ANRIL using its specific small-interfering RNA significantly suppressed PLD inhibition-induced apoptosis. Collectively, our findings showed that ANRIL is an lncRNA responsible in anti-tumorigenesis caused by PLD inhibition and combined incorporation of ANRIL into PLD inhibition-induced anti-tumorigenic signaling network could be a new effective therapeutic approach for controlling lung cancer.

Cluster of serogroup W-135 meningococcal disease in 3 military recruits.

We describe a group of 3 cases of invasive meningococcal disease that occurred in a military training camp in April 2011. All three patients were hospitalized. Ultimately, two patients recovered and one died. One patient had meningitis, one patient had septicemia and meningitis, and the other had no definite septicemia or meningitis. Neisseria meningitidis serogroup W-135 was detected in the serum and cerebrospinal fluid (CSF) of all patients by real-time polymerase chain reaction. In the one case of mortality, two strains were isolated from the patient's blood and CSF. Using multilocus sequence typing analysis, these strains were identified as a novel sequence type, ST-8912. Special attention is required for the meningococcal disease in military camp because the military personnels are in high risk of contact transmission.

Epidemics of Norovirus GII.4 Variant in Outbreak Cases in Korea, 2004-2012.

Norovirus GII.4 is recognized as a worldwide cause of nonbacterial outbreaks. In particular, the GII.4 variant occurs every 2-3 years according to antigenic variation. The aim of our study was to identify GII.4 variants in outbreaks in Korea during 2004-2012. Partial VP1 sequence of norovirus GII.4-related outbreaks during 2004-2012 was analyzed. The partial VP1 sequence was detected with reverse transcription-polymerase chain reaction, seminested polymerase chain reaction, and nucleotide sequence of 312-314 base pairs for phylogenetic comparison. Nine variants emerged in outbreaks, with the Sydney variant showing predominance recently. This predominance may persist for at least 3 years, although new variants may appear in Korea.

Occurrence of Norovirus GII.4 Sydney Variant-related Outbreaks in Korea.

Human noroviruses are major causative agents of food and waterborne outbreaks of nonbacterial acute gastroenteritis. In this study, we report the epidemiological features of three outbreak cases of norovirus in Korea, and we describe the clinical symptoms and distribution of the causative genotypes. The incidence rates of the three outbreaks were 16.24% (326/2,007), 4.1% (27/656), and 16.8% (36/214), respectively. The patients in these three outbreaks were affected by acute gastroenteritis. These schools were provided unheated food from the same manufacturing company. Two genotypes (GII.3 and GII.4) of the norovirus were detected in these cases. Among them, major causative strains of GII.4 (Hu-jeju-47-2007KR-like) were identified in patients, food handlers, and groundwater from the manufacturing company of the unheated food. In the GII.4 (Hu-jeju-47-2007KR-like) strain of the norovirus, the nucleotide sequences were identical and identified as the GII.4 Sydney variant. Our data suggests that the combined epidemiological and laboratory results were closely related, and the causative pathogen was the GII.4 Sydney variant strain from contaminated groundwater.

Complete nucleotide sequence of the IncI1 plasmid pSH4469 encoding CTX-M-15 extended-spectrum ß-lactamase in a clinical isolate of Shigella sonnei from an outbreak in the Republic of Korea.

An outbreak of extended-spectrum ß-lactamase (ESBL)-producing Shigella sonnei infections occurred in a school for disabled children in Gyeongbuk Province, Republic of Korea, in 2008. Five students were affected. Pulsed-field gel electrophoresis (PFGE) analysis revealed that all of the ESBL-producing S. sonnei isolates belonged to the same clone, and nucleotide sequence analysis of ESBL genes revealed that they harboured bla(CTX-M-15). This is the first identification of bla(CTX-M-15) in Shigella spp. in South Korea. In this study, a plasmid carrying the bla(CTX-M-15) gene, designated pSH4469, recovered from a S. sonnei isolate responsible for the outbreak was characterised. Replicon typing and plasmid multilocus sequence typing (pMLST) analysis of plasmids in the outbreak strain identified that the bla(CTX-M-15) gene was located on an IncI1 incompatibility group plasmid of sequence type 16 (ST16). The complete nucleotide sequence of pSH4469 revealed that this plasmid is 91109bp and harbours 119 putative genes, including another antibiotic resistance gene (bla(TEM-1b)) that is often associated with the ISEcp1-bla(CTX-M-15)-orf477delta transposable unit. The plasmid consists of a large backbone with considerable homology to the pEK204 plasmid isolated from Escherichia coli in the UK, except for insertion of an IS66 element found in pEK204. These data demonstrate that IncI1 plasmids are used as a successful platform for efficient horizontal gene transfer, thereby resulting in the dissemination of CTX-M-type ß-lactamases among Enterobacteriaceae.

Genetic diversity of Campylobacter jejuni isolates from Korea and travel-associated cases from east and southeast Asian countries.

Forty domestic and travel-associated Campylobacter jejuni isolates were analyzed by profiling 7 pathogenic genes (cdtB, cadF, Cj0131, ciaB, racR, wlaN, and virB11) along with multilocus sequence typing (MLST) and antimicrobial susceptibility testing. cdtB, cadF, and Cj0131 were present in all isolates, whereas virB11 was not detected in either domestic or travel-associated isolates. ciaB was present in all domestic isolates and 94% of travel-associated isolates. The respective detection rates of racR and wlaN in domestic and travel-associated isolates were 94% and 71% and 35.3% and 23%, respectively. MLST analyses of the 40 isolates generated 25 different sequence types (STs). ST-443 (12 isolates) and ST-21 (8 isolates) were dominant among the domestic isolates; however, STs varied among travel-associated isolates. Nalidixic acid, tetracycline, and ciprofloxacin resistance rates of the 40 isolates were 100% (40/40), 95% (38/40), and 88% (35/40), respectively. Domestic isolates exhibited 2-fold higher ciprofloxacin, telithromycin, and chloramphenicol resistance rates than travel-associated isolates. These results indicate a diverse genetic background for travel-associated C. jejuni and suggest that this pathogen may be an important emerging public health threat to travelers.

Possibility of CTX-M-14 Gene Transfer from Shigella sonnei to a Commensal Escherichia coli Strain of the Gastroenteritis Microbiome.

OBJECTIVES: To investigated whether the CTX-M-14 gene could be transferred from a clinical Shigella sonnei strain to commensal Escherichia coli strain in the gastroenteritis microbiome. METHODS: E. coli strains were isolated from 30 stool samples of S. sonnei infected students in a gastroenteritis outbreak in 2004 and were characterized by antibiotic resistance analysis, in vitro conjugation and in vivo transfer of CTX-M-14 gene and molecular assays. RESULTS: One strain of Escherichia coli that had high levels of resistance to cefotaxime was isolated from a patient infected with S. sonnei. Isoelectric focusing showed that the E. coli and S. sonnei strains produced a ß-lactamase with an isoelectric point of 8.1. Moreover, polymerase chain reaction analysis indicated that both strains possessed the same DNA sequences for CTX-M-14. The results of in vitro and in vivo conjugation showed that the efficiency of CTX-M-14 transfer from S. sonnei to E. coli was similar to CTX-M-14 transfer between E. coli strains. CONCLUSION: The data suggest that the acquisition of the extended-spectrum ß-lactamases gene by pathogenic bacteria in the human intestinal tract to commensal microbiome bacteria can cause serious infectious diseases.

Peroxisomal dysfunction is associated with up-regulation of apoptotic cell death via miR-223 induction in knee osteoarthritis patients with type 2 diabetes mellitus.

Recent increasing evidences showing the interconnection between mitochondria and peroxisome in performing metabolic functions imply that peroxisome dysfunction could lead to a wide variety of human diseases including cancer and osteoarthritis (OA) as mitochondria dysfunction. Even though there is a higher incidence and development of OA in diabetes mellitus (DM) patients, there is not much evidential mechanism study in this inter-regulation between OA and OA with DM in a new view of peroxisome. In this study, we analyzed the alteration of peroxisomal gene expression that could responsible for pathological difference between OA chondrocytes and OA/DM chondrocytes. To discriminate responsible genes in the OA/DM pathogenesis, the expressions of three hundred sixty-two genes reported to differentially relate to peroxisome were analyzed with OA chondrocytes in OA cartilage and OA/DM chondrocytes in the cartilage of OA with DM patient. Among them, PEX-16, a component of peroxisome, was significantly down-regulated in OA/DM chondrocytes and this down-regulation of PEX-16 increased the miR-223 induction. Knockdown studies using PEX-16 null cell line and PEX-16 specific siRNA showed the significant increase in apoptotic cell death. Moreover, over-expression of miR-223 stimulates apoptotic cell death in human articular chondrocytes and induced severe cartilage destruction in db/db mice. In conclusion, our study showed the differential peroxisomal gene expression profiles for OA/DM chondrocytes from OA chondrocytes and suggests the possibility that peroxisomal dysfunction in OA/DM could be responsible for early incidence and development of OA in DM patients.

Comparative proteomic label-free analysis of Campylobacter jejuni NCTC 11168 cultured with porcine mucin.

Campylobacter jejuni is a major gastrointestinal pathogen in humans. Poultry is a primary reservoir for C. jejuni, and C. jejuni appears to be highly adapted to the gastrointestinal tracts of avian species. We determined the protein expression profiles of C. jejuni NCTC 11168 cultured in medium containing porcine mucin. Differentially expressed proteins in the presence and absence of porcine mucin were identified using the label-free method. We identified 52 proteins with expression that was either upregulated (32 proteins) or downregulated (20 proteins) by porcine mucin. These proteins are involved in diverse cellular functions, such as motility, cell wall synthesis, iron transport, energy production, and amino acid metabolism. In particular, the upregulated proteins were involved in chemotaxis (CheV and CetA), motility (FlaA), colonization and adherence (CadF, FrdA, CfrA, MapA, and HydA), and stress tolerance (TrxB and ClpB). These results suggest that C. jejuni changes its protein expression in response to porcine mucin and that this change in expression may contribute to host adaptation of C. jejuni NCTC 11168.

Characterization of CTX-M-type extended-spectrum beta-lactamase-producing diarrheagenic Escherichia coli isolates in the Republic of Korea during 2008-2011.

To characterize the extended-spectrum beta-lactamases (ESBLs) in diarrheagenic Escherichia coli from Korea in 2008-2011, we screened seven enterotoxigenic E. coli (ETEC) and one enteroaggregative E. coli (EAEC) that produce ESBLs from a nationwide survey. All eight isolates produced CTX-M-type ESBLs, including CTX-M-12 (n = 4), CTX-M-14 (n = 2), and CTX-M-15 (n = 2). PCR-based replicon typing indicated that the blaCTX-M-12 genes of four ETEC isolates were carried on a conjugative IncF plasmid, whereas the blaCTX-M-14 of one EAEC was located on an IncK plasmid. This is the first report of the occurrence of blaCTX-M genes in clinical isolates of EAEC in Korea. The ESBL-producing isolates were shown to be different based on pulsed-field gel electrophoresis and multilocus sequence typing, whereas the four isolates with CTX-M-12 were clonally related. These observations raise an alarm for the spread of plasmid-mediated resistance to ESBL among diarrheagenic E. coli.