Correlation between short-chain fatty acids and peri-implant disease: A cross-sectional study.

BACKGROUND: To explore the correlation between short-chain fatty acids (SCFAs) in the peri-implant sulcular fluid (PISF) and peri-implant diseases. METHODS: PISF samples were obtained from implants that have been placed for at least 5 years, and peri-implant clinical parameters were examined. Gas chromatography-mass spectrometry and high-performance liquid chromatography were used to detect SCFAs in PISF. The correlation between SCFAs and clinical parameters was analyzed by Spearman's correlation. SCFAs related to peri-implant disease were identified by logistic regression and ranked by random forest analysis. RESULTS: Eighty-six implants were divided into a peri-implant health group (PIH-group, 35 implants), peri-implant mucositis group (PIM-group, 25 implants), and peri-implantitis group (PI-group, 26 implants) according to clinical and radiographic examination results. The PIM-group had significantly lower formic acid detection rate than the other two groups (p < 0.001). The PIM-group had significantly higher levels of acetic, propionic, and isovaleric acids than the PIH-group (p < 0.05). The PI-group had significantly higher levels of propionic, butyric, isobutyric, valeric, and isovaleric acids than the PIH-group (p < 0.05). The PI-group had significantly higher levels of butyric, isobutyric, and isovaleric acids than the PIM-group (p < 0.05). SCFAs (apart from hexanoic and succinic acids) were significantly and positively correlated with clinical parameters (p < 0.05). SCFAs related to peri-implant disease were ranked as follows: butyric, isovaleric, isobutyric, propionic, acetic, formic, and lactic acids. CONCLUSIONS: Elevated specific SCFAs are correlated with peri-implant disease. Recognition of this correlation may help in early identification of peri-implant disease and guide further clinical interventions.

circBRAF promotes the progression of triple-negative breast cancer through modulating methylation by recruiting KDM4B to histone H3K9me3 and IGF2BP3 to mRNA.

Understanding the molecular characteristics of triple-negative breast cancer (TNBC) and developing more tailored treatment approaches is crucial. Circular RNAs (circRNAs), as potential therapeutic targets, remain largely unexplored in TNBC. This study utilized circRNA microarray analysis to determine the expression of circRNAs in TNBC, analyzing nine patient specimens. The characteristics of circBRAF were examined using divergent PCR primers, Sanger sequencing, fluorescence in situ hybridization (FISH) analysis, and the application of RNase and actinomycin D. The biological function of circBRAF in TNBC was further investigated through colony formation, tube formation, and transwell assays. Crucially, the mechanisms underlying the effects of circBRAF on TNBC progression were explored via RNA immunoprecipitation sequencing (RIP-seq) data, MS2 pulldown, RNA sequencing (RNA-seq) analysis, circBRAF knockdown, histone H3K9me3 modification, and Chromatin Isolation by RNA Purification (ChIRP) tests followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). We focused particularly on hsa_circ_0007178, produced from exons 4-13 of the oncogene BRAF. Functional experiments revealed that circBRAF is crucial for the development of TNBC, with its knockdown preventing angiogenesis, metastasis, and cell division in vitro. Mechanistically, circBRAF interacts with KDM4B and IGF2BP3, promoting TNBC growth. Interaction of circBRAF with IGF2BP3 increased the expression of VCAN, FN1, CDCA3, or B4GALT3 by controlling mRNA stability through RNA N6-methyladenosine (m6A) modification. Furthermore, circBRAF upregulated the expression of ADAMTS14 and MMP9 through recruitment of KDM4B to enhance respective H3K9me3 modification. Furthermore, overexpression of circBRAF was able to overcome the inhibitory effects of siKDM4B and siIGF2BP3 on cell migration and invasion. Our findings suggest that circBRAF may act as an oncogene in TNBC through its specific interactions with KDM4B and IGF2BP3, implying that circBRAF could serve as a potentially effective novel therapeutic target for TNBC.

Ecological effect of microplastics on soil microbe-driven carbon circulation and greenhouse gas emission: A review.

Soil organic carbon (SOC) pool, the largest part of terrestrial ecosystem, controls global terrestrial carbon balance and consequently presented carbon cycle-climate feedback in climate projections. Microplastics, (MPs, <5 mm) as common pollutants in soil ecosystems, have an obvious impact on soil-borne carbon circulation by affecting soil microbial processes, which play a central role in regulating SOC conversion. In this review, we initially presented the sources, properties and ecological risks of MPs in soil ecosystem, and then the differentiated effects of MPs on the component of SOC, including dissolved organic carbon, soil microbial biomass carbon and easily oxidized organic carbon varying with the types and concentrations of MPs, the soil types, etc. As research turns into a broader perspective, greenhouse gas emissions dominated by the mineralization of SOC coming into view since it can be significantly affected by MPs and is closely associated with soil microbial respiration. The pathways of MPs impacting soil microbes-driven carbon conversion include changing microbial community structure and composition, the functional enzyme's activity and the abundance and expression of functional genes. However, numerous uncertainties still exist regarding the microbial mechanisms in the deeper biochemical process. More comprehensive studies are necessary to explore the affected footprint and provide guidance for finding the evaluation criterion of MPs affecting climate change.

AN698/40746067 suppresses bone marrow adiposity to ameliorate hyperlipidemia-induced osteoporosis through targeted inhibition of ENTR1.

Hyperlipidemia-induced osteoporosis is marked by increased bone marrow adiposity, and treatment with statins for hyperlipidemia often leads to new-onset osteoporosis. Endosome-associated trafficking regulator 1 (ENTR1) has been found to interact with different proteins in pathophysiology, but its exact role in adipogenesis is not yet understood. This research aimed to explore the role of ENTR1 in adipogenesis and to discover a new small molecule that targets ENTR1 for evaluating its effectiveness in treating hyperlipidemia-induced osteoporosis. We found that ENTR1 expression increased during the adipogenesis of bone marrow mesenchymal cells (BMSCs). ENTR1 gain- and loss-of-function assays significantly enhanced lipid droplets formation. Mechanistically, ENTR1 binds peroxisome proliferator-activated receptor γ (PPARγ) and enhances its expression, thereby elevating adipogenic markers including C/EBPα and LDLR. Therapeutically, AN698/40746067 attenuated adipogenesis by targeting ENTR1 to suppress PPARγ. In vivo, AN698/40746067 reduced bone marrow adiposity and bone loss, as well as prevented lipogenesis-related obesity, inflammation, steatohepatitis, and abnormal serum lipid levels during hyperlipidemia. Together, these findings suggest that ENTR1 facilitates adipogenesis by PPARγ involved in BMSCs' differentiation, and targeted inhibition of ENTR1 by AN698/40746067 may offer a promising therapy for addressing lipogenesis-related challenges and alleviating osteoporosis following hyperlipidemia.

Neuropeptide substance P attenuates colitis by suppressing inflammation and ferroptosis via the cGAS-STING signaling pathway.

Neuropeptide substance P (SP) belongs to a family of bioactive peptides and regulates many human diseases. This study aims to investigate the role and underlying mechanisms of SP in colitis. Here, activated SP-positive neurons and increased SP expression were observed in dextran sodium sulfate (DSS)-induced colitis lesions in mice. Administration of exogenous SP efficiently ameliorated the clinical symptoms, impaired intestinal barrier function, and inflammatory response. Mechanistically, SP protected mitochondria from damage caused by DSS or TNF-α exposure, preventing mitochondrial DNA (mtDNA) leakage into the cytoplasm, thereby inhibiting the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway. SP can also directly prevent STING phosphorylation through the neurokinin-1 receptor (NK1R), thereby inhibiting the activation of the TBK1-IRF3 signaling pathway. Further studies revealed that SP alleviated the DSS or TNF-α-induced ferroptosis process, which was associated with repressing the cGAS-STING signaling pathway. Notably, we identified that the NK1R inhibition reversed the effects of SP on inflammation and ferroptosis via the cGAS-STING pathway. Collectively, we unveil that SP attenuates inflammation and ferroptosis via suppressing the mtDNA-cGAS-STING or directly acting on the STING pathway, contributing to improving colitis in an NK1R-dependent manner. These findings provide a novel mechanism of SP regulating ulcerative colitis (UC) disease.

The African swine fever virus MGF300-4L protein is associated with viral pathogenicity by promoting the autophagic degradation of IKKß and increasing the stability of IκBα.

African swine fever (ASF) is a highly contagious, often fatal viral disease caused by African swine fever virus (ASFV), which imposes a substantial economic burden on the global pig industry. When screening for the virus replication-regulating genes in the left variable region of the ASFV genome, we observed a notable reduction in ASFV replication following the deletion of the MGF300-4L gene. However, the role of MGF300-4L in ASFV infection remains unexplored. In this study, we found that MGF300-4L could effectively inhibit the production of proinflammatory cytokines IL-1ß and TNF-α, which are regulated by the NF-κB signaling pathway. Mechanistically, we demonstrated that MGF300-4L interacts with IKKß and promotes its lysosomal degradation via the chaperone-mediated autophagy. Meanwhile, the interaction between MGF300-4L and IκBα competitively inhibits the binding of the E3 ligase ß-TrCP to IκBα, thereby inhibiting the ubiquitination-dependent degradation of IκBα. Remarkably, although ASFV encodes other inhibitors of NF-κB, the MGF300-4L gene-deleted ASFV (Del4L) showed reduced virulence in pigs, indicating that MGF300-4L plays a critical role in ASFV pathogenicity. Importantly, the attenuation of Del4L was associated with a significant increase in the production of IL-1ß and TNF-α early in the infection of pigs. Our findings provide insights into the functions of MGF300-4L in ASFV pathogenicity, suggesting that MGF300-4L could be a promising target for developing novel strategies and live attenuated vaccines against ASF.

rgpA-Engineered/Functionalized DNA Vaccine as a Novel Prophylactic Vaccination to Prevent Porphyromonas gingivalis-Induced Periodontitis: An in Vivo Study.

BACKGROUND: Arg-gingipain A (rgpA) and Arg-gingipain B (rgpB) are crucial virulence factors associated with Porphyromonas gingivalis (P. gingivalis) and have been recognized as promising targets for antibacterial vaccines. Although vaccines containing rgpA have shown efficacy, the incorporation of rgpB, which lacks the haemagglutinin adhesin (HA) domain, diminishes the vaccine's effectiveness. This study aims to assess the immunogenicity of the functional HA domain of rgpA in mouse periodontitis models. METHODS: A total of 24 mice were randomly divided into four groups, each receiving different immune injections: group A received phosphate-buffered saline (PBS) as an empty control; group B received pVAX1 as a negative control (NC); group C received pVAX1-HA; and group D received pVAX1-rgpA. The mice were subjected to intramuscular injections every two weeks for a total of three administrations. Prior to each immunization, blood samples were collected for antibody detection under isoflurane anesthesia. Following the final immunization, periodontitis was induced two weeks later by using sutures soaked in a P. gingivalis solution. The mice were euthanized after an additional two-week period. To assess the safety of the procedure, major organs were examined through hematoxylin-eosin (HE) staining. Subsequently, the levels of IgG, IgG1, and IgG2a in the serum were quantified via enzyme-linked immunosorbent assay (ELISA). Additionally, the expression of inflammatory factors in the gingiva, including interleukin-6 (IL-6), interleukin-1ß (IL-1ß), and tumor necrosis factor alpha (TNF-α), was determined using quantitative real-time reverse transcript PCR (qRT-PCR). The extent of bone loss in periodontal tissues was evaluated using micro-computed tomography (micro-CT) and HE staining. RESULTS: HE staining of the organs confirmed the absence of vaccine-induced toxicity in vivo. After the second immunization, both the rgpA and HA groups displayed significantly higher specific IgG titers in comparison to the NC and PBS groups (p < 0.05). Furthermore, the rgpA and HA groups exhibited a noteworthy predominance of IgG1 antibodies after three immunization doses, while there was a noticeable reduction in IgG2a levels observed following ligation with P. gingivalis sutures, as opposed to the NC and PBS groups (p < 0.05). Additionally, both the HA and rgpA groups showed a significant decrease in the expression of inflammatory factors such as IL-6, IL-1ß, and TNF-α, as well as a reduction in bone loss around periodontitis-affected teeth, when compared to the NC and PBS groups (p < 0.05). CONCLUSIONS: The results of this study demonstrate that the rgpA-engineered/functionalized HA gene vaccine is capable of eliciting a potent prophylactic immune response against P. gingivalis-induced periodontitis, effectively serving as an immunogenic and protective agent in vivo.

Apical papilla stem cell-derived exosomes regulate lipid metabolism and alleviate inflammation in the MCD-induced mouse NASH model.

Stem cells from the apical papilla(SCAPs) exhibit remarkable tissue repair capabilities, demonstrate anti-inflammatory and pro-angiogenic effects, positioning them as promising assets in the realm of regenerative medicine. Recently, the focus has shifted towards exosomes derived from stem cells, perceived as safer alternatives while retaining comparable physiological functions. This study delves into the therapeutic implications of exosomes derived from SCAPs in the methionine-choline-deficient (MCD) diet-induced mice non-alcoholic steatohepatitis (NASH) model. We extracted exosomes from SCAPs. During the last two weeks of the MCD diet, mice were intravenously administered SCAPs-derived exosomes at two distinct concentrations (50 µg/mouse and 100 µg/mouse) biweekly. Thorough examinations of physiological and biochemical indicators were performed to meticulously evaluate the impact of exosomes derived from SCAPs on the advancement of NASH in mice induced by MCD diet. This findings revealed significant reductions in body weight loss and liver damage induced by the MCD diet following exosomes treatment. Moreover, hepatic fat accumulation was notably alleviated. Mechanistically, the treatment with exosomes led to an upregulation of phosphorylated adenosine monophosphate-activated protein kinase (p-AMPK) levels in the liver, enhancing hepatic fatty acid oxidation and transporter gene expression while inhibiting genes associated with fatty acid synthesis. Additionally, exosomes treatment increased the transcription levels of key liver mitochondrial marker proteins and the essential mitochondrial biogenesis factor. Furthermore, the levels of serum inflammatory factors and hepatic tissue inflammatory factor mRNA expression were significantly reduced, likely due to the anti-inflammatory phenotype induced by exosomes in macrophages. The above conclusion suggests that SCAPs-exosomes can improve NASH.

N6-methyladenosine-modified circPLPP4 sustains cisplatin resistance in ovarian cancer cells via PIK3R1 upregulation.

BACKGROUND: Cisplatin (CDDP) is the first-line chemotherapeutic strategy to treat patients with ovarian cancer (OC). The development of CDDP resistance remains an unsurmountable obstacle in OC treatment and frequently induces tumor recurrence. Circular RNAs (circRNAs) are noncoding RNAs with important functions in cancer progression. Whether circRNAs function in CDDP resistance of OC is unclear. METHODS: Platinum-resistant circRNAs were screened via circRNA deep sequencing and examined using in situ hybridization (ISH) in OC. The role of circPLPP4 in CDDP resistance was assessed by clone formation and Annexin V assays in vitro, and by OC patient-derived xenografts and intraperitoneal tumor models in vivo. The mechanism underlying circPLPP4-mediated activation of miR-136/PIK3R1 signaling was examined by luciferase reporter assay, RNA pull-down, RIP, MeRIP and ISH. RESULTS: circPLPP4 was remarkably upregulated in platinum resistant OC. circPLPP4 overexpression significantly enhanced, whereas circPLPP4 silencing reduced, OC cell chemoresistance. Mechanistically, circPLPP4 acts as a microRNA sponge to sequester miR-136, thus competitively upregulating PIK3R1 expression and conferring CDDP resistance. The increased circPLPP4 level in CDDP-resistant cells was caused by increased RNA stability, mediated by increased N6-methyladenosine (m6A) modification of circPLPP4. In vivo delivery of an antisense oligonucleotide targeting circPLPP4 significantly enhanced CDDP efficacy in a tumor model. CONCLUSIONS: Our study reveals a plausible mechanism by which the m6A -induced circPLPP4/ miR-136/ PIK3R1 axis mediated CDDP resistance in OC, suggesting that circPLPP4 may serve as a promising therapeutic target against CDDP resistant OC. A circPLPP4-targeted drug in combination with CDDP might represent a rational regimen in OC.

Dissection of FOXO1-Induced LYPLAL1-DT Impeding Triple-Negative Breast Cancer Progression via Mediating hnRNPK/ß-Catenin Complex.

Triple-negative breast cancer (TNBC) is considered as the most hazardous subtype of breast cancer owing to its accelerated progression, enormous metastatic potential, and refractoriness to standard treatments. Long noncoding RNAs (lncRNAs) are extremely intricate in tumorigenesis and cancerous metastasis. Nonetheless, their roles in the initiation and augmentation of TNBC remain elusive. Here, in silico analysis and validation experiments were utilized to analyze the expression pattern of clinically effective lncRNAs in TNBC, among which a protective lncRNA LYPLAL1-DT was essentially curbed in TNBC samples and indicated a favorable prognosis. Gain- and loss-of-function assays elucidated that LYPLAL1-DT considerably attenuated the proliferative and metastatic properties along with epithelial-mesenchymal transition of TNBC cells. Moreover, forkhead box O1 (FOXO1) was validated to modulate the transcription of LYPLAL1-DT. Mechanistically, LYPLAL1-DT impinged on the malignancy of TNBC mainly by restraining the aberrant reactivation of the Wnt/ß-catenin signaling pathway, explicitly destabilizing and diminishing ß-catenin protein by interacting with heterogeneous nuclear ribonucleoprotein K (hnRNPK) and constricting the formation of the hnRNPK/ß-catenin complex. Conclusively, our present research revealed the anti-oncogenic effects of LYPLAL1-DT in TNBC, unraveling the molecular mechanisms of the FOXO1/LYPLAL1-DT/hnRNPK/ß-catenin signaling axis, which shed innovative light on the potential curative medicine of TNBC.

Contamination Status, Environmental Factor and Risk Assessment of Polychlorinated Biphenyls and Hexachlorobutadiene in Greenhouse and Open-Field Agricultural Soils across China.

With the popularization and high-intensity utilization of greenhouse cultivation for crops growth, the pollution of greenhouse soils has been of concern. Therefore, a national-scale survey was conducted to investigate the contamination status, sources, influence factors and the risks of polychlorinated biphenyls (PCBs) and hexachlorobutadiene (HCBD) in greenhouse and nearby open-field soils. Contents of PCBs ranged from 10-6). This study provided a full insight on the contamination status and risks of PCBs and HCBD when guiding greenhouse agriculture activities.

Prevention and treatment of hepatic encephalopathy during the perioperative period of transjugular intrahepatic portosystemic shunt.

Transjugular intrahepatic portosystemic shunt (TIPS) is an established procedure for treating the complications of portal hypertension in liver cirrhosis. While the pathogenesis of postoperative TIPS-related hepatic encephalopathy (HE) has yet to be fully understood, intraoperative portosystemic shunts may provide a pathological basis for the occurrence of postoperative HE in patients with liver cirrhosis. Studies at home and abroad have expressed mixed opinions about TIPS-related HE. This study presents a literature review on the risk factors for and prevention and treatment of perioperative TIPS-related HE in patients with liver cirrhosis, aiming to optimize the procedure and reduce the incidence of postoperative HE.

Characteristics of mesenchymal stem cells and their exosomes derived from giant panda (Ailuropoda melanoleuca) endometrium.

Conservation of genetic resources is an important way to protect endangered species. At present, mesenchymal stem cells (MSCs) have been isolated from the bone marrow and umbilical cords of giant pandas. However, the types and quantities of preserved cell resources were rare and limited, and none of MSCs was derived from female reproductive organs. Here, we first isolated MSCs from the endometrium of giant panda. These cells showed fibroblast morphology and expressed Sox2, Klf4, Thy1, CD73, CD105, CD44, CD49f, and CD105. Endometrium mesenchymal stem cells (eMSCs) of giant panda could induce differentiation into three germ layers in vitro. RNA-seq analysis showed that 833 genes were upregulated and 716 genes were downregulated in eMSCs compared with skin fibroblast cells. The results of GO and the KEGG analysis of differentially expressed genes (DEGs) were mainly focused on transporter activity, signal transducer activity, pathways regulating pluripotency of stem cells, MAPK signaling pathway, and PI3K-Akt signaling pathway. The genes PLCG2, FRK, JAK3, LYN, PIK3CB, JAK2, CBLB, and MET were identified as hub genes by PPI network analysis. In addition, the exosomes of eMSCs were also isolated and identified. The average diameter of exosomes was 74.26 ± 13.75 nm and highly expressed TSG101 and CD9 but did not express CALNEXIN. A total of 277 miRNAs were detected in the exosomes; the highest expression of miRNA was the has-miR-21-5p. A total of 14461 target genes of the whole miRNAs were predicted and proceeded with functional analysis. In conclusion, we successfully isolated and characterized the giant panda eMSCs and their exosomes, and analyzed their functions through bioinformatics techniques. It not only enriched the conservation types of giant panda cell resources and promoted the protection of genetic diversity, but also laid a foundation for the application of eMSCs and exosomes in the disease treatment of giant pandas.

The MGF300-2R protein of African swine fever virus is associated with viral pathogenicity by promoting the autophagic degradation of IKKα and IKKß through the recruitment of TOLLIP.

The multigene family genes (MGFs) in the left variable region (LVR) of the African swine fever virus (ASFV) genome have been reported to be involved in viral replication in primary porcine alveolar macrophages (PAMs) and virulence in pigs. However, the exact functions of key MGFs in the LVR that regulate the replication and virulence of ASFV remain unclear. In this study, we identified the MGF300-2R gene to be critical for viral replication in PAMs by deleting different sets of MGFs in the LVR from the highly virulent strain ASFV HLJ/18 (ASFV-WT). The ASFV mutant lacking the MGF300-2R gene (Del2R) showed a 1-log reduction in viral titer, and induced higher IL-1ß and TNF-α production in PAMs than did ASFV-WT. Mechanistically, the MGF300-2R protein was found to interact with and degrade IKKα and IKKß via the selective autophagy pathway. Furthermore, we showed that MGF300-2R promoted the K27-linked polyubiquitination of IKKα and IKKß, which subsequently served as a recognition signal for the cargo receptor TOLLIP-mediated selective autophagic degradation. Importantly, Del2R exhibited a significant reduction in both replication and virulence compared with ASFV-WT in pigs, likely due to the increased IL-1ß and TNF-α, indicating that MGF300-2R is a virulence determinant. These findings reveal that MGF300-2R suppresses host innate immune responses by mediating the degradation of IKKα and IKKß, which provides clues to paving the way for the rational design of live attenuated vaccines to control ASF.

The Aldose Reductase Inhibitor Epalrestat Maintains Blood-Brain Barrier Integrity by Enhancing Endothelial Cell Function during Cerebral Ischemia.

Excessive activation of aldose reductase (AR) in the brain is a risk factor for aggravating cerebral ischemia injury. Epalrestat is the only AR inhibitor with proven safety and efficacy, which is used in the clinical treatment of diabetic neuropathy. However, the molecular mechanisms underlying the neuroprotection of epalrestat remain unknown in the ischemic brain. Recent studies have found that blood-brain barrier (BBB) damage was mainly caused by increased apoptosis and autophagy of brain microvascular endothelial cells (BMVECs) and decreased expression of tight junction proteins. Thus, we hypothesized that the protective effect of epalrestat is mainly related to regulating the survival of BMVECs and tight junction protein levels after cerebral ischemia. To test this hypothesis, a mouse model of cerebral ischemia was established by permanent middle cerebral artery ligation (pMCAL), and the mice were treated with epalrestat or saline as a control. Epalrestat reduced the ischemic volume, enhanced BBB function, and improved the neurobehavior after cerebral ischemia. In vitro studies revealed that epalrestat increased the expression of tight junction proteins, and reduced the levels of cleaved-caspase3 and LC3 proteins in mouse BMVECs (bEnd.3 cells) exposed to oxygen-glucose deprivation (OGD). In addition, bicalutamide (an AKT inhibitor) and rapamycin (an mTOR inhibitor) increased the epalrestat-induced reduction in apoptosis and autophagy related protein levels in bEnd.3 cells with OGD treatment. Our findings suggest that epalrestat improves BBB function, which may be accomplished by reducing AR activation, promoting tight junction proteins expression, and upregulating AKT/mTOR signaling pathway to inhibit apoptosis and autophagy in BMVECs.

Role of ADAM33 short isoform as a tumor suppressor in the pathogenesis of thyroid cancer via oncogenic function disruption of full-length ADAM33.

Thyroid cancer is the most prevalent endocrine malignancy globally; however, its underlying pathogenesis remains unclarified. Reportedly, alternative splicing is involved in processes such as embryonic stem and precursor cell differentiation, cell lineage reprogramming, and epithelial-mesenchymal transitions. ADAM33-n, an alternative splicing isoform of ADAM33, encodes a small protein containing 138 amino acids of the N-terminal of full-length ADAM33, which constructs a chaperone-like domain that was previously reported to bind and block the proteolysis activity of ADAM33. In this study, we reported for the first time that ADAM33-n was downregulated in thyroid cancer. The results of cell counting kit-8 and colony formation assays showed that ectopic ADAM33-n in papillary thyroid cancer cell lines restricted cell proliferation and colony formation. Moreover, we demonstrated that ectopic ADAM33-n reversed the oncogenic function of full-length ADAM33 in cell growth and colony formation in the MDA-T32 and BCPAP cells. These findings indicate the tumor suppressor ability of ADAM33-n. Altogether, our study findings present a potential explanatory model of how the downregulation of the oncogenic gene ADAM33 promotes the pathogenesis of thyroid cancer.

Structural Basis of the Inhibition of L-Methionine γ-Lyase from Fusobacterium nucleatum.

Fusobacterium nucleatum is a lesion-associated obligate anaerobic pathogen of destructive periodontal disease; it is also implicated in the progression and severity of colorectal cancer. Four genes (FN0625, FN1055, FN1220, and FN1419) of F. nucleatum are involved in producing hydrogen sulfide (H2S), which plays an essential role against oxidative stress. The molecular functions of Fn1419 are known, but their mechanisms remain unclear. We determined the crystal structure of Fn1419 at 2.5 Å, showing the unique conformation of the PLP-binding site when compared with L-methionine γ-lyase (MGL) proteins. Inhibitor screening for Fn1419 with L-cysteine showed that two natural compounds, gallic acid and dihydromyricetin, selectively inhibit the H2S production of Fn1419. The chemicals of gallic acid, dihydromyricetin, and its analogs containing trihydroxybenzene, were potentially responsible for the enzyme-inhibiting activity on Fn1419. Molecular docking and mutational analyses suggested that Gly112, Pro159, Val337, and Arg373 are involved in gallic acid binding and positioned close to the substrate and pyridoxal-5'-phosphate-binding site. Gallic acid has little effect on the other H2S-producing enzymes (Fn1220 and Fn1055). Overall, we proposed a molecular mechanism underlying the action of Fn1419 from F. nucleatum and found a new lead compound for inhibitor development.

Gene Expression Network and Circ_0008012 Promote Progression in MLL/AF4 Positive Acute Lymphoblastic Leukemia.

BACKGROUND: Acute lymphoblastic leukemia with MLL/AF4 rearrangement remains a major hurdle to improving outcomes. Gene network and circRNAs have been found to participate in tumorigenesis, while their roles in leukemia still need to be explored. Recent patents have shown that circRNAs exhibit the markers for the children ALL, although the target and related mechanism remain to be elucidated. OBJECTIVE: This study aims to explore the possible targets and mechanisms of ALL with MLLAF4 rearrangement. METHODS: We first generated a gene network focusing on MLL-AF4 rearrangement. Cell viability was determined with Cell Counting Kit-8 assay. The cell apoptosis was tested by the Annexin V/PI assay. The RNA-protein complexes were analyzed by qRT-PCR, and the pathway proteins were analyzed by western blot. RESULTS: This gene network was associated with biological processes, such as nucleic acid metabolism and immunity, indicating its key role in inflammation. We found that circ_0008012 was upregulated in MLL/AF4 ALL cells and regulated cell proliferation and apoptosis. Further computed simulation and RIP showed that IKKß was the strongest protein in the NF-κB pathway binding with circ_0008012. As a result, possible regulation of circ_0008012 is suggested by binding IKKß in the IKKα:IKKß:IKKγ compound, which then phosphorylates IκB and activates NF- κB:p65:p300 compound in cell nucleus, thereby leading to leukemia. CONCLUSION: We identified a gene network for MLL/AF4 ALL. Moreover, circ_0008012 may be a therapeutic target for this subtype of ALL.

E2Fs co-participate in cadmium stress response through activation of MSHs during the cell cycle.

Cadmium is one of the most common heavy metal contaminants found in agricultural fields. MutSα, MutSß, and MutSγ are three different MutS-associated protein heterodimer complexes consisting of MSH2/MSH6, MSH2/MSH3, and MSH2/MSH7, respectively. These complexes have different mismatch recognition properties and abilities to support MMR. However, changes in mismatch repair genes (OsMSH2, OsMSH3, OsMSH6, and OsMSH7) of the MutS system in rice, one of the most important food crops, under cadmium stress and their association with E2Fs, the key transcription factors affecting cell cycles, are poorly evaluated. In this study, we systematically categorized six rice E2Fs and confirmed that OsMSHs were the downstream target genes of E2F using dual-luciferase reporter assays. In addition, we constructed four msh mutant rice varieties (msh2, msh3, msh6, and msh7) using the CRISPR-Cas9 technology, exposed these mutant rice seedlings to different concentrations of cadmium (0, 2, and 4 mg/L) and observed changes in their phenotype and transcriptomic profiles using RNA-Seq and qRT-PCR. We found that the difference in plant height before and after cadmium stress was more significant in mutant rice seedlings than in wild-type rice seedlings. Transcriptomic profiling and qRT-PCR quantification showed that cadmium stress specifically mobilized cell cycle-related genes ATR, CDKB2;1, MAD2, CycD5;2, CDKA;1, and OsRBR1. Furthermore, we expressed OsE2Fs in yeasts and found that heterologous E2F expression in yeast strains regulated cadmium tolerance by regulating MSHs expression. Further exploration of the underlying mechanisms revealed that cadmium stress may activate the CDKA/CYCD complex, which phosphorylates RBR proteins to release E2F, to regulate downstream MSHs expression and subsequent DNA damage repairment, thereby enhancing the response to cadmium stress.

Stem cell microencapsulation maintains stemness in inflammatory microenvironment.

Maintaining the stemness of the transplanted stem cell spheroids in an inflammatory microenvironment is challenging but important in regenerative medicine. Direct delivery of stem cells to repair periodontal defects may yield suboptimal effects due to the complexity of the periodontal inflammatory environment. Herein, stem cell spheroid is encapsulated by interfacial assembly of metal-phenolic network (MPN) nanofilm to form a stem cell microsphere capsule. Specifically, periodontal ligament stem cells (PDLSCs) spheroid was coated with FeIII/tannic acid coordination network to obtain spheroid@[FeIII-TA] microcapsules. The formed biodegradable MPN biointerface acted as a cytoprotective barrier and exhibited antioxidative, antibacterial and anti-inflammatory activities, effectively remodeling the inflammatory microenvironment and maintaining the stemness of PDLSCs. The stem cell microencapsulation proposed in this study can be applied to multiple stem cells with various functional metal ion/polyphenol coordination, providing a simple yet efficient delivery strategy for stem cell stemness maintenance in an inflammatory environment toward a better therapeutic outcome.