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Lipoxin A4 (LXA4) has been identified as the braking signal of inflammation, but the specific role of LXA4 in regulating the regenerative potential of periodontal ligament stem cells (PDLSCs) remains unclear. The aim of this study was to investigate whether and, if so, how LXA4 improves the osteogenic differentiation of PDLSCs in a lipopolysaccharide (LPS)‐induced inflammatory environment. We detected the effects of LXA4 on the osteogenic differentiation of PDLSCs in vitro and explored the bone regenerative potential of LXA4‐treated inflammatory PDLSCs in vivo using a calvarial critical sized defect model in male rats. RNA sequencing, real‐time PCR and western blot were performed to elucidate the relevant potential mechanisms. Results showed that LXA4 promoted the proliferation, migration and osteogenic differentiation of PDLSCs in vitro, and effectively improved the impaired osteogenic capacity of PDLSCs induced by LPS both in vitro and in vivo. Mechanistically, LXA4 significantly promoted the PI3K/AKT phosphorylation under inflammatory conditions. Additionally, LY294002 (a PI3K inhibitor) blocked the effect of LXA4, suggesting that the PI3K/AKT pathway is a key signaling pathway that mediates the effect of LXA4 on the osteogenesis of inflammatory PDLSCs. These findings indicate LXA4 may be a promising strategy for periodontal regeneration using inflammatory PDLSCs. [ABSTRACT FROM AUTHOR]

Genetic variation is considered to affect the N6‐methyladenosine (m6A) RNA transcript modification, which is the most prevalent posttranscriptional messenger RNA modification. This study aimed to identify m6A‐associated single‐nucleotide polymorphisms (m6A‐SNPs) that may affect m6A methylation from numerous periodontitis (PD) SNPs. We identified an abundance of m6A‐SNPs by analyzing raw data of published PD genome‐wide association studies and m6A‐SNPs list from the m6AVar database. Other evidence was found in public databases for expression quantitative trait loci (eQTL) and differential gene expression analysis. Accordingly, 1938 m6A‐SNPs were identified, 104 of which appeared to be associated with PD (p < .05) while 65 showed eQTL signals. Lastly, the leading SNP rs2723183 (p = 3.93E−07) was predicted to regulate local gene IL‐37 expression in PD (p = 2.64E−05; in GSE10334) and change regulatory motif RXRA. In summary, dozens of PD‐associated m6A‐SNPs were identified and their possible functions were demonstrated in this study. [ABSTRACT FROM AUTHOR]

DNA molecular machines show great promise in fields such as biomarker discovery and biological activity regulation, but operating DNA machines with specific functions within living systems remains extremely challenging. Although DNA machines have been engineered with exact molecular-level specifications, some intrinsic imperfections such as poor cell permeation and fragility in complex cytoplasmic milieu persist due to the well-established character of nucleic acid molecules. To circumvent these problems, we herein report a molecularly engineered, entropy-driven three-dimensional DNA amplifier (EDTD) that can operate inside living cells in response to a specific mRNA target. In particular, mRNA target/ EDTD interaction can specifically initiate an autonomous DNA circuit inside living cells owing to the exclusive entropy-driven force, thus providing enormous signal amplification for ultrasensitive detection of the mRNA. Moreover, owing to molecular engineering of a unique DNA tetrahedral framework into the DNA amplifier, EDTD exhibits significantly enhanced biostability and cellular uptake efficiency, which are prerequisites for DNA machines used for in vivo applications. This programmable DNA machine presents a simple and modular amplification mechanism for the detection of intracellular biomarkers. Moreover, this study provides a potentially valuable molecular tool for understanding the chemistry of cellular systems and offers a design blueprint for further expansion of DNA nanotechnology in living systems. [ABSTRACT FROM AUTHOR]

Oral infectious diseases may lead to bone loss, which makes it difficult to achieve satisfactory restoration. The rise of multidrug resistant bacteria has put forward severe challenges to the use of antibiotics. Silver (Ag) has long been known as a strong antibacterial agent. In clinic, gelatin sponge with colloid silver is used to reduce tooth extraction complication. To investigate how this material affect infected bone defects, methicillin-resistant Staphylococcus aureus (MRSA) infected 3-mm-diameter cranial defects were created in adult female Sprague-Dawley rats. One week after infection, the defects were debrided of all nonviable tissue and then implanted with gelatin sponge with colloid silver (gelatin/Ag group) or gelatin alone (gelatin group). At 2 and 3 days after debridement, significantly lower mRNA expression levels of IL-6 and TNF-α and lower plate colony count value were detected in gelatin/Ag group than control. Micro-CT analysis showed a significant increase of newly formed bone volume fraction (BV/TV) in gelatin/Ag treated defects. The HE stained cranium sections also showed a faster rate of defect closure in gelatin/Ag group than control. These findings demonstrated that gelatin sponge with colloid silver can effectively reduce the infection caused by MRSA in cranial defects and accelerate bone healing process. [ABSTRACT FROM AUTHOR]