Upregulated ATF1 Promotes Lipopolysaccharide Induced Inflammatory Response and Inhibits Osteogenic Differentiation of Human Periodontal Ligament Cells by Regulating NF-κB Pathway.

BACKGROUND: Periodontitis is a chronic inflammatory disease resulting from bacterial plaque infection. While the involvement of activating transcription factor 1 (ATF1) has been extensively explored in various human diseases, its specific role in periodontitis remains unclear. This study aims to elucidate the expression and biological function of ATF1 in the context of periodontitis. METHODS: Primary human periodontal ligament cells (hPDLCs) were procured from clinical samples and subsequently characterized. Following treatment with P. gingivalis lipopolysaccharide (LPS, 10 µg/mL), hPDLCs underwent transfection with either ATF1 vector or siRNA. The expression levels of ATF1 in LPS-treated hPDLCs or transfected cells were evaluated through real-time quantitative polymerase chain reaction (RT-qPCR) and western blot assay. Inflammatory factors, including interleukin-6 (IL-6), interleukin-8 (IL-8), tumor necrosis factor-alpha (TNF-α), and interleukin-1beta (IL-1ß), were quantified using Enzyme-linked Immunosorbent Assay (ELISA). The assessment of osteogenic proteins, such as runt-related transcription factor 2 (Runx2), osteopontin (OPN), and osteoprotegerin (OPG), as well as noncanonical nuclear factor-kappaB (NF-κB) pathway-related proteins (p65, p-p65, IkBα, p-IkBα), was conducted using western blot assay. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and flow cytometry assays were employed to detect cell viability. RESULTS: LPS induced an inflammatory response and hindered the osteogenic differentiation of hPDLCs (p < 0.05, p < 0.01). Furthermore, ATF1 silencing enhanced cell proliferation and suppressed apoptosis in LPS-stimulated hPDLCs (p < 0.05, p < 0.01). ATF1 silencing not only restrained the inflammatory response but also promoted the osteogenic differentiation of LPS-stimulated hPDLCs (p < 0.05, p < 0.01). Importantly, ATF1 silencing effectively blocked the LPS-induced activation of the NF-κB signaling pathway (p < 0.05, p < 0.01, p < 0.001). CONCLUSIONS: ATF1 emerges as a promising treatment option, inhibiting the osteogenic differentiation of hPDLCs and mitigating the inflammatory response by preventing the phosphorylation of the NF-κB signaling pathway.

Long-term efficacy and stability of miniscrew-assisted rapid palatal expansion in mid to late adolescents and adults: a systematic review and meta-analysis.

BACKGROUND: The purpose of this study is to investigate the long-term efficacy and stability of Miniscrew-assisted Rapid Palatal Expansion (MARPE), including its primary outcomes, namely the nasomaxillary complex transverse skeletal and dental expansion, and related secondary outcomes. METHODS: Electronic databases and manual literature searches, up to October 31, 2022, were performed. The eligibility criteria were the following: studies on patients with transverse maxillary deficiency treated with MARPE in adults and adolescents over 13.5 years of age. RESULTS: Ultimately, twelve articles were included in the analysis, one prospective and eleven retrospective observational studies. Five studies showed a moderate risk of bias, while the remaining seven studies were at a serious risk of bias. The GRADE quality of evidence was very low. MARPE is an effective treatment modality for transverse maxillary deficiency (mean success rate: 93.87%). Patients showed increased mean in the skeletal and dental transverse expansion. The basal bone composition, mean alveolar bone and mean dental expansion accounted for 48.85, 7.52, and 43.63% of the total expansion, respectively. There was a certain degree of skeletal and dental relapse over time. MARPE could also cause dental, alveolar, and periodontal side effects, and have an impact on other craniofacial bones, upper airway, and facial soft tissue. CONCLUSIONS: MARPE is an effective treatment for transverse maxillary deficiency, with a high success rate and a certain degree of skeletal and dental relapse over time.

CTGF Promotes the Osteoblast Differentiation of Human Periodontal Ligament Stem Cells by Positively Regulating BMP2/Smad Signal Transduction.

Objective: This work is aimed at revealing the role and the molecular mechanism of connective tissue growth factor 2 (CTGF) in the osteoblast differentiation of periodontal ligament stem cells (PDLSCs). Methods: The osteogenic differentiation of PDLSCs was induced by osteogenic induction medium (OM), and the expression level of osteogenic related proteins ALP, RUNX2, OCN, and CTGF was estimated using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting analysis. We constructed cell lines with CTGF overexpression or knockdown to verify the role of CTGF in the osteoblast differentiation of PDLSCs. Alkaline phosphatase (ALP) staining was introduced to measure the osteoblasts activity, and alizarin red S (ARS) staining was employed to test matrix mineralization. The interaction between CTGF and bone morphogenetic protein-2 (BMP-2) was determined by endogenous coimmunoprecipitation (Co-IP). Results: The expression level of CTGF was increased during the osteogenic induction of PDLSCs. Additionally, CTGF overexpression effectively maintained the stemness and facilitated the osteoblast differentiation in PDLSCs, and CTGF knockdown exerted opposite effects. Moreover, at molecular mechanism, CTGF increased the activity of BMP-2/Smad signaling pathway. Conclusion: This investigation verified that CTGF promotes the osteoblast differentiation in PDLSCs at least partly by activating BMP-2/Smad cascade signal.

[Effects of the traditional Chinese drug Dipsacus asperoides on the reconstruction of paradentium during the orthodontic tooth movement in rats].

PURPOSE: To observe the effects of the traditional Chinese drug Dipsacus asperoides on the construction of paradentium as well as the mechanism of action to osteoclast during the orthodontic tooth movement in rats. METHODS: Forty-eight female 8-week-old SPF Wistar rats were selected. They were randomly divided into 2 groups: Dipsacus asperoides group and control group. Then animal model for orthodontic tooth movement was established. 3 mL of NS was drenched to the control group and the Dipsacus asperoides group was given 6 g/kg per day Dipsacus asperoides decoction. The rats were executed in batch on the 7th, 14th, 21st, 28th day during the orthodontic treatment. The distances of the tooth movement were measured and slices from the periodontium of the maxillary first molar were observed under optical microscope. Measurement data were compared with t test and analysis of variance by PASW statistics18. RESULTS: The movement distance of the first molar was significantly larger in the Dipsacus asperoides group than that in the control group. The amount of osteoclast in Dipsacus asperoides group increased significantly compared with that in the control group (P<0.05). CONCLUSIONS: Dipsacus asperoides decoction is useful for the proliferation and differentiation of the osteoclast in orthodontic tooth movement. Supported by Shandong Provincial Science and Technology Development Project (Grant No.2008GG2NS02013) and Natural Science Foundation of Shandong Province (Grant No.Q2008C12).