Quantitative Real-Time Gene Profiling of Human Alveolar Osteoblasts

Unleashing the Potential of Nrf2: A Novel Therapeutic Target for Pulmonary Vascular Remodeling

Pulmonary vascular remodeling, characterized by the thickening of all three layers of the blood vessel wall, plays a central role in the pathogenesis of pulmonary hypertension (PH). Despite the approval of several drugs for PH treatment, their long-term therapeutic effect remains unsatisfactory, as they mainly focus on vasodilation rather than addressing vascular remodeling. Therefore, there is an urgent need for novel therapeutic targets in the treatment of PH. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a vital transcription factor that regulates endogenous antioxidant defense and emerges as a novel regulator of pulmonary vascular remodeling. Growing evidence has suggested an involvement of Nrf2 and its downstream transcriptional target in the process of pulmonary vascular remodeling. Pharmacologically targeting Nrf2 has demonstrated beneficial effects in various diseases, and several Nrf2 inducers are currently undergoing clinical trials. However, the exact potential and mechanism of Nrf2 as a therapeutic target in PH remain unknown. Thus, this review article aims to comprehensively explore the role and mechanism of Nrf2 in pulmonary vascular remodeling associated with PH. Additionally, we provide a summary of Nrf2 inducers that have shown therapeutic potential in addressing the underlying vascular remodeling processes in PH. Although Nrf2-related therapies hold great promise, further research is necessary before their clinical implementation can be fully realized.

Epigallocatechin gallate affects the proliferation of human alveolar osteoblasts and periodontal ligament cells, as well as promoting cell differentiation by regulating PI3K/Akt signaling pathway

Human periodontal ligament cells (hPDLCs) and human alveolar osteoblasts (hAOBs) play pivotal roles in periodontium. The regulatory effects of epigallocatechin gallate (EGCG) on hPDLCs and hAOBs remained unclear. This study probed into the functions of EGCG treating periodontal diseases. Cultured hAOBs and hPDLCs were passaged and observed by microscopic examination, and alkaline phosphatase (ALP) and immumohistochemical staining were performed for verification. hAOBs and hPDLCs were treated with EGCG and LY294002 + EGCG, then the proliferation of the two cells was assayed by MTT. Mineralization of the treated hAOBs and hPDLCs was detected by ALP activity experiment and Alizarin Red S staining kit. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting were performed for the detection of the expressions of differentiation-related mRNAs and PI3K/Akt signaling pathway-related proteins in the two cells. The third passage of hAOBs mainly showed triangle shape and were positive by ALP staining. hPDLCs in passage 3 adhered to the wall in spiral or radial pattern with positively stained vimentin and negatively stained keratin. Cell proliferation and ALP activity of the hAOBs and hPDLCs were increased by EGCG treatment. The mineralized nodules and expressions of differentiation-related mRNAs, the phosphorylation of PI3K and Akt of the hAOBs and hPDLCs were promoted by EGCG treatment, while the effects of LY294002 treatment were opposite to EGCG treatment. Epigallocatechin gallate affected the proliferation and differentiation of hAOBs and hPDLCs through regulating PI3K/Akt signaling pathway.

Notoginsenoside R1 promotes differentiation of human alveolar osteoblasts in inflammatory microenvironment through inhibiting NF‑κB pathway and activating Wnt/β‑catenin pathway

Alveolar bone is vital for dental implantation and periodontal treatment. Notoginsenoside R1 (NTR1) may promote the differentiation of human alveolar osteoblasts (HAOBs), but the underlying molecular mechanisms remain unclear. The present study investigated the pro-differentiation function of NTR1 on HAOBs in order to find new methods of dental treatment. HAOBs were surgically obtained from dental patients and the cells were isolated, cultured and identified under an inverted phase contrast microscope. The cells were treated with different concentrations of NTR1 alone or further stimulated by TNF-α. An alkaline phosphate (ALP) activity assay and alizarin red staining were performed to detect ALP activity and mineralization of the cells, respectively. Cell viability was assayed using an MTT assay. The expressions of osteogenic-related factors and the factors associated with the NF-κB and Wnt/β-catenin pathways were examined by reverse transcription-quantitative PCR or western blot analysis. Successfully passaged HAOBs presented blue granules and red calcium deposits after staining. The viability of HAOBs was unchanged following treatment with NTR1 at ≤20 µmol/l and/or TNF-α, but slightly reduced by 40 µmol/l NTR1. TNF-α-induced decreases of calcium nodules and ALP activity were decreased by NTR1 in HAOBs. TNF-α also regulated the expressions of runt-related transcription factor 2, osteopontin (OPN), osteocalcin (OCN), p50, phosphorylated p65, AXIN2, Dickkopf-related protein 1 and β-catenin, while the regulatory effect was reversed by NTR1. NTR1 promoted the differentiation of HAOBs in the TNF-α-induced inflammatory microenvironment through inhibiting the NF-κB pathway and activating the Wnt/β-catenin pathway.

Changing expression profiles of lncRNAs, circRNAs and mRNAs in esophageal squamous carcinoma

Abundant evidence indicates that long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs) serve important roles in tumorigenesis and tumour progression. However, their diagnostic and treatment value for esophageal squamous carcinoma (ESCC) remains unknown. A microarray (SBC human ceRNA array V1.0) was performed to assess the expression profiles and biological functions of lncRNAs, circRNAs and mRNAs in ESCC and para-cancerous tissues from three patients. Microarray data were validated by reverse transcription-quantitative polymerase chain reaction for a group of genes. A number of lncRNA-microRNAs (miRNA) and circRNA-miRNA-mRNA networks were constructed. Bioinformatics tools, including gene ontology and Kyoto Encyclopedia of Genes and Genomes biological pathway analyses, were used to predict the functions of differentially expressed lncRNAs, circRNAs and potentially co-expressed target genes. The results revealed that compared with the expression levels of para-cancerous tissues, 1,384 lncRNAs, 2,046 circRNAs and 936 mRNAs were frequently altered in ESCC tissues. Co-expression networks of lncRNAs-miRNAs-circRNAs-mRNAs were constructed based on the correlation analyses among the differentially expressed RNAs. Furthermore, using bioinformatics methods, correlation expression networks were constructed that included cis- and trans-regulatory elements. Therefore, these results suggest that lncRNAs and circRNAs may be involved in the pathogenesis and development of ESCC. These findings provide a novel and systematic perspective on the potential function of noncoding RNAs in ESCC.

Pathogenesis of medication-related osteonecrosis of the jaw: a comparative study of in vivo and in vitro trials

Objective This study was performed to determine whether the results of prevailing in vivo and in vitro studies offer a reliable model for investigation of medication-related osteonecrosis of the jaw (MRONJ). Methods Embase, Medline, and the Cochrane Library were searched for articles published from September 2003 to June 2017 involving experimental approaches to the pathogenesis of MRONJ. In vivo and in vitro trials were analyzed with respect to the scientific question, study design, methodology, and results. Results Of 139 studies, 87, 46, and 6 conducted in vivo, in vitro, and both in vivo and in vitro experiments, respectively. Rats, mice, dogs, minipigs, sheep, and rabbits were the preferred animal models used. Osteoblasts, osteoclasts, fibroblasts, keratinocytes, macrophages, and human umbilical vein endothelial cells were the preferred cell types. Zoledronate, alendronate, ibandronate, and risedronate were the most frequent bisphosphonates used. MRONJ was most reliably induced in minipigs because of the close relationship with human bone physiology. In vitro studies showed that reduced viability, growth, and migration of cells in the bone and soft tissues were causative for MRONJ. Other than exposed jawbone after tooth extraction, no reliable cofactors were found. Conclusion The minipig is the most suitable animal model for MRONJ.

Estrogen receptor‑β‑dependent effects of saikosaponin‑d on the suppression of oxidative stress‑induced rat hepatic stellate cell activation

Saikosaponin-d (SSd) is one of the major triterpenoid saponins derived from Bupleurum falcatum L., which has been reported to possess antifibrotic activity. At present, there is little information regarding the potential target of SSd in hepatic stellate cells (HSCs), which serve an important role in excessive extracellular matrix (ECM) deposition during the pathogenesis of hepatic fibrosis. Our recent study indicated that SSd may be considered a novel type of phytoestrogen with estrogen-like actions. Therefore, the present study aimed to investigate the effects of SSd on the proliferation and activation of HSCs, and the underlying mechanisms associated with estrogen receptors. In the present study, a rat HSC line (HSC-T6) was used and cultured with dimethyl sulfoxide, SSd, or estradiol (E₂; positive control), in the presence or absence of three estrogen receptor (ER) antagonists [ICI-182780, methylpiperidinopyrazole (MPP) or (R,R)-tetrahydrochrysene (THC)], for 24 h as pretreatment. Oxidative stress was induced by exposure to hydrogen peroxide for 4 h. Cell proliferation was assessed by MTT growth assay. Malondialdehyde (MDA), CuZn-superoxide dismutase (CuZn-SOD), tissue inhibitor of metalloproteinases-1 (TIMP- 1), matrix metalloproteinase-1 (MMP-1), transforming growth factor-β1 (TGF-β1), hydroxyproline (Hyp) and collagen-1 (COL1) levels in cell culture supernatants were determined by ELISA. Reactive oxygen species (ROS) was detected by flow cytometry. Total and phosphorylated mitogen-activated protein kinases (MAPKs) and α-smooth muscle actin (α-SMA) were examined by western blot analysis. TGF-β1 mRNA expression was determined by RT-quantitative (q)PCR. SSd and E₂ were able to significantly suppress oxidative stress-induced proliferation and activation of HSC-T6 cells. Furthermore, SSd and E₂ were able to reduce ECM deposition, as demonstrated by the decrease in transforming growth factor-β1, hydroxyproline, collagen-1 and tissue inhibitor of metalloproteinases-1, and by the increase in matrix metalloproteinase-1. These results suggested that the possible molecular mechanism could involve downregulation of the reactive oxygen species/mitogen-activated protein kinases signaling pathway. Finally, the effects of SSd and E₂ could be blocked by co-incubation with ICI-182780 or THC, but not MPP, thus indicating that ERβ may be the potential target of SSd in HSC-T6 cells. In conclusion, these findings suggested that SSd may suppress oxidative stress-induced activation of HSCs, which relied on modulation of ERβ.