Osteopontin Protein Expression Research Articles

The role of osteopontin and osteocyte-derived factors in secondary hyperparathyroidism-induced myopathy.

Muscle weakness is a common symptom in CKD patients, and the pathway by which secondary hyperparathyroidism (SHPT) affects muscle function is unknown. Osteopontin (OPN), a bone matrix protein stimulated by PTH and phosphate, has been associated with inflammatory muscle diseases. In this observational and prospective cohort study, we evaluated 30 patients with severe SHPT (39 ± 12yr; 18 women), before and 6mo after parathyroidectomy (PTx). We examined the relationships among CKD-mineral and bone disorder parameters; myokine and inflammatory cytokine levels; and changes in resting energy expenditure (REE), muscle function, BMD, and muscle-related proteins. At baseline, the patients showed low gene expression of muscle turnover markers and irisin, as well as high protein expression of OPN, transforming growth factor beta (TGF-β), and fibroblast growth factor 21. Six months after PTx, REE and muscle mass had not changed, but physical performance, muscle strength, and bone mass improved, more so in patients undergoing total PTx. Also, there were reductions in the protein expression of OPN (11 vs 3%, p=.01) and TGF-β (21 vs 7%, p=.002) in muscle, together with a significant increase in irisin muscular levels (30 vs 35pg/mg, p=.02). The gain in bone mass and the increase in irisin levels correlated with a reduction in PTH. The levels of interleukin (IL)-1β, tumor necrosis factor alpha, and IL-17 (markers of myositis) were also lower after PTx. Our data suggest that SHPT plays a role in CKD-induced muscle dysfunction, indirectly, via release of bone-specific proteins, which is partially reverted with PTx.

Osteopontin expression in dromedary camel's conceptuses during the peri-implantation period.

The reproductive efficiency of dromedary camels is hindered by challenges such as early embryonic mortality, which may be attributed to a lack of synchronization between conceptus signalling and uterine receptivity. Understanding the intricate biological processes involved in feto-maternal interactions during implantation is crucial to address these limitations. Osteopontin (OPN) is a protein involved in cell signalling and adhesion, playing a crucial role in embryonic implantation. Previous studies have shown the presence of OPN in the uterine endometrium of various mammalian species including dromedary camels. However, the expression pattern of OPN in dromedary conceptuses remains unexplored. Thus, the current study aimed, for the first time, to investigate the temporospatial expression of OPN in dromedary conceptuses during the peri-implantation period at Days 8, 10, and 12 of pregnancy. Twelve conceptuses were recovered non-surgically from pregnant females on Days 8, 10, 12 of pregnancy. Quantitative real-time PCR (qrt-PCR), immunohistochemistry (IHC), and immunofluorescence (IF) were employed for analysis of the expression of OPN mRNA and protein. The results revealed significant increases in both OPN mRNA and protein expression started on Day 10 and peaked at Day 12 of pregnancy. Immuno-localization confirmed the presence of OPN protein in the trophectoderm and endoderm of dromedary conceptuses. In conclusion, the expression and localization of OPN during the peri-implantation period in dromedary conceptuses imply its involvement as a crucial reproductive factor and its upregulation during this period, with a pronounced increase close to attachment time (Day 12 of pregnancy) further supports its role in embryo adhesion, implantation, and placentation.

P-401 Aging affects endometrial receptivity factors. Can DHEA modulate this age-related effect?

Abstract Study question Identification of age-related gene expression differences of the human endometrium during its receptive period – Dehydroepiandrosterone (DHEA) effects. Summary answer Decrease in expression of OPN and HOXA10, receptivity markers, between increasing female age groups in primary human endometrial cells was presented. DHEA altered gene expression. What is known already The increased infertility noted in the world population, has been related to increasing maternal age. Our previous work points out the role of women’s age in endometrial cell function. Endometrial proliferation and differentiation are two important steps that lead to increased cell receptivity during the window of implantation. Optimal receptivity is achieved also through changes inexpression of several factors throughout the endometrial cycle. It is well known that androgen levels, in the female reproductive system, decrease with increasing age.Therefore, DHEA an androgen precursor, found to be reduced with age is thought to be a candidate for infertility treatment. Study design, size, duration Maternal age has not been previously directly correlated with endometrial receptivity factors. We studied 39 endometrial samples divided in three different women’s age groups (25-35 years, 36-40 years and 41-46years) and changes in the mRNA and protein expression of osteopontin (OPN), CD44 and HOXA10 in human endometrium stromal cells were analyzed, in vitro. DHEA was added on stromal cells (decidualized or not) in order to observe changes in mRNA expression. Participants/materials, setting, methods Pipelle endometrial biopsies (secretory phase) were collected from ovulating, fertile, Caucasian women volunteers aged 25–46 years. Stromal cells were isolated. These samples were divided into three age groups: 25-35 years, 36-40 years and 41-46 years. Protein and mRNA expression of receptivity modulators OPN, CD44 and HOXA10 were analyzed using Real-time PCR and Western blot analysis, respectively. Stromal cells were decidualized in vitrousing bromo-8-cAMP in order to observe DHEA effects. Main results and the role of chance Data presented showed a statistically significant decrease (p ≤ 0.05) in OPN expression levels with increasing age groups. Women included in age group of 41-45y presented a significant downregulation of OPN expression compared to younger age group 25-35y (p ≤ 0.01).CD44 expressiondid not differ with age. Furthermore, a statistically significant decrease (p ≤ 0.05) was evident in HOXA10 expression levels with increasing age. Women belonging to the age group 41-45y expression presented with significant HOXA10 downregulation compared to younger age group 25-35y (p ≤ 0.05). Analysis of OPN protein levels showed that cell-extracted OPN decreased from theage of 33y, while the secreted protein gradually decreased from the age of 38y. CD44 protein expression, similarly to the mRNA expression did not show differences with age. HOXA10 protein expression was found to be decreased mainly after the age of41y. DHEA changed, with statistical significance, the expression of decidualization marker IGFBP and OPN in decidualized stromal cells. Overall, our results support our hypothesis as expected, but we must also consider specific cases where older women have the same results as younger ones and the opposite, so factors that are specific for each individual must be further investigated. Limitations, reasons for caution It must be pointed out that there is a plethora of characterized molecules like cytokines and immune cells that also participate in the optimal receptivity status of the endometrium – leading to a successful implantation procedure – that future studies need to examine, as well, in relation to women’s age. Wider implications of the findings Human endometrial aging can affect embryo receptivity markers and therefore, receptivity. Further investigation of receptivity factors that change with the age could be a useful pool in identifying targets for diagnosis and therapy of human implantation failure. Also, DHEA must be further investigated as a tool for infertility therapy. Trial registration number not applicable

Pharmacological effects of methysticin and L-sulforaphane through the Nrf2/ARE signaling pathway in MLO-Y4 osteocytes: in vitro study

BackgroundOxidative stress plays a crucial role in the pathogenesis of many skeletal diseases by inducing osteocyte death. The transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) is a master regulator of various antioxidant gene expressions through antioxidant response element (ARE) against cellular oxidative stress and can be induced by various stimulants, including the phytochemicals methysticin (MET) and L-sulforaphane (SFN). This study aimed to establish an osteocyte in vitro model to investigate the pharmacological effects of MET and SFN on the Nrf2/ARE pathway. MethodsMLO-Y4 murine osteocytes and the stably transduced MLO-Y4-SIN-lenti-ARE reporter gene cell line were used. MET and SFN were used as Nrf2 inducers. The cytotoxicity of MET, SFN, and hydrogen peroxide (H2O2) was evaluated using the CytoTox-Glo™ Assay. Time- and dose-dependent ARE induction was examined by Monoluciferase Assay. The mRNA and protein expressions of Nrf2 target markers, such as heme-oxygenase 1 (Ho-1), NADPH quinone dehydrogenase 1 (Nqo1), and thioredoxin reductase 1 (Txnrd1), were detected by RT-qPCR, Western Blot, and immunofluorescence staining, respectively. Osteogenesis markers, osteopontin, and osteocalcin were compared with and without treatment by immunofluorescence staining. ResultsThe experimental data showed that MET and SFN induced ARE activity in a time- and dose-dependent manner and increased the mRNA and protein expression of antioxidant markers compared to vehicle-treated controls. The protein expression of osteopontin and osteocalcin in the samples treated with SFN were significantly higher than without treatment, and the number of cell death treated with SFN was significantly lower than without treatment under H2O2-induced stress conditions. ConclusionsNrf2 inducers MET and SFN increased the mRNA expression of antioxidant genes through the Nrf2/ARE pathway in osteocytes. Notably, SFN increased the protein expression of osteocyte-associated osteogenic markers and suppressed cell death under H2O2-induced stress condition. Thus, Nrf2 stimulators can exert stress-relieving and osteogenic effects on osteocytes.

Oleanolic acid exerts bone anabolic effects via activation of osteoblastic 25-hydroxyvitamin D 1-alpha hydroxylase

Oleanolic acid (OA) is previously shown to exert bone protective effects in aged animals. However, its role in regulating osteoblastic vitamin D bioactivation, which is one of major causes of age-related bone loss, remains unclear. Our results revealed that treatment of OA significantly increased skeletal CYP27B1 expression and circulating 1,25(OH)2D3 in ovariectomized mice (p <0.01). Moreover, OA upregulated CYP27B1 protein expression and activity, as well as the vitamin D-responsive bone markers alkaline phosphatase (ALP) activity and osteopontin (OPN) protein expression, in human osteoblast-like MG-63 cells (p<0.05). CYP27B1 expression increased along with the osteoblastic differentiation of human bone marrow derived mesenchymal stem cells (hMSCs). CYP27B1 expression and cellular 1,25(OH)2D3 production were further potentiated by OA in cells at mature osteogenic stages. Notably, our study suggested that the osteogenic actions of OA were CYP27B1 dependent. In summary, the bone protective effects of OA were associated with the induction of CYP27B1 activity and expression in bone tissues and osteoblastic lineages. Hence, OA might be a potential approach for management of age-related bone loss.

Impact of hyperoxia on the phenotype of pulmonary artery smooth muscle cells

Objective: To investigate the influence of varied oxygen (O2) concentration environments on the phenotypic transformation of pulmonary artery smooth muscle cells (PASMC) and the mechanism of pulmonary hypertension. Methods: Primary rat PASMC were isolated and cultured through the process of enzymatic digestion. Following identification, the stable passaged PASMC were subjected to a 6-hour incubation in sealed containers with normal O2 content (group C) and relative O2 content comprising 55% (group H55), 75% (group H75), and 95% (group H95). mRNA and protein expression of α-Actin (α-SMA), smooth muscle 22α (SM22α), osteopontin (OPN), and matrix metalloproteinase-2 (MMP-2) were measured using real-time quantitative PCR and western blot analysis. Results: The H55 group displayed no significant difference from the C group in terms of mRNA and relative protein expression levels for α-SMA, SM22α, OPN, and MMP-2 (all P>0.05). On the other hand, groups H75 and H95 exhibited a reduction in mRNA and relative protein expression of α-SMA and SM22α, along with an increase in mRNA and relative protein expression of OPN and MMP-2 when compared with both the C and H55 groups (all P<0.05). The H95 group showed a higher relative mRNA expression of MMP-2 as compared to the H75 group (P<0.05). Conclusions: Oxygen concentration environments of 75% or higher can serve as the foundation for the pathogenesis of pulmonary hypertension, essentially by inducing a phenotypic transformation in PASMC towards adopting a robust secretory function. This induction is contingent upon the concentration of oxygen present.

Effect of recombinant human bone morphogenetic protein-2 and osteoprotegerin-Fc in MC3T3-E1 cells.

We compared the osteoblastogenesis by serially administrating recombinant human bone morphogenetic protein-2 (rhBMP-2) and osteoprotegerin-immunoglobulin Fc segment complex (OPG-Fc). The MC3T3-E1 preosteoblast cell line was differentiated for 1, 3, and 7 days with a treatment of OPG-Fc in 10~200 ng/mL concentration and the cell viability was evaluated by Cell Counting Kit-8 analysis. The level of differentiation from MC3T3-E1 cells to osteoblasts was determined by alkaline phosphatase activity. The level of runt domain-containing transcription factor 2 (Runx2) and osteopontin (OPN) manifestation, involved in osteoblast differentiation, was examined by real-time polymerase chain reaction and western blotting. During MC3T3-E1 cell differentiation, the differentiation level was high with 1-day treatment using 100 ng/mL OPG-Fc. The treatment with 50 ng/mL rhBMP-2 for 7 days, followed by 1-day treatment with 100 ng/mL OPG-Fc produced the highest differentiation level, which was approximately 5.3 times that of the control group (p<0.05). The expression of Runx2 mRNA significantly increased, reaching 2.5 times the level of the control group under the condition of 7-day treatment with rhBMP-2 and 1-day treatment with OPG-Fc (p<0.001). The expression of Runx2 protein significantly increased to approximately 5.7 times that of the control group under the condition of 7-day treatment with rhBMP-2, followed by 1-day treatment with OPG-Fc (p<0.01). The expression of OPN protein showed no change from that of the control group under various conditions of rhBMP-2 and OPG-Fc combinations. These results imply that the treating preosteoblasts with rhBMP-2 first and then with OPG-Fc increased osteoblast differentiation efficacy.

Effect of a 630 nm light on vasculogenic mimicry in A549 lung adenocarcinoma cells in vitro

ObjectiveThe objective of this study was to investigate the effect of photodynamic therapy (PDT) on the formation of vasculogenic mimicry (VM) in the human lung adenocarcinoma A549 cell line in vitro. MethodsThe participants were divided into a blank control group, a photosensitizer group, a light group, and a PDT group. Cells from each group were cultured in three dimensions using Matrigel, and vasculogenic mimicry generation was observed microscopically. Periodic Acid-Schiff (PAS) staining was used to verify the vasculogenic mimicry structure. Reverse Transcription-Polymerase Chain Reaction (RT-PCR) was used to detect the expression levels of cellular osteopontin (OPN) and vascular endothelial growth factor (VEGF) mRNA. Western blotting was used to detect the expression levels of cellular OPN and VEGF protein. ResultsA549 cells cultured on Matrigel for about six hours revealed VM on PAS staining, and the number of formations was significantly reduced in the PDT group compared with other groups (P < 0.05). The RT-PCR results showed that the PDT group downregulated OPN and VEGF mRNA expression compared with each control group (P < 0.05). Western blot results showed that OPN and VEGF protein expression was downregulated in the PDT group compared with each control group (P < 0.05). The results of RT-PCR showed that the expression of OPN and VEGF mRNA was downregulated in the PDT group compared with each control group (P < 0.05). The results of Western blotting showed that the expression of OPN and VEGF was downregulated in the protein PDT group compared with each control group (P < 0.001). ConclusionPhotodynamic therapy significantly inhibited the formation of vasculogenic mimicry in human lung adenocarcinoma A549 cells in vitro and downregulated the expression of OPN, VEGF mRNA, and protein levels.

Osteopontin promotes gastric cancer progression via phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway.

Gastric cancer (GC) is one of the most common malignant tumors. Osteopontin (OPN) is thought to be closely related to the occurrence, metastasis and prognosis of many types of tumors. To investigate the effects of OPN on the proliferation, invasion and migration of GC cells and its possible mechanism. The mRNA and protein expression of OPN in the GC cells were analyzed by real-time quantitative-reverse transcription polymerase chain reaction and western blotting, and observe the effect of varying degree expression OPN on the proliferation and other behaviors of GC. Next, the effects of OPN knockdown on GC cells migration and invasion were examined. The short hairpin RNA (shRNA) and negative control shRNA targeting OPN-shRNA were transfected into the cells according to the manufacturer's instructions. Non transfected cells were classified as control in the identical transfecting process. 24 h after RNA transfection cell proliferation activity was detected by 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide assay, and cell invasiveness and migration were detected by Trans well assay. Meanwhile, the expression of protein kinase B (AKT), matrix metalloproteinase 2 (MMP-2) and vascular endothelial growth factor (VEGF) in the human GC cell lines was detected by reverse transcription polymerase chain reaction and western blotting. The results of this study revealed that OPN mRNA and protein expression levels were highly expressed in SGC-7901 cells. OPN knockdown by specific shRNA noticeably reduced the capabilities of proliferation, invasion and migration of SGC-7901 cells. Moreover, in the experiments of investigating the underlying mechanism, results showed that OPN knockdown could down-regulated the expression of MMP-2 and VEGF, it also decreased the phosphorylation of AKT. Meanwhile, the protein expression levels of MMP-2, VEGF and phosphorylated AKT was noticeable lower than that in control group in the GC cells after they were added to phosphatidylinositol-3-kinase (PI3K) inhibitor (LY294002). These results suggested that OPN though PI3K/AKT/mammalian target of rapamycin signal pathway to up-regulate MMP-2 and VEGF expression, which contribute SGC-7901 cells to proliferation, invasion and migration. Thus, our results demonstrate that OPN may serve as a novel prognostic biomarkers as well as a potential therapeutic targets for GC.

Hesperetin attenuates the expression of markers of adipose tissue fibrosis in pre-adipocytes

BackgroundExcessive extracellular matrix (ECM) deposition in adipose tissue is a hallmark of fibrosis, leading to disrupted adipose tissue homeostasis and metabolic dysfunction. Hesperetin, a flavonoid compound, has shown promising anti-inflammatory, anti-obesity and anti-diabetic properties. Therefore, we investigated the anti-fibrotic effects of hesperetin, through targeting ECM components and matrix metalloproteinase enzymes.Methods3T3-L1 cells were cultured in DMEM, containing 10% FBS and 1% penicillin/streptomycin. Cells were treated with a range of hesperetin concentrations, and the cell viability was determined using MTT assay. Subsequently, the expression of genes encoding collagen VI, osteopontin, matrix metalloproteinase-2 (Mmp-2) and Mmp-9 was analyzed using specific primers and real-time PCR technique. To evaluate protein levels of collagen VI and osteopontin, Western blotting was performed.ResultsHesperetin affected the viability of 3T3-L1 adipocytes with IC50 of 447.4 µM, 339.2 µM and 258.8 µM (24 h, 48 and 72 h, respectively). Hesperetin significantly reduced the gene and protein expression of both collagen VI and osteopontin in 3T3-L1 pre-adipocytes, in a time- and dose-dependent manner. Hesperetin was also able to cause a remarkable decline in gene expression of Mmp2 and Mmp9.ConclusionHesperetin could potently reduce the production of markers of adipose tissue fibrosis and might be considered a potential anti-fibrotic compound in obesity. Thus, hesperetin has the potency to be used for the treatment of obesity-associated fibrosis.

Effect of the secretome of mesenchymal stem cells overexpressing BMP-9 on osteoblast differentiation and bone repair.

The secretome present in the conditioned medium (CM) of mesenchymal stem cells (MSCs) is a promising tool to be used in therapies to promote bone regeneration. Considering the high osteogenic potential of the bone morphogenetic protein 9 (BMP-9), we hypothesized that the secretome of MSCs overexpressing BMP-9 (MSCsBMP-9 ) enhances the osteoblast differentiation of MSCs and the bone formation in calvarial defects. CM of either MSCsBMP-9 (CM-MSCsBMP-9 ) or MSCs without BMP-9 overexpression (CM-MSCsVPR ) were obtained at different periods. As the CM-MSCsBMP-9 generated after 1 h presented the highest BMP-9 concentration, CM-MSCsBMP-9 and CM-MSCsVPR were collected at this time point and used to culture MSCs and to be injected into mouse calvarial defects. The CM-MSCsBMP-9 enhanced the osteoblast differentiation of MSC by upregulating RUNX2, alkaline phosphatase (ALP) and osteopontin protein expression, and ALP activity, compared with CM-MSCsVPR . The CM-MSCsBMP-9 also enhanced the bone repair of mouse calvarial defects, increasing bone volume, bone volume/total volume, bone surface, and trabecular number compared with untreated defects and defects treated with CM-MSCsVPR or even with MSCsBMP-9 themselves. In conclusion, the potential of the MSCBMP-9 -secretome to induce osteoblast differentiation and bone formation shed lights on novel cell-free-based therapies to promote bone regeneration of challenging defects.

Incorporation of synthetic water-soluble curcumin polymeric drug within calcium phosphate cements for bone defect repairing.

Modified macroporous structures and active osteogenic substances are necessary to overcome the limited bone regeneration capacity and low degradability of self-curing calcium phosphate cement (CPC). Curcumin (CUR), which possesses strong osteogenic activity and poor aqueous solubility/bioavailability, esterifies the side chains in hyaluronic acid (HA) to form a water-soluble CUR-HA macromolecule. In this study, we incorporated the CUR-HA and glucose microparticles (GMPs) into the CPC powder to fabricate the CUR-HA/GMP/CPC composite, which not only retained the good injectability and mechanical strength of bone cements, but also significantly increased the cement porosity and sustained release property of CUR-HA in vitro. CUR-HA incorporation greatly improved the differentiation ability of bone marrow mesenchymal stem cells (BMSCs) to osteoblasts by activating the RUNX family transcription factor 2/fibroblast growth factor 18 (RUNX2/FGF18) signaling pathway, increasing the expression of osteocalcin and enhancing the alkaline phosphatase activity. In addition, in vivo implantation of CUR-HA/GMP/CPC into femoral condyle defects dramatically accelerated the degradation rate of cement and boosted local vascularization and osteopontin protein expression, and consequently promoted rapid bone regeneration. Therefore, macroporous CPC based composite cement with CUR-HA shows a remarkable ability to repair bone defects and is a promising translational application of modified CPC in clinical practice.

Alterations in the balance of sex hormones may affect rat prostatic inflammation and fibrosis, and osteopontin might be involved in this process.

This study aimed to investigate the effects of sex hormone imbalance on rat prostatic inflammation and fibrosis and identify the key molecules involved. Castrated Sprague-Dawley (SD) rats were treated with a constant dose of oestradiol (E2) and different doses of dihydrotestosterone (DHT) to achieve different oestrogen/androgen ratios. After 8weeks, serum E2 and DHT concentrations, relative seminal vesicle weights, histopathological changes and inflammation were measured, collagen fiber content and oestrogen receptor (ER) and androgen receptor (AR) expression were detected, mRNA sequencing and bioinformatics analysis were performed to identify differentially expressed genes (DEGs). The severity of inflammation in the rat dorsolateral prostate (DLP) was higher, collagen fibre content and ER expression in the rat DLP and prostatic urethra were increased and AR expression in the rat DLP was decreased in the 1:1 E2/DHT-treated group than that in the 1:10 E2/DHT-treated group. RNA-seq analysis identified 487 DEGs, and striking increases in the expression of mRNAs encoding collagen, collagen synthesis and degradation enzymes, growth factors and binding proteins, cytokines and chemokines, and cell-surface molecules were confirmed in the 1:1 E2/DHT-treated group compared to the 1:10 E2/DHT-treated group. mRNA expression of secreted phosphoprotein 1 (Spp1) and protein expression of osteopontin (OPN, encoded by Spp1) were increased in the 1:1 E2/DHT-treated group compared to the 1:10 E2/DHT-treated group, and Spp1 expression correlated positively with Mmp7, Cxcl6 and Igfn1 expression. The imbalance in the oestrogen/androgen ratio may affect rat prostatic inflammation and fibrosis, and OPN might be involved in this process.

Sequential Release of Panax Notoginseng Saponins and Osteopractic Total Flavone from Poly (L-Lactic Acid) Scaffold for Treating Glucocorticoid-Associated Osteonecrosis of Femoral Head.

Glucocorticoids inhibit angiogenesis in the femoral head, which fails to nourish the bone tissue and leads to osteonecrosis. Restoring angiogenesis is not only essential for vessel formation, but also crucial for osteogenesis. Poly (L-lactic acid) (PLLA) is commonly used in the bone tissue engineering field. Panax notoginseng saponins (PNS) and osteopractic total flavone (OTF) promote angiogenesis and osteogenesis, respectively. We designed a sequentially releasing PLLA scaffold including PLLA loaded with OTF (inner layer) and PLLA loaded with PNS (outer layer). We assessed the osteogenic effect of angiogenesis in this scaffold by comparing it with the one-layered scaffold (PLLA embedded with OTF and PNS) in vivo. Results from the micro-CT showed that the data of bone mineral density (BMD), bone volume (BV), and percent bone volume (BV/TV) in the PO-PP group were significantly higher than those in the POP group (p &lt; 0.01). Histological analyses show that the PO-PP scaffold exhibits better angiogenic and osteogenic effects compared with the one-layered scaffold. These might result from the different structures between them, where the sequential release of a bi-layer scaffold achieves the osteogenic effect of vascularization by initially releasing PNS in the outer layer. We further explored the possible mechanism by an immunohistochemistry analysis and an immunofluorescence assay. The results showed that the protein expressions of vascular endothelial growth factor (VEGF) and platelet endothelial cell adhesion molecule-1(CD31) in the PO-PP scaffold were significantly higher than those in the POP scaffold (p &lt; 0.01); the protein expressions of osteocalcin (OCN), osteopontin (OPN), and alkaline phosphatase (ALP) in the PO-PP scaffold were significantly higher than those in the POP scaffold (p &lt; 0.05). Upregulating the expressions of angiogenic and osteogenic proteins might be the possible mechanism.

Effects of customized CAD/CAM abutments on cytokine levels in peri-implant crevicular fluid during early implant healing: a pilot study

ObjectivesThis study aimed to assess levels of biomarkers associated with inflammation and tissue destruction in peri-implant crevicular fluid (PICF) of implants provided with customized or standard healing abutments during early implant healing.Materials and methodsThirty implants were placed in 22 patients with partial posterior edentulism. Subsequently, test group implants (n=15) received one-piece titanium abutments that were fabricated using computer-aided design/computer-aided manufacturing (CAD/CAM). Control group implants (n=15) were provided with standard abutments. PICF collection and standardized periapical radiographs were carried out at suture removal one week later, following crown delivery after 3 months and at 6 months. Expression of C-reactive protein (CRP), interferon-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12A, IL-17A, macrophage inflammatory protein (MIP)-1α, matrix metalloproteinase (MMP)-13, osteopontin, osteoactivin, Receptor Activator of NF-κB (RANK), and TGF-β were analyzed using a multiplex ELISA kit.ResultsBoth groups showed a significant decrease in protein expression of CRP, IL-1β, IL-6, IL-8, MIP-1α, osteopontin, osteoactivin, and TGF-β, while MMP-13 levels increased during the observation period. A rise in OPG and RANK levels was detected among customized abutments. Expression of CRP was higher, whereas IL-1β, IL-1α, and MIP-1α were decreased in control compared to test group implants after 6 months. Marginal bone loss did not depend on abutment modality.ConclusionsBoth abutment types showed distinctive temporal expression of inflammatory biomarkers during 6 months following implant placement.Trial registrationISRCTN98477184, registration date 18/05/2022Clinical relevanceCustomized healing abutments exert similar effects on inflammation during early implant healing compared to standard healing abutments.

The Protective Effects on Ischemia-Reperfusion Injury Mechanisms of the Thoracic Aorta in Daurian Ground Squirrels (Spermophilus dauricus) over the Torpor-Arousal Cycle of Hibernation.

Hibernators are a natural model of vascular ischemia–reperfusion injury; however, the protective mechanisms involved in dealing with such an injury over the torpor–arousal cycle are unclear. The present study aimed to clarify the changes in the thoracic aorta and serum in summer-active (SA), late-torpor (LT) and interbout-arousal (IBA) Daurian ground squirrels (Spermophilus dauricus). The results show that total antioxidant capacity (TAC) was unchanged, but malondialdehyde (MDA), hydrogen peroxide (H2O2), interleukin-1β (IL-1β) and tumor necrosis factor α (TNFα) were significantly increased for the LT group, whereas the levels of superoxide dismutase (SOD) and interleukin-10 (IL-10) were significantly reduced in the LT group as compared with the SA group. Moreover, the levels of MDA and IL-1β were significantly reduced, whereas SOD and IL-10 were significantly increased in the IBA group as compared with the SA group. In addition, the lumen area of the thoracic aorta and the expression of the smooth muscle cells (SMCs) contractile marker protein 22α (SM22α) were significantly reduced, whereas the protein expression of the synthetic marker proteins osteopontin (OPN), vimentin (VIM) and proliferating cell nuclear antigen (PCNA) were significantly increased in the LT group as compared with the SA group. Furthermore, the smooth muscle layer of the thoracic aorta was significantly thickened, and PCNA protein expression was significantly reduced in the IBA group as compared with the SA group. The contractile marker proteins SM22α and synthetic marker protein VIM underwent significant localization changes in both LT and IBA groups, with localization of the contractile marker protein α-smooth muscle actin (αSMA) changing only in the IBA group as compared with the SA group. In tunica intima, the serum levels of heparin sulfate (HS) and syndecan-1 (Sy-1) in the LT group were significantly reduced, but the serum level of HS in the IBA group increased significantly as compared with the SA group. Protein expression and localization of endothelial nitric oxide synthase (eNOS) was unchanged in the three groups. In summary, the decrease in reactive oxygen species (ROS) and pro-inflammatory factors and increase in SOD and anti-inflammatory factors during the IBA period induced controlled phenotypic switching of thoracic aortic SMCs and restoration of endothelial permeability to resist ischemic and hypoxic injury during torpor of Daurian ground squirrels.

Moxifloxacin induces aortic aneurysm and dissection by increasing osteopontin in mice

Fluoroquinolones are one of the most frequently prescribed antibiotics. However, their use increases the risk of Aortic aneurysm and dissection (AAD). The mechanism underlying this effect remains unclear. AAD are caused by weakening of the aortic wall and loss of vascular smooth muscle cells. Osteopontin is involved in the occurrence and development of AAD. The aim of the present study was to examine the role of moxifloxacin, a fluoroquinolone, in the occurrence of AAD using a moderate-severity AAD mouse model.Four-week-old male C57BL/6J mice were fed a high-fat diet. At 8 weeks of age, the mice were infused with saline or angiotensin II (1000 ng kg−1 min−1) via osmotic minipumps for 4 weeks, and then orally administered water (vehicle) or moxifloxacin (30 and 100 mg kg−1 day−1) for another 3 weeks. Moxifloxacin (30 and 100 mg kg−1 day−1) induced AAD and elastin degradation in aortic tissues, as revealed by hematoxylin and eosin staining and elastica-van Gieson staining. Additionally, immunohistochemical staining and Western blot analyses showed that moxifloxacin 100 mg kg−1 day−1 decreased the protein expression of smooth muscle protein 22α, one of the markers of the contractile phenotype of vascular smooth muscle cells, in aortic tissues compared to vehicle and moxifloxacin 30 mg kg−1 day−1. Furthermore, moxifloxacin (100 mg kg−1 day−1) increased the protein expression of osteopontin and matrix metalloproteinases-2 in the aortic tissues when compared to control.Moxifloxacin may induce the onset of AAD and weakening of the aortic media by increasing the expression of osteopontin and matrix metalloproteinase-2 and decreasing that of smooth muscle protein 22α in aortic tissue.

Anti-Osteoporosis Effects of the Fruit of Sea Buckthorn (Hippophae rhamnoides) through Promotion of Osteogenic Differentiation in Ovariectomized Mice.

The fruit of Hippophae rhamnoides has been widely used for medicinal purposes because of its anti-inflammatory, antioxidant, antiplatelet, and antimicrobial effects. Since there are no clear reports on the therapeutic efficacy of H. rhamnoides in osteoporosis, this study aimed to confirm the potential use of H. rhamnoides for the treatment of osteoporosis through its osteogenic differentiation-promoting effect in ovariectomized mice. Through an in vitro study, we compared the effects of the EtOH extract of H. rhamnoides fruits (EHRF) on the differentiation of C3H10T1/2, a mouse mesenchymal stem cell line, into osteoblasts based on alkaline phosphatase (ALP) staining and the relative expression of osteogenesis-related mRNAs. The EHRF significantly stimulated the differentiation of mesenchymal stem cells into osteoblasts and showed 7.5 times (* p < 0.05) higher osteogenesis than in the untreated control. A solvent fractionation process of EHRF showed that the hexane-soluble fraction (HRH) showed 10.4 times (** p < 0.01) higher osteogenesis than in the untreated control. Among the subfractions derived from the active HRH by preparative HPLC fractionation, HRHF4 showed 7.5 times (* p < 0.05) higher osteogenesis than in the untreated naïve cells, and HRH and HRHF4 fractions showed 22.6 times (*** p < 0.001) stronger osteogenesis activity than in the negative control. Osteoporosis was induced by excision of both ovaries in 9-week-old female ICR mice for in vivo analysis, and two active fractions, HRH and HRHF4, were administered orally for three months. During the oral administration period, body weight was measured weekly, and bone mineral density (BMD) and body fat density were measured simultaneously using a DEXA machine once a month. In particular, during the in vivo study, the average BMD of the ovariectomized group decreased by 0.0009 g/cm2, whereas the average BMD of the HRH intake group increased by 0.0033 g/cm2 (* p < 0.05) and that of the HRHF4 intake group increased by 0.0059 g/cm2 (** p < 0.01). The HRH and HRHF4 intake groups significantly recovered the mRNA and protein expression of osteogenic genes, including ALP, Osteopontin, Runx2, and Osterix, in the osteoporosis mouse tibia. These findings suggest that the active fractions of H. rhamnoides fruit significantly promoted osteoblast differentiation in mesenchymal stem cells and increased osteogenic gene expression, resulting in an improvement in bone mineral density in the osteoporosis mouse model. Taken together, H. rhamnoides fruits are promising candidates for the prevention and treatment of osteoporosis.

Abstract P3137: Drp1-dependent Mitochondrial Fission Induces Vascular Smooth Muscle Cell Dysfunction Through Kruppel-like Factor 4 Upregulation

Introduction: Vascular smooth muscle cell (VSMC) phenotypic switching and subsequent VSMC proliferation and migration are major events that are closely associated with progression of cardiovascular diseases. Mitochondria play key roles in regulation of cell function. Recent findings have revealed that mitochondrial fission promotes proliferation and migration of VSMCs. Hypothesis: This study aimed to explore the role of a new drug candidate, ginsenoside Rh1, in Angiotensin II (Ang II)-induced VSMC migration and proliferation and its underlying mechanisms. Methods: Sulforhodamine B and wound-healing assay were used to evaluate effects on cell proliferation and migration. Molecular mechanisms were investigated using western blotting, qRT-PCR analysis, immunofluorescence staining, and luciferase assay. Reactive oxygen species (ROS) production was measured by dihydroethidium and MitoSOX staining. Results: We found that pretreatment with 50 μM Rh1 significantly suppressed Ang II-induced cell proliferation (% of decrease vs. Ang II group: 17.41 ± 2.38%, p &lt; 0.01, n = 5) and migration (% of decrease vs. Ang II group: 198.8 ± 2.67%, p &lt; 0.001, n = 5). Concomitantly, Ang II-increased both protein and mRNA levels of MMP2, MMP9, PCNA, and cyclin D1 were reduced by Rh1 pretreatment. Rh1 incubation also reversed the changes in both protein and mRNA expressions of α-SMA, vimentin, and osteopontin induced by Ang II. Besides, Ang II enhanced protein expression and promoter activity of KLF4, a key regulator of phenotypic switching, whereas pretreatment with Rh1 reversed these effects. Mechanistically, inhibitory effects of Rh1 were found to be associated with inhibition of ERK1/2 signaling pathway and ROS generation. In addition, deactivation of ERK1/2 suppressed phosphorylation of DRP1 at Ser 616. Notably, inhibition of DRP1-dependent mitochondrial fission by Mdivi-1 inhibited KLF4 expression and transcriptional activity induced by Ang II. Conclusions: In conclusion, mitochondrial fission involves Ang II-induced VSMC proliferation and migration through KLF4 upregulation, and that Rh1 inhibits VSMC dysfunction by suppressing ROS-mediated ERK1/2/DRP1/KLF4 signaling pathway.

Tribulus terrestris L. extract ameliorates atherosclerosis by inhibition of vascular smooth muscle cell proliferation in ApoE−/− mice and A7r5 cells via suppression of Akt/MEK/ERK signaling

Ethnopharmacological relevanceAtherosclerosis (AS) is one of major threatens of death worldwide, and vascular smooth muscle cell (VSMC) proliferation is an important characteristic in the progression of AS. Tribulus terrestris L. is a well-known Chinese Materia Medica for treating skin pruritus, vertigo and cardiovascular diseases in traditional Chinese medicine. However, its anti-AS activity and inhibition effect on VSMC proliferation are not fully elucidated. AimsWe hypothesize that the furostanol saponins enriched extract (FSEE) of T. terrestris L. presents anti-AS effect by inhibition of VSMC proliferation. The molecular action mechanism underlying the anti-VSMC proliferation effect of FSEE is also investigated. Materials and methodsApolipoprotein-E deficient (ApoE−/−) mice and rat thoracic smooth muscle cell A7r5 were employed as the in vivo and in vitro models respectively to evaluate the anti- AS and VSMC proliferation effects of FSEE. In ApoE−/− mice, the amounts of total cholesterol, triglyceride, low density lipoprotein and high density lipoprotein in serum were measured by commercially available kits. The size of atherosclerotic plaque was observed by hematoxylin & eosin staining. The protein expressions of α-smooth muscle actin (α-SMA) and osteopontin (OPN) in the plaque were examined by immunohistochemistry. In A7r5 cells, the cell viability and proliferation were tested by MTT and Real Time Cell Analysis assays. The cell migration was evaluated by wound healing assay. Propidium iodide staining followed by flow cytometry was used to analyze the cell cycle progression. The expression of intracellular total and phosphorylated proteins including protein kinase B (Akt) and mitogen-activated protein kinases (MAPKs), such as mitogen-activated extracellular signal-regulated kinase (MEK), extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK), were detected by western blotting analysis. ResultsFSEE significantly reduced the area of atherosclerotic plaque in high-fat diet-fed ApoE−/− mice. And FSEE increased the protein expression level of α-SMA and decreased the level of OPN in atherosclerotic plaque, which revealed the inhibition of VSMC phenotype switching and proliferation. In A7r5 cells, FSEE suppressed fetal bovine serum (FBS) or oxidized low density lipoprotein (oxLDL)-triggered VSMC proliferation and migration in a concentration dependent manner. FSEE protected against the elevation of cell numbers in S phase induced by FBS or oxLDL and the reduction of cell numbers in G0/G1 phase induced by oxLDL. Moreover, the phosphorylation of Akt and MAPKs including MEK, ERK and JNK could be facilitated by FBS or oxLDL, while co-treatment of FSEE attenuated the phosphorylation of Akt induced by oxLDL as well as the phosphorylation of MEK and ERK induced by FBS. In addition, (25R)-terrestrinin B (JL-6), which was the main ingredient of FSEE, and its potential active pharmaceutical ingredients tigogenin (Tigo) and hecogenin (Heco) also significantly attenuated FBS or oxLDL-induced VSMC proliferation in A7r5 cells. ConclusionFSEE presents potent anti- AS and VSMC proliferation activities and the underlying mechanism is likely to the suppression of Akt/MEK/ERK signaling. The active components of FSEE are JL-6 and its potential active pharmaceutical ingredients Tigo and Heco. So, FSEE and its active compounds may be potential therapeutic drug candidates for AS.