Increase In Osteopontin Levels Research Articles

#571 Vitamin D receptor from VSMCs regulates vascular calcification during CKD: a potential role for miR-145a

Abstract Background and Aims Vascular calcification (VC) is a highly prevalent complication of chronic kidney disease (CKD) and is associated with the higher morbidity-mortality of patients with CKD. Vitamin D receptor (VDR) has been proposed to play a role in the osteoblastic differentiation of vascular smooth muscle cells (VSMCs), but the involvement of vitamin D (1, 25D) in VC associated to CKD is controversial. Accumulating evidence points to microRNAs as important players in the process of VC and recent studies show that miR-145a expression decreases in VSMCs during VC. In addition, VDR has been considered as a potent regulator of these small molecules, while miR-145a was identified as a target for 1, 25D. Our aim was to determine the role of local vitamin D signalling in VSMCs during CKD-induced VC and the involvement of miR-145a in this process. Method We used epigastric arteries from CKD-affected patients and from individuals with normal renal function. In vivo, we employed an experimental model of CKD-induced VC in mice with conditional deletion of VDR in VSMC (Myh11-CreERT2+ VDRlox/lox), while in vitro, we used mouse VSMC with (VDRwt) or without VDR (VDRko) incubated in calcification media. Transfection experiments with mmu-miR-145a-5p mimic or mmu-miR-145a-5p inhibitor were carried out in mouse VDRwt VSMCs. Results CKD-affected patients showed an increase in VC, alongside an increased arterial expression of VDR compared with controls with normal renal function. Conditional gene silencing of VDR in arterial VSMCs led to a significant decrease of VC in the mouse model of CKD, despite similar levels of renal impairment and serum calcium and phosphate levels. This was accompanied by lower arterial expression of osteopontin (OPN) and lamin A, and a higher expression of sclerostin (SOST). Runx2 was increased in arteries of both CKD groups independently of the presence of VDR in VSMCs. Furthermore, CKD-affected mice showed a reduction of miR-145a expression in calcified arteries, which was significantly recovered in animals with deletion of VDR in VSMCs. In vitro, the absence of VDR prevented VC, inhibited the increase of OPN, and re-established the expression of miR-145a. Forced expression of miR-145a in vitro in VDRwt VSMCs blunted VC and decreased OPN levels. Mir-145a levels markedly decreased both in human and mouse VDRwt VSMCs incubated in calcification media and 1, 25D. Overexpression of miR-145a suppressed the levels of OPN induced by 1, 25D, while the inhibition of mir-145a led to a significant increase in OPN levels, even higher than in cells treated solely with 1, 25D. A predicted miR-145a-binding site was detected at the 3’UTR of OPN mRNA transcript, through the extended seed region of the miRNA, pointing to OPN as a possible target of mir-145a during VC in CKD. There were no significant differences in Runx2 levels in 1, 25D-treated cells after transfection with mir-145a mimic or inhibitor. Conclusion VDR is induced in calcified VSMCs during CKD where it can modulate the expression of promoters and inhibitors of VSMC transdifferentiation, as well as small noncoding RNA molecules such as mir-145a that modulate VC. The regulation of these pathways by VDR seems to be essential for the settings of CKD-induced VC, as deletion of VDR from VSMCs prevented it.

Surface topography of resorbable porcine collagen membranes, and their effect on early osteogenesis: An in vitro study

ObjectiveGuided tissue regeneration (GTR) is based on the use of different membranes that function as sealants and barriers in specific clinical situations. Among the several tissue production methods and origins, resorbable porcine-derived membranes are the most commonly used. Because these membranes are so diverse, and have several different clinical applications, doubts linger as to their effect in stimulating osteogenesis. The objective of this study was to make an in vitro evaluation of the viability and differentiation of osteoblastic cells cultured on the surface of the following collagen membranes: Jason® (Botiss Biomaterials), Collprotect® (Botiss Biomaterials), and Bio-Gide® (Geistlich). Material and methodsFragments of the 3 resorbable collagen membranes (5 × 5 mm) were used, and pre-osteoblastic SAOS-2 cells (ATCC, USA) were plated on their porous surfaces. Evaluation of the membranes was performed at 3, 5 and 7 days, considering the following parameters: (1) topographic analysis of the different surfaces by scanning electron microscope; (2) cellular viability by MTT, (3) quantification of type I collagen and osteopontin by Elisa. The quantitative analyses were carried out using a significance level of 5%. ResultsCollprotect® and Jason® membranes presented a rough surface with an irregular aspect on both sides, while double-layered Bio-Gide® had one layer with a smooth surface and the other with a rough surface along each respective length. The viability assays revealed that the cells cultured the cells grown on Collprotect® showed higher viability than those grown in Bio-Gide® or Jason®, especially after 5 and 7 days. After 3 and 5 days, evaluation of type I collagen showed that the cells plated on the Jason® and Collprotect® surfaces had greater collagen secretion than those plated on BioGide®. After 7 days, an increase in osteopontin levels was observed when the cells were plated on all the experimental membranes, compared with the control group. ConclusionAll the tested membranes were suitable for use in GTR clinical procedures. Their indication in specific regenerative cases depends on the mechanical and biological properties of their originating tissues, thus enabling better results and assertive choices by dental professionals.

PD11-04 LOSS OF OSTEOPONTIN LEADS TO THE RESOLUTION OF E. COLI-INDUCED PROSTATIC INFLAMMATION AND FIBROSIS

You have accessJournal of UrologyBenign Prostatic Hyperplasia: Basic Research & Pathophysiology (PD11)1 Sep 2021PD11-04 LOSS OF OSTEOPONTIN LEADS TO THE RESOLUTION OF E. COLI-INDUCED PROSTATIC INFLAMMATION AND FIBROSIS Petra Popovics, Asha Jain, Francesca Van, Hannah Ruetten, Mark Cadena, Kristen S. Uchtmann, Chad M. Vezina, and William A. Ricke Petra PopovicsPetra Popovics More articles by this author , Asha JainAsha Jain More articles by this author , Francesca VanFrancesca Van More articles by this author , Hannah RuettenHannah Ruetten More articles by this author , Mark CadenaMark Cadena More articles by this author , Kristen S. UchtmannKristen S. Uchtmann More articles by this author , Chad M. VezinaChad M. Vezina More articles by this author , and William A. RickeWilliam A. Ricke More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000001986.04AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Fibrogenic and inflammatory processes in the prostate are linked to the development of lower urinary tract symptoms (LUTS) in men, but the molecular mechanism is unknown. We previously established that osteopontin (OPN), a pro-fibrotic cytokine, is more abundant in the prostate of men with LUTS compared to prostate tissue with normal histology. We also identified that OPN secretion is stimulated by inflammatory cytokines in prostate stromal cells and hypothesized that OPN exacerbates the prostatic inflammatory environment. The current study investigates whether the lack of OPN ameliorates inflammation-induced prostatic fibrosis and urinary dysfunction in mice following transurethral instillation of E. coli. METHODS: Uropathogenic Escherichia coli (UTI89) or saline (control) was instilled via a transurethral catheter (OD 0.8, 100 ul) two times, 3 days apart to C57BL/6J (WT) or B6.129S6(Cg)-Spp1tm1Blh/J (OPN-KO) mice. Urinary function was assessed by weekly void spot assays (VSA). Prostatic collagen was visualized with picrosirius red (PSR) staining and inflammation by immunohistochemistry of the pan-leukocyte marker CD45. RNA-Seq analysis was performed from the ventral prostate lobe. RESULTS: Urinary frequency significantly increased (2.05-fold, p=0.0097) 33 days after E. coli instillation in WT but not in OPN-KO mice. One week after infection, the ventral and dorsal prostate lobes were significantly inflamed (more CD45 cells) and collagen fibers were thicker in both WT and OPN-KO mice. In contrast, 2 months after instillation, OPN-KO mouse prostates contained significantly less total collagen and inflammation compared to WT mice. RNAseq analysis identified that E. coli-instilled WT mice expressed more inflammatory and fibrotic marker RNAs, such as Col3a1, Il1b, MMP3, Mmp7 and Cxcl12 than OPN-KO mice. CONCLUSIONS: Our results show that by preventing the inflammation-related increase in OPN levels, mice undergo accelerated recovery from fibrosis and do not develop chronic inflammation. This suggests that drugs targeting OPN signaling could be beneficial for LUTS patients whose symptoms are primarily linked to fibrosis. Source of Funding: The study was supported by an NIH NIDDK K01 (K01DK127150) and a K12 award (K12DK100022-06, both to PP) and by U54 DK104310 (to WAR and CMV) © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e198-e199 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Petra Popovics More articles by this author Asha Jain More articles by this author Francesca Van More articles by this author Hannah Ruetten More articles by this author Mark Cadena More articles by this author Kristen S. Uchtmann More articles by this author Chad M. Vezina More articles by this author William A. Ricke More articles by this author Expand All Advertisement Loading ...

Impact of Valve Surgery on Serum Osteopontin Levels in Patients with Mitral Regurgitation

Objective: Osteopontin (OPN), a sialoprotein present within atherosclerotic lesions, especially in calcified plaques, is linked to the progression of coronary artery disease and heart failure. We assessed the impact of valve surgery on serum OPN and left ventricular (LV) function in patients with mitral regurgitation (MR). Methods: Thirty-two patients with severe MR scheduled for surgery were included in the study. Echocardiography markers were assessed preoperatively and at 3 months following the surgery and matched with the serum OPN levels. Results: Valve surgery was associated with a reduction of the ejection fraction (EF) from 55.2 ± 6.3 to 48.8 ± 7.1% after surgery, p < 0.001. Following surgery, the OPN level was significantly higher than preoperatively (mean 245, range 36-2,284 ng/ml vs. 76, 6-486 ng/ml, p = 0.007). Preoperative OPN exhibited a slight negative correlation with the EF (r = -0.35, p = 0.04), and a moderate correlation with vena contracta (r = -0.38, p = 0.02). There were no other meaningful correlations between conventional echocardiographic parameters and OPN. Conclusion: Following valve surgery due to severe MR, patients exhibited a decrease in EF and an increase in OPN levels. The assessment of preoperative OPN failed to strongly predict probable LV dysfunction.

Comparative effects of gastric bypass and sleeve gastrectomy on plasma osteopontin concentrations in humans

Bariatric surgery (BS) has proven to be an effective treatment for morbid obesity. Osteopontin (OPN) is a proinflammatory cytokine involved in the development of obesity. The aim of our study was to determine the effect of weight loss following BS on circulating levels of OPN in humans. Body composition and circulating concentrations of OPN and markers of bone metabolism were determined in obese patients who underwent Roux-en-Y gastric bypass (RYGB; n=40) or sleeve gastrectomy (SG; n=11). Patients who underwent RYGB or SG showed decreased body weight (P<0.001) and body fat percentage (P<0.001) as well as lower insulin resistance. However, plasma OPN levels were significantly increased after RYGB (P<0.001) but remained unchanged following SG (P=0.152). Patients who underwent RYGB also showed significantly increased C-terminal telopeptide of type-I collagen (ICTP) (P<0.01) and osteocalcin (P<0.001) while bone mineral density tended to decrease (P=0.086). Moreover, OPN concentrations were positively correlated with the bone resorption marker ICTP after surgery. On the other hand, patients who underwent SG showed significantly increased ICTP levels (P<0.05), and the change in OPN was positively correlated with the change in ICTP and negatively with the change in vitamin D after surgery (P<0.05). RYGB increased circulating OPN levels, while they remained unaltered after SG. The increase in OPN levels after RYGB could be related to the increased bone resorption in relation to its well-known effects on bone of this malabsorptive procedure in comparison to the merely restrictive SG.

Osteopontin Does Not Mitigate Cisplatin Ototoxicity or Nephrotoxicity in Adult Mice

The goal of this study was to determine whether osteopontin, a molecule with a variety of biologic effects including cell death inhibition, plays an important role in protection of the inner ear and kidney from the toxic effects of the chemotherapeutic drug cisplatin. In vivo study using a model system of cisplatin toxicity in adult mice. Virginia Merrill Bloedel Hearing Research Center, University of Washington. Osteopontin+/+ and Osteopontin-/- adult mice were treated with intraperitoneal cisplatin (20 mg/kg) or saline (control). Osteopontin levels were investigated by immunohistochemistry. Auditory brainstem response thresholds and cochlear histology were used to assess ototoxicity, while serum creatinine and renal histology were used to assess nephrotoxicity. For quantitative experiments, 8 to 18 animals were included in each treatment group. At 72 hours after cisplatin treatment, there was a slight increase in osteopontin levels within the kidney but not in the inner ear. There was no difference in auditory brainstem response threshold shifts, outer hair cell death, or serum creatinine between Osteopontin+/+ and Osteopontin-/- mice. Cochlear and renal histologic damage following cisplatin appeared to be similar in Osteopontin+/+ and Osteopontin-/- mice. Osteopontin is not required for development of normal auditory or renal function. Osteopontin is unlikely to play a role in protection of the inner ear or kidney from acute cisplatin toxicity. Slight increases in renal osteopontin 72 hours after cisplatin injury may be important for regeneration of proximal tubule cells.

175. Sleep and cytokines in early gestation: Possible mechanisms for adverse pregnancy outcomes

Systemic infection and inflammation in men are associated with bone loss. Rodent studies have elucidated the pathways mediating the effects of bacterial lipopolysaccharide (LPS), activated immune cells and hormones on bone. Here we investigate the changes in biochemical parameters of bone turnover following human endotoxemia, an experimental model of self-limiting systemic infection and inflammation.Ten healthy men received in a randomised, placebo-controlled, cross-over trial once placebo and once 2 ng/kg Escherichia coli endotoxin (LPS). During the following 6 h we monitored parathyoid hormone (PTH) and osteopontin (OPN), a multifunctional protein related to bone pathophysiology, as well as biochemical markers of bone turnover: C-terminal telopeptide of type I collagen (CTX), N-terminal propeptide of type I collagen (P1NP) and osteocalcin (OC). In LPS sessions there was a transient fall in PTH at 3 h (p = 0.009) and a nearly two-fold increase in OPN levels after 6 h (LPS: 155 ± 19 pg/ml; placebo: 85 ± 13 pg/ml, p < 0.001). LPS gradually reduced CTX levels (LPS: 0.44 ± 0.4 pg/ml; placebo: 0.59 ± 0.06 pg/ml, p = 0.003), P1NP showed a peak at 4 h (LPS: 89.9 ± 14.7 pg/ml; placebo: 75 ± 9.7 pg/ml, p = 0.028) and circulating OC did not change.The early human response to systemic endotoxemia boosts osteopontin levels and modifies bone biomarkers, indicating a decrease in the lytic activity of osteoclasts, accompanied by an increase in the activity of immature osteoblasts. These changes might present the acute phase response of immune and bone cells to bacterial stimuli in men.

Changes in osteopontin and in biomarkers of bone turnover during human endotoxemia

Systemic infection and inflammation in men are associated with bone loss. Rodent studies have elucidated the pathways mediating the effects of bacterial lipopolysaccharide (LPS), activated immune cells and hormones on bone. Here we investigate the changes in biochemical parameters of bone turnover following human endotoxemia, an experimental model of self-limiting systemic infection and inflammation. Ten healthy men received in a randomised, placebo-controlled, cross-over trial once placebo and once 2 ng/kg Escherichia coli endotoxin (LPS). During the following 6 h we monitored parathyoid hormone (PTH) and osteopontin (OPN), a multifunctional protein related to bone pathophysiology, as well as biochemical markers of bone turnover: C-terminal telopeptide of type I collagen (CTX), N-terminal propeptide of type I collagen (P1NP) and osteocalcin (OC). In LPS sessions there was a transient fall in PTH at 3 h ( p = 0.009) and a nearly two-fold increase in OPN levels after 6 h (LPS: 155 ± 19 pg/ml; placebo: 85 ± 13 pg/ml, p < 0.001). LPS gradually reduced CTX levels (LPS: 0.44 ± 0.4 pg/ml; placebo: 0.59 ± 0.06 pg/ml, p = 0.003), P1NP showed a peak at 4 h (LPS: 89.9 ± 14.7 pg/ml; placebo: 75 ± 9.7 pg/ml, p = 0.028) and circulating OC did not change. The early human response to systemic endotoxemia boosts osteopontin levels and modifies bone biomarkers, indicating a decrease in the lytic activity of osteoclasts, accompanied by an increase in the activity of immature osteoblasts. These changes might present the acute phase response of immune and bone cells to bacterial stimuli in men.

Oxidized low-density lipoprotein increases osteopontin expression by generation of oxidative stress

Osteopontin (OPN) is an important mediator of inflammation and is involved in the generation of atherosclerotic lesions. Oxidized LDL (OxLDL) increased the intracellular and secreted levels of OPN in rat smooth muscle cells in a dose- and time-dependent manner. Experiments with kinase inhibitors demonstrated that this effect was mediated by ERK and JNK, but not p38. OxLDL induced oxidative stress, measured by the intracellular levels of reactive oxygen species (ROS) and lipid peroxidation products. The increase in OPN levels was reproduced by the lipid extract of the particle and prevented by the antioxidant vitamin E. Furthermore, ROS generated by UVA irradiation or treatment with pro-oxidant compounds such as buthionine sulfoximine or H 2O 2 also enhanced intracellular and secreted OPN. Finally, OxLDL also augmented OPN levels in other cell types such as fibroblasts, keratinocytes, and endothelial cells. This work demonstrates the role of OxLDL in the expression of the OPN gene and further highlights the role of oxidative stress in the regulation of this cytokine. This might be related to the proinflammatory effects of OxLDL in the initiation and progression of atherosclerotic plaque.

Plasma levels of osteopontin before and 24 h after percutaneous coronary intervention

Objective: Previous studies demonstrated that osteopontin (OPN) was increased after vascular injury, such as atherosclerosis and restenosis following angioplasty. We sought to determine the effects of percutaneous coronary intervention (PCI) on plasma OPN levels compared with coronary arteriography (CA). Methods: Plasma OPN levels were determined in 103 patients who underwent CA or PCI with stent implantation, at baseline and 24 h after the procedure. Patients were divided into three groups; group I: patients without significant coronary artery stenosis, group II: patients with coronary artery disease in whom only CA was performed, group III: patients with coronary artery disease who had PCI and stent implantation. Results: Plasma OPN levels before the procedure were similar in all three groups. OPN levels 24 h after the procedure were significantly higher only in group III compared with baseline. Among three groups, the OPN levels observed in 24 h were significantly higher in group III compared with group I. Patients in group III had significantly higher OPN values after the procedure, depending on the number of stents implanted (p = 0.03). Conclusion: The increase in OPN levels after PCI suggests that vascular injury due to PCI is responsible for this phenomenon.

Osteopontin (OPN): A novel tumor marker of potential utility in metastatic breast cancer

575 Background: OPN, a secreted integrin-binding malignancy-associated protein measurable in blood and tumor tissue, has potential clinical utility as a tumor marker in breast cancer. Methods: In metastatic breast cancer, a prospective study to determine if (a) OPN blood levels are prognostic for survival (b) changes in OPN levels beyond baseline provide additional information (c) OPN has advantages over other blood markers (CEA, CA 15.3, secreted HER2 (ECD/HER2)). Blood was collected before treatment, and every 3–12 weeks until death. OPN: measured in plasma, using our validated ELISA assay (Clin. Bioch. 29:231, 1996). Serum markers: measured by standard clinical (CEA, CA 15.3), and ELISA (ECD/HER2) assays. Results: Study entry - 158 women within 8 weeks of diagnosis of metastatic breast cancer; median age 61 (20–84) years; postmenopausal (138); time to first metastasis 36 (0–397) months. First systemic treatment: chemotherapy (43), hormone therapy (111), none (4). Analysis July 2003: 132 (84% dead, median follow-up 19 (0.2–62) months. All 4 markers measured in 1378 samples (median 9 (1–26) per patient). OPN levels (median 177, range 1–2648) were elevated relative to previously determined normal levels. We used survival analysis with time-dependent covariates to investigate changes in OPN levels and survival (alive/dead) at 3, 6 and 12 months from final OPN measurement. These analyses show (i) the higher the initial OPN, the lower a patient's chance of being alive at 3 months (p=0.0005); 6 months (p=0.0142); 12 months (p=0.02) and (ii) controlling for initial OPN level, any increase in OPN levels between readings confers an increased risk of death at 3 months (RR 1.73, p=0.04); 6 months (RR 1.55, p=0.04); 12 months (RR 1.58, p=0.03). We will present further analyses comparing OPN with the 3 other tumor markers. Conclusions: In metastatic breast cancer, we found that OPN levels, both at baseline and changes over time, are prognostic for outcome. No significant financial relationships to disclose.

Osteopontin (OPN): A novel tumor marker of potential utility in metastatic breast cancer

575 Background: OPN, a secreted integrin-binding malignancy-associated protein measurable in blood and tumor tissue, has potential clinical utility as a tumor marker in breast cancer. Methods: In metastatic breast cancer, a prospective study to determine if (a) OPN blood levels are prognostic for survival (b) changes in OPN levels beyond baseline provide additional information (c) OPN has advantages over other blood markers (CEA, CA 15.3, secreted HER2 (ECD/HER2)). Blood was collected before treatment, and every 3–12 weeks until death. OPN: measured in plasma, using our validated ELISA assay (Clin. Bioch. 29:231, 1996). Serum markers: measured by standard clinical (CEA, CA 15.3), and ELISA (ECD/HER2) assays. Results: Study entry - 158 women within 8 weeks of diagnosis of metastatic breast cancer; median age 61 (20–84) years; postmenopausal (138); time to first metastasis 36 (0–397) months. First systemic treatment: chemotherapy (43), hormone therapy (111), none (4). Analysis July 2003: 132 (84% dead, median follow-up 19 (0.2–62) months. All 4 markers measured in 1378 samples (median 9 (1–26) per patient). OPN levels (median 177, range 1–2648) were elevated relative to previously determined normal levels. We used survival analysis with time-dependent covariates to investigate changes in OPN levels and survival (alive/dead) at 3, 6 and 12 months from final OPN measurement. These analyses show (i) the higher the initial OPN, the lower a patient's chance of being alive at 3 months (p=0.0005); 6 months (p=0.0142); 12 months (p=0.02) and (ii) controlling for initial OPN level, any increase in OPN levels between readings confers an increased risk of death at 3 months (RR 1.73, p=0.04); 6 months (RR 1.55, p=0.04); 12 months (RR 1.58, p=0.03). We will present further analyses comparing OPN with the 3 other tumor markers. Conclusions: In metastatic breast cancer, we found that OPN levels, both at baseline and changes over time, are prognostic for outcome. No significant financial relationships to disclose.

Plasma osteopontin levels are associated with the presence and extent of coronary artery disease

Recently, osteopontin (OPN) mRNA was reported to be highly expressed in atherosclerotic plaques, most strikingly in calcified plaques. We examined if plasma OPN levels are associated with coronary stenosis and calcification in patients with coronary artery disease (CAD). We measured plasma OPN levels in 178 patients undergoing coronary angiography. Compared with 71 patients without CAD, 107 with CAD had higher OPN levels (616±308 ng/ml versus 443±237 ng/ml, P<0.001). A stepwise increase in OPN levels was found depending on the number of >50% stenotic coronary vessels: 540±293 ng/ml in 1-vessel, 615±230 ng/ml in 2-vessel, and 758±416 ng/ml in 3-vessel disease. OPN levels also correlated with the numbers of >50% and >25% stenotic segments ( r=0.35 and 0.43, respectively, P<0.001). In multivariate analysis, OPN levels were significantly associated with CAD (odds ratio=1.21, 95% CI=1.05–1.39 for a 100 ng/ml increase) independent of traditional risk factors. Coronary calcification was found in 86 patients. OPN levels were higher in patients with calcification than in those without calcification (608±328 ng/ml versus 490±246 ng/ml, P<0.01) and correlated with the number of calcified segment ( r=0.26, P<0.001). However, OPN levels were not independently associated with coronary calcification. Thus, plasma OPN levels were found to be associated with the presence and extent of CAD.