{"id":{"repo_id":"iupui","oai_identifier":"oai:scholarworks.indianapolis.iu.edu:1805/12084"},"canonical_url":"https://search.dev.ndltd.org/etd/iupui/oai:scholarworks.indianapolis.iu.edu:1805/12084","repository":{"repo_id":"iupui","name":"IUPUI","base_url":"https://scholarworks.indianapolis.iu.edu/server/oai/request"},"display":{"title":"Regulation of osteoblast activity by Pyk2-targeted approaches","abstract":"The hormonal and cellular mechanisms controlling bone formation are not completely understood. The proline-rich tyrosine kinase 2 (Pyk2) is important for osteoblast (OB) activity and bone formation. However, female mice lacking Pyk2 (Pyk2-KO) exhibit elevated bone volume/total volume. Previously, our laboratory found ovariectomized Pyk2-KO mice supplemented with 17β-estradiol (E2) exhibited a greater increase in bone volume than WT mice treated with E2. The overall hypotheses of our studies are that Pyk2 regulates OB activity by modulating the E2-signaling cascade and that a Pyk2-inhibitor will promote OB activity and be suitable for bone regeneration applications. In Aim1, we determined the mechanism of action of Pyk2 and E2 in OBs. Pyk2-KO OBs showed significantly higher proliferation, matrix formation, and mineralization than WT OBs. In the presence of E2 or raloxifene, a selective estrogen receptor (ER) modulator, both matrix formation and mineralization were further increased in Pyk2-KO OBs, but not WT OBs. Consistent with a role of Pyk2 in E2 signaling, Pyk2-depletion led to the proteasome-mediated degradation of ERα, but not ERβ. Finally, we found Pyk2-depletion and E2 have an additive effect on ERK phosphorylation, known to increase cell differentiation and survival. In Aim2, we developed a Pyk2-inhibitor loaded hydrogel and evaluated its viscosity, gelation time, swelling, degradation, and release behavior. We found that a hydrogel composed of PEGDA1000 plus 10% gelatin exhibited viscosity and shear-thinning behavior suitable for use as an injectable-carrier. Importantly, the Pyk2-inhibitor-hydrogel was cytocompatible, retained its inhibitory activity against Pyk2 leading to an increase in OB activity. In conclusion, therapeutic strategies targeting Pyk2 may improve systemic bone formation, while Pyk2-inhibitor loaded hydrogels may be suitable for targeted bone regeneration in craniofacial and/or the other skeletal defects.","abstract_html":"The hormonal and cellular mechanisms controlling bone formation are not completely understood. The proline-rich tyrosine kinase 2 (Pyk2) is important for osteoblast (OB) activity and bone formation. However, female mice lacking Pyk2 (Pyk2-KO) exhibit elevated bone volume/total volume. Previously, our laboratory found ovariectomized Pyk2-KO mice supplemented with 17β-estradiol (E2) exhibited a greater increase in bone volume than WT mice treated with E2. The overall hypotheses of our studies are that Pyk2 regulates OB activity by modulating the E2-signaling cascade and that a Pyk2-inhibitor will promote OB activity and be suitable for bone regeneration applications. In Aim1, we determined the mechanism of action of Pyk2 and E2 in OBs. Pyk2-KO OBs showed significantly higher proliferation, matrix formation, and mineralization than WT OBs. In the presence of E2 or raloxifene, a selective estrogen receptor (ER) modulator, both matrix formation and mineralization were further increased in Pyk2-KO OBs, but not WT OBs. Consistent with a role of Pyk2 in E2 signaling, Pyk2-depletion led to the proteasome-mediated degradation of ERα, but not ERβ. Finally, we found Pyk2-depletion and E2 have an additive effect on ERK phosphorylation, known to increase cell differentiation and survival. In Aim2, we developed a Pyk2-inhibitor loaded hydrogel and evaluated its viscosity, gelation time, swelling, degradation, and release behavior. We found that a hydrogel composed of PEGDA1000 plus 10% gelatin exhibited viscosity and shear-thinning behavior suitable for use as an injectable-carrier. Importantly, the Pyk2-inhibitor-hydrogel was cytocompatible, retained its inhibitory activity against Pyk2 leading to an increase in OB activity. In conclusion, therapeutic strategies targeting Pyk2 may improve systemic bone formation, while Pyk2-inhibitor loaded hydrogels may be suitable for targeted bone regeneration in craniofacial and/or the other skeletal defects.","abstract_has_math":false,"creators":["Posritong, Sumana"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Bruzzaniti, Angela"],"committee_chairs":[],"committee_members":[],"year":2016,"date_issued":"2016-11-15","date_published":"2016-11-15","updated_at":"2026-07-24T02:40:46Z","subjects":["Pyk2","Bone formation","Estrogen","Estrogen receptor","Osteoblast"],"languages":["en_US"],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier.doi","label":"DOI","values":["10.7912/C2V31M"],"render_values":[{"text":"10.7912/C2V31M","href":"https://doi.org/10.7912/C2V31M","code":true}]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://dx.doi.org/10.7912/C2/1486"],"render_values":[{"text":"http://dx.doi.org/10.7912/C2/1486","href":"http://dx.doi.org/10.7912/C2/1486","code":true}]}]},"links":{"outbound_url":"https://hdl.handle.net/1805/12084","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Bruzzaniti, Angela"]},{"key":"dc:contributor.other","label":"Dc Contributor Other","values":["Chu, Tien-Min G.","Bottino, Marco C.","Li, Jiliang","Main, Russell P."]},{"key":"dc:creator","label":"Author","values":["Posritong, Sumana"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2017-03-20T18:13:33Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2019-03-02T10:30:14Z"]},{"key":"dc:date.issued","label":"Date","values":["2016-11-15"]},{"key":"dc:type","label":"Dc Type","values":["Dissertation"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Pyk2","Bone formation","Estrogen","Estrogen receptor","Osteoblast"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en_US"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.doi","label":"DOI","values":["10.7912/C2V31M"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://hdl.handle.net/1805/12084","http://dx.doi.org/10.7912/C2/1486"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Indiana University-Purdue University Indianapolis (IUPUI)"]},{"key":"dc:description.abstract","label":"Abstract","values":["The hormonal and cellular mechanisms controlling bone formation are not completely understood. The proline-rich tyrosine kinase 2 (Pyk2) is important for osteoblast (OB) activity and bone formation. However, female mice lacking Pyk2 (Pyk2-KO) exhibit elevated bone volume/total volume. Previously, our laboratory found ovariectomized Pyk2-KO mice supplemented with 17β-estradiol (E2) exhibited a greater increase in bone volume than WT mice treated with E2. The overall hypotheses of our studies are that Pyk2 regulates OB activity by modulating the E2-signaling cascade and that a Pyk2-inhibitor will promote OB activity and be suitable for bone regeneration applications. In Aim1, we determined the mechanism of action of Pyk2 and E2 in OBs. Pyk2-KO OBs showed significantly higher proliferation, matrix formation, and mineralization than WT OBs. In the presence of E2 or raloxifene, a selective estrogen receptor (ER) modulator, both matrix formation and mineralization were further increased in Pyk2-KO OBs, but not WT OBs. Consistent with a role of Pyk2 in E2 signaling, Pyk2-depletion led to the proteasome-mediated degradation of ERα, but not ERβ. Finally, we found Pyk2-depletion and E2 have an additive effect on ERK phosphorylation, known to increase cell differentiation and survival. In Aim2, we developed a Pyk2-inhibitor loaded hydrogel and evaluated its viscosity, gelation time, swelling, degradation, and release behavior. We found that a hydrogel composed of PEGDA1000 plus 10% gelatin exhibited viscosity and shear-thinning behavior suitable for use as an injectable-carrier. Importantly, the Pyk2-inhibitor-hydrogel was cytocompatible, retained its inhibitory activity against Pyk2 leading to an increase in OB activity. In conclusion, therapeutic strategies targeting Pyk2 may improve systemic bone formation, while Pyk2-inhibitor loaded hydrogels may be suitable for targeted bone regeneration in craniofacial and/or the other skeletal defects."]},{"key":"dc:title","label":"Title","values":["Regulation of osteoblast activity by Pyk2-targeted approaches"]}]}],"canonical_facts":{"dc:contributor.advisor":["Bruzzaniti, Angela"],"dc:contributor.other":["Chu, Tien-Min G.","Bottino, Marco C.","Li, Jiliang","Main, Russell P."],"dc:creator":["Posritong, Sumana"],"dc:date.accessioned":["2017-03-20T18:13:33Z"],"dc:date.available":["2019-03-02T10:30:14Z"],"dc:date.issued":["2016-11-15"],"dc:description":["Indiana University-Purdue University Indianapolis (IUPUI)"],"dc:description.abstract":["The hormonal and cellular mechanisms controlling bone formation are not completely understood. The proline-rich tyrosine kinase 2 (Pyk2) is important for osteoblast (OB) activity and bone formation. However, female mice lacking Pyk2 (Pyk2-KO) exhibit elevated bone volume/total volume. Previously, our laboratory found ovariectomized Pyk2-KO mice supplemented with 17β-estradiol (E2) exhibited a greater increase in bone volume than WT mice treated with E2. The overall hypotheses of our studies are that Pyk2 regulates OB activity by modulating the E2-signaling cascade and that a Pyk2-inhibitor will promote OB activity and be suitable for bone regeneration applications. In Aim1, we determined the mechanism of action of Pyk2 and E2 in OBs. Pyk2-KO OBs showed significantly higher proliferation, matrix formation, and mineralization than WT OBs. In the presence of E2 or raloxifene, a selective estrogen receptor (ER) modulator, both matrix formation and mineralization were further increased in Pyk2-KO OBs, but not WT OBs. Consistent with a role of Pyk2 in E2 signaling, Pyk2-depletion led to the proteasome-mediated degradation of ERα, but not ERβ. Finally, we found Pyk2-depletion and E2 have an additive effect on ERK phosphorylation, known to increase cell differentiation and survival. In Aim2, we developed a Pyk2-inhibitor loaded hydrogel and evaluated its viscosity, gelation time, swelling, degradation, and release behavior. We found that a hydrogel composed of PEGDA1000 plus 10% gelatin exhibited viscosity and shear-thinning behavior suitable for use as an injectable-carrier. Importantly, the Pyk2-inhibitor-hydrogel was cytocompatible, retained its inhibitory activity against Pyk2 leading to an increase in OB activity. In conclusion, therapeutic strategies targeting Pyk2 may improve systemic bone formation, while Pyk2-inhibitor loaded hydrogels may be suitable for targeted bone regeneration in craniofacial and/or the other skeletal defects."],"dc:identifier.doi":["10.7912/C2V31M"],"dc:identifier.uri":["https://hdl.handle.net/1805/12084","http://dx.doi.org/10.7912/C2/1486"],"dc:language.iso":["en_US"],"dc:subject":["Pyk2","Bone formation","Estrogen","Estrogen receptor","Osteoblast"],"dc:title":["Regulation of osteoblast activity by Pyk2-targeted approaches"],"dc:type":["Dissertation"]},"updated_at":"2026-07-24T02:40:46Z"}