Steven Bain - Academia.edu (original) (raw)
Papers by Steven Bain
Heterotopic ossification (HO) is prevalent following orthopedic trauma, traumatic brain and spina... more Heterotopic ossification (HO) is prevalent following orthopedic trauma, traumatic brain and spinal cord injuries, brain, and limb amputations, particularly in combat veterans. HO causes pain, limited mobility and decreased quality of life. Current treatments are limited and have significant complications with high recurrence rates, underscoring the need for improved therapeutic interventions. In this study, we used genetically engineered osteoclasts (OCs) as a cell therapy to treat HO. Inducible, engineered myeloid precursors (iRANK cells) treated with chemical inducer of dimerization (CID) differentiated into TRAP+ multinucleated OCs, expressed functional osteopontin, and resorbed mineralized tissues in vitro. To investigate if iRANK OCs could reduce HO in vivo, HO lesions were induced by injections of BMP-2, and iRANK cells were locally delivered to ectopic bone nodules with concomitant systemic administration of CID. Micro-CT and histology showed that HO lesions were significantl...
The Journal of Nutrition, 1993
Skeletal growth and bone modeling in poultry are regulated by complex interactions between the an... more Skeletal growth and bone modeling in poultry are regulated by complex interactions between the animal's genetic potential and a host of systemic and localized factors (growth factors and cytokines) influencing bone biology. The objective of these interactions is to orchestrate the achievement of bone architecture that balances functionally appropriate morphology with the skeleton's involvement in mineral homeostasis. Within this context, bone modeling in the growing animal represents an adaptive process that is distinct from bone remodeling, which is the term used to describe the resorption and formation of mineralized tissue that maintains skeletal mass and morphology in the adult. As many of the skeletal lesions that afflict poultry are the consequence of abnormalities in bone modeling, not bone remodeling, an appreciation of the differences between these two contrasting processes is a prerequisite for understanding the pathogenesis of skeletal lesions in poultry.
The Anatomical Record, 1994
All known bone-derived osteoinductive factors have been isolated from endochondral (EC) bones and... more All known bone-derived osteoinductive factors have been isolated from endochondral (EC) bones and all initiate bone induction via EC ossification. However, to date no attempt has been made to isolate comparable factors from bones which form initially and completely via intramembranous (IM) ossification. The purpose of this work was to isolate osteoinductive proteins from IM bones. To accomplish this, we extracted proteins from bovine frontal bone matrix (intramembranous origin) using methods previously described for endochondral (EC) bone matrix (i.e., femur). Bone powder (<1 mm) was decalcified and proteins extracted with 4 M guanidine hydrochloride. Ultrafiltration was used to isolate and concentrate a 10-100 kilodalton (kDa) fraction, upon which heparin-Sepharose (HS) affinity chromatography was performed. HS-binding (HS-B) and nonbinding proteins (HS-NB) were lyophilized with bovine type I collagen (Vitrogen) to form pellets which were implanted subcutaneously in rats. Radiology as well as brightfield, fluorescent, and polarizing microscopy were used to assess the formation of ectopic bone at the site of pellet implantation. In this report we demonstrate that a heparin-Sepharose binding, osteoinductive factor can be extracted and partially purified from bovine intramembranous bone matrix. This factor has a different sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) banding pattern than a comparable osteoinductive/chondroinductive factor isolated from EC bone.
The FASEB Journal, 2012
A unilateral injection of botulinum toxin A (BTxA) in the calf induces paralysis and profound los... more A unilateral injection of botulinum toxin A (BTxA) in the calf induces paralysis and profound loss of ipsalateral trabecular bone within days. However, the cellular mechanism underlying acute muscle paralysis-induced bone loss (MPIBL) is poorly understood. We hypothesized that MPIBL arises via rapid and extensive osteoclastogenesis. We performed a series of in vivo experiments to explore this thesis. First, we observed elevated levels of the proosteoclastogenic cytokine receptor activator for nuclear factor-B ligand (RANKL) within the proximal tibia metaphysis at 7 d after muscle paralysis (؉113%, P<0.02). Accordingly, osteoclast numbers were increased 122% compared with the contralateral limb at 5 d after paralysis (P)40.0؍ and MPIBL was completely blocked by treatment with human recombinant osteoprotegerin (hrOPG). Further, conditional deletion of nuclear factor of activated T-cells c1 (NFATc1), the master regulator of osteoclastogenesis, completely inhibited trabecular bone loss (؊2.2؎11.9%, P<0.01). All experiments included negative control assessments of contralateral limbs and/or within-animal pre-and postintervention imaging. In summary, transient muscle paralysis induced acute RANKL-mediated osteoclastogenesis resulting in profound local bone resorption. Elucidation of the pathways that initiate osteoclastogenesis after paralysis may identify novel targets to inhibit bone loss and prevent fractures.
Nutrition Research, 1989
... EICOSANOIC FATTY ACIDS: RELATIONSHIP TO BIOTIN STATUS, PAIR-FEEDING, ANDTREADMILL EXERCISESte... more ... EICOSANOIC FATTY ACIDS: RELATIONSHIP TO BIOTIN STATUS, PAIR-FEEDING, ANDTREADMILL EXERCISESteven D. Bain 1,2 , Jarrett W. NewbreyI ... of Orthopaedics, HSC, T18-030, State University of New York @ StonyBrook, Stony Brook, NY 11794-8181.1229 1230 ...
Journal of Bone and Mineral Research, 1997
Considerable evidence supports the hypothesis that estrogen prevents bone loss by blocking the bo... more Considerable evidence supports the hypothesis that estrogen prevents bone loss by blocking the bone marrow cell production of pro-osteoclastogenic cytokines. However, controversy remains on the role of candidate factors, such as tumor necrosis factor (TNF) and interleukin-6 (IL-6). To investigate the contribution of these cytokines to the pathogenesis of ovariectomy (OVX)-induced bone loss, OVX mice were treated with either TNF binding protein (TNFbp), an inhibitor of TNF, the anti-(IL-6) antibody (Ab) 20F3, or estrogen for the first 2 weeks after surgery. OVX caused a rapid decrease in trabecular bone volume (TBV) and an increase in in vivo bone resorption, as assessed by bone histomorphometry. Treatment with TNFbp completely prevented bone loss and the increase in both osteoclast formation and bone resorption induced by OVX, but had no effects in sham-operated controls. In contrast, treatment with anti-IL-6 antibody failed to prevent bone loss, and the increase in bone resorption and osteoclastogenesis induced by OVX. These data demonstrate that in nongenetically manipulated mice, the estrogen-regulated cytokine that plays a central role in the mechanism by which estrogen deficiency causes bone loss is not IL-6, but rather TNF.
Journal of Bone and Mineral Research, 2009
The remodeling response of bone tissue to disuse in four normal adult male turkeys and four adult... more The remodeling response of bone tissue to disuse in four normal adult male turkeys and four adult males metabolically altered by castration was compared by functionally isolating the left ulna of each animal via transverse epiphyseal osteotomies. The right ulna in each animal was left intact and served as a control. After 8 weeks, the animals were euthanized, the ulnae harvested, and 100 pm undecalcified cross sections of the midshaft microradiographed. Areal properties, osteon mineral apposition rates from in vivo fluorochrome labels, and the number and ratios of bone-forming and bone-resorbing foci were quantitated. Compared to their control ulnae, the magnitude of bone resorbed from the functionally isolated ulnae of normal versus castrated males was not significantly different (-12.8 f 3.7 versus-10.7 f 3.5%, respectively). However, in the functionally isolated ulnae of normal birds, 94% of the total bone loss resulted from expansion of the corticoendosteal envelope, and 97% of the decrease in cross-sectional areas of the ulnae in the castrated birds was due to intracortical porosity. Furthermore, there was a significant interaction between disuse and castration, increasing the total number of intracortical remodeling events (9.4 f 0.9) when compared to disuse alone (4.7 f 1.4, p < 0.01), or to the intact ulnae of castrated (2.1 f 0.5) and normal adult males (2.0 f 1.1). This work emphasizes that the manner in which the bone tissue responds to local changes in its physical environment is directly dependent on the status of the organism's metabolic milieu.
Journal of Bone and Mineral Research, 2009
The temporal stages of lamellar bone formation were studied using an animal model subject to up t... more The temporal stages of lamellar bone formation were studied using an animal model subject to up to 16 weeks of a controlled, externally applied load. The left ulnae of 15 adult male turkeys were functionally isolated via transverse metaphyseal osteotomies, while transcutaneous Steinmann pins permitted in vivo loading of the preparation via a servo-hydraulic actuator. For 5 days per week, the ulnae were exposed to 100 cycles per day of an applied load sufficient to cause a peak strain normal to the bone's longitudinal axis of 2000 microstrain (p~). The contralateral limb was left surgically undisturbed and served as a baseline control. Following a loading period of 4,8, or 16 weeks, ulnae were harvested and prepared for quantitative bone histomorphometry. Compared with each animal's contralateral ulna, the area of the experimental ulnae increased by 12.5% (&5.6%) at 16 weeks. Periosteal mineral apposition rates in the loaded ulnae were significantly increased compared with control values, with a maximum rate of 6.0 f 3.4 p d d a y at 5 weeks, slowing to 2.0 2 0.3 p d d a y by 15 weeks. At 16 weeks, new bone was composed of primary and secondary osteons as well as circumferential lamellae, with osteocyte density and organization indistinguishable from that of the original cortex. Remnants of the initial woven bone response seen at 4 weeks remained clearly visible at both 8 and 16 weeks as diffusely labeled interstitial elements within the newly formed lamellar construct. The presence of secondary osteons, circumferential lamellae, and an osteocyte density and organization similar to that seen in controls suggests that the presence of woven bone in the initial stages of the adaptive process is not necessarily a pathologic or transient reaction to injury, but instead may be a normal stage in response to a potent mechanical stimulus.
Journal of Bone and Mineral Research, 2010
The phenotype of thrombospondin 2 (TSP2)-null mice includes abnormalities in collagen fibrils and... more The phenotype of thrombospondin 2 (TSP2)-null mice includes abnormalities in collagen fibrils and increases in ligamentous laxity, vascular density, and bleeding time. In this study, analyses by computerized tomography (CT) revealed that cortical density was increased in long bones of TSP2-null mice. Histomorphometric analysis showed that the mid-diaphyseal endosteal bone formation rate (BFR) of TSP2-null mice was increased in comparison with that of wild-type (WT) animals. Although microgeometric analysis showed that periosteal and endosteal radii were reduced, the mechanical properties of femurs from TSP2-null mice were not significantly different from those of controls, presumably because of the concomitant increase in endosteal bone mass. Bone loss in ovariectomized mice was equivalent for WT and mutant mice, a finding that indicates that TSP2-null animals are capable of normal bone resorption. To further explore the cellular basis for the increased endosteal BFR in TSP2-null mice, marrow stromal cells (MSCs) were isolated and examined in vitro. These cells were found to be present in increased numbers in a colony forming unit (CFU) assay and showed an increased rate of proliferation in vitro. We conclude that TSP2 regulates the proliferation of osteoblast progenitors, directly or indirectly, and that in its absence endosteal bone formation is increased.
Heterotopic ossification (HO) is prevalent following orthopedic trauma, traumatic brain and spina... more Heterotopic ossification (HO) is prevalent following orthopedic trauma, traumatic brain and spinal cord injuries, brain, and limb amputations, particularly in combat veterans. HO causes pain, limited mobility and decreased quality of life. Current treatments are limited and have significant complications with high recurrence rates, underscoring the need for improved therapeutic interventions. In this study, we used genetically engineered osteoclasts (OCs) as a cell therapy to treat HO. Inducible, engineered myeloid precursors (iRANK cells) treated with chemical inducer of dimerization (CID) differentiated into TRAP+ multinucleated OCs, expressed functional osteopontin, and resorbed mineralized tissues in vitro. To investigate if iRANK OCs could reduce HO in vivo, HO lesions were induced by injections of BMP-2, and iRANK cells were locally delivered to ectopic bone nodules with concomitant systemic administration of CID. Micro-CT and histology showed that HO lesions were significantl...
The Journal of Nutrition, 1993
Skeletal growth and bone modeling in poultry are regulated by complex interactions between the an... more Skeletal growth and bone modeling in poultry are regulated by complex interactions between the animal's genetic potential and a host of systemic and localized factors (growth factors and cytokines) influencing bone biology. The objective of these interactions is to orchestrate the achievement of bone architecture that balances functionally appropriate morphology with the skeleton's involvement in mineral homeostasis. Within this context, bone modeling in the growing animal represents an adaptive process that is distinct from bone remodeling, which is the term used to describe the resorption and formation of mineralized tissue that maintains skeletal mass and morphology in the adult. As many of the skeletal lesions that afflict poultry are the consequence of abnormalities in bone modeling, not bone remodeling, an appreciation of the differences between these two contrasting processes is a prerequisite for understanding the pathogenesis of skeletal lesions in poultry.
The Anatomical Record, 1994
All known bone-derived osteoinductive factors have been isolated from endochondral (EC) bones and... more All known bone-derived osteoinductive factors have been isolated from endochondral (EC) bones and all initiate bone induction via EC ossification. However, to date no attempt has been made to isolate comparable factors from bones which form initially and completely via intramembranous (IM) ossification. The purpose of this work was to isolate osteoinductive proteins from IM bones. To accomplish this, we extracted proteins from bovine frontal bone matrix (intramembranous origin) using methods previously described for endochondral (EC) bone matrix (i.e., femur). Bone powder (<1 mm) was decalcified and proteins extracted with 4 M guanidine hydrochloride. Ultrafiltration was used to isolate and concentrate a 10-100 kilodalton (kDa) fraction, upon which heparin-Sepharose (HS) affinity chromatography was performed. HS-binding (HS-B) and nonbinding proteins (HS-NB) were lyophilized with bovine type I collagen (Vitrogen) to form pellets which were implanted subcutaneously in rats. Radiology as well as brightfield, fluorescent, and polarizing microscopy were used to assess the formation of ectopic bone at the site of pellet implantation. In this report we demonstrate that a heparin-Sepharose binding, osteoinductive factor can be extracted and partially purified from bovine intramembranous bone matrix. This factor has a different sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) banding pattern than a comparable osteoinductive/chondroinductive factor isolated from EC bone.
The FASEB Journal, 2012
A unilateral injection of botulinum toxin A (BTxA) in the calf induces paralysis and profound los... more A unilateral injection of botulinum toxin A (BTxA) in the calf induces paralysis and profound loss of ipsalateral trabecular bone within days. However, the cellular mechanism underlying acute muscle paralysis-induced bone loss (MPIBL) is poorly understood. We hypothesized that MPIBL arises via rapid and extensive osteoclastogenesis. We performed a series of in vivo experiments to explore this thesis. First, we observed elevated levels of the proosteoclastogenic cytokine receptor activator for nuclear factor-B ligand (RANKL) within the proximal tibia metaphysis at 7 d after muscle paralysis (؉113%, P<0.02). Accordingly, osteoclast numbers were increased 122% compared with the contralateral limb at 5 d after paralysis (P)40.0؍ and MPIBL was completely blocked by treatment with human recombinant osteoprotegerin (hrOPG). Further, conditional deletion of nuclear factor of activated T-cells c1 (NFATc1), the master regulator of osteoclastogenesis, completely inhibited trabecular bone loss (؊2.2؎11.9%, P<0.01). All experiments included negative control assessments of contralateral limbs and/or within-animal pre-and postintervention imaging. In summary, transient muscle paralysis induced acute RANKL-mediated osteoclastogenesis resulting in profound local bone resorption. Elucidation of the pathways that initiate osteoclastogenesis after paralysis may identify novel targets to inhibit bone loss and prevent fractures.
Nutrition Research, 1989
... EICOSANOIC FATTY ACIDS: RELATIONSHIP TO BIOTIN STATUS, PAIR-FEEDING, ANDTREADMILL EXERCISESte... more ... EICOSANOIC FATTY ACIDS: RELATIONSHIP TO BIOTIN STATUS, PAIR-FEEDING, ANDTREADMILL EXERCISESteven D. Bain 1,2 , Jarrett W. NewbreyI ... of Orthopaedics, HSC, T18-030, State University of New York @ StonyBrook, Stony Brook, NY 11794-8181.1229 1230 ...
Journal of Bone and Mineral Research, 1997
Considerable evidence supports the hypothesis that estrogen prevents bone loss by blocking the bo... more Considerable evidence supports the hypothesis that estrogen prevents bone loss by blocking the bone marrow cell production of pro-osteoclastogenic cytokines. However, controversy remains on the role of candidate factors, such as tumor necrosis factor (TNF) and interleukin-6 (IL-6). To investigate the contribution of these cytokines to the pathogenesis of ovariectomy (OVX)-induced bone loss, OVX mice were treated with either TNF binding protein (TNFbp), an inhibitor of TNF, the anti-(IL-6) antibody (Ab) 20F3, or estrogen for the first 2 weeks after surgery. OVX caused a rapid decrease in trabecular bone volume (TBV) and an increase in in vivo bone resorption, as assessed by bone histomorphometry. Treatment with TNFbp completely prevented bone loss and the increase in both osteoclast formation and bone resorption induced by OVX, but had no effects in sham-operated controls. In contrast, treatment with anti-IL-6 antibody failed to prevent bone loss, and the increase in bone resorption and osteoclastogenesis induced by OVX. These data demonstrate that in nongenetically manipulated mice, the estrogen-regulated cytokine that plays a central role in the mechanism by which estrogen deficiency causes bone loss is not IL-6, but rather TNF.
Journal of Bone and Mineral Research, 2009
The remodeling response of bone tissue to disuse in four normal adult male turkeys and four adult... more The remodeling response of bone tissue to disuse in four normal adult male turkeys and four adult males metabolically altered by castration was compared by functionally isolating the left ulna of each animal via transverse epiphyseal osteotomies. The right ulna in each animal was left intact and served as a control. After 8 weeks, the animals were euthanized, the ulnae harvested, and 100 pm undecalcified cross sections of the midshaft microradiographed. Areal properties, osteon mineral apposition rates from in vivo fluorochrome labels, and the number and ratios of bone-forming and bone-resorbing foci were quantitated. Compared to their control ulnae, the magnitude of bone resorbed from the functionally isolated ulnae of normal versus castrated males was not significantly different (-12.8 f 3.7 versus-10.7 f 3.5%, respectively). However, in the functionally isolated ulnae of normal birds, 94% of the total bone loss resulted from expansion of the corticoendosteal envelope, and 97% of the decrease in cross-sectional areas of the ulnae in the castrated birds was due to intracortical porosity. Furthermore, there was a significant interaction between disuse and castration, increasing the total number of intracortical remodeling events (9.4 f 0.9) when compared to disuse alone (4.7 f 1.4, p < 0.01), or to the intact ulnae of castrated (2.1 f 0.5) and normal adult males (2.0 f 1.1). This work emphasizes that the manner in which the bone tissue responds to local changes in its physical environment is directly dependent on the status of the organism's metabolic milieu.
Journal of Bone and Mineral Research, 2009
The temporal stages of lamellar bone formation were studied using an animal model subject to up t... more The temporal stages of lamellar bone formation were studied using an animal model subject to up to 16 weeks of a controlled, externally applied load. The left ulnae of 15 adult male turkeys were functionally isolated via transverse metaphyseal osteotomies, while transcutaneous Steinmann pins permitted in vivo loading of the preparation via a servo-hydraulic actuator. For 5 days per week, the ulnae were exposed to 100 cycles per day of an applied load sufficient to cause a peak strain normal to the bone's longitudinal axis of 2000 microstrain (p~). The contralateral limb was left surgically undisturbed and served as a baseline control. Following a loading period of 4,8, or 16 weeks, ulnae were harvested and prepared for quantitative bone histomorphometry. Compared with each animal's contralateral ulna, the area of the experimental ulnae increased by 12.5% (&5.6%) at 16 weeks. Periosteal mineral apposition rates in the loaded ulnae were significantly increased compared with control values, with a maximum rate of 6.0 f 3.4 p d d a y at 5 weeks, slowing to 2.0 2 0.3 p d d a y by 15 weeks. At 16 weeks, new bone was composed of primary and secondary osteons as well as circumferential lamellae, with osteocyte density and organization indistinguishable from that of the original cortex. Remnants of the initial woven bone response seen at 4 weeks remained clearly visible at both 8 and 16 weeks as diffusely labeled interstitial elements within the newly formed lamellar construct. The presence of secondary osteons, circumferential lamellae, and an osteocyte density and organization similar to that seen in controls suggests that the presence of woven bone in the initial stages of the adaptive process is not necessarily a pathologic or transient reaction to injury, but instead may be a normal stage in response to a potent mechanical stimulus.
Journal of Bone and Mineral Research, 2010
The phenotype of thrombospondin 2 (TSP2)-null mice includes abnormalities in collagen fibrils and... more The phenotype of thrombospondin 2 (TSP2)-null mice includes abnormalities in collagen fibrils and increases in ligamentous laxity, vascular density, and bleeding time. In this study, analyses by computerized tomography (CT) revealed that cortical density was increased in long bones of TSP2-null mice. Histomorphometric analysis showed that the mid-diaphyseal endosteal bone formation rate (BFR) of TSP2-null mice was increased in comparison with that of wild-type (WT) animals. Although microgeometric analysis showed that periosteal and endosteal radii were reduced, the mechanical properties of femurs from TSP2-null mice were not significantly different from those of controls, presumably because of the concomitant increase in endosteal bone mass. Bone loss in ovariectomized mice was equivalent for WT and mutant mice, a finding that indicates that TSP2-null animals are capable of normal bone resorption. To further explore the cellular basis for the increased endosteal BFR in TSP2-null mice, marrow stromal cells (MSCs) were isolated and examined in vitro. These cells were found to be present in increased numbers in a colony forming unit (CFU) assay and showed an increased rate of proliferation in vitro. We conclude that TSP2 regulates the proliferation of osteoblast progenitors, directly or indirectly, and that in its absence endosteal bone formation is increased.