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The pathogenesis of trauma-induced heterotopic ossification (HO) in the tendon remains unclear, posing a challenging hurdle in treatment. Recognizing inflammation as the root cause of HO, anti-inflammatory agents hold promise for its management. Malvidin (MA), possessing anti-inflammatory properties, emerges as a potential agent to impede HO progression. This study aimed to investigate the effect of MA in treating trauma-induced HO and unravel its underlying mechanisms. Herein, the effectiveness of MA in preventing HO formation was assessed through local injection in a rat model. The potential mechanism underlying MA's treatment was investigated in the tendon-resident progenitor cells of tendon-derived stem cells (TDSCs), exploring its pathway in HO formation. The findings demonstrated that MA effectively hindered the osteogenic differentiation of TDSCs by inhibiting the mTORC1 signalling pathway, consequently impeding the progression of trauma-induced HO of Achilles tendon in rats. Specifically, MA facilitated the degradation of Rheb through the K48-linked ubiquitination-proteasome pathway by modulating USP4 and intercepted the interaction between Rheb and the mTORC1 complex, thus inhibiting the mTORC1 signalling pathway. Hence, MA presents itself as a promising candidate for treating trauma-induced HO in the Achilles tendon, acting by targeting Rheb for degradation through the ubiquitin-proteasome pathway.
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Osificación Heterotópica , Complejo de la Endopetidasa Proteasomal , Proteína Homóloga de Ras Enriquecida en el Cerebro , Transducción de Señal , Ubiquitina , Animales , Ratas , Complejo de la Endopetidasa Proteasomal/metabolismo , Osificación Heterotópica/metabolismo , Osificación Heterotópica/etiología , Osificación Heterotópica/patología , Transducción de Señal/efectos de los fármacos , Proteína Homóloga de Ras Enriquecida en el Cerebro/metabolismo , Ubiquitina/metabolismo , Masculino , Osteogénesis/efectos de los fármacos , Tendones/metabolismo , Tendones/patología , Ratas Sprague-Dawley , Traumatismos de los Tendones/metabolismo , Traumatismos de los Tendones/patología , Traumatismos de los Tendones/complicaciones , Proteolisis/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Tendón Calcáneo/metabolismo , Tendón Calcáneo/patología , Tendón Calcáneo/lesiones , Modelos Animales de Enfermedad , Ubiquitinación , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Células Madre/metabolismo , Células Madre/efectos de los fármacosRESUMEN
Recombinant human bone morphogenetic protein-2 (rhBMP-2) has been FDA-approved for lumbar fusion, but supraphysiologic initial burst release due to suboptimal carrier and late excess bone resorption caused by osteoclast activation have limited its clinical usage. One strategy to mitigate the pro-osteoclast side effect of rhBMP-2 is to give systemic bisphosphonates, but it presents challenges with systemic side effects and low local bioavailability. The aim of this in vivo study was to analyze if posterolateral spinal fusion (PLF) could be improved by utilizing a calcium sulfate/hydroxyapatite (CaS/HA) carrier co-delivering rhBMP-2 and zoledronic acid (ZA). Six groups were allocated (CaS/HA, CaS/HA + BMP-2, CaS/HA + systemic ZA, CaS/HA + local ZA, CaS/HA + BMP-2 + systemic ZA, and CaS/HA + BMP-2 + local ZA). 10-week-old male Wistar rats, were randomly assigned to undergo L4-L5 PLF with implantation of group-dependent scaffolds. At 3 and 6 weeks, the animals were euthanized for radiography, µCT, histological staining, or biomechanical testing to evaluate spinal fusion. The results demonstrated that the CaS/HA biomaterial alone or in combination with local or systemic ZA didn't support PLF. However, the delivery of rhBMP-2 significantly promoted PLF. Combining systemic ZA with BMP-2 didn't enhance spinal fusion. Notably, the co-delivery of rhBMP-2 and ZA using the CaS/HA carrier significantly enhanced and accelerated PLF, without inhibiting systemic bone turnover, and potentially reduced the dose of rhBMP-2. Together, the treatment regimen of CaS/HA biomaterial co-delivering rhBMP-2 and ZA could potentially be a safe and cost-effective off-the-shelf bioactive bone substitute to enhance spinal fusion.
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BACKGROUND: Currently, there are no specific drugs or targets available for the treatment of tendinopathy. However, inflammation has recently been found to play a pivotal role in tendinopathy progression, thereby identifying it as a potential therapeutic target. Carpaine (CA) exhibits potential anti-inflammatory pharmacological properties and may offer a therapeutic option for tendinopathy. PURPOSE: This study aimed to investigate the effectiveness of CA in addressing tendinopathy and uncovering its underlying mechanisms. METHODS: Herein, the efficacy of CA by local administration in vivo in comparison to the first-line drug indomethacin was evaluated in a mouse collagenase-induced tendinopathy (CIT) model. Furthermore, IL-1ß induced a simulated pathological inflammatory microenvironment in tenocytes to investigate its underlying mechanisms in vitro. Further confirmation experiments were performed by overexpressing or knocking down the selective targets of CA in vivo. RESULTS: The findings demonstrated that CA was dose-dependent in treating tendinopathy and that the high-dose group outperformed the first-line drug indomethacin. Mechanistically, CA selectively bound to and enhanced the activity of the E3 ubiquitin ligase LRSAM1 in tendinopathy. This effect mediated the ubiquitination of p65 at lysine 93, subsequently promoting its proteasomal degradation. As a result, the NF-κB pathway was inactivated, leading to a reduction in inflammation of tendinopathy. Consequently, CA effectively mitigated the progression of tendinopathy. Moreover, the LRSAM1 overexpression demonstrated effectiveness in mitigating the tendinopathy progression and its knockdown abolished the therapeutic effects of CA. CONCLUSION: CA attenuates the progression of tendinopathy by promoting the ubiquitin-proteasomal degradation of p65 via increasing the enzyme activity of LRSAM1. The exploration of LRSAM1 has also unveiled a new potential target for treating tendinopathy based on the ubiquitin-proteasomal pathway.
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Alcaloides , Tendinopatía , Ubiquitina-Proteína Ligasas , Animales , Ratones , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina/metabolismo , Inflamación/metabolismo , Indometacina , Tendinopatía/tratamiento farmacológicoRESUMEN
Cement augmentation of pedicle screws is one of the most promising approaches to enhance the anchoring of screws in the osteoporotic spine. To date, there is no ideal cement for pedicle screw augmentation. The purpose of this study was to investigate whether an injectable, bioactive, and degradable calcium sulfate/hydroxyapatite (CaS/HA) cement could increase the maximum pull-out force of pedicle screws in osteoporotic vertebrae. Herein, 17 osteoporotic thoracic and lumbar vertebrae were obtained from a single fresh-frozen human cadaver and instrumented with fenestrated pedicle screws. The right screw in each vertebra was augmented with CaS/HA cement and the un-augmented left side served as a paired control. The cement distribution, interdigitation ability, and cement leakage were evaluated using radiographs. Furthermore, pull-out testing was used to evaluate the immediate mechanical effect of CaS/HA augmentation on the pedicle screws. The CaS/HA cement presented good distribution and interdigitation ability without leakage into the spinal canal. Augmentation significantly enhanced the maximum pull-out force of the pedicle screw in which the augmented side was 39.0% higher than the pedicle-screw-alone side. Therefore, the novel biodegradable biphasic CaS/HA cement could be a promising material for pedicle screw augmentation in the osteoporotic spine.
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Developing reactive oxygen species (ROS)-scavenging nanostructures to protect and regulate stem cells has emerged as an intriguing strategy for promoting tissue regeneration, especially in trauma microenvironments or refractory wounds. Here, an electronic modulated metal oxide is developed via Mn atom substitutions in Co3 O4 nanocrystalline (Mn-Co3 O4 ) for highly efficient and multifaceted catalytic ROS-scavenging to reverse the fates of mesenchymal stem cells (MSCs) in oxidative-stress microenvironments. Benefiting from the atomic Mn-substitution and charge transfer from Mn to Co, the Co site in Mn-Co3 O4 displays an increased ratio of Co2+ /Co3+ and improved redox properties, thus enhancing its intrinsic and broad-spectrum catalytic ROS-scavenging activities, which surpasses most of the currently reported metal oxides. Consequently, the Mn-Co3 O4 can efficiently protect the MSCs from ROS attack and rescue their functions, including adhesion, spreading, proliferation, and osteogenic differentiation. This work not only establishes an efficient material for catalytic ROS-scavenging in stem-cell-based therapeutics but also provides a new avenue to design biocatalytic metal oxides via modulation of electronic structure.
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Osteogénesis , Óxidos , Especies Reactivas de Oxígeno/metabolismo , Óxidos/química , Células Madre/metabolismo , ElectrónicaRESUMEN
To treat critical-size bone defects, composite materials and tissue-engineered bone grafts play important roles in bone repair materials. The purpose of this study was to investigate the bone regenerative potential of hybrid scaffolds consisting of macroporous calcium phosphate cement (CPC) and microporous mineralized collagen matrix (MCM). Hybrid scaffolds were synthetized by 3D plotting CPC and then filling with MCM (MCM-CPC group) and implanted into a 5 mm critical size femoral defect in rats. Defects left empty (control group) as well as defects treated with scaffolds made of CPC only (CPC group) and MCM only (MCM group) served as controls. Eight weeks after surgery, micro-computed tomography scans and histological analysis were performed to analyze the newly formed bone, the degree of defect healing and the activity of osteoclasts. Mechanical stability was tested by 3-point-bending of the explanted femora. Compared with the other groups, more newly formed bone was found within MCM-CPC scaffolds. The new bone tissue had a clamp-like structure which was fully connected to the hybrid scaffolds and thereby enhanced the biomechanical strength. Together, the biomimetic hybrid MCM-CPC scaffolds enhanced bone defect healing by improved osseointegration and their differentiated degradation provides spatial effects in the process of critical-bone defect healing.
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Biomimética , Andamios del Tejido , Animales , Cementos para Huesos/química , Cementos para Huesos/farmacología , Cementos para Huesos/uso terapéutico , Fosfatos de Calcio/química , Fosfatos de Calcio/farmacología , Colágeno/farmacología , Osteogénesis , Ratas , Andamios del Tejido/química , Microtomografía por Rayos XRESUMEN
METHODS: 60 patients with THFs were randomly and equally divided into the CPM group and non-CPM group. Both groups immediately received CPM and conventional physical therapies during hospitalization. After discharge, the non-CPM group was treated with conventional physical therapy alone, while the CPM group received conventional physical training in combination with CPM treatment. At 6 weeks and 6 months postoperatively, the primary outcome which was knee ROM and the secondary outcome which was knee functionality and quality of life were evaluated. RESULTS: The CPM group had a significantly increased ROM at both follow-up time points. The Knee Society Score, UCLA activity score, and the EuroQoL as well as the pain analysis showed significantly better results of the CPM group than the non-CPM group. CONCLUSIONS: The prolonged application of CPM therapy is an effective method to improve the postoperative rehabilitation of THFs.
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Terapia Pasiva Continua de Movimiento , Fracturas de la Tibia/rehabilitación , Fracturas de la Tibia/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Estudios Prospectivos , Calidad de Vida , Recuperación de la FunciónRESUMEN
BACKGROUND: While bone marrow-derived mesenchymal stromal cells (BM-MSCs) have been used for many years in bone tissue engineering applications, the procedure still has drawbacks such as painful collection methods and damage to the donor site. Dental pulp-derived stem cells (DPSCs) are readily accessible, occur in high amounts, and show a high proliferation and differentiation capability. Therefore, DPSCs may be a promising alternative for BM-MSCs to repair bone defects. OBJECTIVE: The aim of this study was to investigate the bone regenerative potential of DPSCs in comparison to BM-MSCs in vitro and in vivo. METHODS: In vitro investigations included analysis of cell doubling time as well as proliferation and osteogenic differentiation. For the in vivo study, 36 male NMRI nude mice were randomized into 3 groups: 1) control (cell-free mineralized collagen matrix (MCM) scaffold), 2) MCM + DPSCs, and 3) MCM + BMMSCs. Critical size 2 mm bone defects were created at the right femur of each mouse and stabilized by an external fixator. After 6 weeks, animals were euthanized, and microcomputed tomography scans (µCT) and histological analyses were performed. RESULTS: In vitro DPSCs showed a 2-fold lower population doubling time and a 9-fold higher increase in proliferation when seeded onto MCM scaffolds as compared to BM-MSCs, but DPSCs showed a significantly lower osteogenic capability than BM-MSCs. In vivo, the healing of the critical bone defect in NMRI nude mice was comparable among all groups. CONCLUSION: Pre-seeding of MCM scaffolds with DPSCs and BM-MSCs did not enhance bone defect healing.
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Células Madre Mesenquimatosas , Osteogénesis , Animales , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Pulpa Dental , Masculino , Ratones , Ratones Desnudos , Células Madre , Microtomografía por Rayos XRESUMEN
Orthopedic implant-associated infection constitutes one of the most devastating and challenging symptoms in the clinic. Implants without antimicrobial properties may become the harbourage for microbial colonization and biofilm formation, thus hindering normal bone regeneration processes. We had previously developed tannin modified HA (THA) as well as silver and tannin modified hydroxyapatite (HA) (Ag-THA) via a facile one-step and scalable process, and proven their antimicrobial performance in vitro. Herein, by compositing with non-antimicrobial polyurethane (PU), the in vivo anti-bacterial activity, osteoconductivity and osteoinductivity of PU/Ag-THA composite were investigated using an infected femoral condyle defect model on rat. PU/Ag-THA exhibited excellent in vivo antimicrobial activity, with the calculated bacteria fraction being reduced to lower than 3% at week 12 post operation. Meanwhile, PU/Ag-THA is also promising for bone regeneration under the bacteria challenge, evidenced by a final bone mineral density (BMD) ~0.6 times higher than that of the blank control at week 12. A continuous increase in BMD over time was observed in the PU/Ag-THA group, but not in the blank control and its non- or weak-antimicrobial counterparts (PU/HA and PU/THA), in which the growth rate of BMD declined after 8 weeks of operation. The enhanced osteoinductivity of PU/Ag-THA relative to blank control, PU/HA and PU/THA was also confirmed by the Runt-related transcription factor 2 (RUNX2) and osteocalcin (OCN) immunohistochemical staining. The above findings suggest that antimicrobial Ag-THA may serve as a promising and easy-to-produce antimicrobial mineral for the development of antimicrobial orthopedic composite implants to address the challenges in orthopedic surgeries, especially where infection may become a challenging condition to treat.
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Antiinfecciosos , Durapatita , Animales , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Antiinfecciosos/uso terapéutico , Regeneración Ósea , Durapatita/farmacología , Poliuretanos/farmacología , RatasRESUMEN
Biomaterial mediated bone regeneration is an attractive strategy for bone defect treatment. Organic/inorganic composites have been well established as effective bone graft. Here, the bone regenerative effect of the composites made from tannic acid (TA) modified hydroxyapatite (HA) (THA) or TA & silver nanoparticles (Ag NPs) modified HA (Ag-THA) and polyurethane (PU) was evaluated on critical-sized calvarial defects in rats. The in vivo study indicates that PU/THA and PU/Ag-THA scaffolds exhibited acceptable biocompatibility and induced significantly enhanced bone mineral densities comparing with the blank control (CON) group as well as PU/HA group. The inclusion of TA on HA brought the composites with enhanced osteogenesis and angiogenesis, evidenced by osteocalcin (OCN) and vascular endothelial growth factor (VEGF) immunohistochemical staining. Tartrate resistant acid phosphatase (TRAP) staining showed high osteoclast activity along with osteogenesis, especially in PU/THA and PU/Ag-THA groups. However, further introduction of Ag NPs on HA depressed the angiogenesis of the composites, leading to even lower VEGF expression than that of CON group. This study once more proved that THA can serve as a better bone composite component that pure HA and can promote osteogenesis and angiogenesis. While, the introduction of antimicrobial Ag NPs on HA need to be controlled in some extent not to affect the angiogenesis of the composites.
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PURPOSE: The occurrence of new vertebral compression fractures (VCFs) is a common complication after percutaneous kyphoplasty (PKP). Secondary VCFs after PKP occur predominantly in the thoracolumbar segment (T11 to L2). Prophylactic injections of cement into vertebral bodies in order to reduce new VCFs have rarely been reported. The main purpose of this study was to investigate whether prophylactically injecting cement into a nonfractured vertebral body at the thoracolumbar level (T11-L2) could reduce the occurrence of new VCFs. METHODS: From July 2011 to July 2018, PKP was performed in 86 consecutive patients with osteoporotic vertebral compression fractures (OVCFs) in the thoracolumbar region (T11-L2). All patients selected underwent PKP because of existing OVCFs (nonprophylactic group). Additionally, 78 consecutive patients with fractured vertebrae in the thoracolumbar region (T11-L2) with OVCFs underwent PKP and received prophylactic injections of cement into their nonfractured vertebrae in the thoracolumbar region (T11-L2) (prophylactic group). The visual analog scale (VAS) scores and incidence of new VCFs after PKP were compared between the two groups. RESULTS: The mean VAS scores improved from 8.00 ± 0.79 preoperatively to 1.62 ± 0.56 at the last follow-up in the nonprophylactic group and improved from 8.17 ± 0.84 to 1.76 ± 0.34 in the prophylactic group (P > 0.05). In the nonprophylactic group, 21 of 86 patients (24.4%) developed new VCFs within one year after PKP, of whom 15 patients (71.4%) developed VCFs within 3 months. In the prophylactic group, 8 of 78 patients (10.3%) developed new VCFs within one year, and 6 of these 8 patients (75%) developed new VCFs within 3 months. The incidence of new VCFs was significantly higher in the nonprophylactic group than that in the prophylactic group at one year (P = 0.018), but there were no statistically significant differences at three months (P = 0.847). CONCLUSIONS: Prophylactic injections of cement into nonfractured (T11-L2) vertebral bodies reduced the incidence of secondary VCFs after PKP in patients with OVCFs, but there was no significant difference in local back pain (VAS) scores between the two groups.
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Fracturas por Compresión/cirugía , Cifoplastia , Vértebras Lumbares/cirugía , Osteoporosis/cirugía , Fracturas Osteoporóticas/cirugía , Fracturas de la Columna Vertebral/cirugía , Vértebras Torácicas/cirugía , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
Hidden blood loss (HBL) plays an important role in perioperative rehabilitation of patients underwent posterior lumbar fusion surgery. This study was to calculate the volume of HBL and evaluate the risk factors among patients after posterior lumbar fusion surgery.A retrospective analysis was made on the clinical data of 143 patients underwent posterior lumbar fusion surgery from March 2017 to December 2017. Recording preoperative and postoperative hematocrit to calculate HBL according to Gross formula and analyzing its related factors including age, sex, height, weight, body mass index (BMI), surgery levels, surgical time, surgery types, duration of symptoms, disorder type, specific gravity of urine (SGU), plasma albumin (ALB), glomerular filtration rate (GFR), glucose (GLU), drainage volume, hypertension. Risk factors were further analyzed by multivariate linear regression analysis and t test.Eighty-six males and 57 females, mean age 52.7â±â11.4 years, mean height 162â±â7.0, mean weight 61.5â±â9.4, were included in this study. The HBL was 449â±â191âmL, with a percentage of 44.2%â±â16.6% in the total perioperative blood loss. Multivariate linear regression analysis revealed that patients with higher BMI (Pâ=â.026), PLIF procedures (Pâ=â.040), and more surgical time (Pâ=â.018) had a greater amount of HBL. Whereas age (Pâ=â0.713), sex (Pâ=â.276), surgery levels (Pâ=â.921), duration of symptoms (Pâ=â.801), disorder type (Pâ=â.511), SGU (Pâ=â.183), ALB (Pâ=â.478), GFR (Pâ=â.139), GLU (Pâ=â.423), hypertension (Pâ=â.337) were not statistically significant differences with HBL.HBL is a large proportion of total blood loss in patients after posterior lumbar fusion surgery. BMI >24âkg/m, PLIF procedures, and more surgical time are risk factors of HBL. Whereas age, sex, surgery levels, duration of symptoms, disorder type, SGU, ALB, GFR, GLU, hypertension were not associated with HBL.
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Pérdida de Sangre Quirúrgica/estadística & datos numéricos , Vértebras Lumbares/cirugía , Hemorragia Posoperatoria/epidemiología , Fusión Vertebral/efectos adversos , Fusión Vertebral/métodos , Adulto , Factores de Edad , Anciano , Índice de Masa Corporal , Pesos y Medidas Corporales , Femenino , Hematócrito , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Tempo Operativo , Estudios Retrospectivos , Factores de Riesgo , Factores SexualesRESUMEN
The purpose of this study was to calculate and compare the volume of hidden blood loss (HBL) and perioperative blood loss between open posterior lumbar interbody fusion (PLIF) and transforaminal lumbar interbody fusion (TLIF) by Wiltse approach.We retrospectively analyzed 143 patients between March 2017 and December 2017, they were randomly divided into PLIF group and TLIF group. The following information were collected on admission: patient's age, gender, height, weight, body mass index (BMI), surgery levels, surgical time, duration time, disorder type, intraoperative bleeding, wound drainage, visual analog scale (VAS) scores, neurological complications, transfusion rate. Preoperative and postoperative hematocrit (Hct) were recorded in order to calculate total blood loss (TBL) according to Gross's formula. To calculate each patient's HBL, chi-square test and Student's t test were used to analyze data.Patients in PLIF had a mean TBL of 1144â±â356âmL, and the mean HBL was 486â±â203âmL, 43.9â±â16.2% of the TBL. While patients in TLIF, the mean TBL was 952â±â303âmL, and the mean HBL was 421â±â178âmL, 44.7â±â17.0% of the TBL. Hence, there was significant difference in TBL and HBL between 2 groups, respectively (Pâ=â.000, Pâ=â.044). However, there was no difference in the ratio of the HBL between 2 groups (Pâ=â.797).The volume of HBL is lower in open TLIF by Wiltse approach than that in PLIF, which may be a large proportion of TBL in posterior lumbar fusion surgery. Comprehensive understanding of HBL can contribute to keep patient safety and better to rehabilitation in perioperative.
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Pérdida de Sangre Quirúrgica/estadística & datos numéricos , Vértebras Lumbares/cirugía , Fusión Vertebral/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Fusión Vertebral/estadística & datos numéricosRESUMEN
The reparative process following spinal cord injury (SCI) is extremely complicated. Cells in the microenvironment express multiple inhibitory factors that affect axonal regeneration over a prolonged period of time. The axon growth inhibitory factor glycogen synthase kinase-3 (GSK-3) is an important factor during these processes. TDZD-8 (4-benzyl-2-methyl-1,2,4-thiadiazolidine-3,5-dione) is the most effective and specific non-ATP-competitive inhibitor of GSK-3. Here, we show that administering TDZD-8 after SCI was associated with significantly inhibited neuronal apoptosis, upregulated GAP-43 expression, increased density of cortical spinal tract fibers around areas of injury, and increased Basso, Beattie, and Bresnahan (BBB) scores in the lower limbs. These findings support the notion that GSK-3 inhibitors promote neuronal cell regeneration and lower limb functional recovery.
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Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Regeneración Nerviosa/efectos de los fármacos , Traumatismos de la Médula Espinal/tratamiento farmacológico , Tiadiazoles/farmacología , Animales , Apoptosis/efectos de los fármacos , Axones/efectos de los fármacos , Modelos Animales de Enfermedad , Proteína GAP-43/genética , Regulación de la Expresión Génica/efectos de los fármacos , Glucógeno Sintasa Quinasa 3/genética , Humanos , Actividad Motora/efectos de los fármacos , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Ratas , Recuperación de la Función/efectos de los fármacos , Médula Espinal/fisiopatología , Traumatismos de la Médula Espinal/fisiopatologíaRESUMEN
Sweroside (SW), as a bioactive herbal ingredient, has anti-inflammatory effects. Protective effects of SW on IL-1ß-stimulated articular chondrocytes, however, has not been fully understood. This study was to explore the anti-inflammatory effects and further to investigate the possible mechanism underlying SW effect on IL-1ß-stimulated rat articular chondrocytes. Rat articular chondrocytes were cultured with or without SW for 1 h, and then stimulated with IL-1ß for 24 h. ELISA analysis was used to measure the production of NO and PGE2. Western blot was to detect the expression of iNOS and COX-2. Furthermore, the mRNA expression of MMP-1, MMP3, MMP13, and ADAMTS-5 were measured by q-PCR. These results demonstrated that SW significantly inhibited IL-1ß-induced NO and PGE2 production, as well as MMP-1, MMP3, MMP13, and ADAMTS-5 mRNA expression. Moreover, SW also suppressed IL-1ß-induced NF-κB activation and iκ-B degradation, S6K1 and S6 phosphorylation. In conclusion, these results strongly demonstrated that the anti-inflammatory activity of SW is in part mediated by suppressing NF-κB and mTORC1 signaling, which was expected to be a promising drug target of osteoarthritis therapy.
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Condrocitos/efectos de los fármacos , Inflamación/tratamiento farmacológico , Interleucina-1beta/efectos adversos , Glucósidos Iridoides/farmacología , Transducción de Señal/efectos de los fármacos , Animales , Antiinflamatorios/farmacología , Cartílago Articular , Dinoprostona/biosíntesis , Inflamación/inducido químicamente , Glucósidos Iridoides/uso terapéutico , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , FN-kappa B/metabolismo , Óxido Nítrico/biosíntesis , Plantas Medicinales/química , Sustancias Protectoras/farmacología , RatasRESUMEN
A comprehensive understanding of the key microenvironmental signals regulating bone regeneration is pivotal for the effective design of bioinspired orthopedic materials. Here, we identified citrate as an osteopromotive factor and revealed its metabonegenic role in mediating citrate metabolism and its downstream effects on the osteogenic differentiation of human mesenchymal stem cells (hMSCs). Our studies show that extracellular citrate uptake through solute carrier family 13, member 5 (SLC13a5) supports osteogenic differentiation via regulation of energy-producing metabolic pathways, leading to elevated cell energy status that fuels the high metabolic demands of hMSC osteodifferentiation. We next identified citrate and phosphoserine (PSer) as a synergistic pair in polymeric design, exhibiting concerted action not only in metabonegenic potential for orthopedic regeneration but also in facile reactivity in a fluorescent system for materials tracking and imaging. We designed a citrate/phosphoserine-based photoluminescent biodegradable polymer (BPLP-PSer), which was fabricated into BPLP-PSer/hydroxyapatite composite microparticulate scaffolds that demonstrated significant improvements in bone regeneration and tissue response in rat femoral-condyle and cranial-defect models. We believe that the present study may inspire the development of new generations of biomimetic biomaterials that better recapitulate the metabolic microenvironments of stem cells to meet the dynamic needs of cellular growth, differentiation, and maturation for use in tissue engineering.
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Ácido Cítrico/metabolismo , Células Madre Mesenquimatosas/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Materiales Biocompatibles/química , Biopolímeros/química , Regeneración Ósea/fisiología , Adhesión Celular , Diferenciación Celular/fisiología , Proliferación Celular , Modelos Animales de Enfermedad , Fracturas del Fémur/patología , Fracturas del Fémur/terapia , Humanos , Masculino , Células Madre Mesenquimatosas/citología , Redes y Vías Metabólicas , Modelos Biológicos , Osteogénesis/fisiología , Fenotipo , Fosfoserina/metabolismo , Ratas , Ratas Sprague-Dawley , Fracturas Craneales/patología , Fracturas Craneales/terapia , Nicho de Células Madre/fisiología , Simportadores/metabolismo , Ingeniería de Tejidos , Andamios del Tejido/químicaRESUMEN
BACKGROUND/AIMS: Narrowing of the lumbar spinal canal is a condition called lumbar spinal stenosis (LSS) and is a high-morbidity problem in the elderly. LSS is commonly caused by hypertrophy of the ligamentum flavum (HLF). Previous studies showed that fibrosis of the ligamentum flavum (LF) largely contributed to HLF. However, the underlying pathomechanism remains unclear. Insulin-like growth factor-1 (IGF-1) is known to have an intimate relationship with fibrosis in various tissues. Nevertheless, currently, there are few studies regarding IGF-1 in HLF. In this study, we investigated the role of IGF-1 in HLF and its potential molecular mechanism of action. METHODS: First, the IGF-1, phosphorylation of IGF-1 receptor (pIGF-1R), phosphorylation of AKT (pAKT), phosphorylation of S6(pS6), collagen I and collagen III expression levels were examined via immunohistochemistry and Western blotting in LF tissues from patients with LSS or Non-LSS. Second, primary LF cells were isolated from adults with a normal LF thickness and were cultured with different concentrations of IGF-1 with or without NVP-AEW541/rapamycin. RESULTS: The results showed that IGF-1, pIGF-1R, pAKT, pS6, collagen I and collagen III protein expression in the LSS group was significantly higher than that in the Non-LSS group. Meanwhile, pIGF-1R, pAKT, pS6, collagen I and collagen III protein expression was significantly enhanced in LF cells after IGF-1 exposure, which can be notably blocked by NVP-AEW541. In addition, pS6, collagen I and collagen III protein expression was blocked by rapamycin. CONCLUSIONS: Enhanced IGF-1 promotes the synthesis of collagen I and collagen III via the mTORC1 signaling pathway, which eventually contributes to hypertrophy of the ligamentum flavum.
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Hipertrofia/patología , Factor I del Crecimiento Similar a la Insulina/metabolismo , Ligamento Amarillo/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Transducción de Señal , Anciano , Estudios de Casos y Controles , Supervivencia Celular , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Femenino , Expresión Génica/efectos de los fármacos , Humanos , Ligamento Amarillo/citología , Ligamento Amarillo/diagnóstico por imagen , Masculino , Diana Mecanicista del Complejo 1 de la Rapamicina/antagonistas & inhibidores , Persona de Mediana Edad , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor IGF Tipo 1/metabolismo , Proteínas Quinasas S6 Ribosómicas/metabolismo , Transducción de Señal/efectos de los fármacos , Sirolimus/farmacologíaRESUMEN
High concentration of citrate exists in bone of humans and all osteo-vertebrates, and citrate incorporation imparts important biomechanical and other functional properties to bone. However, which cells are responsible for citrate production in bone remains unclear and whether the citrate component changes with bone loss during osteoporosis is also not known. Here, we show that the citrate content is markedly reduced in the bone of mice or rats with age-related, ovariectomy-induced or retinoic acid-induced bone loss. Plasmic citrate is also downregulated in osteoporotic animals. Importantly, the plasmic citrate level of aged osteoporotic males is significantly lower than that of young healthy males and positively correlates with human lumbar spine bone mineral density (BMD) and total hip BMD. Furthermore, citrate production increases with in vitro osteoblastic differentiation, accompanied by upregulation of proteins involved in citrate secretion, suggesting that osteoblasts are highly specialized cells that produce citrate in bone. Our findings establish a novel relationship between citrate content and bone loss-related diseases such as osteoporosis, suggesting a critical role of bone citrate in the maintenance of the citrate balance in the circulation. Serum citrate level may thus represent a novel marker for osteoporosis.
Asunto(s)
Densidad Ósea/fisiología , Ácido Cítrico/sangre , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/metabolismo , Osteoporosis/sangre , Osteoporosis/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Animales , Animales Recién Nacidos , Biomarcadores/sangre , Biomarcadores/metabolismo , Línea Celular , Ácido Cítrico/metabolismo , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratas , Ratas Sprague-Dawley , Adulto JovenRESUMEN
BACKGROUND: Tendon-bone healing is a reconstructive procedure which requires a tendon graft healing to a bone tunnel or to the surface of bone after the junction injury between tendon, ligament, and bone. The surgical reattachment of tendon to bone often fails due to regeneration failure of the specialized tendon-bone junction. MATERIALS AND METHODS: An extra-articular tendon-bone healing rat model was established to discuss the effect of the baicalein 10 mg/(kg·d) in accelerating tendon-bone healing progress. Also, tendon-derived stem cells (TDSCs) were treated with various concentrations of baicalein or dickkopf-1 (DKK-1) to stimulate differentiation for 14 days. RESULTS: In vivo, tendon-bone healing strength of experiment group was obviously stronger than the control group in 3 weeks as well as in 6 weeks. And there were more mature fibroblasts, more Sharpey fibers, and larger new bone formation area treated intragastrically with baicalein compared with rats that were treated with vehicle for 3 weeks and 6 weeks. In vitro, after induction for 14 days, the expressions of osteoblast differentiation markers, that is, alkaline phosphatase (ALP), runt-related transcription factor 2 (Runx2), osteocalcin (OCN), osterix (OSX), and collagen I, were upregulated and Wnt/ß-catenin signaling pathway was enhanced in TDSCs. The effect of DKK-1 significantly reduced the effect of baicalein on the osteogenic differentiation. CONCLUSION: These data suggest that baicalein may stimulate TDSCs osteogenic differentiation via activation of Wnt/ß-catenin signaling pathway to accelerate tendon-bone healing.
Asunto(s)
Huesos/efectos de los fármacos , Flavanonas/farmacología , Tendones/efectos de los fármacos , Vía de Señalización Wnt/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacos , beta Catenina/metabolismo , Fosfatasa Alcalina/metabolismo , Animales , Huesos/metabolismo , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Masculino , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteocalcina/efectos de los fármacos , Osteocalcina/metabolismo , Osteogénesis/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Células Madre/efectos de los fármacos , Células Madre/metabolismo , Tendones/metabolismoRESUMEN
Leptin, an adipocyte-derived cytokine associated with bone metabolism, is believed to play a critical role in the pathogenesis of heterotopic ossification (HO). The effect and underlying action mechanism of leptin were investigated on osteogenic differentiation of tendon-derived stem cells (TDSCs) in vitro and the HO formation in rat tendons. Isolated rat TDSCs were treated with various concentrations of leptin in the presence or absence of mTORC1 signaling specific inhibitor rapamycin in vitro. A rat model with Achilles tenotomy was employed to evaluate the effect of leptin on HO formation together with or without rapamycin treatment. In vitro studies with TDSCs showed that leptin increased the expression of osteogenic biomarkers (alkaline phosphatase, runt-related transcription factor 2, osterix, osteocalcin) and enhanced mineralization of TDSCs via activating the mTORC1 signal pathway (as indicated by phosphorylation of p70 ribosomal S6 kinase 1 and p70 ribosomal S6). However, mTORC1 signaling blockade with rapamycin treatment suppressed leptin-induced osteogenic differentiation and mineralization. In vivo studies showed that leptin promoted HO formation in the Achilles tendon after tenotomy, and rapamycin treatment blocked leptin-induced HO formation. In conclusion, leptin can promote TDSC osteogenic differentiation and heterotopic bone formation via mTORC1 signaling in both vitro and vivo model, which provides a new potential therapeutic target for HO prevention.