Ixazomib Modulates Bone Remodeling and Actives Sonic Hedgehog Pathways

Multiple myeloma (MM) is a clonal B-cell malignancy characterized by an accumulation of clonal plasma cells (PC) in the bone marrow (BM) leading to bone destruction and BM failure. Osteolytic bone disease is a common manifestation of MM that leads to progressive skeleton destruction and is the most severe cause of morbidity in MM patients. Pathogenetic mechanisms of MM bone destruction are closely linked to MM PC and osteoclasts (OCs) hyperactivity coupled with defective osteoblast (OB) function unable to counteract bone resorption. We recently demonstrated that the proteasome inhibitor (PI) Bortezomib, commonly used to treat MM, was capable to inhibit osteoclastic differentiation modulating chitinase family genes. In this work we investigated the effect of Ixazomib (IXA), a third generation PI, on osteoclastogenesis and osteogenic differentiation. Human monocytes were differentiated in OCs in presence of OC medium (supplemented with RANKL and M-CSF), and/or 10nM IXA. We observed that IXA was able to inhibit the expression of different OCs markers such as RANK, CTSK, TRAP, and MMP9 when added in OC medium in respect to OC medium alone (p<0.001). In addition, IXA treatment reduced CHIT1 enzymatic activity and downregulated CHIT1 and YKL40 (both mRNA and proteins). Immunofluorescence evaluation confirmed that IXA inhibited the mature OCs formation with five or more nuclei. Moreover, IXA was able to stimulate osteogenic differentiation of human mesenchymal stromal cells (MSCs). After 21 days of treatment, IXA alone or added to osteogenic medium increased the osteogenic markers genes (BMP2, RUNX2, Osteocalcin and Osteonectin). Immunofluorescence assay confirmed the increase of BMP2 after IXA treatment alone or in combination with osteogenic medium. Sonic Hedgehog (Shh) is one of the intricate signal transduction mechanisms that govern the precisely regulated developmental processes of multicellular organisms. Its signaling cascade plays an important role in bone homeostasis, and reducing Shh pathway protects against age-related bone loss. In this work we observed that IXA, but not Bortezomib, was able to bind the Smoothened (Smo) receptor which is the transducing molecule of the extracellular signal of Shh. Interestingly, using cellular thermal shift assay (CETSA), we demonstrated that IXA was able to bind directly Smo receptor activating the Shh cascade that leads to the nuclear translocation of Gli1 an effector of this pathway. Inhibiting Shh signaling by using an inhibitor of Smo activation (Cyclopamine), IXA-activated ostegenic differentiation-related genes were down-regulated. In conclusion, our data demonstrated that IXA regulates bone remodeling decreasing osteoclastogenesis and promoting osteogenic differentiation and therefore represents a good therapeutic option to improve the complex pathological condition of patients with MM. Disclosures Conticello: Celgene: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding. Palumbo:Amgen: Honoraria; Celgene: Honoraria; Hospira: Honoraria; Janssen: Honoraria; Novartis: Honoraria; Teva: Honoraria. Di Raimondo:Amgen: Consultancy, Honoraria, Research Funding; Takeda: Consultancy; Celgene: Consultancy, Honoraria, Research Funding.

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Ixazomib Improves Bone Remodeling and Counteracts Sonic Hedgehog Signaling Inhibition Mediated by Myeloma Cells

Cancers ◽

10.3390/cancers12020323 ◽

2020 ◽

Vol 12 (2) ◽

pp. 323 ◽

Cited By ~ 5

Author(s):

Daniele Tibullo ◽

Anna Longo ◽

Nunzio Vicario ◽

Alessandra Romano ◽

Alessandro Barbato ◽

...

Keyword(s):

Osteogenic Differentiation ◽

Bone Remodeling ◽

Sonic Hedgehog ◽

Bone Disease ◽

Human Mscs ◽

Bone Homeostasis ◽

Shh Signaling ◽

Shh Pathway ◽

Pathway Activation ◽

Osteolytic Bone Disease

Multiple myeloma (MM) is a clonal B-cell malignancy characterized by an accumulation of plasma cells (PC) in the bone marrow (BM), leading to bone loss and BM failure. Osteolytic bone disease is a common manifestation observed in MM patients and represents the most severe cause of morbidity, leading to progressive skeletal damage and disabilities. Pathogenetic mechanisms of MM bone disease are closely linked to PCs and osteoclast (OCs) hyperactivity, coupled with defective osteoblasts (OBs) function that is unable to counteract bone resorption. The aim of the present study was to investigate the effects of Ixazomib, a third-generation proteasome inhibitor, on osteoclastogenesis and osteogenic differentiation. We found that Ixazomib was able to reduce differentiation of human monocytes into OCs and to inhibit the expression of OC markers when added to the OC medium. Concurrently, Ixazomib was able to stimulate osteogenic differentiation of human mesenchymal stromal cells (MSCs), increasing osteogenic markers, either alone or in combination with the osteogenic medium. Given the key role of Sonic Hedgehog (SHH) signaling in bone homeostasis, we further investigated Ixazomib-induced SHH pathway activation. This set of experiments showed that Ixazomib, but not Bortezomib, was able to bind the Smoothened (SMO) receptor leading to nuclear translocation of GLI1 in human MSCs. Moreover, we demonstrated that PCs act as GLI1 suppressors on MSCs, thus reducing the potential of MSCs to differentiate in OBs. In conclusion, our data demonstrated that Ixazomib regulates bone remodeling by decreasing osteoclastogenesis and prompting osteoblast differentiation via the canonical SHH signaling pathway activation, thus, representing a promising therapeutic option to improve the complex pathological condition of MM patients.

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SUMO1 modification of IGF-1R combining with SNAI2 inhibited osteogenic differentiation of PDLSCs stimulated by high glucose

Stem Cell Research & Therapy ◽

10.1186/s13287-021-02618-w ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Rongrong Jiang ◽

Miao Wang ◽

Xiaobo Shen ◽

Shuai Huang ◽

Jianpeng Han ◽

...

Keyword(s):

Osteogenic Differentiation ◽

High Glucose ◽

Alveolar Bone ◽

Bone Destruction ◽

Major Complication ◽

Oral Disease ◽

Diabetic Patients ◽

Osteogenic Medium ◽

Periodontal Ligament Stem Cells ◽

Normal Glucose

Abstract Background Periodontal disease, an oral disease characterized by loss of alveolar bone and progressive teeth loss, is the sixth major complication of diabetes. It is spreading worldwide as it is difficult to be cured. The insulin-like growth factor 1 receptor (IGF-1R) plays an important role in regulating functional impairment associated with diabetes. However, it is unclear whether IGF-1R expression in periodontal tissue is related to alveolar bone destruction in diabetic patients. SUMO modification has been reported in various diseases and is associated with an increasing number of biological processes, but previous studies have not focused on diabetic periodontitis. This study aimed to explore the role of IGF-1R in osteogenic differentiation of periodontal ligament stem cells (PDLSCs) in high glucose and control the multiple downstream damage signal factors. Methods PDLSCs were isolated and cultured after extraction of impacted teeth from healthy donors or subtractive orthodontic extraction in adolescents. PDLSCs were cultured in the osteogenic medium with different glucose concentrations prepared by medical 5% sterile glucose solution. The effects of different glucose concentrations on the osteogenic differentiation ability of PDLSCs were studied at the genetic and cellular levels by staining assay, Western Blot, RT-PCR, Co-IP and cytofluorescence. Results We found that SNAI2, RUNX2 expression decreased in PDLSCs cultured in high glucose osteogenic medium compared with that in normal glucose osteogenic medium, which were osteogenesis-related marker. In addition, the IGF-1R expression, sumoylation of IGF-1R and osteogenic differentiation in PDLSCs cultured in high glucose osteogenic medium were not consistent with those cultured in normal glucose osteogenic medium. However, osteogenic differentiation of PDLCSs enhanced after adding IGF-1R inhibitors to high glucose osteogenic medium. Conclusion Our data demonstrated that SUMO1 modification of IGF-1R inhibited osteogenic differentiation of PDLSCs by binding to SNAI2 in high glucose environment, a key factor leading to alveolar bone loss in diabetic patients. Thus we could maximize the control of multiple downstream damage signaling factors and bring new hope for alveolar bone regeneration in diabetic patients.

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Loss of p53 in mesenchymal stem cells promotes alteration of bone remodeling through negative regulation of osteoprotegerin

Cell Death and Differentiation ◽

10.1038/s41418-020-0590-4 ◽

2020 ◽

Vol 28 (1) ◽

pp. 156-169

Author(s):

Tania Velletri ◽

Yin Huang ◽

Yu Wang ◽

Qing Li ◽

Mingyuan Hu ◽

...

Keyword(s):

Prostate Cancer ◽

Stem Cells ◽

Mesenchymal Stem Cells ◽

Bone Density ◽

Osteogenic Differentiation ◽

Bone Remodeling ◽

Bone Homeostasis ◽

Loss Of Function ◽

P53 Expression ◽

Receptor Activator

Abstractp53 plays a pivotal role in controlling the differentiation of mesenchymal stem cells (MSCs) by regulating genes involved in cell cycle and early steps of differentiation process. In the context of osteogenic differentiation of MSCs and bone homeostasis, the osteoprotegerin/receptor activator of NF-κB ligand/receptor activator of NF-κB (OPG/RANKL/RANK) axis is a critical signaling pathway. The absence or loss of function of p53 has been implicated in aberrant osteogenic differentiation of MSCs that results in higher bone formation versus erosion, leading to an unbalanced bone remodeling. Here, we show by microCT that mice with p53 deletion systemically or specifically in mesenchymal cells possess significantly higher bone density than their respective littermate controls. There is a negative correlation between p53 and OPG both in vivo by analysis of serum from p53+/+, p53+/−, and p53−/− mice and in vitro by p53 knockdown and ChIP assay in MSCs. Notably, high expression of Opg or its combination with low level of p53 are prominent features in clinical cancer lesion of osteosarcoma and prostate cancer respectively, which correlate with poor survival. Intra-bone marrow injection of prostate cancer cells, together with androgen can suppress p53 expression and enhance local Opg expression, leading to an enhancement of bone density. Our results support the notion that MSCs, as osteoblast progenitor cells and one major component of bone microenvironment, represent a cellular source of OPG, whose amount is regulated by the p53 status. It also highlights a key role for the p53-OPG axis in regulating the cancer associated bone remodeling.

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A Potential Role of Semaphorin 3A during Orthodontic Tooth Movement

International Journal of Molecular Sciences ◽

10.3390/ijms22158297 ◽

2021 ◽

Vol 22 (15) ◽

pp. 8297

Author(s):

Sinan Şen ◽

Christopher J. Lux ◽

Ralf Erber

Keyword(s):

Bone Remodeling ◽

Osteoblast Differentiation ◽

Tooth Movement ◽

Nuclear Translocation ◽

Marker Genes ◽

Bone Homeostasis ◽

Semaphorin 3A ◽

Osteogenic Marker ◽

Guidance Molecules ◽

Neuronal Guidance

Background: Induced tooth movement during orthodontic therapy requires mechano-induced bone remodeling. Besides various cytokines and growth-factors, neuronal guidance molecules gained attention for their roles in bone homeostasis and thus, potential roles during tooth movement. Several neuronal guidance molecules have been implicated in the regulation of bone remodeling. Amongst them, Semaphorin 3A is particular interesting as it concurrently induces osteoblast differentiation and disturbs osteoclast differentiation. Methods: Mechano-regulation of Sema3A and its receptors PlexinA1 and Neuropilin (RT-qPCR, WB) was evaluated by applying compressive and tension forces to primary human periodontal fibroblasts (hPDLF) and alveolar bone osteoblasts (hOB). The association of the transcription factor Osterix (SP7) and SEMA3A was studied by RT-qPCR. Mechanisms involved in SEMA3A-mediated osteoblast differentiation were assessed by Rac1GTPase pull-downs, β-catenin expression analyses (RT-qPCR) and nuclear translocation assays (IF). Osteogenic markers were analyzed by RT-qPCR. Results: SEMA3A, PLXNA1 and NRP1 were differentially regulated by tension or compressive forces in hPDLF. Osterix (SP7) displayed the same pattern of regulation. Recombinant Sema3A induced the activation of Rac1GTPase, the nuclear translocation of β-catenin and the expression of osteogenic marker genes. Conclusion: Sema3A, its receptors and Osterix are regulated by mechanical forces in hPDLF. SEMA3A upregulation was associated with Osterix (SP7) modulation. Sema3A-enhanced osteogenic marker gene expression in hOB might be dependent on a pathway involving Rac1GTPase and β-catenin. Thus, Semaphorin 3A might contribute to bone remodeling during induced tooth movement.

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Increased Sclerostin Secretion in Multiple Myeloma Plays a Central Role in Osteolytic Bone Disease

Blood ◽

10.1182/blood.v120.21.3989.3989 ◽

2012 ◽

Vol 120 (21) ◽

pp. 3989-3989

Author(s):

Homare Eda ◽

Loredana Santo ◽

Diana Cirstea ◽

Andrew J. Yee ◽

Anuj Mahindra ◽

...

Keyword(s):

Multiple Myeloma ◽

Mrna Expression ◽

Bone Disease ◽

Crucial Role ◽

Research Funding ◽

Neutralizing Antibody ◽

Bone Homeostasis ◽

Osteolytic Lesions ◽

Osteolytic Bone Disease

Abstract Abstract 3989 Bone Marrow Stromal Cells (BMSC), Osteoblasts (OB) and osteoclasts (OC) are a central part of the bone microenvironment and play a crucial role in multiple myeloma (MM) growth and survival. Their imbalance results in osteolytic lesions. Understanding the mechanisms underlying osteolytic lesions is important not only for the improvement of osteolytic bone disease but also for the treatment of MM. The osteocyte-secreted protein sclerostin, encoded by the SOST gene, is a potent inhibitor of osteoblastogenesis. However, the role of Sclerostin in MM remains to be elucidated. Our objective was to evaluate the role of sclerostin in MM bone disease and confirm that sclerostin directed strategies are an effective approach in MM. We observed higher levels of sclerostin in MM patients' plasma compared to leukemia patients, gastric cancer patients and healthy volunteers. Importantly, sclerostin levels were associated with an increase in tumor burden suggesting that MM cells are associated with the increase levels of sclerostin. Sclerostin concentrations similar to those detected in MM patients' plasma inhibited OB differentiation and an anti-sclerostin neutralizing antibody (R&D Systems) reversed this effect. Furthermore, sclerostin increased TRAP positive OC numbers differentiated from MM patients' peripheral blood mononuclear cell (PBMC) and their function as detected by pit formation assay. This was associated with stimulation of Ca2+/calmodulin-dependent protein kinases II (CaMKII) and c-Jun N-terminal kinase (JNK) signaling in preosteoclasts reversed by specific inhibitors with consequent inhibition of osteoclastogenesis. Moreover, sclerostin stimulated JNK and CaMKII phosphorylation, stimulated mRNA expression of RANKL and inhibited mRNA expression of OPG in MM patient derived BMSC. RANKL plays a crucial role in promoting OC differentiation and OPG, the decoy receptor for RANKL, inhibits OC differentiation; therefore our results indicate that sclerostin accelerates OC differentiation by JNK and CaMKII signaling stimulation in BMSC in addition to its direct affect against OC. We next examined OB derived from MM patients' BMSC cocultured with the MM cell line INA6 by using cell culture inserts to avoid cell-cell contact. INA6 inhibited OB differentiation and sclerostin neutralizing antibody reversed the INA6 effect as assessed by qPCR and alizarin red staining. Interestingly, co-culture with MM cells stimulated sclerostin mRNA expression and sclerostin protein expression in OB well as in OB cocultures with MM cells. Moreover recombinant CCL3 protein stimulated sclerostin mRNA expression in MM cells. Because CCL3 is secreted by MM cells, these data suggest in part the mechanism by which sclerostin is increased in MM-OB cocultures. These data suggest sclerostin is secreted by MM cells and OB and inhibits osteoblastogenesis and stimulates osteoclastogenesis directly and indirectly. Neutralizing sclerostin levels reverses these effects. Taken together, our data suggest that sclerostin is a good target to inhibit myeloma bone disease and help restore normal bone homeostasis. Disclosures: Raje: Onyx: Consultancy; Celgene: Consultancy; Millenium: Consultancy; Acetylon: Research Funding; Amgen: Research Funding; Eli-Lilly: Research Funding.

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Bone alkaline phosphatase and osteocalcin expression of rat's Gingival mesenchymal stem cells cultured in platelet-rich fibrin for bone remodeling (in vitro study)

European Journal of Dentistry ◽

10.4103/ejd.ejd_261_18 ◽

2018 ◽

Vol 12 (04) ◽

pp. 566-573 ◽

Cited By ~ 7

Author(s):

Alexander Patera Nugraha ◽

Ida Bagus Narmada ◽

Diah Savitri Ernawati ◽

Aristika Dinaryanti ◽

Eryk Hendrianto ◽

...

Keyword(s):

Alkaline Phosphatase ◽

Treatment Group ◽

Osteogenic Differentiation ◽

Bone Remodeling ◽

Bone Alkaline Phosphatase ◽

Male Rats ◽

Control Group ◽

Osteogenic Medium ◽

Significant Difference

ABSTRACT Objective: The aim of this study was to analyze the osteogenic differentiation of rat GMSCs cultured in PRF for bone remodeling. Materials and Methods: GMSCs were isolated from the lower gingival tissue of four healthy, 250 g, 1-month old, male rats (Rattus norvegicus) cut into small fragments, cultured for 2 weeks, and subsequently passaged every 4–5 days. GMSCs isolated in passage 3 were characterized by CD34, CD45, CD44, CD73, CD90, and CD105 using fluorescein isothiocyanate immunocytochemistry (ICC) examination. GMSCs in passage 3–5 cultured in five M24 plates (N = 108; n = 6/group) for 7, 14, and 21 days with three different mediums as follows: Control (−) group: α-Modified Eagle Medium; Control (+) group: High-dose glucose Dulbecco's Modified Eagle's Medium (DMEM-HG) + osteogenic medium; and treatment group: DMEM-HG + osteogenic medium + PRF. GMSCs were osteogenic differentiation cultured in vitro in three different mediums by bone alkaline phosphatase (BALP) and osteocalcin (OSC) marker using ICC monoclonal antibody. Statistical Analysis Used: The one-way analysis of variance was performed (P < 0.05) based on Shapiro–Wilk and Levene's tests (P > 0.05). Results: GMSCs were shown to present + CD44, +CD73, +CD90, +CD105 and − CD34, − and CD45 expression as MSCs markers. The treatment group showed the highest BALP expression (16.00 ± 1.732) on day 7, while OSC expression (13.67 ± 2.309) on day 21 showed the statistically significant difference between groups (P < 0.05). Conclusion: GMSCs cultured in PRF demonstrated potential osteogenic differentiation ability capable of accelerating in vitro bone remodeling by enhancing BALP and OSC expression.

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Increased Sclerostin Secretion in Multiple Myeloma Results in Stimulation of Osteoclastogenesis and Inhibition of Osteoblastogenesis

Blood ◽

10.1182/blood.v118.21.1819.1819 ◽

2011 ◽

Vol 118 (21) ◽

pp. 1819-1819

Author(s):

Homare Eda ◽

Loredana Santo ◽

Diana D. Cirstea ◽

Samantha Pozzi ◽

Miriam Canavese ◽

...

Keyword(s):

Multiple Myeloma ◽

Cell Line ◽

Board Of Directors ◽

Bone Disease ◽

Research Funding ◽

Plasma Concentrations ◽

Bone Homeostasis ◽

Advisory Committees ◽

Good Target ◽

Osteolytic Bone Disease

Abstract Abstract 1819 Objectives: Osteoblasts (OB) and osteoclasts (OC), are an integral part of the bone microenvironment, and play a crucial role in myeloma growth and survival. Their imbalance results in osteolytic disease and elucidating the mechanisms underlying osteolytic lesions is important not only for the improvement of osteolytic bone disease but also for the treatment of multiple myeloma (MM). The osteocyte-secreted protein sclerostin, encoded by the SOST gene, is a potent inhibitor of osteoblastogenesis. It is regarded as a good target for osteoporosis treatment, but its role in MM remains to be determined. Our objective was to study the role of sclerostin in MM bone disease and determine if sclerostin directed strategies were a reasonable approach in MM. Methods and Results: Sclerostin concentration in patients' blood plasma and MM cell line supernatant stimulated by IL-6, FGF-2, TNFalpha, BMP7 and TGFbeta was detected by ELISA (ALPCO immunoassays). Increased level of sclerostin was detected in MM patient plasma (n=20, median: 4.73 ng/mL, range: 1.5–19.5 ng/mL). Plasma concentrations were significantly higher (p<0.01) when compared to sclerostin concentration in the plasma of leukemia patients (n=3), gastric cancer patients (n=40) and healthy volunteers (n=4). High sclerostin levels were not associated with extent of bone disease but rather correlated with tumor burden (High B2M, creatinine and LDH, and low Hb) suggesting an autocrine loop for sclerostin production. Because sclerostin is derived from mature OB or orteocytes, we measured levels during OB differentiation but we were unable to detect increased levels. We then measured sclerostin levels in RPMI-8226 MM cell line supernatant either alone or stimulated by cytokines D Systems). Conclusions: These data demonstrate that increased sclerostin levels in MM patients inhibit osteoblastogenesis and stimulate osteoclastogenesis. Taken together, sclerostin may be good target to inhibit myeloma bone disease and help restore normal bone homeostasis. Disclosures: Raje: Celgene: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Millenium: Membership on an entity's Board of Directors or advisory committees; Astra Zeneca: Research Funding; Amgen: Membership on an entity's Board of Directors or advisory committees; Acetylon: Research Funding.

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Sonic Hedgehog and Triiodothyronine Pathway Interact in Mouse Embryonic Neural Stem Cells

International Journal of Molecular Sciences ◽

10.3390/ijms21103672 ◽

2020 ◽

Vol 21 (10) ◽

pp. 3672

Author(s):

Pavel Ostasov ◽

Jan Tuma ◽

Pavel Pitule ◽

Jiri Moravec ◽

Zbynek Houdek ◽

...

Keyword(s):

Stem Cells ◽

Neural Stem Cells ◽

Sonic Hedgehog ◽

Shh Pathway ◽

Proliferation Activity ◽

The Central Nervous System ◽

Beta Gene ◽

Potential Tool ◽

Receptor Beta ◽

Transplantation Therapy

Neural stem cells are fundamental to development of the central nervous system (CNS)—as well as its plasticity and regeneration—and represent a potential tool for neuro transplantation therapy and research. This study is focused on examination of the proliferation dynamic and fate of embryonic neural stem cells (eNSCs) under differentiating conditions. In this work, we analyzed eNSCs differentiating alone and in the presence of sonic hedgehog (SHH) or triiodothyronine (T3) which play an important role in the development of the CNS. We found that inhibition of the SHH pathway and activation of the T3 pathway increased cellular health and survival of differentiating eNSCs. In addition, T3 was able to increase the expression of the gene for the receptor smoothened (Smo), which is part of the SHH signaling cascade, while SHH increased the expression of the T3 receptor beta gene (Thrb). This might be the reason why the combination of SHH and T3 increased the expression of the thyroxine 5-deiodinase type III gene (Dio3), which inhibits T3 activity, which in turn affects cellular health and proliferation activity of eNSCs.

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Sonic Hedgehog modulates the inflammatory response and improves functional recovery after spinal cord injury in a thoracic contusion–compression model

European Spine Journal ◽

10.1007/s00586-021-06796-2 ◽

2021 ◽

Author(s):

Hao Zhang ◽

Alexander Younsi ◽

Guoli Zheng ◽

Mohamed Tail ◽

Anna-Kathrin Harms ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Sonic Hedgehog ◽

Functional Recovery ◽

Intrathecal Administration ◽

Neuroprotective Effects ◽

Thoracic Spinal Cord ◽

Shh Pathway ◽

Thoracic Spinal ◽

Cord Injury

Abstract Purpose The Sonic Hedgehog (Shh) pathway has been associated with a protective role after injury to the central nervous system (CNS). We, therefore, investigated the effects of intrathecal Shh-administration in the subacute phase after thoracic spinal cord injury (SCI) on secondary injury processes in rats. Methods Twenty-one Wistar rats were subjected to thoracic clip-contusion/compression SCI at T9. Animals were randomized into three treatment groups (Shh, Vehicle, Sham). Seven days after SCI, osmotic pumps were implanted for seven-day continuous intrathecal administration of Shh. Basso, Beattie and Bresnahan (BBB) score, Gridwalk test and bodyweight were weekly assessed. Animals were sacrificed six weeks after SCI and immunohistological analyses were conducted. The results were compared between groups and statistical analysis was performed (p < 0.05 was considered significant). Results The intrathecal administration of Shh led to significantly increased polarization of macrophages toward the anti-inflammatory M2-phenotype, significantly decreased T-lymphocytic invasion and significantly reduced resident microglia six weeks after the injury. Reactive astrogliosis was also significantly reduced while changes in size of the posttraumatic cyst as well as the overall macrophagic infiltration, although reduced, remained insignificant. Finally, with the administration of Shh, gain of bodyweight (216.6 ± 3.65 g vs. 230.4 ± 5.477 g; p = 0.0111) and BBB score (8.2 ± 0.2 vs. 5.9 ± 0.7 points; p = 0.0365) were significantly improved compared to untreated animals six weeks after SCI as well. Conclusion Intrathecal Shh-administration showed neuroprotective effects with attenuated neuroinflammation, reduced astrogliosis and improved functional recovery six weeks after severe contusion/compression SCI.

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