Changes in the tumor necrosis factor-α level after an ultrasound-guided femoral nerve block in elderly patients with a hip fracture / Alterações no nível de TNF-α após bloqueio do nervo femoral guiado por ultrassom em idosos com fratura de quadril

Abstract Background and objectives: An ultrasound guided femoral nerve block is an established analgesic method in patients with a hip fracture. Elevated cytokine levels correlate with poor patient outcomes after surgery. Hence, the aim of the study was to describe the levels of tumor necrosis factor-α after an ultrasound-guided femoral nerve block in elderly patients having a femoral neck fracture. Methods: A total of 32 patients were allocated into two treatment groups: 16 patients (femoral nerve block group; ultrasound-guided femoral nerve block with up to 20 mL of 0.3 mL.kg−1 of 0.5% bupivacaine and intravenous tramadol) and 16 patients (standard management group; up to 3 mL of 0.9% saline in the femoral sheath and intravenous tramadol). Tumor necrosis factor-α and visual analogue scale scores were evaluated immediately before the femoral nerve block and again at 4, 24, and 48 h after the femoral nerve block. All surgery was performed electively after 48 h of femoral nerve block. Results: The femoral nerve block group had a significantly lower mean tumor necrosis factor-α level at 24 (4.60 vs. 8.14, p < 0.001) and 48 h (5.05 vs. 8.56, p < 0.001) after the femoral nerve block, compared to the standard management group. The femoral nerve block group showed a significantly lower mean visual analogue scale score at 4 (3.63 vs. 7.06, p < 0.001) and 24 h (4.50 vs. 5.75, p < 0.001) after the femoral nerve block, compared to the standard management group. Conclusions: Ultrasound-guided femoral nerve block using 0.3 mL.kg−1 of 0.5% bupivacaine up to a maximum of 20 mL resulted in a significant lower tumor necrosis factor-α level.

Resumo Justificativa e objetivos: O bloqueio do nervo femoral guiado por ultrassom é um método analgésico estabelecido em pacientes com fratura de quadril. Níveis elevados de citocinas estão correlacionados com resultados desfavoráveis para o paciente após a cirurgia. Portanto, o objetivo do estudo foi descrever os níveis do fator de necrose tumoral alfa após bloqueio do nervo femoral guiado por ultrassom em pacientes idosos com fratura do colo de fêmur. Métodos: No total, 32 pacientes foram alocados em dois grupos de tratamento: 16 pacientes (grupo bloqueio do nervo femoral; bloqueio do nervo femoral guiado por ultrassom com até 20 mL de bupivacaína a 0,5% (0,3 mL.kg−1) e tramadol intravenoso) e 16 pacientes (grupo tratamento padrão, até 3 mL de solução salina a 0,9% na bainha femoral e tramadol intravenoso). Os escores do fator de necrose tumoral alfa e da Escala Visual Analógica foram avaliados imediatamente antes do bloqueio do nervo femoral e novamente em 4, 24 e 48 horas pós-bloqueio do nervo femoral. Todas as cirurgias foram realizadas de forma eletiva após 48 horas de bloqueio do nervo femoral. Resultados: O grupo bloqueio do nervo femoral teve um nível médio de fator de necrose tumoral alfa significativamente menor em 24 (4,60 vs. 8,14, p < 0,001) e 48 horas (5,05 vs. 8,56, p < 0,001) pós-bloqueio do nervo femoral, comparado com o grupo tratamento padrão. O grupo bloqueio do nervo femoral apresentou uma média significativamente menor no escore da Escala Visual Analógica em 4 (3,63 vs. 7,06, p < 0,001) e 24 horas (4,50 vs. 5,75, p < 0,001) pós-bloqueio do nervo femoral, em comparação com o grupo tratamento padrão. Conclusões: O bloqueio do nervo femoral guiado por ultrassom utilizando 0,3 mL.kg−1 de bupivacaína a 0,5% até o máximo de 20 mL resultou em um nível significativamente menor de fator de necrose tumoral alfa.

Rspo1 promotes osteoblast differentiation via Wnt signaling pathway.

R-spondin (Rspo)s proteins are a new group of Wnt/beta-catenin signaling agonists. These signaling molecules are known to be involved in the developmental stages of skeletal system. Recent studies in various murine osteoblast models have proposed that Rspo1 may interact with Wnt signaling pathway to induce differentiation in osteoblasts. Though findings in murine osteoblasts implicate a synergestic role of Rspo1 with Wnt signaling, still no study has addressed the similar role in more clinically applicable osteoblast models i.e., human cell lines or primary cells. Therefore, in the present study, we investigated the possible role of Rspo1 during differentiation process of human in vitro osteoblast cell models like primary osteoblasts or human osteoprogenitor cell line hFOB1.19 along with murine preosteoblast cell line MC3T3 E-1. Our results showed increase in Rspo1 at transcript level during differentiating phase of human primary osteoblasts and human FOB1.19 cells. We also found that Rspo1 (100 ng/mL) acts additively with Wnt3a to activate Wnt signaling, as confirmed by luciferase activity after transfection of TOPFLASH construct to hFOB1.19 cells. Similar additive role of Rspo1 and Wnt3a was apparent in alkaline phosphatase (ALP) activity analysis of human primary cells. Moreover, a reduction in ALP activity was observed with knock-down of Rspo1 by transfected shRNA in hFOB1.19 cells. These results suggested the possibility of autocrine regulation by Rspo1 on the osteogenic activities in human in vitro osteoblast models. Furthermore, these results were corroborated in MC3T3-E1, murine osteoblast cell model. Osteoblastic differentiation was induced by transfection of Rspo1 which was confirmed by increased ALP staining and qRT-PCR analysis of osteogenic markers, such as Runx2 and osteocalcin. In conclusion, present study highlights the role of Rspo1 in bone remodeling where it activates Wnt signaling to induce differentiation, as shown in human as well murine in vitro osteoblast cell models.