BMP_2活性多肽/鼠尾Ⅰ型胶原复合物植入异位成骨的实验研究

用动物实验的方法验证鼠尾Ⅰ型胶原支架与自行研制合成的BMP2活性多肽复合后诱导异位成骨的能力与作用。自行提取鼠尾Ⅰ型胶原以及与BMP2活性多肽复合,冻干后低真空模式下电镜观察胶原结构。实验分2组。对照组:单纯鼠尾Ⅰ型胶原组;实验组:BMP2活性多肽/鼠尾Ⅰ型胶原复合物组。将12只大白鼠随机分成2组,每只大白鼠右侧大腿作2 cm的切口,制备股四头肌肌袋模型,将上述材料分别植入肌袋。术后第3周和第6周分别作放射学检查(X-ray,CT),第6周将所有大白鼠处死作组织学(HE染色)检查。鼠尾Ⅰ型胶原冻干后孔径大小合适与BMP2活性多肽复合后无明显改变。术后第3周和第6周放射学检查可见实验组有明显的钙化影形成,且第6周成骨范围要明显大于第3周时所见,而对照组无成骨现象。术后第6周组织学观察可见实验组植入区有成骨细胞和大量新骨形成,而对照组仅见炎性细胞改变。鼠尾Ⅰ型胶原是一种较好的载体支架材料,自行研制合成的BMP2活性多肽与其复合后,具有较强的异位诱导成骨能力。     

Soluble factors from neuronal cultures induce a specific proliferation and resistance to apoptosis of cognate mouse skeletal muscle precursor cells

The mechanisms or the physiological events, which control the regeneration of skeletal muscle through muscle precursor cell multiplication and differentiation, are still largely unknown. To address the question of the involvement of neurons in this process, skeletal muscle progenitors were grown in the presence of conditioned media obtained from 3-day-old cultures of embryonic neurons (derived from either the dorsal or the ventral region of 11-day-old mouse embryos) or media conditioned with satellite cells. Strikingly, only satellite cells cultured in medium conditioned from ventral embryonic neurons exhibited increased proliferation, as well as resistance to staurosporine (STS)-induced apoptosis. Our results suggest the existence of specific anti-apoptogenic neural soluble signals, which could be involved in skeletal muscle regeneration pathways.     

Non-coding RNAs regulate the BMP/Smad pathway during osteogenic differentiation of stem cells

MicroRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) are involved in the regulation of bone metabolism. The BMP/Smad pathway is a key signaling pathway for classical regulation of osteogenic differentiation. Non-coding RNAs (ncRNAs) and the BMP/Smad pathway both have important roles for osteogenic differentiation of stem cells, bone regeneration, and development of bone diseases. There is increasing evidence that ncRNAs interact with the BMP/Smad pathway to regulate not only osteogenic differentiation of stem cells but also progression of bone diseases, such as osteoporosis (OP), myeloma, and osteonecrosis of the femoral head (ONFH), by controlling the expression of bone disease-related genes. Therefore, ncRNAs that interact with BMP/Smad pathway molecules are potential targets for bone regeneration as well as bone disease diagnosis, prevention, and treatment. However, despite extensive studies on ncRNAs associated with the BMP/Smad pathway and osteogenic differentiation of stem cells, there is a lack of comparability. Moreover, some bone disease-associated ncRNAs with low abundance can be difficult to detect and there is a lack of mature delivery systems for their stable translocation to target sites, thus limiting their application. In this review, we summarize the research progress on interactions between ncRNAs and the BMP/Smad pathway during osteogenic differentiation of various stem cells and in the regulation of bone regeneration and bone diseases.     

Effects of differing oocyte-secreted factors during mouse in vitro maturation on subsequent embryo and fetal development

Purpose

We hypothesised that varying native oocyte-secreted factor (OSF) exposure or using different recombinant OSF peptides would have differential effects on post-in vitro maturation (IVM) embryo and fetal development.

Methods

Mouse cumulus oocyte complexes (COCs) were treated with the purified mature domain of GDF9 and/or BMP15 or were co-cultured with denuded oocytes (DOs) from 0 h or 3 h of IVM. DOs were matured for 3 h as either intact COCs+/-FSH before denuding, or as DOs + FSH. COCs were fertilised and blastocyst development was assessed on days 5 and 6, and either differentially stained for ICM numbers or vitrified/warmed embryos were transferred to recipients to assess implantation and fetal rates.

Results

No improvement in embryo development was observed with the addition of GDF9 and/or BMP15 to IVM. In contrast, embryos derived from COCs co-cultured with DOs had significantly improved blastocyst rates and ICM numbers compared to controls (P < 0.05). The highest response was obtained when DOs were first added to COCs at 3 h of IVM, after being pre-treated (0–3 h) as COCs + FSH. Compared to control, co-culture with DOs from 3 h did not affect implantation rates but more than doubled fetal yield (21 % vs 48 %; P < 0.05). GDF9 Western blot analysis was unable to detect any differences in quantity or form of GDF9 (17 and 65 kDa) in extracts of DO at 0 h or 3 h.

Conclusions

This study provides new knowledge on means to improve oocyte quality in vitro which has the potential to significantly aid human infertility treatment and animal embryo production technologies.     

应用BMP与FGF修复兔桡骨缺损的实验研究

目的 联合应用成骨及成血管的生长,探索治疗骨缺损的有效方法。方法 联合应用BMP+bFGF及单纯BMP复合去抗原异种松质骨,采用X线摄片及组织学方法检测两种方法修复兔桡骨2 cm缺损效果。结果 联合应用BMP+bFGF修复兔桡骨2 cm缺损在12周时缺损完全骨性连接,骨髓腔完全再通,明显优于单纯BMP组的修复效果(P<0.01)。结论 联合应用BMP+bFGF修复兔桡骨2 cm缺损在12周时缺损完全骨性连接,骨髓腔完全再通,能成为修复缺损的新的有效方法。     

组织工程方法异体骨复合物修复关节置换时骨缺损

目的：观察植入骨形态发生蛋白红骨髓异体骨复合物修复关节置换时骨缺损的疗效。方法：15例因多种疾患施行初次髋、膝或肩关节置换术，假体受区有骨包容性缺损需植骨。将骨形态发生蛋白、红骨髓、异体松质骨体外构建成复合物，即刻植入骨缺损区，然后再置入假体。结果：平均随访40个月。术后移植骨新骨替代较快，无吸收，骨缺损修复满意，假体无松动。结论：骨形态发生蛋白、红骨髓、异体骨构建成复合物，使坏死区成骨能力增强，可作为修复关节置换时骨缺损的一种选择。     

尺桡骨慢性骨髓炎应用抗感染活性骨Ⅰ期植骨治疗的疗效评价

目的验证抗感染活性骨(ARBX)Ⅰ期植骨治疗尺桡骨慢性骨髓炎的疗效。方法对2001年11月～2007年9月ARBXⅠ期植骨并获得16个月以上系统随访的尺桡骨慢性骨髓炎8例(10处)进行疗效分析。结果随访时间16～63个月,平均31个月。8例10处ARBX植骨中除1例残留骨不连,其余7例(9处)骨髓炎完全治愈:感染彻底控制无复发,骨不连、骨缺损获得骨修复。结论 ARBX具有高效诱导成骨活性和强效抗感染能力,在病灶彻底清除的基础上,能Ⅰ期植骨有效治疗尺桡骨慢性骨髓炎。     

The shift of macrophages toward M1 phenotype promotes aortic valvular calcification

Objective

The purpose of the present study was to comprehensively compare the phenotype profile of infiltrated macrophages in human noncalcified and calcific aortic valves, and to determine whether the shift of macrophage polarization modulates valvular calcification in vitro.

Disparate phospho-Smad2 levels in advanced type 2 diabetes patients with diabetic nephropathy and early experimental db/db mouse model

Uncontrolled activation of transforming growth factor beta (TGF-β) family members is hypothesized to participate in type 2 diabetes (T2D) dependent diabetic nephropathy (DN). We evaluated and compared downstream activation of the Smad2-signaling pathway in kidney samples from T2D patients to kidneys from the T2D model of leptin receptor deficient db/db mouse. Furthermore, expression of TGF-β family members was evaluated to elucidate molecular mechanisms in the mouse model. Kidney samples from patients with advanced stages of DN showed elevated pSmad2 staining whereas db/db mouse kidneys surprisingly showed a decrease in pSmad2 in the tubular compartment. Structurally, kidney tissue showed dilated tubules and expanded glomeruli, but no clear fibrotic pattern was found in the diabetic mice. Selective TGF-β family members were up-regulated at the mRNA level. Antagonists of bone morphogenetic protein (BMP) ligands, such as Gremlin1, USAG1 and Sclerostin, were strongly up-regulated suggesting a dampening effect on BMP pathways. Together, these results indicate a lack of translation from T2D patient kidneys to the db/db model with regards to Smad signaling pathway. It is plausible that a strong up-regulation of BMP antagonizing factors account for the lack of Smad1/5/8 activation, in spite of increased expression of several BMP members.     

Global gene profiling reveals a downregulation of BMP gene expression in experimental atrophic nonunions compared to standard healing fractures.

Nonunion is a challenging problem that may occur following certain bone fractures. However, there has been little investigation of the molecular basis of nonunions. Bone morphogenetic proteins (BMPs) play a significant role in osteogenesis. However, little is known about the expression patterns of BMPs in abnormal bone healing that results in nonunion formation. These facts prompted us to investigate and compare the gene expression patterns of BMPs and their antagonists in standard healing fractures and nonunions using rat experimental models. Standard closed healing fractures and experimental atrophic nonunions produced by periosteal cauterization at the fracture site were created in rat femurs. At postfracture days 3, 7, 10, 14, 21, and 28, total RNA was extracted from the callus of standard healing fracture and fibrous tissue of nonunion (n=4 per each time point and each group). Gene expression of BMPs, BMP antagonists, and other regulatory molecules were studied by methods including Genechip microarray and real-time quantitative RT-PCR. Gene expression of BMP-2, 3, 3B, 4, 6, 7, GDF-5, 7, and BMP antagonists noggin, drm, screlostin, and BAMBI were significantly lower in nonunions compared to standard healing fractures at several time points. Downregulation in expression of osteogenic BMPs may account for the nonunions of fracture. The balance between BMPs and their endogenous antagonists is critical for optimal fracture healing.