BACKGROUND:Bone morphogenetic protein 2 is vital in embryonic development,bone formation,and regeneration,but its high-dose application is linked to cancer.Bone morphogenetic protein 2 osteogenic peptide L20 reduces adverse effects like cancer and boosts bone tissue regeneration.OBJECTIVE:To graft bone morphogenetic protein 2 active peptide segments onto mesopores and surfaces through a peptide mimicry strategy inspired by oysters,and explore its impact on osteogenic properties of tissue-engineered bone.METHODS:(1)Mesoporous bioactive glass was synthesized using a template method.Bone morphogenetic protein 2 osteogenic peptide L20 was loaded onto mesoporous bioactive glass using a one-step synthesis method to characterize the morphology and in vitro sustained release properties of mesoporous active glass nanoparticles loaded with bone morphogenetic protein 2 osteogenic active peptide L20.(2)Bone marrow mesenchymal stem cells were isolated and extracted from SD rats.After two generations,they were co-cultured with PBS(blank group),mesoporous bioactive glass nanoparticles(control group),and mesoporous bioactive glass nanoparticles loaded with bone morphogenetic protein 2 osteogenic active peptide L20(experimental group).Cell live/dead fluorescence staining and CCK-8 assay were used to detect cytotoxicity and cell proliferation.Scanning electron microscopy was used to observe cell adhesion.After osteogenic induction and differentiation,alkaline phosphatase staining,Alizarin red S staining,and osteogenesis-related gene expression were detected.(3)Fifteen SD rats were selected to establish bilateral femoral condyle defect models and divided into three groups using a random number table method:the blank group(n=5)was not implanted with any material;the control group(n=5)was implanted with mesoporous bioactive glass nanoparticles,and the experimental group(n=5)was implanted with mesoporous bioactive glass nanoparticles loaded with bone morphogenetic protein 2 osteogenic active peptide L20.Eight weeks after surgery,femoral Micro-CT scanning and tissue morphology observation were performed.RESULTS AND CONCLUSION:(1)Scanning electron microscopy showed that the mesoporous bioactive glass nanoparticles loaded with bone morphogenetic protein 2 osteogenic active peptide L20 were spherical and monodisperse particles.Transmission electron microscopy showed their porous structure with an average particle size of(268.10±0.58)nm,which could release L20 in vitro.(2)Mesoporous bioglass nanoparticles loaded with bone morphogenetic protein 2 osteogenic active peptide L20 were non-cytotoxic and could promote the proliferation and adhesion of bone marrow mesenchymal stem cells.Compared with the blank group and the control group,the alkaline phosphatase activity and extracellular matrix mineralization capacity of the experimental group were increased(P<0.05),and the mRNA expression levels of alkaline phosphatase,Runx2,and osteocalcin were increased(P<0.05).(3)The results of femoral Micro-CT scanning showed that compared with the blank group and the control group,the new bone mass and bone density of the experimental group were increased(P<0.05).The results of hematoxylin-eosin and Masson staining showed that compared with the blank group and the control group,the new bone formation and collagen fibers of the experimental group were increased.(4)These findings indicate that mesoporous bioactive glass loaded with bone morphogenetic protein 2 active peptide L20 exhibits excellent biocompatibility and in vitro and in vivo osteogenic properties,promoting regeneration and repair of SD rat femoral condyle defects.

BACKGROUND:Bone morphogenetic protein 2 is vital in embryonic development,bone formation,and regeneration,but its high-dose application is linked to cancer.Bone morphogenetic protein 2 osteogenic peptide L20 reduces adverse effects like cancer and boosts bone tissue regeneration.OBJECTIVE:To graft bone morphogenetic protein 2 active peptide segments onto mesopores and surfaces through a peptide mimicry strategy inspired by oysters,and explore its impact on osteogenic properties of tissue-engineered bone.METHODS:(1)Mesoporous bioactive glass was synthesized using a template method.Bone morphogenetic protein 2 osteogenic peptide L20 was loaded onto mesoporous bioactive glass using a one-step synthesis method to characterize the morphology and in vitro sustained release properties of mesoporous active glass nanoparticles loaded with bone morphogenetic protein 2 osteogenic active peptide L20.(2)Bone marrow mesenchymal stem cells were isolated and extracted from SD rats.After two generations,they were co-cultured with PBS(blank group),mesoporous bioactive glass nanoparticles(control group),and mesoporous bioactive glass nanoparticles loaded with bone morphogenetic protein 2 osteogenic active peptide L20(experimental group).Cell live/dead fluorescence staining and CCK-8 assay were used to detect cytotoxicity and cell proliferation.Scanning electron microscopy was used to observe cell adhesion.After osteogenic induction and differentiation,alkaline phosphatase staining,Alizarin red S staining,and osteogenesis-related gene expression were detected.(3)Fifteen SD rats were selected to establish bilateral femoral condyle defect models and divided into three groups using a random number table method:the blank group(n=5)was not implanted with any material;the control group(n=5)was implanted with mesoporous bioactive glass nanoparticles,and the experimental group(n=5)was implanted with mesoporous bioactive glass nanoparticles loaded with bone morphogenetic protein 2 osteogenic active peptide L20.Eight weeks after surgery,femoral Micro-CT scanning and tissue morphology observation were performed.RESULTS AND CONCLUSION:(1)Scanning electron microscopy showed that the mesoporous bioactive glass nanoparticles loaded with bone morphogenetic protein 2 osteogenic active peptide L20 were spherical and monodisperse particles.Transmission electron microscopy showed their porous structure with an average particle size of(268.10±0.58)nm,which could release L20 in vitro.(2)Mesoporous bioglass nanoparticles loaded with bone morphogenetic protein 2 osteogenic active peptide L20 were non-cytotoxic and could promote the proliferation and adhesion of bone marrow mesenchymal stem cells.Compared with the blank group and the control group,the alkaline phosphatase activity and extracellular matrix mineralization capacity of the experimental group were increased(P<0.05),and the mRNA expression levels of alkaline phosphatase,Runx2,and osteocalcin were increased(P<0.05).(3)The results of femoral Micro-CT scanning showed that compared with the blank group and the control group,the new bone mass and bone density of the experimental group were increased(P<0.05).The results of hematoxylin-eosin and Masson staining showed that compared with the blank group and the control group,the new bone formation and collagen fibers of the experimental group were increased.(4)These findings indicate that mesoporous bioactive glass loaded with bone morphogenetic protein 2 active peptide L20 exhibits excellent biocompatibility and in vitro and in vivo osteogenic properties,promoting regeneration and repair of SD rat femoral condyle defects.

Cardiovascular diseases (CVDs) and metabolic disorders are major components of noncommunicable diseases, causing an enormous health and economic burden worldwide. There are common risk factors and developmental mechanisms among them, indicating the far-reaching significance in exploring the corresponding therapeutic targets. MST1/2 kinases are well-established proapoptotic effectors that also bidirectionally regulate autophagic activity. Recent studies have demonstrated that MST1/2 influence the outcome of cardiovascular and metabolic diseases by regulating immune inflammation. In addition, drug development against them is in full swing. In this review, we mainly describe the roles and mechanisms of MST1/2 in apoptosis and autophagy in cardiovascular and metabolic events as well as emphasis on the existing evidence for their involvement in immune inflammation. Moreover, we summarize the latest progress of pharmacotherapy targeting MST1/2 and propose a new mode of drug combination therapy, which may be beneficial to seek more effective strategies to prevent and treat CVDs and metabolic disorders.

Trichoderma reesei Rut-C30 is widely used in industrial cellulase production, and development of cellulase hyper-producer is of great importance for economic lignocellulosic biorefinery. In this study, T. reesei Rut-C30 was engineered with an artificial zinc finger proteins (AZFPs) library. Two mutants T. reesei M1 and M2 with improved cellulase production were obtained. Compared to the parent strain, the filter paper activity (FPase) of T. reesei M1 and M2 increased 100% and 53%, respectively. In addition, the total amount of extracellular protein from the M1 mutant increased 69%, whereas the endo-β-glucanase (CMCase) activity of the M2 mutant is 64% higher compared to the parental strain. Furthermore, RT-qPCR analysis showed that the major cellulase genes exhibited significantly increased expression in both mutants, but different patterns were observed in the two mutants. On the other hand, the cellulase transcriptional repressor ace1 was down-regulated in both mutants, but the transcription level of the activator xyr1 was only up-regulated in the strain M1. These results demonstrated that different AZFPs exert diverse regulatory mechanisms on cellulase production in T. reesei. Analysis of the target genes of AZFPs from T. reesei M1 and M2 will not only benefit further exploration of the regulatory mechanisms of cellulase biosynthesis in T. reesei, but also enable development of cellulase hyper-producing strains by metabolic engineering.
Cellulase ; Gene Library ; Transcription Factors ; Trichoderma ; Zinc Fingers

Objective To identify the expression of complement regulatory protein CD46, CD55, and CD59 on primary murine pallium astrocytes and the effect of inflammatory factors on it in order to lay the foundation for studying the complement system in AD. Methods The primary murine astrocytes were cultured and purified. The expression of CD46, CD55, and CD59 on the levels of mRNA and protein was assayed by immunofluorescence before and after the stimulation of LPS and IFN-?. Results The expression of CD59 mRNA was confirmed, but the expression of CD46 and CD55 was indefinite. There was no significant difference between stimulation and non-stimulation groups. Immunofluorescence results indicated that CD59 was positive, while CD46 and CD55 were weakly positive. Conclusion Protectin CD59 expresses copiously on primary murine astrocytes, which presumably protects astrocytes from the lysis of complement.