Advanced Biological Applications of Cerium Oxide Nanozymes in Disease Related to Oxidative Damage.

Due to their excellent catalytic activities, cerium oxide nanoparticles have promise as biological nanoenzymes. A redox reaction occurs between Ce3+ ions and Ce4+ ions during which they undergo conversion by acquiring or losing electrons as well as forming oxygen vacancies (or defects) in the lattice structure, which can act as antioxidant enzymes and simulate various enzyme activities. A number of cerium oxide nanoparticles have been engineered with multienzyme activities, including catalase, superoxide oxidase, peroxidase, and oxidase mimetic properties. Cerium oxide nanoparticles have nitric oxide radical clearing and radical scavenging properties and have been widely used in a number of fields of biology, including biomedicine, disease diagnosis, and treatment. This review provides a comprehensive introduction to the catalytic mechanisms and multiple enzyme activities of cerium oxide nanoparticles, along with their potential applications in the treatment of diseases of the brain, bones, nerves, and blood vessels.

Foxk1 stimulates adipogenic differentiation via a peroxisome proliferator-activated receptor gamma 2-dependent mechanism.

Adipogenesis is a tightly regulated process, and its dysfunction has been linked to metabolic disorders such as obesity. Forkhead box k1 (Foxk1) is known to play a role in the differentiation of myogenic precursor cells and tumorigenesis of different types of cancers; however, it is not clear whether and how it influences adipocyte differentiation. Here, we found that Foxk1 was induced in mouse primary bone marrow stromal cells (BMSCs) and established mesenchymal progenitor/stromal cell lines C3H/10T1/2 and ST2 after adipogenic treatment. In addition, obese db/db mice have higher Foxk1 expression in inguinal white adipose tissue than nonobese db/m mice. Foxk1 overexpression promoted adipogenic differentiation of C3H/10T1/2, ST2 cells and BMSCs, along with the enhanced expression of CCAAT/enhancer binding protein-α, peroxisome proliferator-activated receptor γ (Pparγ), and fatty acid binding protein 4. Moreover, Foxk1 overexpression enhanced the expression levels of lipogenic factors during adipogenic differentiation in both C3H/10T1/2 cells and BMSCs. Conversely, Foxk1 silencing impaired these cells from fully differentiating. Furthermore, adipogenic stimulation induced the nuclear translocation of Foxk1, which depended on the mTOR and PI3-kinase signaling pathways. Subsequently, Foxk1 is directly bound to the Pparγ2 promoter, stimulating its transcriptional activity and promoting adipocyte differentiation. Collectively, our study provides the first evidence that Foxk1 promotes adipocyte differentiation from progenitor cells by promoting nuclear translocation and upregulating the transcriptional activity of the Pparγ2 promoter during adipogenic differentiation.

miR-196b-5p Regulates Osteoblast and Osteoclast Differentiation and Bone Homeostasis by Targeting SEMA3A.

miR-196b-5p plays a role in various malignancies. We have recently reported its function in regulating adipogenesis. However, it remains to be clarified whether and how miR-196b-5p affects bone cells and bone homeostasis. In this study, in vitro functional experiments showed an inhibitory effect of miR-196b-5p on osteoblast differentiation. Mechanistic explorations revealed that miR-196b-5p directly targeted semaphorin 3a (Sema3a) and inhibited Wnt/ß-catenin signaling. SEMA3A attenuated the impaired osteogenesis induced by miR-196b-5p. Osteoblast-specific miR-196b transgenic mice showed significant reduction of bone mass. Trabecular osteoblasts were reduced and bone formation was suppressed, whereas osteoclasts, marrow adipocytes, and serum levels of bone resorption markers were increased in the transgenic mice. The osteoblastic progenitor cells from the transgenic mice had decreased SEMA3A levels and exhibited retarded osteogenic differentiation, whereas those marrow osteoclastic progenitors exhibited enhanced osteoclastogenic differentiation. miR-196b-5p and SEMA3A oppositely regulated the expression of receptor activator of nuclear factor-κB ligand and osteoprotegerin. The calvarial osteoblastic cells expressing the transgene promoted osteoclastogenesis, whereas the osteoblasts overexpressing Sema3a inhibited it. Finally, in vivo transfection of miR-196b-5p inhibitor to the marrow reduced ovariectomy-induced bone loss in mice. Our study has identified that miR-196b-5p plays a key role in osteoblast and osteoclast differentiation and regulates bone homeostasis. Inhibition of miR-196b-5p may be beneficial for amelioration of osteoporosis. © 2023 American Society for Bone and Mineral Research (ASBMR).

Metastasis suppressor 1 interacts with protein tyrosine phosphatase receptor-δ to regulate adipogenesis.

Adipogenesis is a finely controlled process and its dysfunction may contribute to metabolic disorders such as obesity. Metastasis suppressor 1 (MTSS1) is a player in tumorigenesis and metastasis of various types of cancers. To date, it is not known whether and how MTSS1 plays a role in adipocyte differentiation. In the current study, we found that MTSS1 was upregulated during adipogenic differentiation of established mesenchymal cell lines and primary cultured bone marrow stromal cells. Gain-of-function and loss-of-function experiments uncovered that MTSS1 facilitated adipocyte differentiation from mesenchymal progenitor cells. Mechanistic explorations revealed that MTSS1 bound and interacted with FYN, a member of Src family of tyrosine kinases (SFKs), and protein tyrosine phosphatase receptor-δ (PTPRD). We demonstrated that PTPRD was capable of inducing the differentiation of adipocytes. Overexpression of PTPRD attenuated the impaired adipogenesis induced by the siRNA targeting MTSS1. Both MTSS1 and PTPRD activated SFKs by suppressing the phosphorylation of SFKs at Tyr530 and inducing the phosphorylation of FYN at Tyr419. Further investigation showed that MTSS1 and PTPRD were able to activate FYN. Collectively, our study has for the first time unraveled that MTSS1 plays a role in adipocyte differentiation in vitro through interacting with PTPRD and thereby activating SFKs such as FYN tyrosine kinase.

Chordin Like-1 Regulates Osteoblast and Adipocyte Differentiation Through Stabilizing Insulin-Like Growth Factor Binding Protein 3.

Chordin like-1 (CHRDL1) is an antagonist of bone morphogenetic proteins (BMPs) that acts through binding BMPs and blocking their interaction with BMP receptors. CHRDL1 plays a role in osteoblast differentiation but controversial effects were reported. On the other hand, the role of CHRDL1 in adipogenesis is unknown. In the present study, we investigated the function of CHRDL1 in regulating differentiation of osteoblasts and adipocytes and elucidated the underlying mechanism. CHRDL1 expression was downregulated during osteogenesis while it was upregulated during adipogenesis in primary cultured and established mesenchymal progenitor cell lines. Functional experiments revealed that CHRDL1 suppressed osteoblast differentiation and promoted adipocyte differentiation. Mechanistic explorations revealed that CHRDL1 is directly bound to insulin-like growth factor binding protein 3 (IGFBP3) and attenuated the degradation of the latter. Furthermore, CHRDL1 and IGFBP3 suppressed the activity of insulin receptor substrate 1 (IRS1)/AKT serine/threonine kinase (AKT)/mechanistic target of rapamycin kinase complex 1 (mTORC1) signaling in progenitor cells undergoing osteogenic differentiation. By contrast, they activated AKT/mTORC1 signaling independently of IRS1 during adipogenic differentiation. CHRDL1 enhanced the interaction of nuclear IGFBP3 and retinoid X receptor α (RXRα) during adipogenesis, and inhibition of RXR inactivated AKT and attenuated the stimulation of adipogenic differentiation by CHRDL1. Overexpression of IGFBP3 relieved the perturbation of osteogenic and adipogenic differentiation of progenitor cells induced by CHRDL1 silencing. Finally, CHRDL1 and IGFBP3 were upregulated in the trabecular bone of aged mice. Our study provides evidence that CHRDL1 reciprocally regulates osteoblast and adipocyte differentiation through stabilizing IGFBP3 and differentially modulating AKT/mTORC1 signaling.

N-myc downstream regulated gene 1 suppresses osteoblast differentiation through inactivating Wnt/ß-catenin signaling.

BACKGROUND: N-myc downstream regulated gene 1 (NDRG1) plays a role in a variety of biological processes including differentiation of osteoclasts. However, it is not known if and how NDRG1 regulates osteogenic differentiation of marrow stromal progenitor cells. METHODS: Gene expression profiling analysis was performed to study the expression level of Ndrg1 during osteogenic and adipogenic differentiation. Gain-of-function and/or loss-of function experiments were carried out to study the role of NDRG1 in the proliferation and differentiation of marrow stromal progenitor cells and the mechanism underlying the function was investigated. Finally, in vivo transfection of Ndrg1 siRNA was done and its effect on osteogenic and adipogenic differentiation in mice was explored. RESULTS: Gene expression profiling analysis revealed that NDRG1 level was regulated during osteogenic and adipogenic differentiation of progenitor cells. The functional experiments demonstrated that NDRG1 negatively regulated the cell growth, and reciprocally modulated the osteogenic and adipogenic commitment of marrow stromal progenitor cells, driving the cells to differentiate toward adipocytes at the expense of osteoblast differentiation. Moreover, NDRG1 interacted with low-density lipoprotein receptor-related protein 6 (LRP6) in the stromal progenitor cells and inactivated the canonical Wnt/ß-catenin signaling cascade. Furthermore, the impaired differentiation of progenitor cells induced by Ndrg1 siRNA could be attenuated when ß-catenin was simultaneously silenced. Finally, in vivo transfection of Ndrg1 siRNA to the marrow of mice prevented the inactivation of canonical Wnt signaling in the BMSCs of ovariectomized mice, and ameliorated the reduction of osteoblasts on the trabeculae and increase of fat accumulation in the marrow observed in the ovariectomized mice. CONCLUSION: This study has provided evidences that NDRG1 plays a role in reciprocally modulating osteogenic and adipogenic commitment of marrow stromal progenitor cells through inactivating canonical Wnt signaling.

Metastasis suppressor 1 controls osteoblast differentiation and bone homeostasis through regulating Src-Wnt/ß-catenin signaling.

Metastasis suppressor 1 (MTSS1) plays an inhibitory role in tumorigenesis and metastasis of a variety of cancers. To date, the function of MTSS1 in the differentiation of marrow stromal progenitor cells remains to be explored. In the current study, we investigated whether and how MTSS1 has a role in osteoblast differentiation and bone homeostasis. Our data showed that MTSS1 mRNA was upregulated during osteoblast differentiation and downregulated in the osteoblastic lineage cells of ovariectomized and aged mice. Functional studies revealed that MTSS1 promoted the osteogenic differentiation from marrow stromal progenitor cells. Mechanistic explorations uncovered that the inactivation of Src and afterward activation of canonical Wnt signaling were involved in osteoblast differentiation induced by MTSS1. The enhanced osteogenic differentiation induced by MTSS1 overexpression was attenuated when Src was simultaneously overexpressed, and conversely, the inhibition of osteogenic differentiation by MTSS1 siRNA was rescued when the Src inhibitor was supplemented to the culture. Finally, the in vivo transfection of MTSS1 siRNA to the marrow of mice significantly reduced the trabecular bone mass, along with the reduction of trabecular osteoblasts, the accumulation of marrow adipocytes, and the increase of phospho-Src-positive cells on the trabeculae. No change in the number of osteoclasts was observed. This study has unraveled that MTSS1 contributes to osteoblast differentiation and bone homeostasis through regulating Src-Wnt/ß-catenin signaling. It also suggests the potential of MTSS1 as a new target for the treatment of osteoporosis.

Size-dependent transgenerational toxicity induced by nanoplastics in nematode Caenorhabditis elegans.

Nanoplastic exposure can potentially cause the severe transgenerational toxicity in organisms. However, the transgenerational nanoplastic toxicity and the underlying mechanisms are still largely unclear. Using Caenorhabditis elegans as an animal model, we here compared the transgenerational toxicity of two sizes of polystyrene nanoparticles (PS-NPs, 20 and 100 nm). The nematodes were exposed to PS-NPs at the P0 generation, and from the F1 generation the nematodes were grown under the normal condition. Exposure to 20 nm PS-NPs resulted in more severe transgenerational toxicity than exposure to 100 nm PS-NPs. At the concentration of 100 µg/L, the toxicity of 20 nm PS-NPs on locomotion and reproduction was detected at the F1-F6 generations, whereas the toxicity of 100 nm PS-NPs could only be observed at the F1-F3 generations. The difference in transgeneration toxicity between PS-NPs (20 nm) and PS-NPs (100 nm) was associated with the difference in transgenerational activation of oxidative stress. Based on observations on SOD-3::GFP, HSP-6::GFP, and HSP-4::GFP expressions, PS-NPs (20 nm) and PS-NPs (100 nm) further induced different transgenerational responses of anti-oxidation, mt UPR, and ER UPR. Our data suggested that the induction of transgenerational toxicity of PS-NPs was size dependent in nematodes. The results are helpful for our understanding the cellular mechanisms for the induction of transgenerational nanoplastic toxicity in organisms.

Acetylation regulation associated with the induction of protective response to polystyrene nanoparticles in Caenorhabditis elegans.

Caenorhabditis elegans is a useful animal model to assess nanoplastic toxicity. Using polystyrene nanoparticles (PS-NPs) as the example of nanoplastics, we found that exposure to PS-NPs (1-100 µg/L) from L1-larvae for 6.5 days increased expression of cbp-1 encoding an acetyltransferase. The susceptibility to PS-NPs toxicity was observed in cbp-1(RNAi) worms, suggesting that CBP-1-mediated histone acetylation regulation reflects a protective response to PS-NPs. The functions of CBP-1 in intestine, neurons, and germline were required for formation of this protective response. In intestinal cells, CBP-1 controlled PS-NPs toxicity by modulating functions of insulin and p38 MAPK signaling pathways. In neuronal cells, CBP-1 controlled PS-NPs toxicity by affecting functions of DAF-7/TGF-ß and JNK MAPK signaling pathways. In germline cells, CBP-1 controlled PS-NPs toxicity by suppressing NHL-2 activity, and NHL-2 further regulated PS-NPs toxicity by modulating insulin communication between germline and intestine. Therefore, our data suggested that the CBP-1-mediated histone acetylation regulation in certain tissues is associated with the induction of protective response to PS-NPs in C. elegans.

Notch receptor GLP-1 regulates toxicity of simulated microgravity stress by activating germline-intestine communication of insulin signaling in C. elegans.

We here investigated molecular basis of notch receptor GLP-1 in controlling simulated microgravity stress in Caenorhabditis elegans. glp-1 expression was decreased by simulated microgravity. Meanwhile, glp-1 mutation caused resistance to toxicity of simulated microgravity. GLP-1 acted in germline cells to control toxicity of simulated microgravity. In germline cells, RNAi knockdown of glp-1 increased daf-16 expression. RNAi knockdown of daf-16 suppressed resistance to toxicity of simulated microgravity in glp-1 mutant. In simulated microgravity treated worms, germline RNAi knockdown of glp-1 decreased expressions of daf-28, ins-39, and ins-8 encoding insulin peptides, and resistance to simulated microgravity toxicity could be detected in daf-28(RNAi), ins-39(RNAi), and ins-8(RNAi) worms. In simulated microgravity treated worms, RNAi knockdown of daf-28, ins-39, or ins-8 in germline cells further increased expression and nucleus localization of transcriptional factor DAF-16 in intestinal cells. Therefore, the GLP-1-activated germline-intestine communication of insulin signaling is required for control of simulated microgravity toxicity in C. elegans.

A novel Sprouty4-ERK1/2-Wnt/ß-catenin regulatory loop in marrow stromal progenitor cells controls osteogenic and adipogenic differentiation.

BACKGROUND: Sprouty (SPRY) proteins play critical roles in controlling cell proliferation, differentiation, and survival by inhibiting receptor tyrosine kinase (RTK)-mediated extracellular signal-regulated kinase (ERK) signaling. Recent studies have demonstrated that SPRY4 negatively regulates angiogenesis and tumor growth. However, whether SPRY4 regulates osteogenic and/or adipogenic differentiation of mesenchymal stem cells remains to be explored. RESULTS: In this study, we investigated the expression pattern of Spry4 and found that its expression was regulated during the differentiation of mouse marrow stromal progenitor cells and increased in the metaphysis of ovariectomized mice. In vitro loss-of-function and gain-of-function studies demonstrated that SPRY4 inhibited osteogenic differentiation and stimulated adipogenic differentiation of progenitor cells. In vivo experiments showed that silencing of Spry4 in the marrow of C57BL/6 mice blocked fat accumulation and promoted osteoblast differentiation in ovariectomized mice. Mechanistic investigations revealed the inhibitory effect of SPRY4 on canonical wingless-type MMTV integration site (Wnt) signaling and ERK pathway. ERK1/2 was shown to interact with low-density lipoprotein receptor-related protein 6 (LRP6) and activate the canonical Wnt signaling pathway. Inactivation of Wnt signaling attenuated the inhibition of adipogenic differentiation and stimulation of osteogenic differentiation by Spry4 small interfering RNA (siRNA). Finally, promoter study revealed that ß-catenin transcriptionally inhibited the expression of Spry4. CONCLUSIONS: Our study for the first time suggests that a novel SPRY4-ERK1/2-Wnt/ß-catenin regulatory loop exists in marrow stromal progenitor cells and plays a key role in cell fate determination. It also highlights the potential of SPRY4 as a novel therapeutic target for the treatment of metabolic bone disorders such as osteoporosis.

Lysophosphatidic acid receptor 4 regulates osteogenic and adipogenic differentiation of progenitor cells via inactivation of RhoA/ROCK1/ß-catenin signaling.

Recent evidence revealed that lysophosphatidic acid receptor 4 (LPAR4) plays a role in osteogenesis and bone remodeling in mice. However, the molecular mechanism by which LPAR4 controls osteogenic and adipogenic differentiation of mesenchymal progenitor cells remains pending. In the current study, our data showed that Lpar4 was expressed in bone and adipose tissue and the expression increased during osteoblast and adipocyte differentiation. Lpar4 overexpression in stromal ST2 and preosteoblastic MC3T3-E1 cells inhibited osteogenic differentiation. By contrast, Lpar4 overexpression in ST2 and mesenchymal C3H10T1/2 cells enhanced adipogenic differentiation. Conversely, depletion of endogenous Lpar4 in the progenitor cells induced osteogenic differentiation and inhibited adipogenic differentiation. Furthermore, enhanced osteoblast differentiation and alleviated fat accumulation were observed in marrow of mice after in vivo transfection of Lpar4 siRNA. Mechanism investigations revealed that LPAR4 inhibited the activation of ras homolog family member A (RhoA)/Rho-associated kinases 1 (ROCK1) and canonical Wnt signal pathways. ROCK1 was shown to be able to activate Wnt/ß-catenin pathway. We further demonstrated that the overexpression of ROCK1 stimulated osteogenic differentiation and restrained adipogenic differentiation from stromal progenitor cells. Moreover, overexpression of ROCK1 attenuated the inhibition of osteogenic differentiation by LPAR4. The current study has provided evidences demonstrating that RhoA/ROCK1 activates ß-catenin signaling to promote osteogenic differentiation and conversely restrain adipogenic differentiation. The inactivation of RhoA/ROCK1/ß-catenin signaling is involved in LPAR4 regulation of the directional differentiation of marrow stromal progenitor cells.

A novel long noncoding RNA PGC1ß-OT1 regulates adipocyte and osteoblast differentiation through antagonizing miR-148a-3p.

Long noncoding RNAs (LncRNAs) have been implicated in the regulation of adipocyte and osteoblast differentiation. However, the functional contributions of LncRNAs to adipocyte or osteoblast differentiation remain largely unexplored. In the current study we have identified a novel LncRNA named peroxisome proliferator-activated receptor γ coactivator-1ß-OT1 (PGC1ß-OT1). The expression levels of PGC1ß-OT1 were altered during adipogenic and osteogenic differentiation from progenitor cells. 5'- and 3'-rapid amplification of cDNA ends (RACE) revealed that PGC1ß-OT1 is 1759 nt in full length. Overexpression of PGC1ß-OT1 in progenitor cells inhibited adipogenic differentiation, whereas silencing of endogenous PGC1ß-OT1 induced adipogenic differentiation. By contrast, overexpression of PGC1ß-OT1 in progenitor cells stimulated, whereas silencing of PGC1ß-OT1 inhibited osteogenic differentiation. In vivo experiment showed that silencing of endogenous PGC1ß-OT1 in marrow stimulated fat accumulation and decreased osteoblast differentiation in mice. Mechanism investigations revealed that PGC1ß-OT1 contains a functional miR-148a-3p binding site. Overexpression of the mutant PGC1ß-OT1 with mutation at the binding site failed to regulate either adipogenic or osteogenic differentiation. In vivo crosslinking combined with affinity purification studies demonstrated that PGC1ß-OT1 physically associated with miR-148a-3p through the functional miR-148a-3p binding site. Furthermore, PGC1ß-OT1 affected the expression of endogenous miR-148a-3p and its target gene lysine-specific demethylase 6b (KDM6B). Supplementation of miR-148a-3p in progenitor cells blocked the inhibitory effect of PGC1ß-OT1 on adipocyte formation. Moreover, overexpression of Kdm6b restored the osteoblast differentiation which was inhibited by silencing of endogenous PGC1ß-OT. Our studies provide evidences that the novel LncRNA PGC1ß-OT1 reciprocally regulates adipogenic and osteogenic differentiation through antagonizing miR-148a-3p and enhancing KDM6B effect.

Deep hypothermic preservation of autologous skin in the treatment of large-area circumferential multi-plane degloving trauma: a pilot study of 2 cases.

To evaluate the clinical outcome of deep hypothermic preservation of autologous skin in the treatment of large-area skin avulsion. Medium or full thickness-skin slices were harvested from large avulsion flaps between July and November 2017. They were stored in liquid nitrogen by vitrification. After the patient's condition became stable and the growth of the wound granulation tissue was satisfactory, the frozen skin slices were reheated quickly and replanted to the wound. Autologous skin that had been kept by deep cryopreservation had a high survival rate when grafted. It did not create new trauma or bring additional pain to patients. Yet it could shorten the course of treatment and reduce the medical cost for patients. It is an effective and economical way to treat large-area skin avulsion.

Fasciocutaneous flap with perforating branches of peroneal artery repairing soft tissue loss in anterior and middle parts of children's feet: A STROBE-compliant article.

Repairing soft tissue loss in feet's anterior and middle parts has become a problem, especially for children. We observed the feasibility and clinical effects of superficial peroneal fasciocutaneous flap pedicled with terminal perforating branches of peroneal artery for repairing children's feet.Between January 2015 and December 2016, soft tissue loss in anterior and middle regions of feet were repaired using superficial peroneal fasciocutaneous flap pedicled with terminal perforating branches of peroneal artery in 8 children with a median age of 6.5 [4-9, interquartile range (IQR) = 3] years. The skin of lower leg was intact, and the soft tissue loss area was located in the anterior and middle regions of feet with a size of 5 cm × 4 cm to 11 cm × 7 cm combined with the exposure of tendons and joints in all the 8 children. On the basis of the conditions above, there were no indications of free skin grafting. Foot wounds were repaired all with the superficial peroneal fasciocutaneous flap pedicled with terminal perforating branches of peroneal artery (6 cm × 5 cm to 12 cm × 8 cm), and then the donor area was sutured to narrow the donor area followed by intermediate split thickness skin graft. The perforating branch trunk of peroneal artery was used as a rotation point (4 cm above the lateral malleolus) in 5 children and descending branch of perforating branch of peroneal artery as a rotation point (2 cm under the lateral malleolus) in 3 children.All flaps survived with primary healing in the 8 children. Postoperative median 7.5-month (3-12, IQR = 4.5) follow-up indicated that flap color and texture were fine, the appearances of donor and recipient areas were satisfactory, wearing shoes was not affected, and walking function and foot blood circulation were normal.For intractable soft tissue loss in the anterior and middle regions of children's feet, superficial peroneal fasciocutaneous flap pedicled with terminal perforating branches of peroneal artery can improve recipient area appearance and walking function because it has the characteristics of reliable blood supply and convenient rotation. It is worth using this method widely in clinics.

miR-148a-3p regulates adipocyte and osteoblast differentiation by targeting lysine-specific demethylase 6b.

Recent emerging studies of miRNAs in mesenchymal stem cell commitment toward adipocyte and osteoblast provide new insights for the understanding of the molecular basis of adipogenesis and osteogenesis. The current study revealed that miR-148a-3p was altered in primary cultured marrow stromal cells and established stromal ST2 line after adipogenic and/or osteogenic treatment. Supplementing miR-148a-3p activity inhibited cell growth and induced ST2 to differentiate into mature adipocytes. Conversely, inactivation of the endogenous miR-148a-3p suppressed ST2 to fully differentiate. By contrast, supplementation of the miR-148a-3p blunted osteoblast differentiation. Lysine-specific demethylase 6b (Kdm6b), a recently identified regulator of osteoblast differentiation was shown to be a direct target of miR-148a-3p by using the luciferase assay. Overexpression of Kdm6b attenuated miR-148a-3p stimulation of adipogenic differentiation. Taken together, our study provides evidences that miR-148a-3p reciprocally regulates adipocyte and osteoblast differentiation through directly targeting Kdm6b.

miR-337 can be a key negative regulator in melanoma.

Incidence of melanoma is increasing annually worldwide. There remains a lack of suitable treatment methods which can significantly improve the 5-year survival rates of patients. It is established that micro RNAs (miRNAs) have important roles in the diagnosis and treatment of cancer. MiR-337 had been reported to regulate the development of variety of cancers, as a cancer suppressive factor. In our research we found that miR-337 had a lower expression in melanoma than adjacent tissues. The patients who had a lower miR-337 also got a worse survival. MiR-337 could target STAT3 to regulate the occurrence and development of melanoma.  In summary, our findings suggest that the miR-337/STAT3 axis may serve as a potential target for the treatment of melanoma.

Identification and function analysis of contrary genes in Dupuytren's contracture.

The present study aimed to analyze the expression of genes involved in Dupuytren's contracture (DC), using bioinformatic methods. The profile of GSE21221 was downloaded from the gene expression ominibus, which included six samples, derived from fibroblasts and six healthy control samples, derived from carpal-tunnel fibroblasts. A Distributed Intrusion Detection System was used in order to identify differentially expressed genes. The term contrary genes is proposed. Contrary genes were the genes that exhibited opposite expression patterns in the positive and negative groups, and likely exhibited opposite functions. These were identified using Coexpress software. Gene ontology (GO) function analysis was conducted for the contrary genes. A network of GO terms was constructed using the reduce and visualize gene ontology database. Significantly expressed genes (801) and contrary genes (98) were screened. A significant association was observed between Chitinase-3-like protein 1 and ten genes in the positive gene set. Positive regulation of transcription and the activation of nuclear factor-κB (NF-κB)-inducing kinase activity exhibited the highest degree values in the network of GO terms. In the present study, the expression of genes involved in the development of DC was analyzed, and the concept of contrary genes proposed. The genes identified in the present study are involved in the positive regulation of transcription and activation of NF-κB-inducing kinase activity. The contrary genes and GO terms identified in the present study may potentially be used for DC diagnosis and treatment.

The neuroprotective mechanism of puerarin in the treatment of acute spinal ischemia-reperfusion injury is linked to cyclin-dependent kinase 5.

Puerarin is shown to exert a variety of pharmacological effects including neuroprotective properties. However, mechanisms of the action are not fully understood. This study was designed to explore the mechanism of puerarin in treatment of acute spinal ischemia-reperfusion injury in rats. Acute spinal ischemia-reperfusion injury was conducted by aortic occlusion in twenty-eight male Sprague-Dawley rats, weighting 230-250 g. The animals were randomly divided into four groups. In the animals with puerarin treatment, 50 mg/kg of puerarin was injected intraperitoneally after reperfusion, and followed by the same dose of injection every 24h for 2 days. In the animals with roscovitine pre-treatment, 30 mg/kg roscovitine was intravenously administrated 60 min before spinal ischemia started. After spinal ischemia for 60 min followed by 48 h of reperfusion, the motor function, spinal infarction volume, apoptosis indices and the activities of Cdk5 and p25 were examined. Acute spinal ischemia-reperfusion resulted in an injury of the spines associated with motor deficit, elevation of Cdk5 and p25 activities, and increase in the spinal apoptosis number and spinal infarction volume. Puerarin improved motor function associated with the decreased apoptosis number, spinal infarction volume, and Cdk5 and p25 activities. The present study indicated that reduction of spinal injury was associated with inhibition of Cdk5 and p25, and that inhibition of Cdk5 and p25 was one of the neuroprotective mechanisms in the puerarin treatment of acute ischemia/reperfusion-induced spinal injury in rats.

Venous arterialization for the treatment of large-area foot skin retrograde avulsion.

Between 2009 and 2011, three patients with large-area foot skin retrograde avulsion (more than 1% of the body surface area) underwent venous arterialization. Anastomosis of the artery in the wound surface with the vein in the skin flap and an appropriate number of venous end-to-end anastomoses were performed. The skin flaps survived in all 3 patients. Six months postoperatively, the flap elasticity and appearance were close to that of normal skin, and foot function was better without scar contracture. When venous arterialization is used to treat foot avulsion, the following points should be noted. Surgical indications include no fresh bleeding from the wound edge of the avulsed skin after debridement, more complete avulsed skin, and superficial veins that do not completely separate from the avulsed skin. Venous arterialization is not suitable to avulsion with fresh bleeding, avulsed skin in small fragments, and avulsion with a subcutaneous venous network embolism. During debridement, the subcutaneous venous network should be protected to avoid exposing the vein stems outside the fat layer. If the avulsion is less than 1% of the body surface area, arterial-venous anastomosis can provide adequate blood supply. Venous-venous anastomosis is performed as much as possible to enhance venous return and decrease microcirculatory pressure, which is conducive to the establishment of effective blood circulation.