Cytotoxic Compounds from Belamcanda chinensis (L.) DC Induced Apoptosis in Triple-Negative Breast Cancer Cells.

Four compounds (1, 5, 7, and 8) were first isolated from the genus Belamcanda Adans. nom. conserv., and six known compounds (2-4, 6, 9, and 10) were isolated from the rhizome of Belamcanda chinensis (L.) DC. Their structures were confirmed by spectroscopic data. Herein, compounds 1-10 were rhapontigenin, trans-resveratrol, 5,7,4'-trihydroxy-6,3',5'-trimethoxy-isoflavone, irisflorentin, 6-hydroxybiochannin A, iridin S, pinoresinol, 31-norsysloartanol, isoiridogermanal, and iristectorene B, respectively. All compounds were evaluated for their antiproliferative effects against five tumor cell lines (BT549, 4T1, MCF7, MDA-MB-231, and MDA-MB-468). Among them, compound 9 (an iridal-type triterpenoid) showed the highest activity against 4T1 and MDA-MB-468 cells. Further studies displayed that compound 9 inhibited cell metastasis, induced cells cycle arrest in the G1 phase, exhibited significant mitochondrial damage in 4T1 and MDA-MB-468 cells including excess reactive oxygen species, decreased mitochondrial membrane potential, and induced 4T1 and MDA-MB-468 cell apoptosis for the first time. In summary, these findings demonstrate that compound 9 exerts promising potential for triple-negative breast cancer treatment and deserves further evaluation.

Graphene-modified CePO4 nanorods effectively treat breast cancer-induced bone metastases and regulate macrophage polarization to improve osteo-inductive ability.

BACKGROUND: Breast cancer bone metastasis has become one of the most common complications; however, it may cause cancer recurrence and bone nonunion, as well as local bone defects. METHODS: Herein, In vitro, we verified the effect of bioscaffold materials on cell proliferation and apoptosis through a CCK8 trial, staining of live/dead cells, and flow cytometry. We used immunofluorescence technology and flow cytometry to verify whether bioscaffold materials regulate macrophage polarization, and we used ALP staining, alizarin red staining and PCR to verify whether bioscaffold material promotes bone regeneration. In vivo, we once again studied the effect of bioscaffold materials on tumors by measuring tumor volume in mice, Tunel staining, and caspase-3 immunofluorescence. We also constructed a mouse skull ultimate defect model to verify the effect on bone regeneration. RESULTS: Graphene oxide (GO) nanoparticles, hydrated CePO4 nanorods and bioactive chitosan (CS) are combined to form a bioactive multifunctional CePO4/CS/GO scaffold, with characteristics such as photothermal therapy to kill tumors, macrophage polarization to promote blood vessel formation, and induction of bone formation. CePO4/CS/GO scaffold activates the caspase-3 proteasein local tumor cells, thereby lysing the DNA between nucleosomes and causing apoptosis. On the one hand, the as-released Ce3+ ions promote M2 polarization of macrophages, which secretes vascular endothelial growth factor (VEGF) and Arginase-1 (Arg-1), which promotes angiogenesis. On the other hand, the as-released Ce3+ ions also activated the BMP-2/Smad signaling pathway which facilitated bone tissue regeneration. CONCLUSION: The multifunctional CePO4/CS/GO scaffolds may become a promising platform for therapy of breast cancer bone metastases.

Effect mechanism of copper ions on photocatalytic activity of TiO2/graphene oxide composites for phenol-4-sulfonic acid photodegradation.

Organic pollutants in electroplating wastewater can be removed by photodegradation, however the effect mechanism of heavy metal ions on photocatalytic activity still remains unknown. Herein, we firstly reported the self-assembly synthesis of titanium dioxide/reduced graphene oxide (TiO2/rGO) composites for phenol-4-sulfonic acid (PSA) removal, and investigated the effects of Cu2+ ions on photocatalytic efficiency. During the self-assemble process, rGO nanosheets were connected together to form network macropores, and simultaneously induced the deposition of hierarchically nanostructured TiO2 microspheres. The synergetic effects of TiO2 microspheres and rGO nanosheets improved the photocatalytic activity by enhancing light adsorption ability, stabilizing electron-hole separation and decreasing band gap energy. The Cu2+ ions in wastewater showed positive and negative effects on PSA photodegradation. In the photocatalytic reaction, the electron-induced reduction reaction of Cu(II) into Cu(0) or Cu(I) took place, which inhibited electron-hole recombination and thus enhanced photocatalytic activity. However, the high chemical stability of PSA-Cu(II) complex compounds held back PSA photodegradation. The appropriate concentrations of Cu2+ ions at around 25 mg/L accelerated PSA photodegradation over TiO2/rGO composites. The PSA degradation into CO2 and H2O was performed by using hydroquinone, benzoquinone and maleic acid as degradation intermediates. Hence, TiO2/rGO composites are novel multifunctional photocatalysts to purify electroplating wastewater.

Effect of carboplatin injection on Bcl-2 protein expression and apoptosis induction in Raji cells.

To investigate the effects of carboplatin (CBP) injection on apoptosis induction in the human lymphoma cell line Raji and to explore the underlying mechanism, Raji cells were randomly divided into two treatment groups. Cells in the experimental groups were treated with 15 µM CBP injection, those in the control groups were treated with solvent, and both groups were treated for 24, 48 and 72 h. Cells from each group were collected for subsequent assays. For each group, the relative expression of B-cell lymphoma-2 (Bcl-2) was determined by Western blot (WB), the expression pattern of Bcl-2 was observed by immunocytochemistry (ICC), and cell apoptosis was observed after Hoechst 33342 staining. Real-time PCR detection of the relative expression levels of the Bax and caspase-3 genes in each group of cells were performed. The WB results showed that the relative expression of the Bcl-2 protein significantly decreased 48 and 72 h after treatment in the CBP groups compared with the control groups (P<0.001), and a significant decrease in the expression of this protein was also noted at 48 h vs 24 h, 72 h vs 48 h, and 72 h vs 24 h with extremely significant differences (P<0.001). Moreover, the expression of the Bcl-2 protein decreased as the duration of CBP treatment increased, showing a time-dependent manner. The ICC results were consistent with the WB findings. The expression of the Bcl-2 protein in the CBP treatment group was significantly reduced 48 h and 72 h after treatment compared with the control group (P<0.001). A time-dependent manner was also noted in the expression of this protein, i.e., the expression level decreased gradually at 24, 48, and 72 h after treatment with statistically significant differences (P<0.001). Hoechst 33342 staining showed that the apoptosis rates at the three time points in the treatment groups were significantly higher than those in the control groups (P<0.001), and a time-effect relationship was observed. The apoptosis rate increased over time with a significant difference (P<0.05). The PCR results showed that the Bax and caspase-3 gene expression trend was the same but opposite that of Bcl-2. After treatment for 24 h and 48 h, the gene expression of the medication groups decreased with a very significant difference (P<0.001), and with prolonged action time, the relative expression of the genes in the medication groups showed an upward trend. Comparing 48 h with 72 h and 24 h with 72 h, the gene expression levels also increased, reaching a very significant difference (P<0.001), and there was a certain time dependence. CBP injection significantly reduced the expression of the Bcl-2 protein and induced apoptosis of Raji cells in a time-dependent manner. Moreover, CBP injection can increase the expression levels of the Bax and caspase-3 genes.

Sphingobium algorifonticola sp. nov., isolated from a cold spring.

Strain TLA-22T, isolated from a cold spring in Taiwan, was characterized using a polyphasic taxonomy approach. Cells were Gram-stain-negative, aerobic, poly-ß-hydroxybutyrate-accumulating, motile by means of a single polar flagellum, rod-shaped and formed bright yellow colonies. Optimal growth occurred at 20-25 °C, pH 6-6.5, and in the presence of 0.5 % NaCl. The major fatty acids of TLA-22T were C18 : 1 ω7 c and C17 : 1ω6c. The predominant hydroxy fatty acids were C15 : 0 2-OH and C14 : 0 2-OH. The polar lipid profile consisted of a mixture of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidyldimethylethanolamine, sphingoglycolipid, an unidentified aminophospholipid, an unidentified phospholipid and three unidentified lipids. TLA-22T contained spermidine as the major polyamine and putrescine as the minor component. The only isoprenoid quinone was Q-10. The genomic DNA G+C content of TLA-22T was 63.2 mol%. Phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of 92 protein clusters indicated that TLA-22T was a mem,ber of a phylogenetic lineage including members of the genus Sphingobium. TLA-22T was most closely related to Sphingobium aromaticiconvertens RW16T, with a 97.4 % 16S rRNA gene sequence similarity. TLA-22T showed 74.8-75.7 % average nucleotide identity and 20.1-22.0 % digital DNA-DNA hybridization identity with the strains of other species of the genus Sphingobium. On the basis of phenotypic and genotypic properties and phylogenetic inference, strain TLA-22T should be classified as representing a novel species of the genus Sphingobium, for which the name Sphingobium algorifonticola sp. nov. is proposed. The type strain is TLA-22T (=BCRC 81097T =LMG 30309T=KCTC 62189T).

Sphingobium fluviale sp. nov., isolated from a river.

A Gram-stain-negative, rod-shaped, non-motile, poly-ß-hydroxybutyrate-accumulating and aerobic bacterial strain, designated CHR27T, was isolated and characterized by using the polyphasic taxonomy approach. The results of phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of an up-to-date bacterial core gene set (92 protein clusters) indicated that strain CHR27T is affiliated with species in the genus Sphingobium. 16S rRNA gene sequence similarity results indicated that strain CHR27T was closely related to species of the genus Sphingobium (94.3-97.0 %), and had the highest sequence similarity to Sphingobium qiguonii X23T (97.0 %). Strain CHR27T showed 19.4-22.1 % digital DNA-DNA hybridization values and 73.2-74.8 % average nucleotide identity values with the strains of other Sphingobium species. Optimal growth occurred at 25 °C, pH 7.5 and in the absence of NaCl. The major fatty acids of strain CHR27T were C18 : 1ω7c and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c). The predominant hydroxy fatty acid was C14 : 0 2-OH. The polar lipid profile consisted of a mixture of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidyldimethylethanolamine, two unidentified sphingoglycolipids and an unidentified aminophospholipid. Strain CHR27T contained spermidine as the major polyamine and putrescine as a minor component. The only isoprenoid quinone was ubiquinone-10. The genomic DNA G+C content of strain CHR27Twas 61.8 mol%. On the basis of the phylogenetic inference and phenotypic data, strain CHR27T was considered a representative of a novel species within the genus Sphingobium. The name Sphingobium fluviale sp. nov. is proposed, with strain CHR27T (=BCRC 81121T=LMG 30596T=KCTC 62510T) as the type strain.

Gadolinium-doped mesoporous calcium silicate/chitosan scaffolds enhanced bone regeneration ability.

Chitosan (CTS) and mesoporous calcium silicate (MCS) have been developed for bone defect healing; however, their bone regeneration capacity still does not satisfy the patients with bone diseases. Gadolinium (Gd) is accumulated in human bones, and plays a beneficial role in regulating cell performance and bone regeneration. We firstly constructed Gd-doped MCS/CTS (Gd-MCS/CTS) scaffolds by a lyophilization technology. The interconnected arrangement of CTS films lead to forming macropores by using ice crystals as templates during the lyophilization procedure, and the Gd-MCS nanoparticles dispersed uniformly on the macropore walls. The biocompatible chemical components and hierarchical pores facilitated the attachment and spreading of rat bone marrow-derived mesenchymal stem cells (rBMSCs). Interestingly, the Gd dopants in the scaffolds effectively activated the Wnt/ß-catenin signaling pathway, resulting in excellent cell proliferation and osteogenic differentiation capacities. The osteogenic-related genes such as alkaline phosphatase (ALP), runt-related transcription factor 2 (Runx2) and collagen type1 (COL-1) were remarkably up-regulated by Gd-MCS scaffolds as compared with MCS scaffolds, and their expression levels increased in a positive correlation with Gd doping amounts. Moreover, in vivo rat cranial defect tests further confirmed that Gd-MCS/CTS scaffolds significantly stimulated collagen deposition and new bone formation. The exciting finding suggested the beneficial effects of Gd3+ ions on osteogenic differentiation and new bone regeneration, and Gd-MCS/CTS scaffolds can be employed as a novel platform for bone defect healing.

Amniculibacterium aquaticum gen. nov., sp. nov., a new member of the family Flavobacteriaceae isolated from a stream.

Strain KYPW7T, isolated from the Funglin Stream in Taiwan, was characterized using a polyphasic taxonomy approach. Cells of strain KYPW7T were Gram-stain-negative, aerobic, non-spore forming, non-motile rods and formed white colonies. Growth occurred at 15-30 °C (optimum 25 °C), at pH 6-8 (optimum pH 6.5) and with 0-1% NaCl (optimum 0%). Phylogenetic analyses based on 16S rRNA and coding sequences of 92 protein clusters showed that strain KYPW7T represents a novel genus in the family Flavobacteriaceae. The 16S rRNA gene sequence of strain KYPW7T was related to the species of the genera Chryseobacterium (91.8-96.0% sequence similarity), Bergeyella (95.1-95.8%), Cloacibacterium (94.5-95.7%), Daejeonia (95.6%) and Riemerella (94.0-95.0%). Strain KYPW7T showed less than 72% average nucleotide identity and less than 24% digital DNA-DNA hybridization identity compared to the type strains of related genera within the family Flavobacteriaceae. The predominant fatty acids were iso-C15:0 and iso-C17:0 3-OH. The major isoprenoid quinone was MK-6 and the DNA G + C content was 36.8 mol%. The polar lipids had phosphatidylethanolamine, three uncharacterized aminophospholipids and an uncharacterized phospholipid. The polyamines contained homospermidine, putrescine and spermidine. On the basis of the genotypic and phenotypic data, strain KYPW7T represents a novel species of a new genus in the family Flavobacteriaceae, for which the name Amniculibacterium aquaticum gen. nov., sp. nov. is proposed. The type strain is KYPW7T (= BCRC 81123T = LMG 30598T = KCTC 62512T).

Flavobacterium amnicola sp. nov., isolated from a sub-tropical stream.

Strain LLJ-11T, isolated from water sampled from a freshwater stream in Taiwan, was characterized using a polyphasic taxonomy approach. Cells of strain LLJ-11T were Gram-stain-negative, strictly aerobic, motile by gliding, rod-shaped and formed translucent yellow colonies. Optimal growth occurred at 25 °C, pH 7 and 0 % NaCl. Phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of 92 protein clusters indicated that strain LLJ-11T is affiliated with species in the genus Flavobacterium. Strain LLJ-11T was most closely related to Flavobacterium amniphilum KYPY10T with 98.0 % 16S rRNA gene sequence identity. The DNA-DNA relatedness of strain LLJ-11T with respect to Flavobacterium species was less than 35 %. Average nucleotide identity and digital DNA-DNA hybridization values between strain LLJ-11T and the type strains of other closely related Flavobacterium species were 70.0-76.3 % and 21.1-23.9 %, respectively. Strain LLJ-11T contained iso-C15 : 0, iso-C15 : 1 G, iso-C17 : 0 3-OH, iso-C15 : 0 3-OH, summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c) and summed feature 9 (iso-C17 : 1ω9c and/or 10-methyl C16 : 0) as the predominant fatty acids. The major isoprenoid quinone was MK-6. The polar lipid profile consisted of phosphatidylethanolamine, three uncharacterized aminophospholipids and two uncharacterized phospholipids. The major polyamine was homospermidine. The DNA G+C content was 34.8 mol%. On the basis of the phylogenetic inference and phenotypic data, strain LLJ-11T is considered a representative of a novel species within the genus Flavobacterium. The name Flavobacterium amnicola sp. nov. is proposed, with strain LLJ-11T (=BCRC 81124T=LMG 30599T=KCTC 62514T) as the type strain.

Gadolinium-doped bioglass scaffolds promote osteogenic differentiation of hBMSC via the Akt/GSK3ß pathway and facilitate bone repair in vivo.

BACKGROUND: Biomaterial-induced osteogenesis is mainly related to hierarchically porous structures and bioactive components. Rare earth elements are well known to promote osteogenesis and stimulate bone repair; however, the underlying biological effects of gadolinium (Gd) element on bone regeneration are not yet known. METHODS: In this study, we successfully fabricated gadolinium-doped bioglass (Gd-BG) scaffolds by combining hollow mesoporous Gd-BG microspheres with chitosan and evaluated in vitro effects and underlying mechanisms with Cell Counting Kit-8, scanning electron microscopy, alkaline phosphatase, Alizarin red staining, and polymerase chain reaction. Cranial defect model of rats was constructed to evaluate their in vivo effects. RESULTS: The results indicated that Gd-BG scaffolds could promote the proliferation and osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hBMSCs). Mechanistically, the Akt/GSK3ß signaling pathway was activated by the Gd-BG scaffolds. The enhancing effect of Gd-BG scaffolds on the osteogenic differentiation of hBMSCs was inhibited by the addition of LY294002, an inhibitor of Akt. Moreover, the in vivo cranial defect model of rats indicated that the Gd-BG scaffolds could effectively promote bone regeneration. CONCLUSION: Both in vitro and in vivo results suggested that Gd-BG scaffolds have promising applications in bone tissue engineering.

Incorporation of cerium oxide in hollow mesoporous bioglass scaffolds for enhanced bone regeneration by activating the ERK signaling pathway.

Hierarchically porous structures and bioactive compositions of artificial biomaterials play a positive role in bone defect healing and new bone regeneration. Herein, cerium oxide nanoparticles-modified bioglass (Ce-BG) scaffolds were firstly constructed by the incorporation of hollow mesoporous Ce-BG microspheres in CTS via a freeze-drying technology. The interconnected macropores in Ce-BG scaffolds facilitated the in-growth of bone cells/tissues from material surfaces into the interiors, while the hollow cores and mesopore shells in Ce-BG microspheres provides more active sites for bone mineralization. The cerium oxide nanoparticles in the scaffolds rapidly promoted the proliferation and osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hBMSCs), as confirmed by the up-regulation of osteogenesis-related markers such as OCN, ALP and COL-1. The enhanced osteoinductivity of Ce-BG scaffolds was mainly related to the activated ERK pathway, and it was blocked by adding a selective ERK1/2 inhibitor (SCH772984). In vivo rat cranial defect models revealed that Ce-BG scaffolds accelerated collagen deposition, osteoblast formation and bone regeneration as compared to BG scaffolds. The exciting results demonstrated that the synergistic effects between hierarchically porous structures and cerium oxide nanoparticles contributed to osteogenic ability, and hollow mesoporous Ce-BG scaffolds would be a novel platform for bone regeneration.

Ursolic acid loaded-mesoporous bioglass/chitosan porous scaffolds as drug delivery system for bone regeneration.

Bioglass scaffolds have great application potentials in orthopedics, and Ursolic acid (UA) can effectively promote in vivo new bone formation. Herein, we for the first time developed the mesoporous bioglass/chitosan porous scaffolds loaded with UA (MBG/CS/UA) for enhanced bone regeneration. The MBG microspheres with particle sizes of ~300 nm and pore sizes of ~3.9 nm were uniformly dispersed on the CS films. The mesoporous structure within the MBG microspheres and the hydrogen bonding between the scaffolds and UA drugs made the MBG/CS/UA scaffolds have controlled drug release performances. The as-released UA drugs from the scaffolds increased remarkably the alkaline phosphatase activity, osteogenic differentiation related gene type I collagen, runt-related transcription factor 2 expression, and osteoblast-associated protein expression. Moreover, the results of micro-CT images, histomorphological observations demonstrated that the MBG/CS/UA scaffolds improved new bone formation ability. Therefore, the MBG/CS/UA porous scaffolds can be used as novel bone tissue engineering materials.

pH-responsive mesoporous ZSM-5 zeolites/chitosan core-shell nanodisks loaded with doxorubicin against osteosarcoma.

Oral or intravenous chemotherapy is an important strategy to treat metastatic cancer, but it may cause systemic toxicity for healthy tissue. Herein, we for the first time fabricated mesoporous ZSM-5 zeolites/chitosan core-shell nanodisks loaded with doxorubicin (ZSM-5/CS/DOX) as drug delivery systems against osteosarcoma. The mesoporous ZSM-5 zeolites exhibited disk-like shapes with thicknesses of 100nm and diameters of 300nm, and the mesopores with pore sizes of 3.75nm were originated from desilication treatment. The pH-responsive ZSM-5/CS/DOX nanodisks possessed a great drug loading efficiency of 97.7%, and their controlled release trends of DOX were fitted well with the Korsmeyer-Peppas model. The DOX could be efficiently released the ZSM-5/CS/DOX nanodisks after cellular endocytosis and induced cancer cells apoptosis. Moreover, the pH-responsive drug carriers led to efficient tumor inhibition with low side effects, especially cardiac toxicity, as confirmed by pharmacokinetic study, serological examination and H&E staining assays. Therefore, the ZSM-5/CS/DOX nanodisks are a promising pH-responsive drug carrier for targeted cancer therapy.

Magnetic nanoparticles modified-porous scaffolds for bone regeneration and photothermal therapy against tumors.

For effectively treating tumor related-bone defects, design and fabrication of multifunctional biomaterials still remain a great challenge. Herein, we firstly fabricated magnetic SrFe12O19 nanoparticles modified-mesoporous bioglass (BG)/chitosan (CS) porous scaffold (MBCS) with excellent bone regeneration and antitumor function. The as-produced magnetic field from MBCS promoted the expression levels of osteogenic-related genes (OCN, COL1, Runx2 and ALP) and the new bone regeneration by activated BMP-2/Smad/Runx2 pathway. Moreover, the SrFe12O19 nanoparticles in MBCS improved the photothermal conversion property. Under the irradiation of near-infrared (NIR) laser, the elevated temperatures of tumors co-cultured with MBCS triggered tumor apoptosis and ablation. As compared with the pure scaffold group, MBCS/NIR group possessed the excellent antitumor efficacy against osteosarcoma via the hyperthermia ablation. Therefore, the multifunctional MBCS with excellent bone regeneration and photothermal therapy functions has a great application for treating the tumor-related bone defects.

Lanthanum-Doped Chitosan Hydrogels Promote the Apoptosis of Melanoma Cells by Bcl-2/Bax Pathway.

The surgical resection of melanoma may cause skin wounds, and the remaining melanoma cells bring a great risk of tumor recurrence. To overcome the above problem, we for the first time constructed lanthanum-doped chitosan (La-CS) hydrogels with excellent wound healing and antitumor functions. The La element was uniformly dispersed within whole hydrogels, and part of La3+ ions reacted with CS to form La-CS complex. The complexation interaction between La3+ ions and CS significantly improve the La3+ release performances of La-CS hydrogels. The as-released La3+ ions from the composite hydrogels selectively inhibited the proliferation of B-16 melanoma cells, but showed lower toxic side effects to L929 skin fibroblast cells. Moreover, the La3+ ions triggered the apoptosis of B-16 cells through Bcl-2/Bax pathway, as confirmed by the Annexin Vand PI double staining, flow cytometry, and Western blot results. The in vivo tumor models of C57 mice revealed that the La-CS hydrogels had more significant relapse-inhibition effects on B-16 melanoma cells than the pure CS hydrogels. At the same time, the in vivo wound healing was accelerated by the multifunctional hydrogels. The exciting finding provides a critical and promising strategy in the construction of La-doped hydrogels for oncotherapy.

Three new sesquiterpenes from Pterocarpus santalinus.

Three new sesquiterpenes of canusesnol K (1), canusesnol L (2) and 12, 15-dihydroxycurcumene (3), along with five known ones (4-8), were isolated from the heartwood extract of Pterocarpus santalinus. Their structures were established by extensive analyses of 1D and 2D NMR spectroscopy, including 1H NMR, 13C NMR, HSQC, HMBC and NOESY, and HRESI-MS. The absolute configurations of the new compounds were established with Modified Mosher's method. The cytotoxic activities of all these compounds against HepG2 (human liver cancer), MCF-7 (human breast cancer), MDA-MB-231 (human breast cancer), and Hela (human cervical carcinoma) cancer cell lines were evaluated. Compound 1 exhibited moderate cytotoxic activity toward MDA-MB-231 cell lines.

MgAl layered double hydroxide/chitosan porous scaffolds loaded with PFTα to promote bone regeneration.

Poor bone formation remains a key risk factor associated with acellular scaffolds that occurs in some bone defects, particularly in patients with metabolic bone disorders and local osteoporosis. We herein fabricated for the first time layered double hydroxide-chitosan porous scaffolds loaded with PFTα (LDH-CS-PFTα scaffolds) as therapeutic bone scaffolds for the controlled release of PFTα to enhance stem cell osteogenic differentiation and bone regeneration. The LDH-CS scaffolds had three-dimensional interconnected macropores, and plate-like LDH nanoparticles were uniformly dispersed within or on the CS films. The LDH-CS scaffolds exhibited appropriate PFTα drug delivery due to hydrogen bonding among LDH, CS and PFTα. In vitro functional studies demonstrated that the PFTα molecules exhibited potent ability to induce osteogenesis of hBMSCs via the GSK3ß/ß-catenin pathway, and the LDH-CS-PFTα scaffolds significantly enhanced the osteogenic differentiation of hBMSCs. In vivo studies revealed significantly increased repair and regeneration of bone tissue in cranial defect model rats compared to control rats at 12 weeks post-implantation. In conclusion, the LDH-CS-PFTα scaffolds exhibited excellent osteogenic differentiation and bone regeneration capability and hold great potential for applications in defined local bone regeneration.

Chitosan Wound Dressings Incorporating Exosomes Derived from MicroRNA-126-Overexpressing Synovium Mesenchymal Stem Cells Provide Sustained Release of Exosomes and Heal Full-Thickness Skin Defects in a Diabetic Rat Model.

There is a need to find better strategies to promote wound healing, especially of chronic wounds, which remain a challenge. We found that synovium mesenchymal stem cells (SMSCs) have the ability to strongly promote cell proliferation of fibroblasts; however, they are ineffective at promoting angiogenesis. Using gene overexpression technology, we overexpressed microRNA-126-3p (miR-126-3p) and transferred the angiogenic ability of endothelial progenitor cells to SMSCs, promoting angiogenesis. We tested a therapeutic strategy involving controlled-release exosomes derived from miR-126-3p-overexpressing SMSCs combined with chitosan. Our in vitro results showed that exosomes derived from miR-126-3p-overexpressing SMSCs (SMSC-126-Exos) stimulated the proliferation of human dermal fibroblasts and human dermal microvascular endothelial cells (HMEC-1) in a dose-dependent manner. Furthermore, SMSC-126-Exos also promoted migration and tube formation of HMEC-1. Testing this system in a diabetic rat model, we found that this approach resulted in accelerated re-epithelialization, activated angiogenesis, and promotion of collagen maturity in vivo. These data provide the first evidence of the potential of SMSC-126-Exos in treating cutaneous wounds and indicate that modifying the cells-for example, by gene overexpression-and using the exosomes derived from these modified cells provides a potential drug delivery system and could have infinite possibilities for future therapy. Stem Cells Translational Medicine 2017;6:736-747.

Hollow mesoporous ZSM-5 zeolite/chitosan ellipsoids loaded with doxorubicin as pH-responsive drug delivery systems against osteosarcoma.

The toxic risks and adverse effects of anticancer drugs on healthy tissues limit their wide clinical application. Herein, we for the first time fabricated hollow mesoporous ZSM-5/chitosan ellipsoids loaded with doxorubicin (HM-ZSM-5/CS/DOX) as pH-responsive drug delivery systems against osteosarcoma. The HM-ZSM-5 ellipsoids including a hollow core and a mesoporous shell could efficiently load DOX drugs with a loading efficiency of 95.8%. The CS layer was uniformly distributed on the HM-ZSM-5 ellipsoids that contributed to the pH-responsive release of DOX drugs. The controlled DOX release kinetics from the HM-ZSM-5/CS/DOX ellipsoids was fitted well with the Korsmeyer-Peppas model. The HM-ZSM-5/CS/DOX ellipsoids exhibited good biocompatibility due to the low DOX release rate in the neutral media that simulated healthy tissues or blood. Moreover, the cellular uptake of the HM-ZSM-5/CS/DOX ellipsoids took place in tumor cells, and the quick release of DOX significantly promoted the apoptosis of MG63 cells. The levels of MDA, LDH and CK markers for the HM-ZSM-5/CS/DOX group were lower than those for the free DOX group, suggesting no systemic toxicity to the heart. Therefore, the HM-ZSM-5/CS/DOX ellipsoids as novel pH-responsive drug delivery systems can effectively treat osteosarcoma without systemic toxicity.