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Our findings demonstrated that the biphasic hierarchical ECM scaffold represents a novel and effective biomaterial that can be used in the treatment of osteochondral defect.

Tendon to bone (enthesis) rupture, which may cause disability and persistent pain, shows high rate of re‐rupture after surgical repair. Tendon or enthesis scaffolds have been widely studied, but few of these materials can recapitulate the tissue continuity. Thus, this study is conducted to prepare a triphasic decellularized bone‐fibrocartilage‐tendon (D‐BFT) composite scaffold. The D‐BFT scaffold is developed using a combination of physical, chemical, and enzymatic treatments using liquid nitrogen, Triton‐X 100, sodium‐dodecyl sulfate, and DNase I, which effectively removes the cell components while preserving the biological composite and microstructure. Moreover, the mechanical properties of D‐BFT are highly preserved and similar to those of the human Achilles tendon. Additionally, in vitro, mesenchymal stem cells (MSCs) adhered, proliferated, and infiltrated into the D‐BFT scaffold, and MSC differentiation is confirmed by up‐regulation of osteogenic‐related and tenogenic‐related genes. The repair outcomes are explored by applying the D‐BFT scaffold in the model of femur‐tibia defects in vivo, which shows good repair results. Thus, the D‐BFT scaffold developed in this study is a promising graft for enthesis regeneration.

Aims/IntroductionIn previous studies, hydrogen gas (H2) administration has clearly shown effectiveness in inhibiting diabetes. Here, we evaluated whether subcutaneous injection of H2 shows enhanced efficacy against type 2 diabetes mellitus induced in mice by a high‐fat diet and low‐dose streptozotocin treatment.Material and MethodsH2 was injected subcutaneously at a dose of 1 mL/mouse/week for 4 weeks. Type 2 diabetes mellitus‐associated parameters were then evaluated to determine the effectiveness of subcutaneous H2 administration.ResultsThe bodyweight of H2‐treated mice did not change over the course of the experiment. Compared with the untreated control animals, glucose, insulin, low‐density lipoprotein and triglyceride levels in the serum were significantly lower in treated mice, whereas high‐density lipoprotein cholesterol in the serum was significantly higher. Glucose tolerance and insulin sensitivity were both improved in H2‐treated mice. Diabetic nephropathy analysis showed significant reductions in urine volume, urinary total protein and β2‐microglobulin, kidney/bodyweight ratio, and kidney fibrosis associated with subcutaneous injection of H2.ConclusionsSubcutaneous injection of H2 significantly improves type 2 diabetes mellitus and diabetic nephropathy‐related outcomes in a mouse model, supporting further consideration of subcutaneous injection as a novel and effective route of clinical H2 administration.

Background The gut microbiota (GM)–bone axis has emerged as a crucial mediator of bone homeostasis. Estrogen deficiency–induced bone loss is closely associated with an altered GM. However, the underlying mechanisms remain unclear. Objectives We sought to explore the putative effects of GM on estrogen deficiency–induced bone loss and determine a potential mechanism. Methods Fecal samples collected from postmenopausal women with osteoporosis (PMO) and with normal bone mass (PMN) were examined by 16S ribosomal RNA (rRNA) gene sequencing and analysis. Prevotella histicola, a typical species of Prevotella, was orally given to female C57BL6/J mice after ovariectomy [ovariectomized (OVX)]. The primary outcomes were changes in bone microstructures as measured by micro–computed tomography scanning and bone histomorphometry analysis. Secondary outcomes included changes in osteoclast activity, the expression of osteoclastogenic cytokines, and gut permeability, which were measured by ELISA, qRT-PCR, western blot, and immunofluorescence. Results As demonstrated through 16S rRNA gene sequencing and analysis, the GM in the PMO group featured a significantly decreased proportion of the genus Prevotella in comparison with that in the PMN group (∼60%, P < 0.05). In animal experiments, P. histicola–treated OVX mice maintained a relatively higher bone volume than OVX controls. Mechanistically, the protective effects of P. histicola on bone mass were found to be associated with its modulation of gut permeability as well as its inhibitory effects on osteoclast activity which function by attenuating osteoclastogenic cytokine expression. Conclusions The GM diversity and composition between the PMN and PMO groups were significantly different. In particular, the proportion of the genus Prevotella was notably higher in the PMN group, demonstrating its potential bone-protective effects on osteoporosis. Further animal study using osteoporotic mice showed P. histicola could prevent estrogen deficiency–induced bone loss through the GM–bone axis. Thus, P. histicola may serve as a therapeutic agent or target for osteoporosis treatment.

Hypericin (Hyp) is traditionally used as an antidepressant and antiviral agent. It selectively accumulates in spheroids and is also used as a photosensitizer in the photodynamic therapy of cancer. The present study aimed to investigate the cytotoxic effect of Hyp-mediated photodynamic therapy (Hyp-PDT) on cell growth and apoptosis of K562 leukemia cells, and to examine the underlying mechanisms. Hyp-PDT was performed with different light intensities (0.1, 0.3 and 0.5 mW/cm2), different concentrations of Hyp (0, 0.2, 0.4 and 0.8 µg/ml) and different durations of irradiation (0, 2, 4 and 8 min) in order to select the optimal conditions for subsequent experiments. A concentration of 0.4 µg/ml Hyp with a 5 h drug-light interval and 4 min irradiation at 0.3 mW/cm2 light intensity was selected as the optimal conditions. The effects of Hyp-PDT on apoptosis were determined by detecting morphological changes under microscopy and by performing western blot analysis. The results revealed that Hyp-PDT suppressed cell viability in a light intensity-, dose- and irradiation duration-dependent manner. The expression levels of cleaved caspase-9, cleaved caspase-3 and phosphorylated-C-Jun N terminal kinase (JNK) l were significantly upregulated following Hyp-PDT. These results indicated that Hyp-PDT decreased cell viability and induced mitochondria-caspase-dependent apoptosis in the K562 cells through regulation of the JNK pathway. These findings suggest that Hyp-PDT may be developed as an effective treatment for leukemia.

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