Structure of the Harmonin PDZ2 and coiled-coil domains in a complex with CDHR2 tail and its implications.

Harmonin is a protein containing multiple PDZ domains and is required for the development and maintenance of hair cell stereocilia and brush border microvilli. Mutations in the USH1C gene can cause Usher syndrome type 1C, a severe inheritable disease characterized by the loss of hearing and vision. Here, by solving the high-resolution crystal structure of Harmonin PDZ2 and coiled-coil domains in a complex with the tail of cadherin-related family member 2, we demonstrated that mutations located in the Harmonin PDZ2 domain and found in patients could affect its stability, and thus, the target binding capability. The structure also implies that the coiled-coil domain could form antiparallel dimers under high concentrations, possibly when Harmonin underwent liquid-liquid phase separation in the upper tip-link density in hair cell stereocilia or microvilli of enterocytes of the intestinal epithelium. The crystal structure, together with the biochemical analysis, provided mechanistic implications for Harmonin mutations causing Usher syndrome, non-syndromic deafness, or enteropathy.

CXCR4 antagonist delivery on decellularized skin scaffold facilitates impaired wound healing in diabetic mice by increasing expression of SDF-1 and enhancing migration of CXCR4-positive cells.

C-X-C chemokine receptor type 4 (CXCR4) is an alpha-chemokine receptor specific for stromal cell-derived factor 1 (SDF-1 also called CXCL12). The antagonist of CXCR4 can mobilize CD34+ cells and hematopoietic stem cells from bone marrow within several hours, and it has an efficacy on diabetes ulcer through acting on the SDF-1/CXCR4 axis. In this study, we investigated for the first time whether the antagonist of CXCR4 (Plerixafor/AMD3100) delivered on acellular dermal matrix (ADM) may accelerate diabetes-impaired wound healing. ADM scaffolds were fabricated from nondiabetic mouse skin through decellularization processing and incorporated with AMD3100 to construct ADM-AMD3100 scaffold. Full-thickness cutaneous wound in streptozotocin (STZ)-induced diabetic mice were treated with ADM, AMD3100, or ADM-AMD3100. 21 days after treatment, wound closure in ADM-AMD3100-treated mice was more complete than ADM group and AMD3100 group, and it was accompanied by thicker collagen formation. Correspondingly, diabetic mice treated with ADM-AMD3100 demonstrated prominent neovascularization (higher capillary density and vascular smooth muscle actin), which were accompanied by up-regulated mRNA levels of SDF-1 and enhanced migration of CXCR4 in the granulation tissue. Our results demonstrate that ADM scaffold provide perfect niche for loading AMD3100 and ADM-AMD3100 is a promising method for diabetic wound healing mainly by increasing expression of SDF-1 and enhancing migration of CXCR4-positive cells.

Raman spectroscopy enables noninvasive biochemical identification of the collagen regeneration in cutaneous wound healing of diabetic mice treated with MSCs.

Mesenchymal stem cells (MSCs) had been reported as a novel therapeutic strategy for non-healing diabetic cutaneous wound mainly by promoting the formation of extracellular matrix (ECM) and neovasculature. Collagen regeneration is one of the key processes of ECM remodeling in wound healing. Accordingly, rapid assessment of the collagen content in a noninvasive manner can promptly provide objective evaluation for MSC therapy of cutaneous wound healing and strength evidence to adjust therapeutic regimen. In the present study, noninvasive Raman microspectroscopy was used for tracing the regeneration status of collagen during diabetic wound healing with MSCs. Wound tissues of normal mice, diabetic mice, and MSC-treated diabetic mice were subjected to Masson trichrome staining assay and submitted to spectroscopic analysis by Raman microspectroscopy after wounding 7, 14, and 21 days. Masson trichrome staining demonstrated that there was more collagen deposition in diabetic + MSCs group relative to diabetic group. The relative intensity of Raman collagen peak positions at 937, 1004, 1321, 1452, and 1662 cm-1 increased in MSC-treated diabetic group compared to diabetic group, although normal mice group had the highest relative intensity of collagen peak bands. Correlation analysis suggested that the spectral bands had a high positive correlation with the collagen intensity detected by Masson trichrome staining in wound tissues of three groups. Our results demonstrate that Raman microspectroscopy has potential application in rapidly and quantitatively assessing diabetic wound healing with MSCs by monitoring collagen variation, which may provide a novel method for the study of skin regeneration.

Comparison of PD-L1 expression and MMR status between primary and matched metastatic lesions in patients with cervical cancer.

PURPOSE: Programmed death-ligand 1 (PD-L1) and DNA mismatch repair (MMR) are considered predictive biomarkers for immunotherapy in cervical cancer. However, their expression in primary tumors and metastases does not always match affecting the course of treatment. We investigated the consistency of their expression in primary and matched recurrent/metastatic lesions from patients with cervical cancer. METHODS: Primary and matched recurrent/metastatic specimens from patients with recurrent cervical cancer (n = 194) were stained for PD-L1 and MMR (MLHI, MSH6, MSH2, and PMS2) using immunohistochemistry. The degree of consistency of PD-L1 and MMR expression in these lesions was analyzed. RESULTS: The inconsistency rate of PD-L1 expression in primary and recurrent/metastatic lesions was 33.0%, and it varied between the recurrence sites. Positive PD-L1 rate in primary lesions was lower (15.4%) than that in recurrent/metastatic lesions (30.4%). The discordance rate of MMR expression between primary and recurrent/metastatic lesions was 4.1%. CONCLUSION: We conclude that to use PD-L1 as a predictive biomarker for immunotherapy, analysis of both metastatic and primary lesions may be required. High consistency rate of MMR expression between primary and metastatic lesions suggests that testing primary lesions alone can be sufficient for guiding the course of therapy, thereby solving the difficulty of obtaining recurrent/metastatic specimens in clinic.

Silica-Decorated NiAl-Layered Double Oxide for Enhanced CO/CO2 Methanation Performance.

CO/CO2 hydrogenation has attracted much attention as a pathway to achieve carbon neutrality and production of synthetic natural gas (SNG). In this work, two-dimensional NiAl layered double oxide (2D NiAl-LDO) has been successfully decorated by SiO2 nanoparticles derived from SiCl4 and used as CO/CO2 methanation catalysts. The as-obtained H-SiO2-NiAl-LDO exhibited a large specific surface area of 201 m2/g as well as high ratio of metallic Ni0 species and surface adsorption oxygen that were beneficial for low-temperature methanation of CO/CO2. The conversion of CO methanation was 99% at 400 °C, and that of CO2 was 90% at 350 °C. At 250 °C, the CO methanation reached 85% whereas that of CO2 reached 23% at 200 °C. We believe that this provides a simple method to improve the methanation performance of CO and CO2 and a strategy for the modification of other similar catalysts.

Reduced Graphene Oxide Incorporated Acellular Dermal Composite Scaffold Enables Efficient Local Delivery of Mesenchymal Stem Cells for Accelerating Diabetic Wound Healing.

Chronic skin wounds caused by diabetes mellitus (DM) have been acknowledged as one of the most intractable complications. Local transplantation of mesenchymal stem cells (MSCs) is a promising method, but strategies for stabilizing and efficiently delivering active MSCs according to the wound circumstance with high proteolysis remain the main barrier. Hereon, the study demonstrates the feasibility of incorporating reduced graphene oxide (RGO) nanoparticles with an acellular dermal matrix (ADM) to improve physicochemical characteristics of natural scaffold material and fabricate a highly efficient local transplantation system for MSCs in diabetic wound healing. Under the influence of RGO nanoparticles, the ADM-RGO composite scaffolds achieved high stability and strong mechanical behaviors. In vitro, conductive ADM-RGO scaffolds demonstrated an admirable milieu for stem cells adhesion and proliferation. After having been cocultured with MSCs, the ADM-RGO-MSC composite scaffolds were transplanted into the full-thickness wound of a diabetic model that was induced by streptozotocin (STZ) to evaluate its effects. As a result, the ADM-RGO composite scaffold delivered with MSCs supported robust vascularization and collagen deposition as well as rapid re-epithelialization during diabetic wound healing. Overall, the versatile nature of the ADM-RGO composite scaffold makes it an efficient transplanting mediator for pluripotent stem cells in tissue engineering applications. The composite scaffold delivered with MSCs presents a promising approach for nonhealing diabetic wounds.

The impact of subchronic low-dose exposure to nonylphenol on depression-like behaviors in high-sucrose and high-fat diet induced rats.

OBJECTIVE: We investigated the impact of subchronic low-dose exposure to nonylphenol (NP) on depression-like behaviors and synaptic morphological plasticity in the context of a high-sucrose/high-fat diet in rats. METHODS: Male Sprague Dawley (SD) rats were randomly divided into 8 groups (n = 10 per group), as follows: rats fed a normal-diet (ND), as the control (C-ND); rats fed a normal diet and gavaged with NP at a dose of 0.02 mg/kg/day (NP-L-ND), 0.2 mg/kg/day (NP-M-ND) or 2 mg/kg/day (NP-H-ND); rats fed a high-sucrose/high-fat diet (HSHFD), as the HSHFD control (C-HSHFD); rats fed a HSHFD and gavaged with NP at a dose of 0.02 mg/kg/day (NP-L-HSHFD), 0.2 mg/kg/day (NP-M-HSHFD) or 2 mg/kg/day (NP-H-HSHFD). Elevated plus maze was used to evaluate anxiety behavior. Open field test was used to evaluate locomotor activity. Cyclooxygenase-2 expression in hippocampal tissue was measured by immunohistochemistry. The ultrastructure of hippocampal mitochondria and the synaptic plasticity were observed by transmission electron microscopy. RESULTS: Significant interactions between HSHFD and NP-H were observed, reflected by the time spent exploring the open arms, time spent in the center area, distance traveled in the center area and total distance traveled (p < 0.05). Exposure to NP-H-HSHFD resulted in swelling of the mitochondria, associated with an increased number of disordered and partially disrupted cristae compared with the control group. Synaptic interface curvatures and postsynaptic density thickness decreased as the NP dose increased among the treatment groups. Co-exposure to HSHFD and NP showed an increase in synaptic cleft width compared with the HSHFD-only and NP-only exposure groups (p < 0.05). COX-2 expression and integral optical density value increased as the NP dose increased among the NP treatment groups (p < 0.05). CONCLUSION: Subchronic low-dose exposure to NP might induce alterations in depression-like behaviors, synaptic morphological plasticity and COX-2 expression in the hippocampus. Co-exposure to NP and HSHFD had significantly more dissimilarities.

Acellular dermal matrix scaffolds coated with connective tissue growth factor accelerate diabetic wound healing by increasing fibronectin through PKC signalling pathway.

The regional injection of connective tissue growth factor (CTGF) for diabetic wound healing requires multiple components and results in a substantial loss of its biological activity. Acellular dermal matrix (ADM) scaffolds are optimal candidates for delivering these factors to local ischaemic environments. In this study, we explored whether CTGF loaded on ADM scaffolds can enhance fibronectin (FN) expression to accelerate diabetic wound healing via the protein kinase C (PKC) signalling pathway. The performance of CTGF and CTGF + PKC inhibitor, which were loaded on ADM scaffolds to treat dorsal skin wounds in streptozotocin-induced diabetic mice, was evaluated with naked ADM as a control. Wound closure showed that ADM scaffolds loaded with CTGF induced greater diabetic wound healing in the early stage of the wound in diabetic mice. Moreover, ADM scaffolds loaded with CTGF obviously increased the expression of FN both at the mRNA and protein levels, whereas the expression of FN was significantly reduced in the inhibitor group. Furthermore, the ADM + CTGF group, which produce FN, obviously promoted alpha-smooth muscle actin and transforming growth factor-beta expression and enhanced neovasculature and collagen synthesis at the wound sites. ADM scaffolds loaded with CTGF + PKC inhibitor delayed diabetic wound healing, indicating that FN expression was mediated by the PKC signalling pathway. Our findings offer new perspectives for the treatment of diabetic wound healing and suggest a rationale for the clinical evaluation of CTGF use in diabetic wound healing.

PEGylated graphene oxide-mediated quercetin-modified collagen hybrid scaffold for enhancement of MSCs differentiation potential and diabetic wound healing.

Nanoscale delivery based on polyethylene glycol (PEG)ylated graphene oxide (GO-PEG) merits attention for biomedical applications owing to its functional surface modification, superior solubility/biocompatibility and controllable drug release capability. However, impaired skin regeneration in applications of these fascinating nanomaterials in diabetes is still limited, and critical issues need to be addressed regarding insufficient collagen hyperplasia and inadequate blood supply. Therefore, a high-performance tissue engineering scaffold with biocompatible and biodegradable properties is essential for diabetic wound healing. Natural and artificial acellular dermal matrix (ADM) scaffolds with spatially organized collagen fibers can provide a suitable architecture and environment for cell attachment and proliferation. Here, a novel collagen-nanomaterial-drug hybrid scaffold was constructed from GO-PEG-mediated quercetin (GO-PEG/Que)-modified ADM (ADM-GO-PEG/Que). The resulting unique and versatile hybrid scaffold exhibited multiple advantages, including the following: a biocompatible, cell-adhesive surface for accelerating mesenchymal stem cell (MSC) attachment and proliferation; superior stability and adjustability of the conduction potential of quercetin for inducing the differentiation of MSCs into adipocytes and osteoblasts; and a biodegradable nanofiber interface for promoting collagen deposition and angiogenesis in diabetic wound repair. This study provides new prospects for the design of innovative GO-PEG-based collagen hybrid scaffolds for application in efficient therapeutic drug delivery, stem cell-based therapies, tissue engineering and regenerative medicine.

Anti-inflammatory activity studies on the stems and roots of Jasminum lanceolarium Roxb.

Jasminum lanceolarium Roxb is an important traditional Chinese medicine. Its stems and roots have been used for the treatment of rheumatism and fever while the leaves are used as an anti-inflammatory agent to relieve pain. In order to support its traditional Chinese medicinal uses, five animal models were designed and the anti-inflammatory and analgesic properties of the 70% EtOH-H2O extracts of J. lanceolarium (EJL) were investigated. Meanwhile, biochemical parameters such as cyclooxygenase-2 (COX-2), 5-lipoxygenase (5-LOX) in blood serum of rats exposed to acute (carrageenan) inflammation model were evaluated. At doses of 400 mg/kg, EJL exhibited higher anti-inflammation effect than that of indomethacin and better analgesic activity than that of aspirin (P<0.001). Furthermore, eleven isolated compounds including six lignanoids (1, 2, 6, 7, 8, and 11) and five iridoids (3, 4, 5, 9, and 10) were isolated from the active extracts and showed significant anti-inflammatory activities with the IC50 values of 1.76-5.22 mg/mL, respectively, when testing their inhibitory effects on phospholipase A2 in vitro. The results demonstrated that the possible anti-inflammatory mechanisms might be attributed to inhibit the hydrolysis of membrane phospholipids, production on both COX-2 and 5-LOX, and then finally inhibit the release of prostaglandins (PGs), which suggested that EJL had a non-selective inhibitory effect on the release or actions of these mediators, and might be a dual LOX-COX inhibitor for the treatment of inflammation from the natural resource. The studies on the animals and the inflammatory mediators, along with the bioactive compounds presumed that the existences of iridoids and lignanoids could be response for their bioactivities of the whole plants.