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1.
Biochem Biophys Res Commun ; 710: 149599, 2024 May 28.
Article En | MEDLINE | ID: mdl-38608493

Osteoarthritis is a highly prevalent joint disease; however, effective treatments are lacking. Protopine (PTP) is an isoquinoline alkaloid with potent anti-inflammatory and antioxidant properties; however, it has not been studied in osteoarthritis. This study aimed to investigate whether PTP can effectively protect chondrocytes from ferroptosis. Primary mouse chondrocytes were treated with tert-butyl hydroperoxide (TBHP) to simulate oxidative stress in an in vitro model of osteoarthritis. Two concentrations of PTP (10 and 20 µg/mL) were validated for in vitro experiments. Cellular inflammation and metabolism were detected using RT-qPCR and western blotting (WB). Ferroptosis was assessed via WB, qPCR, reactive oxygen species (ROS) levels, lipid ROS, and immunofluorescence staining. In vitro, PTP significantly ameliorated chondrocyte inflammation and cytolytic metabolism and significantly suppressed chondrocyte ferroptosis through the activation of the Nrf2 pathway. The anterior cruciate ligament transection (ACLT) mouse model was used to validate the in vivo effects of PTP. The joint cartilage was assessed using the Osteoarthritis Research Society International (OARSI) score, Safranin O staining, and immunohistochemistry. The intra-articular administration of PTP alleviated cartilage inflammation and ferroptosis, as evidenced by the expression of MMP3, MMP13, COL2A1, GPX4, and Nrf2. Overall, we find that PTP exerted anti-ferroptosis and anti-inflammatory effects on chondrocytes to protect the articular cartilage.


Benzophenanthridines , Berberine Alkaloids , Ferroptosis , Osteoarthritis , Animals , Mice , Anti-Inflammatory Agents/pharmacology , Benzophenanthridines/pharmacology , Berberine Alkaloids/pharmacology , Chondrocytes/drug effects , Chondrocytes/metabolism , Ferroptosis/drug effects , Inflammation/metabolism , NF-E2-Related Factor 2/metabolism , Osteoarthritis/drug therapy , Osteoarthritis/metabolism , Osteoarthritis/pathology , Reactive Oxygen Species/metabolism
2.
Environ Sci Pollut Res Int ; 30(27): 71194-71208, 2023 Jun.
Article En | MEDLINE | ID: mdl-37162675

Freshwater blooms of harmful cyanobacteria in drinking water source-oriented shallow lakes affect public health and ecosystem services worldwide. Therefore, identifying 2-methylisoborneol (2-MIB)-producing cyanobacteria and predicting the risks of 2-MIB are critical for managing 2-MIB-infected water sources. Previous studies on the potential producers and risks of 2-MIB have focused on reservoirs or have been limited by the ecosystems of phytoplankton-dominated areas. We investigated the producers, distribution, and occurrence of 2-MIB in East Taihu Lake-a drinking water source-oriented shallow lake with macrophyte- and phytoplankton-dominated areas-from August 2020 to November 2021. We observed that Pseudanabaena sp. produces 2-MIB in this lake, as determined by the maximum correlation coefficient (R = 0.71, p < 0.001), maximum detection rate, and minimum false positive/negative ratio exhibited by this genus. Extreme odor events occurred in this lake during late summer and early autumn in 2021, with the mean 2-MIB concentration increasing to 727 ± 426 ng/L and 369 ± 176 ng/L in August and September, respectively. Moreover, the macrophyte-dominated area, particularly the wetland area, exhibited a significant decrease (p < 0.01) in bloom intensity and 2-MIB production during these extreme odor events. Pseudanabaena sp. outbreak was likely owing to eutrophication, seasonal gradients, and macrophyte reduction, considering that temporal trends were consistent with high water temperature, high total phosphorus levels, and low-light conditions. Moreover, 2-MIB production was sensitive to short-term hydrometeorological processes, with high water levels and radiant intensity enhancing 2-MIB production. The risk assessment results showed that the probability of 2-MIB concentration exceeding the odor threshold (10 ng/L) is up to 90% when the cell density of Pseudanabaena sp. reaches 1.8 × 107 cell/L; this risk is reduced to 50 and 25% at densities of < 3.8 × 105 cell/L and 5.6 × 104 cell/L, respectively. Our findings support calls for shallow lake management efforts to maintain a macrophyte-dominated state and control odorous cyanobacteria growth.


Cyanobacteria , Drinking Water , Drinking Water/microbiology , Lakes , Ecosystem , Phytoplankton , Eutrophication , Phosphorus/analysis , Risk Assessment , China
3.
J Environ Manage ; 342: 118154, 2023 Sep 15.
Article En | MEDLINE | ID: mdl-37207462

Macrophytes are of key importance to the structure and ecological services of shallow lakes and are sensitive to anthropogenic and natural perturbations. Ongoing eutrophication and hydrological regime change affect macrophytes through changes in water transparency and water level, which lead to a dramatic decrease in bottom light availability. Here an integrated dataset (2005-2021) of multiple environmental factors is used to demonstrate the driving forces and recovery potential of the macrophyte decline in East Taihu Lake by using a critical indicator, which is the ratio of the Secchi disk depth to the water depth (SD/WD). The macrophyte distribution area showed a remarkable decrease from 136.1 ± 9.7 km2 (2005-2014) to 66.1 ± 6.5 km2 (2015-2021). The macrophyte coverage in the lake and in the buffer zone decreased by 51.4% and 82.8%, respectively. The structural equation model and correlation analysis showed that the distribution and coverage of macrophytes decreased with the decrease in the SD/WD over time. Moreover, an extensive hydrological regime change, which caused a sharp decrease in SD and an increase in the water level, is likely to be the driving force that brought about the decline of macrophytes in this lake. The proposed recovery potential model shows that the SD/WD has been low in recent years (2015-2021), and that this SD/WD cannot ensure the growth of submerged macrophytes and is unlikely to ensure the growth of floating-leaved macrophytes, especially in the buffer zone. The approach developed in the present study provides a basis for the assessment of macrophyte recovery potential and the management of ecosystems in shallow lakes that suffer from macrophyte loss.


Ecosystem , Lakes , Water , Eutrophication , China
4.
Eur Radiol ; 33(2): 893-903, 2023 Feb.
Article En | MEDLINE | ID: mdl-36001124

OBJECTIVES: To quantify intra-tumor heterogeneity (ITH) in non-small cell lung cancer (NSCLC) from computed tomography (CT) images. METHODS: We developed a quantitative ITH measurement-ITHscore-by integrating local radiomic features and global pixel distribution patterns. The associations of ITHscore with tumor phenotypes, genotypes, and patient's prognosis were examined on six patient cohorts (n = 1399) to validate its effectiveness in characterizing ITH. RESULTS: For stage I NSCLC, ITHscore was consistent with tumor progression from stage IA1 to IA3 (p < 0.001) and captured key pathological change in terms of malignancy (p < 0.001). ITHscore distinguished the presence of lymphovascular invasion (p = 0.003) and pleural invasion (p = 0.001) in tumors. ITHscore also separated patient groups with different overall survival (p = 0.004) and disease-free survival conditions (p = 0.005). Radiogenomic analysis showed that the level of ITHscore in stage I and stage II NSCLC is correlated with heterogeneity-related pathways. In addition, ITHscore was proved to be a stable measurement and can be applied to ITH quantification in head-and-neck cancer (HNC). CONCLUSIONS: ITH in NSCLC can be quantified from CT images by ITHscore, which is an indicator for tumor phenotypes and patient's prognosis. KEY POINTS: • ITHscore provides a radiomic quantification of intra-tumor heterogeneity in NSCLC. • ITHscore is an indicator for tumor phenotypes and patient's prognosis. • ITHscore has the potential to be generalized to other cancer types such as HNC.


Carcinoma, Non-Small-Cell Lung , Head and Neck Neoplasms , Lung Neoplasms , Humans , Carcinoma, Non-Small-Cell Lung/pathology , Lung Neoplasms/pathology , Prognosis , Tomography, X-Ray Computed/methods
5.
J Hazard Mater ; 442: 130052, 2023 01 15.
Article En | MEDLINE | ID: mdl-36182878

The off-flavor compound 2-methylisoborneol (2-MIB) is generally associated with the proliferation and metabolism of filamentous cyanobacteria in shallow freshwater ecosystems. Here field monitoring in East Taihu Lake from July to October 2021, along with cultural experiments, was conducted to determine the impact of submerged macrophytes on the growth and 2-MIB production of filamentous cyanobacteria. Pseudanabaena sp. was identified as the 2-MIB producer with the highest detection rate (100%) and correlation coefficient (R=0.68, p < 0.001). The 2-MIB concentration and algal growth in the macrophyte-dominated zones were markedly decreased compared with those in the phytoplankton-dominated zone. Five submerged macrophytes classified into flat-leaf type (Vallisneria natans and Potamogeton crispus) and thin-leaf type (Hydrilla verticillata, Ceratophyllum demersum, and Myriophyllum spicatum) exhibited strong inhibition effects against Pseudanabaena sp.: Overall inhibition efficiencies (IEs) of 92.7% ± 6.8% and 92.7% ± 8.4% for cell growth and 2-MIB production were achieved, respectively. Moreover, the thin-leaf macrophytes exhibited significant higher IEs for cell growth (94.0% vs. 84.7%) and 2-MIB production (99.4% vs. 82.6%) than the flat-leaf macrophytes and can be selected as pioneer species in controlling odor problems. Nutrient uptake, increasing water clarity, shading effects, and allelopathic effects of the submerged macrophytes were found to be the dominant inhibition mechanisms.


Cyanobacteria , Hydrocharitaceae , Ecosystem , Hydrocharitaceae/metabolism , Lakes , Water
6.
Intractable Rare Dis Res ; 11(3): 158-160, 2022 Aug.
Article En | MEDLINE | ID: mdl-36200029

Cholangiocytic adenoma in the hilar bile duct is rare, and elevated IgG4 at the same time is extremely rare. This situation has not been reported in the literature. Nonetheless, the current case involved hilar biliary cystadenoma with elevated IgG4 levels. A 66-year-old man presented at this hospital with dark tea-colored urine. Preoperative imaging studies suggested hilar cholangiocarcinoma. This case demonstrates the difficulty of preoperative diagnosis of benign hilar lesions and the rarity of two combined benign lesions. A point of contention is whether this case should be treated with surgery or hormone therapy.

7.
Med Image Anal ; 81: 102539, 2022 10.
Article En | MEDLINE | ID: mdl-35926337

Visual representation extraction is a fundamental problem in the field of computational histopathology. Considering the powerful representation capacity of deep learning and the scarcity of annotations, self-supervised learning has emerged as a promising approach to extract effective visual representations from unlabeled histopathological images. Although a few self-supervised learning methods have been specifically proposed for histopathological images, most of them suffer from certain defects that may hurt the versatility or representation capacity. In this work, we propose CS-CO, a hybrid self-supervised visual representation learning method tailored for H&E-stained histopathological images, which integrates advantages of both generative and discriminative approaches. The proposed method consists of two self-supervised learning stages: cross-stain prediction (CS) and contrastive learning (CO). In addition, a novel data augmentation approach named stain vector perturbation is specifically proposed to facilitate contrastive learning. Our CS-CO makes good use of domain-specific knowledge and requires no side information, which means good rationality and versatility. We evaluate and analyze the proposed CS-CO on three H&E-stained histopathological image datasets with downstream tasks of patch-level tissue classification and slide-level cancer prognosis and subtyping. Experimental results demonstrate the effectiveness and robustness of the proposed CS-CO on common computational histopathology tasks. Furthermore, we also conduct ablation studies and prove that cross-staining prediction and contrastive learning in our CS-CO can complement and enhance each other. Our code is made available at https://github.com/easonyang1996/CS-CO.


Staining and Labeling , Supervised Machine Learning , Histological Techniques
8.
Phys Chem Chem Phys ; 24(28): 17329-17336, 2022 Jul 21.
Article En | MEDLINE | ID: mdl-35819000

Recently, theoretical search has found that a two-dimensional CuCl3 monolayer is a ferromagnetic semiconductor. Here, we apply density functional theory to study its geometrical structure, magnetic and electronic properties under the influence of a biaxial strain ε. It is found that the CuCl3 monolayer exhibits ferromagnetic ordering at the ground state with ε = 0 and its Curie temperature increases monotonously with respect to the biaxial strain, which can be increased to about 100 K at 10% tensile strain. When a compressive strain of about 6.8% is applied, a transition from the ferromagnetic to the antiferromagnetic state occurs. In addition to the transition of the magnetic ground state, the electronic band gaps of spin-up and spin-down electrons undergo direct-indirect and indirect-direct-indirect transitions at the tensile strains, respectively. The tunable magnetic and electronic properties investigated in this work are helpful in understanding the magnetism in the CuCl3 monolayer, which is useful for the design of spintronic devices based on ferromagnetic semiconductors.

9.
Nat Commun ; 13(1): 2120, 2022 Apr 19.
Article En | MEDLINE | ID: mdl-35440578

Inspired by gradient materials in nature, advanced engineering components with controlled structural gradients have attracted substantial research interests due to their exceptional combinations of properties. However, it remains challenging to generate structural gradients that penetrate through bulk materials, which is essential for achieving enhanced mechanical properties in metallic materials. Here, we report practical strategies to design controllable structural gradients in bulk metallic glasses (BMGs). By adjusting processing conditions, including holding time and/or controlling temperatures, of cryogenic thermal cycling and fast cooling, two different types of gradient metallic glasses (GMGs) with spatially gradient-distributed free volume contents can be synthesized. Both mechanical testing and atomistic simulations demonstrate that the spatial gradient can endow GMGs with extra plasticity. Such an enhanced mechanical property is governed by the gradient-induced deflection of shear deformation that fundamentally suppresses the unlimited shear localization on a straight plane that would be expected in BMGs without such a gradient.

10.
Inflammopharmacology ; 30(3): 1107-1117, 2022 Jun.
Article En | MEDLINE | ID: mdl-35391646

Osteoarthritis (OA) is a chronic joint disorder that causes cartilage degradation and subchondral bone abnormalities. Nangibotide, also known as LR12, is a dodecapeptide with considerable anti-inflammatory properties, but its significance in OA is uncertain. The aim of the study was to determine whether nangibotide could attenuate the progression of OA, and elucidate the underlying mechanism. In vitro experiments showed that nangibotide strongly inhibited TNF-α-induced osteogenic reduction, significantly enhanced osteoblast proliferation and prevented apoptosis in MC3T3-E1 cells. Male C57BL/6 J mice aged 2 months were randomly allocated to three groups: sham, ACLT, and ACLT with nangibotide therapy. Nangibotide suppressed ACLT-induced cartilage degradation and MMP-13 expression. MicroCT analysis revealed that nangibotide attenuated in vivo subchondral bone loss induced by ACLT. Histomorphometry results showed that nangibotide attenuated ACLT-induced osteoblast inhibition; TUNEL assays and immunohistochemical staining of cleaved-caspase3 further confirmed the in vivo anti-apoptotic effect of nangibotide on osteoblasts. Furthermore, we found that nangibotide exerted protective effects by suppressing TGF-ß signaling mediated by Smad2/3 to restore coupled bone remodeling in the subchondral bone. In conclusion, the findings suggest that nangibotide might exert a protective effect on the bone-cartilage unit and maybe an alternative treatment option for OA.


Cartilage, Articular , Osteoarthritis , Animals , Apoptosis , Disease Models, Animal , Lauric Acids , Male , Mice , Mice, Inbred C57BL , Oligopeptides , Osteoarthritis/drug therapy , Osteoarthritis/metabolism , Osteoblasts/metabolism , Rhodamines , Transforming Growth Factor beta/metabolism
11.
Phys Chem Chem Phys ; 24(13): 7797-7804, 2022 Mar 30.
Article En | MEDLINE | ID: mdl-35297445

Recently, extensive experimental and theoretical studies on two-dimensional materials have attracted enormous interest in exploring the properties of these materials by decorating their surfaces. In the present work, we present a detailed investigation of the structures, and electronic and magnetic properties of pristine, hydrogenated, and fluorinated BeO monolayers using the ab initio density functional theory approach. Structurally, the most stable adsorption sites are directly above the host Be atom for half-hydrogenation, above the middle of the Be-O bond for half-fluorination, and directly above the host Be atom and below the host O atom for full-hydrogenation and full-fluorination. Moreover, the electronic and magnetic properties of the BeO monolayer exhibit high sensitivity to chemical functionalization: half-hydrogenation induces nonmagnetic-magnetic transition and the reduction of the band gap reaches about 75%. Full-hydrogenation results in metallization of the BeO monolayer. Half-fluorination makes the BeO monolayer a 100% spin polarized material regardless of the adsorption site. However, depending on different adsorption sites, full-fluorination can produce either magnetically half-metallic or nonmagnetic semiconductor structures. These results demonstrate that the tunability of the electronic and magnetic properties of the BeO monolayer can be realized by chemical functionalization for future nano-electronic and spintronic device applications.

12.
Chin Med ; 17(1): 18, 2022 Feb 05.
Article En | MEDLINE | ID: mdl-35123541

BACKGROUND: Osteoarthritis (OA) is widely recognized as the most common chronic joint disease accompanied by progressive cartilage and subchondral bone damage. Toddalolactone (TOD), a natural compound extracted from Toddalia asiatica (L.) Lam., has been widely used in the treatment of stroke, rheumatoid arthritis, and oedema. Nevertheless, what TOD acts as in the pathogenesis and progression of OA hasn't been reported. In this investigation, we have aimed to determine how TOD affects OA in vitro and in vivo. METHODS: LPS (10 µg/ml) and IL-1ß (10 ng/ml) were employed to induce chondrocyte inflammation or RANKL to induce osteoclast differentiation in bone marrow derived macrophages (BMMs). The effects of TOD on chondrocyte inflammation and osteoclast differentiation were evaluated. Anterior cruciate ligament transection (ACLT) was performed to develop an OA animal model and study the effects of TOD. RESULTS: We found that TOD inhibited the expression of inflammatory and catabolic mediators (IL-6, IL-8, TNF-α, MMP2, MMP9, and MMP13) in inflammatory chondrocytes in vitro. Furthermore, TOD was proven to inhibit RANKL-induced-osteoclastogenesis and inhibit the expression of osteoclast marker genes. Our data also confirmed that TOD suppressed the destruction of articular cartilage and osteoclastogenesis via inhibiting the activation of NF-κB and MAPK signalling pathways. In the ACLT mouse model, we found that TOD attenuated cartilage erosion and inhibited bone resorption. CONCLUSIONS: These results showed that TOD can be adopted as a potential therapeutic agent for OA.

13.
Cell Prolif ; 54(12): e13142, 2021 Dec.
Article En | MEDLINE | ID: mdl-34632658

OBJECTIVES: Aseptic loosening (AL) is the most common reason of total hip arthroplasty (THA) failure and revision surgery. Osteolysis, caused by wear particles released from implant surfaces, has a vital role in AL. Although previous studies suggest that wear particles always lead to osteoblast programmed death in the process of AL, the specific mechanism remains incompletely understood and osteoblast ferroptosis maybe a new mechanism of AL. MATERIALS AND METHODS: CoCrMo nanoparticles (CoNPs) were prepared to investigate the influence of ferroptosis in osteoblasts and calvaria resorption animal models. Periprosthetic osteolytic bone tissue was collected from patients who underwent AL after THA to verify osteoblast ferroptosis. RESULTS: Our study demonstrated that CoNPs induced significant ferroptosis in osteoblasts and particles induced osteolysis (PIO) animal models. Blocking ferroptosis with specific inhibitor Ferrostatin-1 dramatically reduced particle-induced ferroptosis in vitro. Moreover, in osteoblasts, CoNPs significantly downregulated the expression of Nrf2 (nuclear factor erythroid 2-related factor 2), a core element in the antioxidant response. The overexpression of Nrf2 by siKeap1 or Nrf2 activator Oltipraz obviously upregulated antioxidant response elements (AREs) and suppressed ferroptosis in osteoblasts. Furthermore, in PIO animal models, the combined utilization of Ferrostatin-1 and Oltipraz dramatically ameliorated ferroptosis and the severity of osteolysis. CONCLUSIONS: These results indicate that CoNPs promote osteoblast ferroptosis by regulating the Nrf2-ARE signalling pathway, which suggests a new mechanism underlying PIO and represents a potential therapeutic approach for AL.


Antioxidant Response Elements , Bone-Implant Interface , Ferroptosis/drug effects , Metal Nanoparticles/adverse effects , NF-E2-Related Factor 2/metabolism , Osteoblasts/metabolism , Skull/metabolism , Vitallium/adverse effects , Animals , Cell Line , Mice , Osteolysis/chemically induced , Osteolysis/metabolism , Vitallium/pharmacology
14.
Sci Adv ; 7(36): eabe4758, 2021 Sep 03.
Article En | MEDLINE | ID: mdl-34516918

Metals containing abundant coherent twin boundaries (TBs) are able to sustain substantial plastic deformation without fracture due to shear-induced TB migration and sliding. Retaining ductility in these metals, however, has proven difficult because detwinning rapidly exhausts TB migration mechanisms at large deformation, whereas TB sliding was only evidenced for loading on very specific crystallographic orientations. Here, we reveal the intrinsic shear deformability of twins in nanocrystals using in situ nanomechanical testing and multiscale simulations and report extreme shear deformability through TB sliding up to 364%. Sliding-induced plasticity is manifested for orientations that are generally predicted to favor detwinning and shown to depend critically on geometric inhomogeneities. Normal and shear coupling are further examined to delineate a TB orientation-dependent transition from TB sliding to TB cracking. These dynamic observations reveal unprecedented mechanical properties in nanocrystals, which hold implications for improving metal processing by severe plastic deformation.

15.
Phys Chem Chem Phys ; 23(38): 22103-22109, 2021 Oct 06.
Article En | MEDLINE | ID: mdl-34580685

The discovery of two-dimensional monolayer CrI3 provides a promising possibility for developing spintronic devices. However, the low Curie temperature is an obstacle for practical applications. Here, based on the consideration of the superexchange interaction of ferromagnetic coupling, we investigate the effect of introducing I-vacancies and interstitial H-atoms on the Curie temperature of monolayer CrI3 by using first-principles calculations and Monte Carlo simulations. Our theoretical conclusions show that the Curie temperature of Cr8I23 (CrI2.875), Cr8I22 (CrI2.75) and Cr8I24H (CrI3H0.125) significantly increases to 97.0, 82.5 and 112.4 K, respectively. Moreover, the magnetic moment of the Cr atom increases from 3.10 to 3.45 and 3.46µB in monolayers Cr8I23 and Cr8I22, respectively. We provide more alternative approaches to effectively enhance the Curie temperature of monolayer CrI3, which will help both theoretical and experimental researchers to directly predict the change in Curie temperature of CrI3 and its analogs through structural information.

16.
Life Sci ; 278: 119528, 2021 Aug 01.
Article En | MEDLINE | ID: mdl-33894271

We aimed to identify RNA N6-methyladenosine methylation associated genes in osteoarthritis (OA), and to explore possible regulatory mechanisms of these RNA methylation associated genes. Bioinformatics analyses, including differential expression analysis, functional enrichment analysis, verification analysis, and box plot analysis, were conducted based on different datasets from OA and non-OA patients. Gene expression at mRNA and protein levels was determined by quantitative reverse transcription PCR, western blot and immunofluorescence. Interleukin 1ß (IL-1ß)-treated SW1353 cells was used as cell model. Lentiviral vector was used for over-expression METTL3 in vitro. CCK-8 assay kit was used to determine cell viability and inflammatory cytokines (IL-1α, IL-6, IL-8, IL-10 and TNF-α) was detected using ELISA kits. Bioinformatics analysis showed that METTL3 expression was decreased in OA group, which was confirmed in clinical samples. Expression of METTL3 was also reduced in IL-1ß-treated cells. Levels of inflammatory cytokines were obviously reduced in the METTL3 overexpression group, while IL-1ß treatment reversed such decrease caused by METTL3 overexpression (p < 0.05). Both METTL3 overexpression and IL-1ß treatment promoted expression of p65 protein and p-ERK (p < 0.01). Additionally, increased expression of MMP1 and MMP3, and decreased expression of MMP13, TIMP-1, and TIMP-2 at both mRNA and protein levels were observed in the METTL3 overexpression group when compared with the control group (p < 0.01). Expression of m6A methylation gene METTL3 was reduced in OA. METTL3 is involved in OA probably by regulating the inflammatory response. METTL3 overexpression may affect extracellular matrix degradation in OA by adjusting the balance between TIMPs and MMPs.


DNA Methylation , Extracellular Matrix/metabolism , Inflammation/metabolism , Methyltransferases/metabolism , Osteoarthritis/metabolism , RNA Helicases/metabolism , Arthroplasty, Replacement, Hip , Arthroplasty, Replacement, Knee , Chondrocytes/metabolism , Computational Biology , Disease Progression , Gene Expression Profiling , Gene Expression Regulation , Humans , Interleukin-1beta/metabolism , Oligonucleotide Array Sequence Analysis , Treatment Outcome
17.
Bioact Mater ; 6(8): 2372-2389, 2021 Aug.
Article En | MEDLINE | ID: mdl-33553822

Cartilage-targeting delivery of therapeutic agents is still an effective strategy for osteoarthritis (OA) therapy. Recently, scavenging for reactive oxygen species (ROS) and activating autophagy have been increasingly reported to treat OA effectively. In this study, we designed, for the first time, a dual-drug delivery system based on metal organic framework (MOF)-decorated mesoporous polydopamine (MPDA) which composed of rapamycin (Rap) loaded into the mesopores and bilirubin (Br) loaded onto the shell of MOF. The collagen II-targeting peptide (WYRGRL) was then conjugated on the surface of above nanocarrier to develop a cartilage-targeting dual-drug delivery nanoplatform (RB@MPMW). Our results indicated the sequential release of two agents from RB@MPMW could be achieved via near-infrared (NIR) laser irritation. Briefly, the rapid release of Br from the MOF shell exhibited excellent ROS scavenging ability and anti-apoptosis effects, however responsively reduced autophagy activity, to a certain extent. Meanwhile, following the NIR irradiation, Rap was rapidly released from MPDA core and further enhanced autophagy activation and chondrocyte protection. RB@MPMW continuously phosphorylated AMPK and further rescued mitochondrial energy metabolism of chondrocytes following IL-1ß stimulation via activating SIRT1-PGC-1α signaling pathway. Additionally, the cartilage-targeting property of peptide-modified nanocarrier could be monitored via Magnetic Resonance (MR) and IVIS imaging. More significantly, RB@MPMW effectively delayed cartilage degeneration in ACLT rat model. Overall, our findings indicated that the as-prepared dual-drug delivery nanoplatform exerted potent anti-inflammation and anti-apoptotic effects, rescued energy metabolism of chondrocytes in vitro and prevented cartilage degeneration in vivo, which thereby showed positive performance for OA therapy.

18.
Phys Chem Chem Phys ; 22(25): 14210-14215, 2020 Jul 07.
Article En | MEDLINE | ID: mdl-32555852

A thermodynamic model for the diameter- and length-dependent melting temperature Tm(D,L) of nanorods has been proposed from the perspective of the Gibbs free energy together with the size-dependent interface energy, where D and L denote the diameter and the length of the nanorods. As the model describes, Tm(D,L) decreases with a decrease in D and L, where the diameter effect is dominant while the length effect is secondary. Agreements between model predictions and the available experimental and molecular dynamics simulation results can be found for Sn and Cu nanorods, which enabled us to determine the size dependence of the magnetostructural transition temperature in MnBi nanorods. This work is helpful for the design and application of nanoscale devices.

19.
Int Immunopharmacol ; 82: 106376, 2020 Mar 09.
Article En | MEDLINE | ID: mdl-32163857

Osteoarthritis is a relatively common disorder of articular deterioration related to cartilage damage, subchondral bone remodelling, inflammation and metabolism. Agents that can inhibit cartilage degradation and osteoclastogenesis are required for the prevention and treatment of osteoarthritis. Esculentoside A, the highest concentration triterpene saponin isolated from the root of Phytolacca esculenta, has commonly been used for the treatment of chronic bronchitis. However, the role esculentoside A plays in ameliorating osteoarthritis has not been reported. We found that esculentoside A suppresses the expression of IL-1ß-induced inflammatory and metabolic factors (IL-6, IL-8, TNF-α, MMP2, MMP3 and MMP13). In addition, esculentoside A restrains osteoclast formation by inhibiting the marker gene expression of NFATc1 and c-Fos. Our results indicate that esculentoside A markedly suppresses IL-1ß-induced NF-κB and MAPK signalling pathway activation in chondrocytes, and inhibits RANKL-induced osteoclast precursor generation. Finally, treatment with esculentoside A inhibits the progressive cartilage degeneration and osteoclastogenesis in osteoarthritis mouse models. In summary, these results demonstrate that esculentoside A could be a latent therapeutic reagent for the treatment of osteoarthritis.

20.
Phys Chem Chem Phys ; 22(10): 5735-5739, 2020 Mar 11.
Article En | MEDLINE | ID: mdl-32104863

With structural miniaturization down to the nanoscale, some detectable parameters of materials no longer remain constant. For NiO nanoparticles example, Raman shift and Néel temperature increase while optical band gap decreases with increasing the nanoparticle size. Herein, we developed the analytic models to describe the size dependence of these above-mentioned seemingly uncorrelated parameters for NiO nanoparticles, based on the average coordination number-dependent cohesive energy model. Consistency between our theoretical predictions and the corresponding experimental results not only verified the accuracy of our developed models but also provided insight into the essentiality of cohesive energy in describing the effect of size on the materials properties of NiO nanoparticles.

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