Crosstalk between Lipid Metabolism and Bone Homeostasis: Exploring Intricate Signaling Relationships.

Bone is a dynamic tissue reshaped by constant bone formation and bone resorption to maintain its function. The skeletal system accounts for approximately 70% of the total volume of the body, and continuous bone remodeling requires quantities of energy and material consumption. Adipose tissue is the main energy storehouse of the body and has a strong adaptive capacity to participate in the regulation of various physiological processes. Considering that obesity and metabolic syndrome have become major public health challenges, while osteoporosis and osteoporotic fractures have become other major health problems in the aging population, it would be interesting to explore these 2 diseases together. Currently, an increasing number of researchers are focusing on the interactions between multiple tissue systems, i.e., multiple organs and tissues that are functionally coordinated together and pathologically pathologically interact with each other in the body. However, there is lack of detailed reviews summarizing the effects of lipid metabolism on bone homeostasis and the interactions between adipose tissue and bone tissue. This review provides a detailed summary of recent advances in understanding how lipid molecules and adipose-derived hormones affect bone homeostasis, how bone tissue, as a metabolic organ, affects lipid metabolism, and how lipid metabolism is regulated by bone-derived cytokines.

Regulation of bone homeostasis: signaling pathways and therapeutic targets.

As a highly dynamic tissue, bone is continuously rebuilt throughout life. Both bone formation by osteoblasts and bone resorption by osteoclasts constitute bone reconstruction homeostasis. The equilibrium of bone homeostasis is governed by many complicated signaling pathways that weave together to form an intricate network. These pathways coordinate the meticulous processes of bone formation and resorption, ensuring the structural integrity and dynamic vitality of the skeletal system. Dysregulation of the bone homeostatic regulatory signaling network contributes to the development and progression of many skeletal diseases. Significantly, imbalanced bone homeostasis further disrupts the signaling network and triggers a cascade reaction that exacerbates disease progression and engenders a deleterious cycle. Here, we summarize the influence of signaling pathways on bone homeostasis, elucidating the interplay and crosstalk among them. Additionally, we review the mechanisms underpinning bone homeostatic imbalances across diverse disease landscapes, highlighting current and prospective therapeutic targets and clinical drugs. We hope that this review will contribute to a holistic understanding of the signaling pathways and molecular mechanisms sustaining bone homeostasis, which are promising to contribute to further research on bone homeostasis and shed light on the development of targeted drugs.

Arachidonic acid in aging: New roles for old players.

BACKGROUND: Arachidonic acid (AA), one of the most ubiquitous polyunsaturated fatty acids (PUFAs), provides fluidity to mammalian cell membranes. It is derived from linoleic acid (LA) and can be transformed into various bioactive metabolites, including prostaglandins (PGs), thromboxanes (TXs), lipoxins (LXs), hydroxy-eicosatetraenoic acids (HETEs), leukotrienes (LTs), and epoxyeicosatrienoic acids (EETs), by different pathways. All these processes are involved in AA metabolism. Currently, in the context of an increasingly visible aging world population, several scholars have revealed the essential role of AA metabolism in osteoporosis, chronic obstructive pulmonary disease, and many other aging diseases. AIM OF REVIEW: Although there are some reviews describing the role of AA in some specific diseases, there seems to be no or little information on the role of AA metabolism in aging tissues or organs. This review scrutinizes and highlights the role of AA metabolism in aging and provides a new idea for strategies for treating aging-related diseases. KEY SCIENTIFIC CONCEPTS OF REVIEW: As a member of lipid metabolism, AA metabolism regulates the important lipids that interfere with the aging in several ways. We present a comprehensivereviewofthe role ofAA metabolism in aging, with the aim of relieving the extreme suffering of families and the heavy economic burden on society caused by age-related diseases. We also collected and summarized data on anti-aging therapies associated with AA metabolism, with the expectation of identifying a novel and efficient way to protect against aging.

Release and Degradation Mechanism of Modified Polyvinyl Alcohol-Based Double-Layer Coated Controlled-Release Phosphate Fertilizer.

This study aims to improve the slow-release performance of a film material for a controlled-release fertilizer (CRF) while enhancing its biodegradability. A water-based biodegradable polymer material doped with biochar (BC) was prepared from modified polyvinyl alcohol (PVA) with polyvinylpyrrolidone (PVP) and chitosan (CTS), hereinafter referred to as PVA/PVP-CTSaBCb. An environmentally friendly novel controlled-release phosphate fertilizer (CRPF) was developed using PVA/PVP-CTS8%BC7% as the film. The effect of the PVA/PVP-CTS8%BC7% coating on the service life of the CRPF was investigated. The film was characterized via stress-strain testing, SEM, FTIR, XRD, and TGA analyses. The addition of the CTS modifier increased the stress of PVA/PVP-CTS8% by 7.6% compared with that of PVA/PVP owing to the decrease in the crystallinity of PVP/PVP-CTS8%. The hydrophilic -OH groups were reduced due to the mixing of CTS and PVA/PVP. Meanwhile, the water resistance of the PVA/PVP-CTS8%BC7% was improved. And the controlled-release service life of the CRPF was prolonged. Moreover, the addition of BC increased the crystallinity of the PVA/PVP-CTS8% by 10%, reduced the fracture elongation of the material, and further improved the biodegradability of the PVA/PVP-CTS8%BC7%. When the amount of BC added was 7%, the phosphorus release rate of the CRPF was 30% on the 28th day. Moreover, the degradation rate of the PVA/PVP-CTS8%BC7% polymer film was 35% after 120 days. This study provides basic data for applying water-based degradable polymer materials in CRFs.

Cascaded controlled delivering growth factors to build vascularized and osteogenic microenvironment for bone regeneration.

The process of bone regeneration is intricately regulated by various cytokines at distinct stages. The establishment of early and efficient vascularization, along with the maintenance of a sustained osteoinductive microenvironment, plays a crucial role in the successful utilization of bone repair materials. This study aimed to develop a composite hydrogel that would facilitate the creation of an osteogenic microenvironment for bone repair. This was achieved by incorporating an early rapid release of VEGF and a sustained slow release of BMP-2. Herein, the Schiff base was formed between VEGF and the composite hydrogel, and VEGF could be rapidly released to promote vascularization in response to the early acidic bone injury microenvironment. Furthermore, the encapsulation of BMP-2 within mesoporous silica nanoparticles enabled a controlled and sustained release, thereby facilitating the process of bone repair. Our developed composite hydrogel released more than 80% of VEGF and BMP-2 in the acidic medium, which was significantly higher than that in the neutral medium (about 60%). Moreover, the composite hydrogel demonstrated a significant improvement in the migratory capacity and tube formation ability of human umbilical vein endothelial cells (HUVECs). Furthermore, the composite hydrogel exhibited an augmented ability for osteogenesis, as confirmed by the utilization of ALP staining, alizarin red staining, and the upregulation of osteogenesis-related genes. Notably, the composite hydrogel displayed substantial osteoinductive properties, compared with other groups, the skull defect in the composite hydrogels combined with BMP-2 and VEGF was full of new bone, basically completely repaired, and the BV/TV value was greater than 80%. The outcomes of animal experiments demonstrated that the composite hydrogel effectively promoted bone regeneration in cranial defects of rats by leveraging the synergistic effect of an early rapid release of VEGF and a sustained slow release of BMP-2, thereby facilitating vascularized bone regeneration. In conclusion, our composite hydrogel has demonstrated promising potential for vascularized bone repair through the enhancement of angiogenesis and osteogenic microenvironment.

Measurement method of the RDC for the IPS and FFS-LCD.

The residual direct current (RDC) almost always brings serious image sticking (IS) problems in LCDs and is mainly related to the liquid crystal (LC) and photoaligned polyimide. In this paper, we propose a novel method, to the best of our knowledge, to evaluate the RDC of the FFS-LCDs through an optical measurement system. By this means, the accumulation and release of the ions can be seen distinctly through the transmittance-time curves with the voltage regulation. Hence, it is helpful to compare and analyze the RDC problem of different displays. Moreover, this method possesses the advantage of high efficiency and simplicity in order to benefit the material design in photoaligned polyimide or the LC.

REPIN1 regulates iron metabolism and osteoblast apoptosis in osteoporosis.

Osteoporosis is not well treated due to the difficulty of finding commonalities between the various types of it. Iron homeostasis is a vital component in supporting biochemical functions, and iron overload is recognized as a common risk factor for osteoporosis. In this research, we found that there is indeed evidence of iron accumulation in the bone tissue of patients with osteoporosis and REPIN1, as an origin specific DNA binding protein, may play a key role in this process. We revealed that sh-Repin1 therapy can rescue bone loss in an iron-overload-induced osteoporosis mouse model. Knockdown of Repin1 can inhibit apoptosis and enhance the resistance of osteoblasts to iron overload toxicity. REPIN1 promoted apoptosis by regulating iron metabolism in osteoblasts. Mechanistically, knockdown of Repin1 decreased the expression of Lcn2, which ameliorated the toxic effects of intracellular iron overload. The anti-iron effect of lentivirus sh-Repin1 was partially reversed or replicated by changing LCN2 expression level via si-RNA or plasmid, which indirectly verified the key regulatory role of LCN2 as a downstream target. Furthermore, the levels of BCL2 and BAX, which play a key role in the mitochondrial apoptosis pathway, were affected. In summary, based on the results of clinical specimens, animal models and in vitro experiments, for the first time, we proved the key role of REPIN1 in iron metabolism-related osteoporosis.

A facile synthesis of PEGylated Cu2O@SiO2/MnO2 nanocomposite as efficient photo-Fenton-like catalysts for methylene blue treatment.

The removal of toxic organic dyes from wastewater has received much attention from the perspective of environmental protection. Metal oxides see wide use in pollutant degradation due to their chemical stability, low cost, and broader light absorption spectrum. In this work, a Cu2O-centered nanocomposite Cu2O@SiO2/MnO2-PEG with an average diameter of 52 nm was prepared for the first time via a wet chemical route. In addition, highly dispersed MnO2 particles and PEG modification were realized simultaneously in one step, meanwhile, Cu2O was successfully protected under a dense SiO2 shell against oxidation. The obtained Cu2O@SiO2/MnO2-PEG showed excellent and stable photo-Fenton-like catalytic activity, attributed to integration of visible light-responsive Cu2O and H2O2-responsive MnO2. A degradation rate of 92.5% and a rate constant of 0.086 min-1 were obtained for methylene blue (MB) degradation in the presence of H2O2 under visible light for 30 min. Additionally, large amounts of •OH and 1O2 species played active roles in MB degradation. Considering the enhanced degradation of MB, this stable composite provides an efficient catalytic system for the selective removal of organic contaminants in wastewater.

Large scale transparency-adjustable mini-LED display with recoverable color gamut by a highly transparent electrochromic shutter.

In this work, a 25 inch (400 × 500 mm) transparency-adjustable mini-LED (TA-MLED) display is constructed of a transparent mini-LED (T-MLED) screen and an electrochromic (EC) shutter. The shutter shows a high transmittance of 86.5% with imperceptible color shift, enabling a perfect vision experience for see-through application. Furthermore, the response speed of the shutter is accelerated by optimal designs in splicing and driving. The coloring time is 55 s, and bleaching time is 36 s. Transmittance of the TA-MLED could be modulated from 3% to 60%. The transparency-adjustable property extends availability of the see-through display screens under strong light irradiations. The T-MLED's color gamut in CIE 1976 shrinks from 145.1% sRGB to 3.6% sRGB with 5161 cd/m2 of backside illumination, and is significantly enhanced to 83.5% sRGB with the active EC shutter.

Polypropylene Composites Reinforced by Nonmetallic from Waste Printed Circuit Boards Using Spout-Fluid Bed Coating with PP Particles Enhance Fluidization.

Nonmetallic materials recycled from waste printed circuit boards (N-WPCBs) were modified by coating KH-550 in a spout-fluid bed. To improve the effect of the modification, PP particles were used to enhance the fluidization quality of the N-WPCB particles in the coating modification. Then, the modified N-WPCBs were used as fillers to fabricate PP/N-WPCB composites. The method of coating in a spout-fluid bed with PP particles enhanced fluidization and showed the best modification effect compared to other coating methods. The FT-IR and SEM results demonstrated that interfacial bonding between N-WPCBs and PP could be enhanced by modified N-WPCBs, which improved the mechanical properties of the composites. When the mass ratio of PP to N-WPCBs is 100:75 and the dose of KH-550 is 4 phr, the flexural strength, tensile strength, and impact strength of the composites increase by 16.60%, 23.22%, and 23.64%, respectively. This would realize the high-value utilization of N-WPCBs with coating modification in the spout-fluid bed.

A Near-Infrared Light Triggered Composite Nanoplatform for Synergetic Therapy and Multimodal Tumor Imaging.

Transition-metal chalcogenide compounds with facile preparation and multifunctional elements act as ideal photothermal agents for cancer theranostics. This work synthesizes Cu7.2S4/5MoS2 composite nanoflowers and investigates the crystal growth mechanism to optimize the synthesis strategy and obtain excellent photothermal therapy agents. Cu7.2S4/5MoS2 exhibits a high photothermal conversion efficiency of 58.7% and acts as a theranostic nanoplatform and demonstrated an effective photothermal-chemodynamic-photodynamic synergetic therapeutic effect in both in vitro and in vivo tests. Moreover, Cu7.2S4/5MoS2 shows strong photoacoustic signal amplitudes and computed tomographic contrast enhancement in vivo. These results suggest a potential application of Cu7.2S4/5MoS2 composite nanoflowers as photo/H2O2-responsive therapeutic agents against tumors.