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Recently, bone marrow endothelial cells (BMECs) were found to play an important role in regulating bone homeostasis. However, few studies utilized BMECs to treat bone metabolic diseases including osteoporosis. Here, we reported bioinspired nanovesicles (BNVs) prepared from human induced pluripotent stem cells-derived endothelial cells under hypoxia culture through an extrusion approach. Abundant membrane C-X-C motif chemokine receptor 4 conferred these BNVs bone-targeting ability and the endothelial homology facilitated the BMEC tropism. Due to their unique endogenous miRNA cargos, these BNVs re-educated BMECs to secret cytokines favoring osteogenesis and anti-inflammation. Owing to the conversion of secretory phenotype, the osteogenic differentiation of bone mesenchymal stem cells was facilitated, and the M1-macrophage-dominant pro-inflammatory microenvironment was ameliorated in osteoporotic bones. Taken together, this study proposed BMEC-targeting nanovesicles treating osteoporosis viaconverting the skeletal endothelium-associated secretory phenotype.

The complex pathogenesis of osteoporosis includes excessive bone resorption, insufficient bone formation and inadequate vascularization, a combination which is difficult to completely address with conventional therapies. Engineered exosomes carrying curative molecules show promise as alternative osteoporosis therapies, but depend on specifically-functionalized vesicles and appropriate engineering strategies. Here, we developed an exosome delivery system based on exosomes secreted by mesenchymal stem cells (MSCs) derived from human induced pluripotent stem cells (iPSCs). The engineered exosomes BT-Exo-siShn3, took advantage of the intrinsic anti-osteoporosis function of these special MSC-derived exosomes and collaborated with the loaded siRNA of the Shn3gene to enhance the therapeutic effects. Modification of a bone-targeting peptide endowed the BT-Exo-siShn3an ability to deliver siRNA to osteoblasts specifically. Silencing of the osteoblastic Shn3gene enhanced osteogenic differentiation, decreased autologous RANKL expression and thereby inhibited osteoclast formation. Furthermore, Shn3gene silencing increased production of SLIT3 and consequently facilitated vascularization, especially formation of type H vessels. Our study demonstrated that BT-Exo-siShn3could serve as a promising therapy to kill three birds with one stone and implement comprehensive anti-osteoporosis effects.

Ginsenoside Rg2 has been previously reported to reduce glucose production and adipogenesis in adipose tissue. However, the effects of ginsenosides Rg2 on hepatic lipid metabolism remain vacant. In this study, we found that ginsenoside Rg2 treatment significantly attenuated oleic acid and palmitic acid (OA&PA)-induced intracellular lipid deposition and oxidative stress in mouse primary hepatocytes. C57BL/6J mice that are fed with a high-fat diet (HFD) and treated with ginsenosides Rg2 displayed decreased body weight, reversed hepatic steatosis, and improved glucose tolerance and insulin sensitivity. Ginsenoside Rg2 administration significantly ameliorated HFD-induced hepatic oxidative stress and apoptosis. Moreover, Ginsenoside Rg2 had a good affinity with Sirtuin1 (SIRT1) and regulated its expression in vivo and in vitro. Deficiency of SIRT1 eliminated the therapeutic effect of ginsenoside Rg2 on lipid accumulation and overproduction of reactive oxygen species (ROS) in OA&PA-induced mice primary hepatocytes. Ginsenoside Rg2 treatment failed to alter the lipid and glucose disorder in hepatic SIRT1 deficient mice feeding on HFD. SIRT1 deficiency dissolves the therapeutic effect of ginsenoside Rg2 on oxidative stress and hepatocyte apoptosis induced by HFD. In summary, ginsenoside Rg2 plays a therapeutic role in HFD-induced hepatosteatosis of mice by decreasing the lipogenesis process and improving antioxidant capacity in an SIRT1-dependent manner.

ObjectiveImpaired hepatic fatty acids oxidation results in lipid accumulation and redox imbalance, promoting the development of fatty liver diseases and insulin resistance. However, the underlying pathogenic mechanism is poorly understood. Kru¨ppel-like factor 16 (KLF16) is a transcription factor that abounds in liver. We explored whether and by what mechanisms KLF16 affects hepatic lipid catabolism to improve hepatosteatosis and insulin resistance.DesignKLF16 expression was determined in patients with non-alcoholic fatty liver disease (NAFLD) and mice models. The role of KLF16 in the regulation of lipid metabolism was investigated using hepatocyte-specific KLF16-deficient mice fed a high-fat diet (HFD) or using an adenovirus/adeno-associated virus to alter KLF16 expression in mouse primary hepatocytes (MPHs) and in vivo livers. RNA-seq, luciferase reporter gene assay and ChIP analysis served to explore the molecular mechanisms involved.ResultsKLF16 expression was decreased in patients with NAFLD, mice models and oleic acid and palmitic acid (OA and PA) cochallenged hepatocytes. Hepatic KLF16 knockout impaired fatty acid oxidation, aggravated mitochondrial stress, ROS burden, advancing hepatic steatosis and insulin resistance. Conversely, KLF16 overexpression reduced lipid deposition and improved insulin resistance via directly binding the promoter of peroxisome proliferator-activated receptor α (PPARα) to accelerate fatty acids oxidation and attenuate mitochondrial stress, oxidative stress in db/dband HFD mice. PPARα deficiency diminished the KLF16-evoked protective effects against lipid deposition in MPHs. Hepatic-specific PPARα overexpression effectively rescued KLF16 deficiency-induced hepatic steatosis, altered redox balance and insulin resistance.ConclusionsThese findings prove that a direct KLF16–PPARα pathway closely links hepatic lipid homeostasis and redox balance, whose dysfunction promotes insulin resistance and hepatic steatosis.

Weaning is a stressful event associated with gastrointestinal disorders and increased disease susceptibility. Many studies have reported the changes that happened in the gut of various mammals such as pigs and rats after weaning. These findings suggest that the development of intestinal tract mainly is affected at the time of weaning through interfering in the differentiation and proliferation of intestinal stem cells. Weaning stress stimulates the rapid differentiation and proliferation of intestinal stem cells in order to adjust to changes caused by weaning, which are mainly manifested as deeper crypt depth and decreased intestine villus height. However, the accelerated cellular process may lead to an increase in the proportion of immature intestinal epithelial cells and goblet cells, which affect intestinal permeability and reduce the gut-barrier function against toxins and pathogens. This review briefly describes the effects coforticotrophin-releasing factor (CRF), epidermal growth factor (EGF) and polyamines on the differentiation and proliferation of intestinal stem cells after weaning and discusses its possible underlying regulatory mechanisms. Firstly, weaning stress activates CRF to binds its receptors, which induces proinflammatory responses and promote rapid differentiation and proliferation of intestinal stem cells to a larger fraction of immature intestinal epithelial cells and goblet cells. Secondly, the lack of EGF after weaning inhibits the expression of goblet cell maturation factors and makes it difficult for goblet cells and intestinal epithelial cells to mature. Finally, diet and endogenous synthesis lead to excessive polyamines in the intestine, which promote the proliferation of intestinal stem cells by regulating the expression of human antigen R (HuR) and other related genes at the time of weaning.

Numerous experimental studies have demonstrated that a series of remodeling processes occurred in the adipose tissue during the weaning, such as differentiation. Fibroblasts in the breast at weaning stage could re-differentiate into mature adipocytes. Many transcriptional factors were involved in these processes, especially the PPARγ, C/EBP, and SREBP1. There is cell apoptosis participating in the breast tissue degeneration and secretory epithelial cells loss during weaning. In addition, hormones, especially the estrogen and pituitary hormone, play a vital role in the whole reproductive processes. In this review, we mainly focus on the underlying regulated mechanisms of differentiation of adipose tissue and apoptosis of breast cell to provide a specific insight into the physiological changes during weaning.

Supercapacitors have been attracting significant attention as promising energy storage devices. However, the voltage window limitation associated with electrolyte solutions has hindered the improvement of their capacitance. To address this issue and enhance the energy storage capabilities of general traditional supercapacitors, we put forward the dipole-induced effects observed in the theoretical framework of the electric double-layer structure. The molecular dynamics results demonstrate that, compared to traditional systems, an improvement of over 50% in integral capacitance at low voltages is achieved. Moreover, a new material-based experimental results obtained from a dielectric supercapacitor employing a hydrated electrolyte solution corroborated the effectiveness of our proposed model, yielding consistent outcomes. We attribute the large capacitance variation to the reorientation of the dipoles, which induces the neutral-to-bilayer transition and the overscreening-to-steric transition, consistent with the polarization process of the polymer in the experiment. We further investigate the capacitance variations under different dipole parameters, such as varying the number of layers, different number densities and different spacings, thereby enriching the experimental results with additional conclusions not previously obtained. This work presents a novel approach that exploits dipole-induced capacitance effects, paving the way for further advances in the field of energy storage technology.

Hepatic lipid disorder impaired mitochondrial homeostasis and intracellular redox balance, triggering development of non-alcohol fatty liver disease (NAFLD), while effective therapeutic approach remains inadequate. Ginsenosides Rc has been reported to maintain glucose balance in adipose tissue, while its role in regulating lipid metabolism remain vacant. Thus, we investigated the function and mechanism of ginsenosides Rc in defending high fat diet (HFD)-induced NAFLD.

The recent random batch Ewald algorithm, originating from a stochastic approximation, performs 1 order of magnitude faster than the mainstream algorithms such as the particle–particle particle-mesh method for handling of long-range electrostatics in large-scale simulations. However, this algorithm fails to fully capture the long-range electrostatic correlations. Here, we demonstrate that, when incorporating a known screening condition in the stochastic approximation, the algorithm could be simply amended without the loss of any efficiency.