Interplay of Low-Density Lipoprotein Receptors, LRPs, and Lipoproteins in Pulmonary Hypertension.

The low-density lipoprotein receptor (LDLR) gene family includes LDLR, very LDLR, and LDL receptor-related proteins (LRPs) such as LRP1, LRP1b (aka LRP-DIT), LRP2 (aka megalin), LRP4, and LRP5/6, and LRP8 (aka ApoER2). LDLR family members constitute a class of closely related multifunctional, transmembrane receptors, with diverse functions, from embryonic development to cancer, lipid metabolism, and cardiovascular homeostasis. While LDLR family members have been studied extensively in the systemic circulation in the context of atherosclerosis, their roles in pulmonary arterial hypertension (PAH) are understudied and largely unknown. Endothelial dysfunction, tissue infiltration of monocytes, and proliferation of pulmonary artery smooth muscle cells are hallmarks of PAH, leading to vascular remodeling, obliteration, increased pulmonary vascular resistance, heart failure, and death. LDLR family members are entangled with the aforementioned detrimental processes by controlling many pathways that are dysregulated in PAH; these include lipid metabolism and oxidation, but also platelet-derived growth factor, transforming growth factor ß1, Wnt, apolipoprotein E, bone morpohogenetic proteins, and peroxisome proliferator-activated receptor gamma. In this paper, we discuss the current knowledge on LDLR family members in PAH. We also review mechanisms and drugs discovered in biological contexts and diseases other than PAH that are likely very relevant in the hypertensive pulmonary vasculature and the future care of patients with PAH or other chronic, progressive, debilitating cardiovascular diseases.

Probing TGF-ß1-induced cytoskeletal rearrangement by fluorescent-labeled silica nanoparticle uptake assay.

Cytoskeletal proteins are essential in maintaining cell morphology, proliferation, and viability as well as internalizing molecules in phagocytic and non-phagocytic cells. Orderly aligned cytoskeletons are disturbed by a range of biological processes, such as the epithelial-mesenchymal transition, which is observed in cancer metastasis. Although many biological methods have been developed to detect cytoskeletal rearrangement, simple and quantitative in vitro approaches are still in great demand. Herein, we applied a flow cytometry-based nanoparticle uptake assay to measure the degree of cytoskeletal rearrangement induced by transforming growth factor ß1 (TGF-ß1). For the assay, silica nanoparticles, selected for their high biocompatibility, were fluorescent-labeled to facilitate quantification with flow cytometry. Human keratinocyte HaCaT cells were treated with different concentrations of TGF-ß1 and then exposed to FITC-labeled silica nanoparticles. Increasing concentrations of TGF-ß1 induced gradual changes in cytoskeletal rearrangement, as confirmed by conventional assays. The level of nanoparticle uptake increased by TGF-ß1 treatment in a dose-dependent manner, indicating that our nanoparticle uptake assay can be used as a quick and non-destructive approach to measure cytoskeletal rearrangement.

An injectable micelle-hydrogel hybrid for localized and prolonged drug delivery in the management of renal fibrosis.

Localized delivery, comparing to systemic drug administration, offers a unique alternative to enhance efficacy, lower dosage, and minimize systemic tissue toxicity by releasing therapeutics locally and specifically to the site of interests. Herein, a localized drug delivery platform ("plum‒pudding" structure) with controlled release and long-acting features is developed through an injectable hydrogel ("pudding") crosslinked via self-assembled triblock polymeric micelles ("plum") to help reduce renal interstitial fibrosis. This strategy achieves controlled and prolonged release of model therapeutics in the kidney for up to three weeks in mice. Following a single injection, local treatments containing either anti-inflammatory small molecule celastrol or anti-TGFß antibody effectively minimize inflammation while alleviating fibrosis via inhibiting NF-κB signaling pathway or neutralizing TGF-ß1 locally. Importantly, the micelle-hydrogel hybrid based localized therapy shows enhanced efficacy without local or systemic toxicity, which may represent a clinically relevant delivery platform in the management of renal interstitial fibrosis.

Thickness-wise growth technique for human articular chondrocytes to fabricate three-dimensional cartilage grafts.

INTRODUCTION: Cutting the cost of manufacturing is important for extending the use of tissue-engineered therapeutic products. The present study aimed to develop a simple method for fabrication of cartilaginous tissues for regenerative therapy, utilizing the phenomenon where human articular chondrocytes grow thickness-wise and spontaneously form three-dimensionally thick tissues. METHODS: Normal human articular chondrocytes (NHACs) were cultured with varying concentrations of transforming growth factor beta 1 (TGF-ß1) and/or fibroblast growth factor-2 (FGF-2) to optimize the culture condition for thickness-wise growth of chondrocytes. Next, the tissues grown in the optimal condition were subjected to re-differentiation culture in attached and detached states to assess differentiation capacity by evaluating secreted factors, histological analysis, and a gene expression assay. RESULTS: NHACs grew thickness-wise efficiently in the presence of 1 ng/mL TGF-ß1 and 10 ng/mL FGF-2. After two weeks of culture, NHACs grew with 11-fold higher thickness and 16-fold higher cell number compared to cells which were neither treated with TGF-ß1 nor with FGF-2. These thickness-wise-grown chondrocytes could be re-differentiated by a differentiation medium according to the increase in melanoma inhibitory activity (MIA) and positive safranin-O staining. Interestingly, the cartilaginous gene expression was considerably different between the attached and detached conditions even in the same culture medium, indicating the necessity of detachment and shrinkage to achieve further differentiation. CONCLUSIONS: Spontaneous thickness-wise growth might provide a simple tissue-engineering method for manufacturing cartilaginous 3D tissues.

Maternal supplementation of seaweed-derived polysaccharides improves intestinal health and immune status of suckling piglets.

The experiment investigated the effect of maternal dietary supplementation of seaweed-derived polysaccharides (SDP) (-SDP v. +SDP, n   20) from day 83 of gestation until weaning (day 28) on selected sow faeces and piglet digesta microbiota populations, piglet small-intestinal morphology, and intestinal nutrient transporter and inflammatory cytokine gene expression at birth, 48 h after birth and weaning. The effect of maternal dietary treatment on the piglet gene expression profile of inflammatory cytokines in the colon following a lipopolysaccharide (LPS) challenge was also investigated. Dietary SDP reduced sow faecal Enterobacteriaceae gene numbers at parturition. Small-intestinal morphology, nutrient transporter and cytokine gene expression in newborn piglets did not differ between maternal dietary treatments (P > 0·10). At 48 h after birth, sodium-glucose-linked transporter 1 gene expression was down-regulated in the ileum of piglets suckling the SDP-supplemented sows compared with those suckling the basal sows (P = 0·050). There was a SDP × LPS challenge interaction on IL-1 and IL-6 gene expression in the colon of piglets (P < 0·05). The gene expression of IL-1 and IL-6 was down-regulated in the LPS-challenged colon of piglets suckling the SDP sows compared with those suckling the basal sows (P < 0·05). However, there was no difference in IL-1 and IL-6 gene expression in the unchallenged colon between treatment groups. At weaning, piglets suckling the SDP-supplemented sows had increased villus height in the jejunum and ileum compared with those suckling the basal-fed sows (P < 0·05). In conclusion, maternal dietary SDP supplementation enhanced the immune response of suckling piglets and improved gut morphology, making them more immune competent to deal with post-weaning adversities.

Ameliorating effects of traditional Chinese medicine preparation, Chinese materia medica and active compounds on ischemia/reperfusion-induced cerebral microcirculatory disturbances and neuron damage.

Ischemic stroke and ischemia/reperfusion (I/R) injury induced by thrombolytic therapy are conditions with high mortality and serious long-term physical and cognitive disabilities. They have a major impact on global public health. These disorders are associated with multiple insults to the cerebral microcirculation, including reactive oxygen species (ROS) overproduction, leukocyte adhesion and infiltration, brain blood barrier (BBB) disruption, and capillary hypoperfusion, ultimately resulting in tissue edema, hemorrhage, brain injury and delayed neuron damage. Traditional Chinese medicine (TCM) has been used in China, Korea, Japan and other Asian countries for treatment of a wide range of diseases. In China, the usage of compound TCM preparation to treat cerebrovascular diseases dates back to the Han Dynasty. Even thousands of years earlier, the medical formulary recorded many classical prescriptions for treating cerebral I/R-related diseases. This review summarizes current information and underlying mechanisms regarding the ameliorating effects of compound TCM preparation, Chinese materia medica, and active components on I/R-induced cerebral microcirculatory disturbances, brain injury and neuron damage.

NK cells and T cells cooperate during the clinical course of colorectal cancer.

Recent evidence suggests that natural killer (NK) cells are typically defective in infiltrating solid tumors, with the exception of gastrointestinal stromal tumors (GIST). Interestingly, however, infrequently infiltrating NK cells do not appear to have a direct effect on tumor progression. Here, prompted by the recent evidence that NK cell and T cell crosstalk may trigger, or enhance, tumor antigen-specific immune responses, we have tested the clinical significance of this reciprocal signaling. To this end, a tissue microarray constructed with 1410 colorectal carcinoma (CRC) patient specimens was stained with NK and T cell antigen-specific monoclonal antibodies, utilizing the immunoperoxidase staining technique. Cut-off scores for positive (>4 NK cells) and negative (≤4 NK cells) NK cell CRC patient samples were determined using receiver operating characteristic curve analysis. Using this approach, NK cells were detected in 423 (30%) of the 1410 CRC specimens evaluated. The number of NK cells was >4 in only 132 (9%) of CRC samples. Correlation of the immunohistochemical staining results together with analysis of the clinical course of the disease revealed that the infiltration of colorectal tumors with both NK cells and CD8+ T cells is associated with prolonged patient survival. In contrast, infiltration of tumors with NK cells in combination with CD3+ and CD4+ T lymphocytes had no detectable effect on the clinical course of the disease. These results suggest that NK cell and CD8+ T cell crosstalk in the tumor microenvironment may benefit patient outcome and further, that the enumeration of infiltrating NK and CD8+ T cells in CRC tumors may provide useful prognostic information.