Advanced biology最新文献

Dysfunction in adipose tissue can cause serious health problems, including obesity, type-2 diabetes, and cardiovascular disease, significantly reducing human life expectancy. Differences in differentiation and lipid accumulation in adipocytes reflect their functional status, making it important to characterize adipocytes by monitoring biophysical changes during adipogenic differentiation. However, there is currently no specific cell surface marker to separate mature adipocytes from non-adipose cells based on their lipid content, and separation of mature adipocytes is challenging due to handling limitations without fixation, antibody staining, or particle conjugation. Here, we report a biomarker-free, magnetic levitation-based method to detect density changes and quantify the accumulation of lipid-rich droplets within differentiating adipogenic cells. Magnetic levitation revealed density changes within preadipocytes differentiating towards mature adipocytes, with density decreasing over time as cells accumulated lipids. We then used lipid droplets as an intracellular marker to quantify lipid accumulation in single adipocytes during adipogenesis. The significant density changes correlated with cell morphology and lipid droplet morphology within the cytoplasm. For the first time, free-floating lipid vesicle density was measured using magnetic levitation. This unique method enables efficient detection and quantification of dynamically evolving lipid droplets in cells, proving beneficial for modeling lipid storage-related diseases and drug screening applications.

Human hepatocellular carcinoma (HCC) is the most common liver cancer and the third leading cause of cancer-related deaths worldwide. HCC is a malignant tumor that can lead to intrahepatic and extrahepatic metastases. Intercellular adhesion molecule 1 (ICAM-1) is involved in cancer metastasis. ICAM-1 enhances cell-cell interactions by promoting adhesion and facilitating cell movement within the extracellular matrix. Moreover, ICAM-1 is more abundant in cancerous hepatocytes than in non-cancerous ones. Chemokine (C-X-C motif) ligand 1 (CXCL1) is found in diverse cancers, including melanoma, breast, lung, pancreatic, colorectal, and prostate. Several studies show a correlation between CXCL1 overexpression and poor prognosis in cancer. CXCL1 has been identified as a candidate gene that could function as a clinically relevant biomarker in HCC. However, the role of CXCL1 in cancer metastasis in HCC is poorly delineated. In this study, Gene Expression Omnibus (GEO) database analysis revealed a positive correlation between CXCL1 level and the progression and metastasis of hepatocellular carcinoma patients. CXCL1 treatment facilitates cell movement through inducing ICAM-1 expression. The Phosphoinositide 3-kinase (PI3K)/Akt/Nuclear Factor kappa B (NF-kB) signaling pathway plays a crucial role in CXCL1-regulated ICAM-1 production and cell motility. Thus, CXCL1 represents a promising therapeutic target for treating metastatic hepatocellular carcinoma.

Bone metastasis is a devastating complication for advanced-stage prostate cancer patients. Osteocytes, as the primary mechanosensors in bone, have been recently investigated for their role in prostate cancer bone metastasis. In vivo findings show potential benefits of exercise as a preventative intervention strategy for bone metastasis. In contrast, in vitro studies indicate direct prostate cancer-osteocyte interactions under mechanical loading promote prostate cancer growth and migration. These findings are not consistent with in vivo results and may be more reflective of late-stage metastatic colonization. Here, the role of flow-stimulated osteocytes during early-stage bone metastasis, particularly prostate cancer-endothelial interactions, is examined. Flow-stimulated osteocytes reduce PC-3 prostate cancer cell adhesion and trans-endothelial migration by 32.3% and 40% compared to static controls. Both MLO-Y4 and primary murine osteocytes under mechanical loading regulate the extravasation distance and frequency of PC-3 cells in a microfluidic tissue model. Application of vascular cellular adhesion molecule 1 (VCAM-1) neutralizing antibody abolishes the difference in cancer cell adhesion, extravasation frequency, and number of extravasated PC-3 cells between static and flow-stimulated groups. Taken together, the role of osteocytes in early-stage bone metastasis using PC-3 cells as a model is demonstrated here, bridging the gap between in vitro and in vivo findings.

Diabetes mellitus is a chronic metabolic disorder that affects multiple organs, including the stomach. This research examines the effects of naringin and/or zinc on stomach and pancreatic tissues of streptozotocin-induced diabetic rats. Type 2 diabetes is induced by intraperitoneal injection of nicotinamide and streptozotocin. Three weeks after diabetes induction, rats receive eight weeks of treatment. Malondialdehyde and total antioxidant capacity are estimated colorimetrically. Asprosin and P-selectin levels are assessed via ELISA. Quantitative RT-PCR analysis of nuclear factor kappa B (NF-кB), peroxisome proliferator-activated receptor gamma (PPAR γ), and nuclear factor erythroid 2-related factor 2 (Nrf-2) genes is carried out. Tumor necrosis factor-alpha (TNF-α) is assessed immunohistochemically, and stomach and pancreatic tissues are examined histologically. Combined naringin and zinc treatment significantly reduces gastric Malondialdehyde, serum asprosin, and P-selectin levels in serum, stomach, and pancreas compared to diabetic rats. Additionally, gastric NF-кB expression is significantly lower, while PPAR γ and Nrf-2 expressions are significantly higher compared to diabetic rats. Immunohistochemical analysis and histopathological examination confirm these findings. In conclusion, combined naringin and zinc treatment significantly improves gastric alterations in diabetic rats by reducing oxidative stress and inflammation. Nonetheless, it shows no additional impacts on pancreatic tissue compared to naringin or zinc alone.

The central dogma describes the unidirectional flow of genetic information from DNA to proteins, leading to an underappreciation of the potential for the information contained in proteomes (the full set of proteins in an organism) to reflect broader biological processes such as lifespan. Here, this is addressed by examining how the size and composition of 276 proteomes from four vertebrate classes are related to lifespan. After accounting for the relationship between body weight and lifespan, lifespan is negatively correlated with proteome size in birds and, to a weaker extent, in fish, and positively correlated with lifespan in mammals. Proteome composition varies amongst the four vertebrate classes, but there is no evidence that any specific amino acid correlated with lifespan. The findings in relation to the role of dietary amino acid restriction are discussed on lifespan extension and raise questions about evolutionary and structural forces shaping proteome composition across species.

Corneal blindness remains a significant global health challenge, with limited treatment options due to donor tissue scarcity outside of the United States and inadequate in vitro models. This review analyzes the current state of cornea chip technology, addressing fundamental challenges and exploring future directions. Recent advancements in biomaterials and fabrication techniques are discussed that aim to recapitulate the complex structure and function of the human cornea, including the multilayered epithelium, organized stroma, and functional endothelium. The review highlights the potential of the cornea chips to revolutionize ocular research by offering more predictive and physiologically relevant models for drug screening, disease modeling, and personalized medicine. Current designs, their applications in studying drug permeability, barrier function, and wound healing, and their limitations in replicating native corneal architecture, are examined. Key challenges include integrating corneal curvature, basement membrane formation, and innervation. Applications are explored in modeling diseases like keratitis, dry eye disease, keratoconus, and Fuchs' endothelial dystrophy. Future directions include incorporating corneal curvature using hydraulically controlled systems, using patient-derived cells, and developing comprehensive disease models to accelerate therapy development and reduce reliance on animal testing.

Cancer-associated fibroblasts (CAFs) drive tumor progression through restructuring of the tumor microenvironment. This investigation aim to elucidate the function of molecular subtypes (MS) derived from cancer cells communication with CAFs, depicting the hallmarks of the tumor microenvironment and precise bladder cancer (BLCA) treatment. The BLCA data from TCGA and several external sources are utilized to generate a novel ligand, receptor, and transcription factor (LRT) associated molecular subtype and their corresponding score (LRT score). The LRT-mediated molecular subtype is identified via unsupervised clustering. LRT score is measured by principal component analysis. Then, the association of LRT clusters to established MS, immunophenotypes, and medical endpoints, together with BLCA treatment strategies is investigated. Two LRT clusters (A and B) are identified. LRT cluster (LRT score) can precisely propose immunophenotypes, classical MS, clinical outcomes, and BLCA therapeutic strategies. Cluster B (Low LRT score) represent a basal subtype and inflamed phenotype specified by high immunity against tumors and unfavorable clinical outcomes. Furthermore, it is highly sensitive to cancer immunotherapy; however, it has low sensitivity to antiangiogenic and targeted therapies. The novel LRT clusters with a strong association with biological characteristics and precise BLCA treatment strategies are derived from the communication between cancer cells and cancer-associated fibroblasts. The LRT may be a useful clinician tool for developing individualized treatment strategies.

Cell-like platforms are being studied intensively for their application in synthetic biology to mimic aspects of life in an artificial environment. Here, micrometer-sized, bifunctional microgels are used as an experimental platform to investigate the interplay of cell-free protein synthesis (CFPS) and in situ protein accumulation inside the microgel volume. In detail, microgels made of hyaluronic acid (HA) are first modified with different amounts of nitrilotriacetic acid (NTA) moieties to characterize the capability and maximum capacity of binding His-tag modified GFP. CFPS is optimized for the system used here, particularly when using a linear DNA template. Afterward, HA-microgels are functionalized with the linear DNA template and Ni²⁺-activated NTA moieties to bind in situ synthesized GFP-His. CFPS and parallel protein accumulation within the microgels are observed over time to determine the GFP-His binding to the microgel platform. With this approach, the study presents the first steps for a platform to study the temporal-spatial regulation of protein synthesis by tailored protein binding or release from the microgel matrix-based reaction environment.

This study aims to investigate the role and mechanism of luteolin in inflammation and phenotypic switch of vascular smooth muscle cells (VSMCs) in an arteriovenous fistula (AVF) model, for providing a potential agent for the prevention and therapy of AVF neointimal hyperplasia. In vivo, an AVF model is created in Sprague Dawley rats. In vitro, rat VSMCs are treated with platelet-derived growth factor-BB (PDGF-BB) to induce the phenotypic switch of VSMCs. Histological AVF changes are analyzed using hematoxylin-eosin. Western blot and quantitative real-time polymerase chain reaction (qRT-PCR) are utilized to detect prostaglandin-endoperoxide synthase 2 (PTGS2) expression. In vivo, luteolin inhibits neointima formation and reduces vimentin, α-SMA, MCP-1, MMP-9, TNF-α, and IL-6 levels. In vitro, under PDGF-BB treatment, luteolin inhibits proliferation and migration and reduces TNF-α, vimentin, α-SMA, MCP-1, MMP-9, and IL-6 levels in VSMCs. In rat AVF tissues, PTGS2 expression is increased. Luteolin inhibits PTGS2 expression in vivo and in vitro. PTGS2 overexpression reverses the role of luteolin in extracellular matrix protein expression, proliferation, inflammation, and migration in VSMCs treated with PDGF-BB. Altogether, in the AVF, luteolin inhibits proliferation, migration, the phenotypic switch of VSMCs, neointima formation, and the inflammatory response through inhibiting PTGS2 expression.

The decellularized human amniotic membrane (dHAM) has been evaluated as a biomaterial for various tissue engineering applications, notably as a skin dressing for wound healing. The decellularization process alters the composition and structure of the extracellular matrix consequently influencing its characteristics. The aim of the present study was to comparatively evaluate dHAM-E and dHAM-S prepared by enzymatic and salt solution treatment respectively for their microstructure using scanning electron microscopy (SEM), in vitro biocompatibility with mesenchymal stem cells (MSCs), and regenerative capability in full-thickness wound model in mice. The SEM results revealed increased porosity in dHAM-S and better MSC adhesion and proliferation as compared to dHAM-E. Moreover, wound healing capability assessed at day 7 and day 14 by histological analysis of the regenerated tissues indicated that the dHAM treated groups achieved greater re-epithelialization and remodeling than the untreated group. However, dHAM-S treated samples presented a more remodeled regenerated skin than the other groups. Furthermore, gene expression analysis of the regenerated skin displayed a higher expression of anti-inflammatory, proliferation, and keratinization marker genes in the dHAM treated groups. Overall, it was found that dHAMs are compatible with MSCs and improve wound healing. However, clear differences were observed in the bioactivity of the two dHAMs.