SPARC: a potential target for functional nanomaterials and drugs

Systematic Mendelian Randomization Exploring Druggable Genes for Hemorrhagic Strokes

Patients with hemorrhagic stroke have high rates of morbidity and mortality, and drugs for prevention are very limited. Mendelian randomization (MR) analysis can increase the success rate of drug development by providing genetic evidence. Previous MR analyses only analyzed the role of individual drug target genes in hemorrhagic stroke; therefore, we used MR analysis to systematically explore the druggable genes for hemorrhagic stroke. We sequentially performed summary-data-based MR analysis and two-sample MR analysis to assess the associations of all genes within the database with intracranial aneurysm, intracerebral hemorrhage, and their subtypes. Validated genes were further analyzed by colocalization. Only genes that were positive in all three analyses and were druggable were considered desirable genes. We also explored the mediators of genes affecting hemorrhagic stroke incidence. Finally, the associations of druggable genes with other cardiovascular diseases were analyzed to assess potential side effects. We identified 56 genes that significantly affected hemorrhagic stroke incidence. Moreover, TNFSF12, SLC22A4, SPARC, KL, RELT, and ADORA3 were found to be druggable. The inhibition of TNFSF12, SLC22A4, and SPARC can reduce the risk of intracranial aneurysm, subarachnoid hemorrhage, and intracerebral hemorrhage. Gene-induced hypertension may be a potential mechanism by which these genes cause hemorrhagic stroke. We also found that blocking these genes may cause side effects, such as ischemic stroke and its subtypes. Our study revealed that six druggable genes were associated with hemorrhagic stroke, and the inhibition of TNFSF12, SLC22A4, and SPARC had preventive effects against hemorrhagic strokes.

In Vivo Effects of Bay 11-7082 on Fibroid Growth and Gene Expression: A Preclinical Study

Current medical therapies for fibroids have major limitations due to their hypoestrogenic side effects. Based on our previous work showing the activation of NF-kB in fibroids, we hypothesized that inhibiting NF-kB in vivo would result in the shrinkage of tumors and reduced inflammation. Fibroid xenografts were implanted in SCID mice and treated daily with Bay 11-7082 (Bay) or vehicle for two months. Bay treatment led to a 50% reduction in tumor weight. RNAseq revealed decreased expression of genes related to cell proliferation, inflammation, extracellular matrix (ECM) composition, and growth factor expression. Validation through qRT-PCR, Western blotting, ELISA, and immunohistochemistry (IHC) confirmed these findings. Bay treatment reduced mRNA expression of cell cycle regulators (CCND1, E2F1, and CKS2), inflammatory markers (SPARC, TDO2, MYD88, TLR3, TLR6, IL6, TNFα, TNFRSF11A, and IL1β), ECM remodelers (COL3A1, FN1, LOX, and TGFβ3), growth factors (PRL, PDGFA, and VEGFC), progesterone receptor, and miR-29c and miR-200c. Collagen levels were reduced in Bay-treated xenografts. Western blotting and IHC showed decreased protein abundance in certain ECM components and inflammatory markers, but not cleaved caspase three. Ki67, CCND1, and E2F1 expression decreased with Bay treatment. This preclinical study suggests NF-kB inhibition as an effective fibroid treatment, suppressing genes involved in proliferation, inflammation, and ECM remodeling.

3D Bioprinted Human Skin Model Recapitulating Native-Like Tissue Maturation and Immunocompetence as an Advanced Platform for Skin Sensitization Assessment

Physiologically-relevant in vitro skin models hold the utmost importance for efficacy assessments of pharmaceutical and cosmeceutical formulations, offering valuable alternatives to animal testing. Here, an advanced immunocompetent 3D bioprinted human skin model is presented to assess skin sensitization. Initially, a photopolymerizable bioink is formulated using silk fibroin methacrylate, gelatin methacrylate, and photoactivated human platelet releasate. The developed bioink shows desirable physicochemical and rheological attributes for microextrusion bioprinting. The tunable physical and mechanical properties of bioink are modulated through variable photocuring time for optimization. Thereafter, the bioink is utilized to 3D bioprint "sandwich type" skin construct where an artificial basement membrane supports a biomimetic epidermal layer on one side and a printed pre-vascularized dermal layer on the other side within a transwell system. The printed construct is further cultured in the air-liquid interface for maturation. Immunofluorescence staining demonstrated a differentiated keratinocyte layer and dermal extracellular matrix (ECM)-remodeling by fibroblasts and endothelial cells. The biochemical estimations and gene-expression analysis validate the maturation of the printed model. The incorporation of macrophages further enhances the physiological relevance of the model. This model effectively classifies skin irritative and non-irritative substances, thus establishing itself as a suitable pre-clinical screening platform for sensitization tests.

Interference with SPARC inhibits Benzophenone-3 induced ferroptosis in osteoarthritis: Evidence from bioinformatics analyses and biological experimentation

The aim of this study is to conduct a thorough evaluation of the association between Benzophenone-3 (BP-3) exposure and OA, offering critical insights into the underlying mechanisms involved. The National Health and Nutrition Examination Survey (NHANES) database was utilized to investigate the correlation between BP-3 and osteoarthritis. Proteomic sequencing from clinical sample and the PharmMapper online tool were employed to predict the biological target of BP-3. Cellular molecular assays and transfection studies were performed to verify the prediction from bioinformatics analyses. Through cross-sectional analysis of the NHANES database, we identified BP-3 as a risk factor for OA development. The results of proteomic sequencing showed that Secreted Protein Acidic and Rich in Cysteine (SPARC) was significantly elevated in the area of damage compared to the undamaged area. SPARC was also among the potential biological targets of BP-3 predicted by the online program. Through in vitro cell experiments, we further determined that the toxicological effects of BP-3 may be due to SPARC, which elevates intracellular GPX4 levels, activates the glutathione system, and promotes lipid peroxidation to mitigate ferroptosis. Inhibiting SPARC expression has been shown to reduce inflammation and ferroptosis in OA contexts. This research provides an expansive understanding of BP-3's influence on osteoarthritis development. We have identified SPARC as a potent target for combating chondrocyte ferroptosis in BP-3-associated osteoarthritis.

GP60 and SPARC as albumin receptors: key targeted sites for the delivery of antitumor drugs

Albumin is derived from human or animal blood, and its ability to bind to a large number of endogenous or exogenous biomolecules makes it an ideal drug carrier. As a result, albumin-based drug delivery systems are increasingly being studied. With these in mind, detailed studies of the transport mechanism of albumin-based drug carriers are particularly important. As albumin receptors, glycoprotein 60 (GP60) and secreted protein acidic and rich in cysteine (SPARC) play a crucial role in the delivery of albumin-based drug carriers. GP60 is expressed on vascular endothelial cells and enables albumin to cross the vascular endothelial cell layer, and SPARC is overexpressed in many types of tumor cells, while it is minimally expressed in normal tissue cells. Thus, this review supplements existing articles by detailing the research history and specific biological functions of GP60 or SPARC and research advances in the delivery of antitumor drugs using albumin as a carrier. Meanwhile, the deficiencies and future perspectives in the study of the interaction of albumin with GP60 and SPARC are also pointed out.

Obesity and Bone Mineral Density Protection Paradox in Chronic Kidney Disease: Secreted Protein Acidic and Rich in Cysteine as a Piece of the Puzzle?

Obesity is a health condition that represents a risk factor for numerous diseases and complications. However, obesity might also have-to some extent-some "benefits" in certain situations. This includes potential bone protection in patients suffering from chronic kidney disease. In an attempt to explain such a paradox, we highlight secreted protein acidic and rich in cysteine (SPARC) as a hypothetical mediator of this protection. Indeed, SPARC properties provide a logical rationale to describe such bone protection via its overexpression combined with its calcium-binding and collagen-binding properties. We believe that exploring such hypotheses could open new doors to elucidate unknown pathways towards developing a new generation of molecular therapies.