CASIN and AMD3100 enhance endothelial cell proliferation, tube formation and sprouting

Acetyl-CoA synthetase 2 alleviates brain injury following cardiac arrest by promoting autophagy in brain microvascular endothelial cells

INTRODUCTION

Brain injury is a common sequela following cardiac arrest (CA), with up to 70% of hospitalized patients dying from it. Brain microvascular endothelial cells (BMVECs) play a crucial role in post-cardiac arrest brain injury (PCABI). However, the effects and mechanisms of targeting BMVEC energy metabolism to mitigate brain injury remain unclear.

METHODS

We established a mouse model of cardiac arrest by injecting potassium chloride into the right internal jugular vein. Mass spectrometry detected targeted changes in short-chain fatty acids and energy metabolism metabolites in the CA/CPR group compared to the sham group. Mice with overexpressed ACSS2 in BMVECs were created using an AAV-BR1 vector, and ACSS2 knockout mice were generated using the CRE-LOXP system. The oxygen glucose deprivation/re-oxygenation (OGD/R) model was established to investigate the role and mechanisms of ACSS2 in endothelial cells in vitro.

RESULTS

Metabolomics analysis revealed disrupted cerebral energy metabolism post-CA/CPR, with decreased acetyl-CoA and amino acids. Overexpression of ACSS2 in BMVECs increased acetyl-CoA levels and improved neurological function. Vascular endothelial cell-specific ACSS2 knockout mice exhibited reduced aortic sprouting in vitro. Overexpression of ACSS2 improved endothelial dysfunction following oxygen glucose deprivation/re-oxygenation (OGD/R) and influenced autophagy by interacting with transcription factor EB (TFEB) and modulating the AMP-activated protein kinase α (AMPKα) pathway.

CONCLUSION

Our study shows that ACSS2 modulates the biological functions of BMVECs by promoting autophagy. Enhancing energy metabolism via ACSS2 may target PCABI treatment development.

Novel scaffold platforms for simultaneous induction osteogenesis and angiogenesis in bone tissue engineering: a cutting-edge approach

Despite the recent advances in the development of bone graft substitutes, treatment of critical size bone defects continues to be a significant challenge, especially in the elderly population. A current approach to overcome this challenge involves the creation of bone-mimicking scaffolds that can simultaneously promote osteogenesis and angiogenesis. In this context, incorporating multiple bioactive agents like growth factors, genes, and small molecules into these scaffolds has emerged as a promising strategy. To incorporate such agents, researchers have developed scaffolds incorporating nanoparticles, including nanoparticulate carriers, inorganic nanoparticles, and exosomes. Current paper provides a summary of the latest advancements in using various bioactive agents, drugs, and cells to synergistically promote osteogenesis and angiogenesis in bone-mimetic scaffolds. It also discusses scaffold design properties aimed at maximizing the synergistic effects of osteogenesis and angiogenesis, various innovative fabrication strategies, and ongoing clinical studies.

Newly developed MEIS inhibitor selectively blocks MEIS High prostate cancer growth and induces apoptosis

Prostate cancer (PCa) is the second most diagnosed cancer in males. Understanding the molecular mechanism and investigation of novel ways to block PCa growth or metastasis are vital and a medical necessity. In this study, we examined differential expression of MEIS1/2/3 and its associated factors in PCa cell lines. MEIS1/2/3 content, reactive oxygen species, and cell cycle status were analyzed in PCa cells post MEIS inhibitor (MEISi) treatments, which is developed in our laboratory as a first-in-class small molecule inhibitor. A correlation was detected between MEIS content and MEISi IC50 values of PCa cells. MEISi decreased the viability of PC-3, DU145, 22Rv-1 and LNCaP cells, and significantly increased apoptosis in parallel with the increased cellular ROS content. The efficacy of MEISi was shown to positively correlate with the levels of MEIS1/2/3 proteins and the long term exposure to MEISi elevated MEIS1/2/3 protein content in PCa cells. Our findings suggest that MEISi could be used to target PCa with high MEIS expression in order to reduce PCa viability and growth; however, more research is needed before this can be translated into clinical settings.

Identification of Small Molecules That Enhance the Expansion of Mesenchymal Stem Cells Originating from Bone Marrow

Mesenchymal stem cells (MSCs) have been shown to be promising for regenerative medicines with their immunomodulatory characteristics. They may be obtained from a variety of tissue types, including umbilical cord, adipose tissue, dental tissue, and bone marrow (BM). BM-MSCs are challenging in terms of their ex vivo expansion capability. Thus, we aimed to improve the expansion of BM-MSCs with small molecule treatments. We tested about forty small molecules that are potent quiescence modulators, and determined their efficacy by analysis of cell viability, cell cycle, and apoptosis in BM-MSCs. We also examined gene expression for selected small molecules to explore essential molecular pathways. We observed that treatment with SB203580 increased BM-MSCs expansion up to two fold when used for 5 days. SB203580 decreased the proportion of cells in the G1 phase of the cell cycle and substantially increased the ratio of cells in the S-G2-M phase. Enhanced MSC expansion with SB203580 therapy was associated with the lower expression of CDKIs like p15, p18, p19, p21, p27, and p57. In conclusion, we have developed a new approach to facilitate the expansion of BM-MSCs. These results could enhance autologous and immunomodulation therapy involving BM-MSCs.

Identification of first-in-class plasmodium OTU inhibitors with potent anti-malarial activity

OTU proteases antagonize the cellular defense in the host cells and involve in pathogenesis. Intriguingly, P. falciparum, P. vivax, and P. yoelii have an uncharacterized and highly conserved viral OTU-like proteins. However, their structure, function or inhibitors have not been previously reported. To this end, we have performed structural modeling, small molecule screening, deconjugation assays to characterize and develop first-in-class inhibitors of P. falciparum, P. vivax, and P. yoelii OTU-like proteins. These Plasmodium OTU-like proteins have highly conserved residues in the catalytic and inhibition pockets similar to viral OTU proteins. Plasmodium OTU proteins demonstrated Ubiquitin and ISG15 deconjugation activities as evident by intracellular ubiquitinated protein content analyzed by western blot and flow cytometry. We screened a library of small molecules to determine plasmodium OTU inhibitors with potent anti-malarial activity. Enrichment and correlation studies identified structurally similar molecules. We have identified two small molecules that inhibit P. falciparum, P. vivax, and P. yoelii OTU proteins (IC50 values as low as 30 nM) with potent anti-malarial activity (IC50 of 4.1-6.5 µM). We also established enzyme kinetics, druglikeness, ADME, and QSAR model. MD simulations allowed us to resolve how inhibitors interacted with plasmodium OTU proteins. These findings suggest that targeting malarial OTU-like proteases is a plausible strategy to develop new anti-malarial therapies.

SC1 limits tube formation, branching, migration, expansion and induce apoptosis of endothelial cells

Endothelial cells (ECs) are essential in the growth and progression of the tumor cells by supplying nutrition and angiogenesis factors. Targeting ECs emerged as a major strategy to prevent the growth of tumors. Studies suggest that ERK1/2 signaling is important for endothelial cells, which could be specifically targeted by small molecule SC1. We aimed to study the effects of SC1 treatments on endothelial cell proliferation, angiogenesis, and death. To this end, we performed viability, apoptosis, cell cycle, gene expression, wound closure, tube formation, and western blot analysis in endothelial cells post SC1 treatments. Intriguingly, we found that SC1 has an antiangiogenic effect on endothelial cells, which limits the endothelial cell expansion, tube formation, branching, and migration. The proliferation is especially limited in dose dependent manner by SC1. In addition, we found that SC1 elevates the apoptosis of endothelial cells and associated pathways including BAK1, Stat1, Sox4, and Caspase1. We believe that these findings could contribute to the development of improved therapies based on the SC1 as an attractive candidate for anticancer clinical studies targeted to tumor angiogenesis.

Is It All About Endothelial Dysfunction and Thrombosis Formation? The Secret of COVID-19

The world is in a hard battle against COVID-19. Endothelial cells are among the most critical targets of SARS-CoV-2. Dysfunction of endothelium leads to vascular injury following by coagulopathies and thrombotic conditions in the vital organs increasing the risk of life-threatening events. Growing evidences revealed that endothelial dysfunction and consequent thrombotic conditions are associated with the severity of outcomes. It is not yet fully clear that these devastating sequels originate directly from the virus or a side effect of virus-induced cytokine storm. Due to endothelial dysfunction, plasma levels of some biomarkers are changed and relevant clinical manifestations appear as well. Stabilization of endothelial integrity and supporting its function are among the promising therapeutic strategies. Other than respiratory, COVID-19 could be called a systemic vascular disease and this aspect should be scrutinized in more detail in order to reduce related mortality. In the present investigation, the effects of COVID-19 on endothelial function and thrombosis formation are discussed. In this regard, critical players, laboratory findings, clinical manifestation, and suggestive therapies are presented.

Development of small-molecule-induced fibroblast expansion technologies

Dermal fibroblasts are responsible from the production of extracellular matrix and take role in the closure of skin wounds. Dermal fibroblasts are major cells of origin in the generation of induced pluripotent stem cells (IPSCs) and are historically being used as feeder layer and biofiller in the restorative surgeries. ex vivo expansion of the dermal fibroblasts provides a suitable model to study skin biology and to engineer bioartifical skins. Thus, development of efficient fibroblast expansion technologies gets outmost importance day by day. We sought to identify small molecules that induce ex vivo fibroblast expansion and understand their mechanisms. We analyzed the effect of 35 small molecules, which are expected to target molecular pathways involving cellular quiescence. We have found that small molecules, especially AS1949490 and SKF96365, increase human dermal fibroblast expansion of at least three different fibroblasts. Cell cycle analysis confirms that these small molecules allow cell cycle progression, as evident by increased percentage of cells in S-G₂ -M phase of cell cycle. They led to a lower profile of apoptotic or necrotic fibroblasts. Intriguingly, we have found that identified small molecules could also endogenously induce the expression of IPSC generation, collagen synthesis, and aging-related genes. Identified small molecules may contribute to the induction of collagen synthesis in the biofiller products, the development of fibroblast products with better aging profile, and the improvement of IPSC generation.

COVID-19-driven endothelial damage: complement, HIF-1, and ABL2 are potential pathways of damage and targets for cure

COVID-19 pandemia is a major health emergency causing hundreds of deaths worldwide. The high reported morbidity has been related to hypoxia and inflammation leading to endothelial dysfunction and aberrant coagulation in small and large vessels. This review addresses some of the pathways leading to endothelial derangement, such as complement, HIF-1α, and ABL tyrosine kinases. This review also highlights potential targets for prevention and therapy of COVID-19-related organ damage and discusses the role of marketed drugs, such as eculizumab and imatinib, as suitable candidates for clinical trials.