Nitric Oxide-Scavenging, Anti-Migration Effects, and Glycosylation Changes after Hemin Treatment of Human Triple-Negative Breast Cancer Cells: A Mechanistic Study.

The enhanced expression of nitric oxide (•NO) synthase predicts triple-negative breast cancer outcome and its resistance to different therapeutics. Our earlier work demonstrated the efficiency of hemin to scavenge the intra- and extracellular •NO, proposing its potency as a therapeutic agent for inhibiting cancer cell migration. In continuation, the present work evaluates the effects of •NO on the migration of MDA-MB-231 cells and how hemin modulates the accompanied cellular behavior, focusing on the corresponding expression of cellular glycoproteins, migration-associated markers, and mitochondrial functions. We demonstrated for the first time that while •NO induced cell migration, hemin contradicted that by •NO-scavenging. This was in combination with modulation of the •NO-enhanced glycosylation patterns of cellular proteins with inhibition of the expression of specific proteins involved in the epithelial-mesenchymal transition. These effects were in conjunction with changes in the mitochondrial functions related to both •NO, hemin, and its nitrosylated product. Together, these results suggest that hemin can be employed as a potential anti-migrating agent targeting •NO-scavenging and regulating the expression of migration-associated proteins.

Glucose-Responsive Fibrin Hydrogel-Based Multimodal Nucleic Acid Delivery System.

Nucleic acid therapy has emerged as a potential alternative for promoting wound healing by gene expression modification. On the other hand, protecting the nucleic acid payload from degradation, efficient bioresponsive delivery and effective transfection into cells remain challenging. A glucose-responsive gene delivery system for treating diabetic wounds would be advantageous as it would be responsive to the underlying pathology giving a regulated payload delivery with fewer side effects. Herein a GOx-based glucose-responsive delivery system is designed based on fibrin-coated polymeric microcapsules (FCPMC) using the layer-by-layer (LbL) approach that simultaneously delivers two nucleic acids in diabetic wounds. The designed FCPMC displays an ability to effectively load many nucleic acids in polyplexes and release it over a prolonged period with no cytotoxic effects seen in in vitro studies. Furthermore, the developed system does not show any undesired effects in vivo. When applied to wounds in genetically diabetic db/db mice, the fabricated system on its own improves reepithelialization and angiogenesis while decreasing inflammation. Also, key proteins involved in the wound healing process, i.e., Actn2, MYBPC1, and desmin, are upregulated in the glucose-responsive fibrin hydrogel (GRFHG) treated group of animals. In conclusion, the fabricated hydrogel promotes wound healing. Furthermore, the system may be encapsulated with various therapeutic nucleic acids that aid wound healing.

Metabolic reprogramming and membrane glycan remodeling as potential drivers of zebrafish heart regeneration.

The ability of the zebrafish heart to regenerate following injury makes it a valuable model to deduce why this capability in mammals is limited to early neonatal stages. Although metabolic reprogramming and glycosylation remodeling have emerged as key aspects in many biological processes, how they may trigger a cardiac regenerative response in zebrafish is still a crucial question. Here, by using an up-to-date panel of transcriptomic, proteomic and glycomic approaches, we identify a metabolic switch from mitochondrial oxidative phosphorylation to glycolysis associated with membrane glycosylation remodeling during heart regeneration. Importantly, we establish the N- and O-linked glycan structural repertoire of the regenerating zebrafish heart, and link alterations in both sialylation and high mannose structures across the phases of regeneration. Our results show that metabolic reprogramming and glycan structural remodeling are potential drivers of tissue regeneration after cardiac injury, providing the biological rationale to develop novel therapeutics to elicit heart regeneration in mammals.