Immobilization of modular peptides on graphene cocktail for differentiation of human mesenchymal stem cells to hepatic-like cells.

In this study, two novel biomimetic modular peptide motifs based on the alpha-2 subunit of type IV collagen (CO4A2) were designed and immobilized on a graphene platform to imitate integrin and heparan sulfate- (HS-) binding proteins. The in silico study was used to design 9-mer K[KGDRGD]AG and 10-mer KK[SGDRGD]AG for testing designed Integrin-Binding Peptide (dIBP) and HS-Binding Peptide (dHBP). The virtual docking technique was used to optimize the peptide motifs and their relevant receptors. Molecular dynamic (MD) simulation was used to evaluate the stability of peptide-receptor complexes. The effect of the platform on the differentiation of human mesenchymal stem cells (hMSCs) to hepatic-like cells (HLCs) was evaluated. After differentiation, some hepatic cells' molecular markers such as albumin, AFP, CK-18, and CK-19 were successfully followed. Graphene-heparan sulfate binding peptide (G-HSBP) enhances the mature hepatic markers' expression instead of control (p ≤ 0.05). The pathological study showed that the designed platform is safe, and no adverse effects were seen till 21 days after implantation.

The trend in application of omics in type 2 diabetes researches; A bibliometric study.

AIMS: Due to the importance of omics approaches in diabetes diagnosis, we were assumed to study the scientific activities on omics and type 2 diabetes worldwide. METHOD: Bibliometric approach was utilized to evaluate the documents on proteomics, lipidomics, and metabolomics in patients with type 2 diabetes in the Scopus database from the beginning to 2020. The articles were screened by two reviewers and the number of publications and citations on omics and type 2 diabetes, top-ranked journals, top-cited articles, country co-contributions, co-authorships, author keywords, and terms were analyzed. RESULTS: The scientific publications in this field consisted of 551 original articles, of which the USA shares the most percent, followed by China and Germany. The frequent keywords showed that the following hotspots were of interest: "Metabolomics, proteomics, and lipidomics as biomarkers for diabetes", "Omics and diabetic nephropathy", "The application of omics in obesity, insulin resistance, and type 2 diabetes". CONCLUSION: This study showed an increasing trend in applying omics in type 2 diabetes researches and determined the leading producers in this field. Besides, the research hotspots and the main subjects of documents were provided for future research and policy decision-making.

Cell attachment evaluation of the immobilized bioactive peptide on a nanographene oxide composite.

The immobilization of bioactive peptides as key molecules in numerous biological and physiological functions holds promise for designing advanced biomaterials. Graphene and its derivatives, having unique physicochemical properties, have brought considerable attention in the life sciences. In this regard, the chemical manipulation of the graphene surface with bioactive peptides opens a new horizon to design bioactive materials for a variety of future nanobiotechnologies. In this study, the first straightforward strategy for the covalent immobilization of the cell-adhesion peptide onto the graphene surface based on the Ugi four-component assembly process (Ugi 4-CAP) will be presented. The modified adhesion motif peptide, as an amine component in the presence of formaldehyde, cyclohexylisocyanide and carboxylated-graphene (G-COOH), was adopted in a four component reaction to fabricate a peptide-graphene (Peptide-G) biomaterial in water as a green solvent at an ambient temperature. The amino functional groups corresponded to the modified adhesion motif peptide and were immobilized onto the graphene sheets, which were quantified by the Kaiser test. The sheets were characterized by further analyses with FT-IR, AFM, UV-vis, Raman and thermogravimetric analyses. The Peptide-G biomaterial showed excellent biocompatibility. In addition, the Peptide-G treated surface, due to the presence of RGD on the surface of the graphene, significantly accelerated the proliferation of human mesenchymal stem cells (hMSCs) at a better rate regarding the tissue plate.