Optimization of IL-1RA structure to achieve a smaller protein with a higher affinity to its receptor

DAP1-2: a synthetic peptide targeting IL-1R1 receptor effectively suppresses IL-1β in vitro

The pathological manifestation of the inflammatory process primarily stems from the heightened release of pro-inflammatory cytokines, with IL-1β standing out as a pivotal cytokine. The excessive presence of IL-1β disrupts immune signaling, thereby assuming a pathogenic and exacerbating role in the pathophysiology of numerous inflammatory diseases. Regulating IL-1β levels becomes crucial, and the IL-1Ra molecule serves this purpose by binding to the IL-1R1 receptor, thereby impeding the binding of IL-1β. Several pharmaceuticals have entered the market, aiming to neutralize IL-1β's biological function through diverse mechanisms. However, the existing IL-1β inhibitors are recombinant proteins, characterized by a high production cost and limited stability. Therefore, this study aimed to predict a peptide, named DAP1-2, based on the IL-1Ra molecule. DAP1-2 was designed to attenuate responses triggered by IL-1β by blocking the IL-1R1 receptor. The selection of amino acids from the IL-1Ra molecule (PDB: I1RA) that interact with the three domains of the IL-1R1 receptor was performed using Swiss PDB Viewer. After prediction, chemical synthesis was made using the Fmoc-Synthesis technique. The efficacy of DAP1-2 was assessed using RAW 264.7 cells, which were exposed to LPS (5 μg/mL) for 24 h to induce IL-1β expression and treated with the peptides in different concentrations. IL-1β levels were assessed using ELISA, and the gene expression of IL-1β was measured by RT-qPCR, additionally to the viability test. Results revealed a significant reduction in IL-1β levels and gene expression in cells stimulated by LPS and treated with DAP1-2 in different concentrations. Furthermore, the MTT assay confirmed the nontoxic nature of the peptides on the cell lineage. This alternative approach shows promise as an IL-1 inhibitor, due to the stability, ease of production, and cost-effectiveness provided by the use of synthetic peptides.

Theroleofinterleukin-1familyinfibroticdiseases

Fibrosis refers to the phenomenon that fibrous connective tissues are increased and parenchymal cells are decreased in organs or tissues such as lung, heart, liver, kidney, skin and so on. It usually occurs at the late stage of repair of chronic or recurrent tissue damage. Fibrotic disease is the main factor for the morbidity and mortality of all tissues and organ systems. Long-term fibrosis can lead to organ and tissue dysfunction and even failure. Interleukin -1 family cytokines are a series of classical inflammatory factors and involved in the occurrence and development process of multiple fibrotic diseases, its biological function, relationship with diseases and application are more and more favored by scientists from various countries. So far, 11 cytokines and 10 receptors of IL-1 family have been identified. In this paper, the cytokines, receptors, signaling pathways and biological functions of IL-1 family are summarized, and the correlation with fibrosis diseases is analyzed.

Research progress on the mechanism of beta-cell apoptosis in type 2 diabetes mellitus

Type 2 diabetes mellitus(T2DM) is regarded as one of the most severe chronic metabolic diseases worldwide, which poses a great threat to human safety and health. The main feature of T2DM is the deterioration of pancreatic beta-cell function. More and more studies have shown that the decline of pancreatic beta-cell function in T2DM can be attributable to beta-cell apoptosis, but the exact mechanisms of beta-cell apoptosis in T2DM are not yet fully clarified. Therefore, in this review, we will focus on the current status and progress of research on the mechanism of pancreatic beta-cell apoptosis in T2DM, to provide new ideas for T2DM treatment strategies.