A Novel Antiviral Protein Derived from Oenanthe javanica: Type I Interferon-Dependent Antiviral Signaling and Its Pharmacological Potential.

Pathogenesis-related (PR) proteins produced in plants play a crucial role in self-defense against microbial attacks. Previously, we have identified a novel PR-1-like protein (OPRP) from Oenanthe javanica and examined its pharmacologic relevance and cell signaling in mammalian cells. Purified full-length OPRP protein significantly increased toll-like receptor 4 (TLR4)-dependent expression levels of genes such as inducible nitric oxide synthase (iNOS), tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), and CD80. We also found that small peptides (OPRP2 and OPRP3) designed from OPRP remarkably upregulated myxovirus resistance (Mx1), 2'-5' oligoadenylate sythetase (OAS), and interferon (IFN) α/ß genes in mouse splenocytes as well as human epithelial cells. Notably, OPRP protein distinctively activated STAT1 phosphorylation and ISGF-3γ. Interestingly, OPRP2 and OPRP3 were internalized to the cytoplasm and triggered dimerization of STAT1/STAT2, followed by upregulation of type I IFN-dependent antiviral cytokines. Moreover, OPRP1 successfully inhibited viral (Pseudo SARS-CoV-2) entry into host cells. Taken together, we conclude that OPRP and its small peptides (OPRP1 to 3) present a new therapeutic intervention for modulating innate immune activity through type I IFN-dependent antiviral signaling and a new therapeutic approach that drives an antiviral state in non-immune cells by producing antiviral cytokines.

Identification, protein antiglycation, antioxidant, antiproliferative, and molecular docking of novel bioactive peptides produced from hydrolysis of Lens culinaris.

Bioactive peptides produced from natural sources are considered as strategic target for drug discovery. Hyperglycemia caused protein glycation alters the structure of many tissues that impairs their functions and lead complications diseases in human body. This study investigated the bioactive peptides produced from red and brown Lens culinaris that might inhibit protein glycation to prevent diabetic complications. In this study, red and brown Lens culinaris protein hydrolysates were prepared by tryptic digestion, using an enzyme/substrate ratio of 1:20 (g/g), at 37°C, 12 hr then peptide fractions <3 kDa were filtered by using ultrafiltration membranes. Protective ability against protein glycation, DPPH radical scavenging, and anti-proliferative activities (on HepG2, MCF-7, and PC3 cell lines) of peptide fractions were assayed in vitro. Results showed that glycation was inhibited by peptides from 28.1% to 68.3% in different test model. PC3 cell line was more sensitive to the peptides which showed strong anticancer activity with lower IC50 (0.96 mg/ml). Peptide fractions were sequenced by HPLC-MS-MS. Twenty eight novel peptides sequences was identified. In silico study, two peptides could be developed as a potential bioactive peptides exhibited antiglycation, antioxidant, and antiproliferative activities. PRACTICAL APPLICATIONS: Peptides are becoming an emerging source of medications with the development of new technologies. We have selected Lens Culinaris as one of the rich sources of proteins to explore novel bioactive peptides encapsulated in its seeds. Peptides fractions demonstrated protective ability against protein glycation, strong antioxidant potential, and promising antiproliferative activity. We have identified 28 novel peptides and molecular docking study revealed that some peptides showed strong binding potential to insulin receptor and ACE. Thus, these peptides might be used to manage diabetes complication as well as COVID-19 disease due to their interaction with ACE. However, those peptides needs to be further studied as a potential new drug.