Abstract: A synthetic peptide sp4 has an amino acid sequence shown in SEQ ID NO: 1. As the sole effective ingredient in the antitumor efficacy test, it has a significant inhibitory effect on both the tumor volume and tumor weight of human osteosarcoma MG-63 in nude mice and has a significant dose-effect and time-effect relationship. There is no difference between the relative tumor growth rate T/C (%) of sp4 and that of the positive control group of Paclitaxel. The safety of sp4 is that its maximal tolerated dose for intravenous administration is 700 mg/kgBW. Sp4 has clear targets of pharmacological effects, while having efficacy in vivo, it also has an inhibitory effect on tumor telomerase, has an arrest on G1 phase of the tumor cell cycle, and inhibits the high expressions of tumor PD-L1 and CD47. The present disclosure relates to multiple uses of sp4, especially in the preparation of a class of antitumor drugs.

Abstract: A synthetic peptide brap can be used in preparing an anti-inflammatory drug for COVID-19. The amino acid sequence of a synthetic peptide brap is as shown in SEQ ID No: 1. The synthetic bradykinin receptor antagonism peptide (brap) has significant target-docking and inhibiting effects on G-protein-coupled bradykinin B1 and B2 receptors. The intranasal administration of brap has local effects on allergic nasal inflammation, and has systemic pharmacodynamic effect on pulmonary leakage, lung injury and LPS-induced cytokine storm. The intravenous injection of brap has an obvious inhibiting effect on the excessive inflammation, oxidative stress response and serious lung injury emerging in LPS-induced mice; and has an obvious inhibiting effect on the excessive release of proinflammatory factors IL-6 and TNF-?, overexpression of IL-6 mRNA, and massive generation of reactive oxygen species (ROS) in the LPS-induced inflammatory factor storm.