Search Results (4)

Synthetic deer antler peptides (TSKYR, TSK, and YR) stimulate the proliferation of human chondrocytes and osteoblasts and increase the chondrocyte content of collagen and glycosamino-glycan in vitro. This study investigated the peptide mixture’s pain relief and chondroprotective effect in a rat model of collagenase-induced osteoarthritis. Thirty-six adult male Sprague–Dawley rats were divided into three groups: control (saline), positive control (hyaluronic acid), and ex-perimental (peptides). Intra-articular collagenase injections were administered on days 1 and 4 to induce osteoarthritis in the left knees of the rats. Two injections of saline, hyaluronic acid, or the peptides were injected into the same knees of each corresponding group at the beginning of week one and two, respectively. Joint swelling, arthritic pain, and histopathological changes were evaluated. Injection of the peptides significantly reduced arthritic pain compared to the control group, as evidenced by the closer-to-normal weight-bearing and paw withdrawal threshold test results. Histological analyses showed reduced cartilage matrix loss and improved total cartilage degeneration score in the experimental versus the control group. Our findings suggest that intra-articular injection of synthetic deer antler peptides is a promising treatment for osteoarthritis. Full article

Cruor, the main component responsible for the red color of mammalian blood, contains 90% haemoglobin, a protein considered to be a rich source of bioactive peptides. The aim of the present study is to assess the potential of human hemoglobin as a source of bioactive peptides, compared with bovine hemoglobin, which has been extensively studied in recent years. More specifically, the study focused on the α137–141 fragment of bovine haemoglobin (TSKYR), a small (653 Da) hydrophilic antimicrobial peptide. In this work, the potential of human hemoglobin to contain bioactive peptides was first investigated in silico in comparison with bovine hemoglobin-derived peptides using bioinformatics tools. The blast results showed a high identity, 88% and 85% respectively, indicating a high similarity between the α and β chains. Peptide Cutter software was used to predict cleavage sites during peptide hydrolysis, revealing major conservation in the number and location of cleavage sites between the two species, while highlighting some differences. Some peptides were conserved, notably our target peptide (TSKYR), while others were specific to each species. Secondly, the two types of hemoglobin were subjected to similar enzymatic hydrolysis conditions (23 °C, pH 3.5), which showed that the hydrolysis of human hemoglobin followed the same reaction mechanism as the hydrolysis of bovine hemoglobin, the ‘zipper’ mechanism. Concerning the peptide of interest, α137–141, the RP-UPLC analyses showed that its identification was not affected by the increase in the initial substrate concentration. Its production was rapid, with more than 60% of the total α137–141 peptide production achieved in just 30 min of hydrolysis, reaching peak production at 3 h. Furthermore, increasing the substrate concentration from 1% to 10% (w/v) resulted in a proportional increase in α137–141 production, with a maximum concentration reaching 687.98 ± 75.77 mg·L⁻¹, approximately ten-fold higher than that obtained with a 1% (w/v) concentration. Finally, the results of the UPLC-MS/MS analysis revealed the identification of 217 unique peptides in bovine hemoglobin hydrolysate and 189 unique peptides in human hemoglobin hydrolysate. Of these, 57 peptides were strictly common to both species. This revealed the presence of several bioactive peptides in both cattle and humans. Although some had been known previously, new bioactive peptides were discovered in human hemoglobin, such as four antibacterial peptides (α37–46 PTTKTYFPHF, α36–45 FPTTKTYFPH, α137–141 TSKYR, and α133–141 STVLTSKYR), three opioid peptides (α137–141 TSKYR,β31–40 LVVYPWTQRF,β32–40, VVYPWTQRF), an ACE inhibitor (β129–135 KVVAGVA), an anticancer agent (β33–39 VVYPWTQ), and an antioxidant (α137–141 TSKYR). To the best of our knowledge, these peptides have never been found in human hemoglobin before. Full article

Tortoiseshell and deer antler gelatin has been used to treat bone diseases in Chinese society. A pepsin-digested gelatin peptide with osteoblast-proliferation-stimulating properties was identified via LC-MS/MS. The resulting pentapeptide, TSKYR, was presumably subjected to further degradation into TSKY, TSK, and YR fragments in the small intestine. The above four peptides were chemically synthesized. Treatment of tripeptide TSK can lead to a significant 30- and 50-fold increase in the mineralized nodule area and density in osteoblast cells and a 47.5% increase in the number of chondrocyte cells. The calcium content in tortoiseshell was relatively higher than in human soft tissue. The synergistic effects of calcium ions and the peptides were observed for changes in osteoblast proliferation and differentiation. Moreover, these peptides can enhance the expression of RUNX2, OCN, FGFR2, and FRFR3 genes in osteoblasts, and aggrecan and collagen type II in chondrocyte (patent pending). Full article

Neokyotorphin (α137-141) is recognized as an antimicrobial peptide and a natural meat preservative. It is produced by conventional enzymatic hydrolysis of bovine hemoglobin, a major component of cruor, a by-product of slaughterhouses. However, during conventional hydrolysis, chemical agents are necessary to adjust and regulate the pH of the protein solution and the mineral salt content of the final hydrolysate is consequently high. To produce this peptide of interest without chemical agents and with a low salt concentration, electrodialysis with bipolar membrane (EDBM), an electromembrane process recognized as a green process, with two different membrane configurations (cationic (MCP) and anionic (AEM) membranes) was investigated. Hydrolysis in EDBM showed the same enzymatic mechanism, “Zipper”, and allowed the generation of α137-141 in the same concentration as observed in conventional hydrolysis (control). EDBM-MCP allowed the production of hydrolysates containing a low concentration of mineral salts but with fouling formation on MCP, while EDBM-AEM allowed the production of hydrolysates without fouling but with a similar salt concentration than the control. To the best of our knowledge, this was the first time that EDBM was demonstrated as a feasible and innovative technology to produce peptide hydrolysates from enzymatic hydrolysis. Full article