Indirect Immobilised Jagged-1 Enhances Matrisome Proteins Associated with Osteogenic Differentiation of Human Dental Pulp Stem Cells: A Proteomic Study

The indirect immobilisation of Jagged-1 (Jagged-1) promoted osteogenic differentiation of human dental pulp cells (hDPs). Furthermore, the analysis of the Reactome pathway of RNA sequencing data indicates the upregulated genes involved with the extracellular matrix (ECM). Hence, our objective was to investigate the effects of Jagged-1 on proteomic profiles of human dental pulp stem cells (hDPSC). hDPSCs were cultured on the surface coated with human IgG Fc fragment (hFc) and the surface coated with rhJagged1/Fc recombinant protein-coated surface. Cells were differentiated to the osteogenic lineage using an osteogenic differentiation medium (OM) for 14 days, and cells cultured in a growth medium were used as a control. The protein component of the cultured cells was extracted into the cytosol, membrane, nucleus, and cytoskeletal compartment. Subsequently, the proteomic analysis was performed using liquid chromatography–tandem mass spectrometry (LC-MS). Metascape gene list analysis reported that Jagged-1 stimulated the expression of the membrane trafficking protein (DOP1B), which can indirectly improve osteogenic differentiation. hDPSCs cultured on Jagged-1 surface under OM condition expressed COL27A1, MXRA5, COL7A1, and MMP16, which played an important role in osteogenic differentiation. Furthermore, common matrisome proteins of all cellular components were related to osteogenesis/osteogenic differentiation. Additionally, the gene ontology categorised by the biological process of cytosol, membrane, and cytoskeleton compartments was associated with the biomineralisation process. The gene ontology of different culture conditions in each cellular component showed several unique gene ontologies. Remarkably, the Jagged-1_OM culture condition showed the biological process related to odontogenesis in the membrane compartment. In conclusion, the Jagged-1 induces osteogenic differentiation could, mainly through the regulation of protein in the membrane compartment.     

Hydrolysis of raw hide using proteolytic enzyme extracted from papaya latex

Crude proteolytic enzyme was extracted from papaya latex using two solvents, water and phosphate buffer pH 6. The yield of extracted enzyme using water as a solvent was similar to that using phosphate buffer. Following the solvent extraction, the extracted enzyme was precipitated in 45 wt% saturated ammonium sulfate solution. The yield and activity of precipitated enzyme considerably decreased. Crude proteolytic enzyme extracted using water as an extracting liquid was, therefore, selected to use in gelatin production from raw hide hydrolysis, comparing to the use of commercial papain. The effects of hydrolysis conditions on gelatin recovery and properties of obtained gelatin were investigated. The optimum conditions for the activities of both crude extracted enzyme and commercial papain were at 75 °C and pH 7. At this condition, the highest percentages of gelatin recovery were obtained from raw hide hydrolysis reactions. The gelatin recovery and gel strength of gelatin obtained from crude extracted enzyme and commercial papain hydrolysis were similar. This proved that crude extracted enzyme from papaya latex could be effectively used in gelatin production, instead of the use of commercial papain, with a comparatively low cost.     

Antioxidative activity of Mungoong,an extract paste,from the cephalothorax of white shrimp (Litopenaeus vannamei)

The antioxidative activity of Mungoong, an extract paste, from the cephalothorax of white shrimp (Litopenaeus vannamei) was studied. Extraction media were shown to affect the antioxidative activity and properties of resulting extracts from Mungoong. Distilled water exhibited the highest efficacy in extracting the antioxidants from Mungoong, as evidenced by the highest ABTS (2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) and DPPH (2,2-diphenyl-1-picryl hydrazyl) radical scavenging activity as well as ferric reducing activity power (FRAP), compared with distilled water/ethanol mixture (1:1, 1:2 and 2:1) and ethanol. UV-absorbances at both 280 and 295 nm (A₂₈₀, A₂₉₅), browning intensity (A₄₂₀) and fluorescence intensity were also highest in the extract using distilled water. ABTS and DPPH radical scavenging activity and FRAP of water extract, increased linearly with increasing concentration. Good correlation between ABTS and DPPH radical scavenging activity; DPPH radical scavenging activity and FRAP; ABTS radical scavenging activity and FRAP were observed, suggesting that antioxidants in the extract, possessed the capability of scavenging the radicals together with reducing power. Antioxidants in the water extract from Mungoong showed high stability over the wide pH ranges (2–11) and temperature up to 100 °C, in which the activity of more than 80% remained. MALDI-TOF analysis revealed that water extract contained the peptides having the mass ranges of m/z 400–1000 and 4000–7000.     

Anti-listeria activity of Pediococcus pentosaceus BCC 3772 and application as starter culture for Nham, a traditional fermented pork sausage

Lactic acid bacteria forming bacteriocin active against Listeria monocytogenes were screened for potential use in controlling growth of L. monocytogenes in Nham, a Thai traditional fermented pork sausage. Based on the spot-on-lawn assay, Pediococcus pentosaceus BCC 3772 was found to produce the highest anti-listeria activity. Through a series of chromatographic techniques, Edman N-terminal sequencing and mass spectrometry, this anti-listeria compound showed a complete homology to pediocin PA-1/AcH. Inoculation of P. pentosaceus BCC 3772 in Nham caused a significant decrease of 3.2 log in population of spiked L. monocytogenes within 18-24 h of fermentation, in comparison with the initial count with no significant changes in sensory properties and consumer acceptability on the overall characteristics of the final fermented Nham products. These results indicate that the P. pentosaceus BCC 3772 should be useful as a functional starter culture for control of L. monocytogenes without compromising the unique quality of Nham.     

Characteristics of gelatin from the skins of bigeye snapper, Priacanthus tayenus and Priacanthus macracanthus

Gelatins extracted from the skins containing fine scales of two species of bigeye snapper, Priacanthus tayenus (GT) and Priacanthus macracanthus (GM), were characterised. Both gelatins had the protein as the major component with high content of imino acids (proline & hydroxyproline) (186.29–187.42 mg/g). GT and GM contained calcium at levels of 6.53 and 2.92 g/kg, respectively. Both gelatins contained α1 and α2 chains as the predominant components and some degradation peptides. The absorption bands of both gelatins in Fourier transform infrared (FTIR) spectra were mainly situated in the amide band region (amide I and amide II). GT and GM had a relative solubility greater than 90% in the wide pH ranges (1–10). The bloom strength of GM (254.10 g) was higher than that of GT (227.73 g) (P < 0.05), but was slightly lower than that of commercial bovine gelatin (293.22 g) (P < 0.05). Finer gel structure with smaller strands and voids was observed in GM gel, in comparison with that observed in GT counterpart.     

Proteomics Analysis of Andrographolide-Induced Apoptosis via the Regulation of Tumor Suppressor p53 Proteolysis in Cervical Cancer-Derived Human Papillomavirus 16-Positive Cell Lines

Regardless of the prophylactic vaccine accessibility, persistent infections of high-risk human papillomaviruses (hr-HPVs), recognized as an etiology of cervical cancers, continues to represent a major health problem for the world population. An overexpression of viral early protein 6 (E6) is linked to carcinogenesis. E6 induces anti-apoptosis by degrading tumor suppressor proteins p53 (p53) via E6-E6-associated protein (E6AP)-mediated polyubiquitination. Thus, the restoration of apoptosis by interfering with the E6 function has been proposed as a selective medicinal strategy. This study aimed to determine the activities of andrographolide (Androg) on the disturbance of E6-mediated p53 degradation in cervical cancer cell lines using a proteomic approach. These results demonstrated that Androg could restore the intracellular p53 level, leading to apoptosis-induced cell death in HPV16-positive cervical cancer cell lines, SiHa and CaSki. Mechanistically, the anti-tumor activity of Androg essentially relied on the reduction in host cell proteins, which are associated with ubiquitin-mediated proteolysis pathways, particularly HERC4 and SMURF2. They are gradually suppressed in Androg-treated HPV16-positive cervical cancer cells. Collectively, the restoration of p53 in HPV16-positive cervical cancer cells might be achieved by disruption of E3 ubiquitin ligase activity by Androg, which could be an alternative treatment for HPV-associated epithelial lesions.     

Isolation and identification of antioxidative peptides from hydrolysate of threadfin bream surimi processing byproduct

The objective of this study was to determine the antioxidant activity and possible mode of action of partially purified peptides derived from threadfin bream surimi byproduct. The frame, bone and skin (FBS) byproduct, which was obtained from a deboning process, was hydrolyzed by Virgibacillus sp. SK33 proteinase and fractionated using anion exchange and size exclusion chromatography. Three fractions, i.e., B1, B2 and B3, were obtained, and the amino acid sequences of the peptides in all 3 fractions were determined using LC-MS/MS. Fractions B2 and B3 contained higher amounts of Trp, Met, Cys and Tyr residues than fraction B1. Fraction B3 exhibited high ABTS radical scavenging activity and ferric reducing antioxidant power (FRAP), while metal chelation and hydroxyl radical scavenging ability were principle modes of action of peptides in fraction B2 and B3. In addition, fraction B1 and a synthetic peptide selected from the pooled de novo peptides of fraction B3, FLGSFLYEYSR, had a cellular radical scavenging effect when HepG2 cells were treated with H₂O₂.     

Antioxidant activity and stability of endogenous peptides from farmed hybrid catfish (Clarias macrocephalus × Clarias gariepinus) muscle

The antioxidant activity and stability of endogenous peptides isolated from farmed hybrid catfish (Clarias macrocephalus × Clarias gariepinus) muscle (EPC) were characterised. EPC contained 69 peptides with 8–24 amino acid residues, varying hydrophobic amino acid (HBA) content and distinct sequences. Among the top five, peptides discovered in EPC were ARHSYGMLYCSCPPND, DTQAARKSDDDD, AEFPCGDRRC, AAVTEELFFAGL and LILQRRKFLRMKREKYGFIYKTHL. Histidine (16.33%) and tryptophan (15.66%) were the most common amino acids found in EPC. EPC demonstrated concentration-dependent free radical (DPPH^•/ABTS^•+) and hydroxyl radical (OH^•) scavenging activities, as well as metal chelating ability. The effect of pH, heating temperature and in vitro digestion on EPC's DPPH^• scavenging activity was studied. Lowering the pH and increasing the heating temperature to 90 °C increased the DPPH^• inhibitory activity. However, after in vitro digestion, around 44% of DPPH^• inhibition was reduced. The findings confirmed that farm-raised hybrid catfish muscle contained endogenous peptides with antioxidant properties.