Inhibition of bleomycin-induced pulmonary fibrosis in SD rats by sea cucumber peptides.

BACKGROUND: Pulmonary fibrosis (PF) is the terminal manifestation of a type of pulmonary disease, which seriously affects the respiratory function of the body, and with no effective cure for treatment. This study evaluated the effect of sea cucumber peptides (SCP) on bleomycin-induced SD rat PF. RESULTS: SCP can inhibit the PF induced by bleomycin. PF and SCP did not affect the food intake of rats, but PF reduced the body weight of rats, and SCP could improve the weight loss. SCP reduced lung index in PF rats in a dose-dependent manner. SCP significantly reduced IL-1ß, IL-6, TNF-α, α-SMA and VIM expression levels in lung tissue (P < 0.05), significantly decreased TGF-ß1 expression level in serum (P < 0.01) and the LSCP group and MSCP group had better inhibitory effects on PF than the HSCP group. Histomorphological results showed that SCP could ameliorate the structural damage of lung tissue, alveolar wall rupture, inflammatory cell infiltration, fibroblast proliferation and deposition of intercellular matrix and collagen fibers caused by PF. The improvement effect of the MSCP group was the most noteworthy in histomorphology. Metabolomics results showed that SCP significantly downregulated catechol, N-acetyl-l-histidine, acetylcarnitine, stearoylcarnitine, d-mannose, l-threonine, l-alanine, glycine, 3-guanidinopropionic acid, prostaglandin D2 and embelic acid d-(-)-ß-hydroxybutyric acid expression levels in lung tissue. CONCLUSION: SCP ameliorate bleomycin-induced SD rat PF. KEGG pathway analysis proved that SCP intervened in PF mainly via the lysosome pathway, with d-mannose as the key factor. © 2023 Society of Chemical Industry.

Hypoglycemic Activity of Self-Assembled Gellan Gum-Soybean Isolate Composite Hydrogel-Embedded Active Substance-Saponin.

In order to avoid hemolysis caused by direct dietary of kidney tea saponin, complex gels based on gellan gum (GG) and soybean isolate protein (SPI) loaded with saponin were created in the present study by using a self-assembly technique. Studies were conducted on the rheological characteristics, encapsulation effectiveness, molecular structure, microstructure, and hypoglycemic activity of GG/SPI-saponin gels. Increasing the concentration of SPI helped to enhance the strength and energy storage modulus (G') of the gels, and the incorporation of high acylated saponin allowed the whole gel to undergo sol-gel interconversion. The encapsulation efficiency showed that GG/SPI-saponin was 84.52 ± 0.78% for saponin. Microstructural analysis results suggested that GG and SPI were bound by hydrogen bonds. The in vitro digestion results also indicated that saponin could be well retained in the stomach and subsequently released slowly in the intestine. In addition, the in vitro hypoglycemic activity results showed that the IC50 of encapsulated saponin against α-glucosidase and α-amylase were at 2.4790 mg/mL and 1.4317 mg/mL, respectively, and may be used to replace acarbose for hypoglycemia.