Isolation of Antimicrobial Peptides from Fritillaria pallidiflora

Total alkaloids of bulbus of Fritillaria cirrhosa alleviate bleomycin-induced inflammation and pulmonary fibrosis in rats by inhibiting TGF-β and NF-κB signaling pathway

Background

Bulbus of Fritillaria cirrhosa is a medicinal and edible plant that has the functions of clearing away heat and moisturizing the lungs, resolving phlegm, and relieving coughs. Its ethanol extract has been proven to have a therapeutic effect on lung diseases. Pulmonary fibrosis is a respiratory disease that forms scars in lung tissue, leading to severe respiratory problems. However, the therapeutic effect of total alkaloids of bulbus of Fritillaria cirrhosa (BFC-TA) on pulmonary fibrosis has not been confirmed.

Objective

This study aimed to investigate the therapeutic effect of total alkaloids of Fritillaria cirrhosa on pulmonary fibrosis rat model and explore its potential mechanism.

Design

The total alkaloids in the bulbus of Fritillaria cirrhosa were purified using cation exchange resin. The alkaloids contained in the BFC-TA were identified, and the concentration of alkaloids was determined by High Performance Liquid Chromatography-Diode Array Detector-Evaporative Light Scattering Detector (HPLC-DAD-ELSD). Bleomycin (BLM) (5.0 mg/kg) was instilled into the trachea of 60 rats to establish a pulmonary fibrosis model. After 7 days, BFC-TA (34.2, 68.4, and 136.8 mg/kg) was administered continuously for 21 days. During this period, the body weight changes of the rats were measured, the levels of hydroxyproline (HYP) and inflammatory factors were measured in the collected serum, and the histological analysis of the lung tissue was performed by staining technology. Western blotting and quantitative Polymerase Chain Reaction (qPCR) were used to assess the protein and gene composition of inflammation and transforming growth factor-β (TGF-β) signaling pathways.

Results

Nine main components (Peimisine, Imperialine-3-β-D-glucoside, Yibeinoside A, Imperialine, Peiminine, Isopeimine, Hupehenine, Delavinone, Ebeiedinone) were determined by HPLC-DAD-ELSD, and the contents of Peimisine, Imperialine-3-β-D-glucoside and Imperialine were determined. BFC-TA (34.2, 68.4, and 136.8 mg/kg) reduced the levels of pro-inflammatory factors, increased the levels of anti-inflammatory factors, dose-dependently improved the morphology of lung tissue. And during epithelial-mesenchymal transition process, BFC-TA dose-dependently reduced the expression of E-cadherin, dose-dependently increased the expression of Fibronectin. In addition, Western blot analysis and qPCR results showed that inhibiting NF-κB and TGF-β-related signaling pathways effectively slowed down the occurrence of BLM-induced pulmonary fibrosis in rats. And the therapeutic effect of BFC-TA (136.8 mg/kg) is better than that of pirfenidon (PFD) (150 mg/kg).

Conclusion

BFC-TA effectively alleviates the progression of the BLM-induced pulmonary fibrosis rat model by regulating the inflammatory response in the lungs and the expression of the TGF-β signaling pathway.

Unusual ring B-seco isosteroidal alkaloid, yibeiglycoalkaloids A-E from Fritillaria pallidiflora schrenk

Five previously undescribed steroidal glycoalkaloids(SGAs)and a rare ring B-seco isosteroidal alkaloid, were isolated from Fritillaria pallidiflora Schrenk, along with six known alkaloids. The structures of these alkaloids were established by comprehensive analyses of the 1D, 2D-NMR and HR-ESI-MS data. Configurations of sugar moieties were resolved by chemical derivations. The isolated compounds showed nitric oxide (NO) inhibitory activities in lipopolysaccharide (LPS) induced RAW264.7 cells, and yibeinone exhibited the strongest inhibitory effects among them. This study revealed that the alkaloids from F. pallidiflora might have significant anti-inflammatory potentials.

Application of Analytical Technologies in the Discrimination and Authentication of Herbs from Fritillaria: A Review

Medicinal plants of Fritillaria are widely distributed in numerous countries around the world and possess excellent antitussive and expectorant effects. In particular, Fritillariae Bulbus (FB) as a precious traditional medicine has thousands of years of medical history in China. Herbs of Fritillaria have a high market value and demand while limited by harsh growing circumstances and scarce wild resources. As a consequence, fraudulent behaviors are regularly engaged by the unscrupulous merchants in an attempt to reap greater profits. It is of an urgent need to evaluate the quality of Fritillaria herbs and their products using various analytical instruments and techniques. This review has scrutinized approximately 160 articles from 1995 to 2022 published on the investigation of Fritillaria herbs and related herbal products. The botanical classification of genus Fritillaria, types of counterfeits, technologies applied for differentiating Fritillaria species were comprehensively summarized and discussed in the current review. Molecular and chromatographic identification were the dominant technologies in the authentication of Fritillaria herbs. Additionally, we brought some potential and promising technologies and analytical strategies into attention, which are worthy attempting in the future researches. This review could conduce to excellent reference value for further investigations of the authenticity assessment of Fritillaria species.

Isolation and Evaluation of Bioactive Protein and Peptide from Domestic Animals' Bone Marrow

In this work, proteins and peptides were isolated from four kinds of animal bone marrow and characterized by sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDS-PAGE), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and liquid chromatography-mass spectrometry (LC/MS). The antimicrobial and antioxidant activity of these proteins were investigated in vitro. The nutritional value was evaluated by analyzing their free amino acid composition. The results indicates that all of the extracts appeared two bands at SDS-PAGE, the peptide band at 4.1⁻10 kDa and protein band at 66 kDa, these data are consistent with LC/MS results. FT-IR analysis showed that the secondary structure of protein mainly consists of α-helix. SEM micrographs revealed that the fractions have different morphological characteristics. Horse bone marrow protein (HBMP) showed the highest antioxidant activity to DPPH free radical, IC₅₀ value was 0.573 mg/mL. Most of the obtained fractions showed antimicrobial activities towards Escherichiacoli (EC) and Candida albicans (CA). Total free amino acid content ranged between 5.15⁻49.60 mg/g, and among them, HBMP displayed the highest abundance, 49.7 mg/g, which amino acid composition ratio approached the Food and Agriculture Organization/World Health Organization (FAO/WHO) ideal amino acid pattern recommendation. This study provides fundamental knowledge and a basic study method for the research into and development of animal bone marrow proteins and peptides as functional food and drug resources.