Aflatoxin B1 contamination reduces the saponins content and anti-osteoporosis efficacy of the traditional medicine Radix Dipsaci

AUTHORS

Shuqin Lu, Qingsong Yuan, Lulu Wang, Dapeng Su, Min Hu, Lanping Guo, Chuanzhi Kang, Tao Zhou, Jinqiang Zhang

ABSTRACT

Ethnopharmacological relevance

The Radix Dipsaci, a traditional Chinese medicine with a history spanning over 2000 years in China, is widely recognized for its hepatorenal tonic properties, musculoskeletal fortifying effects, fracture healing capabilities, and its frequent application in the treatment of osteoporosis. Like many traditional Chinese herbal medicines, preparations from Radix Dipsaci are at risk of contamination by harmful mycotoxins such as aflatoxin B1.

Aims of the study

This study aims to evaluate the impact of aflatoxin B1 contamination on Radix Dipsaci in terms of changes in quality, efficacy of anti-osteoporosis and hepatorenal toxicity.

Materials and methods

The contamination rates and levels of major mycotoxins were determined in 45 batches of Radix Dipsaci samples using UPLC-MS/MS analysis. The total saponin content and the levels of akebia saponin D in Radix Dipsaci and its decoctions were evaluated through high-performance liquid chromatography (HPLC) analysis. Differences in secondary metabolites between samples without any mycotoxin contamination (N-RD) and those contaminated solely by aflatoxin B1 (AFB1-RD) were compared using metabolomics sequencing and analysis. The anti-osteoporotic efficacy of Radix Dipsaci contaminated with aflatoxin B1 was assessed in a murine model of retinoic acid-induced osteoporosis by quantifying bone mineral content and bone mineral density using dual-energy X-ray absorptiometry. Additionally, the hepatorenal toxicity of Radix Dipsaci contaminated with aflatoxin B1 was evaluated using hematoxylin-eosin staining and enzyme-linked immunosorbent assay (ELISA).

Results

The results indicated that aflatoxin B1 (AFB1) was the most frequently detected mycotoxin, found in 37.7% of the Radix Dipsaci samples. AFB1 contamination significantly altered the secondary metabolites of Radix Dipsaci. Specifically, there was a notable decrease in the levels of total saponins and akebia saponin D in the AFB1-contaminated samples, which exhibited a negative correlation with the levels of AFB1 contamination. However, the administration of a water decoction from AFB1-contaminated Radix Dipsaci did not result in significant improvements in bone mineral density, bone mineral salt content, the trabecular number, trabecular area, proportion of trabecular bone volume/tissue volume and trabecular separation in an osteoporosis mouse model. Additionally, we observed that approximately 16.04% of AFB1 could migrate from the raw herbs into the decoction, leading to hepatocyte and kidney cell damage, as well as increased levels of the oxidative stress molecule malondialdehyde and pro-inflammatory cytokines in the liver and kidney tissues of the osteoporosis model mice.

Conclusion

In summary, Radix Dipsaci is highly susceptible to mycotoxin contamination, particularly aflatoxin B1. The contamination of Radix Dipsaci with AFB1 not only impacts their saponin content and anti-osteoporosis effect but also induces hepatotoxicity and nephrotoxicity.

Mechanism of Pingyang Jiangya Formula in treating hypertension based on network pharmacology and in vivo study

AUTHORS

Liu Deguo, Li Zirong, Chen Qihua, Wang Yuhong, Xiao Changjiang

ABSTRACT

Objective

This study aimed to analyze the mechanism of action of the Pingyang Jiangya Formula (平阳降压方, PYJYF) in treating hypertension, based on network pharmacology, and to verify the subsequent predictions through animal experiments.

Methods

The active components and related target genes of PYJYF were screened using the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), Bioinformatics Analysis Tool for Molecular Mechanism of Traditional Chinese Medicine (BATMAN-TCM), Encyclopedia of Traditional Chinese Medicine (ETCM), and DrugBank databases and available literature. The hypertension target genes were screened based on Therapeutic Target Database (TTD), GeneCards, Online Mendelian Inheritance in Man (OMIM), UniProt, and relevant literature. The component-disease-target network intersection target genes were inputted into the STRING database, and the key target genes were selected according to the degree algorithm. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to explore the multitarget mechanism of action and molecular regulatory network of PYJYF in the treatment of hypertension. To verify this prediction, we used PYJYF to intervene in spontaneously hypertensive rats (SHRs) and Wistar–Kyoto rats (WKY) as normal control, and the noninvasive tail artery manometry method was used to measure systolic blood pressure (SBP) in the rat tail before PYJYF intervention. After drug intervention, the SBP of each group rats were measured and compared every week. Enzyme-linked immunosorbent assay (ELISA) was used to test plasma renin, angiotensin II (Ang II), and aldosterone (Ald) levels, and hematoxylin-eosin (HE) staining was used to observe pathological damage to the renal vessels in each group of rats. Western blot and reverse transcription real-time quantitative PCR (RT-PCR) were used to detect the protein and mRNA expression levels of PI3K, AKT1, BAX, and Bcl-2, respectively.

Results

A total of 4 123 hypertension targets were obtained from related databases. From the TCMSP and chemical databases, 78 active components of PYJYF and the corresponding 401 drug targets were retrieved. Data analysis revealed that 208 drug targets directly interacted with the hypertension targets in PYJYF. The 10 targets most closely related to hypertension target proteins in PYJYF were directly retrieved from relevant databases. GO analysis revealed that 10 direct target proteins were involved in all aspects of the antihypertensive effects of PYJYF, as well as molecular biological processes, such as the regulation of blood pressure, renin-angiotensin-aldosterone system (RAAS), angiotensin-mediated ligand reactions, and biological stimulation of cardiomyocyte apoptosis. KEGG pathway enrichment analysis revealed that PYJYF directly affected 20 signaling pathways associated with hypertension. In animal experiments, PYJYF reduced the protein and mRNA levels of PI3K, Akt, and Bax and upregulated the expression of the protein and mRNA levels of Bcl-2, reduced plasma renin, Ang II, and Ald levels, improved the hyperactivity of RAAS, and significantly reduced SBP in SHRs.

Conclusion

PYJYF is effective for hypertension therapy that acts through multiple compounds and targets. The possible underlying molecular mechanism includes regulating the PI3K/Akt signaling pathway to suppress RAAS, increasing the ratio of Bcl-2/Bax proteins, and inhibiting apoptosis, thereby mediating the repair of renal and renal vascular damage caused by hypertension. These findings warrant further research for use in clinical settings.