Prophylactic vitamin C supplementation regulates DNA demethylation to protect against cisplatin-induced acute kidney injury in mice.

Cisplatin-induced acute kidney injury (AKI) restricts the use of cisplatin as a first-line chemotherapeutic agent. Our previous study showed that prophylactic vitamin C supplementation may act as an epigenetic modulator in alleviating cisplatin-induced AKI in mice. However, the targets of vitamin C and the mechanisms underlying the epigenetics changes remain largely unknown. Herein, whole-genome bisulfite sequencing and bulk RNA sequencing were performed on the kidney tissues of mice treated with cisplatin with prophylactic vitamin C supplementation (treatment mice) or phosphate-buffered saline (control mice) at 24 h after cisplatin treatment. Ascorbyl phosphate magnesium (APM), an oxidation-resistant vitamin C derivative, was found that led to global hypomethylation in the kidney tissue and regulated different functional genes in the promoter region and gene body region. Integrated evidence suggested that APM enhanced renal ion transport and metabolism, and reduced apoptosis and inflammation in the kidney tissues. Strikingly, Mapk15, Slc22a6, Cxcl5, and Cd44 were the potential targets of APM that conferred protection against cisplatin-induced AKI. Moreover, APM was found to be difficult to rescue cell proliferation and apoptosis caused by cisplatin in the Slc22a6 knockdown cell line. These results elucidate the mechanism by which vitamin C as an epigenetic regulator to protects against cisplatin-induced AKI and provides a new perspective and evidence support for controlling the disease process through regulating DNA methylation.

Applications and research progress of Traditional Chinese medicine delivered via nasal administration.

Nasal administration of Traditional Chinese medicine (TCM) has a long history of applications. With the gradual maturing of technology and pharmacological advances, nasal preparations of TCM have undergone significant changes. Nasal TCM formulations are used not only for treatment of pneumonia, asthma, sinusitis and allergic rhinitis but also Alzheimer's disease and Parkinson's disease, as antidepressants and antiepileptics, and in ischemia reperfusion. However, according to the analysis of nasal preparations of TCM currently on the market, most of them were compound preparations, which were used to treat allergic rhinitis (AR), common cold, headache and other local treatments, with a small range of diseases. At the same time, the dosage forms were mainly traditional dosage forms, aerosols and sprays, but there were no new dosage forms, which can not meet the clinical needs in terms of variety number, variety diversity and disease types. In this manuscript, we reviewed the development and applications of different nasal preparations of TCM from the aspects of nasal structure, origin, factors affecting absorption and common dosage forms, pharmacodynamics, targeting of nasal delivery and safety. In the near future, we expect that more nasal preparations of Chinese medicine with independent intellectual property rights will be marketed to meet the needs of clinical disease management.

Study and exploration of the pharmacokinetics of traditional Tibetan medicine Ruyi Zhenbao tablets after single and long-term administration.

Tibetan medicine is one of the oldest traditional medicine systems in the world. Taking the Ruyi Zhenbao tablet (RYZB) as an example, which is a widely used classic oral Tibetan medicine, this article discusses the pharmacokinetics of single administration and long-term treatment and analyzed its metabolic properties and tissue distribution in vivo. After single administration, blood samples were collected before administration and at different time points after administration in different groups of rats. In the study of long-term treatment effects, blood samples were collected from the animals in each group on days 1, 15, and 30 and on day 15 after withdrawal. The results showed that after a single administration, the dose change had no significant effect on the T1/2 and Tmax of agarotetrol, isoliquiritigenin, and piperine (p > 0.05). There was a certain correlation between the increase in AUC0-t and the Cmax of agarotetrol, isoliquiritigenin, piperine, and the increase in dosage, with a dose range of 0.225-0.900 g/kg. There were no significant differences in Cmax and AUC0-t of ferulic acid at different doses (p > 0.05). Meanwhile, there was no significant sex-based difference in the pharmacokinetic parameters of these four components in rats. After long-term administration, the distribution agarotetrol in various tissues of rats was kidney > liver > heart > brain; the tissue distribution in low- and medium-dose groups of isoliquiritigenin was liver > kidney > heart > brain, and in the high-dose group, kidney > liver > heart > brain. The tissue distribution of piperine in each dose group was liver > kidney > heart > brain, and that of ferulic acid in each dose group was kidney > liver > heart > brain. Through the establishment of the previously developed methodology, the pharmacokinetic properties of RYZB were analyzed after a single administration and long-term administration. Our findings confirmed this approach for the exploration and establishment of a pharmacokinetic evaluation of Tibetan medicine, to support its guiding role in clinical application, but also to accelerate research into Tibetan medicine theory and medicine and to provide a solid foundation for the translation of Tibetan medicine throughout the world.

Vitamin C Deficiency Causes Cell Type-Specific Epigenetic Reprogramming and Acute Tubular Necrosis in a Mouse Model.

BACKGROUND: Vitamin C deficiency is found in patients with variable kidney diseases. However, the role of vitamin C as an epigenetic regulator in renal homeostasis and pathogenesis remains largely unknown. METHODS: We showed that vitamin C deficiency leads to acute tubular necrosis (ATN) using a vitamin C-deficient mouse model (Gulo knock-out). DNA/RNA epigenetic modifications and injured S3 proximal tubule cells were identified in the vitamin C-deficient kidneys using whole-genome bisulfite sequencing, methylated RNA immunoprecipitation sequencing, and single-cell RNA sequencing. RESULTS: Integrated evidence suggested that epigenetic modifications affected the proximal tubule cells and fenestrated endothelial cells, leading to tubule injury and hypoxia through transcriptional regulation. Strikingly, loss of DNA hydroxymethylation and DNA hypermethylation in vitamin C-deficient kidneys preceded the histologic sign of tubule necrosis, indicating the causality of vitamin C-induced epigenetic modification in ATN. Consistently, prophylactic supplementation of an oxidation-resistant vitamin C derivative, ascorbyl phosphate magnesium, promoted DNA demethylation and prevented the progression of cisplatin-induced ATN. CONCLUSIONS: Vitamin C played a critical role in renal homeostasis and pathogenesis in a mouse model, suggesting vitamin supplementation may be an approach to lower the risk of kidney injury.

Multi-Omics Integration to Reveal the Mechanism of Hepatotoxicity Induced by Dictamnine.

Herb-induced liver injury (HILI) has become a great concern worldwide due to the widespread usage of herbal products. Among these products is Dictamni Cortex (DC), a well-known Traditional Chinese Medicine (TCM), widely used to treat chronic dermatosis. Dictamni Cortex has drawn increasing attention because of its hepatotoxicity caused by the hepatotoxic component, dictamnine. However, the potential hepatotoxicity mechanism of dictamnine remains unclear. Therefore, this study aimed to use the multi-omics approach (transcriptomic, metabolomic, and proteomic analyses) to identify genes, metabolites, and proteins expressions associated with dictamnine-induced hepatotoxicity. A study on mice revealed that a high dose of dictamnine significantly increases serum aspartate aminotransferase (AST) activity, total bilirubin (TBIL), and direct bilirubin (DBIL) levels, the relative liver weight and liver/brain weight ratio in female mice (P < 0.05 and P < 0.01), compared to the normal control group. Liver histologic analysis further revealed a high dose of dictamnine on female mice caused hepatocyte vesicular steatosis characterized by hepatocyte microvesicles around the liver lobules. The expressed genes, proteins, and metabolites exhibited strong associations with lipid metabolism disorder and oxidative stress. Dictamnine caused increased oxidative stress and early hepatic apoptosis via up-regulation of glutathione S transferase a1 (GSTA1) and Bax/Bcl-2 ratio and down-regulation of the antioxidative enzymes superoxide dismutase (SOD), catalase, and glutathione peroxidase 1 (GPx-1). Besides, the up-regulation of Acyl-CoA synthetase long-chain family member 4 (ACSL4) and down-regulation of acetyl-coa acetyltransferase 1 (ACAT1) and fatty acid binding protein 1 (FABP-1) proteins were linked to lipid metabolism disorder. In summary, dictamnine induces dose-dependent hepatotoxicity in mice, which impairs lipid metabolism and aggravates oxidative stress.

Research on the Species Difference of the Hepatotoxicity of Medicine Based on Transcriptome.

In recent years, several drugs have been withdrawn from use by regulatory bodies owing to hepatotoxicity; therefore, studies on drug-induced liver injury (DILI) are being actively pursued. Most studies evaluating DILI use rats or mice as animal models to determine drug toxicity; however, the toxicity of a drug can vary between rats or mice. These inconsistencies in in vivo studies among different animal models affect the extrapolation of experimental results to humans. Thus, it is particularly important to choose the most suitable animal model to determine drug hepatotoxicity owing to the genomic differences between rats and mice resulting from evolution. In this study, genome-wide transcriptome analysis was used to explore hepatotoxicity caused by differences in species. Our findings provide the preclinical basis to further study the mechanisms of drug hepatotoxicity and aid in the selection of animal models to determine drug safety. We used murine models (Sprague-Dawley and Wistar rats, ICR and Kunming mice) in this study and by using transcriptome sequencing with the differentially expressed genes in rat and mouse livers as the entry point, we explored the mechanism of oxidative stress and the difference in gene expression in the lipid-metabolism pathway between rats and mice. The clinically established hepatotoxic drugs, fructus psoraleae and acetaminophen were used to validate our study. Using pathological studies, we confirmed that oxidative stress in mice was more serious than that in rats, and that Kunming mice were more suited for the study of oxidative stress-related DILI. The validity of our findings was further verified based on gene expression. Thus, our study could serve as a valuable reference for the evaluation of potential preclinical hepatotoxicity. Moreover, it could be used in the prediction and early diagnosis of drug-induced liver injury caused by traditional Chinese medicine or synthetic drugs, thereby providing a new avenue for drug-toxicity studies.

[Potential hepatotoxic compounds and mechanisms of Epimedii Folium based on network toxicology and cell experimental validation].

To probe the potential hepatotoxic components of Epimedii Folium and investigate its mechanism based on network toxicology and cell experimental validation. According to the previous results of component measurement and cytotoxicity evaluation, 11 active compounds related to hepatotoxicity in Epimedii Folium were chosen as research object in this study. Through SwissTargetPrediction database and GeneCards database, the potentially hepatotoxic targets of Epimedii Folium were obtained. Subsequently, the protein-target interaction network and active compounds-hepatotoxic targets network were established to analyze the core targets and screen the key hepatotoxic compounds in Epimedii Folium. Meanwhile, the signaling pathways and molecular mechanisms were inferred with GO functional enrichment analysis and KEGG pathway enrichment analysis on the core targets. At last, the effect of icaritin as the chief hepatotoxic compound on the indexes related to hepatotoxicity in HL-7702 cells and HepG2 cells was investigated to validate the hepatotoxicity mechanism of Epimedii Folium. Through the network toxicology analysis, 190 action targets and 991 hepatotoxic targets were collected, then 64 potentially hepatotoxic targets of Epimedii Folium including AKT1, EGFR, MAPK3, TNF and so on were obtained, and icaritin was screened as the key hepatotoxic compound. GO functional enrichment analysis indicated 160 biological process terms such as protein phosphorylation and negative regulation of apoptotic process, 41 molecular function terms such as protein binding and ATP binding, and 32 cellular component terms such as cytosol and cell surface. KEGG pathway enrichment analysis inferred 75 signaling pathways involving PI3 K-Akt and HIF-1. After comprehensive analysis, it was inferred that the hepatotoxicity mechanism of Epimedii Folium was related with regulating oxidative stress and apoptosis. The results of cell biology experiments showed that icaritin could significantly increase the level of aspartate aminotransferase and lactate dehydrogenase, reduce the level of glutathione, improve the quality of reactive oxygen species and reduce mitochondrial membrane potential, indicating that it could cause hepatotoxicity by destroying cell membrane structure, inhibiting antioxidant enzyme activity, activating oxidative stress and inducing apoptosis. These results proved the reliability of results of network pharmacology. This study preliminarily clarified the material base and the mechanism of potential hepatotoxicity of Epimedii Folium, which provided important information for further research and safe application.