Liver-targeted delivery of asiatic acid nanostructured lipid carrier for the treatment of liver fibrosis

Integrated transcriptomics and metabolomics unravel the key metabolic pathways involved in the therapeutic mechanism of Salvianic acid A against hepatic fibrosis

Effective drugs for the clinical treatment of hepatic fibrosis have not yet been identified. Salvianic acid A (SAA) protective mechanisms primarily include anti-inflammation, anti-oxidative stress, and modulation of immune system function. Metabolic dysfunction is well recognized as the driver for hepatic fibrosis. However, the precise action mode and underlying mechanism of SAA in modulating hepatic metabolism to combat hepatic fibrosis remain incompletely understood. This study aimed to investigate the metabolic mechanism by which SAA improves hepatic fibrosis based on metabolomics and transcriptomics profiling. A mouse model of carbon tetrachloride (CCl4)-induced hepatic fibrosis mouse model was established, and protective effects of SAA were evaluated through pathological characteristics. Integrated metabolomics and transcriptomics analysis revealed three key altered metabolic pathways: bile secretion, carbohydrate digestion and absorption, and regulation of lipolysis in adipocytes. SAA modulated the bile secretion pathway, dependent on reducing water channel protein Aqp1, cholesterol synthesis enzyme Hmgcr and Na+/K+-ATPase enzyme Atp1a3, accompanied by up-regulating metabolites glutathione and glucose levels. SAA also regulated carbohydrate digestion and absorption by decreasing the glucose homeostasis-related Akt3, essential enzyme G6pc for gluconeogenesis/glycogenolysis and glucose transporter Atp1a3 with a concomitant increase of metabolites D-galactose, maltose, and sucrose levels. Moreover, SAA improved lipolysis in adipocytes in liver fibrosis through inhibiting lipolysis related Prkg1, lipid transporter Fabp4, lipolysis-associated Akt3 and increasing lipolysis mediator Adrb3, along with upregulated levels of metabolites adenosine monophosphate and norepinephrine. In conclusion, SAA alleviates hepatic fibrosis through modulating metabolic disorders, mainly relying on the metabolic improvements of bile secretion, carbohydrate digestion and absorption and adipocyte lipolysis.

Lipid nanosystems for fatty liver therapy and targeted medication delivery: a comprehensive review

Fatty liver is considered to be the most common chronic liver disease with a high global incidence, which can lead to cirrhosis and liver cancer in severe cases, and there is no specific drug for the treatment of fatty liver in the clinic. The use of lipid nanosystems has the potential to be an effective means of fatty liver treatment. The pathogenesis and intervening factors associated with the development of fatty liver are reviewed, and the advantages and the disadvantages of different lipid nanosystems for the treatment of fatty liver are comprehensively discussed, including liposomes, solid lipid nanoparticles, nanostructured lipid carriers, nanoemulsions, microemulsions, and phospholipid complexes. The composition and characterisation of these lipid nanosystems are highlighted and summarised with a view to improving the efficiency of lipid nanosystems for the treatment of fatty liver. In addition, active targeting and passive targeting strategies used for fatty liver therapy are discussed in detail.

Integrated oral microgel system ameliorates renal fibrosis by hitchhiking co-delivery and targeted gut flora modulation

BACKGROUND

Renal fibrosis is a progressive process associated with chronic kidney disease (CKD), contributing to impaired kidney function. Active constituents in traditional Chinese herbs, such as emodin (EMO) and asiatic acid (AA), exhibit potent anti-fibrotic properties. However, the oral administration of EMO and AA results in low bioavailability and limited kidney accumulation. Additionally, while oral probiotics have been accepted for CKD treatment through gut microbiota modulation, a significant challenge lies in ensuring their viability upon administration. Therefore, our study aims to address both renal fibrosis and gut microbiota imbalance through innovative co-delivery strategies.

RESULTS

In this study, we developed yeast cell wall particles (YCWPs) encapsulating EMO and AA self-assembled nanoparticles (NPYs) and embedded them, along with Lactobacillus casei Zhang, in chitosan/sodium alginate (CS/SA) microgels. The developed microgels showed significant controlled release properties for the loaded NPYs and prolonged the retention time of Lactobacillus casei Zhang (L. casei Zhang) in the intestine. Furthermore, in vivo biodistribution showed that the microgel-carried NPYs significantly accumulated in the obstructed kidneys of rats, thereby substantially increasing the accumulation of EMO and AA in the impaired kidneys. More importantly, through hitchhiking delivery based on yeast cell wall and positive modulation of gut microbiota, our microgels with this synergistic strategy of therapeutic and modulatory interactions could regulate the TGF-β/Smad signaling pathway and thus effectively ameliorate renal fibrosis in unilateral ureteral obstruction (UUO) rats.

CONCLUSION

In conclusion, our work provides a new strategy for the treatment of renal fibrosis based on hitchhiking co-delivery of nanodrugs and probiotics to achieve synergistic effects of disease treatment and targeted gut flora modulation.

Asiatic acid cyclodextrin inclusion micro-cocrystal for insoluble drug delivery and acute lung injury therapy enhancement

BACKGROUND

Acute lung injury (ALI) is a fatal respiratory disease caused by overreactive immune reactions (e.g., SARS-CoV-2 infection), with a high mortality rate. Its treatment is often compromised by inefficient drug delivery barriers and insufficient potency of the currently used drugs. Therefore, developing a highly effective lung-targeted drug delivery strategy is a pressing clinical need.

RESULTS

In this study, the micro-sized inclusion cocrystal of asiatic acid/γ-cyclodextrin (AA/γCD, with a stoichiometry molar ratio of 2:3 and a mean size of 1.8 μm) was prepared for ALI treatment. The dissolution behavior of the AA/γCD inclusion cocrystals followed a "spring-and-hover" model, which meaned that AA/γCD could dissolve from the cocrystal in an inclusion complex form, thereby promoting a significantly improved water solubility (nine times higher than free AA). This made the cyclodextrin-based inclusion cocrystals an effective solid form for enhanced drug absorption and delivery efficiency. The biodistribution experiments demonstrated AA/γCD accumulated predominantly in the lung (Cmax = 50 µg/g) after systemic administration due to the micron size-mediated passive targeting effect. The AA/γCD group showed an enhanced anti-inflammatory therapeutic effect, as evidenced by reduced levels of pro-inflammatory cytokines in the lung and bronchoalveolar lavage fluids (BALF). Histological examination confirmed that AA/γCD effectively inhibited inflammation reactions.

CONCLUSION

The micro-sized inclusion cocrystals AA/γCD were successfully delivered into the lungs by pulmonary administration and had a significant therapeutic effect on ALI.

Dual-Targeted Nanoparticle-in-Microparticle System for Ulcerative Colitis Therapy

Conventional oral therapy for ulcerative colitis (UC) is associated with premature release or degradation of drugs in the harsh gastrointestinal environment, resulting in reduced therapeutic effectiveness. Consequently, the present study aims to develop a dual-targeted delivery system with a nanoparticle-in-microparticle (nano-in-micro) structure. The prepared Asiatic Acid-loaded delivery system (AA/CDM-BT-ALG) has pH-sensitive properties. Cellular uptake evaluation confirms that nanoparticles exhibit targeted absorption by macrophages and Caco-2 cells through mannose (Man) receptor and biotin-mediated endocytosis, respectively. Therefore, this mechanism effectively enhances intracellular drug concentration. Additionally, the biodistribution study conducted on the gastrointestinal tract of mice indicates that the colon of the microspheres group shows higher fluorescence intensity with longer duration than the other groups. This finding indicates that the microspheres exhibit selective accumulation in areas of colon inflammation. In vivo experiments in colitis mice showed that AA/CDM-BT-ALG significantly alleviates the histopathological characteristics of the colon, reduced neutrophil, and macrophage infiltration, and decreases pro-inflammatory cytokine expression. Furthermore, the effect of AA/CDM-BT-ALG on colitis is validated to be closely related to the TLR4/MyD88/NF-κB signaling pathway. The present findings suggest that the development of a dual-targeted delivery system is accomplished effectively, with the potential to serve as a drug-controlled release system for treating UC.

Isovitexin alleviates hepatic fibrosis by regulating miR-21-mediated PI3K/Akt signaling and glutathione metabolic pathway: based on transcriptomics and metabolomics

BACKGROUND

Effective drugs for the treatment of hepatic fibrosis have not yet been identified. Isovitexin (IVT) is a promising hepatoprotective agent owing to its efficacy against acute liver injury. However, the role of IVT in liver fibrosis has not been reported.

PURPOSE

To explore the effect of IVT on liver fibrosis both in vitro and in vivo.

STUDY DESIGN AND METHODS

A mouse model of liver fibrosis induced by carbon tetrachloride (CCl4) and two types of hepatic stellate cell models induced by platelet-derived growth factor-BB (PDGF-BB) were established to evaluate the effect of IVT on hepatic fibrosis. Transcriptomics and metabolomics were used to predict the underlying targets of IVT and were validated by a combination of in vitro and in vivo experiments. Exploration of miRNA and N6-methyladenosine (m6A) modifications was also carried out to detect the key upstream targets of the above targets.

RESULTS

IVT reduced collagen deposition and hepatic stellate cell activation to alleviate liver fibrosis. The transcriptomics and metabolomics analyses showed that phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling and the glutathione (GSH) metabolic pathway may be the main regulatory processes of IVT in hepatic fibrosis. Both the in vitro and in vivo experiments confirmed the inhibitory effect of IVT on the PTEN-PI3K-Akt-mTOR axis and activation of the GSH metabolic pathway. A miR-21 mimic inhibited the effects of IVT on these two pathways, suggesting that miR-21 is the hub for IVT regulation of PI3K-Akt signaling and the GSH metabolic pathway. IVT also increased pri-miR-21 level and reduced the m6A enrichment of pri-miR-21, demonstrating that IVT may regulate pri-miR-21 through m6A modification, thereby affecting the maturation of miR-21.

CONCLUSION

This study is the first to propose a protective effect of IVT against liver fibrosis. The mechanism of IVT against hepatic fibrosis is based on the regulation of miR-21, targeting PTEN-Akt signaling and the GSH metabolic pathway, which is also a novel discovery.

Anti-Liver Fibrosis Role of miRNA-96-5p via Targeting FN1 and Inhibiting ECM-Receptor Interaction Pathway

The aberrant expression of mRNAs participates in the pathogenesis of hepatic fibrosis. However, the precise mechanisms regulated by microRNAs (miRNAs) remain unclear. This study aims to investigate the functions about differentially expressed mRNAs (DEMs) in liver fibrosis and their regulatory mechanisms. The DEMs datasets about hepatic stellate cells (HSCs) obtained from hepatic fibrosis mice versus HSCs obtained from normal mice were downloaded from the GEO database (GSE120281). According to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of the GSE120281 datasets, ECM-receptor interaction was the most significant enrichment pathway that was correlated with hepatic fibrosis, and the fibronectin 1 (FN1) gene was upregulated most significantly in the signaling pathway. Downregulation of the expression of the FN1 gene by transfecting with FN1-siRNA alleviated the activity of HSCs. Four different bioinformatics web-based tools were used to predict that microRNA-96-5p (miR-96-5p) would directly target FN1, and a luciferase assay further confirmed this. Moreover, miR-96-5p was declined in activated HSCs and FN1, whereas laminin γ1 (LAMC1), collagen 1α1 (COL1A1) in the ECM-receptor interaction pathway, and the fibrosis marker α-smooth muscle actin (α-SMA) could be reduced by upregulation of the miRNA. Additionally, miR-96-5p expression was low in CCl4-induced liver fibrosis mice. Increased miR-96-5p expression alleviated liver fibrosis, improved liver function, and inhibited the expression of α-SMA, FN1, COL1A1, and LAMC1. In conclusion, this study indicated that upregulation of miR-96-5p could reduce HSC activation and relieve hepatic fibrosis by restraining the FN1/ECM-receptor interaction pathway.

Pharmacokinetics and tumor delivery of nanoparticles

Nanoparticles (NPs) have been widely used in different areas, including consumer products and medicine. In terms of biomedical applications, NPs or NP-based drug formulations have been extensively investigated for cancer diagnostics and therapy in preclinical studies, but the clinical translation rate is low. Therefore, a thorough and comprehensive understanding of the pharmacokinetics of NPs, especially in drug delivery efficiency to the target therapeutic tissue tumor, is important to design more effective nanomedicines and for proper assessment of the safety and risk of NPs. This review article focuses on the pharmacokinetics of both organic and inorganic NPs and their tumor delivery efficiencies, as well as the associated mechanisms involved. We discuss the absorption, distribution, metabolism, and excretion (ADME) processes following different routes of exposure and the mechanisms involved. Many physicochemical properties and experimental factors, including particle type, size, surface charge, zeta potential, surface coating, protein binding, dose, exposure route, species, cancer type, and tumor size can affect NP pharmacokinetics and tumor delivery efficiency. NPs can be absorbed with varying degrees following different exposure routes and mainly accumulate in liver and spleen, but also distribute to other tissues such as heart, lung, kidney and tumor tissues; and subsequently get metabolized and/or excreted mainly through hepatobiliary and renal elimination. Passive and active targeting strategies are the two major mechanisms of tumor delivery, while active targeting tends to have less toxicity and higher delivery efficiency through direct interaction between ligands and receptors. We also discuss challenges and perspectives remaining in the field of pharmacokinetics and tumor delivery efficiency of NPs.

Effect of modification of polystyrene nanoparticles with different bile acids on their oral transport

Bile acid-modified nanomedicine is a promising strategy to improve oral bioavailability. However, the efficiencies of different bile acids have not been clarified. To clarify this issue, deoxycholic acid (DCA) and cholic acid (CA) and glycocholic acid (GCA) were conjugated to carboxylated polystyrene nanoparticle (CPN). The endocytosis, intracellular and transcellular transport among the NPs were compared in Caco-2 cells, and their oral pharmacokinetics profiles were studied in C57BL/6 J mice. It was found that DCPN demonstrated higher uptake and transcytosis rate. With modification by different bile acids, the transport pathways of the NPs were altered. In mice, GCPN showed the highest absorption speed and oral bioavailability. It was found that the synergic effect of hydrophobicity and ASBT affinity might lead to the difference between in vitro and in vivo transport. This study will build a basis for the rational design of bile acid-modified nanomedicines.

The Chinese herb Styrax triggers pharmacokinetic herb-drug interactions via inhibiting intestinal CYP3A

Human cytochrome P450 3A4 (hCYP3A4) is a predominant enzyme to trigger clinically relevant drug/herb-drug interactions (DDIs or HDIs). Although a number of herbal medicines have been found with strong anti-hCYP3A4 effects in vitro, the in vivo modulatory effects of herbal medicines on hCYP3A4 and their potential risks to trigger HDIs are rarely investigated. Herein, we demonstrate a case study to efficiently find the herbal medicine(s) with potent hCYP3A4 inhibition in vitro and to accurately assess the potential HDIs risk in vivo. Following screening over 100 herbal medicines, the Chinese herb Styrax was found with the most potent hCYP3A4 inhibition in HLMs. In vitro assays demonstrated that Styrax could potently inhibit mammalian CYP3A in liver and intestinal microsomes from both humans and rats. In vivo pharmacokinetic assays showed that Styrax (i.g., 100 mg/kg) significantly elevated the plasma exposure of two CYP3A-substrate drugs (midazolam and felodipine) when midazolam or felodipine was administered orally. By contrast, the plasma exposure of either midazolam or felodipine was hardly affected by Styrax (i.g.) when the victim drug was administered intravenously. Further investigations demonstrated that seven pentacyclic triterpenoid acids (PTAs) in Styrax were key substances responsible for CYP3A inhibition, while these PTAs could be exposed to intestinal tract at relatively high exposure levels but their exposure levels in rat plasma and liver were extremely low. These findings well explained why Styrax (i.g.) could elevate the plasma exposure of victim drugs only when these agents were orally administrated. Collectively, our findings demonstrate that Styrax can modulate the pharmacokinetic behavior of CYP3A-substrate drugs via inhibiting intestinal CYP3A, which is very helpful for the clinical pharmacologists to better assess the HDIs triggered by Styrax or Styrax-related herbal products.

Recent Advances Regarding the Molecular Mechanisms of Triterpenic Acids: A Review (Part I)

Triterpenic acids are phytocompounds with a widespread range of biological activities that have been the subject of numerous in vitro and in vivo studies. However, their underlying mechanisms of action in various pathologies are not completely elucidated. The current review aims to summarize the most recent literature, published in the last five years, regarding the mechanism of action of three triterpenic acids (asiatic acid, oleanolic acid, and ursolic acid), corelated with different biological activities such as anticancer, anti-inflammatory, antidiabetic, cardioprotective, neuroprotective, hepatoprotective, and antimicrobial. All three discussed compounds share several mechanisms of action, such as the targeted modulation of the PI3K/AKT, Nrf2, NF-kB, EMT, and JAK/STAT3 signaling pathways, while other mechanisms that proved to only be specific for a part of the triterpenic acids discussed, such as the modulation of Notch, Hippo, and MALAT1/miR-206/PTGS1 signaling pathway, were highlighted as well. This paper stands as the first part in our literature study on the topic, which will be followed by a second part focusing on other triterpenic acids of therapeutic value.