The effects of rhein on D-GalN/LPS-induced acute liver injury in mice: Results from gut microbiome-metabolomics and host transcriptome analysis

Gut microbiota causally affects drug-induced liver injury via plasma metabolites: a Mendelian randomization study

Background

The gut microbiota and plasma metabolites play important roles in the progression of drug-induced liver injury (DILI). We investigated the causal associations between the gut microbiota, plasma metabolome, and DILI.

Methods

The summary data for gut microbiota (n = 18,340), plasma metabolome (n = 8,299), and DILI (n = 366,838) were obtained from the large genome-wide association studies. A two-sample Mendelian randomization was performed to explore the associations between the gut microbiota, plasma metabolome, and DILI. Additionally, a two-step Mendelian randomization was performed to explore the potential metabolites.

Results

Five taxa were causally associated with DILI, including Oscillospira [odds ratio (OR) = 2.257, 95% confidence interval (CI) = 1.110-4.590], Blautia (OR = 2.311, 95% CI = 1.010-5.288), Roseburia (OR = 2.869, 95% CI = 1.429-5.761), Fusicatenibacter (OR = 1.995, 95% CI = 1.024-3.890), and Prevotella 7 (OR = 1.549, 95% CI = 1.065-2.253). Moreover, 53 metabolites were causally associated with DILI. After mediation analysis, four taxa were found to affect DILI through five mediation metabolites. N6-carbamoylthreonyladenosine mediated the effect of Blautia on DILI. Acetylcarnitine mediated the effect of Fusicatenibacter on DILI. In addition, 4-cholesten-3-one mediated the effect of Prevotella 7 on DILI. Furthermore, 5,6-dihydrothymine levels and the salicylate-to-citrate ratio mediated the effect of Oscillospira on DILI.

Conclusion

We found that the gut microbiota could affect DILI through plasma metabolites, which could serve as potential biomarkers for risk stratification and elucidate underlying mechanisms for further investigation of DILI.

Progress of mitochondrial and endoplasmic reticulum-associated signaling and its regulation of chronic liver disease by Chinese medicine

The endoplasmic reticulum (ER) is connected to mitochondria through mitochondria-associated ER membranes (MAMs). MAMs provide a framework for crosstalk between the ER and mitochondria, playing a crucial role in regulating cellular calcium balance, lipid metabolism, and cell death. Dysregulation of MAMs is involved in the development of chronic liver disease (CLD). In CLD, changes in MAMs structure and function occur due to factors such as cellular stress, inflammation, and oxidative stress, leading to abnormal interactions between mitochondria and the ER, resulting in liver cell injury, fibrosis, and impaired liver function. Traditional Chinese medicine has shown some research progress in regulating MAMs signaling and treating CLD. This paper reviews the literature on the association between mitochondria and the ER, as well as the intervention of traditional Chinese medicine in regulating CLD.

Anti-Inflammatory Effects of a Novel Nuclear Factor-κB Inhibitory Derivative Derived from Pyrazolo[3,4-d]Pyrimidine in Three Inflammation Models

Nuclear factor-κB (NF-κB) plays a central role in inflammatory responses, and its physiologic functions are essential for cell survival and proliferation. Currently, drugs targeting NF-κB inhibition have not yet been applied in clinical practice. We investigated the physiologic effect of a novel NF-κB inhibitory compound, 1H-pyrazolo[3,4-d]pyrimidin-4-amine derivative (INH #1), on three inflammatory animal models. The pharmacokinetics were measured by liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis. Acute hepatitis was induced by administrating lipopolysaccharide (LPS) and D-(+)-galactosamine hydrochloride followed by the analysis of survival time and inflammatory mediators. Collagen-induced arthritis (CIA) was induced by immunization with type II collagen (CII), and serum-transfer arthritis (STA) was caused by injecting K/BxN mice serum. Clinical and histologic scores were evaluated in both arthritis models. Immune cell subset analysis, CII-induced interferon-gamma (IFN-γ) production and proliferation, and measurement of anti-CII IgG antibodies were performed in the CIA model. In the acute hepatitis model, INH #1 suppressed tumor necrosis factor-α (TNF-α) production and prevented early death in a dose-dependent manner. INH #1 significantly attenuated arthritis scores and joint inflammation in both arthritis models. Additionally, in the CIA model, dendritic cells (DCs) in the regional lymph nodes were decreased in the treated mice and antigen-induced IFN-γ production and cell proliferation in splenocytes were inhibited, whereas the titers of anti-CII IgG antibodies were comparable regardless of the treatment. Here we revealed that INH #1 exerted anti-inflammatory effects in vivo via inhibition of inflammatory mediators and suppression of cellular immune responses. This compound could be a novel candidate for inhibition of NF-κB in certain inflammatory diseases. SIGNIFICANCE STATEMENT: A novel nuclear factor-κB (NF-κB) inhibitory compound, 1H-pyrazolo[3,4-d]pyrimidin-4-amine derivative (INH #1), which retains physiologically essential NF-κB bioactivity, suppressed inflammation in three different mouse models: the acute hepatitis model, the collagen-induced arthritis model, and the K/BxN serum-transfer arthritis model. These results suggest that this compound could be a novel and potent anti-inflammatory agent.

An UHPLC-QTOF-MS-based strategy for systematic profiling of chemical constituents and associated in vivo metabolites of a famous traditional Chinese medicine formula, Yinchenhao decoction

Yinchenhao decoction (YCHD), a famous traditional Chinese medicine formula, has been applied for relieving jaundice in China for more than 1800 years. However, the material basis for YCHD is still unclear, and the chemical composition and metabolism characteristic in vivo are undefined, making the potential effective constituents and mechanism of action unclear. Herein, an ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS)-based strategy was applied for the chemical profiling of YCHD, as well as their in vivo prototypes and global metabolites that defined the metabolome. Our results showed that a total of 139 chemicals were identified in YCHD, including 28 organic acids, 12 monoterpenoids, five diterpenes, three triterpenoids, 17 iridoids, 23 anthraquinones, 26 flavonoids, four coumarins and 21 other types. Moreover, 58 prototypes and 175 metabolites were found in rat biological samples after oral administration of YCHD; those distributed in plasma, liver, intestine and feces were suggested to be potentially effective substances. Oxidation, hydrogenation, decarboxylation and conjugations with methyl, sulfate and glucuronate were considered as the predominant metabolic pathways in vivo. In conclusion, this is a systemic study of chemical constituents and in vivo metabolome profiles of YCHD, contributing to the material basis understanding and further mechanism research.

A Biomimetic Multifunctional Nanoframework for Symptom Relief and Restorative Treatment of Acute Liver Failure

Acute liver failure (ALF) is a rare and serious condition characterized by major hepatocyte death and liver dysfunction. Owing to the limited therapeutic options, this disease generally has a poor prognosis and a high mortality rate. When ALF cannot be reversed by medications, liver transplantation is often needed. However, transplant rejection and the shortage of donor organs still remain major challenges. Most recently, stem cell therapy has emerged as a promising alternative for the treatment of liver diseases. However, the limited cell delivery routes and poor stability of live cell products have greatly hindered the feasibility and therapeutic efficacy of stem cell therapy. Inspired by the functions of mesenchymal stem cells (MSCs) primarily through the secretion of several factors, we developed an MSC-inspired biomimetic multifunctional nanoframework (MBN) that encapsulates the growth-promoting factors secreted by MSCs via combination with hydrophilic or hydrophobic drugs. The red blood cell (RBC) membrane was coated with the MBN to enhance its immunological tolerance and prolong its circulation time in blood. Importantly, the MBN can respond to the oxidative microenvironment, where it accumulates and degrades to release the payload. In this work, two biomimetic nanoparticles, namely, rhein-encapsulated MBN (RMBN) and N-acetylcysteine (NAC)-encapsulated MBN (NMBN), were designed and synthesized. In lipopolysaccharide (LPS)/d-galactosamine (D-GalN)-induced and acetaminophen (APAP)-induced ALF mouse models, RMBN and NMBN could effectively target liver lesions, relieve the acute symptoms of ALF, and promote liver cell regeneration by virtue of their strong antioxidative, anti-inflammatory, and regenerative activities. This study demonstrated the feasibility of the use of an MSC-inspired biomimetic nanoframework for treating ALF.

Hericium erinaceus Extract Exerts Beneficial Effects on Gut-Neuroinflammaging-Cognitive Axis in Elderly Mice

Ageing is a biological phenomenon that determines the impairment of cognitive performances, in particular, affecting memory. Inflammation and cellular senescence are known to be involved in the pathogenesis of cognitive decline. The gut microbiota-brain axis could exert a critical role in influencing brain homeostasis during ageing, modulating neuroinflammation, and possibly leading to inflammaging. Due to their anti-ageing properties, medicinal mushrooms can be utilised as a resource for developing pharmaceuticals and functional foods. Specifically, Hericium erinaceus (He), thanks to its bioactive metabolites, exerts numerous healthy beneficial effects, such as reinforcing the immune system, counteracting ageing, and improving cognitive performance. Our previous works demonstrated the capabilities of two months of He1 standardised extract oral supplementation in preventing cognitive decline in elderly frail mice. Herein, we showed that this treatment did not change the overall gut microbiome composition but significantly modified the relative abundance of genera specifically involved in cognition and inflammation. Parallelly, a significant decrease in crucial markers of inflammation and cellular senescence, i.e., CD45, GFAP, IL6, p62, and γH2AX, was demonstrated in the dentate gyrus and Cornus Ammonis hippocampal areas through immunohistochemical experiments. In summary, we suggested beneficial and anti-inflammatory properties of He1 in mouse hippocampus through the gut microbiome-brain axis modulation.