Augmenter of liver regeneration: Mitochondrial function and steatohepatitis

Nanoparticle-mediated sodium butyrate delivery for repairing hypoxic-ischemic brain injury in premature infants

Hypoxic-ischemic encephalopathy of prematurity (HIEP) is a leading cause of acute mortality and chronic neurological injury in premature infants. This study investigates the molecular mechanisms by which magnetic fluorescent nanoparticles loaded with sodium butyrate (MNs@SB) repair HIEP by modulating the Sp1 and TGF-β1 signaling pathways. Untargeted metabolomics analysis revealed significant suppression of the butyrate metabolism pathway in the intestinal tissues of HIEP mice. We synthesized and characterized MNs@SB nanoparticles, with zeta potential and DLS results indicating an average nanoparticle size of approximately 79.89 nm and a zeta potential of -36.87 mV. TEM images confirmed that the nanoparticles formed polymer-coated clusters. MNs@SB demonstrated excellent biocompatibility and stable magnetic targeting behavior. The nanoparticles were delivered to the brain via tail vein injection and magnetic targeting, with focused ultrasound facilitating their diffusion. The results showed that HIEP mice exhibited a significant increase in infarct size and extensive tissue loss, whereas MNs@SB treatment effectively reversed HIEP-induced brain damage, improving both short-term and long-term neurological deficits. Single-cell RNA sequencing and high-throughput transcriptome analysis revealed that MNs@SB promoted brain repair by upregulating neuronal Sp1, activating the TGF-β1 signaling pathway, and inhibiting neuronal apoptosis. In vivo experiments further confirmed that MNs@SB treatment restored SP1 mRNA and protein expression in the brain. Additionally, MNs@SB treatment significantly restored TGF-β1, p-SMAD2, and p-SMAD3 protein expression, indicating activation of the TGF-β1/SMAD2/3 signaling pathway. This study presents a novel nanomedicine therapeutic strategy with potential clinical applications.

The role of ubiquitination and deubiquitination in the pathogenesis of non-alcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases and is closely associated with metabolic abnormalities. The causes of NAFLD are exceedingly complicated, and it is known that a variety of signaling pathways, endoplasmic reticulum stress, and mitochondrial dysfunction play a role in the pathogenesis of NAFLD. Recent studies have shown that ubiquitination and deubiquitination are involved in the regulation of the NAFLD pathophysiology. Protein ubiquitination is a dynamic and diverse post-translational alteration that affects various cellular biological processes. Numerous disorders, including NAFLD, exhibit imbalances in ubiquitination and deubiquitination. To highlight the significance of this post-translational modification in the pathogenesis of NAFLD and to aid in the development of new therapeutic approaches for the disease, we will discuss the role of enzymes involved in the processes of ubiquitination and deubiquitination, specifically E3 ubiquitin ligases and deubiquitinating enzymes that are important in the regulation of NAFLD.

Molecular mechanisms in liver repair and regeneration: from physiology to therapeutics

Liver repair and regeneration are crucial physiological responses to hepatic injury and are orchestrated through intricate cellular and molecular networks. This review systematically delineates advancements in the field, emphasizing the essential roles played by diverse liver cell types. Their coordinated actions, supported by complex crosstalk within the liver microenvironment, are pivotal to enhancing regenerative outcomes. Recent molecular investigations have elucidated key signaling pathways involved in liver injury and regeneration. Viewed through the lens of metabolic reprogramming, these pathways highlight how shifts in glucose, lipid, and amino acid metabolism support the cellular functions essential for liver repair and regeneration. An analysis of regenerative variability across pathological states reveals how disease conditions influence these dynamics, guiding the development of novel therapeutic strategies and advanced techniques to enhance liver repair and regeneration. Bridging laboratory findings with practical applications, recent clinical trials highlight the potential of optimizing liver regeneration strategies. These trials offer valuable insights into the effectiveness of novel therapies and underscore significant progress in translational research. In conclusion, this review intricately links molecular insights to therapeutic frontiers, systematically charting the trajectory from fundamental physiological mechanisms to innovative clinical applications in liver repair and regeneration.

Augmenter of liver regeneration inhibits renal fibrosis during acute kidney injury to chronic kidney disease transition by regulating autophagic flux

BACKGROUND

Augmenter of liver regeneration (ALR) is believed to protect against acute kidney injury (AKI). The objective of this study was to investigate the mechanisms of ALR in the transition from AKI to chronic kidney disease (CKD).

METHODS

ALR Conditional Knockout (CKO) mice were bilateral renal artery clamped to induce AKI and CKD. Serum creatinine, blood urea nitrogen, and uric acid were measured to reflect renal function. Renal histology was used to assess kidney damage. Transcriptome sequencing and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were used to identify differentially expressed genes (DEGs) and related pathways. TUNEL assay was conducted to assess apoptosis. Polymerase chain reaction and immunohistology were used to analyze autophagy-related factors and kidney fibrosis. AAV9-mRFP-GFP-LC3 was injected to observe autophagy flux.

RESULTS

In the murine models of AKI and CKD, loss of ALR led to markedly reduced renal function and renal tubular pathology injury. Multiple autophagy-related pathways were found to be enriched in up-regulated DEGs in transcriptome sequencing of ALR CKO and control groups with AKI. Renal fibrosis was evident in ALR CKO mice, with marked suppression of Beclin-1, a factor associated with the initiation phase of autophagy, and ATG5, an important factor in the extension phase of autophagosomes. The marked accumulation of LC3 and SQSTM1/P62, which is associated with the formation of autophagosomes, was also observed, suggesting an impairment of autophagic processes. Correspondingly, the AAV9-mRFP-GFP-LC3 results indicated that decreased ALR led to the accumulation of autophagosomes and impaired autophagic lysosome generation.

CONCLUSIONS

Collectively, these results suggested that ALR deficiency led to apoptosis and enhanced renal fibrosis by impairing autophagic flux, which in turn led to the transition of AKI to CKD.

Altered mitochondrial unfolded protein response and FGF21 secretion in MASLD progression and the effect of exercise intervention

A high-calorie diet and lack of exercise are the most important risk factors contributing to metabolic dysfunction-associated steatotic liver disease (MASLD) initiation and progression. The precise molecular mechanisms of mitochondrial function alteration during MASLD development remain to be fully elucidated. In this study, a total of 60 male C57BL/6J mice were maintained on a normal or amylin liver NASH (AMLN) diet for 6 or 10 weeks. Some of the mice were then subjected to voluntary wheel running, while the other mice were fed a normal or AMLN diet until 14 and 18 weeks. The results showed that hepatic lipid deposition and the PERK-eIF2α-ATF4 pathway were significantly increased with prolonged duration of AMLN diet. However, expression of mitochondrial unfolded protein response (UPRmt) genes and mitokine FGF21 secretion were significantly enhanced in the 14-week AMLN diet mice, but were markedly reduced with the excessive lipid deposition induced by longer AMLN diet. Additionally, the exercise intervention acts as a regulator to optimize UPRmt signal transduction and to enhance mitochondrial homeostasis by improving mitochondrial function, reversing the UPRmt activation pattern, and increasing FGF21 secretion, which plays a pivotal role in delaying the occurrence and development of MASLD.

Microbiome and metabolomics reveal the effect of gut microbiota on liver regeneration of fatty liver disease

BACKGROUND

Metabolic dysfunction-associated fatty liver disease (MAFLD) is associated with impaired regenerative capacity and poor postoperative prognosis following hepatectomy. Previous research has highlighted the importance of the gut-liver axis in the physiological and pathological processes of the liver. However, the contribution of gut bacteria to the regeneration of livers with MAFLD and its metabolic regulatory mechanisms remain elusive.

METHODS

Partial hepatectomy (PHx) was performed on C57Bl/6J mice fed with high-fat diet (HFD) for 12 weeks. Pathological examination, immunohistochemistry, and qRT-PCR analysis were performed to assess the severity of steatosis and proliferative potential. The gut microbiome was examined by 16S rRNA gene sequencing and shotgun metagenomics, whereas liver metabolomics was analysed via untargeted and targeted metabolomics using liquid chromatography-tandem mass spectrometry (LC-MS).

FINDINGS

HFD-induced hepatic steatosis in mice led to impaired liver regeneration following PHx. The gut microbiota and liver metabolites were altered along with the liver regeneration process. Longitudinal time-series analysis revealed dynamic alterations in these data, whereas correlation analysis screened out bacterial candidates that potentially influence liver regeneration in MAFLD by modulating metabolic pathways. Among these bacteria, the dominant bacterium Akkermansia was selected for subsequent investigation. MAFLD mice gavaged with Akkermansia muciniphila (A. muciniphila) exhibited reduced liver lipid accumulation and accelerated liver regeneration, possibly through the regulation of the tricarboxylic acid (TCA) cycle.

INTERPRETATION

These data demonstrated the interplay between the gut microbiome, liver metabolomics, and liver regeneration in mice with MAFLD. A. muciniphila has the potential to serve as a clinical intervention agent to accelerate postoperative recovery in MAFLD.

FUNDING

This work was supported by the Research Project of Jinan Microecological Biomedicine Shandong Laboratory [JNL-2022008B]; the Zhejiang Provincial Natural Science Foundation of China [LZ21H180001]; the Fundamental Research Funds for the Central Universities [No. 2022ZFJH003].

New therapeutic approaches for fibrosis: harnessing translational regulation

Idiopathic pulmonary fibrosis (IPF) is a progressive and debilitating lung disease characterized by excessive extracellular matrix deposition and tissue scarring. The median survival of patients with IPF is only 4.5 years following diagnosis, and effective treatment options are scarce. Recent studies found aberrant translation of specific mRNAs in various fibrosing diseases, highlighting the role of key translational regulators, including RNA binding proteins (RBPs), microRNAs, long noncoding RNAs, and transcript modifications. Notably, when inhibited, 10 profibrotic RBPs cause a significant attenuation of fibrosis, illuminating potential therapeutic targets. In this review, we describe translational regulation in fibrosis and highlight a model where a conserved evolutionary mechanism may explain this regulation.

Bibliometric analysis of autophagy in NAFLD from 2004 to 2023

BACKGROUND

Autophagy is a cellular process in which damaged organelles or unnecessary proteins are encapsulated into double-membrane structures and transported to lysosomes for degradation. Autophagy plays a crucial role in various liver diseases, including nonalcoholic fatty liver disease. This study aims to elucidate the role of autophagy in nonalcoholic fatty liver disease through bibliometric analysis.

METHODS

Literature was retrieved from Web of Science CoreCollection database, and the search time was from January 01, 2004 to December 31, 2023. Data retrieval was performed using the Bibliometrix package in R software. VOSviewer and CiteSpace were utilized to visualize the research hotspots and trends related to the effect of autophagy on nonalcoholic fatty liver disease.

RESULTS

A total of 966 papers were obtained, published in 343 journals from 1385 institutions across 57 countries. The journals with the most publications were the "International Journal of Molecular Sciences" and "Scientific Reports." China had the highest number of published papers. The most productive authors were Yen Paul M and Jung Tae Woo, while Singh R was the most frequently co-cited author. Emerging research hotspots were associated with keywords such as insulin resistance, ferroptosis, endoplasmic reticulum stress, and mitochondrial function.

CONCLUSION

Research on autophagy in nonalcoholic fatty liver disease is still in its early stages, with a growing body of literature. This study is the first to provide a comprehensive bibliometric analysis, synthesizing research trends and advancements. It identifies current development trends, global cooperation models, foundational knowledge, research hotspots, and emerging frontiers in the field.

Augmenter of Liver Regeneration Crotonylation Assists in Mitochondria-ER Contact to Alleviate Hepatic Steatosis

BACKGROUND & AIMS

Crotonylation (Kcr), a newly identified post-translation modification (PTM), has been confirmed to be involved in diverse biological processes and human diseases as well. Metabolic dysfunction-associated steatotic liver disease (MASLD) poses a serious threat to people's health. Augmenter of liver regeneration (ALR) is an important liver regulatory protein, and the insufficiency of ALR expression is reported to accelerate liver steatosis progression to liver fibrosis or even hepatic carcinoma (HCC). However, the connection between dysregulated ALR crotonylation and MASLD pathogenesis remains largely unknown.

METHODS

Steatotic liver samples from human and Western diet (WD)-fed mice were employed for detecting Kcr levels. Mitochondrial function and mitochondria-ER interaction (MAM) relevant to ALR-Kcr modification was evaluated for hepatocyte lipid metabolism both in in vivo and in vitro experiments.

RESULTS

Global protein crotonylation (Kcr) as well as ALR-Kcr was significantly decreased in liver samples of patients with MASLD and WD mice. Histone deacetylase1/2 (HDAC1/2) and lysine acetyltransferase 8 (KAT8) were identified responsible for regulation of ALR-Kcr, which takes place at lysine 78 (K78). The decrease of ALR crotonylation might be related to the imbalance between HDAC1/2 and KAT8 expression, inhibited its interaction with MFN2, expanding MAM distance and impairing mitochondrial lipid metabolism, and consequently deteriorating hepatic steatosis.

CONCLUSIONS

The insufficient ALR crotonylation might be a crucial mechanism contributing to the pathogenesis of MASLD. Keeping ALR crotonylation level would be beneficial for the prevention and treatment of MASLD.

Carbon monoxide-loaded red blood cells ameliorate metabolic dysfunction-associated steatohepatitis progression via enhancing AMP-activated protein kinase activity and inhibiting Kupffer cell activation

Metabolic dysfunction-associated steatohepatitis (MASH) is a progressive form of nonalcoholic fatty liver disease characterised by fat accumulation, inflammation, oxidative stress, fibrosis, and impaired liver regeneration. In this study, we found that heme oxygenase-1 (HO-1) is induced in both MASH patients and in a MASH mouse model. Further, hepatic carbon monoxide (CO) levels in MASH model mice were >2-fold higher than in healthy mice, suggesting that liver HO-1 is activated as MASH progresses. Based on these findings, we used CO-loaded red blood cells (CO-RBCs) as a CO donor in the liver, and evaluated their therapeutic effect in methionine-choline deficient diet (MCDD)-induced and high-fat-diet (HFD)-induced MASH model mice. Intravenously administered CO-RBCs effectively delivered CO to the MASH liver, where they prevented fat accumulation by promoting fatty acid oxidation via AMP-activated protein kinase (AMPK) activation and peroxisome proliferator-activated receptor induction. They also markedly suppressed Kupffer cell activation and their corresponding anti-inflammatory and antioxidative stress activities in MASH mice. CO-RBCs also helped to restore liver regeneration in mice with HFD-induced MASH by activating AMPK. We confirmed the underlying mechanisms by performing in vitro experiments in RAW264.7 cells and palmitate-stimulated HepG2 cells. Taken together, CO-RBCs show potential as a promising cellular treatment for MASH.

Salvianolic acid A attenuates non-alcoholic fatty liver disease by regulating the AMPK-IGFBP1 pathway

Non-alcoholic fatty liver disease (NAFLD) affects approximately a quarter of the population and, to date, there is no approved drug therapy for this condition. Individuals with type 2 diabetes mellitus (T2DM) are at a significantly elevated risk of developing NAFLD, underscoring the urgency of identifying effective NAFLD treatments for T2DM patients. Salvianolic acid A (SAA) is a naturally occurring phenolic acid that is an important component of the water-soluble constituents isolated from the roots of Salvia miltiorrhiza Bunge. SAA has been demonstrated to possess anti-inflammatory and antioxidant stress properties. Nevertheless, its potential in ameliorating diabetes-associated NAFLD has not yet been fully elucidated. In this study, diabetic ApoE-/- mice were employed to establish a NAFLD model via a Western diet. Following this, they were treated with different doses of SAA (10 mg/kg, 20 mg/kg) via gavage. The study demonstrated a marked improvement in liver injury, lipid accumulation, inflammation, and the pro-fibrotic phenotype after the administration of SAA. Additionally, RNA-seq analysis indicated that the primary pathway by which SAA alleviates diabetes-induced NAFLD involves the cascade pathways of lipid metabolism. Furthermore, SAA was found to be effective in the inhibition of lipid accumulation, mitochondrial dysfunction and ferroptosis. A functional enrichment analysis of RNA-seq data revealed that SAA treatment modulates the AMPK pathway and IGFBP-1. Further experimental results demonstrated that SAA is capable of inhibiting lipid accumulation through the activation of the AMPK pathway and IGFBP-1.

The role of mitochondrial genes in ischemia-reperfusion injury: A systematic review of experimental studies

Mitochondrial dysfunction contributes to pathological conditions like ischemia-reperfusion (IR) injury. To address the lack of effective therapeutic interventions for IR injury and potential knowledge gaps in the current literature, we systematically reviewed 3800 experimental studies across 5 databases and identified 20 mitochondrial genes impacting IR injury in various organs. Notably, CyPD, Nrf2, and GPX4 are well-studied genes consistently influencing IR injury outcomes. Emerging genes like ALDH2, BNIP3, and OPA1 are supported by human genetic evidence, thereby warranting further investigation. Findings of this review can inform future research directions and inspire therapeutic advancements.

Zinc ions regulate mitochondrial quality control in neurons under oxidative stress and reduce PANoptosis in spinal cord injury models via the Lgals3-Bax pathway

Spinal cord injury is a serious traumatic nervous system disorder characterized by extensive neuronal apoptosis. Oxidative stress, a key factor in neuronal apoptosis, leads to the accumulation of reactive oxygen species, making mitochondrial quality control within cells crucial. Previous studies have demonstrated zinc's anti-inflammatory and anti-apoptotic properties in protecting mitochondria during spinal cord injury treatment, yet the precise mechanisms remain elusive. Single-cell sequencing analysis has identified Lgals3 and Bax as core genes in apoptosis. This study aimed to investigate whether zinc ions protect intracellular mitochondria by inhibiting the apoptotic proteins Lgals3 and Bax. We elucidated zinc ions' key role in mitigating mitochondrial quality control dysfunction triggered by oxidative stress and confirmed this was achieved by targeting the Lgals3-Bax pathway. Zinc's inhibitory effect on this pathway not only preserved mitochondrial integrity but also significantly reduced PANoptosis after spinal cord injury. Under oxidative stress, zinc ion regulation of mitochondrial quality control reveals an organelle-targeted therapeutic strategy, offering a novel approach for more precise treatment of spinal cord injury.

Comparative Transcriptome Analysis Unveils Regulatory Factors Influencing Fatty Liver Development in Lion-Head Geese under High-Intake Feeding Compared to Normal Feeding

The lion-head goose is the only large goose species in China, and it is one of the largest goose species in the world. Lion-head geese have a strong tolerance for massive energy intake and show a priority of fat accumulation in liver tissue through special feeding. Therefore, the aim of this study was to investigate the impact of high feed intake compared to normal feeding conditions on the transcriptome changes associated with fatty liver development in lion-head geese. In this study, 20 healthy adult lion-head geese were randomly assigned to a control group (CONTROL, n = 10) and high-intake-fed group (CASE, n = 10). After 38 d of treatment, all geese were sacrificed, and liver samples were collected. Three geese were randomly selected from the CONTROL and CASE groups, respectively, to perform whole-transcriptome analysis to analyze the key regulatory genes. We identified 716 differentially expressed mRNAs, 145 differentially expressed circRNAs, and 39 differentially expressed lncRNAs, including upregulated and downregulated genes. GO enrichment analysis showed that these genes were significantly enriched in molecular function. The node degree analysis and centrality metrics of the mRNA-lncRNA-circRNA triple regulatory network indicate the presence of crucial functional nodes in the network. We identified differentially expressed genes, including HSPB9, Pgk1, Hsp70, ME2, malic enzyme, HSP90, FADS1, transferrin, FABP, PKM2, Serpin2, and PKS, and we additionally confirmed the accuracy of sequencing at the RNA level. In this study, we studied for the first time the important differential genes that regulate fatty liver in high-intake feeding of the lion-head goose. In summary, these differentially expressed genes may play important roles in fatty liver development in the lion-head goose, and the functions and mechanisms should be investigated in future studies.

Augmenter of liver regeneration knockout aggravates tubular ferroptosis and macrophage activation by regulating carnitine palmitoyltransferase-1A-induced lipid metabolism in diabetic nephropathy

AIM

Ferroptosis is a novel type of programmed cell death that performs a critical function in diabetic nephropathy (DN). Augmenter of liver regeneration (ALR) exists in the inner membrane of mitochondria, and inhibits inflammation, apoptosis, and oxidative stress in acute kidney injury; however, its role in DN remains unexplored. Here, we aimed to identify the role of ALR in ferroptosis induction and macrophage activation in DN.

METHODS

The expression of ALR was examined in DN patients, db/db DN mice, and HK-2 cells treated with high glucose (HG). The effects of ALR on ferroptosis and macrophage activation were investigated with ALR conditional knockout, lentivirus transfection, transmission electron microscopy, qRT-PCR and western blotting assay. Mass spectrometry and rescue experiments were conducted to determine the mechanism of ALR.

RESULTS

ALR expression was reduced in the kidney tissues of DN patients and mice, serum of DN patients, and HG-HK-2 cells. Moreover, the inhibition of ALR promoted ferroptosis, macrophage activation, and DN progression. Mechanistically, ALR can directly bind to carnitine palmitoyltransferase-1A (CPT1A), the key rate-limiting enzyme of fatty acid oxidation (FAO), and inhibit the expression of CPT1A to regulate lipid metabolism involving FAO and lipid droplet-mitochondrial coupling in DN.

CONCLUSION

Taken together, our findings revealed a crucial protective role of ALR in ferroptosis induction and macrophage activation in DN and identified it as an alternative diagnostic marker and therapeutic target for DN.

Revitalizing Ancient Mitochondria with Nano-Strategies: Mitochondria-Remedying Nanodrugs Concentrate on Disease Control

Mitochondria, widely known as the energy factories of eukaryotic cells, have a myriad of vital functions across diverse cellular processes. Dysfunctions within mitochondria serve as catalysts for various diseases, prompting widespread cellular demise. Mounting research on remedying damaged mitochondria indicates that mitochondria constitute a valuable target for therapeutic intervention against diseases. But the less clinical practice and lower recovery rate imply the limitation of traditional drugs, which need a further breakthrough. Nanotechnology has approached favorable regiospecific biodistribution and high efficacy by capitalizing on excellent nanomaterials and targeting drug delivery. Mitochondria-remedying nanodrugs have achieved ideal therapeutic effects. This review elucidates the significance of mitochondria in various cells and organs, while also compiling mortality data for related diseases. Correspondingly, nanodrug-mediate therapeutic strategies and applicable mitochondria-remedying nanodrugs in disease are detailed, with a full understanding of the roles of mitochondria dysfunction and the advantages of nanodrugs. In addition, the future challenges and directions are widely discussed. In conclusion, this review provides comprehensive insights into the design and development of mitochondria-remedying nanodrugs, aiming to help scientists who desire to extend their research fields and engage in this interdisciplinary subject.

Topical rhubarb charcoal-crosslinked chitosan/silk fibroin sponge scaffold for the repair of diabetic ulcers improves hepatic lipid deposition in db/db mice via the AMPK signalling pathway

BACKGROUND

Type 2 diabetes mellitus (T2DM) is closely linked to metabolic syndrome, characterised by insulin resistance, hyperglycaemia, abnormal lipid metabolism, and chronic inflammation. Diabetic ulcers (DUs) comprise consequential complications that arise as a result of T2DM. To investigate, db/db mice were used for the disease model. The findings demonstrated that a scaffold made from a combination of rhubarb charcoal-crosslinked chitosan and silk fibroin, designated as RCS/SF, was able to improve the healing process of diabetic wounds in db/db mice. However, previous studies have primarily concentrated on investigating the impacts of the RSC/SF scaffold on wound healing only, while its influence on the entire body has not been fully elucidated.

MATERIAL AND METHODS

The silk fibroin/chitosan sponge scaffold containing rhubarb charcoal was fabricated in the present study using a freeze-drying approach. Subsequently, an incision with a diameter of 8 mm was made on the dorsal skin of the mice, and the RCS/SF scaffold was applied directly to the wound for 14 days. Subsequently, the impact of RCS/SF scaffold therapy on hepatic lipid metabolism was assessed through analysis of serum and liver biochemistry, histopathology, quantitative real-time PCR (qRT-PCR), immunohistochemistry, and Western blotting.

RESULTS

The use of the RCS/SF scaffold led to an enhancement in the conditions associated with serum glucolipid metabolism in db/db mice. An assessment of hepatic histopathology further confirmed this enhancement. Additionally, the qRT-PCR analysis revealed that treatment with RCS/SF scaffold resulted in the downregulation of genes associated with fatty acid synthesis, fatty acid uptake, triglyceride (TG) synthesis, gluconeogenesis, and inflammatory factors. Moreover, the beneficial effect of the RCS/SF scaffold on oxidative stress was shown by assessing antioxidant enzymes and lipid peroxidation. Additionally, the network pharmacology analysis verified that the adenosine monophosphate-activated protein kinase (AMPK) signalling pathway had a vital function in mitigating non-alcoholic fatty liver disease (NAFLD) by utilizing R. officinale. The measurement of AMPK, sterol regulatory element binding protein 1 (SREBP1), fatty acid synthase (FASN), and acetyl CoA carboxylase (ACC) gene and protein expression provided support for this discovery. Furthermore, the molecular docking investigations revealed a robust affinity between the active components of rhubarb and the downstream targets of AMPK (SREBP1 and FASN).

CONCLUSION

By regulating the AMPK signalling pathway, the RCS/SF scaffold applied topically effectively mitigated hepatic lipid accumulation, decreased inflammation, and attenuated oxidative stress. The present study, therefore, emphasises the crucial role of the topical RCS/SF scaffold in regulating hepatic lipid metabolism, thereby confirming the concept of "external and internal reshaping".

Jianpi Shengqing Huazhuo Formula improves abnormal glucose and lipid metabolism in obesity by regulating mitochondrial biogenesis

ETHNOPHARMACOLOGICAL RELEVANCE

Jianpi Shengqing Huazhuo Formula (JSH) is a modified prescription based on traditional Chinese medicine theory and classic prescriptions (Buzhong Yiqi Decoction and Yuye Decoction). It has been found that JSH has a good effect on obese patients with early abnormal glucose and lipid metabolism. Therefore, this experiment was conducted to study its clinical efficacy and pharmacological effect.

AIM OF THE STUDY

To observe the clinical efficacy of JSH and explore the mechanism of the formula to improve glucose and lipid metabolism in obese rats.

MATERIALS AND METHODS

1.

CLINICAL OBSERVATION

10 overweight/obese patients with abnormal glucose and lipid metabolism were selected to observe the indicators of serum glucose, serum lipids and liver damage of the patients before and after treatment with JSH. 2. Animal experiments: Fifty Sprague-Dawley (SD) rats were randomly divided into control group, model group, Metformin group (120 mg/kg/day), JSH-L group (5 g/kg/day) and JSH-H group (20 g/kg/day), with 10 rats in each group. The obese SD rat model was produced by feeding 60% high-fat diet for 8 weeks, and the drug group was given prophylactic administration for 8 weeks. At the end of the experiment, body weight, abdominal fat, plasma glucose, plasma lipids, plasma alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were measured. The levels of interleukin-6 (IL-6), interleukin 1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α) in plasma were detected by Elisa, and the changes of malondialdehyde (MDA), glutathione (GSH) and catalase (CAT) in plasma and liver tissue were detected by kits. The pathological changes and lipid deposition in liver were observed by HE staining and oil red O staining, and the changes in the number of mitochondria in liver cells were observed by transmission electron microscopy. RT-qPCR and Western Blot (WB) were used to detect the mitochondrial regulation-related indicators PGC-1α, NRF1, TFAM, MFN2, DRP1 and apoptosis-related indicators Bcl-2, Bax, caspase 8 in liver tissue.

RESULTS

1.

CLINICAL OBSERVATION

After one month administration, the patient's body weight, BMI, 2 h oral glucose tolerance test (2hOGTT), glycated hemoglobin (HbA1c), triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) decreased significantly, and the indicators of liver damage AST and ALT also decreased significantly. 2. Animal experiments: JSH can significantly reduce body weight and abdominal fat area, improve glucose and lipid metabolism, and also reduce plasma IL-6, IL-1β and TNF-α content in obese rats, and improve oxidative stress; HE staining and oil red O staining also showed that JSH can alleviate liver damage and lipid deposition in the liver. Further observations of liver cell ultrastructure showed that JSH can ameliorate the reduction of liver mitochondria caused by a high-fat diet and promote the expression of indicators of mitochondrial biogenesis related to PGC-1α, NRF1, and TFAM. Moreover, JSH could promote the expression of MFN2 and DRP1, decrease Bcl-2 and increase Bax in the liver.

CONCLUSIONS

1.

CLINICAL OBSERVATION

JSH can reduce body weight, serum glucose, serum lipid, and liver injury in overweight/obese patients. 2. Animal experiments: JSH regulates PGC-1α/NRF1/TFAM signaling pathway promotes liver mitochondrial biogenesis, improves glucose and lipid metabolism in obese rats, and regulates mitochondrial dependent apoptosis indicators Bcl-2/Bax to reduce liver injury.

Calenduloside E ameliorates non-alcoholic fatty liver disease via modulating a pyroptosis-dependent pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Non-alcoholic fatty liver disease (NAFLD) is a prevalent chronic liver condition that can have multiple underlying causes. There are no satisfactory chemical or biological drugs for the treatment of NAFLD. Longyasongmu, the bark and root of Aralia elata (Miq.) Seem, is used extensively in traditional Chinese medicine (TCM) and has been used in treating diverse liver diseases including NAFLD. Based on Aralia elata (Miq.) Seem as the main ingredient, Longya Gantai Capsules have been approved for use in China for the treatment of acute hepatitis and chronic hepatitis. Calenduloside E (CE), a natural pentacyclic triterpenoid saponin, is a significant component of saponin isolated from the bark and root of Aralia elata (Miq.) Seem. However, the role and mechanism of anti-NAFLD effects of CE is still unclear.

AIM OF THE STUDY

The objective of this study was to examine the potential mechanisms underlying the protective effect of CE on NAFLD.

MATERIALS AND METHODS

In this study, an NAFLD model was established by Western diet in apoE-/- mice, followed by treatment with various doses of CE (5 mg/kg, 10 mg/kg). The anti-NAFLD effect of CE was assessed by the liver injury, lipid accumulation, inflammation, and pro-fibrotic phenotype. The mechanism of CE in ameliorating NAFLD was studied through transcriptome sequencing (RNA-seq). In vitro, the mouse hepatocytes (AML-12) were stimulated in lipid mixtures with CE and performed the exploration and validation of the relevant pathways using Western blot, immunofluorescence, etc. RESULTS: The findings revealed a significant improvement in liver injury, lipid accumulation, inflammation, and pro-fibrotic phenotype upon CE administration. Furthermore, RNAseq analysis indicated that the primary pathway through which CE alleviates NAFLD involves pyroptosis-related inflammatory cascade pathways. Furthermore, it was observed that CE effectively suppressed inflammasome-mediated pyroptosis both in vivo and in vitro. Remarkably, the functional enrichment analysis of RNA-seq data revealed that the PI3K-Akt signaling pathway is the primarily Signaling transduction pathway modulated by CE treatment. Subsequent experimental outcomes provided further validation of CE's ability to hinder inflammasome-mediated pyroptosis through the inhibition of PI3K/AKT/NF-κB signaling pathway.

CONCLUSIONS

These findings present a novel pharmacological role of CE in exerting anti-NAFLD effects by inhibiting pyroptosis signaling pathways.

Subcellular distribution of prohibitin 1 in rat liver during liver regeneration and its cellular implication

BACKGROUND

The function of prohibitin 1 (Phb1) during liver regeneration (LR) remains relatively unexplored. Our previous research identified downregulation of Phb1 in rat liver mitochondria 24 h after 70% partial hepatectomy (PHx), as determined by subcellular proteomic analysis.

AIM

To investigate the potential role of Phb1 during LR.

METHODS

We examined changes in Phb1 mRNA and protein levels, subcellular distribution, and abundance in rat liver during LR following 70% PHx. We also evaluated mitochondrial changes and apoptosis using electron microscopy and flow cytometry. RNA-interference-mediated knockdown of Phb1 (PHBi) was performed in BRL-3A cells.

RESULTS

Compared with sham-operation control groups, Phb1 mRNA and protein levels in 70% PHx test groups were downregulated at 24 h, then upregulated at 72 and 168 h. Phb1 was mainly located in mitochondria, showed a reduced abundance at 24 h, significantly increased at 72 h, and almost recovered to normal at 168 h. Phb1 was also present in nuclei, with continuous increase in abundance observed 72 and 168 h after 70% PHx. The altered ultrastructure and reduced mass of mitochondria during LR had almost completely recovered to normal at 168 h. PHBi in BRL-3A cells resulted in increased S-phase entry, a higher number of apoptotic cells, and disruption of mitochondrial membrane potential.

CONCLUSION

Phb1 may contribute to maintaining mitochondrial stability and could play a role in regulating cell proliferation and apoptosis of rat liver cells during LR.

SUMOylation and DeSUMOylation: Prospective therapeutic targets in cancer

The SUMO family is a type of ubiquitin-like protein modification molecule. Its protein modification mechanism is similar to that of ubiquitination: both involve modifier-activating enzyme E1, conjugating enzyme E2 and substrate-specific ligase E3. However, polyubiquitination can lead to the degradation of substrate proteins, while poly-SUMOylation only leads to the degradation of substrate proteins through the proteasome pathway after being recognized by ubiquitin as a signal factor. There are currently five reported subtypes in the SUMO family, namely SUMO1-5. As a reversible dynamic modification, intracellular sentrin/SUMO-specific proteases (SENPs) mainly regulate the reverse reaction pathway of SUMOylation. The SUMOylation modification system affects the localization, activation and turnover of proteins in cells and participates in regulating most nuclear and extranuclear molecular reactions. Abnormal expression of proteins related to the SUMOylation pathway is commonly observed in tumors, indicating that this pathway is closely related to tumor occurrence, metastasis and invasion. This review mainly discusses the composition of members in the protein family related to SUMOylation pathways, mutual connections between SUMOylation and other post-translational modifications on proteins as well as therapeutic drugs developed based on these pathways.

Modified rougan decoction attenuates hepatocyte apoptosis through ameliorating mitochondrial dysfunction by upregulated SIRT1/PGC-1α signaling pathway

The modified rougan decoction (MRGD) compound formula has been proven a certain ability to relieve lipopolysaccharide-enrofloxacin (LPS-ENR)-induced liver oxidant injury in chickens. Recent advances have shown that mitochondrial dysfunction affects the development of many diseases, leading to increased interest in exploring its effects. Using LPS-ENR-injured in vivo and in vitro to further evaluate the effects of MRGD on mitochondrial structure and function, and emphasized further investigation of its molecular mechanism. After LPS-ENR treatment, the levels of inflammation and apoptosis markers were increased, along with higher mitochondrial injury. Results showed that MRGD reduced inflammatory factors expression and inhibited the nuclear translocation of NF-κB P65, reducing the inflammatory response in vivo and in vitro. Additionally, MRGD pretreatment inhibited mitochondrial dysfunction, mitochondrial oxidative stress, and mitochondrial pathway apoptosis by maintaining mitochondrial structure and function. Moreover, treatment with the inhibitor EX527 showed that MRGD promoted mitochondrial biogenesis ability through the SIRT1/PGC-1α pathway and interfered with mitochondrial dynamics, and activate Nrf2. In summary, MRGD played a key role in promoting mitochondrial function and thus alleviating hepatocyte apoptosis in vivo and in vitro at least in part.

Liquiritigenin Confers Liver Protection by Enhancing NRF2 Signaling through Both Canonical and Non-canonical Signaling Pathways

Oxidative stress plays a critical role in drug-induced liver injury. In recent years, liquiritigenin (LQ), a natural flavonoid distributed in Glycyrrhizae Radix et Rhizoma (Gan Cao), shows protective effects against oxidative hepatotoxicity. However, the underlying mechanism remains unclear. In this study, we mainly investigated the role of NRF2, a core transcription factor in oxidative stress, in LQ-induced hepatoprotection. Our results indicated that the function of LQ to eliminate reactive oxygen species in liver cells was dependent on NRF2 activation. Both a canonical signaling pathway and a non-canonical signaling pathway are involved in LQ-induced NRF2 activation. LQ induced NRF2 activation in a KEAP1-C151-dependent manner partially. Meanwhile, LQ led to the blockage of autophagic flux and upregulation of p62, which competitively bound with KEAP1 and conferred NRF2 activation in a KEAP1-C151-independent manner. Totally, our study reveals a novel molecular mechanism underlying the hepatoprotection of LQ, providing a new insight into the pathogenesis and therapeutic strategy of oxidative liver injury.

Alcohol and the mechanisms of liver disease

Alcoholic liver disease (ALD), which is a leading cause of morbidity and mortality worldwide, covers a large spectrum of liver injuries ranging from simple steatosis to steatohepatitis, advanced fibrosis, cirrhosis, and hepatocellular carcinoma. The pathogenesis of ALD includes genetic and epigenetic alterations, oxidative stress, acetaldehyde-mediated toxicity and cytokine and chemokine-induced inflammation, metabolic reprogramming, immune damage, and dysbiosis of the gut microbiota. This review discusses the progress in the pathogenesis and molecular mechanism of ALD, which could provide evidence for further research on the potential therapeutic strategies targeting these pathways.

Augmenter of Liver Regeneration Monoclonal Antibody Promotes Apoptosis of Hepatocellular Carcinoma Cells

BACKGROUND AND AIMS

Hepatocellular carcinoma (HCC) is one of the most common types of cancer, often resulting in death. Augmenter of liver regeneration (ALR), a widely expressed multifunctional protein, has roles in liver disease. In our previous study, we reported that ALR knockdown inhibited cell proliferation and promoted cell death. However, there is no study on the roles of ALR in HCC.

METHODS

We used in vitro and in vivo models to investigate the effects of ALR in HCC as well as its mechanism of action. We produced and characterized a human ALR-specific monoclonal antibody (mAb) and investigated the effects of the mAb in HCC cells.

RESULTS

The purified ALR-specific mAb matched the predicted molecular weight of IgG heavy and light chains. Thereafter, we used the ALR-specific mAb as a therapeutic strategy to suppress tumor growth in nude mice. Additionally, we assessed the proliferation and viability of three HCC cell lines, Hep G2, Huh-7, and MHC97-H, treated with the ALR-specific mAb. Compared with controls, tumor growth was inhibited in mice treated with the ALR-specific mAb at 5 mg/kg, as shown by hematoxylin and eosin staining and terminal deoxynucleotidyl transferase dUTP nick end labeling. Simultaneous treatment with the ALR-specific mAb and adriamycin promoted apoptosis, whereas treatment with the ALR-specific mAb alone inhibited cell proliferation.

CONCLUSIONS

The ALR-specific mAb might be a novel therapy for HCC by blocking extracellular ALR.

Impact of liver volumetric regeneration on survival outcomes in patients with hepatocellular carcinoma after major hepatectomy

PURPOSE

Prognostic value of liver volumetric regeneration (LVR) in patients with hepatocellular carcinoma (HCC) who undergo major hepatectomy remains unknown. The aim of this study was to investigate the impact of LVR on long-term outcomes in these patients.

METHODS

Data of 399 consecutive patients with HCC who underwent major hepatectomy between 2000 to 2018 were retrieved from a prospectively maintained institutional database. The LVR-index was defined as the relative increase in liver volume from 7 days to 3 months (RLV3m/RLV7d, where RLV3m and RLV7d is the remnant liver volume around 3 months and postoperative 7 days after surgery). The optimal cut-off value was determined using the median value of LVR-index.

RESULTS

A total of 131 patients were eligible in this study. The optimal cut off value of LVR-index was 1.194. The 1-, 3-, 5- and 10-year overall survival (OS) rate of patients in the high LVR-index group were significantly better compared to those in the low LVR-index group (95.5%, 84.8%, 75.4% and 49.1% vs. 95.4%, 70.2%, 56.4%, and 19.9%, p = 0.002). Meanwhile, there was no significant difference with regards to time to recurrence between the two groups (p = 0.607). Significance of LVR-index for OS was retained after adjusting for known prognostic factors (p = 0.002).

CONCLUSION

In patients with HCC undergoing major hepatectomy, LVR-index may serve as a prognostic indicator for OS.

Interleukin-1ß Attenuates Expression of Augmenter of Liver Regeneration (ALR) by Regulating HNF4α Independent of c-Jun

Inflammasomes and innate immune cells have been shown to contribute to liver injury, thereby activating Kupffer cells, which release several cytokines, including IL-6, IL-1ß, and TNFα. Augmenter of liver regeneration (ALR) is a hepatotropic co-mitogen that was found to have anti-oxidative and anti-apoptotic properties and to attenuate experimental non-alcoholic fatty liver disease (NAFLD) and cholestasis. Additionally, hepatic ALR expression is diminished in patients with NAFLD or cholestasis, but less is known about the mechanisms of its regulation under these conditions. Therefore, we aimed to investigate the role of IL-1ß in ALR expression and to elucidate the molecular mechanism of this regulation in vitro. We found that ALR promoter activity and mRNA and protein expression were reduced upon treatment with IL-1ß. Early growth response protein-1 (Egr-1), an ALR inducer, was induced by IL-1ß but could not activate ALR expression, which may be attributed to reduced Egr-1 binding to the ALR promoter. The expression and nuclear localization of hepatocyte nuclear factor 4 α (HNF4α), another ALR-inducing transcription factor, was reduced by IL-1ß. Interestingly, c-Jun, a potential regulator of ALR and HNF4α, showed increased nuclear phosphorylation levels upon IL-1ß treatment but did not change the expression of ALR or HNF4α. In conclusion, this study offers evidence regarding the regulation of anti-apoptotic and anti-oxidative ALR by IL-1ß through reduced Egr-1 promoter binding and diminished HNF4α expression independent of c-Jun activation. Low ALR tissue levels in NAFLD and cholestatic liver injury may be caused by IL-1ß and contribute to disease progression.

A Multi-Omics Analysis of NASH-Related Prognostic Biomarkers Associated with Drug Sensitivity and Immune Infiltration in Hepatocellular Carcinoma

Background: Nonalcoholic steatohepatitis (NASH)-driven hepatocellular carcinoma (HCC) is becoming a major health-related problem. The exploration of NASH-related prognostic biomarkers and therapeutic targets is necessary. Methods: Data were downloaded from the GEO database. The "glmnet" package was used to identify differentially expressed genes (DEGs). The prognostic model was constructed by the univariate Cox and LASSO regression analyses. Validation of the expression and prognosis by immunohistochemistry (IHC) in vitro. Drug sensitivity and immune cell infiltration were analyzed by CTR-DB and ImmuCellAI. Results: We constructed a prognostic model that identified the NASH-related gene set (DLAT, IDH3B, and MAP3K4), which was validated in a real-world cohort. Next, seven prognostic transcription factors (TFs) were identified. The prognostic ceRNA network included three mRNAs, four miRNAs, and seven lncRNAs. Finally, we found that the gene set was associated with drug response which was validated in six clinical trial cohorts. Moreover, the expression level of the gene set was inversely correlated with CD8 T cell infiltration in HCC. Conclusions: We established a NASH-related prognostic model. Upstream transcriptome analysis and the ceRNA network provided clues for mechanism exploration. The mutant profile, drug sensitivity, and immune infiltration analysis further guided precise diagnosis and treatment strategies.