Afzelin ameliorates D-galactosamine and lipopolysaccharide-induced fulminant hepatic failure by modulating mitochondrial quality control and dynamics

Exploring the Comprehensive Neuroprotective and Anticancer Potential of Afzelin

Neurodegenerative diseases (Alzheimer's disease, Parkinson's disease, Huntington's disease, and others) and cancer, seemingly disparate in their etiology and manifestation, exhibit intriguing associations in certain cellular and molecular processes. Both cancer and neurodegenerative diseases involve the deregulation of cellular processes such as apoptosis, proliferation, and DNA repair and pose a significant global health challenge. Afzelin (kaempferol 3-O-rhamnoside) is a flavonoid compound abundant in various plant sources. Afzelin exhibits a diverse range of biological activities, offering promising prospects for the treatment of diseases hallmarked by oxidative stress and deregulation of cell death pathways. Its protective potential against oxidative stress is also promising for alleviating the side effects of chemotherapy. This review explores the potential therapeutic implications of afzelin, including its capacity to mitigate oxidative stress, modulate inflammation, and promote cellular regeneration in neurodegenerative and cancer diseases.

A study for quality evaluation of Lysimachiae herba from different origins based on fingerprint-activity relationship modeling and multi-component content determination

ETHNOPHARMACOLOGICAL RELEVANCE

Lysimachiae Herba (LH), called Jinqiancao in Chinese, is a commonly used traditional Chinese medicine in clinical practice. Doctors in the Qing Dynasty recorded that it tastes bitter, sour, and slightly cold, and it belongs to the liver, gallbladder, kidney, and bladder meridians. It has the effects of removing dampness and jaundice, eliminating gallstones, and reducing blood stasis. Because of its potent pharmacological effects, it is extensively utilized in the treatment of hepatobiliary and urinary system stones, jaundice, hepatitis, and cholecystitis. Although LH is included in "Sichuan authentic Chinese herbal medicine records", the quality of it from different origins still lacks reliable evaluation methods, which is difficult to reflect the high quality of LH from Sichuan.

AIMS OF THE STUDY

This study aimed to establish a fingerprint-activity relationship model between the fingerprint of LH and its protective effect on cholestatic liver injury, and to evaluate the quality of LH from Sichuan and Guizhou by multivariate statistical analysis.

MATERIALS AND METHODS

20 batches of LH samples were collected from Sichuan and Guizhou. Characteristic fingerprints of samples were established by UHPLC-Triple TOF-MS/MS and the chemical pattern recognition analysis was carried out by HCA. Then, a rat model of cholestatic liver injury was established by intragastric administration of ANIT. Combined with the common peak information of fingerprint and pharmacodynamic index results, GCA and BCA were used to screen the efficacy markers. Finally, based on UHPLC-QTRAP-MS/MS, the content of efficacy markers was simultaneously determined, and the overall quality of LH from two origins was evaluated by PCA and TOPSIS.

RESULTS

In the fingerprint of 20 batches of LH, 15 common peaks were identified in the negative ion mode, and the similarity was between 0.887 and 0.981. Pharmacological results showed that, compared with the control group, the content of AST, ALT, ALP, TBA, TBIL, and MDA in serum increased, and the content of GSH and SOD activity decreased after 48 h of ANIT administration. In addition, compared to the model group, different doses of LH from the two origins could decrease the serum levels of AST, ALT, ALP, TBA, TBIL, and MDA, raise the levels of GSH and SOD activity, reduce the infiltration range of inflammatory cells, and improve the cholestatic liver injury in rats. Among them, the pharmacodynamic indices of the SCHD group were significantly better. GCA and BCA showed that a total of 7 constituents related to the efficacy were screened, which were proanthocyanidin B1, ferulic acid, hyperoside, astragalin, nicotiflorin, afzelin, and kaempferol. Besides, the content of 7 active constituents in samples from Sichuan was higher than that from Guizhou, indicating that the quality of samples from Sichuan may be better, consistent with the result of the pharmacological experiment.

CONCLUSION

The quality and efficacy of LH from different origins were stable, and all of them had protective effects on cholestatic liver injury in rats. The method established in this study is accurate and reliable, and it can be used to comprehensively evaluate the internal quality of LH.

Liver metabolomics reveals potential mechanism of Jieduan-Niwan formula against acute-on-chronic liver failure (ACLF) by improving mitochondrial damage and TCA cycle

BACKGROUND

Acute-on-chronic liver failure (ACLF) is a refractory disease with high mortality, which is characterized by a pathophysiological process of inflammation-related dysfunction of energy metabolism. Jieduan-Niwan formula (JDNWF) is a eutherapeutic Chinese medicine formula for ACLF. However, the intrinsic mechanism of its anti-ACLF effect still need to be studied systematically.

PURPOSE

This study aimed to investigate the mechanism of JDNWF against ACLF based on altered substance metabolic profile in ACLF the expression levels of related molecules.

MATERIALS AND METHODS

The chemical characteristics of JDNWF were characterized using ultra performance liquid chromatography (UPLC) coupled with triple quadrupole mass spectrometry. Wistar rats subjected to a long-term CCL4 stimulation followed by a combination of an acute attack with LPS/D-GalN were used to establish the ACLF model. Liver metabolites were analyzed by LC-MS/MS and multivariate analysis. Liver function, coagulation function, histopathology, mitochondrial metabolic enzyme activity and mitochondrial damage markers were evaluated. The protein expression of mitochondrial quality control (MQC) was investigated by western blot.

RESULTS

Liver function, coagulation function, inflammation, oxidative stress and mitochondrial enzyme activity were significantly improved by JDNWF. 108 metabolites are considered as biomarkers of JDNWF in treating ACLF, which were closely related to TCA cycle. It was further suggested that JDNWF alleviated mitochondrial damage and MQC may be potential mechanism of JDNWF improving mitochondrial function.

CONCLUSIONS

Metabolomics revealed that TCA cycle was impaired in ACLF rats, and JDNWF had a regulatory effect on it. The potential mechanism may be improving the mitochondrial function through MQC pathway, thus restoring energy metabolism.

Afzelin induces immunogenic cell death against lung cancer by targeting NQO2

BACKGROUND

Lung cancer is one of the most common malignant cancers worldwide. Previous studies have shown that Afzelin, a flavonoid, possesses anticancer activity. The aim of this study was to explore Afzelin's effect on lung cancer cells and delineate potential anti-cancer mechanism.

METHODS

The effect of Afzelin on cell viability, proliferation, and apoptosis of lung cancer cells i.e., A549 and H1299 cells, was studied. The targets for Afzelin in lung cancer were predicted using SwissTargetPrediction, Next, the GO analysis and pathway enrichment were analyzed using String. For in vitro studies, the overexpression plasmid of NQO2, the identified target of Afzelin, was transfected into Afzelin-treated cells to verify the regulatory role of Afzelin on its target and signaling pathway.

RESULTS

In in vitro studies, Afzelin markedly inhibited cell viability, proliferation, and raised apoptotic rate of A549 and H1299 cells. In addition, Afzelin activated endoplasmic reticulum (ER) stress and increased ATP, HMGB1, and CRT levels in lung cancer cells, indicating that Afzelin induced immunogenic cell death (ICD). SwissTargetPrediction identified NQO2 as a target of Afzelin. Further, Afzelin markedly inhibited NQO2 protein expression and in turn, overexpression of NQO2 attenuated the effect of Afzelin on A549 and H1299 cells.

CONCLUSION

Afzelin inhibits lung cancer progression by targeting NQO2, in turn, activating ER stress and inducing ICD.

Afzelin protects against doxorubicin-induced cardiotoxicity by promoting the AMPKα/SIRT1 signaling pathway

BACKGROUND

Doxorubicin (DOX), a chemotherapeutic drug, could relieve the progressions of various diseases. However, its clinical application is limited due to its cardiotoxicity. This study aimed to investigate the effects of afzelin (a flavonol glycoside found in Houttuynia cordata) on the cardiotoxicity induced by DOX.

METHODS

In ex-vivo, H9C2 cells were incubated with 20, 40, or 80 μM afzelin for 12 h, followed by the treatment with 1 μM DOX for 12 h. In vivo, C57BL/6 J mice were intraperitoneally injected with 4 mg/kg/day DOX on days 1, 7, and 14. Meanwhile, starting from day 1, mice were intragastrically administrated with 5 mg/kg/day or 10 mg/kg/day afzelin for 20 days. The cardiac function of mice was evaluated by detecting hemodynamic parameters using the M-mode echocardiography.

RESULTS

DOX decreased the cell survival rate, and elevated apoptotic rate, as well as induced the oxidative stress and mitochondrial dysfunction in H9C2 cells. All these changes were alleviated by afzelin treatment in a concentration-dependent manner. The results were further proven by the mitigation of cardiac injury in vivo, as evidenced by the elevation of fractional shortening, heart weight/tibia length, and the rate of the increase/decrease of left ventricular pressure in mice subjected to DOX-induced cardiotoxicity. Furthermore, afzelin upregulated the expression of p-AMP-activated protein kinase alpha (AMPKα) and sirtuin1 (SIRT1). Dorsomorphin (an AMPKα inhibitor) abrogated the anti-cardiotoxicity effects of afzelin in H9C2 cells induced by DOX.

CONCLUSION

Afzelin protected against DOX-induced cardiotoxicity by promoting the AMPKα/SIRT1 signaling pathway.

Temporospatial pattern of flavonoid metabolites and potential regulatory pathway of PbMYB211-coordinated kaempferol-3-O-rhamnoside biosynthesis in Phoebe bournei

Phoebe is a well-known timber tree species that contains abundant metabolites characterized by flavonoids that are widely used in the pharmaceutical industry. Nevertheless, temporospatial flavonoid metabolism variations substantially impact the Phoebe industry. Thus, a metabolomics analysis was carried out and identified 465 metabolites (102 flavonoids) in P. bournei, revealing distinct distribution patterns among five studied organs, and most of the flavonoids were dominant in the leaves. Furthermore, three kaempferol glycoside derivatives were significantly accumulated in the leaves and showed higher contents in young leaves than in mature leaves and differences between spring and autumn. For instance, greater accumulation of kaempferol-7-O-rhamnoside was detected in spring, whereas higher contents of kaempferol-3-O-arabinofuranoside and kaempferol-3-O-rhamnoside were found in autumn. Integrated metabolomics and transcriptomics identified 20 transcription factors (TFs) and 12 structural genes that participate in kaempferol derivative synthesis and elucidated a potential regulatory mechanism in P. bournei. Of the identified genes, PbMYB211 might contribute significantly to the kaempferol-3-O-rhamnoside content by regulating the target structural gene PbUGT139, as revealed by transient overexpression analysis. Overall, this study illuminated the temporospatial accumulation of flavonoids among different organs, seasons, and developmental stages in P. bournei and elucidated a potential regulatory pathway of kaempferol-3-O-rhamnoside. The results provide important insights into harvest techniques and a theoretical basis for the comprehensive utilization of P. bournei.

Capsaicin protects against septic acute liver injury by attenuation of apoptosis and mitochondrial dysfunction

Capsaicin is the main pungent bioactive constituent in red chili with promising therapeutic properties due to its anti-oxidative and anti-inflammatory effects. No evidence exists on the beneficial effect of capsaicin on apoptosis and mitochondrial function in acute liver injury (ALI) under septic conditions. For inducing septic ALI, lipopolysaccharide (LPS, 50 μg/kg) and d-galactose (D-Gal, 400 mg/kg) was intraperitoneally injected and capsaicin was given orally at 5 or 20 mg/kg. Functional markers of liver function and mitochondrial dysfunction were determined as well as hepatic assessment of apoptotic, oxidative, and inflammatory factors. Capsaicin at the higher dose appropriately decreased serum level of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in addition to reducing hepatic level of malondialdehyde (MDA), reactive oxygen species (ROS), nitrite, NF-kB, TLR4, IL-1β, TNF-α, caspase 3, DNA fragmentation and boosting sirtuin 1, Nrf2, superoxide dismutase (SOD) activity, and heme oxygenase (HO-1). These beneficial effects of capsaicin were associated with reversal and/or improvement of gene expression for pro-apoptotic Bax, anti-apoptotic Bcl2, mitochondrial and metabolic regulators PGC-1α, sirtuin 1, and AMPK, and inflammation-associated factors. Additionally, capsaicin exerted a hepatoprotective effect, as revealed by its reduction of liver histopathological changes. These findings evidently indicate hepatoprotective property of capsaicin under septic conditions that can be attributed to its down-regulation of oxidative and inflammatory processes besides its potential to attenuate mitochondrial dysfunction and apoptosis.

Nutraceutical prospects of Houttuynia cordata against the infectious viruses

The novel enveloped β-coronavirus SARS-CoV-2 (COVID-19) has offered a surprising health challenge all over the world. It develops severe pneumonia leading to acute respiratory distress syndrome (ARDS). Like SARS-COV-2, other encapsulated viruses like HIV, HSV, and influenza have also offered a similar challenge in the past. In this regard, many antiviral drugs are being explored with varying degrees of success to combat the associated pathological conditions. Therefore, upon scientific validation & development, these antiviral phytochemicals can attain a futuristic nutraceutical prospect in managing different encapsulated viruses. Houttuynia cordata (HC) is widely reported for activities such as antioxidant, anti-inflammatory, and antiviral properties. The major antiviral bioactive components of HC include essential oils (methyl n-nonyl ketone, lauryl aldehyde, capryl aldehyde), flavonoids (quercetin, rutin, hyperin, quercitrin, isoquercitrin), and alkaloids (norcepharadione B) & polysaccharides. HC can further be explored as a potential nutraceutical agent in the therapy of encapsulated viruses like HIV, HSV, and influenza. The review listed various conventional and green technologies that are being employed to extract potent phytochemicals with diverse activities from the HC. It was indicated that HC also inhibited molecular targets like 3C-like protease (3CLPRO) and RNA-dependent RNA polymerase (RdRp) of COVID-19 by blocking viral RNA synthesis and replication. Antioxidant and hepatoprotective effects of HC have been evident in impeding complications from marketed drugs during antiviral therapies. The use of HC as a nutraceutical is localized within some parts of Southeast Asia. Further technological advances can establish it as a nutraceutical-based functional food against pathogenic enveloped viruses like COVID 19.

Propitious maneuvering for delivery of the phytopharmaceutical "apocynin" to induced fulminant hepatitis in BALB/c mice: In vitro and in vivo assessments

Apocynin (APO), a specific nicotinamide adenine dinucleotide phosphate-oxidase (NADPH-oxidase, NOX) inhibitor, has recently emerged as a bioactive phytochemical with eminent anti-inflammatory and anti-oxidant activities. To our knowledge, no research has been conducted to fabricate a mucoadhesive nanostructured delivery system of APO that targets the liver. Accordingly, chitosan (CS) surface decorated polymeric nanoparticulate delivery system (PNDS) was victoriously fabricated by double emulsion-solvent evaporation method. Herein, a randomized full 33 factorial design was employed to assess the impact of the independently processing parameters (IPPs) namely; (poly(d,l-lactide-co-glycolide) (PLGA) amount (A)), (polyvinyl alcohol (PVA) concentration (B)), and (CS concentration (C)), on different dependently measured attributes (DMAs). The optimal APO-loaded chitosan-coated poly(d,l-lactide-co-glycolide) nanoparticles (APO-loaded CS-coated PLGA NPs) formula (F19) would be extensively appraised through meticulous in vitro-in vivo studies. Crucially, the results revealed that oral pre-treatment with the optimal formula evoked a prodigious in vivo hepatoprotective efficacy against lipopolysaccharide (LPS)/D-(+)-galactosamine (D-GalN) induced fulminant hepatitis (FH) in BALB/c mice when compared with pure APO, uncoated F19, and plain NPs (P NPs) pretreated groups. In conclusion, APO-loaded CS-coated PLGA NPs could be considered as a promising oral mucoadhesive phytopharmaceutical PNDS to open new prospects for therapeutic intervention in inflammatory based liver diseases.

Pharmacological Effects of Houttuynia cordata Thunb (H. cordata): A Comprehensive Review

Houttuynia cordata Thunb (H. cordata) is a rhizomatous, herbaceous, and perennial plant widely distributed in Asia. It has multiple chemical constituents, such as alkaloids, essential oils, phenolic acids, and flavonoids used against various health problems. The essential oils and flavonoids are the main components of H. cordata that play an essential role in disease treatment and traditional health care. Moreover, the leaves and stems of H. cordata have a long medicinal history in China. In addition, H. cordata is used against several health issues, such as cold, cough, fever, pneumonia, mumps, and tumors, due to its anti-inflammatory, anti-bacterial, anti-viral, anti-oxidant, and anti-tumor effects. It protects organs due to its anti-inflammatory activity. H. cordata regulates immunity by enhancing immune barriers of the oral cavity, vagina, and gastrointestinal tract, and shows broad-spectrum activity against liver, lung, breast, and colon tumors. However, there are some gaps to be filled to understand its pathways and mechanisms. Mechanisms such as its interaction with cells, cell membranes, and various drugs are important. Studies in relation to the blood–brain barrier, lipophilicity, cAMP signaling, and skin permeability, including pharmaceutical effects, will be very useful. This review includes the biological and pharmacological activities of H. cordata based on up-to-date research.

Evaluation of the chemical profile from four germplasms sources of Pruni Semen using UHPLC-LTQ-Orbitrap-MS and multivariate analysis

Pruni Semen, the seed of several unique Prunus plants, is a traditional purgative herbal material. To determine the authentic sources of Pruni Semen, 46 samples from four species were collected and analyzed. Ten compounds including multiflorin A (Mul A), a notable purative compound, were isolated and identified by chemical separation and nuclear magnetic resonance spectroscopy. Seventy-six communal components were identified by ultra-high performance liquid chromatography with linear ion trap-quadrupole Orbitrap mass spectrometry, and acetyl flavonoid glycosides were recognized as characteristic constituents. The flavonoids were distributed in the seed coat and cyanogenic glycosides in the kernel. Based on this, methods for identifying Pruni Semen from different sources were established using chemical fingerprinting, quantitative analysis of the eight principal compounds, hierarchical cluster analysis, principal component analysis, and orthogonal partial least squares discriminant analysis. The results showed that the samples were divided into two categories: one is the small seeds from Prunus humilis (Ph) and Prunus japonica (Pj), and the other is the big seeds from Prunus pedunculata (Pp) and Prunus triloba (Pt). The average content of Mul A was 3.02, 6.93, 0.40, and 0.29 mg/g, while the average content of amygdalin was 18.5, 17.7, 31.5, and 30.9 mg/g in Ph, Pj, Pp, and Pt, respectively. All the above information suggests that small seeds might be superior sources of Pruni Semen. This is the first comprehensive report on the identification of chemical components in Pruni Semen from different species.

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Chemical constituents of Pruni semen from four Prunus species were compared.

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Acetyl flavonoid glycosides were identified as the characteristic components.

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Flavonoids were present in the seed coat and cyanogenic glycosides in the kernel.

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The content of acetyl flavonoid in small seeds is significant higher than those in big ones.

Uptake and Transport of Naringenin and Its Antioxidant Effects in Human Intestinal Epithelial Caco-2 Cells

Naringenin, a flavanone, has been reported for a wide range of pharmacological activities. However, there are few reports on the absorption, transport and antioxidant effects of naringenin. The study was to explore the uptake, transport and antioxidant effects of naringenin in vitro. Cell transmembrane resistance, lucifer yellow transmission rate, and alkaline phosphatase activity were used to evaluate the successful construction of cell model. The results showed that the absorption and transport of naringenin by Caco-2 cells were time- and concentration-dependent. Different temperatures (37 and 4°C) had a significant effect on the uptake and transport of naringenin. Verapamil, potent inhibitor of P-glycoprotein, significantly inhibit naringenin transport in Caco-2 cells. The results revealed that naringenin was a moderately absorbed biological macromolecule and can penetrate Caco-2 cells, mainly mediated by the active transport pathway involved in P-glycoprotein. At the same time, naringenin pretreatment could significantly increase the viability of H₂O₂-induced Caco-2 cells. Twenty four differential metabolites were identified based on cellular metabolite analysis, mainly including alanine, aspartate and glutamate metabolism, histidine metabolism, taurine and hypotaurine metabolism, pyruvate metabolism, purine metabolism, arginine biosynthesis, citrate cycle, riboflavin metabolism, and D-glutamine and D-glutamate metabolism. We concluded that the transport of naringenin by Caco-2 cells is mainly involved in active transport mediated by P-glycoprotein and naringenin may play an important role in oxidative stress-induced intestinal diseases.

Kaempferol 3-Rhamnoside on Glutamate Release from Rat Cerebrocortical Nerve Terminals Involves P/Q-Type Ca2+ Channel and Ca2+/Calmodulin-Dependent Protein Kinase II-Dependent Pathway Suppression

Excess synaptic glutamate release has pathological consequences, and the inhibition of glutamate release is crucial for neuroprotection. Kaempferol 3-rhamnoside (KR) is a flavonoid isolated from Schima superba with neuroprotective properties, and its effecton the release of glutamate from rat cerebrocortical nerve terminals was investigated. KR produced a concentration-dependent inhibition of 4-aminopyridine (4-AP)-evoked glutamate release with half-maximal inhibitory concentration value of 17 µM. The inhibition of glutamate release by KR was completely abolished by the omission of external Ca²⁺ or the depletion of glutamate in synaptic vesicles, and it was unaffected by blocking carrier-mediated release. In addition, KR reduced the 4-AP-evoked increase in Ca²⁺ concentration, while it did not affect 4-AP-evoked membrane potential depolarization. The application of selective antagonists of voltage-dependent Ca²⁺ channels revealed that the KR-mediated inhibition of glutamate release involved the suppression of P/Q-type Ca²⁺ channel activity. Furthermore, the inhibition of release was abolished by the calmodulin antagonist, W7, and Ca²⁺/calmodulin-dependent protein kinase II (CaMKII) inhibitor, KN62, but not by the protein kinase A (PKA) inhibitor, H89, or the protein kinase C (PKC) inhibitor, GF109203X. We also found that KR reduced the 4-AP-induced increase in phosphorylation of CaMKII and its substrate synapsin I. Thus, the effect of KR on evoked glutamate release is likely linked to a decrease in P/Q-type Ca²⁺ channel activity, as well as to the consequent reduction in the CaMKII/synapsin I pathway.

Ingredients with anti-inflammatory effect from medicine food homology plants

Inflammation occurs when the immune system responses to external harmful stimuli and infection. Chronic inflammation induces various diseases. A variety of foods are prescribed in the traditional medicines of many countries all over the world, which gave birth to the concept of medicine food homology. Over the past few decades, a number of secondary metabolites from medicine food homology plants have been demonstrated to have anti-inflammatory effects. In the present review, the effects and mechanisms of the medicine food homology plants-derived active components on relieving inflammation and inflammation-mediated diseases were summarized and discussed. The information provided in this review is valuable to future studies on anti-inflammatory ingredients derived from medicine food homology plants as drugs or food supplements.

Exosomes from adipose-derived mesenchymal stem cells alleviate liver ischaemia reperfusion injury subsequent to hepatectomy in rats by regulating mitochondrial dynamics and biogenesis

Hepatic ischaemia reperfusion injury (HIRI) is a major factor leading to liver dysfunction after liver resection and liver transplantation. Adipose-derived mesenchymal stem cells (ADSCs) have potential therapeutic effects on HIRI. Exosomes derived from ADSCs (ADSCs-exo) have been widely studied as an alternative of ADSCs therapy. Thus, the aim of this study was to evaluate the potential protective effect and related mechanism of ADSCs-exo on HIRI subsequent to hepatectomy. Rats were randomly divided into four groups: Sham, I30R+PH, ADSCs and ADSCs-exo group. After 24 h of reperfusion, liver and serum of the rats were immediately collected. ADSCs-exo improved liver function, inhibited oxidative stress and reduced apoptosis of hepatocytes in HIRI subsequent to hepatectomy in rats. ADSCs-exo significantly promoted the recovery of mitochondrial function, markedly increased the content of ATP in the liver tissue, and improved the ultrastructure of mitochondria in hepatocytes. Moreover, ADSCs-exo significantly increased the expression of OPA-1, MFN-1 and MFN-2 proteins related to mitochondrial fusion, while DRP-1 and Fis-1 mRNA and protein expression associated with mitochondrial fission were significantly decreased after the treatment with ADSCs-exo. In addition, ADSCs-exo significantly increased the expression of PGC-1α, NRF-1 and TFAM genes and proteins related to mitochondrial biogenesis. ADSCs-exo improves liver function induced by HIRI subsequent to hepatectomy in rats and maintains mitochondrial homeostasis by inhibiting mitochondrial fission, promoting mitochondrial fusion and promoting mitochondrial biogenesis. Therefore, ADSCs-exo may be considered as a potential promising alternative to ADSCs in the treatment of HIRI subsequent to hepatectomy.

Network Pharmacology to Explore the Molecular Mechanisms of Prunella vulgaris for Treating Hashimoto's Thyroiditis

Purpose:Prunella vulgaris (PV), a traditional Chinese medicine, has been used to treat patients with thyroid disease for centuries in China. The purpose of the present study was to investigate its bioactive ingredients and mechanisms against Hashimoto’s thyroiditis (HT) using network pharmacology and molecular docking technology to provide some basis for experimental research.

Methods: Ingredients of the PV formula were retrieved from the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database. Additionally, HT-related genes were retrieved from the UniProt and GeneCards databases. Cytoscape constructed networks for visualization. A protein–protein interaction (PPI) network analysis was constructed, and a PPI network was built using the Search Tool for the Retrieval of Interacting Genes (STRING) database. These key targets of PV were enriched and analyzed by molecular docking verification, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment.

Results: The compound–target network included 11 compounds and 66 target genes. Key targets contained Jun proto-oncogene (JUN), hsp90aa1.1 (AKI), mitogen-activated protein kinase 1 (MAPK1), and tumor protein p53 (TP53). The main pathways included the AGE-RAGE signaling pathway, the TNF signaling pathway, the PI3K–Akt signaling pathway, and the mitogen-activated protein kinase signaling pathway. The molecular docking results revealed that the main compound identified in the Prunella vulgaris was luteolin, followed by kaempferol, which had a strong affinity for HT.

Conclusion: Molecular docking studies indicated that luteolin and kaempferol were bioactive compounds of PV and might play an essential role in treating HT by regulating multiple signaling pathways.

Deubiquitinating enzyme USP30 negatively regulates mitophagy and accelerates myocardial cell senescence through antagonism of Parkin

Cell senescence is associated with age-related pathological changes. Increasing evidence has revealed that mitophagy can selectively remove dysfunctional mitochondria. Overexpression of ubiquitin-specific protease 30 (USP30) has been documented to influence mitophagy and deubiquitination of mitochondrial Parkin substrates. This study was conducted to evaluate the roles of USP30 and Parkin in myocardial cell senescence and mitophagy. Initially, myocardial cells were isolated from neonatal SD rats and subjected to d-gal treatment to induce cell senescence, after which the effects of d-gal on mitochondria damage, ROS production, cell senescence, and mitophagy were assessed. The myocardial cells were infected with lentiviruses bearing overexpression plasmids or shRNA targeting Parkin or USP30 to elucidate the effects of Parkin and USP30 on d-gal-induced mitophagy damage and cell senescence. Finally, aging was induced in rats by subcutaneous injection of d-gal to determine the role of Parkin and USP30 on cell senescence in vivo. d-gal was found to trigger mitochondria damage, ROS production, and cell senescence in myocardial cells. The overexpression of Parkin or silencing of USP30 reduced d-gal-induced mitochondrial damage and relieved d-gal-induced myocardial cell senescence. Moreover, the in vivo experiments validated that either elevation of Parkin or silencing USP30 could alleviate d-gal-induced myocardial cell senescence in rats. Silencing USP30 alleviates d-gal-induced mitochondrial damage and consequently suppresses myocardial cell senescence by activating Parkin. Our study highlights the potential of USP30 as a novel target against myocardial cell senescence.

Dexmedetomidine ameliorates endotoxin-induced acute lung injury in vivo and in vitro by preserving mitochondrial dynamic equilibrium through the HIF-1a/HO-1 signaling pathway

Increasing lines of evidence identified that dexmedetomidine (DEX) exerted protective effects against sepsis-stimulated acute lung injury via anti-inflammation, anti-oxidation and anti-apoptosis. However, the mechanisms remain unclear. Herein, we investigated whether DEX afforded lung protection by regulating the process of mitochondrial dynamics through the HIF-1a/HO-1 pathway in vivo and in vitro. Using C57BL/6J mice exposed to lipopolysaccharide, it was initially observed that preemptive administration of DEX (50μg/kg) alleviated lung pathologic injury, reduced oxidative stress indices (OSI), improved mitochondrial dysfunction, upregulated the expression of HIF-1α and HO-1, accompanied by shifting the dynamic course of mitochondria into fusion. Moreover, HO-1-knockout mice or HO-1 siRNA transfected NR8383 cells were pretreated with HIF-1α stabilizer DMOG and DEX to validate the effect of HIF-1a/HO-1 pathway on DEX-mediated mitochondrial dynamics in a model of endotoxin-induced lung injury. We found that pretreatment with DEX and DMOG distinctly relieved lung injury, decreased the levels of mitochondrial ROS and mtDNA, reduced OSI, increased nuclear accumulation of HIF-1a and HO-1 protein in wild type mice but not HO-1 KO mice. Similar observations were recapitulated in NC siRNA transfected NR8383 cells after LPS stimulation but not HO-1 siRNA transfected cells. Concertedly, DEX reversed the impaired mitochondrial morphology in LPS stimulated-wild type mice or NC siRNA transfected NR8383 cells, upregulated the expression of mitochondrial fusion protein, while downregulated the expression of fission protein in HIF-1a/HO-1 dependent pathway. Altogether, our data both in vivo and in vitro certified that DEX treatment ameliorated endotoxin-induced acute lung injury by preserving the dynamic equilibrium of mitochondrial fusion/fission through the regulation of HIF-1a/HO-1 signaling pathway.

Selonsertib, a potential drug for liver failure therapy by rescuing the mitochondrial dysfunction of macrophage via ASK1-JNK-DRP1 pathway

Background

Acute liver failure (ALF) is associated with a high mortality rate, and there are still no effective treatments except liver transplantation and artificial liver therapies. This study aimed to determine the effects, therapeutic window and mechanisms of selonsertib, a selective inhibitor of ASK1, for ALF therapy.

Results

Lipopolysaccharide and d-galactosamine (LPS/GalN) were used to simulate ALF. We found that selonsertib pretreatment significantly ameliorated ALF, as determined by reduced hepatic necrosis and serum alanine aminotransferase, aspartate aminotransferase and inflammatory cytokine levels. However, selonsertib is only effective early after LPS/GalN administration, and the limited therapeutic window is related to the activation and mitochondrial translocation of JNK and DRP1. Further experiments revealed that selonsertib could alleviate LPS-induced mitochondrial damage in macrophages by evaluating the mitochondrial membrane potential and mitochondrial permeability transition pore opening in macrophages. Selonsertib also suppressed the release of inflammatory cytokines from macrophages by reducing DRP1-mediated mitochondrial dysfunction, which was confirmed by using mdivi, a specific DRP1 inhibitor.

Conclusions

Selonsertib protected against LPS/GalN-induced ALF by attenuating JNK-mediated DRP1 mitochondrial translocation and then rescuing mitochondrial damage in macrophages and may have therapeutic potential for early ALF patients.

Diuretic and Renal Protective Effect of Kaempferol 3-O-Alpha-l-rhamnoside (Afzelin) in Normotensive and Hypertensive Rats

Our previous study showed that kaempferitrin, the main flavonoid from Bauhinia forficata Link leaves, induces diuresis and saluresis when orally given to rats. Since afzelin (AFZ) and kaempferol (KFL) are active compounds from the biometabolism of kaempferitrin, the diuretic and renal protective properties of these two compounds were evaluated. While the acute treatment with AFZ evoked a diuretic action associated with an increase in Cl^- excretion and a Ca²⁺-sparing effect, KFL did not present any activity. The pretreatment with a muscarinic receptor blocker or with an inhibitor of the cyclooxygenase fully avoided AFZ-induced diuresis. AFZ also induced a prolonged (7-day treatment) diuretic effect in normotensive (NTR) and hypertensive rats (SHR), with an increase of urinary Na⁺ and Cl^- excretion, while it decreased the elimination of Ca²⁺. AFZ was able to decrease ROS and nitrite generation on kidney homogenates in comparison with the SHR group treated with the vehicle, as well as mitigated the changes in the renal corpuscle region (glomerulus and Bowman's capsule). Moreover, AFZ significantly reduced calcium oxalate crystal formation in urine, with inhibition rates of 41% for the NTR and 92% for the SHR group. Taken together, this study shows that AFZ exerts acute and prolonged diuretic effects plus protective renal properties.

Histone deacetylase 6 inhibitor ACY1215 ameliorates mitochondrial dynamic and function injury in hepatocytes by activating AMPK signaling pathway in acute liver failure mice

Acute liver failure (ALF) is often accompanied by dynamic and functional disorders of mitochondria in hepatocytes. The histone deacetylase 6 inhibitor Rocilinostat (ACY1215) has a hepatoprotective effect. However, its protective effect on mitochondria of hepatocytes and its related mechanisms in ALF remain unknown. The purpose of the present study was to elucidate the protective effect of ACY1215 on mitochondrial of hepatocytes in ALF by regulating AMPK signaling pathway. LPS and D-Gal were used to induce ALF model in C57BL/6 mice. D-Gal and TNF-α were applied in L02 cells as model group. ACY1215 was administered to the mice or culture cells before the model' s establishment as ACY1215 group. The normal group in mice and L02 cells was not given any drug intervention. ACY1215 improves liver histological and functional changes in ALF model mice. Compared with normal group, the expression of p-AMPK and p-ACC proteins was decreased in model group. ACY1215 activated the AMPK signaling pathway with an increase of p-AMPK and p-ACC proteins level in model group. ACY1215 treatment decreased levels of mitochondrial fission proteins DRP1 and FIS1, and enhanced levels of mitochondrial fusion proteins MFN1, MFN2 and OPA1 in models. MtDNA copies in model group was decreased compared with normal group, but ACY1215 elevated the mtDNA copies in models. Mitochondrial respiratory electron transfer chain Complex I-III and citrate synthase (CS) activities in model group were decreased compared with normal group, but ACY1215 treatment enhanced these activities in model group. ACY1215 protects against dynamic disorders and dysfunction of mitochondria in hepatocytes in ALF by activating AMPK signaling pathway.

Melatonin modulates mitophagy, innate immunity and circadian clocks in a model of viral-induced fulminant hepatic failure

The haemorrhagic disease virus (RHDV) is a non‐cultivable virus that promotes in rabbits an acute disease which accomplishes many characteristics of an animal model of fulminant hepatic failure (FHF). Beneficial effects of melatonin have been reported in RHDV‐infected rabbits. This study investigated whether protection against viral‐derived liver injury by melatonin is associated with modulation of mitophagy, innate immunity and clock signalling. Rabbits were experimentally infected with 2 × 10⁴ haemagglutination units of a RHDV isolate and killed at 18, 24 and 30 hours after infection (hpi). Melatonin (20 mg/kg body weight ip) was administered at 0, 12 and 24 hpi. RHDV infection induced mitophagy, with the presence of a high number of mitophagosomes in hepatocytes and increased expression of mitophagy genes. Greater expression of main innate immune intermediaries and inflammasome components was also found in livers with RHDV‐induced FHF. Both mitophagy and innate immunity activation was significantly hindered by melatonin. FHF induction also elicited an early dysregulation in clock signalling, and melatonin was able to prevent such circadian disruption. Our study discloses novel molecular routes contributing to RHDV‐induced damage progression and supports the potential of melatonin as a promising therapeutic option in human FHF.

Crocetin protects against fulminant hepatic failure induced by lipopolysaccharide/D-galactosamine by decreasing apoptosis, inflammation and oxidative stress in a rat model

Fulminant hepatic failure (FHF) is a clinical syndrome characterized by sudden and severe liver dysfunction. Apoptosis and inflammation are essential for the pathogenesis of FHF. Crocetin, the major component present in saffron, has been reported to possess anti-inflammatory and antioxidant functions; however, its role in FHF is poorly understood. The aim of this study was to explore the protective effects of crocetin against lipopolysac§§charide (LPS)/D-galactosamine (D-GalN)-induced FHF and the underlying mechanisms in a rat model. For the in vivo study, rats were assigned to the LPS/D-GalN group or to the crocetin pre-treatment+LPS/D- GalN group. Each group was then further divided according to the different LPS/D-GalN treatment times of 0, 6, 12 or 48 h. The results demonstrated that crocetin pre-treatment efficiently protected against LPS/D-GalN-induced FHF by improving liver tissue morphology, reducing total bilirubin generation and decreasing the activities of alanine transaminase and aspartate aminotransferase. Moreover, crocetin pre-treatment significantly decreased hepatocyte apoptosis, p53 mRNA expression and the expression of proteins in the caspase family and the Bcl-2 pro-apoptotic family following LPS/D-GalN treatment. Furthermore, crocetin also decreased the secretion of pro-inflammatory cytokines in the serum and in the liver via suppression of NF-κB activation, and also suppressed hepatic oxidative stress. In conclusion, crocetin protected against LPS/D-GalN-induced FHF and inhibited apoptosis, inflammation and oxidative stress. The underlying mechanisms may be related to the regulation of apoptotic proteins in the caspase family and the Bcl-2 family, as well as the modulation of NF-κB expression. Therefore, crocetin may be used as a novel therapy for preventing FHF.

Dynamin-1-Like Protein Inhibition Drives Megamitochondria Formation as an Adaptive Response in Alcohol-Induced Hepatotoxicity

Despite the growing global burden of alcoholic liver diseases, therapeutic options are limited, and novel targets are urgently needed. Accumulating evidence suggests that mitochondria adapt in response to ethanol and formation of megamitochondria in the livers of patients is recognized as a hallmark of alcoholic liver diseases. The processes involved in ethanol-induced hepatic mitochondrial changes, the impact on mitochondria-shaping proteins, and the significance of megamitochondria formation remain unknown. In this study, we investigated the mitochondrial and cellular response to alcohol in hepatoma cell line VL-17A. The mitochondrial architecture rapidly changed after 3 or 14 days of ethanol exposure with double-pronged presentation of hyperfragmentation and megamitochondria, and cell growth was inhibited. Dynamin-1-like protein (Drp1) was identified as the main mediator driving these mitochondrial alterations, and its genetic inactivation was determined to foster megamitochondria development, preserving the capacity of the cells to grow despite alcohol toxicity. The role of Drp1 in mediating megamitochondria formation in mice with liver-specific inactivation of Drp1 was further confirmed. Finally, when these mice were fed with ethanol, the presentation of hepatic megamitochondria was exacerbated compared with wild type fed with the same diet. Ethanol-induced toxicity was also reduced. Our study demonstrates that megamitochondria formation is mediated by Drp1, and this phenomenon is a beneficial adaptive response during alcohol-induced hepatotoxicity.

Molecular mechanism and research progress on pharmacology of traditional Chinese medicine in liver injury

CONTEXT

Liver disease is a common threat to human health, caused by a variety of factors that damage the liver. Recent studies have shown that active ingredients (for example: flavonoids, saponins, acids, phenols, and alkaloids) from Traditional Chinese Medicine (TCM) can have hepatoprotective benefits, which represents an attractive source of drug discovery for treating liver injury.

OBJECTIVE

We reviewed recent contributions on the chemically induced liver injury, immunological liver damage, alcoholic liver injury, and drug-induced liver injury, in order to summarize the research progress in molecular mechanism and pharmacology of TCM, and provides a comprehensive overview of new TCM treatment strategies for liver disease.

MATERIALS AND METHODS

Relevant literature was obtained from scientific databases such as Pubmed, Web of Science. and CNKI databases on ethnobotany and ethnomedicines (from January 1980 to the end of May 2018). The experimental studies involving the antihepatic injury role of the active agents from TCM and the underlying mechanisms were identified. The search terms included 'liver injury' or 'hepatic injury', and 'traditional Chinese medicine', or 'herb'.

RESULTS

A number of studies revealed that the active ingredients of TCM exhibit potential therapeutic benefits against liver injury, while the underlying mechanisms appear to contribute to the regulation of inflammation, oxidant stress, and pro-apoptosis signaling pathways.

DISCUSSION AND CONCLUSIONS

The insights provided in this review will help further exploration of botanical drugs in the development of liver injury therapy via study on the effective components of TCM.

Role of mitophagy regulation by ROS in hepatic stellate cells during acute liver failure

Liver sinusoids serve as the first line of defense against extrahepatic stimuli from the intestinal tract. Hepatic stellate cells (HSCs) are pericytes residing in the perisinusoidal space that integrate cytokine-mediated inflammatory responses in the sinusoids and relay these signals to the liver parenchyma. Oxidative stress has been shown to promote inflammation during acute liver failure (ALF). Whether and how oxidative stress is involved in HSC inflammation during ALF remains unclear. Level of systemic oxidative stress is reflected by superoxide dismutase (SOD). Thus, ALF patients were recruited to investigate the correlation between plasma SOD levels and clinical features. Liver tissues were collected from chronic hepatitis patients by biopsy and from ALF patients who had undergone liver transplantation. SOD2 expression and HSCs activation were investigated by immunohistochemistry. Inflammation, mitophagy, and apoptosis were investigated by immunoblot analysis and flow cytometry in HSCs treated with lipopolysaccharide (LPS) and reactive oxygen species (ROS) donors. The plasma SOD level was significantly increased in patients with ALF compared with those with cirrhosis (444.4 ± 23.58 vs. 170.07 ± 3.52 U/ml, P < 0.01) and was positively correlated with the Model for End-Stage Liver Disease-Na score ( R² = 0.4720, P < 0.01). In vivo observations revealed that SOD2 immunostaining was increased in ALF patients and mice models, and in vitro experiments demonstrated that LPS/ROS promoted inflammation via inhibiting mitophagy. Moreover, the regulation of inflammation was apoptosis independent in HSCs. LPS-induced increases in oxidative stress promote inflammation through inhibiting mitophagy in HSCs during the process of ALF, providing a novel strategy for the treatment of patients with ALF. NEW & NOTEWORTHY Here we demonstrate that the serum superoxide dismutase (SOD) level is significantly increased in patients with acute liver failure (ALF), and, correlated with the Model for End-Stage Liver Disease-Na score, SOD level dropped in the remission stage of ALF. We identify that, in liver tissue from ALF patients and mice models, manganese-dependent SOD was overexpressed, and show lipopolysaccharide/H₂O₂ inhibits mitophagy via reactive oxygen species in hepatic stellate cells (HSCs). We show that inhibited mitophagy promotes inflammation in HSCs, whereas mitophagy inducer rescues HSCs from lipopolysaccharide-induced inflammation.

Anti‑apoptotic effects of human placental hydrolysate against hepatocyte toxicity in vivo and in vitro

Apoptosis and oxidative stress are essential for the pathogenesis of acute liver failure and fulminant hepatic failure. Human placental hydrolysate (hPH) has been reported to possess antioxidant and anti-inflammatory properties. In the present study, the protective effects of hPH against D-galactosamine (D-GalN)- and lipopolysaccharide (LPS)-induced hepatocyte apoptosis were investigated in vivo. In addition, the molecular mechanisms underlying the anti-apoptotic activities of hPH against D-GalN-induced cell death in vitro were examined. Male Sprague-Dawley rats were injected with D-GaIN/LPS with or without the administration of hPH. Rats were sacrificed 24 h after D-GaIN/LPS intraperitoneal injection, and the blood and liver samples were collected for future inflammation and hepatotoxicity analyses. Changes in cell viability, apoptosis protein expression, mitochondrial mass, mitochondrial membrane potential, reactive oxygen species generation, and the levels of proteins and mRNA associated with a protective mechanism were determined in HepG2 cells pretreated with hPH for 2 h prior to D-GalN exposure. The findings suggested that hPH treatment effectively protected against D-GalN/LPS-induced hepatocyte apoptosis by reducing the levels of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, interleukin-6, and tumor necrosis factor-α, and increasing the level of proliferating cell nuclear antigen. It was also found that hPH inhibited the apoptotic cell death induced by D-GalN. hPH activated the expression of antioxidant enzymes, including superoxide dismutase, glutathione peroxidase, and catalase, which were further upregulated by the Kelch-like ECH2-associated protein 1-p62-nuclear factor-erythroid 2-related factor 2 pathway, a component of oxidative stress defense mechanisms. Furthermore, hPH markedly reduced cytosolic and mitochondrial reactive oxygen species and rescued mitochondrial loss and dysfunction through the reduction of damage-regulated autophagy modulator, p53, and C/EBP homologous protein. Collectively, hPH exhibited a protective role in hepatocyte apoptosis by inhibiting oxidative stress and maintaining cell homeostasis. The underlying mechanisms may be associated with the inhibition of endoplasmic reticulum stress and minimization of the autophagy progress.

Therapeutic potentials of Houttuynia cordata Thunb. against inflammation and oxidative stress: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Houttuynia cordata Thunb. (Family: Saururaceae) is an herbaceous perennial plant that grows in moist and shady places. The plant is well known among the people of diverse cultures across Japan, Korea, China and North-East India for its medicinal properties. Traditionally the plant is used for its various beneficial properties against inflammation, pneumonia, severe acute respiratory syndrome, muscular sprain, stomach ulcer etc. Oxidative stress and inflammation were found to be linked with most of the diseases in recent times. Many ancient texts from Chinese Traditional Medicine, Ayurveda and Siddha, and Japanese Traditional medicine have documented the efficacy of H. cordata against oxidative stress and inflammation.

AIM OF THE STUDY

This review aims to provide up-to-date and comprehensive information on the efficacy of H. cordata extracts as well as its bioactive compounds both in vitro and in vivo, against oxidative stress and inflammation MATERIALS AND METHODS: Relevant information on H. cordata against oxidative stress and inflammation were collected from the established scientific databases such as NCBI, Web of Science, ScienceDirect, Elsevier, and Springer. Additionally, a few books and magazines were also consulted to get the important information.

RESULTS

Herbal medicines or plant products were traditionally being used for treating the oxidative stress and inflammation related diseases in diverse communities across the world. Scientifically, H. cordata has shown to target several signaling pathways and found to effectively reduce the oxidative stress and inflammation. Phyto-constituents such as afzelin, hyperoside and quercitrin have shown to reduce inflammation both in vitro and in vivo models. These molecules were also shown to have strong antioxidant properties both in vivo and in vitro models.

CONCLUSIONS

H. cordata extracts and its bioactive molecules were shown to have both anti-inflammatory and anti-oxidative properties. As both in vitro and in vivo studies were shown that H. cordata did not have any toxicity on the various model systems used, future clinical studies will hopefully make an impact on the future direction of treating inflammation-related diseases.

Resolvin D1 attenuates liver ischaemia/reperfusion injury through modulating thioredoxin 2-mediated mitochondrial quality control

BACKGROUND AND PURPOSE

Liver ischaemia and reperfusion (IR) injury is a sterile inflammatory response involving production of ROS. Mitochondrial homeostasis is maintained by mitochondrial quality control (QC). Thioredoxin (TRX) 2 is a key mitochondrial redox-sensitive protein. Resolvin D1 (RvD1), a specialized pro-resolving lipid mediator, exerts anti-inflammatory and antioxidant activities. We investigated mechanisms of RvD1 protection against IR-induced oxidative damage to the liver, focusing on TRX2-mediated mitochondrial QC.

EXPERIMENTAL APPROACH

Mice underwent partial warm IR. RvD1 was administered 1 h before ischaemia and immediately prior to reperfusion. Human liver carcinoma HepG2 cells were exposed to hypoxia/reoxygenation and transfected with TRX2 siRNA. Immunohistochemistry, Western blotting and enzyme assays were used to follow changes in mitochondrial structure and function.

KEY RESULTS

RvD1 attenuated hepatocellular damage following IR, assessed by serum aminotransferase activities and histology. RvD1 reduced mitochondrial swelling, lipid peroxidation and glutamate dehydrogenase release. Impaired activities of mitochondrial complexes I and III were restored by RvD1. RvD1 enhanced expression of the mitophagy-related protein, Parkin and inhibited accumulation of PTEN-induced putative kinase 1. RvD1 restored levels of mitochondrial biogenesis proteins including PPARγ coactivator 1α, nuclear respiratory factor 1 and mitochondrial transcription factor A and mtDNA level. RvD1 attenuated the increase in levels of the mitochondrial fission-related protein, dynamin-related protein 1. IR reduced TRX2 levels while increasing TRX2 association with TRX-interacting protein. RvD1 attenuated these changes. The regulatory effects of RvD1 on mitochondrial QC were abolished by TRX2 knockdown.

CONCLUSIONS AND IMPLICATIONS

We suggest that RvD1 ameliorated IR-induced hepatocellular damage by regulating TRX2-mediated mitochondrial QC.

Afzelin ameliorates D-galactosamine and lipopolysaccharide-induced fulminant hepatic failure by modulating mitochondrial quality control and dynamics

BACKGROUND AND PURPOSE

Fulminant hepatic failure (FHF) is a fatal clinical syndrome that results in excessive inflammation and hepatocyte death. Mitochondrial dysfunction is considered to be a possible mechanism of FHF. Afzelin, a flavonol glycoside found in Houttuynia cordata Thunberg, has anti-inflammatory and antioxidant properties. The present study elucidated the cytoprotective mechanisms of afzelin against D-galactosamine (GalN)/LPS induced FHF, particularly focusing on mitochondrial quality control and dynamics.

EXPERIMENTAL APPROACH

Mice were administered afzelin i.p. 1 h before receiving GalN (800 mg·kg^-1 )/LPS (40 μg·kg^-1 ), and they were then killed 5 h after GalN/LPS treatment.

KEY RESULTS

Afzelin improved the survival rate and reduced the serum levels of alanine aminotransferase and pro-inflammatory cytokines in GalN/LPS-treated mice. Afzelin attenuated the mitochondrial damage, as indicated by diminished mitochondrial swelling and mitochondrial glutamate dehydrogenase activity in GalN/LPS-treated mice. Afzelin enhanced mitochondrial biogenesis, as indicated by increased levels of PPAR-γ coactivator 1α, nuclear respiratory factor 1 and mitochondrial transcription factor A. Afzelin also decreased the level of mitophagy-related proteins, parkin and PTEN-induced putative kinase 1. Furthermore, while GalN/LPS significantly increased the level of fission-related protein, dynamin-related protein 1, and decreased the level of fusion-related protein, mitofusin 2; these effects were attenuated by afzelin.

CONCLUSIONS AND IMPLICATIONS

Our findings demonstrated that afzelin protects against GalN/LPS-induced liver injury by enhancing mitochondrial biogenesis, suppressing excessive mitophagy and balancing mitochondrial dynamics.