Purpurin ameliorates alcohol-induced hepatotoxicity by reducing ROS generation and promoting Nrf2 expression

Chronic alcohol intake disrupts cytochrome P450 enzyme activity in alcoholic fatty liver disease: insights into metabolic alterations and therapeutic targets

Introduction

Alcoholic fatty liver disease (AFLD) is a common consequence of chronic alcohol consumption, characterized by lipid accumulation and oxidative stress in the liver. Cytochrome P450 (CYP450) enzymes play essential roles in metabolizing alcohol and other compounds. However, the specific long-term effects of alcohol on these enzymes remain unclear.

Methods

This study the examines influence of prolonged ethanol exposure on CYP450 activity and expression in AFLD using a rat model. Key enzymes such as CYP2E1, CYP2D6, and CYP3A1 were assessed in relation to lipid accumulation and oxidative stress.

Results

Significant alterations were identified in the expression and activity of CYP2E1, CYP2D6, and CYP3A1, which were associated with increased lipid accumulation and oxidative stress in the liver. Additionally, the expression of P-glycoprotein (P-gp) was elevated, suggesting that chronic alcohol intake may impact drug transport and excretion.

Discussion

These findings provide new insights into the molecular mechanisms of AFLD and highlight the potential of CYP450 modulation as a therapeutic target. By elucidating how long-term ethanol exposure disrupts hepatic CYP450 enzyme profiles, this research lays the groundwork for developing personalized therapeutic strategies to improve outcomes for patients with AFLD.

Oxidative stress modulation in alcohol-related liver disease: From chinese botanical drugs to exercise-based interventions

Alcohol-related liver disease (ALD) is a chronic liver injury caused by long-term excessive alcohol consumption, with complex and multifaceted pathological mechanisms. Research indicates that oxidative stress (OS), inflammatory responses, and lipid metabolic disturbances induced by alcohol and its metabolites are primary contributors to hepatocyte injury, positioning OS as a key target in ALD treatment. The main non-pharmacological treatment for ALD is alcohol abstinence, while medical treatment primarily relies on Western pharmacological interventions. However, recent research has increasingly highlighted the potential of Chinese botanical drugs in improving histological features and modulating signaling pathways associated with OS in ALD, underscoring the therapeutic potential of traditional Chinese herb medicine. Despite these promising findings, the precise mechanisms and effects of these extracts remain incompletely understood, and potential side effects must be considered. Therefore, a comprehensive analysis of herbal extracts with therapeutic effects is essential to optimize clinical administration and ensure safe, effective treatment. This review focuses on OS as a central theme, categorizing Chinese botanical drugs into six major groups-flavonoids, polyphenols, terpenoids, alkaloids, saponins, and anthraquinones-all widely used in traditional Chinese herb medicine. The review provides an overview of their botanical characteristics and therapeutic actions in the context of ALD, offering insights into OS regulation and exploring their potential as treatments for ALD. Notably, physical exercise shares overlapping mechanisms with botanical drugs in regulating OS. Combining two strategies could offer a promising integrative treatment for ALD, though further research is needed to confirm their synergistic benefits and optimize clinical applications.

Proanthocyanidins alleviate acute alcohol liver injury by inhibiting pyroptosis via inhibiting the ROS-MLKL-CTSB-NLRP3 pathway

BACKGROUND

Alcoholic Liver Disease (ALD) is a hepatic disorder resulting from prolonged or excessive alcohol intake. The predominant manifestation of ALD is fatty liver, which progresses to alcoholic hepatitis as the disease worsens. Pyroptosis is a novel type of programmed cell death that is intricately linked to the inflammatory cascade, presenting a promising avenue for therapeutic intervention in the management of ALD. Oligomeric proanthocyanidins (OPCs) are polyphenols extracted from grape seeds that have anti-inflammatory and antioxidant properties. However, whether OPCs can treat ALD by suppressing pyroptosis is not completely clarified.

PURPOSE

To explore the role of OPCs in ALD to inhibit pyroptosis and its mechanism.

METHODS

In vitro, HepG2 cells were employed to evaluate the beneficial impact of OPCs on alcohol-induced pyroptosis. MTT colorimetric method, enzyme-linked immunosorbent assay (ELISA), western blot (WB), immunofluorescence, acridine orange (AO) staining, and reactive oxygen species (ROS) assay were performed. In vivo, C57BL mice were used and gavaged with alcohol and OPCs. Hematoxylin-eosin staining (HE) staining, alanine aminotransferase (ALT), aspartate aminotransferase (AST) level assay, and WB were performed.

RESULTS

The findings revealed that OPCs could reduce the alcohol-induced increase in pyroptosis-related proteins, such as pyrin domain-containing 3 protein (NLRP3), cleaved-caspase 1, gasdermin D (GSDMD-N), Interleukin-18 (IL-18), IL-1β (IL-1β). In in vitro mechanistic experiments, We discovered that OPCs ameliorate alcohol-induced pyroptosis by decreasing cathepsin B (CTSB) leakage-mediated NLRP3 activation. More significantly, we discovered that alcohol phosphorylates mixed lineage kinase domain-like protein (MLKL), enabling P-MLKL to translocate to the lysosomal membrane and induce lysosomal membrane permeabilization (LMP). OPCs might counteract the effects of alcohol by reducing the leakage of CTSB and inhibiting the phosphorylation of MLKL through the scavenging of ROS.

CONCLUSIONS

These results suggested that OPCs might counteract ALD by inhibiting pyroptosis through the ROS-MLKL-CTSB-NLRP3 pathway. Our study offered fresh insight into the ways in which naturally occurring chemicals shield ALD against harm.

Phellinus linteus (Agaricomycetes) Polysaccharides Ameliorate Inflammatory Injury in H2O2-Induced Caco-2 Cells and DSS-Induced Ulcerative Colitis Mice

Phellinus linteus (Agaricomycetes) is a valuable medicinal mushroom traditionally used as a food supplement and medicinal ingredient. Polysaccharides of Ph. linteus (PLP) possess strong anti-inflammatory effects and gut microbiota modulating properties. However, the mechanism of its efficacy in ulcerative colitis (UC) remains unclear. This study utilized 1mM H2O2 to induce an in vitro model of UC in Caco-2 cells. Additionally, a 3% solution of dextran sulfate sodium salt (DSS) was employed to establish an in vivo UC model in mice. After treating the cells with PLP at various concentrations, there was a significant reduction in the mRNA expression of TNF-α and IL-6, and the nuclear factor-κB (NF-κB) signaling pathway was also inhibited. Concurrently, symptoms such as colon shortening, weight loss, and a decrease in disease activity index (DAI) scores were significantly improved in UC mice. Additionally, the treatment led to downregulated expression of TNF-α and IFN-γ mRNA in colon tissues. PLP had shown potential in reducing inflammation and oxidative stress in Caco-2 cells, demonstrating therapeutic effects in treating UC-like inflammation by inhibiting the NF-κ signaling pathway and activating the nuclear factor erythroid derived 2-like 2(Nrf2)/heme oxygenase-1(HO-1) signaling pathway. These findings suggest that PLP has great potential for further investigation and development in UC treatment.

Purpurin ameliorated neuropathic allodynia and hyperalgesia by modulating neuronal mitochondrial bioenergetics and redox status in type 1 diabetic mice

A substantial proportion of diabetic patients suffer a debilitating and persistent pain state, known as peripheral painful neuropathy that necessitates improved therapy or antidote. Purpurin, a natural anthraquinone compound from Rubia tinctorum L., has been reported to possess antidepressant activity in preclinical studies. As antidepressants have been typically used as standard agents against persistent neuropathic pain, this study aimed to probe the effect of purpurin on neuropathic pain associated with streptozotocin-induced type 1 diabetes in male C57BL6J mice. The Hargreaves test and the von Frey test were used to assess the pain-like behaviors, shown as heat hyperalgesia and mechanical allodynia respectively. Chronic treatment of diabetic mice with purpurin not only ameliorated the established symptoms of heat hyperalgesia and mechanical allodynia, but also arrested the development of these pain states given preemptively at low doses. Although purpurin treatment hardly impacted on metabolic disturbance in diabetic mice, it ameliorated exacerbated oxidative stress in pain-associated tissues, improved mitochondrial bioenergetics in dorsal root ganglion neurons and restored nerve conduction velocity in sciatic nerves. Notably, the analgesic actions of purpurin were modified by pharmacologically manipulating redox status and mitochondrial bioenergetics. These findings unveil the analgesic activity of purpurin, an effect that is causally associated with its bioenergetics-enhancing and antioxidant effects, in mice with type 1 diabetes.

A Review on Bioactive Anthraquinone and Derivatives as the Regulators for ROS

Anthraquinones are bioactive natural products, which are often found in medicinal herbs. These compounds exert antioxidant-related pharmacological actions including neuroprotective effects, anti-inflammation, anticancer, hepatoprotective effects and anti-aging, etc. Considering the benefits from their pharmacological use, recently, there was an upsurge in the development and utilization of anthraquinones as reactive oxygen species (ROS) regulators. In this review, a deep discussion was carried out on their antioxidant activities and the structure-activity relationships. The antioxidant mechanisms and the chemistry behind the antioxidant activities of both natural and synthesized compounds were furtherly explored and demonstrated. Due to the specific chemical activity of ROS, antioxidants are essential for human health. Therefore, the development of reagents that regulate the imbalance between ROS formation and elimination should be more extensive and rational, and the exploration of antioxidant mechanisms of anthraquinones may provide new therapeutic tools and ideas for various diseases mediated by ROS.

Escin enhanced the efficacy of sorafenib by autophagy-mediated apoptosis in lung cancer cells

Combining anti-cancer drugs has been exploited as promising treatment strategy to target lung cancer. Synergistic chemotherapies increase anti-cancer effect and reduce effective drug doses and side effects. In this study, therapeutic potential of escin in combination with sorafenib has been explored. 3-(4,5-Dimethylthiazol-2-yl)-2 5-diphenyltetrazolium bromide assay was used to calculate IC50 values. The synergy was evaluated using Chou-Talaly algorithm. Cellular reactive oxygen species, mitochondrial membrane potential, annexin V, and cell-cycle studies were done by flow-cytometer, and autophagy biomarkers expression were determined using western blotting. Moreover, autophagy was knocked down using ATG5 siRNA to confirm its role, diethylnitrosamine-induced lung cancer model was used to check the synergy of sorafenib/escin. Escin significantly reduced the IC50 of sorafenib in A549 and NCIH460 cells. The combination of sorafenib/escin produced a 2.95 and 5.45 dose reduction index for sorafenib in A549 and NCI-H460 cells. The combination of over-expressed p62 and LC3-II reflects autophagy block-mediated late apoptosis. This phenomenon was reconfirmed by ATG5 knockdown. This combination also selectively targeted G0/G1 phase of cancer cells. In in vivo study, the combination reduced tumour load and lower elevated serum biochemical parameters. The combination of sorafenib/escin synergistically inhibits autophagy to induce late apoptosis in lung cancer cells' G0/G1 phase.

On the Role of ROS and Glutathione in the Mode of Action Underlying Nrf2 Activation by the Hydroxyanthraquinone Purpurin

Purpurin is a major anthraquinone present in the roots of Rubia cordifolia (madder). Purpurin is known to activate Nrf2 (Nuclear transcription factor erythroid 2-related factor 2) EpRE (electrophile responsive element) mediated gene expression as a potential beneficial effect. This study aimed to elucidate the balance between the electrophilicity or pro-oxidant activity of purpurin underlying the Nrf2 induction. For this, Nrf2 activation with modified intracellular glutathione (GSH) levels was measured in an Nrf2 CALUX reporter gene assay. In addition, both cell-free and intracellular ROS formation of purpurin with modified (intracellular) GSH levels at different pH were quantified using the DCF-DA assay. GSH adduct formation was evaluated by UPLC and LC-TOF-MS analysis. GSH and GSSG levels following purpurin incubations were quantified by LC-MS/MS. We show that Nrf2 induction by purpurin was significantly increased in cells with buthionine sulfoximine depleted GSH levels, while Nrf2 induction was decreased upon incubation of the cells with N-acetylcysteine being a precursor of GSH. In cell-free incubations, ROS formation increased with increasing pH pointing at a role for the deprotonated form of purpurin. Upon incubations of purpurin with GSH at physiological pH, GSH adduct formation appeared negligible (<1.5% of the added purpurin). The addition of GSH resulted in conversion of GSH to GSSG and significantly reduced the ROS formation. Together these results demonstrate that Nrf2 induction by purpurin originates from intracellular ROS formation and not from its electrophilicity, which becomes especially relevant when intracellular GSH levels can no longer scavenge the ROS. The present study demonstrated that the efficiency of intracellular Nrf2 activation by purpurin and related anthraquinones will depend on (i) their pKa and level of deprotonation at the intracellular pH, (ii) the oxidation potential of their deprotonated form and (iii) the intracellular GSH levels. Thus, the Nrf2 induction by purpurin depends on its pro-oxidant activity and not on its electrophilicity.

Induction of Nrf2-EpRE-mediated gene expression by hydroxyanthraquinones present in extracts from traditional Chinese medicine and herbs

Hydroxyanthraquinones that can be present in traditional Chinese medicine (TCM) and herbal extracts have claimed beneficial intestinal effects. We examined the ability of a panel hydroxyanthraquinones, and methanolic extracts from selected TCM and herbal granules to activate Nrf2-EpRE mediated gene expression using a reporter-gene assay. The results indicate that purpurin, aloe-emodin, 2-hydroxy-3-methylanthraquinone and rhein induced Nrf2 mediated gene expressions with a high induction factor (IFs>10), with BMCL₁₀ values (the lower confidence limit of the concentration giving 10% added response above background) of 16 μM, 1.1 μM, 23 μM and 2.3 μM, respectively, while aurantio-obtusin, obtusifolin, rubiadin 1-methyl ether and emodin were less potent (IFs<5), with BMCL₁₀ values for added response above background level of 4.6 μM, 15 μM, 9.8 μM and 3.8 μM, respectively. All TCM extracts and the herbal extracts of Aloe Vera, Polygonum multiflorum, Rubia (cordifolia) and Rheum officinale activated the Nrf2-EpRE pathway. Of the TCM extracts, Chuan-Xin-Lian-Kang-Yan-Pian was the most potent Nrf2-inducer. LC-MS/MS analysis indicated the presence of selected hydroxyanthraquinones in the extracts and herbs, in part explaining their Nrf2-EpRE mediated activity. In conclusion, different hydroxyanthraquinones have different potencies of Nrf2 activation. The Nrf2 activation by extracts from TCM and herbs can be partially explained by the presence of selected hydroxyanthraquinones.