Alpha Mangostin Inhibits the Proliferation and Activation of Acetaldehyde Induced Hepatic Stellate Cells through TGF-β and ERK 1/2 Pathways

α-Mangostin Inhibits the Activation of Myofibroblasts via Downregulation of Linc-ROR-Mediated TGFB1/Smad Signaling

Oral submucous fibrosis (OSF) is a premalignant disorder and persistent activation of myofibroblasts is implicated in this pathological progression. Increasing attention has been addressed towards non-coding RNA-regulated myofibroblasts activities and the effects of phytochemicals on non-coding RNA modulation are of great importance. In the present study, we examined the anti-fibrosis property of α-mangostin, a xanthone isolated from the pericarp of mangosteen. We found that α-mangostin exhibited inhibitory potency in myofibroblast activities and expression of fibrosis markers at the concentrations that caused neglectable damage to normal cells. Apart from the downregulation of TGF-β1/Smad2 signaling, we found that α-mangostin attenuated the expression of long non-coding RNA LincROR as well. Our results demonstrated that the effects of α-mangostin on myofibroblast activation were reverted when LincROR was overexpressed. Additionally, we showed the expression of LincROR in OSF specimens was elevated and silencing of LincROR successfully attenuated myofibroblast characteristics and TGF-β1/Smad2 activation. Taken together, these findings indicated that the anti-fibrosis effects of α-mangostin merit consideration and may be due to the attenuation of LincROR.

Insights into Manganese Superoxide Dismutase and Human Diseases

Redox equilibria and the modulation of redox signalling play crucial roles in physiological processes. Overproduction of reactive oxygen species (ROS) disrupts the body's antioxidant defence, compromising redox homeostasis and increasing oxidative stress, leading to the development of several diseases. Manganese superoxide dismutase (MnSOD) is a principal antioxidant enzyme that protects cells from oxidative damage by converting superoxide anion radicals to hydrogen peroxide and oxygen in mitochondria. Systematic studies have demonstrated that MnSOD plays an indispensable role in multiple diseases. This review focuses on preclinical evidence that describes the mechanisms of MnSOD in diseases accompanied with an imbalanced redox status, including fibrotic diseases, inflammation, diabetes, vascular diseases, neurodegenerative diseases, and cancer. The potential therapeutic effects of MnSOD activators and MnSOD mimetics are also discussed. Targeting this specific superoxide anion radical scavenger may be a clinically beneficial strategy, and understanding the therapeutic role of MnSOD may provide a positive insight into preventing and treating related diseases.

Alpha-Mangostin as a New Therapeutic Candidate for Concanavalin A-Induced Autoimmune Hepatitis: Impact on the SIRT1/Nrf2 and NF-κB Crosstalk

Alpha-mangostin (α-MN) is a xanthone obtained from Garcinia mangostana that has diverse anti-oxidative and anti-inflammatory potentials. However, its pharmacological activity against autoimmune hepatitis (AIH) has not been investigated before. Concanavalin A (Con A) was injected into mice to induce AIH and two doses of α-MN were tested for their protective effects against Con A-induced AIH. The results demonstrated the potent hepatoprotective activity of α-MN evidenced by a remarkable decrease of serum indices of the hepatic injury and amendment of the histological lesions. α-MN significantly attenuated the level and immuno-expression of myeloperoxidase (MPO) indicating a decrease in the neutrophil infiltration into the liver. Additionally, the recruitment of the CD4+ T cell was suppressed in the α-MN pre-treated animals. α-MN showed a potent ability to repress the Con A-induced oxidative stress evident by the reduced levels of malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), and protein carbonyl (PC), as well as the enhanced levels of antioxidants as the reduced glutathione (GSH), superoxide dismutase (SOD), and total antioxidant capacity (TAC). The ELISA, RT-PCR, and IHC analyses revealed that α-MN enhanced the sirtuin1/nuclear factor erythroid 2 related factor-2 (SIRT1/Nrf2) signaling and its downstream cascade genes concurrently with the inhibition of the nuclear factor kappa B (NF-κB) and the inflammatory cytokines (tumor necrosis factor-alpha and interleukine-6) signaling. Taken together, these results inferred that the hepatoprotective activity of α-MN could prevent Con A-induced AIH through the modulation of the SIRT1/Nrf2/NF-κB signaling. Hence, α-MN may be considered as a promising candidate for AIH therapy.

Schisantherin D from Schisandra chinensis (Turcz.) Baill. exhibits anti-liver fibrosis capacity via modulating ETBR involved signaling, an in vitro and in vivo study

Excess levels of chemical hepatotoxicants (alcohol, aflatoxin B1), oxidative drugs (acetaminophen) and some cytokines (ET-1, TGF-β1) can induce chronic or acute liver injury. After these, the severe hepatic disease, especially the liver fibrosis (LF) occurs without taking measures, which brings threat to human health. The dibenzocyclooctadiene lignans of S. chinensis (SCDLs) were found to act as the hepatoprotective components via blocking endothelin B receptor (ETBR). While study on its anti-LF mechanisms especially for its refined compound of schisantherin D (SC-D) is still a lack. So this study aims to investigate the anti-fibrosis effect of SC-D with in vitro and in vivo assays. Bioinformatics analysis revealed the close relations of ETBR to Smad2, Smad3, Nrf2, etc. in LF-related signaling pathways (such as TGF-β/Smad and Nrf2/ARE). Histopathological staining on livers showed the recovery trend in SC-D treated LF mice. SC-D also modulated expressions of ETBR and fibrosis or anti-oxidative related proteins (such as TIMP1, p-Smad2/3, Nrf2, Smad7, etc.) in LF mice livers. Serum levels of TNF-α, COLI, ALT, AST and LDH in SC-D treated mice were also downregulated compared with LF mice, and upregulated expression of GSH. In vitro studies, SC-D also modulated expressions of LF-related proteins to the normal tendency in LX-2 cell, while weakened its anti- LX-2 proliferation effect by transfections of si-Smad7 or si-Nrf2. Accordingly the anti-LF approach of SC-D showed relations with modulating ETBR linked fibrosis and anti-oxidative related signaling. Also, Smad7 and Nrf2 might be the key factors for SC-D mediated anti-LF effect.

The metabolic and molecular mechanisms of α‑mangostin in cardiometabolic disorders (Review)

α-mangostin is a xanthone predominantly encountered in Garcinia mangostana. Extensive research has been carried out concerning the effects of this compound on various diseases, including obesity, cancer and metabolic disorders. The present review suggests that α-mangostin exerts promising anti-obesity, hepatoprotective, antidiabetic, cardioprotective, antioxidant and anti-inflammatory effects on various pathways in cardiometabolic diseases. The anti-obesity effects of α-mangostin include the reduction of body weight and adipose tissue size, the increase in fatty acid oxidation, the activation of hepatic AMP-activated protein kinase and Sirtuin-1, and the reduction of peroxisome proliferator-activated receptor γ expression. Hepatoprotective effects have been revealed, due to reduced fibrosis through transforming growth factor-β 1 pathways, reduced apoptosis and steatosis through reduced sterol regulatory-element binding proteins expression. The antidiabetic effects include decreased fasting blood glucose levels, improved insulin sensitivity and the increased expression of GLUT transporters in various tissues. Cardioprotection is exhibited through the restoration of cardiac functions and structure, improved mitochondrial functions, the promotion of M2 macrophage populations, reduced endothelial and cardiomyocyte apoptosis and fibrosis, and reduced acid sphingomyelinase activity and ceramide depositions. The antioxidant effects of α-mangostin are mainly related to the modulation of antioxidant enzymes, the reduction of oxidative stress markers, the reduction of oxidative damage through a reduction in Sirtuin 3 expression mediated by phosphoinositide 3-kinase/protein kinase B/peroxisome proliferator-activated receptor-γ coactivator-1α signaling pathways, and to the increase in Nuclear factor-erythroid factor 2-related factor 2 and heme oxygenase-1 expression levels. The anti-inflammatory effects of α-mangostin include its modulation of nuclear factor-κB related pathways, the suppression of mitogen-activated protein kinase activation, increased macrophage polarization to M2, reduced inflammasome occurrence, increased Sirtuin 1 and 3 expression, the reduced expression of inducible nitric oxide synthase, the production of nitric oxide and prostaglandin E2, the reduced expression of Toll-like receptors and reduced proinflammatory cytokine levels. These effects demonstrate that α-mangostin may possess the properties required for a suitable candidate compound for the management of cardiometabolic diseases.

A review of pathobiological mechanisms and potential application of medicinal plants for vascular aging: focus on endothelial cell senescence

Endothelial cell (EC) senescence plays a pivotal role in aging and is essential for the pathomechanism of aging-related diseases. Drugs targeting cellular senescence, such as senolytic or senomorphic drugs, may prevent aging and age-related diseases, but these bullets remain undeveloped to target EC senescence. Some medicinal plants may have an anti-senescence property but remain undiscovered. Deep learning has become an emerging approach for drug discovery by simply analyzing cellular morphology-based deep learning. This precious tool would be useful for screening the herb candidate in senescent EC rejuvenescence. Of note, several medicinal plants that can be found in Indonesia such as Curcuma longa L., Piper retrofractum, Guazuma ulmifolia Lam, Centella asiatica (L.) Urb., and Garcinia mangostana L. might potentially possess an anti-senescence effect. This review highlighted the importance of targeting EC senescence, the use of deep learning for medicinal plant screening, and some potential anti-senescence plants originating from Indonesia.

Guizhi Fuling pill attenuates liver fibrosis in vitro and in vivo via inhibiting TGF-β1/Smad2/3 and activating IFN-γ/Smad7 signaling pathways

Liver fibrosis resulting from chronic liver injuries (CLI) is a common health problem globally. Guizhi Fuling pill (GZFL), a modern preparation from traditional Chinese medicine, exhibited anti-dysmenorrhea, anti-inflammatory, and immune-regulative effects. However, the effect of GZFL on liver fibrosis remains unknown. In this research, LX-2 cells were stimulated with acetaldehyde for mimicking liver fibrosis progression in vitro. In addition, carbon tetrachloride (CCl₄)-induced mouse model of liver fibrosis was established as well. The data revealed GZFL obviously suppressed the proliferation and triggered the apoptosis of acetaldehyde-stimulated LX-2 cells. In addition, GZFL prevented acetaldehyde-induced activation of LX-2 cells via downregulation of TGF-β1, p-Smad2, p-Smad3, CUGBP1, and upregulation of p-STAT1 and Smad7. Meanwhile, GZFL significantly alleviated CCl₄‑induced liver fibrosis, as evidenced by the decrease of ALT and AST levels. Moreover, GZFL downregulated the expressions of TGF-β1, p-Smad2, p-Smad3, and CUGBP1 in CCl₄-treated mice. Furthermore, GZFL remarkably elevated the levels of IFN-γ, p-STAT1, and Smad7 in CCl₄-treated mice. To sum up, GZFL was able to inhibit liver fibrosis in vitro and in vivo through suppressing TGF-β1/Smad2/3-CUGBP1 signaling and activating IFN-γ/STAT1/Smad7 signaling. Thus, GZFL might have a potential to act as a therapeutic agent for anti-fibrotic therapy.

The Effect of Alpha Mangostin on Epithelial-Mesenchymal Transition on Human Hepatocellular Carcinoma HepG2 Cells Surviving Sorafenib via TGF-β/Smad Pathways

Purpose: This study was intended to find out the impact of alpha mangostin administration on the epithelial-mesenchymal transition (EMT) markers and TGF-β/Smad pathways in hepatocellular carcinoma Hep-G2 cells surviving sorafenib.

Methods: Hepatocellular carcinoma HepG2 cells were treated with sorafenib 10 μM. Cells surviving sorafenib treatment (HepG2^surv) were then treated vehicle, sorafenib, alpha mangostin, or combination of sorafenib and alpha mangostin. Afterward, cells were observed for their morphology with an inverted microscope and counted for cell viability. The concentrations of transforming growth factor (TGF)-β1 in a culture medium were examined using ELISA. The mRNA expressions of TGF-β1, TGF-β1-receptor, Smad3, Smad7, E-cadherin, and vimentin were evaluated using quantitative reverse transcriptase–polymerase chain reaction. The protein level of E-cadherin was also determined using western blot analysis.

Results: Treatment of alpha mangostin and sorafenib caused a significant decrease in the viability of sorafenib-surviving HepG2 cells versus control (both groups with P <0.05). Our study found that alpha mangostin treatment increased the expressions of vimentin (P <0.001 versus control). In contrast, alpha mangostin treatment tends to decrease the expressions of Smad7 and E-cadherin (both with P >0.05). In line with our findings, the expressions of TGF-β1 and Smad3 are significantly upregulated after alpha mangostin administration (both with P <0.05) versus control.

Conclusion: Alpha mangostin reduced cell viability of sorafenib-surviving HepG2 cells; however, it also enhanced epithelial–mesenchymal transition markers by activating TGF-β/Smad pathways.

A comprehensive review of natural products to fight liver fibrosis: Alkaloids, terpenoids, glycosides, coumarins and other compounds

The discovery of drugs to treat liver fibrosis has long been a challenge over the past decades due to its complicated pathogenesis. As a primary approach for drug development, natural products account for 30% of clinical drugs used for disease treatment. Therefore, natural products are increasingly important for their medicinal value in liver fibrosis therapy. In this part of the review, special focus is placed on the effect and mechanism of natural compounds, including alkaloids, terpenoids, glycosides, coumarins and others. A total of 36 kinds of natural compounds demonstrate significant antifibrotic effects in various liver fibrosis models in vivo and in hepatic stellate cells (HSCs) in vitro. Revealing the mechanism will provide further basis for clinical conversion, as well as accelerate drug discovery. The mechanism was further summarized with the finding of network regulation by several natural products, such as oxymatrine, paeoniflorin, ginsenoside Rg1 and taurine. Moreover, there are still improvements needed in investigating clinical efficacy, determining mechanisms, and combining applications, as well as semisynthesis and modification. Therefore, natural products area promising resource for agents that protect against liver fibrosis.

Puerarin alleviates liver fibrosis via inhibition of the ERK1/2 signaling pathway in thioacetamide-induced hepatic fibrosis in rats

Liver fibrosis is a complex pathological process and an early step in the progression of liver cirrhosis, which can eventually develop into hepatocellular carcinoma. Currently, there is no effective treatment for liver fibrosis. Puerarin is a traditional Chinese herb, which is commonly used in the treatment of various diseases. In addition, it is also believed to have a therapeutic effect in liver fibrosis. However, whether puerarin reduces liver fibrosis via the ERK1/2 signaling pathway to inhibit the activation of hepatic stellate cell (HSC) and excessive collagen deposition in liver fibrosis remains unknown. The aim of the current study was to establish a liver fibrosis in vivo model by intraperitoneal injection of thioacetamide (TAA) and investigate the effect of puerarin in the treatment of liver fibrosis. Hematoxylin and eosin and Van Gieson's staining were used to examine histopathological changes associated with liver fibrosis. Liver hydroxyproline content was examined to determine the total amount of collagen in the liver. The relative protein expression levels of transforming growth factor β1 (TGFβ1), α-smooth muscle actin (α-SMA), collagen type I, fibronectin, ERK1/2 and p-ERK1/2 were determined by western blot analysis. In the TAA group, histopathological changes and collagen fiber content in rat liver tissue samples were significantly increased compared with the control group (P<0.05). In addition, treatment with puerarin significantly decreased histopathological changes and collagen fiber content in rat liver tissue samples (P<0.05). The relative protein expression levels of TGFβ1, α-SMA, collagen type I, fibronectin and p-ERK1/2 were significantly upregulated in the TAA group compared with the control group (P<0.05), whereas puerarin treatment reversed these changes. These findings suggest that treatment with puerarin may reduce HSC activation and alleviate extracellular matrix protein expression levels by inhibiting the TGF-β/ERK1/2 pathway in liver fibrosis.