Calcium channel blockers ameliorate iron overload-associated hepatic fibrosis by altering iron transport and stellate cell apoptosis

Nimodipine ameliorates liver fibrosis via reshaping liver immune microenvironment in TAA-induced in mice

Nimodipine, a calcium antagonist, exert beneficial neurovascular protective effects in clinic. Recently, Calcium channel blockers (CCBs) was reported to protect against liver fibrosis in mice, while the exact effects of Nimodipine on liver injury and hepatic fibrosis remain unclear. In this study, we assessed the effect of nimodipine in Thioacetamide (TAA)-induced liver fibrosis mouse model. Then, the collagen deposition and liver inflammation were assessed by HE straining. Also, the frequency and phenotype of NK cells, CD4+T and CD8+T cells and MDSC in liver and spleen were analyzed using flow cytometry. Furthermore, activation and apoptosis of primary Hepatic stellate cells (HSCs) and HSC line LX2 were detected using α-SMA staining and TUNEL assay, respectively. We found that nimodipine administration significantly attenuated liver inflammation and fibrosis. And the increase of the numbers of hepatic NK and NKT cells, a reversed CD4+/CD8+T ratio, and reduced the numbers of MDSC were observed after nimodipine treatment. Furthermore, nimodipine administration significantly decreased α-SMA expression in liver tissues, and increased TUNEL staining adjacent to hepatic stellate cells. Nimodipine also reduced the proliferation of LX2, and significantly promoted high level of apoptosis in vitro. Moreover, nimodipine downregulated Bcl-2 and Bcl-xl, simultaneously increased expression of JNK, p-JNK, and Caspase-3. Together, nimodipine mediated suppression of growth and fibrogenesis of HSCs may warrant its potential use in the treatment of liver fibrosis.

Iron as a therapeutic target in chronic liver disease

It was clearly realized more than 50 years ago that iron deposition in the liver may be a critical factor in the development and progression of liver disease. The recent clarification of ferroptosis as a specific form of regulated hepatocyte death different from apoptosis and the description of ferritinophagy as a specific variation of autophagy prompted detailed investigations on the association of iron and the liver. In this review, we will present a brief discussion of iron absorption and handling by the liver with emphasis on the role of liver macrophages and the significance of the iron regulators hepcidin, transferrin, and ferritin in iron homeostasis. The regulation of ferroptosis by endogenous and exogenous mod-ulators will be examined. Furthermore, the involvement of iron and ferroptosis in various liver diseases including alcoholic and non-alcoholic liver disease, chronic hepatitis B and C, liver fibrosis, and hepatocellular carcinoma (HCC) will be analyzed. Finally, experimental and clinical results following interventions to reduce iron deposition and the promising manipulation of ferroptosis will be presented. Most liver diseases will be benefited by ferroptosis inhibition using exogenous inhibitors with the notable exception of HCC, where induction of ferroptosis is the desired effect. Current evidence mostly stems from in vitro and in vivo experimental studies and the need for well-designed future clinical trials is warranted.

Iron-Induced Hepatocarcinogenesis—Preventive Effects of Nutrients

The liver is a primary organ that stores body iron, and plays a central role in the regulation of iron homeostasis. Hepatic iron overload (HIO) is a prevalent feature among patients with chronic liver diseases (CLDs), including alcoholic/nonalcoholic liver diseases and hepatitis C. HIO is suggested to promote the progression toward hepatocellular carcinoma because of the pro-oxidant nature of iron. Iron metabolism is tightly regulated by various factors, such as hepcidin and ferroportin, in healthy individuals to protect the liver from such deteriorative effects. However, their intrinsic expressions or functions are frequently compromised in patients with HIO. Thus, various nutrients have been reported to regulate hepatic iron metabolism and protect the liver from iron-induced damage. These nutrients are beneficial in HIO-associated CLD treatment and eventually prevent iron-mediated hepatocarcinogenesis. This mini-review aimed to discuss the mechanisms and hepatocarcinogenic risk of HIO in patients with CLDs. Moreover, nutrients that hold the potential to prevent iron-induced hepatocarcinogenesis are summarized.

Resveratrol ameliorates iron overload induced liver fibrosis in mice by regulating iron homeostasis

This study is intended to explore the protective effects of resveratrol (RES) on iron overload-induced liver fibrosis and its mechanism. Iron dextran (50 mg/kg) was injected intraperitoneally in all groups except the control group. Mice in the L-RES, M-RES and H-RES groups were gavaged with RES solution at 25, 50 mg/kg and 100 mg/kg, respectively, 4 h before injection of iron dextran every day; mice in the deferoxamine (DFO) group were injected with DFO intraperitoneally (100 mg/kg); mice in the control group received isovolumetric saline. After seven weeks of RES administration, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) activities and liver hydroxyproline (Hyp) levels were reduced; the malondialdehyde (MDA) activities decreased and the levels of superoxide dismutase (SOD) and glutathione (GSH) were raised. Hematoxylin and eosin (H&E), Prussian, and Masson staining indicated that RES treatment could improve cell damage and reduce hepatic iron deposition and collagen deposition in iron-overload mice. The expression of Bcl-2 was increased, the expression levels of Bax and caspase-3 were decreased under RES treatment. Moreover, RES reduced the expression of hepcidin, ferritin (Ft), divalent metal transporter-1 (DMT-1), transferrin receptor-2 (TFR-2), and raised the expression of ferroprotein-1 (FPN-1). In conclusion, RES could ameliorate iron overload-induced liver fibrosis, and the potential mechanisms may be related to antioxidant, anti-inflammatory, anti-apoptotic, and more importantly, regulation of iron homeostasis by reducing iron uptake and increasing iron export.

Baicalein Ameliorates Myocardial Ischemia Through Reduction of Oxidative Stress, Inflammation and Apoptosis via TLR4/MyD88/MAPKS/NF-κB Pathway and Regulation of Ca2+ Homeostasis by L-type Ca2+ Channels

Background: Baicalein (Bai) is the principal ingredient of Scutellaria baicalensis Georgi. Reports concerning the therapeutic advantages in treating cardiovascular diseases have been published. However, its protective mechanism towards myocardial ischemia (MI) is undefined.

Objective: The aim of this study was to investigate the protective mechanisms of Bai on mouse and rat models of MI.

Methods: Mice were pre-treated with Bai (30 and 60 mg/kg/day) for 7 days followed by subcutaneous injections of isoproterenol (ISO, 85 mg/kg/day) for 2 days to establish the MI model. Electrocardiograms were recorded and serum was used to detect creatine kinase (CK), lactate dehydrogenase (LDH), superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and malondialdehyde (MDA). Cardiac tissues were used to detect Ca²⁺ concentration, morphological pathologies, reactive oxygen species (ROS), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). In addition, the expression levels of Bcl-2-associated X (Bax), B cell lymphoma-2 (Bcl-2), Caspase-3, Toll-like receptor-4 (TLR4), myeloid differentiation protein 88 (MyD88), nuclear factor-kappa B (NF-κB), p-p38, p-extracellular signal-regulated kinase1/2 (p-ERK1/2) and c-Jun N-terminal kinase (p-JNK) were assessed by western blots in myocardial tissues. The effects of Bai on L-type Ca²⁺ currents (I_Ca-L), contractility and Ca²⁺ transients in rat isolated cardiomyocytes were monitored by using patch clamp technique and IonOptix system. Moreover, ISO-induced H9c2 myocardial injury was used to detect levels of inflammation and apoptosis.

Results: Bai caused an improvement in heart rate, ST-segment and heart coefficients. Moreover, Bai led to a reduction in CK, LDH and Ca²⁺ concentrations and improved morphological pathologies. Bai inhibited ROS generation and reinstated SOD, CAT and GSH activities in addition to inhibition of replenishing MDA content. Also, expressions of IL-6 and TNF-α in addition to Bax and Caspase-3 were suppressed, while Bcl-2 expression was upregulated. Bai inhibited protein expressions of TLR4/MyD88/MAPK_S/NF-κB and significantly inhibited I_Ca-L, myocyte contraction and Ca²⁺ transients. Furthermore, Bai caused a reduction in inflammation and apoptosis in H9c2 cells.

Conclusions: Bai demonstrated ameliorative actions towards MI, which might have been related to attenuation of oxidative stress, inflammation and apoptosis via suppression of TLR4/MyD88/MAPK_S/NF-κB pathway and adjustment of Ca²⁺ homeostasis via L-type Ca²⁺ channels.

Distribution and Associated Factors of Hepatic Iron-A Population-Based Imaging Study

Hepatic iron overload can cause severe organ damage; therefore, an early diagnosis and the identification of potential risk factors is crucial. We aimed to investigate the sex-specific distribution of hepatic iron content (HIC) in a population-based cohort and identify relevant associated factors from a panel of markers. We analyzed N = 353 participants from a cross-sectional sample (KORA FF4) who underwent whole-body magnetic resonance imaging. HIC was assessed by single-voxel spectroscopy with a high-speed T2-corrected multi-echo technique. A large panel of markers, including anthropometric, genetic, and laboratory values, as well as behavioral risk factors were assessed. Relevant factors associated with HIC were identified by variable selection based on LASSO regression with bootstrap resampling. HIC in the study sample (mean age at examination: 56.0 years, 58.4% men) was significantly lower in women (mean ± SD: 39.2 ± 4.1 s^-1) than in men (41.8 ± 4.7 s^-1, p < 0.001). Relevant factors associated with HIC were HbA1c as well as prediabetes for men and visceral adipose tissue as well as age for women. Hepatic fat, alcohol consumption, and genetic risk score for iron levels were associated with HIC in both sexes. In conclusion, there are sex-specific associations of HIC with markers of body composition, glucose metabolism, and alcohol consumption.

Calcium channels and iron metabolism: A redox catastrophe in Parkinson's disease and an innovative path to novel therapies?

Autonomously spiking dopaminergic neurons of the substantia nigra pars compacta (SNpc) are exquisitely specialized and suffer toxic iron-loading in Parkinson's disease (PD). However, the molecular mechanism involved remains unclear and critical to decipher for designing new PD therapeutics. The long-lasting (L-type) Ca_V1.3 voltage-gated calcium channel is expressed at high levels amongst nigral neurons of the SNpc, and due to its role in calcium and iron influx, could play a role in the pathogenesis of PD. Neuronal iron uptake via this route could be unregulated under the pathological setting of PD and potentiate cellular stress due to its redox activity. This Commentary will focus on the role of the Ca_V1.3 channels in calcium and iron uptake in the context of pharmacological targeting. Prospectively, the audacious use of artificial intelligence to design innovative Ca_V1.3 channel inhibitors could lead to breakthrough pharmaceuticals that attenuate calcium and iron entry to ameliorate PD pathology.

Calcium chelator BAPTA‑AM protects against iron overload‑induced chondrocyte mitochondrial dysfunction and cartilage degeneration

Osteoarthritis (OA) is a common joint disease that is characterized by cartilage degradation. Iron deposition in the joints is common during the pathogenic progression of OA and recent studies have indicated that iron overload is an important contributor to OA progression. Calcium chelators have been reported to inhibit iron influx via modulating transferrin receptor protein 1 internalization, and they have been identified as a potential approach to the treatment of iron overload‑induced diseases. The aim of the present study was to investigate the effect of calcium chelators on the progression of iron overload‑induced OA. Primary chondrocytes were treated with various concentrations of ferric ammonium citrate (FAC) to mimic iron overload in vitro, followed by co‑treatment with the calcium chelator BAPTA acetoxymethyl ester (BAPTA‑AM). Subsequently, intracellular iron levels, cell viability, reactive oxygen species (ROS) levels, mitochondrial function and morphological changes, as well as MMP levels, were detected using commercial kits. It was demonstrated that FAC treatment significantly promoted chondrocyte apoptosis and the expression of MMPs, and these effects were reversed by co‑treatment with BAPTA‑AM. Moreover, BAPTA‑AM suppressed iron influx into chondrocytes and inhibited iron overload‑induced ROS production and mitochondrial dysfunction. These results indicated that calcium chelators may be of value in the treatment of iron metabolism‑related diseases and iron overload‑induced OA progression.

Ferulic acid attenuates non-alcoholic steatohepatitis by reducing oxidative stress and inflammation through inhibition of the ROCK/NF-κB signaling pathways

Ferulic acid (FA) is a natural polyphenol compound existing in many plants. The purpose of this study was to investigate the effect of FA on non-alcoholic steatohepatitis (NASH) induced by high-cholesterol and high-fat diet (HCHF) and its possible mechanism. Rats were fed HCHF for 12 weeks to establish NASH model. FA improved liver coefficients and had no effect on body weight changes. FA could reduce serum alanine transferase (ALT) and aspartate transferase (AST) activities. FA attenuated the increase of total cholesterol (TC), triglyceride (TG) and low-density lipoprotein (LDL) levels caused by NASH, improved the liver pathological damage induced by NASH, and inhibited the progression of liver fibrosis. FA prevented the production of reactive oxygen species (ROS) and the increase of malondialdehyde (MDA) levels, and attenuated the decrease in superoxide dismutase (SOD) activity. Meanwhile, FA significantly restored the levels of interleukin (IL)-1β, IL-6 and tumor necrosis factor-α (TNF-α). In addition, we also found that FA inhibited the activity of ROCK and the activation of NF-κB signaling pathway in the liver of NASH rats. Overall, FA has a hepatoprotective anti-oxidative stress and anti-inflammatory effects in NASH rats, and its mechanism may be related to the inhibition of ROCK/NF-κB signaling pathway.

Ameliorative effects and mechanisms of salvianic acid A on retinal iron overload in vivo and in vitro

Excessive iron can be accumulated in the retina and lead to retinal iron overload. Salvianic acid A (SAA) has a variety of pharmacologic effects, but there is only a limited understanding of its benefits for retinal iron overload. The aim of this study was to examine the protective effects and latent mechanisms of SAA on retinal iron overload. SAA reduced iron in the serum and retina, attenuated pathophysiological changes, and reduced retinal iron deposition in the retinas of iron-overloaded mice. It also reduced intracellular iron in ARPE-19 cells by regulating iron-handling proteins and chelating with iron. It also significantly inhibited cellular oxidative and inflammatory damage by increasing the nuclear translocation of nuclear erythroid 2-related factor 2 (Nrf2) while decreasing nuclear factor-kappa B (NF-κB), protecting the ARPE-19 cells from apoptosis by suppressing the Bax/Bcl-2 ratio, cytochrome c release, caspase activation, and poly ADP-ribose polymerase cleavage. The ability of SAA to inhibit apoptosis, increase nuclear Nrf2 expression, and decrease nuclear NF-κB expression was further confirmed in the retinas of iron-overloaded mice. This study demonstrates that SAA shows significant protective effects against retinal iron overload; its mechanisms might be associated with iron chelation; regulation of iron-handling proteins; and inhibition of oxidative stress, inflammation and apoptosis.

Astragaloside IV protects against retinal iron overload toxicity through iron regulation and the inhibition of MAPKs and NF-κB activation

Iron overload toxicity has been implicated in retinal pigment epithelial cell injury in age-related macular degeneration. This study investigates the effects of astragaloside IV (AS-IV), a potential retinal protective agent, on the toxicity process of retinal iron overload in vivo and in vitro. AS-IV partially restored the retinal expression of rhodopsin and retinal pigment epithelium-specific 65 kDa protein, suppressed oxidative stress and inflammatory markers, and alleviated iron deposition and retinal pathological changes in vivo. Also, AS-IV inhibited the phosphorylation of p38 and ERK mitogen-activated protein kinases (MAPKs), as well as the nuclear translocation of nuclear factor-kappa B (NF-κB). Furthermore, AS-IV prevented cell death by decreasing the ratio of Bax/Bcl-2, caspase-3, and cleaved caspase-3 expression in vitro. Although there are no chelation effects between AS-IV and iron, AS-IV can reduce intracellular iron by regulating iron-handling proteins in ARPE-19 cells (Cav1.2, divalent metal transporter-1, transferrin receptor 1, and heavy-chain ferritin). In conclusion, the results show that AS-IV has significant protective effects against retinal iron overload toxicity and suggest that iron regulation and the inhibition of MAPKs and NF-κB activation might be mechanisms underlying the effects of AS-IV.

L-type calcium channel blockers decrease the iron overload-mediated oxidative stress in renal epithelial cells by reducing iron accumulation

Iron-mediated oxidative stress has been recognized as one of the leading causes of chronic kidney injury. The effect of L-type calcium channel (LTCC) blocker on iron overload has been shown in cardiomyocytes, liver cells, and nerve cells. So far, few studies have examined whether blockers improve kidney iron-mediated oxidative stress. Yet, the precise mechanism through which blockers regulate kidney iron transport still remains unclear. In the present work, treatment with nifedipine or verapamil decreased oxidative stress and reduced the cell apoptosis-induced by ferric ammonium citrate (P < 0.05), decreased cellular iron contents, and prevented the rising of iron level-induced by ferric ammonium citrate (P > 0.05) in HK-2 and HEK293 cells. Besides, nifedipine and verapamil treatments increased the expression of divalent metal transporter 1, divalent metal transporter ZIP14, and ferroportin1 in HK-2 cells and increased ferroportin1 expression in HEK293 cells. In summary, LTCC blockers alleviate iron overload-induced oxidative stress in renal epithelial cells by blocking the iron uptake and enhancing cellular iron transport and/or iron export, thus synergistically reducing the cellular iron accumulation. Consequently, LTCC blockers may be used as a novel treatment for the prevention of primary or secondary iron overload-kidney injury.

[6]-Gingerol Ameliorates ISO-Induced Myocardial Fibrosis by Reducing Oxidative Stress, Inflammation, and Apoptosis through Inhibition of TLR4/MAPKs/NF-κB Pathway

SCOPE

[6]-Gingerol is one of the primary pungent constituents of ginger. While [6]-gingerol has many pharmacological effects, its benefits for myocardial fibrosis, including its exact role and underlying mechanisms, remain largely unexplored. The present study is designed to characterize the cardio-protective effects of [6]-gingerol in myocardial fibrosis mice and possible underlying mechanisms.

METHODS AND RESULTS

Mice are subcutaneously injected with isoproterenol (ISO, 10 mg kg^-1 ) and gavaged with [6]-gingerol (10, 20 mg kg^-1 day^-1 ) for 14 days. Pathological alterations, fibrosis, oxidative stress, inflammation response, and apoptosis are examined. In ISO-induced myocardial fibrosis, [6]-gingerol treatment decreases the J-point, heart rate, cardiac weight index, left ventricle weight index, creatine kinase (CK), and lactate dehydrogenase serum levels, calcium concentration, reactive oxygen species, malondialdehyde, and glutathione disulfide (GSSG), and increases levels of superoxide dismutase, catalase, glutathione, and GSH/GSSG. Further, [6]-gingerol improved ISO-induced morphological pathologies, inhibited inflammation and apoptosis, and suppressed the toll-like receptor-4 (TLR4)/mitogen-activated protein kinases (MAPKs)/nuclear factor κB (NF-κB) signaling pathways.

CONCLUSION

The protective effect of [6]-gingerol in mice with ISO-induced myocardial fibrosis may be related to the inhibition of oxidative stress, inflammation, and apoptosis, potentially through the TLR4/MAPKs/NF-κB signaling pathway.

Puerarin protects against iron overload-induced retinal injury through regulation of iron-handling proteins

Excess iron content can build up in the retina and lead to iron-mediated retinal injury. An important isoflavone C-glucoside, puerarin, has been reported to be involved in retinal protection. In this experiment, we studied the effects and potential mechanisms of puerarin on retinal injury in vivo and in vitro. We found that puerarin reduced serum and retinal iron content, attenuated the pathophysiological changes and retinal iron deposition, and partially prevented the decrease of rhodopsin and retinal pigment epithelium-specific 65 kDa protein expression in retinas of iron-overload mice. Puerarin rescued the abnormal expression of iron-handling proteins in the mouse retina and suppressed the oxidative stress induced by iron overload, as evident from the enhanced activity of superoxide dismutase, catalase, and glutathione peroxidase and decreased content of malondialdehyde. Moreover, puerarin inhibited the phosphorylation of p38 and ERK mitogen-activated protein kinases (MAPKs) and signal transducer and activator of transcription 3 (STAT3), thereby protecting the retinal cells from apoptosis by suppressing cytochrome c release, caspase activation, and poly (ADP-ribose) polymerase cleavage in vivo. Also, the ability of puerarin to regulate iron-handling proteins, decrease intracellular Fe²⁺, and inhibit cell apoptosis was further confirmed in ARPE-19 cells. The experimental data verify the protective role of puerarin in the treatment of retinal injury caused by iron overload; its possible mechanisms might be associated with regulation of iron-handling proteins, enhancement of the antioxidant capacity, and the inhibition of MAPK and STAT3 activation and the apoptotic pathways under iron overload conditions.

SOD2 Mediates Curcumin-Induced Protection against Oxygen-Glucose Deprivation/Reoxygenation Injury in HT22 Cells

Curcumin (Cur) induces neuroprotection against brain ischemic injury; however, the mechanism is still obscure. The aim of this study is to explore the potential neuroprotective mechanism of curcumin against oxygen-glucose deprivation/reoxygenation (OGD/R) injury in HT22 cells and investigate whether type-2 superoxide dismutase (SOD2) is involved in the curcumin-induced protection. In the present study, HT22 neuronal cells were treated with 3 h OGD plus 24 h reoxygenation to mimic ischemia/reperfusion injury. Compared with the normal cultured control group, OGD/R treatment reduced cell viability and SOD2 expression, decreased mitochondrial membrane potential (MMP) and mitochondrial complex I activity, damaged cell morphology, and increased lactic dehydrogenase (LDH) release, cell apoptosis, intracellular reactive oxygen species (ROS), and mitochondrial superoxide (P < 0.05). Meanwhile, coadministration of 100 ng/ml curcumin reduced the cell injury and apoptosis, inhibited intracellular ROS and mitochondrial superoxide accumulation, and ameliorated intracellular SOD2, cell morphology, MMP, and mitochondrial complex I activity. Downregulating the SOD2 expression by using siRNA, however, significantly reversed the curcumin-induced cytoprotection (P < 0.05). These findings indicated that curcumin induces protection against OGD/R injury in HT22 cells, and SOD2 protein may mediate the protection.

The Influence of Cardiovascular Medications on Iron Metabolism in Patients with Heart Failure

Background and objectives: The etiology of anemia associated with heart failure is not fully understood, but there are data suggesting the involvement of multiple mechanisms, including various drug therapies used in patients with heart failure. Our primary objective was to evaluate the impact of beta blockers, angiotensin-converting enzyme inhibitors, and calcium-channel blockers on iron metabolism in patients with heart failure. Materials and Methods: This was a prospective observational study that included patients diagnosed with heart failure and iron deficiency (defined by ferritin <100 μg/L, or 100-300 μg/L with transferrin saturation <20%). Patients with anemia secondary to a known cause were excluded. Results: We found a statistically significant correlation between beta-blocker treatment and ferritin values (p = 0.02). Iron, hemoglobin, and hematocrit levels were significantly lower in the patients using calcium-channel blockers than those who were not. We also found a statistically significant indirect correlation (p = 0.04) between the use of angiotensin-converting enzyme inhibitors and hematocrit levels. Conclusion: The contribution of our study arises from the additional data regarding the drug-induced etiology of iron deficiency. Practitioners should be aware of the potential impact of therapeutic recommendations and this should imply a close monitoring of the biochemical parameters of iron deficiency in this category of patients.

AutophagySMDB: a curated database of small molecules that modulate protein targets regulating autophagy

Macroautophagy/autophagy is a complex self-degradative mechanism responsible for clearance of non functional organelles and proteins. A range of factors influences the autophagic process, and disruptions in autophagy-related mechanisms lead to disease states, and further exacerbation of disease. Despite in-depth research into autophagy and its role in pathophysiological processes, the resources available to use it for therapeutic purposes are currently lacking. Herein we report the Autophagy Small Molecule Database (AutophagySMDB; http://www.autophagysmdb.org/ ) of small molecules and their cognate protein targets that modulate autophagy. Presently, AutophagySMDB enlists ~10,000 small molecules which regulate 71 target proteins. All entries are comprised of information such as EC50 (half maximal effective concentration), IC50 (half maximal inhibitory concentration), Kd (dissociation constant) and Ki (inhibition constant), IUPAC name, canonical SMILE, structure, molecular weight, QSAR (quantitative structure activity relationship) properties such as hydrogen donor and acceptor count, aromatic rings and XlogP. AutophagySMDB is an exhaustive, cross-platform, manually curated database, where either the cognate targets for small molecule or small molecules for a target can be searched. This database is provided with different search options including text search, advanced search and structure search. Various computational tools such as tree tool, cataloging tools, and clustering tools have also been implemented for advanced analysis. Data and the tools provided in this database helps to identify common or unique scaffolds for designing novel drugs or to improve the existing ones for autophagy small molecule therapeutics. The approach to multitarget drug discovery by identifying common scaffolds has been illustrated with experimental validation. Abbreviations: AMPK: AMP-activated protein kinase; ATG: autophagy related; AutophagySMDB: autophagy small molecule database; BCL2: BCL2, apoptosis regulator; BECN1: beclin 1; CAPN: calpain; MTOR: mechanistic target of rapamycin kinase; PPARG: peroxisome proliferator activated receptor gamma; SMILES: simplified molecular input line entry system; SQSTM1: sequestosome 1; STAT3: signal transducer and activator of transcription.

A new ferrous diflunisal complex and its effects on biopools of labile iron

Drugs bearing metal-coordinating moieties can alter biological metal distribution. In this work, a complex between iron(II) and diflunisal was prepared in the solid state, exhibiting the following composition: [Fe(diflunisal)₂(H₂O)₂], (Fe(dif)₂). The ability of diflunisal to alter labile pools of both plasmatic and cellular iron was investigated in this work. We found out that diflunisal does not increase the levels of redox-active iron in plasma of iron overloaded patients. However, diflunisal efficiently carries iron into HeLa or HepG2 cells, inducing an iron-catalyzed oxidative stress.

A natural antioxidant, tannic acid mitigates iron-overload induced hepatotoxicity in Swiss albino mice through ROS regulation

Tannic acid (TA), a water soluble natural polyphenol with 8 gallic acids groups, is abundantly present in various medicinal plants. Previously TA has been investigated for its antimicrobial and antifungal properties. Being a large polyphenol, TA chelates more than 1 metal. Hence TA has been explored for potent antioxidant activities against reactive oxygen species (ROS), reactive nitrogen species (RNS) and as iron chelator in vitro thereby mitigating iron-overload induced hepatotoxicity in vivo. Iron dextran was injected intraperitoneally in Swiss albino mice to induce iron-overload triggered hepatotoxicity, followed by oral administration of TA for remediation. After treatment, liver, spleen, and blood samples were processed from sacrificed animals. The liver iron, serum ferritin, serum markers, ROS, liver antioxidant status, and liver damage parameters were assessed, followed by histopathology and protein expression studies. Our results show that TA is a prominent ROS and RNS scavenger as well as iron chelator in vitro. It also reversed the ROS levels in vivo and restricted the liver damage parameters as compared to the standard drug, desirox. Moreover, this natural polyphenol exclusively ameliorates the histopathological and fibrotic changes in liver sections reducing the iron-overload, along with chelation of liver iron and normalization of serum ferritin. The protective role of TA against iron-overload induced apoptosis in liver was further supported by changed levels of caspase 3, PARP as well as Bax/BCl-2 ratio. Thus, TA can be envisaged as a better orally administrable iron chelator to reduce iron-overload induced hepatotoxicity through ROS regulation.

Low hepcidin in liver fibrosis and cirrhosis; a tale of progressive disorder and a case for a new biochemical marker

Liver fibrosis is a precursor of liver cirrhosis, which is associated with increased mortality. Though liver biopsy remains the gold standard for the diagnosis of fibrosis, noninvasive biochemical methods are cost-effective, practical and are not linked with major risks of complications. In this respect, serum hepcidin, has emerged as a new marker of fibrosis and cirrhosis. In this review the discussion uncovers molecular links between hepcidin disturbance and liver fibrosis/cirrhosis. The discussion also expands on clinical studies that suggest that hepcidin can potentially be used as a biochemical parameter of fibrosis/cirrhosis and target of therapeutic strategies to treat liver diseases. The debatable issues such as the complicated nature of hepcidin disturbance in non-alcoholic liver disease, serum levels of hepcidin in acute hepatitis C virus infection, cause of hepcidin disturbance in autoimmune hepatitis and hepatic insulin resistance are discussed, with potential solutions unveiled in order to be studied by future research.