ROS generated by CYP450, especially CYP2E1, mediate mitochondrial dysfunction induced by tetrandrine in rat hepatocytes

A Comprehensive Appraisal of Bisbenzylisoquinoline Alkaloids Isolated From Genus Cyclea for Anticancer Potential

The pharmaceutical industry and academia are continuously searching for novel and effective anticancer lead compounds to ensure patient safety, provide a cure, and surpass all other obstacles. Given the indeterminate nature of cancer etiology, the importance of drugs capable of targeting multiple pathways cannot be overstated. Among naturally occurring compounds, bisbenzylisoquinoline (BBIQ) alkaloids, such as berberine, tetrandrine, chelidonine, and berbamine, have demonstrated significant anticancer potential by modulating diverse signaling pathways. Several of these compounds are currently in clinical trials, highlighting their relevance in cancer treatment. This review emphasizes the need for further investigation into the anticancer properties of BBIQ alkaloids, particularly those isolated from eight Cyclea species in India. With around 27 BBIQ alkaloids identified, these compounds hold promise, especially in combating multidrug resistance-a critical challenge in cancer therapy. Given the rising cancer incidence, these alkaloids warrant a deeper exploration of their therapeutic potential.

Azithromycin induces liver injury in mice by targeting the AMPK/Nrf2 pathway

BACKGROUND

Azithromycin is an antibacterial and anti-inflammatory drug widely used for the treatment of various diseases, including those caused by atypical pathogens, bacterial or viral infections, chronic sinusitis, and bronchial asthma, particularly in pediatric patients. However, concerns have emerged regarding its hepatotoxicity and its precise mechanism of action remains unclear.

OBJECTIVE

To investigate the molecular mechanisms responsible for azithromycin-induced acute liver injury to advance our understanding of the progression and pathogenesis of antibiotic-induced liver damage, and to improve prevention and treatment strategies.

MATERIALS AND METHODS

C57BL/6 mice, Nrf2-/- mice, and primary hepatocytes were used. Primary hepatocytes from mice were isolated using a two-step perfusion method and cultured in vitro via the 'sandwich' culture model.

RESULTS

The exposure to azithromycin resulted in increased apoptosis and reactive oxygen species (ROS) levels. In mouse models, intraperitoneal administration of azithromycin at varying concentrations and time points substantially induced hepatic disarray, swelling, and dysfunction. Azithromycin markedly upregulated the mRNA and protein levels of phosphorylated adenosine-activated protein kinase (AMPK) while downregulating nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase 1 (HO-1), and NADPH: quinone oxidoreductase 1 (NQO-1). Moreover, HO-1 and NQO-1 protein levels remained largely unaffected in primary hepatocytes co-cultured with azithromycin in Nrf2-/- mice.

CONCLUSIONS

Our findings suggest that azithromycin-induced acute liver injury is mediated by suppression of Nrf2 activation and ROS production. This sheds light on the potential mechanisms involved in azithromycin-induced liver damage, underscoring the importance of exploring targeted interventions to mitigate the hepatotoxic effects.

Response and defense mechanisms of the earthworms Eisenia foetida to natural saline soil stress

Salinization of soil is a serious global environmental issue, particularly in agricultural lands. Saline farmland not only endangers grain production but also affects the survival of soil fauna. Earthworms, as soil ecosystem engineers, play a crucial role in maintaining soil health and enhancing global agricultural production. However, the response of earthworms to natural saline soil stress remains poorly understood. To explore this, we investigated the effects of natural saline soil from Dongying City, Shandong Province, China, on the growth, survival, reproduction, antioxidation, and defense-related gene expression of the earthworm Eisenia foetida. Our findings demonstrate that the growth rate, survival rate, and cocoon production of E. foetida decrease under exposure to natural saline soil in a dose-dependent manner. Elevated levels of DNA damage in coelomocytes and increased reactive oxygen species (ROS) were observed. Additionally, antioxidant enzymes, such as superoxide dismutase (SOD) and catalase (CAT), increased under stress. The mRNA levels of Cyp450 and Hsp70 also rose in response to saline soil exposure. Furthermore, the activity of Na+/K+-ATPase and the expression of the osmotic sensor gene wnk-1 were elevated. In conclusion, our findings indicate that natural saline soil induces antioxidant and osmotic stress in earthworms E. foetida, highlighting the detrimental effects and defense mechanisms of soil fauna under such conditions.

Tetrandrine induces muscle atrophy involving ROS-mediated inhibition of Akt and FoxO3

Tetrandrine (Tet), a well-known drug of calcium channel blocker, has been broadly applied for anti-inflammatory and anti-fibrogenetic therapy. However, due to the functional diversity of ubiquitous calcium channels, potential side-effects may be expected. Our previous report revealed an inhibitory effect of Tet on myogenesis of skeletal muscle. Here, we found that Tet induced protein degradation resulting in the myofibril atrophy. Upon administration with a relative high dose (40 mg/kg) of Tet for 28 days, the mice displayed significantly reduced muscle mass, strength force, and myosin heavy chain (MyHC) protein levels. The MyHC reduction was further detected in C2C12 myotubes after treating with Tet. Interestingly, the expression of Atrogin-1 and Murf-1, the skeletal muscle specific E3 ligases of protein ubiquitin-proteasome system (UPS), was accordingly up-regulated, and the reduced MyHC was significantly mitigated by MG132, a 26S proteasome inhibitor, indicating a key role of UPS in the protein degradation of muscle cells. Further study showed that Tet induced autophagy also participated in the protein degradation. Mechanistically, Tet treatment caused ROS production in myotubes that in turn targeted on FoxO3/AKT signaling, resulting in the activation of UPS and autophagy processes that were involved in the protein degradation. Our study reveals a potential side-effect of Tet on skeletal muscle atrophy, particularly when the drug dose is relatively high.

CYP14 family in Caenorhabditis elegans: Mitochondrial function, detoxification, and lifespan

CYP-14 members of the Caenorhabditis elegans (C. elegans) Cytochrome P450 (CYP) enzyme family, plays important roles in mitochondrial dysfunction, detoxification, lipid metabolism, defense and lifespan regulation. The review identifies CYP-14 members: cyp-14A1, cyp-14A2, cyp-14A3, cyp-14A4, cyp-14A5 and their homology with human CYP families. Despite limited studies on C. elegans cyp-14 members, the findings unraveled their complex crosstalk between mitochondrial stress, detoxification mechanisms, and lifespan regulation, emphasizing the complexity of these interconnected pathways as well as how their regulation depends on environmental cues changes including pH, nutrients, ROS and chemical stressors. The review underscores the translational relevance to human health, shedding light on potential human homologues and their implications in age-related, metabolic and respiratory diseases. Among other genes, cyp-14A2 and cyp-14A4 predominate the mitochondrial function, heat resistance, lipid metabolism, detoxification and lifespan pathways. In conclusion, these insights pave the way for future research, offering promising avenues for therapeutic interventions targeting CYP-14 activity to address age-related diseases and promote healthy aging.

Mass spectrometry imaging as a promising analytical technique for herbal medicines: an updated review

Herbal medicines (HMs) have long played a pivotal role in preventing and treating various human diseases and have been studied widely. However, the complexities present in HM metabolites and their unclear mechanisms of action have posed significant challenges in the modernization of traditional Chinese medicine (TCM). Over the past two decades, mass spectrometry imaging (MSI) has garnered increasing attention as a robust analytical technique that enables the simultaneous execution of qualitative, quantitative, and localization analyses without complex sample pretreatment. With advances in technical solutions, MSI has been extensively applied in the field of HMs. MSI, a label-free ion imaging technique can comprehensively map the spatial distribution of HM metabolites in plant native tissues, thereby facilitating the effective quality control of HMs. Furthermore, the spatial dimension information of small molecule endogenous metabolites within animal tissues provided by MSI can also serve as a supplement to uncover pharmacological and toxicological mechanisms of HMs. In the review, we provide an overview of the three most common MSI techniques. In addition, representative applications in HM are highlighted. Finally, we discuss the current challenges and propose several potential solutions. We hope that the summary of recent findings will contribute to the application of MSI in exploring metabolites and mechanisms of action of HMs.

Tetrandrine inhibits aldosterone synthesis by covalently targeting CYP11A1 to attenuate hypertension

Introduction

Tetrandrine (Tet) is the main pharmacological component of Stephania tetrandra S. Moore, which is a well-documented traditional Chinese medicine known for its diuretic and antihypertensive properties. Unraveling the specific targets and mechanisms of Tet involved in inducing diuresis and mitigating hypertension can provide valuable insights into its therapeutic effects. This study aimed to explore the diuretic and antihypertensive targets and mechanisms of Tet using chemical biology coupled with activity analyses in vivo and in vitro.

Methods

The diuretic effects of Tet were evaluated using a water-loaded mouse model. The direct target proteins for the diuretic and antihypertensive effects of Tet were determined using chemical biology. Furthermore, the molecular mechanism of Tet binding to target proteins was analyzed using a multidisciplinary approach based on the structure and function of the proteins. Finally, the effects of the Tet-targeted protein on downstream signaling pathways and blood pressure were evaluated in hypertensive model rats.

Results

Tet exhibited significant antihypertensive and potassium-preserving diuretic effects. The mechanism underlying these effects involves the modulation of the enzyme activity by covalent binding of Tet to Cys423 of CYP11A1. This interaction alters the stability of heme within CYP11A1, subsequently impeding electron transfer and inhibiting aldosterone biosynthesis.

Discussion

This study not only revealed the mechanism of the diuretic and antihypertensive effects of Tet but also discovered a novel covalent inhibitor of CYP11A1. These findings contribute significantly to our understanding of the therapeutic potential of Tet and provide a foundation for future research in the development of targeted treatments for hypertension.

IL-6 Mutation Attenuates Liver Injury Caused by Aeromonas hydrophila Infection by Reducing Oxidative Stress in Zebrafish

Interleukin-6 (IL-6), a pleiotropic cytokine, plays a crucial role in acute stress induced by bacterial infection and is strongly associated with reactive oxygen species (ROS) production. However, the role of IL-6 in the liver of fish after Aeromonas hydrophila infection remains unclear. Therefore, this study constructed a zebrafish (Danio rerio) il-6 knockout line by CRISPR/Cas9 to investigate the function of IL-6 in the liver post bacterial infection. After infection with A. hydrophila, pathological observation showed that il-6-/- zebrafish exhibited milder liver damage than wild-type (WT) zebrafish. Moreover, liver transcriptome sequencing revealed that 2432 genes were significantly up-regulated and 1706 genes were significantly down-regulated in il-6-/- fish compared with WT fish after A. hydrophila infection. Further, gene ontology (GO) analysis showed that differentially expressed genes (DEGs) were significantly enriched in redox-related terms, including oxidoreductase activity, copper ion transport, etc. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that DEGs were significantly enriched in pathways such as the PPAR signaling pathway, suggesting that il-6 mutation has a significant effect on redox processes in the liver after A. hydrophila infection. Additionally, il-6-/- zebrafish exhibited lower malondialdehyde (MDA) levels and higher superoxide dismutase (SOD) activities in the liver compared with WT zebrafish following A. hydrophila infection, indicating that IL-6 deficiency mitigates oxidative stress induced by A. hydrophila infection in the liver. These findings provide a basis for further studies on the role of IL-6 in regulating oxidative stress in response to bacterial infections.

Oligonol ameliorates liver function and brain function in the 5 × FAD mouse model: transcriptional and cellular analysis

Alzheimer's disease (AD) is a common neurodegenerative disease worldwide and is accompanied by memory deficits, personality changes, anxiety, depression, and social difficulties. For treatment of AD, many researchers have attempted to find medicinal resources with high effectiveness and without side effects. Oligonol is a low molecular weight polypeptide derived from lychee fruit extract. We investigated the effects of oligonol in 5 × FAD transgenic AD mice, which developed severe amyloid pathology, through behavioral tests (Barnes maze, marble burying, and nestle shredding) and molecular experiments. Oligonol treatment attenuated blood glucose levels and increased the antioxidant response in the livers of 5 × FAD mice. Moreover, the behavioral score data showed improvements in anxiety, depressive behavior, and cognitive impairment following a 2-month course of orally administered oligonol. Oligonol treatment not only altered the circulating levels of cytokines and adipokines in 5 × FAD mice, but also significantly enhanced the mRNA and protein levels of antioxidant enzymes and synaptic plasticity in the brain cortex and hippocampus. Therefore, we highlight the therapeutic potential of oligonol to attenuate neuropsychiatric problems and improve memory deficits in the early stage of AD.

Detrimental consequences of tebuconazole on redox homeostasis and fatty acid profile of honeybee brain

Excessive use of azole fungicides in agriculture poses a potential threat to honeybees and other pollinator insects; however, the detailed effects of these molecules remain largely unclear. Hence, in the present study it was aimed to investigate the acute sublethal effects of tebuconazole on the redox homeostasis and fatty acid composition in the brain of honeybees. Our findings demonstrate that tebuconazole decreased total antioxidant capacity, the ratio of reduced to oxidized glutathione and disturbed the function of key antioxidant defense enzymes along with the induction of lipid peroxidation indicated by increased malondialdehyde levels, while it also altered the fatty acid profile of the brain. The present study highlights the negative impact of tebuconazole on honeybees and contributes to the understanding of potential consequences related to azole exposure on pollinator insects' health, such as the occurrence of colony collapse disorder.

miR-1273h-5p protects the human corneal epithelium against UVR-induced oxidative stress and apoptosis: Role of miR-1273h-5p in climatic droplet keratopathy

Climatic droplet keratopathy (CDK) is characterized by an increased number of oil-like deposits on the most anterior corneal layers, which affect vision and can cause blindness. Environmental ultraviolet radiation (UVR) exposure is a major risk factor, but the underlying mechanism of CDK pathogenesis is unclear. Increasing evidence has demonstrated that miRNAs participate in the cross-talk with oxidative stress. We aimed to explore whether certain miRNAs are involved in the pathogenesis of CDK. We performed miRNA sequencing of tears from patients with CDK and healthy individuals from Tacheng region of Xinjiang and conducted bioinformatic analysis of key miRNAs. We also evaluated viability, migration, and apoptosis of human corneal epithelial cells (HCECs) subjected to UVR treatment. miR-1273h-5p expression was abnormally downregulated in the tears of patients with CDK. miR-1273h-5p promoted cell proliferation and migration and inhibited UVR-induced mitochondrial apoptosis. miR-1273h-5p protected HCECs against UVR-induced oxidative damage by reducing the accumulation of reactive oxygen species and inhibiting mitochondrial apoptosis via the activation of the Nrf2 pathway. Thus, our results suggest that miR-1273h-5p protects the corneal epithelium against UVR-induced oxidative stress damage.

ZiBuPiYin recipe ameliorates diabetes-associated cognitive decline by improving neuronal mitochondrial function in chronic psychologically stressed zucker diabetic fatty rats

ETHNOPHARMACOLOGICAL RELEVANCE

Zibu Piyin Recipe (ZBPYR) is a traditional Chinese medicine compound composed of 12 kinds of Chinese herbal medicines including red ginseng and yam. Long-term basic and clinical applications have proved that ZBPYR can prevent and treat cognitive dysfunction. Previous studies showed that chronic psychological stress can increase the risk of type 2 diabetes mellitus (T2DM), and lead to cognitive decline. Mitochondrial dysfunction plays a key role in chronic psychological stress-induced diabetes mellitus. While the mechanism of mitochondrial dysfunction and insulin resistance in diabetes-associated cognitive decline (DACD) is unclear.

AIM OF THE STUDY

Our previous research found that a ZiBuPiYin recipe (ZBPYR) has significant pharmacological effects against DACD. The present study investigated changes in mitochondrial dysfunction in the brain and the mechanism of insulin resistance and mitochondrial damage to explore the relationship between neuronal mitochondrial dysfunction and insulin resistance in chronic psychologically stressed DACD rats.

MATERIALS AND METHODS

Zucker diabetic fatty (ZDF) rats with spontaneous T2DM and rats with diabetic cognitive impairment that was induced by chronic psychological stress were used in in vivo experiments. PC12 cells that were damaged by rotenone were used for the in vitro experiment.

RESULTS

The findings indicated that the number of mitochondria decreased, morphology and membrane potential were damaged, and reactive oxygen species increased in the cortex and hippocampus in psychologically stressed DACD rats. Protein kinase Cβ2 (PKCβ2) activation and insulin resistance were markedly induced by chronic psychological stress, together with decreases in peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) and mitochondrial fusion protein 2 (Mfn2). Furthermore, ZBPYR exerted protective effects both in in vivo and in vitro.

CONCLUSION

Mitochondrial damage and insulin resistance were observed in the brain in chronic psychologically stressed DACD rats. The ZBPYR significantly improved brain mitochondrial damage and insulin resistance in chronic psychologically stressed DACD rats. These results provide novel insights for the development of ZBPYR as a traditional Chinese medicine for the treatment of chronic psychological stress and DACD.

Combined exposure to di(2-ethylhexyl) phthalate and polystyrene microplastics induced renal autophagy through the ROS/AMPK/ULK1 pathway

Di(2-ethylhexyl) phthalate (DEHP) and polystyrene microplastics (PS-MPs) are new environmental pollutants that attracted increased attention. At present, the effects and underlying mechanisms of action of combined exposure of DEHP and PS-MPs on the kidney have not been elucidated. To investigate the renal toxicity of DEHP and PS-MPs exposure, we established single and combined DEHP and PS-MPs exposure models in mice and HEK293 cells, respectively. Hematoxylin and eosin staining, transmission electron microscopy, monodansylcadaverine staining, immunofluorescence, real-time quantitative PCR, Western blot analysis and other methods were used to detect relevant indicators. The results showed that the expression levels of ROS/AMPK/ULK1 and Ppargc1α/Mfn2 signaling pathway-related genes were significantly increased in the DEHP and PS-MPs exposure models. The mRNA and protein expression levels of autophagy markers were also upregulated. In addition, we found that the expression levels of mRNAs and proteins in the combined exposure group were more significantly increased than those in the single exposure group. In conclusion, combined exposure to DEHP and PS-MPs caused oxidative stress and activated the AMPK/ULK1 pathway, thereby inducing renal autophagy. Our results enhance the field of nephrotoxicity studies of plasticizers and microplastics and provide new light on combined toxicity studies of DEHP and PS-MPs.

Hernandezine induces autophagic cell death in human pancreatic cancer cells via activation of the ROS/AMPK signaling pathway

Hernandezine (Her) is a bisbenzylisoquinoline alkaloid extracted from the traditional Chinese herbal medicine Thalictrum glandulosissimum. Evidence shows that Her is a natural agonist of adenosine monophosphate (AMP)-activated protein kinase (AMPK) and induces apoptosis and autophagy in tumor cells. In this study, we investigated the role of autophagy in Her-induced cell death in human pancreatic cancer cell lines. We showed that Her dose-dependently suppressed cell proliferation, promoted autophagy and induced autophagic death in pancreatic ductal adenocarcinoma (PDAC) cell lines Capan-1 and SW1990. The IC50 values of Her in inhibition of Capan-1 and SW1990 cells were 47.7 μM and 40.1 μM, respectively. Immunoblotting showed that Her (1−40 μM) promoted the conversion of LC3-I to LC3-II, and Her exerted concentration-dependent and time-dependent effects on autophagy activation in PDAC cells. In transmission electron microscopy and fluorescence image analysis, we found that autophagic vacuoles were significantly increased in Her-treated cells. Knockdown of ATG5, a key gene in the autophagy pathway, alleviated the activation of autophagy by Her. These results demonstrated that Her induced autophagy in PDAC cells. Intensely activated autophagy could promote cell death. The autophagy inhibitors, BafA1 and HCQ significantly inhibited Her-induced cell death, implying that Her induced autophagic cell death in PDAC cells. Moreover, we showed that Her activated autophagy by increasing the phosphorylation of AMPK and decreasing the phosphorylation of mTOR/p70S6K. Knockdown of AMPKα relieves the autophagic cell death induced by Her. Furthermore, Her concentration-dependently enhanced reactive oxygen species (ROS) generation in PDAC cells. Antioxidants could reduce the phosphorylation of AMPK and suppress autophagic cell death induced by Her. Our study provides evidence for the development of Her as a therapeutic agent for the treatment of pancreatic cancer.

Anti-hyperprolactinemic activities of aqueous extract of Uvaria chamae (P. Beauv) roots and associated biochemical changes in chlorpromazine-induced hyperprolactinemic female Wistar rats

ETHNOPHARAMCOLOGICAL RELEVANCE

The age-long folkloric use of Uvaria chamae roots in the management of nipple discharge that is not related to pregnancy, childbirth or nursing but as a result of excessive production of prolactin (hyperprolactinemia) is yet to be substantiated with scientific data.

AIM OF THE STUDY

This study investigated the anti-hyperprolactinemic activities of aqueous extract of Uvaria chamae roots (AEUCR) and associated biochemical changes in chlorpromazine (CPZ)-induced hyperprolactinemic female Wistar rats.

MATERIALS AND METHODS

A total of sixty female rats (207.40 ± 2.69 g) were assigned into 6 groups: A-F. Animals in Group A received 0.5 ml of distilled water only whilst the 7 days CPZ-treated female rats (to induce hyperprolactinemia) in groups B, C, D, E, and F also received distilled water, 2.5 mg/kg body weight of bromocriptine (reference drug), 0.71, 1.41 2.83 mg/kg body weight of AEUCR for 28 days.

RESULTS

AEUCR contained a total of 15 (75%) amino acids with seven (46.67%) being essential amino acids and eight (53.33%) as non-essential amino acids. Administration of CPZ increased (p < 0.05) the levels of prolactin and testosterone, and reduced (p < 0.05) the levels of estradiol, progesterone, follicle stimulating hormone (FSH), luteinizing hormone (LH), dopamine, triiodothyronine (T3) and tetraiodothyroxine (T4). Chlorpromazine also increased the levels of serum urea, creatinine, total protein, albumin, globulin, bilirubin, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) of the animals. In contrast, AEUCR significantly (p < 0.05) reduced the CPZ-induced increases in the levels of prolactin and testosterone, and increased the levels of CPZ-induced reduction in the progesterone, estradiol, FSH, LH, dopamine, T3 and T4. The AEUCR also reversed (p < 0.05) the CPZ-induced related increases in the levels of urea, creatinine, total protein, albumin, globulin, bilirubin, ALT, AST and ALP similar to the trends in the distilled water- and bromocriptine-treated controls. The CPZ-induced remarkable increase in the size of lactating alveolus and lactiferous duct distribution in the mammary gland were restored to normal tubule-alveolar female pattern mammary glands, composed of branching ducts and small alveoli budding off the ducts.

CONCLUSION

The study concluded that aqueous extract of Uvaria chamae root exhibited anti-hyperprolactinemic activity by restoring prolactin and dopamine levels and tubule-alveolar female pattern in female rats. It also ameliorated CPZ-induced changes in the liver and kidney function indices. This study justifies the folkloric use of Uvaria chamae root in the management of abnormal discharge by the nipples that is unrelated to pregnancy, childbirth and nursing.

Thirteen bisbenzylisoquinoline alkaloids in five Chinese medicinal plants: Botany, traditional uses, phytochemistry, pharmacokinetic and toxicity studies

RELEVANCE

Bisbenzylisoquinoline (BBIQ) alkaloids are generally present in plants of Berberidaceae, Monimiaceae and Ranunculaceae families in tropical and subtropical regions. Some species of these families are used in traditional Chinese medicine, with the effects of clearing away heat and detoxification, promoting dampness and defecation, and eliminating sores and swelling. This article offers essential data focusing on 13 representative BBIQ compounds, which are mainly extracted from five plants. The respective botany, traditional uses, phytochemistry, pharmacokinetics, and toxicity are summarized comprehensively. In addition, the ADME prediction of the 13 BBIQ alkaloids is compared and analyzed with the data obtained.

MATERIALS AND METHODS

We have conducted a systematic review of the botanical characteristics, traditional uses, phytochemistry, pharmacokinetics and toxicity of BBIQ alkaloids based on literatures collected from PubMed, Web of Science and Elsevier during 1999-2020. ACD/Percepta software was utilized to predict the pharmacokinetic parameters of BBIQ alkaloids and their affinity with enzymes and transporters.

RESULTS

Botany, traditional uses, phytochemistry, pharmacokinetic and toxicity of 13 alkaloids, namely, tetrandrine, dauricine, curine, trilobine, isotrilobine, cepharanthine, daurisoline, thalicarpine, thalidasine, isotetrandrine, liensinine, neferine and isoliensinine, have been summarized in this paper. It can't be denied that these alkaloids are important material basis of pharmacological effects of family Menispermaceae and others, and for traditional and local uses which has been basically reproduced in the current studies. The 13 BBIQ alkaloids in this paper showed strong affinity and inhibitory effect on P-glycoprotein (P-gp), with poor oral absorption and potent binding ability with plasma protein. BBIQ alkaloids represented by tetrandrine play a key role in regulating P-gp or reversing multidrug resistance (MDR) in a variety of tumors. The irrationality of their usage could pose a risk of poisoning in vivo, including renal and liver toxicity, which are related to the formation of quinone methide during metabolism.

CONCLUSION

Although there is no further clinical evaluation of BBIQ alkaloids as MDR reversal agents, their effects on P-gp should not be ignored. Considering their diverse distribution, pharmacokinetic characteristics and toxicity reported during clinical therapy, the quality standards in different plant species and the drug dosage remain unresolved problems.

Gene editing and synthetically accessible inhibitors reveal role for TPC2 in HCC cell proliferation and tumor growth

The role of two-pore channel 2 (TPC2), one of the few cation channels localized on endolysosomal membranes, in cancer remains poorly understood. Here, we report that TPC2 knockout reduces proliferation of cancer cells in vitro, affects their energy metabolism, and successfully abrogates tumor growth in vivo. Concurrently, we have developed simplified analogs of the alkaloid tetrandrine as potent TPC2 inhibitors by screening a library of synthesized benzyltetrahydroisoquinoline derivatives. Removal of dispensable substructures of the lead molecule tetrandrine increases antiproliferative properties against cancer cells and impairs proangiogenic signaling of endothelial cells to a greater extent than tetrandrine. Simultaneously, toxic effects on non-cancerous cells are reduced, allowing in vivo administration and revealing a TPC2 inhibitor with antitumor efficacy in mice. Hence, our study unveils TPC2 as valid target for cancer therapy and provides easily accessible tetrandrine analogs as a promising option for effective pharmacological interference.

Autophagy mitigates ethanol-induced mitochondrial dysfunction and oxidative stress in esophageal keratinocytes

During alcohol consumption, the esophageal mucosa is directly exposed to high concentrations of ethanol (EtOH). We therefore investigated the response of normal human esophageal epithelial cell lines EPC1, EPC2 and EPC3 to acute EtOH exposure. While these cells were able to tolerate 2% EtOH for 8 h in both three-dimensional organoids and monolayer culture conditions, RNA sequencing suggested that EtOH induced mitochondrial dysfunction. With EtOH treatment, EPC1 and EPC2 cells also demonstrated decreased mitochondrial ATPB protein expression by immunofluorescence and swollen mitochondria lacking intact cristae by transmission electron microscopy. Mitochondrial membrane potential (ΔΨm) was decreased in a subset of EPC1 and EPC2 cells stained with ΔΨm–sensitive dye MitoTracker Deep Red. In EPC2, EtOH decreased ATP level while impairing mitochondrial respiration and electron transportation chain functions, as determined by ATP fluorometric assay, respirometry, and liquid chromatography-mass spectrometry. Additionally, EPC2 cells demonstrated enhanced oxidative stress by flow cytometry for mitochondrial superoxide (MitoSOX), which was antagonized by the mitochondria-specific antioxidant MitoCP. Concurrently, EPC1 and EPC2 cells underwent autophagy following EtOH exposure, as evidenced by flow cytometry for Cyto-ID, which detects autophagic vesicles, and immunoblots demonstrating induction of the lipidated and cleaved form of LC3B and downregulation of SQSTM1/p62. In EPC1 and EPC2, pharmacological inhibition of autophagy flux by chloroquine increased mitochondrial oxidative stress while decreasing cell viability. In EPC2, autophagy induction was coupled with phosphorylation of AMP activated protein kinase (AMPK), a cellular energy sensor responding to low ATP levels, and dephosphorylation of downstream substrates of mechanistic Target of Rapamycin Complex (mTORC)-1 signaling. Pharmacological AMPK activation by AICAR decreased EtOH-induced reduction of ΔΨm and ATP in EPC2. Taken together, acute EtOH exposure leads to mitochondrial dysfunction and oxidative stress in esophageal keratinocytes, where the AMPK-mTORC1 axis may serve as a regulatory mechanism to activate autophagy to provide cytoprotection against EtOH-induced cell injury.

Synthesis, biological evaluation and toxicity of novel tetrandrine analogues

In this work, we present the design and synthesis of novel fully synthetic analogues of the bisbenzylisoquinoline tetrandrine, a molecule with numerous pharmacological properties and the potential to treat life-threatening diseases, such as viral infections and cancer. Its toxicity to liver and lungs and the underlying mechanisms, however, are controversially discussed. Along this line, novel tetrandrine analogues were synthesized and biologically evaluated for their hepatotoxicity, as well as their antiproliferative and chemoresistance reversing activity on cancer cells. Previous studies suggesting CYP-mediated toxification of tetrandrine prompted us to amend/replace the suspected metabolically instable 12-methoxy group. Of note, employing several in vitro models showed that the proposed CYP3A4-driven metabolism of tetrandrine and analogues is not the major cause of hepatotoxicity. Biological characterization revealed that some of the novel tetrandrine analogues sensitized drug-resistant leukemia cells by inhibition of the P-glycoprotein. Interestingly, direct anticancer effects improved in comparison to tetrandrine, as several compounds displayed a markedly enhanced ability to reduce proliferation of drug-resistant leukemia cells and to induce cell death of liver cancer cells. Those enhanced anticancer properties were linked to influences on activation of the kinase Akt and mitochondrial events. In sum, our study clarifies the role of CYP3A4-mediated toxicity of the bisbenzylisoquinoline alkaloid tetrandrine and provides the basis for the exploitation of novel synthetic analogues for their antitumoral potential.

Higher sensitivity of female cells to ethanol: methylation of DNA lowers Cyp2e1, generating more ROS

Background

Cells taken from mouse embryos before sex differentiation respond to insults according to their chromosomal sex, a difference traceable to differential methylation. We evaluated the mechanism for this difference in the controlled situation of their response to ethanol.

Methods

We evaluated the expression of mRNA for alcohol dehydrogenase (ADH), aldehyde dehyrogenases (ALDH), and a cytochrome P450 isoenzyme (Cyp2e1) in male and female mice, comparing the expressions to toxicity under several experimental conditions evaluating redox and other states.

Results

Females are more sensitive to ethanol. Disulfiram, which inhibits alcohol dehydrogenase (ADH), increases cell death in males, eliminating the sex dimorphism. The expressions ADH Class 1 to 4 and ALDH Class 1 and 2 do not differ by sex. However, females express approximately 8X more message for Cyp2e1, an enzyme in the non-canonical pathway. Female cells produce approximately 15% more ROS (reactive oxygen species) than male cells, but male cells contain approximately double the concentration of GSH, a ROS scavenger. Scavenging ROS with N-acetyl cysteine reduces cell death and eliminates sex dimorphism. Finally, since many of the differences in gene expression derive from methylation of DNA, we exposed cells to the methyltransferase inhibitor 5-aza- 2-deoxycytidine; blocking methylation eliminates both the difference in expression of Cyp2e1 and cell death.

Conclusion

We conclude that the sex-differential cell death caused by ethanol derives from sex dimorphic methylation of Cyp2e1 gene, resulting in generation of more ROS.

A critical review: traditional uses, phytochemistry, pharmacology and toxicology of Stephania tetrandra S. Moore (Fen Fang Ji)

ABSTRACT

Stephania tetrandra S. Moore (S. tetrandra) is distributed widely in tropical and subtropical regions of Asia and Africa. The root of this plant is known in Chinese as "Fen Fang Ji". It is commonly used in traditional Chinese medicine to treat arthralgia caused by rheumatism, wet beriberi, dysuria, eczema and inflamed sores. Although promising reports have been published on the various chemical constituents and activities of S. tetrandra, no review comprehensively summarizes its traditional uses, phytochemistry, pharmacology and toxicology. Therefore, the review aims to provide a critical and comprehensive evaluation of the traditional use, phytochemistry, pharmacological properties, pharmacokinetics and toxicology of S. tetrandra in China, and meaningful guidelines for future investigations.

Methionine Adenosyltransferase α1 Is Targeted to the Mitochondrial Matrix and Interacts with Cytochrome P450 2E1 to Lower Its Expression

Methionine adenosyltransferase α1 (MATα1, encoded by MAT1A) is responsible for hepatic biosynthesis of S-adenosyl methionine, the principal methyl donor. MATα1 also act as a transcriptional cofactor by interacting and influencing the activity of several transcription factors. Mat1a knockout (KO) mice have increased levels of cytochrome P450 2E1 (CYP2E1), but the underlying mechanisms are unknown. The aims of the current study were to identify binding partners of MATα1 and elucidate how MATα1 regulates CYP2E1 expression. We identified binding partners of MATα1 by coimmunoprecipitation (co-IP) and mass spectrometry. Interacting proteins were confirmed using co-IP using recombinant proteins, liver lysates, and mitochondria. Alcoholic liver disease (ALD) samples were used to confirm relevance of our findings. We found that MATα1 negatively regulates CYP2E1 at mRNA and protein levels, with the latter being the dominant mechanism. MATα1 interacts with many proteins but with a predominance of mitochondrial proteins including CYP2E1. We found that MATα1 is present in the mitochondrial matrix of hepatocytes using immunogold electron microscopy. Mat1a KO hepatocytes had reduced mitochondrial membrane potential and higher mitochondrial reactive oxygen species, both of which were normalized when MAT1A was overexpressed. In addition, KO hepatocytes were sensitized to ethanol and tumor necrosis factor α-induced mitochondrial dysfunction. Interaction of MATα1 with CYP2E1 was direct, and this facilitated CYP2E1 methylation at R379, leading to its degradation through the proteasomal pathway. Mat1a KO livers have a reduced methylated/total CYP2E1 ratio. MATα1's influence on mitochondrial function is largely mediated by its effect on CYP2E1 expression. Patients with ALD have reduced MATα1 levels and a decrease in methylated/total CYP2E1 ratio. Conclusion: Our findings highlight a critical role of MATα1 in regulating mitochondrial function by suppressing CYP2E1 expression at multiple levels.

Molecular mechanisms involved in drug-induced liver injury caused by urate-lowering Chinese herbs: A network pharmacology study and biology experiments

As an important part of the comprehensive treatment methods, the urate-lowering Chinese herbs could provide favorable clinical effects on hyperuricemia in its ability to invigorate spleen and remove dampness. Owing to the long-term duration, it brought up the potential adverse reactions (ADRs) and concerns about the drug-induced liver injury from these herbs. To address this problem, the bioinformatics approaches which combined the network pharmacology, computer simulation and molecular biology experiments were undertaken to elucidate the underlying drug-induced liver injury molecular mechanisms of urate-lowering Chinese herbs. Several electronic databases were searched to identify the potential liver injury compounds in published research. Then, the putative target profile of liver injury was predicted, and the interaction network was constructed based on the links between the compounds, corresponding targets and core pathways. Accordingly, the molecular docking simulation was performed to recognize the representative compounds with hepatotoxicity. Finally, the cell experiments were conducted to investigate the biochemical indicators and expression of the crucial protein that were closely associated with liver injury. In conclusion, the current research revealed that the compounds with potential liver injury including diosgenin, baicalin, saikosaponin D, tetrandrine, rutaecarpine and evodiamine from urate-lowering Chinese herbs, could lead to decline the survival rate of L-02 cell, increase the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) in cell-culture medium, enhance the expression of p-p38/p38, while the p38 inhibitor could achieve the trend of regulating and controlling liver injury. These research findings bring further support to the growing evidence that the mechanism of the liver injury induced by the compounds from urate-lowering Chinese herbs may be associated with the activation of p38α.

Quantitative MALDI Imaging of Spatial Distributions and Dynamic Changes of Tetrandrine in Multiple Organs of Rats

Detailed spatio-temporal information on drug distribution in organs is of paramount importance to assess drug clinically-relevant properties and potential side-effects. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) as a label-free and sensitive imaging modality provides an additional means of accurately visualizing drug and its metabolites distributions in tissue sections. However, technical limitations, complex physiochemical environment of surface and low abundance of target drugs make quantitative MALDI imaging of drug and its metabolites quite challenging.

Methods: In this study, an internal standard correction strategy was applied for quantitative MALDI imaging of tetrandrine in multiple organs of rats including lung, liver, kidney, spleen, and heart. The feasibility and reliability of the developed quantitative MSI method were validated by conventional liquid chromatography-tandem MS (LC-MS/MS) analysis, and the two methods showed a significant correlation.

Results: The quantitative MALDI imaging method met the requirements of specificity, sensitivity and linearity. Tissue-specific spatio-temporal distribution patterns of tetrandrine in different organs were revealed after intravenous administration in the rat. Moreover, demethylated metabolite was detected in liver tissues.

Conclusions: The current work illustrates that quantitative MALDI imaging provides an alternative means of accurately addressing the problem of drug and its metabolites distribution in tissues, complementary to traditional LC-MS/MS of tissue homogenates and whole-body autoradiography (WBA). Quantitative spatio-chemical information obtained here can improve our understanding of pharmacokinetics (PK), pharmacodynamics (PD), and potential transient toxicities of tetrandrine in organs, and possibly direct further optimization of drug properties to reduce drug-induced organ toxicity.

Enhancing tetrandrine cytotoxicity in human lung carcinoma A549 cells by suppressing mitochondrial ATP production

ATP depletion induced by inhibiting glycolysis or mitochondrial ATP production has been demonstrated to cause cancer cell death. Whether ATP depletion can enhance the efficacy and potency of anti-cancer effects of herbal compounds is so far unknown. We examined the enhancing effect of ATP depletion on anti-cancer actions of tetrandrine (TET) in human lung carcinoma A549 cells. A 24-h incubation of A549 cells with tetrandrine caused a concentration-dependent cytotoxic effect (LC₅₀ = 66.1 μM). Co-incubation with 20 mM 2-deoxyglucose (2-DG, glycolysis inhibitor) caused only a very slight enhancement of tetrandrine cytotoxicity. By contrast, inhibiting mitochondrial ATP production with oligomycin (10 μM, ATP synthase inhibitor) and FCCP (30 μM, uncoupling agent) (thus, oligo-FCCP) on its own caused only slight cell cytotoxicity but strongly potentiated tetrandrine cytotoxicity (tetrandrine LC₅₀ = 15.6 μM). The stronger enhancing effect of oligo-FCCP than 2-DG on TET toxicity did not result from more severe overall ATP depletion, since both treatments caused a similar ATP level suppression. Neither oligo-FCCP nor 2-DG synergized with tetrandrine in decreasing mitochondrial membrane potential. TET on its own triggered reactive oxygen species (ROS) production, and oligo-FCCP, but not 2-DG, potentiated TET in causing ROS production. Taken together, our results suggest that inhibiting ATP production from mitochondria, but not from glycolysis, appears to be a very effective means in augmenting TET-triggered ROS production and hence toxicity in A549 cells.

Molecular Mechanisms Involved in Oxidative Stress-Associated Liver Injury Induced by Chinese Herbal Medicine: An Experimental Evidence-Based Literature Review and Network Pharmacology Study

Oxidative stress, defined as a disequilibrium between pro-oxidants and antioxidants, can result in histopathological lesions with a broad spectrum, ranging from asymptomatic hepatitis to hepatocellular carcinoma in an orchestrated manner. Although cells are equipped with sophisticated strategies to maintain the redox biology under normal conditions, the abundance of redox-sensitive xenobiotics, such as medicinal ingredients originated from herbs or animals, can dramatically invoke oxidative stress. Growing evidence has documented that the hepatotoxicity can be triggered by traditional Chinese medicine (TCM) during treating various diseases. Meanwhile, TCM-dependent hepatic disorder represents a strong correlation with oxidative stress, especially the persistent accumulation of intracellular reactive oxygen species. Of note, since TCM-derived compounds with their modulated targets are greatly diversified among themselves, it is complicated to elaborate the potential pathological mechanism. In this regard, data mining approaches, including network pharmacology and bioinformatics enrichment analysis have been utilized to scientifically disclose the underlying pathogenesis. Herein, top 10 principal TCM-modulated targets for oxidative hepatotoxicity including superoxide dismutases (SOD), malondialdehyde (MDA), glutathione (GSH), reactive oxygen species (ROS), glutathione peroxidase (GPx), Bax, caspase-3, Bcl-2, nuclear factor (erythroid-derived 2)-like 2 (Nrf2), and nitric oxide (NO) have been identified. Furthermore, hepatic metabolic dysregulation may be the predominant pathological mechanism involved in TCM-induced hepatotoxic impairment.

Tetrandrine, a Chinese plant-derived alkaloid, is a potential candidate for cancer chemotherapy

Cancer is a disease caused by the abnormal proliferation and differentiation of cells governed by tumorigenic factors. Chemotherapy is one of the major cancer treatment strategies, and it functions by targeting the physiological capabilities of cancer cells, including sustained proliferation and angiogenesis, the evasion of programmed cell death, tissue invasion and metastasis. Remarkably, natural products have garnered increased attention in the chemotherapy drug discovery field because they are biologically friendly and have high therapeutic effects. Tetrandrine, isolated from the root of Stephania tetrandra S Moore, is a traditional Chinese clinical agent for silicosis, autoimmune disorders, inflammatory pulmonary diseases, cardiovascular diseases and hypertension. Recently, the novel anti-tumor effects of tetrandrine have been widely investigated. More impressive is that tetrandrine affects multiple biological activities of cancer cells, including the inhibition of proliferation, angiogenesis, migration, and invasion; the induction of apoptosis and autophagy; the reversal of multidrug resistance (MDR); and the enhancement of radiation sensitization. This review focuses on introducing the latest information about the anti-tumor effects of tetrandrine on various cancers and its underlying mechanism. Moreover, we discuss the nanoparticle delivery system being developed for tetrandrine and the anti-tumor effects of other bisbenzylisoquinoline alkaloid derivatives on cancer cells. All current evidence demonstrates that tetrandrine is a promising candidate as a cancer chemotherapeutic.

Tetrandrine and cancer - An overview on the molecular approach

Tetrandrine has been known in the treatment of tuberculosis, hyperglycemia, negative ionotropic and chronotropic effects on myocardium, malaria, cancer and fever since years together. It has been known that, tetrandrine could modulate multiple signaling molecules such as kinases of cell cycle and rat sarcoma (RAS) pathway along with proteins of tumor suppressor genes, autophagy related, β-catenins, caspases, and death receptors. Moreover, tetrandrine exhibited reversal of drug resistance by modulating P-glyco protein (P-gp) expression levels in different cancers which is an added advantage of this compound compared to other chemotherapy drugs. Though, bioavailability of tetrandrine is a limiting factor, the anticancer activity was observed in animal models without changing any pharmacokinetic parameters. In the present review, role of tetrandrine as kinase inhibitor, inducer of autophagy and caspase pathways and suppressor of RAS mediated cell proliferation were discussed along with inhibition of angiogenesis. It has also been discussed that how tetrandrine potentiate anticancer effect in different types of cancers by modulating multidrug resistance under in vitro and in vivo trials including the available literature on the clinical trials.

Effects of agmatine on chlorpromazine toxicity in the liver of Wistar rats: the possible role of oxidant/antioxidant imbalance

Chlorpromazine (CPZ) is a member of a widely used class of antipsychotic agents. The metabolic pathways of CPZ toxicity were examined by monitoring oxidative/nitrosative stress markers. The aim of the study was to investigate the hypothesis that agmatine (AGM) prevents oxidative stress in the liver of Wistar rats 48 h after administration of CPZ. All tested compounds were administered intraperitoneally (i.p.) in one single dose. The animals were divided into control (C, 0.9% saline solution), CPZ (CPZ, 38.7 mg/kg b.w.), CPZ+AGM (AGM, 75 mg/kg b.w. immediately after CPZ, 38.7 mg/kg b.w. i.p.), and AGM (AGM, 75 mg/kg b.w.) groups. Rats were sacrificed by decapitation 48 h after treatment. The CPZ and CPZ+AGM treatments significantly increased thiobarbituric acid reactive substances (TBARS), the nitrite and nitrate (NO₂+NO₃) concentration, and superoxide anion (O₂^•-) production in rat liver homogenates compared with C values. CPZ injection decreased the capacity of the antioxidant defense system: superoxide dismutase (SOD) activity, catalase (CAT) activity, total glutathione (GSH) content, glutathione peroxidase (GPx) activity, and glutathione reductase (GR) activity compared with the values of the C group. However, treatment with AGM increased antioxidant capacity in the rat liver; it increased the CAT activity, GSH concentration, GPx activity, and GR activity compared with the values of the CPZ rats. Immunohistochemical staining of ED1 in rats showed an increase in the number of positive cells 48 h after acute CPZ administration compared with the C group. Our results showed that AGM has no protective effects on parameters of oxidative and/or nitrosative stress in the liver but that it absolutely protective effects on the antioxidant defense system and restores the antioxidant capacity in liver tissue after administration of CPZ.

Treatment with geraniol ameliorates methionine-choline-deficient diet-induced non-alcoholic steatohepatitis in rats

BACKGROUND AND AIM

Non-alcoholic steatohepatitis (NASH) is one of the most common causes of chronic liver disease and is considered to be a causative factor of cryptogenic cirrhosis and hepatocellular carcinoma. The aim of this work was to investigate whether treatment with geraniol (a monoterpene) attenuated NASH induced by methionine-choline-deficient (MCD) diet in rats.

METHODS

Rats were fed with MCD diet to induce NASH and treated with geraniol (200 mg/kg/day) for 10 weeks.

RESULTS

Treatment with geraniol reduced histological scores, fibrosis, and apoptosis in livers, lowered activities of alanine aminotransferase and aspartate aminotransferase in serum, and attenuated hepatic fat accumulation in rats fed with MCD diet. Treatment with geraniol preserved hepatic mitochondrial function, evidenced by reduced mitochondrial reactive oxygen species formation, enhanced adenosine triphosphate formation and membrane integrity, restored mitochondrial electron transport chain enzyme activity, and increased mitochondrial DNA content in rats fed with MCD diet. Treatment with geraniol reduced uncoupling protein 2 protein expression, and enhanced protein expression of prohibitin, mRNA expression of peroxisome proliferator-activated receptor α, and activity of mitochondrial carnitine palmitoyl transferase-I in livers of rats fed with MCD diet. Treatment with geraniol abated oxidative stress, evidenced by reduced malondialdehyde and 3-nitrotyrosine formation, enhanced activity of glutathione S-epoxide transferase, and down-regulated expression of inducible nitric oxide synthase and cytochrome P450 2E1 in livers of rats fed with MCD diet. Treatment with geraniol reduced myeloperoxidase activity and protein expression of tumor necrosis factor alpha and IL-6 in livers of rats fed with MCD diet.

CONCLUSION

Treatment with geraniol attenuated MCD-induced NASH in rats.

Chronic administration of caderofloxacin, a new fluoroquinolone, increases hepatic CYP2E1 expression and activity in rats

AIM

Caderofloxacin is a new fluoroquinolone that is under phase III clinical trials in China. Here we examined the effects of caderofloxacin on rat hepatic cytochrome P450 (CYP450) isoforms as well as the potential of caderofloxacin interacting with co-administered drugs.

METHODS

Male rats were treated with caderofloxacin (9 mg/kg, ig) once or twice daily for 14 consecutive days. The effects of caderofloxacin on CYP3A, 2D6, 2C19, 1A2, 2E1 and 2C9 were evaluated using a "cocktail" of 6 probes (midazolam, dextromethorphan, omeprazole, theophylline, chlorzoxazone and diclofenac) injected on d 0 (prior to caderofloxacin exposure) and d 15 (after caderofloxacin exposure). Hepatic microsomes from the caderofloxacin-treated rats were used to assess CYP2E1 activity and chlorzoxazone metabolism. The expression of CYP2E1 mRNA and protein in hepatic microsomes was analyzed with RT-PCR and Western blotting, respectively.

RESULTS

Fourteen-day administration of caderofloxacin significantly increased the activity of hepatic CYP2E1, leading to enhanced metabolism of chlorzoxazone. In vitro microsomal study confirmed that CYP2E1 was a major metabolic enzyme involved in chlorzoxazone metabolism, and the 14-d administration of caderofloxacin significantly increased the activity of CYP2E1 in hepatic microsomes, resulting in increased formation of 6-hydroxychlorzoxazone. Furthermore, the 14-d administration of caderofloxacin significantly increased the expression of CYP2E1 mRNA and protein in liver microsomes, which was consistent with the pharmacokinetic results.

CONCLUSION

Fourteen-day administration of caderofloxacin can induce the expression and activity of hepatic CYP2E1 in rats. When caderofloxacin is administered, a potential drug-drug interaction mediated by CYP2E1 induction should be considered.

Protective Effects of Agmatine against Chlorpromazine- Induced Toxicity in the Liver of Wistar Rats

The metabolic pathways of chlorpromazine (CPZ) toxicity were tracked by assessing oxidative/nitrosative stress markers. The main objective of the study was to test the hypothesis that agmatine (AGM) prevents oxidative/nitrosative stress in the liver of Wistar rats 15 days after administration of CPZ. All tested substances were administered intraperitoneally (i.p.) for 15 consecutive days. The rats were divided into four groups: the control group (C, 0.9 % saline solution), the CPZ group (CPZ, 38.7 mg/kg b.w.), the CPZ+AGM group (AGM, 75 mg/kg b.w. immediately after CPZ, 38.7 mg/kg b.w. i.p.) and the AGM group (AGM, 75 mg/kg b.w.).

Rats were decapitated 15 days after the appropriate treatment. In the CPZ group, CPZ concentration was significantly increased compared to C values (p<0.01), while AGM treatment induced the significant decrease in CPZ concentration in the CPZ+AGM group (p<0.05) and the AGM group (p<0.01). CPZ application to healthy rats did not lead to any changes of lipid peroxidation in the liver compared to the C group, but AGM treatment decreased that parameter compared to the CPZ group (p<0.05). In CPZ liver homogenates, nitrite and nitrate concentrations were increased compared to controls (p<0.001), and AGM treatment diminished that parameter in the CPZ group (p<0.05), as well as in the AGM group (p<0.001). In CPZ animals, glutathione level and catalase activity were decreased in comparison with C values (p<0.01 respectively), but AGM treatment increased the activity of catalase in comparison with CPZ animals (p<0.05 respectively). Western blot analysis supported biochemical findings in all groups. Our results showed that treatment with AGM significantly supressed the oxidative/nitrosative stress parameters and restored antioxidant defense in rat liver.

Dexamethasone altered steroidogenesis and changed redox status of granulosa cells

Glucocorticoids have been widely used in clinical application for anti-inflammatory and immunosuppressive function. Previous study reported that glucocorticoids adversely affect the reproductive system and can directly act on ovary. Here, we found that progesterone production induced by dexamethasone requiring activation of caspase-3 which may mediate differentiation and apoptosis of granulosa cells. Further study displayed that cellular glutathione level was increased and reactive oxygen species was decreased accompanied with unchanged mitochondrial membrane potential which may contribute to the maintenance of steroidogenesis in granulosa cells treated with dexamethasone. Dexamethasone also augmented the level of anti-Müllerian hormone secreted by preovulatory granulosa cells which indicated that dexamethasone may promote preantral follicles development.

Timosaponin A3 induces hepatotoxicity in rats through inducing oxidative stress and down-regulating bile acid transporters

Aim:

To investigate the mechanisms underlying the hepatotoxicity of timosaponin A3 (TA3), a steroidal saponin from Anemarrhena asphodeloides, in rats.

Methods:

Male SD rats were administered TA3 (100 mg·kg⁻¹·d⁻¹, po) for 14 d, and the blood and bile samples were collected after the final administration. The viability of a sandwich configuration of cultured rat hepatocytes (SCRHs) was assessed using WST-1. Accumulation and biliary excretion index (BEI) of d8-TCA in SCRHs were determined with LC-MS/MS. RT-PCR and Western blot were used to analyze the expression of relevant genes and proteins. ROS and ATP levels, and mitochondrial membrane potential (MMP) were measured. F-actin cytoskeletal integrity was assessed under confocal microscopy.

Results:

TA3 administration in rats significantly elevated the total bile acid in serum, and decreased bile acid (BA) component concentrations in bile. TA3 inhibited the viability of the SCRHs with an IC₅₀ value of 15.21±1.73 μmol/L. Treatment of the SCRHs with TA3 (1–10 μmol/L) for 2 and 24 h dose-dependently decreased the accumulation and BEI of d8-TCA. The TA3 treatment dose-dependently decreased the expression of BA transporters Ntcp, Bsep and Mrp2, and BA biosynthesis related Cyp7a1 in hepatocytes. Furthermore, the TA3 treatment dose-dependently increased ROS generation and HO-1 expression, decreased the ATP level and MMP, and disrupted F-actin in the SCRHs. NAC (5 mmol/L) significantly ameliorated TA3-induced effects in the SCRHs, whereas mangiferin (10–200 μg/mL) almost blocked TA3-induced ROS generation.

Conclusion:

TA3 triggers liver injury through inducing ROS generation and suppressing the expression of BA transporters. Mangiferin, an active component in Anemarrhena, may protect hepatocytes from TA3-induced hepatotoxicity.