Induction of CYP1A1 increases gefitinib-induced oxidative stress and apoptosis in A549 cells

Development of a Normal Porcine Cell Line Growing in a Heme-Supplemented, Serum-Free Condition for Cultured Meat

A key element for the cost-effective development of cultured meat is a cell line culturable in serum-free conditions to reduce production costs. Heme supplementation in cultured meat mimics the original meat flavor and color. This study introduced a bacterial extract generated from Corynebacterium that was selected for high-heme expression by directed evolution. A normal porcine cell line, PK15, was used to apply the bacterial heme extract as a supplement. Consistent with prior research, we observed the cytotoxicity of PK15 to the heme extract at 10 mM or higher. However, after long-term exposure, PK15 adapted to tolerate up to 40 mM of heme. An RNA-seq analysis of these heme-adapted PK15 cells (PK15H) revealed a set of altered genes, mainly involved in cell proliferation, metabolism, and inflammation. We found that cytochrome P450, family 1, subfamily A, polypeptide 1 (CYP1A1), lactoperoxidase (LPO), and glutathione peroxidase 5 (GPX5) were upregulated in the PK15H heme dose dependently. When we reduced serum serially from 2% to serum free, we derived the PK15H subpopulation that was transiently maintained with 5-10 mM heme extract. Altogether, our study reports a porcine cell culturable in high-heme media that can be maintained in serum-free conditions and proposes a marker gene that plays a critical role in this adaptation process.

CYP1A inhibitors: Recent progress, current challenges, and future perspectives

Mammalian cytochrome P450 1A (CYP1A) are key phase I xenobiotic-metabolizing enzymes that play a distinctive role in metabolic activation or metabolic clearance of a variety of procarcinogens, drugs, and endogenous substances. Human CYP1A subfamily contains two members (hCYP1A1 and hCYP1A2), which are known to catalyze the oxidative activation of some environmental procarcinogens into carcinogenic species. Increasing evidence has demonstrated that CYP1A inhibitor therapies are promising strategies for cancer chemoprevention or overcoming CYP1A-associated drug toxicity and resistance. Herein, we reviewed recent advances in the discovery and characterization of hCYP1A inhibitors, from the discovery approaches to structural features and biomedical applications of hCYP1A inhibitors. The inhibition potentials, inhibition modes, and inhibition constants of all reported hCYP1A inhibitors are comprehensively summarized. Meanwhile, the structural features and structure-activity relationships of different classes of hCYP1A1 and hCYP1A2 inhibitors are analyzed and discussed in depth. Furthermore, the major challenges and future directions for this field are presented and highlighted. Collectively, the information and knowledge presented here will strongly facilitate the researchers to discover and develop more efficacious CYP1A inhibitors for specific purposes, such as chemo-preventive agents or as tool molecules in hCYP1A-related fundamental studies.

A novel 3D bio-printing “liver lobule” microtissue biosensor for the detection of AFB1

In this paper, a novel "liver lobule" microtissue biosensor based on 3D bio-printing is developed to rapidly determine aflatoxin B₁ (AFB₁). Methylacylated Hyaluronic acid (HAMA) hydrogel, HepG2 cells, and carbon nanotubes are used to construct "liver lobule" models. In addition, 3D bio-printing is used to perform high-throughput and standardized preparation in order to simulate the organ morphology and induce functional formation. Afterwards, based on the electrochemical rapid detection technology, a 3D bio-printed "liver lobule" microtissue is immobilized on the screen-printed electrode, and the mycotoxin is detected by differential pulse voltammetry (DPV). The DPV response increases with the concentration of AFB₁ in the range of 0.1-3.5 μg/mL. The linear detection range is 0.1-1.5 μg/mL and the calculated lowest detection limit is 0.039 μg/mL. Thus, this study develops a new mycotoxin detection method based on the 3D printing technology, which has high stability and reproducibility. It has wide application prospects in the field of detection and evaluation of food hazards.

A Cell-Based Platform for the Investigation of Immunoproteasome Subunit β5i Expression and Biology of β5i-Containing Proteasomes

The degradation of most intracellular proteins is a dynamic and tightly regulated process performed by proteasomes. To date, different forms of proteasomes have been identified. Currently the role of non-constitutive proteasomes (immunoproteasomes (iPs) and intermediate proteasomes (intPs)) has attracted special attention. Here, using a CRISPR-Cas9 nickase technology, four cell lines: histiocytic lymphoma, colorectal adenocarcinoma, cervix adenocarcinoma, and hepatocarcinoma were modified to express proteasomes with mCherry-tagged β5i subunit, which is a catalytic subunit of iPs and intPs. Importantly, the expression of the chimeric gene in modified cells is under the control of endogenous regulatory mechanisms and is increased following IFN-γ and/or TNF-α stimulation. Fluorescent proteasomes retain catalytic activity and are distributed within the nucleus and cytoplasm. RNAseq reveals marginal differences in gene expression profiles between the modified and wild-type cell lines. Predominant metabolic pathways and patterns of expressed receptors were identified for each cell line. Using established cell lines, we demonstrated that anti-cancer drugs Ruxolitinib, Vincristine and Gefitinib stimulated the expression of β5i-containing proteasomes, which might affect disease prognosis. Taken together, obtained cell lines can be used as a platform for real-time studies of immunoproteasome gene expression, localization of iPs and intPs, interaction of non-constitutive proteasomes with other proteins, proteasome trafficking and many other aspects of proteasome biology in living cells. Moreover, the established platform might be especially useful for fast and large-scale experiments intended to evaluate the effects of different conditions including treatment with various drugs and compounds on the proteasome pool.

Differences in susceptibility of HT-29 and A549 cells to statin-induced toxicity: An investigation using high content screening

Statins are a group of hydroxymethylglutaryl coenzyme A reductase inhibitors that are used in the treatment of cardiovascular diseases. However, statins have been found to be cytotoxic, and many unexpected side effects have been reported in clinical applications. The susceptibilities of different cell lines toward statins are diverse, and the mechanisms of cytotoxicity remain unknown. Therefore, the present study aimed to investigate differences in the susceptibility to and mechanisms of statin-induced cytotoxicity in two cell lines, HT-29 and A549, using a high content screening-based multiparametric toxicity assay panel. We found that the two cell types exhibited differing susceptibilities to the cytotoxic effects of the different statins. Additionally, the cytotoxicity was inconsistent between different statins in the two cell lines. Four statins with strong cytotoxicity decreased the viability of HT-29 cells via the mitochondrial pathway, as evidenced by decreased mitochondrial membrane potential, and elevated mitochondrial mass, calcium release and cell apoptosis, and reactive oxygen species. In contrast, these four statins only induced a decrease in the mitochondrial membrane potential in A549 cells. The above results provide an objective reason for future evaluations of cytotoxic differences in cell types and the underlying mechanisms of cytotoxicity in different statins, and provide a good scientific basis for further research on countermeasures against statin-induced cell injuries.

Cigarette smoke extract stimulates bronchial epithelial cells to undergo a SUMOylation turnover

BACKGROUND

Chronic obstructive pulmonary disease (COPD) characterized by the airway and lung inflammation, is a leading cause of morbidity and mortality worldwide, especially among smokers over 40 years of age and individuals exposed to biomass smoke. Although the detailed mechanisms of this disease remain elusive, there is feasible evidence that protein posttranslational modifications (PTMs) may play a role in its pathoetiology. We thus conducted studies to dissect the effect of cigarette smoke extracts (CSE) on the change of SUMOylated substrates in human bronchial epithelial cells (HBEs).

METHODS

Samples were collected in HBEs with or without 24 h of CSE insult and then subjected to Western-blot and LC-MS/MS analysis. Subsequently, bioinformatic tools were used to analyze the data. The effect of SUMOylation on cytochrome P450 1A1 (CYP1A1) was evaluated by flow cytometry.

RESULTS

It was noted that CSE stimulated HBEs to undergo a SUMOylation turnover as evidenced by the changes of SUMOylated substrates and SUMOylation levels for a particular substrate. The SUMOylated proteins are relevant to the regulation of biological processes, molecular function and cellular components. Particularly, CSE stimulated a significant increase of SUMOylated CYP1A1, a critical enzyme involved in the induction of oxidative stress.

CONCLUSIONS

Our data provide a protein SUMOylation profile for better understanding of the mechanisms underlying COPD and support that smoking induces oxidative stress in HBEs, which may predispose to the development of COPD in clinical settings.

Exacerbation of gefitinib-induced liver injury by glutathione reduction in mice

Gefitinib (GEF) is the first selective tyrosine kinase inhibitor of epidermal growth factor receptor. It is associated with the occurrence of clinical drug-induced liver injury. Although GEF is metabolized to chemically reactive metabolites by cytochrome P450 3A and 1A enzymes and then conjugated to glutathione (GSH), whether these reactive metabolites contribute to GEF-induced toxicity remains unknown. In this study, we investigated whether GSH depletion can sensitize mice to liver injury caused by GEF. Male C57BL/6J mice were intraperitoneally pretreated with L-buthionine (S,R)-sulfoximine (BSO) at 700 mg/kg to inhibit GSH synthesis and then orally administered GEF at 500 mg/kg every 24 hr for 4 consecutive days. The coadministration of BSO and GEF increased plasma alanine aminotransferase (ALT) levels to approximately 700 U/L and 1600 U/L at 72 and 96 hr after the first administration, respectively, whereas the increase in plasma ALT levels in mice receiving GEF at 500 mg/kg alone was limited, suggesting that GSH plays a protective role in GEF-induced liver injury. Histological examination showed nuclear karyorrhexis and sporadic single hepatocyte death in the livers of BSO+GEF coadministered mice. In these mice, the hepatic expression levels of heme oxygenase 1 (Hmox1) and metallothionein 2 (Mt2) mRNA, caspase 3/7 enzymatic activity, and the amounts of 2-thiobarbiuric acid reactive substances were significantly increased, suggesting the presence of oxidative stress, which may be associated with hepatocellular death. Together, these results show that oxidative stress as well as the reactive metabolites of GEF are involved in GEF-induced liver injury in GSH-depleted mice.

Hybrid Compounds & Oxidative Stress Induced Apoptosis in Cancer Therapy

Elevated Reactive Oxygen Species (ROS) generated by the conventional cancer therapies and the endogenous production of ROS have been observed in various types of cancers. In contrast to the harmful effects of oxidative stress in different pathologies other than cancer, ROS can speed anti-tumorigenic signaling and cause apoptosis of tumor cells via oxidative stress as demonstrated in several studies. The primary actions of antioxidants in cells are to provide a redox balance between reduction-oxidation reactions. Antioxidants in tumor cells can scavenge excess ROS, causing resistance to ROS induced apoptosis. Various chemotherapeutic drugs, in their clinical use, have evoked drug resistance and serious side effects. Consequently, drugs having single-targets are not able to provide an effective cancer therapy. Recently, developed hybrid anticancer drugs promise great therapeutic advantages due to their capacity to overcome the limitations encountered with conventional chemotherapeutic agents. Hybrid compounds have advantages in comparison to the single cancer drugs which have usually low solubility, adverse side effects, and drug resistance. This review addresses two important treatments strategies in cancer therapy: oxidative stress induced apoptosis and hybrid anticancer drugs.

Structural, functional, and molecular impact on the cardiovascular system in ApoE-/- mice exposed to aerosol from candidate modified risk tobacco products, Carbon Heated Tobacco Product 1.2 and Tobacco Heating System 2.2, compared with cigarette smoke

AIM

To investigate the molecular, structural, and functional impact of aerosols from candidate modified risk tobacco products (cMRTP), the Carbon Heated Tobacco Product (CHTP) 1.2 and Tobacco Heating System (THS) 2.2, compared with that of mainstream cigarette smoke (CS) on the cardiovascular system of ApoE-/- mice.

METHODS

Female ApoE-/- mice were exposed to aerosols from THS 2.2 and CHTP 1.2 or to CS from the 3R4F reference cigarette for up to 6 months at matching nicotine concentrations. A Cessation and a Switching group (3 months exposure to 3R4F CS followed by filtered air or CHTP 1.2 for 3 months) were included. Cardiovascular effects were investigated by echocardiographic, histopathological, immunohistochemical, and transcriptomics analyses.

RESULTS

Continuous exposure to cMRTP aerosols did not affect atherosclerosis progression, heart function, left ventricular (LV) structure, or the cardiovascular transcriptome. Exposure to 3R4F CS triggered atherosclerosis progression, reduced systolic ejection fraction and fractional shortening, caused heart LV hypertrophy, and initiated significant dysregulation in the transcriptomes of the heart ventricle and thoracic aorta. Importantly, the structural, functional, and molecular changes caused by 3R4F CS were improved in the smoking cessation and switching groups.

CONCLUSION

Exposure to cMRTP aerosols lacked most of the CS exposure-related functional, structural, and molecular effects. Smoking cessation or switching to CHTP 1.2 aerosol caused similar recovery from the 3R4F CS effects in the ApoE-/- model, with no further acceleration of plaque progression beyond the aging-related rate.

Bisphenol A affects estradiol metabolism by targeting CYP1A1 and CYP19A1 in human placental JEG-3 cells

Estradiol, in some way or another, plays a critically important physiologic role in the establishment and maintenance of pregnancy. This study was designed to investigate whether BPA affects the estradiol level of human placental JEG-3 cells, which may contribute to insights into the reproductive toxicity and endocrine disruption of BPA. The JEG-3 cells were treated with increasing concentrations of BPA (0.1 to 50 μM). We observed that BPA significantly reduced estradiol level of JEG-3 cells in a dose-dependent manner, which was accompanied by an increase in CYP1A1 protein level and an inhibition of CYP19A1 protein level. Additionally, by lentiviral transduction, we determined that estradiol level of JEG-3 cells over-expressing CYP1A1 gene was notably decreased and the decrease was of 84.9% compared to the control. Meanwhile, estradiol was almost undetectable in CYP19A1 knockdown group. On the contrary, the group with over-expression of CYP19A1 gene increased estradiol level by 8.6 fold while the CYP1A1 knockdown group increased by 5.6 fold. In summary, our research clearly showed that BPA alters JEG-3 estradiol synthesis and catabolism due to its action on CYP1A1 and CYP19A1 protein levels and may interfere with the normal process of placenta formation and embryonic development during early pregnancy.

Interaction between phytotherapy and oral anticancer agents: prospective study and literature review

Cancer is becoming more prevalent in elderly patient. Due to polypharmacy, older adults with cancer are predisposed to drug-drug interactions. There is also an increasing interest in the use of complementary and alternative medicine (CAM). Thirty to seventy percent of patients with cancer have used CAM. Through pharmaceutical counseling sessions, we can provide advices on herb-drug interactions (HDI). All the patients seen in pharmaceutical counseling sessions were prospectively included. Information was collected during these sessions: prescribed medication (oral anticancer agents (OAA) and other drugs), CAM (phytotherapy especially), and use of over-the-counter (OTC) drugs. If pharmacist considered an interaction or an intervention clinically relevant, the oncologist was notified. Then, a literature review was realized to identify the potential HDI (no interactions, precautions for use, contraindication). Among 201 pharmacist counseling sessions, it resulted in 104 interventions related to 46 HDI, 28 drug-drug interactions and 30 others (wrong dosage, omission…). To determine HDI, we review 73 medicinal plants which are used by our patients with cancer and 31 OAA. A total of 1829 recommendations were formulated about 59 (75%) medical plants and their interaction with an OAA. Herb-drug interactions should not be ignored by healthcare providers in their management of cancer patients in daily practice.

Inhibition of PLA2G4A Reduces the Expression of Lung Cancer-Related Cytokines

Phospholipase A2-IVA (PLA2G4A) is the most abundant subtype of cytoplasmic phospholipase A2 (cPLA2) and is an important enzyme in tumor development. Our study aimed to explore the role of PLA2G4A in the regulation of lung cancer. The contents of cell-related cytokines (microsomal prostaglandin E synthase-1 [mPGES], PGE2, and prostacyclin [PGI2]) in A549 cells were analyzed by ELISA kits. Cell counting kit-8 (CCK8) was used to detect the effects of inhibitor of cPLA2 (arachidonyl trifluoromethyl ketone [AACOCF3]) on the proliferation of A549 cells. The migration and invasion of A549 cells were tested by cell scratch wound healing assay and transwell assay, respectively. Real-time quantitative PCR and Western blotting were used to detect the effect of inhibitor AACOCF3 on the expression of related mRNA and protein in A549 cells. ELISA result showed that the levels of mPGES, PGE2, and PGI2 in control group were significantly higher than those in the AACOCF3 group. Cell inhibition rate in the control group was significantly lower than that in the AACOCF3 group. The percentage of wound healing in the control group was significantly higher than that in the AACOCF3 group. Meanwhile, the relative invasive number of cells in the control group was significantly higher than those in the AACOCF3 group. The expression levels of related mRNA of PLA2G4A and cyclooxygenase-2 (COX-2) and the expression levels of mPGES, COX-1, and COX-2 protein in the control group were significantly higher than those in the AACOCF3 group. Our research showed that PLA2G4A was involved in migration and invasion of lung cancer cells.