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Transition metals refer to the elements in the d and ds blocks of the periodic table. Since the success of cisplatin and auranofin, transition metal‐based compounds have become a prospective source for drug development, particularly in cancer treatment. In recent years, extensive studies have shown that numerous transition metal‐based compounds could modulate autophagy, promising a new therapeutic strategy for metal‐related diseases and the design of metal‐based agents. Copper, zinc, and manganese, which are common components in physiological pathways, play important roles in the progression of cancer, neurodegenerative diseases, and cardiovascular diseases. Furthermore, enrichment of copper, zinc, or manganese can regulate autophagy. Thus, we summarized the current advances in elucidating the mechanisms of some metals/metal‐based compounds and their functions in autophagy regulation, which is conducive to explore the intricate roles of autophagy and exploit novel therapeutic drugs for human diseases. [ABSTRACT FROM AUTHOR]

The utility and sensitivity of the newly developed flow cytometric Pig‐a gene mutation assay have become a great concern recently. In this study, we have examined the feasibility of integrating the Pig‐a assay as well as micronucleus and Comet endpoints into acute and subchronic general toxicology studies. Male Sprague–Dawley rats were treated for 3 or 28 consecutive days by oral gavage with procarbazine hydrochloride (PCZ) or ethyl carbamate (EC) up to the maximum tolerated dose. The induction of CD59‐negative reticulocytes and erythrocytes, micronucleated reticulocytes in peripheral blood, micronucleated polychromatic erythrocytes in bone marrow, and Comet responses in peripheral blood, liver, kidney, and lung were evaluated at one, two, or more timepoints. Both PCZ and EC produced positive responses at most analyzed timepoints in all tissue types, both with the 3‐day and 28‐day treatment regimens. Furthermore, comparison of the magnitude of the genotoxicity responses indicated that the micronucleus and Comet endpoints generally produced greater responses with the higher dose, short‐term treatments in the 3‐day study, while the Pig‐a assay responded better to the cumulative effects of the lower dose, but repeated subchronic dosing in the 28‐day study. Collectively, these results indicate that integration of several in vivo genotoxicity endpoints into a single routine toxicology study is feasible and that the Pig‐a assay may be particularly suitable for integration into subchronic dose studies based on its ability to accumulate the mutations that result from repeated treatments. This characteristic may be especially important for assaying lower doses of relatively weak genotoxicants. Environ. Mol. Mutagen. 60:56–71, 2019. © 2018 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Myelosuppression is one of the serious side effects of anticancer chemotherapeutic drugs that deteriorate the bodily functions of patients, thereby affecting the quality of life considerably. Prevention of myelosuppression in anticancer chemotherapy is an important research topic. A stabilized chemotherapy-induced myelosuppression animal model is necessary in experimental research. This study aimed to establish an optimized animal model of chemotherapy-induced bone marrow suppression. After C57 BL/6 mice were treated with intermediate- and high-dose (25/50 mg/kg) cyclophosphamide ( CTX) for 10 days, the body-weight, changes in thymus and spleen, number of white blood cells ( WBCs), red blood cells ( RBCs), and platelets ( PLTs) and changes in bone marrow in the mice were systematically evaluated at the next 2, 7 and 14 days. Our results demonstrated that CTX treatments could significantly decrease the body-weight of mice, as well as the ratios of the weights of thymus and spleen to body-weight. The physiological structures of thymus and spleen were destroyed by CTX treatments. The number of WBCs and RBCs significantly declined after CTX treatments; however, the number of PLTs increased. Moreover, the expression of Sca1 in bone marrow cells decreased on Day 2 but increased on Day 14. The expression of CD34 decreased in bone marrow cells after CTX treatments. In conclusion, mice models, with high-dose CTX treatments for 10 days, can be an optimized animal model for chemotherapy-induced bone marrow suppression. [ABSTRACT FROM AUTHOR]

Activating transcription factor ( ATF) 4 is involved in the regulation of oxidative stress in fibroblasts and neurons. The role of ATF4 in hepatocytes, however, is unknown. The aim of this study was to investigate the role of ATF4 in hepatocytes in oxidative stress under a high-fat diet ( HFD). Here, we showed that palmitate-stimulated reactive oxygen species ( ROS) production and triglyceride ( TG) accumulation is blocked by ATF4 deficiency in primary hepatocytes. Consistently, HFD-induced oxidative stress, TG accumulation and expression of cytochrome P450, family 2, subfamily, polypeptide 1 ( CYP2E1) are also blocked by knocking down ATF4 expression in the mouse liver. This suggests that ATF4 might regulate oxidative stress via CYP2E1 under an HFD. In addition, we observed that expression of CYP2E1 is indirectly regulated by ATF4 in a cAMP-responsive element binding protein ( CREB)-dependent manner, which can directly activate the CYP2E1 promoter activity. Notably, ATF4-stimulated ROS production is inhibited in vivo by treatment with diallyl sulphide, a selective CYP2E1 inhibitor. Finally, we showed that ATF4 expression in the liver is responsible for the protective effects against HFD-induced CYP2E1 expression, oxidative stress, and TG accumulation. Taken together, these observations suggest that ATF4 is a novel regulator of oxidative stress as well as accumulation of TG in response to HFD. [ABSTRACT FROM AUTHOR]

Wuzhi tablet (WZ, registration no. in China: Z20025766) is a preparation of an ethanol herb extract of Wuweizi ( Schisandra sphenanthera) containing 7.5 mg Schisantherin A per tablet. It was reported recently that WZ could significantly increase the blood concentrations of tacrolimus, which might be due to the inhibitory effect of WZ and its ingredients on P-gp and/or CYP450 activity. Paclitaxel is a substrate of the efflux transporter P-gp, and is mainly metabolized by CYP450 enzymes in the liver. Therefore, the purpose of this study was to investigate whether and how WZ affects the pharmacokinetics of paclitaxel in rats. After pretreatment with WZ, there were significant increases in the AUC0-24h of oral paclitaxel (from 280.8 ± 97.3 to 543.5 ± 115.2 h ng/mL; p < 0.05) and Cmax (from 44.6 ± 16.4 to 86.8 ± 16.1 ng/mL; p < 0.05). The pharmacokinetic data for i.v. paclitaxel with WZ showed a relatively small (when compared against oral paclitaxel) but still significant increase in AUC0-24h (from 163.6 ± 22.1 to 212.7 ± 17.7 h ng/mL; p < 0.05) and a decrease in clearance (from 3.2 ± 0.6 to 2.2 ± 0.3 L/h/kg; p < 0.05). Thus, the presence of WZ improved the systemic exposure of paclitaxel in rats. The herb-drug interaction between WZ and paclitaxel should be taken into consideration in clinical use. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The major histocompatibility complex class I (MHCI) trafficking signal (MITD) plays a pivotal role in enhancing the efficacy of mRNA vaccines. However, there was a lack of research investigating its efficacy in enhancing immune responses to RNA virus infections. Here, we have developed an innovative strategy for the formulation of mRNA vaccines. This approach involved the integration of MITD into the mRNA sequence encoding the virus antigen. Mechanistically, MITD‐based mRNA vaccines can strengthen immune protection by mimicking the dynamic trafficking properties of MHCI molecule and thus expand the memory specific B and T cells. The model MITD‐based mRNA vaccines encoding binding receptor‐binding domain (RBD) of SARS‐CoV‐2 were indeed found to achieve protective duration, optimal storage stability, broad efficacy, and high safety. [ABSTRACT FROM AUTHOR]