The Journal of Toxicological Sciences
Online ISSN : 1880-3989
Print ISSN : 0388-1350
ISSN-L : 0388-1350
Volume 45, Issue 2
Displaying 1-5 of 5 articles from this issue
Original Article
  • Dongyi Fan, Simin Yang, Yuxiang Han, Ru Zhang, Lukun Yang
    2020 Volume 45 Issue 2 Pages 69-76
    Published: 2020
    Released on J-STAGE: February 15, 2020
    JOURNAL FREE ACCESS FULL-TEXT HTML

    MicroRNAs (miRNAs) are widely known as critical regulators in isoflurane-induced neurotoxicity during the development of brain. Moreover, isoflurane could aggravate cognitive impairment in diabetic rats. The present study was designed to investigate the role and mechanism of miR-140-5p on isoflurane-induced neurotoxicity in diabetic rats. Firstly, a diabetic rat model was established by injection of streptozotocin (STZ) and identified by Morris water maze test. The result indicated that isoflurane treatment exacerbated STZ-induced cognitive impairment, as demonstrated by increase of the latency to the platform and decrease of the proportion of time spent in the target quadrant. Secondly, miR-140-5p was up-regulated in diabetic rats treated with isoflurane. Functional assays revealed that knockdown of miR-140-5p attenuated neurotoxicity in diabetic rats, which was shown by a decrease of the latency to the platform and an increase of the proportion of time spent in the target quadrant. Mechanistically, we demonstrated that miR-140-5p directly bonded to SNX12 (sorting nexin 12). At last, the neuroprotective effect of miR-140-5p knockdown against isoflurane-aggravated neurotoxicity in diabetic rats was dependent on up-regulation of SNX12 and inhibition of cell apoptosis. In summary, these meaningful results demonstrated the mitigation of miR-140-5p knockdown against isoflurane-aggravated neurotoxicity in diabetic rats via SNX12, suggesting a novel target for neuroprotection in diabetes under isoflurane treatment.

Original Article
  • Chenghui Leng, Junli Sun, Keke Xin, Jianlin Ge, Ping Liu, Xiaojing Fen ...
    2020 Volume 45 Issue 2 Pages 77-86
    Published: 2020
    Released on J-STAGE: February 15, 2020
    JOURNAL FREE ACCESS FULL-TEXT HTML

    Sepsis-induced acute lung injury (ALI) has high morbidity and mortality rates, and there remains a need for therapeutic methods to improve the outcome of ALI patients. miR-483-5p is an important regulator for the development of various diseases such as sepsis. Nevertheless, it is not known whether miR-483-5p has an effect on sepsis-induced ALI. To explore this issue, this study used cecal ligation and puncture (CLP)-treated mice and lipopolysaccharide (LPS)-treated pulmonary microvascular endothelial cells (PMVECs) cells to simulate the models of sepsis-induced ALI in vivo and in vitro. Pathological and histological changes of lungs from sepsis-induced ALI mice were detected by Hematoxylin-eosin staining. The detection levels of caspase-3, interleukin (IL)-6 and IL-1β were used to reflect the effect of miR-483-5p on apoptosis and inflammation of sepsis-induced ALI. The detection level of lactate dehydrogenase (LDH) in PMVECs cells was used to reflect the severe extent of sepsis-induced injury. The expression of miR-483-5p in lung tissues of sepsis-induced ALI mice was determined by qRT-PCR. In addition, the interaction of miR-483-5p with PIAS1 was identified and validated by Targetscan website and luciferase reporter assay, respectively. The results showed that miR-483-5p was up-regulated in the lung tissues of sepsis-induced ALI mice. Knockdown of miR-483-5p effectively ameliorated lung injury in mice with sepsis-induced ALI and inhibited inflammation and apoptosis of LPS-treated PMVECs cells. Furthermore, in vitro experiment revealed that PIAS1 was a potential target of miR-483-5p. Moreover, miR-483-5p could suppress PIAS1 expression to aggravate inflammation and apoptosis of LPS-treated PMVECs cells. These findings suggest miR-483-5p is a potential therapeutic and diagnostic biomarker for sepsis-induced ALI and provide a new insight for understanding the molecular mechanism of sepsis-induced ALI.

Letter
  • Masaaki Miyata, Akihiro Funaki, Chiaki Fukuhara, Yukino Sumiya, Yoshim ...
    2020 Volume 45 Issue 2 Pages 87-94
    Published: 2020
    Released on J-STAGE: February 15, 2020
    JOURNAL FREE ACCESS FULL-TEXT HTML

    Mice lacking the farnesoid X receptor (FXR) are used as a genetic model for nonalcoholic fatty liver disease because their livers exhibit hepatic steatosis and inflammation. The influence of taurine drinking on disrupted hepatic function was investigated using female Fxr-null mice. Significant decreases in the levels of hepatic damage-associated diagnostic markers, hepatic triglycerides, non-esterified fatty acids, and total bile acids were found in Fxr-null mice that had drunk water containing 0.5% taurine for four weeks. Hepatic but not serum taurine concentrations were significantly increased in these mice. The expression levels of oxidative stress-related genes (Hmox1 and Gsta1) and fatty acid synthetic genes (Acc1 and Scd1) were significantly decreased in these mice. These results suggest that drinking taurine improves hepatic steatosis and dysfunction caused by a lack of FXR.

Original Article
  • Tomoka Hisaki, Maki Aiba née Kaneko, Morihiko Hirota, Masato Matsuoka, ...
    2020 Volume 45 Issue 2 Pages 95-108
    Published: 2020
    Released on J-STAGE: February 15, 2020
    JOURNAL FREE ACCESS FULL-TEXT HTML

    We present a systematic, comprehensive and reproducible weight-of-evidence approach for predicting the no-observed-adverse-effect level (NOAEL) for systemic toxicity by using read-across and quantitative structure-activity relationship (QSAR) models to fill gaps in rat repeated-dose and developmental toxicity data. As a case study, we chose valproic acid, a developmental toxicant in humans and animals. High-quality in vivo oral rat repeated-dose and developmental toxicity data were available for five and nine analogues, respectively, and showed qualitative consistency, especially for developmental toxicity. Similarity between the target and analogues is readily defined computationally, and data uncertainties associated with the similarities in structural, physico-chemical and toxicological properties, including toxicophores, were low. Uncertainty associated with metabolic similarity is low-to-moderate, largely because the approach was limited to in silico prediction to enable systematic and objective data collection. Uncertainty associated with completeness of read-across was reduced by including in vitro and in silico metabolic data and expanding the experimental animal database. Taking the “worst-case” approach, the smallest NOAEL values among the analogs (i.e., 200 and 100 mg/kg/day for repeated-dose and developmental toxicity, respectively) were read-across to valproic acid. Our previous QSAR models predict repeated-dose NOAEL of 148 (males) and 228 (females) mg/kg/day, and developmental toxicity NOAEL of 390 mg/kg/day for valproic acid. Based on read-across and QSAR, the conservatively predicted NOAEL is 148 mg/kg/day for repeated-dose toxicity, and 100 mg/kg/day for developmental toxicity. Experimental values are 341 mg/kg/day and 100 mg/kg/day, respectively. The present approach appears promising for quantitative and qualitative in silico systemic toxicity prediction of untested chemicals.

Letter
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