[Corrigendum] Effects of simvastatin on iNOS and caspase­3 levels and oxidative stress following smoke inhalation injury.

After the publication of the above paper, the authors have noticed that the affiliations were presented incorrectly; essentially, Drs Rong­qiang Yang, Peng­fei Guo, Qing­nan Meng, Ya Gao, Imran Khan, Xiao­bo Wang and Zheng­jun Cui are based at the Department of Burn and Repair Reconstruction Surgery, The First Affiliated Hospital of Zhengzhou University, whereas Drs Zhao Ma and Cheng Chang are located at The School of Basic Medical Science of Zhengzhou University. Therefore, the affiliations for this paper should have appeared as follows: Rong­Qiang Yang1, Peng­Fei Guo1, Zhao Ma2, Cheng Chang2, Qing­Nan Meng1, Ya Gao1, Imran Khan1, Xiao­Bo Wang1 and Zheng­Jun Cui1. 1Department of Burn and Repair Reconstruction Surgery, The First Affiliated Hospital of Zhengzhou University; 2The School of Basic Medical Science of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China. The authors regret that these errors with the author affiliations were not noticed prior to the publication of their paper, and apologize for any inconvenience caused. [the original article was published in Molecular Medicine Reports 22: 3405-3417, 2020; DOI: 10.3892/mmr.2020.11413].

Effects of simvastatin on iNOS and caspase­3 levels and oxidative stress following smoke inhalation injury.

The overexpression of inducible nitric oxide synthase (iNOS) induces cell apoptosis through various signal transduction pathways and aggravates lung injury. Caspase­3 is an important protein in the apoptotic pathway and its activation can exacerbate apoptosis. Simvastatin, a hydroxymethyl glutaryl­A reductase inhibitor, protects against smoke inhalation injury by inhibiting the synthesis and release of inflammatory factors and decreasing cell apoptosis. Following the establishment of an animal model of smoke inhalation injury, lung tissue and serum were collected at different time points and the protein and mRNA expression of iNOS and caspase­3 in lung tissue by immunochemistry, western blot and reverse transcription­quantitative polymerase chain reaction, the malondialdehyde (MDA) content and superoxide dismutase (SOD) activity in lung tissue and serum were analyzed using thiobarbituric acid method and the WST­1 method. The results were statistically analyzed. The lung tissues of the rats in the saline group and the low­, middle­ and high­dose groups exhibited clear edema and hemorrhage, and had significantly higher pathological scores at the various time points compared with the rats in the control group (P<0.05). Furthermore, lung tissue and serum samples obtained from these four groups had significantly higher mRNA and protein expression levels of iNOS and caspase­3 (P<0.05), significantly lower SOD activity and higher MDA content (P<0.05). Compared with the saline group, the low­, middle­ and high­dose groups had significantly lower pathological scores (P<0.05), significantly lower mRNA and protein expression levels of iNOS, caspase­3 and MDA content in lung tissues (P<0.05) and significantly higher SOD activity in lung tissues and serum. The middle­ and high­dose groups had significantly lower pathological scores (P<0.05), significantly decreased iNOS and caspase­3 mRNA and protein expression in lung tissues, significantly higher SOD activity in lung tissues and serum and a significantly lower MDA content (P<0.05) compared with the low­dose group. With the exception of SOD activity in lung tissues at 24 and 72 h and MDA content in serum at 48 h, no significant differences were observed between the middle­ and high­dose groups. The present study demonstrated that there was an association between the therapeutic effect and dosage of simvastatin within a definitive range. In rats with smoke inhalation injury, simvastatin inhibited iNOS and caspase­3 expression in lung tissues and mitigated oxidative stress, thereby exerting a protective effect. In addition, the effect and dose were associated within a definitive range.

[Effects of composite resin and glass-ionomer cements on proliferation and functional activity of human macrophages].

PURPOSE: To study the effects of composite resin and glass-ionomer cements on cell proliferation and function of human macrophages in vitro. METHODS: Macrophages were differentiated from THP-1 cells after treatment with phorbol ester and used as the model of inflammatory cells, which were treated by specimens from glass-ionomer cements(GC), composite resin Filtek Z350 (3M) and Filtek P60(3M) on culture medium for 24 hours. The cell proliferation of the tooth-colored restorative materials on human macrophages in vitro was evaluated by MTT color imetric assay, and determined for IL-1 content in these material specimens by ELISA. All statistical analyses were performed using the SPSS 17.0 software package. RESULTS: Compared with control group, composite resin Filtek Z350(3M) and Filtek P60(3M) significantly enhanced the proliferation of human macrophages (P<0.05), while Glass-ionomer had little effect on the proliferation of human macrophages (P>0.05). Glass-ionomer could promote macrophages to secrete IL-1ß and the difference was statistically significant(P<0.05). The composite resin could not cause release of IL-1ß from macrophages (P>0.05). CONCLUSIONS: Composite resin enhances proliferation and function of human macrophages. The effect may be associated with hypersensitivity of dentin. Glass-ionomer cement has little effect on proliferation of macrophages, but may lead to progress of inflammation.

Development of the mesencephalic trigeminal nucleus requires a paired homeodomain transcription factor, Drg11.

The mesencephalic trigeminal nucleus (Me5) innervates muscle spindles and is responsible for receiving and transmitting proprioception from the oro-facial region. Molecular mechanisms underlying the development of the Me5 are poorly understood. Evidence is provided here that transcription factor Drg11 is required for Me5 development. Drg11 was expressed in the Me5 cells of the embryonic and early postnatal mouse brains, and the Me5 cells were absent in Drg11-/- mice at birth. The absence of the Me5 cells in Drg11-/- mice appeared to be caused by increased cell death in the Me5 during embryonic development. In postnatal Drg11-/- mice, Me5 cell innervation of masseter muscle spindles was undetectable, while robust trigeminal motoneuron innervation of masseter muscle fibers was detected. The postnatal body weight of Drg11-/- mice was notably less than that of wild-type mice, and this might result, in part, from disruption of the oro-facial proprioceptive afferent pathway. Taken together, our results demonstrate an essential role for Drg11 in the development of the Me5.

Lmx1b is essential for Fgf8 and Wnt1 expression in the isthmic organizer during tectum and cerebellum development in mice.

Secreted factors FGF8 and WNT1 are essential either for the inductive activity of the isthmus organizer or for the regionalization of the midbrain-hindbrain boundary (MHB). However, transcriptional regulation of these secreted factors during development remains to be elucidated. Here we show that the LIM homeobox gene Lmx1b is expressed in the anterior embryo as early as E7.5 and its expression becomes progressively restricted to the isthmus at E9.0. Analysis of gene expression in the MHB of the mutant embryos showed that many genes were lost by E9.5. In the MHB of Lmx1b-/- embryos, the expression of Fgf8, which normally occurs at the 4-somite stage, was completely absent, whereas Wnt1 was downregulated before the 4-somite stage. Moreover, transcription factors En1 and Pax2 were also downregulated prior to the 4-somite stage, whereas Gbx2 downregulation occurred at the 4-somite stage. By contrast, Otx2 and Pax6 expression was not affected in Lmx1b-/- embryos. The requirement of specific Lmx1b expression in the MHB was further confirmed by Wnt1-Cre-mediated region-specific conditional knockout of Lmx1b. As a result of these molecular defects, the development of the tectum and cerebellum was severely impaired in Lmx1b-/- mice. Taken together, our results indicate that Lmx1b plays an essential role in the development of the tectum and cerebellum by regulating expression of Fgf8, Wnt1 and several isthmus-related transcription factors in the MHB, and is a crucial component of a cross-regulatory network required for the induction activity of the isthmic organizer in the MHB.