ABSTRACT
Migration of myoblasts derived from the occipital somites is essential for tongue morphogenesis. However, the molecular mechanisms of myoblast migration remain elusive. In this study, we report that deletion of Isl1 in the mouse mandibular epithelium leads to aglossia due to myoblast migration defects. Isl1 regulates the expression pattern of chemokine ligand 12 (Cxcl12) in the first branchial arch through the Shh/Wnt5a cascade. Cxcl12+ mesenchymal cells in Isl1ShhCre embryos were unable to migrate to the distal region, but instead clustered in a relatively small proximal domain of the mandible. CXCL12 serves as a bidirectional cue for myoblasts expressing its receptor CXCR4 in a concentration-dependent manner, attracting Cxcr4+ myoblast invasion at low concentrations but repelling at high concentrations. The accumulation of Cxcl12+ mesenchymal cells resulted in high local concentrations of CXCL12, which prevented Cxcr4+ myoblast invasion. Furthermore, transgenic activation of Ihh alleviated defects in tongue development and rescued myoblast migration, confirming the functional involvement of Hedgehog signaling in tongue development. In summary, this study provides the first line of genetic evidence that the ISL1/SHH/CXCL12 axis regulates myoblast migration during tongue development.
Subject(s)
Chemokine CXCL12 , Hedgehog Proteins , LIM-Homeodomain Proteins , Signal Transduction , Tongue , Transcription Factors , Animals , Mice , Cell Movement/genetics , Hedgehog Proteins/genetics , Hedgehog Proteins/metabolism , Ligands , Signal Transduction/genetics , Tongue/embryology , LIM-Homeodomain Proteins/genetics , Transcription Factors/genetics , Chemokine CXCL12/geneticsABSTRACT
Depleted uranium (DU) retains the radiological toxicities, which accumulates preferentially in the kidneys. Hedgehog (Hh) pathway plays a critical role in tissue injury. However, the role of Hh in DU-induced nephrotoxicity was still unclear. This study was carried out to investigate the effect of Gli2, which was an important transcription effector of Hh signaling, on DU induced nephrotoxicity. To clarify it, CK19 positive tubular epithelial cells specific Gli2 conditional knockout (KO) mice model was exposed to DU, and then histopathological damage and Hh signaling pathway activation was analyzed. Moreover, HEK-293 T cells were exposed to DU with Gant61 or Gli2 overexpression, and cytotoxicity of DU as analyzed. Results showed that DU caused nephrotoxicity accompanied by activation of Hh signaling pathway. Meanwhile, genetic KO of Gli2 reduced DU-induced nephrotoxicity by normalizing biochemical indicators and reducing Hh pathway activation. Pharmacologic inhibition of Gli1/2 by Gant61 reduced DU induced cytotoxicity by inhibiting apoptosis, ROS formation and Hh pathway activation. However, overexpression of Gli2 aggravated DU-induced cytotoxicity by increasing the levels of apoptosis and ROS formation. Taken together, these results revealed that Hh signaling negatively regulated DU-inducted nephrotoxicity, and that inhibition of Gli2 might serve as a promising nephroprotective target for DU-induced kidney injury.
Subject(s)
Hedgehog Proteins , Kidney , Mice, Knockout , Signal Transduction , Zinc Finger Protein Gli2 , Animals , Hedgehog Proteins/metabolism , Hedgehog Proteins/genetics , Humans , HEK293 Cells , Signal Transduction/drug effects , Zinc Finger Protein Gli2/metabolism , Zinc Finger Protein Gli2/genetics , Kidney/drug effects , Kidney/pathology , Kidney/metabolism , Mice , Uranium/toxicity , Apoptosis/drug effects , Pyridines/pharmacology , Pyridines/toxicity , Male , Kidney Diseases/chemically induced , Kidney Diseases/pathology , Kidney Diseases/metabolism , Pyrimidines/pharmacology , Pyrimidines/toxicity , Mice, Inbred C57BL , Reactive Oxygen Species/metabolismABSTRACT
Hexavalent chromium Cr (VI) is a primary human carcinogen with damaging toxic effects on multiple organs. Cr (VI) exposure can induce hepatotoxicity through oxidative stress, but its exact mechanism of action was still unclear. In our study, a model of acute Cr (VI) induced liver injury was established by exposing mice to different concentrations (0, 40, 80, and 160 mg/kg) of Cr (VI); RNA-seq was used to characterize changes in liver tissue transcriptome of C57BL/6 mice after exposing to 160 mg/kg Bw of Cr (VI). Changes in liver tissue structures, proteins, and genes were observed by hematoxylin and eosin (H&E), western blot, immunohistochemistry and RT-PCR. After Cr (VI) exposure, abnormal liver tissue structure, hepatocyte injury, and hepatic inflammatory response were observed in mice in a dose-dependent manner. RNA-seq transcriptome results indicated that oxidative stress, apoptosis, and inflammatory response pathways were increased after Cr (VI) exposure; KEGG pathway analysis found that activation of NF-κB signaling pathway was significantly upregulated. Consistent with the RNA-seq results, immunohistochemistry showed that Cr (VI) exposure resulted in infiltrating of Kupffer cells and neutrophils, increasing expression of inflammatory factors (TNF-α, IL-6, IL-1ß), and activating of NF-κB signaling pathways (p-IKKα/ß and p-p65). However, ROS inhibitor, N-acetyl-L-cysteine (NAC), could reduce infiltration of Kupffer cells and neutrophils and expression of inflammatory factors. Besides, NAC could inhibit NF-κB signaling pathway activation, and alleviate Cr (VI)-induced liver tissue damage. Our findings strongly suggested that inhibition of ROS by NAC might help in the development of new strategies for Cr (VI)-associated liver fibrosis. Our findings revealed for the first time that Cr (VI) induced liver tissue damage through the inflammatory response mediated by the NF-κB signaling pathway, and inhibition of ROS by NAC might help in the development of new strategies for Cr (VI)-associated hepatotoxicity.
Subject(s)
Chemical and Drug Induced Liver Injury , NF-kappa B , Mice , Humans , Animals , NF-kappa B/metabolism , Reactive Oxygen Species/metabolism , Mice, Inbred C57BL , Signal Transduction , Chromium/toxicity , Acetylcysteine/pharmacologyABSTRACT
With the spread of hexavalent chromium (Cr(VI)) contamination, Cr(VI)-induced hepatotoxicity has attracted increasing attention in recent years. To date, however, the exact mechanism of Cr(VI) toxicity remains unclear. In this study, we investigated the role of apoptosis signal-regulating kinase 1 (ASK1)/c-Jun amino-terminal kinase (JNK) in Cr(VI)-induced hepatic toxicity and the possible related mechanisms. AML-12 hepatocyte cell-lines were treated with 0, 1, 4, and 16 µmol/Lof Cr(VI) with or without GS-444271 (an ASK1 inhibitor). Adult male mice were administered with 0, 2, 8, and 32 mg/kg body mass (BM)/day of Cr(VI) for 5 days. The level of hepatocyte apoptosis/proliferation, generation of reactive oxygen species (ROS), and expression levels of mRNAs and proteins related to ASK1/JNK and nuclear factor-E2-related factor 2 (Nrf2) signaling were assessed. Results showed that high Cr(VI) exposure induced hepatocyte apoptosis and liver injury by generation of ROS and down-regulation of Nrf2 signaling. In addition, ASK1/JNK signaling activity was upregulated in the Cr(VI)-treated group. Furthermore, GS-444217 treatment significantly rescued Cr(VI)-induced hepatocyte apoptosis and liver dysfunction in vitro and in vivo by down-regulation of ASK1/JNK signaling. Thus, ASK1/JNK signaling appears to play an important role in Cr(VI)-induced hepatocyte apoptosis and liver injury. This study should help improve our understanding of the mechanism of Cr(VI)-induced liver injury and provide support for future investigations on liver disease therapy.
Subject(s)
MAP Kinase Kinase Kinase 5 , NF-E2-Related Factor 2 , Animals , Apoptosis , Chromium/metabolism , Chromium/toxicity , Hepatocytes/metabolism , JNK Mitogen-Activated Protein Kinases/metabolism , MAP Kinase Kinase Kinase 5/metabolism , Male , Mice , NF-E2-Related Factor 2/metabolism , Reactive Oxygen Species/metabolismABSTRACT
The current study investigated the regulation and the spatiotemporal expression pattern of Errfi1 and Ifrd1, genex encoding factors that regulate differentiation and cessation of cell division, in the rat ovary during the periovulatory period. Immature female rats (22-23 days old) were injected with pregnant-mare serum gonadotropin to stimulate folliculogenesis, followed by human chorionic gonadotropin (hCG) to induce ovulation. Ovaries, granulosa cells, theca-interstitial cells, or cumulus oocyte complexes (COCs) were collected at various times after hCG administration (n = 3 per time point). Expression analysis revealed that Errfi1 and Ifrd1 were highly induced in the ovary, although their spatiotemporal expression differed: In situ hybridization analysis demonstrated that Errfi1 mRNA expression was initially induced in theca-interstitial cells at 4 and 8 hr after hCG, then transitioned to granulosa cells at 12 hr, and decreased in newly forming corpora lutea at 24 hr. Ifrd1 mRNA, on the other hand, was primarily induced in granulosa cells, and expression remained elevated in newly forming corpora lutea. Interestingly, Errfi1 and Ifrd1 were also expressed in the COC, suggesting a potential role in cumulus cell expansion or oocyte maturation. Inhibition of progesterone or prostaglandin synthesis reduced Errfi1 and Ifrd1 transcription, whereas inhibition of epidermal growth factor signaling inhibited only Errfi1 mRNA abundance. Down-regulation of both genes led to further suppression of progesterone. Our findings thus suggest that the stimulation of Errfi1 and Ifrd1 may be important for theca and granulosa cell differentiation and COC expansion. Mol. Reprod. Dev. 83: 714-723, 2016 © 2016 Wiley Periodicals, Inc.
Subject(s)
Cumulus Cells/metabolism , Gene Expression Regulation/physiology , Immediate-Early Proteins/biosynthesis , Membrane Proteins/biosynthesis , Ovulation/physiology , Theca Cells/metabolism , Tumor Suppressor Proteins/biosynthesis , Animals , Chorionic Gonadotropin/pharmacology , Cumulus Cells/cytology , Female , Gene Expression Regulation/drug effects , Humans , Ovulation/drug effects , Progesterone/pharmacology , Rats , Rats, Sprague-Dawley , Theca Cells/cytologyABSTRACT
BACKGROUND: Timely identification and intervention of psychological disorders bear significant import in ameliorating the ensuing therapeutic trajectories in primary bone tumor patients. Moreover, perturbations in thyroxine and thyroid-stimulating hormone (TSH) levels have been linked to manifestations of depressive and anxiety-related symptoms. However, the precise interplay governing the nexus of anxiety, depression, and the levels of thyroxine and TSH within the context of primary bone tumor patients remains presently unexplored. OBJECTIVE: The objective of this study is to investigate the potential correlation between the hypothalamus- pituitary-thyroxine (HPT) axis and the depressive as well as anxious states observed in patients afflicted with bone tumors. METHODS: Patients with primary bone tumors were required to accept the assessments of anxiety and depressive symptoms as well as thyroid axis hormone concentrations. The depressive and anxiety symptoms were assessed using the Hamilton Depression Rating Scale (HAMD) and the Hamilton Anxiety Scale (HAMA) score. During each follow-up, peripheral venous blood samples were collected for subsequent analysis using radioimmunoassay methods to measure serum- free T3, free T4, and TSH levels, with the calculated free T3 to free T4 ratio indicating peripheral free T4 to free T3 conversion. Tests for trend were conducted to assess thyroid axis hormone concentrations, HAMA scores, and HAMD scores, while the correlation between HAMA or HAMD scores and thyroid axis hormone concentrations was examined through univariate regression analyses. RESULTS: The study included 30 primary bone tumor patients. Initial high HAMA and HAMD scores decreased over a year after surgery (P < 0.05), reflecting diminishing anxiety and depression. TSH levels reduced postoperatively, contrasting with increased free-T3 and free-T4 levels (p < 0.01). Multivariate analysis affirmed that positive correlations were noted between TSH and anxiety/depression scores, while free-T3 correlated negatively, adjusted for demographic factors (p < 0.05). No significant associations emerged between HAMA/HAMD scores and free-T4 or free-T3 to free-T4 ratio (p > 0.05). CONCLUSION: The early identification of the low T3 syndrome could prove instrumental in both intervening and preventing adverse emotional states associated with primary bone tumors.
ABSTRACT
BACKGROUND: Adenocarcinoma is a non-small-cell lung cancer that is common cancer in both genders, and has poor clinical outcomes. We aimed to evaluate the role of cytoskeleton-associated protein 2 (CKAP2), its prognostic significance, and the relationship between CKAP2 expression and lung adenocarcinoma driver genes. METHODS: The expression of CKAP2 was studied by immunohistochemical staining of specimens from 88 patients with lung adenocarcinoma. The correlation between clinicopathological features and CKAP2 expression was analyzed. Kaplan-Meier analysis and Cox proportional hazard models were used to examine the prognostic value of CKAP2 in terms of overall survival (OS). The correlation between epidermal growth factor receptor (EGFR) mutation, anaplastic lymphoma kinase (ALK) rearrangement, and CKAP2 expression was analyzed. All histological samples were detected by fluorescence in situ hybridization for EGFR mutations and ALK rearrangements. RESULTS: Eighty-eight patients with positive CKAP2 expression were observed in this study. Patients with high levels of CKAP2 expression were associated with OS (P = .021). Multivariate Cox regression analysis disclosed that positive CKAP2 expression (P = .043) could independently predict unfavorable OS. In addition, CKAP2 expression was not associated with EGFR mutation (P = .219) and ALK rearrangement (P = .389) in lung adenocarcinoma patients. CONCLUSION: High expression of CKAP2 may serve as a marker of poor prognosis in lung adenocarcinoma.
Subject(s)
Adenocarcinoma of Lung , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Adenocarcinoma of Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Cytoskeletal Proteins/genetics , Cytoskeleton , ErbB Receptors/genetics , Female , Gene Rearrangement , Humans , In Situ Hybridization, Fluorescence , Lung Neoplasms/pathology , Male , Mutation , Prognosis , Receptor Protein-Tyrosine Kinases/geneticsABSTRACT
Mandibular patterning information initially resides in the epithelium during development. However, how transcriptional regulation of epithelium-derived signaling controls morphogenesis of the mandible remains elusive. Using ShhCre to target the mandibular epithelium, we ablated transcription factor Islet1, resulting in a distally truncated mandible via unbalanced cell apoptosis and decreased cell proliferation in the distal mesenchyme. Loss of Islet1 caused a lack of cartilage at the distal tip, leading the fusion of two growing mandibular elements surrounding the rostral process of Meckel's cartilage. Loss of Islet1 results in dysregulation of mesenchymal genes important for morphogenesis of the mandibular arch. We revealed that Islet1 is required for the activation of epithelial ß-catenin signaling via repression of Wnt antagonists. Reactivation of ß-catenin in the epithelium of the Islet1 mutant rescued mandibular morphogenesis through sonic hedgehog (SHH) signaling to the mesenchyme. Furthermore, overexpression of a transgenic hedgehog ligand in the epithelium also partially restored outgrowth of the mandible. These data reveal functional roles for an ISLET1-dependent network integrating ß-catenin/SHH signals in mesenchymal cell survival and outgrowth of the mandible during development.