scholarly journals Wnt/β-Catenin and Wnt5a/Ca2+ Pathways Regulate Proliferation and Apoptosis of Keratinocytes in Psoriasis Lesions

2015 ◽  
Vol 36 (5) ◽  
pp. 1890-1902 ◽  
Author(s):  
Yanfei Zhang ◽  
Chen Tu ◽  
Dingwei Zhang ◽  
Yan Zheng ◽  
Zhenhui Peng ◽  
...  

Background/Aims: Wnt5a is overexpressed in psoriasis lesions, however the mechanism by which Wnt5a is involved in the pathogenesis of psoriasis is not clear. To address this, the expression of Wnt5a in psoriatic lesions and its effect on keratinocyte cell proliferation and apoptosis was examined in vitro. Methods: The expression levels of WNT5A, and genes encoding its receptors frizzled2 (FZD2) and frizzled5 (FZD5) were examined in samples obtained from individuals with psoriasis and healthy controls. Knockdown of Wnt5a with short interfering (si)RNAs was performed in cultured HaCaT keratinocytes and normal human keratinocytes (NHK), and the expression of Wnt5a, protein kinase C (PKC), and β-catenin were determined, and cell cycle activity, proliferation and apoptosis were assessed. Results: The expression of WNT5A, FZD2 and FZD5 mRNA and protein were increased in psoriatic lesions. Wnt5a knockdown suppressed proliferation and induced apoptosis in HaCaT and NHK cells. Additionally, expression of PCNA, MKI67, CCND1, BCL2, CTNNB1, and genes encoding PKC and survivin were downregulated, whereas CASP3 was upregulated. The mRNA levels of the Wnt pathway inhibitors DKK1 and SFRP1 were upregulated, Western blotting analyses demonstrated reduction in β-catenin and PKC protein levels. Conclusion: Knockdown of Wnt5a suppresses the proliferation of keratinocytes and induces apoptosis by inhibiting the Wnt/β-catenin or Wnt5a/Ca2+ pathways.

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Yong-Ge Guan ◽  
Jin-Bin Liao ◽  
Kun-Yin Li ◽  
Yu-Cui Li ◽  
Yang Song ◽  
...  

Background. Shaoyao-Gancao Decoction (SGD), a well-known traditional Chinese medicine prescription, has been widely used to treat adenomyosis, dysmenorrhea, abdominal pain, and inflammation in Asia. However, the mechanism underlying the effectiveness of SGD in the treatment of adenomyosis still remains elusive. The present study aimed to investigate the bioactivity of SGD and its underlying molecular mechanisms using cultured human adenomyosis-derived cells.Methods. Human adenomyosis-derived cells were treated with SGD and its major constituents (paeoniflorin and liquiritin)in vitro. Effects of SGD, paeoniflorin, and liquiritin on cell proliferation and apoptosis were examined by MTT assay and flow cytometry analyses. The effects of SGD, paeoniflorin, and liquiritin on the production of PGE2and PGF2αwere assayed using ELISA. ER-αand OTR mRNA expression levels were also evaluated by real-time qRT-PCR.Results. SGD, paeoniflorin, and liquiritin inhibited proliferation and induced apoptosis of human adenomyosis-derived cells in a dose-dependent manner. SGD and paeoniflorin significantly reduced the PGE2and PGF2αproduction. Furthermore, they remarkably decreased the mRNA levels of ER-αand OTR.Conclusions. The results of this study provide possible mechanisms for the bioactivity of SGD for treating adenomyosis and contribute to the ethnopharmacological knowledge about this prescription.


2019 ◽  
Vol 75 (1) ◽  
pp. 58-63 ◽  
Author(s):  
Ahmed Al Saedi ◽  
Craig A. Goodman ◽  
Damian E. Myers ◽  
Alan Hayes ◽  
Gustavo Duque

Abstract Bone marrow fat infiltration is one of the hallmarks of aging and osteoporotic bones. Marrow adipocytes produce substantial amounts of palmitic acid (PA). PA is toxic to bone-forming osteoblasts in vitro, affecting their differentiation, function, and survival. Since rapamycin (RAP)-induced inhibition of target of rapamycin complex 1 (mTORC1) activates autophagy and prevents apoptosis, we hypothesized that RAP may preserve osteoblast viability and reduce PA-induced lipotoxicity. Normal human osteoblasts were incubated with RAP in the presence of a lipotoxic concentration of PA or vehicle for 24 and 48 hours. Expression of LC3 protein levels and the phosphorylation of the direct mTORC1 target p70S6K1-T389 were quantified by Western blot. Lysosomes and autophagosomes were studied using confocal fluorescence imaging, lysotracker, and live-cell imaging. RAP reduced PA-induced apoptosis. In addition, PA-induced autophagosome formation increased substantially over the time-course, an effect that was significantly regulated by the presence of RAP in the media. In addition, LC3I/II ratios were higher in PA-induced cells with RAP whereas p70S6K1-T389 were lower in PA and RAP together. In summary, this study highlights the role of the RAP-sensitive mTORC1 pathway in normal human osteoblasts under lipotoxic conditions. RAP-associated therapies could, potentially, be targeted for specific roles in osteoporosis and aging bone.


BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Chengwu Xiao ◽  
Wei Zhang ◽  
Meimian Hua ◽  
Huan Chen ◽  
Bin Yang ◽  
...  

Abstract Background The tripartite motif (TRIM) family proteins exhibit oncogenic roles in various cancers. The roles of TRIM27, a member of the TRIM super family, in renal cell carcinoma (RCC) remained unexplored. In the current study, we aimed to investigate the clinical impact and roles of TRIM27 in the development of RCC. Methods The mRNA levels of TRIM27 and Kaplan–Meier survival of RCC were analyzed from The Cancer Genome Atlas database. Real-time PCR and Western blotting were used to measure the mRNA and protein levels of TRIM27 both in vivo and in vitro. siRNA and TRIM27 were exogenously overexpressed in RCC cell lines to manipulate TRIM27 expression. Results We discovered that TRIM27 was elevated in RCC patients, and the expression of TRIM27 was closely correlated with poor prognosis. The loss of function and gain of function results illustrated that TRIM27 promotes cell proliferation and inhibits apoptosis in RCC cell lines. Furthermore, TRIM27 expression was positively associated with NF-κB expression in patients with RCC. Blocking the activity of NF-κB attenuated the TRIM27-mediated enhancement of proliferation and inhibition of apoptosis. TRIM27 directly interacted with Iκbα, an inhibitor of NF-κB, to promote its ubiquitination, and the inhibitory effects of TRIM27 on Iκbα led to NF-κB activation. Conclusions Our results suggest that TRIM27 exhibits an oncogenic role in RCC by regulating NF-κB signaling. TRIM27 serves as a specific prognostic indicator for RCC, and strategies targeting the suppression of TRIM27 function may shed light on future therapeutic approaches.


Pathobiology ◽  
2021 ◽  
pp. 1-12
Author(s):  
Ying Xie ◽  
Yuanyuan Ruan ◽  
Huimei Zou ◽  
Yixin Wang ◽  
Xin Wu ◽  
...  

<b><i>Objective:</i></b> The goal of the present study was to determine the expression of yes-associated protein 1 (YAP1) in renal tissues of mice with lupus nephritis (LN) and elucidate its role in the progression of renal fibrosis. <b><i>Methods:</i></b> C57BL/6 mice and MRL/lpr mice were selected for experimental comparison. Mouse kidney tissues were removed and sectioned for hematoxylin and eosin staining, Masson’s trichome staining, Sirius staining, and immunohistochemistry. The mRNA and protein levels of YAP1 in mouse kidney tissues were detected, and the correlation between YAP1 and fibronectin (FN) mRNA levels was analyzed. Mouse renal epithelial cells were used for in vitro experiments. After transfection and stimulation, the cells were divided into 4 groups, namely the C57BL/6 serum group (group 1), the MRL/lpr serum group (group 2), the MRL/lpr serum + siRNA-negative control group (group 3), and the MRL/lpr serum + siRNA-YAP1 group (group 4). Epithelial-mesenchymal transition (EMT) markers in each group were detected by Western blotting and immunofluorescence staining. Serum creatinine, blood urea nitrogen, and urinary protein levels were detected and assessed for their correlation with YAP1 mRNA levels by Spearman’s analysis. <b><i>Results:</i></b> Compared to C57BL/6 mice, MRL/lpr mice exhibited obvious changes in fibrosis in renal tissues. In addition, YAP1 expression was significantly higher in the renal tissues of MRL/lpr mice than in those of C57BL/6 mice, and YAP1 mRNA levels were positively correlated with those of FN. YAP1 silencing in lupus serum-stimulated cells could effectively relieve serum-induced EMT. Finally, we observed that YAP1 mRNA levels in mouse kidney tissue were significantly and positively correlated with the degree of renal function injury. <b><i>Conclusion:</i></b> YAP1 expression in the kidney tissues of LN mice was higher than that observed in normal mice, indicating that YAP1 may play an important role in the occurrence and development of LN.


2020 ◽  
Author(s):  
Maik Hintze ◽  
Sebastian Griesing ◽  
Marion Michels ◽  
Birgit Blanck ◽  
Lena Wischhof ◽  
...  

AbstractWe investigated the contribution of apoptosis-inducing factor (AIF), a key regulator of mitochondrial biogenesis, in supporting hair growth. We report that pelage abnormalities developed during hair follicle (HF) morphogenesis in Harlequin (Hq) mutant mice. Fragility of the hair cortex was associated with decreased expression of genes encoding structural hair proteins, though key transcriptional regulators of HF development were expressed at normal levels. Notably, Aifm1 (R200 del) knockin males and Aifm1(R200 del)/Hq females showed minor hair defects, despite substantially reduced AIF levels. Furthermore, we cloned the integrated ecotropic provirus of the Aifm1Hq allele. We found that its overexpression in wild-type keratinocyte cell lines led to down-regulation of HF-specific Krt84 and Krtap3-3 genes without altering Aifm1 or epidermal Krt5 expression. Together, our findings imply that pelage paucity in Hq mutant mice is mechanistically linked to severe AIF deficiency and is associated with the expression of retroviral elements that might potentially influence the transcriptional regulation of structural hair proteins.


2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii348-iii348
Author(s):  
Tina Huang ◽  
Andrea Piunti ◽  
Elizabeth Bartom ◽  
Jin Qi ◽  
Rintaro Hashizume ◽  
...  

Abstract BACKGROUND Histone H3.3 mutation (H3F3A) occurs in 50% of cortical pediatric high-grade gliomas. This mutation replaces glycine 34 with arginine or valine (G34R/V), impairing SETD2 activity (H3K36-specific trimethyltransferase), resulting in reduced H3K36me on H3G34V nucleosomes relative to wild-type. This contributes to genomic instability and drives distinct gene expressions associated with tumorigenesis. However, it is not known if this differential H3K36me3 enrichment is due to H3G34V mutant protein alone. Therefore, we set to elucidate the effect of H3G34V on genomic H3K36me3 enrichment in vitro. METHODS Doxycycline-inducible short hairpin RNA (shRNA) against H3F3A was delivered via lentivirus to established H3G34V mutant pediatric glioma cell line KNS42, and H3G34V introduced into H3.3 wild type normal human astrocytes (NHA). Transfections were confirmed by western blot, fluorescent imaging, and flow cytometry, with resulting H3.3WT and H3K36me3 expression determined by western blot. H3.3WT, H3K36me3, and H3G34V ChIP-Seq was performed to evaluate genomic enrichment. RESULTS Complete knockdown of H3G34V was achieved with DOX-induced shRNA, with no change in total H3.3, suggesting disproportionate allelic frequency of genes encoding H3.3 (H3F3A and H3F3B). Modest increase in H3K36me3 occurred after H3F3A-knockdown from KNS42, suggesting H3G34V alone impacts observed H3K36me3 levels. Distinct H3K36me3 genomic enrichment was observed with H3G34V knock-in. CONCLUSIONS We demonstrate that DOX-inducible knockdown of H3F3A in an H3G34V mutant pediatric glioma cells and H3G34V mutation transduction in wild-type astrocytes affects H3K36me3 expression. Further evaluation by ChIP-Seq analysis for restoration of wild-type genomic H3K36me3 enrichment patterns with H3G34V knockdown, and mutant H3K36me3 patterns with H3G34V transduction, is currently underway.


Diabetologia ◽  
2021 ◽  
Author(s):  
Juliana de Almeida-Faria ◽  
Daniella E. Duque-Guimarães ◽  
Thomas P. Ong ◽  
Lucas C. Pantaleão ◽  
Asha A. Carpenter ◽  
...  

Abstract Aims/hypothesis Levels of the microRNA (miRNA) miR-126-3p are programmed cell-autonomously in visceral adipose tissue of adult offspring born to obese female C57BL/6J mice. The spectrum of miR-126-3p targets and thus the consequences of its dysregulation for adipocyte metabolism are unknown. Therefore, the aim of the current study was to identify novel targets of miR-126-3p in vitro and then establish the outcomes of their dysregulation on adipocyte metabolism in vivo using a well-established maternal obesity mouse model. Methods miR-126-3p overexpression in 3T3-L1 pre-adipocytes followed by pulsed stable isotope labelling by amino acids in culture (pSILAC) was performed to identify novel targets of the miRNA. Well-established bioinformatics algorithms and luciferase assays were then employed to confirm those that were direct targets of miR-126-3p. Selected knockdown experiments were performed in vitro to define the consequences of target dysregulation. Quantitative real-time PCR, immunoblotting, histology, euglycaemic–hyperinsulinaemic clamps and glucose tolerance tests were performed to determine the phenotypic and functional outcomes of maternal programmed miR-126-3p levels in offspring adipose tissue. Results The proteomic approach confirmed the identity of known targets of miR-126-3p (including IRS-1) and identified Lunapark, an endoplasmic reticulum (ER) protein, as a novel one. We confirmed by luciferase assay that Lunapark was a direct target of miR-126-3p. Overexpression of miR-126-3p in vitro led to a reduction in Lunapark protein levels and increased Perk (also known as Eif2ak3) mRNA levels and small interference-RNA mediated knockdown of Lunapark led to increased Xbp1, spliced Xbp1, Chop (also known as Ddit3) and Perk mRNA levels and an ER stress transcriptional response in 3T3-L1 pre-adipocytes. Consistent with the results found in vitro, increased miR-126-3p expression in adipose tissue from adult mouse offspring born to obese dams was accompanied by decreased Lunapark and IRS-1 protein levels and increased markers of ER stress. At the whole-body level the animals displayed glucose intolerance. Conclusions/interpretation Concurrently targeting IRS-1 and Lunapark, a nutritionally programmed increase in miR-126-3p causes adipose tissue insulin resistance and an ER stress response, both of which may contribute to impaired glucose tolerance. These findings provide a novel mechanism by which obesity during pregnancy leads to increased risk of type 2 diabetes in the offspring and therefore identify miR-126-3p as a potential therapeutic target. Graphical abstract


Blood ◽  
2008 ◽  
Vol 111 (5) ◽  
pp. 2797-2805 ◽  
Author(s):  
Feng-Ting Liu ◽  
Samir G. Agrawal ◽  
John G. Gribben ◽  
Hongtao Ye ◽  
Ming-Qing Du ◽  
...  

Proapoptotic Bcl-2 family member Bax is a crucial protein in the induction of apoptosis, and its activation is required for this process. Here we report that Bax is a short-lived protein in malignant B cells and Bax protein levels decreased rapidly when protein synthesis was blocked. Malignant B cells were relatively resistant to tumor necrosis factor–related apoptosis inducing ligand (TRAIL)–induced apoptosis, and this correlated with low basal Bax protein levels. Furthermore, during treatment with TRAIL, the resistant cell lines showed prominent Bax degradation activity. This degradation activity was localized to mitochondrial Bax and could be prevented by truncated Bid, a BH3-only protein; in contrast, cytosolic Bax was relatively stable. The proteasome inhibitor bortezomib is a potent drug in inducing apoptosis in vitro in malignant B-cell lines and primary chronic lymphocytic leukemic (CLL) cells. In CLL cells, bortezomib induced Bax accumulation, translocation to mitochondria, conformational change, and oligomerization. Accumulation and stabilization of Bax protein by bortezomib-sensitized malignant B cells to TRAIL-induced apoptosis. This study reveals that Bax instability confers resistance to TRAIL, which can be reversed by Bax stabilization with a proteasome inhibitor.


2002 ◽  
Vol 365 (1) ◽  
pp. 133-145 ◽  
Author(s):  
Nadine CHOUINARD ◽  
Kristoffer VALERIE ◽  
Mahmoud ROUABHIA ◽  
Jacques HUOT

Human keratinocytes respond to UV rays by developing a fast adaptive response that contributes to maintaining their functions and survival. We investigated the role of the mitogen-activated protein kinase pathways in transducing the UV signals in normal human keratinocytes. We found that UVA, UVB or UVC induced a marked and persistent activation of p38, whereas c-Jun N-terminal kinase or extracellular signal-regulated kinase were less or not activated respectively. Inhibition of p38 activity by expression of a dominant-negative mutant of p38 or with SB203580 impaired cell viability and led to an increase in UVB-induced apoptosis. This sensitization to apoptosis was independent of caspase activities. Inhibition of p38 did not sensitize transformed HaCaT keratinocytes to UVB-induced apoptosis. In normal keratinocytes, expression of a dominant-negative mutant of p53 increased UVB-induced cell death, pointing to a role for p53. In these cells, UVB triggered a p38-dependent phosphorylation of p53 on Ser-15. This phosphorylation was associated with an SB203580-sensitive accumulation of p53, even in the presence of a serine phosphatase inhibitor. Accumulated p53 was localized mainly in the cytoplasm, independently of CRM1 nuclear export. In HaCaT cells, p53 was localized exclusively in the nucleus and its distribution and level were not affected by UVB or p38 inhibition. However, UVB induced an SB203580-insensitive phosphorylation on Ser-15 of mutated p53. Overall, our results suggest that, in normal human keratinocytes, protection against UVB depends on p38-mediated phosphorylation and stabilization of p53 and is tightly associated with the cytoplasmic sequestration of wild-type p53. We conclude that the p38/p53 pathway plays a key role in the adaptive response of normal human keratinocytes against UV stress.


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