Journal of Molecular Histology最新文献

The Omi/HtrA2 inhibitor 5-[5-(2-nitrophenyl) furfuryliodine]-1,3-diphenyl-2-thiobarbituric acid (Ucf-101) has shown neuroprotective effects in the central nervous system. However, whether Ucf-101 can protect retinal ganglion cells (RGCs) after retinal ischemia/reperfusion (IR) has not been investigated. We aimed to investigate the effects of Ucf-101 on RGCs apoptosis and inflammation after IR-induced retinal injury in mice. We injected Ucf-101 into the mouse vitreous body immediately after IR injury. After 7 days, hematoxylin and eosin staining was conducted to assess retinal tissue damage. Next, retrograde labeling with FluoroGold, counting of RGCs and TUNEL staining were conducted to evaluate apoptosis. Immunohistochemistry, immunofluorescence staining, and western blotting were conducted to analyze protein levels. IR injury-induced retinal tissue damage could be prevented by Ucf-101 treatment. The number of TUNEL-positive RGCs was reduced by Ucf-101 treatment in mice with IR injury. Ucf-101 treatment inhibited the upregulation of Bax, cleaved caspase-3 and cleaved caspase-9 and activated the JNK/ERK/P38 signaling pathway. Furthermore, Ucf-101 treatment inhibited the upregulation of glial fibrillary acidic protein (GFAP), vimentin, Iba1 and CD68 in mice with IR injury. Ucf-101 prevents retinal tissue damage, improves the survival of RGCs, and suppresses microglial overactivation after IR injury. Ucf-101 might be a potential target to prevent RGCs apoptosis and inflammation in neurodegenerative eye diseases.

Anshen Shumai Decoction (ASSMD) is traditionally employed to manage coronary artery disease arrhythmias. Its protective efficacy against myocardial infarction remains to be elucidated. This investigation employed a rat model of myocardial infarction, achieved through the ligation of the left anterior descending (LAD) coronary artery, followed by a 28-day administration of ASSMD. The study observed the decoction’s mitigative impact on myocardial injury, with gene regulation effects discerned through transcriptomic analysis. Furthermore, ASSMD’s influence on cardiomyocyte apoptosis and fibrotic protein secretion was assessed using an embryonic rat cardiomyocyte cell line (H9c2) under hypoxic conditions and rat cardiac fibroblasts subjected to normoxic culture conditions with TGF-β. A functional rescue assay involving overexpression of FOS and Early Growth Response Factor 1 (EGR1), combined with inhibition of the p38 Mitogen-activated Protein Kinase (MAPK) pathway, was conducted. Results indicated that ASSMD significantly curtailed cardiomyocyte apoptosis and myocardial fibrosis in infarcted rats, primarily by downregulating FOS and EGR1 gene expression and inhibiting the upstream p38 MAPK pathway. These actions of ASSMD culminated in reduced expression of pro-apoptotic, collagen, and fibrosis-associated proteins, conferring myocardial protection and anti-fibrotic effects on cardiac fibroblasts.

Background: Sorting nexin 14 (SNX14) is a member of the sorting junction protein family. Its specific roles in cancer development remain unclear. Therefore, in this study, we aimed to determine the effects and underlying mechanisms of SNX14 on autophagy of breast cancer cells to aid in the therapeutic treatment of breast cancer. Methods: In this study, we performed in vitro experiments to determine the effect of SNX14 on breast cancer cell growth. Moreover, we used an MCF7 breast cancer tumor-bearing mouse model to confirm the effect of SNX14 on tumor cell growth in vivo. We also performed western blotting and quantitative polymerase chain reaction to identify the mechanism by which SNX14 affects breast cancer MCF7 cells. Results: We found that SNX14 regulated the onset and progression of breast cancer by promoting the proliferation and inhibiting the autophagy of MCF7 breast cancer cells. In vivo experiments further confirmed that SNX14 knockdown inhibited the tumorigenicity and inhibited the growth of tumor cells in tumor tissues of nude mice. In addition, western blotting analysis revealed that SNX14 modulate the autophagy of MCF7 breast cancer cells via the phosphoinositide 3-kinase/protein kinase B/mechanistic target of rapamycin kinase signaling pathway. Conclusion: Our findings indicate that SNX14 is an essential tumor-promoting factor in the development of breast cancer.

Diapause is an endocrine-mediated metabolic and growth arrest state in response to unfavorable external environments. The nematode Caenorhabditis elegans can enter diapause/arrest during embryonic, larval, or adult stages when subjected to detrimental external environments. Larval stage 1 (L1) arrest happens when animals hatch without food. Previous work has shown that the insulin pathway plays a prominent role in regulating L1 arrest. However, the downstream signal molecular mechanisms and biomarkers are still missing. In this study, we showed that SaPosin-like Protein family member SPP-5 is significantly upregulated during L1 arrest, suggesting that it could act as an L1 arrest biomarker. Using RNA interference we demonstrated that spp-5  knockdown accelerated larval development, while the overexpression resulted in L1 arrest. Consistently, SPP-5 level was significantly up-regulated in the L1 arrest daf-2(e1370) mutants, and spp-5(RNAi) suppressed the daf-2(e1370) induced L1 arrest. These results suggest that SPP-5 can serve as an L1 arrest biomarker and promote the arrest probably via the insulin signaling pathway.

Systemic lupus erythematosus (SLE) is a persistent autoimmune disorder that can culminate in lupus nephritis (LN), an intricate renal complication. In pursuit of unraveling the intricate molecular underpinnings governing LN progression, we conducted bioinformatics analysis employing gene expression data sourced from the GSE32591 dataset. Our scrutiny revealed a panoply of differentially expressed genes (DEGs) within the glomerulus and tubulointerstitial compartments of LN patients. Enrichment analysis for DEGs engaged in diverse processes, encompassing virus defense, viral life cycle, cell adhesion molecules, and the NOD-like receptor signaling pathway. Notably, STAT1 emerged as an eminent central hub gene intrinsically tied to NOD-like receptor signaling. To explore the functional significance of STAT1 in the context of LN, MRL-lpr mice model was used to knockout STAT1. The results unveiled that STAT1 silencing yielded a migratory effect on kidney injury, concurrently curbing inflammatory markers. Meanwhile, knockout STAT1 also reduced NLRP3 expression and Cleaved caspase-1 expression. These findings offer tantalizing prospects for targeting STAT1 as a potential therapeutic conduit in the management of LN.

Obesity is defined by increased adipose tissue volume and has become a major risk factor for reproduction. Recent studies have revealed a substantial link between obesity and epigenetics. The epigenome is dynamically regulated mainly by DNA methylation. DNA methylation, which is controlled by DNA methyltransferases (Dnmts), has been widely studied because it is essential for imprinting and regulation of gene expression. In our previous study, we showed that the levels of Dnmt1, Dnmt3a and global DNA methylation was dramatically altered in the testis and ovary of high-fat diet (HFD)-induced obese mice. However, the effect of HFD on Dnmts and global DNA methylation in mouse uterus has not yet been demonstrated. Therefore, in the present study, we aimed to evaluate the effect of HFD on the level of Dnmt1, Dnmt3a, Dnmt3b, Dnmt3l and global DNA methylation in uterus. Our results showed that HFD significantly altered the levels of Dnmts and global DNA methylation in the uterus. The total expression of Dnmt1, Dnmt3a and Dnmt3b was significantly upregulated, while level of Dnmt3l and global DNA methylation were dramatically decreased (p < 0.05). Furthermore, we observed that the expression of Dnmt3b and Dnmt3l was significantly increased in endometrium including gland and epithelium (p < 0.05). Although Dnmt3b was the only protein whose expression significantly increased, the level of global DNA methylation and Dnmt3l significantly decreased in stroma and myometrium (p < 0.05). In conclusion, our results show for the first time that obesity dramatically alters global DNA methylation and expression of Dnmts, and decreased DNA methylation and Dnmt expression may cause abnormal gene expression, especially in the endometrium.

Zinc (Zn) is a normal trace element in mineralizing tissues, but it is unclear whether it is primarily bound to the mineral phase or to organic molecules involved in the mineralization process, or both. Tissue-nonspecific alkaline phosphatase (TNAP) is a Zn metalloenzyme with two Zn ions bound to the M1 and M2 catalytic sites that functions to control the phosphate/pyrophosphate ratio during biomineralization. Here, we studied aortas from Tagln-Cre ^+/−; Hprt^ALP/Y TNAP overexpressor (TNAP-OE) mice that develop severe calcification. Zn histochemistry was performed using the sulfide-silver staining method in combination with a Zn partial extraction procedure to localize mineral-bound (mineral Zn) and TNAP-bound Zn (tenacious Zn), since soluble Zn (loose Zn) is extracted during fixation of the specimens. Two synthetic bone mineral composites with different Zn content, bone ash, and rat epiphyseal growth plate cartilage were used as controls for Zn staining. In order to correlate the distribution of mineral and tenacious Zn with the presence of mineral deposits, the aortas were examined histologically in unstained and stained thin sections using various light microscopy techniques. Our results show that 14 and 30 dpn, TNAP is concentrated in the calcifying matrix and loses Zn as Ca²⁺ progressively displaces Zn²⁺ at the M1 and M2 metal sites. Thus, in addition to its catalytic role TNAP has an additional function at calcifying sites as a Ca-binding protein.

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Osteoporosis is a progressive skeletal disease which is characterized by reduced bone mass and degradation of bone microstructure. Mesenchymal stem cells (MSCs) have the potential to inhibit osteoporosis since they are multipotent stem cells that can differentiate into multiple types of cells including osteoblasts. Hence the mechanism of osteogenic differentiation of MSCs deserves comprehensive study. Here we report that KLF9 is a novel regulator in osteogenic differentiation of MSCs. We observed that depletion of KLF9 can largely compromise the osteogenic differentiation ability of MSCs. In addition, we revealed that inhibition of the PI3K-Akt pathway could also affect osteogenic differentiation since KLF9 depletion inhibits PI3K expression. Finally, we discovered that KLF9 expression can be induced by dexamethasone which is an essential component in osteogenic induction medium. Taken together, our study provides new insights into the regulatory role of KLF9 in osteogenic differentiation of MSCs.

A growing body of evidence suggests that elevated sucrose intake may contribute to the development of neurological disorders. Recognizing that regular exercise has the potential to reduce the occurrence of neuromuscular disorders, the present research investigated the impact of exercise on the redox status of the hypothalamus in mitigating the adverse effects associated with high sucrose intake. Forty Wistar albino rats were subjected to a high sucrose diet, with some groups engaging in exercise for a duration of 3 months. The exercise regimen was found to sustain the redox balance in the hypothalamus. In summary, the consumption of a high sucrose diet resulted in the disturbance of the histological morphology of the hypothalamus, accompanied by an increased percentage of caspase-3 positive cells. Additionally, the high sucrose diet disrupted the oxidant/antioxidant ratio in favor of oxidants, leading to elevated levels of AOPPs and AGEP. Conversely, exercise was effective in restoring most of these values to levels approximating the control group, indicating a potential protective effect of regular exercise against the detrimental impacts of high sucrose dietary consumption on the hypothalamus.

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Environmental changes can trigger endoplasmic reticulum (ER) stress and misfolded protein accumulation, potentially leading to pre-eclampsia (PE). Amyloid-β (Aβ) is a crucial misfolded protein that can overactivate autophagy. Our study assessed the expression of Aβ₁₋₄₂ and autophagic activity in PE placental tissues and trophoblasts under ER stress. Placental tissues were surgically collected from normal pregnant women (NP) and pregnant women with late-onset PE (LOPE) delivering through cesarean section. The expression levels of Aβ₁₋₄₂ were detected in both PE and NP placental tissues, as well as in tunicamycin (TM)-induced HTR-8/SVneo cells. Autophagy-related proteins, such as Beclin-1, the ratio of LC3-II to LC3-I, ATG5, and SQSTM1/p62 in the placental tissues and HTR-8/SVneo cells were measured by Western blot. The number and morphology of autophagosomes were observed using transmission electron microscopy (TEM). Potential targets associated with the unfolded protein response (UPR) in the placental tissues of NP and PE cases were screened using PCR Arrays. The misfolded protein was significantly upregulated in the PE group. In both PE placental tissues and TM-induced HTR-8/SVneo cells, not only was Aβ₁₋₄₂ upregulated, but also Beclin-1, ATG5, and LC3BII/I were significantly increased, accompanied by an increase in autophagosome count, while SQSTM1/P62 was downregulated. A total of 17 differentially expressed genes (DEGs) associated with the UPR were identified, among which elevated calnexin (CANX) was validated in the placenta from both PE and TM-induced HTR-8/SVneo cells. Autophagy is significantly upregulated in PE cases due to ER stress-induced Aβ₁₋₄₂ accumulation, likely mediated by autophagy-related proteins involved in the UPR.