Acta histochemica最新文献

Objective: Psoriasis is a chronic inflammatory skin disease characterized by excessive proliferation and abnormal differentiation of keratinocytes. Although stem cell-based therapies have shown promise in treating psoriasis, the underlying mechanisms remain unclear. This study aimed to established a psoriatic cell model to investigate the effect of normal dermal mesenchymal stem cell (DMSCs) on keratinocyte proliferation, inflammation responses and the associated mechanism.

Methods: To create an in vitro model of psoriasis, HaCaT cells were stimulated with a mixture of five inflammatory cytokines including IL-17A, IL-22, oncostatin M, IL-1α, and TNF-α (M5). A transwell co-culture system was employed to assess the influence of normal DMSCs on proliferation and inflammation response of HaCaT cells. Cell viability was assessed using the CCK-8 assay and EDU incorporation assay. The expression levels of mRNA for inflammatory cytokines (IL-8, IL-17A and TNF-α) in HaCaT cells co-cultured with either normal or psoriatic DMSCs were quantified by qRT-PCR. Apoptosis was evaluated by annexin V-FITC/PI double staining and TUNEL/DAPI staining assay. Autophagy was detected by immunostaining, RT-PCR and western blotting. Additionally, the expression levels of mRNA and protein of both Akt and mammalin target of rapamycin(mTOR) were also determined.

Results: Normal DMSCs were found to decrease the viability and promote apoptosis of HaCaT cells treated with M5. Furthermore, DMSCs reduced the secretion of proinflammatory cytokines, such as IL-8, IL-17A and TNF-α. Importantly, normal DMSCs were shown to induced autophagy in HaCaT cell. Pretreatment of HaCaT cells with autophagy inhibitor 3-methyladenine (3-MA) reversed the anti-psoriatic effect of normal DMSCs. Notably, DMSCs promote autophagy in M5-treated HaCaT cells by inhibition of p-Akt/Akt and p-mTOR/mTOR ratio.

Conclusion: Normal mesenchymal stem cells promote autophagy through the inhibition of Akt/mTOR signaling pathway, leading to the alleviation of psoriasis in vitro. These findings provide insights into the potential mechanisms by which DMSCs may exert therapeutic effects in psoriasis and support further investigation into their clinical applications.

Background: Cervical cancer is a major health burden in females worldwide, available studies indicated that sex-determining region Y-box 2 (SOX2) is closely related to the malignant phenotypes of multiple cancers including cervical cancer. However, the underlying mechanisms were blurred.

Experimental procedures: A bioinformatics analysis was conducted to investigate the clinical correlation between SOX2 and cervical cancer. Transient transfection and lentivirus infection were utilized to achieve overexpression and knockdown of SOX2, respectively. The role of SOX2 in cervical cancer was confirmed by transwell and colony-forming assays. Immunoblot, dual-luciferase reporter, chromatin immunoprecipitation (ChIP), and biochemical experiments were employed. In addition, the xenograft models and immunohistochemistry (IHC) experiments were performed to validate the findings in vivo.

Results: The expression of SOX2 was significantly positively associated with the cell migration, invasion, and colony-forming abilities of cervical cancer cells. The following immunoblots revealed that the SOX2-induced malignant phenotypes might be related to the glycolysis process, since overexpressing SOX2 significantly promoted the hexokinase 2 (HK2) and glucose transporter-1 (GLUT1) expression, and increased the content of glucose and lactic acid. The further dual-luciferase reporter and ChIP experiments confirmed a binding relationship between SOX2 and HK2 promoter. More importantly, overexpressing SOX2 promoted tumor growth concomitant with a hyper-expression of HK2 and GLUT1 in xenograft tumor tissues, yet the treatment of glycolysis inhibitor significantly reversed those outcomes.

Conclusion: SOX2 promotes the malignant progression of cervical cancer by facilitating glycolysis.

In recent years, a great interest has been focused on the prebiotic origin of nucleic acids and life on Earth. An attractive idea is that life was initially based on an autocatalytic and autoreplicative RNA (the RNA-world). RNA duplexes are right-handed helical chains with antiparallel orientation, but the rationale for these features is not yet known. An antiparallel (inverted) stacking of purine nucleosides was reported in crystallographic studies. Molecular modeling also supports the inverted orientation of nucleosides. This preferential stacking can also appear when nucleosides are included in a montmorillonite clay matrix. Free-energy values and geometrical parameters show that D-ribose chirality is preferred for the formation of right-handed RNA molecules. Thus, a "zipper" model with antiparallel and auto-intercalated nucleosides linked by phosphate groups can be proposed to form single RNA chains. Unstacking with strand separation and base pairing by H-bonding, results in shortening and inclination of ribose-phosphate chains, leading to right-handed helicity and antiparallel duplexes. Incorporation of complementary precursors on the major groove template by a self-assembly mechanism provides a prebiotic (non-enzymatic) "tetris" replication model by formation of a transient RNA tetrad and tetraplex. Original hairpin motifs appear as simple building units that form typical RNA structures such as hammerheads, cloverleaves and dumbbells. They occur today in the circular viroids and virusoids, as well as in highly branched and complex rRNA molecules.

Hyperplasia of microvessels in the superficial dermis is the main pathological feature of psoriasis, and is linked to the pathogenesis of psoriasis. Thus, anti-angiogenic therapy may be effective for psoriasis. Angiopoietins (Angs) are crucial angiogenic factors. Ang1 supports a static mature vascular phenotype, while Ang2 is associated with the formation of abnormal vascular structure, vascular leakage and inflammation. The Ang/Tie2 axis and its signal transduction play an important role in regulation of vascular stability, angiogenesis and inflammation. Targeting the Ang/Tie2 signal axis can normalize microvessels in psoriatic lesions. This paper reviews Ang/Tie2 signal axis and its role in angiogenesis of psoriasis, aiming to provide new ideas and strategies for anti-angiogenic therapy of psoriasis.

Many fluorophores display interesting features that make them useful biological labels and dyes, particularly in Cell Biology and Cytogenetics. Changes in the absorption-emission spectra (ortho- and metachromasia) are accounted among them. Acridine orange (AO) is one of such fluorochromes with an exemplary orthochromatic vs. metachromatic emission, which depends on its concentration and binding mode to different cell substrates. Here, we revisit the differential AO fluorescence that occurs in selected biological materials, which allows the identification of single-stranded or double-stranded nucleic acids. Although known for a long time, the ultimate reason for this differential phenomenon has not been properly addressed. We propose a potential molecular mechanism that adequately accounts for the distinct AO emission when bound either to denatured or denatured-reassociated DNA. This mechanism, based on theoretical molecular modelling, implies a difference in the degree of overlap of excited state orbitals whenever AO molecules are interacting with bases from single- or double-stranded nucleic acids. In the first case, massive orbital overlapping leads to a metachromatic red AO emission. Otherwise, no excited-state orbital overlapping occurs, due to excessive distance between intercalated AO molecules, which manifests as orthochromatic green fluorescence. Our molecular modelling supports this interplay between orbital overlap/not overlap and metachromatic/orthochromatic fluorescence.

Despite of decades of efforts, novel approaches are still limited to attenuate or prevent skin scarring. A previous report published in Science demonstrated that inhibition of YAP promotes scarless wound repair by regeneration. Due to the difficult drugability of targeting YAP, we speculated that inhibition of TEAD, a partner molecule of YAP, might exist similar therapeutic potential. Therefore, the aim of the study was to evaluate therapeutical effect of a novel inhibitor of TEAD auto-palmitoylation, VT107, on scar formation in a cutaneous wound healing model. Our findings confirmed VT107 exhibited favorable effect on preventing scarring, manifesting as reducing fibroblast proliferation and collagen denaturation, decreasing TGF-β1 and collagen deposition, as well as connective tissue growth factor (CTGF) expression. These findings provide a novel insight for the development of anti-scarring strategies. TEAD would become an ideal target for the treatment of scars.

Autophagy plays an important role in the physiology and pathology of the liver. Several negative autophagy regulators have been discovered, including epidermal growth factor receptor (EGFR), mediated by activation of the PI3K/Akt/mTOR signaling pathway. Disabled-1 (Dab1) is one of the mediating adaptor factors of PI3K/Akt/mTOR signaling pathways. We investigated the potential impact of Dab1 on autophagy-related markers (LC3B, LAMP2A, HSC70, and GRP78) in the developing liver by using a model of yotari mice and compared it with autophagy marker expression in human liver development. Mouse embryos were obtained at gestation days 13.5 and 15.5 (E13.5 and E15.5), and a total of 5 normal human conceptuses were obtained between gestation days 5 and 10. Histological sections were analyzed by immunohistochemistry. The highest expression of the early endosome-forming factor LC3B and the microautophagy factor LAMP2a was observed at the transition from embryonic to early fetal phase, whereas the expression of the chaperones HSC 70 and GRP78 was highest at embryonic phase. The expression patterns of three of these factors in mouse liver were different from those in human liver: the expression of LC3B was high at E13.5, that of HSC 70 at 15.5, whereas the expression of GRP78 did not change significantly. On the other hand, the expression pattern of LAMP2a was similar to that in human development and was higher at E15.5 than at E13.5. Moreover, knockout of Dab1 resulted in significantly lower expression of LC3B and LAMP2a in mouse embryo livers (at E13.5), indicating a possible role of Dab1 in regulating autophagy during embryonic development in the liver.

Vascular endothelial cells (VECs) play a crucial role in the development and maintenance of vascular biology specific to the tissue types. Molecular signature-based labeling and imaging of VECs help researchers understand potential mechanisms linking VECs to disease pathology, serving as valuable biomarkers in clinical settings and trials. Labeling techniques involve selectively tagging or marking VECs for visualization. Immunolabeled employs antibodies that specifically bind to VECs markers, while fluorescent tracers or dyes can directly label VECs for imaging. Some techniques use specific carbohydrate residues on cell surface, while others employ endothelial-specific promoters to express fluorescent proteins. Additionally, VEC can be labeled with contrast agents, radiolabeled tracers, and nanoparticles. The choice of labeling technique depends on study context, including whether it involves animal models, in vitro cell cultures, or clinical applications. Herein, we discussed the various labeling methods utilized to label VECs and the techniques to visualize them.