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Journal of Biomedical Research Apr 2024The retinal pigment epithelium (RPE) is fundamental to sustaining retinal homeostasis. RPE abnormality leads to visual defects and blindness, including age-related...
The retinal pigment epithelium (RPE) is fundamental to sustaining retinal homeostasis. RPE abnormality leads to visual defects and blindness, including age-related macular degeneration (AMD). Although breakthroughs have been made in the treatment of neovascular AMD, effective intervention for atrophic AMD is largely absent. The inadequate knowledge of RPE pathology is hindered by a lack of patient RPE datasets, especially at the single-cell resolution. In this study, we delved into a large-scale single-cell resource of AMD donors in which RPE cells were occupied in a substantial proportion. Bulk RNA-seq datasets of atrophic AMD were integrated to extract molecular characteristics of RPE in the pathogenesis of atrophic AMD. Both and models revealed that carboxypeptidase X, M14 family member 2 (CPXM2) was specifically expressed in the RPE cells of atrophic AMD, which might be induced by oxidative stress and involved in the epithelial-mesenchymal transition of RPE cells. Additionally, silencing of inhibited the mesenchymal phenotype of RPE cells in an oxidative stress cell model. Thus, our results demonstrate that CPXM2 plays a crucial role in regulating atrophic AMD and may serve as a potential therapeutic target for atrophic AMD.
PubMed: 38808557
DOI: 10.7555/JBR.37.20230320 -
Heliyon May 2024The SARS-CoV-2 pandemic has highlighted the need for broad-spectrum antiviral drugs to respond promptly to viral emergence. We conducted a preclinical study of...
The SARS-CoV-2 pandemic has highlighted the need for broad-spectrum antiviral drugs to respond promptly to viral emergence. We conducted a preclinical study of molnupiravir (MOV) against SARS-CoV-2 to fully characterise its antiviral properties and mode of action. The antiviral activity of different concentrations of MOV was evaluated on human airway epithelium (HAE) and in a hamster model at three escalating doses (150, 300 and 400 mg/kg/day) according to three different regimens (preventive, pre-emptive and curative). We assessed viral loads and infectious titres at the apical pole of HAE and in hamster lungs, and MOV trough concentration in plasma and lungs. To explore the mode of action of the MOV, the entire genomes of the collected viruses were deep-sequenced. MOV effectively reduced viral titres in HAE and in the lungs of treated animals. Early treatment after infection was a key factor in efficacy, probably associated with high lung concentrations of MOV, suggesting good accumulation in the lung. MOV induced genomic alteration in viral genomes with an increase in the number of minority variants, and predominant G to A transitions. The observed reduction in viral replication and its mechanism of action leading to lethal mutagenesis, supported by clinical trials showing antiviral action in humans, provide a convincing basis for further research as an additional means in the fight against COVID-19 and other RNA viruses.
PubMed: 38803975
DOI: 10.1016/j.heliyon.2024.e30862 -
Frontiers in Oncology 2024MicroRNA-875-5p (miR-875-5p) is a cancer-related microRNA. It has been demonstrated that miR-875-5p participates in the development of various types of cancer such as...
INTRODUCTION
MicroRNA-875-5p (miR-875-5p) is a cancer-related microRNA. It has been demonstrated that miR-875-5p participates in the development of various types of cancer such as hepatocellular carcinoma, gastric carcinoma, prostate and bladder cancer. Previous research suggested that miR-875 is implicated in the development of cervical cancer cells. However, the exact role and function of miR-875-5p in cervical cancer remain unexplored. It is important to examine the role and function of miR-875-5p and the associated signaling pathway, as the findings may have diagnostic and therapeutic significance. Thus, in this study, we investigated the effect of miR-875-5p on the growth and metastasis of cervical cancer cells and the possible underlying mechanisms.
METHODS
Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression of miR-875-5p in cervical cancer cells and normal cervical epithelium. After overexpression or co-expression of miR-875-5p in cells, the changes in cell function were analyzed. Western blot was used to detect the expression changes of epithelial-mesenchymal transition (EMT) -related proteins and autophagy-related proteins.
RESULTS
Functional studies demonstrated that miR-875-5p overexpression significantly inhibited the proliferation, migration, invasion, and EMT, and promotes apoptosis and autophagy of cervical cancer cells., while miR-875-5p knockdown promoted the proliferation, migration, invasion, and EMT, and inhibited apoptosis and autophagy cervical cancer cells. Furthermore, Western blot results showed that overexpression of miR-875-5p downregulated the expressions of N-cadherin, Snail, Vimentin and microtubule-associated protein 1 light chain 3B I (LC3B I). Conversely, miR-875-5p upregulated the expression of E-cadherin.
CONCLUSION
In conclusion, our findings suggest that miR-875-5p functions as a tumor inhibitor suppressing the growth and metastasis of cervical cancer. Overexpression of miR-875-5p inhibits malignant behavior and promotes autophagy and apoptosis in cervical cancer cells. These findings advance our understanding of the role and function of miR-875-5p in cervical cancer and could facilitate the development of early genetic markers or biomarkers and therapeutic targets for cervical cancer.
PubMed: 38800376
DOI: 10.3389/fonc.2024.1361721 -
Medicina (Kaunas, Lithuania) Apr 2024: Despite the fact that biologic drugs have transformed inflammatory bowel disease (IBD) treatment, addressing fibrosis-related strictures remains a research gap. This...
: Despite the fact that biologic drugs have transformed inflammatory bowel disease (IBD) treatment, addressing fibrosis-related strictures remains a research gap. This study explored the roles of cytokines, macrophages, and Krüppel-like factors (KLFs), specifically KLF4, in intestinal fibrosis, as well as the interplay of KLF4 with various gut components. : This study examined macrophage subtypes, their KLF4 expression, and the effects of knockdown on macrophage polarization and cytokine expression using THP-1 monocyte models. Co-culture experiments with stromal myofibroblasts and a conditioned medium from macrophage subtype cultures were conducted to study the role of these cells in intestinal fibrosis. Human-induced pluripotent stem cell-derived small intestinal organoids were used to confirm inflammatory and fibrotic responses in the human small intestinal epithelium. : Each macrophage subtype exhibited distinct phenotypes and KLF4 expression. Knockdown of induced inflammatory cytokine expression in M0, M2a, and M2c cells. M2b exerted anti-fibrotic effects via interleukin (IL)-10. M0 and M2b cells showed a high migratory capacity toward activated stromal myofibroblasts. M0 cells interacting with activated stromal myofibroblasts transformed into inflammatory macrophages, thereby increasing pro-inflammatory cytokine expression. The expression of , linked to fibrosis, was upregulated. : This study elucidated the role of KLF4 in macrophage polarization and the intricate interactions between macrophages, stromal myofibroblasts, and cytokines in experimental in vitro models of intestinal fibrosis. The obtained results may suggest the mechanism of fibrosis formation in clinical IBD.
Topics: Kruppel-Like Factor 4; Humans; Fibrosis; Macrophages; Kruppel-Like Transcription Factors; Monocytes; Phenotype; Inflammatory Bowel Diseases; Cytokines; THP-1 Cells
PubMed: 38792896
DOI: 10.3390/medicina60050713 -
Molecular Biology and Evolution Jun 2024Transglutaminases (TGMs) cross-link proteins by introducing covalent bonds between glutamine and lysine residues. These cross-links are essential for epithelial...
Transglutaminases (TGMs) cross-link proteins by introducing covalent bonds between glutamine and lysine residues. These cross-links are essential for epithelial cornification which enables tetrapods to live on land. Here, we investigated which evolutionary adaptations of vertebrates were associated with specific changes in the family of TGM genes. We determined the catalog of TGMs in the main clades of vertebrates, performed a comprehensive phylogenetic analysis of TGMs, and localized the distribution of selected TGMs in tissues. Our data suggest that TGM1 is the phylogenetically oldest epithelial TGM, with orthologs being expressed in the cornified teeth of the lamprey, a basal vertebrate. Gene duplications led to the origin of TGM10 in stem vertebrates, the origin of TGM2 in jawed vertebrates, and an increasing number of epithelium-associated TGM genes in the lineage leading to terrestrial vertebrates. TGM9 is expressed in the epithelial egg tooth, and its evolutionary origin in stem amniotes coincided with the evolution of embryonic development in eggs that are surrounded by a protective shell. Conversely, viviparous mammals have lost both the epithelial egg tooth and TGM9. TGM3 and TGM6 evolved as regulators of cornification in hair follicles and underwent pseudogenization upon the evolutionary loss of hair in cetaceans. Taken together, this study reveals the gain and loss of vertebrate TGM genes in association with the evolution of cornified skin appendages and suggests an important role of TGM9 in the evolution of amniotes.
Topics: Animals; Transglutaminases; Vertebrates; Evolution, Molecular; Phylogeny; Biological Evolution; Skin
PubMed: 38781495
DOI: 10.1093/molbev/msae100 -
Nature Communications May 2024Fossil feathers have transformed our understanding of integumentary evolution in vertebrates. The evolution of feathers is associated with novel skin ultrastructures,...
Fossil feathers have transformed our understanding of integumentary evolution in vertebrates. The evolution of feathers is associated with novel skin ultrastructures, but the fossil record of these changes is poor and thus the critical transition from scaled to feathered skin is poorly understood. Here we shed light on this issue using preserved skin in the non-avian feathered dinosaur Psittacosaurus. Skin in the non-feathered, scaled torso is three-dimensionally replicated in silica and preserves epidermal layers, corneocytes and melanosomes. The morphology of the preserved stratum corneum is consistent with an original composition rich in corneous beta proteins, rather than (alpha-) keratins as in the feathered skin of birds. The stratum corneum is relatively thin in the ventral torso compared to extant quadrupedal reptiles, reflecting a reduced demand for mechanical protection in an elevated bipedal stance. The distribution of the melanosomes in the fossil skin is consistent with melanin-based colouration in extant crocodilians. Collectively, the fossil evidence supports partitioning of skin development in Psittacosaurus: a reptile-type condition in non-feathered regions and an avian-like condition in feathered regions. Retention of reptile-type skin in non-feathered regions would have ensured essential skin functions during the early, experimental stages of feather evolution.
Topics: Animals; Feathers; Dinosaurs; Fossils; Biological Evolution; Skin; Reptiles; Melanosomes; Animal Scales; Epidermis; beta-Keratins
PubMed: 38773066
DOI: 10.1038/s41467-024-48400-3 -
Cellular and Molecular Life Sciences :... May 2024Ischemic stroke induces neovascularization of the injured tissue as an attempt to promote structural repair and neurological recovery. Angiogenesis is regulated by...
Ischemic stroke induces neovascularization of the injured tissue as an attempt to promote structural repair and neurological recovery. Angiogenesis is regulated by pericytes that potently react to ischemic stroke stressors, ranging from death to dysfunction. Platelet-derived growth factor (PDGF) receptor (PDGFR)β controls pericyte survival, migration, and interaction with brain endothelial cells. PDGF-D a specific ligand of PDGFRβ is expressed in the brain, yet its regulation and role in ischemic stroke pathobiology remains unexplored. Using experimental ischemic stroke mouse model, we found that PDGF-D is transiently induced in brain endothelial cells at the injury site in the subacute phase. To investigate the biological significance of PDGF-D post-ischemic stroke regulation, its subacute expression was either downregulated using siRNA or upregulated using an active recombinant form. Attenuation of PDGF-D subacute induction exacerbates neuronal loss, impairs microvascular density, alters vascular permeability, and increases microvascular stalling. Increasing PDGF-D subacute bioavailability rescues neuronal survival and improves neurological recovery. PDGF-D subacute enhanced bioavailability promotes stable neovascularization of the injured tissue and improves brain perfusion. Notably, PDGF-D enhanced bioavailability improves pericyte association with brain endothelial cells. Cell-based assays using human brain pericyte and brain endothelial cells exposed to ischemia-like conditions were applied to investigate the underlying mechanisms. PDGF-D stimulation attenuates pericyte loss and fibrotic transition, while increasing the secretion of pro-angiogenic and vascular protective factors. Moreover, PDGF-D stimulates pericyte migration required for optimal endothelial coverage and promotes angiogenesis. Our study unravels new insights into PDGF-D contribution to neurovascular protection after ischemic stroke by rescuing the functions of pericytes.
Topics: Pericytes; Animals; Ischemic Stroke; Mice; Lymphokines; Platelet-Derived Growth Factor; Humans; Endothelial Cells; Male; Mice, Inbred C57BL; Brain; Disease Models, Animal; Neovascularization, Physiologic; Cell Movement
PubMed: 38769116
DOI: 10.1007/s00018-024-05244-w -
PloS One 2024Candida albicans (C. albicans) can behave as a commensal yeast colonizing the vaginal mucosa, and in this condition is tolerated by the epithelium. When the epithelial...
Candida albicans (C. albicans) can behave as a commensal yeast colonizing the vaginal mucosa, and in this condition is tolerated by the epithelium. When the epithelial tolerance breaks down, due to C. albicans overgrowth and hyphae formation, the generated inflammatory response and cell damage lead to vulvovaginal candidiasis (VVC) symptoms. Here, we focused on the induction of mitochondrial reactive oxygen species (mtROS) in vaginal epithelial cells after C. albicans infection and the involvement of fungal burden, morphogenesis and candidalysin (CL) production in such induction. Bioluminescent (BLI) C. albicans, C. albicans PCA-2 and C. albicans 529L strains were employed in an in vitro infection model including reconstituted vaginal epithelium cells (RVE), produced starting from A-431 cell line. The production of mtROS was kinetically measured by using MitoSOX™ Red probe. The potency of C. albicans to induced cell damage to RVE and C. albicans proliferation have also been evaluated. C. albicans induces a rapid mtROS release from vaginal epithelial cells, in parallel with an increase of the fungal load and hyphal formation. Under the same experimental conditions, the 529L C. albicans strain, known to be defective in CL production, induced a minor mtROS release showing the key role of CL in causing epithelial mithocondrial activation. C. albicans PCA-2, unable to form hyphae, induced comparable but slower mtROS production as compared to BLI C. albicans yeasts. By reducing mtROS through a ROS scavenger, an increased fungal burden was observed during RVE infection but not in fungal cultures grown on abiotic surface. Collectively, we conclude that CL, more than fungal load and hyphae formation, seems to play a key role in the rapid activation of mtROS by epithelial cells and in the induction of cell-damage and that mtROS are key elements in the vaginal epithelial cells response to C. albicans.
Topics: Candida albicans; Female; Humans; Mitochondria; Vagina; Reactive Oxygen Species; Epithelial Cells; Fungal Proteins; Candidiasis, Vulvovaginal; Hyphae; Cell Line
PubMed: 38768097
DOI: 10.1371/journal.pone.0303449 -
Cell Reports May 2024Terminal differentiation requires massive restructuring of the transcriptome. During intestinal differentiation, the expression patterns of nearly 4,000 genes are...
Terminal differentiation requires massive restructuring of the transcriptome. During intestinal differentiation, the expression patterns of nearly 4,000 genes are altered as cells transition from progenitor cells in crypts to differentiated cells in villi. We identify dynamic occupancy of RNA polymerase II (Pol II) to gene promoters as the primary driver of transcriptomic shifts during intestinal differentiation in vivo. Changes in enhancer-promoter looping interactions accompany dynamic Pol II occupancy and are dependent upon HNF4, a pro-differentiation transcription factor. Using genetic loss-of-function, chromatin immunoprecipitation sequencing (ChIP-seq), and immunoprecipitation (IP) mass spectrometry, we demonstrate that HNF4 collaborates with chromatin remodelers and loop-stabilizing proteins and facilitates Pol II occupancy at hundreds of genes pivotal to differentiation. We also explore alternate mechanisms that drive differentiation gene expression and find that pause-release of Pol II and post-transcriptional mRNA stability regulate smaller subsets of differentially expressed genes. These studies provide insights into the mechanisms of differentiation in renewing adult tissue.
PubMed: 38768033
DOI: 10.1016/j.celrep.2024.114242 -
International Journal of Ophthalmology 2024To explore the effects of hepatocyte growth factor (HGF) on retinal pigment epithelium (RPE) cell behaviors.
AIM
To explore the effects of hepatocyte growth factor (HGF) on retinal pigment epithelium (RPE) cell behaviors.
METHODS
The human adult retinal pigment epithelial cell line-19 (ARPE-19) were treated by HGF or mesenchymal-epithelial transition factor (MET) inhibitor SU11274 . Cell viability was detected by a Cell Counting Kit-8 assay. Cell proliferation and motility was detected by a bromodeoxyuridine incorporation assay and a wound healing assay, respectively. The expression levels of MET, phosphorylated MET, protein kinase B (AKT), and phosphorylated AKT proteins were determined by Western blot assay. The MET and phosphorylated MET proteins were also determined by immunofluorescence assay.
RESULTS
HGF increased ARPE-19 cells' viability, proliferation and migration, and induced an increase of phosphorylated MET and phosphorylated AKT proteins. SU11274 significantly reduced cell viability, proliferation, and migration and decreased the expression of MET and AKT proteins. SU11274 suppressed HGF-induced increase of viability, proliferation, and migration in ARPE-19 cells. Additionally, SU11274 also blocked HGF-induced phosphorylation of MET and AKT proteins.
CONCLUSION
HGF enhances cellular viability, proliferation, and migration in RPE cells through the MET/AKT signaling pathway, whereas this enhancement is suppressed by the MET inhibitor SU11274. HGF-induced MET/AKT signaling might be a vital contributor of RPE cells survival.
PubMed: 38766346
DOI: 10.18240/ijo.2024.05.03