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Cell Death & Disease Jun 2020Mitochondrial dysfunction leads to osteoarthritis (OA) and disc degeneration. Hypoxia inducible factor-1α (HIF-1α) mediated mitophagy has a protective role in several...
Mitochondrial dysfunction leads to osteoarthritis (OA) and disc degeneration. Hypoxia inducible factor-1α (HIF-1α) mediated mitophagy has a protective role in several diseases. However, the underlying mechanism of HIF-1α mediated mitophagy in OA remains largely unknown. This current study was performed to determine the effect of HIF-1α mediated mitophagy on OA. Therefore, X-ray and tissue staining including HE staining, safranin O-fast green (S-O) and Alcian Blue were used to assess imageology and histomorphology differences of mouse knee joint. Transcriptional analysis was used to find the possible targets in osteoarthritis. Western blot analysis, RT-qPCR and immunofluorescence staining were used to detect the changes in gene and protein levels in the vitro experiment. The expression of HIF-1α was increased in human and mouse OA cartilage. HIF-1α knockdown by siRNA further impair the hypoxia-induced mitochondrial dysfunction; In contrast, HIF-1α mediated protective role was reinforced by prolylhydroxylase (PHD) inhibitor dimethyloxalylglycine (DMOG). In addition, HIF-1α stabilization could alleviate apoptosis and senescence via mitophagy in chondrocytes under hypoxia condition, which could also ameliorate surgery-induced cartilage degradation in mice OA model. In conclusion, HIF-1α mediated mitophagy could alleviate OA, which may serve as a promising strategy for OA treatment.
Topics: Amino Acids, Dicarboxylic; Animals; Apoptosis; Autophagy; Cartilage, Articular; Cell Hypoxia; Cellular Senescence; Chondrocytes; Cytoprotection; Disease Models, Animal; Extracellular Matrix; Female; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Male; Meniscus; Mice, Inbred C57BL; Middle Aged; Mitochondria; Mitophagy; Osteoarthritis; Protein Stability; Reactive Oxygen Species
PubMed: 32587244
DOI: 10.1038/s41419-020-2680-0 -
Microbiome Oct 2020"Western" style dietary patterns are characterized by a high proportion of highly processed foods rich in fat and low in fiber. This diet pattern is associated with a...
BACKGROUND
"Western" style dietary patterns are characterized by a high proportion of highly processed foods rich in fat and low in fiber. This diet pattern is associated with a myriad of metabolic dysfunctions, including neuroinflammation and cognitive impairment. β-glucan, the major soluble fiber in oat and barley grains, is fermented in the lower gastrointestinal tract, potentially impacting the microbial ecosystem and thus may improve elements of cognition and brain function via the gut-brain axis. The present study aimed to evaluate the effect of β-glucan on the microbiota gut-brain axis and cognitive function in an obese mouse model induced by a high-fat and fiber-deficient diet (HFFD).
RESULTS
After long-term supplementation for 15 weeks, β-glucan prevented HFFD-induced cognitive impairment assessed behaviorally by object location, novel object recognition, and nesting building tests. In the hippocampus, β-glucan countered the HFFD-induced microglia activation and its engulfment of synaptic puncta, and upregulation of proinflammatory cytokine (TNF-α, IL-1β, and IL-6) mRNA expression. Also, in the hippocampus, β-glucan significantly promoted PTP1B-IRS-pAKT-pGSK3β-pTau signaling for synaptogenesis, improved the synaptic ultrastructure examined by transmission electron microscopy, and increased both pre- and postsynaptic protein levels compared to the HFFD-treated group. In the colon, β-glucan reversed HFFD-induced gut barrier dysfunction increased the thickness of colonic mucus (Alcian blue and mucin-2 glycoprotein immunofluorescence staining), increased the levels of tight junction proteins occludin and zonula occludens-1, and attenuated bacterial endotoxin translocation. The HFFD resulted in microbiota alteration, effects abrogated by long-term β-glucan supplementation, with the β-glucan effects on Bacteroidetes and its lower taxa particularly striking. Importantly, the study of short-term β-glucan supplementation for 7 days demonstrated pronounced, rapid differentiating microbiota changes before the cognitive improvement, suggesting the possible causality of gut microbiota profile on cognition. In support, broad-spectrum antibiotic intervention abrogated β-glucan's effects on improving cognition, highlighting the role of gut microbiota to mediate cognitive behavior.
CONCLUSION
This study provides the first evidence that β-glucan improves indices of cognition and brain function with major beneficial effects all along the gut microbiota-brain axis. Our data suggest that elevating consumption of β-glucan-rich foods is an easily implementable nutritional strategy to alleviate detrimental features of gut-brain dysregulation and prevent neurodegenerative diseases associated with Westernized dietary patterns. Video Abstract.
Topics: Animals; Brain; Cognitive Dysfunction; Diet, High-Fat; Dietary Fiber; Gastrointestinal Microbiome; Male; Mice; Mice, Inbred C57BL; Obesity; beta-Glucans
PubMed: 33008466
DOI: 10.1186/s40168-020-00920-y -
Phytomedicine : International Journal... Mar 2023Current therapeutics for ulcerative colitis (UC) have limitations. Classical Formula Gegen Qinlian decoction (GQD) is derived from Shang Han Lun and has a long history...
BACKGROUND
Current therapeutics for ulcerative colitis (UC) have limitations. Classical Formula Gegen Qinlian decoction (GQD) is derived from Shang Han Lun and has a long history of treating gastrointestinal diseases such as diarrhea and UC. Nevertheless, the exact mechanism of it needs to be further clarified.
PURPOSE
We aimed to investigate the treatment effects of modified GQD (MGQD) on dextran sodium sulfate (DSS)-induced chronic colitis in mice and conduct further exploration of its underlying mechanisms.
METHODS
The protective effect of MGQD was estimated in a DSS-induced chronic colitis mouse model. Model evaluation included body weight, disease activity index (DAI) score, colon length and histopathology. Alcian Blue/Phosphoric Acid Schiff (AB/PAS) staining, transmission electron microscopy (TEM), immunofluorescence and real time‒PCR (RT-PCR) were used to assess goblet cell function. ELISA, flow cytometry and immunofluorescence were applied to estimate the immunoinflammatory status. Western blot was performed to test the protein expression levels of relevant pathways and related receptors. All experiments were conducted in duplicate.
RESULTS
MGQD alleviated DSS‑induced chronic colitis symptoms in mice, protected goblet cell function and restored the intestinal mucus barrier. Furthermore, MGQD efficiently suppressed the abnormal immune inflammatory response and the activate of γδT17 cells and NLRP3 inflammasome.
CONCLUSION
The mechanisms by which MGQD protects against DSS-induced chronic colitis may involve restoring goblet cell function, repairing the intestinal mucus barrier, and modulating the immune inflammatory response. More importantly, MGQD inhibited NLRP3 inflammasome-associated signaling pathway activation, which consequently reduced the activation of γδT17 cells.
Topics: Animals; Mice; Colitis; Colitis, Ulcerative; Colon; Dextran Sulfate; Disease Models, Animal; Inflammasomes; Mice, Inbred C57BL; Mucus; NLR Family, Pyrin Domain-Containing 3 Protein
PubMed: 36681051
DOI: 10.1016/j.phymed.2023.154660 -
Aging Nov 2019The inflammatory-associated factors interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) are widely reported to be associated with...
The inflammatory-associated factors interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) are widely reported to be associated with intervertebral disc (IVD) degeneration (IVDD). N-acetyl-5-methoxytryptamine (melatonin) is a natural hormone secreted by the pineal gland which has been shown to participate in several physiological and pathological progresses, such as aging, anti-inflammation, anti-apoptosis and autophagy regulation. However, the effects of melatonin on IVD remain unclear. In the present study, we treated human nucleus pulposus cells (NPCs) with melatonin and discovered that melatonin could modulate extracellular matrix (ECM) remodeling induced by IL-1β by enhancing collagen II and aggrecan expression levels and by downregulating matrix metalloproteinase-3 (MMP-3) levels. These findings were verified by western blot and immunofluorescence assays. Intraperitoneal injection of melatonin mitigated IVDD in the rat tail puncture model. X-ray and magnetic resonance imaging (MRI), as well as hematoxylin-eosin (H&E), Safranine O-Green, Alcian blue and Celium red staining methods were adopted to evaluate IVDD grades, the structural integrity of nucleus pulposus (NP) and annulus fibrosus (AF) and the damage and calcification of the cartilage endplate. Melatonin reduced inflammatory cell aggregation and the release of the inflammatory factors IL-1β, IL-6, TNF-α as determined by immunohistochemistry. In conclusion, the present study demonstrated that melatonin could modulate ECM remodeling by IL-1β in vitro and attenuate the IVDD and induction of inflammation in a rat tail puncture model in vivo. The data demonstrated that melatonin may contribute to the restoration processs of IVD following damage and may be used as a potential novel therapy for IVDD.
Topics: Animals; Extracellular Matrix; Female; Humans; Inflammation; Interleukin-1beta; Intervertebral Disc Degeneration; Melatonin; Nucleus Pulposus; Rats; Rats, Sprague-Dawley
PubMed: 31772145
DOI: 10.18632/aging.102472 -
ELife May 2022Proliferating cells undergo metabolic changes in synchrony with cell cycle progression and cell division. Mitochondria provide fuel, metabolites, and ATP during...
Proliferating cells undergo metabolic changes in synchrony with cell cycle progression and cell division. Mitochondria provide fuel, metabolites, and ATP during different phases of the cell cycle, however it is not completely understood how mitochondrial function and the cell cycle are coordinated. CLUH (clustered mitochondria homolog) is a post-transcriptional regulator of mRNAs encoding mitochondrial proteins involved in oxidative phosphorylation and several metabolic pathways. Here, we show a role of CLUH in regulating the expression of astrin, which is involved in metaphase to anaphase progression, centrosome integrity, and mTORC1 inhibition. We find that CLUH binds both the mRNA and its product astrin, and controls the synthesis and the stability of the full-length astrin-1 isoform. We show that CLUH interacts with astrin-1 specifically during interphase. Astrin-depleted cells show mTORC1 hyperactivation and enhanced anabolism. On the other hand, cells lacking CLUH show decreased astrin levels and increased mTORC1 signaling, but cannot sustain anaplerotic and anabolic pathways. In absence of CLUH, cells fail to grow during G1, and progress faster through the cell cycle, indicating dysregulated matching of growth, metabolism, and cell cycling. Our data reveal a role of CLUH in coupling growth signaling pathways and mitochondrial metabolism with cell cycle progression.
Topics: Alcian Blue; Cell Cycle; Mechanistic Target of Rapamycin Complex 1; Metaphase; Mitochondria; Mitochondrial Proteins; Phenazines; Phenothiazines; RNA, Messenger; Resorcinols
PubMed: 35559794
DOI: 10.7554/eLife.74552 -
American Journal of Respiratory and... Dec 2022The incidence and sites of mucus accumulation and molecular regulation of mucin gene expression in coronavirus (COVID-19) lung disease have not been reported. To...
The incidence and sites of mucus accumulation and molecular regulation of mucin gene expression in coronavirus (COVID-19) lung disease have not been reported. To characterize the incidence of mucus accumulation and the mechanisms mediating mucin hypersecretion in COVID-19 lung disease. Airway mucus and mucins were evaluated in COVID-19 autopsy lungs by Alcian blue and periodic acid-Schiff staining, immunohistochemical staining, RNA hybridization, and spatial transcriptional profiling. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected human bronchial epithelial (HBE) cultures were used to investigate mechanisms of SARS-CoV-2-induced mucin expression and synthesis and test candidate countermeasures. MUC5B and variably MUC5AC RNA concentrations were increased throughout all airway regions of COVID-19 autopsy lungs, notably in the subacute/chronic disease phase after SARS-CoV-2 clearance. In the distal lung, MUC5B-dominated mucus plugging was observed in 90% of subjects with COVID-19 in both morphologically identified bronchioles and microcysts, and MUC5B accumulated in damaged alveolar spaces. SARS-CoV-2-infected HBE cultures exhibited peak titers 3 days after inoculation, whereas induction of MUC5B/MUC5AC peaked 7-14 days after inoculation. SARS-CoV-2 infection of HBE cultures induced expression of epidermal growth factor receptor (EGFR) ligands and inflammatory cytokines (e.g., IL-1α/β) associated with mucin gene regulation. Inhibiting EGFR/IL-1R pathways or administration of dexamethasone reduced SARS-CoV-2-induced mucin expression. SARS-CoV-2 infection is associated with a high prevalence of distal airspace mucus accumulation and increased MUC5B expression in COVID-19 autopsy lungs. HBE culture studies identified roles for EGFR and IL-1R signaling in mucin gene regulation after SARS-CoV-2 infection. These data suggest that time-sensitive mucolytic agents, specific pathway inhibitors, or corticosteroid administration may be therapeutic for COVID-19 lung disease.
Topics: Humans; COVID-19; Prevalence; SARS-CoV-2; Mucin-5B; Mucin 5AC; Mucus; Lung; ErbB Receptors; RNA
PubMed: 35816430
DOI: 10.1164/rccm.202111-2606OC -
Frontiers in Immunology 2022Endometriosis is an estrogen dependent, chronic inflammatory disease characterized by the growth of endometrial lining outside of the uterus. Mast cells have emerged as...
Endometriosis is an estrogen dependent, chronic inflammatory disease characterized by the growth of endometrial lining outside of the uterus. Mast cells have emerged as key players in regulating not only allergic responses but also other mechanisms such as angiogenesis, fibrosis, and pain. The influence of estrogen on mast cell function has also been recognized as a potential factor driving disease pathophysiology in number of allergic and chronic inflammatory conditions. However, precise information is lacking on the cross talk between endocrine and immune factors within the endometriotic lesions and whether that contributes to the involvement of mast cells with disease pathophysiology. In this study, we observed a significant increase in mast cell numbers within endometriotic lesions compared to matched eutopic endometrium from the same patients. Compared to eutopic endometrium, endometriotic lesions had significantly higher levels of stem cell factor (SCF), a potent growth factor critical for mast cell expansion, differentiation, and survival for tissue resident mast cells. Targeted mRNA Q-PCR array revealed that the endometriotic lesions harbour microenvironment (upregulation of CPA3, VCAM1, CCL2, CMA1, CCR1, and KITLG) that is conducive to mast cells recruitment and subsequent differentiation. To examine cross-talk of mast cells within the endometriotic lesion microenvironment, endometriotic epithelial cells (12Z) and endometrial stromal cells (hESC) incubated with mast cell-conditioned media showed significantly increased production of pro-inflammatory and chemokinetic cytokines. To further understand the impact of estrogen on mast cells in endometriosis, we induced endometriosis in C57BL/6 mice. Mature mast cells were significantly higher in peritoneal fluid of estrogen-treated mice compared to untreated mice within the sham operated groups. Mouse endometriotic lesion tissue revealed several genes (qRT-PCR) relevant in mast cell biology significantly upregulated in the estrogen treated, endometriosis-induced group compared to control endometrium. The endometriotic lesions from estrogen treated mice also had significantly higher density of Alcian blue stained mast cells compared to untreated lesions or control endometrium. Collectively, these findings suggest that endometriotic lesions provide a microenvironment necessary for recruitment and differentiation of mast cells. In turn, mast cells potentially release pro-inflammatory mediators that contribute to chronic pelvic pain and endometriosis disease progression.
Topics: Animals; Cell Count; Endometriosis; Estrogens; Female; Humans; Mast Cells; Mice; Mice, Inbred C57BL
PubMed: 36016927
DOI: 10.3389/fimmu.2022.961599 -
Veterinary Journal (London, England :... Jul 2022The endothelial glycocalyx (eGlx) lines the luminal surface of endothelial cells. It is critical in maintaining vascular health and when damaged contributes to many...
The endothelial glycocalyx (eGlx) lines the luminal surface of endothelial cells. It is critical in maintaining vascular health and when damaged contributes to many diseases. Its fragility makes studying the eGlx technically challenging. The current reference standard for eGlx visualisation, by electron microscopy using glutaraldehyde/Alcian blue perfusion fixation, has not been previously reported in dogs. Established techniques were applied to achieve visualisation of the eGlx in the microvasculature of reproductive tissue in five healthy dogs undergoing elective neutering. Uterine and testicular artery samples underwent perfusion fixation, in the presence of Alcian blue, prior to transmission electron microscopy imaging. Image processing software was used to determine eGlx depth. EGlx was visualised in the arteries of two dogs, one testicular and one uterine, with median (range) eGlx depths of 68.2 nm (32.1-122.9 nm) and 47.6 nm (26.1-129.4 nm) respectively. Study of the eGlx is technically challenging, particularly its direct visualisation in clinical samples. Further research is needed to develop more clinically applicable techniques to measure eGlx health.
Topics: Alcian Blue; Animals; Dogs; Endothelial Cells; Glycocalyx; Perfusion
PubMed: 35640795
DOI: 10.1016/j.tvjl.2022.105844 -
Ocular Oncology and Pathology Sep 2021The goal of this study was to histopathologically evaluate the appearance of degrading MIRAgel scleral buckles so that they can be reliably distinguished by ophthalmic...
INTRODUCTION
The goal of this study was to histopathologically evaluate the appearance of degrading MIRAgel scleral buckles so that they can be reliably distinguished by ophthalmic pathologists from other foreign materials.
METHODS
Retrospective chart review and histopathologic study with special stains, including Alcian blue, periodic acid-Schiff, Masson's trichrome, and Perls' Prussian blue for iron, of 4 cases between 2017 and 2019.
RESULTS
Hydrolyzed MIRAgel scleral buckles from 4 patients had a consistent histopathologic appearance. They had a honeycomb structure with the walls of the lattice ranging from distinct to poorly defined. The walls of the lattice were positive for Alcian blue, while the contents of each cell contained periodic acid-Schiff-positive material. Other special stains were not as valuable in highlighting the material.
DISCUSSION
Although the capsules of MIRAgel scleral buckles have been well studied, the material itself has not been. While clinical history and radiographic appearance are often diagnostic of a hydrolyzed MIRAgel scleral buckle, there are instances of preoperative ambiguity where histopathologic confirmation can be useful.
CONCLUSIONS
MIRAgel scleral buckles have a distinct histopathologic appearance that can be readily distinguished from that of other foreign materials.
PubMed: 34604200
DOI: 10.1159/000514299