Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is an RNA virus responsible for coronavirus disease 2019 (COVID-19). While SARS-CoV-2 primarily targets the lungs and airways, it can also infect other organs, including the central nervous system (CNS). The aim of this study was to investigate whether the choroid plexus could serve as a potential entry site for SARS-CoV-2 into the brain. Tissue samples from 24 deceased COVID-19-positive individuals were analyzed. Reverse transcription real-time PCR (RT-qPCR) was performed on selected brain regions, including the choroid plexus, to detect SARS-CoV-2 viral RNA. Additionally, immunofluorescence staining and confocal microscopy were used to detect and localize two characteristic proteins of SARS-CoV-2: the spike protein S1 and the nucleocapsid protein. RT-qPCR analysis confirmed the presence of SARS-CoV-2 viral RNA in the choroid plexus. Immunohistochemical staining revealed viral particles localized in the epithelial cells of the choroid plexus, with the spike protein S1 detected in the late endosomes. Our findings suggest that the blood-cerebrospinal fluid (B-CSF) barrier in the choroid plexus serves as a route of entry for SARS-CoV-2 into the CNS. This study contributes to the understanding of the mechanisms underlying CNS involvement in COVID-19 and highlights the importance of further research to explore potential therapeutic strategies targeting this entry pathway.
- MeSH
- COVID-19 * virology MeSH
- Adult MeSH
- Phosphoproteins * metabolism MeSH
- Spike Glycoprotein, Coronavirus * genetics metabolism MeSH
- Blood-Brain Barrier * virology MeSH
- Virus Internalization MeSH
- Coronavirus Nucleocapsid Proteins MeSH
- Middle Aged MeSH
- Humans MeSH
- Choroid Plexus * virology MeSH
- RNA, Viral * genetics MeSH
- SARS-CoV-2 * physiology MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
Berberine (BBR), a small molecule protoberberine isoquinoline alkaloid, is easy to cross the blood-brain barrier and is a potential drug for neurodegenerative diseases. Here, we explored the role and molecular mechanism of BBR in Alzheimer's disease (AD) progression. Weighted gene co-expression network analysis (WGCNA) was conducted to determine AD pathology-associated gene modules and differentially expressed genes (DEGs) were also identified. GO and KEGG analyses were performed for gene function and signaling pathway annotation. Cell counting kit-8 (CCK8) assay was applied to analyze cell viability. Immunofluorescence (IF) staining assay was conducted to measure the levels of polarization markers. The production of inflammatory cytokines was analyzed by enzyme-linked immunosorbent assay (ELISA). Reactive oxygen species (ROS) level and mitochondrial membrane potential (MMP) were detected using a ROS detection kit and a MMP Detection Kit (JC-1), respectively. AD pathology-associated DEGs were applied for GO function annotation and KEGG enrichment analysis, and the results uncovered that AD pathology was related to immune and inflammation. Lipopolysaccharide (LPS) exposure induced the M1 phenotype of microglia, and BBR suppressed LPS-induced M1 polarization and induced microglia toward M2 polarization. Through co-culture of microglia and neuronal cells, we found that BBR exerted a neuro-protective role by attenuating the injury of LPS-induced HMC3 on SH-SY5Y cells. Mechanically, BBR switched the M1/M2 phenotypes of microglia by activating PI3K-AKT signaling. In summary, BBR protected neuronal cells from activated microglia-mediated neuro-inflammation by switching the M1/M2 polarization in LPS-induced microglia via activating PI3K-AKT signaling. Key words Alzheimer's Disease, Berberine, Microglia polarization, Neuroinflammation, PI3K-AKT signaling.
- MeSH
- Alzheimer Disease * metabolism drug therapy pathology MeSH
- Berberine * pharmacology therapeutic use MeSH
- Phosphatidylinositol 3-Kinases * metabolism MeSH
- Humans MeSH
- Microglia * drug effects metabolism MeSH
- Mice MeSH
- Neuroprotective Agents * pharmacology MeSH
- Cell Polarity drug effects MeSH
- Proto-Oncogene Proteins c-akt * metabolism MeSH
- Signal Transduction * drug effects MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
BACKGROUND: The neuropeptide B/W signalling system (NPB/W) has been identified in multiple body regions and is integral to several physiological processes, including the regulation of food intake and energy homeostasis. Recently, it has also been detected in human skin; however, its specific functions in this context remain to be thoroughly investigated. This study aims to identify the expression of neuropeptides B/W receptor 1 (NPBWR1) and neuropeptides B/W receptor 2 (NPBWR2) in human dermal fibroblasts of mesenchymal origin using genomic and proteomic techniques. We will also investigate the role of these receptors in cell proliferation and calcium signalling. METHODS: The mRNAs for NPBWR1 and NPBWR2 were detected using quantitative PCR (qPCR) analysis and further validated by western blot and immunofluorescence analyses. Additionally, we synthesised ligands for these receptors, specifically hNPB (25-53) and hNPW (33-62), to investigate their effects on cell proliferation and intracellular calcium levels in human fibroblasts. RESULTS: Our results demonstrated that hNPW (33-62) has anti-proliferative effect on human dermal fibroblasts and concentration of 0.1-μmol/L can significantly decrease intracellular calcium levels (p < 0.05). CONCLUSION: This finding suggests a potential role for the NPB/W signalling system in pathologies associated with impaired calcium handling, such as fibrosis. Furthermore, we observed that the proliferation of human fibroblasts was not affected by hNPB (25-53). Our findings could lead to the development of new therapeutic strategies for various skin conditions and improved wound healing.
- MeSH
- Fibroblasts * metabolism MeSH
- Cells, Cultured MeSH
- Skin * metabolism cytology MeSH
- Humans MeSH
- Neuropeptides metabolism genetics MeSH
- Cell Proliferation * MeSH
- Receptors, Neuropeptide metabolism genetics MeSH
- Signal Transduction MeSH
- Calcium * metabolism MeSH
- Calcium Signaling MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Background: A hallmark of cancer is the presence of an immunosuppressive tumor microenvironment (TME). Immunosuppressive M2 macrophages (MΦs) in the TME facilitate escape from immune surveillance and promote tumor growth; therefore, TME-induced immunosuppression is a potent immunotherapeutic approach to treating cancer. Methods: Cancer cell-secreted proteins were detected by using liquid chromatography-mass spectrometry (LC-MS). Neutralizing antibodies (nAbs) were used to assess which proteins were involved in MΦs polarization and differentiation. The protein-protein interaction was characterized using co-immunoprecipitation and immunofluorescence assays. Cancer-secreted heat shock protein 70 (Hsp70) protein was quantified using an enzyme-linked immunosorbent assay (ELISA). MΦ polarization and tumor growth were assessed in vivo with subcutaneous LLC-GFP tumor models and toll-like receptor 2 (TLR2) knockout mice; in vitro assessments were conducted using TLR2 knockout and both LLC-GFP and LN227 lentiviral-mediated knockdown (KD) cells. Results: Cancer cells released a secreted form of Hsp70 that acted on MΦ TLR2 to upregulate Mer receptor tyrosine kinase (MerTK) and induce MΦ M2 polarization. Hsp70 nAbs led to a reduction in CD14 expression by 75% in THP-1 cells in response to Gli36 EMD-CM. In addition, neutralizing TLR2 nAbs resulted in a 30% and 50% reduction in CD14 expression on THP-1 cells in response to MiaPaCa-2 and Gli36 exosome/microparticle-depleted conditioned media (EMD-CMs), respectively. Hsp70, TLR2, and MerTK formed a protein complex. Tumor growth and intra-tumor M2 MΦs were significantly reduced upon cancer cell Hsp70 knockdown and in TLR2 knockout mice. Conclusions: Cancer-secreted Hsp70 interacts with TLR2, upregulates MerTK on MΦs, and induces immunosuppressive MΦ M2 polarization. This previously unreported action of secreted Hsp70 suggests that disrupting the Hsp70-TLR2-MerTK interaction could serve as a promising immunotherapeutic approach to mitigate TME immunosuppression in solid cancers.
- Publication type
- Journal Article MeSH
The evaluation of large experimental datasets is a fundamental aspect of research in every scientific field. Streamlining this process can improve the reliability of results while making data analysis more efficient and faster to execute. In biomedical research it is often very important to determine the type of cell death after various treatments. Thus, differentiating between viable, apoptotic, and necrotic cells provide critical insights into the treatment efficacy, a key aspect in the field of drug development. Fluorescent microscopy is perceived as a widely used technique for cell metabolism assessment and can therefore be used to investigate treatment outcomes after staining samples with cell death detection kit. However, accurate evaluation of therapeutic results requires quantitative analysis, often necessitating extensive postprocessing of imaging data. In this study, we introduce a complementary tool designed as a macro for the Fiji platform, enabling the automated postprocessing of fluorescent microscopy images to accurately distinguish and quantify viable, apoptotic, and necrotic cells.
- MeSH
- Apoptosis MeSH
- Cell Death MeSH
- Microscopy, Fluorescence * methods MeSH
- Humans MeSH
- Necrosis MeSH
- Image Processing, Computer-Assisted * methods MeSH
- Software MeSH
- Cell Survival MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
INTRODUCTION: The choroid plexus is located in the cerebral ventricles. It consists of a stromal core and a single layer of cuboidal epithelial cells that forms the blood-cerebrospinal barrier. The main function of the choroid plexus is to produce cerebrospinal fluid. Subarachnoid hemorrhage due to aneurysm rupture is a devastating type of hemorrhagic stroke. Following subarachnoid hemorrhage, blood and the blood degradation products that disperse into the cerebrospinal fluid come in direct contact with choroid plexus epithelial cells. The aim of the current study was to elucidate the pathophysiological cascades responsible for the inflammatory reaction that is seen in the choroid plexus following subarachnoid hemorrhage. METHODS: Subarachnoid hemorrhage was induced in rats by injecting non-heparinized autologous blood to the cisterna magna. Increased intracranial pressure following subarachnoid hemorrhage was modeled by using artificial cerebrospinal fluid instead of blood. Subarachnoid hemorrhage and artificial cerebrospinal fluid animals were left to survive for 1, 3, 7 and 14 days. Immunohistochemical staining of TLR4, TLR9, FPR2, CCL2, TNFα, IL-1β, CCR2 and CX3CR1 was performed on the cryostat sections of choroid plexus tissue. The level of TLR4, TLR9, FPR2, CCL2, TNFα, IL-1β was detected by measuring immunofluorescence intensity in randomly selected epithelial cells. The number of CCR2 and CX3CR1 positive cells per choroid plexus area was manually counted. Immunohistochemical changes were confirmed by Western blot analyses. RESULTS: Immunohistochemical methods and Western blot showed increased levels of TLR9 and a slight increase in TLR4 and FRP2 following both subarachnoid hemorrhage as well as the application of artificial cerebrospinal fluid over time, although the individual periods were different. The levels of TNFα and IL-1β increased, while CCL2 level decreased slightly. Accumulation of macrophages positive for CCR2 and CX3CR1 was found in all periods after subarachnoid hemorrhage as well as after the application of artificial cerebrospinal fluid. DISCUSSION: Our results suggest that the inflammation develops in the choroid plexus and blood-cerebrospinal fluid barrier in response to blood components as well as acutely increased intracranial pressure following subarachnoid hemorrhage. These pro-inflammatory changes include accumulation in the choroid plexus of pro-inflammatory cytokines, innate immune receptors, and monocyte-derived macrophages.
- Publication type
- Journal Article MeSH
This study aimed to establish a rat model of chronic wounds to observe the effects of hyperbaric oxygen (HBO) on chronic wound repair and pyroptosis and explore the potential role of pyroptosis in the pathogenesis of chronic wounds. Sprague-Dawley (SD) rats were randomly divided into acute wound group (control group), chronic wound group (model group), chronic wound + HBO treatment group (HBO group), and chronic wound + VX-765 (IL-converting enzyme/Caspase-1 inhibitor) treatment group (VX-765 group). After 7 days of respective interventions, the wound healing status was observed, and wound tissue specimens were collected. Hematoxylin and eosin (HE) staining was used to observe the pathological changes in wound tissues. Transmission electron microscopy was used to observe the changes in cellular ultrastructure. Immunofluorescence was used to observe the expression and localization of vascular endothelial growth factor A (VEGF-A) and the N-terminal domain of gasdermin D (GSDMD-N). Western blot was conducted to detect the expression of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), cysteine-requiring aspartate protease-1 (Caspase-1), VEGF-A, and GSDMD-N proteins in wound tissues. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to detect the expression of NLRP3, Caspase-1, and GSDMD genes. Enzyme-linked immunosorbent assay (ELISA) was performed to observe the expression of the inflammatory cytokines interleukin-1 beta (IL-1beta) and IL-18. The results showed that the HBO group had a faster wound healing rate and better pathology improvement compared to the model group. The expression level of VEGF-A was higher in the HBO group compared to the model group, while the expression levels of NLRP3, Caspase-1, GSDMD, IL-1beta, and IL-18 were lower than those in the model group. HBO can effectively promote the healing of chronic wounds, and the regulation of pyroptosis may be one of its mechanisms of action. Keywords: Hyperbaric oxygen, Pyroptosis, Chronic wounds, Inflammatory.
- MeSH
- Chronic Disease MeSH
- Gasdermins MeSH
- Wound Healing * physiology MeSH
- Hyperbaric Oxygenation * methods MeSH
- Rats MeSH
- Rats, Sprague-Dawley * MeSH
- NLR Family, Pyrin Domain-Containing 3 Protein metabolism MeSH
- Phosphate-Binding Proteins metabolism MeSH
- Pyroptosis * physiology MeSH
- Vascular Endothelial Growth Factor A metabolism genetics MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Male MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
A subpopulation of astrocytes on the brain's surface, known as subpial astrocytes, constitutes the "glia limitans superficialis" (GLS), which is an interface between the brain parenchyma and the cerebrospinal fluid (CSF) in the subpial space. Changes in connexin-43 (Cx43) and aquaporin-4 (AQP4) proteins in subpial astrocytes were examined in the medial prefrontal cortex at postoperative day 1, 3, 7, 14, and 21 after sham operation and sciatic nerve compression (SNC). In addition, we tested the altered uptake of TRITC-conjugated 3 kDa dextran by reactive subpial astrocytes. Cellular immunofluorescence (IF) detection and image analysis were used to examine changes in Cx43 and AQP4 protein levels, as well as TRITC-conjugated 3 kDa dextran, in subpial astrocytes. The intensity of Cx43-IF was significantly increased, but AQP4-IF decreased in subpial astrocytes of sham- and SNC-operated rats during all survival periods compared to naïve controls. Similarly, the uptake of 3 kDa dextran in the GLS was reduced following both sham and SNC operations. The results suggest that both sciatic nerve injury and peripheral tissue injury alone can induce changes in subpial astrocytes related to the spread of their reactivity across the cortical surface mediated by increased amounts of gap junctions. At the same time, water transport and solute uptake were impaired in subpial astrocytes.
- MeSH
- Aquaporin 4 * metabolism MeSH
- Astrocytes * metabolism MeSH
- Dextrans * metabolism MeSH
- Connexin 43 * metabolism MeSH
- Rats MeSH
- Sciatic Nerve * injuries metabolism MeSH
- Rats, Sprague-Dawley MeSH
- Prefrontal Cortex * metabolism MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Male MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
Xi-Kun Yuan Pin-Shi Ni Zhen-Hao Yan Zhi Yu Zhuang-Zhi Wang Chen-Kai Zhang Fang-Hui Li Xiao-Ming Yu 1Sports Department, Nanjing University of Science and Technology ZiJin College, Nanjing, China, 2School of Sport Sciences, Nanjing Normal University, Nanjing, China, 3Shanghai Seventh People's Hospital, Shanghai, China To investigate the effects of life-long exercise (LLE) on age-related inflammatory cytokines, apoptosis, oxidative stress, ferroptosis markers, and the NRF2/KAEP 1/Klotho pathway in rats. Eight-month-old female Sprague-Dawley rats were divided into four groups: 1) LLE: 18-month LLE training starting at 8 months of age, 2) Old moderate-intensity continuous training (OMICT): 8 months of moderate-intensity continuous training starting at 18 months of age, 3) Adult sedentary (ASED): 8 month-old adult sedentary control group, and 4) Old sedentary (OSED): a 26-month-old sedentary control group. Hematoxylin eosin staining was performed to observe the pathological changes of kidney tissue injury in rats; Masson's staining to observe the deposition of collagen fibers in rat kidney tissues; and western blotting to detect the expression levels of IL-6, IL 1beta, p53, p21, TNF-alpha, GPX4, KAEP 1, NRF2, SLC7A11, and other proteins in kidney tissues. Results: Compared with the ASED group, the OSED group showed significant morphological changes in renal tubules and glomeruli, which were swollen and deformed, with a small number of inflammatory cells infiltrated in the tubules. Compared with the OSED group, the expression levels of inflammation-related proteins such as IL-1beta, IL-6, TNF alpha, and MMP3 were significantly lower in the LLE group. Quantitative immunofluorescence analysis and western blotting revealed that compared with the ASED group, KAEP 1 protein fluorescence intensity and protein expression levels were significantly enhanced, while Klotho and NRF2 protein fluorescence intensity and protein expression levels were reduced in the OSED group. Compared with the OSED group, KAEP 1 protein fluorescence intensity and protein expression levels were reduced in the LLE and OMICT groups. Klotho and KAEP 1 protein expression levels and immunofluorescence intensity were higher in the LLE group than in the OSED group. The expression levels of GPX4 and SLC7A11, two negative marker proteins associated with ferroptosis, were significantly higher in the LLE group than in the OSED group, while the expression of p53 a cellular senescence-associated protein that negatively regulates SLC7A11, and the downstream protein p21 were significantly decreased. LLE may ameliorated aging-induced oxidative stress, inflammatory response, apoptosis, and ferroptosis by regulating Klotho and synergistically activating the NRF2/KAEP 1 pathway. Keywords: Life-long exercise, Moderate intensity continuous training, Aging, Kidney tissue, Ferroptosis.
- MeSH
- Apoptosis * physiology MeSH
- Biomarkers metabolism MeSH
- NF-E2-Related Factor 2 * metabolism MeSH
- Ferroptosis * physiology MeSH
- Glucuronidase metabolism MeSH
- Physical Conditioning, Animal * physiology MeSH
- Rats MeSH
- Kidney * metabolism pathology MeSH
- Oxidative Stress * physiology MeSH
- Rats, Sprague-Dawley * MeSH
- Klotho Proteins * MeSH
- Signal Transduction physiology MeSH
- Aging metabolism pathology MeSH
- Inflammation metabolism pathology MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
Tick-borne encephalitis virus (TBEV) targets the central nervous system (CNS), leading to potentially severe neurological complications. The neurovascular unit plays a fundamental role in the CNS and in the neuroinvasion of TBEV. However, the role of human brain pericytes, a key component of the neurovascular unit, during TBEV infection has not yet been elucidated. In this study, TBEV infection of the primary human brain perivascular pericytes was investigated with highly virulent Hypr strain and mildly virulent Neudoerfl strain. We used Luminex assay to measure cytokines/chemokines and growth factors. Both viral strains showed comparable replication kinetics, peaking at 3 days post infection (dpi). Intracellular viral RNA copies peaked at 6 dpi for Hypr and 3 dpi for Neudoerfl cultures. According to immunofluorescence staining, only small proportion of pericytes were infected (3% for Hypr and 2% for Neudoerfl), and no cytopathic effect was observed in the infected cells. In cell culture supernatants, IL-6 production was detected at 3 dpi, together with slight increases in IL-15 and IL-4, but IP-10, RANTES and MCP-1 were the main chemokines released after TBEV infection. These chemokines play key roles in both immune defense and immunopathology during TBE. This study suggests that pericytes are an important source of these signaling molecules during TBEV infection in the brain.
- MeSH
- Chemokine CCL5 * metabolism MeSH
- Chemokine CXCL10 * metabolism MeSH
- Cytokines metabolism MeSH
- Encephalitis, Tick-Borne * virology metabolism MeSH
- Cells, Cultured MeSH
- Humans MeSH
- Brain * virology metabolism pathology MeSH
- Pericytes * virology metabolism MeSH
- Virus Replication MeSH
- Encephalitis Viruses, Tick-Borne * physiology pathogenicity MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH