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Frontiers in Immunology 2022Climate change induced heat stress has increased coral bleaching events worldwide. Differentially regulated immune genes are one of the primary responses to heat stress...
Climate change induced heat stress has increased coral bleaching events worldwide. Differentially regulated immune genes are one of the primary responses to heat stress suggesting that immune activation is critical. However, the cellular immune mechanisms of coral bleaching is currently unknown, and it is still not known if the immune response documented during heat stress is a consequence of bleaching or is directly caused by the heat stress itself. To address this question, we have used two model system sea anemones (Order: Actiniaria): and . is an established sea anemone model for algal symbiont interaction, while is an established sea anemone model that lacks the algal symbiont. Here, we examined the effect of increased temperature on phagocytic activity, as an indication of immune function. Our data shows that immune cell activity increases during heat stress, while small molecule pinocytosis remains unaffected. We observed an increase in cellular production of reactive oxygen species with increasing temperatures. We also found that the cellular immune activity was not affected by the presence of the Symbiodiniaceae. Our results suggest that the immune activity observed in heat-stress induced bleaching in corals is a fundamental and basic response independent of the bleaching effect. These results establish a foundation for improving our understanding of hexacorallian immune cell biology, and its potential role in coral bleaching.
Topics: Animals; Anthozoa; Sea Anemones; Heat-Shock Response; Temperature; Reactive Oxygen Species
PubMed: 36618389
DOI: 10.3389/fimmu.2022.1016097 -
Pharmaceuticals (Basel, Switzerland) Dec 2022Plants have been considered for many years as an important source of medicine to treat different diseases. L. (Asteraceae, Compositae) is known for its diuretic,...
Plants have been considered for many years as an important source of medicine to treat different diseases. L. (Asteraceae, Compositae) is known for its diuretic, anti-inflammatory, and sedative effects. It is also used in the treatment of several ailments, such as cancer. In order to evaluate the anticancer and immunomodulatory activities, crude ethanol extract was prepared from the aerial part of and then fractionated using solvents with different polarities. As well, the chemical composition of extract and fractions were identified using LC-MS analysis. The antitumor effect of was assessed in both in vitro and in vivo models. Apoptosis induction was measured in vitro using a caspase-3 activity kit. Lymphocyte proliferation and phagocytosis and pinocytosis induction were used to quantify the effect of the plant extract and fractions on acquired and innate immunity, respectively. The effect of extract, and fractions on the levels of cytokines (IFN-γ, IL-2, IL-4, and IL-10) in murine lymphocytes was determined using a mouse-uncoated TH1/TH2 ELISA kit. Results showed that ethanol extract had the highest antiproliferative activity (IC₅₀ = 2.5 mg mL) against EMT6/P cell lines, while the aqueous and chloroform fractions had the highest apoptotic activity with 2.2 and 1.7 folds, respectively. On the other hand, the -hexane fraction was the most effective in stimulating lymphocyte proliferation, whereas ethanol extract, aq. Methanol and aqueous fractions exhibited the highest phagocytic activity. As well, extract and fractions were able to modulate the expression of IL-2, IL-4, and IFN-γ. A remarkable decrease in tumor size was accomplished following the treatment of tumor-bearing mice with extract and fractions. Both aq. Methanol and chloroform fractions showed the highest percentage change in tumor size with -58 and -55%, respectively. As well, tumor-bearing mice treated with chloroform fraction demonstrated a high curable percentage with a value of 57.1%. Anyway, extract and fractions exhibited no toxic impact on the liver or kidney functions of the mice-treated groups. These findings may confirm that has favorable anticancer and immunomodulatory effects. However, additional studies are required to fully understand the mechanisms of action of this plant and the signaling pathways involved in its effects. Moreover, more testing is needed to have better insight into the apoptotic pathway and to know the exact concentration of active compounds.
PubMed: 36558955
DOI: 10.3390/ph15121504 -
Frontiers in Immunology 2022Phagocytosis, macropinocytosis, and G protein coupled receptor-mediated chemotaxis are Ras-regulated and actin-driven processes. The common regulator for Ras activity in...
Phagocytosis, macropinocytosis, and G protein coupled receptor-mediated chemotaxis are Ras-regulated and actin-driven processes. The common regulator for Ras activity in these three processes remains unknown. Here, we show that C2GAP2, a Ras GTPase activating protein, highly expressed in the vegetative growth state in model organism . C2GAP2 localizes at the leading edge of chemotaxing cells, phagosomes during phagocytosis, and macropinosomes during micropinocytosis. cells lacking C2GAP2 displayed increased Ras activation upon folic acid stimulation and subsequent impaired chemotaxis in the folic acid gradient. In addition, cells have elevated phagocytosis and macropinocytosis, which subsequently results in faster cell growth. C2GAP2 binds multiple phospholipids on the plasma membrane and the membrane recruitment of C2GAP2 requires calcium. Taken together, we show a shared negative regulator of Ras signaling that mediates Ras signaling for chemotaxis, phagocytosis, and macropinocytosis.
Topics: Dictyostelium; Chemotaxis; Pinocytosis; Phagocytosis; Folic Acid
PubMed: 36524124
DOI: 10.3389/fimmu.2022.1075386 -
Journal of Virology Dec 2022Seneca Valley virus (SVV), a new pathogen resulting in porcine vesicular disease, is prevalent in pig herds worldwide. Although an understanding of SVV biology...
Seneca Valley virus (SVV), a new pathogen resulting in porcine vesicular disease, is prevalent in pig herds worldwide. Although an understanding of SVV biology pathogenesis is crucial for preventing and controlling this disease, the molecular mechanisms for the entry and post-internalization of SVV, which represent crucial steps in viral infection, are not well characterized. In this study, specific inhibitors, Western blotting, and immunofluorescence detection revealed that SVV entry into PK-15 cells depends on low-pH conditions and dynamin. Furthermore, results showed that caveolae-mediated endocytosis (CavME) contributes crucially to the internalization of SVV, as evidenced by cholesterol depletion, downregulation of caveolin-1 expression by small interfering RNA knockdown, and overexpression of a caveolin-1 dominant negative (caveolin-1-DN) in SVV-infected PK-15 cells. However, SVV entry into PK-15 cells did not depend on clathrin-mediated endocytosis (CME). Furthermore, treatment with specific inhibitors demonstrated that SVV entry into PK-15 cells via macropinocytosis depended on the Na+/H+ exchanger (NHE), p21-activated kinase 1 (Pak1), and actin rearrangement, but not phosphatidylinositol 3-kinase (PI3K). Electron microscopy showed that SVV particles or proteins were localized in CavME and macropinocytosis. Finally, knockdown of GTPase Rab5 and Rab7 by siRNA significantly inhibited SVV replication, as determined by measuring viral genome copy numbers, viral protein expression, and viral titers. In this study, our results demonstrated that SVV utilizes caveolae-mediated endocytosis and macropinocytosis to enter PK-15 cells, dependent on low pH, dynamin, Rab5, and Rab7. Entry of virus into cells represents the initiation of a successful infection. As an emerging pathogen of porcine vesicular disease, clarification of the process of SVV entry into cells enables us to better understand the viral life cycle and pathogenesis. In this study, patterns of SVV internalization and key factors required were explored. We demonstrated for the first time that SVV entry into PK-15 cells via caveolae-mediated endocytosis and macropinocytosis requires Rab5 and Rab7 and is independent of clathrin-mediated endocytosis, and that low-pH conditions and dynamin are involved in the process of SVV internalization. This information increases our understanding of the patterns in which all members of the family enter host cells, and provides new insights for preventing and controlling SVV infection.
Topics: Animals; Caveolae; Caveolin 1; Clathrin; Dynamins; Endocytosis; Picornaviridae; RNA, Small Interfering; Swine; Swine Vesicular Disease; Virus Internalization; rab5 GTP-Binding Proteins; Pinocytosis; Cell Line
PubMed: 36472440
DOI: 10.1128/jvi.01446-22 -
Science Signaling Nov 2022The lipid kinase VPS34 orchestrates autophagy, endocytosis, and metabolism and is implicated in cancer and metabolic disease. The proximal tubule in the kidney is a key...
The lipid kinase VPS34 orchestrates autophagy, endocytosis, and metabolism and is implicated in cancer and metabolic disease. The proximal tubule in the kidney is a key metabolic organ that controls reabsorption of nutrients such as fatty acids, amino acids, sugars, and proteins. Here, by combining metabolomics, proteomics, and phosphoproteomics analyses with functional and superresolution imaging assays of mice with an inducible deficiency in proximal tubular cells, we revealed that VPS34 controlled the metabolome of the proximal tubule. In addition to inhibiting pinocytosis and autophagy, VPS34 depletion induced membrane exocytosis and reduced the abundance of the retromer complex necessary for proper membrane recycling and lipid retention, leading to a loss of fuel and biomass. Integration of omics data into a kidney cell metabolomic model demonstrated that VPS34 deficiency increased β-oxidation, reduced gluconeogenesis, and enhanced the use of glutamine for energy consumption. Furthermore, the omics datasets revealed that VPS34 depletion triggered an antiviral response that included a decrease in the abundance of apically localized virus receptors such as ACE2. VPS34 inhibition abrogated SARS-CoV-2 infection in human kidney organoids and cultured proximal tubule cells in a glutamine-dependent manner. Thus, our results demonstrate that VPS34 adjusts endocytosis, nutrient transport, autophagy, and antiviral responses in proximal tubule cells in the kidney.
Topics: Humans; Animals; Mice; Glutamine; COVID-19; SARS-CoV-2; Kidney; Nutrients; Antiviral Agents; Lipids
PubMed: 36445937
DOI: 10.1126/scisignal.abo7940 -
The Journal of Cell Biology Jan 2023Macropinocytosis is a nonspecific endocytic process that may enhance cancer cell survival under nutrient-poor conditions. Ataxia-Telangiectasia mutated (ATM) is a tumor...
Macropinocytosis is a nonspecific endocytic process that may enhance cancer cell survival under nutrient-poor conditions. Ataxia-Telangiectasia mutated (ATM) is a tumor suppressor that has been previously shown to play a role in cellular metabolic reprogramming. We report that the suppression of ATM increases macropinocytosis to promote cancer cell survival in nutrient-poor conditions. Combined inhibition of ATM and macropinocytosis suppressed proliferation and induced cell death both in vitro and in vivo. Supplementation of ATM-inhibited cells with amino acids, branched-chain amino acids (BCAAs) in particular, abrogated macropinocytosis. Analysis of ATM-inhibited cells in vitro demonstrated increased BCAA uptake, and metabolomics of ascites and interstitial fluid from tumors indicated decreased BCAAs in the microenvironment of ATM-inhibited tumors. These data reveal a novel basis of ATM-mediated tumor suppression whereby loss of ATM stimulates protumorigenic uptake of nutrients in part via macropinocytosis to promote cancer cell survival and reveal a potential metabolic vulnerability of ATM-inhibited cells.
Topics: Humans; Adaptation, Physiological; Ataxia Telangiectasia Mutated Proteins; Cellular Reprogramming; Neoplasms; Pinocytosis; Tumor Microenvironment; Amino Acids, Branched-Chain; Metabolomics; Animals; Mice; Cell Line, Tumor
PubMed: 36399181
DOI: 10.1083/jcb.202007026 -
Frontiers in Cardiovascular Medicine 2022Atherosclerosis is a major cause of acute coronary syndrome and stroke. Foam cell formation in macrophages is involved in controlling plaque stability and the... (Review)
Review
Atherosclerosis is a major cause of acute coronary syndrome and stroke. Foam cell formation in macrophages is involved in controlling plaque stability and the pathogenesis of atherosclerosis. Accordingly, many studies have examined the processes of lipid incorporation, such as scavenger receptor-mediated uptake of oxidized low-density lipoprotein, in cells. In addition to receptor-mediated machinery, growing evidence has suggested that pinocytosis, which is a receptor-independent endocytic pathway, is associated with foam cell formation when a sufficient number of lipoproteins is accumulated around cells. Pinocytotic engulfment of nanoparticles is initiated by plasma membrane ruffling in a phosphatidylinositol-3 kinase-dependent manner. Subsequent to pinosome closure, the majority of pinosomes are internalized through endocytic processes, and they can be recycled into the plasma membrane. These pinocytotic processes are modulated by small GTPases and their cytoskeletal rearrangement. Moreover, pinocytotic abilities may vary between immunological subsets in cells. Accordingly, macrophages may show diverse pinocytotic abilities depending on the surrounding microenvironment. This review summarizes the current understanding of pinocytotic engulfment of lipoprotein in macrophages, and discusses how this endocytic process is governed under hypercholesterolemic conditions.
PubMed: 36105534
DOI: 10.3389/fcvm.2022.957897 -
Cells Aug 2022The skeletal muscle progenitors' proliferation and migration are crucial stages of myogenesis. Identifying drug candidates that contribute to myogenesis can have a...
The skeletal muscle progenitors' proliferation and migration are crucial stages of myogenesis. Identifying drug candidates that contribute to myogenesis can have a positive impact on atrophying muscle. The purpose of the study is to synthesize the (AC)-β-cyclodextrin (BCD) inclusion complex (IC) and understand its in vitro pro-regenerative influence in murine skeletal C2C12 myoblasts. The IC was subjected to various nano-characterization studies. Fluorescent IC was synthesized to understand the cellular uptake of IC. Furthermore, 25 µg/mL, 12.5 µg/mL, and 6.25 µg/mL of IC were tested on murine C2C12 skeletal muscle cells for their anti-inflammatory, pro-migratory, and pro-proliferative action. The cellular internalization of IC occurred rapidly via pinocytosis. IC (252.6 ± 3.2 nm size and -37.24 ± 1.55 surface charge) exhibited anti-inflammatory action by suppressing the secretion of interleukin-6 and enhanced cell proliferation with promising cytocompatibility. A 12.5 μg/mL dose of IC promoted cell migration in 24 h, but the same dose of AC significantly reduced cell migration, suggesting modification by BCD. Molecular studies revealed that IC promoted C2C12 myoblasts migration by upregulating long non-coding RNA (lncRNA) NEAT-1, SYISL, and activating the pPKC/β-catenin pathway. Our study is the first report on the pro-proliferative and pro-migratory effects of BCD-modified extracts of AC.
Topics: Animals; Anti-Inflammatory Agents; Antrodia; Mice; Muscle Development; Polyporales
PubMed: 36010589
DOI: 10.3390/cells11162512 -
Journal of Colloid and Interface Science Dec 2022Most experimental procedures applied in modern biology involve cargo delivering into cells. One of the ways to cargo introduction is osmotic-mediated intracellular...
HYPOTHESIS
Most experimental procedures applied in modern biology involve cargo delivering into cells. One of the ways to cargo introduction is osmotic-mediated intracellular vesicle swelling. However, its widespread use was hindered due to cargo size (<10 nm) and cell-type-related restrictions. We addressed the issue of the composition of colloidal loading solution to enhance the efficiency of cellular delivery.
EXPERIMENTS
We examined the effectiveness of colloidal loading solutions of varied compositions, including various types and sizes of polymers building osmotic pressure. We used confocal imaging coupled with fluorescence correlation spectroscopy to evaluate the introduction of polymers, proteins, nanoparticles, and DNA plasmids (cargos of sizes 1-175 nm) to cells representing eight cell lines: cancer, normal, epithelial, and mesenchymal ones.
FINDINGS
We found that cellular delivery effectiveness strongly correlates with the size and concentration of osmotic pressure building polymers and not with the high value of the osmotic pressure itself. We show that polymer solutions at the entangled regime of concentrations enhance the delivery of large biomacromolecules even of size 200 nm (DNA plasmids) into cells, including MDA-MB-231 cells - so far resistant to the osmotic procedure. We show that the colloid loading medium based on entangled polymer chains is a versatile cargo delivery tool for molecular biology.
Topics: Colloids; DNA; Nanoparticles; Plasmids; Polymers
PubMed: 35849860
DOI: 10.1016/j.jcis.2022.07.040 -
Frontiers in Nutrition 2022From the earliest times, manna has been widely used as a tasty local sweet or folk medicine. The type of manna being investigated in the present study is called...
BACKGROUND
From the earliest times, manna has been widely used as a tasty local sweet or folk medicine. The type of manna being investigated in the present study is called Gaz-alafi, a mixture of insect and leaves secretions from oak forests in the north of Iraq and west of Iran.
METHODS
Aqueous and ethanol extracts were prepared as decoction. Various phytochemical tests were conducted to analyze manna composition, including total phenolic contents using the Folin-Ciocalteu method and LC-MS. Gallic acid and catechin were detected in both extracts, in addition to tiliroside presence in ethanol extract, which added more value to the phenolic content of ethanol extract. Cytotoxic activities of Gaz alafi were evaluated against breast cancer cell lines and compared to normal cell lines and doxorubicin using the MTT assay. Antimicrobial properties were assessed against , and using the dilution method of the micro-titer plate. Serum levels of IFN-γ, interleukin-2 (IL-2), interleukin-4 (IL-4), and interleukin-10 (IL-10) were measured using ELISA. The effect of extracts on splenocyte proliferation was evaluated using the lymphocytes proliferation assay. Macrophage function was evaluated using the nitro blue tetrazolium assay, whereas pinocytosis was evaluated using the neutral red uptake assay. Ten days after tumor inoculation, changes in tumor size, survival rates, levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and creatinine were measured.
RESULTS
The growth of cancer cells was inhibited by Gaz alafi ethanol extract. An alteration in IFN- γ, IL-2, and IL-4 levels toward antiproliferation immune response were reported for both extracts. The aqueous extract efficiently stimulated lymphocyte proliferation, phagocytosis, and pinocytosis, followed by the ethanol extracts with moderate activity. After treating the mice with ethanol extracts, a significant reduction in tumor size and several undetected tumors were recorded.
CONCLUSIONS
Gaz alafi extracts (aqueous and ethanol) are promising sources for anticancer and immunostimulatory agents. Further studies are needed to fully identify the chemical composition of Gaz alafi extracts.
PubMed: 35845806
DOI: 10.3389/fnut.2022.900506