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1.
PLoS One ; 19(4): e0300331, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635511

RESUMO

The performance of apparently biocompatible implanted bovine bone grafts may be compromised by unresolved chronic inflammation, and poor graft incorporation leading to implant failure. Monitoring the intensity and duration of the inflammatory response caused by implanted bone grafts is crucial. In this study, the ability of demineralized (DMB) and decellularized (DCC) bovine bone substitutes in initiating inflammatory responses to peripheral blood monocyte-derived macrophages (PBMMs) was investigated. The response of PBMMs to bone substitutes was evaluated by using both direct and indirect cell culture, reactive oxygen species (ROS) generation, apoptosis, immunophenotyping, and cytokine production. Analysis of DMB and DCC substitutes using scanning electron microscope (SEM) showed a roughened surface with a size ranging between 500 and 750 µm. PBMMs treated with DMB demonstrated cell aggregation and clumping mimicking lipopolysaccharide (LPS) treated PBMMs and a higher proliferation ability (166.93%) compared to control (100%) and DCC treatments (115.64%; p<0.001) at 24h. This was associated with a significantly increased production of intracellular ROS in PBMMs exposed to DMB substitutes than control (3158.5 vs 1715.5; p<0.001) and DCC treatment (2117.5). The bone substitute exposure also caused an increase in percentage apoptosis which was significantly (p<0.0001) higher in both DMB (27.85) and DCC (29.2) treatment than control (19.383). A significant increase in proinflammatory cytokine expression (TNF-α: 3.4 folds; p<0.05) was observed in DMB substitute-treated PBMMs compared to control. Notably, IL-1ß mRNA was significantly higher in DMB (21.75 folds; p<0.0001) than control and DCC (5.01 folds). In contrast, DCC substitutes exhibited immunoregulatory effects on PBMMs, as indicated by the expression for CD86, CD206, and HLDR surface markers mimicking IL-4 treatments. In conclusion, DMB excites a higher immunological response compared to DCC suggesting decellularization process of tissues dampen down inflammatory reactions when exposed to PBMM.


Assuntos
Substitutos Ósseos , Humanos , Animais , Bovinos , Espécies Reativas de Oxigênio/metabolismo , Macrófagos/metabolismo , Citocinas/metabolismo , Inflamação/metabolismo , Interleucina-1beta/metabolismo
2.
Sci Rep ; 13(1): 10722, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37400519

RESUMO

Recently, 1-nonadecene and L-lactic acid were identified as unique metabolites in radicular cysts and periapical granuloma, respectively. However, the biological roles of these metabolites were unknown. Therefore, we aimed to investigate the inflammatory and mesenchymal-epithelial transition (MET) effects of 1-nonadecene, and the inflammatory and collagen precipitation effects of L-lactic acid on both periodontal ligament fibroblasts (PdLFs) and peripheral blood mononuclear cells (PBMCs). PdLFs and PBMCs were treated with 1-nonadecene and L-lactic acid. Cytokines' expression was measured using quantitative real-time polymerase chain reaction (qRT-PCR). E-cadherin, N-cadherin, and macrophage polarization markers were measured using flow cytometry. The collagen, matrix metalloproteinase (MMP)-1, and released cytokines were measured using collagen assay, western blot, and Luminex assay, respectively. In PdLFs, 1-nonadecene enhances inflammation through the upregulation of some inflammatory cytokines including IL-1ß, IL-6, IL-12A, monocyte chemoattractant protein (MCP)-1, and platelet-derived growth factor (PDGF) α. 1-Nonadecene also induced MET through the upregulation of E-cadherin and the downregulation of N-cadherin in PdLFs. 1-Nonadecene polarized macrophages to a pro-inflammatory phenotype and suppressed their cytokines' release. L-lactic acid exerted a differential impact on the inflammation and proliferation markers. Intriguingly, L-lactic acid induced fibrosis-like effects by enhancing collagen synthesis, while inhibiting MMP-1 release in PdLFs. These results provide a deeper understanding of 1-nonadecene and L-lactic acid's roles in modulating the microenvironment of the periapical area. Consequently, further clinical investigation can be employed for target therapy.


Assuntos
Granuloma Periapical , Cisto Radicular , Humanos , Granuloma Periapical/metabolismo , Leucócitos Mononucleares/metabolismo , Virulência , Citocinas , Inflamação , Ácido Láctico , Microambiente Tumoral
3.
Curr Issues Mol Biol ; 45(4): 3462-3478, 2023 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-37185751

RESUMO

The blood-brain barrier (BBB) is part of a neurovascular structure located in the brain's micro vessels, that is essential to maintain brain homeostasis, but prevents the brain uptake of most drugs. Because of its importance in neuro-pharmacotherapy, the BBB has been the subject of extensive research since its discovery over 100 years ago. Major advances in understanding the structure and function of the barrier have been made. Drugs are re-designed to cross the BBB. However, despite these efforts, overcoming the BBB efficiently to treat brain diseases safely remains challenging. The majority of BBB research studies focus on the BBB as a homogenous structure throughout the different brain regions. However, this simplification may lead to an inadequate understanding of the BBB function with significant therapeutic consequences. From this perspective, we analyzed the gene and protein expression profiles of the BBB in the micro vessels from the brains of mice that were isolated from two different brain regions, namely the cortex and the hippocampus. The expression profile of the inter-endothelial junctional protein (claudin-5), three ABC transporters (P-glycoprotein, Bcrp and Mrp-1), and three BBB receptors (lrp-1, TRF and GLUT-1) were analyzed. Our gene and protein analysis showed that the brain endothelium in the hippocampus exhibits different expression profiles compared to the brain cortex. Specifically, brain endothelial cells (BECs) of the hippocampus express higher gene levels of abcb1, abcg2, lrp1, and slc2a1 compared to the BECs of the cortex regions with a trend of increase for claudin-5, while BECs of the cortex express higher gene levels of abcc1 and trf compared to the hippocampus. At the protein levels, the P-gp expression was found to be significantly higher in the hippocampus compared to the cortex, while TRF was found to be up-regulated in the cortex. These data suggest that the structure and function of the BBB are not homogeneous, and imply that drugs are not delivered similarly among the different brain regions. Appreciation of the BBB heterogeneity by future research programs is thus critical for efficient drug delivery and the treatment of brain diseases.

4.
Exp Biol Med (Maywood) ; 248(4): 339-349, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36740767

RESUMO

Mounting evidence points to a link between growth differentiation factor-15 (GDF15) expression and the onset and progression of diabetes mellitus. However, the exact role of GDF15 in pancreatic ß-cell function is unclear. To examine the role of GDF15 in ß-cell function, bioinformatics analysis and functional experiments involving GDF15 silencing and overexpression were performed in INS-1 cells and human islets. Public microarray and RNA-seq expression data showed that islets obtained from diabetic donors express high levels of GDF15 compared to islets obtained from normal donors. Moreover, analysis of RNA-seq expression data revealed that GDF15 expression correlates positively with that of insulin (INS), KCNJ11, GLUT1, MAFA, INSR and negatively with that of Glucokinase (GCK) and Alpha-Ketoglutarate Dependent Dioxygenase (FTO). No T2D-associated genetic variants in the GDF15 were found to pass genome-wide significance in the TIGER portal. Expression silencing of Gdf15 in INS-1 cells reduced insulin release, glucose uptake levels, increased reactive oxygen species (ROS) production and apoptosis levels. While Gdf15-silenced cells downregulated mRNA expression of Ins, Pdx1, Mafa, and Glut2 genes, its overexpression human islets was associated with increased insulin secretion and upregulated expression of MAFA and GLUT1 but not INS or GCK. Silencing of Pdx1 or Mafa in INS-1 cells did not affect the expression of GDF15. These findings suggest that GDF15 plays a significant role in pancreatic ß-cell function.


Assuntos
Células Secretoras de Insulina , Ilhotas Pancreáticas , Humanos , Secreção de Insulina , Transportador de Glucose Tipo 1/metabolismo , Ilhotas Pancreáticas/metabolismo , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Glucose/metabolismo , Fator 15 de Diferenciação de Crescimento/genética , Fator 15 de Diferenciação de Crescimento/metabolismo , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo
5.
PLoS One ; 18(1): e0280592, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36656874

RESUMO

The large-scale dissemination of coronavirus disease-2019 (COVID-19) and its serious complications have pledged the scientific research communities to uncover the pathogenesis mechanisms of its etiologic agent, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Methods of unveiling such mechanisms are rooted in understanding the viral agent's interactions with the immune system, including its ability to activate macrophages, due to their suggested role in prolonged inflammatory phases and adverse immune responses. The objective of this study is to test the effect of SARS-CoV-2-free proteins on the metabolic and immune responses of macrophages. We hypothesized that SARS-CoV-2 proteins shed during the infection cycle may dynamically induce metabolic and immunologic alterations with an inflammatory impact on the infected host cells. It is imperative to delineate such alterations in the context of macrophages to gain insight into the pathogenesis of these highly infectious viruses and their associated complications and thus, expedite the vaccine and drug therapy advent in combat of viral infections. Human monocyte-derived macrophages were treated with SARS-CoV-2-free proteins at different concentrations. The phenotypic and metabolic alterations in macrophages were investigated and the subsequent metabolic pathways were analyzed. The obtained results indicated that SARS-CoV-2-free proteins induced concentration-dependent alterations in the metabolic and phenotypic profiles of macrophages. Several metabolic pathways were enriched following treatment, including vitamin K, propanoate, and the Warburg effect. These results indicate significant adverse effects driven by residual viral proteins that may hence be considered determinants of viral pathogenesis. These findings provide important insight as to the impact of SARS-CoV-2-free residual proteins on the host cells and suggest a potential new method of management during the infection and prior to vaccination.


Assuntos
COVID-19 , Macrófagos , SARS-CoV-2 , Humanos , COVID-19/metabolismo , Macrófagos/metabolismo , Macrófagos/virologia , Proteínas Virais/metabolismo
6.
J Endod ; 49(2): 169-177.e3, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36528175

RESUMO

INTRODUCTION: Periapical abscesses are 1 of the most frequent pathologic lesions in the alveolar bone. Recently, we have identified 17-octadecynoic acid (17-ODYA) as the highest unique metabolite in periapical abscesses. Therefore, the aim of this study was to investigate the immunologic and pathophysiological roles of this metabolite in the initiation and development of periapical abscesses. METHODS: Periodontal ligament fibroblasts and peripheral blood mononuclear cells were treated with 17-ODYA. Gene expression analysis and interleukin (IL)-8 release were determined using quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay. Macrophage polarization and cytokine release were also determined using flow cytometry and Luminex bioassay (R&D Systems, Minneapolis, MN), respectively. RESULTS: In periodontal ligament fibroblasts, 17-ODYA caused significant (P < .0001) up-regulation of IL-1α, IL-1ß, IL-6, matrix metalloproteinase-1, and monocyte chemoattractant protein-1 at 10 µmol/L after 6 days of treatment and up-regulation of platelet-derived growth factor alpha and vascular endothelial growth factor alpha at all tested concentrations after 2 days of treatment. In peripheral blood mononuclear cells, 17-ODYA significantly increased the expression of IL-1α, IL-1ß, IL-6, matrix metalloproteinase-1, and monocyte chemoattractant protein-1 at 10 µmol/L (P < .0001) and vascular endothelial growth factor alpha and platelet-derived growth factor alpha at 1 µmol/L 17-ODYA (P < .0001). 17-ODYA polarized macrophages toward a proinflammatory phenotype (M1) and suppressed the release of pro- and anti-inflammatory cytokines. 17-ODYA significantly enhanced the release of IL-8. CONCLUSIONS: This study was the first to identify the pathologic role of 17-ODYA in the development of periapical abscesses. The results of this study are important in shedding light on the pathogenesis of periapical abscesses in relation to microbial metabolites.


Assuntos
Quimiocina CCL2 , Abscesso Periapical , Humanos , Metaloproteinase 1 da Matriz , Interleucina-6 , Leucócitos Mononucleares , Fator A de Crescimento do Endotélio Vascular , Fator de Crescimento Derivado de Plaquetas , Fator de Necrose Tumoral alfa/metabolismo
7.
Int Endod J ; 56(1): 27-38, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36190353

RESUMO

AIMS: Lipopolysaccharides (LPS)-activated human dental pulp stem cells (hDPSCs) and macrophage co-cultures showed downregulated TNF-α secretion that is modulated by hDPSCs through IDO axis, whereas the secretory levels of IL-1ß remained unchanged. Therefore, sustained production of IL-1ß could contribute to progressive dental pulp inflammation. However, the role of interleukin-1 receptor antagonist (IL-1RA) in downregulating the secretion of IL-1ß and TNF-α in LPS-activated M0/M1/M2 macrophage and hDPSCs co-culture has not been studied yet. Therefore, the aim of the present study was to determine the immunomodulatory role of blocking IL-1 receptors in DPSCs macrophage co-culture activated with LPS. METHODOLOGY: Human monocytic cell line THP-1 was polarized to M0, M1 and M2 macrophages and co-cultured with hDPSCs. The viability of the co-cultured cells was assessed by apoptosis assay. Co-cultures were activated with LPS followed by the assessment of gene expression and protein levels of IL-1ß and TNF-α with and without IL-1RA blocking via qRT-PCR and cytokine flex assay by flow cytometry. Data from three separate experiments were analysed using one-way anova followed by Tukey's post hoc test and a p-value of <.05 was considered statistically significant. RESULTS: THP-1-derived M0, M1 and M2 macrophages co-cultured with hDPSCs showed spindle and round-shaped cells, with >90% viability when assessed by apoptosis assay. Inflammatory TNF-α and IL-1ß profiles in stimulated co-cultures showed upregulated IL-1ß, whereas TNF-α was downregulated (p < .05). Anti-inflammatory gene expression levels of IL-10 and TGF-ß were downregulated (p < .05). Blocking with IL-1RA resulted in a remarkable decrease in IL-1ß at the gene expression and protein production levels whilst TNF-α levels remained low (p < .05). Levels of anti-inflammatory cytokine IL-10 showed no significant difference. CONCLUSION: Blocking the IL-1 receptor in hDPSCs and macrophage (M0, M1, M2) co-cultures activated with LPS resulted in downregulation of inflammatory cytokines IL-1ß and TNF-α. These findings highlight the immunomodulatory effect of IL-1RA in inflammatory conditions of dental pulp infections.


Assuntos
Proteína Antagonista do Receptor de Interleucina 1 , Lipopolissacarídeos , Humanos , Proteína Antagonista do Receptor de Interleucina 1/farmacologia , Lipopolissacarídeos/farmacologia , Técnicas de Cocultura , Interleucina-10 , Fator de Necrose Tumoral alfa , Polpa Dentária , Macrófagos , Anti-Inflamatórios , Células-Tronco
8.
Biochem Biophys Res Commun ; 631: 138-145, 2022 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-36183555

RESUMO

High serum ferritin (hyperferritinemia), a reliable hallmark of severe COVID-19 often associates with a moderate decrease in serum iron (hypoferremia) and a moderate increase in serum hepcidin. This suggests that hyperferritinemia in severe COVID-19 is reflective of inflammation rather than iron overload. To test this possibility, the expression status of ferritin heavy chain (FTH1), transferrin receptor 1 (TFRC), hepcidin (HAMP), and ferroportin (SLC40A1) genes and promoter methylation status of FTH1 and TFRC genes were examined in blood samples obtained from COVID-19 patients showing no, mild or severe symptoms and in healthy-donor monocytes stimulated with SARS-CoV-2-derived peptides. Severe COVID-19 samples showed a significant increase in FTH1 expression and hypomethylation relative to mild or asymptomatic COVID-19 samples. S-peptide treated monocytes also showed a significant increase in FTH1 expression and hypomethylation relative to that in controls; treatment with ECD or NP did not change FTH1 expression nor its methylation status. In silico and in vitro analysis showed a significant increase in the expression of the TET3 demethylase in S peptide-treated monocytes. Findings presented here suggest that S peptide-driven hypomethylation of the FTH1 gene promoter underlies hyperferritinemia in severe COVID-19 disease.


Assuntos
COVID-19 , Hiperferritinemia , Apoferritinas/genética , COVID-19/genética , Metilação de DNA , Ferritinas/metabolismo , Hepcidinas/genética , Hepcidinas/metabolismo , Humanos , Ferro/metabolismo , Oxirredutases/metabolismo , Receptores da Transferrina , SARS-CoV-2
9.
Horm Metab Res ; 54(8): 562-566, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35724687

RESUMO

In the aftermath of the corona pandemic, long-COVID or post-acute COVID-19 syndrome still represents a great challenge, and this topic will continue to represent a significant health problem in the coming years. At present, the impact of long-COVID on our health system cannot be fully assessed but according to current studies, up to 40% of people who have been infected with SARS-CoV-2 suffer from clinically relevant symptoms of long-COVID syndrome several weeks to months after the acute phase. The main symptoms are chronic fatigue, dyspnea, and various cognitive symptoms. Initial studies have shown that people with overweight and diabetes mellitus have a higher risk of developing long-COVID associated symptoms. Furthermore, repeated treatment of acute COVID-19 and long-COVID with steroids can contribute to long-term metabolic and endocrine disorders. Therefore, a structured program with rehabilitation and physical activity as well as optimal dietary management is of utmost importance, especially for patients with metabolic diseases and/or long-COVID. Furthermore, the removal of autoantibodies and specific therapeutic apheresis procedures could lead to a significant improvement in the symptoms of long-COVID in individual patients.


Assuntos
COVID-19 , Doenças do Sistema Endócrino , COVID-19/complicações , Doenças do Sistema Endócrino/complicações , Doenças do Sistema Endócrino/epidemiologia , Doenças do Sistema Endócrino/terapia , Humanos , Pandemias , SARS-CoV-2 , Síndrome de COVID-19 Pós-Aguda
10.
Front Microbiol ; 13: 863133, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35387075

RESUMO

Secreted fungal peptides are known to influence the interactions between the pathogen and host innate immunity. The aim of this study is to screen and evaluate secreted peptides from the fungus Rhizopus arrhizus var. delemar for their immunomodulatory activity. By using mass spectrometry and immuno-informatics analysis, we identified three secreted peptides CesT (S16), Colicin (S17), and Ca2+/calmodulin-dependent protein kinase/ligand (CAMK/CAMKL; S27). Culturing peripheral blood-derived monocytic macrophages (PBMMs) in the presence of S16 or S17 caused cell clumping, while culturing them with S27 resulted in the formation of spindle-shaped cells. S27-treated PBMMs showed cell cycle arrest at G0 phase and exhibited alternatively activated macrophage phenotype with pronounced reduction in scavenger receptors CD163 and CD206. Homology prediction indicated that IL-4/IL-13 is the immunomodulatory target of S27. Confirming this prediction, S27 initiated macrophage activation through phosphorylation of STAT-6; STAT-6 inhibition reversed the activity of S27 and reduced the formation of spindle-shaped PBMMs. Lastly, S27 treatment of PBMMs was associated with altered expression of key iron regulatory genes including hepcidin, ferroportin, transferrin receptor 1, and ferritin in a pattern consistent with increased cellular iron release; a condition known to enhance Rhizopus infection. Collectively, R. arrhizus var. delemar secretes peptides with immunomodulatory activities that support fungal pathogenesis. Targeting the IL-4/IL-13R/STAT-6 axis is a potential therapeutic approach to enhance the PBMM-mediated fungal phagocytosis. This represents a potential new approach to overcome lethal mucormycosis.

12.
Arch Pharm (Weinheim) ; 354(9): e2100120, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34085721

RESUMO

Medicinal plants are valuable sources of different active constituents that are known to have important pharmacological activities including anticancer effects. Lupeol, a pentacyclic triterpenoid, present in many medicinal plants, has a wide range of biological activities. Although the anticancer activity of lupeol was reported, the published data are inconsistent and the clear mechanism of action has never been assigned. The current study aims at investigating the anticancer specificity and mechanism of lupeol isolated from Avicennia marina, which grows in the desert of the United Arab Emirates. The compound was purified by chromatography and identified by spectroscopy. Compared with a negative control, lupeol caused significant (p < .001) growth inhibitory activity on MCF-7 and Hep3B parental and resistant cells by 45%, 46%, 72%, and 35%, respectively. The mechanism of action of lupeol was further explored by measuring its effect on key players in cancer development and progression, BCL-2 anti-apoptotic and BAX pro-apoptotic proteins. Lupeol significantly (p < .01) downregulated BCL-2 gene expression in parental and resistant Hep3B cells by 33 and 3.5 times, respectively, contributing to the induction of apoptosis in Hep3B cells, whereas it caused no effect on BAX. Furthermore, the immunoblotting analysis revealed that lupeol cleaved the executioner caspase-3 into its active form. Interestingly, lupeol showed no significant effect on the proliferation of monocytes, whereas it caused an increase in the sub-G1 population and a reduction in the apoptosis rates of monocytes at 48 and 72 h, indicative of no immuno-inflammatory responses. Collectively, lupeol can be considered as promising effective and safe anticancer agent, particularly against Hep3B cancer cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Avicennia/química , Triterpenos Pentacíclicos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Feminino , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Células MCF-7 , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Triterpenos Pentacíclicos/isolamento & purificação , Proteínas Proto-Oncogênicas c-bcl-2/genética , Fatores de Tempo
13.
Pharmaceuticals (Basel) ; 13(7)2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32645833

RESUMO

Brain metastases represent one of the incurable end stages in breast cancer (BC). Developing effective or preventive treatments is hampered by a lack of knowledge on the molecular mechanisms driving brain metastasis. Transmigration of BC cells through the brain endothelium is a key event in the pathogenesis of brain metastasis. In this study, we identified miR-101-3p as a critical micro-RNA able to reduce transmigration of BC cells through the brain endothelium. Our results revealed that miR-101-3p expression is downregulated in brain metastatic BC cells compared to less invasive variants, and varies inversely compared to the brain metastatic propensity of BC cells. Using a loss-and-gain of function approach, we found that miR-101-3p downregulation increased transmigration of BC cells through the brain endothelium in vitro by inducing COX-2 expression in cancer cells, whereas ectopic restoration of miR-101-3p exerted a metastasis-reducing effect. In regulatory experiments, we found that miR-101-3p mediated its effect by modulating COX-2-MMP1 signaling capable of degrading the inter-endothelial junctions (claudin-5 and VE-cadherin), key components of the brain endothelium. These findings suggest that miR-101-3p plays a critical role in the transmigration of breast cancer cells through the brain endothelium by modulating the COX-2-MMP1 signaling and thus may serve as a therapeutic target that can be exploited to prevent or suppress brain metastasis in human breast cancer.

14.
Biochem J ; 477(13): 2489-2507, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32538426

RESUMO

Melanin is a dark color pigment biosynthesized naturally in most living organisms. Fungal melanin is a major putative virulence factor of Mucorales fungi that allows intracellular persistence by inducing phagosome maturation arrest. Recently, it has been shown that the black pigments of Rhizopus delemar is of eumelanin type, that requires the involvement of tyrosinase (a copper-dependent enzyme) in its biosynthesis. Herein, we have developed a series of compounds (UOSC-1-14) to selectively target Rhizopus melanin and explored this mechanism therapeutically. The compounds were designed based on the scaffold of the natural product, cuminaldehyde, identified from plant sources and has been shown to develop non-selective inhibition of melanin production. While all synthesized compounds showed significant inhibition of Rhizopus melanin production and limited toxicity to mammalian cells, only four compounds (UOSC-1, 2, 13, and 14) were selected as promising candidates based on their selective inhibition to fungal melanin. The activity of compound UOSC-2 was comparable to the positive control kojic acid. The selected candidates showed significant inhibition of Rhizopus melanin but not human melanin by targeting the fungal tyrosinase, and with an IC50 that are 9 times lower than the reference standard, kojic acid. Furthermore, the produced white spores were phagocytized easily and cleared faster from the lungs of infected immunocompetent mice and from the human macrophages when compared with wild-type spores. Collectively, the results suggested that the newly designed derivatives, particularly UOSC-2 can serve as promising candidate to overcome persistence mechanisms of fungal melanin production and hence make them accessible to host defenses.


Assuntos
Produtos Biológicos/metabolismo , Melaninas/biossíntese , Rhizopus/química , Ativação Enzimática/efeitos dos fármacos , Humanos , Melaninas/metabolismo , Estrutura Molecular , Monofenol Mono-Oxigenase/metabolismo , Fagocitose/fisiologia , Pironas/farmacologia , Relação Estrutura-Atividade
15.
Biol Trace Elem Res ; 194(2): 560-569, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31267442

RESUMO

Over recent years, metal nanoparticles have largely been investigated due to their potential activities. This study focused on synthesizing silver nanoparticles (AgNPs) using the desert plant Cyperus conglomeratus, which is the most abundant species on the sand dunes in the UAE, and their anticancer activity. The synthesized AgNPs were characterized using UV-visible spectra, X-ray diffraction, energy dispersive X-ray spectroscopy, fourier transform infrared spectroscopy, dynamic light scattering, and scanning electron microscope. The results showed that the AgNPs are monodispersed and mostly spherical in shape. The cytotoxicity effects were investigated against breast cancer cells MCF-7 and normal fibroblast using MTT assay which showed selective cytotoxicity against MCF-7 with an IC50 at 5 µg/mL but not fibroblast. Moreover, the apoptotic effects were confirmed using annexin V-FITC-PI double staining kit and real-time PCR for apoptotic genes. Therefore, our results revealed potential anticancer applications of the C. conglomeratus biosynthesized silver nanoparticles.


Assuntos
Antineoplásicos , Neoplasias da Mama , Cyperus , Nanopartículas Metálicas , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos , Células MCF-7 , Extratos Vegetais/farmacologia , Prata/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
16.
J Neurotrauma ; 36(24): 3410-3421, 2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31232176

RESUMO

Spinal cord injury (SCI) has devastating consequences, with limited therapeutic options; therefore, improving its functional outcome is a major goal. The outcome of SCI is contributed to by neuroinflammation, which may be a target for improved recovery and quality of life after injury. Macrophage inhibitory cytokine-1/growth differentiation factor 15 (MIC-1/GDF15) has been identified as a potential novel therapy for central nervous system (CNS) injury because it is an immune regulatory cytokine with neurotrophic properties. Here we used MIC-1/GDF15 knockout (KO) and overexpressing/transgenic (Tg) and wild type (WT) animals to explore its putative therapeutic benefits in a mouse model of contusive SCI. MIC-1/GDF15 Tg mice had superior locomotor recovery and reduced secondary tissue loss at 28 days compared with their KO and WT counterparts. Overexpression of MIC-1/GDF15 coincided with increased expression of monocyte chemoattractant protein-1 (MCP-1)/C-C Motif Chemokine Ligand 2 (CCL2) at the lesion site (28 days post-SCI) and enhanced recruitment of inflammatory cells to the injured spinal cord. This inflammatory cellular infiltrate included an increased frequency of macrophages and dendritic cells (DCs) that mostly preceded recruitment of cluster of differentiation (CD)4+ and CD8+ T cells. Collectively, our findings suggest hat MIC-1/GDF15 is associated with beneficial changes in the clinical course of SCI that are characterized by altered post-injury inflammation and improved functional outcome. Further investigation of MIC-1/GDF15 as a novel therapeutic target for traumatic SCI appears warranted.


Assuntos
Fator 15 de Diferenciação de Crescimento/biossíntese , Recuperação de Função Fisiológica/fisiologia , Traumatismos da Medula Espinal/metabolismo , Animais , Feminino , Expressão Gênica , Fator 15 de Diferenciação de Crescimento/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/patologia , Vértebras Torácicas/lesões
17.
Diabetes Res Clin Pract ; 153: 166-175, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31150725

RESUMO

AIM: Excessive visceral adiposity is a major risk factor for developing insulin resistance and systemic low-grade inflammation. Ramadan diurnal fasting (RDF) is a religious ritual practiced by more than one billion Muslim throughout the world. It has been considered as one of the most common types of complementary and integrative health practices. The aim of this study is to examine the impact of RDF on visceral adiposity, circulating adipokines and glucoregulatory markers in patients with overweight or obesity. METHODS: Overweight and obese subjects (n = 61; 23 men and 38 women) were included in the study. Body weight, visceral fat tissue area (measured by 3D-MRI), glucoregulatory factors, serum adipokines concentrations, dietary intake, and physical activity were assessed one week before and at the end of the lunar month of Ramadan. RESULTS: From baseline, body weight and visceral fat tissue area serum total cholesterol, triglycerides, HDL-cholesterol, and systolic blood pressure significantly decreased (P < 0.05 for each) at the end of Ramadan. The serum levels of adiponectin, IL-6, TNF-α, and IGF-1 significantly decreased (P < 0.05 for each), but serum visfatin, leptin, apelin, IL-10, and IL-10/IL-6 ratio significantly increased (P < 0.05 for each) at the end of Ramadan. Changes in visceral adiposity significantly correlated with changes in plasma glucose (r = 0.4, P < 0.5) and resistin (r = 0.44, P < 0.001) at the end of Ramadan. CONCLUSION: RDF lowers visceral adiposity, body weight and variably affects adipokines without adversely affecting markers of glucose homeostasis in individuals with overweight or obesity.


Assuntos
Adipocinas/sangue , Adiposidade/fisiologia , Jejum , Obesidade/sangue , Sobrepeso/sangue , Adulto , Feminino , Humanos , Islamismo , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
18.
PLoS One ; 13(2): e0192576, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29415032

RESUMO

Unlike animals, plants are sessile organisms, lacking circulating antibodies and specialized immune cells and are exposed to various harsh environmental conditions that make them at risk of being attacked by different pathogens and herbivores. Plants produce chemo-signals to respond to the surroundings and be able to distinguish between harmless and harmful signals. In this study, the production of phytochemicals as plant signaling mechanisms and their defensive roles in disease resistance and repelling herbivores are examined in Calligonum comosum. C. comosum is a leafless standalone perennial shrub widespread in sand dunes. The plant has the ability to survive the drastic environmental conditions of the arid/ hyperarid deserts of the Arabia. Structural anatomy and phytochemicals analyses were used to identify both mechanical and chemical defensive mechanisms in C. comosum. Microscopy-based investigations indicated that stems of this species developed hard structures in its outer layers including sclerenchyma and cluster crystals of calcium oxalate (CaOx). Sclerenchyma and CaOx are difficult to be eaten by herbivores and insects and can harm their mouthparts. On the other hand, the plant developed both short-distance (local) and long-distance (systematic over limited sphere) phytochemicals-producing cells located at its outer regions that is surrounding the inner nutrient-rich vascular system (VS). Local chemical was represented by phenolic idioblasts that were released in response to plant cutting. Systematic chemical was represented by toxic volatile oil containing ~50% benzaldehyde derivative (cuminaldehyde). The oil caused strong killing effect on both mammalian cells and microbial pathogens via either direct addition or indirect exposure to its vapor. The plants lost the oil content and allowed fungal growth once cut and dried. The localization of both defensive mechanisms to the outer region of the plant seemed to protect the inner nutrient-rich VS and hence maintained the plant survival. Surprisingly, in relation to traditional folklore use as medicine, local people use only green parts of the plant and only during the winter, where the plant found devoid of volatile oil and phenolic idioblasts. Moreover, it turns into recommendations for local people to avoid any health problems caused by the plant supply.


Assuntos
Clima Desértico , Polygonaceae/fisiologia , Polygonaceae/anatomia & histologia , Polygonaceae/metabolismo
19.
PLoS One ; 10(2): e0115189, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25695521

RESUMO

The divergent TGF-ß superfamily member, macrophage inhibitory cytokine-1 (MIC-1/GDF15), is overexpressed by most cancers, including prostate cancer (PCa). Whilst its circulating levels are linked to cancer outcome, the role MIC-1/GDF15 plays in cancer development and progression is incompletely understood. To investigate its effect on PCa development and spread, we have used TRAMP prostate cancer prone mice bearing a germline deletion of MIC-1/GDF15 (TRAMPMIC-/-). On average TRAMPMIC-/- mice died about 5 weeks earlier and had larger prostatic tumors compared with TRAMP mice that were wild type for MIC-1/GDF15 (TRAMPMIC+/+). Additionally, at the time of death or ethical end point, even when adjusted for lifespan, there were no significant differences in the number of mice with metastases between the TRAMPMIC+/+ and TRAMPMIC-/- groups. However, consistent with our previous data, more than twice as many TRAMP mice overexpressing MIC-1/GDF15 (TRAMPfmsmic-1) had metastases than TRAMPMIC+/+ mice (p<0.0001). We conclude that germ line gene deletion of MIC-1/GDF15 leads to increased local tumor growth resulting in decreased survival consistent with an overall protective role for MIC-1/GDF15 in early primary tumor development. However, in advancing disease, as we have previously noted, MIC-1/GDF15 overexpression may promote local invasion and metastatic spread.


Assuntos
Fator 15 de Diferenciação de Crescimento/deficiência , Fator 15 de Diferenciação de Crescimento/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Animais , Deleção de Genes , Fator 15 de Diferenciação de Crescimento/genética , Masculino , Camundongos , Camundongos Transgênicos , Neoplasias da Próstata/genética
20.
J Clin Invest ; 124(3): 1228-41, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24569378

RESUMO

In the CNS, no pathway dedicated to immune surveillance has been characterized for preventing the anti-CNS immune responses that develop in autoimmune neuroinflammatory disease. Here, we identified a pathway for immune cells to traffic from the brain that is associated with the rostral migratory stream (RMS), which is a forebrain source of newly generated neurons. Evaluation of fluorescently labeled leukocyte migration in mice revealed that DCs travel via the RMS from the CNS to the cervical LNs (CxLNs), where they present antigen to T cells. Pharmacologic interruption of immune cell traffic with the mononuclear cell-sequestering drug fingolimod influenced anti-CNS T cell responses in the CxLNs and modulated experimental autoimmune encephalomyelitis (EAE) severity in a mouse model of multiple sclerosis (MS). Fingolimod treatment also induced EAE in a disease-resistant transgenic mouse strain by altering DC-mediated Treg functions in CxLNs and disrupting CNS immune tolerance. These data describe an immune cell pathway that originates in the CNS and is capable of dampening anti-CNS immune responses in the periphery. Furthermore, these data provide insight into how fingolimod treatment might exacerbate CNS neuroinflammation in some cases and suggest that focal therapeutic interventions, outside the CNS have the potential to selectively modify anti-CNS immunity.


Assuntos
Movimento Celular , Células Dendríticas/fisiologia , Tolerância Imunológica , Prosencéfalo/imunologia , Animais , Antígenos CD11/metabolismo , Células Cultivadas , Encefalomielite Autoimune Experimental/induzido quimicamente , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Feminino , Cloridrato de Fingolimode , Linfonodos/imunologia , Linfonodos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pescoço , Propilenoglicóis , Prosencéfalo/patologia , Esfingosina/análogos & derivados , Linfócitos T Reguladores/imunologia
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