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1.
J Asian Nat Prod Res ; 26(6): 739-746, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38329008

RESUMO

A new flavonolignan, sonyamandin (1), along with other known compounds was isolated from the aerial parts and seeds extracts of Silybum marianum (milk thistle) collected from Jordan. The known ones are ursolic acid (2), oleanolic acid (3), maslinic acid (4), oleic acid (5), ß-sitosterol (6), ß-, sitosteryl glucoside (7), apigenin (8), kaempferol-3-O-rhamnoside (9), apigenin-7-O-ß-D-glycoside (10), isosylibin A (11), isosylibin B (12), and silybin B (13). The absolute stereochemistry of 1 was confirmed by 2D NMR and CD analysis.


Assuntos
Flavonolignanos , Silybum marianum , Silybum marianum/química , Estrutura Molecular , Flavonolignanos/química , Flavonolignanos/isolamento & purificação , Jordânia , Sementes/química , Ressonância Magnética Nuclear Biomolecular , Sitosteroides/química , Ácido Oleanólico/química , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/isolamento & purificação , Apigenina/química , Triterpenos/química , Triterpenos/isolamento & purificação
2.
J Clin Invest ; 133(21)2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37651197

RESUMO

The triggering receptor expressed on myeloid cell 1 (TREM1) plays a critical role in development of chronic inflammatory disorders and the inflamed tumor microenvironment (TME) associated with most solid tumors. We examined whether loss of TREM1 signaling can abrogate the immunosuppressive TME and enhance cancer immunity. To investigate the therapeutic potential of TREM1 in cancer, we used mice deficient in Trem1 and developed a novel small molecule TREM1 inhibitor, VJDT. We demonstrated that genetic or pharmacological TREM1 silencing significantly delayed tumor growth in murine melanoma (B16F10) and fibrosarcoma (MCA205) models. Single-cell RNA-Seq combined with functional assays during TREM1 deficiency revealed decreased immunosuppressive capacity of myeloid-derived suppressor cells (MDSCs) accompanied by expansion in cytotoxic CD8+ T cells and increased PD-1 expression. Furthermore, TREM1 inhibition enhanced the antitumorigenic effect of anti-PD-1 treatment, in part, by limiting MDSC frequency and abrogating T cell exhaustion. In patient-derived melanoma xenograft tumors, treatment with VJDT downregulated key oncogenic signaling pathways involved in cell proliferation, migration, and survival. Our work highlights the role of TREM1 in cancer progression, both intrinsically expressed in cancer cells and extrinsically in the TME. Thus, targeting TREM1 to modify an immunosuppressive TME and improve efficacy of immune checkpoint therapy represents what we believe to be a promising therapeutic approach to cancer.


Assuntos
Melanoma , Células Supressoras Mieloides , Humanos , Animais , Camundongos , Receptor Gatilho 1 Expresso em Células Mieloides/genética , Receptor Gatilho 1 Expresso em Células Mieloides/metabolismo , Células Mieloides/patologia , Linhagem Celular Tumoral , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/metabolismo , Linfócitos T Citotóxicos/patologia , Modelos Animais de Doenças , Microambiente Tumoral
3.
Hum Immunol ; 84(8): 366-373, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36934068

RESUMO

Despite the growing interest in the role of regulatory B cells (Bregs) in autoimmunity, their distinct role and function in kidney transplant outcomes remain elusive. Here, we retrospectively analyzed the proportion of Bregs, transitional Bregs (tBregs) and memory Bregs (mBregs) and their capacity to produce IL-10 in non-rejected (NR) versus rejected (RJ) kidney transplant recipients. In the NR group, we observed a significant increase in the proportion of mBregs (CD19+CD24hiCD27+) but no difference in tBregs (CD19+CD24hiCD38+), as compared to the RJ group. We also observed a significant increase in IL-10-producing mBregs (CD19+CD24hiCD27+IL-10+) in the NR group. As our group and others have previously reported a potential role of the human leukocyte antigen G (HLA-G) in human renal allograft survival, notably through IL-10, we then investigated possible crosstalk between HLA-G and IL-10+ mBregs. Our ex vivo data suggest a role of HLA-G in enhancing IL-10+ mBreg expansion upon stimulation, which further decreased CD3+ T cell proliferation capability. Using RNA-sequencing (RNA-seq), we identified potential key signaling pathways involved in HLA-G-driven IL-10+ mBreg expansion, such as the MAPK, TNF and chemokine signaling pathways. Together, our study highlights a novel HLA-G-mediated IL-10-producing mBreg pathway that may serve as a therapeutic target to improve kidney allograft survival.


Assuntos
Linfócitos B Reguladores , Transplante de Rim , Humanos , Antígenos HLA-G/metabolismo , Interleucina-10/metabolismo , Estudos Retrospectivos , Rim , Aloenxertos
4.
Microbiol Spectr ; 10(5): e0112622, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36190414

RESUMO

Infection of C57BL/6 wild-type mice with Leishmania major 5-ASKH or Friedlin strains results in relatively similar pathogenicity with self-healing lesions within weeks. Parasite clearance depends on nitric oxide production by activated macrophages in response to cytokines produced mainly by CD4+ Th1 cells. In contrast, C57BL/6 Rag2 knockout mice, which lack T and B lymphocytes, show distinct pathologies during infection with these strains. Despite of the similar parasite number, the 5-ASKH infection induced severe inflammation rather than the Friedlin. To determine the immunological factors behind this phenomenon, we infected C57BL/6 Rag2 knockout mice with these two strains and compared immune cell kinetics and macrophage activation status. Compared with the Friedlin strain, the 5-ASKH strain elicited increased pathology associated with the accumulation of CD11bhigh, Ly6Ghigh neutrophils by week four and increased the expression of macrophage activation markers. We then analyzed the differentially expressed transcripts in infected bone marrow-derived macrophages by RNA sequencing. It showed upregulation of multiple inflammatory transcripts, including Toll-like receptor 1/2 (TLR1/2), CD69, and CARD14, upon 5-ASKH infection. Our findings suggest that different L. major strains can trigger distinct macrophage activation, contributing to the disease outcome observed in the absence of lymphocytes but not in the presence of lymphocytes. IMPORTANCE Disease manifestations of cutaneous leishmaniasis (CL) range from self-healing cutaneous lesions to chronic forms of the disease, depending on the infecting Leishmania sp. and host immune protection. Previous works on mouse models of CL show the distinct pathogenicity of Leishmania major strains in the absence of lymphocytes. However, the mechanisms of this pathology remain uncovered. In the trial to understand the immunological process involved in lymphocyte-independent pathology, we have found a specific induction of macrophages by different L. major strains that affect their ability to mount innate responses leading to neutrophilic pathology when lymphocytes are ablated.


Assuntos
Leishmania major , Leishmaniose Cutânea , Camundongos , Animais , Receptor 1 Toll-Like , Ativação de Macrófagos , Virulência , Óxido Nítrico , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/patologia , Camundongos Knockout , Citocinas , Células Th1
5.
BMJ Open ; 10(12): e036320, 2020 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-33268398

RESUMO

OBJECTIVE: To determine the association of prenatal exposure to intimate partner violence (IPV) with birth weight as a continuous variable among term births in a Nigerian population. DESIGN: Cross-sectional study. SETTING: Mother-child pairs recruited when their newborns were brought for BCG or other vaccines shortly after birth at the Child Welfare Clinic of Barau Dikko Teaching Hospital, Kaduna, Nigeria. PARTICIPANTS: 293 women with term birth infants. MAIN EXPOSURE AND OUTCOME MEASURES: Emotional, physical and sexual IPV were measured postnatally by interview using the Conflict Tactics Scale. Birth weight in grams was the main outcome measure. Linear regression, with adjustment for covariates, was used to estimate associations between birth weight and exposure to the presence, and frequency, of IPV. RESULTS: Sixty-seven per cent of mothers experienced at least one of the three forms of IPV during pregnancy. Relative to the 33% of women with no prenatal exposure to any form of IPV, we observed a reduction in birth weight of 94 g (95% CI: -202 to 15) for prenatal exposure to emotional IPV, 162 g (95% CI -267 to -58) for physical IPV and 139 g (95% CI -248 to -30) for sexual IPV. The combination of all three forms of IPV was associated with a 223 g reduction in birth weight (95% CI -368 to -77). Increasing occurrences of each of the three types of IPV were associated with greater reductions in birth weight. For physical IPV, relative to no exposure to any form of IPV, birth weight was lower by 112 g (95% CI -219 to -4) with 1-5 instances and 380 g (95% CI -553 to -206) for >5 instances over the pregnancy. CONCLUSIONS: Maternal exposure to IPV was associated with shifting of the birth weight distribution among term newborns. A dose-response relationship was observed between frequency of IPV and birth weight.


Assuntos
Violência por Parceiro Íntimo , Nascimento a Termo , Peso ao Nascer , Criança , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Nigéria , Gravidez
6.
Nat Commun ; 11(1): 3461, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-32651371

RESUMO

Leishmaniasis is a neglected tropical disease caused by Leishmania protozoa transmitted by infected sand flies. Vaccination through leishmanization with live Leishmania major has been used successfully but is no longer practiced because it resulted in occasional skin lesions. A second generation leishmanization is described here using a CRISPR genome edited L. major strain (LmCen-/-). Notably, LmCen-/- is a genetically engineered centrin gene knock-out mutant strain that is antibiotic resistant marker free and does not have detectable off-target mutations. Mice immunized with LmCen-/- have no visible lesions following challenge with L. major-infected sand flies, while non-immunized animals develop large and progressive lesions with a 2-log fold higher parasite burden. LmCen-/- immunization results in protection and an immune response comparable to leishmanization. LmCen-/- is safe since it is unable to cause disease in immunocompromised mice, induces robust host protection against vector sand fly challenge and because it is marker free, can be advanced to human vaccine trials.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Leishmania major/genética , Leishmania major/patogenicidade , Vacinas Atenuadas/uso terapêutico , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Dexametasona/farmacologia , Feminino , Citometria de Fluxo , Edição de Genes , Engenharia Genética , Humanos , Terapia de Imunossupressão , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Psychodidae/parasitologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
Steroids ; 128: 15-22, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29037584

RESUMO

Derivatives of spironolactone (1), a diuretic and antihypertensive drug, were synthesized by using fungal cells for the first time. Ten different fungi were screened for their ability to biotransform 1, four of which were able to produce metabolites 2-8. Gibberella fujikuroi produced canrenone (2), 1-dehydrocanrenone (3), Curvularia lunuta provided compound 2, and 7α-thio-spironolactone (4), Fusarium lini yielded compounds 2, 3, 1ß-hydroxycanrenone (5), 1α-hydroxycanrenone (6), 1-dehydro-15α-hydroxycanrenone (7), and 15α-hydroxycanrenone (8), while Aspergillus alliaceus was able to produce all the seven metabolites. Metabolites 5, 6, and 7 were identified as new compounds. Their structures were elucidated by using different spectroscopic techniques. Substrate 1 and its metabolites 2, 3, and 5-8 were also evaluated for α-glucosidase inhibitory activity in vitro. Substrate 1 was found to be strongly active with IC50 = 335 ±â€¯4.3 µM as compared to the standard drug acarbose IC50 = 840 ±â€¯1.73 µM, whereas all of resulting metabolites were found to be inactive.


Assuntos
Anti-Hipertensivos/síntese química , Biotransformação , Diuréticos/síntese química , Espironolactona/síntese química , Anti-Hipertensivos/química , Anti-Hipertensivos/uso terapêutico , Ascomicetos/química , Ascomicetos/genética , Ascomicetos/metabolismo , Aspergillus/química , Aspergillus/genética , Aspergillus/metabolismo , Diuréticos/química , Diuréticos/uso terapêutico , Fusarium/química , Fusarium/genética , Fusarium/metabolismo , Gibberella/química , Gibberella/genética , Gibberella/metabolismo , Humanos , Estrutura Molecular , Espironolactona/análogos & derivados , Espironolactona/química , Espironolactona/uso terapêutico
8.
mBio ; 7(1): e02102-15, 2016 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-26758185

RESUMO

UNLABELLED: Recent studies suggest small intestine bacterial overgrowth (SIBO) is common among developing world children. SIBO's pathogenesis and effect in the developing world are unclear. Our objective was to determine the prevalence of SIBO in Bangladeshi children and its association with malnutrition. Secondary objectives included determination of SIBO's association with sanitation, diarrheal disease, and environmental enteropathy. We performed a cross-sectional analysis of 90 Bangladeshi 2-year-olds monitored since birth from an impoverished neighborhood. SIBO was diagnosed via glucose hydrogen breath testing, with a cutoff of a 12-ppm increase over baseline used for SIBO positivity. Multivariable logistic regression was performed to investigate SIBO predictors. Differences in concomitant inflammation and permeability between SIBO-positive and -negative children were compared with multiple comparison adjustment. A total of 16.7% (15/90) of the children had SIBO. The strongest predictors of SIBO were decreased length-for-age Z score since birth (odds ratio [OR], 0.13; 95% confidence interval [CI], 0.03 to 0.60) and an open sewer outside the home (OR, 4.78; 95% CI, 1.06 to 21.62). Recent or frequent diarrheal disease did not predict SIBO. The markers of intestinal inflammation fecal Reg 1ß (116.8 versus 65.6 µg/ml; P = 0.02) and fecal calprotectin (1,834.6 versus 766.7 µg/g; P = 0.004) were elevated in SIBO-positive children. Measures of intestinal permeability and systemic inflammation did not differ between the groups. These findings suggest linear growth faltering and poor sanitation are associated with SIBO independently of recent or frequent diarrheal disease. SIBO is associated with intestinal inflammation but not increased permeability or systemic inflammation. IMPORTANCE: A total of 165 million children worldwide are considered stunted, which is associated with increased risk of death prior to age 5 years and cognitive disability. Stunting has, in part, been attributed to the presence of environmental enteropathy. Environmental enteropathy is a poorly understood condition leading to chronic intestinal inflammation. It has been postulated that small intestine bacterial overgrowth contributes to the pathogenesis of environmental enteropathy as overgrowth has been associated with intestinal inflammation and micronutrient malabsorption when it develops in other clinical contexts. This study confirms the finding that overgrowth occurs at high rates in the developing world. This is the first study to show that overgrowth is associated with intestinal inflammation and linear growth delay in this setting and is the first to examine why children with no known gastrointestinal dysfunction develop overgrowth from the developing world environment.


Assuntos
Síndrome da Alça Cega/epidemiologia , Síndrome da Alça Cega/patologia , Exposição Ambiental , Intestino Delgado/patologia , Desnutrição/complicações , Bangladesh/epidemiologia , Criança , Estudos Transversais , Fezes/química , Humanos , Complexo Antígeno L1 Leucocitário/análise , Litostatina/análise , Pobreza , Prevalência , Fatores de Risco
9.
Fitoterapia ; 81(7): 864-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20580923

RESUMO

Two new withanolides named mandragorolide A (1) and mandragorolide B (2) were isolated from the MeOH extract of the whole plant of Mandragora officinarum of Jordanian origin, along with five known withanolides namely larnaxolide A (3), withanolide B (4), datura lactone 2 (5), withanicandrin (6) and salpichrolide C (7). Compound 3 has been reported only once before, from the leaves of Larnax glabra. This is the first report of withanolides of different biogenetic types from the genus Mandragora. Isolation of known fatty compounds, coumarins, sterols and tropane alkaloids was also achieved in this study.


Assuntos
Mandragora/química , Extratos Vegetais/química , Vitanolídeos/isolamento & purificação , Jordânia , Estrutura Molecular , Extratos Vegetais/isolamento & purificação , Vitanolídeos/química
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