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1.
Sci Rep ; 14(1): 6533, 2024 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503773

RESUMO

Nitrogen (N) and phosphorus (P) are vital for crop growth. However, most agricultural systems have limited inherent ability to supply N and P to crops. Biochars (BCs) are strongly advocated in agrosystems and are known to improve the availability of N and P in crops through different chemical transformations. Herein, a soil-biochar incubation experiment was carried out to investigate the transformations of N and P in two different textured soils, namely clay loam and loamy sand, on mixing with rice straw biochar (RSB) and acacia wood biochar (ACB) at each level (0, 0.5, and 1.0% w/w). Ammonium N (NH4-N) decreased continuously with the increasing incubation period. The ammonium N content disappeared rapidly in both the soils incubated with biochars compared to the unamended soil. RSB increased the nitrate N (NO3-N) content significantly compared to ACB for the entire study period in both texturally divergent soils. The nitrate N content increased with the enhanced biochar addition rate in clay loam soil until 15 days after incubation; however, it was reduced for the biochar addition rate of 1% compared to 0.5% at 30 and 60 days after incubation in loamy sand soil. With ACB, the net increase in nitrate N content with the biochar addition rate of 1% remained higher than the 0.5% rate for 60 days in clay loam and 30 days in loamy sand soil. The phosphorus content remained consistently higher in both the soils amended with two types of biochars till the completion of the experiment.


Assuntos
Compostos de Amônio , Poluentes do Solo , Solo/química , Fósforo , Areia , Argila , Nitratos , Nitrogênio , Carvão Vegetal/química , Poluentes do Solo/análise
2.
Cell Death Dis ; 14(9): 599, 2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37679334

RESUMO

Deletion of TRAF2 or TRAF3 in B cells prolongs their survival. However, it remains unknown whether deletion of such factors affects B cells' ability to tolerate DNA damage, which can be induced by chemotherapeutics and cause apoptosis. Genetic alterations of TRAF2 or TRAF3 are observed in subsets of human B-cell lymphomas and B cell-specific deletion of TRAF3 led to lymphoma development in aged mice. However, it remains unknown whether double deficiency of TRAF2 and TRAF3 accelerates B-cell lymphomagenesis. Here, we showed that B cell-specific TRAF2/3 double deficient (B-TRAF2/3-DKO) B cells were remarkably more resistant to DNA damage-induced apoptosis via upregulating cIAP2 and XIAP, which in turn attenuates caspase-3 activation. Mechanistically, resistance to DNA damage-induced apoptosis required NF-κB2, which effects by upregulating XIAP and cIAP2 transcription. B-TRAF2/3-DKO mice exhibited a shorter lifespan and succumbed to splenomegaly and lymphadenopathy. Unexpectedly, the incidence of B-cell lymphoma development in B-TRAF2/3-DKO mice was relatively rare (∼10%). Sequencing B cell receptor repertoire of diseased B cells revealed that TRAF2/3 deficiency caused abnormal oligoclonal or clonal expansion of B cells. While a fraction of mutant B cells (25-43%) from aged diseased mice harbored recurrent chromosomal translocations, primary B cells isolated from young B-TRAF2/3-DKO mice had no detectable chromosomal alterations, suggesting that TRAF2/3 deficiency per se does not cause evident genomic instability in B cells. Chemo-resistant TRAF3-deficient B-cell lymphomas were sensitized to chemotherapeutic drugs by blocking IAP activity using IAP antagonist. We conclude that double deficiency of TRAF2 and TRAF3 does not accelerate B-cell lymphomagenesis. Our studies provide insight into mechanisms regulating DNA damage-induced apoptosis and may help develop effective therapies targeting mutant B-cell lymphomas using IAP antagonist.


Assuntos
Linfoma de Células B , Linfoma , Humanos , Animais , Camundongos , Idoso , Fator 2 Associado a Receptor de TNF/genética , Fator 3 Associado a Receptor de TNF/genética , Subunidade p52 de NF-kappa B , Apoptose/genética , Dano ao DNA , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X
3.
Front Immunol ; 14: 1100520, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37051229

RESUMO

Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment; however, the responses to ICI treatment are highly variable in different individuals and the underlying mechanisms remain poorly understood. Here, we employed a mouse squamous cell carcinoma (SCC) model where tumor-bearing recipients diverged into responders (R) versus non-responders (NR) upon anti-PD-L1 treatment. We performed in-depth TCRß sequencing with immunoSEQ platform to delineate the differences in CD8 tumor-infiltrating lymphocytes (TILs). We found that R and NR CD8 TILs both exhibited evidence of clonal expansion, suggesting activation regardless of response status. We detected no differences in clonal expansion or clonal diversity indexes between R vs. NR. However, the top expanded (>1%) TCRß clonotypes appeared to be mutually exclusive between R and NR CD8 TILs, showing a preferential expansion of distinct TCRß clonotypes in response to the same SCC tumor in R vs. NR. Notably, the mutual exclusivity of TCR clonotypes in R vs. NR was only observed when top TCRß clonotypes were counted, because such top-expanded clonotypes are present in the opposite outcome group at a much lower frequency. Many TCRß sequences were detected in only one recipient at a high frequency, implicating highly individualized anti-tumor immune responses. We conclude that differences in the clonal frequency of top TCR clonotypes between R and NR CD8 TILs may be one of the factors underlying differential anti-PD-L1 responses. This notion may offer a novel explanation for variable ICI responses in different individuals, which may substantially impact the development of new strategies for personalized cancer immunotherapy.


Assuntos
Linfócitos T CD8-Positivos , Imunoterapia , Animais , Camundongos , Receptores de Antígenos de Linfócitos T
4.
Front Immunol ; 13: 992630, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36330507

RESUMO

Differential responses to immune checkpoint inhibitors (ICI) may be attributed to tumor-intrinsic factors or environmental cues; however, these mechanisms cannot fully explain the variable ICI responses in different individuals. Here, we investigate the potential contribution of immunological heterogeneity with a focus on differences in T-cell receptor (TCR) repertoire to ICI responses, which has not been defined previously. To reveal additional factors underlying heterogeneous responses to ICI, we employed a squamous cell carcinoma (SCC) mouse model in which tumor-bearing recipients unambiguously diverged into responders (R) or non-responders (NR) upon anti-PD-L1 treatment. Treatment efficacy absolutely required CD8 T-cells and correlated positively with effector functions of CD8 tumor-infiltrating lymphocytes (TILs). We showed that TCR repertoires exhibited a similar magnitude of clonal expansion in R vs. NR CD8 TILs. However, the top expanded TCR clonotypes appeared to be mutually exclusive between R and NR CD8 TILs, which also occurred in a recipient-specific manner, demonstrating preferential expansion of distinct TCR clonotypes against the same SCC tumor. Unexpectedly, R vs. NR CD8 TILs reached all activation clusters and did not exhibit substantial global differences in transcriptomes. By linking single-cell transcriptomic data with unique TCR clonotypes, CD8 TILs harboring top TCR clonotypes were found to occupy distinct activation clusters and upregulate genes favoring anti-tumor immunity to different extents in R vs. NR. We conclude that stochastic differences in CD8 TIL TCR repertoire and distinct activation states of top TCR clonotypes may contribute to differential anti-PD-L1 responses. Our study suggests that host-intrinsic immunological heterogeneity may offer a new explanation for differential ICI responses in different individuals, which could impact on strategies for personalized cancer immunotherapy.


Assuntos
Carcinoma de Células Escamosas , Linfócitos do Interstício Tumoral , Camundongos , Animais , Linfócitos T CD8-Positivos , Ativação Linfocitária , Receptores de Antígenos de Linfócitos T/genética
5.
Biotechnol Lett ; 42(8): 1383-1395, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32333257

RESUMO

OBJECTIVES: Granulosa cells are associated with steroidogenesis and ovarian function in females. Aims of the study are to understand the effects of gold nanoparticles (AuNP) on steroidogenesis and apoptotic pathway associated genes in buffalo granulosa cells. RESULTS: The AuNP were prepared chemically and thereby characterized by transmission electron microscope (TEM) imaging, absorbance and dynamic light scattering (DLS) measurements for hydrodynamic diameter and zeta potential. The cultured buffalo granulosa cells (BGC) were co-incubated with AuNP in two concentrations (2 × 109 and 2 × 1010 AuNP/ml) for 24 h. Treatment of BGC with AuNP significantly modulated the steroidogenesis associated genes (3ß-Hsd and Cyp19A1) expression and progesterone accumulation in the culture fluid. AuNP affected the apoptotic pathway in BGC by affecting the gene expression of Caspase-3, Bad and Bax. The AuNP did not exert oxidative stress through anti-oxidant induction & lipid peroxidation in the buffalo GC. CONCLUSIONS: AuNP may modulate the endocrine system by having impact on the steroidogenesis pathway and also have the potential to affect apoptotic pathway in a buffalo granulosa cell model.


Assuntos
Apoptose/efeitos dos fármacos , Ouro/farmacologia , Células da Granulosa/efeitos dos fármacos , Nanopartículas Metálicas/química , Progesterona/metabolismo , 3-Hidroxiesteroide Desidrogenases/metabolismo , Animais , Aromatase/metabolismo , Búfalos , Células Cultivadas , Feminino , Ouro/química , Células da Granulosa/metabolismo , Modelos Biológicos
6.
J Cell Biochem ; 119(2): 1488-1500, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28771796

RESUMO

Curcumin possesses anti-inflammatory properties and provides a promising treatment for inflammation. The aim of the study is to establish that buffalo granulosa cells when primed with curcumin (20 µM), release improved cellular contents through exosome that can mitigate granulosa cell dysfunction. Recently, we have shown that buffalo granulosa cells exposed to LPS (1 µg/mL) in serum free culture, transiently increased the pro-inflammatory cytokine genes (IL-1ß, TNF-α, IL-6) expression followed by the inhibition of CYP19A1 gene expression and estradiol production. Therefore, LPS-treated granulosa cells were used as a model of inflammation and curcumin primed exosomes were utilized to check their potential for reducing granulosa cell dysfunction. Expression level of pro-inflammatory cytokines and CYP19A1 were detected by real time PCR while estradiol levels were measured by ELISA. Exosomes derived from curcumin-treated cells alleviated LPS mediated inflammation. In conclusion, our study potentiates the use of curcumin primed exosomes in mitigating granulosa cell dysfunction. Results show the therapeutic conservatories of curcumin via primed exosomes.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Curcumina/farmacologia , Citocinas/genética , Exossomos/metabolismo , Células da Granulosa/imunologia , Lipopolissacarídeos/efeitos adversos , Animais , Aromatase/genética , Búfalos , Células Cultivadas , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Células da Granulosa/citologia , Interleucina-1beta/genética , Interleucina-6/genética , Fator de Necrose Tumoral alfa/genética
7.
Appl Biochem Biotechnol ; 183(3): 993-1007, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28466459

RESUMO

Exosomes, the extracellular secretary nano-vesicles, act as carriers of biomolecules to the target cells. They exhibit several attributes of an efficient drug delivery system. Curcumin, despite having numerous bioactive and therapeutic properties, has limited pharmaceutical use due to its poor water solubility, stability, and low systemic bioavailability. Hence, this study aims to enhance the therapeutic potential of curcumin, a model hydrophobic drug, by its encapsulation into milk exosomes. In the present study, we investigated the stability of free curcumin and exosomal curcumin in PBS and in vitro digestive processes. Additionally, their uptake and trans-epithelial transport were studied on Caco-2 cells. Curcumin in milk exosomes had higher stability in PBS, sustained harsh digestive processes, and crossed the intestinal barrier than free curcumin. In conclusion, the encapsulation of curcumin into the exosomes enhances its stability, solubility, and bioavailability. Therefore, the present study demonstrated that milk exosomes act as stable oral drug delivery vehicles.


Assuntos
Curcumina/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Exossomos/metabolismo , Mucosa Intestinal/metabolismo , Leite/citologia , Animais , Células CACO-2 , Cápsulas , Curcumina/química , Digestão , Humanos , Intestinos/fisiologia , Permeabilidade , Solubilidade
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