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1.
J Med Virol ; 96(5): e29629, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38682607

RESUMO

To inform surveillance, prevention, and management strategies for the varicella zoster virus (VZV) during the COVID-19 pandemic, this study aimed to evaluate the risk of herpes zoster (HZ) occurrence/recurrence following COVID-19 infection and vaccination. A comprehensive search across seven databases was conducted up to January 31, 2024, to identify studies relevant to the occurrence of HZ following COVID-19 infection and vaccination. The meta-analysis included five studies on postinfection HZ and 13 studies on postvaccination HZ. Patients infected with COVID-19 had a 2.16-fold increased risk of HZ (95% confidence interval [CI]: 1.24-3.76) than uninfected individuals. However, there was no significant association between COVID-19 vaccination and the risk of HZ compared to controls, with a relative risk (RR) of 1.08 (95% CI: 0.84-1.39). Furthermore, a descriptive analysis of 74 postinfection and 153 postvaccination HZ studies found no significant differences on gender or age (<50 and ≥50 years) following COVID-19 infection. Notably, 44.0% of the HZ cases postinfection appeared within the first week, with 69.5% resolving within 10 days, predominantly presenting as skin lesions. In the postvaccination group, the majority (60.1%) developed HZ after the first dose and 66.7% occurred within 1 week. Moreover, 44.6% resolved within 10 days and 50.0% within a month, primarily exhibiting skin lesions and postherpetic neuralgia. The study found that COVID-19 infection increases the risk of HZ, but the COVID-19 vaccine does not. Further study is needed to explore the association between COVID-19 and HZ.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Herpes Zoster , Recidiva , Vacinação , Humanos , Herpes Zoster/epidemiologia , Herpes Zoster/prevenção & controle , COVID-19/prevenção & controle , COVID-19/epidemiologia , Vacinação/estatística & dados numéricos , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/administração & dosagem , SARS-CoV-2/imunologia , Herpesvirus Humano 3/imunologia , Pessoa de Meia-Idade , Feminino
2.
Prev Med ; 178: 107817, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38097139

RESUMO

OBJECTIVE: Allostatic load can reflect the body's response to chronic stress. However, little is known about the association between allostatic load and risk of breast cancer in postmenopausal women. This study used a large prospective cohort in the United States to examine the relationship between allostatic load and invasive breast cancer risk, and to evaluate the relationship by racial and ethnic identity and breast cancer subtypes. METHODS: Among 161,808 postmenopausal participants in Women's Health Initiative, eligible were a subsample of 27,393 postmenopausal women aged 50-79 years old, who enrolled from 1993 to 1998, had serum test biomarkers, and were followed for breast cancer incidence through February 2022. Allostatic load at enrollment was computed based on eight biomarkers from lab serum tests and a questionnaire about participants' prescription drug use. The associations between allostatic scores and risk of breast cancer (overall and by subtypes) were assessed using Cox proportional hazards models. The race and ethnic differences were examined. RESULTS: Over a median follow-up time of 17.24 years, 1722 invasive breast cancer cases were identified. High allostatic load was associated with an increased risk of breast cancer (HR = 1.36, 95%CI: 1.20, 1.54 for third tertile vs first tertile, Ptrend < 0.0001). Similar trends were found in White women and non-Hispanic women. Higher allostatic load was associated with hormone receptor-positive and HER2/Neu-negative breast cancer (HR = 1.54, 95%CI: 1.30, 1.80 for third tertile vs first tertile, Ptrend < 0.0001). CONCLUSION: In this study, we found that higher allostatic load was significantly associated with an increased risk of breast cancer in postmenopausal women.


Assuntos
Alostase , Neoplasias da Mama , Feminino , Humanos , Estados Unidos/epidemiologia , Pessoa de Meia-Idade , Idoso , Neoplasias da Mama/epidemiologia , Alostase/fisiologia , Pós-Menopausa , Estudos Prospectivos , Biomarcadores
3.
J Proteome Res ; 22(3): 802-811, 2023 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-36716354

RESUMO

Multitarget bioactive molecules (MBMs) are of increasing importance in drug discovery as they could produce high efficacy and a low chance of resistance. Several advanced approaches of quantitative proteomics were developed to accurately identify the protein targets of MBMs, but little study has been carried out in a sequential manner to identify primary protein targets (PPTs) of MBMs. This set of proteins will first interact with MBMs in the temporal order and play an important role in the mode of action of MBMs, especially when MBMs are at low concentrations. Herein, we describe a valuable observation that the result of the enrichment process is highly dependent on concentrations of the probe and the proteome. Interestingly, high concentrations of probe and low concentrations of incubated proteome will readily miss the hyper-reactive protein targets and thereby increase the probability of rendering PPTs with false-negative results, while low concentrations of probe and high concentrations of incubated proteome more than likely will capture the PPTs. Based on this enlightening observation, we developed a proof-of-concept approach to identify the PPTs of iodoacetamide, a thiol-reactive MBM. This study will deepen our understanding of the enrichment process and improve the accuracy of pull-down-guided target identification.


Assuntos
Proteoma , Proteoma/metabolismo , Descoberta de Drogas
4.
Bioorg Med Chem Lett ; 93: 129414, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37494974

RESUMO

Artemisinin is an endoperoxide bond-containing sesquiterpene lactone showing potent antimalarial effect as well as antitumor and antivirus activities. Inspired by this unique pharmacorphore, researchers around the world developed numerous Artemisinin derivatives. Among these derivatives, the C-10 carba analogues of artemisinin are frequently reported. However, the stereochemistry of C-10 carba analogues of artemisinin is overlooked and the corresponding mixture of stereoisomers are used. Herein, we reported for the first time stereochemistry and antimalarial activity of C-10 carba analogues of artemisinin. We employed two approaches to obtain the pure isomer of C-10 carba analogues and presented an interesting observation about their antimalarial activities. The minor isomer with large-sized substitute and S configuration at C-10 position had much lower antimalarial effect than the major isomer with R configuration. The study will shed light on the development of effective antimalarial drugs based on ART.


Assuntos
Antimaláricos , Artemisininas , Antimaláricos/farmacologia , Artemisininas/farmacologia , Estereoisomerismo
5.
Microbiol Immunol ; 67(2): 79-89, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36345699

RESUMO

A well preserved immune system is a powerful tool to prevent foreign invasion or to suppress internal mutation, which must be tightly controlled by co-stimulatory molecules in different pathophysiological conditions. One such critical molecule is OX40L expressed on activated antigen-presenting cells (APCs). Consistently, its abnormality is associated with various immunological disorders such as autoinflammatory diseases and allergy. However, a comprehensive analysis of the immune-moderating role of OX40L in dendritic cells (DCs), the most powerful APCs to initiate immune responses in vivo, and investigation of its anti-tumor efficacy in the disease setting have not been performed properly. In this study, genetic approaches for both gain-of-function and reduction-of-function were employed to reveal that OX40L was required for the efficient presentation, but not uptake, of antigens by DCs to stimulate CD4+ , as well as CD8+ T cells in vivo. As a result, CD4+ T cells were promoted towards Th1, but inhibited on Treg differentiation, by the LPS-induced OX40L on DCs, which was supported by their altered expression of co-inhibitory receptor, PD-L1. CD8+ T cells, on the other hand, also enhanced their cytotoxicity towards target cells in response to OX40L expression on the DCs transferred in vivo. Finally, in a DC-mediated tumor immunity model, the strong immunogenic roles of OX40L on DCs led to better metastasis inhibition in vivo. Collectively, our results demonstrate that OX40L could serve as a potential target in the DC-based vaccine for enhanced anti-tumor efficacy in vivo.


Assuntos
Linfócitos T CD8-Positivos , Células Dendríticas , Camundongos , Animais , Ativação Linfocitária
6.
Ann Clin Microbiol Antimicrob ; 22(1): 80, 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37679777

RESUMO

BACKGROUND: Chlamydia psittaci (C. psittaci) causes parrot fever in humans. Development of metagenomic next-generation sequencing (mNGS) enables the identification of C. psittaci. METHODS: This study aimed to determine the epidemiological and clinical characteristics of parrot fever cases in China. A multi-center observational study was conducted in 44 tertiary and secondary hospitals across 14 provinces and municipalities between April 2019 and October 2021. RESULTS: A total of 4545 patients with complicated or atypical pulmonary infection were included in the study, among which the prevalence of C. psittaci was determined to be 2.1% using mNGS. The prevalence of C. psittaci was further determined across demographic groups and types of specimens. It was significantly higher in patients with senior age (2.6% in those > 50 years), winter-spring (3.6%; particularly in December, January, and February), and southwestern (3.4%) and central and southern China (2.7%) (each P < 0.001). Moreover, the prevalence was the highest in bronchoalveolar lavage fluid (BALF) (2.9%), compared with sputum (1.1%) and peripheral blood specimens (0.9%). Additionally, co-infection of principal microorganisms was compared. Certain microorganisms were more likely to co-infect in parrot fever cases, such as Candida albicans in BALF (26.7%) and peripheral blood (6.3%), compared with non-parrot fever cases (19.7% and 1.3%); however, they did not significantly differ (each P > 0.05). CONCLUSION: Parrot fever remains low in patients with complicated or atypical pulmonary infection. It is likely to occur in winter-spring and southwestern region in China. BALF may be the optimal specimen in the application of mNGS. Co-infection of multiple microorganisms should be further considered.


Assuntos
Coinfecção , Pneumonia , Psitacose , Humanos , Pessoa de Meia-Idade , Psitacose/diagnóstico , Psitacose/epidemiologia , Sequenciamento de Nucleotídeos em Larga Escala , Candida albicans , China/epidemiologia , Pneumonia/epidemiologia
7.
Plant J ; 105(4): 1113-1122, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33225500

RESUMO

Despite the availability of numerous molecular markers in maize, effective evaluation of all types of germplasm resources, accurate identification of varieties and analysis of a large number of materials in a timely, low-cost manner is challenging. Here, we present Maize6H-60K, a genome-wide single nucleotide polymorphism (SNP) array to facilitate maize genotyping. We first identified 160 million variants by sequencing data of 388 representative inbreds and then tiled 200 000 high-quality variants on a screening array. These variants were further narrowed down to 61 282 using stringent filtering criteria. Among the 60 000 markers, 21 460 SNPs (35%) were within genic regions and 12 835 (21%) were located in coding regions. To assess their effectiveness, 329 inbreds, 221 hybrids, 34 parent-offspring sets and six breeding samples were genotyped. Overall, 48 972 SNPs (80%) were categorized into the highest quality class, that of 'poly high resolution'. A total of 54 658 (89.29%) and 53 091 (86.73%) SNPs had minor allele frequency values ≥ 0.20 in inbreds and hybrids respectively. A linkage disequilibrium (LD) analysis revealed that LD decline was in equilibrium when r2 was between 0.10 and 0.15, which corresponds to a physical distance of 400-600 kb. UPGMA clustering analysis divided the 329 inbred lines into nine groups that were consistent with known pedigrees. A background analysis of breeding materials indicated that the 60 000 markers were suitable for evaluation of breeding populations constructed by materials between or within heterotic groups. The developed Maize6H-60K array should be an important tool in maize genetic studies, variety identification and molecular breeding.


Assuntos
Polimorfismo de Nucleotídeo Único/genética , Zea mays/genética , DNA de Plantas/genética , DNA de Plantas/isolamento & purificação , Frequência do Gene/genética , Marcadores Genéticos/genética , Genoma de Cloroplastos/genética , Técnicas de Genotipagem , Análise de Sequência com Séries de Oligonucleotídeos , Sequenciamento Completo do Genoma
8.
Cancer Causes Control ; 33(12): 1413-1419, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36129619

RESUMO

PURPOSE: The incidence of triple-negative breast cancer (TNBC) is higher in Black women compared to White women which is not explained by racial differences in body mass index (BMI). As BMI has limitations as an anthropometric measure, we used different anthropometric measures to examine associations with TNBC by race. METHOD: Of 161,808 postmenopausal participants in Women's Health Initiative, eligible were a subsample of 121,744 White and Black postmenopausal women enrolled from 1993 to 1998, 50-79 years of age with anthropometric measures who were followed for breast cancer incidence until March 2019. At entry, BMI, waist circumference (WC), and waist-hip ratio (WHR) were measured using standardized methods. Breast cancers were verified by central medical record review. Associations between anthropometric measures and triple-negative breast cancer risk were examined using Cox proportional hazards regression models. RESULTS: After 17.6 years (median) follow-up, there were 87 Black women and 529 White women with incident triple-negative breast cancer. Overall, there were no significant associations between anthropometric measures and risk of triple-negative breast cancer. However, compared to White women with normal BMI, White women with obesity (BMI ≥ 30) (HR 0.76, 95% CI 0.60, 0.96) were significantly associated with a lower risk of triple-negative breast cancer. And larger waist circumference (HR per centimeter 0.99, 95% CI 0.99, 1.00) was significantly associated with a lower risk of triple-negative breast cancer among White women. CONCLUSION: Overall, among postmenopausal women, anthropometric measures were not associated with risk of TNBC. The association among White women with larger waist circumference and women with obesity with a lower risk of triple-negative breast cancer needs further confirmation.


Assuntos
Neoplasias de Mama Triplo Negativas , Feminino , Humanos , Neoplasias de Mama Triplo Negativas/epidemiologia , Fatores Raciais , Pós-Menopausa , Estudos Prospectivos , Relação Cintura-Quadril , Circunferência da Cintura , Índice de Massa Corporal , Fatores de Risco , Obesidade/complicações , Obesidade/epidemiologia
9.
Clin Exp Hypertens ; 44(4): 334-340, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35343343

RESUMO

BACKGROUND: At present, pre-eclampsia is a growing concern and still a diagnostic challenge for obstetricians. AIMS: This study aimed to evaluate whether the relationship of second trimester of pregnancy neutrophil count differed among pregnancies with mild preeclampsia, severe preeclampsia, and healthy status and explore whether or not neutrophil count in the second trimester of pregnancy would be useful as new predictors of subsequent preeclampsia. PATIENTS AND METHODS: This study involved 933 pregnancies from 1 January 2018 to 30 January 2021, comprising 396 healthy pregnancies, 222 pregnancies with mild preeclampsia, and 315 pregnancies with severe preeclampsia. The relationship between preeclampsia and neutrophil count was analyzed by multiple logistic regression. In addition, maternal placental tissues of three groups were immunohistochemically stained for myeloperoxidase (MPO). RESULTS: Neutrophil count was significantly higher in pregnancies with preeclampsia (including pregnancies with mild and severe preeclampsia) than that in healthy pregnancies. The neutrophil count level was prominently higher in patients with severe preeclampsia compared with those with mild preeclampsia (p < .001). The neutrophil count level was significantly positively associated with preeclampsia after adjusting for gestational week at time of blood sampling, BMI, and age (ß:1.23; 95%CI:1.09-1.36; p < .0001). In addition, MPO expressions of placental tissues in preeclamptic groups were significantly increased than these in healthy pregnant controls (p < .05). CONCLUSIONS: Increased neutrophil count in the second trimester of pregnancy was significantly positively associated with preeclampsia. Hence, neutrophil count plays a role in predicting the severity of preeclampsia. At the same time, it may be an independent predictor of subsequent preeclampsia.Abbreviations: BMI: body mass index; MPO: myeloperoxidase.


Assuntos
Pré-Eclâmpsia , Gravidez , Humanos , Feminino , Pré-Eclâmpsia/diagnóstico , Peroxidase , Placenta , Segundo Trimestre da Gravidez , Estudos de Casos e Controles
10.
BMC Bioinformatics ; 22(1): 429, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34496768

RESUMO

BACKGROUND: With the broad application of high-throughput sequencing and its reduced cost, simple sequence repeat (SSR) genotyping by sequencing (SSR-GBS) has been widely used for interpreting genetic data across different fields, including population genetic diversity and structure analysis, the construction of genetic maps, and the investigation of intraspecies relationships. The development of accurate and efficient typing strategies for SSR-GBS is urgently needed and several tools have been published. However, to date, no suitable accurate genotyping method can tolerate single nucleotide variations (SNVs) in SSRs and flanking regions. These SNVs may be caused by PCR and sequencing errors or SNPs among varieties, and they directly affect sequence alignment and genotyping accuracy. RESULTS: Here, we report a new integrated strategy named the accurate microsatellite genotyping tool based on targeted sequencing (AMGT-TS) and provide a user-friendly web-based platform and command-line version of AMGT-TS. To handle SNVs in the SSRs or flanking regions, we developed a broad matching algorithm (BMA) that can quickly and accurately achieve SSR typing for ultradeep coverage and high-throughput analysis of loci with SNVs compatibility and grouping of typed reads for further in-depth information mining. To evaluate this tool, we tested 21 randomly sampled loci in eight maize varieties, accompanied by experimental validation on actual and simulated sequencing data. Our evaluation showed that, compared to other tools, AMGT-TS presented extremely accurate typing results with single base resolution for both homozygous and heterozygous samples. CONCLUSION: This integrated strategy can achieve accurate SSR genotyping based on targeted sequencing, and it can tolerate single nucleotide variations in the SSRs and flanking regions. This method can be readily applied to divergent sequencing platforms and species and has excellent application prospects in genetic and population biology research. The web-based platform and command-line version of AMGT-TS are available at https://amgt-ts.plantdna.site:8445 and https://github.com/plantdna/amgt-ts , respectively.


Assuntos
Repetições de Microssatélites , Nucleotídeos , Genótipo , Técnicas de Genotipagem , Sequenciamento de Nucleotídeos em Larga Escala , Repetições de Microssatélites/genética
11.
Breast Cancer Res Treat ; 188(1): 283-293, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33677722

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) is disproportionately higher in Black women relative to White women. The objective of this study was to examine to what extent the association between race/ethnicity and risk of TNBC is mediated by potentially modifiable factors. METHODS: A total of 128,623 Black and White women aged 50-79 years from the Women's Health Initiative were followed for a mean of 15.8 years. 643 incident TNBC cases (92 Black women and 551 White women) were confirmed by medical record review. Mediation analyses were conducted using an approach under a counterfactual framework. RESULTS: Black women had approximately twofold higher risk of TNBC compared with white women (HR = 1.93, 95% CI 1.52-2.45). We observed that 48% of the racial disparity was mediated by metabolic dysfunction defined by having 3 or more cardiometabolic risk factors including elevated waist circumference, having history of diabetes, high cholesterol and hypertension. The racial disparity was not significantly mediated by other factors studied, including socioeconomic, lifestyle or reproductive factors. CONCLUSION: Our study observed that approximately half of the racial disparity between postmenopausal Black and White women in TNBC incidence was driven by metabolic dysfunction.


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Feminino , Disparidades nos Níveis de Saúde , Humanos , Incidência , Análise de Mediação , Pós-Menopausa
12.
Arch Gynecol Obstet ; 303(3): 645-652, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33515274

RESUMO

PURPOSE: Our objective of this study was to investigate whether first trimester serum pregnancy-associated plasma protein-A (PAPP-A) differed amongst pregnancies with placenta previa-accreta and non-adherent placenta previa and healthy pregnancies by a retrospective cohort analysis. METHODS: A total of 177 pregnant females were included in the study, as follows: 35 cases of placenta previa-accreta, 30 cases of non-adherent placenta previa, and 112 cases of BMI and age matched, healthy pregnant controls. PAPP-A multiples of the median (MoM) were acquired from laboratory data files in 1 January 2017-30 September 2019. The probable maternal serum biochemical predictor of placenta accreta was analyzed by using multiple logistic regression analysis. RESULTS: PAPP-A MoM of placenta previa-accreta group was significantly higher than those of the non-adherent placenta previa group and control group (p = 0.009 < 0.05, p < 0.001). Serum PAPP-A was found to be significantly positively associated with placenta accreta after adjusted gestational week at time of blood sampling, BMI, age, smoking, and previous cesarean section history (OR: 3.51; 95% CI: 1.77-6.94; p = 0.0003 < 0.05). In addition, smoking (OR: 9.17; 95% CI: 1.69-49.62; p = 0.010 < 0.05) and previous cesarean section history (OR: 2.75; 95% CI: 1.23-6.17; p = 0.014 < 0.05) were also significantly associated with placenta accreta. CONCLUSION: Increased first trimester serum PAPP-A was significantly positively associated with placenta accreta, suggesting that the potential role of PAPP-A in identifying pregnancies at high risk for placenta accreta. Smoking and previous cesarean section history may be the risk factors for accreta in placenta previa patients.


Assuntos
Placenta Acreta/sangue , Placenta Prévia/sangue , Primeiro Trimestre da Gravidez/sangue , Proteína Plasmática A Associada à Gravidez/análise , Adulto , Cesárea , Feminino , Idade Gestacional , Humanos , Gravidez , Proteína Plasmática A Associada à Gravidez/metabolismo , Estudos Retrospectivos , Fatores de Risco
13.
Cell Immunol ; 349: 104049, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32057353

RESUMO

Pathogenic microorganisms utilize multiple approaches to break down host immunity in favor of their invasion, of which, cystatin C is one of the soluble factors secreted by parasites reported to affect host immunity in vivo. The cellular targets and mechanisms of action in vivo of cystatin C, however, are far from clear. As professional antigen-presenting cells, dendritic cells (DCs) are first immune cells that contact foreign pathogenic agents or their products to initiate immune responses. We previously reported that cystatin C can regulate the functions of DCs in terms of suppressed CD4+ T cell activation but enhanced Th1/Th17 differentiation via different mechanisms. Here, we further verified these regulatory effects of cystatin C on DCs in vivo. We found that the suppressive role of DC-mediated CD4+ T cell proliferation by cystatin C was partly cell-contact independent and extended to CD8+ T cells in vivo. Although cystatin C-overexpressing DCs trafficked equally as their mock-transduced counterparts, their adoptive transfer suppressed CD8+ T cell immunity and resulted in compromised tumor rejection in both vaccination and treatment regimes. Compared with their role in promoting Th17 differentiation in vivo, cystatin C-transduced DCs had far greater ability to induce T regulatory cells (Tregs), leading to collectively a higher Treg/Th17 ratio in an adoptively transferred disease model, and thus relieved Th17-dependent autoimmunity. Collectively, these data demonstrated strong in vivo evidences for immune regulatory roles of cystatin C in DCs and provided theoretical basis for the application of cystatin C-transduced cell therapy in the treatment or remission of certain autoimmune diseases. (246).


Assuntos
Transferência Adotiva , Artrite Experimental/terapia , Doenças Autoimunes/terapia , Cistatina C/fisiologia , Células Dendríticas/imunologia , Evasão Tumoral/imunologia , Transferência Adotiva/efeitos adversos , Animais , Comunicação Celular , Células Cultivadas , Cistatina C/genética , Células Dendríticas/transplante , Regulação para Baixo , Fatores de Transcrição Forkhead/biossíntese , Fatores de Transcrição Forkhead/genética , Granzimas/biossíntese , Granzimas/genética , Imunoterapia Adotiva , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Ativação Linfocitária , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Ovalbumina/imunologia , Proteínas Citotóxicas Formadoras de Poros/biossíntese , Proteínas Citotóxicas Formadoras de Poros/genética , Proteínas Recombinantes/metabolismo , Organismos Livres de Patógenos Específicos , Especificidade do Receptor de Antígeno de Linfócitos T , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/imunologia , Transdução Genética
14.
J Cell Physiol ; 234(6): 8776-8787, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30456817

RESUMO

Brain-derived neurotrophic factor (BDNF) is involved in regulating the growth of ovarian follicles, maturation of the oocyte, and development of the early embryo through its receptor, tyrosine kinase receptor B (TrkB). However, it is still unclear as to how BDNF influences proliferation and steroidogenesis of bovine granulosa cells (GCs). In this paper, we confirmed that BDNF and TrkB were expressed in bovine GCs, and that proliferation and steroidogenesis by bovine GCs were reduced by knockdown of BDNF or inhibition of TrkB. With respect to GC proliferation, BDNF enhanced cellular viability and the percentage of cells in the S phase. BDNF also activated both protein kinase B (PKB, also known as AKT) and the extracellular signal-regulated protein kinase 1/2 (ERK1/2)-signaling pathway. Through the AKT-signaling pathway, BDNF increased the expression of proliferation-related genes, including cyclin A1 (CCNA1), cyclin E2 (CCNE2), cyclin D1 (CCND1), and cyclin-dependent kinase 1 (CDK1). However, through the ERK1/2 signaling pathway, BDNF only increased the expression of CCNA1 and CCNE2. Regarding steroidogenesis by bovine GCs, BDNF promoted progesterone (P 4 ) synthesis, but had no effect on estradiol; it also activated the AKT-signaling pathway and increased the expression of steroidogenesis-related genes, including steroidogenic acute regulatory protein (STAR) and hydroxy-δ-5-steroid dehydrogenase, 3ß- and steroid δ-isomerase 1 (HSD3B1). In summary, our data are the first to show that BDNF promotes the proliferation of bovine GCs through TrkB-AKT and ERK1/2 signaling pathways and increases P4 synthesis by bovine GCs through the TrkB-AKT signaling pathway.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/farmacologia , Células da Granulosa/metabolismo , Progesterona/biossíntese , Animais , Bovinos , Proliferação de Células , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/fisiologia , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Fosforilação , Receptor trkB/genética , Receptor trkB/metabolismo
15.
J Cell Physiol ; 234(8): 14058-14067, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30628054

RESUMO

The brain-derived neurotrophic factor (BDNF) was first recognized for its roles in the peripheral and central nervous systems, and its complex functions on mammalian organs have been extended constantly. However, to date, little is known about its effects on the male reproductive system, including the steroidogenesis of mammals. The purpose of this study was to elucidate the effects of BDNF on testosterone generation of Leydig cells and the underlying mechanisms. We found that BDNF-induced proliferation of TM3 Leydig cells via upregulation of proliferating cell nuclear antigen ( Pcna) and promoted testosterone generation as a result of upregulation of steroidogenic acute regulatory protein ( Star), 3b-hydroxysteroid dehydrogenase ( Hsd3b1), and cytochrome P450 side-chain cleavage enzyme ( Cyp11a1) both in primary Leydig cells and TM3 Leydig cells, which were all attenuated in Bdnf knockdown TM3 Leydig cells. Furthermore, the possible mechanism of testosterone synthesis was explored in TM3 Leydig cells. The results showed that BDNF enhanced extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) phosphorylation, and the effect was disrupted by Bdnf deletion. Moreover, PD98059, a potent selective inhibitor of ERK1/2 activation, compromised BDNF-induced testosterone generation and upregulation of Star, Hsd3b1, and Cyp11a1. The Bdnf knockdown assay, on the other hand, indicated the autocrine effect of BDNF on steroidogenesis in TM3 Leydig cells. On the basis of these results, we concluded that BDNF, acting as an autocrine factor, induced testosterone generation as a result of the upregulation of Star, Hsd3b1, and Cyp11a1 via stimulation of the ERK1/2 pathway.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Fosfoproteínas/genética , Antígeno Nuclear de Célula em Proliferação/genética , Reprodução/genética , Testosterona/biossíntese , Animais , Comunicação Autócrina/genética , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Proliferação de Células/efeitos dos fármacos , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Técnicas de Silenciamento de Genes , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/metabolismo , Sistema de Sinalização das MAP Quinases/genética , Masculino , Camundongos , Complexos Multienzimáticos/genética , Progesterona Redutase/genética , Esteroide Isomerases/genética , Testosterona/genética
16.
Immunol Cell Biol ; 97(10): 916-930, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31513306

RESUMO

Cystatin C is a ubiquitously expressed cysteine protease inhibitor that protects cells from either improper hydrolysis by endogenous proteases or pathogen growth/virulence by exogenous proteases. Although commonly used as a serum biomarker for evaluating renal function, cystatin C is associated with many immunological disorders under various pathophysiological conditions. How cystatin C affects immune cells, especially dendritic cells (DCs), however, is far from clear. In this study, we found that pharmacological treatment with or genetic overexpression of cystatin C in bone marrow-derived DCs (BMDCs) reduced their capacity to stimulate CD4+ T-cell proliferation, despite increased antigen uptake. This reduced capacity corresponded with reduced major histocompatibility complex-II presentation owing to diminished levels of the chaperon H2-DM in BMDCs. Instead of promoting proliferation, cystatin C promoted skewing of T cells toward proinflammatory T-helper (Th)1/Th17 differentiation. This was mediated by augmented extracellular signal-regulated kinase 1/2 mitogen-activated protein kinase phosphorylation in BMDCs, leading to secretion of polarizing cytokines, which in turn led to the Th deviation. Collectively, our study explained the cellular and molecular basis of how this protease inhibitor can regulate immune responses, namely by affecting BMDCs and their cytokine pathway. Our results might open up an avenue for the development of therapeutic agents for the treatment of cystatin C-related immunological diseases.


Assuntos
Apresentação de Antígeno , Células da Medula Óssea/citologia , Cistatina C/metabolismo , Citocinas/biossíntese , Células Dendríticas/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Peptídeos/metabolismo , Animais , Diferenciação Celular , Linhagem Celular , Polaridade Celular , Proliferação de Células , Galinhas , Camundongos Endogâmicos C57BL , Óxido Nítrico/biossíntese , Células Th1/imunologia , Células Th17/imunologia
17.
Reprod Domest Anim ; 54(7): 972-978, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31025395

RESUMO

Follicular cysts, which is a common infertility disease, can cause financial losses in pig breeding programmes. The pathogenesis and mechanisms of the formation of follicular cysts are not understood clearly. In our previous study, the concentration of retinol-binding protein 4 (RBP-4) in the follicular fluid (FF) of the ovary with follicular cysts was found to be significantly higher than that of normal ovary, thereby suggesting that RBP-4 may be a candidate biomarker for porcine follicular cysts. To study the association of RBP-4 and follicular cysts further, we detected the polymorphisms of the RBP-4 gene and the presence of follicular cysts by PCR-Restriction fragment length polymorphism (RFLP) assay. In this study, we screened the mutations of RBP-4 gene in 79 sows with follicular cysts and 100 normal sows without cysts. Results showed that +249-63G>C polymorphisms were significantly associated with follicular cysts, and sows with CC genotype in RBP-4 gene had a high risk of developing follicular cysts. Hence, our findings further proved that RBP-4 may be a novel biomarker for follicular cysts, which may be valuable for the diagnosis of follicular cysts and molecular breeding of pigs.


Assuntos
Cisto Folicular/veterinária , Proteínas Plasmáticas de Ligação ao Retinol/genética , Doenças dos Suínos/genética , Animais , Biomarcadores , Feminino , Cisto Folicular/genética , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , Sus scrofa , Suínos
18.
Int J Mol Sci ; 20(3)2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30704086

RESUMO

Ammonia is one of the major toxic components of metabolites in blood and tissues of high-producing dairy cows and could affect the health of bovine mammary glands. Bovine mammary epithelial cells are sensitive to oxidative stress induced by intensive cell metabolism. In our previous study, we found that ammonia could induce oxidative stress, apoptosis and inflammatory responses in bovine mammary epithelial cells. In the present study, the cytoprotective effects of astragaloside IV against ammonia in vitro were explored. The results demonstrated that pretreatment of MAC-T cells with astragaloside IV could potently suppress the increase in the level of intracellular reactive oxygen species (ROS) and the rate of cell apoptosis, inhibit the ammonia-induced inflammatory responses, and rescue the decrease of cell viability. Astragaloside IV prevented ammonia-induced endoplasmic reticulum stress. Astragaloside IV also significantly suppressed the levels of BAX, caspase 3 and p53 phosphorylation in ammonia-induced MAC-T cells. Nuclear factor erythroid 2-related factor 2(Nrf2) was essential for cytoprotective effects of astragaloside IV in MAC-T cells, as knockdown of Nrf2 dramatically abolished the prosurvival effects of astragaloside IV on treated cells. Furthermore, the PI3K/AKT and ERK/MAPK pathways were responsible for the induction of Nrf2 by astragaloside IV. In conclusion, astragaloside IV played a beneficial role against ammonia-induced damage of MAC-T cells. This provides a cue for future study to use astragaloside IV as a protective and curative agent against ammonia exposure of mammary glands in dairy cows.


Assuntos
Amônia/farmacologia , Apoptose/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Glândulas Mamárias Humanas/citologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Bovinos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Feminino , Humanos , Fosforilação/efeitos dos fármacos , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Saponinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Triterpenos/farmacologia
19.
Molecules ; 24(2)2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30669661

RESUMO

Endometritis, inflammation of the endometrium, is a common reproductive obstacle disease that can lead to infertility in female animals. Astragaloside IV (AS IV), one of the major and active components of the Astragalus membranaceus (Fisch.) Bunge, is known for its anti-inflammatory effects. In the present study, the effects and mechanisms of AS IV on lipopolysaccharide (LPS)-induced endometritis were investigated using a mouse model. Female mice were prepared with AS IV (0.01 mg/g) by gavage for six days before being stimulated with LPS. The results showed that the histopathological changes, levels of inflammatory cytokines (IL-1ß and TNF-α), concentration of NO, and myeloperoxidase (MPO) activity in LPS-induced uteri were attenuated significantly by pretreatment with AS IV. Furthermore, LPS-induced activations of NF-κB, p38, and JNK signal pathways were suppressed by pretreatment with AS IV. In conclusion, the data provided new evidence that AS IV effectively attenuates LPS-induced endometritis through inhibition of TLR4-mediated NF-κB, p38, and JNK signaling pathways, implying that AS IV might become a promising potential anti-inflammatory agent for endometritis and other inflammatory diseases.


Assuntos
Endometrite/etiologia , Endometrite/metabolismo , Lipopolissacarídeos/efeitos adversos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , NF-kappa B/metabolismo , Substâncias Protetoras/farmacologia , Saponinas/farmacologia , Triterpenos/farmacologia , Animais , Biomarcadores , Citocinas/metabolismo , Endometrite/tratamento farmacológico , Endometrite/patologia , Feminino , Imuno-Histoquímica , Mediadores da Inflamação/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Substâncias Protetoras/química , Saponinas/química , Receptor 4 Toll-Like/metabolismo , Triterpenos/química
20.
Mutagenesis ; 33(4): 291-299, 2018 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-30184101

RESUMO

Ammonia, produced mainly from the deamination of amino acids and glutamine, is one of the major toxic components in blood and tissues that may affect bovine health. However, the physiological and pathological roles of ammonia in the mammary glands are not understood clearly. In the present study, the bovine mammary epithelial cell line (MAC-T) was utilised as an in vitro model to determine the effects of ammonia on bovine mammary gland. We demonstrated that ammonia stimulated the production of intracellular reactive oxygen species, decreased mitochondrial membrane potential, interrupted intracellular calcium ion (Ca2+) homeostasis and induced cell apoptosis. Ammonia also significantly reduced cell viability and increased the proportion of apoptotic cells through enhancing the level of p53 phosphorylation and increasing the expressions of BAX, caspase 8, caspase 9, caspase 3. Interestingly, bumetanide, a specific Na+ K+ 2Cl--cotransporter inhibitor, dramatically abolished the damaging effects of ammonia on the cells. These data suggest that ammonia exposure induces apoptosis in bovine mammary epithelial cells via activation of the p53 pathway and the mitochondrial apoptotic pathway, and that these effects involved the Na+ K+ 2Cl--cotransporter.


Assuntos
Amônia/farmacologia , Apoptose/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Glândulas Mamárias Animais/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Cálcio/metabolismo , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Células Epiteliais/metabolismo , Glândulas Mamárias Animais/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo
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