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1.
FASEB J ; 38(11): e23710, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38822676

RESUMO

Steroidogenic tissues contain cytosolic lipid droplets that are important for steroidogenesis. Perilipin 2 (PLIN2), a structural coat protein located on the surface of lipid droplets in mammalian cells, plays a crucial role in regulating lipid droplet formation and contributing to various cellular processes such as lipid storage and energy homeostasis. Herein, we examine the role that PLIN2 plays in regulating progesterone synthesis in the bovine corpus luteum. Utilizing gene array databases and Western blotting, we have delineated the expression pattern of PLIN2 throughout the follicular to luteal transition. Our findings reveal the presence of PLIN2 in both ovarian follicular and steroidogenic luteal cells, demonstrating an increase in its levels as follicular cells transition into the luteal phase. Moreover, the depletion of PLIN2 via siRNA enhanced progesterone production in small luteal cells, whereas adenovirus-mediated overexpression of both PLIN2 and Perilipin 3 (PLIN3) induced an increase in cytosolic lipid droplet accumulation and decreased hormone-induced progesterone synthesis in these cells. Lastly, in vivo administration of the luteolytic hormone prostaglandin F2α resulted in an upregulation of PLIN2 mRNA and protein expression, accompanied by a decline in serum progesterone. Our findings highlight the pivotal role of PLIN2 in regulating progesterone synthesis in the bovine corpus luteum, as supported by its dynamic expression pattern during the follicular to luteal transition and its responsiveness to luteotropic and luteolytic hormones. We suggest PLIN2 as a potential therapeutic target for modulating luteal function.


Assuntos
Células Lúteas , Perilipina-2 , Progesterona , Animais , Feminino , Bovinos , Progesterona/metabolismo , Perilipina-2/metabolismo , Perilipina-2/genética , Células Lúteas/metabolismo , Gotículas Lipídicas/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Perilipina-3/metabolismo , Corpo Lúteo/metabolismo , Células Cultivadas
2.
bioRxiv ; 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38405789

RESUMO

Progesterone production by the corpus luteum is fundamental for establishing and maintaining pregnancy. The pituitary gonadotropin luteinizing hormone (LH) is recognized as the primary stimulus for luteal formation and progesterone synthesis, regardless of species. Previous studies demonstrated an elevation in abundance of genes related to glucose and lipid metabolism during the follicular to luteal transition. However, the metabolic phenotype of these highly steroidogenic cells has not been studied. Herein, we determined acute metabolic changes induced by LH in primary luteal cells and defined pathways required for progesterone synthesis. Untargeted metabolomics analysis revealed that LH induces rapid changes in vital metabolic pathways, including glycolysis, tricarboxylic acid (TCA) cycle, pentose phosphate pathway, de novo lipogenesis, and hydrolysis of phospholipids. LH stimulated glucose uptake, enhanced glycolysis, and flux of [U- 13 C 6 ]-labeled glucose-derived carbons into metabolic branches associated with adenosine 5'-triphosphate (ATP) and NADH/NADPH production, synthesis of nucleotides, proteins, and lipids, glycosylation of proteins or lipids, and redox homeostasis. Selective use of small molecule inhibitors targeting the most significantly changed pathways, such as glycolysis, TCA cycle, and lipogenesis, uncovered cellular metabolic routes required for LH-stimulated steroidogenesis. Furthermore, LH via the protein kinase A (PKA) pathway triggered post- translational modification of acetyl-CoA carboxylase alpha (ACACA) and ATP citrate lyase (ACLY), enzymes involved in de novo synthesis of fatty acids. Inhibition of ACLY and fatty acid transport into mitochondria reduced LH-stimulated ATP, cAMP production, PKA activation, and progesterone synthesis. Taken together, these findings reveal novel hormone-sensitive metabolic pathways essential for maintaining LHCGR/PKA signaling and steroidogenesis in ovarian luteal cells. Significance: The establishment and maintenance of pregnancy require a well-developed corpus luteum, an endocrine gland within the ovary that produces progesterone. Although there is increased awareness of intracellular signaling events initiating the massive production of progesterone during the reproductive cycle and pregnancy, there are critical gaps in our knowledge of the metabolic and lipidomic pathways required for initiating and maintaining luteal progesterone synthesis. Here, we describe rapid, hormonally triggered metabolic pathways, and define metabolic targets crucial for progesterone synthesis by ovarian steroidogenic cells. Understanding hormonal control of metabolic pathways may help elucidate approaches for improving ovarian function and successful reproduction or identifying metabolic targets for developing nonhormonal contraceptives.

3.
Cell Death Dis ; 15(1): 31, 2024 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212315

RESUMO

Maternal obesity increases the risk of childhood obesity and programs the offspring to develop metabolic syndrome later in their life. Palmitate is the predominant saturated free fatty acid (FFA) that is transported across the placenta to the fetus. We have recently shown that saturated FFA in the maternal circulation as a result of increased adipose tissue lipolysis in third trimester of pregnancy induces trophoblast lipoapoptosis. Here, we hypothesized that palmitate induces integrated stress response by activating mitogen-activated protein kinases (MAPKs), endoplasmic reticulum (ER) stress and granular stress and lipoapoptosis in trophoblasts. Choriocarcinoma-derived third-trimester placental trophoblast-like cells (JEG-3 and JAR) referred as trophoblasts were exposed to various concentrations of palmitate (PA). Apoptosis was assessed by nuclear morphological changes and caspase 3/7 activity. Immunoblot and immunofluorescence analysis was performed to measure the activation of MAPKs, ER stress and granular stress response pathways. Trophoblasts exposed to pathophysiological concentrations of PA showed a concentration-dependent increase in trophoblast lipoapoptosis. PA induces a caspase-dependent trophoblast lipoapoptosis. Further, PA induces MAPK activation (JNK and ERK) via phosphorylation, and activation of ER stress as evidenced by an increased phosphorylation eIF2α & IRE1α. PA also induces the activation of stress granules formation. Two pro-apoptotic transcriptional mediators of PA-induced trophoblast lipoapoptosis, CHOP and FoxO3 have increased nuclear translocation. Mechanistically, PA-induced JNK is critical for trophoblast lipoapoptosis. However, PA-induced activation of ERK and stress granule formation were shown to be cell survival signals to combat subcellular stress due to PA exposure. In conclusion, PA induces the activation of integrated stress responses, among which small molecule inhibition of JNK demonstrated that activation of JNK is critical for PA-induced trophoblast lipoapoptosis and small molecule activation of stress granule formation significantly prevents PA-induced trophoblast lipoapoptosis.


Assuntos
Palmitatos , Obesidade Infantil , Criança , Feminino , Humanos , Gravidez , Palmitatos/farmacologia , Palmitatos/metabolismo , Linhagem Celular Tumoral , Endorribonucleases , Placenta/metabolismo , Proteínas Serina-Treonina Quinases , Apoptose , Proteínas Quinases Ativadas por Mitógeno , Estresse do Retículo Endoplasmático , Trofoblastos/metabolismo
4.
Int J Colorectal Dis ; 38(1): 264, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37932486

RESUMO

PURPOSES: To compare the risk of anastomotic leak (AL) between Ethicon manual circular staplers (two-row) versus Medtronic EEA™ circular stapler with Tri-Staple™ technology (three-row) and between Medtronic EEA™ circular stapler with DST™ Series technology (two-row) versus Tri-Staple™ technology. METHODS: A retrospective cohort study was conducted in adult patients who underwent a left-sided colorectal surgery 2019-2022 in U.S. Premier Healthcare Database to assess the risk of AL within 30 days post-index procedure. The study devices were Ethicon manual circular staplers, Medtronic EEA™ circular stapler with DST™ technology, and Medtronic EEA™ circular stapler with Tri-Staple™ technology. RESULTS: Across 447 hospitals, the cumulative incidences (95% confidence intervals [CI]) of AL within 30 days post-index procedure were 7.78% (6.91-8.74%) among 8337 patients in the Ethicon manual circular stapler cohort, 7.54% (6.87-8.27%) among 7928 patients in the Medtronic EEA™ circular stapler with DST™ technology cohort, and 8.19% (6.57-10.07%) among 1306 patients in the Medtronic EEA™ circular stapler with Tri-Staple™ technology cohort. Comparative analyses revealed no difference comparing Ethicon manual circular staplers with Medtronic EEA™ circular staplers with Tri-Staple™ technology (risk ratio [RR], 0.72; 95% CI, 0.52-1.01) or comparing Medtronic EEA™ circular staplers with DST™ technology to Tri-Staple™ technology (RR, 0.75; 95% CI, 0.53-1.06). CONCLUSION: In this analysis of a large cohort of patients undergoing a left-sided colorectal surgery from a U.S. hospital database, the risk of AL observed with manual two-row circular staplers was similar to that seen with three-row devices. This study affirms the safety of manual two-row circular staplers in colorectal anastomosis.


Assuntos
Fístula Anastomótica , Neoplasias Colorretais , Adulto , Humanos , Fístula Anastomótica/etiologia , Estudos de Coortes , Grampeadores Cirúrgicos/efeitos adversos , Estudos Retrospectivos , Anastomose Cirúrgica/efeitos adversos , Neoplasias Colorretais/cirurgia , Grampeamento Cirúrgico/efeitos adversos
5.
Biol Reprod ; 109(3): 367-380, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37283496

RESUMO

Cyclic regression of the ovarian corpus luteum, the endocrine gland responsible for progesterone production, involves rapid matrix remodeling. Despite fibroblasts in other systems being known for producing and maintaining extracellular matrix, little is known about fibroblasts in the functional or regressing corpus luteum. Vast transcriptomic changes occur in the regressing corpus luteum, among which are reduced levels of vascular endothelial growth factor A (VEGFA) and increased expression of fibroblast growth factor 2 (FGF2) after 4 and 12 h of induced regression, when progesterone is declining and the microvasculature is destabilizing. We hypothesized that FGF2 activates luteal fibroblasts. Analysis of transcriptomic changes during induced luteal regression revealed elevations in markers of fibroblast activation and fibrosis, including fibroblast activation protein (FAP), serpin family E member 1 (SERPINE1), and secreted phosphoprotein 1 (SPP1). To test our hypothesis, we treated bovine luteal fibroblasts with FGF2 to measure downstream signaling, type 1 collagen production, and proliferation. We observed rapid and robust phosphorylation of various signaling pathways involved in proliferation, such as ERK, AKT, and STAT1. From our longer-term treatments, we determined that FGF2 has a concentration-dependent collagen-inducing effect, and that FGF2 acts as a mitogen for luteal fibroblasts. FGF2-induced proliferation was greatly blunted by inhibition of AKT or STAT1 signaling. Our results suggest that luteal fibroblasts are responsive to factors that are released by the regressing bovine corpus luteum, an insight into the contribution of fibroblasts to the microenvironment in the regressing corpus luteum.


Assuntos
Fator 2 de Crescimento de Fibroblastos , Progesterona , Animais , Bovinos , Feminino , Proliferação de Células , Colágeno/metabolismo , Corpo Lúteo/metabolismo , Dinoprosta/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fibroblastos/metabolismo , Luteólise , Progesterona/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
6.
Biol Reprod ; 106(1): 118-131, 2022 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-34726240

RESUMO

A population of cows with excess androstenedione (A4; High A4) in follicular fluid, with follicular arrest, granulosa cell dysfunction, and a 17% reduction in calving rate was previously identified. We hypothesized that excess A4 in the ovarian microenvironment caused the follicular arrest in High A4 cows and that vascular endothelial growth factor A would rescue the High A4 phenotype. In trial 1, prior to culture, High A4 ovarian cortex (n = 9) had greater numbers of early stage follicles (primordial) and fewer later-stage follicles compared to controls (n = 11). Culture for 7 days did not relieve this follicular arrest; instead, High A4 ovarian cortex had increased indicators of inflammation, anti-Mullerian hormone, and A4 secretion compared to controls. In trial 2, we tested if vascular endothelial growth factor A isoforms could rescue the High A4 phenotype. High A4 (n = 5) and control (n = 5) ovarian cortex was cultured with (1) PBS, (2) VEGFA165 (50 ng/mL), (3) VEGFA165B (50 ng/mL), or (4) VEGFA165 + VEGFA165B (50 ng/mL each) for 7 days. Follicular progression increased with VEGFA165 in High A4 cows with greater early primary, primary, and secondary follicles than controls. Similar to trial 1, High A4 ovarian cortex secreted greater concentrations of A4 and other steroids and had greater indicators of inflammation compared to controls. However, VEGFA165 rescued steroidogenesis, oxidative stress, and fibrosis. The VEGFA165 and VEGFA165b both reduced IL-13, INFα, and INFß secretion in High A4 cows to control levels. Thus, VEGFA165 may be a potential therapeutic to restore the ovarian steroidogenic microenvironment and may promote folliculogenesis.


Assuntos
Androstenodiona/análise , Anovulação/veterinária , Doenças dos Bovinos/tratamento farmacológico , Inflamação/tratamento farmacológico , Folículo Ovariano/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/administração & dosagem , Androstenodiona/metabolismo , Animais , Anovulação/tratamento farmacológico , Anovulação/fisiopatologia , Hormônio Antimülleriano/metabolismo , Bovinos , Citocinas/metabolismo , Feminino , Fibrose , Líquido Folicular/química , Folículo Ovariano/fisiopatologia , Ovário/metabolismo , Ovário/patologia , Estresse Oxidativo/efeitos dos fármacos , Isoformas de Proteínas/administração & dosagem , Técnicas de Cultura de Tecidos/veterinária
7.
J Bone Joint Surg Am ; 103(17): 1637-1645, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34014860

RESUMO

BACKGROUND: Proximal femoral fractures are often treated with cephalomedullary nails. Although nail breakages following fracture repair are infrequent, a recent implant retrieval study suggested that the TFN-ADVANCED (TFNA) Proximal Femoral Nailing System (DePuy Synthes) was susceptible to post-implant breakage. It is unclear whether the risk of breakage among patients who receive the TFNA implant is higher than patients who receive other comparable cephalomedullary nails. The current study was designed to evaluate the comparative risk of breakage of the TFNA nail. METHODS: Using data from a large U.S. health-care database, the current study was designed to determine whether TFNA nails have equal, lower, or higher risk of breakage relative to all other comparable, single-head-element (with no additional lag screws), cephalomedullary nails, the Stryker Gamma3 and the Zimmer Natural Nail, referred to in this study as the non-TFNA group. Data were from patients who received the TFNA implant or non-TFNA nails in 365 hospitals between February 1, 2014, and September 30, 2019. Analysis of nail breakage post-implantation was prespecified as the difference between the TFNA group and the non-TFNA group in cumulative incidence at 18 months, with a prespecified equivalence margin of 0.5%, using data balanced on measured covariates by propensity score weighting. RESULTS: Within the first 18 months of implantation, in 14,370 patients with TFNA nails, there were 27 nail breakages, and in 8,260 patients with non-TFNA nails, there were 29 nail breakages. The mean time to nail breakage was 4.72 months for the TFNA group and 4.05 months for the non-TFNA group. In the balanced data, the risk of breakage at 18 months was 0.26% (95% confidence interval [CI], 0.17% to 0.36%) for the TFNA group and 0.25% (95% CI, 0.05% to 0.45%) for the non-TFNA group, with a risk difference of 0.01% (95% CI, -0.21% to 0.24%). This result indicates that the cumulative incidence of nail breakage was equivalent (between -0.5% and 0.5%) for both nail groups. The risk differences were also within the equivalence margin in subgroup analyses: pertrochanteric fractures only (-0.08% [95% CI, -0.34% to 0.19%]), pertrochanteric or subtrochanteric fractures (-0.04% [95% CI, -0.29% to 0.21%]), and those with International Classification of Diseases, Tenth Revision (ICD-10) data only (0.03% [95% CI, -0.18% to 0.25%]). CONCLUSIONS: The risk of nail breakage was equivalent for TFNA and comparator cephalomedullary nails. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Pinos Ortopédicos/efeitos adversos , Fraturas do Quadril/cirurgia , Falha de Prótese , Idoso , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pontuação de Propensão , Risco , Fatores de Tempo , Estados Unidos
8.
Eur J Ophthalmol ; 31(6): 2938-2946, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33530727

RESUMO

OBJECTIVE: To predict post-operative depth of focus (DoF) using machine learning techniques after cataract surgery with Tecnis Symfony implantation and determine associated impact factors. METHODS: This was a retrospective cohort study among patients receiving Tecnis Symfony implantation, an extended-range-of-vision intraocular lens, during October 2016-January 2020 at Daqing Oilfield General Hospital, China. Four different predictive models were used to predict good post-operative DoF (⩾2.5 D): Extreme Gradient Boost (XGBoost), random forest (RF), LASSO penalized regression, and multivariable logistic regression (MLR). Apriori algorithm was employed to further explore the association between patient attributes and DoF. RESULTS: A total of 182 unique cases (143 patients) were included. The XGBoost model produced the best predictive accuracy compared to RF, LASSO, and MLR models. Overall performance of the best fitting XGBoost model was as follows: accuracy = 70.3%, AUC = 80.2%, sensitivity = 65.5%, and specificity = 87.5%. The Apriori algorithm identified six preoparative attributes with substantial effects on good post-operative DoF: low anterior chamber depth (ACD) (1.9 to <2.5 mm), smaller pupil size (1.7 to <2.5 mm), low-to-mid axial length (21 to <23 mm), minimum astigmatism degree (-0.2 to 0 diopter), low IOP (9 to <12 mmHg), and medium lens target refractive error (-0.5 to <-0.25 diopter). CONCLUSIONS: Machine Learning models were able to predict good post-operative DoF among cataract patients receiving a Tecnis Symfony ocular lens implantation. The accuracy of the model was above 70%. The Apriori algorithm identified six preoperative attributes with a strong association with post-operative DoF.


Assuntos
Catarata , Lentes Intraoculares , Facoemulsificação , Humanos , Implante de Lente Intraocular , Aprendizado de Máquina , Estudos Prospectivos , Desenho de Prótese , Pseudofacia , Refração Ocular , Estudos Retrospectivos
9.
FASEB J ; 34(8): 10731-10750, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32614098

RESUMO

The corpus luteum is a transient endocrine gland that synthesizes and secretes the steroid hormone, progesterone, which is vital for establishment and maintenance of pregnancy. Luteinizing hormone (LH) via activation of protein kinase A (PKA) acutely stimulates luteal progesterone synthesis via a complex process, converting cholesterol via a series of enzymatic reactions, into progesterone. Lipid droplets in steroidogenic luteal cells store cholesterol in the form of cholesterol esters, which are postulated to provide substrate for steroidogenesis. Early enzymatic studies showed that hormone sensitive lipase (HSL) hydrolyzes luteal cholesterol esters. In this study, we tested whether HSL is a critical mediator of the acute actions of LH on luteal progesterone production. Using LH-responsive bovine small luteal cells our results reveal that LH, forskolin, and 8-Br cAMP-induced PKA-dependent phosphorylation of HSL at Ser563 and Ser660, events known to promote HSL activity. Small molecule inhibition of HSL activity and siRNA-mediated knock down of HSL abrogated LH-induced progesterone production. Moreover, western blotting and confocal microscopy revealed that LH stimulates phosphorylation and translocation of HSL to lipid droplets. Furthermore, LH increased trafficking of cholesterol from the lipid droplets to the mitochondria, which was dependent on both PKA and HSL activation. Taken together, these findings identify a PKA/HSL signaling pathway in luteal cells in response to LH and demonstrate the dynamic relationship between PKA, HSL, and lipid droplets in luteal progesterone synthesis.


Assuntos
Transporte Biológico/fisiologia , Colesterol/metabolismo , Gotículas Lipídicas/metabolismo , Células Lúteas/metabolismo , Mitocôndrias/metabolismo , Animais , Bovinos , Colforsina/metabolismo , Corpo Lúteo/metabolismo , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Feminino , Hormônio Luteinizante/metabolismo , Fosforilação/fisiologia , Gravidez , Progesterona/metabolismo , Transdução de Sinais/fisiologia
10.
Sci Rep ; 10(1): 11287, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32647143

RESUMO

Establishment and maintenance of pregnancy depends on progesterone synthesized by luteal tissue in the ovary. Our objective was to identify the characteristics of lipid droplets (LDs) in ovarian steroidogenic cells. We hypothesized that LDs are a major feature of steroidogenic luteal cells and store cholesteryl esters. Whole bovine tissues, isolated ovarian steroidogenic cells (granulosa, theca, small luteal, and large luteal), and isolated luteal LDs were assessed for LD content, LD-associated proteins and lipid analyses. Bovine luteal tissue contained abundant lipid droplets, LD-associated perilipins 2/3/5, hormone-sensitive lipase, and 1-acylglycerol-3-phosphate O-acyltransferase ABHD5. Luteal tissue was enriched in triglycerides (TGs) compared to other tissues, except for adipose tissue. Luteal cells were distinguishable from follicular cells by the presence of LDs, LD-associated proteins, and increased TGs. Furthermore, LDs from large luteal cells were numerous and small; whereas, LDs from small luteal cells were large and less numerous. Isolated LDs contained nearly all of the TGs and cholesteryl esters present in luteal tissue. Isolated luteal LDs were composed primarily of TG, with lesser amounts of cholesteryl esters, diglyceride and other phospholipids. Bovine luteal LDs are distinct from LDs in other bovine tissues, including follicular steroidogenic cells.


Assuntos
Corpo Lúteo/metabolismo , Gotículas Lipídicas/química , Lipídeos/química , Ovário/metabolismo , 1-Acilglicerol-3-Fosfato O-Aciltransferase/química , Animais , Bovinos , Ésteres do Colesterol/metabolismo , Feminino , Células da Granulosa/metabolismo , Lipidômica , Células Lúteas/metabolismo , Microscopia Confocal , Ovulação , Perilipina-1/química , Progesterona/metabolismo , Espectrometria de Massas em Tandem , Células Tecais/metabolismo
11.
Reprod Biomed Online ; 40(6): 765-767, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32312513

RESUMO

'Androgenized' rodent models are widely used to explore the pathophysiology underlying human polycystic ovary syndrome (PCOS), including reproductive and metabolic dysfunction. Based on a recent study using a dihydrotestosterone (DHT)-treated murine model, it has been proposed that prenatal androgen excess alone can predispose to transgenerational transmission of PCOS. From RNA sequencing analysis of metaphase II (MII) oocytes of androgenized lineages, the authors speculated that oocyte factors, including up-regulation of cytotoxic granulosa-associated RNA binding protein-like 1 (TiaL1), are sufficient to promote disease transfer across generations. Although this is an intriguing concept, it was not considered in the context of earlier publications in which the transcriptomes of human MII oocytes from PCOS women undergoing IVF were compared with women without PCOS. In one of these papers, a number of differentially expressed genes in PCOS MII oocytes (TIAL1 was not differentially expressed) were found to have putative response elements in their promoters for androgen receptors and peroxisome proliferating receptor gamma, providing a mechanism for how excess androgens and/or metabolic defects associated with PCOS might affect female germ cells.


Assuntos
Síndrome do Ovário Policístico , Animais , Feminino , Humanos , Camundongos , Oócitos , Primatas , Proteínas de Ligação a RNA , Receptores Androgênicos/genética , Transcriptoma
12.
Nat Commun ; 11(1): 1621, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32238803

RESUMO

Activin receptor-like kinase 1 (ALK1)-mediated endothelial cell signalling in response to bone morphogenetic protein 9 (BMP9) and BMP10 is of significant importance in cardiovascular disease and cancer. However, detailed molecular mechanisms of ALK1-mediated signalling remain unclear. Here, we report crystal structures of the BMP10:ALK1 complex at 2.3 Å and the prodomain-bound BMP9:ALK1 complex at 3.3 Å. Structural analyses reveal a tripartite recognition mechanism that defines BMP9 and BMP10 specificity for ALK1, and predict that crossveinless 2 is not an inhibitor of BMP9, which is confirmed by experimental evidence. Introduction of BMP10-specific residues into BMP9 yields BMP10-like ligands with diminished signalling activity in C2C12 cells, validating the tripartite mechanism. The loss of osteogenic signalling in C2C12 does not translate into non-osteogenic activity in vivo and BMP10 also induces bone-formation. Collectively, these data provide insight into ALK1-mediated BMP9 and BMP10 signalling, facilitating therapeutic targeting of this important pathway.


Assuntos
Receptores de Activinas Tipo II/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Fator 2 de Diferenciação de Crescimento/metabolismo , Transdução de Sinais/fisiologia , Receptores de Activinas Tipo II/química , Animais , Sítios de Ligação , Proteínas Morfogenéticas Ósseas/química , Osso e Ossos/química , Osso e Ossos/metabolismo , Linhagem Celular , Cristalografia por Raios X , Células Endoteliais/metabolismo , Fator 2 de Diferenciação de Crescimento/química , Humanos , Ligantes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Conformação Proteica , Domínios Proteicos , Fator de Crescimento Transformador beta/metabolismo
13.
FASEB J ; 34(4): 5299-5316, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32077149

RESUMO

The corpus luteum is an endocrine gland that synthesizes and secretes progesterone. Luteinizing hormone (LH) activates protein kinase A (PKA) signaling in luteal cells, increasing delivery of substrate to mitochondria for progesterone production. Mitochondria maintain a highly regulated equilibrium between fusion and fission in order to sustain biological function. Dynamin-related protein 1 (DRP1), is a key mediator of mitochondrial fission. The mechanism by which DRP1 is regulated in the ovary is largely unknown. We hypothesize that LH via PKA differentially regulates the phosphorylation of DRP1 on Ser616 and Ser637 in bovine luteal cells. In primary cultures of steroidogenic small luteal cells (SLCs), LH, and forskolin stimulated phosphorylation of DRP1 (Ser 637), and inhibited phosphorylation of DRP1 (Ser 616). Overexpression of a PKA inhibitor blocked the effects of LH and forskolin on DRP1 phosphorylation. In addition, LH decreased the association of DRP1 with the mitochondria. Genetic knockdown of the DRP1 mitochondria receptor, and a small molecule inhibitor of DRP1 increased basal and LH-induced progesterone production. Studies with a general Dynamin inhibitor and siRNA knockdown of DRP1 showed that DRP1 is required for optimal LH-induced progesterone biosynthesis. Taken together, the findings place DRP1 as an important target downstream of PKA in steroidogenic luteal cells.


Assuntos
Corpo Lúteo/metabolismo , Dinaminas/metabolismo , Hormônio Luteinizante/farmacologia , Dinâmica Mitocondrial , Progesterona/biossíntese , Animais , Bovinos , Corpo Lúteo/efeitos dos fármacos , AMP Cíclico/metabolismo , Dinaminas/genética , Feminino , Fosforilação , Transdução de Sinais
14.
FASEB J ; 34(1): 1728-1744, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31914625

RESUMO

Gestational diabetes mellitus (GDM) is a common pregnancy complication, particularly prevalent in obese women. Importantly, exercise has beneficial impacts on maternal glucose control and may prevent GDM in "at-risk" women. We aimed to determine whether a high-fat diet (HFD) exacerbates metabolic dysfunction and alters gut microbiome in GDM and whether endurance exercise prevents these changes. Uteroplacental insufficiency was induced by bilateral uterine vessel ligation (Restricted) or sham (Control) surgery on E18 in Wistar-Kyoto rats. Female offspring were fed a Chow or HFD (23% fat) from weaning (5 weeks) and at 16 weeks randomly allocated to remain Sedentary or to an exercise protocol of either Exercise prior to and during pregnancy (Exercise); or Exercise during pregnancy only (PregEx). Females were mated (20 weeks) and underwent indirect calorimetry (embryonic day 16; E16), glucose tolerance testing (E18), followed by 24-hr feces collection at E19 (n = 8-10/group). HFD consumption in female rats with GDM exacerbated the adverse metabolic adaptations to pregnancy and altered gut microbial populations. Specifically, the Firmicutes-to-Bacteroidetes ratio was increased, due to an underlying change in abundance of the orders Clostridiales and Bacteroidales. Maternal Exercise, but not PregEx, prevented the development of metabolic dysfunction, increased pancreatic ß-cell mass, and prevented the alteration of the gut microbiome in GDM females. Our findings suggest that maternal exercise and diet influence metabolic and microbiome dysfunction in females with GDM, which may impact long-term maternal and offspring health.


Assuntos
Diabetes Gestacional/metabolismo , Diabetes Gestacional/fisiopatologia , Microbiota/fisiologia , Condicionamento Físico Animal/fisiologia , Animais , Peso Corporal/fisiologia , Dieta Hiperlipídica/efeitos adversos , Feminino , Microbioma Gastrointestinal/fisiologia , Obesidade/metabolismo , Obesidade/fisiopatologia , Gravidez , Ratos , Desmame
15.
Biol Reprod ; 102(3): 680-692, 2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-31723977

RESUMO

Follicular progression during peripuberty is affected by diet. Vascular endothelial growth factor A (VEGFA) induces follicle progression in many species; however, there are limited studies to determine if diet may alter the effects of angiogenic VEGFA165-stimulated follicle progression or antiangiogenic VEGFA165b follicle arrest. We hypothesized that diet affects the magnitude of angiogenic and antiangiogenic VEGFA isoform actions on follicular development through diverse signal transduction pathways. To test this hypothesis, beef heifers in our first trial received Stair-Step (restricted and refeeding) or control diets from 8 to 13 months of age. Ovaries were collected to determine follicle stages, measure vascular gene expression and conduct ovarian cortical cultures. Ovarian cortical cultures were treated with phosphate-buffered saline (control), 50 ng/ml VEGFA165, VEGFA165b, or VEGFA165 + VEGFA165b. The Stair-Step heifers had more primordial follicles (P < 0.0001), greater messenger RNA abundance of vascular markers VE-cadherin (P < 0.0001) and NRP-1 (P < 0.0051) than controls at 13 months of age prior to culture. After culture, VEGFA isoforms had similar effects, independent of diet, where VEGFA165 stimulated and VEGFA165b inhibited VEGFA165-stimulated follicle progression from early primary to antral follicle stages. In vitro cultures were treated with VEGFA isoforms and signal transduction array plates were evaluated. VEGFA165 stimulated expression of genes related to cell cycle, cell proliferation, and growth while VEGFA165b inhibited expression of those genes. Thus, VEGFA isoforms can act independently of diet to alter follicle progression or arrest. Furthermore, follicle progression can be stimulated by VEGFA165 and inhibited by VEGFA165b through diverse signal transduction pathways.


Assuntos
Dieta , Folículo Ovariano/metabolismo , Ovário/metabolismo , Isoformas de Proteínas/metabolismo , Transdução de Sinais/fisiologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Bovinos , Feminino , Neovascularização Fisiológica/fisiologia , Isoformas de Proteínas/genética , Fator A de Crescimento do Endotélio Vascular/genética
16.
Comp Med ; 70(1): 83-86, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31747992

RESUMO

On postmortem examination, 2 geriatric captive male squirrel monkeys (Saimiri sciureus) were found to have pituitary masses that were unassociated with previous experimental manipulation. Both animals were euthanized due to apparently unrelated clinical reasons. Histopathology and immunohistochemical staining classified these tumors as thyrotrophic and corticotrophic pituitary adenomas. These cases represent the first reports of this tumor type in squirrel monkeys.


Assuntos
Adenoma/patologia , Neoplasias Hipofisárias/patologia , Saimiri , Adenoma/veterinária , Animais , Evolução Fatal , Masculino , Doenças dos Macacos/patologia , Neoplasias Hipofisárias/veterinária
17.
Biol Reprod ; 101(5): 1001-1017, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31350850

RESUMO

Yes-associated protein 1 (YAP1) is a major component of the Hippo signaling pathway. Although the exact extracellular signals that control the Hippo pathway are currently unknown, increasing evidence supports a critical role for the Hippo pathway in embryonic development, regulation of organ size, and carcinogenesis. Granulosa cells (GCs) within the ovarian follicle proliferate and produce steroids and growth factors, which facilitate the growth of follicle and maturation of the oocyte. We hypothesize that YAP1 plays a role in proliferation and estrogen secretion of GCs. In the current study, we examined the expression of the Hippo signaling pathway in bovine ovaries and determined whether it was important for GC proliferation and estrogen production. Mammalian STE20-like protein kinase 1 (MST1) and large tumor suppressor kinase 2 (LATS2) were identified as prominent upstream components of the Hippo pathway expressed in granulosa and theca cells of the follicle and large and small cells of the corpus luteum. Immunohistochemistry revealed that YAP1 was localized to the nucleus of growing follicles. In vitro, nuclear localization of the downstream Hippo signaling effector proteins YAP1 and transcriptional co-activator with PDZ-binding motif (TAZ) was inversely correlated with GC density, with greater nuclear localization under conditions of low cell density. Treatment with verteporfin and siRNA targeting YAP1 or TAZ revealed a critical role for these transcriptional co-activators in GC proliferation. Furthermore, knockdown of YAP1 in GCs inhibited follicle-stimulating hormone (FSH)-induced estradiol biosynthesis. The data indicate that Hippo pathway transcription co-activators YAP1/TAZ play an important role in GC proliferation and estradiol synthesis, two processes necessary for maintaining normal follicle development.


Assuntos
Proliferação de Células/fisiologia , Fatores de Transcrição/metabolismo , Animais , Bovinos , Células Cultivadas , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Técnicas de Silenciamento de Genes , Células da Granulosa/metabolismo , Fármacos Fotossensibilizantes/farmacologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Verteporfina/farmacologia
18.
Ann Surg Oncol ; 25(10): 2953-2957, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29971672

RESUMO

BACKGROUND: This study aimed to investigate the changes in diagnosis after a second opinion for breast cancer patients from a multi-disciplinary tumor board (MTB) review at an National Cancer Institute (NCI)-designated cancer center. METHODS: A retrospective study analyzed patients with a breast cancer diagnosed at an outside institution who presented for a second opinion from August 2015 to March 2016 at the Medical University of South Carolina (MUSC). Radiology, pathology, and genetic testing reports from outside institutions were compared with reports generated after an MTB review and subsequent workup at MUSC. The second-opinion cases were categorized based on whether diagnostic variations were present or not. RESULTS: The review included 70 patients seeking second opinions, and 33 (47.1%) of these patients had additional radiologic images. A total of 30 additional biopsies were performed for 25 patients, with new cancers identified in 16 patients. Overall, 16 (22.8%) of the 70 of patients had additional cancers diagnosed. For 14 (20%) of the 70 patients, a second opinion led to a change in pathology interpretation. Genetic testing was performed for 11 patients (15.7%) who met the National Comprehensive Cancer Network (NCCN) guidelines for genetic testing, but none showed a mutation other than a variant of unknown significance. After a complete workup, 30 (42.8%) of the 70 patients had a change in diagnosis as a result of the MTB review. CONCLUSION: A review by an MTB at an NCI-designated cancer center changed the diagnosis for 43% of the patients who presented for a second opinion for breast cancer. The study findings support the conclusion that referral for a second opinion is beneficial and has a diagnostic impact for many patients.


Assuntos
Neoplasias da Mama/patologia , Institutos de Câncer , Carcinoma in Situ/patologia , Erros de Diagnóstico/prevenção & controle , Variações Dependentes do Observador , Encaminhamento e Consulta/estatística & dados numéricos , Biópsia , Feminino , Seguimentos , Testes Genéticos , Humanos , National Cancer Institute (U.S.) , Invasividade Neoplásica , Radiologia , Estudos Retrospectivos , Estados Unidos
19.
Front Microbiol ; 9: 121, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29483898

RESUMO

Understanding how biotic and abiotic factors govern the assembly of rhizosphere-microbial communities is a long-standing goal in microbial ecology. In phytoremediation research, where plants are used to remediate heavy metal-contaminated soils, a deeper understanding of rhizosphere-microbial ecology is needed to fully exploit the potential of microbial-assisted phytoremediation. This study investigated whether Grime's competitor/stress-tolerator/ruderal (CSR) theory could be used to describe the impact of cadmium (Cd) and the presence of a Cd-accumulating plant, Carpobrotus rossii (Haw.) Schwantes, on the assembly of soil-bacterial communities using Illumina 16S rRNA profiling and the predictive metagenomic-profiling program, PICRUSt. Using predictions based on CSR theory, we hypothesized that Cd and the presence of a rhizosphere would affect community assembly. We predicted that the additional resource availability in the rhizosphere would enrich for competitive life strategists, while the presence of Cd would select for stress-tolerators. Traits identified as competitive followed CSR predictions, discriminating between rhizosphere and bulk-soil communities whilst stress-tolerance traits increased with Cd dose, but only in bulk-soil communities. These findings suggest that a bacterium's competitive attributes are critical to its ability to occupy and proliferate in a Cd-contaminated rhizosphere. Ruderal traits, which relate to community re-colonization potential, were synergistically decreased by the presence of the rhizosphere and Cd dose. Taken together this microcosm study suggests that the CSR theory is broadly applicable to microbial communities. Further work toward developing a simplified and robust strategy for microbial CSR classification will provide an ecologically meaningful framework to interpret community-level changes across a range of biomes.

20.
Am J Trop Med Hyg ; 97(2): 548-555, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28829738

RESUMO

Histopathological data collected from patients with severe malaria have been instrumental for studying malaria pathogenesis. Animal models of malaria are critical to complement such studies. Here, the histopathological changes observed in a rhesus macaque with severe and complicated Plasmodium cynomolgi malaria are reported. The animal presented with thrombocytopenia, severe anemia, and hyperparasitemia during the acute infection. The macaque was given subcurative antimalarial treatment, fluid support, and a blood transfusion to treat the clinical complications, but at the time of transfusion, kidney function was compromised. These interventions did not restore kidney function, and the animal was euthanized due to irreversible renal failure. Gross pathological and histological examinations revealed that the lungs, kidneys, liver, spleen, and bone marrow exhibited abnormalities similar to those described in patients with malaria. Overall, this case report illustrates the similarities in the pathophysiological complications that can occur in human malaria and cynomolgi malaria in rhesus macaques.


Assuntos
Macaca mulatta/parasitologia , Malária/complicações , Malária/parasitologia , Plasmodium cynomolgi/isolamento & purificação , Plasmodium cynomolgi/parasitologia , Plasmodium cynomolgi/patogenicidade , Animais , Medula Óssea/anatomia & histologia , Modelos Animais de Doenças , Humanos , Rim/citologia , Fígado/citologia , Pulmão/citologia , Malária/patologia , Baço/citologia
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