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1.
Development ; 149(3)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35037942

RESUMO

Generating comprehensive image maps, while preserving spatial three-dimensional (3D) context, is essential in order to locate and assess quantitatively specific cellular features and cell-cell interactions during organ development. Despite recent advances in 3D imaging approaches, our current knowledge of the spatial organization of distinct cell types in the embryonic pancreatic tissue is still largely based on two-dimensional histological sections. Here, we present a light-sheet fluorescence microscopy approach to image the pancreas in three dimensions and map tissue interactions at key time points in the mouse embryo. We demonstrate the utility of the approach by providing volumetric data, 3D distribution of three main cellular components (epithelial, mesenchymal and endothelial cells) within the developing pancreas, and quantification of their relative cellular abundance within the tissue. Interestingly, our 3D images show that endocrine cells are constantly and increasingly in contact with endothelial cells forming small vessels, whereas the interactions with mesenchymal cells decrease over time. These findings suggest distinct cell-cell interaction requirements for early endocrine cell specification and late differentiation. Lastly, we combine our image data in an open-source online repository (referred to as the Pancreas Embryonic Cell Atlas).


Assuntos
Imageamento Tridimensional/métodos , Pâncreas/anatomia & histologia , Animais , Embrião de Mamíferos/anatomia & histologia , Desenvolvimento Embrionário , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Epitélio/anatomia & histologia , Proteína Homeobox Nkx-2.5/deficiência , Proteína Homeobox Nkx-2.5/genética , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia de Fluorescência
2.
Psychol Med ; 53(10): 4487-4498, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-35634966

RESUMO

BACKGROUND: The transition to adolescence implicates heightened vulnerability alongside increased opportunities for resilience. Contexts of early life stress (ELS) exacerbate risk; still, little research addressed biobehavioral mediators of risk and resilience across the adolescent transition following ELS. Utilizing a unique cohort, we tested biosocial moderators of chronicity in adolescents' internalizing disorders v. resilience. METHOD: Families exposed to chronic war-related trauma, v. controls, were followed. We utilized data from three time-points framing the adolescent transition: late childhood (N = 177, Mage = 9.3 years ± 1.41), early adolescence (N = 111, Mage = 11 0.66 years ± 1.23), and late adolescence (N = 138, Mage = 15.65 years ± 1.31). In late childhood and late adolescence children's internalizing disorders were diagnosed. At early adolescence maternal and child's hair cortisol concentrations (HCC), maternal sensitivity, and mothers' post-traumatic symptoms evaluated. RESULTS: War-exposed children exhibited more internalizing disorders of chronic trajectory and mothers were less sensitive and more symptomatic. Three pathways elucidated the continuity of psychopathology: (a) maternal sensitivity moderated the risk of chronic psychopathology, (b) maternal post-traumatic symptoms mediated continuity of risk, (c) trauma exposure moderated the association between child internalizing disorders at late childhood and maternal HCC, which linked with child HCC. Child HCC linked with maternal post-traumatic symptoms, which were associated with child disorders in late adolescence. CONCLUSION: Results demonstrate the complex interplay of maternal and child's biosocial factors as mediators and moderators of risk chronicity across the adolescent transition following trauma. Findings are first to utilize maternal and child's HCC as biomarkers of chronic stress v. resilience during adolescence, a period of neural reorganization and personal growth that shapes the individual's lifetime adaptation.


Assuntos
Transtornos de Estresse Pós-Traumáticos , Feminino , Criança , Humanos , Adolescente , Idoso de 80 Anos ou mais , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Hidrocortisona , Mães , Psicopatologia , Relações Mãe-Filho , Cabelo
3.
Environ Res ; 204(Pt D): 112378, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34780787

RESUMO

BACKGROUND AND AIM: Studies have shown that increased maternal cortisol level is associated with child adverse health outcomes. Hair cortisol (HC) is suitable for assessing long-term circulating cortisol concentration. Only two previous studies reported beneficial associations between cortisol and residential greenness during pregnancy and no study focused on the first trimester. Our aim was to evaluate the association between residential greenness and first trimester HC levels among pregnant women in Israel. METHODS: Women were recruited during second and third trimesters. Hair samples were collected from the scalp and retrospective HC levels during the first trimester were quantified for 217 women. HC levels were natural log transformed and outliers were excluded. Based on geocoded birth address, small area sociodemographic status (SES) and mean residential surrounding greenness were calculated using high-resolution satellite-based Normalised Difference Vegetation Index (NDVI) data at 100, 300 and 500-m buffers in a cross-sectional approach. In addition, longitudinal exposure to mean greenness during a week preconception and during the first trimester were calculated. Missing covariates were imputed and linearity of the associations were evaluated. Generalized linear models were used to estimate the crude and adjusted associations controlled for the relevant covariates. RESULTS: After exclusion of outliers, for 211 women, crude and adjusted beneficial associations between exposure to higher mean NDVI and HC levels were observed for all the exposure measures. An increase in 1 interquartile range of greenness (100 m buffer) was associated with a statistically significant lower estimated natural log mean HC level (-0.27 95% CI: -0.44; -0.11). The associations were robust to adjustment for covariates. The findings were consistent for different buffers, for the longitudinal approach, when all observations were included in the analysis and slightly stronger associations were observed for women with addresses geocoded at the home or street level. For most of the exposure measures, stronger associations were observed among those of lower sociodemographic status. CONCLUSION: Our findings that more greenness associated with reduced maternal cortisol levels measured in the hair during the first trimester, could have substantial implications for urban planners and public health professional. If our observations will be replicated, it may present a useful avenue for public-health intervention to promote health through the provision of greenness exposure during early pregnancy, specifically to disadvantage populations.


Assuntos
Meio Ambiente , Cabelo , Hidrocortisona , Primeiro Trimestre da Gravidez , Ambiente Construído/psicologia , Criança , Feminino , Cabelo/química , Promoção da Saúde , Humanos , Hidrocortisona/análise , Israel , Gravidez , Primeiro Trimestre da Gravidez/fisiologia , Primeiro Trimestre da Gravidez/psicologia , Estudos Retrospectivos
4.
J Clin Invest ; 134(14)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38885342

RESUMO

While inflammation is beneficial for insulin secretion during homeostasis, its transformation adversely affects ß cells and contributes to diabetes. However, the regulation of islet inflammation for maintaining glucose homeostasis remains largely unknown. Here, we identified pericytes as pivotal regulators of islet immune and ß cell function in health. Islets and pancreatic pericytes express various cytokines in healthy humans and mice. To interfere with the pericytic inflammatory response, we selectively inhibited the TLR/MyD88 pathway in these cells in transgenic mice. The loss of MyD88 impaired pericytic cytokine production. Furthermore, MyD88-deficient mice exhibited skewed islet inflammation with fewer cells, an impaired macrophage phenotype, and reduced IL-1ß production. This aberrant pericyte-orchestrated islet inflammation was associated with ß cell dedifferentiation and impaired glucose response. Additionally, we found that Cxcl1, a pericytic MyD88-dependent cytokine, promoted immune IL-1ß production. Treatment with either Cxcl1 or IL-1ß restored the mature ß cell phenotype and glucose response in transgenic mice, suggesting a potential mechanism through which pericytes and immune cells regulate glucose homeostasis. Our study revealed pericyte-orchestrated islet inflammation as a crucial element in glucose regulation, implicating this process as a potential therapeutic target for diabetes.


Assuntos
Inflamação , Interleucina-1beta , Fator 88 de Diferenciação Mieloide , Pericitos , Transdução de Sinais , Animais , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Camundongos , Pericitos/metabolismo , Pericitos/patologia , Pericitos/imunologia , Humanos , Inflamação/patologia , Inflamação/metabolismo , Inflamação/genética , Inflamação/imunologia , Interleucina-1beta/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Camundongos Transgênicos , Receptores Toll-Like/metabolismo , Receptores Toll-Like/genética , Quimiocina CXCL1/metabolismo , Quimiocina CXCL1/genética , Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Camundongos Knockout , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Células Secretoras de Insulina/imunologia , Masculino , Glucose/metabolismo
5.
Front Endocrinol (Lausanne) ; 14: 1142988, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36967785

RESUMO

Introduction: Immune cells were recently shown to support ß-cells and insulin secretion. However, little is known about how islet immune cells are regulated to maintain glucose homeostasis. Administration of various cytokines, including Interleukin-33 (IL-33), was shown to influence ß-cell function. However, the role of endogenous, locally produced IL-33 in pancreatic function remains unknown. Here, we show that IL-33, produced by pancreatic pericytes, is required for glucose homeostasis. Methods: To characterize pancreatic IL-33 production, we employed gene expression, flow cytometry, and immunofluorescence analyses. To define the role of this cytokine, we employed transgenic mouse systems to delete the Il33 gene selectively in pancreatic pericytes, in combination with the administration of recombinant IL-33. Glucose response was measured in vivo and in vitro, and morphometric and molecular analyses were used to measure ß-cell mass and gene expression. Immune cells were analyzed by flow cytometry. Resuts: Our results show that pericytes are the primary source of IL-33 in the pancreas. Mice lacking pericytic IL-33 were glucose intolerant due to impaired insulin secretion. Selective loss of pericytic IL-33 was further associated with reduced T and dendritic cell numbers in the islets and lower retinoic acid production by islet macrophages. Discussion: Our study demonstrates the importance of local, pericytic IL-33 production for glucose regulation. Additionally, it proposes that pericytes regulate islet immune cells to support ß-cell function in an IL-33-dependent manner. Our study reveals an intricate cellular network within the islet niche.


Assuntos
Interleucina-33 , Pericitos , Camundongos , Animais , Secreção de Insulina , Interleucina-33/metabolismo , Pericitos/metabolismo , Insulina/metabolismo , Expressão Gênica , Camundongos Transgênicos , Glucose/metabolismo
6.
Conserv Physiol ; 9(1): coab068, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34512990

RESUMO

The predation-stress hypothesis has been proposed as a general mechanism to explain the negative effect of predation risk on reproduction, through a chronic activation of the stress response. However, in some cases, stress appears to augment the reproductive potential of mammals. Wild boar (Sus scrofa) populations are on a rise worldwide, despite the high hunting pressure that they are exposed to. This hunting pressure instigates, among other effects, earlier sexual maturity in juvenile females, leading to the shortening of wild boars' generation time. The mechanism that underlies this earlier sexual maturity under high hunting pressure has not been examined to date. To explore the physiological effects that hunting has on the reproductive system and whether the stress response is involved, we examined steroid hormone levels in the hair of female wild boars in northern Israel, comparing populations exposed to high and low hunting pressure. Furthermore, we compared steroid levels in the hair of female wild boars that were roaming alone or as a part of a group. We found no hormonal signs of stress in the hunted boars. Cortisol levels were low in both the high and low hunting-pressure groups. Yet, progesterone levels were higher in females that were exposed to high hunting pressure. Females roaming in a group also had higher progesterone levels compared to females that were alone, with no distinguishable differences in cortisol levels. These elevations in reproductive hormones that were associated with hunting may lead to a higher reproductive potential in female wild boars. They further show that high hunting pressure does not necessarily lead to chronic stress that impairs the reproductive potential of female wild boars. This data suggests that a reproductive hormonal response may be one of the factors leading to the rapid wild boars population growth worldwide, despite the high hunting pressure.

7.
Dev Cell ; 56(19): 2703-2711.e5, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34499867

RESUMO

Glucose homeostasis depends on regulated insulin secretion from pancreatic ß cells, which acquire their mature phenotype postnatally. The functional maturation of ß cells is regulated by a combination of cell-autonomous and exogenous factors; the identity of the latter is mostly unknown. Here, we identify BMP4 as a critical component through which the pancreatic microenvironment regulates ß cell function. By combining transgenic mouse models and human iPSCs, we show that BMP4 promotes the expression of core ß cell genes and is required for proper insulin production and secretion. We identified pericytes as the primary pancreatic source of BMP4, which start producing this ligand midway through the postnatal period, at the age ß cells mature. Overall, our findings show that the islet niche directly promotes ß cell functional maturation through the timely production of BMP4. Our study highlights the need to recapitulate the physiological postnatal islet niche for generating fully functional stem-cell-derived ß cells for cell replacement therapy for diabetes.


Assuntos
Proteína Morfogenética Óssea 4/metabolismo , Células Secretoras de Insulina/metabolismo , Pâncreas/metabolismo , Animais , Animais Recém-Nascidos , Proteína Morfogenética Óssea 4/fisiologia , Diferenciação Celular/genética , Expressão Gênica/genética , Regulação da Expressão Gênica/genética , Glucose/metabolismo , Proteínas de Homeodomínio/metabolismo , Homeostase , Humanos , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Organogênese , Pâncreas/fisiologia , Pericitos/metabolismo , Transativadores/metabolismo
8.
Reprod Biol ; 18(4): 410-415, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30219333

RESUMO

Maintaining pregnancy to term is important as preterm delivery is a risk factor for impaired infant development, which may have negative long-term consequences. Therefore, developing biomarkers that can predict pregnancy longevity during early gestation is essential for the prevention of preterm birth. Here we explored whether maternal hair testosterone and cortisol, representing the pre-conception and first trimester periods respectively, may be used to predict pregnancy longevity. We recruited 125 pregnant women that contributed hair samples and answered a personal information questionnaire that included pre-conception smoking. We quantified steroids using commercial enzyme-linked immunosorbent assay kits. Gestational age at delivery was obtained from medical records. We used General Linear Models to predict gestation length. The model that included first trimester cortisol, pre-conception smoking, pre-conception testosterone and the interaction between first trimester cortisol and pre-conception smoking predicted 13% of the variance in gestation length (R2 = 0.130; n = 105; p = 0.007). First trimester cortisol was the best predictor of gestational length. Women with high levels of cortisol in their first trimester had an increased probability of a full-term delivery. The effect of cortisol was especially pronounced in smokers (ß = 1.69), compared to non-smokers (ß = 0.45). Pre-conception testosterone also contributed to the model. Our study suggests that hair steroids may be used to predict pregnancy longevity, together with other contributing factors.


Assuntos
Cabelo/química , Hidrocortisona/análise , Testosterona/análise , Adulto , Feminino , Idade Gestacional , Humanos , Gravidez , Terceiro Trimestre da Gravidez , Fatores de Tempo , Adulto Jovem
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