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Just like the androgen receptor (AR), the estrogen receptor [alpha] (ER[alpha]) is expressed in the prostate and is thought to influence prostate cancer (PCa) biology. Yet the incomplete understanding of ER[alpha] functions in PCa hinders our ability to fully comprehend its clinical relevance and restricts the repurposing of estrogen- targeted therapies for the treatment of this disease. Using 2 human PCa tissue microarray cohorts, we first demonstrate that nuclear ER[alpha] expression was heterogeneous among patients, being detected in only half of the tumors. Positive nuclear ER[alpha] levels were correlated with disease recurrence, progression to metastatic PCa, and patient survival. Using in vitro and in vivo models of the normal prostate and PCa, bulk and single-cell RNA-Seq analyses revealed that estrogens partially mimicked the androgen transcriptional response and activated specific biological pathways linked to proliferation and metabolism. Bioenergetic flux assays and metabolomics confirmed the regulation of cancer metabolism by estrogens, supporting proliferation. Using cancer cell lines and patient- derived organoids, selective estrogen receptor modulators, a pure anti-estrogen, and genetic approaches impaired cancer cell proliferation and growth in an ER[alpha]-dependent manner. Overall, our study revealed that, when expressed, ER[alpha] functionally reprogrammed PCa metabolism, was associated with disease progression, and could be targeted for therapeutic purposes., Introduction Prostate cancer (PCa) is the most common cancer for men in 112 countries (1). This disease is highly dependent on the androgen receptor (AR), a transcription factor that modulates [...]

Shear stress, resulting from fluid flow, is a fundamental mechanical stimulus affecting various cellular functions. The epididymis, essential for sperm maturation, offers a compelling model to study the effects of shear stress on cellular behavior. This organ undergoes extensive proliferation and differentiation until puberty, achieving full functionality as spermatozoa commence their post‐testicular maturation. Although the mechanical tension exerted by testicular fluid is hypothesized to drive epithelial proliferation and differentiation, the precise mechanisms remain unclear. Here we assessed whether the responsiveness of the epididymal cells to shear stress depends on functional primary cilia by combining microfluidic strategies on immortalized epididymal cells, calcium signaling assays, and high‐throughput gene expression analysis. We identified 97 genes overexpressed in response to shear stress, including early growth response (Egr) 2/3, cellular communication network factor (Ccn) 1/2, and Fos proto‐oncogene (Fos). While shear stress triggered a rapid increase of intracellular Ca2+, this response was abrogated following the impairment of primary ciliogenesis through pharmacological and siRNA approaches. Overall, our findings provide valuable insights into how mechanical forces influence the development of the male reproductive system, a requisite to sperm maturation. [ABSTRACT FROM AUTHOR]

Leydig cells produce hormones required for the development and maintenance of sex characteristics and fertility in males. MEF2 transcription factors are important regulators of Leydig cell gene expression and steroidogenesis. ERK5 is an atypical member of the MAP kinase family that modulates transcription factor activity, either by direct phosphorylation or by acting as a transcriptional coactivator. While MEF2 and ERK5 are known to cooperate transcriptionally, the presence and role of ERK5 in Leydig cells remained unknown. Our goal was to determine whether ERK5 is present in Leydig cells and whether it cooperates with MEF2 to regulate gene expression. We found that ERK5 is present in Leydig cells in testicular tissue and immortalized cell lines. ERK5 knockdown in human chorionic gonadotrophin–treated MA-10 Leydig cells reduced steroidogenesis and decreased Star and Nr4a1 expression. Luciferase assays using a synthetic reporter plasmid containing 3 MEF2 elements revealed that ERK5 enhances MEF2-dependent promoter activation. Although ERK5 did not cooperate with MEF2 on the Star promoter in Leydig cell lines, we found that ERK5 and MEF2C do cooperate on the Nr4a1 promoter, which contains 2 adjacent MEF2 elements. Mutation of each MEF2 element in a short version of the Nr4a1 promoter significantly decreased the ERK5/MEF2C cooperation, indicating that both MEF2 elements need to be intact. The ERK5/MEF2C cooperation did not require phosphorylation of MEF2C on Ser387. Taken together, our data identify ERK5 as a new regulator of MEF2 activity in Leydig cells and provide potential new insights into mechanisms that regulate Leydig cell gene expression and function. [ABSTRACT FROM AUTHOR]

Kupffer cells are the primary liver resident immune cell responsible for the liver firewall function, including clearance of bacterial infection from the circulation, as they are strategically positioned inside the liver sinusoid with intimate contact with the blood. Disruption in the tissue-resident macrophage niche, such as in Kupffer cells, can lead to a window of susceptibility to systemic infections, which represents a significant cause of mortality in patients with acetaminophen (APAP) overdose-induced acute liver injury (ALI). However, how Kupffer cell niche disruption increases susceptibility to systemic infections in ALI is not fully understood. Using a mouse model of ALI induced by APAP overdose, we found that Kupffer cells upregulated the apoptotic cell death program and were markedly reduced in the necrotic areas during the early stages of ALI, opening the niche for the infiltration of neutrophils and monocyte subsets. In addition, during the resolution phase of ALI, the remaining tissue macrophages with a Kupffer cell morphology were observed forming replicating cell clusters closer to necrotic areas devoid of Kupffer cells. Interestingly, mice with APAP-induced liver injury were still susceptible to infections despite the dual cellular input of circulating monocytes and proliferation of remaining Kupffer cells in the damaged liver. Therapy with bone marrow-derived macrophages (BMDM) was shown to be effective in occupying the niche devoid of Kupffer cells following APAP-induced ALI. The rapid BMDM migration to the liver and their positioning within necrotic areas enhanced the healing of the tissue and restored the liver firewall function after BMDM therapy. Therefore, we showed that disruption in the Kupffer cell niche and its impaired function during acute liver injury are key factors for the susceptibility to systemic bacterial infections. In addition, modulation of the liver macrophage niche was shown to be a promising therapeutic strategy for liver injuries that reduce the Kupffer cell number and compromise the organ function. [ABSTRACT FROM AUTHOR]

The emergence of life-threatening zoonotic diseases caused by betacoronaviruses, including the ongoing coronavirus disease 19 (COVID-19) pandemic, has highlighted the need for developing preclinical models mirroring respiratory and systemic pathophysiological manifestations seen in infected humans. Here, we showed that C57BL/6J wild-type mice intranasally inoculated with the murine betacoronavirus murine hepatitis coronavirus 3 (MHV-3) develop a robust inflammatory response leading to acute lung injuries, including alveolar edema, hemorrhage, and fibrin thrombi. Although such histopathological changes seemed to resolve as the infection advanced, they efficiently impaired respiratory function, as the infected mice displayed restricted lung distention and increased respiratory frequency and ventilation. Following respiratory manifestation, the MHV-3 infection became systemic, and a high virus burden could be detected in multiple organs along with morphological changes. The systemic manifestation of MHV-3 infection was also marked by a sharp drop in the number of circulating platelets and lymphocytes, besides the augmented concentration of the proinflammatory cytokines interleukin 1 beta (IL-1β), IL-6, IL-12, gamma interferon (IFN-γ), and tumor necrosis factor (TNF), thereby mirroring some clinical features observed in moderate and severe cases of COVID-19. Importantly, both respiratory and systemic changes triggered by MHV-3 infection were greatly prevented by blocking TNF signaling, either via genetic or pharmacologic approaches. In line with this, TNF blockage also diminished the infection-mediated release of proinflammatory cytokines and virus replication of human epithelial lung cells infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Collectively, results show that MHV-3 respiratory infection leads to a large range of clinical manifestations in mice and may constitute an attractive, lower-cost, biosafety level 2 (BSL2) in vivo platform for evaluating the respiratory and multiorgan involvement of betacoronavirus infections. [ABSTRACT FROM AUTHOR]

Background: Triatomines (Hemiptera, Reduviidae) are vectors of Trypanosoma cruzi, the causative agent of Chagas disease, one of the most important vector-borne diseases in Latin America. This study compares the environmental niche spaces of Triatoma brasiliensis and Triatoma melanica using ecological niche modelling and reports findings on DNA barcoding and wing geometric morphometrics as tools for the identification of these species. Methods: We compared the geographic distribution of the species using generalized linear models fitted to elevation and current data on land surface temperature, vegetation cover and rainfall recorded by earth observation satellites for northeastern Brazil. Additionally, we evaluated nucleotide sequence data from the barcode region of the mitochondrial cytochrome c oxidase subunit I (CO1) and wing geometric morphometrics as taxonomic identification tools for T. brasiliensis and T. melanica. Results: The ecological niche models show that the environmental spaces currently occupied by T. brasiliensis and T. melanica are similar although not equivalent, and associated with the caatinga ecosystem. The CO1 sequence analyses based on pair wise genetic distance matrix calculated using Kimura 2-Parameter (K2P) evolutionary model, clearly separate the two species, supporting the barcoding gap. Wing size and shape analyses based on seven landmarks of 72 field specimens confirmed consistent differences between T. brasiliensis and T. melanica. Conclusion: Our results suggest that the separation of the two species should be attributed to a factor that does not include the current environmental conditions. However, as the caatinga is a biome that has existed in the area for at least the last 18,000 years, past conditions might have had an influence in the speciation process. The DNA Barcoding approach may be extended to these members of the subfamily Triatominae. [ABSTRACT FROM AUTHOR]

Background: Triatomines (Hemiptera, Reduviidae) are vectors of Trypanosoma cruzi, the causative agent of Chagas disease, one of the most important vector-borne diseases in Latin America. This study compares the environmental niche spaces of Triatoma brasiliensis and Triatoma melanica using ecological niche modelling and reports findings on DNA barcoding and wing geometric morphometrics as tools for the identification of these species. Methods: We compared the geographic distribution of the species using generalized linear models fitted to elevation and current data on land surface temperature, vegetation cover and rainfall recorded by earth observation satellites for northeastern Brazil. Additionally, we evaluated nucleotide sequence data from the barcode region of the mitochondrial cytochrome c oxidase subunit I (CO1) and wing geometric morphometrics as taxonomic identification tools for T. brasiliensis and T. melanica. Results: The ecological niche models show that the environmental spaces currently occupied by T. brasiliensis and T. melanica are similar although not equivalent, and associated with the caatinga ecosystem. The CO1 sequence analyses based on pair wise genetic distance matrix calculated using Kimura 2-Parameter (K2P) evolutionary model, clearly separate the two species, supporting the barcoding gap. Wing size and shape analyses based on seven landmarks of 72 field specimens confirmed consistent differences between T. brasiliensis and T. melanica. Conclusion: Our results suggest that the separation of the two species should be attributed to a factor that does not include the current environmental conditions. However, as the caatinga is a biome that has existed in the area for at least the last 18,000 years, past conditions might have had an influence in the speciation process. The DNA Barcoding approach may be extended to these members of the subfamily Triatominae. [ABSTRACT FROM AUTHOR]

Introduction: Tissue injury results in the release of inflammatory mediators, including a cascade of algogenic substances, which contribute to the development of hyperalgesia. During this process, endogenous analgesic substances are peripherally released to counterbalance hyperalgesia. The present study aimed to investigate whether inflammatory mediators TNF-α, IL-1β, CXCL1, norepinephrine (NE), and prostaglandin E2 (PGE2) may be involved in the deflagration of peripheral endogenous modulation of inflammatory pain by activation of the cholinergic system. Methods: Male Swiss mice were subjected to paw withdrawal test. All the substances were injected via the intraplantar route. Results: The main findings of this study were as follows: (1) carrageenan (Cg), TNF-α, CXCL-1, IL1-β, NE, and PGE2 induced hyperalgesia; (2) the acetylcholinesterase enzyme inhibitor, neostigmine, reversed the hyperalgesia observed after Cg, TNF-α, CXCL-1, and IL1-β injection; (3) the non-selective muscarinic receptor antagonist, atropine, and the selective muscarinic type 1 receptor (m1AChr) antagonist, telenzepine, potentiated the hyperalgesia induced by Cg and CXCL-1; (4) mecamylamine, a non-selective nicotinic receptor antagonist, potentiated the hyperalgesia induced by Cg, TNF-α, CXCL-1, and IL1-β; (5) Cg, CXCL-1, and PGE2 increased the expression of the m1AChr and nicotinic receptor subunit α4protein. Conclusion: These results suggest that the cholinergic system may modulate the inflammatory pain induced by Cg, PGE2, TNF-α, CXCL-1, and IL1-β. [ABSTRACT FROM AUTHOR]

Tissue injury results in the release of inflammatory mediators, including a cascade of nociceptive substances, which contribute to development of hyperalgesia. In addition, during this process endogenous analgesic substances are also peripherally released with the aim of controlling the hyperalgesia. Thus, the present study aimed to investigate whether inflammatory mediators TNF-α, IL-1β, CXCL1, norepinephrine (NE) and prostaglandin E2 (PGE2) may be involved in the deflagration of peripheral endogenous modulation of inflammatory pain by activation of the opioid system. Thus, male Swiss mice and the paw withdrawal test were used. All substances were injected by the intraplantar route. Carrageenan, TNF-α, CXCL-1, IL1-β, NE and PGE2 induced hyperalgesia. Selectives μ (clocinamox), δ (naltrindole) and κ (norbinaltorphimine, nor-BNI) and non-selective (naloxone) opioid receptor antagonists potentiated the hyperalgesia induced by carrageenan, TNF-α, CXCL-1 and IL1-β. In contrast, when the enzyme N-aminopeptidase involved in the degradation of endogenous opioid peptides was inhibited by bestatin, the hyperalgesia was significantly reduced. In addition, the western blotting assay indicated that the expression of the opioid δ receptor was increased after intraplantar injection of carrageenan. The data obtained in this work corroborate the hypothesis that TNF-α, CXCL-1 and IL-β cause, in addition to hyperalgesia, the release of endogenous substances such as opioid peptides, which in turn exert endogenous control over peripheral inflammatory pain. [ABSTRACT FROM AUTHOR]