| 1. |
- Aguilar-Pimentel, Juan Antonio, et al.
(författare)
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Increased estrogen to androgen ratio enhances immunoglobulin levels and impairs B cell function in male mice.
- 2020
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Ingår i: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- Sex steroids, such as estrogens and androgens, are important regulators of the humoral immune response. Studies in female mice have demonstrated that alteration of circulating estrogen concentration regulates antibody-mediated immunity. As males have normally little endogenous estrogen, we hypothesized that in males high estrogens and low androgens affect the immune system and enhance the allergic inflammatory response. Here, we studied transgenic male mice expressing human aromatase (AROM+). These animals have a high circulating estrogen to androgen ratio (E/A), causing female traits such as gynecomastia. We found that AROM+ male mice had significantly higher plasma immunoglobulin levels, particularly IgE. Flow cytometry analyses of splenocytes revealed changes in mature/immature B cell ratio together with a transcriptional upregulation of the Igh locus. Furthermore, higher proliferation rate and increased IgE synthesis after IgE class-switching was found. Subsequently, we utilized an ovalbumin airway challenge model to test the allergic response in AROM+ male mice. In line with above observations, an increase in IgE levels was measured, albeit no impact on immune cell infiltration into the lungs was detected. Together, our findings suggest that high circulating E/A in males significantly alters B cell function without any significant enhancement in allergic inflammation.
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| 2. |
- Björkgren, Ida, et al.
(författare)
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Imbalanced lipid homeostasis in the conditional Dicer1 knockout mouse epididymis causes instability of the sperm membrane.
- 2015
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Ingår i: FASEB journal : official publication of the Federation of American Societies for Experimental Biology. - : Wiley. - 1530-6860. ; 29:2, s. 433-442
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Tidskriftsartikel (refereegranskat)abstract
- During epididymal sperm maturation, the lipid content of the sperm membrane is modified, which facilitates sperm motility and fertility. However, little is known about the mechanisms regulating the maturation process. By generating a conditional knockout (cKO) of Dicer1 in the proximal part of the mouse epididymis, we studied the role of RNA interference in epididymal functions. The Dicer1 cKO epididymis displayed an altered lipid homeostasis associated with a 0.6-fold reduction in the expression of the gene elongation of very long chain fatty acids-like 2, an enzyme needed for production of long-chain polyunsaturated fatty acids (PUFAs). Furthermore, the expression of several factors involved in cholesterol synthesis was up-regulated. Accordingly, the Dicer1 cKO sperm membrane showed a 0.7-fold decrease in long-chain PUFAs, whereas the amount of cholesterol in acrosome-reacted sperm displayed a 1.7-fold increase. The increased cholesterol:PUFA ratio of the sperm membrane caused breakage of the neck and acrosome region and immotility of sperm. Dicer1 cKO mice sperm also displayed reduced ability to bind to and fertilize the oocyte in vitro. This study thus shows that Dicer1 is critical for lipid synthesis in the epididymis, which directly affects sperm membrane integrity and male fertility.-Björkgren, I., Gylling, H., Turunen, H., Huhtaniemi, I., Strauss, L., Poutanen, M., Sipilä, P. Imbalanced lipid homeostasis in the conditional Dicer1 knockout mouse epididymis causes instability of the sperm membrane.
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| 3. |
- Damdimopoulou, Pauliina, et al.
(författare)
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A single dose of enterolactone activates estrogen signaling and regulates expression of circadian clock genes in mice.
- 2011
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Ingår i: The Journal of nutrition. - : Elsevier BV. - 1541-6100 .- 0022-3166. ; 141:9, s. 1583-9
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Tidskriftsartikel (refereegranskat)abstract
- Enterolactone (EL) is an enterolignan produced by gut microbiota from dietary plant lignans. Epidemiological and experimental studies suggest that EL and plant lignans may reduce the risk of breast and prostate cancer as well as cardiovascular disease. These effects are thought to at least in part involve modulation of estrogen receptor activity. Surprisingly little is known about the in vivo estrogenicity of EL. In the present study, we investigated the target tissues of EL, the genes affected by EL treatment, and the response kinetics. Following a single dose of EL, luciferase was significantly induced in reproductive and nonreproductive tissues of male and female 3xERE-luciferase mice, indicating estrogen-like activity. Microarray analysis revealed that EL regulated the expression of only 1% of 17β-estradiol target genes in the uterus. The majority of these genes were traditional estrogen target genes, but also members of the circadian signaling pathway were affected. Kinetic analyses showed that EL undergoes rapid phase II metabolism and is efficiently excreted. In vivo imaging demonstrated that the estrogen response followed similar, fast kinetics. We conclude that EL activates estrogen signaling in both male and female mice and that the transient responses may be due to the fast metabolism of the compound. Lastly, EL may represent a link among diet, gut microbiota, and circadian signaling.
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| 4. |
- Kemiläinen, Heidi, et al.
(författare)
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The Hydroxysteroid (17β) Dehydrogenase Family Gene HSD17B12 Is Involved in the Prostaglandin Synthesis Pathway, the Ovarian Function, and Regulation of Fertility.
- 2016
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Ingår i: Endocrinology. - : The Endocrine Society. - 1945-7170 .- 0013-7227. ; 157:10, s. 3719-3730
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Tidskriftsartikel (refereegranskat)abstract
- The hydroxysteroid (17beta) dehydrogenase (HSD17B)12 gene belongs to the hydroxysteroid (17β) dehydrogenase superfamily, and it has been implicated in the conversion of estrone to estradiol as well as in the synthesis of arachidonic acid (AA). AA is a precursor of prostaglandins, which are involved in the regulation of female reproduction, prompting us to study the role of HSD17B12 enzyme in the ovarian function. We found a broad expression of HSD17B12 enzyme in both human and mouse ovaries. The enzyme was localized in the theca interna, corpus luteum, granulosa cells, oocytes, and surface epithelium. Interestingly, haploinsufficiency of the HSD17B12 gene in female mice resulted in subfertility, indicating an important role for HSD17B12 enzyme in the ovarian function. In line with significantly increased length of the diestrous phase, the HSD17B(+/-) females gave birth less frequently than wild-type females, and the litter size of HSD17B12(+/-) females was significantly reduced. Interestingly, we observed meiotic spindle formation in immature follicles, suggesting defective meiotic arrest in HSD17B12(+/-) ovaries. The finding was further supported by transcriptome analysis showing differential expression of several genes related to the meiosis. In addition, polyovular follicles and oocytes trapped inside the corpus luteum were observed, indicating a failure in the oogenesis and ovulation, respectively. Intraovarian concentrations of steroid hormones were normal in HSD17B12(+/-) females, whereas the levels of AA and its metabolites (6-keto prostaglandin F1alpha, prostaglandin D2, prostaglandin E2, prostaglandin F2α, and thromboxane B2) were decreased. In conclusion, our study demonstrates that HSD17B12 enzyme plays an important role in female fertility through its role in AA metabolism.
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| 5. |
- Lahiri, Shibojyoti, et al.
(författare)
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MALDI-IMS combined with shotgun proteomics identify and localize new factors in male infertility.
- 2021
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Ingår i: Life science alliance. - 2575-1077. ; 4:3
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Tidskriftsartikel (refereegranskat)abstract
- Spermatogenesis is a complex multi-step process involving intricate interactions between different cell types in the male testis. Disruption of these interactions results in infertility. Combination of shotgun tissue proteomics with MALDI imaging mass spectrometry is markedly potent in revealing topological maps of molecular processes within tissues. Here, we use a combinatorial approach on a characterized mouse model of hormone induced male infertility to uncover misregulated pathways. Comparative testicular proteome of wild-type and mice overexpressing human P450 aromatase (AROM+) with pathologically increased estrogen levels unravels gross dysregulation of spermatogenesis and emergence of pro-inflammatory pathways in AROM+ testis. In situ MS allowed us to localize misregulated proteins/peptides to defined regions within the testis. Results suggest that infertility is associated with substantial loss of proteomic heterogeneity, which define distinct stages of seminiferous tubuli in healthy animals. Importantly, considerable loss of mitochondrial factors, proteins associated with late stages of spermatogenesis and steroidogenic factors characterize AROM+ mice. Thus, the novel proteomic approach pinpoints in unprecedented ways the disruption of normal processes in testis and provides a signature for male infertility.
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| 6. |
- Strauss, Leena, et al.
(författare)
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Consistent and effective method to define the mouse estrous cycle stage by deep learning based model.
- 2024
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Ingår i: Journal of Endocrinology. - 0022-0795 .- 1479-6805. ; 261:3
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Tidskriftsartikel (refereegranskat)abstract
- The mouse estrous cycle is divided into four stages: proestrus (P), estrus (E), metestrus (M) and diestrus (D). The estrous cycle affects reproductive hormone levels in a wide variety of tissues. Therefore, to obtain reliable results from female mice, it is important to know the estrous cycle stage during sampling. The stage can be analyzed from a vaginal smear under a microscope. However, it is time-consuming, and the results vary between evaluators. Here, we present an accurate and reproducible method for staging the mouse estrous cycle in digital whole slide images (WSIs) of vaginal smears. We developed a model using a deep convolutional neural network (CNN) in a cloud-based platform, Aiforia Create. The CNN was trained by supervised pixel-level multiclass semantic segmentation of image features from 171 hematoxylin-stained samples. The model was validated by comparing the results obtained by CNN with those of four independent researchers. The validation data included three separate studies comprising altogether 148 slides. The total agreement attested by the Fleiss kappa value between the validators and the CNN was excellent (0.75), and when D, E and P were analyzed separately, the kappa values were 0.89, 0.79 and 0.74, respectively. The M stage is short and not well defined by the researchers. Thus, identification of the M stage by the CNN was challenging due to the lack of proper ground truth, and the kappa value was 0.26. We conclude that our model is reliable and effective for classifying the estrous cycle stages in female mice.
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| 7. |
- Strauss, Leena, et al.
(författare)
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Seminal vesicles and urinary bladder as sites of aromatization of androgens in men, evidenced by a CYP19A1-driven luciferase reporter mouse and human tissue specimens.
- 2013
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Ingår i: The FASEB Journal. - : Wiley. - 0892-6638 .- 1530-6860. ; 27:4, s. 1342-50
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Tidskriftsartikel (refereegranskat)abstract
- The human CYP19A1 gene is expressed in various tissues by the use of tissue-specific promoters, whereas the rodent cyp19a1 gene is expressed mainly in the gonads and brain. We generated a transgenic mouse model containing a >100-kb 5' region of human CYP19A1 gene connected to a luciferase reporter gene. The luciferase activity in mouse tissues mimicked the CYP19A1 gene expression pattern in humans. Interestingly, the reporter gene activity was 16 and 160 times higher in the urinary bladder and seminal vesicles, respectively, as compared with the activity in the testis. Accordingly, CYP19A1 gene and P450arom protein expression was detected in those human tissues. Moreover, the data revealed that the expression of CYP19A1 gene is driven by promoters PII, I.4, and I.3 in the seminal vesicles, and by promoters PII and I.4 in the urinary bladder. Furthermore, the reporter gene expression in the seminal vesicles was androgen dependent: Castration decreased the expression ∼20 times, and testosterone treatment restored it to the level of an intact mouse. This reporter mouse model facilitates studies of tissue-specific regulation of the human CYP19A1 gene, and our data provide evidence for seminal vesicles as important sites for estrogen production in males.-Strauss, L., Rantakari, P., Sjögren, K., Salminen, A., Lauren, E., Kallio, J., Damdimopoulou, P., Boström, M., Boström, P. J., Pakarinen, P., Zhang, F. P., Kujala, P., Ohlsson, C., Mäkelä, S., Poutanen, M. Seminal vesicles and urinary bladder as sites of aromatization of androgens in men, evidenced by a CYP19A1-driven luciferase reporter mouse and human tissue specimens.
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