scholarly journals Morphological Changes of Mammalian Nucleoli during Spermatogenesis and Their Possible Role in the Chromatoid Body Assembling

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Rita Luiza Peruquetti ◽  
Sebastião Roberto Taboga ◽  
Maria Tercília Vilela de Azeredo-Oliveira
Keyword(s):  
Germ Cells ◽  
Morphological Changes ◽  
Protein Accumulation ◽  
Cytoplasmic Organelle ◽  
Chromatoid Body ◽  
Germ Cell Differentiation ◽  
Significant Difference ◽  
Pachytene Spermatocytes ◽  
Nucleolar Cycle ◽  
Important Structure

Chromatoid body (CB) is a typical cytoplasmic organelle of germ cells, and it seems to be involved in RNA/protein accumulation for later germ-cell differentiation. Despite most of the events in mammals spermatogenesis had been widely described in the past decades and the increase in the studies related to the CB molecular composition and physiology, the origins and functions of this important structure of male germ cells are still unclear. The aims of this study were to describe the nucleolar cycle and also to find some relationship between the nucleolar organization and the CB assembling during the spermatogenesis in mammals. Cytochemical and cytogenetics analysis showed nucleolar fragmentation in post-pachytene spermatocytes and nucleolar reorganization in post-meiotic spermatids. Significant difference in the number and in the size of nucleoli between spermatogonia and round spermatids, as well as differences in the nucleolar position within the nucleus were also observed. Ultrastructural analysis showed the CB assembling in the cytoplasm of primary spermatocytes and the nucleolar fragmentation occurring at the same time. In conclusion our results suggest that the CB may play important roles during the spermatogenesis process in mammals and that its origin may be related to the nucleolar cycle during the meiotic cell cycle.

scholarly journals 193 TESTIS TISSUE XENOGRAFTING TO PRESERVE GERM CELLS FROM A CLONED BANTENG CALF

2005 ◽  
Vol 17 (2) ◽  
pp. 247 ◽  
Author(s):  
A. Honaramooz ◽  
W. Zeng ◽  
R. Rathi ◽  
J. Koster ◽  
O. Ryder ◽  
...  
Keyword(s):  
Germ Cell ◽  
Germ Cells ◽  
Seminal Vesicles ◽  
Male Germ Cells ◽  
Newborn Animal ◽  
Immunodeficient Mice ◽  
Germ Cell Differentiation ◽  
Pachytene Spermatocytes ◽  
The Right ◽  
Testis Tissue

In April 2003, two banteng (Bos javonicus) calves were born after heterologous nuclear transfer of donor cells from a genetically valuable individual frozen in 1978. One of the cloned banteng calves died at one week of age. The calf was found to have one scrotal and one abdominally cryptorchid testis. In an attempt to preserve male germ cells from this valuable animal, parts of each testis were shipped on ice to the University of Pennsylvania for xenografting. Grafting of testis tissue from immature domestic animals and monkeys under the back skin of immunodeficient mice can result in complete spermatogenesis, albeit with different levels of efficiency in different species. The objective of this experiment was to investigate if grafting of immature banteng testis tissue would result in spermatogenesis in a mouse host. Small fragments of tissue (about 1 mm, 3 each) from both testes were grafted under the back skin (4 pieces of scrotal testis on the right side and 4 pieces of retained testis on the left side) of 6 castrated male immunodeficient mice. Histological examination of the testis xenografts was performed 3, 6, 9, 12, and 15 months after transplantation. Weight of the seminal vesicles in the host mouse was recorded as an indicator of bioactive testosterone produced by the xenografts. At the time of grafting, both testes contained seminiferous cords with immature Sertoli cells and gonocytes. At 3, 6, and 9 months after grafting, pachytene spermatocytes were present in the xenografts of the scrotal testis whereas no germ cell differentiation was observed in grafts from the retained testis. However, spermatogenesis in grafts of the scrotal testis did not proceed further through meiosis in grafts analyzed at 12 and 15 months after grafting, with pachytene spermatocytes still the most advanced germ cell type present in grafts recovered 15 months after grafting. The weight of the seminal vesicles in the castrated host mice was restored to pre-castration values showing that xenografts were releasing bioactive testosterone. These results indicate that banteng spermatogenesis was initiated in the mouse host but became arrested at meiosis as observed previously in xenografts of immature bovine or equine testis. Therefore, haploid germ cells could not be recovered. This represents the first example of trying to preserve fertility from a rare, valuable newborn animal by testis tissue xenografting. While xenografting presents a previously unavailable option for preservation of male germ cells from immature individuals, the efficiency of sperm production in testis xenografts appears to be variable and has to be determined empirically for different donor species. This work was supported by USDA 03-35203-13486.

scholarly journals Gonadal status of male recipient mice influences germ cell development in immature buffalo testis tissue xenograft

Reproduction ◽  
2012 ◽  
Vol 143 (1) ◽  
pp. 59-69 ◽  
Author(s):  
Niranjan Reddy ◽  
Ranjeet Singh Mahla ◽  
Revanth Thathi ◽  
Sanjay Kumar Suman ◽  
Jedy Jose ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
Germ Cell ◽  
Germ Cells ◽  
Serum Testosterone ◽  
Intact Mouse ◽  
Germ Cell Differentiation ◽  
Pachytene Spermatocytes ◽  
Gonadal Status ◽  
Tubule Diameter ◽  
Testis Tissue

Growth and development of immature testis xenograft from various domestic mammals has been shown in mouse recipients; however, buffalo testis xenografts have not been reported to date. In this study, small fragments of testis tissue from 8-week-old buffalo calves were implanted subcutaneously onto the back of immunodeficient male mouse recipients, which were either castrated or left intact (non-castrated). The xenografts were retrieved and analyzed 12 and 24 weeks later. The grafted tissue survived and grew in both types of recipient with a significant increase in weight and seminiferous tubule diameter. Recovery of grafts from intact recipients 24 weeks post-grafting was significantly lower than that from the castrated recipients. Seminal vesicle indices and serum testosterone levels were lower in castrated recipients at both collection time points in comparison to the intact recipients and non-grafted intact mouse controls. Pachytene spermatocytes were the most advanced germ cells observed in grafts recovered from castrated recipients 24 weeks post-grafting. Complete spermatogenesis, as indicated by the presence of elongated spermatids, was present only in grafts from intact recipients collected 24 weeks post-grafting. However, significant number of germ cells with DNA damage was also detected in these grafts as indicated by TUNEL assay. The complete germ cell differentiation in xenografts from intact recipients may be attributed to efficient Sertoli cell maturation. These results suggest that germ cell differentiation in buffalo testis xenograft can be completed by altering the recipient gonadal status.

scholarly journals Chromatoid body and small RNAs in male germ cells

Reproduction ◽  
2011 ◽  
Vol 142 (2) ◽  
pp. 195-209 ◽  
Author(s):  
Oliver Meikar ◽  
Matteo Da Ros ◽  
Hanna Korhonen ◽  
Noora Kotaja
Keyword(s):  
Germ Cells ◽  
Small Rna ◽  
Small Rnas ◽  
Rna Binding ◽  
Germ Line ◽  
Rna Binding Proteins ◽  
Current Knowledge ◽  
Chromatoid Body ◽  
Male Germ Cells ◽  
Germ Cell Differentiation

The chromatoid body (CB) is a germ granule in the cytoplasm of postmeiotic haploid round spermatids that is loaded with RNA and RNA-binding proteins. Following the discovery of small non-coding RNA-mediated gene regulation and the identification of PIWI-interacting RNAs (piRNAs) that have crucial roles in germ line development, the function of the CB has slowly begun to be revealed. Male germ cells utilise small RNAs to control the complex and specialised process of sperm production. Several microRNAs have been identified during spermatogenesis. In addition, a high number of piRNAs are present both in embryonic and postnatal male germ cells, with their expression being impressively induced in late meiotic cells and haploid round spermatids. At postmeiotic stage of germ cell differentiation, the CB accumulates piRNAs and proteins of piRNA machinery, as well as several other proteins involved in distinct RNA regulation pathways. All existing evidence suggests a role for the CB in mRNA regulation and small RNA-mediated gene control, but the mechanisms remain uncharacterised. In this review, we summarise the current knowledge of the CB and its association with small RNA pathways.

scholarly journals Morphological Changes of the Hip Commonly Associated With Femoroacetabular Impingement Are Not Correlated With Rotational Range of Hip Motion in Elite Soccer Athletes

2021 ◽  
pp. 194173812097366
Author(s):  
André Orlandi Bento ◽  
Guilherme Falótico ◽  
Keelan Enseki ◽  
Ronaldo Alves Cunha ◽  
Benno Ejnisman ◽  
...  
Keyword(s):  
Femoroacetabular Impingement ◽  
Lower Limb ◽  
Clinical Relevance ◽  
Morphological Changes ◽  
Alpha Angle ◽  
Soccer Players ◽  
Level Of Evidence ◽  
Rotational Movement ◽  
Professional Soccer ◽  
Significant Difference

Background: Morphological changes characteristic of femoroacetabular impingement (FAI) are common in soccer players. However, the clinical relevance of such anatomical variations is still not well-defined. Hypothesis: We hypothesized that high alpha angle values and/or acetabular retroversion index (ARI) are correlated with rotational range of motion (ROM) of the hip and that there are clinical-radiological diferences between the dominant lower limb (DLL) and nondominant lower limb (NDLL) in professional soccer players. Study Design: Cross-sectional. Level of Evidence: Level 3. Methods: A total of 59 male professional soccer players (average age 25.5 years, range 18-38 years) were evaluated in the preseason. As main outcome measures, we evaluated the alpha angle and the ARI and hip IR and ER ROM with radiographic analysis. Results: The measurements taken on DLL and NDLL were compared and a significant difference was found between the sides in the ER ( P = 0.027), where the DLL measures were 1.54° (95% CI, 0.18-2.89) greater than the NDLL. There were no significant differences between the sides in the measures of IR ( P > 0.99), total ROM ( P = 0.07), alpha angle ( P = 0.250), and ARI ( P = 0.079). The correlations between the rotation measurements and the alpha angle in each limb were evaluated and the coefficient values showed no correlation; so also between the ARI and rotation measures. Conclusion: Morphological changes of the femur or acetabulum are not correlated with hip IR and ER ROM in male professional soccer players. ER on the dominant side was greater than on the nondominant side. There was no significant difference in the other measurements between sides. Clinical Relevance: In clinical practice, it is common to attribute loss of hip rotational movement to the presence of FAI. This study shows that anatomical FAI may not have a very strong influence on available hip rotational movement in professional soccer athletes.

scholarly journals Evidence for diagnosis of early chronic pancreatitis after three episodes of acute pancreatitis: a cross-sectional multicentre international study with experimental animal model

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Péter J. Hegyi ◽  
Alexandra Soós ◽  
Emese Tóth ◽  
Attila Ébert ◽  
Viktória Venglovecz ◽  
...  
Keyword(s):  
Acute Pancreatitis ◽  
Chronic Pancreatitis ◽  
Morphological Changes ◽  
International Study ◽  
Study Data ◽  
Cross Sectional ◽  
Clinical Biomarkers ◽  
Stage Disease ◽  
Significant Difference ◽  
End Stage

AbstractChronic pancreatitis (CP) is an end-stage disease with no specific therapy; therefore, an early diagnosis is of crucial importance. In this study, data from 1315 and 318 patients were analysed from acute pancreatitis (AP) and CP registries, respectively. The population from the AP registry was divided into AP (n = 983), recurrent AP (RAP, n = 270) and CP (n = 62) groups. The prevalence of CP in combination with AP, RAP2, RAP3, RAP4 and RAP5 + was 0%, 1%, 16%, 50% and 47%, respectively, suggesting that three or more episodes of AP is a strong risk factor for CP. Laboratory, imaging and clinical biomarkers highlighted that patients with RAP3 + do not show a significant difference between RAPs and CP. Data from CP registries showed 98% of patients had at least one AP and the average number of episodes was four. We mimicked the human RAPs in a mouse model and found that three or more episodes of AP cause early chronic-like morphological changes in the pancreas. We concluded that three or more attacks of AP with no morphological changes to the pancreas could be considered as early CP (ECP).The new diagnostic criteria for ECP allow the majority of CP patients to be diagnosed earlier. They can be used in hospitals with no additional costs in healthcare.

scholarly journals Cell-type-specific regulation of genes involved in testicular lipid metabolism: fatty acid-binding proteins, diacylglycerol acyltransferases, and perilipin 2

Reproduction ◽  
2013 ◽  
Vol 146 (5) ◽  
pp. 471-480 ◽  
Author(s):  
Gerardo M Oresti ◽  
Jesús García-López ◽  
Marta I Aveldaño ◽  
Jesús del Mazo
Keyword(s):  
Fatty Acid ◽  
Cell Differentiation ◽  
Germ Cell ◽  
Germ Cells ◽  
Sertoli Cells ◽  
Fatty Acid Binding Proteins ◽  
Cell Type ◽  
Fatty Acid Binding ◽  
Germ Cell Differentiation ◽  
Perilipin 2

Male germ cell differentiation entails the synthesis and remodeling of membrane polar lipids and the formation of triacylglycerols (TAGs). This requires fatty acid-binding proteins (FABPs) for intracellular fatty acid traffic, a diacylglycerol acyltransferase (DGAT) to catalyze the final step of TAG biosynthesis, and a TAG storage mode. We examined the expression of genes encoding five members of the FABP family and two DGAT proteins, as well as the lipid droplet protein perilipin 2 (PLIN2), during mouse testis development and in specific cells from seminiferous epithelium.Fabp5expression was distinctive of Sertoli cells and consequently was higher in prepubertal than in adult testis. The expression ofFabp3increased in testis during postnatal development, associated with the functional differentiation of interstitial cells, but was low in germ cells.Fabp9, together withFabp12, was prominently expressed in the latter. Their transcripts increased from spermatocytes to spermatids and, interestingly, were highest in spermatid-derived residual bodies (RB). Both Sertoli and germ cells, which produce neutral lipids and store them in lipid droplets, expressedPlin2. Yet, whileDgat1was detected in Sertoli cells,Dgat2accumulated in germ cells with a similar pattern of expression asFabp9. These results correlated with polyunsaturated fatty acid-rich TAG levels also increasing with mouse germ cell differentiation highest in RB, connecting DGAT2 with the biosynthesis of such TAGs. The age- and germ cell type-associated increases inFabp9,Dgat2, andPlin2levels are thus functionally related in the last stages of germ cell differentiation.

Pax-2 is required for mesenchyme-to-epithelium conversion during kidney development

Development ◽  
1993 ◽  
Vol 119 (3) ◽  
pp. 711-720 ◽  
Author(s):  
U. W. Rothenpieler ◽  
G. R. Dressler
Keyword(s):  
Kidney Development ◽  
Morphological Changes ◽  
Cell Formation ◽  
Protein Accumulation ◽  
Metanephric Mesenchyme ◽  
Loss Of Function ◽  
Organ Cultures ◽  
Protein Levels ◽  
Differentiated Cells ◽  
Mesenchyme Cells

The conversion of mesenchyme to epithelium during the embryonic development of the mammalian kidney requires reciprocal inductive interactions between the ureter and the responding metanephric mesenchyme. The Pax-2 gene is activated in the mesenchyme in response to induction and is subsequently down-regulated in more differentiated cells derived from the mesenchyme. Pax-2 belongs to a family of genes, at least three of which encode morphogenetic regulatory transcription factors. In order to determine the role of Pax-2 during kidney development, we have generated a loss- of-function phenotype using antisense oligonucleotides in mouse kidney organ cultures. These oligonucleotides can specifically inhibit Pax-2 protein accumulation in kidney mesenchyme cells, where the intracellular concentrations are maximal. The kidney organ cultures were stained with uvomurulin and laminin antibodies as markers for epithelium formation. With significantly reduced Pax-2 protein levels, kidney mesenchyme cells fail to aggregate and do not undergo the sequential morphological changes characteristic of epithelial cell formation. The data demonstrate that Pax-2 function is required for the earliest phase of mesenchyme-to-epithelium conversion.

scholarly journals Fumonisin B1 Production by Fusarium Species and Mycotoxigenic Effect on Larval Zebrafish

2020 ◽  
Vol 31 (3) ◽  
pp. 91-107 ◽  
Author(s):  
Najihah Azman ◽  
Nur Ain Izzati Mohd Zainudin ◽  
Wan Norhamidah Wan Ibrahim
Keyword(s):  
Liquid Chromatography ◽  
Danio Rerio ◽  
Morphological Changes ◽  
Fusarium Species ◽  
Fumonisin B1 ◽  
Larval Zebrafish ◽  
Zebrafish Larvae ◽  
Significant Difference ◽  
Successful Amplification ◽  
Fast Liquid Chromatography

Fumonisin B1 (FB1) is a common mycotoxin produced by Fusarium species particularly F. proliferatum and F. verticillioides. The toxin produced can cause adverse effects on humans and animals. The objectives of this study were to detect the production of FB1 based on the amplification of FUM1 gene, to quantify FB1 produced by the isolates using Ultra-fast Liquid Chromatography (UFLC) analysis, to examine the embryotoxicity effect of FB1 and to determine EC50 toward the larvae of zebrafish (Danio rerio). Fifty isolates of Fusarium species were isolated from different hosts throughout Malaysia. Successful amplification of the FUM1 gene showed the presence of this gene (800 bp) in the genome of 48 out of 50 isolates. The highest level of FB1 produced by F. proliferatum isolate B2433 was 6677.32 ppm meanwhile F. verticillioides isolate J1363 was 954.01 ppm. From the assessment of embryotoxicity test of FB1 on larvae of zebrafish, five concentrations of FB1 (0.43 ppm, 0.58 ppm, 0.72 ppm, 0.87 ppm and 1.00 ppm) were tested. Morphological changes of the FB1 exposed-larvae were observed at 24 to 168 hpf. The mortality rate and abnormality of zebrafish larvae were significantly increased at 144 hpf exposure. Meanwhile, the spontaneous tail coiling showed a significant difference. There were no significant differences in the heartbeat rate. As a conclusion, the presence of FUM1 in every isolate can be detected by FUM1 gene analysis and both of the species produced different concentrations of FB1. This is the first report of FB1 produced by Fusarium species gave a significant effect on zebrafish development.

scholarly journals Interactome analyses reveal profound proteasome structural and functional rearrangements throughout mammalian spermatogenesis

2021 ◽  
Author(s):  
Dusan Zivkovic ◽  
Angelique Sanchez Dafun ◽  
Thomas Menneteau ◽  
Adrien Schahl ◽  
Sandrine Lise ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Germ Cell ◽  
Germ Cells ◽  
Protein Assembly ◽  
Homologous Chromosomes ◽  
High Proteolytic Activity ◽  
Complex Processes ◽  
Germ Cell Differentiation ◽  
Mechanism Function

During spermatogenesis, spermatogonia undergo a series of mitotic and meiotic divisions on their path to spermatozoa. To achieve this, a succession of complex processes requiring high proteolytic activity are in part orchestrated by the proteasome. The spermatoproteasome (s20S) is a proteasome subtype specific to the developing gametes, in which the gamete-specific α4s subunit replaces the α4 isoform found in the constitutive proteasome (c20S). Although the s20S is conserved across species and was shown to be crucial for germ cell development, its mechanism, function and structure remain incompletely characterized. Here, we used advanced mass spectrometry (MS) methods to map the composition of proteasome complexes and their interactomes throughout spermatogenesis. We observed that the s20S becomes highly activated as germ cells enter meiosis, mainly through association with proteasome activators PA200 and 19S. Additionally, the proteasome population shifts from predominantly c20S (98%) to predominantly s20S (>82-92%) during differentiation, presumably due to the shift from α4 to α4s expression. We confirmed that s20S, but not c20S, interacts with components of the synaptonemal complex, the multi-protein assembly that connects homologous chromosomes during meiosis. In vitro, s20S preferentially bind to 19S, and displayed higher trypsin- and chymotrypsin-like activities, both with and without PA200 activation. Moreover, using MS methods to monitor protein dynamics, we identified significant differences in domain flexibility between α4 and α4s. We propose that these differences induced by α4s incorporation result in significant changes in the way the s20S interacts with its partners, and dictate its role in germ cell differentiation.

scholarly journals MON-161 Body Weight Reduction Not Always Reduced Adrenal Gland Volume in Obese Patients

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Tao Chen
Keyword(s):  
Weight Loss ◽  
Body Weight ◽  
Sleeve Gastrectomy ◽  
Adrenal Gland ◽  
Morphological Changes ◽  
Normal Weight ◽  
Obese Patients ◽  
Gland Volume ◽  
Significant Difference ◽  
Adrenal Gland Volume

Abstract Recent studies have shown that obesity is a major risk factor for idiopathic hyperaldosteronism (IHA). IHA patients have greater AGV than normal controls. However, it is unclear whether such changes are caused by obesity and whether losing weight could reverse the morphological and functional abnormalities of the adrenal gland. This study was to investigate the association of obesity with adrenal gland volume (AGV) and the effects of weight loss on AGV. This study recruited obese patients (N=25) who underwent sleeve gastrectomy and age- and sex-matched normal-weight (N=25) and overweight healthy volunteers (HV) (N=21). Thin-slice computed tomography was used to evaluate adrenal morphological changes. AGV was measured semiautomatically based on the digital imaging and communications in medicine (DICOM) image. The effects of weight loss on AGV were evaluated in patients for one year or more after sleeve gastrectomy. The results showed that left, right and total AGV were larger in obese patients than those in overweight and normal- weight HVs (6.77±0.36, 5.76±0.31, and 12.53±0.64 cm3 vs. 3.88±0.14, 3.09± 0.13 and 6.97± 0.24 cm3 vs. 3.38±0.23, 2.67±0.15 and 6.04±0.36 cm3). No statistically significant difference was identified between overweight and normal-weight HVs. Sleeve gastrectomy significantly reduced body weight (-27.1±2.5 kg), left AGV (-0.80±0.26 cm3), and right AGV (-0.88±0.20 cm2). However, the adrenal volume in five patients was not reduced, despite significant weight loss postsurgery. In brief, obesity leads to increased AGV, and in some cases, this effect seems to be irreversible. We speculate that obesity causes permanently adrenal morphological changes (increased volume or hyperplasia), and under certain circumstances, it results in excessive aldosterone secretion via altered adipokines (leptin, CTRP1, etc.).

Sign in / Sign up

Export Citation Format

Share Document