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1.
Wenyang YU Sijie FAN Xi WANG Jueyu ZHU Zhengrong YUAN Yingying HAN Haolin ZHANG Qiang WENG 《Integrative zoology》2023,18(1):76-92
The purpose of this study was to explore the variations in the circulating leptin concentrations of the wild ground squirrels in relation to seasonal changes in testicular activities. Hematoxylin-eosin staining showed all types of elongated spermatids and spermatogenic cells existed in the testis in April, while the primary spermatocytes and spermatogonia were most advanced stages of germ cells in June. In addition, the primary spermatocytes, secondary spermatocytes, and spermatogonia were most advanced stages of germ cells in September. The highest circulating leptin concentration was consistent with the maximum body weight results from accumulation of adipose tissue in September. The mRNA expression level of leptin receptor (Ob-R) and STAT3 was lowest in June, raised in September, and remained increased in April. Ob-R and STAT3 were stronger staining in the Leydig cells in July. Moreover, the concentrations of testosterone (T) showed the maximum values in April, the minimum values in June, and significant increases in September. Furthermore, it is worth noting that the levels of T increased with the mRNA levels of Ob-R, STAT3, StAR, and testicular steroidogenic enzymes (3β-HSD, P450c17, and P450scc). Moreover, RNA-seq analyses of testis during the different periods showed that a total of 4209 genes were differentially expressed genes (DEGs); further analysis revealed that DEGs related with the Jak/STAT pathways and reproduction were altered. Taken together, the results suggested that the leptin regulated testicular function through the Jak/STAT pathways and testicular steroidogenic factor expressions. 相似文献
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3.
The estrogenic and antioxidant effects of the phytoestrogen daidzein (DAI) on germ cell proliferation were evaluated by a chicken ovarian germ-somatic cell coculture model. Ovarian cells were dispersed from 18-day-old embryos, cultured in serum-free McCoy's 5A medium and challenged with DAI alone or in combinations with estrogen receptor antagonist tamoxifen for 48 h. The number of germ cells was counted and the proliferating cells were identified by immunocytochemistry of proliferating cell nuclear antigen (PCNA). The labeling index (LI) was determined for germ cells. Results showed that DAI significantly increased the number of germ cells (P<0.05) and this stimulating effect was inhibited by tamoxifen in a dose-dependent manner. Furthermore, PCNA-LI of germ cells displayed similar changes with the number of germ cells. To estimate the antioxidant action of DAI, ovarian cells were exposed to the reactive oxygen species (ROS)-producing system hypoxanthine/xanthine oxidase (HX/XO). The changes of superoxide dismutase (SOD) activity and glutathione (GSH) level were measured for estimation of the antioxidant status. Ovarian cells were severely damaged by free radicals and this deteriorating effect could be prevented by DAI. Moreover, HX/XO-induced decrease in SOD activity and GSH level was restored by DAI (P<0.05). These results indicated that DAI promoted proliferation of cultured ovarian germ cells by estrogenic action and attenuated ROS-induced toxicity by antioxidant action in embryonic chickens. 相似文献
4.
Stimulating effects of androgen on proliferation of cultured ovarian germ cells through androgenic and estrogenic actions in embryonic chickens 总被引：3，自引：0，他引：3
The effect of androgen on germ cell proliferation was evaluated by a chicken ovarian germ–somatic cell co-culture model and the mechanisms were explored. Ovarian cells were dispersed from 18-day-old embryos, cultured in serum-free McCoy's 5A medium and challenged with testosterone (T) alone or in combinations with androgen receptor antagonist Flutamide, estrogen receptor antagonist Tamoxifen or aromatase inhibitor Letrozole for 48 h. Germ cells were identified by c-kit immunocytochemistry. The number of germ cells was counted and the proliferating cells were identified by immunocytochemistry of proliferating cell nuclear antigen (PCNA). The labeling index (LI) was determined for germ cells. Results showed that T (10−7 to 10−6 M) significantly increased the number of germ cells (P < 0.05) and this stimulating effect was inhibited by Flutamide (10–1000 ng/ml), Tamoxifen (10–1000 ng/ml) or Letrozole (10−9 to 10−7 M) in a dose-dependent manner. Furthermore, PCNA-LI of germ cells displayed similar changes with the numbers of germ cells. These results indicated that T-stimulated proliferation of cultured ovarian germ cells through both, androgenic and estrogenic actions in embryonic chickens. 相似文献
5.
贵州香猪睾丸发育中支持细胞和生精细胞数量变化观察 总被引：1，自引：0，他引：1
为了解香猪睾丸发育过程中生殖细胞和支持细胞数变化规律,用手术取出30,40,50,70,90和110日龄(每个年龄组n=3～4)香猪右侧睾丸,经中性多聚甲醛固定,石蜡包埋,组织切片采用免疫组化SP法,用单克隆抗体GATA-4检测睾丸支持细胞的特异生长转录因子-4,经DAB显色、苏木素复染。光镜下核呈棕色者为支持细胞,核呈蓝色者则为生殖细胞;经显微照相并用Scion image软件测量生精小管及管壁面积。结果:30～110日龄睾丸支持细胞数维持在稳定水平(P>0.05),而生殖细胞数随日龄增加而增多,70日龄生殖细胞数快速增多(P<0.05),持续到110日龄。同样,从70日龄开始睾丸生精小管和管壁面积显著性增大(P<0.05)。香猪睾丸支持细胞快速增殖发生在30日龄前,而生殖细胞数随着日龄的增长而增多。 相似文献
6.
Fujihara M Kim SM Minami N Yamada M Imai H 《The Journal of reproduction and development》2011,57(3):355-364
The transition from male primitive germ cells (gonocytes) to type A spermatogonia in the neonatal testis is the initial process and a crucial process in spermatogenesis. However, in large domestic animals, the physiological and biochemical characteristics of germ cells during the developmental processes remain largely unknown. In this study, we characterized bovine germ cells in the developing testis from the neonatal stage to the adult stage. The binding of the lectin Dolichos biflorus agglutinin (DBA) and the expression of ubiquitin carboxyl-terminal hydrolase 1 (UCHL1) were restricted to gonocytes in the neonatal testis and spermatogonia in the adult testis. Gonocytes also expressed a germ cell marker (VASA) and stem cell markers (NANOG and OCT3/4), while the expressions of these markers in the adult testis were restricted to differentiated spermatic cells and were rarely expressed in spermatogonia. We subsequently utilized these markers to characterize gonocytes and spermatogonia after culture in vitro. Spermatogonia that were collected from the adult testis formed colonies in vitro only for one week. On the other hand, gonocytes from the neonatal testis could proliferate and form colonies after every passage for 1.5 months in culture. These colonies retained undifferentiated states of gonocytes as confirmed by the expression of both germ cell and stem cell markers. Moreover, a transplantation assay using immunodeficient mice testes showed that long-term cultured cells derived from gonocytes were able to colonize in the recipient testis. These results indicated that bovine gonocytes could maintain germ cell and stem cell potential in vitro. 相似文献
7.
Isolation and culture of rabbit primordial germ cells 总被引：2，自引：0，他引：2
Kakegawa R Teramura T Takehara T Anzai M Mitani T Matsumoto K Saeki K Sagawa N Fukuda K Hosoi Y 《The Journal of reproduction and development》2008,54(5):352-357
Primordial germ cells (PGCs) are embryonic precursors of the gametes of adult animals and are considered stem cells of the germline. Since their proliferation in vitro correlates well with the schedule of developmental changes in vivo, they might be interesting research tools for genomic imprinting, germ-cell tumors and fertility. Furthermore, once primordial germ cells are separated and placed on a feeder layer with cytokines, they become cultured pluripotent cell lines called embryonic germ (EG) cells. EG cells share several important characteristics with embryonic stem (ES) cells as they can also contribute to the germ line of chimeras. To investigate the characteristics of PGCs and establish rabbit EG (rEG) cells, we cultured rabbit PGCs (rPGCs) in vitro with various combinations of leukemia inhibitory factor (LIF), basic fibroblast growth factor (bFGF) and forskolin on inactivated mouse embryonic fibroblast (MEF) feeder layers. The present study found PGC proliferation in early cultures and induction of rEG-like colonies. These cells expressed pluripotent markers, such as alkaline phosphatase activity, OCT-4, Sox-2 and SSEA-1, in the undifferentiated state; however, the cells did not develop into a teratoma when injected into the kidney capsules of SCID mice, although the restricted differentiation potentials to neural cells were determined via embryoid body formation. From these characteristics and further characterization of the germ stem cell markers Vasa, SCP-1 and SCP-3, we suggested that these were hybrid cells with characteristics somewhere between PGC and EG cells. 相似文献
8.
Y Kanai H Kawakami M Kanai-Azuma M Kurohmaru H Hirano Y Hayashi 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(2):297-303
Changes in the intracellular and cell surface localization of Lewis x (Le(x)) determinants in germ cells during fetal development in mice were examined by light and electron microscopy. Light microscopically, in undifferentiated gonads on day 12 post coitum (p.c.), the anti-Le(x) monoclonal antibody (MAb) was specifically bound to the plasma membranes and to the cytoplasmic granule-like structures of germ cells. In the testes on day 13 p.c., most of the germ cells were enclosed within the testicular cords and showed an MAb-positive reaction which was restricted mainly to the cytoplasmic granule-like structures. The reaction on the plasma membranes almost disappeared. On the other hand, the ectopic germ cells still showed a positive reaction on their plasma membranes. In the ovaries on day 13 p.c., the germ cells also exhibited positive reactions both on the plasma membranes and on the granule-like structures. Immunoelectron microscopic observations agreed well with these light microscopic observations in such a way that both the plasma membranes and the "small dense bodies" (SDB) were positive in undifferentiated gonads on day 12 p.c. In the germ cells organized into the testicular cords, the reaction to anti-Le(x) MAb became restricted to the SDB. These results may indicate that such intracellular changes in Le(x) determinants during germ cell differentiation are associated with the enclosure of germ cells within the testicular cords. 相似文献
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10.
González-Morán MG 《Domestic animal endocrinology》2007,33(2):154-166
The effect of the luteinizing hormone (LH) on the oogenesis of ovaries from newly-hatched chicks treated in vivo on days 13, 15, and 17 of embryonic development was analyzed. Changes in oogonial proliferation, meiotic prophase, degeneration of germ cells, and primordial follicular organization were determined. Results indicate that the total number of germ cells was not affected by the LH treatment, but significant differences existed in the number of oogonia and oocytes between the ovaries of control and LH-treated chicks. LH treatment increased the percentage of oocytes and diminished the percentage of oogonia. The mitotic activity of oogonia and degeneration of germ cells decreased, but the number of follicles during development increased in LH-treated ovaries. These findings suggest that LH treatment might trigger a cascade of endocrine events, resulting in inhibition of oogonial proliferation and induction of the meiotic prophase and follicle formation. 相似文献
11.
体外培养山羊50~68日龄雄性胎儿生殖细胞,并检测它们的碱性磷酸酶(AP)活性和Oct-4蛋白,探讨性别分化后的生殖细胞用于建立干细胞系的可行性及检测指标。当山羊胎儿睾丸细胞体外培养时,生殖细胞及其来源的细胞克隆均呈AP阴性和Oct-4蛋白阴性,其中有部分细胞克隆表现为AP假阳性。山羊胎儿生殖细胞克隆呈隆突状生长,多为圆形,与周围细胞界限分明,但克隆内细胞间界限不清。细胞克隆至少可以培养3代以上。研究结果显示,山羊雄性胎儿生殖细胞可以用于建立生殖系来源的干细胞系;AP和Oct-4蛋白不适宜用来检测体外培养的山羊胎儿生殖细胞及其来源的细胞系。 相似文献
12.
The Influence of Supplementation with Urea–Molasses Blocks on Weight Gain and Nematode Parasitism of Dairy Calves in Central Kenya 总被引：1，自引：0，他引：1
Waruiru RM 《Veterinary research communications》2004,28(4):307-315
The effect of feeding urea-molasses blocks (UMB) on the growth and gastrointestinal nematode parasitism of dairy weaner calves grazing on the same pasture was investigated on a farm in Thika District, central Kenya. Twenty-six female calves, with an average age of 9 months, were initially treated orally with albendazole (10 mg/kg body weight) and assigned into two groups: animals in group I were fed urea-molasses blocks (UMB) prepared using a cold process and those in group II were the controls. The UMB were given in the evening, when the animals returned from grazing, and were consumed during the night at a rate of 550 g/head per day. Supplementation was undertaken on three occasions for three consecutive months, between July and August 1999, and between January and March and July and September 2000. The body weights of the calves and the faecal egg counts were measured monthly and larval cultures were performed on positive faecal samples from each group. Significant differences (p < 0.05) were found in the cumulative weight gains of the two groups of calves from September onwards. The UMB group averaged (+/- SD) 311.2 +/- 14.9 g/day over the study period, while the control group averaged 235.7 +/- 23.5 g/day; the UMB group also reached breeding weight earlier (p < 0.05) than the control group. There was no significant difference (p > 0.05) in the faecal egg counts between the groups, the predominant genera of gastrointestinal nematodes in faecal cultures being Haemonchus spp. and Trichostrongylus spp. Other nematodes were Cooperia spp., Bunostomum spp. and Oesophagostomum spp. 相似文献
13.
Xinpeng Yang Yue Feng Yang Li Dake Chen Xuanyan Xia Jialian Li Fenge Li 《Reproduction in domestic animals》2021,56(3):416-426
Sertoli cells are the only somatic cells in the seminiferous epithelium which directly contact with germ cells. Sertoli cells exhibit polarized alignment at the basal membrane of seminiferous tubules to maintain the microenvironment for growth and development of germ cells, and therefore play a crucial role in spermatogenesis. Androgens exert their action through androgen receptor (AR) and AR signalling in the testis is essential for maintenance of spermatogonial numbers, blood–testis barrier integrity, completion of meiosis, adhesion of spermatids and spermiation. In the present study, we demonstrated that AR gene could promote the proliferation of immature porcine Sertoli cells (ST cells) and the cell cycle procession, and accelerate the transition from G1 phase into S phase in ST cells. Meanwhile, miR-124a could affect the proliferation and cell cycle procession of ST cells by targeting 3′-UTR of AR gene. Furthermore, AR bound to the RNF4 via AR DNA-binding domain (DBD) and we verified that RNF4 was necessary for AR to regulate the growth of ST cells. Above all, this study suggests that AR regulates ST cell growth via binding to RNF4 and miR-124a, which may help us to further understand the function of AR in spermatogenesis. 相似文献
14.
Pérez J García PM Hernández S Mozos E Cámara S Martínez-Moreno A 《Veterinary parasitology》2003,111(4):333-342
Histopathological changes and the distribution of T lymphocytes (CD3), B cells (CD79alpha) and IgG secreting plasma cells were recorded in the abomasum and abomasal lymph nodes of goats during early and late post-infection stages with one to four doses of Haemonchus contortus L3. The infiltration of eosinophils, mast cells, CD3(+) T lymphocytes, CD79alpha(+)B cells and IgG(+) plasma cells in the abomasal mucosa increased dramatically from 10dpi onwards, whereas globule leukocytes were observed only during chronic infection. In late post-infection stages abomasal infiltration of globule leukocytes, CD3(+) T lymphocytes, CD79alpha(+)B cells and IgG(+) plasma cells was significantly higher (P<0.05) in reinfected (groups 6-8) than in primarily infected goats (group 5). In the abomasal lymph nodes, marked hyperplasia of lymphoid follicles and medullary cords, with increase of CD3(+) T lymphocytes, CD79alpha(+)B cells and IgG(+) plasma cells was recorded from 10dpi (group 3) onwards. Worm burdens and the severe abomasal response during the late post-infection stages suggests that a rapid expulsion of nematodes did not occur. The prolonged time required for generating globule leukocytes suggested that immune mechanisms dependent of this cell type are of crucial importance in the protective immunity against H. contortus in goats. 相似文献
15.
Fas/FasL系统调控公牛精子发生的研究进展 总被引：1，自引：1，他引：0
牛的精子发生是一个特殊的雄性生殖细胞的分化、增殖和凋亡的过程。在这一过程中,生殖细胞总是不断地处于分化和凋亡的动态平衡之中。凋亡信号转导分子Fas和FasL组成的Fas/FasL系统不但在细胞自稳和疾病发生中具有重要作用,而且参与调控牛的精子发生。当Fas和FasL表达异常时,直接影响生殖细胞的发育和增殖。作者通过阐明Fas/FasL系统在牛精子发生过程中的调控机理,为提高种公牛的繁殖性能开创一条新的途径。 相似文献
16.
The immunohistochemical (IHC) localization of oestrogen receptor alpha (ERα) was studied in the developing left ovary of 14.5-day-old chick embryos. The study was focused in particular on distinguishing in cortex and medulla the different cell categories that proved positive to the reaction, in order to gain further understanding of gonadal cell interactions during ovarian development. Immunostained cells were observed in both the cortex and medulla, but the reactivity for ERα was discontinuous, probably due to variable cell requirements. In the cortex, positivity was observed in cells of the ovarian surface epithelium, in germ cells and in prefollicular cells. In the medulla, positivity was found in the following cell categories: interstitial cells, poorly differentiated somatic cord cells, including those delimiting lacunae, germ cells and their accompanying cells of epithelial origin. Furthermore, the IHC results showed that the intracellular localization of the antigen was cytoplasmic, nuclear, or both. The significance of ERα presence and intracellular localization was discussed in relation and as supplementary to previous research by various Authors. In particular, as regards the unusual cytoplasmic immunoreactivity, a gradual shift of ERα localization from cytoplasmic to nuclear during the embryonic period is suggested. 相似文献
17.
Noguchi J Ohnuma K Ozawa M Karja NW Fahrudin M Somfai T Kikuchi K Kaneko H 《The Journal of reproduction and development》2006,52(3):383-389
The ultimate goal of this study was to establish an in vitro system to produce sperms. To pursue this goal, immature porcine testicular cells were cultured in stereostructural form and cultured testicular cord was investigated morphologically. At 4 weeks of age, the seminiferous tubules of the porcine testes consisted of undifferentiated germ cells (gonocytes and undifferentiated spermatogonia) and immature Sertoli cells. The interstitial tissue was largely occupied by Leydig cells. The testes were enzymatically digested, and the dispersed cells were encapsulated with alginate either immediately or after freeze-thawing. The resulting testicular cell cords were cultured for up to 10 weeks. After 2 weeks of culture, Sertoli cells, which were identified by their inhibin-positive reaction in immunohistochemistry, and Leydig cells, which were identified by their morphological characteristics, were observed in the cords. Neither undifferentiated nor differentiated types of germ cells were detected. The number of cells in the cords progressively decreased during the culture period. In order to discover the fate of the Sertoli cells, the level of inhibin in the spent media was determined. Inhibin in the media was at a detectable level after 2 days of culture. The levels increased and peaked at 2 weeks. When frozen-thawed testicular cells were applied to the culture, the peak level was maintained for over 8 weeks, in contrast to the gradual decrease of inhibin level when fresh cells were cultured. These results indicate that the culture conditions can sustain the survival of Sertoli cells. Further improvement is required for proliferation and differentiation of germ cells. 相似文献
18.
Strongylus vulgaris populations in the cranial mesenteric arteries, caecum and colon were studied in 14 donkeys obtained from a communal area of the Zimbabwean highveld during July and November, 1986, and January and April 1987. Adult parasites were present in all animals and larvae in the cranial mesenteric arteries of 12 animals. Aged animals had high worm burdens. The number of adult parasites varied from 63 to 1255 (mean 382) and of larvae in the arteries from 0 to 181 (mean 69). The mean adult worm burdens were highest in July (400) and November (488), and lowest in April (107). The mean arterial larval burden was highest in July (130) and lowest in November (21). These observations indicate that infection with S. vulgaris takes place during the rainy season resulting in the heavy arterial larval population from January onwards and the heavy adult population during the dry season. 相似文献
19.
G. GONZALEZ-MORAN 《British poultry science》1998,39(1):128-132
1. Cell sub-populations of the ovary of newly-hatched chicks were assessed following follicle stimulating hormone (FSH) treatment during embryonic development. Changes in cell number and the amount of oestradiol in serum were determined. 2. White Leghorn chick embryos received 1 mug FSH applied to the chorioallantoic membrane at 13, 15, and 17 d of incubation. Within 24 h after hatching, animals were killed and blood was collected. The left ovary was immediately removed then weighed and processed by an enzymatic-mechanical dissociation method for total cell count. An air-drying method was also used for meiotic preparations to study the germinal cells. 3. The pre-follicular ovary is able to respond to FSH by inducing an increase both in the serum oestradiol concentration and in the number of steroidogenic cells and of poorly differentiated cells of the ovarian medulla. 4. FSH increases the number of oogonia, which are responsible for a sharp increase in the total population of germ cells in the FSH-treated ovary. 5. It is possible that FSH acts to increase the proliferation of oogonia and a delay in the meiotic prophase through a change in the microenvironment rather than by a direct effect on germ cells. 相似文献
20.
Nakamuta N Kobayashi S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(11):1365-1370
Proteins encoded by p63 gene a have structural similarity with tumor suppressor p53, and were thought to induce cell cycle arrest and apoptosis during development. The p63 proteins are also expressed in the basal cells of many epithelial tissues in the adult, and supposed to play important roles in maintaining the epidermal stem cells. Previously, we reported the p63 expression in the testis of mouse embryos, suggesting their involvement in the growth arrest and apoptosis of testicular germ cells (Nakamuta and Kobayashi, J. Vet. Med. Sci. 65:853-856). In this study, we investigated the timing of this p63 expression in the germ cells during migration and colonization to the gonads. Immunohistochemical analysis of mice from embryonic day (E) 7.5 to E12.5 demonstrated that p63 positive reactivity was seen as early as E8.5 when the founder cells of germ cells, primordial germ cells (PGCs), were located in the hind gut epithelium, but PGCs were negative for p63 at E7.5 when they first appeared. p63 is expressed as six isoforms, resulting from alternative splicing at C-terminus and by the use of two promoters that generate variations at N-terminal end. RT-PCR analyses suggested that different types of p63 mRNAs were likely to be expressed in PGCs during development. These results imply that p63 may be involved in the regulation of PGC development by controlling the gene expression required for their migration and colonization to the gonads. 相似文献