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1.
Poult Sci ; 102(12): 103068, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37778296

ABSTRACT

Cockfighting is popular worldwide, dating back to 2,800 BC. Primarily, 5 modern Chinese gamecock breeds exist, located in the northeast (Luxi and Henan), west (Turpan), south (Xishuangbanna), and southeast (Zhangzhou) of China. However, whether Chinese gamecocks were derived from a single origin or multiple origins remains controversial. Therefore, this study used next-generation resequencing data to elucidate the origin of Chinese gamecocks by constructing genome-wide and SRY-box transcription factor 5 (SOX5) gene phylogenetic trees. Data from 161 chickens from 27 breeds, including 9 gamecock breeds, were included. Before constructing the SOX5 gene tree, we validated that the pea-comb phenotype mutation in all gamecock breeds was attributed to copy number variation in intron 1 of the SOX5 gene, as previously reported. The specific region was chr1: 65,838,000 to 65,846,000. The phylogenetic tree results suggested that Zhangzhou and Xishuangbanna gamecocks have a monophyletic origin, while Luxi, Henan, and Turpan gamecocks have a common ancestor. Our study provides genome-wide evidence that Chinese gamecocks have multiple origins and advances the understanding of the genetic mechanisms of the pea-comb characteristic.


Subject(s)
Chickens , DNA Copy Number Variations , Animals , Chickens/genetics , Phylogeny , Mutation , China , Genetic Variation
2.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1868(10): 159378, 2023 10.
Article in English | MEDLINE | ID: mdl-37572997

ABSTRACT

Adipose-derived stem cells (ADSCs) that are enriched in adipose tissue with multilineage differentiation potential have become an important tool in therapeutic research and tissue engineering. Certain breeds of sheep exhibit a unique fat tail trait such that tail tissue accounts for approximately 10 % of body weight and can provide an excellent source of ADSCs. Here, we describe isolation of primary ADSCs from ovine embryonic fat tail tissues that displayed high self-renewal capacity, multilineage differentiation and excellent adipogenic ability. Through transcriptome analysis covering ADSCs differentiating into adipocytes, 37 transcription factors were involved in early transcriptional events that initiate a regulatory cascade of adipogenesis; the entire adipogenic activity consists of a reduction in proliferation ability and upregulation of genes related to lipid generation and energy metabolism, as well as several genes associated with myogenesis. Furthermore, Comparative transcriptome analysis across species (sheep, human, and mouse) revealed enhanced basal metabolic ability in differentiating ovine ADSCs, which may relate to the excellent adipogenic capability of these cells. We also identified a small evolutionarily conserved gene set, consisting of 21 and 22 genes exhibiting increased and decreased expression, respectively. Almost half (20) of these genes have not previously been reported to regulate adipogenesis in mammals. In this study, we identified important regulators that trigger ovine adipocyte differentiation, main biological pathways involved in adipogenesis as well as the evolutionarily conserved genes governing adipogenic process across species. Our study provides a novel excellent biomaterial and novel genes regulating adipogenesis for cellular transplantation therapy and investigations of fat metabolism.


Subject(s)
Adipocytes , Adipogenesis , Animals , Sheep/genetics , Mice , Humans , Adipogenesis/genetics , Adipose Tissue , Gene Expression Profiling , Stem Cells , Mammals
3.
Yi Chuan ; 45(7): 545-552, 2023 Jul 20.
Article in English | MEDLINE | ID: mdl-37503579

ABSTRACT

Animal genetic resources in the world are rich and varied. Local species have strong adaptability to the local environment. They are precious resources, and need to be protected by the whole world. In this paper, we summarize the current situation of conservation activities of livestock and poultry resources abroad, including the relevant policies and measures, financial support, genetic material conservation, research projects, and the benefits of conservation animal genetic resources. The actions of conservation of animal genetic resources reflects the increasing recognition of the importance of biodiversity by people around the world. The variety of conservation activities of genetic materials in the world and its benefits reflect that the concept of biodiversity has already been accepted by public and the government. Conservation of animal genetic resources is the primary action for the revitalization of Chinese seed industry. This paper has enlightenment significance for strengthening the conservation of animal genetic resources in China.


Subject(s)
Conservation of Natural Resources , Livestock , Animals , China , Biodiversity , Poultry/genetics
4.
Small ; 19(37): e2300926, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37150851

ABSTRACT

Metal single-atom and internal structural defects typically coexist in M-N-C materials obtained through the existing basic pyrolysis processes. Identifying a correlation between them to understand the structure-activity relationship and achieve efficient catalytic performance is important, particularly for the rare-earth (RE) elements with rich electron orbitals and strong coordination capabilities. Herein, a novel single-atom catalyst based on the RE element lutetium is successfully synthesized on a N-C support. Structural and simulation analyses demonstrate that the formation of a LuN6 structural site with an individual defect because of pyrolysis is thermodynamically favorable in Lu-N-C. Using KHCO3 -based electrolytes facilitates the fall of the K+ cations into the defective sites of Lu-N-C, thus enabling improved CO2 capture and activation, which increases the catalyst conductivity for Lu-N-C. In this study, the catalyst exhibits a Faradaic efficiency of 95.1% for CO at a current density of 18.2 mA cm-2 during carbon dioxide reduction reaction. This study thus provides new insights into understanding RE-N-C materials for energy utilization.

5.
Poult Sci ; 102(7): 102766, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37229885

ABSTRACT

Genomic admixture is a widespread phenomenon among domestic animal breeds, including chickens. However, reports on admixture within Chinese gamecocks or other indigenous chickens are limited. This study focuses on the population genetic structure and admixture of 5 Chinese gamecock breeds and the admixture with 9 other indigenous Chinese chicken breeds. Our results showed that Turpan and Henan gamecocks were grouped into one cluster, whereas Luxi, Zhangzhou, and Xishuangbanna gamecocks were grouped into the other cluster. Gene flow occurred between Xishuangbanna and Turpan and Turpan and Luxi gamecocks. Simultaneously, gene flow was observed between gamecocks and indigenous chickens, such as Xishuangbanna and Wenchang. Ancestral component analysis indicated that modern domestic chickens in southern China played an important role in the history of the domestication of modern Chinese gamecock. Our study will be helpful in better understanding the domestication and evolution of Chinese gamecock.


Subject(s)
Chickens , Genetic Variation , Animals , Chickens/genetics , Genome , Genomics , China , Polymorphism, Single Nucleotide
6.
Small ; 19(38): e2301558, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37118852

ABSTRACT

Electrochemical CO2  reduction reaction (CO2 RR) is an effective approach to address CO2  emission, promote recycling, and synthesize high-value multi-carbon (C2+ ) chemicals for storing renewable electricity in the long-term. The construction of multilayer-bound nanoreactors to achieve management of intermediate CO is a promising strategy for tandem to C2+ products. In this study, a series of Ag@Cu2 O nanoreactors consisting of an Ag-yolk and a multilayer confined Cu shell is designed to profile electrocatalytic CO2 RR reactions. The optimized Ag@Cu2 O-2 nanoreactor exhibits a 74% Faradaic efficiency during the C2+ pathway and remains stable for over 10 h at a bias current density of 100 mA cm-2 . Using the finite element method, this model determines that the certain volume of cavity in the Ag@Cu2 O nanoreactors facilitates on-site CO retention and that multilayers of Cu species favor CO capture. Density functional theory calculations illustrate that the biased generation of ethanol products may arise from the (100)/(111) interface of the Cu layer. In-depth explorations in multilayer-bound nanoreactors provide structural and interfacial guidance for sequential coupling of CO2 RR intermediates for efficient C2+ generation.

7.
J Mater Chem B ; 11(11): 2431-2439, 2023 03 15.
Article in English | MEDLINE | ID: mdl-36810648

ABSTRACT

Fluorescence imaging has enabled much progress in biological fields, while the evolution of commercially available dyes has lagged behind their advanced applications. Herein, we launch triphenylamine-equipped 1,8-naphthaolactam (NP-TPA) as a versatile scaffold for the custom design of an efficient subcellular imaging agent (NP-TPA-Tar), given its bright and constant emissions in various states, significant Stokes shifts, and facile modifiability. The resultant four NP-TPA-Tars maintain excellent emission behavior with targeted modifications and can map the spatial distribution of lysosomes, mitochondria, endoplasmic reticulum, and plasma membrane in Hep G2 cells. Compared to its commercial counterpart, NP-TPA-Tar has a 2.8-25.2 fold increase in Stokes shift, a 1.2-1.9 fold increase in photostability, enhanced targeting capability, and comparable imaging efficiency even at low concentrations of 50 nM. This work will help to accelerate the update of current imaging agents and super-resolution and real-time imaging in biological applications.


Subject(s)
Mitochondria , Optical Imaging , Amines
8.
PLoS One ; 8(7): e67500, 2013.
Article in English | MEDLINE | ID: mdl-23874423

ABSTRACT

Next-generation sequencing (NGS) approaches are widely used in genome-wide genetic marker discovery and genotyping. However, current NGS approaches are not easy to apply to general outbred populations (human and some major farm animals) for SNP identification because of the high level of heterogeneity and phase ambiguity in the haplotype. Here, we reported a new method for SNP genotyping, called genotyping by genome reducing and sequencing (GGRS) to genotype outbred species. Through an improved procedure for library preparation and a marker discovery and genotyping pipeline, the GGRS approach can genotype outbred species cost-effectively and high-reproducibly. We also evaluated the efficiency and accuracy of our approach for high-density SNP discovery and genotyping in a large genome pig species (2.8 Gb), for which more than 70,000 single nucleotide polymorphisms (SNPs) can be identified for an expenditure of only $80 (USD)/sample.


Subject(s)
Genetic Markers/genetics , High-Throughput Nucleotide Sequencing/methods , Polymorphism, Single Nucleotide/genetics , Swine/genetics , Animals , Breeding/methods , Gene Library , Genotype , High-Throughput Nucleotide Sequencing/economics , Oligonucleotides/genetics
9.
Vet J ; 194(3): 423-4, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22627045

ABSTRACT

The aim of this study was to characterise the phenotypic and genotypic antibiotic resistance patterns of Streptococcus agalactiae isolated from cows with mastitis in China. Antibiotic resistance was based on minimum inhibitory concentrations and detection of resistance genes by PCR. S. agalactiae isolates most frequently exhibited phenotypic resistance to tetracycline, while the resistance genes most frequently detected were ermB, tetL and tetM. Resistance genes were detected in some susceptible isolates, whereas no resistance genes could be detected in some resistant isolates, indicating that the resistance genotype does not accurately predict phenotypic resistance.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Drug Resistance, Bacterial , Mastitis, Bovine/microbiology , Streptococcus agalactiae/drug effects , Streptococcus agalactiae/genetics , Amikacin/pharmacology , Animals , Bacterial Proteins/metabolism , Cattle , China , Erythromycin/pharmacology , Female , Genotype , Gentamicins/pharmacology , Microbial Sensitivity Tests/veterinary , Penicillin G/pharmacology , Phenotype , Streptococcus agalactiae/isolation & purification , Tetracycline/pharmacology
10.
Vet J ; 192(3): 550-2, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22001300

ABSTRACT

The molecular diversity, antibiotic resistance patterns and presence of resistance genes were determined in Staphylococcus aureus isolates from cases of bovine mastitis in a dairy cattle herd in China. Multiple locus variable number tandem repeat analysis was used for molecular typing. Resistance was determined through minimum inhibitory concentrations and resistance genes were detected by PCR. There was low molecular diversity; one predominant strain (type I) accounted for the majority of cases of S. aureus mastitis in the herd and this strain had a high frequency of resistance to penicillin and tetracycline. The most prevalent resistance genes were blaZ, ermC and tetM.


Subject(s)
Anti-Bacterial Agents/pharmacology , Mastitis, Bovine/microbiology , Staphylococcal Infections/veterinary , Staphylococcus aureus/drug effects , Animals , Cattle , China/epidemiology , Female , Gene Expression Regulation, Bacterial/physiology , Mastitis, Bovine/epidemiology , Microbial Sensitivity Tests , Nucleic Acid Amplification Techniques , Staphylococcal Infections/epidemiology , Staphylococcal Infections/microbiology , Staphylococcus aureus/genetics , Staphylococcus aureus/isolation & purification
11.
Acta Biol Hung ; 61(1): 52-63, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20194099

ABSTRACT

Objective of this study was to assess the quantification of osteocalcin (OCN) expression by ovine osteoblasts cultured with different concentrations of sodium fluoride (F) and sodium selenite (Se) to evaluate the interaction of these agents on OCN expression in vitro . We wanted to demonstrate a possible protective effect of selenium on the toxic effect of fluoride. Osteoblasts were isolated by complete trypsin and collagenase digestion from ovine calvarial bone and cultured in DMEM supplemented with 15% FBS at 37 degrees C in a humidified 5% CO 2 incubator. Identified osteoblasts were divided into one control group (C) and eight experimental groups, which were exposed to different concentrations of sodium fluoride (F; 0, 0.5, 1 mM) sodium selenite (Se; 0, 0.1, 1 microM). At different time points after treatment total RNA was extracted and reverse transcribed into first-strand cDNA. OCN mRNA was indirectly measured by real-time fluorescent quantitative PCR (qPCR). OCN mRNA expression in F 1 mM with Se 1 microM group was found to have a high peak at day seven and was lower before and afterwards. Expression of OCN mRNA in all groups except control could be promoted by F and/or Se showing a general upregulation. Furthermore, the toxicity from excessive exposure of osteoblast with F could be circumvented by usage of moderate concentration of Se. Osteoblasts cultured in vitro may have stressful responses to F and Se at the first few days. Low concentrations of Se inhibit the toxic effects of high concentrations of F. Therefore, F and Se could be used as antagonistic factors, which could regulate osteocalcin expression.


Subject(s)
Osteoblasts/drug effects , Osteoblasts/physiology , Osteocalcin , RNA, Messenger/metabolism , Sodium Fluoride/pharmacology , Sodium Selenite/pharmacology , Animals , Cell Shape , Cells, Cultured , Culture Media/chemistry , Gene Expression/drug effects , Nucleic Acid Denaturation , Osteoblasts/cytology , Osteocalcin/genetics , Osteocalcin/metabolism , RNA, Messenger/genetics , Sheep , Skull/cytology
12.
Yi Chuan ; 31(3): 285-9, 2009 Mar.
Article in Chinese | MEDLINE | ID: mdl-19273442

ABSTRACT

The polymorphism distributions of 14 microsatellite loci were detected using the Bovine Paternity PCR Typing Kit (including 11 X-STR) and 3 selected Y-STR microsatellite DNA markers. The genetic diversity were evaluated, and the feasibility of the application to individual identification and paternity testing were discussed. The results showed that all the 14 microsatellite loci had genetic polymorphisms in bulls, and the polymorphism information content (PIC) in loci MCM158 was the biggest (0.888), while the ETH10 was the lowest (0.482). Power of discrimination (DP) value of the 14 STR loci ranged from 0.715 to 0.968. The Cumulate DP (CDP) was 99.99%, and the Cumulate PE (CPE) also reached 99.99%. These results indicate that the 14 microsatellites can be applied to the individual identification.


Subject(s)
DNA Fingerprinting/methods , Microsatellite Repeats/genetics , Animals , Cattle , Chromosomes, Mammalian/genetics , Genetic Variation/genetics , Male , Polymerase Chain Reaction , Polymorphism, Genetic/genetics , Y Chromosome/genetics
13.
Endocrine ; 34(1-3): 101-7, 2008.
Article in English | MEDLINE | ID: mdl-18982462

ABSTRACT

We have analyzed a possible role of mitogen-activated protein kinase (MAPK) and activator protein-1 (AP-1) in the regulation of FSH-induced tissue type plasminogen activator (tPA) production in granulosa cells (GCs) prepared from DES-treated immature rats; Treatment of the cells in the presence of FSH with MAPK inhibitors, such as UO126 or SB203580, significantly decreased the FSH-induced tPA production, suggesting that multiple signaling pathways may be involved in FSH-regulated tPA expression. We further examined possible signaling action involved in FSH-activated ERK1/2 and p38 MAPK on tPA production, and observed that FSH receptor occupancy led to both ERK1/2 and p38 MAPK phosphorylation. Such action might be through a protein kinase A-dependent pathway because the observed activation was destroyed by the addition of its specific inhibitor H89 to the culture. The inhibition of ERK1/2 and p38 MAPK activation by their specific inhibitors remarkably reduced FSH-induced tPA mRNA and its protein production. We further examined whether AP-1 located in the tPA promoter is involved in FSH-regulated tPA production, and demonstrated that FSH significantly stimulated AP-1 expression, whereas inclusion of H89, UO126, or SB20358 in the culture significantly decreased FSH-induced AP-1 expression. In summary, FSH-induced ERK1/2 and p38 MAPK activation is capable of regulating tPA production in cultured primary GCs, and that the transcript factor AP-1 may be important in the regulation of FSH-induced tPA expression.


Subject(s)
Extracellular Signal-Regulated MAP Kinases/physiology , Follicle Stimulating Hormone/pharmacology , Response Elements , Tissue Plasminogen Activator/genetics , Transcription Factor AP-1/physiology , Animals , Cells, Cultured , Enzyme Activation/drug effects , Female , Gene Expression Regulation/drug effects , Granulosa Cells/drug effects , Granulosa Cells/metabolism , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 1/physiology , Mitogen-Activated Protein Kinase 3/metabolism , Mitogen-Activated Protein Kinase 3/physiology , Rats , Rats, Sprague-Dawley , Response Elements/drug effects , Response Elements/physiology , Time Factors , Tissue Plasminogen Activator/metabolism , Transcription Factor AP-1/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism , p38 Mitogen-Activated Protein Kinases/physiology
14.
Contraception ; 74(2): 157-64, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16860054

ABSTRACT

INTRODUCTION: Gonadotropin-releasing hormone (GnRH) II expression, specific high-affinity receptors for GnRH II and its potent bioactivity in human and baboon tissues led us to hypothesize that GnRH II is a bioactive peptide in primates. We recently demonstrated the contraceptive activity of GnRH II analog in rhesus monkeys. In the present experiment, we extended those studies to the dose-related action of this analog on parameters of luteal function and conception. METHODS: GnRH II analog (0-32 microg/day) or saline was administered via osmotic minipumps for 6 days (Days 1-6 postovulation) to regularly cycling rhesus monkeys mated with fertile males around the time of ovulation. Cycle dynamics was monitored through circulating luteinizing hormone, progesterone and estradiol. Pregnancy was determined by circulating chorionic gonadotropin concentrations. RESULTS: Progesterone production (Days 3-11) was significantly less (p<.05) for animals treated with 2, 4 or 8 microg/mL GnRH II analog than for controls, yet with higher doses of GnRH II analog (i.e., 16 or 32 microg/day), luteal progesterone was not different from that of saline-treated controls. The length of the luteal phase in all treated groups was similar to that of controls. In 18 animals mated at the time of ovulation and then treated with GnRH II analog (2-32 microg/day), no pregnancies resulted. In saline-treated controls, five of eight animals (62.5%) became pregnant. Thus, the contraceptive activity of this GnRH II analog did not correlate with luteal progesterone inhibition. CONCLUSIONS: These data demonstrate a dose-related action of GnRH II analog on luteal progesterone and establish the contraceptive activity of 2-32 microg/day GnRH II analog administered postovulation.


Subject(s)
Corpus Luteum/drug effects , Fertilization/drug effects , Gonadotropin-Releasing Hormone/analogs & derivatives , Animals , Contraceptive Agents, Female , Corpus Luteum/physiology , Dose-Response Relationship, Drug , Estradiol/blood , Female , Gonadotropin-Releasing Hormone/administration & dosage , Luteinizing Hormone/blood , Macaca mulatta , Male , Ovulation , Pregnancy , Progesterone/biosynthesis , Progesterone/blood
15.
J Endocrinol ; 186(1): 85-96, 2005 Jul.
Article in English | MEDLINE | ID: mdl-16002539

ABSTRACT

In the present study, we started out to test whether the follicle-stimulating hormone (FSH)-activated p38 MAPK signaling cascade was involved in the regulation of steroidogenesis in granulosa cells (GCs). GCs were prepared from the ovaries of DES-treated immature rats and cultured in serum-free medium. Treatment of GCs with FSH (50 ng/ml) induced the phosphorylation of p38 MAPK rapidly with the phosphorylation being observed within 5 min and reaching the highest level at 30 min. Such activation was protein kinase A-dependent as indicated by the results using specific inhibitors. FSH stimulated the production of progesterone and estradiol as well as the expression of the steroidogenic acute regulatory protein (StAR) in a time-dependent manner, with a maximum level being observed in the production of progesterone and StAR at 48 h. Moreover, the potent p38 MAPK inhibitor SB203580 (20 microM) augmented FSH-induced progesterone and StAR production, while reduced FSH-induced estradiol production at the same time (P<0.01). RT-PCR data showed that inclusion of SB203580 in the media enhanced FSH-stimulated StAR mRNA production, while decreased the FSH-stimulated P450arom mRNA expression (P<0.05). Immunocytochemical studies showed that FSH treatment together with the inhibition of p38 MAPK activity resulted in a higher expression of StAR in mitochondria than FSH treatment alone. FSH also significantly up-regulated the protein level of LRH-1, a member of the orphan receptor family that activates the expression of P450arom in ovaries and testes. p38 MAPK inactivation down-regulated the basal and FSH-induced LRH-1 expression significantly. The intra-cellular level of DAX-1, another orphan receptor that inhibits StAR expression, also decreased upon p38 MAPK being inactivated. For the first time, the present study suggests that FSH-activated p38 MAPK signal pathway regulates progesterone and estrogen production in GCs differentially, and that the transcription factors LRH-1 and DAX-1 might play important roles in the process.


Subject(s)
Estrogens/biosynthesis , Follicle Stimulating Hormone/pharmacology , Granulosa Cells/metabolism , MAP Kinase Signaling System/drug effects , p38 Mitogen-Activated Protein Kinases/metabolism , Animals , Aromatase/analysis , Aromatase/genetics , Cells, Cultured , Enzyme Activation , Estradiol/analysis , Estradiol/biosynthesis , Estrogens/genetics , Female , Granulosa Cells/drug effects , Immunohistochemistry/methods , Phosphoproteins/analysis , Phosphoproteins/genetics , Progesterone/analysis , Progesterone/biosynthesis , RNA/analysis , Radioimmunoassay/methods , Rats , Rats, Sprague-Dawley , Reverse Transcriptase Polymerase Chain Reaction
16.
Front Biosci ; 10: 1573-80, 2005 May 01.
Article in English | MEDLINE | ID: mdl-15769647

ABSTRACT

Stem cell factor (SCF) is essential for the development of primordial follicles. By using cultured ovaries from neonatal rats, the effect of SCF on early follicular development was investigated. Steroidogenesis is a hallmark of follicular development. Expressions of three key protein factors in steroidogenesis, SF-1, StAR, and P450arom, were investigated using immunohistochemistry and in situ hybridization. SF-1 and StAR proteins were expressed in all ovarian cells. P450arom mRNA was localized exclusively in oocytes implying that estrogen might be synthesized by oocytes at this stage. SCF up-regulated the mRNA and protein expression of these proteins, suggesting SCF might promote the production of estrogen during this period of time. To study the differentiation status of follicular cells, the expression of FSHR and its response to SCF treatment was examined by using semi-quantitative RT-PCR. The results showed that SCF inhibited the expression of FSHR mRNA. It was also observed that SCF stimulated the expression of basic fibroblast growth factor (bFGF) in oocytes. Inactivation of bFGF by its neutralizing antibody resulted in a reversal of the inhibitory effect of SCF on the expression of FSHR. Therefore, the FSHR inhibitory effect of SCF could be mediated by bFGF. In summary, it seems that, at the early stages of follicular development, SCF might stimulate oocytes to produce estrogen while it inhibits the differentiation of granulosa cells that are the major sources of estrogen at the late stages of follicular development.


Subject(s)
Gene Expression/drug effects , Ovarian Follicle/drug effects , Phosphoproteins/metabolism , Stem Cell Factor/pharmacology , Animals , Female , Fibroblast Growth Factor 2/physiology , Oocytes/drug effects , Oocytes/metabolism , Ovarian Follicle/growth & development , Ovarian Follicle/metabolism , Phosphoproteins/genetics , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley
17.
Mol Reprod Dev ; 70(1): 82-90, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15515061

ABSTRACT

Stem cell factor (SCF) is essential for the development of primordial follicles. One of its functions is to prevent oocytes from apoptosis. However, the underlying mechanism remains largely unknown. By using cultured ovaries that are rich in primordial follicles, the anti-apoptotic action of SCF and the potential signal transduction pathways were investigated. The apoptosis was evaluated by means of in situ 3'-end labeling. The expressions of proteins were analyzed with immunohistochemistry and Western blot. The data showed that SCF significantly prevented oocytes from apoptosis in the cultured organs. Addition of a specific pharmacological inhibitor of PI3K abolished the anti-apoptotic action of SCF while that of a MEK inhibitor did not. The phosphorylation of two mitogen activated protein kinases (MAPKs) (p42 and p44) and AKT, the respective substrates of MEK and PI3K, were enhanced by SCF treatment. Not surprisingly, the MAPK activation occurred only in theca cells. The expressions of apoptosis-related gene products, the Bcl-2 family proteins, in response to SCF treatment were also investigated. While SCF up-regulated the expression of the anti-apoptotic proteins Bcl-2 and Bcl-xL, it did the opposite to the pro-apoptotic factor Bax. The PI3K inhibitor reversed the regulation of SCF on Bcl-xL and Bax but not on Bcl-2. Therefore, it seemed that SCF initiated an anti-apoptotic signal starting from its membrane receptor c-kit to Bcl-2 family members through PI3K/AKT and other signaling cascades in the oocytes of primordial follicles.


Subject(s)
Apoptosis/drug effects , Oocytes/drug effects , Ovarian Follicle/drug effects , Signal Transduction , Stem Cell Factor/pharmacology , Animals , Apoptosis/physiology , Female , Intracellular Signaling Peptides and Proteins/pharmacology , Oocytes/chemistry , Organ Culture Techniques , Ovarian Follicle/chemistry , Phosphatidylinositol 3-Kinases/metabolism , Phosphatidylinositol 3-Kinases/physiology , Phosphoinositide-3 Kinase Inhibitors , Phosphorylation , Protein Serine-Threonine Kinases/analysis , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins c-bcl-2/analysis , Proto-Oncogene Proteins c-bcl-2/metabolism , Rats , Signal Transduction/drug effects , Signal Transduction/physiology , Stem Cell Factor/physiology
18.
Front Biosci ; 10: 896-904, 2005 Jan 01.
Article in English | MEDLINE | ID: mdl-15569628

ABSTRACT

Follicular development is characterized by both proliferation and differentiation of granulosa cells (GCs) under the control of FSH. However, the cellular mechanism by FSH is not known. Using cultured GCs, we examined whether FSH activated ERK1/2 was involved in the regulation of the proliferation related gene proliferating cell nuclear antigen (PCNA) and steroidogenesis. GCs were obtained from the ovaries of DES treated immature rats and cultured in serum free medium. The results showed that FSH activated ERK1/2 in a time dependent manner, with a peak at 20 min. Such activation was PKA dependent as was inhibited by specific inhibitors. FSH induced PCNA expression in a time dependent manner, with a maximum stimulation at 2 h. Similarly, StAR and steroid levels increased as FSH treatment time extended, with a maximum progesterone and StAR production at 48 h. ERK1/2 inactivation by UO126 inhibited the stimulatory effects of FSH on both PCNA and StAR expression and steroid synthesis in the GCs (p less than 0.01). Immunocytochemical studies further revealed that ERK1/2 inhibition led to a reduction of mitochondrial StAR in the GCs by FSH. These observations suggested that the stimulation of FSH on PCNA expression and steroidogenesis in GCs was mediated at least partially by ERK1/2.


Subject(s)
Granulosa Cells/metabolism , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Proliferating Cell Nuclear Antigen/metabolism , Animals , Butadienes/pharmacology , Enzyme Inhibitors/pharmacology , Female , Follicle Stimulating Hormone/metabolism , Immunohistochemistry , Nitriles/pharmacology , Phosphoproteins/metabolism , Rats , Rats, Sprague-Dawley , Time Factors
19.
J Clin Endocrinol Metab ; 89(9): 4513-20, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15356056

ABSTRACT

GnRH I (mammalian GnRH) was previously thought to be the only isoform of GnRH expressed in mammals, but GnRH II (chicken II GnRH) has now been identified in tissues of numerous mammalian species. Specific high-affinity receptors, which bind GnRH II and its analogs, have been identified throughout the reproductive tract, and GnRH II regulation of progesterone and human chorionic gonadotropin have been demonstrated. Thus, we hypothesized that GnRH II acts as a paracrine factor to regulate extrahypothalamic tissue functions and could be used as an effective contraceptive agent. In these studies, we examined the effect of a stable analog of GnRH II (GnRH II analog) on ovarian steroidogenesis, implantation, and maintenance of pregnancy in the rhesus monkey. GnRH II analog or saline was administered by osmotic minipumps on d 1-6, d 6-11, or d 11-17 to cycling monkeys mated with fertile males. Circulating progesterone and estradiol were determined during the luteal phase, and the cycle length before, during, and after treatment was observed. Circulating monkey chorionic gonadotropin was used to determine implantation. In animals treated with GnRH II analog on d 1-6, no pregnancies resulted; but in saline-treated controls, five of eight animals (62.5%) became pregnant. In animals treated with analog on d 6-11, two of five (40.0%); and on d 11-17, one of three (33.3%); implanted and normal pregnancies ensued. Cycle length or progesterone production was not affected by analog treatment. These data demonstrate that this GnRH II analog can act as a contraceptive agent when administered chronically around the time of ovulation or early luteal development. These findings suggest that GnRH II may play a role in reproductive physiology and that GnRH II analogs may serve as an effective, nonsteroidal, postcoital contraceptive.


Subject(s)
Contraceptive Agents/pharmacology , Gonadotropin-Releasing Hormone/analogs & derivatives , Gonadotropin-Releasing Hormone/pharmacology , Animals , Female , Macaca mulatta , Ovulation , Progesterone/blood
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