Name: ovarian tissue culture to visualize phenomena in mouse ovary
Uploaded: 2018-06-19T14:30:00
Description: Watch this Scientific Journal Video about Ovarian Tissue Culture to Visualize Phenomena in Mouse Ovary at JoVE.com

We thank Dr. Naojiro Minami (Kyoto University) for providing the Oog1pro3.9 mice. This research was supported by the JSPS (KAKENHI # JP15H06275) and the Nitto Foundation.

Mice were housed in an environmentally controlled room at 23 &#177;1 &#176;C with a 12 h light/12 h dark cycle. Animal care protocols and experiments were conducted in accordance with the Guidelines for Animal Experimentation at Aichi Medical University and were approved by the incumbent Animal Care and Use Committee.
1. Preparation of Culture Medium and Dishes
<ol>
	<li>To prepare basic culture medium, add fetal bovine serum (FBS, 5% v/v), FSH (100 mIU/mL), LH (10 mU/mL), and penicillin-str...

<ol>
	<li>Myers, M., Britt, K. L., Wreford, N. G., Ebling, F. J., Kerr, J. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Methods+for+quantifying+follicular+numbers+within+the+mouse+ovary.">Methods for quantifying follicular numbers within the mouse ovary.</a> Reproduction. 127 (5), 569-580 (2004).</li><li>Adams, G. P., Jaiswal, R., Singh, J., Malhi, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Progress+in+understanding+ovarian+follicular+dynamics+in+cattle.">Progress in understanding ovarian follicular dynamics in cattle.</a> Theriogenology. 69 (1), 72-80 (2008).</li><li>Palma, G. 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E., Skinner, M. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Growth+and+differentiation+factor-9+stimulates+progression+of+early+primary+but+not+primordial+rat+ovarian+follicle+development.">Growth and differentiation factor-9 stimulates progression of early primary but not primordial rat ovarian follicle development.</a> Biol Reprod. 67 (3), 1018-1024 (2002).</li><li>Nilsson, E. E., Kezele, P., Skinner, M. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Leukemia+inhibitory+factor+(LIF)+promotes+the+primordial+to+primary+follicle+transition+in+rat+ovaries.">Leukemia inhibitory factor (LIF) promotes the primordial to primary follicle transition in rat ovaries.</a> Mol Cell Endocrinol. 188 (1-2), 65-73 (2002).</li><li>Nilsson, E. E., Skinner, M. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bone+morphogenetic+protein-4+acts+as+an+ovarian+follicle+survival+factor+and+promotes+primordial+follicle+development.">Bone morphogenetic protein-4 acts as an ovarian follicle survival factor and promotes primordial follicle development.</a> Biol Reprod. 69 (4), 1265-1272 (2003).</li><li>Nilsson, E. E., Skinner, M. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kit+ligand+and+basic+fibroblast+growth+factor+interactions+in+the+induction+of+ovarian+primordial+to+primary+follicle+transition.">Kit ligand and basic fibroblast growth factor interactions in the induction of ovarian primordial to primary follicle transition.</a> Mol Cell Endocrinol. 214 (1-2), 19-25 (2004).</li><li>Abe, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Establishment+of+conditional+reporter+mouse+lines+at+ROSA26+locus+for+live+cell+imaging.">Establishment of conditional reporter mouse lines at ROSA26 locus for live cell imaging.</a> Genesis. 49 (7), 579-590 (2011).</li><li>Lan, Z. J., Xu, X., Cooney, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+oocyte-specific+expression+of+Cre+recombinase+activity+in+GDF-9-iCre,+Zp3cre,+and+Msx2Cre+transgenic+mice.">Differential oocyte-specific expression of Cre recombinase activity in GDF-9-iCre, Zp3cre, and Msx2Cre transgenic mice.</a> Biol Reprod. 71 (5), 1469-1474 (2004).</li><li>Payer, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Generation+of+stella-GFP+transgenic+mice:+a+novel+tool+to+study+germ+cell+development.">Generation of stella-GFP transgenic mice: a novel tool to study germ cell development.</a> Genesis. 44 (2), 75-83 (2006).</li><li>Ohinata, Y., Sano, M., Shigeta, M., Yamanaka, K., Saitou, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+comprehensive,+non-invasive+visualization+of+primordial+germ+cell+development+in+mice+by+the+Prdm1-mVenus+and+Dppa3-ECFP+double+transgenic+reporter.">A comprehensive, non-invasive visualization of primordial germ cell development in mice by the Prdm1-mVenus and Dppa3-ECFP double transgenic reporter.</a> Reproduction. 136 (4), 503-514 (2008).</li></ol>

In this study, we developed two new methods for studying follicle development in mouse ovaries. The first method involves culture of sliced ovarian adult mice tissues followed by analyses of follicle development, and the second involves the use of time-lapse imaging to visualize early follicle development during the gonadotropin-independent stage. Previously, we used the present ovary tissue culture method to assess the effect of leukemia inhibitory factor and progesterone on follicle development8...

Female mouse ovaries contain several thousand follicles1, and periodic ovulation matures approximately ten oocytes at each estrus cycle. Follicles are classified into several developmental stages: primordial, primary, secondary, antral, and Graafian follicles, depending on the form of the granulosa cellular layer surrounding each oocyte. Most primordial follicles are dormant, and some of them are activated and grow into primary follicles at each estrus cycle2. After the secondary follicular stage, follicle development is mainly regulated by gonadotropins, follicular stimulating hormone (FSH), and luteinizing hormone (LH). However, primordial and primary follicle development is independent of gonadotropin, and the regulatory mechanisms that govern these stages remain poorly inderstood3,4,5. In addition to growth factors and hormones, the primordial and primary follicle is regulated by the interactions among follicles6,7. Therefore, we performed analyses of follicle dynamics in mouse ovary tissues, and investigated the associated regulatory mechanisms using ovarian tissue cultures8,9,10.
Herein, we introduce two ovarian tissue culture model methods. The first is used to analyze follicle development by measurement of follicular areas, and the second is used to study the regulatory mechanism during early follicle development from primordial to secondary follicle stage with transgenic mice. For follicle development analysis, we mainly used ovaries of 4-week old female mice because they allow for easy visualization of follicles. To induce periodical ovulation and model in vivo follicle development, we reproduced LH surge and observed ovulation, follicle atresia, and secretion of estradiol under tissue culture conditions. Images of the cultured ovaries were captured, and the follicle development processes were analyzed by tracing changes in the follicular area. However, in bright field microscopy analyses, the distinction between primordial and early primary follicles was unclear. Thus, we developed a method to detect small follicles, and distinguish between the primordial, primary, and secondary follicle in cultured ovarian tissues using Oogenesin1 (Oog1) pro3.9 and R26-H2B-mCherry transgenic mice ovaries at days 0 and 4 after birth11. Oog1 expression is detectable in oocytes after entry into meiosis, and gradually increases with follicle development, allowing observation of the transition from primordial to primary follicles using time-lapse images of cultured ovary tissue11,12. Although morphological methods have been used to study factors that activate dormant primordial follicles13,14,15,16, physiological follicle development in ovaries is difficult to observe, and the effects of various factors remain uncharacterized. The present culture methods were designed to address this paucity in real time analyses of target factors.
In the present study, we tracked follicular development using a time-lapse imaging method and characterized the process of follicle development. Our novel methods offer an unprecedented tool for investigating the physiology of ovaries.

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			<td height="21" style="height:21px;width:383px;">Follicle stimulating hormone from human pituitary</td>
			<td style="width:224px;">SIGMA</td>
			<td style="width:119px;">F4021</td>
			<td style="width:451px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Lutenizing hormone from equine pituitary</td>
			<td>SIGMA</td>
			<td>L9773</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Penicillin-streptomycin solution</td>
			<td>Wako Pure Chemical Industries</td>
			<td>168-23191</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">MEM a, GlutaMax, no nucleotides</td>
			<td>Thermo Fisher</td>
			<td>32561037</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Glass bottom dish</td>
			<td>MatTek</td>
			<td>P35G-0-10-C</td>
			<td>35mm dish, No. 0 coverslip, 10mm glass diameter</td>
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			<td height="21" style="height:21px;">Millicell cell culture insert</td>
			<td>Merck Millipore</td>
			<td>PICM0RG50</td>
			<td>Diameter: 315 mm, pore size: 0.4 mm, material: hydrophilic PTTE</td>
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			<td height="21" style="height:21px;width:383px;">3.5cm cell culture dishes</td>
			<td style="width:224px;">greiner bio-one</td>
			<td style="width:119px;">627160</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;width:383px;">50ml / centrifuge tube with triple seal cap</td>
			<td style="width:224px;">IWAKI</td>
			<td style="width:119px;">2345-050</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:383px;">Low-profile disposable blades 819</td>
			<td style="width:224px;">Leica</td>
			<td style="width:119px;">14035838925</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">LSM 710</td>
			<td>Carl Zeiss</td>
			<td style="width:119px;"></td>
			<td>Confocal microscope</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">CellVoyager, CV1000</td>
			<td>Yokogawa Electric Corporation</td>
			<td style="width:119px;"></td>
			<td>Time-lapse imaging</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">BZ-X700</td>
			<td>KEYENCE</td>
			<td style="width:119px;"></td>
			<td>Time-lapse imaging</td>
		</tr>
	</tbody>
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ovarian tissue culture to visualize phenomena in mouse ovary

Mammalian females periodically ovulate an almost constant number of oocytes during each estrus cycle. To sustain such regularity and periodicity, regulation occurs at the hypothalamic-pituitary-gonadal axis level and on developing follicles in the ovary. Despite active studies, follicle development mechanisms are not clear because of the several steps involved from the dormant primordial follicle activation to ovulation, and because of the regulation complexity that differs at each follicular stage. To investigate the mechanisms of follicle development, and the dynamics of follicles throughout the estrus cycle, we developed a mouse ovarian tissue culture model that can be used to observe follicle development using a microscope. Systematic follicle development, periodical ovulation, and follicle atresia can all be reproduced in the cultured ovary model, and the culture conditions can be experimentally modulated. Here, we demonstrate the usefulness of this method in the study of the regulatory mechanisms of follicle development and other ovarian phenomena.

Figure 1&#160;shows the protocol for changes in media during ovarian tissue culture. Following this program, 4-week-old ICR mice ovaries were cultured and imaged at 24-h intervals using confocal microscopy (Figure 2). During culture of ovary tissues for 3 weeks, most antral and secondary follicles were degenerated by follicle atresia and some were ovulated (Figure 2D and Tabl...

Watch this Scientific Journal Video about Ovarian Tissue Culture to Visualize Phenomena in Mouse Ovary at JoVE.com

Ovarian Tissue Culture to Visualize Phenomena in Mouse Ovary

Ovarian tissue cultures can be used as models of follicle development, ovulation, and follicle atresia and indicate regulatory mechanisms of dynamic ovarian processes.

Mammalian females periodically ovulate an almost constant number of oocytes during each estrus cycle. To sustain such regularity and periodicity, ...

This method can help answer key questions in the ovary research field about follicle development, follicle atresia and operation. The main advantage of this technique is that we can reproduce the ovarian phenomena under controlled culture conditions for the observation in real time. To prepare the ovaries from a four week old Institute of Cancer Research mouse for culture:Use scissors and tweezers to trim the surrounding tissue from the ovaries under a stereo microscope, and place the cleaned ovaries into a dish of fresh culture medium.When all of the ovaries have been trimmed, transfer the individual ovaries onto a piece of filter paper moistened with 37 degrees Celsius PBS, and use a microtome blade to slice each ovary into four pieces. Transfer the slices into a 3.5 centimeter dish of 37 degrees Celsius culture medium, and use a micropipette to add an about 0.5 micrometer droplet of culture medium onto one cell culture insert per ovarian tissue section. In a second 3.5 centimeter glass bottom cell culture dish containing one millimeter of medium:Using tweezers, transfer one tissue specimen into each droplet and place the plate in a cell culture incubator.Replace the supernatant in the dish with fresh 37 degrees Celsius culture medium every two days and treat the ovaries with 100 milliunits per milliliter of FSH and LH for 12 hours every fourth day. Begin imaging the cultured ovaries every 24 hours after one day of culture to allow sufficient follicle growth between imaging sessions;capturing images at 30 minute intervals using a time-lapse imaging system under the appropriate experimental conditions. To analyze ovarian follicle development:Open the images in ImageJ and open the analyze menu to select set scale.Enter the side lengths of the captured images and the corresponding numbers of pixels in the known distance and distance in pixels fields, respectively. Then, use the free-hand tool to outline the follicles and click measure. During a three week ovarian tissue slice culture period, most antral and secondary follicles are degenerated by follicle atresia, and some are ovulated.Some follicles develop in groups during each LH surge cycle. While the timing of ovulation and the number of ovulated oocytes differs between mouse ovaries, ovulation from cultured ovaries predominantly occurs within 48 hours of each LH surge. Note that not all ovulated oocytes release first polar bodies after ovulation.Primordial and primary follicles are present simultaneously in postnatal day four mouse ovaries. Whereas, only primordial follicles are present in postnatal day zero ovaries. However, primary follicles become detectable in cultured postnatal day zero ovaries after 30 to 40 hours of culture as demonstrated.Primordial and primary follicles can also be distinguished in the cultured ovaries isolated from mCherry transgenic animals by the mCherry positive nuclei of granulosa cells;allowing the tracking of the follicle stages in the ovary slice cultures. I hope that this technique paves the way for researchers in the field of reproductive technology to explore new techniques for fertility treatment.

ovarian-tissue-culture-to-visualize-phenomena-in-mouse-ovary

Research

JoVE Journal

Developmental Biology

Culture and Co-Culture of Mouse Ovaries and Ovarian Follicles

The mammalian ovary is composed of ovarian follicles, each follicle consisting of a single oocyte surrounded by somatic granulosa cells, enclosed together within a basement membrane. A finite pool of follicles is laid down during embryonic development, when oocytes in meiotic arrest form a close association with flattened granulosa cells, forming primordial follicles. By or shortly after birth, mammalian ovaries contain their lifetime&#8217;s supply of primordial follicles, from which point onwards there is a steady release of follicles into the growing follicular pool.
The ovary is particularly amenable to development in vitro, with follicles growing in a highly physiological manner in culture. This work describes the culture of whole neonatal ovaries containing primordial follicles, and the culture of individual ovarian follicles, a method which can support the development of follicles from an immature through to the preovulatory stage, after which their oocytes are able to undergo fertilization in vitro. The work outlined here uses culture systems to determine how the ovary is affected by exposure to external compounds. We also describe a co-culture system, which allows investigation of the interactions that occur between growing follicles and the non-growing pool of primordial follicles.

This protocol describes the primary culture/co-culture of mouse ovarian tissue, using ovaries from neonatal mice and individual ovarian follicles from prepubertal mice. The culture techniques support development in a highly physiological manner, allowing investigation of the effect of extrinsic agents on the ovary, and of interactions between ovarian follicles.

The mammalian ovary is composed of ovarian follicles, each follicle consisting of a single oocyte surrounded by somatic granulosa cells, enclosed together ...

Ex Utero Electroporation and Organotypic Slice Culture of Mouse Hippocampal Tissue

Mouse genetics offers a powerful tool determining the role of specific genes during development. Analyzing the resulting phenotypes by immunohistochemical and molecular methods provides information of potential target genes and signaling pathways. To further elucidate specific regulatory mechanisms requires a system allowing the manipulation of only a small number of cells of a specific tissue by either overexpression, ablation or re-introduction of specific genes and follow their fate during development. To achieve this ex utero electroporation of hippocampal structures, especially the dentate gyrus, followed by organotypic slice culture provides such a tool. Using this system to generate mosaic deletions allows determining whether the gene of interest regulates cell-autonomously developmental processes like progenitor cell proliferation or neuronal differentiation. Furthermore it facilitates the rescue of phenotypes by re-introducing the deleted gene or its target genes. In contrast to in utero electroporation the ex utero approach improves the rate of successfully targeting deeper layers of the brain like the dentate gyrus. Overall ex utero electroporation and organotypic slice culture provide a potent tool to study regulatory mechanisms in a semi-native environment mirroring endogenous conditions.

Ex Utero Electroporation and Organotypic Slice Culture of Mouse Hippocampal Tissue

Here we present a protocol providing a tool to examine regulatory mechanisms of specific genes during hippocampal development. Employing ex utero electroporation and organotypic slice culture allows the up- and down-regulation of the expression of genes of interest in single cells and follow their fate during development.

Mouse genetics offers a powerful tool determining the role of specific genes during development. Analyzing the resulting phenotypes by immunohistochemical ...

Loss- and Gain-of-function Approach to Investigate Early Cell Fate Determinants in Preimplantation Mouse Embryos

Gene silencing and overexpression techniques are instrumental for the identification of genes involved in embryonic development. Direct target gene modification in preimplantation embryos provides a means to study the underlying mechanisms of genes implicated in, for instance, cellular differentiation into the trophectoderm (TE) and the inner cell mass (ICM). Here, we describe a protocol that examines the role of neogenin as an authentic receptor for initial cell fate determination in preimplantation mouse embryos. First, we discuss the experimental manipulations that were used to produce gain and loss of neogenin function by microinjecting neogenin cDNA and shRNA; the effectiveness of this approach was confirmed by a strong correlation between the pair-wise expression levels of either red fluorescent protein (RFP) or green fluorescent protein (GFP) and the immunocytochemical quantification of neogenin expression. Secondly, overexpression of neogenin in preimplantation mouse embryos leads to normal ICM development while neogenin knockdown causes the ICM to develop abnormally, implying that neogenin could be a receptor that relays extracellular cues to drive blastomeres to early cell fates. Given the success of this detailed protocol in investigating the function of a novel embryonic developmental stage-specific receptor, we propose that it has the potential to aid in exploration and identification of other stage-specific genes during embryogenesis.

The goal of this protocol is to describe a loss- and gain-of function method that is applicable to identify neogenin as a stage-specific receptor that leads to trophectoderm and inner cell mass differentiation in preimplantation mouse embryos.

 Gene silencing and overexpression techniques are instrumental for the identification of genes involved in embryonic development. Direct target gene ...

A Novel Mammary Fat Pad Transplantation Technique to Visualize the Vessel Generation of Vascular Endothelial Stem Cells

Endothelial cells (ECs) are the fundamental building blocks of the vascular architecture and mediate vascular growth and remodeling to ensure proper vessel development and homeostasis. However, studies on endothelial lineage hierarchy remain elusive due to the lack of tools to gain access as well as to directly evaluate their behavior in vivo. To address this shortcoming, a new tissue model to study angiogenesis using the mammary fat pad has been developed. The mammary gland develops mostly in the postnatal stages, including puberty and pregnancy, during which robust epithelium proliferation is accompanied by extensive vascular remodeling. Mammary fat pads provide space, matrix, and rich angiogenic stimuli from the growing mammary epithelium. Furthermore, mammary fat pads are located outside the peritoneal cavity, making them an easily accessible grafting site for assessing the angiogenic potential of exogenous cells. This work also describes an efficient tracing approach using fluorescent reporter mice to specifically label the targeted population of vascular endothelial stem cells (VESCs) in vivo. This lineage tracing method, coupled with subsequent tissue whole-mount microscopy, enable the direct visualization of targeted cells and their descendants, through which the proliferation capability can be quantified and the differentiation commitment can be fate-mapped. Using these methods, a population of bipotent protein C receptor (Procr) expressing VESCs has recently been identified in multiple vascular systems. Procr+ VESCs, giving rise to both new ECs and pericytes, actively contribute to angiogenesis during development, homeostasis, and injury repair. Overall, this manuscript describes a new mammary fat pad transplantation and in vivo lineage tracing techniques that can be used to evaluate the stem cell properties of VESCs.

This work demonstrates a novel approach to assess the proliferation, differentiation, and vessel-forming potential of vascular endothelial stem cells (VESCs) through mammary fat pad transplantation followed by whole-mount tissue preparation for microscopic observation. A lineage tracing strategy to investigate the behavior of VESCs in vivo is also presented.

Endothelial cells (ECs) are the fundamental building blocks of the vascular architecture and mediate vascular growth and remodeling to ensure proper ...

Live Imaging of Mouse Secondary Palate Fusion

The fusion of the secondary palatal shelves to form the intact secondary palate is a key process in mammalian development and its disruption can lead to cleft secondary palate, a common congenital anomaly in humans. Secondary palate fusion has been extensively studied leading to several proposed cellular mechanisms that may mediate this process. However, these studies have been mostly performed on fixed embryonic tissues at progressive timepoints during development or in fixed explant cultures analyzed at static timepoints. Static analysis is limited for the analysis of dynamic morphogenetic processes such a palate fusion and what types of dynamic cellular behaviors mediate palatal fusion is incompletely understood. Here we describe a protocol for live imaging of ex vivo secondary palate fusion in mouse embryos. To examine cellular behaviors of palate fusion, epithelial-specific Keratin14-cre was used to label palate epithelial cells in ROSA26-mTmGflox reporter embryos. To visualize filamentous actin, Lifeact-mRFPruby reporter mice were used. Live imaging of secondary palate fusion was performed by dissecting recently-adhered secondary palatal shelves of embryonic day (E) 14.5 stage embryos and culturing in agarose-containing media on a glass bottom dish to enable imaging with an inverted confocal microscope. Using this method, we have detected a variety of novel cellular behaviors during secondary palate fusion. An appreciation of how distinct cell behaviors are coordinated in space and time greatly contributes to our understanding of this dynamic morphogenetic process. This protocol can be applied to mutant mouse lines, or cultures treated with pharmacological inhibitors to further advance understanding of how secondary palate fusion is controlled.

Here, we present a protocol for live imaging of mouse secondary palate fusion using confocal microscopy. This protocol can be used in combination with a variety of fluorescent reporter mouse lines, and with pathway inhibitors for mechanistic insight. This protocol can be adapted for live imaging in other developmental systems.

The fusion of the secondary palatal shelves to form the intact secondary palate is a key process in mammalian development and its disruption can lead to ...

Methods for Imaging Intracellular pH of the Follicle Stem Cell Lineage in Live Drosophila Ovarian Tissue

Changes in intracellular pH (pHi) play important roles in the regulation of many cellular functions, including metabolism, proliferation, and differentiation. Typically, pHi dynamics are determined in cultured cells, which are amenable to measuring and experimentally manipulating pHi. However, the recent development of new tools and methodologies has made it possible to study pHi dynamics within intact, live tissue. For Drosophila research, one important development was the generation of a transgenic line carrying a pHi biosensor, mCherry::pHluorin. Here, we describe a protocol that we routinely use for imaging live Drosophila ovarioles to measure pHi in the epithelial follicle stem cell (FSC) lineage in mCherry::pHluorin transgenic wild type lines; however, the methods described here can be easily adapted for other tissues, including the wing discs and eye epithelium. We describe techniques for expressing mCherry::pHluorin in the FSC lineage, maintaining ovarian tissue during live imaging, and acquiring and analyzing images to obtain pHi values.

Methods for Imaging Intracellular pH of the Follicle Stem Cell Lineage in Live Drosophila Ovarian Tissue

We provide a protocol for imaging intracellular pH of an epithelial stem cell lineage in live Drosophila ovarian tissue. We describe methods to generate transgenic flies expressing a pH biosensor, mCherry::pHluorin, image the biosensor using quantitative fluorescence imaging, generate standard curves, and convert fluorescence intensity values to pH values.

Changes in intracellular pH (pHi) play important roles in the regulation of many cellular functions, including metabolism, proliferation, and ...

Orthotopic Ovarian Transplantation Procedures to Investigate the Life- and Health-span Influence of Ovarian Senescence in Female Mice

Ovarian transplantation was first conducted at Utah State University in 1963. In more recent work, heterochronic transplantation of mammalian ovaries is being used to investigate the health-protective effects of young ovaries in young females. The current procedures employ an orthotopic transplantation method, where allogenic ovaries are transplanted back to their original position in the ovarian bursa. This is in contrast to the more commonly used heterotopic transplantation of ovaries/ovarian tissue subcutaneously or under the kidney capsule. All three locations provide efficient revascularization of the transplanted tissues. However, orthotopic transplantation provides the ovary with the most natural signaling environment and is the only procedure that provides the opportunity for the animal to reproduce naturally post-operatively. One must take care to remove all endogenous ovarian tissue during the ovariectomy procedure. If any endogenous tissue remains or if only one ovary is removed, the transplanted tissue will remain dormant until the existing tissue becomes senescent. While revascularization of the transplanted ovaries occurs very quickly, the transplant recipient can take a considerable amount of time to adapt to a new hypothalamic/pituitary/gonadal/adrenal (HPG/A) axis signaling regime associated with the transplanted tissue. This normally takes about 100 days in the mouse. Therefore, transplantation experiments should be designed to accommodate this adaptation period. Typical results with ovarian transplantation will include changes in the health of the recipient that reflect the age of the transplanted ovary, rather than the chronological age of the recipient.

Described here are orthotopic ovarian transplantation protocols for modifying ovarian influence on the physiology of the recipient mouse. This surgical procedure is used to expose female mice to various types of ovarian influence and may include heterochronic transplantations and transplantation of ovaries that have undergone various ex vivo treatments.

Ovarian transplantation was first conducted at Utah State University in 1963. In more recent work, heterochronic transplantation of mammalian ovaries is ...

A Hyperandrogenic Mouse Model to Study Polycystic Ovary Syndrome

Hyperandrogenemia plays a critical role in reproductive and metabolic function in females and is the hallmark of polycystic ovary syndrome. Developing a lean PCOS-like mouse model that mimics women with PCOS is clinically meaningful. In this protocol, we describe such a model. By inserting a 4 mm length of DHT (dihydrotestosterone) crystal powder pellet (total length of pellet is 8 mm), and replacing it monthly, we are able to produce a PCOS-like mouse model with serum DHT levels 2 fold higher than mice not implanted with DHT (no-DHT). We observed reproductive and metabolic dysfunction without changing body weight and body composition. While exhibiting a high degree of infertility, a small subset of these PCOS-like female mice can get pregnant and their offspring show delayed puberty and increased testosterone as adults. This PCOS-like lean mouse model is a useful tool to study the pathophysiology of PCOS and the offspring from these PCOS-like dams.

We describe the development of a lean PCOS-like mouse model with&#160;dihydrotestosterone pellet to study the pathophysiology of PCOS and the offspring from these PCOS-like dams.

Hyperandrogenemia plays a critical role in reproductive and metabolic function in females and is the hallmark of polycystic ovary syndrome. Developing a ...

Assessment of Oxidative Damage in the Primary Mouse Ocular Surface Cells/Stem Cells in Response to Ultraviolet-C (UV-C) Damage

The ocular surface is subjected to regular wear and tear due to various environmental factors. Exposure to UV-C radiation constitutes an occupational health hazard. Here, we demonstrate the exposure of primary stem cells from the mouse ocular surface to UV-C radiation. Reactive oxygen species (ROS) formation is the readout of the extent of oxidative stress/damage. In an experimental in vitro setting, it is also essential to assess the percentage of dead cells generated due to oxidative stress. In this article, we will demonstrate the 2&#39;,7&#39;-Dichlorofluoresceindiacetate (DCFDA) staining of UV-C exposed mouse primary ocular surface stem cells and their quantification based on the fluorescent images of DCFDA staining. DCFDA staining directly corresponds to ROS generation. We also demonstrate the quantification of dead and live cells by simultaneous staining with propidium iodide (PI) and Hoechst 3332 respectively and the percentage of DCFDA (ROS positive) and PI positive cells.

Assessment of Oxidative Damage in the Primary Mouse Ocular Surface Cells/Stem Cells in Response to Ultraviolet-C UV-C Damage

This protocol demonstrates the simultaneous detection of reactive oxygen species (ROS), live cells, and dead cells in live primary cultures from mouse ocular surface cells. 2&#39;,7&#39;-Dichlorofluoresceindiacetate, propidium iodide, and Hoechst staining are used to assess the ROS, dead cells, and live cells, respectively, followed by imaging and analysis.

The ocular surface is subjected to regular wear and tear due to various environmental factors. Exposure to UV-C radiation constitutes an occupational ...

Isolation, Culture, and Adipogenic Induction of Neural Crest Original Adipose-Derived Stem Cells from Periaortic Adipose Tissue

An excessive amount of adipose tissue surrounding the blood vessels (perivascular adipose tissue, also known as PVAT) is associated with a high risk of cardiovascular disease. ADSCs derived from different adipose tissues show distinct features, and those from the PVAT have not been well characterized. In a recent study, we reported that some ADSCs in the periaortic arch adipose tissue (PAAT) descend from the neural crest cells (NCCs), a transient population of migratory cells originating from the ectoderm.
In this paper, we describe a protocol for isolating red fluorescent protein (RFP)-labeled NCCs from the PAAT of Wnt-1 Cre+/-;Rosa26RFP/+ mice and inducing their adipogenic differentiation in vitro. Briefly, the stromal vascular fraction (SVF) is enzymatically dissociated from the PAAT, and the RFP+ neural crest derived ADSCs (NCADSCs) are isolated by fluorescence activated cell sorting (FACS). The NCADSCs differentiate into both brown and white adipocytes, can be cryopreserved, and retain their adipogenic potential for ~3&#8211;5 passages. Our protocol can generate abundant ADSCs from the PVAT for modeling PVAT adipogenesis or lipogenesis in vitro. Thus, these NCADSCs can provide a valuable system for studying the molecular switches involved in PVAT differentiation.

We present a protocol for the isolation, culture, and adipogenic induction of neural crest derived adipose-derived stem cells (NCADSCs) from the periaortic adipose tissue of Wnt-1 Cre+/-;Rosa26RFP/+ mice. The NCADSCs can be an easily accessible source of ADSCs for modeling adipogenesis or lipogenesis in vitro.

An excessive amount of adipose tissue surrounding the blood vessels (perivascular adipose tissue, also known as PVAT) is associated with a high risk of ...