Publications by authors named "Beate Braun"

The study aimed to establish a long-term 3D cell culture model using luteinized follicular cells to investigate the functionality and life cycle of the CL in felids. A mixture of cell types from antral follicles was luteinized in vitro and cultured for up to 23 days. The method, initially applied to the domestic cat, was later extended to Persian and Clouded leopards.

View Article and Find Full Text PDF

The spermadhesin AQN-3 is a major component of porcine seminal plasma. While various studies suggest that this protein binds to boar sperm cells, its attachment to the cells is poorly understood. Therefore, the capacity of AQN-3 to interact with lipids was investigated.

View Article and Find Full Text PDF

In the present study, granulosa cells (GCs) from domestic cats and Persian leopard were cultured and characterized from selected days. The culture period was divided into two phases: maintenance, which lasted for 7 days, and luteinization, which followed for up to 11 days. Luteinization was performed on ultra-low attachment plates, supporting the formation of spheroids in a medium supplemented with insulin, forskolin, and luteinizing hormone (LH).

View Article and Find Full Text PDF

Like humans, many felid species suffer from teratozoospermia and frequently produce low numbers of normal spermatozoa. Male fertility can be affected by oxidative and dicarbonyl stress. Because of the high level of glycolytic activity in testes, reactive dicarbonyl metabolites may arise as side-products of glycolysis; their generation is further promoted by oxidative stress.

View Article and Find Full Text PDF

As a major spermadhesin first found in the seminal plasma (SP) of boars, AWN is described to fulfil a variety of reproduction related tasks. Although being the best investigated boar spermadhesin, information about its interaction with membranes is inconsistent. In this regard, previous reports locate AWN either inside or on the surface of sperm cells and at different regions, depending on the method and antibody used.

View Article and Find Full Text PDF

In the present study, we investigated the effect of the synthetic analog of prostaglandin F2α (PGF2α)-cloprostenol-on cultured steroidogenic luteal cells of selected felid species over a 2-day culture period. The changes induced by cloprostenol were measured based on progesterone concentration and mRNA expression analysis of selected genes. Cloprostenol significantly reduced concentration of progesterone in cell culture medium of small luteal cells isolated from domestic cat corpora lutea (CL) at the development/maintenance stage (P < 0.

View Article and Find Full Text PDF

In vitro growth (IVG) of dormant primordial ovarian follicles aims to produce mature competent oocytes for assisted reproduction. Success is dependent on optimal in vitro conditions complemented with an understanding of oocyte and ovarian follicle development in vivo. Complete IVG has not been achieved in any other mammalian species besides mice.

View Article and Find Full Text PDF

The objective of this study was to investigate the effect of luteinizing hormone (LH) on steroidogenic luteal cells obtained from corpora lutea (CL) of the domestic cat and selected wild felids. Luteal cells were isolated enzymatically from CL at different developmental stages and cultured for two days in the presence and absence of 100 ng/mL LH, respectively. Functionality was assessed by progesterone (P4) accumulation in cell culture media determined by ELISA.

View Article and Find Full Text PDF

Emerging fungal diseases have become challenges for wildlife health and conservation. North American hibernating bat species are threatened by the psychrophilic fungus Pseudogymnoascus destructans (Pd) causing the disease called white-nose syndrome (WNS) with unprecedented mortality rates. The fungus is widespread in North America and Europe, however, disease is not manifested in European bats.

View Article and Find Full Text PDF

The current study aimed to isolate, culture and characterize small (SLC) and large (LLC) steroidogenic cells from the (CL) of non-pregnant domestic cats. Isolation of feline SLC was based on an enzymatic digestion of luteal tissue, whereas LLC were obtained by mechanical disruption of CL. To assess function of both cell types, progesterone secretion and mRNA expression of selected genes involved in steroid and prostaglandin synthesis were measured, as well as relative transcript abundance of hormone receptors and anti-oxidative enzymes, before and during culture.

View Article and Find Full Text PDF

Video gaming is an extremely popular leisure-time activity with more than two billion users worldwide (Newzoo, 2017). However, the media as well as professionals have underscored the potential dangers of excessive video gaming. With the present research, we aimed to shed light on the relation between video gaming and gamers' psychological functioning.

View Article and Find Full Text PDF

A number of viruses causing sexually transmissible diseases are transmitted via mammalian seminal plasma. Several components of seminal plasma have been shown to influence those viruses and their physiological impact. To unravel whether components of seminal plasma could affect viruses transmitted via other pathways, it was investigated here whether the bovine seminal plasma protein PDC-109, belonging to the Fn-type 2 protein family, influences the activity of influenza A viruses, used as a model for enveloped viruses.

View Article and Find Full Text PDF

In the present study we comprehensively characterize intratesticular sex steroid production, metabolism and receptors in the domestic cat to elucidate the role of testosterone, estradiol and progesterone in testis development, steroid synthesis and spermatogenesis. There is a great demand for new concepts of fertility control in domestic (feral) cats and wild felids. The acquired knowledge will help to understand the regulation of spermatogenesis in felids, and may reveal new target points for male contraception.

View Article and Find Full Text PDF
Article Synopsis
  • The corpus luteum (CL) in Iberian and Eurasian lynx can last over 2 years and continues to produce progesterone, unlike in other studied species.
  • Researchers measured various hormone receptors in both lynx and domestic cat CL to understand potential mechanisms behind this prolonged persistence.
  • Findings suggest that high levels of specific hormone receptors in the lynx's persistent CL may indicate that sex steroids play a role in maintaining the CL's function and longevity.
View Article and Find Full Text PDF

Felids show different reproductive strategies related to the luteal phase. Domestic cats exhibit a seasonal polyoestrus and ovulation is followed by formation of corpora lutea (CL). Pregnant and non-pregnant cycles are reflected by diverging plasma progesterone (P4) profiles.

View Article and Find Full Text PDF

The corpus luteum (CL) is a transient gland formed in the ovary after ovulation and is the major source of progesterone. In the Iberian and Eurasian lynx, CL physiologically persist after parturition and retain their capacity to produce progesterone, thus suppressing the ovarian activity. This unique reproductive characteristic has a big impact on the success of assisted reproduction techniques in the endangered Iberian lynx.

View Article and Find Full Text PDF

Hibernation is a physiological adaptation to overcome extreme environmental conditions. It is characterized by prolonged periods of torpor interrupted by temporary arousals during winter. During torpor, body functions are suppressed and restored rapidly to almost pre-hibernation levels during arousal.

View Article and Find Full Text PDF

In the neuronal system, polysialic acid (polySia) is known to be involved in several cellular processes such as the modulation of cell-cell interactions. This highly negatively-charged sugar moiety is mainly present as a post-translational modification of the neural cell adhesion molecule (NCAM). More than 20 years ago, differently glycosylated forms of NCAM were detected in the ovaries.

View Article and Find Full Text PDF

European lynx species demonstrate an atypical ovarian cycle compared to other felids. The physiological persistence of corpora lutea (CLs), reflected in constantly elevated progesterone (P4) concentrations in serum, is thought to ensure a seasonal monooestrus. Moreover, the coexistence of CLs from a recent ovulation (freshCLs) and persistent CLs from previous years (perCLs) on the same ovary has been proven.

View Article and Find Full Text PDF

In the present study, we aimed to histologically stage and characterize the structural life span of the CL in the domestic cat. Moreover, the intraluteal levels of progesterone and estrogens were determined throughout the pregnant and nonpregnant (pseudopregnant, PP) luteal phases. On the basis of observed histomorphology of CL, the following stages were identified: CL formation (preimplantation period, PP1), development/maintenance (Days 10-36 of pregnancy, PP2), early regression (Days 38 and 39 of pregnancy, PP3), late regression (Day 48 of pregnancy, PP4), and corpus albicans.

View Article and Find Full Text PDF

In domestic cats, luteal phases of pregnancy and pseudopregnancy (non-pregnant luteal phase) differ in the course and level of plasma progesterone (P4). Therefore, we assumed differences in luteal steroidogenic capacities. Here we present a comprehensive analysis of intraluteal steroid biogenesis in the domestic cat.

View Article and Find Full Text PDF

Oviductin is known to be a key player providing a convenient environment for the process of fertilization affecting this by direct interaction with oocytes and sperm. As in vitro embryo production in the context of assisted reproduction for endangered felids is still in the process of optimization, oviductin might be used to improve IVF results. Recombinant His-tagged feline oviductin was expressed by transformed Escherichia coli BL21DE3 cells.

View Article and Find Full Text PDF

Roe deer (Capreolus capreolus) are seasonal breeders and cyclic structural changes of roe bucks' testis come along with a totally arrested (winter) and a highly activated spermatogenesis (summer). For this reason, roe buck represents an interesting model to study general mechanisms of initiation and termination of spermatogenesis. We investigated if polysialic acid (polySia)-a linear homopolymer of α2,8-linked sialic acids, which could act as a negative regulator of cell-cell adhesion-might be involved in the activation and/or inactivation of spermatogenesis.

View Article and Find Full Text PDF

Ovarian and placental steroids are essential for the maintenance of pregnancy. In some mammals it is evident that the placenta is responsible for the production of steroids. However, in the domestic cat, steroid secretion from the placenta has not yet been elucidated.

View Article and Find Full Text PDF