scholarly journals In Vitro Hepatic Assessment of Cineole and Its Derivatives in Common Brushtail Possums (Trichosurus vulpecula) and Rodents

Biology ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1326
Author(s):  
Ravneel R. Chand ◽  
Mhairi Nimick ◽  
Belinda Cridge ◽  
Rhonda J. Rosengren
Keyword(s):  
Catalytic Activity ◽  
Management Strategies ◽  
Brushtail Possum ◽  
Trichosurus Vulpecula ◽  
Cytochrome P450 3A ◽  
Phascolarctos Cinereus ◽  
Catalytic Activities ◽  
Rats And Mice ◽  
Drug Metabolising Enzymes

Folivore marsupials, such as brushtail possum (Trichosurus Vulpecula) and koala (Phascolarctos cinereus), can metabolise higher levels of dietary terpenes, such as cineole, that are toxic to eutherian mammals. While the highly efficient drug metabolising enzymes, cytochrome P450 3A (CYP3A) and phase II conjugating enzymes (UDP-glucuronosyltransferase, UGT), are involved in the metabolism of high levels of dietary terpenes, evidence for inhibitory actions on these enzymes by these terpenes is scant. Thus, this study investigated the effect of cineole and its derivatives on catalytic activities of hepatic CYP3A and UGT in mice, rats, and possums. Results showed that cineole (up to 50 µM) and its derivatives (up to 25 µM) did not significantly inhibit CYP3A and UGT activities in mice, rats, and possums (both in silico and in vitro). Interestingly, basal hepatic CYP3A catalytic activity in the possums was ~20% lower than that in rats and mice. In contrast, possums had ~2-fold higher UGT catalytic activity when compared to mice and rats. Thus, these basal enzymatic differences may be further exploited in future pest management strategies.

scholarly journals Comparative Study of Brain Ontogeny: Marsupials, Humans and Other Eutherians

2021 ◽  
Author(s):  
Carmen De Miguel ◽  
Arthur Saniotis ◽  
Agata Cieslik ◽  
Maciej Henneberg
Keyword(s):  
Body Weight ◽  
Human Brain ◽  
Rhesus Monkeys ◽  
Brain Morphology ◽  
Trichosurus Vulpecula ◽  
Brain Growth ◽  
Phascolarctos Cinereus ◽  
Macropus Eugenii ◽  
Mental Abilities ◽  
Rats And Mice

Abstract The human brain is commonly considered unique in its growth pattern, especially in its fast growth in early infancy. Consequently, many researchers were encouraged to find peculiarities in the human brain and development which differentiated it from the brains of other animals. In this paper, we argue that the pattern of human brain growth is not different from that of other mammals, both marsupials and eutherians. Thus, our study, challenges the notion of the uniqueness of the human brain and its development indicating that specifically human mental abilities are not a result of brain morphology or size. In order to test our hypothesis we studied the ontogeny of brain weight relative to body weight using pouch young sample of 43 koalas (Phascolarctos cinereus), 28 possums (Trichosurus vulpecula), and 36 tammar wallabies (Macropus eugenii) preserved in a solution of 10 % buffered formalin. We also analysed the growth of brain vs. body size in all eutherian species falling into this group (humans, rhesus monkeys, dogs, cats, rats and mice).

Ionic calcium levels in oviduct explant-conditioned media from an Australian marsupial, the brushtail possum (Trichosurus vulpecula) and its relevance to in vitro fertilization

Zygote ◽  
2003 ◽  
Vol 11 (4) ◽  
pp. 285-291 ◽  
Author(s):  
K.S. Sidhu ◽  
K.E. Mate ◽  
F.C. Molinia ◽  
D.K. Berg ◽  
J.C. Rodger
Keyword(s):  
Calf Serum ◽  
Explant Culture ◽  
Conditioned Media ◽  
Brushtail Possum ◽  
Trichosurus Vulpecula ◽  
Large Variability ◽  
Vitro Fertilization ◽  
Ionic Calcium ◽  
Australian Marsupial

Gametes from the brushtail possum (Trichosurus vulpecula), an Australian marsupial, require exposure to oviductal cells and/or their secretions before sperm binding and penetration of the zona pellucida can occur. Sperm-egg fusion, the next critical step in fertilization has not previously been reported in vitro. Here we describe the refinement of an oviduct epithelial cell (OEC) explant culture system using two different media to obtain in vitro sperm-egg fusion in the brushtail possum for the first time. Conditioned media from OEC explant cultures were supplemented with either 1% fetal calf serum (FCS) or 1mg/ml polyvinyl alcohol and used for co-culture of epididymal sperm and superovulated eggs. Under these conditions zona penetration rates varied from 0 to 46% and sperm-egg fusion from 0 to 20%. Analysis of explant conditioned media indicated that qualitative and quantitative differences between batches could account, at least partially, for the large variability in zona penetration rates. Conditioned media that contained approximately 1mM of ionic calcium were most effective for achieving sperm capacitation, zona binding, and penetration and sperm-egg fusion. The reorientation of the sperm head to T-shape, an indicator of capacitation in the brushtail possum, was closely linked with the concentration of calcium present in vitro.

scholarly journals In Vitro Glycation of Aminotransferases: A Process Closely Depending on the Employed Experimental Conditions

2002 ◽  
Vol 45 (3) ◽  
pp. 89-92
Author(s):  
Martin Beránek ◽  
Jaroslav Dršata ◽  
Vladimír Palička
Keyword(s):  
Catalytic Activity ◽  
Experimental Design ◽  
Incubation Period ◽  
Alanine Aminotransferase ◽  
Initial Activity ◽  
Experimental Conditions ◽  
Catalytic Activities ◽  
Incubation Temperatures ◽  
Alt Activity

The aim of the present study is to investigate the influence of various experimental conditions, i.e., two different concentrations of D-fructose as a rapidly glycating substance and three incubation temperatures, on the glycation reaction of alanine aminotransferase (ALT, EC 2.6.1.2) and aspartate aminotransferase (AST, EC 2.6.1.1) expressed by decreasing catalytic activities of the enzymes during a 56 day in vitro incubation period. D-fructose in the concentration of 50 mmol/l did not inhibit the catalytic activity of either enzyme at 4 °C, partially inhibited AST activity in samples incubated at 25 °C (to 40% of the initial activity), and completely inhibited this enzyme at 37 °C at the end of the incubation period. In the presence of the same concentration of D-fructose, ALT showed no catalytic activity after 35 days at 25 °C or after 10 days at 37 °C. In 500 mmol/l D-fructose, complete AST inhibition was observed after 35 days (25 °C) or 20 days (37 °C), and no ALT activity was found on day 20 at either 25 °C or 37 °C. Taking into account the highest possible stability of enzymes, we suppose that a three-week observation of their residual catalytic activity in the presence of 50 mmol/l D-fructose at the temperature of 25 °C seems to be the most prospective experimental design for future glycation studies with aminotransferases under the influences of drugs.

229. Identification of transforming growth factor beta2 (TGF-β2) and its receptors TGF-βRI and TGF-βRII in the possum (Trichosurus vulpecula) prostate: evidence of seasonal changes

2008 ◽  
Vol 20 (9) ◽  
pp. 29
Author(s):  
H. Martyn ◽  
K. Pugazhenthi ◽  
B. McLeod ◽  
H. D. Nicholson
Keyword(s):  
Growth Factor ◽  
Epithelial Cells ◽  
Stromal Cells ◽  
Seasonal Changes ◽  
Transforming Growth Factor ◽  
Brushtail Possum ◽  
Trichosurus Vulpecula ◽  
Western Blots ◽  
Prostate Growth

Benign Prostatic Hyperplasia is an enlargement of the prostate affecting the ageing male population. The common Brushtail possum (Trichosurus vulpecula) has been identified as a possible model to study factors regulating prostate growth because its prostate grows and regresses seasonally. Transforming growth factor Beta 2 (TGF-β2) is present in human prostatic tissue. In vitro, TGF-β inhibits epithelial cell, but stimulates stromal cell proliferation (Mori et al. 1990). TGF-β2 binds to TGF-β receptor II (TGF-βRII), which then recruits the type 1 receptor (TGF-βRI) (Saez et al. 1998) The aim of this study was to identify any seasonal changes in expression of TGF-β2 and its receptors in the possum prostate. Six wild-caught possums were sacrificed in each of the months of January, March, May, July, September and November. The prostates were divided into a cranial and caudal region and immunohistochemistry and Western Blot analysis performed. In each animal the glandular and periurethral areas of the caudal and cranial prostates were examined separately. Immunohistochemistry identified the presence of TGF-β2 in both the stromal and epithelial cells of the glandular and periurethral areas of the cranial and caudal regions. In the cranial tissue, more immuno-positive stromal cells than epithelial cells were present, whereas in the caudal tissue immuno-reactivity was predominantly localised to the epithelial cells. Analysis of the western blots suggested that TGF-β2 expression was lowest immediately before and during the breeding season (March, May). Both TGF-βRI and TGF-βRII were identified in all regions of the prostate. Furthermore, immunohistochemistry revealed that the receptors were co-localised in the epithelial and stromal cells in all areas. TGF-β2 and its receptors are present in the possum prostate. TGF-β2 localisation varies between the caudal and cranial regions and as predicted from in vitro experiments TGF-β2 expression decreases during prostate growth. (1) Mori H. et al. (1990). The Prostate, 16, 71 - 80. (2) Saez C. et al. (1998). The Prostate, 37, 84 - 90.

In vitro culture of brushtail possum (Trichosurus vulpecula) epididymal epithelium and induction of epididymal sperm maturation in co-culture

Reproduction ◽  
2000 ◽  
pp. 1-14 ◽  
Author(s):  
M Lin ◽  
X Zhang ◽  
R Murdoch ◽  
RJ Aitken
Keyword(s):  
Sperm Maturation ◽  
Brushtail Possum ◽  
Trichosurus Vulpecula ◽  
Epididymal Sperm ◽  
Cell Monolayers ◽  
Progressive Motility ◽  
Cell Culture Systems ◽  
Marsupial Species ◽  
Morphological Maturation

A medium modified from eutherian systems was used to culture epididymal epithelial cells of the brushtail possum (Trichosurus vulpecula) for more than 2 months. Epididymal tubule fragments from the caput, corpus and cauda epididymides were used to generate cell monolayers. All three epididymal cell culture systems supported maturational changes in marsupial spermatozoa and enabled immature possum spermatozoa to differentiate from a T-shape to a streamlined shape, accompanied by the development of progressive motility after co-culture with 7-day-old cultured epididymal cell monolayers. This epididymal cell and sperm co-culture system for marsupial species may facilitate the identification of specific epithelial factors that affect sperm maturation, particularly in a species in which morphological maturation is readily visible.

Spermophagy by follicular cumulus cells in the common brushtail possum Trichosurus vulpecula following co-culture of sperm and immature ovarian oocytes.

2006 ◽  
Vol 28 (1) ◽  
pp. 111 ◽  
Author(s):  
J. A. Chapman ◽  
W. G. Breed
Keyword(s):  
Pilot Study ◽  
Zona Pellucida ◽  
Cumulus Cells ◽  
Brushtail Possum ◽  
Trichosurus Vulpecula ◽  
Epididymal Sperm ◽  
Cumulus Oophorus ◽  
The Common ◽  
Common Brushtail Possum

This is a pilot study to investigate the effects of incubating cumulus oophorus-encased ovarian oocytes of the common brushtail possum (Trichosurus vulpecuila) with cauda epididymal sperm to determine if sperm could penetrate the cumulus oophous and thereby remove the need to mechanically denude in vitro matured ovarian oocyctes, and if sperm-zona binding would occur under these conditions. No fertilisation or sperm-zona pellucida binding took place. Some spermatozoa within the cumulus oophorus layer were phagocytosed.

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