Anatomy and Function of the Reproductive Tract in the Captive Male Tree Shrew (Tupaia belangeri)

The importance of zinc for male fertility only emerged recently, being propelled in part by consumer interest in nutritional supplements containing ionic trace minerals. Here, we review the properties, biological roles and cellular mechanisms that are relevant to zinc function in the male reproductive system, survey available peer-reviewed data on nutritional zinc supplementation for fertility improvement in livestock animals and infertility therapy in men, and discuss the recently discovered signaling pathways involving zinc in sperm maturation and fertilization. Emphasis is on the zinc-interacting sperm proteome and its involvement in the regulation of sperm structure and function, from spermatogenesis and epididymal sperm maturation to sperm interactions with the female reproductive tract, capacitation, fertilization, and embryo development. Merits of dietary zinc supplementation and zinc inclusion into semen processing media are considered with livestock artificial insemination (AI) and human assisted reproductive therapy (ART) in mind. Collectively, the currently available data underline the importance of zinc ions for male fertility, which could be harnessed to improve human reproductive health and reproductive efficiency in agriculturally important livestock species. Further research will advance the field of sperm and fertilization biology, provide new research tools, and ultimately optimize semen processing procedures for human infertility therapy and livestock AI.

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Carboxylesterase overexpression in the male reproductive tract: a universal safeguarding mechanism?

Reproduction Fertility and Development ◽

10.1071/rd99011 ◽

1999 ◽

Vol 11 (3) ◽

pp. 133 ◽

Cited By ~ 16

Author(s):

A. T. Mikhailov ◽

M. Torrado

Keyword(s):

Reproductive Tract ◽

Expression Patterns ◽

Cell Lineage ◽

Environmental Chemicals ◽

Male Reproductive Tract ◽

Morphological Organization ◽

Associated Functions ◽

And Function ◽

Hypothetical Explanation

Data on expression patterns of carboxylesterases in the male reproductive tract of different animal groups (i.e. bivalve mollusks, fruitflies and rodents) are summarized to highlight some particularly interesting questions in the context of sperm differentiation, maturation and function. The male reproduc-tive system, in spite of extreme variation in the anatomical/morphological organization in different species, is characterized by similar patterns of male-dependent carboxylesterase overexpression. The phenomenon of conserved carboxylesterase overexpression indicates similar male sex-associated functions of the enzymes. There is possible evidence of carboxylesterase recruitment by male reproductive-tract tissues indi-cating that it could be adaptive for spermatogenesis, sperm maturation and sperm use. Moreover, this idea can be extended to include a sperm cell lineage protection. This issue is discussed in the light of recent data on environmental reproductive xenobiotics that can provide a basis for a hypothetical explanation of car-boxylesterase overexpression in the male reproductive tract. Based on a well-known role of car-boxylesterases in detoxification of environmental chemicals such as organophosphate pesticides, it is proposed that various male genital tract carboxylesterases may be characterized by a similar physiological function to protect the male reproductive system against xenobiotic influences that could provoke its dys-function, thus altering sperm differentiation and maturation.

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MHC class I genes of the tree shrew Tupaia belangeri

Immunogenetics ◽

10.1007/s00251-001-0401-0 ◽

2002 ◽

Vol 53 (10-11) ◽

pp. 984-988 ◽

Cited By ~ 12

Author(s):

Perris Flügge, Eberhard Fuchs, Ebe

Keyword(s):

Mhc Class I ◽

Tree Shrew ◽

Class I ◽

Tupaia Belangeri

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