Expression of FGF2 and TGFalpha and testis morphology during testicular hypertrophy subsequent to hemicastration in the neonatal boar

The objective was to ascertain fibroblast growth factor-2 (FGF2), epidermal growth factor (EGF), and transforming growth factor-alpha (TGFalpha) mRNA expression and testis morphology during accelerated testicular growth after hemicastration in the neonatal boar. On Day 10 after birth (Day 0), boars were assigned to control (n = 28), no treatment; hemicastrated (n = 28), left testis removed. The right testis in both groups (n = 7) was removed on Days 5, 10, 15, and 20. Expression of mRNA for FGF2, EGF, and TGFalpha was determined by qRT-PCR using TaqMan. Testicular morphology was determined on Day 15. On Day 10, hemicastrated boars had a greater (P = 0.01) testis weight (6.2 +/- 0.8 g; mean +/- SEM) than controls (4.3 +/- 0.4 g) and on Day 15 testis weight in hemicastrated boars (8.8 +/- 0.8 g) was twice (P < 0.01) that of control boars (4.2 +/- 0.3 g). Seminiferous tubule volume was approximately doubled in hemicastrated boars (P < 0.01) and was associated with an increase (P < 0.01) in Sertoli cell number. Interstitial compartment volume was greater (P < 0.01) in hemicastrated boars. Leydig cell numbers were similar (P = 0.14) but volume was greater (P < 0.01) for hemicastrates. There were no differences (P > 0.05) between control and hemicastrated boars in TGFalpha or FGF2 expression on Day 5 or Day 10, and EGF was not detected. It was concluded that upregulation of TGFalpha or FGF2 expression is not a pre-requisite for enhanced testicular growth and increased Sertoli cell proliferation that occurs subsequent to hemicastration in the neonatal boar.     

Alterations in the testis of hormone sensitive lipase-deficient mice is associated with decreased sperm counts, sperm motility, and fertility

Hormone-sensitive lipase (HSL, Lipe, E.C.3.1.1.3) functions as a triglyceride and cholesteryl esterase, supplying fatty acids, and cholesterol to cells. Gene-targeted HSL-deficient (HSL(-/-)) mice reveal abnormal spermatids and are infertile at 24 weeks after birth. The purpose of this study was to follow the evolution of spermatid abnormalities as HSL(-/-) mice age, characterize sperm motility in older HSL(-/-) mice, and determine if mice expressing a human testicular HSL transgene (HSL(-/-)ttg) produce normal motile sperm. In situ hybridization indicated that HSL is expressed exclusively in steps 5-16 spermatids, but not in Sertoli cells. In HSL(-/-) mice, abnormalities were evident in step 16 spermatids at 5 weeks after birth, with defects progressively increasing in spermatids with age. The defects included multinucleation of spermatids, abnormal shapes and a reduction of elongating spermatids. In older HSL(-/-) mice, sperm counts appeared reduced by 42%, but this value was lower because samples were compromised by the presence of small degenerating germ cells in addition to sperm, both of which appeared of similar size and density. Sperm motility was dramatically reduced with only 11% classified as motile in HSL(-/-) mice compared to 76-78% of sperm in wild-type and HSL(-/-)ttg mice. Sperm morphology, counts, and motility were normal in HSL(-/-)ttg mice, as was their fertility. Collectively, the data indicate that HSL deficiency results in abnormal spermatid development with defects arising at 5 weeks of age and progressively increasing at later ages. HSL(-/-) mice also show a dramatic reduction in sperm counts and motility and are infertile.     

睾丸支持细胞紧密连接的动力学调控

在睾丸精子发生的过程中,处于细线期和细线前期的精母细胞必须从生精上皮的基底室进入近腔室,这样形态上发育完全的精子才能在精子释放时进入到生精小管的内腔。显然,构成血-睾屏障的支持细胞间紧密连接的开放和关闭受到一系列信号分子的调节。已经发现的对该过程起调控作用的信号分子包括：转化生长因子β3(TGFβ3)、闭锁蛋白、PKA、PKC等。现就该领域研究的新进展以及可用于研究紧密连接动力学的一些模型进行综述。     

Tissue-Characteristic Expression of Mouse Proteome

The mouse is a valuable model organism for biomedical research. Here, we established a comprehensive spectral library and the data-independent acquisition–based quantitative proteome maps for 41 mouse organs, including some rarely reported organs such as the cornea, retina, and nine paired organs. The mouse spectral library contained 178,304 peptides from 12,320 proteins, including 1678 proteins not reported in previous mouse spectral libraries. Our data suggested that organs from the nervous system and immune system expressed the most distinct proteome compared with other organs. We also found characteristic protein expression of immune-privileged organs, which may help understanding possible immune rejection after organ transplantation. Each tissue type expressed characteristic high-abundance proteins related to its physiological functions. We also uncovered some tissue-specific proteins which have not been reported previously. The testis expressed highest number of tissue-specific proteins. By comparison of nine paired organs including kidneys, testes, and adrenal glands, we found left organs exhibited higher levels of antioxidant enzymes. We also observed expression asymmetry for proteins related to the apoptotic process, tumor suppression, and organ functions between the left and right sides. This study provides a comprehensive spectral library and a quantitative proteome resource for mouse studies.     

Reproductive exocrine and endocrine profiles and their seasonality in male langur monkeys (Presbytis entellus entellus)

The reproductive exocrine and endocrine profiles in male langurs are reported with an emphasis on seasonality. The animals showed positive response to electroejaculation throughout the year. The sperm concentration varied between 10–383 × 10⁶/ejaculation with wide fluctuations all through the year. No appreciable changes in the motility and percent live sperm were observed throughout the year. The levels of seminal fructose and magnesium remained unchanged throughout the year, while acid phosphatase showed wide fluctuations. Citric acid showed elevation during February and March and LDH showed elevated levels during April and May. The annual range of serum testosterone was 6–34 nMol/l with a peak during July. Cortisol ranged between 575–1587 nMol/l and prolactin ranged between 107–900 mU/l. Wide fluctuations were observed in hormonal levels. No seasonality was exhibited in the seminiferous tubule diameter, nuclear diameter of Sertoli cells and Leydig cells, and the cholesterol, glycogen, and sialic acid contents of testis. None of the parameters studied have shown any correlation with season. The results suggest that the male langurs lack seasonality in their reproductive exocrine and endocrine profiles and thus could be used as model for research in human reproduction.     

Immune proteasomes and immunity

A lot of facts that require understanding have been accumulated since immune proteasomes were discovered and their relationship with the immune response was established. For example, why are immune proteasomes present in all studied mammalian organs and tissues, including nonlymphoid tissues? What is responsible for differences in the ratio of immune to constitutive proteasomes in different organs? Are the functions of immune proteasomes related to the immune response alone, as was shown initially, or not? Are immune proteasomes formed simultaneously in different organs during ontogenesis? An attempt is made in this review to answer these and other related questions.     

Temporal analyses of postnatal liver development and maturation by single-cell transcriptomics

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EGFR Signaling Stimulates Autophagy to Regulate Stem Cell Maintenance and Lipid Homeostasis in the Drosophila Testis

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