Lipophagy contributes to long-term storage of spermatozoa in the epididymis of the Chinese soft-shelled turtle Pelodiscus sinensis

Spermatozoa are known to be stored in the epididymis of the Chinese soft-shelled turtle Pelodiscus sinensis for long periods after spermiation from the testes, but the molecular mechanisms underlying this storage are largely unknown. In this study, epididymal spermatozoa were investigated to determine the potential molecular mechanism for long-term sperm storage in P. sinensis. Transmission electron microscopy (TEM) and Oil red O staining indicated that unusually large cytoplasmic droplets containing lipid droplets (LDs) were attached to the epididymal spermatozoa. However, the content of LDs decreased gradually with the sperm storage. LDs were surrounded by autophagic vesicles and sequestered as degradative cargo within autophagosome. Immunofluorescence and western blotting demonstrated that autophagy in spermatozoa increased gradually with the storage time. Invitro studies found that spermatozoa obtained from soft-shelled turtles in January can survive more than 40 days at 4°C. Furthermore, immunofluorescence and TEM showed that autophagy was involved in the degradation of LDs with the extension of sperm incubation. Inhibition of autophagy with 3-methyladenine significantly suppressed LD degradation. Moreover, adipose triglyceride lipase was involved in the metabolism of LDs. These findings indicate that lipophagy was activated to maximise LD breakdown, which contributes to long-term sperm storage in the epididymis of P. sinensis.

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Apoptotic-like changes in epididymal spermatozoa of soft-shelled turtles, Pelodiscus sinensis, during long-term storage at 4 ºC

Animal Reproduction Science ◽

10.1016/j.anireprosci.2019.04.014 ◽

2019 ◽

Vol 205 ◽

pp. 134-143 ◽

Cited By ~ 3

Author(s):

Hong Chen ◽

Yufei Huang ◽

Xuebing Bai ◽

Ping Yang ◽

Imran Tarique ◽

...

Keyword(s):

Pelodiscus Sinensis ◽

Long Term Storage ◽

Epididymal Spermatozoa ◽

Term Storage

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Dissolution Characteristics and Morphology of Large-sized Scorodite Particles Synthesized from Fe(II) and As(V) in Aqueous Solution

High Temperature Materials and Processes ◽

10.1515/htmp-2012-0080 ◽

2012 ◽

Vol 31 (4-5) ◽

pp. 451-458 ◽

Cited By ~ 3

Author(s):

S. Fujieda ◽

K. Shinoda ◽

T. Inanaga ◽

M. Abumiya ◽

S. Suzuki

Keyword(s):

Electron Microscopy ◽

Aqueous Solution ◽

Surface Defects ◽

Atmospheric Temperature ◽

Orthorhombic Structure ◽

X Ray ◽

Long Term Storage ◽

Transmission Electron ◽

Term Storage

AbstractA novel process for preparing scorodite particles with a diameter of approximately 20 µm from Fe(II) and As(V) in aqueous solution has been developed by DOWA Metals and Mining. In the present study, the dissolution characteristics of iron and arsenic from the scorodite particles synthesized by this process have been investigated under different conditions. The results show that the concentration of arsenic dissolved from the particles in aqueous solution is very low, but it has a complicated dependence on the temperature and pH of the solution. Transmission electron microscopy (TEM) with an energy dispersive X-ray spectrometer (EDS) was used to analyze the morphology, structure, and composition of the scorodite particles. The results indicate that the scorodite particles exhibit a nearly octahedral shape with planes composed of almost (111) planes in the orthorhombic structure. The concentration of iron at the surface of the particles is higher than that of iron inside of the particles. This characteristic morphology, along with the minimal surface defects of the scorodite particles, is considered to be responsible for the low dissolution of arsenic from the particles in aqueous solution. Atmospheric temperature and solution conditions were also found to be important for the safe, long-term storage of arsenic using scorodite particles.

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Interaction of Epididymal Epithelia and their Secretions with Spermatozoa Supports Functional and Morphological Changes During Long-Term Storage in the Chinese Soft-Shelled Turtle (Pelodiscus sinensis)

Microscopy and Microanalysis ◽

10.1017/s1431927620001373 ◽

2020 ◽

Vol 26 (3) ◽

pp. 542-550

Author(s):

Imran Tarique ◽

Mansoor Tariq ◽

Xuebing Bai ◽

Qu Wenjia ◽

Ping Yang ◽

...

Keyword(s):

Electron Density ◽

Morphological Changes ◽

Storage Period ◽

Sperm Storage ◽

Synthetic Activity ◽

High Electron ◽

Pelodiscus Sinensis ◽

Clear Cells ◽

Long Term Storage

AbstractPost-testicular maturation of spermatozoa is crucial for attaining the morphological and functional capabilities needed for successful fertilization. Epididymal epithelia offer a favorable environment for spermatozoa that are stored long term in the turtle epididymis; however, sperm–epithelial interactions during storage, which are enormously important for sperm functional and morphological maturation, are still largely unknown in turtles. The present study examined the epididymis during the sperm-storage period (November–April) in the Chinese soft-shelled turtle (Pelodiscus sinensis). Light and transmission electron microscopy were used to determine the cellular features of each epididymal segment (caput, corpus, and cauda) and their epithelial interactions with the spermatozoa. Spermatozoa were mainly located in the lumena of caput, corpus, and cauda epididymides. Numerous spermatozoa were bound to apical surfaces of the epithelia, and several were even embedded in the epithelial cytoplasm of the caput and corpus epididymides. No embedded spermatozoa were found in the cauda epididymis. In all epididymal segments, principal and clear cells showed the synthetic activity, evidenced by a well-developed endoplasmic reticulum network and high and low electron-dense secretory materials, respectively. Principal and clear cells in the caput and corpus segments showed embedded spermatozoa in electron-dense secretions and in the lipid droplets within the cytoplasm. No lysosomes were observed around the embedded spermatozoa. The lumena of the caput and corpus segments showed few apocrine and low electron density secretions. In the lumen of the cauda epididymidis, different secretions, such as holocrine with low and high electron density and their fragmentation, apocrine, and dictyosome, were found and are summarized. Altogether, sperm physical interactions with secretions either in the cytoplasm of epithelium or in the lumen may support the viability, morphological maintenance, and transfer of various proteins involved in long-term sperm storage in the turtle. This interaction could help us to understand the mechanisms of long-term sperm storage and provide more insights into the reproductive strategies of turtle sperm preservation.

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COMPARISON OF LONG-TERM STORAGE IN CHEMICAL FIXATIVES ON MORPHOLOGY AND ANATOMY OF SUPERDWARF WHEAT

HortScience ◽

10.21273/hortsci.31.6.918f ◽

1996 ◽

Vol 31 (6) ◽

pp. 918F-919

Author(s):

W.F. Campbell ◽

T. Strickland ◽

F.B. Salisbury ◽

P.S. Hole ◽

L. Gillespie ◽

...

Keyword(s):

Cellular Structure ◽

Vascular System ◽

Space Station ◽

Wheat Seedlings ◽

Long Term Storage ◽

Transmission Electron ◽

Electron Microscopical ◽

Cellular Components ◽

Term Storage

Wheat (Triticum aestivum L. cv. SuperDwarf) plants grown in the microgravity of space aboard the Russian space station Mir and sampled for morphological and anatomical comparison to those ex-posed to gravity on earth will be stored in chemical fixative for relatively long periods of time. Our objective was to examine, evaluate, and verify that the integrity of the vascular system and cellular components of wheat plants is maintained following storage in a chemical fixative. In ground-based studies, wheat seedlings were harvested on days 9, 28, and 68 and preserved in 4% formaldehyde: 1% glutaraldehyde (4F: 1G) fixative, adjusted to pH 7.2. Samples of leaves and/or stems were taken from these stocks after various times in storage (24 h, 1, 6, 12, and 24 months), dehydrated, and embedded in Spurr's resin. Semi-thin (1 μm) and thin (50–70 nm) sections were examined by light and transmission electron microscopy. Overall, there seems to be no major artifacts in the cellular structure. The plasmalemma and other organelles appeared normal in this fixative. Use of differential chromophores suggests that enzyme localizations at both the light and electron microscopical levels are not adversely affected by long-term storage. (Supported by NASA Grant NCC 2-831 and the Utah Agr. Expt. Station.)

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Comparison of methods for pre-processing, exosome isolation, and RNA extraction in unpasteurized bovine and human milk

PLoS ONE ◽

10.1371/journal.pone.0257633 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0257633

Author(s):

Sanoji Wijenayake ◽

Shafinaz Eisha ◽

Zoya Tawhidi ◽

Michael A. Pitino ◽

Michael A. Steele ◽

...

Keyword(s):

Human Milk ◽

Biological Fluid ◽

Rna Extraction ◽

Bovine Milk ◽

Protein Markers ◽

Long Term Storage ◽

Transmission Electron ◽

Cellular Debris ◽

Term Storage

Milk is a highly complex, heterogeneous biological fluid that contains non-nutritive, bioactive extracellular vesicles called exosomes. Characterization of milk-derived exosomes (MDEs) is challenging due to the lack of standardized methods that are currently being used for milk pre-processing, storage, and exosome isolation. In this study, we tested: 1) three pre-processing methods to remove cream, fat, cellular debris, and casein proteins from bovine milk to determine whether pre-processing of whole milk prior to long-term storage improves MDE isolations, 2) the suitability of two standard exosome isolation methods for MDE fractionation, and 3) four extraction protocols for obtaining high quality RNA from bovine and human MDEs. MDEs were characterized via Transmission Electron Microscopy (TEM), Nanoparticle Tracking Analysis (NTA), and western immunoblotting for CD9, CD63, and Calnexin protein markers. We also present an optimized method of TEM sample preparation for MDEs. Our results indicate that: 1) Removal of cream and fat globules from unpasteurized bovine milk, prior to long-term storage, improves the MDE yield but not purity, 2) Differential ultracentrifugation (DUC) combined with serial filtration is better suited for bovine MDE isolation compared to ExoQuick (EQ) combined with serial filtration, however both methods were comparable for human milk, and 3) TRIzol LS is better suited for RNA extraction from bovine MDEs isolated by EQ and DUC methods. 4) TRIzol LS, TRIzol+RNA Clean and Concentrator, and TRIzol LS+RNA Clean and Concentrator methods can be used for RNA extractions from human MDEs isolated by EQ, yet the TRIzol LS method is better suited for human MDEs isolated by DUC. The QIAzol + miRNeasy Mini Kit produced the lowest RNA yield for bovine and human MDEs.

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COMPARISON OF LONG-TERM STORAGE IN CHEMICAL FIXATIVES ON MORPHOLOGY AND ANATOMY OF SUPERDWARF WHEAT

HortScience ◽

10.21273/hortsci.31.6.918 ◽

1996 ◽

Vol 31 (6) ◽

pp. 918-919

Author(s):

W.F. Campbell ◽

T. Strickland ◽

F.B. Salisbury ◽

P.S. Hole ◽

L. Gillespie ◽

...

Keyword(s):

Cellular Structure ◽

Vascular System ◽

Space Station ◽

Wheat Seedlings ◽

Long Term Storage ◽

Transmission Electron ◽

Electron Microscopical ◽

Cellular Components ◽

Term Storage

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Modelling of Moisture Movement in Wood during Outdoor Storage

Nonlinear Analysis Modelling and Control ◽

10.15388/na.2001.6.1.15210 ◽

2001 ◽

Vol 6 (2) ◽

pp. 3-14 ◽

Cited By ~ 23

Author(s):

R. Baronas ◽

F. Ivanauskas ◽

I. Juodeikienė ◽

A. Kajalavičius

Keyword(s):

Experimental Data ◽

Finite Difference ◽

Climatic Conditions ◽

Two Dimensional ◽

Moisture Movement ◽

Finite Difference Technique ◽

Long Term Storage ◽

Space Formulation ◽

Term Storage

A model of moisture movement in wood is presented in this paper in a two-dimensional-in-space formulation. The finite-difference technique has been used in order to obtain the solution of the problem. The model was applied to predict the moisture content in sawn boards from pine during long term storage under outdoor climatic conditions. The satisfactory agreement between the numerical solution and experimental data was obtained.

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