Beneficial effects of dietary papain supplementation in juvenile sterlet (Acipenser ruthenus): Growth, intestinal topography, digestive enzymes, antioxidant response, immune response, and response to a challenge test

DNA damage caused by exogenous or endogenous factors is a common challenge for developing fish embryos. DNA damage repair (DDR) pathways help organisms minimize adverse effects of DNA alterations. In terms of DNA repair mechanisms, sturgeons represent a particularly interesting model due to their exceptional genome plasticity. Sterlet (Acipenser ruthenus) is a relatively small species of sturgeon. The goal of this study was to assess the sensitivity of sterlet embryos to model genotoxicants (camptothecin, etoposide, and benzo[a]pyrene), and to assess DDR responses. We assessed the effects of genotoxicants on embryo survival, hatching rate, DNA fragmentation, gene expression, and phosphorylation of H2AX and ATM kinase. Exposure of sterlet embryos to 1 µM benzo[a]pyrene induced low levels of DNA damage accompanied by ATM phosphorylation and xpc gene expression. Conversely, 20 µM etoposide exposure induced DNA damage without activation of known DDR pathways. Effects of 10 nM camptothecin on embryo development were stage-specific, with early stages, before gastrulation, being most sensitive. Overall, this study provides foundational information for future investigation of sterlet DDR pathways.

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The Respiratory Commensal Bacterium Dolosigranulum pigrum 040417 Improves the Innate Immune Response to Streptococcus pneumoniae

Microorganisms ◽

10.3390/microorganisms9061324 ◽

2021 ◽

Vol 9 (6) ◽

pp. 1324

Author(s):

Fernanda Raya Tonetti ◽

Mikado Tomokiyo ◽

Ramiro Ortiz Moyano ◽

Sandra Quilodrán-Vega ◽

Hikari Yamamuro ◽

...

Keyword(s):

Immune Response ◽

Streptococcus Pneumoniae ◽

Innate Immune Response ◽

Pneumococcal Infection ◽

Innate Immune ◽

Nasal Administration ◽

Commensal Bacterium ◽

Beneficial Effects ◽

Immunological Mechanisms ◽

Immunomodulatory Properties

Previously, we demonstrated that the nasal administration of Dolosigranulum pigrum 040417 differentially modulated the respiratory innate immune response triggered by the activation of Toll-like receptor 2 in infant mice. In this work, we aimed to evaluate the beneficial effects of D. pigrum 040417 in the context of Streptococcus pneumoniae infection and characterize the role of alveolar macrophages (AMs) in the immunomodulatory properties of this respiratory commensal bacterium. The nasal administration of D. pigrum 040417 to infant mice significantly increased their resistance to pneumococcal infection, differentially modulated respiratory cytokines production, and reduced lung injuries. These effects were associated to the ability of the 040417 strain to modulate AMs function. Depletion of AMs significantly reduced the capacity of the 040417 strain to improve both the reduction of pathogen loads and the protection against lung tissue damage. We also demonstrated that the immunomodulatory properties of D. pigrum are strain-specific, as D. pigrum 030918 was not able to modulate respiratory immunity or to increase the resistance of mice to an S. pneumoniae infection. These findings enhanced our knowledge regarding the immunological mechanisms involved in modulation of respiratory immunity induced by beneficial respiratory commensal bacteria and suggested that particular strains could be used as next-generation probiotics.

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Role of Ca2+ in the IVM of spermatozoa from the sterlet Acipenser ruthenus

Reproduction Fertility and Development ◽

10.1071/rd16145 ◽

2017 ◽

Vol 29 (7) ◽

pp. 1319 ◽

Cited By ~ 4

Author(s):

Olga Bondarenko ◽

Borys Dzyuba ◽

Marek Rodina ◽

Jacky Cosson

Keyword(s):

Sperm Motility ◽

Seminal Fluid ◽

Mature Male ◽

Sperm Maturation ◽

Wolffian Duct ◽

Testicular Spermatozoa ◽

Acipenser Ruthenus ◽

Sterlet Acipenser Ruthenus ◽

Motility Parameters

The role of Ca2+ in sturgeon sperm maturation and motility was investigated. Sperm from mature male sterlets (Acipenser ruthenus) were collected from the Wolffian duct and testis 24 h after hormone induction. Testicular spermatozoa (TS) were incubated in Wolffian duct seminal fluid (WDSF) for 5 min at 20°C and were designated ‘TS after IVM’ (TSM). Sperm motility was activated in media with different ion compositions, with motility parameters analysed from standard video microscopy records. To investigate the role of calcium transport in the IVM process, IVM was performed (5 min at 20°C) in the presence of 2 mM EGTA, 100 µM Verapamil or 100 µM Tetracaine. No motility was observed in the case of TS (10 mM Tris, 25 mM NaCl, 50 mM Sucr with or without the addition of 2 mM EGTA). Both incubation of TS in WDSF and supplementation of the activation medium with Ca2+ led to sperm motility. The minimal Ca2+ concentration required for motility activation of Wolffian duct spermatozoa, TS and TSM was determined (1–2 nM for Wolffian duct spermatozoa and TSM; approximately 0.6 mM for TS). Motility was obtained after the addition of verapamil to the incubation medium during IVM, whereas the addition of EGTA completely suppressed motility, implying Ca2+ involvement in sturgeon sperm maturation. Further studies into the roles of Ca2+ transport in sturgeon sperm maturation and motility are required.

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Ultrastructural Localization of Intracellular Calcium During Spermatogenesis of Sterlet (Acipenser ruthenus)

Microscopy and Microanalysis ◽

10.1017/s1431927616011958 ◽

2016 ◽

Vol 22 (6) ◽

pp. 1155-1161 ◽

Cited By ~ 13

Author(s):

Amin Golpour ◽

Martin Pšenička ◽

Hamid Niksirat

Keyword(s):

Intracellular Calcium ◽

Developmental Stages ◽

Physiological Function ◽

Male Gamete ◽

Ultrastructural Localization ◽

Acrosomal Vesicle ◽

Acipenser Ruthenus ◽

Calcium Deposits ◽

Late Stages ◽

Sterlet Acipenser Ruthenus

AbstractCalcium regulates many intracellular events such as growth and differentiation during different stages of gamete development. The aim of this study was to localize and quantify the intracellular distribution of calcium during different developmental stages of spermatogenesis in sterlet, Acipenser ruthenus, using a combined oxalate–pyroantimonate technique. The distribution of calcium was described in spermatogonium, spermatocyte, spermatid, and spermatozoon stages. In the spermatogonium and spermatocyte, calcium deposits were mainly localized in the nucleus and cytoplasm. The spermatid had calcium in the nucleus, developing acrosomal vesicle, and cytoplasm. Intracellular calcium transformed from scattered deposits in spermatogonia and spermatocyte stages into an unbound form in spermatid and the spermatozoon. The proportion of area covered by calcium increased significantly (p<0.05) from early to late stages of spermatogenesis. The largest proportion of area covered by calcium was observed in the nucleus of the spermatozoon. In conclusion, although most of the intracellular calcium is deposited in limited areas of the spermatogonium and spermatocyte, it is present an unbound form in the larger area of spermatids and spermatozoa which probably reflects changes in its physiological function and homeostasis during the process of male gamete production in spermatogenesis.

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