Paternal levels of DNA damage in spermatozoa and maternal parity influence offspring mortality in an endangered ungulate

Understanding which factors influence offspring mortality rates is a major challenge since it influences population dynamics and may constrain the chances of recovery among endangered species. Most studies have focused on the effects of maternal and environmental factors, but little is known about paternal factors. Among most polygynous mammals, males only contribute the haploid genome to their offspring, but the possibility that sperm DNA integrity may influence offspring survival has not been explored. We examined several maternal, paternal and individual factors that may influence offspring survival in an endangered species (Gazella cuvieri). Levels of sperm DNA damage had the largest impact upon offspring mortality rates, followed by maternal parity. In addition, there was a significant interaction between these two variables, so that offspring born to primiparous mothers were more likely to die if their father had high levels of sperm DNA damage, but this was not the case among multiparous mothers. Thus, multiparous mothers seem to protect their offspring from the deleterious effects of sperm DNA damage. Since levels of sperm DNA damage seem to be higher among endangered species, more attention should be paid to the impact of this largely ignored factor among the viability of endangered species.     

Regulation of root growth by auxin and ethylene is influenced by phosphate supply in white clover (<Emphasis Type="Italic">Trifolium repens</Emphasis> L.)

The influence of P-supply on root system architecture (primary root length, number and total length of lateral roots) through the effects of ethylene (ACC) and auxin [1-naphthylacetic acid (NAA)] has been examined in the legume white clover (Trifolium repens L.). Higher concentrations (1 and 10 μM) of ACC and NAA (100 nM) inhibited growth, while lower concentrations (100 nM ACC, 5 nM NAA) either had no effect or stimulated growth in P-sufficient (1 mM Pi) roots. In response to low (10 μM) P, a stimulation of primary root growth, number of lateral roots and mean length of lateral roots was observed, while a super-stimulation of these growth parameters occurred in response to subsequent 100 nM ACC treatment suggesting that the low P treatment increased the sensitivity of the roots to ethylene. Examination of the primary roots of DR5p::GUS transformants suggests that this change in sensitivity induced by low P occurs through the promotion of auxin signalling/transport to the root apex. These results are discussed in terms of the role of ethylene and the significance of changes in sensitivity to the hormone in modulating root system architecture in response to low P-supply.     

On the morphology of spermatozoa of tuco-tucos, Ctenomys (Rodentia: Ctenomyidae): New data and its implications for the evolution of the genus

Sperm morphology was studied in 10 species of the caviomorph rodent Ctenomys. Ctenomys argentinus, C. conoueri, C. dorbigny and C.perrensis had symmetric spermatozoa with paddle-like heads. Ctenomys australis, C. mendocinus, C. porteousi, C. rionegrensis and Ctenomys sp., on the other hand, had spermatozoa with paddle-like heads but with the tail inserted at one side of the central axis and a nuclear caudal extension originating from the base of the head at the opposite side of the insertion of the tail and running parallel to the flagellum; these spermatozoa are referred to as simple-asymmetric. In C. yolandae, a complex-asymmetric morphological type not previously described for the genus was found. This type is characterized by the presence of two nuclear caudal extensions. Symmetric spermatozoa (total length = 52 pm) were shorter than asymmetric (both simple and complex) ones (total length = 87 pm). In spite of these differences, the relative size of heads, midpieces and tails were maintained in the three groups, representing 12%, I I YO and 88% of the average total length, respectively. Within each group of species bearing the same sperm type, a low interspecific variability both in morphological patterns and dimensions of sperm cells was observed. This low interspecific variability associated with the north to south geographical distribution of species having, respectively, symmetric and asymmetric spermatozoa, suggests that these characters appeared at an early stage in evolution of the group, and probably played an important role in the first steps of speciation by promoting reproductive isolation.     

Male reproductive health statement (XIIIth international symposium on Spermatology,may 9th–12th 2018, Stockholm,Sweden

On the occasion of the XIIIth International Symposium on Spermatology held from 9 to 13 May 2018 in Stockholm (Sweden), participants (guest speakers and audience) collectively felt the need to make a public statement on the general issue of male reproductive health. Our intention is to raise awareness of what we believe is a neglected area of research despite alarming situations around the world. The disclosure strategy desired by the co-authors is to bring it to the attention of the greatest number partly by considering co-publication in the various periodicals dealing with Reproductive Biology and Andrology. BaCA’s editorial office accepted this mission and found it natural that our periodical, the official journal of the French Andrology Society (SALF), should carry this message.     

Quantitative patterns of Hsps in tubular adenoma compared with normal and tumor tissues reveal the value of Hsp10 and Hsp60 in early diagnosis of large bowel cancer

Large bowel carcinogenesis involves accumulation of genetic alterations leading to transformation of normal mucosa into dysplasia and, lastly, adenocarcinoma. It is pertinent to elucidate the molecular changes occurring in the pre-neoplastic lesions to facilitate early diagnosis and treatment. Heat shock proteins (Hsps), many of which are molecular chaperones, are implicated in carcinogenesis, and their variations with tumor progression encourage their study as biomarkers. There are many reports on Hsps and cancer but none to our knowledge on their systematic quantification in pre-neoplastic lesions of the large bowel. We performed immunohistochemical determinations of Hsp10, Hsp60, Hsp70, and Hsp90 in biopsies of large bowel tubular adenomas with moderate grade of dysplasia and compared to normal mucosa and adenocarcinoma with a moderate grade of differentiation (G2). A significant elevation of Hsp10 and Hsp60 only, i.e., in the absence of elevation of Hsp70 or Hsp90, in both epithelium and lamina propria was found in tubular adenoma by comparison with normal mucosa. In contrast, adenocarcinoma was characterized by the highest levels of Hsp10 and Hsp60 in epithelium and lamina propria, accompanied by the highest levels of Hsp70 only in epithelium and of Hsp90 only in lamina propria, by comparison with normal and tubular adenoma counterparts. Hsp10 and Hsp60 are promising biomarkers for early diagnosis of tubular adenoma and for its differentiation from more advanced malignant lesions. Hsp10 and Hsp60 may be implicated in carcinogenesis from its very early steps and, thus, are potentially convenient targets for therapy.