189 research outputs found
Molecular Research on Reproductive Toxicity
Fertility rates in animals have shown a progressive decrease in recent decades, and reproductive toxicity is considered an important regulatory endpoint in health hazard assessment [...
Molecular and Histological Effects of Glyphosate on Testicular Tissue of the Lizard Podarcis siculus
The expansion of agriculture produces a steady increase in habitat fragmentation and degâ radation due to the increased use of pesticides and herbicides. Habitat loss and alteration associated with crop production play an important role in reptile decline, among which lizards are particularly endangered. In this study, we evaluated testicular structure, steroidogenesis, and estrogen receptor expression/localization after three weeks of oral exposure to glyphosate at 0.05 and 0.5 ÎŒg/kg body weight every other day in the field lizard Podarcis siculus. Our results show that glyphosate affected testicular morphology, reduced spermatogenesis, altered gap junctions and changed the localizaâ tion of estrogen receptors in germ cells, increasing their expression; the effects were mostly doseâ dependent. The result also demonstrates that glyphosate, at least at these concentrations, did not influence steroidogenesis. Overall, the data indicate that this herbicide can disturb the morphophysâ iology of the male lizardâs reproductive system, with obviously detrimental effects on their reproâ ductive fitness. The effects of glyphosate must be considered biologically relevant and could endanâ ger the reproductive capacity not only of lizards but also of other vertebrates, including humans; a more controlled and less intensive use of glyphosate in areas devoted to crop production would therefore be advisable
Exploring the Role of Estrogens in Lizard Spermatogenesis through the Study of Clomiphene and FSH Effects
Spermatogenesis is a fascinating biological process aiming to generate haploid spermatozoa from diploid spermatogonia through a
specific hormonal network between gonadotropins and steroids. Increasing evidence suggests that the primary female sex hormone
estrogen plays an active role in this process. This research points out on the role of estrogen during lizard spermatogenesis by using
three experimental approaches: (1) exposure to an analogue of nonsteroidal estrogen as Clomiphene citrate that acts both as
estrogen agonist and antagonist; (2) exposure to the gonadotropin FSH; and (3) exposures to FSH followed by Clomiphene.
Histological and immunohistochemical results demonstrate that in the lizard Podarcis sicula during the mating period,
Clomiphene as well as FSH determines the breakdown of spermatogenesis and the epididymal regression, presumably through
estrogens input as indirectly demonstrated by the appearance of ERα and vitellogenin in the liver. The ability of Clomiphene to
restore the gonadal natural condition after FSH treatment is also demonstrated. Finally, data indicate that lizard testis and
epididymis control their morphophysiology regulating the intracellular presence of ERα
Toxicological Impact of Rare Earth Elements (REEs) on the Reproduction and Development of Aquatic Organisms Using Sea Urchins as Biological Models
The growing presence of lanthanides in the environment has drawn the attention of the scientific community on their safety and toxicity. The sources of lanthanides in the environment include diagnostic medicine, electronic devices, permanent magnets, etc. Their exponential use and the poor management of waste disposal raise serious concerns about the quality and safety of the ecosystems at a global level. This review focused on the impact of lanthanides in marine organisms on reproductive fitness, fertilization and embryonic development, using the sea urchin as a biological model system. Scientific evidence shows that exposure to lanthanides triggers a wide variety of toxic insults, including reproductive performance, fertilization, redox metabolism, embryogenesis, and regulation of embryonic gene expression. This was thoroughly demonstrated for gadolinium, the most widely used lanthanide in diagnostic medicine, whose uptake in sea urchin embryos occurs in a time- and concentration-dependent manner, correlates with decreased calcium absorption and primarily affects skeletal growth, with incorrect regulation of the skeletal gene regulatory network. The results collected on sea urchin embryos demonstrate a variable sensitivity of the early life stages of different species, highlighting the importance of testing the effects of pollution in different species. The accumulation of lanthanides and their emerging negative effects make risk assessment and consequent legislative intervention on their disposal mandatory
Effects of Cadmium Exposure on Gut Villi in Danio rerio.
In aquatic organisms, cadmium exposure occurs from ovum to death and the route of
absorption is particularly wide, being represented by skin, gills and gastrointestinal tract, through
which contaminated water and/or preys are ingested. It is known that cadmium interferes with
the gut; however, less information is available on cadmium effects on an important component of
the gut, namely goblet cells, specialized in mucus synthesis. In the present work, we studied the
effects of two sublethal cadmium concentrations on the gut mucosa of Danio rerio. Particular attention
was paid to changes in the distribution of glycan residues, and in metallothionein expression in
intestinal cells. The results show that cadmium interferes with gut mucosa and goblet cells features.
The effects are dose- and site-dependent, the anterior gut being more markedly affected than the
midgut. Cadmium modifies the presence and/or distribution of glycans in the brush border and
cytoplasm of enterocytes and in the goblet cellsâ cytoplasm and alters the metallothionein expression
and localization. The results suggest a significant interference of cadmium with mucosal efficiency,
representing a health risk for the organism in direct contact with contamination and indirectly for the
trophic chain
High Fat Diet and Inflammation - Modulation of Haptoglobin Level in Rat Brain
Obesity and dietary fats are well known risk factors for neurodegenerative diseases. The analysis of specific markers, whose brain level can be affected by diet, might contribute to unveil the intersection between inflammation/obesity and neurodegeneration. Haptoglobin (Hpt) is an acute phase protein, which acts as antioxidant by binding free haemoglobin (Hb), thus neutralizing its pro-oxidative action. We previously demonstrated that Hpt plays critical functions in brain, modulating cholesterol trafficking in neurons, beta-amyloid (AÎČ) uptake by astrocyte, and limiting AÎČ toxicity on these cells. A major aim of this study was to evaluate whether a long term (12 or 24 weeks) high-fat diet (HFD) influences Hpt and Hb expression in rat hippocampus. We also assessed the development of obesity-induced inflammation by measuring hippocampal TNF-alpha, and the extent of protein oxidation by titrating nitro-tyrosine (N-Tyr). Hpt concentration was lower in hippocampus of HFD rats than in control animals, HFD was also associated in hippocampus with the increase of Hb level, inflammation and protein oxidative modification, as evidenced by the increase in the concentration of TNF-alpha and nitro-tyrosine. In fact, TNF-alpha concentration was higher in rats receiving HFD for 12 or 24 weeks compared to controls. N-Tyr concentration was more elevated in hippocampus of HFD than in control rats in both 12 weeks and 24 weeks groups. Finally, we found that the treatment of the human glial cells with cholesterol and fatty acids significantly impairs Hpt secretion in the extracellular compartment. We hypothesize that the HFD-dependent decrease of Hpt in hippocampus, as associated with Hb increase, might enhance the oxidative stress induced by free Hb. Altogether our data, identifying Hpt as a molecule modulated in the brain by dietary fats, may represent one of the first steps in the comprehension of the molecular mechanisms underlying the diet-related effects in the nervous system
Positive effects of physical activity in autism spectrum disorder: how influences behavior, metabolic disorder and gut microbiota
Autism spectrum disorder is a neurodevelopmental disorder characterized by social interactions and communication skills impairments that include intellectual disabilities, communication delays and self-injurious behaviors; often are present systemic comorbidities such as gastrointestinal disorders, obesity and cardiovascular disease. Moreover, in recent years has emerged a link between alterations in the intestinal microbiota and neurobehavioral symptoms in children with autism spectrum disorder. Recently, physical activity and exercise interventions are known to be beneficial for improving communication and social interaction and the composition of microbiota. In our review we intend to highlight how different types of sports can help to improve communication and social behaviors in children with autism and also show positive effects on gut microbiota composition
Difference in hepatic metallothionein content in Antarctic red-blooded and haemoglobinless fish: undetectable metallothionein levels in haemoglobinless fish is accompanied by accumulation of untranslated metallothionein mRNA
Radiazione adattativa dei pesci antartici. Mappatura in situ di tratti evolutivamente rilevanti nel genoma dei Notothenioidei (IMAGES).
Notothenioid fish are the result of adaptive radiation in the Southern Ocean, during oceanographic and
ecological changes driven by the tectonics of the Antarctic continent. Remarkable biological and ecological
modifications underlie the diversification and the evolutionary success of these fishes, presently recognized
as prominent models in evolutionary/adaptive studies.
In present project we will integrate sequence-based data from the available genomic resources with
powerful in situ technologies, to provide patterns of genome structure and change in notothenioids over an
evolutionary time scale. This will be achieved by physical mapping, onto the notothenioid chromosomal
genomes, of marker sequences selected for their high informative value (AFGPs genes, sex-related
sequences, iron metabolism genes, LINE sequences).
The research aims at providing an comparative picture of the genome structure across notothenioid
phylogeny to contribute to elucidate steps and mechanisms of genomic restructuring in this important animal
model, over evolutionary time scale. The research contributes to the ongoing international effort towards our
understanding of patterns and mechanisms of biological response to environmental change
Unexpected Diversity of Metallothionein Primary Structure in Amphibians: Evolutionary Implications for Vertebrate Metallothioneins.
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