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Biology subjects

Perez-Fernandez, C.

Publications and source records attributed to Perez-Fernandez, C..

4 recordsLinked to original sources

Is Probiotic Supplementation During Pregnancy Safe for Healthy Populations? A Systematic Review of Preclinical Studies

Gut-brain axis and probiotics supplementation during gestational period have gained an especial attention in the field of neurodevelopmental disorders. However, the influence of prenatal probiotics in physiology and neurodevelopment of healthy organisms is widely unexplored and probiotics are commercially such as dietetic supplementations without the necessity of ensuring safety in healthy organisms, as is required for drugs. The aim is to present and discuss the various biochemical, developmental and behavioral effects that prenatal probiotics have on the offspring of healthy organisms in rodent models and assess their security during gestation. We included a total of 15 preclinical studies discarding all those that did not have an appropriate control for the probiotic-treated group. Results suggest that probiotics, particularly Lactobacillus strains, influenced anxiety-like behaviors in mice and GABAergic system maturation, showing an apparent biphasic effect, reducing GABA functioning in early life but increasing them in later stages; and both prenatal Lactobacillus and Bifidobacterium, influenced microbiota and general development of healthy organisms. However, the significant variations in methodologies used across studies complicate the ability to elucidate specific conclusions related to bacterial strains or doses. Further research is imperative to ensure the safety and regulation of probiotic interventions, particularly during the gestational period.

developmental biology↗

Modulating Neurotoxic Effects of Prenatal Chlorpyrifos Exposure Through Probiotic and Vitamin D Gestational Supplementation: Unexpected Effects on Neurodevelopment and Sociability

Autism is a neurodevelopmental disorder characterized by impairments in sociability and communication. Prenatal exposure to Chlorpyrifos has been associated with autism-like behaviors in preclinical models. Interest has grown in the gut-brain axis and the role of microbiota modulation through dietetic supplementation to reduce this ASD-like phenotype. This study examines the effects of prenatal CPF exposure in Wistar Rats and assesses the potential of gestational probiotic and vitamin D supplementation to mitigate these effects in offspring. CPF exposure significantly impaired sociability in adolescence, and supplementation did not reverse these deficits. However, in control animals, supplementation induced neurodevelopmental changes, including alterations in metabolic status, the pattern of expression of ASD-related genes, the regulation of oxytocin and vasopressin receptors, and the GABAergic system in the brain. Additionally, supplementation accelerated overall development, increased ultrasonic vocalization emission and modified the typical responses to social novelty. CPF exposure blocked most of these effects at both behavioral and molecular levels. While supplementation did not block CPF-induced impairments, CPF exposure altered the observed effects of supplementation in controls, possibly indicating shared molecular mechanisms. These findings highlight the need for further research into the safety of probiotic and vitamin D supplementation during pregnancy.

neuroscience↗

Adaptation of cyanobacteria to the endolithic light spectrum in hyper-arid deserts

In hyper-arid deserts, endolithic microbial communities survive in the pore spaces and cracks of rocks, an environment that enhances water retention and filters UV radiation. The rock colonization zone is enriched in far-red light (FRL) and depleted in visible light. This poses a challenge to cyanobacteria, which are the primary producers of endolithic communities. Many species of cyanobacteria are capable of Far-Red Light Photoacclimation (FaRLiP), a process in which FRL induces the synthesis of specialized chlorophylls and remodeling of the photosynthetic apparatus, providing the ability to grow in FRL. While FaRLiP has been reported in cyanobacteria from various low-light environments, our understanding of light adaptations for endolithic cyanobacteria remains limited. Here, we demonstrated that endolithic Chroococidiopsis isolates from deserts around the world synthesize chlorophyll f, an FRL-specialized chlorophyll when FRL is the sole light source. The metagenome-assembled genomes of these isolates encoded chlorophyll f synthase and all the genes required to implement the FaRLiP response. We also present evidence of FRL-induced changes to the major light-harvesting complexes of a Chroococidiopsis isolate. These findings indicate that endolithic cyanobacteria from hyper-arid deserts use FRL photo-acclimation as an adaptation to the unique light transmission spectrum of their rocky habitat.

microbiology↗

Adaptations of endolithic communities to abrupt environmental changes in a hyper-arid desert

The adaptation mechanisms of microbial communities to natural perturbations remain relatively unexplored, particularly in extreme environments. The extremophilic communities of halite (NaCl) nodules from the hyper-arid core of the Atacama Desert are self-sustained and represent a unique opportunity to study functional adaptations and community dynamics with changing environmental conditions. We transplanted halite nodules to different sites in the desert and investigated how their taxonomic, cellular, and biochemical changes correlated with water availability, using environmental data modeling and metagenomic analyses. Salt-in strategists, mainly represented by haloarchaea, significantly increased in relative abundance at sites characterized by extreme dryness, multiple wet/dry cycles, and colder conditions. The functional analysis of metagenome-assembled genomes (MAGs) revealed site-specific enrichments in archaeal MAGs encoding for the uptake of various compatible solutes and for glycerol utilization. These findings suggest that opportunistic salt-in strategists took over the halite communities at the driest sites. They most likely benefited from metabolites newly released in the environment by the death of microorganisms least adapted to the new conditions. The observed changes were consistent with the need to maximize cellular bioenergetics when confronted with lower water availability and higher salinity, providing valuable information on microbial community adaptations and resilience to climate change.

microbiology↗