Dipartimento di Biologia, Ecologia e Scienze della Terra - Tesi di dottorato
Permanent URI for this collectionhttps://lisa.unical.it/handle/10955/34
Questa collezione raccoglie le Tesi di Dottorato afferenti al Dipartimento Dipartimento di Biologia, Ecologia e Scienze della Terra dell'Università della Calabria.
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Item Late pleistocene coastal sea surface temperature and environmental reconstruction for a post global-warming climate modelling in the central mediterranean(Università della Calabria, 2024-07-30) Santagati, Pierluigi; Critelli, Salvatore; Perri, Edoardo; Bernaconi, aria PiaThe Last Interglacial (MIS 5) is a warm period within the Late Pleistocene. In particular, its first substage (MIS 5e) is the last warmer than today period before the present-day Interglacial, therefore it is considered a good analogue for assessing future climate responses to global warming. The present work focuses on two shallow marine deposits cropping out along the Ionian Sea coastline, central Mediterranean: 1) a MIS 5e fossiliferous calcarenite from Taranto (Apulia), and 2) MIS 5a/c bioconstructed deposits from Capo Colonna (Calabria). These deposits were studied for a paleoenvironmental characterization, which included the paleoecology of benthic associations, paleotemperature estimates and early diagenetic phenomena, with the aim of providing new data on the response of these systems to climatic variations. The MIS 5e calcarenite from Taranto, sampled in three related sites cropping out along the Mar Piccolo (MP) coastline (Masseria La Penna, Mass. S. Pietro, and Il Fronte), returned a rich molluscan fauna consisting of 120 extant species and 5174 individuals, including four of the tropical Senegalese Fauna, today absent in the Mediterranean. The molluscan assemblages were used for a refined quantitative palaeoenvironmental reconstruction; as a whole, the fauna represents an autochthonous-parautochthonous assemblage coming from a sandy-vegetated infralittoral bottom, locally accompanied by coarser and less finer sediment fractions, and characterized by slight lateral variability, shifting from more sheltered and exposed areas, and from finer and coarser bottoms, suggesting a heterogeneous and well-structured palaeoenvironment during MIS 5e. The same molluscan assemblage was used for a multi-proxy palaeoclimatic study. The biogeographic-climatic affinity of the assemblage shows, compared to today, a double percentage of warm affinity species, while the cold affinity species are similarly represented, indicating a warmer but not strictly tropical Sea Surface Temperature (SST). This is confirmed by the most recurring preferred SST ranges of the assemblage, indicating an average of 20 °C. The skeletal compositions of five well-preserved molluscan and coral specimens were analyzed for trace elements and stable isotopes for further mean SST estimations. From the comparison of the results of several equations available in literature, it appears that only some SST estimations are realistic, converging into similar values of, on average, 20.8 ± 0.9 °C. Considering all the used proxies, the MIS 5e SST difference compared to today falls in the range 1.2 - 2.0 °C for the Gulf of Taranto (GT) (being a more reasonable scenario) and 2.0 - 2.8 °C for the MP. This is not a firmly tropical-like SST setting as suggested by the sole Senegalese fauna, indicating at least 2.7 °C to 3.5 °C more than to today’s GT and MP, respectively. The approximations and assumptions made for obtaining SST values with any single proxy indicates the need of a multi-proxy approach to define the best SST estimation. Cemented samples of the same MIS 5e calcarenite were analyzed through optical and SEM analyses. Clasts mostly consist in medium to coarse sandy size skeletons and fragments of skeletons of a variegated biota together with mainly large mollusks shells that inhabited the sediment and a very minor amount of siliciclastic. Micritization variably affects most of the bioclasts while cements are constituted by a microcrystalline texture with various micro-morphologies and fabrics: not-isopachous aphanitic and filamentous rims, vacuolar peloidal meniscus, aphanitic micro-mounds, and aphanitic porosity-filling matrix. Cements are constituted by sub-micron sized anhedral to nanospheroidal crystals of low Mg calcite, mixed with a minor amount of irregular platy crystals of saponite. All fabrics of cement are rich of mineralized filamentous, tubular, and sub-spherical bacteria bodies that imply the presence of a microbial community forming an epilithic to endolithic biofilm that stabilized the incoherent sediment and mediated the early precipitation of cements. This process led to the synsedimentary hardening of some parts the mobile sandy substrate, allowing the settlement of sessile taxa - such as Spondylus gaederopus, oysters, serpulids and barnacles. The Last Interglacial (MIS 5) transgressive-regressive deposits of the Capo Colonna marine terrace provide a good fossil example of a Central Mediterranean infra/circa-littoral setting, characterized by both calcareous coralline algae-dominated low-relief bioherms and biostromes, analogous respectively to the present coralligenous and mäerl habitats. The skeletal primary framework of the bioherms consists of laminar to massive encrusting coralline red algae acting as main bioconstructors, with minor bryozoans, encrusting foraminifera and serpulids as secondary frame-builders. Whereas the autochthonous mäerl tabular beds are mainly composed of free-branched coralline red algae rudstones. A variable amount of sandy bioclastic sediment is laterally interbedded with the bioconstructions and tends to be entrapped in their cavities and pockets. All sedimentary sub-facies of the bioconstructions and associated sediment, are rich in autochthonous syn-sedimentary microbial-mediated micrite, forming aphanitic, peloidal, clotted peloidal, and filamentous fabrics. Microbial micrite can also trap and bind a variable amount of grains or being a secondary component of the sandy detrital sediment with micritic rims surrounding the clasts. All these early-lithified micrites show the typical nanostructure of the primary microbial-mediated carbonates, rather than a detrital mud particles accumulation, as they consist of nanospheres coalescing into subhedral microcrystals, replacing, and mineralizing both microbial cells (present with several morphological types) and extracellular substances. This in turn implies the widespread presence of benthic lithifying microbial biofilms that colonized both the cavities of the skeletal framework of the bioconstructions, and the intergranular space of the associated sediment. These microbial communities, thanks to the metabolic processes of the microorganisms that induced the carbonate precipitation, significantly contributed to the early cementation of all the studied deposits. In conclusion, the results of the work were used to infer possible effects of climate change in similar Mediterranean contexts. The diversity and temperature preferences of the MIS 5e molluscan assemblage from Taranto show no significant differences compared to modern analogous faunas from some Southern Italy sites reported in the literature, which could show a resilient response to an SST increase of +2 °C, already experienced during MIS 5e and expected in the next decades. This, however, does not consider the different causes, the current higher warming rates, as well as the human impact, which could affect faunas more than the temperature itself. Today, microbial induced micritic cementation processes, similar to those reported in the studied MIS 5 deposits, are observed in tropical/subtropical carbonate platform realms and have not been indicated for similar infra-circalittoral beds of the modern Mediterranean. Their occurrence in MIS 5 deposits confirms the warmer SST during MIS 5e and suggests a persistently warm SST at the end of MIS 5. However, as these cements have been associated with an estimated SST of just +2 °C compared to modern times, it is suggested that early cementation could become common in the Mediterranean mobile bottoms already in the near future as an effect of the global warming.Item Identification of epigenetic mechanisms involved in seed coat development(Università della Calabria, 2024-04-29) Talarico, Emanuela; Angelone, Tommaso; Bruno, LeonardoThe evolution of seeds is a fascinating aspect of evolutionary history and plant biology. Seeds have evolved over millions of years and are considered a significant adaptation that has contributed to the success of land plants. Seeds provide protection and a means of dispersal, enabling plants to reproduce successfully in a wide range of conditions. This evolutionary history has led to the rich diversity of plant species we see on Earth today. Seeds show remarkable adaptations to survive long journeys, including different shapes, sizes and mechanisms for dispersal. But none of these features would have been possible without the evolution of the ovule, within which sexual reproduction occurs. Indeed, ovule is the structure in which take place the formation of female gametophyte, fertilisation, embryogenesis and seed development upon fertilisation. In this scenario, the aim of this Ph. D. project was to identify, at evolutionary level, the molecular and epigenetic mechanisms involved in the ovule-to-seed switch in Ginkgo biloba plants. In particular, the focus was only on the pollination event, which in such a system is separated from fertilisation by a long time interval (i.e. four/five months). Indeed, Ginkgo biloba, a member of the gymnosperms and the only extant species of the order Ginkgoales, was used as experimental model because it is considered a living fossil due to its very ancient origins, dating back to the Permian period, the last period of the Palaeozoic, when an integument developed for the first time to cover the megasporangium. An interesting characteristic of Ginkgo, which makes it suitable for this purpose, is the production of fleshy fruit-like structures that are attractive to animals. Indeed, already after pollination, the integument takes on a consistency similar to that of mesocarp of fleshy fruit, leading to the hypothesis that it may represent a precursor to the fruit, although it cannot be identified as such because gymnosperms lack an ovary. Various approaches, including RNA sequencing, in situ gene expression, hormones localization and chromatin immunoprecipitation following by sequencing (ChIP-seq), on ovules at different stages were performed in order to identify the key pathways and the epigenetically regulated genes involved in ovule-seed switch. In order to identify the main pathways modulated by the crucial pollination event, three developmental stages of the Ginkgo ovule, collected immediately after the time frame in which pollination drop emission occurs, were used. In this context, pollination drop emission is an interesting aspect because, in many gymnosperms, it identifies the time point of possible pollen reception. Therefore, samples were collected from two different experimental fields, the first characterised by the presence of both male and female plants, and the second where only female plants are present. The two experimental fields are geographically distant from each other, which means that the plants in the second field are unable to receive pollen, so they are useful for understanding how ovule development proceeds in the absence of the pollination event. Moreover, this Ph. D. thesis was part of a larger project, which involved collaboration with the research groups coordinated by Professor Barbara Baldan, University of Padua, and Professor Lucia Colombo, University of Milan, helping to produce a large amount of data on Ginkgo, but also on Arabidopsis, which has always been the model species in plant biology. With the contribution also of the results we produced, it was possible to compare the two species and describe some of the key genes involved in ovule development in Ginkgo. Finally, most of the bioinformatic analyses related to the ChIP-seq experiment reported in this thesis were performed in collaboration with Professor Ernesto Picardi of the University of Bari Aldo Moro and Dr. Antonella Muto, post-doc in my research group at the University of Calabria.Item Valorizzazione del Sargasso per la produzione di biometano in Repubblica Dominicana(Università della Calabria, 2024-05-07) Paletta, Rosy; Angelone, Tommaso; Calabrò, Vincenza; Arcuri, NataleItem RHEOLOGICAL STUDY OF BITUMINOUS ECOBASES FOR COLD RECYCLING(Università della Calabria, 2024-06-26) Marchesano, Ylenia Maria; Angelone, Tommaso; Baldino, Noemi; Gabriele, DomenicoThe environmental benefits of reduced toxic emissions, energy and economic savings, fewer and faster traffic disruptions, and increased safety for pavement operators make cold recycling pavement technologies far more advantageous than conventional reconstruction strategies. The recycling of asphalt mixes is therefore fundamental to a proper policy of natural resource conservation and "integrated" environmental design. Ecobases are an excellent cold recycling method because they allow the recycling of existing pavements, i.e. RAP, to be combined with the use of bituminous technology formulations, such as bituminous emulsions. Primarily composed of a bituminous and aqueous phase, these materials are undergoing ongoing research and development to enhance their mechanical performance, aiming to surpass that of traditional hot mix pavements. In addition, several studies, including this PhD thesis, are focused on identifying more environmentally friendly surfactants and achieving a higher pH for emulsion stability by using less acid and making the emulsion more stable, as well as on the identification of fillers capable of replacing those currently used, such as cement, which only provide stiffness, with substances capable of providing load-bearing capacity and flexibility at the same time, to resist the loads that road pavements must withstand today To this end, interfacial techniques have been demonstrated to be crucial. Interfacial instruments can measure the surfactant power of substances through interfacial tensions and therefore their ability to create emulsions. The -potential measurements and the observation in cylinders of the emulsions were fundamental for stability monitoring and were consistent with both the interfacial and bulk tests.Item Aspetti neurocomportamentali e possibili approcci terapeutici del Disturbo dello Spettro Autistico nel modello roditore BTBR T+Itpr3tf/J (BTBR)(Università della Calabria, 2024-04-29) Olivito, Ilaria; Angelone, Tommaso; Facciolo, Rosa MariaAutism Spectrum Disorder (ASD) is a complex neurodevelopmental syndrome characterized by a diverse range of clinical manifestations, encompassing social deficits and repetitive stereotypical behaviors. These symptoms often coexist with psychiatric and medical comorbidities, adding intricacy to the pathological profile of the disorder. The pervasive prevalence and enduring symptoms across the lifespan underscore the significant public health impact of ASD. However, the underlying pathophysiological mechanisms remain poorly understood, and there is a current lack of specific targeted medications. Given the intricate and heterogeneous nature of the symptomatology associated with this syndrome, the adoption of a multifaceted approach emerges as a valuable strategy to deepen the comprehension of its pathophysiology and advance more effective therapeutic interventions. Within these strategic considerations, inducing a ketogenic metabolic state presents a promising avenue, capable of mitigating abnormal behaviors while concurrently ameliorating psychological and sociological aspects across various neurological conditions. This approach operates through diverse molecular pathways, including the modulation of the gut microbiota, identified as a pivotal center for brain regulation. In the context of addressing these challenges, the current doctoral project aims to significantly contribute to the comprehension of ASD's pathophysiology. This is achieved through a comprehensive exploration of behavioral aspects, molecular dynamics, the association with the gut microbiota, and potential therapeutic strategies. Noteworthy is the adopted methodological approach, which involves analyzing the effects of ketosis in the BTBR rodent model of autism, encompassing both in vivo and in vitro assessments. This analysis includes evaluations of behavioral performance, key molecular mechanisms, and integration with the assessment of the gut microbiota. Results from an initial in vivo study demonstrated that the adoption of a ketogenic diet (KD) notably mitigated social deficit (p=0.002), repetitive behaviors (p<0.001), and memory impairments (p=0.001) in BTBR mice. These behavioral enhancements were associated with reduced levels of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β, and IL-6 in the plasma (p=0.007; p<0.001, and p=0.023, respectively), prefrontal cortex (PFC; p=0.006; p=0.04, and p=0.03), and hippocampus (HIP; p=0.02; p=0.09, and p=0.03). Furthermore, the KD mitigated oxidative stress, evidenced by modifications in lipid peroxidation levels (TBARS) and superoxide dismutase (SOD) activity in the brain areas of BTBR mice. Of particular interest, the KD positively influenced beneficial microbiota (Akkermansia and Blautia) and normalized aberrant levels of Lactobacillus in the feces of BTBR mice, underlining its neurophysiological impact through the modulation of the gut microbiota. The correlation between gut microbiota modulation and behavioral changes is substantiated by a meticulous analysis of the effects of five Lactobacillus strains in a study conducted during the planned abroad period within the doctoral project. This specific investigation unveiled a differential impact of the strains L. salivarius - LS7892, L. gasseri - LG6410, L. plantarum - LP14D, L. reuteri - LR92, and L. camelliae - LC LMG 24277 on social behavior, motor activity, and anxiety in BTBR mice. Particularly noteworthy, LS7892 emerged as a potential probiotic for ASD treatment among the examined strains. Following in vitro investigations revealed alterations in the cytoskeletal and synaptic organization in PFC and HIP neurons of BTBR, linked to fluctuations in Brain-Derived Neurotrophic Factor (BDNF) expression levels. The induction of a ketogenic state exhibited a beneficial modulation of the neural network, stabilizing compromised connections, and significantly increasing BDNF levels (p<0.001). In conclusion, the outcomes of this doctoral project underscore the significant relevance of the ketogenic approach and the modulation of the gut microbiota in the context of ASD. This research contributes to a more profound understanding of the pathophysiological foundations, offering innovative perspectives for the development of personalized and targeted therapeutic approaches.Item Dissecting the cross-talk between deregulated insulin/IGF axis and RAGE signaling in breast cancer(Università della Calabria, 2022-10-17) Muoio, Maria Grazia; Maggiolini, Marcello; De Francesco, ErnestinaItem The selenoprotein T-mimetic (PSELT) exerts cardiometabolic protection in rat and mouse models of obesity and metabolic syndrone(Università della Calabria, 2022-01-27) De Bartolo, Anna; Angelone, Tommaso; Giordano, Francesca; Anouar, YoussefItem Novel mechanisms involved by G-protein estrogen receptor (GPER) in the progression of Supervisore estrogen receptor-negative breast cancer(Università della Calabria, 2021-11-17) Talia, Marianna; Maggiolini, Marcello; Cerra, Maria CarmelaThe G protein-coupled estrogen receptor (GPER) is a seven transmembrane receptor that mediates estrogen signals in both normal and malignant cells, including breast cancer. In particular, GPER activation triggers diverse transduction pathways prompting transcriptional and biological pro-tumorigenic responses. In this context, we aimed to perform in-silico analysis that show a correlation of GPER expression levels with worse clinical-pathological features of breast cancer. By gene expression correlation, gene set enrichment analysis (GSEA) and KEGG pathway enrichment analysis on the transcriptomics data of ER-negative breast tumors provided by TCGA and METABRIC datasets, we also ascertained that the levels of GPER are associated with pro-migratory and metastatic genes. In particular, a strong association was found between the expression of GPER and that of genes belonging to cell adhesion molecules (CAMs), extracellular matrix (ECM)-receptor interaction and focal adhesion (FA) signaling pathways. Accordingly, we found that high GPER levels are predictive of a shorter disease-free interval (DFI) in ER-negative and HER2-negative breast cancer patients. Overall, our results may pave the way to further dissect the network triggered by GPER in breast malignancies lacking ER. Next, starting from a further bioinformatics analysis on TCGA and METABRIC triple negative breast cancer (TNBC) cohorts of patients, we determined that the expression of the pro-inflammatory cytokine interleukin-1β (IL-β) correlates with the levels of the hypoxia inducible factor-1α (HIF-1α) as well as with a hypoxia related gene signature. Then, through gene and protein expression studies, immunofluorescence analysis, co-immunoprecipitation, ChiP and ELISA assays we demonstrated that hypoxia triggers a functional liaison among HIF-1α, GPER and the IL-1β/IL1R1 signaling toward a metastatic gene signature and a feed-forward loop of IL-1β. Cell spreading, invasion and spheroid formation assays showed that IL-1β/IL1R1 axis leads to proliferative and invasive responses in TNBC cells. Furthermore, we found that the IL-1β released in the conditioned medium of TNBC cells exposed to hypoxic conditions promotes an invasive phenotype of breast cancer-associated fibroblasts (CAFs). Together, these findings may contribute to unveil the mechanisms involved in the hypoxic activation of the IL-1β/IL1R1 signaling toward aggressive features of both TNBC cells and CAFs, suggesting novel targets needed for innovative and more comprehensive therapeutic strategies in TNBC patients.Item Arm growth and regeneration in octopus (Octopus vulgaris and Eledone moschata)(Università della Calabria, 2020-02-12) Baldascino, Elena; Cerra, Maria Carmela; Fiorito, GrazianoHere I evaluated the timing and rate of arm regeneration in octopus, a cephalopod mollusc, and contributed to the understanding of the molecular machinery involved in arm growth and regeneration in two octopus’ species: Octopus vulgaris and Eledone moschata. This work stands and revisit in part the first experimental study on arm regeneration in cephalopod molluscs, including the two species carried out by M. Lange (1920). An arm of octopus may fully regenerate and regrowth in few months after amputation. Lange recognized three stages: wound healing, tissue degeneration and tissue renewal. I applied the 3Rs principle to this study utilizing samples and data from a previous study, thus limiting the number or live animals humanely killed for the purpose of this PhD project. During the analysis of data, I found the same three stages in O. vulgaris arm regeneration to occur. I was not able to observe similar series of events in E. moschata, probably due to limited time and conditions of the animals. I found that O. vulgaris increased significantly body weight in 21 weeks. The growth appeared to be affected by repeated anesthesia, thus encouraging further studies on the physiological responses to stress in octopus. Data I analyzed confirm the view that O. vulgaris is characterized by rapid non-asymptotic growth, with high individual variability. Octopuses elongate their arms continuing to grow over time with no significant difference in the relative rate of elongation between anterior and posterior arms. The arms that underwent to regeneration, appear to have a faster growth when compared with the contralateral arms (but repeated anesthesia influenced the rate of growth of regenerating arms). Data analyzed extent the study of Lange, by providing morphometric information on the relative growth rate of the arms (regenerating vs contralateral), for the first time. A significant change in the relative expression profile of the tip vs the proximal part of the arm in O. vulgaris was observed using different approaches, confirming and extending the view that the tip the arm represents an exceptional biological system where continuous growth is achieved through massive cellular differentiation and interesting molecular events. I identified 39 genes in O. vulgaris and seven in E. moschata and studied their involvement in arm growth and/or regeneration events in octopus arms. These studies are novel.Item Livelli fisiologici della Cromogranina A esercitano potente effetto cardioprotettivo contro la cardiotossicità indotta da doxorubicina(Università della Calabria, 2020-02-14) Granieri, Maria Concetta; Pasqua, Teresa; Angelone, TommasoThe clinical use of doxorubicin (Doxo), a widely used anticancer chemotherapeutic drug, is limited by dose-dependent cardiotoxicity. We have investigated whether chromogranin A (CgA), a cardioregulatory protein released in the blood by the neuroendocrine system and by the heart itself, may contribute to the regulation of cardiotoxic and antitumor activities of Doxo. We evaluated whether and to which extent, the in vivo administration of physiological doses of recombinant full-length CgA may exert cardioprotection in a Doxo-induced cardiotoxicity rat model and modulate the anticancer activity of Doxo in murine models of melanoma, fibrosarcoma, lymphoma, and lung cancer, respectively. The effect of Doxo on circulating levels of CgA was also investigated. At the end of the treatment, hearts were perfused by Langendorff method and Ischemic protocols were used. Western Blot, Immunohistochemistry techniques, and ELISA assay were used for molecular analysis and plasma measurements of TNFα, IL-1β, ROS, LDH, cTnT and CgA. We found that CgA mitigated Doxo-dependent adverse effects, as revealed by the reduction of pro-inflammatory and cardiotoxic markers. Doxo reduced CgA plasma levels. When given together with Doxo, CgA increased the systolic function after ischemia and reduced the infarct size, compared to the Doxo group alone. Molecular analysis indicated that CgA reduced CTGF expression, induced activation of the RISK and SAFE pathways and of AMPK, and reduced inflammatory targets such as iNOS, COX2, NLRP3. CgA reduced intracardiac ROS and the expression of AOX-1 and XO. CgA-dependent cardioprotection was mediated by ARC activation, by the increase of Bcl2 and the reduction of BAX, Caspase3 and the apoptotic nuclei. Furthermore, we observed that Doxo reduces the intracardiac expression and release of CgA (i.e., an important cardioprotective agent) in the blood. On the other hand, CgA did not impair the anticancer activity of Doxo in all the investigated murine models. These data suggest that CgA could mitigate Doxo-induced cardiotoxicity by limiting ischemic injury. The protein can be proposed as a possible biomarker and the administration of exogenous CgA to patients with low levels of the endogenous protein might represent a novel approach to prevent Doxo-induced adverse events without impairing its antitumor effects.