Biology subjects

Pessoni, A. M.

Publications and source records attributed to Pessoni, A. M..

4 recordsLinked to original sources

bioRxiv2024

Transcriptional profiling of the cortico-accumbal pathway reveals sex-specific alterations underlying stress susceptibility

Anxiety and depressive disorders, including major depressive disorder (MDD), affect millions of people every year, imposing significant socio-economic burdens. In this scenario, current treatments for MDD show limited efficacy, highlighting the need to better understand its molecular mechanisms. The medial prefrontal cortex (mPFC) has been identified as a critical brain region in MDD pathology, displaying altered activity and morphology. This study targets the mPFC-to-nucleus accumbens (NAc) pathway, which is implicated in the regulation of emotional behavior. We used a pathway-specific approach to uncover transcriptional profiles in mPFC neurons projecting to the NAc in stressed male and female mice. Using the RiboTag technique and RNA sequencing, we identified sex-specific gene expression changes, revealing potential roles in stress susceptibility. Differential expression and weighted gene co-expression network analyses revealed distinct transcriptional responses to chronic stress in males and females. Key findings include the identification of the X-linked lymphocyte-regulated 4B (Xlr4b) gene, within a highly relevant gene module, as a stress susceptibility driver in males. By experimentally overexpressing the Xlr4b gene, we characterized its crucial role in regulating neuronal firing and influencing arborization patterns to promote anxiety-like behavior in a sex-specific fashion. These findings suggest that chronic stress induces unique and shared transcriptional alterations in mPFC neurons projecting to the NAc. Some of these alterations change the morphological and functional properties of neuronal pathways ultimately contributing to the differential manifestation of anxiety-like and depressive-like behaviors in male and female mice.

neuroscience↗

bioRxiv2024

Deciphering Cargo Contents in Extracellular Vesicles of Candida haemulonii var. vulnera

ABSTRACTCandida haemulonii comprises a group of pathogenic fungi known for their resistance to primary antifungal treatments. Infections caused by these pathogens present substantial challenges due to the difficulties in accurate identification. Extracellular vesicles (EVs) released by these fungi play a critical role in the pathogen-host interaction, potentially influencing antifungal resistance and virulence. Previous research by our group indicates that EVs contain immunogenic particles capable of impacting the hosts immune response. Understanding the composition of these EVs is crucial for elucidating the mechanisms underlying resistance and virulence in C. haemulonii var. vulnera. This study aims to investigate the contents of EVs from C. haemulonii var. vulnera using proteomic and microRNA sequencing tools, providing insights into their role in adaptation, survival, and the progression of infections. Our findings reveal key proteins transported by EVs, including BMH1, TEF1, CDC19, and PDC11. These proteins are involved in various cellular processes, such as the alteration of cell wall structure, biofilm formation, and facilitation of morphological changes, among others. Additionally, we observed that miRNA-like molecules transported within EVs are linked to the electron transport chain and regulation of the citric acid cycle, which are metabolic processes associated with virulence factors and rapid adaptation to diverse hosts or environments. In this context, our findings provide a novel perspective on fungal EVs, highlighting their potential as targets for therapies. Therefore, these vesicles may reflect the expression levels of regulatory molecules crucial for the survival, pathogenicity, and virulence of C. haemulonii var. vulnera. IMPORTANCEThe study of Candida haemulonii complex holds substantial clinical significance due to its notable resistance to conventional antifungal therapies and the complex challenges inherent in its specific identification. This research focuses on cargo of EVs released by these fungi, which play an essential role in pathogen-host interactions, influencing fungal pathogenicity. EVs contain immunogenic particles that can modulate the hosts immune response. Proteomic and microRNA analyses of EVs from Candida haemulonii var. vulnera have identified key proteins and miRNAs involved in cellular processes such as metabolic adjustment, biofilm formation, and modulation of cytoplasmic functions. These components are essential for the adaptation, survival, and progression of infections. This study offers novel insights into fungal EVs, underscoring their potential as targets for therapeutic intervention. By elucidating the mechanisms underlying the rapid adaptation of Candida haemulonii, the research enhances our understanding of the pathogenicity of this emerging yeast.

microbiology↗

bioRxiv2023

Transcriptional dissection of symptomatic profiles across the brain of men and women with depression

Major depressive disorder (MDD) is one of the most important causes of disability worldwide. While recent work provides insights into the molecular alterations in the brain of patients with MDD, whether these molecular signatures can be associated with the expression of specific symptom domains in males and females remains unclear. Here, we identified sex-specific gene modules associated with the expression of MDD, combining differential gene expression and co-expression network analyses in six cortical and subcortical brain regions. Our results show varying levels of network homology between males and females across brain regions, although the association between these structures and the expression of MDD remains highly sex-specific. We refined these associations to several symptom domains and identified transcriptional signatures associated with distinct functional pathways, including GABAergic and glutamatergic neurotransmission, metabolic processes, and intracellular signal transduction, across brain regions associated with distinct symptomatic profiles in a sex-specific fashion. In most cases, these associations were specific to males or to females with MDD, although a subset of gene modules associated with common symptomatic features in both sexes was also identified. Together, our findings suggest that the expression of distinct MDD symptom domains is associated with sex-specific transcriptional structures across brain regions.

neuroscience↗

bioRxiv2021

Fungal extracellular vesicles are involved in intraspecies intracellular communication

Fungal infections are associated with high mortality rates in humans. The risk of fungal diseases creates the urgent need to broaden the knowledge base regarding their pathophysiology. In this sense, the role of extracellular vesicles (EVs) has been described to convey biological information and participate in the fungal-host interaction process. EVs play many roles, including cellular physiology, responding to environmental cues, mediating a complex circuit of cellular communication in bidirectional crosstalk with other organisms, and the communication between fungal cells has been speculated. This study demonstrated the intra species uptake of EVs in fungi, including Candida albicans, Aspergillus fumigatus, and Paracoccidioides brasiliensis, and the effects triggered by EVs in fungal cells. In C. albicans, we evaluated the involvement of EVs in yeast to hyphae transition, whilst in P. brasiliensis and A. fumigatus the function of EVs as stress transducers was investigated. Both P. brasiliensis and A. fumigatus were exposed to an inhibitor of glycosylation or UV light, respectively. The results demonstrated the role of EVs in regulating the expression of target genes and phenotype features. The EVs treatment induced cellular proliferation and boosted the transition yeast to hyphal transition in C. albicans, while they enhanced stress signals in A. fumigatus and P. brasiliensis, establishing a role for EVs in fungal intra species communication. Thus, fungal EVs regulate the virulence and adaptive traits in fungal interaction systems as potent message effectors, and understanding their effects and mechanism(s) of action could be exploited in antifungal therapies. Author SummaryExtracellular vesicles (EVs) play an important role in export systems. They act as vehicles for the transference of complex cargoes with broad biological functions, such as proteins, carbohydrates, pigments, nucleic acids, and lipids. EVs can contribute to fungal infection outcomes. The EV content exerts immunomodulatory functions during fungus-host interactions. Furthermore, the participation of EVs in communication between fungal cells has been speculated. This study investigated the capacity of EVs to mediate intra-species in three genera of human pathogenic fungi and established a regulatory function of EVs. We also assessed the features of this regulation by analyzing the cellular morphological aspects of fungi after stimulation with EVs. Our data suggest fungal EVs can function as potent signal mediators that mediate virulence and adaptive responses.

microbiology↗