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Biology subjects

Ramirez, A. V.

Publications and source records attributed to Ramirez, A. V..

3 recordsLinked to original sources

Tear Proteomics Reveals RAGE and NLRP3 Inflammasome Pathway Activation in Lacrimal Glands of a Sjögren's Disease Mouse Model

PurposeTo characterize tear proteome changes in male non-obese diabetic (NOD) mice with Sjogrens disease (SjD)-like autoimmune dacryoadenitis and determine whether identified tear proteins are associated with lacrimal gland (LG) pathogenesis. MethodsTears were collected from 14-week-old male NOD mice and age-matched male BALB/c controls and analyzed by tandem mass tag (TMT)-based liquid chromatography tandem mass spectrometry (LC-MS/MS). Differentially expressed proteins (DEPs) were defined using adjusted P < 0.05 and absolute fold change > 1.5. Functional enrichment analysis was performed using Enrichr. Selected upregulated DEPs were further examined in tear and LG samples from independent mouse cohorts using Western blotting, immunofluorescence, and RT-qPCR. ResultsA total of 142 proteins were quantified across all tear samples. Hierarchical clustering and principal component analysis (PCA) separated NOD from BALB/c tear proteomes. A total of 41 proteins were differentially expressed in NOD mouse tears (33 increased, 8 decreased). Increased tear proteins were enriched in immune and inflammatory responses, secretory compartments, RAGE receptor binding, glutathione metabolism, oxidative stress, and redox regulation. S100A8/A9, GSTO1-1, Gal-3, and pIgR/secretory component (SC) were increased in both NOD mouse tears and LG. In NOD LG, increased S100A8/A9 was accompanied by elevated RAGE, whereas increased GSTO1-1 was associated with increased NLRP3, cleaved caspase-1, cleaved gasdermin, cleaved IL-1{beta}, and increased Il1b, Il18, and Il18r gene expression. ConclusionsMale NOD mouse tears contain disease-related proteins reflecting pathological inflammatory and epithelial changes in the LG including increased RAGE signaling, NLRP3 inflammasome activation, and altered epithelial transcytosis.

immunology↗

Sex differences in responses to aggressive encounters among California mice

Despite how widespread female aggression is across the animal kingdom, there remains much unknown about its neuroendocrine mechanisms, especially in females that engage in aggression outside the peripartum period. Although the impact of experience in aggressive encounters on steroid hormone responses have been described, little is known about the impact of these experiences on female behavior or their neuropeptide responses. In this study, we compared behavioral responses in both male and female adult California mice based on if they had 0, 1, or 3 aggressive encounters using a modified resident intruder paradigm. We measured how arginine vasopressin and oxytocin cells in the paraventricular nucleus responded to aggression using c-fos immunohistochemistry. We saw that both sexes disengaged with intruders with repeated aggressive encounters, but that on the final day of testing females were most likely to freeze when they encountered intruders compared to no aggression controls - which was not significant in males. Finally, we saw that percent of arginine vasopressin and c-fos co-localizations in the posterior region of the paraventricular nucleus increased in males who fought compared to no aggression controls. No difference was observed in females. Overall, there is evidence that engaging in aggression induces stress responses in both sexes, and that females may be more sensitive to the effects of fighting.

neuroscience↗

INPP5D limits plaque formation and glial reactivity in the APP/PS1 mouse model of Alzheimer's disease

The dual specificity lipid/protein phosphatase SHIP1 (encoded by the INPP5D gene) is enriched in myeloid cells. Single nucleotide polymorphisms (SNPs) in INPP5D coding and non-coding regions impact risk for developing late onset sporadic Alzheimers disease (LOAD). We present pathological analyses with spatial transcriptomics of mice with tamoxifen-sensitive microglial knockdown of Inpp5d and show exacerbated plaque pathology, plaque-associated microglial density, and altered gene expression around plaques, suggesting novel markers for plaque-associated reactive microglia.

neuroscience↗