Biology subjects

Jung, M. M.

Publications and source records attributed to Jung, M. M..

5 recordsLinked to original sources

bioRxiv2025

Maternal sucrose intake during pregnancy alone disrupts testosterone and allopregnanolone levels in the fetal brain of rats

BackgroundIntake of added sugars, such as sucrose, is high globally. In rats, a maternal high-sucrose diet (HSD) from 10 wk before pregnancy to embryonic day (E)19.5 has widespread impacts on maternal, placental, and fetal blood and brain steroid levels, including glucocorticoids, androgens, and aldosterone. ObjectiveThis study examined whether maternal HSD during pregnancy alone is sufficient to alter maternal, placental, and fetal steroids. MethodsPregnant rats received either a control diet (1% kcal sucrose) or an isocaloric, nutrient-matched HSD (26% kcal sucrose) between E0.5-19.5. On E19.5, we collected maternal serum, placenta, fetal blood and brain, and amniotic fluid. We microdissected the placenta and fetal brain and measured 14 steroids using highly sensitive and specific liquid chromatography-tandem mass spectrometry (n=12-15/diet/sex). ResultsMaternal HSD during pregnancy alone did not alter maternal food intake, maternal body mass, and litter size (all p values [≥] 0.29, Students t-test) but increased the percentage of males in a litter (p = 0.03, Students t-test). Maternal HSD did not alter steroids in the maternal serum (all p values [≥] 0.21, Students t-test), placenta (all p values [≥] 0.07, 2-way analysis of variance (ANOVA)), and fetal blood (all p values [≥] 0.13, 2-way ANOVA). Nonetheless, maternal HSD increased testosterone in the fetal nucleus accumbens (p = 0.04, 2-way ANOVA), decreased allopregnanolone in the fetal amygdala (p = 0.01, 2-way ANOVA), and decreased 11-dehydrocorticosterone in the amniotic fluid (p = 0.05, 2-way ANOVA). ConclusionsMaternal HSD during pregnancy alone does not affect steroid levels in the maternal serum, placenta, or fetal blood, but disrupts testosterone and allopregnanolone levels in critical regions of the fetal brain that regulate reward-seeking and emotion. Thus, while a long-term maternal HSD is necessary for widespread endocrine effects, the fetal brain is sensitive to short-term increases in maternal sucrose consumption during pregnancy.

neuroscience↗

bioRxiv2024

Amphiphile-engineered DNA adjuvants stimulate strong type I IFN production in lymph nodes via cytosolic danger-sensing to induce potent cellular and humoral immunity in mice and non-human primates

Adjuvants are immuno-activators capable of shaping the magnitude and quality of antigen-specific immune responses induced by subunit immunization. Presently, there is an acute need for effective adjuvants that safely induce durable and balanced humoral and cellular responses; the latter being indispensable for protection against intracellular pathogens and cancer. Here, we iteratively optimized a novel class of Amphiphile (AMP)-modified, immunostimulatory DNA-adjuvants designed for targeted delivery to lymph nodes and enhanced stimulation of cytosolic danger-sensing pathways to generate strong adaptive immunity. AMP-DNA adjuvants induced potent IFN-I-driven inflammatory environments in mouse and NHP lymph nodes that were dependent on TBK1 signaling, leading to significantly enhanced cytokine secretion by polyfunctional CD8+ and CD4+ T cells in multiple tissues, and strongly elevated TH1-associated and neutralizing antibody responses, without toxicity. These results demonstrate that AMP-engineering enables lymph node-targeted DNA-adjuvants to uniquely activate cytosolic immune-signaling to generate robust adaptive responses crucial for vaccine efficacy.

immunology↗

bioRxiv2024

Prenatal glyphosate exposure disrupts the gut-brain axis across several generations in mice.

Glyphosate, a widely used herbicide in North America, has become prevalent in the food supply, raising concerns about potential health impacts. In this exploratory study, male and female F0 mice were exposed to glyphosate through drinking water during mating and gestation. We investigated whether prenatal exposure at dietary-relevant levels (0.01 mg/kg/day, Average American Diet, [AAD]) or the U.S. EPAs acceptable daily intake (1.75 mg/kg/day, [EPA upper limit]) altered gut, metabolic, and behavioral outcomes across two generations in mice with or without genetic susceptibility to colitis (Muc2+/- and Muc2-/-, respectively). Healthy (Muc2+/-) offspring of glyphosate-exposed mice exhibited colonic goblet cell depletion, reduced mucin-2 expression, and pro-inflammatory cytokine profiles in both F1 and F2 generations. These healthy (Muc2+/-) offspring also developed metabolic dysfunction, including impaired glucose tolerance, insulin resistance, and reduced GLP-1 in serum. Behavioral deficits were also observed in healthy (Muc+/-) mice including reduced locomotion and working memory, and these changes were associated with altered microbiome composition and gut-brain mediators. These findings suggest that prenatal glyphosate exposure, even below regulatory thresholds, may disrupt multiple physiological systems across generations, highlighting the need for further research and regulatory consideration.

pharmacology and toxicology↗

bioRxiv2023

Maternal high-sucrose consumption increases maternal and fetal glucocorticoids and decreases fetal androgens in the rat

Maternal diet has long-term effects on offspring brain development and behavior. Sucrose (table sugar) intakes are high in modern diets, but it is not clear how a maternal high-sucrose diet (HSD) affects the offspring. In rats, a maternal HSD (26% of calories from sucrose, which is human-relevant) alters maternal metabolism and brain and also alters adult offspring endocrinology and behavior in a sex-specific manner. Maternal sucrose intake increases corticosterone levels in adult female offspring and increases motivation for a sugar reward in adult male offspring. Here, to identify possible underlying mechanisms, we examined how a maternal HSD affects steroids in the dam, placenta, and fetus at embryonic day 19.5 using liquid chromatography tandem mass spectrometry. Maternal sucrose intake increased glucocorticoids (11-deoxycorticosterone and 11-dehydrocorticosterone) and tended to increase the mineralocorticoid aldosterone in maternal serum. In the placenta, maternal sucrose intake decreased androstenedione and testosterone. Maternal HSD increased aldosterone in the fetal blood. Similarly, in the fetal brain, maternal high-sucrose intake increased aldosterone in the medial prefrontal cortex and nucleus accumbens, decreased testosterone in the nucleus accumbens, and decreased corticosterone in the orbital cortex. In addition, the 11-dehydrocorticosterone/corticosterone and aldosterone/corticosterone ratios were increased in most examined brain regions. Lastly, maternal HSD increased 11-dehydrocorticosterone and aldosterone in the amniotic fluid. In summary, we found dramatic and widespread changes in maternal, placental, and fetal steroids that might mediate the long-term effects of maternal sucrose consumption on adult offspring neuroendocrinology and behavior.

neuroscience↗

bioRxiv2021

Competition Between Cell-Cell and Cell-Substrate Adhesion Determines Epithelial Monolayer Architecture in Culture

Organ surfaces are lined by epithelial monolayers - sheets of cells that are one-cell thick. This architecture underlies tissue function, and its loss is associated with disease, including cancer. Studies of in-plane epithelial cell behaviors show that a developing epithelium behaves as a fluid in respect to the tissue plane, and can therefore readily adapt to varying mechanical influences during morphogenesis. We asked the question of how monolayer architecture is achieved, and whether it demonstrates the same fluid behavior. To address this problem, we cultured MDCK (Madin-Darby Canine Kidney) cell layers at different densities and timepoints and analyzed their architectures using a novel tool, Automated Layer Analysis (ALAn), which we introduce here. Our experimental and theoretical results lead us to propose that epithelial monolayer architecture is governed by a balance of counteracting forces due to cell-cell and cell-substrate adhesion, and that this balance is influenced by cell density. MDCK cells do not undergo obvious rearrangement along the apical-basal axis; instead, cells that do not contact the substrate aggregate on top of the monolayer. Our findings therefore imply that monolayered architecture is under more rigid control than planar tissue shape in epithelia.

cell biology↗