Anthropogenic Zinc Exposure Increases Mortality and Antioxidant Gene Expression in Monarch Butterflies with Low Access to Dietary Macronutrients

Environmental concentrations of cadmium and zinc and associating metabolomics profile alternations in urine of pregnant women in the first trimester: A prospective cohort study in Taiyuan, North China

especially to pregnant women. In recent years, zinc (Zn) supplementation has attracted increasing attention among pregnant women. Thus, understanding the effects and interactions of Cd and Zn in pregnant women is critical. This study aimed to assess the urinary levels of Cd and Zn in pregnant women during early pregnancy, examine associated alterations in urine metabolomics, and identify potential metabolic biomarkers among distinct Cd and Zn groups. Urine samples from 185 pregnant women were collected, and inductively coupled plasma mass spectrometry (ICP-MS) was used to detect Cd and Zn contents. The women were then divided into four groups according to median contents of Cd and Zn. Alterations in the metabolite profile were assessed using a liquid chromatograph mass spectrometer (LC-MS). The results showed that the gravidity of pregnant women was closely related to urinary Cd levels and that the urinary Zn contents of pregnant women with morning sickness in the first trimester were lower than that of non-morning-sick pregnant women. A total of 51 metabolites exhibited significant differential expression in the high level of Cd and Zn (HCdHZn) compared with low level of Cd and Zn (LCdLZn), the diagnostic performance of these 51 metabolites were assessed using receiver operating characteristic curve analysis and revealed that octadecylamine was a promising diagnostic indicator for evaluating the combined effects of Zn and Cd. Metabolomics analysis showed that the arginine and proline pathways were upregulated in HCdHZn compared with that in LCdLZn, suggesting a potential risk of obesity. Although higer levels of bovinic acid in HCdHZn vs. HCdLZn (high level of Cd and low level of Zn) indicated that Zn has antioxidant and anti-inflammatory properties, excessive Zn may still cause harmful effect to the human health and should be supplemented with caution. The study findings may be valuable for potential risk ahissessment of the combined effects of Cd-Zn and their interactions in pregnant women.

Spaceflight-Induced Gene Expression Profiles in the Mouse Brain Are Attenuated by Treatment with the Antioxidant BuOE

The demands of deep space pose a health risk to the central nervous system that has long been a concern when sending humans to space. While little is known about how spaceflight affects transcription spatially in the brain, a greater understanding of this process has the potential to aid strategies that mitigate the effects of spaceflight on the brain. Therefore, we performed GeoMx Digital Spatial Profiling of mouse brains subjected to either spaceflight or grounded controls. Four brain regions were selected: Cortex, Frontal Cortex, Corunu Ammonis I, and Dentate Gyrus. Antioxidants have emerged as a potential means of attenuating the effects of spaceflight, so we treated a subset of the mice with a superoxide dismutase mimic, MnTnBuOE-2-PyP 5+ (BuOE). Our analysis revealed hundreds of differentially expressed genes due to spaceflight in each of the four brain regions. Both common and region-specific transcriptomic responses were observed. Metabolic pathways and pathways sensitive to oxidative stress were enriched in the four brain regions due to spaceflight. These findings enhance our understanding of brain regional variation in susceptibility to spaceflight conditions. BuOE reduced the transcriptomic effects of spaceflight at a large number of genes, suggesting that this compound may attenuate oxidative stress-induced brain damage caused by the spaceflight environment.

Metals and metal isotopes incorporation in insect wings: Implications for geolocation and pollution exposure

Anthropogenic activities are exposing insects to elevated levels of toxic metals and are altering the bioavailability of essential metals. Metals and metal isotopes have also become promising tools for the geolocation of migratory insects. Understanding the pathways of metal incorporation in insect tissues is thus important for assessing the role of metals in insect physiology and ecology and for the development of metals and metal isotopes as geolocation tools. We conducted a diet-switching experiment on monarch butterflies [Danaus plexippus (L.)] with controlled larval and adult diets to evaluate the sources of 23 metals and metalloids, strontium isotopes, and lead isotopes to insect wing tissues over a period of 8 weeks. Concentrations of Ca, Co, Mo, and Sb differed between the sexes or with body mass. Ni and Zn bioaccumulated in the insect wing tissues over time, likely from the adult diet, while increases in Al, Cr, Cd, Cu, Fe, and Pb were, at least partially, from external sources (i.e., dust aerosols). Bioaccumulation of Pb in the monarch wings was confirmed by Pb isotopes to mainly be sourced from external anthropogenic sources, revealing the potential of Pb isotopes to become an indicator and tracer of metal pollution exposure along migratory paths. Concentrations of Ba, Cs, Mg, Na, Rb, Sr, Ti, Tl, and U appeared to be unaffected by intrinsic factors or additions of metals from adult dietary or external sources, and their potential for geolocation should be further explored. Strontium isotope ratios remained indicative of the larval diet, at least in males, supporting its potential as a geolocation tool. However, the difference in strontium isotope ratios between sexes, as well as the possibility of external contamination by wetting, requires further investigation. Our results demonstrate the complexity of metal incorporation processes in insects and the value of studying metals to develop new tools to quantify pollution exposure, metal toxicity, micronutrient uptake, and insect mobility.