Maternal protein deficiency impairs peroxisome biogenesis and leads to oxidative stress and ferroptosis in liver of fetal growth restriction offspring

Maternal protein restriction compromises hepatic phenotype and antioxidant defense in postweaning male rats, while females exhibit resilience

The Developmental Origins of Health and Disease (DOHaD) concept postulates that maternal malnutrition can program offspring for dysfunction of multiple systems, including the liver. Maternal Protein Restriction (MPR) is a maternal malnutrition model that dysregulates catabolic hormones early in life, with long-term consequences on offspring such as hypertension and reproductive system cancers. Furthermore, studies evaluating sex-specific differences are scarce, especially considering the consequences of MPR on early life. Here, we investigated the impacts of MPR on hepatic phenotypic and molecular aspects of male and female rats at postnatal day (PND)21. The rats were divided into two groups: CTR, from dams that consumed a normal-protein diet (17 % protein), or GLLP, from dams that consumed a low-protein diet (6 % protein) throughout gestation and lactation. Our results demonstrated that MPR leads to an increase in collagen fibers, glycogen, and peroxiredoxin 1, in addition to a decrease in reticular fibers, mast cells, GSH, and MDA in the liver of male rats. In females, a reduction of reticular fibers and protein expression of hepatic peroxiredoxin 4 was observed. By contrasting these results with in silico analyses, we suggest that the main altered mechanisms in males are associated with oxidative stress, glycogen metabolism, and inflammatory responses. In females, a subtle dysregulation of antioxidant activity within the extracellular matrix was noted. Therefore, this work demonstrates sex-specific hepatic differences in post-weaning rats exposed to MPR, highlighting possible maternal modulations that lead males to be more affected, which may generate long-term effects on hepatic and systemic health.

N-glycosylation Modification Reveals Insights into the Oxidative Reactions of Liver in Wuzhishan Pigs

Although porcine liver contributes to their growth and development by nutrition production and energy supply, oxidative stress-induced hepatocyte damage is inevitable during metabolism. N-glycosylation is a common modification in oxidation; nevertheless, the effects of N-glycosylation on pig liver oxidative reactions remain undefined. In this study, liver proteins with N-glycosylation were detected in Wuzhishan (WZS) pigs between 4 and 8 months old and Large White (LW) pigs at 4 months old based on LC-MS/MS. The results showed that the number of differentially expressed proteins (DEPs) was larger between different pig cultivars than that between WZS pigs at various growth periods. The enriched pathways of DEPs were mainly related to oxidative reactions, and 10 proteins were finally selected that primarily consisted of CYPs, GSTs and HSPs with expressions significantly correlating to liver size and weight. The oxidative genes shared N-glycosylation-modified models of N-x-S and N-G. Five out of 10 proteins were upregulated in WZS pigs compared to LW pigs at 4 months old, while five proteins increased in WZS pigs from 4 to 8 months old. In conclusion, this research provides valuable information on the N-glycosylation motifs in liver oxidation genes of WZS pigs.

Elucidating the susceptibility to breast cancer: an in-depth proteomic and transcriptomic investigation into novel potential plasma protein biomarkers

Objectives: This study aimed to identify plasma proteins that are associated with and causative of breast cancer through Proteome and Transcriptome-wide association studies combining Mendelian Randomization. Methods: Utilizing high-throughput datasets, we designed a two-phase analytical framework aimed at identifying novel plasma proteins that are both associated with and causative of breast cancer. Initially, we conducted Proteome/Transcriptome-wide association studies (P/TWAS) to identify plasma proteins with significant associations. Subsequently, Mendelian Randomization was employed to ascertain the causation. The validity and robustness of our findings were further reinforced through external validation and various sensitivity analyses, including Bayesian colocalization, Steiger filtering, heterogeneity and pleiotropy. Additionally, we performed functional enrichment analysis of the identified proteins to better understand their roles in breast cancer and to assess their potential as druggable targets. Results: We identified 5 plasma proteins demonstrating strong associations and causative links with breast cancer. Specifically, PEX14 (OR = 1.201, p = 0.016) and CTSF (OR = 1.114, p < 0.001) both displayed positive and causal association with breast cancer. In contrast, SNUPN (OR = 0.905, p < 0.001), CSK (OR = 0.962, p = 0.038), and PARK7 (OR = 0.954, p < 0.001) were negatively associated with the disease. For the ER-positive subtype, 3 plasma proteins were identified, with CSK and CTSF exhibiting consistent trends, while GDI2 (OR = 0.920, p < 0.001) was distinct to this subtype. In ER-negative subtype, PEX14 (OR = 1.645, p < 0.001) stood out as the sole protein, even showing a stronger causal effect compared to breast cancer. These associations were robustly supported by colocalization and sensitivity analyses. Conclusion: Integrating multiple data dimensions, our study successfully pinpointed plasma proteins significantly associated with and causative of breast cancer, offering valuable insights for future research and potential new biomarkers and therapeutic targets.