Changes and sex- and age-related differences in the expression of drug metabolizing enzymes in a KRAS-mutant mouse model of lung cancer

Advanced N-glycoproteomics and proteomics approach revealed sexually dimorphic molecular signatures in primary mouse hepatocyte

Sexual dimorphism plays a critical role in disease pathophysiology, but the subtlety and complexity of these differences, along with a lack of precise comparative methods, hinder the advancement of precision medicine and drug development. This limitation is particularly evident in metabolic dysfunction-associated steatotic liver disease (MASLD), where sex-specific molecular mechanisms remain insufficiently understood. To address this gap, we employed an advanced integrative N-glycoproteomics and proteomics approach to systematically analyze sex-biased molecular signatures in primary mouse hepatocytes (PMHs) under healthy and MASLD conditions. Our analysis identified 280 sex-biased proteins and 39 sex-biased N-glycosites, and KEGG enrichment revealed that female-biased molecules were primarily involved in lipid metabolism, while male-biased molecules were associated with inflammation and cytoskeletal remodeling. A combined dataset of 302 sex-biased molecules was further analyzed using protein-protein interaction (PPI) analysis and Rc value calculations, resulting in the identification of 21 hub proteins and 2 hub N-glycosites as MASLD-associated sex-biased signatures. Notably, MASLD amplified proteomic sex differences while attenuating them in N-glycosylation. Western blot validation of key signatures, including female-biased MVK and male-biased LGALS3, highlighted distinct molecular adaptations between the sexes in MASLD progression. Our study introduced an advanced analytical framework for high-resolution comparative molecular profiling by integrating N-glycoproteomics with proteomics, providing valuable insights into sex-biased molecular signatures, enhancing preclinical model development, and advancing sex-specific therapeutic strategies in MASLD research and broader biological systems.

The Prebiotic Effect of Kaempferol in Regulating Bile Acid Metabolism

Kaempferol (Kae), as a homologous flavonoid, plays a pivotal role in human nutrition and disease treatment. This study endeavors to elucidate the in vivo metabolism of Kae and its potential to modulate the interplay between bile acids (BAs) and gut microbiota (GM). After Kae administration, we analyzed pharmacokinetics, BA levels, and drug metabolic enzymes (DMEs) amount using LC-MS/MS. Subsequently, we checked the gene and protein expression with qRT-PCR and western blot and studied the changes in GM using 16S rRNA sequencing, accompanying in-depth data analysis. Finally, molecular docking was employed to explore Kae's interaction with the Farnesoid X receptor (FXR). Kae enhances its own absorption and metabolic circulation in vivo by upregulating the UDP-Glucuronosyltransferases (UGTs) expression. Furthermore, Kae significantly suppressed the expression of cholesterol 7α-hydroxylase (CYP7A1) while concurrently elevating the sterol 27-hydroxylase (CYP27A1) expression, by activating the liver FXR, a nuclear transcription factor involved in the regulation of CYPs and UGTs enzymes. For BA analysis, Kae induced the upregulation of tauro-BAs by attenuating the activity of bile salt hydrolases (BSH), which correlated with shifts in the GM composition. Specifically, Kae increased the abundance of beneficial bacteria such as Bacteroides acidifaciens and Bifidobacterium choerinum, while reduced populations of species associated with BSH deconjugation. The study indicates that Kae may serve as a prebiotic, modulating the BA-GM interaction to confer nutritional and therapeutic advantages.

PPARα activator irbesartan suppresses the proliferation of endometrial carcinoma cells via SREBP1 and ARID1A

Endometrial carcinoma (EMC) is associated with obesity; however, the underlying mechanisms have not yet been elucidated. Peroxisome proliferator-activated receptor alpha (PPARα) is a nuclear receptor that is involved in lipid, glucose, and energy metabolism. PPARα reportedly functions as a tumor suppressor through its effects on lipid metabolism; however, the involvement of PPARα in the development of EMC remains unclear. The present study demonstrated that the immunohistochemical expression of nuclear PPARα was lower in EMC than in normal endometrial tissues, suggesting the tumor suppressive nature of PPARα. A treatment with the PPARα activator, irbesartan, inhibited the EMC cell lines, Ishikawa and HEC1A, by down-regulating sterol regulatory element-binding protein 1 (SREBP1) and fatty acid synthase (FAS) and up-regulating the tumor suppressor genes p21 and p27, antioxidant enzymes, and AT-rich interaction domain 1A (ARID1A). These results indicate the potential of the activation of PPARα as a novel therapeutic approach against EMC.

Peroxisome Proliferator-Activated Receptors (PPARs) and Oxidative Stress in Physiological Conditions and in Cancer

Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear hormone receptor superfamily. Originally described as “orphan nuclear receptors”, they can bind both natural and synthetic ligands acting as agonists or antagonists. In humans three subtypes, PPARα, β/δ, γ, are encoded by different genes, show tissue-specific expression patterns, and contribute to the regulation of lipid and carbohydrate metabolisms, of different cell functions, including proliferation, death, differentiation, and of processes, as inflammation, angiogenesis, immune response. The PPAR ability in increasing the expression of various antioxidant genes and decreasing the synthesis of pro-inflammatory mediators, makes them be considered among the most important regulators of the cellular response to oxidative stress conditions. Based on the multiplicity of physiological effects, PPAR involvement in cancer development and progression has attracted great scientific interest with the aim to describe changes occurring in their expression in cancer cells, and to investigate the correlation with some characteristics of cancer phenotype, including increased proliferation, decreased susceptibility to apoptosis, malignancy degree and onset of resistance to anticancer drugs. This review focuses on mechanisms underlying the antioxidant and anti-inflammatory properties of PPARs in physiological conditions, and on the reported beneficial effects of PPAR activation in cancer.