The dynamic activity of transposable elements (TEs) contributes to the vast diversity of genome size and architecture among plants. Here, we examined the genomic distribution and transposition activity of long terminal repeat retrotransposons (LTR-RTs) in Arabidopsis thaliana (Ath) and three of its relatives, Arabidopsis lyrata (Aly), Eutrema salsugineum (Esa), and Schrenkiella parvula (Spa), in Brassicaceae. Our analyses revealed the distinct evolutionary dynamics of Gypsyretrotransposons, which reflects the different patterns of genome size changes of the four species over the past million years. The rate of Gypsy transposition in Aly is approximately five times more rapid than that of Ath and Esa, suggesting an expanding Aly genome. Gypsy insertions in Esa are strictly confined to pericentromeric heterochromatin and associated with dramatic centromere expansion. In contrast, Gypsy insertions in Spa have been largely suppressed over the last million years, likely as a result of a combination of an inherent molecular mechanism of preferential DNA removal and purifying selection at Gypsy elements. Additionally, species-specific clades of Gypsy elements shaped the distinct genome architectures of Aly and Esa.

We have recently shown that both UVB and BaP can induce the production of ROS, apoptosis and even cancer. However, the differences in the metabolic profiles of skin damaged by UVB, BaP or UVB combined with BaP have not been studied. Therefore, we examined the metabolic changes in the human foreskin fibroblast injured by UVB or BaP or the combination of the two, using ultra performance liquid chromatography (UPLC) coupled with quadrupole time-of-flight mass spectrometry (qTOF-MS). 24 metabolites were altered in the UVB damage group, 25 in the BaP damage group, and 33 in the UVB combined with BaP group. These alterations indicated that the metabolic mechanisms of HFF-1 cells treated with UVB or BaP are related to multiple main metabolites including glycerophosphocholine (PC), lactosylceramide (LacCer), guanidinosuccinic acid (GSA), glutathione(GSH), and lysophosphatidylcholine (LysoPC) and the main mechanisms involved glycerophospholipid and glutathione metabolism. Thus, our report provided useful insight into the underlying mechanisms of UVB and BaP damage to skin cells.

Marine mangrove vegetation has been traditionally employed in folk medicine to address various ailments. Notably, Rhizophora apiculata Blume has exhibited noteworthy properties, demonstrating efficacy against cancer, viruses, and bacteria. The enzyme fatty acid synthase (FAS) plays a pivotal role in de novo fatty acid synthesis, making it a promising target for combating colon cancer. Our study focused on evaluating the FAS inhibitory effects of both the crude extract and three isolated compounds from R. apiculata. The n-butanol fraction of R. apiculata extract (BFR) demonstrated a significant inhibition of FAS, with an IC₅₀ value of 93.0 µg/mL. For inhibition via lyoniresinol-3α-O-β-rhamnopyranoside (LR), the corresponding IC₅₀ value was 20.1 µg/mL (35.5 µM). LR competitively inhibited the FAS reaction with acetyl-CoA, noncompetitively with malonyl-CoA, and in a mixed manner with NADPH. Our results also suggest that both BFR and LR reversibly bind to the KR domain of FAS, hindering the reduction of saturated acyl groups in fatty acid synthesis. Furthermore, BFR and LR displayed time-dependent inhibition for FAS, with k_obs values of 0.0045 min⁻¹ and 0.026 min⁻¹, respectively. LR also exhibited time-dependent inhibition on the KR domain, with a k_obs value of 0.019 min⁻¹. In human colon cancer cells, LR demonstrated the ability to reduce viability and inhibit intracellular FAS activity. Notably, the effects of LR on human colon cancer cells could be reversed with the end product of FAS-catalyzed chemical reactions, affirming the specificity of LR on FAS. These findings underscore the potential of BFR and LR as potent FAS inhibitors, presenting novel avenues for the treatment of human colon cancer.

Background/Objective: With rising per capita sugar consumption, skin glycation-related issues including dullness, homeostasis disruption and accelerated wrinkling have gained widespread attention. However, globally standardized and rigorous evaluation criteria for anti-glycation efficacy remain lacking. This study aimed to establish stage-specific glycation injury cell models and elucidate the stage-dependent molecular mechanisms of glycation-induced fibroblast damage, providing a standardized reference for anti-glycation efficacy assessment. Methods: Three glycation injury models were constructed in human foreskin fibroblasts (HFF-1): early-stage (glucose-induced), intermediate-stage (glyoxal-induced), and late-stage (advanced glycation end products (AGEs)-induced). Core biomarkers including Nε-(carboxymethyl)lysine (CML), collagen type I (Col I) and elastin (ELN) were used to optimize modeling conditions via Cell Counting Kit-8 (CCK-8) and enzyme-linked immunosorbent assay (ELISA). Untargeted metabolomics based on ultra-high-performance liquid chromatography (UHPLC)-Q Exactive Orbitrap was applied to identify differential metabolites and perturbed pathways, following Metabolomics Standards Initiative (MSI) Level 2 identification criteria. Results: Optimal conditions were determined as 50 mmol/L glucose for 48 h, 0.5 mmol/L glyoxal for 48 h, and 200 μg/mL AGEs for 24 h. A total of 319, 34 and 148 differential metabolites were identified in the three groups, respectively. Six key pathways were significantly perturbed. Early and intermediate models shared similar mechanisms (purine metabolism disturbance), while the late model showed distinct alterations in pyrimidine, nicotinate, arachidonic acid and steroid hormone metabolism. Conclusions: Three stable stage-specific glycation models were successfully established in HFF-1 cells. Significant differences in metabolic profiles and mechanisms exist across the three stages, providing a rational basis for model selection and theoretical support for anti-glycation efficacy evaluation.