Associations between serum ferritin baselines and trajectories and the incidence of metabolic dysfunction-associated steatotic liver disease: a prospective cohort study.

BACKGROUND AND AIMS: Evidence from prospective cohort studies on the relationship between metabolic dysfunction-associated steatotic liver disease (MASLD) and longitudinal changes in serum ferritin (SF) still limited. This study aimed to investigate the associations of SF baselines and trajectories with new-onset MASLD and to present a MASLD discriminant model. METHODS: A total of 1895 participants who attended health examinations at least three times in a hospital in Dalian City between 2015 and 2022 were included. The main outcome was the incidence of MASLD. The associations between SF baselines and trajectories with the risk of MASLD were analyzed by Cox proportional hazards regression, restricted cubic spline (RCS) analysis and time-dependent receiver operating characteristic (ROC) curve analysis. In addition, a MASLD discrimination model was established using logistic regression analyses. RESULTS: Among the 1895 participants, 492 developed MASLD during follow-up. Kaplan-Meier analysis indicated that participants in the low-stable trajectory group had a longer MASLD-free time compared with participants in other groups. Compared with those in the low-stable trajectory group, the adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) for the risk of new-onset MASLD in the medium-high, high-stable and high-high trajectory groups were 1.54(1.18-2.00), 1.77(1.35-2.32) and 1.55(1.07-2.26), respectively (Ptrend < 0.001). The results were robust in subgroup and sensitivity analyses. Multivariate Cox proportional regression showed that SF was an independent risk factor of MASLD (HR = 1.002, 95%CI: 1.000-1.003, P = 0.003). The restricted cubic spline demonstrated a nonlinear relationship between SF and the risk of MASLD. The 8-variable model had high discriminative performance, good accuracy and clinical effectiveness. The ROC curve results showed that AUC was greater than that of the FLI, HSI and ZJU models (all P < 0.01). CONCLUSIONS: Not only a higher baseline SF but also SF changing trajectory are significantly associated with risk of new-onset MASLD. SF could be a predictor of the occurrence of MASLD.

Antisense suppression of an acid invertase gene (MAI1) in muskmelon alters plant growth and fruit development.

To unravel the roles of soluble acid invertase in muskmelon (Cucumis melo L.), its activity in transgenic muskmelon plants was reduced by an antisense approach. For this purpose, a 1038 bp cDNA fragment of muskmelon soluble acid invertase was expressed in antisense orientation behind the 35S promoter of the cauliflower mosaic virus. The phenotype of the antisense plants clearly differed from that of control plants. The transgenic plant leaves were markedly smaller, and the stems were obviously thinner. Transmission electron microscopy revealed that degradation of the chloroplast membrane occurred in transgenic leaves and the number of grana in the chloroplast was significantly reduced, suggesting that the slow growth and weaker phenotype of the transgenic plants may be due to damage to the chloroplast ultrastructure, which in turn resulted in a decrease in net photosynthetic rate. The sucrose concentration increased and levels of acid invertase decreased in transgenic fruit, and the fruit size was 60% smaller than that of the control. In addition, transgenic fruit reached full-slip at 25 d after pollination (DAP), approximately 5 d before the control fruit (full-slip at 30 DAP), and this accelerated maturity correlated with a dramatic elevation of ethylene production at the later stages of fruit development. Together, these results suggest that soluble acid invertase not only plays an important role during muskmelon plant and fruit development but also controls the sucrose content in muskmelon fruit.