Hydrogen peroxide positively regulates ABA signaling via oxidative modification of the C2H2-type zinc finger protein ZFP36 in rice.

The rice zinc finger protein ZFP36 serves as a pivotal regulator of the hydrogen peroxide (H2O2) signaling pathway in response to abscisic acid (ABA). Its role is crucial for integrating H2O2 signals with the plant defense mechanisms against water deficit and oxidative stress. However, it remains unclear whether ZFP36 directly modulates ABA-induced H2O2 signaling. This study explored the effects of oxidative post-translational modifications (OxiPTMs) on ZFP36 in rice, with an emphasis on the H2O2-induced oxidation through its cysteine (Cys) residues. We found that ZFP36 undergoes oxidative modification as a target of H2O2 in the presence of ABA, specifically at Cys32. Employing quantitative detection and fluorescence assays, we observed that ZFP36 oxidation enhances the expression and activity of genes encoding protective antioxidant enzymes. Moreover, our investigation into the thioredoxin (Trx) and glutaredoxin (Grx) families revealed that OsTrxh1 facilitates the reduction of oxidized ZFP36. Genetic evidence indicates that ZFP36 positively influences rice resilience to oxidative and water stress, while OsTrxh1 exerts an opposing effect. These insights reveal a distinctive pathway for plant cells to perceive ABA-induced H2O2 signaling, advance our comprehension of H2O2 signaling dynamics, and ABA-related plant responses, and lay a vital groundwork for enhancing crop stress tolerance.

Relationship between social isolation and glycaemic control of people previously diagnosed with diabetes: secondary analysis from the CHARLS.

OBJECTIVES: Social isolation may affect diabetes self-management. This study aimed to explore the relations between social isolation and glycaemic control in patients with diabetes and to explore lifestyle differences among individuals with different levels of social isolation. METHODS: The relevant data of 665 people previously diagnosed with diabetes included in the China Health and Retirement Longitudinal Study from 2011 to 2015 were extracted and analysed. The study included patient general information, blood glucose, lipids, glycosylated haemoglobin, social isolation index, health-related lifestyle factors and diabetes-related factors. Differences in metabolic abnormalities and modifiable lifestyles were compared among patients with varying levels of social isolation. RESULTS: Multiple linear regression analysis demonstrated that among men aged 45-64 years, the high social isolation group had significantly higher glycosylated haemoglobin levels compared with the low isolation group (7.29±1.81 vs 6.59±1.63, p=0.026). A positive correlation was observed between social isolation and blood glucose (ß=14.16; 95% CI 2.75 to 25.57; p=0.015) and glycosylated haemoglobin (ß=0.35; 95% CI 0.10 to 0.60; p=0.006), indicating that higher social isolation was associated with higher fasting blood glucose and glycosylated haemoglobin levels. However, no significant associations were observed in other age groups. Notably, men aged 45-65 years with high social isolation had higher depression rates (44.10% vs 24.60%, p=0.024), lower engagement in moderate exercise (5.70% vs 23.50%, p=0.019) and shorter 10-minute walks (17.10% vs 36.80%, p=0.027). Differences in other health-related and diabetes-related factors were not statistically significant. CONCLUSION: Middle-aged men with diabetes with higher social isolation tend to have higher blood glucose and glycosylated haemoglobin levels. This subset of patients requires targeted attention to provide social support from family and friends for improved glycaemic control. If necessary, education on diabetes should be made available to family members and friends.

Securinine inhibits the tumor growth of human bladder cancer cells by suppressing Wnt/ß-catenin signaling pathway and activating p38 and JNK signaling pathways.

Bladder cancer (BC) is the most common malignant tumor in urinary system. Although chemotherapy is one of the most important adjuvant treatments for BC, drug resistance, non-specific toxicity and severe side effects are the major obstacles to BC chemotherapy. Natural products have always been a leading resource of antitumor drug discovery, with the advantages of excellent effectiveness, low toxicity, multi-targeting potency and easy availability. In this study, we evaluated the potential anti-tumor effect of securinine (SEC), a natural alkaloid from Securinega suffruticosa, on BC cells in vitro and in vivo, and delineated the underlying mechanism. We found that SEC inhibited the proliferation, migration and invasion, induced the apoptosis of BC cells in vitro, and retarded the xenograft tumor growth of BC cell in vivo. Notably, SEC had a promising safety profile because it presented no or low toxicity on normal cells and mice. Mechanistically, SEC inactivated Wnt/ß-catenin signaling pathway while activated p38 and JNK signaling pathway. Moreover, ß-catenin overexpression, the p38 inhibitor SB203580 and the JNK inhibitor SP600125 both mitigated the inhibitory effect of SEC on BC cells. Furthermore, we demonstrated a synergistic inhibitory effect of SEC and gemcitabine (GEM) on BC cells in vitro and in vivo. Taken together, our findings suggest that SEC may exert anti-BC cell effect at least through the activation of p38 and JNK signaling pathways, and the inhibition of Wnt/ß-catenin signaling pathway. More meaningfully, the findings indicate that GEM-induced BC cell killing can be enhanced by combining with SEC.