Shen, W.-C. | Search bioRxiv

bioRxiv2023

MiR-221/222-enriched ADSC-exosome mitigates PM exposure-exacerbated cardiac ischemia/reperfusion injury through the modulation of the BNIP3/LC3B/PUMA pathway

BackgroundEpidemiology has demonstrated a strong relationship between fine particulate matter (PM) exposure and cardiovascular disease. Whether PM aggravates myocardial ischemia/reperfusion (I/R) injury and its related mechanisms remain unclear. Our previous study showed that adipose stem cell-derived exosomes (ADSC-Exo) contain a large amount of miR-221/222. This study investigated the effects of PM exposure on I/R-induced cardiac injury through mitophagy and apoptosis, as well as the potential role of miR-221/222 in ADSC-Exo. MethodsWild-type, miR-221/222 knockout (miR-221/222 KO), and miR-221/222 overexpressed transgenic (miR-221/222 TG) mice were intratracheally injected with 100 g/kg PM for 24 h before I/R treatment. Ischemia was induced by temporarily occluding the left anterior descending (LAD) coronary artery with sutures for 30 min, followed by 3 h of reperfusion. In an in vitro model, H9c2 cells were exposed to 50 g/mL PM for 6 h and subjected to hypoxia (1% O2) at 37{degrees}C for 6 h, followed by 12 h reoxygenation. ResultsPM aggravates I/R (H/R)-induced cardiac injury by increasing ROS levels and causing mitochondrial dysfunction, leading to an increase in mitochondrial fission-related proteins like Drp1 and Mff, mitophagy-related proteins such as BNIP3 and LC3B, as well as apoptosis-related proteins like PUMA and p-p53 in vivo and in vitro studies. In comparison, transfection of ADSC-Exo and miR-221/222 mimics significantly reduced PM+I/R (H/R)-induced cardiac injury. Importantly, ADSC-Exo contains miR-221/222, which directly targets BNIP3, LC3B, and PUMA, decreasing their expression and ultimately reducing cardiomyocyte mitophagy and apoptosis. ConclusionsThe study showed that PM aggravates I/R or H/R-induced cardiac injury, and ADSC-Exo treatment significantly reduced this by regulating mitophagy and apoptosis through miR-221/222/BNIP3/LC3B/PUMA.

cell biology↗

bioRxiv2018

Mating system of Ustilago esculenta and its polymorphism

Zizania latifolia Turcz., which is mainly distributed in Asia, has had a long cultivation history as a cereal and vegetable crop. On infection with the smut fungus Ustilago esculenta, Z. latifolia becomes an edible vegetable, water bamboo. Two main cultivars, with a green shell and red shell, are cultivated for commercial production in Taiwan. Previous studies indicated that cultivars of Z. latifolia may be related to infection with U. esculenta isolates. However, related research is limited. The infection process of the corn smut fungus Ustilago maydis is coupled with sexual development and under control of the mating type locus. Thus, we aimed to use knowledge of U. maydis to reveal the mating system of U. esculenta. We collected water bamboo and isolated 145 U. esculenta strains from Taiwans major production areas. By using PCR and idiomorph screening among meiotic offspring and field isolates, we identified three idiomorphs of the mating type locus and found no sequence recombination between them. Whole-genome sequencing (Illumina and Pacbio) suggested that the mating system of U. esculenta was bipolar. Mating type locus 1 (MAT-1) was 555,862 bp, and contained 44% repeated sequences. Sequence comparison revealed that U. esculenta MAT-1 shared better conservation with the sex chromosome of U. maydis than U. hordei. These results can be utilized to further explore the genomic diversity of U. esculenta isolates and their application for water bamboo breeding.

microbiology↗