Chu, T.-Y. | Search bioRxiv

bioRxiv2024

Bioenergetic stress potentiates antimicrobial resistance and persistence

Antimicrobial resistance (AMR) is a global health crisis and there is an urgent need to better understand AMR mechanisms. Antibiotic treatment alters several aspects of bacterial physiology, including increased ATP utilization, carbon metabolism, and reactive oxygen species (ROS) formation. However, how the "bioenergetic stress" induced by increased ATP utilization affects treatment outcomes is unknown. Here we utilized a synthetic biology approach to study the direct effects of bioenergetic stress on antibiotic efficacy. We engineered a genetic system that constitutively hydrolyzes ATP or NADH in Escherichia coli. We found that bioenergetic stress potentiates AMR evolution via enhanced ROS production, mutagenic break repair, and transcription-coupled repair. We also find that bioenergetic stress potentiates antimicrobial persistence via potentiated stringent response activation. We propose a unifying model that antibiotic-induced antimicrobial resistance and persistence is caused by antibiotic-induced. This has important implications for preventing or curbing the spread of AMR infections.

microbiology↗

bioRxiv2021

Ovulation sources coagulation protease cascade and hepatocyte growth factor to support physiological growth and malignant transformation

The fallopian tube fimbrial epithelium (FTE), which is exposed to the follicular fluid (FF) contents of ovulation, is regarded as the main origin of ovarian high-grade serous carcinoma (HGSC). Previously, we found that growth factors in FF, such as IGF2, are responsible for the malignant transformation of FTE. However, ovulation is a monthly transient event, whereas carcinogenesis requires continuous, long-term exposure. Here, we found the transformation activity of FF sustained for more than 30 days after drainage into the peritoneal fluid (PF). Hepatocyte growth factor (HGF), activated through the ovulation injury-tissue factor-thrombin-HGFA-HGF cleavage cascade confers a sustained transformation activity to FTE, HGSC. Physiologically, the high reserve of the coagulation-HGF cascade sources a sustained level of HGF in PF, then to the blood circulation. This HGF axis promotes the growth of the corpus luteum and repair of tissue injury after ovulation. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=172 SRC="FIGDIR/small/448625v1_ufig1.gif" ALT="Figure 1"> View larger version (45K): org.highwire.dtl.DTLVardef@13d26d3org.highwire.dtl.DTLVardef@1c00c35org.highwire.dtl.DTLVardef@1619373org.highwire.dtl.DTLVardef@117a24d_HPS_FORMAT_FIGEXP M_FIG C_FIG The fluid content of the ovulating ovarian follicle (follicular fluid [FF]) exerts a long-lasting transformation effect that is sustained after mixing with peritoneal fluid (PF). The coagulation protease cascade and hepatocyte growth factor (HGF) are responsible for the sustained activity. The high abundance of cascade proteins and pro-form HGF activator and HGF in FF/PF supports the constant supply of active-form HGF lasting for a whole month, covering the entire ovulation cycle. This sustained HGF activity promotes the proliferative repair of the ovarian surface and fallopian tube fimbrial epithelia as well as the growth of the corpus luteum. The same activity also inadvertently promotes the malignant transformation of the fimbrial epithelium, high-grade serous carcinoma, and epithelial ovarian cancer. In addition to the peritoneal cavity, ovulation sources HGF to blood circulation, which may serve an endocrine role. HIGHLIGHTO_LIOvulatory follicular fluid (FF) exerts a long-lasting transformation activity covering throughout the ovulation cycle. C_LIO_LIThe ovulation injury-coagulation proteases-hepatocyte growth factor (HGF) cascade is responsible for the sustained activity. C_LIO_LIOvulation sources HGF into the peritoneal cavity, then into the blood circulation. C_LIO_LIThis coagulation-HGF cascade promotes the transformation of fallopian tube epithelial cells and ovarian cancer cells. C_LIO_LIPhysiologically, it promotes the growth of the corpus luteum and injured epithelium after ovulation. C_LI

cancer biology↗