Methyl jasmonate induces cell death and loss of hydrogenosomal membrane potential in Trichomonas vaginalis

Trichomonas vaginalis is an important human parasite of the urogenital tract. Jasmonates are a group of small lipids that are produced in plants and function as stress hormones. Naturally occurring methyl jasmonate (MJ) has been used to treat several types of cancer cells and it is cytotoxic to protistan parasites. It has been suggested that mitochondria are the target organelles of jasmonates. Here, we tested this drug against T. vaginalis. Although metronidazole has been the drug of choice for trichomoniasis, side effects from this treatment are common, and nausea and dizziness have been reported in up to 12% of patients. In addition, there has been increased recognition of resistance to metronidazole. We demonstrate here using flow cytometry, JC-1 and scanning and transmission electron microscopy that MJ induced the cell death of T. vaginalis parasites. Our results are discussed with previous findings published by others.

Effects of intestinal ischemia/reperfusion injury on gastric acid secretion

BACKGROUND

The mechanism responsible for gastric colonization in critically injured ICU patients remains to be fully elucidated. Moreover, the effects of gut ischemia/reperfusion (I/R) injury on gastric function are unclear. It was our hypothesis that gut I/R injury would cause gastric dysfunction.

MATERIALS AND METHODS

Rats were anesthetized and, via laparotomy, the superior mesenteric artery (SMA) was clamped at its aortic origin for 45 min followed by clamp removal. Rats were allowed to awaken and then killed after 6 h of reperfusion. Control rats underwent laparotomy with SMA isolation. Stomachs were removed, gastric fluid was aspirated, and the volume, pH, and protein, bicarbonate, and glucose contents were determined. Serum and antral mucosa were prepared for gastrin radioimmunoassay and the glandular mucosa was assessed for morphologic injury.

RESULTS

SMA I/R injury caused significant accumulation of gastric luminal fluid that was alkaline and rich in protein, glucose, and bicarbonate content when compared with sham controls. SMA I/R injury also caused gastric surface epithelial cell injury and significantly increased serum and antral gastrin levels. In additional rats, gut I/R injury inhibited basal acid secretion and blunted the acid secretory response to pentagastrin.

CONCLUSIONS

This study demonstrated for the first time that small intestinal I/R injury causes significant gastric dysfunction. The findings suggest that this type of injury, a frequent occurrence in critically injured ICU patients, may predispose patients to gastric colonization due to stasis and loss of the natural bactericidal effects of gastric acid.