Cytotoxicity and Proteasome Inhibition by Alkaloid Extract from Murraya koenigii Leaves in Breast Cancer Cells-Molecular Docking Studies.

Murraya koenigii (curry tree) leaves are rich in bioactive compounds such as flavonoids, alkaloids, and coumarins. Alkaloids from M. koenigii leaves have antianalgesic, antiulcerogenic, antiobesity, and antitumor activities. In this study, we tested the cytotoxic and proteasome-inhibitory potential of a total alkaloid extract (TAE) from M. koenigii leaves in the breast cancer cell line MDA-MB-231. The TAE decreased cell viability with an IC50 of 14.4 µg/mL and altered growth kinetics of breast cancer cells. TAE (32 µg/mL) arrested cells (35%) in the "S" phase of the cell cycle and induced apoptosis. The 26S proteasome, a multicatalytic protease complex, promotes tumor cell proliferation and protects tumor cells from apoptosis. The TAE and mahanine, a carbazole alkaloid present in M. koenigii leaves, preferentially inhibited the trypsin-like, but not the chymotrypsin-like proteolytic activity of the proteasome with an IC50 of 162 µg/mL and 287 µM, respectively. In silico analysis of 26 compounds from M. koenigii leaves revealed significant docking scores for mahanine and two other carbazole alkaloids with the ß2 and ß5 subunits of the catalytic 20S proteasome. Taken together, this study demonstrates that inhibition of the proteasome is an important biological activity of M. koenigii alkaloids, which may lead to cancer cell death.

Associations between procalcitonin and markers of bacterial sepsis.

BACKGROUND: Bacterial sepsis with no bacterial isolates can be a difficult clinical conundrum, where other markers like C-reactive protein (CRP), white cell count (WCC), and neutrophilia are helpful to arrive at a diagnosis. Procalcitonin (PCT) has been shown to be a useful biomarker in bacterial sepsis. The aim of the study was to look at the association of PCT with bacterial cultures and compare this to currently used markers of bacterial sepsis. MATERIAL AND METHODS: WCC, neutrophil count, and CRP with PCT were compared in patients with a positive bacterial culture from blood/body fluid. The specificity and sensitivity of PCT were compared with those of CRP. RESULTS: Of the 99 paired samples obtained, 25 cultures were positive for bacteria. There was a significant difference in CRP (P=0.04) and PCT (P<0.001) levels between culture-positive and culture-negative samples. PCT had a better sensitivity and specificity than CRP (84% and 64.9% vs. 69.6% and 52.9%, respectively), with a combined specificity (CRP and PCT) of 83.5%. CONCLUSIONS: PCT has a better association with bacterial sepsis and is superior to currently available biomarkers in the clinical setting. The rapid pharmacodynamics of PCT can serve as an early predictor of the diagnosis of bacterial sepsis while awaiting the bacterial culture results avoiding undue delay in the institution of antibiotics, hence, potentially improving the prognosis of patients with bacterial sepsis.

Tumor necrosis factor alpha (TNF-α) autoregulates its expression and induces adhesion molecule expression in asthma.

Subjects with mild asthma underwent repeated low-dose allergen exposure and bronchial biopsies were examined for the expression of TNF-α and adhesion molecules. Bronchial biopsies from moderately severe asthmatics were then tested in an explant culture system to assess the effect of Der p and CDP-870, a TNF-α blocking pegylated-antibody Fab, on expression of TNF-α and adhesion molecules. Low-dose allergen challenge significantly upregulated sub-mucosal mast cells, TNF-α(+) cells, and VCAM. When bronchial explants were exposed to Der p and CDP 870 for 24h, CDP 870 caused a significant reduction in TNF-α release both at baseline and following stimulation with Der p allergen. The bronchial biopsies showed significant upregulation of TNF-α positive cells and ICAM-1 following exposure to Der p (p=0.03) and this was reduced in the presence of CDP-870. So, allergen exposure up-regulates TNF-α expression in asthma and down-stream targets, including adhesion molecules that contribute to airway inflammation.