Backstabbing P-gp: Side-Chain Cleaved Ecdysteroid 2,3-Dioxolanes Hyper-Sensitize MDR Cancer Cells to Doxorubicin without Efflux Inhibition

P-glycoprotein (P-gp, ABCB1) over-expression, causing a multi-drug resistant (MDR) phenotype, is a major problem in cancer chemotherapy that urgently requires novel approaches. Our previous studies showed certain ecdysteroid derivatives as promising chemo-sensitizers against MDR and non-MDR cancer cell lines while also exerting mild to moderate inhibition of P-gp function. Here we report the preparation of a set of substituted 2,3-dioxolane derivatives of poststerone, a known in vivo metabolite of 20-hydroxyecdysone (20E). In contrast with previously studied ecdysteroid dioxolanes, the majority of the new compounds did not inhibit the efflux function of P-gp. Nevertheless, a strong, dose dependent sensitization to doxorubicin was observed on a P-gp transfected cancer cell line and on its susceptible counterpart. We also observed that the MDR cell line was more sensitive to the compounds’ effect than the non-MDR. Our results showed for the first time that the chemo-sensitizing activity of ecdysteroids can be fully independent of functional efflux pump inhibition, and suggest these compounds as favorable leads against MDR cancer

Adaptation and validation of the Hungarian version of the Yale Food Addiction Scale for Children

Background: Childhood obesity proves to be an important public health issue, since it serves as a potential risk factor for multiple diseases. Food addiction could also serve as an important etiological factor. As childhood obesity plays a serious issue also in Hungary, we aimed to adapt and validate the Hungarian version of the Yale Food Addiction Scale for Children (H-YFAS-C). Methods: A total of 191 children were assessed with the H-YFAS-C and the Eating Disorder Inventory (EDI). The following psychometric properties were analyzed: internal consistency, construct validity, convergent, and discriminant validity. Results: A good construct validity was revealed by confirmatory factor analysis (RMSEA = 0.0528, CFI = 0.896, χ2 value = 279.06). Question 25 proved to have no significant effect on its group and was removed from further analyses. The Kuder–Richardson 20 coefficient indicated good internal consistency (K20 = 0.82). With the use of the eight EDI subscales, a good convergent and discriminant validity could be determined. Food addiction was diagnosed in 8.9% of children. The mean symptom count was 1.7 ± 1.2 (range: 0–7). Females were more often diagnosed with food addiction than males (p = .016; OR = 3.6, 95% CI: 1.2–10.6). BMI percentiles were significantly higher in children with diagnosed food addiction (p = .003). There proved to be no correlation between age and the occurrence of food addiction. Discussion and conclusion: Our results show that H-YFAS-C is a good and reliable tool for addictive-like behavior assessment

Non-invasive detection of hypovolemia or fluid responsiveness in spontaneously breathing subjects

Background: In the assessment of hypovolemia the value of functional hemodynamic monitoring during spontaneous breathing is debated. The aim of our study was to investigate in spontaneously breathing subjects the changes in hemodynamic parameters during graded central hypovolemia and to test whether slow patterned breathing improved the discriminative value of stroke volume (SV), pulse pressure (PP), and their variations (SVV, PPV). In addition, we tested the alterations in labial microcirculation. Methods: 20 healthy volunteers participated in our study. Central hypovolemia was induced by lower body negative pressure (LBNP). Continuous signals of ECG, non-invasive blood pressure and central venous pressure were recorded. During baseline and each stage of LBNP the labial microcirculation was investigated by orthogonal polarization spectral imaging, 3 minute periods of patterned breathing at 6 and 15/min respiratory rate were performed, and central venous blood gas analysis was done. Data from baseline and those of different LBNP levels were compared by analysis of variance and those of different breathing rates by t-test. Finally, we performed ROC analysis to assess the discriminative values of SV, PP, SVV and PPV. Results: Moderate central hypovolemia induced by LBNP caused significant, clinically relevant falls in PP (p < 0.05) and SV and central venous oxygen saturation (ScvO(2)) (p < 0.001). The proportion of perfused vessels (p < 0.001) and microvascular flow index decreased (p < 0.05). PPV increased (p < 0.001), however the magnitude of fluctuations was greater during slow patterned breathing (p < 0.001). SVV increased only during slow patterned breathing (p < 0.001). ROC analysis confirmed the best predictive value for SV (at 56 ml cut-off AUC 0.97, sensitivity 94%, specificity 95%). Slow patterned breathing improved the discriminative value of SVV (p = 0.0023). Conclusions: Functional hemodynamic monitoring with slow patterned breathing to control spontaneous respiration may be worthy for further study in different populations for the assessment of hypovolemia and the prediction of volume responsiveness