RESUMO
Cancer is one of the leading causes of death globally. The development of drug resistance is the main contributor to cancer-related mortality. Cancer cells exploit multiple mechanisms to reduce the therapeutic effects of anticancer drugs, thereby causing chemotherapy failure. Natural products are accessible, inexpensive, and less toxic sources of chemotherapeutic agents. Additionally, they have multiple mechanisms of action to inhibit various targets involved in the development of drug resistance. In this review, we have summarized the basic research and clinical applications of natural products as possible inhibitors for drug resistance in cancer. The molecular targets and the mechanisms of action of each natural product are also explained. Diverse drug resistance biomarkers were sensitive to natural products. P-glycoprotein and breast cancer resistance protein can be targeted by a large number of natural products. On the other hand, protein kinase C and topoisomerases were less sensitive to most of the studied natural products. The studies discussed in this review will provide a solid ground for scientists to explore the possible use of natural products in combination anticancer therapies to overcome drug resistance by targeting multiple drug resistance mechanisms.
RESUMO
PURPOSE: Studies on the effect of body weight and coffee consumption on leptin, vitamin B12, and folic acid are scarce and conflicting. This study investigates the effect of body weight and/or coffee consumption rate on the serum levels of these molecules in healthy young adult males. PATIENTS AND METHODS: This observational cross-sectional study was carried out at the faculty of pharmacy, Applied Science Private University (ASU), Amman, Jordan, from July to September 2020. Young healthy males were invited to participate in the study and fill a questionnaire regarding lifestyle habits including coffee consumption during the last 3 months, medical history, and anthropometric measurements. Depending on BMI and extent of coffee consumption, participants were divided into 4 groups; normal body weight and moderate coffee consumption (NW/MCC) group; normal body weight and heavy coffee consumption (NW/HCC) group; overweight and moderate coffee consumption (OW/MCC) group; overweight and heavy coffee consumption (OW/HCC) group. Serum samples were taken to measure leptin, vitamin B12, and folic acid levels in addition to morning and midnight salivary cortisol and dehydroepiandrosterone (DHEA) samples. RESULTS: Healthy males (n = 122) aged 18 to 26 years continued participation in this study. Serum levels of leptin in NW/MCC, NW/HCC, OW/MCC, OW/HCC groups were 5.93, 5.75, 14.86, 16.79 ng/mL, respectively. Serum levels of vitamin B12 in these groups were 356.09, 402.71, 334.25, 331.05 pg/mL, respectively. While, the serum levels of folic acid were 8.92, 10.27, 10.12, 10.47 ng/mL, respectively. Body weight was positively associated with leptin (p = 0.00), negatively associated with vitamin B12 (p = 0.047), and not associated with folic acid (p = 0.235). Coffee consumption rate had no significant effect on leptin, vitamin B12, or folic acid. Finally, the combination of body weight and coffee consumption had no significant effect on leptin, vitamin B12, or folic acid. CONCLUSION: There was no possible synergistic effect between body weight and coffee consumption rate on leptin, vitamin B12, or folic acid levels. However, overweight was associated with higher leptin, lower vitamin B12, and no change in folic acid levels. TRIAL REGISTRATION: This trial was registered at clinicaltrials.gov as NCT04488731.
RESUMO
Sleep deprivation is a common health problem that is growing rapidly worldwide and it is associated with short- and long-term impacts on health. The aim of this study was to detect potential predictors of salivary testosterone (sT) association with sleep deprivation in Arab male university students. In this prospective cohort study, 77 university male students in the age range of 18 to 26 years were divided into two groups, sleep-deprived (SD) participants and non-sleep-deprived (NSD) participants. Sleep deprivation was defined as sleeping less than 5 hr per night. Blood samples and sT were collected from fasting participants to measure serum levels of glucose, lipid profile, leptin, serotonin, sT, and body mass index (BMI) values. The multiple linear correlation model of high-density lipoprotein cholesterol (HDL-C), BMI, and serotonin was positively correlated with sT ( r = .977, p < .05) in the SD group. No correlations were identified with sT in the NSD group. In the SD study group, the multiple linear regression model of HDL-C, BMI, and serotonin was significantly influenced by sT ( R² = .955, p < .05). These predictors together explained approximately 96% of the variance in sT levels in the SD study group. No predictive variables for sT were reported in the NSD group. Results indirectly confirmed the presence of a positive association between sT and sleep deprivation in young men. This association is mediated by three factors, HDL-C, BMI, and serum serotonin, which are collectively considered as part of a significant physiological adaptation to sleep deprivation in young men.
