RESUMO
The INFOGEST protocol has been widely used as a static in-vitro simulation of gastrointestinal food digestion for bioaccessibility assessments on bioactive compounds. The standardization of the activity of several enzymes, such as pepsin, via UV-spectrophotometry of digested hemoglobin at 280 nm is a key step in the protocol. Standardization is a crucial stage since it is necessary to determine the quantity of enzyme to be added to the sample for digestion. However, this method is yet to be analytically validated; it requires quartz cuvettes and large volumes of samples and is time-consuming. Thus, we reviewed and adapted a well-known colorimetric method in microplates array by using the Folin-Ciocalteu reagent, and this study is the first to report for miniaturization of this method, the advantages of which include its automation, ease of use, the low volume of samples required, the minimal use of reagents, and speed. This method was compared to the traditional UV method, and the comparison results show no statistical difference between the inter day means for each group (p > 0.05). The proposed method was validated, showing high reproducibility (8% as inter-day CV) and statistically comparable results with the traditional UV spectrophotometric method.
RESUMO
Colorectal cancer (CRC) is the third most revalent type of cancer in the world and the second most common cause of cancer death (about 1 million per year). Historically, natural compounds and their structural analogues have contributed to the development of new drugs useful in the treatment of various diseases, including cancer. Essential oils are natural odorous products made up of a complex mixture of low molecular weight compounds with recognized biological and pharmacological properties investigated also for the prevention and treatment of cancer. The aim of this paper is to highlight the possible role of essential oils in CRC, their composition and the preclinical studies involving them. It has been reviewed the preclinical pharmacological studies to determine the experimental models used and the anticancer potential mechanisms of action of natural essential oils in CRC. Searches were performed in the following databases PubMed/Medline, Web of science, TRIP database, Scopus, Google Scholar using appropriate MeSH terms. The results of analyzed studies showed that EOs exhibited a wide range of bioactive effects like cytotoxicity, antiproliferative, and antimetastatic effects on cancer cells through various mechanisms of action. This updated review provides a better quality of scientific evidence for the efficacy of EOs as chemotherapeutic/chemopreventive agents in CRC. Future translational clinical studies are needed to establish the effective dose in humans as well as the most suitable route of administration for maximum bioavailability and efficacy. Given the positive anticancer results obtained from preclinical pharmacological studies, EOs can be considered efficient complementary therapies in chemotherapy in CRC.
RESUMO
Thymoquinone (TQ) is a secondary metabolite found in abundance in very few plant species including Nigella sativa L., Monarda fistulosa L., Thymus vulgaris L. and Satureja montana L. Preclinical pharmacological studies have shown that TQ has many biological activities, such as anti-inflammatory, antioxidant and anticancer. Both in vivo and in vitro experiments have shown that TQ acts as an antitumor agent by altering cell cycle progression, inhibiting cell proliferation, stimulating apoptosis, inhibiting angiogenesis, reducing metastasis and affecting autophagy. In this comprehensive study, the evidence on the pharmacological potential of TQ on pancreatic cancer is reviewed. The positive results of preclinical studies support the view that TQ can be considered as an additional therapeutic agent against pancreatic cancer. The possibilities of success for this compound in human medicine should be further explored through clinical trials.