Antiproliferative potential of essential oil from the leaves of Croton floribundus (Euphorbiaceae) against human metastatic melanoma cell lines.

Melanoma is a cancer type with high lethality, metastatic capacity, and limited therapeutic options. Different essential oils have been reported with antitumoral potential.  Thus, the essential oil (EO) of the leaves of C. floribundus was obtained by hydrodistillation and analyzed by GC-MS. The majority of substances annotated were ß-selinene, E-Caryophyllene, and Premnaspirodiene. The cytotoxic activity of EO was evaluated on three melanoma cell lines SKMEL-147, WM-1366, and CHL-1, which are representative of metastatic melanoma with different mutation profiles. The IC50 values found for EO were lower than temozolomide (reference drug) in all melanoma cell lines. In addition, the selectivity of EO was upward when compared to the reference drug. Interestingly, the WM-1366 cell line was the most responsive, and these findings are very promising considering that it has shown high resistance to the plethora of compounds. Thus,  the C. floribundus EO is a promising source to drive further studies for the development of new treatments for metastatic melanoma, which is urgently relevant given the resistance of this pathology to current treatments.

Chemical annotation of the infusion of Jungia floribunda Less and its inhibitory potential on the elastase enzyme.

Jungia floribunda Less. is a shrub belonging to the Asteraceae. The infusion of its leaves has been used, in folk medicine of several South American countries, as anti-inflammatory and hypoglycaemic agent. In the present study, the infusion of leaves from J. floribunda was obtained and its chemical composition was determined by UHPLC-MS associated with molecular network allowing the annotation of flavonoids, sesquiterpene lactones, coumarins, and chlorogenic acid derivatives. Besides, in vitro elastase activity assay was carried out with the infusion. As observed, elastase was inhibited at concentrations ranging from 15 to 240 µg/mL, reaching to 71% of inhibition at the maximum of evaluated concentration. Given that species of plants are promising sources for the discovery of new drugs, these results corroborate the infusion of J. floribunda as a potential source of bioactive compounds for the discovery of new inhibitors for elastase, besides its ethnopharmacological aspects.

Potential anti-inflammatory biomarkers from Myrtaceae essential oils revealed by untargeted metabolomics.

Many species from Myrtaceae have traditionally been used in traditional medicine as anti-inflammatory, antimicrobial, antidiarrheal, antioxidant and antirheumatic, besides in blood cholesterol reduction. In the present work, the anti-inflammatory activity of essential oils from eighteen Myrtaceae spp. were evaluated according to their ex-vivo anti-inflammatory activity in human blood, and the corresponding biomarkers were determined using untargeted metabolomics data and multivariate data analysis. From these studied species, six displayed anti-inflammatory activity with percentage rates of inhibition of PGE2 release above 70%. Caryophyllene oxide (1), humulene epoxide II (2), ß-selinene (3), α-amorphene (4), α-selinene (5), germacrene A (6), ß-bisabolene (7), α-muurolene (8), α-humulene (9), ß-gurjunene (10), myrcene (11), ß-elemene (12), α-cadinol (13), α-copaene (14), E-nerolidol (15) and ledol (16) were annotated as potential anti-inflammatory biomarkers. The results obtained in this study point to essential oils from species of the Myrtaceae family as a rich source of anti-inflammatory agents.

Anti-Inflammatory Activity of Lauraceae Plant Species and Prediction Models Based on Their Metabolomics Profiling Data.

The Lauraceae is a botanical family known for its anti-inflammatory potential. However, several species have not yet been studied. Thus, this work aimed to screen the anti-inflammatory activity of this plant family and to build statistical prediction models. The methodology was based on the statistical analysis of high-resolution liquid chromatography coupled with mass spectrometry data and the ex vivo anti-inflammatory activity of plant extracts. The ex vivo results demonstrated significant anti-inflammatory activity for several of these plants for the first time. The sample data were applied to build anti-inflammatory activity prediction models, including the partial least square acquired, artificial neural network, and stochastic gradient descent, which showed adequate fitting and predictive performance. Key anti-inflammatory markers, such as aporphine and benzylisoquinoline alkaloids were annotated with confidence level 2. Additionally, the validated prediction models proved to be useful for predicting active extracts using metabolomics data and studying their most bioactive metabolites.

Alkaloids derived from flowers of Senna spectabilis, (-)-cassine and (-)-spectaline, have antiproliferative activity on HepG2 cells for inducing cell cycle arrest in G1/S transition through ERK inactivation and downregulation of cyclin D1 expression.

Cancer is one of the most critical problems of public health in the world and one of the main challenges for medicine in this century. Unfortunately, most patients are diagnosed at advanced stage, when the treatment options are palliative. Consequently, the search for novel therapeutic options is imperative. In the context, the plants represent an important source for discovering of novel compounds with pharmacological potential including antineoplastic agents. Herein, we aimed to investigate in vitro antiproliferative and cytotoxic potentials of an alkaloid mixture derived from Senna spectabilis, (−)-cassine (1) and (−)-spectaline (2). These alkaloids reduced cell viability in a concentration-dependent manner of six tumor cell lines. From initial screening, HepG2 cells were selected for further investigations. We show that alkaloids 1/2 have an important antiproliferative activity on HepG2 cells due to their ability in inducing cell cycle arrest in G1/S transition. This effect was associated to ERK inactivation and down-regulation of cyclin D1 expression. In addition, we evidenced a disruption of the microfilaments and microtubules in a consequence of the treatment. Taken together, the data showed by the first time that alkaloids 1/2 strongly inhibit cell proliferation of hepatocellular carcinoma cells. Therefore, they represent promise antitumor compounds against liver cancer and should be considered for further anticancer in vivo studies.