Efficacy Screening of Gloriosa Superba Extracts in a Murine Pancreatic Cancer Model Using (18)F-FDG PET/CT for Monitoring Treatment Response

Active Biomolecules from Vegetable Extracts with Antitumoral Activity against Pancreas Cancer: A Systematic Review (2011-2021)

The emergence of resistance to pancreatic cancer (PC) current treatment requires the development of new therapeutic strategies. In this context, bioactive molecules from plant extracts have shown excellent properties to improve classical therapy against this type of tumor. This systematic review aims to collect all the in vitro studies related to the antiproliferative activity of isolated plant molecules that support their applicability in PC. A total of 620 articles published in the last 10 years were identified, although only 28 were finally included to meet the inclusion criteria. Our results reflect the most important biomolecules from natural compounds that induce cell death in PC and their essential mechanism of cell death, including apoptosis, pathways activated by the KRAS mutation and cycle cell arrest, among others. These in vitro studies provide an excellent molecule guide showing applications against PC and that should be tested in vivo and in clinical trials to determine their usefulness to reduce PC incidence and to improve the prognosis of these patients. However, natural compounds are isolated in small amounts, which prevents comprehensive drug screening, being necessary the role of organic synthesis for the total synthesis of natural compounds or for the synthesis of their simplified and bioactive analogs.

Anticancer Secondary Metabolites: From Ethnopharmacology and Identification in Native Complexes to Biotechnological Studies in Species of Genus Astragalus L. and Gloriosa L

Some of the most effective anticancer compounds are still derived from plants since the chemical synthesis of chiral molecules is not economically efficient. Rapid discovery of lead compounds with pronounced biological activity is essential for the successful development of novel drug candidates. This work aims to present the chemical diversity of antitumor bioactive compounds and biotechnological approaches as alternative production and sustainable plant biodiversity conservation. Astragalus spp., (Fabaceae) and Gloriosa spp. (Liliaceae) are selected as research objects within this review because they are known for their anticancer activity, because they represent two of the largest families respectively in dicots and monocots, and also because many of the medicinally important plants are rare and endangered. We summarized the ethnobotanical data concerning their anticancer application, highlighted the diversity of their secondary metabolites possessing anticancer properties such as saponins, flavonoids, and alkaloids, and revealed the potential of the in vitro cultures as an alternative way of their production. Since the natural supply is limited, it is important to explore the possibility of employing plant cell or organ in vitro cultures for the biotechnological production of these compounds as an alternative.

Comparative LC-MS analysis of tropolone alkaloids from in vitro cultures and native sources of Gloriosa superba by Kendrick mass defect plots

INTRODUCTION

Gloriosa superba L. is a promising antitumoural plant species as a source of colchicinoids. Ethnobotanical applications of G. superba are associated with different plant parts such as leaves, seeds, fruits, tuber and the whole plant.

OBJECTIVES

A comparative phytochemical study of purified extracts from in vitro cultures and native tubers of G. superba was carried out by ultrahigh-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HR-MS) in combination with the mass defect filtering (MDF) technique.

MATERIAL AND METHODS

The individual compounds were tentatively annotated using database correlations, retention time (Rt), accurate m/z data obtained by electrospray ionisation (ESI) (+)-HR-MS, proposed elemental composition, ring double bond equivalent (RDBeq) values and HR-MS/MS fragmentation patterns. Moreover, the identification was based on transforming the exact mass ratio (m/z) for the protonated molecular ions [М + Н]⁺ of the observed metabolites in Kendrick nominal masses (NKMs) and calculation of the Kendrick mass defect (KMD), which made it possible to graphically present the ion peaks in Kendrick plots.

RESULTS

Building Kendrick plots allows easy differentiation of small structural differences such as methylation or demethylation of compounds from the same homologous series. In this way, a wide range of tropolone alkaloids was characterised. A greater variety was observed in in vitro cultures, compared to native sources.

CONCLUSION

This LC-MS analysis unambiguously demonstrated the presence of tropolone alkaloids in in vitro cultures of G. superba. This approach of LC-MS data interpretation can be used to understand complex mass spectra such as those of plant extracts.

Biotransformation to Produce the Anticancer Compound Colchicoside Using Cell Suspension Cultures of Astragalus vesicarius Plant Species

This paper discusses the biotechnological process affected by means of plant suspension cultures, for production of colchicoside, the 3- O-glucosyl derivative of 3- O-demethylcolchicine. Colchicoside can be considered as an antitumoural prodrug which is activated after oral administration and may have more beneficial effects and a better toxicity profile (because of a slow-release effect) than colchicine. We have developed a green and efficient biotechnological method using colchicine, as a precursor, derived from its natural source G. superba seeds. Plant suspension cultures of Astragalus vesicarius were used to design a practical biotechnological platform to replace a methyl group at C-3 regiospecifically by a glycosyl moiety in colchicine. Using different concentrations of a colchicine-rich extract, the maximum enzymatic potential of Astragalus vesicarius suspension cells was achieved. According to quantitative HPLC-UV analysis, levels of 9.35 μmol/g DW colchicoside were achieved. This is the first report of region-specific glycosylation at C-3 of the aromatic ring A of the colchicine using plant suspension cultures.

An HPLC Method for the Quantification of Colchicine and Colchicine Derivatives in Gloriosa superba seeds

An 80% ethanolic extract of Gloriosa superba L. seeds (glory lily, Colchicaceae), as well as a colchicine-poor/colchicoside-rich extract, were shown to exhibit antitumor activity in a murine model for pancreatic cancer. Phytochemical investigations of the 80% ethanolic extract led to the identification of colchicine, 3- O-demethylcolchicine, and colchicoside. The objective of this work was to develop and validate a high performance liquid chromatographic analytical method according to the ICH guidelines for the quantification of these constituents. The calibration model appeared to be linear, ranging from 2.1 μg/mL to 41.9 μg/mL. The method was shown to be precise with respect to time (RSD% of 3.1% for colchicine, 2.9% for 3- O-demethylcolchicine, and 4.7% for colchicoside, 3 days, n = 6) and with respect to the concentration (RSD% of 2.9% for colchicine, 3.0% for 3- O-demethylcolchicine and 4.1% for colchicoside, 3 levels, n = 6). The recovery of colchicine resulted in a mean recovery of 100.02% with a RSD% of 2.1%. The correction factors for colchicoside and 3- O-demethylcolchicine were determined as 1.94 and 1.20, respectively. The total amount of colchicine and colchicine derivatives found in the crude extract of G. superba was 4.6% (m/m) expressed as colchicine and the overall mean of colchicine found in the crude extract was 2.8% (m/m). By using the correction factors, the other constituents of the crude extract could also be quantified, and it was found to contain 1.5% (m/m) colchicoside and 1.3% (m/m) 3- O-demethylcolchicine.

Biorhizome: A Biosynthetic Platform for Colchicine Biomanufacturing

Colchicine is one of the oldest plant-based medicines used to treat gout and one of the most important alkaloid-based antimitotic drugs with anticancer potential, which is commercially extracted from Gloriosa superba. Clinical trials suggest that colchicine medication could prevent atrial fibrillation recurrence after cardiac surgery. In addition, therapeutic colchicine is undergoing clinical trials to treat non-diabetic metabolic syndrome and diabetic nephropathy. However, the industrial-scale biomanufacturing of colchicine have not yet been established. Clearly, further studies on detailed biorhizome-specific transcriptome analysis, gene expression, and candidate gene validation are required before uncover the mechanism of colchicine biosynthesis and biorhizome-based colchicine biomanufacturing. Annotation of 32312 assembled multiple-tissues transcripts of G. superba represented 15088 unigenes in known plant specific gene ontology. This could help understanding colchicine biosynthesis in G. superba. This review highlights the biorhizomes, rhizome specific genes or gene what expressed with high level in rhizomes, and deep fluid dynamics in a bioreactor specifically for the biomanufacture of colchicine.

Isolation and Structure Elucidation of Glucosylated Colchicinoids from the Seeds of Gloriosa superba by LC-DAD-SPE-NMR

Four new colchicinoids were isolated from the seeds of Gloriosa superba together with the known compounds colchicoside (4) and 3-de-O-methylcolchicine-3-O-β-d-glucopyranosyl-(1→4)-3-O-β-d-glucopyranoside (6), by means of conventional column chromatography and LC-DAD-SPE-NMR. The new compounds were identified as N-deacetyl-N-formyl-3-de-O-methylcolchicine-3-O-β-d-glucopyranoside (1), 3-de-O-methylcolchicine-3-O-β-d-glucopyranosyl-(1→6)-3-O-β-d-glucopyranoside (2), N-deacetyl-N-formyl-3-de-O-methylcolchicine-3-O-β-d-glucopyranosyl-(1→6)-3-O-β-d-glucopyranoside (3), and 3-de-O-methylcolchicine-3-O-β-d-glucopyranosyl-(1→3)-3-O-β-d-glucopyranoside (5). The structure elucidation was performed by means of NMR (COSY, HSQC, and HMBC), HRESIMS/MS, and GCMS data analysis.

Coadministration of a Gloriosa superba extract improves the in vivo antitumoural activity of gemcitabine in a murine pancreatic tumour model

BACKGROUND

Gloriosa superba L. (glory lily, Colchicaceae) contains colchicine, and related alkaloids such as 3-O-demethylcolchicine and its glycoside colchicoside. Previously the in vivo efficacy of a crude extract and a colchicine-poor / colchicoside-rich extract of G. superba seeds was shown in a murine model of pancreatic adenocarcinoma.

HYPOTHESIS/PURPOSE

The efficacy can be improved without obvious signs of toxicity by increasing the treatment dose; the efficacy of gemcitabine can be improved by coadministration of a Gloriosa superba extract.

STUDY DESIGN

A survival experiment was carried out in a murine model of pancreatic adenocarcinoma and the semi-long-term toxicity of both G. superba extracts was determined; a combination therapy with gemcitabine was evaluated.

METHODS

A crude ethanolic extract (GS) and a colchicine-poor / colchicoside-rich extract (GS2B) were prepared, containing 3.22% colchicine, 2.52% colchicoside and 1.52% 3-O-demethylcolchicine (GS), and 0.07%, 2.26% and 0.46% (m/m) (GS2B). They were evaluated in a murine model of pancreatic adenocarcinoma at a dose of 4.5mg/kg (p.o., daily) total content of colchicine and derivatives during 3 weeks, or at 3.0mg/kg (p.o., daily) combined with gemcitabine (60mg/kg, i.p., 3x/week) during 54 days.

RESULTS

A significant effect in tumour growth over time was observed for gemcitabine and the combination therapy compared to the control group. No significant difference was observed for the groups treated with colchicine and both extracts. However, combination therapy was significantly better than the monotherapy with gemcitabine. Moreover, survival analysis showed a significant prolongation of the survival of the groups treated with gemcitabine and the combination therapy. A slight difference in survival was observed between gemcitabine and the combination therapy, the latter one being slightly better. No significant prolongation of survival was observed for the extracts and colchicine compared to the control group.

CONCLUSION

Although a relevant tumour growth inhibition and a difference of relative tumour volume compared to the control group were observed on day 11, and a slightly longer survival was noticed for GS2B, the most important conclusion from this study is that the crude G. superba extract (GS) might have an added value combined with gemcitabine in the treatment of pancreatic tumours.