Antiproliferative Effect of Synadenium grantii Hook f. stems (Euphorbiaceae) and a Rare Phorbol Diterpene Ester

Chemical profiling and quality evaluation of raw and vinegar-processing frankincense by multiple UPLC-MS/MS techniques

INTRODUCTION

Frankincense is used for analgesic, tumor-suppressive, and anti-inflammatory treatments in Traditional Chinese Medicine but poses toxicological concerns. Vinegar processing is a common technique used to reduce the toxicity of frankincense.

OBJECTIVE

This study aimed to investigate the chemical composition and quality evaluation of raw and vinegar-processing frankincense by multiple UPLC-MS/MS techniques. Additionally, we purposed refining the vinegar processing technique and identifying potentially harmful ingredients in the raw frankincense.

METHODOLOGY

Sub-chronic oral toxicity studies were conducted on raw and vinegar-processing frankincense in rats. The composition of frankincense was identified by UPLC-Q-TOF-MS/MS. Chemometrics were used to differentiate between raw and vinegar-processing frankincense. Potential chemical markers were identified by selecting differential components, which were further exactly determined by UPLC-QQQ-MS/MS. Moreover, the viability of the HepG2 cells of those components with reduced contents after vinegar processing was assessed.

RESULTS

The toxicity of raw frankincense is attenuated by vinegar processing, among which vinegar-processing frankincense (R40) (herb weight: rice vinegar weight = 40:1) exhibited the lowest toxicity. A total of 83 components were identified from frankincense, including 40 triterpenoids, 37 diterpenoids, and 6 other types. The contents of six components decreased after vinegar-processing, with the lowest levels in R40. Three components, specifically 3α-acetoxy-11-keto-β-boswellic acid (AKBA), 3α-acetoxy-α-boswellic acid (α-ABA), and 3α-acetoxy-β-boswellic acid (β-ABA), inhibited the viability of HepG2 cells. The processing of frankincense with vinegar at a ratio of 40:1 could be an effective method of reducing the toxicity in raw frankincense.

CONCLUSION

Our research improves understanding of the toxic substance basis and facilitates future assessments of frankincense quality.

Tigliane Diterpenoids

The distribution, chemistry, and molecular bioactivity of tiglianes are reviewed from the very beginning of the studies on these diterpenoids, summarizing their clinical and toxicological literature mostly in its more recent and controversial aspects, and critically analyzing various proposals for their biosynthesis.

Nature's Green Potential: Anticancer Properties of Plants of the Euphorbiaceae Family

The number of cancer cases will reach 24 million in 2040, according to the International Agency for Research on Cancer. Current treatments for cancer are not effective and selective for most patients; for this reason, new anticancer drugs need to be developed and researched enough. There are potentially useful drugs for cancer isolated from plants that are being used in the clinic. Available information about phytochemistry, traditional uses, in vitro and in vivo experiments with plants, and pure compounds isolated from the Euphorbiaceae family indicates that this family of plants has the potential to develop anticancer drugs. This review examines selected species from the Euphorbiaceae family and their bioactive compounds that could have potential against different types of cancer cells. It reviews the activity of crude extracts, isolated compounds, and nanoparticles and the potential underlying mechanisms of action.

In Vitro Cytotoxic Study of Euphorbia grantii Oliv. Aerial Parts against MCF-7 and MCF-7ADR Breast Cancer Cell Lines: A Bioactivity-Guided Isolation

The development of highly efficient and low-toxicity anticancer drugs is one of the most critical problems in the medical field. Euphorbia grantii is commonly reported as an antiviral plant; a dilute solution of its latex is used for intestinal worms and to promote blood clotting and tissue healing. Our study evaluated the antiproliferative activity of the total extract, its respective fractions, and the isolated compounds from E. grantii aerial parts. A phytochemical study was done by several chromatographic methods, and the cytotoxic activity was assessed using the sulforhodamine B assay. The dichloromethane fraction (DCMF) exhibited promising cytotoxic activity against breast cancer cell lines (MCF-7 and MCF-7^ADR), with an IC₅₀ of 10.31 and 10.41 μg/mL, respectively. Chromatographic purification of the active fraction revealed the isolation of eight compounds. Among the isolated compounds, euphylbenzoate (EB) exhibited a promising effect with an IC₅₀ of 6.07 and 6.54 μM against MCF-7 and MCF-7^ADR, respectively, while other compounds showed no activity. Euphol, cycloartenyl acetate, cycloartenol, and epifriedelinyl acetate showed moderate activity (33.27-40.44 μM). Euphylbenzoate has smartly tackled both apoptosis and autophagy programmed cell death mechanisms. These results demonstrated that E. grantii aerial parts yield active compounds with significant antiproliferative potential.

Identification of Daphne genkwa and Its Vinegar-Processed Products by Ultraperformance Liquid Chromatography-Quadrupole Time-of-Flight Mass Spectrometry and Chemometrics

Crude herbs of Daphne genkwa (CHDG) are often used in traditional Chinese medicine to treat scabies baldness, carbuncles, and chilblain owing to their significant purgation and curative effects. The most common technique for processing DG involves the use of vinegar to reduce the toxicity of CHDG and enhance its clinical efficacy. Vinegar-processed DG (VPDG) is used as an internal medicine to treat chest and abdominal water accumulation, phlegm accumulation, asthma, and constipation, among other diseases. In this study, the changes in the chemical composition of CHDG after vinegar processing and the inner components of the changed curative effects were elucidated using optimized ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). Untargeted metabolomics, based on multivariate statistical analyses, was also used to profile differences between CHDG and VPDG. Eight marker compounds were identified using orthogonal partial least-squares discrimination analysis, which indicated significant differences between CHDG and VPDG. The concentrations of apigenin-7-O-β-d-methylglucuronate and hydroxygenkwanin were considerably higher in VPDG than those in CHDG, whereas the amounts of caffeic acid, quercetin, tiliroside, naringenin, genkwanines O, and orthobenzoate 2 were significantly lower. The obtained results can indicate the transformation mechanisms of certain changed compounds. To the best of our knowledge, this study is the first to employ mass spectrometry to detect the marker components of CHDG and VPDG.

Bioactive Secondary Plant Metabolites from Euphorbia umbellata (PAX) BRUYNS (Euphorbiaceae)

The species Euphorbia umbellata has been used to treat inflammatory diseases, cancer, and ulcers. Biological activities reported in the literature, including antiproliferative, cytotoxic and anti-inflammatory, are attributed to the chemical constituents present in its composition as terpenes and polyphenolic compounds. The most recurrently verified metabolites in the Euphorbiaceae family plant species are terpenes, of which euphol is a major constituent with broadly reported cytotoxic, antinociceptive and anti-inflammatory effects; it frequently appears in various extracts obtained from the plant. Euphol has a documented inhibitory effect on neutrophil chemotaxis and can modulate the complement system. Since complement system activation is intimately intertwined with autoimmune and inflammatory diseases, tumor growth promotion and metastasis, plant metabolites from Euphorbia umbellata might influence the outcomes of inflammatory processes. We believe that this is the first review presenting the current knowledge on Euphorbia umbellata secondary metabolites and their biological activities.

The Natural Products and Extracts: Anti-Triple-Negative Breast Cancer in Vitro

Triple-negative breast cancer (TNBC) makes up 15 % to 20 % of all breast cancer (BC) cases, and represents one of the most challenging malignancies to treat. For many years, chemotherapy has been the main treatment option for TNBC. Natural products isolated from marine organisms and terrestrial organisms with great structural diversity and high biochemical specificity form a compound library for the assessment and discovery of new drugs. In this review, we mainly focused on natural compounds and extracts (from marine and terrestrial environments) with strong anti-TNBC activities (IC₅₀ <100 μM) and their possible mechanisms reported in the past six years (2015-2021).

Effects of the Latex of Synadenium grantii Hook F. (Euphorbiaceae) on a Preclinical Model of Canine Prostate Cancer

Prostatic cancer (PC) stands out in terms of its occurrence, pathophysiology, and unfavorable prognostics in humans and dogs. Natural drugs bear an integrative potential for conventional antineoplastic treatments. In this context, the bioproducts of Synadenium grantii have been empirically used in different parts of Brazil for the integrative treatment of prostate cancer in humans. However, there is no availability of scientific evidence of the antitumor effects of S. grantii. Therefore, this study aimed to investigate the bioactive compounds in the latex of S. grantii using the high-resolution mass spectrophotometry (HRMS) and to evaluate its cytotoxic effects on primary canine PC cell cultures. Four fragments of phorbol ester were identified as potential bioactive compounds using the HRMS. With the help of an MTT ([3-(4,5-dimethyldiazol-2-yl)-2,5 diphenyltetrazolium bromide]) assay, two canine prostatic carcinoma cell lines (PC 1 and PC2) showed a decrease in the tumor cell count, with an Inhibitory concentration 50 (IC50)of 0.8469 and 0.6068 mg/ml, respectively, for PC1 and PC2. In conclusion, the latex of S. grantii contains phorbol esters in its composition, and its aqueous solution has a cytotoxic effect on canine metastatic PC cells in vitro.

Toxicological and anti-inflammatory profile of Synadenium grantii Hook. f. in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Synadenium grantii Hook. f., popularly known as "janaúba" or "leiterinha", is used in the folk medicine to treat gastric disorders, some types of neoplasias and inflammatory diseases.

AIM OF THE STUDY

The aim of this study was to show the anti-inflammatory activity of the methanol extract obtained from S. grantii stems and also certify the safety of the extract performing toxicological analysis.

MATERIAL AND METHODS

The anti-inflammatory activity was investigated using carrageenan-induced inflammation in the subcutaneous tissue of male Swiss mice orally pre-treated with the S. grantii extract (1, 3 or 10 mg/kg). The leukocyte influx (optical microscopy) and secretion of chemical mediators (TNF, IL-6 and IL-1β, by enzyme-linked immunosorbent assay) were quantified in the inflamed exudate. The toxicity was investigated using the dose-fixed procedure (acute toxicity) and repeated dose 28-day (subacute toxicity) in mice orally treated with S. grantii extract. The open field and rota-rod test were used to evaluate possible interference of adverse effect of S. grantii on motor coordination, locomotor and exploratory activity.

RESULTS

The analysis of the inflammatory exudate of S. grantii-treated mice demonstrated reduction in the polymorphonuclear cells (PMN) migration to the inflamed tissue, as well as the reduction of the pro-inflammatory cytokines TNF and IL-1β. Furthermore, the acute and sub-acute toxicity studies did not show significant changes in body weight, general behaviour, biochemical parameters, organ weight and liver and kidney histopathological analysis. However, animals acutely treated with S. grantii presented reduction in the number of crosses in relation to the vehicle group, without significant difference in the number of elevations and latency time between the groups in rota-rod test. The obtained results allow to set the NOAEL (Non-observed-adverse-effect level) in 100 mg/kg for this specie of rodent.

CONCLUSIONS

Together, the results herein obtained show that S. grantii extract presented anti-inflammatory activity by decreasing the influx of PMN to the inflamed tissue, as well as the cytokines TNF and IL-1β levels. In addition, S. grantii extract seemed not to present significant acute or subacute toxicity when administered to mice, demonstrating for the first time the safety of this extract, when orally administered.

Reactivation of latent HIV-1 in vitro using an ethanolic extract from Euphorbia umbellata (Euphorbiaceae) latex

Euphorbia umbellata (E. umbellata) belongs to Euphorbiaceae family, popularly known as Janauba, and its latex contains a combination of phorbol esters with biological activities described to different cellular protein kinase C (PKC) isoforms. Here, we identified deoxi-phorbol esters present in E. umbellata latex alcoholic extract that are able to increase HIV transcription and reactivate virus from latency models. This activity is probably mediated by NF-kB activation followed by nuclear translocation and binding to the HIV LTR promoter. In addition, E. umbellata latex extract induced the production of pro inflammatory cytokines in vitro in human PBMC cultures. This latex extract also activates latent virus in human PBMCs isolated from HIV positive patients as well as latent SIV in non-human primate primary CD4+ T lymphocytes. Together, these results indicate that the phorbol esters present in E. umbellata latex are promising candidate compounds for future clinical trials for shock and kill therapies to promote HIV cure and eradication.