Anti-inflammatory and antinociceptive effects of a pectinolide-enriched fraction from Mesosphaerum pectinatum (L.) Kuntze

ETHNOPHARMACOLOGICAL RELEVANCE

Mesosphaerum pectinatum (L.) Kuntze (Lamiaceae), also known as sambacaitá, is a medicinal plant widely used in northeastern Brazil for the treatment of inflammatory and painful conditions, bacterial infections and cancer. Hence, the medicinal use of this species is quite meaningful to the search for bioactive compounds.

AIM OF THE STUDY

To evaluate the antinociceptive and anti-inflammatory activities of the pectinolide-enriched fraction of Mesosphaerum pectinatum (PEF) in animal models.

MATERIALS AND METHODS

The PEF was analyzed with HPLC-DAD and ¹H and ¹³C NMR. After the analysis, compounds of the pectinolide class were detected as major constituents in this fraction. The PEF (50, 100 and 200 mg/kg, p.o.) and the reference drugs - morphine (3.0 mg/kg, p.o.) and dexamethasone (2.0 mg/kg, p.o.) - were evaluated using models for nociception (hot plate, formalin-induced licking response) or inflammation (carrageenan-induced peritonitis and ear edema model).

RESULTS

The PEF significantly decreased the licking time of the animals treated when compared to the control group (second phase). In the carrageenan-induced peritonitis model, PEF (100 and 200 mg/kg) significantly decreased total and differential leukocyte counts. The PEF (0.3, 1.0 and 3.0 mg/ear) significantly reduced mice ear edema at the same extent and like the results obtained with the standard drug (dexamethasone). The MPO activity was reduced in mice ear at doses of 1 and 3 mg/ear. Antinociceptive effect on the hot plate test was not observed, demonstrating that there is no analgesic activity.

CONCLUSION

Our results suggest that the pectinolide-enriched fraction exhibits anti-inflammatory effects and that it is involved with inhibiting the release of the inflammatory mediators.

[6]-Gingerol-Derived Semi-Synthetic Compound SSi6 Inhibits Tumor Growth and Metastatic Dissemination in Triple-Negative Breast Cancer Xenograft Models

Simple Summary

Triple-negative breast cancers (TNBC) represent approximately 15% of all breast cancers and lack the expression of a defined molecular target. This absence makes this subtype of cancer difficult to treat and control. Current chemotherapy drugs cause various side effects and toxicities that can jeopardize the quality of life of patients with TNBC cancer. Therefore, this research focuses on a new semi-synthetic compound derived from [6]-gingerol, where we demonstrate that it does not cause significant toxic effects in vivo and, more importantly, we demonstrate its antitumor and antimetastatic effects using preclinical xenograft models simulating two clinical scenarios of a woman with breast cancer.

Abstract

Breast cancer metastasis is the most common cause of cancer death in women worldwide. Triple-negative breast cancers (TNBC) form a heterogeneous group of tumors that have higher relapse rates and poorer survival compared to other breast cancer subtypes. Thus, this work reports the antitumor and antimetastatic activities of a [6]-gingerol-derived semi-synthetic compound named SSi6 on MDA-MB-231 TNBC cells using xenograft models. SSi6 did not cause toxic effects in vivo as demonstrated by body weight and hematological and histological evaluations. From the orthotopic xenograft model, we demonstrated that SSi6 slows and inhibits the growth of the primary tumor, as well as prevents metastatic spontaneous progression from lymph nodes to the lungs. Moreover, a second xenograft model with resection of the primary tumor showed that SSi6 also blocks the progression of metastases from the lymph nodes to other visceral organs. Taken together, our results demonstrate that SSi6 is a promising compound to be investigated in other preclinical and clinical models to be applied as a complementary therapy for TNBC.

Gingerol suppresses sepsis-induced acute kidney injury by modulating methylsulfonylmethane and dimethylamine production

Acute kidney injury (AKI) and metabolic dysfunction are critical complications in sepsis syndrome; however, their pathophysiological mechanisms remain poorly understood. Therefore, we evaluated whether the pharmacological properties of 6-gingerol (6G) and 10-gingerol (10G) could modulate AKI and metabolic disruption in a rat model of sepsis (faecal peritonitis). Animals from the sham and AKI groups were intraperitoneally injected with 6G or 10G (25 mg/kg). Septic AKI decreased creatinine clearance and renal antioxidant activity, but enhanced oxidative stress and the renal mRNA levels of tumour necrosis factor-α, interleukin-1β, and transforming growth factor-β. Both phenol compounds repaired kidney function through antioxidant activity related to decreased oxidative/nitrosative stress and proinflammatory cytokines. Metabolomics analysis indicated different metabolic profiles for the sham surgery group, caecal ligation and puncture model alone group, and sepsis groups treated with gingerols. ¹H nuclear magnetic resonance analysis detected important increases in urinary creatine, allantoin, and dimethylglycine levels in septic rats. However, dimethylamine and methylsulfonylmethane metabolites were more frequently detected in septic animals treated with 6G or 10G, and were associated with increased survival of septic animals. Gingerols attenuated septic AKI by decreasing renal disturbances, oxidative stress, and inflammatory response through a mechanism possibly correlated with increased production of dimethylamine and methylsulfonylmethane.

Abstract A53: [10]-gingerol interferes with the adhesion of MDA-MB-231 tumor cells to extracellular matrix

Breast cancer is one of the most common malignant diseases in women worldwide. In developing countries, it is the second highest cause of death in women. Triple-negative breast cancer (TNBC) represents the approximately 15% of breast cancers that lack expression of estrogen (ER) and progesterone receptors (PR) and do not exhibit amplification of the human epidermal growth factor receptor 2 (HER2) gene. Metastatic process is described as a cascade of events. Normal cells are transformed into tumor cells due to mutations in genes that regulate critical pathways, producing an imbalance between proliferation and cell death that eventually leads to the formation of a primary tumor. Further interactions with the stromal microenvironment surrounding tumor cells and extracellular matrix (ECM) proteins contribute to the formation of new vessels. These interactions facilitate tumor cell invasion of surrounding tissues, intravasation through newly formed vessels, and dissemination to other tissues, to form secondary tumors. To treat metastasis from breast and many other cancer types, chemotherapy is one of the most extensively used methods. However, its efficacy and safety remain a primary concern, as well as its toxicity and other side effects. Thus, there is increasing interest in naturally occurring cancer antitumor agents. Ginger (Zingiber officinale Roscoe) is widely used worldwide as a food, spice, and herb. Recently we have demonstrated that [10]-gingerol is able to revert malignant phenotype in breast cancer cells in 3D culture and, moreover, to inhibit the dissemination of TNBC to multiple organs including to lung, bone, and brain, in spontaneous and experimental in vivo metastasis assays. The aim of this work was to investigate the effects of [10]-gingerol on the adhesion properties of MDA-MB-231 cells to the extracellular matrix (ECM). We hypothesized that, at least in part, these effects are mediated through [10]-gingerol interactions with αVβ3 integrin. Human MDA-MB-231 breast tumor cells were obtained from ATCC and maintained at 37°C, 5% CO2 in Dulbecco’s Modified Eagle Medium, containing FBS 10%). Ninety-six well plates were coated vitronectin (1µg/well) dissolved in adhesion buffer at 4ºC overnight, blocked for 2h with 1% BSA, and the wells washed with 100μL of adhesion buffer. MDA-MB-231 cells (5x105/mL) were pretreated for 30min with [10]-gingerol (1-100μM) in a humidified incubator with 5% CO2 at 37°C and 100µL of cell suspension plated into wells and incubated as above for a further 1 hour. Nonadherent cells were gently removed by washing and adherent cells were fixed with 100µl of 4% paraformaldehyde solution for 20min, stopped with PBS-Glycine, stained with DAPI, and counted in a HCS microscope. Data from docking were analyzed in AutoDock plugin for PyMOL and the two-dimensional scheme of interaction was obtained by LiPlot+.The electrochemical study of the interaction between [10]-gingerol and αVβ3 integrin was performed using disposable electrochemical cells (DCell), which are composed by a carbon working electrode, an Ag|AgCl pseudo-reference electrode, and a carbon counter electrode. Measurements were carried out employing the potentiostat DropSens 8000 and Dropview software 8400. The interaction of [10]-gingerol and αVβ3 integrin was evaluated by the changes in the [10]-gingerol electrochemical responses. For this, different amounts of standard αVβ3 integrin solution in PBS pH 7.0 were added and mixed homogeneously with a solution composed of 10µM [10]-gingerol. The differences of peak current were used to demonstrate the changes of electrochemical responses. We found that [10]-gingerol was able to inhibit TNBC cell adhesion to vitronectin ECM with more specificity compared to the other ECM components investigated, demonstrating that this compound interferes in this step of the metastatic process. We proposed that these effects could be, at least in part, resulting from the interaction between [10]-gingerol and αVβ3 integrin, as demonstrated by electrochemical and docking studies.

Citation Format: Angelina Maria Fuzer, Ana Carolina B. M. Martin, Rebeka Tomasin, Carolina Venturini Uliana, Amanda Blanque Becceneri, Rafael L. Bressani Lino, James Almada da Silva, Paulo Cezar Vieira, Heloisa Sobreiro Selistre de Araújo, Rodolpho de Campos Braga, Ronaldo Censi Faria, Marcia Regina Cominetti. [10]-gingerol interferes with the adhesion of MDA-MB-231 tumor cells to extracellular matrix [abstract]. In: Proceedings of the AACR Special Conference: Advances in Breast Cancer Research; 2017 Oct 7-10; Hollywood, CA. Philadelphia (PA): AACR; Mol Cancer Res 2018;16(8_Suppl):Abstract nr A53.

[10]-gingerol induces apoptosis and inhibits metastatic dissemination of triple negative breast cancer in vivo

There is increasing interest in the use of non-toxic natural products for the treatment of various pathologies, including cancer. In particular, biologically active constituents of the ginger oleoresin (Zingiber officinale Roscoe) have been shown to mediate anti-tumour activity and to contribute to the anti-inflammatory, antioxidant, antimicrobial, and antiemetic properties of ginger. Here we report on the inhibitory properties of [10]-gingerol against metastatic triple negative breast cancer (TNBC) in vitro and in vivo. We show that [10]-gingerol concentration-dependently induces apoptotic death in mouse and human TNBC cell lines in vitro. In addition, [10]-gingerol is well tolerated in vivo, induces a marked increase in caspase-3 activation and inhibits orthotopic tumour growth in a syngeneic mouse model of spontaneous breast cancer metastasis. Importantly, using both spontaneous and experimental metastasis assays, we show for the first time that [10]-gingerol significantly inhibits metastasis to multiple organs including lung, bone and brain. Remarkably, inhibition of brain metastasis was observed even when treatment was initiated after surgical removal of the primary tumour. Taken together, these results indicate that [10]-gingerol may be a safe and useful complementary therapy for the treatment of metastatic breast cancer and warrant further investigation of its efficacy, either alone or in combination with standard systemic therapies, in pre-clinical models of metastatic breast cancer and in patients.

Synthetic chalcone derivatives as inhibitors of cathepsins K and B, and their cytotoxic evaluation

A series of chalcone derivatives, 1-15, were prepared by Claisen-Schmidt condensation and evaluated for their cytotoxicities on tumor cell lines and also against proteolytic enzymes such as cathepsins B and K. Of the compounds synthesized, (E)-3-(3,4-dimethoxyphenyl)-1-phenylprop-2-en-1-one (12), (E)-3-(4-chlorophenyl)-1-phenylprop-2-en-1-one (13), (E)-3-(4-methoxyphenyl)-1-phenylprop-2-en-1-one (14), and (E)-3-(4-nitrophenyl)-1-phenylprop-2-en-1-one (15) showed significant cytotoxicities. The most effective compound was 15, which showed high cytotoxic activity with an IC50 value lower than 1 μg/ml, and no selectivity on the tumor cells evaluated. Substituents at C(4) of ring B were found to be essential for cytotoxicity. In addition, it was also demonstrated that some of these chalcones are moderate inhibitors of cathepsin K and have no activity against cathepsin B.

Purification and differential biological effects of ginger-derived substances on normal and tumor cell lines

This study describes an optimization of [6]-, [8]- and [10]-gingerol isolation and purification in semi-preparative HPLC scale and their anti-proliferative activity. The gingerols purification was carried out in HPLC system using a Luna-C₁₈ and the best mobile phase evaluated was MeOH/H₂O (75:25, v/v). This new methodology for the gingerols isolation was very effective, since considerable amounts (in the range of milligrams) with a good purity degree (∼98%) were achieved in 30 min of chromatographic run. [6]-, [8]- and [10]-Gingerol purified by this methodology inhibited the proliferation of MDA-MB-231 tumor cell line with IC₅₀ of 666.2±134.6 μM, 135.6±22.6 μM and 12.1±0.3 μM, respectively. These substances also inhibited human fibroblasts (HF) cell proliferation, however in concentrations starting from 500 μM. In conclusion, our results demonstrate an optimization of gingerols isolation and their specific anti-proliferative activities against tumor cells, suggesting their use as important models for drug design in an attempt to develop new compounds with fewer side effects when compared to conventional chemotherapy.