A triterpenoid from wild bitter gourd inhibits breast cancer cells

The Role of Bitter Melon in Breast and Gynecological Cancer Prevention and Therapy

Phytotherapy has long represented a widely accepted treatment alternative to conventional therapy. Bitter melon is a vine with potent antitumor effects against numerous cancer entities. To date, no review article has, however, been published on the role of bitter melon in breast and gynecological cancer prevention and therapy. The current work constitutes the most comprehensive, up-to-date review of the literature, which highlights the promising anticancer effects of bitter melon on breast, ovarian, and cervical cancer cells and discusses future research recommendations.

Biopolymeric nanoparticles based effective delivery of bioactive compounds toward the sustainable development of anticancerous therapeutics

Nowadays, effective cancer therapy is a global concern, and recent advances in nanomedicine are crucial. Cancer is one of the major fatal diseases and a leading cause of death globally. Nanotechnology provides rapidly evolving delivery systems in science for treating diseases in a site-specific manner using natural bioactive compounds, which are gaining widespread attention. Nanotechnology combined with bioactives is a very appealing and relatively new area in cancer treatment. Natural bioactive compounds have the potential to be employed as a chemotherapeutic agent in the treatment of cancer, in addition to their nutritional benefits. Alginate, pullulan, cellulose, polylactic acid, chitosan, and other biopolymers have been effectively used in the delivery of therapeutics to a specific site. Because of their biodegradability, biopolymeric nanoparticles (BNPs) have received a lot of attention in the development of new anticancer drug delivery systems. Biopolymer-based nanoparticle systems can be made in a variety of ways. These systems have developed as a cost-effective and environmentally friendly solution to boost treatment efficacy. Effective drug delivery systems with improved availability, increased selectivity, and lower toxicity are needed. Recent research findings and current knowledge on the use of BNPs in the administration of bioactive chemicals in cancer therapy are summarized in this review.

A comprehensive review on bitter gourd (Momordica charantia L.) as a gold mine of functional bioactive components for therapeutic foods

Bitter gourd is a tropical wine grown mainly in India, China and South East Asia. The plant is cultivated mainly for its fruit part which is edible. Bitter gourd is unaccepted widely due to its bitter taste. Nevertheless, the fruit is a source of several key nutrients. The plant, as a whole contains, more than 60 phyto-medicines that are active against more than 30 diseases, including cancer and diabetes. Currently, the incorporation of the bioactive compounds isolated from bitter gourd into functional foods and beverages finds a new horizon. Nanoencapsulation and novel green extraction methods can be employed to improve the yield and quality of extracted compounds and their stability while incorporation into food products. The present review is an attempt to throw light to nutritional aspects, various bioactive compounds present and important nutraceutical properties of the bitter gourd plant in detail.

Graphical Abstract

Microwave- and Ultrasound-Assisted Extraction of Cucurbitane-Type Triterpenoids from Momordica charantia L. Cultivars and Their Antiproliferative Effect on SAS Human Oral Cancer Cells

Cucurbitane-type triterpenoids are a major class of bioactive compounds present in bitter melon. In the present study, six different cultivars of bitter melon were extracted by using microwave- or ultrasound-assisted techniques to identify the prominent method that can extract the majority of cucurbitane-type triterpenoids. A UHPLC–MS/MS (ultra-high-performance liquid chromatography tandem mass spectrometry) system was used for the identification and quantification of ten cucurbitane-type triterpenoids. The results suggest that the use of microwave-assisted extraction on cultivars 4 and 5 produced higher amounts of the selected cucurbitane-type triterpenoids. The interpretation of principal component analysis also identified that cultivar 4 is significantly different from the others in which the compounds 3β,7β,25-trihydroxycucurbita-5,23(E)-dien-19-al and momordicine I were found in higher quantities. Upon further evaluation, it was also identified that these two triterpenoids can act as antiproliferative agents due to their effects on SAS human oral cancer cell lines.

Plant Derived Bioactive Compounds, Their Anti-Cancer Effects and In Silico Approaches as an Alternative Target Treatment Strategy for Breast Cancer: An Updated Overview

Cancer is one of the most common malignant diseases that occur worldwide, among which breast cancer is the second leading cause of death in women. The subtypes are associated with differences in the outcome and were selected for treatments according to the estrogen receptor, progesterone receptor, and human epidermal growth factor receptor. Triple-negative breast cancer, one of the subtypes of breast cancer, is difficult to treat and can even lead to death. If breast cancer is not treated during the initial stages, it may spread to nearby organs, a process called metastasis, through the blood or lymph system. For in vitro studies, MCF-7, MDA-MB-231, MDA-MB-468, and T47B are the most commonly used breast cancer cell lines. Clinically, chemotherapy and radiotherapy are usually expensive and can also cause side effects. To overcome these issues, medicinal plants could be the best alternative for chemotherapeutic drugs with fewer side effects and cost-effectiveness. Furthermore, the genes involved in breast cancer can be regulated and synergized with signaling molecules to suppress the proliferation of breast cancer cells. In addition, nanoparticles encapsulating (nano-encapsulation) medicinal plant extracts showed a significant reduction in the apoptotic and cytotoxic activities of breast cancer cells. This present review mainly speculates an overview of the native medicinal plant derived anti-cancerous compounds with its efficiency, types and pathways involved in breast cancer along with its genes, the mechanism of breast cancer brain metastasis, chemoresistivity and its mechanism, bioinformatics approaches which could be an effective alternative for drug discovery.

TCD, a triterpenoid isolated from wild bitter gourd, reduces synaptosomal release of glutamate and protects against kainic acid-induced neuronal death

3β,7β,25-Trihydroxycucurbita-5,23(E)-dien-19-al (TCD) is a triterpenoid isolated from wild bitter gourd that is a common tropical vegetable with neuroprotective effects. Because excessive glutamate release is a major cause of neuronal damage in various neurological disorders, the aims of this study were to examine the effect of TCD on glutamate release in vitro and to examine the effect of TCD in vivo. In rat cerebrocortical synaptosomes, TCD reduced 4-aminopyridine (4-AP)-stimulated glutamate release and Ca2+ concentration elevation, but had no effect on plasma membrane potential. TCD-mediated inhibition of 4-AP-induced glutamate release was dependent on the presence of extracellular calcium; persisted in the presence of the glutamate transporter inhibitor dl-TBOA, P/Q-type Ca2+ channel blocker ω-agatoxin IVA, and intracellular Ca2+-releasing inhibitors dantrolene and CGP37157; and was blocked by the vesicular transporter inhibitor bafilomycin A1 and the N-type Ca2+ channel blocker ω-conotoxin GVIA. Molecular docking studies have demonstrated that TCD binds to N-type Ca2+ channels. TCD-mediated inhibition of 4-AP-induced glutamate release was abolished by the Ca2+-dependent protein kinase C (PKC) inhibitor Go6976, but was unaffected by the Ca2+-independent PKC inhibitor rottlerin. Furthermore, TCD considerably reduced the phosphorylation of PKC, PKCα, and myristoylated alanine-rich C kinase substrate, a major presynaptic substrate for PKC. In a rat model of kainic acid (KA)-induced excitotoxicity, TCD pretreatment substantially attenuated KA-induced neuronal death in the CA3 hippocampal region. These results suggest that TCD inhibits synaptosomal glutamate release by suppressing N-type Ca2+ channels and PKC activity and exerts protective effects against KA-induced excitotoxicity in vivo.

Thermal treatment enhances the α-glucosidase inhibitory activity of bitter melon (Momordica charantia) by increasing the free form of phenolic compounds and the contents of Maillard reaction products

Inhibition of α-glucosidase can slow carbohydrate metabolism, which is known as an effective strategy for diabetes treatment. The aim of this study is to evaluate the effect of thermal treatment (50, 60, and 70℃) for 15 days on the α-glucosidase inhibitory activity of bitter melon. The results show that the bitter melon heated at 70℃ for 12 days had the best α-glucosidase inhibitory effect. However, the amount of free polyphenols, 5-hydroxymethyl-2-furfural (5-HMF), and the browning degree of bitter melon generally increased with the time (15 days) and temperature of the thermal treatment, which is positively related to their antioxidant and α-glucosidase inhibitory activities. In conclusion, aged bitter melon shows great α-glucosidase inhibitory activity, which may be related to the increased free form of the involved phenolic compounds and Maillard reaction products. This suggests that thermal processing may be a good way to enhance the application of bitter melon for diabetes treatment. PRACTICAL APPLICATION: The thermal processing of bitter melon provides an application for diabetes treatment. This study demonstrated that heat-treated bitter melon can lower the blood glucose level; therefore, it can be used as a potential anti-hyperglycemic and functional food.

A link between chemical structure and biological activity in triterpenoids

BACKGROUND

Plants with triterpenoid compounds in nature have various biological activities and are reported in many scientific works of literature. Triterpenoids are compounds that draw the attention of scientists because of their wide source, wide variety, high medicinal value, and anti-tumor properties. However, a lack of approach to understand their chemical structures has limited the fundamental comprehension of these compounds in cancer cell therapy.

OBJECTIVE

To seek anti-cancer activity of the structures of triterpenoid compounds and their derivatives, we summarized a number of plants and their derivatives that are a source of potential novel therapeutic anti-cancer agents.

METHODS

This work focuses on relevant 1036 patents and references that detail the structure of organic compounds and derivatives for the treatment of tumors.

RESULT

Compared to tetracyclic triterpenoid, pentacyclic triterpenoid has contributed more to improve the autophagic signaling pathways of cancer cells.

CONCLUSION

The heterogenous skeleton structure of triterpenoids impaired the programmed cell death signaling pathway in various cancers.

Suppressive Effect of Two Cucurbitane-Type Triterpenoids from Momordica charantia on Cutibacterium acnes-Induced Inflammatory Responses in Human THP-1 Monocytic Cell and Mouse Models

Cutibacterium acnes (formerly Propionibacterium acnes) is one of the major bacterial species responsible for acne vulgaris. Numerous bioactive compounds from Momordica charantia Linn. var. abbreviata Ser. have been isolated and examined for many years. In this study, we evaluated the suppressive effect of two cucurbitane-type triterpenoids, 5β,19-epoxycucurbita-6,23-dien-3β,19,25-triol (Kuguacin R; KR) and 3β,7β,25-trihydroxycucurbita-5,23-dien-19-al (TCD) on live C. acnes-stimulated in vitro and in vivo inflammatory responses. Using human THP-1 monocytes, KR or TCD suppressed C. acnes-induced production of interleukin (IL)-1β, IL-6 and IL-8 at least above 56% or 45%, as well as gene expression of these three pro-inflammatory cytokines. However, a significantly strong inhibitory effect on production and expression of tumor necrosis factor (TNF)-α was not observed. Both cucurbitanes inhibited C. acnes-induced activation of the myeloid differentiation primary response 88 (MyD88) (up to 62%) and mitogen-activated protein kinases (MAPK) (at least 36%). Furthermore, TCD suppressed the expression of pro-caspase-1 and cleaved caspase-1 (p10). In a separate study, KR or TCD decreased C. acnes-stimulated mouse ear edema by ear thickness (20% or 14%), and reduced IL-1β-expressing leukocytes and neutrophils in mouse ears. We demonstrated that KR and TCD are potential anti-inflammatory agents for modulating C. acnes-induced inflammation in vitro and in vivo.

In silico predictions on the possible mechanism of action of selected bioactive compounds against breast cancer

ABSTRACT

Breast cancer is one of the leading causes of death among women. We employed in silico model to predict the mechanism of actions of selected novel compounds reported against breast cancer using ADMET profiling, drug likeness and molecular docking analyses. The selected compounds were andrographolide (AGP), dipalmitoylphosphatidic acid (DPA), 3-(4-Bromo phenylazo)-2,4-pentanedione (BPP), atorvastatin (ATS), benzylserine (BZS) and 3β,7β,25-trihydroxycucurbita-5,23(E)-dien-19-al (TCD). These compounds largely conform to ADMETlab and Lipinki's rule of drug likeness criteria in addition to their lesser hepatotoxic and mutagenic effects. Docking studies revealed a strong affinity of AGP versus NF-kB (- 6.8 kcal/mol), DPA versus Cutlike-homeobox (- 5.1 kcal/mol), BPP versus Hypoxia inducing factor 1 (- 7.7 kcal/mol), ATS versus Sterol Regulatory Element Binding Protein 2 (- 7.2 kcal/mol), BZS versus Ephrin type-A receptor 2 (- 4.4 kcal/mol) and TCD versus Ying Yang 1 (- 9.4 kcal/mol). Likewise, interaction between the said compounds and respective gene products were evidently observed with strong affinities; AGP versus COX-2 (- 9.6 kcal/mol), DPA versus Fibroblast growth factor receptor (- 5.9 kcal/mol), BPP versus Vascular endothelial growth factor (- 5.8 kcal/mol), ATS versus HMG-COA reductase (- 9.1 kcal/mol), BZS versus L-type amino acid transporter 1 (- 5.3 kcal/mol) and TCD versus Histone deacytylase (- 7.7 kcal/mol), respectively. The compounds might potentially target transcription through inhibition of promoter-transcription factor binding and/or inactivation of final gene product. Thus, findings from this study provide a possible mechanism of action of these xenobiotics to guide in vitro and in vivo studies in breast cancer.

GRAPHIC ABSTRACT

Momordica charantia Suppresses Inflammation and Glycolysis in Lipopolysaccharide-Activated RAW264.7 Macrophages

Macrophage activation is a key event that triggers inflammatory response. The activation is accompanied by metabolic shift such as upregulated glucose metabolism. There are accumulating evidences showing the anti-inflammatory activity of Momordica charantia. However, the effects of M. charantia on inflammatory response and glucose metabolism in activated macrophages have not been fully established. The present study aimed to examine the effect of M. charantia in modulating lipopolysaccharide (LPS)-induced inflammation and perturbed glucose metabolism in RAW264.7 murine macrophages. The results showed that LPS-induced NF-κB (p65) nuclear translocation was inhibited by M. charantia treatment. In addition, M. charantia was found to reduce the expression of inflammatory genes including IL6, TNF-α, IL1β, COX2, iNOS, and IL10 in LPS-treated macrophages. Furthermore, the data showed that M. charantia reduced the expression of GLUT1 and HK2 genes and lactate production (-28%), resulting in suppression of glycolysis. Notably, its effect on GLUT1 gene expression was found to be independent of LPS-induced inflammation. A further experiment also indicated that the bioactivities of M. charantia may be attributed to its key bioactive compound, charantin. Taken together, the study provided supporting evidences showing the potential of M. charantia for the treatment of inflammatory disorders.

Bitter Melon (Momordica Charantia), a Nutraceutical Approach for Cancer Prevention and Therapy

Cancer is the second leading cause of death worldwide. Many dietary plant products show promising anticancer effects. Bitter melon or bitter gourd (Momordica charantia) is a nutrient-rich medicinal plant cultivated in tropical and subtropical regions of many countries. Traditionally, bitter melon is used as a folk medicine and contains many bioactive components including triterpenoids, triterpene glycoside, phenolic acids, flavonoids, lectins, sterols and proteins that show potential anticancer activity without significant side effects. The preventive and therapeutic effects of crude extract or isolated components are studied in cell line-based models and animal models of multiple types of cancer. In the present review, we summarize recent progress in testing the cancer preventive and therapeutic activity of bitter melon with a focus on underlying molecular mechanisms. The crude extract and its components prevent many types of cancers by enhancing reactive oxygen species generation; inhibiting cancer cell cycle, cell signaling, cancer stem cells, glucose and lipid metabolism, invasion, metastasis, hypoxia, and angiogenesis; inducing apoptosis and autophagy cell death, and enhancing the immune defense. Thus, bitter melon may serve as a promising cancer preventive and therapeutic agent.

Targeting Autophagic Pathways by Plant Natural Compounds in Cancer Treatment

Nowadays, natural compounds of plant origin with anticancer effects have gained more attention because of their clinical safety and broad efficacy profiles. Autophagy is a multistep lysosomal degradation pathway that may have a unique potential for clinical benefit in the setting of cancer treatment. To retrieve articles related to the study, the databases of Google Scholar, Web of sciences, Medline and Scopus, using the following keywords: Autophagic pathways; herbal medicine, oncogenic autophagic pathways, tumor-suppressive autophagic pathways, and cancer were searched. Although natural plant compounds such as resveratrol, curcumin, oridonin, gossypol, and paclitaxel have proven anticancer potential via autophagic signaling pathways, there is still a great need to find new natural compounds and investigate the underlying mechanisms, to facilitate their clinical use as potential anticancer agents through autophagic induction.

MicroRNAs and Epigenetics Strategies to Reverse Breast Cancer

Breast cancer is a sporadic disease with genetic and epigenetic components. Genomic instability in breast cancer leads to mutations, copy number variations, and genetic rearrangements, while epigenetic remodeling involves alteration by DNA methylation, histone modification and microRNAs (miRNAs) of gene expression profiles. The accrued scientific findings strongly suggest epigenetic dysregulation in breast cancer pathogenesis though genomic instability is central to breast cancer hallmarks. Being reversible and plastic, epigenetic processes appear more amenable toward therapeutic intervention than the more unidirectional genetic alterations. In this review, we discuss the epigenetic reprogramming associated with breast cancer such as shuffling of DNA methylation, histone acetylation, histone methylation, and miRNAs expression profiles. As part of this, we illustrate how epigenetic instability orchestrates the attainment of cancer hallmarks which stimulate the neoplastic transformation-tumorigenesis-malignancy cascades. As reversibility of epigenetic controls is a promising feature to optimize for devising novel therapeutic approaches, we also focus on the strategies for restoring the epistate that favor improved disease outcome and therapeutic intervention.

Bitter gourd (Momordica charantia) possess developmental toxicity as revealed by screening the seeds and fruit extracts in zebrafish embryos

Background

Bitter gourd (Momordica charantia) has attracted the focus of researchers owing to its excellent anti-diabetic action. The beneficial effect of Momordica charantia on heart has been reported by in vitro and in vivo studies. However the developmental toxicity or potential risk of M. charantia on fetus heart development is largely unknown. Hence this study was designed to find out the developmental toxicity of M. charantia using zebrafish (Danio rerio) embryos.

Methods

The crude extracts were prepared from fruit and seeds of M. charantia. The Zebrafish embryos were exposed to serial dilution of each of the crude extract. The biologically active fractions were fractionated by C18 column using high pressure liquid chromatography. Fourier-transform infrared spectroscopy and gas chromatography coupled with mass spectrophotometry was done to identify chemical constituents in fruit and seed extract of M. charantia.

Results

The seed extract of M. charantia was lethal with LD₅₀ values of 50 μg/ml to zebrafish embryos and multiple anomalies were observed in zebrafish embryos at sub-lethal concentration. However, the fruit extract was much safe and exposing the zebrafish embryos even to 200 μg/ml did not result any lethality. The fruit extract induced severe cardiac hypertrophy in treated embryos. The time window treatment showed that M. charantia perturbed the cardiac myoblast specification process in treated zebrafish embryos. The Fourier-transform infrared spectroscopy analyses revealed diverse chemical group in the active fruit fraction and five new type of compounds were identified in the crude seeds extract of M. charantia by gas chromatography and mass spectrophotometry.

Conclusion

The teratogenicity of seeds extract and cardiac toxicity by the fruit extract of M. charantia warned that the supplementation made from the fruit and seeds of M. charantia should be used with much care in pregnant diabetic patients to avoid possible damage to developing fetus.

Electronic supplementary material

The online version of this article (10.1186/s12906-019-2599-0) contains supplementary material, which is available to authorized users.

Momordica charantia Ethanol Extract Attenuates H₂O₂-Induced Cell Death by Its Antioxidant and Anti-Apoptotic Properties in Human Neuroblastoma SK-N-MC Cells

Oxidative stress, which is induced by reactive oxygen species (ROS), causes cellular damage which contributes to the pathogenesis of neurodegenerative diseases. Momordica charantia (MC), a traditional medicinal plant, is known to have a variety of health benefits, such as antidiabetic, anti-inflammatory, and antioxidant effects. However, it is unknown whether MC has protective effects against oxidative stress-induced neuronal cell death. The aim of this study was to investigate the potential action of MC on oxidative stress induced by H₂O₂. First, we tested whether the pretreatment of Momordica charantia ethanol extract (MCEE) attenuates H₂O₂-induced cell death in human neuroblastoma SK-N-MC cells. MCEE pretreatment significantly improved cell viability and apoptosis that deteriorated by H₂O₂. Further, MCEE ameliorated the imbalance between intracellular ROS production and removal through the enhancement of the intracellular antioxidant system. Intriguingly, the inhibition of apoptosis was followed by the blockage of mitochondria-dependent cell death cascades and suppression of the phosphorylation of the mitogen-activated protein kinase signaling (MAPKs) pathway by MCEE. Taken together, MCEE was shown to be effective in protecting against H₂O₂-induced cell death through its antioxidant and anti-apoptotic properties.

A Sterol from Soft Coral Induces Apoptosis and Autophagy in MCF-7 Breast Cancer Cells

The peroxisome proliferator-activated receptor γ (PPARγ) is a nuclear receptor that plays a key role in regulating cellular metabolism, and is a therapeutic target for cancer therapy. To search for potential PPARγ activators, a compound library comprising 11 marine compounds was examined. Among them, a sterol, 3β,11-dihydroxy-9,11-secogorgost-5-en-9-one (compound 1), showed the highest PPARγ activity with an IC₅₀ value of 8.3 μM for inhibiting human breast adenocarcinoma cell (MCF-7) growth. Western blotting experiments showed that compound 1 induces caspase activation and PARP cleavage. In addition, compound 1 modulated the expression of various PPARγ-regulated downstream biomarkers including cyclin D1, cyclin-dependent kinase (CDK)6, B-cell lymphoma 2 (Bcl-2), p38, and extracellular-signal-regulated kinase (ERK). Moreover, compound 1 increased reactive oxygen species (ROS) generation, upregulated the phosphorylation and expression of H2AX, and induced autophagy. Interestingly, pre-treatment with the autophagy inhibitor 3-methyladenine rescued cells from compound 1-induced growth inhibition, which indicates that the cytotoxic effect of compound 1 is, in part, attributable to its ability to induce autophagy. In conclusion, these findings suggest the translational potential of compound 1 in breast cancer therapy.

Bitter gourd (Momordica charantia) as a rich source of bioactive components to combat cancer naturally: Are we on the right track to fully unlock its potential as inhibitor of deregulated signaling pathways

Research over decades has progressively explored pharmacological actions of bitter gourd (Momordica charantia). Biologically and pharmacologically active molecules isolated from M. charantia have shown significant anti-cancer activity in cancer cell lines and xenografted mice. In this review spotlight was set on the bioactive compounds isolated from M. charantia that effectively inhibited cancer development and progression via regulation of protein network in cancer cells. We summarize most recent high-quality research work in cancer cell lines and xenografted mice related to tumor suppressive role-play of M. charantia and its bioactive compounds. Although M. charantia mediated health promoting, anti-diabetic, hepatoprotective, anti-inflammatory effects have been extensively investigated, there is insufficient information related to regulation of signaling networks by bioactive molecules obtained from M. charantia in different cancers. M. charantia has been shown to modulate AKT/mTOR/p70S6K signaling, p38MAPK-MAPKAPK-2/HSP-27 pathway, cell cycle regulatory proteins and apoptosis-associated proteins in different cancers. However, still there are visible knowledge gaps related to the drug targets in different cancers because we have not yet developed comprehensive understanding of the M. charantia mediated regulation of signal transduction pathways. To explore these questions, experimental platforms are needed that can prove to be helpful in getting a step closer to personalized medicine.

The effects of wild bitter gourd fruit extracts on ICAM-1 expression in pulmonary epithelial cells of C57BL/6J mice and microRNA-221/222 knockout mice: Involvement of the miR-221/-222/PI3K/AKT/NF-κB pathway

BACKGROUND

The extracts from wild bitter gourd fruit (WBGE) were reported to possess numerous pharmacological activities. However, the anti-inflammatory effects of WBGE on human lung epithelial cells and the underlying mechanisms have not been determined.

PURPOSE

To evaluate the molecular basis of the effects of WBGE on intercellular adhesion molecule-1 (ICAM-1) expression in alveolar epithelial (A549) cells, C57BL/6 wild-type (WT) mice and microRNA (miR)-221/-222 knockout (KO) mice with or without tumor necrosis factor (TNF-α; 3 ng/ml) treatment.

STUDY DESIGN/METHODS

WT mice and miR-221/-222 KO mice were fed a control diet and divided into four groups (C: control mice; T: treated with TNF-α alone; WBGE/T: pretreated with WBGE and then stimulated with TNF-α; WBGE: treated with WBGE alone). The effects of WBGE on ICAM-1 expression and the related signals in A549 cells and mice with or without TNF-α treatment were examined by Western blot and immunofluorescent staining.

RESULTS

WBGE significantly decreased the TNF-α-induced ICAM-1 expression in A549 cells through the inhibition of phosphoinositide 3-kinase (PI3K)/ protein kinase B (AKT)/ nuclear factor- kappa B (NF-κB)/ inhibitor of NF-κB (IκB) phosphorylation and decreased leukocyte adhesion. In addition, WBGE reduced endogenous ICAM-1 expression and upregulated miR-221/-222 expression. The overexpression of miR-222 decreased PI3K/AKT/NF-κB/IκB and ICAM-1 expression, which resulted in reducing monocyte adhesion. Moreover, WBGE reduced ICAM-1 expression in lung tissues of WT mice with or without TNF-α treatment and upregulated miR-221/222. WBGE did not affect the miR-221/-222 level and had little effect on ICAM-1 expression in miR-221/-222 KO mice.

CONCLUSIONS

These results suggest that WBGE reduced ICAM-1 expression both under in vitro and in vivo conditions. The protective effects were mediated partly through the miR-221/-222/PI3K/AKT/NF-κB pathway.

Momordica charantia Inhibits Inflammatory Responses in Murine Macrophages via Suppression of TAK1

Momordica charantia known as bitter melon is a representative medicinal plant reported to exhibit numerous pharmacological activities such as antibacterial, antidiabetic, anti-inflammatory, anti-oxidant, antitumor, and hypoglycemic actions. Although this plant has high ethnopharmacological value for treating inflammatory diseases, the molecular mechanisms by which it inhibits the inflammatory response are not fully understood. In this study, we aim to identify the anti-inflammatory mechanism of this plant. To this end, we studied the effects of its methanol extract (Mc-ME) on lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Specifically, we evaluated nitric oxide (NO) production, mRNA expression of inflammatory genes, luciferase reporter gene activity, and putative molecular targets. Mc-ME blocked NO production in a dose-dependent manner in RAW264.7 cells; importantly, no cytotoxicity was observed. Moreover, the mRNA expression levels of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 were decreased by Mc-ME treatment in a dose-dependent manner. Luciferase assays and nuclear lysate immunoblotting analyses strongly indicated that Mc-ME decreases the levels of p65 [a nuclear factor (NF)-[Formula: see text]B subunit] and c-Fos [an activator protein (AP)-1 subunit]. Whole lysate immunoblotting assays, luciferase assays, and overexpression experiments suggested that transforming growth factor [Formula: see text]-activated kinase 1 (TAK1) is targeted by Mc-ME, thereby suppressing NF-[Formula: see text]B and AP-1 activity via downregulation of extracellular signal-regulated kinases (ERKs) and AKT. These results strongly suggest that Mc-ME exerts its anti-inflammatory activity by reducing the action of TAK1, which also affects the activation of NF-[Formula: see text]B and AP-1.

Cyclocommunol induces apoptosis in human oral squamous cell carcinoma partially through a Mcl-1-dependent mechanism

BACKGROUND

Crude extract of breadfruit has been reported to have antitumor activity against various cancer cell lines with unknown mechanism.

PURPOSE

This study aims to investigate the proapoptotic effect of cyclocommunol (CYC), a prenylflavonoid from breadfruit, in two oral squamous cell carcinoma (OSCC) cell lines, SCC2095 and Ca922.

METHODS

The antiproliferative effects of CYC were assessed by MTT assays and PI/annexin V analysis. SCC2095 cells were transiently transfected with Mcl-1 plasmid in overexpression experiment. Other methods used to investigate the mechanism of CYC included Western blotting, acridine orange staining and confocal microscopic visualization.

RESULTS

Our results showed that CYC suppressed the viability of SCC2095 and Ca922 with IC₅₀ values at 48 h of 4.2 and 5.0 µM, respectively. This decrease in viability occurred in a caspase-dependent apoptotic manner. In addition, CYC down-regulated the phosphorylation/expression of Akt/mTOR and Mcl-1, accompanied by reactive oxygen species generation, and autophagy induction. Notably, overexpression of Mcl-1 using Mcl-1-tag-myc partially rescued CYC-mediated caspase-3 activation, PARP cleavage, and cytotoxicity. In summary, our study demonstrated the proapoptotic activity of CYC on OSCC, partially through down-regulation of Mcl-1.

CONCLUSION

CYC from breadfruit has translational value as a proapoptotic agent for OSCC.

Efficiency of novel nanocombinations of bovine milk proteins (lactoperoxidase and lactoferrin) for combating different human cancer cell lines

Bovine lactoperoxidase (LPO) and lactoferrin (LF) are suitable proteins to be loaded or adsorbed to chitosan nanoparticles (NPs) for preparing stable nanoformulations with potent anticancer activity. In the present study, nanocombinations of LPO and LF revealed improvement in their stability and activity compared to single (free or nanoformulated) bovine proteins. The coating or loading of LPO-loaded NPs with LF resulted in the highest synergistic cytotoxicity effect against Caco-2, HepG-2, MCF-7 and PC-3 cells in comparison with other NPs and free proteins without causing toxicity toward normal cells. This synergistic improvement in the anticancer activity was apoptosis-dependent that was confirmed by severe alterations in cellular morphology, high percentage of annexin-stained cells and sub-G1 populations as well as nuclear staining with orange fluorescence of treated cancer cells. Additionally, significant alterations in the expression of well characterized cellular proliferation and apoptosis guards (NF-κB, Bcl-2 and p53) in these NPs-treated cancer cells compared to 5-fluorouracil (5-FU) treated cells. Our findings provide for the first time that these new synergistic nanoformulated forms of LPO and LF were superior in their selective apoptosis-mediating anticancer effect than free form of these proteins and 5-FU. LF coating or loading of LPO-loaded NPs present as promising therapy for cancer.

Identification of a Triterpenoid as a Novel PPARγ Activator Derived from Formosan Plants

Peroxisome proliferator-activated receptor γ (PPARγ), one of the transcription factors that regulate lipid metabolism and energy use in tumor cells, is a viable target for cancer therapy. In our search for potential PPARγ activator, extracts from five Formosan plants were tested. Among them, Momordica charantia L. showed the highest ability to activate PPARγ, which led us to identify its potential constituents. Among the seven compounds isolated from M. charantia, a triterpenoid, 5β,19-epoxy-19-methoxycucurbita-6,23-dien-3β,25-diol (compound 1), was identified as a PPARγ activator with an IC₅₀ of 10 μM in breast cancer MCF-7 cells. Flow cytometric analysis indicated that compound 1 induced G1 cell cycle arrest which might be attributable to the modulation of phosphorylation and expression of numerous key signaling effectors, including cyclin D1, CDK6, and p53. Notably, compound 1 downregulated the expression of histone deacetylase 1, leading to increased histone H3 acetylation. Taken together, these findings suggest that compound 1 may have therapeutic applications in cancer treatment through PPARγ activation. Copyright © 2017 John Wiley & Sons, Ltd.

Bitter Melon Seed Extract does not Alter Photoperiodic Effects on Reproduction of Male Golden Hamsters

Bitter melon (Momordica charantia, MC) has been used in traditional Korean medicine in treating diabetes. In addition, some reports were emerged, showing the antifertility activities of MC in mammals. We investigated the effects of ethanolic MC extract on the reproductive activity of golden hamsters whose spermatogenetic capacity is controlled by their photoperiods. The animals were divided into 4 groups: long photoperiod (LP) control, short photoperiod (SP) control, and LP animals treated with MC. The animals were orally ingested with low (0.03 g/kg) or high (0.15 g/kg) concentrations of the ethanolic extracts for 8 weeks on the daily basis. The control animals received the vehicle. The animals were then mated with age-matched females, experienced pregnancy. As results, the LP control animals showed active large testes but SP control animals displayed remarkably reduced testes. The animals treated with both concentrations of MC extracts demonstrated large testes, indicating fertile activity as animals in LP. LP control animals had litters as expected, but SP controls had no litters at all. MC extract showed the same results as LP animals in generating offsprings. These results suggest that the MC extract does not change the photoperiodic influence on reproductive activity of male golden hamsters.

FTY720 Induces Autophagy-Associated Apoptosis in Human Oral Squamous Carcinoma Cells, in Part, through a Reactive Oxygen Species/Mcl-1-Dependent Mechanism

In this study, we interrogated the mechanism by which the immunosuppressant FTY720 mediates anticancer effects in oral squamous cell carcinoma (OSCC) cells. FTY720 differentially suppressed the viability of the OSCC cell lines SCC4, SCC25, and SCC2095 with IC₅₀ values of 6.1, 6.3, and 4.5 μM, respectively. This antiproliferative effect was attributable to the ability of FTY720 to induce caspase-dependent apoptosis. Mechanistic evidence suggests that FTY720-induced apoptosis was associated with its ability to inhibit Akt-NF-κB signaling, to facilitate the proteasomal degradation of the antiapoptotic protein Mcl-1, and to increase reactive oxygen species (ROS) generation. Both overexpression of Mcl-1 and inhibition of ROS partially protected cells from FTY720-induced caspase-9 activation, PARP cleavage and cytotoxicity. In addition, FTY720 induced autophagy in OSCC cells, as manifested by LC3B-II conversion, decreased p62 expression, and accumulation of autophagosomes. Inhibition of autophagy by bafilomycin A1 protected cells from FTY720-induced apoptosis. Together, these findings suggest an intricate interplay between autophagy and apoptosis in mediating the tumor-suppressive effect in OSCC cells, which underlies the translational potential of FTY720 in fostering new therapeutic strategies for OSCC.

Sutherlandia frutescens modulates adrenal hormone biosynthesis, acts as a selective glucocorticoid receptor agonist (SEGRA) and displays anti-mineralocorticoid properties

ETHNOPHARMACOLOGICAL RELEVANCE

Sutherlandia frutescens is a traditional African medicinal plant used in the treatment of stress and anxiety, while also exhibiting anti-inflammatory properties.

AIM OF STUDY

The study aimed at linking anti-stress and anti-inflammatory properties of S. frutescens to its influence on glucocorticoid biosynthesis and the inflammatory response via steroid receptor interaction.

MATERIALS AND METHODS

The influence of S. frutescens extracts and sutherlandioside B (SUB),10 and 30µM, on key steroidogenic enzymes was assayed in COS-1 cells. Effects were also assayed on basal and stimulated hormone levels in the adrenal H295R cell model. Agonist activity for transactivation and transrepression of the extract and SUB with the glucocorticoid- (GR) and mineralocorticoid receptor (MR) was subsequently investigated.

RESULTS

Inhibitory effects of the extract towards progesterone conversion by CYP17A1 and CYP21A2 were significant. SUB inhibited CYP17A1 and 3β-HSD2, while not affecting CYP21A2. In H295R cells, SUB decreased cortisol and androgen precursors significantly. The extract decreased total steroid production (basal and stimulated) with cortisol and its precursor, deoxycortisol, together with mineralocorticoid metabolites significantly decreased under forskolin stimulated conditions. S. frutescens extracts and SUB repressed NF-κB-driven gene expression without activating GRE-driven gene expression and while neither activated MR mediated gene transcription, both antagonized the effects of aldosterone via the MR.

CONCLUSION

Data provide evidence linking anti-stress, anti-inflammatory and anti-hypertensive properties of S. frutescens to inhibition of steroidogenic enzymes and modulation of adrenal hormone biosynthesis. Findings suggesting S. frutescens and SUB exhibit dissociated glucocorticoid characteristics underline potential therapeutic applications in the treatment of inflammation and hypertension.

T315 Decreases Acute Myeloid Leukemia Cell Viability through a Combination of Apoptosis Induction and Autophagic Cell Death

T315, an integrin-linked kinase (ILK) inhibitor, has been shown to suppress the proliferation of breast cancer, stomach cancer and chronic lymphocytic leukemia cells. Here we demonstrate that T315 decreases cell viability of acute myeloid leukemia (AML) cell lines (HL-60 and THP-1) and primary leukemia cells from AML patients in a dose-responsive manner. Normal human bone marrow cells are less sensitive than leukemia cells to T315. T315 down regulates protein kinase B (Akt) and p-Akt and induces caspase activation, poly-ADP-ribose polymerase (PARP) cleavage, apoptosis and autophagy through an ILK-independent manner. Interestingly, pretreatment with autophagy inhibitors rescues cells from apoptosis and concomitant PARP cleavage, which implicates a key role of autophagic cell death in T315-mediated cytotoxicity. T315 also demonstrates efficacy in vivo, suppressing the growth of THP-1 xenograft tumors in athymic nude mice when administered intraperitoneally. This study shows that autophagic cell death and apoptosis cooperatively contribute to the anticancer activity of T315 in AML cells. In conclusion, the complementary roles of apoptotic and autophagic cell death should be considered in the future assessment of the translational value of T315 in AML therapy.

Pharmacological exploitation of the phenothiazine antipsychotics to develop novel antitumor agents-A drug repurposing strategy

Phenothiazines (PTZs) have been used for the antipsychotic drugs for centuries. However, some of these PTZs have been reported to exhibit antitumor effects by targeting various signaling pathways in vitro and in vivo. Thus, this study was aimed at exploiting trifluoperazine, one of PTZs, to develop potent antitumor agents. This effort culminated in A4 [10-(3-(piperazin-1-yl)propyl)-2-(trifluoromethyl)-10H-phenothiazine] which exhibited multi-fold higher apoptosis-inducing activity than the parent compound in oral cancer cells. Compared to trifluoperazine, A4 demonstrated similar regulation on the phosphorylation or expression of multiple molecular targets including Akt, p38, and ERK. In addition, A4 induced autophagy, as evidenced by increased expression of the autophagy biomarkers LC3B-II and Atg5, and autophagosomes formation. The antitumor activity of A4 also related to production of reactive oxygen species and adenosine monophosphate-activated protein kinase. Importantly, the antitumor utility of A4 was extended in vivo as it, administrated at 10 and 20 mg/kg intraperitoneally, suppressed the growth of Ca922 xenograft tumors. In conclusion, the ability of A4 to target diverse aspects of cancer cell growth suggests its value in oral cancer therapy.