Molecular mechanisms of ampelopsin from Ampelopsis megalophylla induces apoptosis in HeLa cells

Multiple molecular and cellular mechanisms of the antitumour effect of dihydromyricetin (Review)

Dihydromyricetin (DHM) is a natural flavonoid compound with multiple antitumour effects, including inhibition of proliferation, promotion of apoptosis, inhibition of invasion and migration, clearance of reactive oxygen species (ROS) and induction of autophagy. For example, DHM can effectively block the progression of the tumour cell cycle and inhibit cell proliferation. In different types of cancer cells, DHM can regulate the PI3K/Akt pathway, mTOR, and NF-κB pathway components, such as p53, and endoplasmic reticulum stress can alter the accumulation of ROS or induce autophagy to promote the apoptosis of tumour cells. In addition, when DHM is used in combination with various known chemotherapy drugs, such as paclitaxel, nedaplatin, doxorubicin, oxaliplatin and vinblastine, it can increase the sensitivity of tumour cells to DHM and increase the therapeutic effect of chemotherapy drugs. In the present review, the multiple molecular and cellular mechanisms underlying the antitumour effect of DHM, as well as its ability to increase the effects of various traditional antitumour drugs were summarized. Through the present review, it is expected by the authors to draw attention to the potential of DHM as an antitumour drug and provide valuable references for the clinical translation of DHM research and the development of related treatment strategies.

Ampelopsin targets in cellular processes of cancer: Recent trends and advances

Cancer is being considered as a serious threat to human health globally due to limited availability and efficacy of therapeutics. In addition, existing chemotherapeutic drugs possess a diverse range of toxic side effects. Therefore, more research is welcomed to investigate the chemo-preventive action of plant-based metabolites. Ampelopsin (dihydromyricetin) is one among the biologically active plant-based chemicals with promising anti-cancer actions. It modulates the expression of various cellular molecules that are involved in cancer progressions. For instance, ampelopsin enhances the expression of apoptosis inducing proteins. It regulates the expression of angiogenic and metastatic proteins to inhibit tumor growth. Expression of inflammatory markers has also been found to be suppressed by ampelopsin in cancer cells. The present review article describes various anti-tumor cellular targets of ampelopsin at a single podium which will help the researchers to understand mechanistic insight of this phytochemical.

Dihydromyricetin Acts as a Potential Redox Balance Mediator in Cancer Chemoprevention

Dihydromyricetin (DHM) is a flavonoid extracted from the leaves and stems of the edible plant Ampelopsis grossedentata that has been used for Chinese Traditional Medicine. It has attracted considerable attention from consumers due to its beneficial properties including anticancer, antioxidative, and anti-inflammatory activities. Continuous oxidative stress caused by intracellular redox imbalance can lead to chronic inflammation, which is intimately associated with the initiation, promotion, and progression of cancer. DHM is considered a potential redox regulator for chronic disease prevention, and its biological activities are abundantly evaluated by using diverse cell and animal models. However, clinical investigations are still scanty. This review summarizes the current potential chemopreventive effects of DHM, including its properties such as anticancer, antioxidative, and anti-inflammatory activities, and further discusses the underlying molecular mechanisms of DHM in cancer chemoprevention by targeting redox balance and influencing the gut microbiota.

Total flavone extract from Ampelopsis megalophylla induces apoptosis in the MCF‑7 cell line

Ampelopsis megalophylla has been found to demonstrate anticancer activities in human cancer cells; however, the effect of total flavone extract (TFE), commonly used in Traditional Chinese Medicine, remains unclear. Furthermore, there is limited information on its effects on breast cancer cell lines. The present study aimed to investigate the inhibitory effects of TFE in different human cancer cell lines. In addition, the underlying mechanisms and the signaling pathways involved were also investigated by determining tumor cell morphological changes, and differences in the cell cycle, apoptosis, mitochondrial transmembrane potential, and related protein expression levels in a breast cancer cell line. It was found that TFE inhibited proliferation in seven cancer cell lines (HeLa, A549, MCF-7, HepG2, A2780, SW620 and MDA-MB-231 and demonstrated a strong inhibitory effect on MCF-7 cell proliferation. Cell morphological changes were also observed and arrested at the G₂/M phase following treatment with TFE at different concentrations. In addition, TFE disrupted the mitochondrial membrane potential and upregulated the expression level of apoptotic proteins, including caspase-3, -8 and -9, the Bax/Bcl-2 ratio, and Apaf-1 in time-dependent manner. These results indicated that TFE induced apoptosis of the MCF-7 cells via a mitochondrial-mediated apoptotic pathway. In conclusion, TFE is potentially effective in treating breast cancer.

Whole-cell bioconversion of naringenin to high added value hydroxylated compounds using Yarrowia lipolytica 2.2ab in surface and liquid cultures

The bioconversion process of bioactive naringenin by whole-cells of Yarrowia lipolytica 2.2ab for the production of increased value-added compounds is successfully achieved in surface and liquid cultures. This approach is an alternative to the commercial production of these bioactive compounds from vegetable sources, which are limited due to their low concentrations and the complexity of the purification processes. The experimentation rendered seven value-added compounds in both surface and liquid bioconversion cultures. Some of the compounds produced have not been previously reported as products from the bioconversion processes, such as the case of ampelopsin. Biosynthetic pathways were suggested for the naringenin bioconversion using whole-cells of Y. lipolytica 2.2ab. Finally, the extracts obtained from the naringenin bioconversion in liquid cultures showed higher percentage of inhibition of DPPH· and ABTS· radicals up to 32.88 and 2.08 times, respectively, compared to commercial naringenin.

Eriodictyol Inhibits Proliferation, Metastasis and Induces Apoptosis of Glioma Cells via PI3K/Akt/NF-κB Signaling Pathway

Glioma is the most common type of malignant brain tumor. Due to its highly aggressive and metastatic features, glioma is associated with poor prognosis and a lack of effective treatments. Eriodictyol, a natural flavonoid compound, has been reported to possess anti-inflammatory and antioxidant effects. However, the anti-tumor effects of eriodictyol and the underlying mechanisms have rarely been reported. In this study, we found that eriodictyol has anti-tumor activity in lung, colon, breast, pancreas, and liver cancer, and most significantly in glioma cell lines. Eriodictyol dose- and time-dependently suppresses cell proliferation, migration, and invasion in U87MG and CHG-5 glioma cells. In addition, eriodictyol induces apoptosis in U87MG and CHG-5 cells, as evaluated by flow cytometry, immunofluorescence, and Western blot. Furthermore, eriodictyol downregulates the phosphoinositide 3-kinase (PI3K)/Akt/NF-κB signaling pathway in a concentration-dependent manner. Moreover, the effects of eriodictyol on the apoptosis of glioma cells are enhanced by LY294002 (a PI3K inhibitor) and reversed by 740 Y-P (a PI3K agonist). In a mouse xenograft model, eriodictyol not only dramatically suppressed tumor growth but also induced apoptosis in tumor cells. In summary, our data illustrate that eriodictyol effectively inhibits proliferation and metastasis and induces apoptosis of glioma cell lines, which might be a result of the blockade of the PI3K/Akt/NF-κB signaling pathway.

Dietary zerumbone from shampoo ginger: new insights into its antioxidant and anticancer activity

The dietary sesquiterpene dienone zerumbone (ZER) selectively targets cancer cells, inducing mitochondrial dysfunction and apoptosis, and protects non-cancerous cells towards oxidative stress and insult. This study examines the in vitro effects of ZER on lipid peroxidation in biological systems (cholesterol and phospholipid membrane oxidation) and explores its antitumor action in terms of its ability to modulate cancer cell lipid profile. Evaluation of the antioxidant activity of ZER showed that this compound is unable to trap lipoperoxyl radicals per se. ZER significantly modulated the total lipid and fatty acid profiles in cancer cells, inducing marked changes in the phospholipid/cholesterol ratio, with significant decreases in the levels of oleic and palmitic acids and a marked increase of stearic acid. Cell-based fluorescent measurements of intracellular membranes and lipid droplets using the Nile Red staining technique showed that in cancer cells, ZER induced significant accumulation of cytosolic lipid droplets and altered cell membrane organization/protein dynamics, depolarizing the mitochondrial membranes and inducing apoptosis and alteration of nuclear morphology. The modulatory activity of ZER on the total lipid and fatty acid profiles and lipid droplets may therefore represent another possible mechanism of its anticancer properties.

Comparative Transcriptome Analysis of Ampelopsis megalophylla for Identifying Genes Involved in Flavonoid Biosynthesis and Accumulation during Different Seasons

Ampelopsis megalophylla is an important species used in Chinese folk medicine. Flavonoids, the most important active components of plants, greatly determine the quality of A. megalophylla. However, biosynthesis of flavonoids at the molecular and genetic levels in A. megalophylla is not well understood. In this study, we performed chemical analysis and transcriptome analysis of A. megalophylla in different seasons (i.e., May, August, and October). Accumulation of flavonoids was higher in May than in the other two months. Genes involved in the flavonoid biosynthesis pathway, such as chalcone synthase, anthocyanidin synthase, flavanone 3-hydroxylase, flavonoid-3′,5′-hydroxylase, caffeoyl-CoA O-methyltransferase, dihydroflavonol 4-reductase, 4-coumarate-CoA ligase, phenylalanine ammonia-lyase, cinnamate 4-hydroxylase, flavonoid 3′-monooxygenase, shikimate O-hydroxycinnamoyltransferase, and leucoanthocyanidin reductase, were identified based on transcriptome data. Fifty ATP binding cassette (ABC) transporter, nine SNARE, forty-nine GST, and eighty-four glycosyltransferases unigenes related to flavonoid transport and biomodification were also found. Moreover, seventy-eight cytochrome P450s and multiple transcription factors (five MYB, two bHLH, and three WD40 family genes) may be associated with the regulation of the flavonoid biosynthesis process. These results provide insights into the molecular processes of flavonoid biosynthesis in A. megalophylla and offer a significant resource for the application of genetic engineering in developing varieties with improved quality.