Punicalagin and ellagic acid from pomegranate peel induce apoptosis and inhibits proliferation in human HepG2 hepatoma cells through targeting mitochondria

Pomegranate peel: Bioactivities as antimicrobial and cytotoxic agents

This is a comparative study to evaluate the effectiveness of six pomegranate peel extracts (PPEs) as antibacterial and antiproliferative agents. The Six PPEs were prepared using four solvent systems and each filtrate was concentrated to a gummy material to be used in the evaluation. The well-diffusion method was used to evaluate their antimicrobial activity against bacteria typically associated with food spoilage: Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Listeria monocytogenes, Staphylococcus epidermidis, Staphylococcus aureus, and three Bacillus species. The 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTT) was used to evaluate the cytotoxicity against colorectal carcinoma cells (HCT116), prostate adenocarcinoma (PC3), ovarian cancer cells (SKOV-3), and fibroblasts (MRC-5). The antioxidant evaluation was done using the 2,2-diphenyl-1-picrylhydrazyl-hydrate (DPPH) assay. The pH of the water-containing extracts was acidic and almost the same over 6 weeks. The six PPEs inhibited the bacterial growth in a comparable level to standard antibiotics. The effectiveness of each extract was dependent on the bacterial strain, and the Listeria showed a remarkable inhibition when exposed to the aqueous extract prepared at room temperature (RT). The aqueous (RT) and methanol PPEs had a significant antioxidant scavenging capability and a remarkable cytotoxic activity against the PC3 with half maximal inhibitory concentration (IC50) of 0.1 μg/mL. The boiled aqueous extract exhibited antiproliferative activity against HCT116 with an IC50 of 21.45 μg/mL. The effect on SKOV-3 and fibroblasts was insignificant. With the exception of butanol, the antioxidant screening shows an inverse correlation between the polarity of the extraction solvent and the IC50 exhibited by the PPEs. The variation in the effectiveness of PPEs is suggested to be due to variable soluble bioactive compounds that may interact differently with different cells, though water-containing extracts are promising antibacterial agents. The findings clearly show that pomegranate peel possessed the potential to be an eco-friendly novel source for natural compounds that can be implemented in the food industry as a natural antimicrobial and natural food additive to prevent foodborne illnesses.

Anti-inflammatory effect of a pomegranate extract on LPS-stimulated HepG2 cells

Pomegranate is an important source of bioactive molecules with proven beneficial effects on human health. The aim of this study was to investigate the potential anti-inflammatory effect of a pomegranate extract (PE), obtained from the whole fruit and previously characterized by Reversed Phase-Ultra High-Pressure Liquid Chromatography-High Resolution Mass Spectrometry (RP-UHPLC-HRMS), on HepG2 human hepatocellular carcinoma cells challenged with the lipopolysaccharide (LPS). In LPS-treated cells (1 µg/ml, 24h), the PE treatment (administered at the non-cytotoxic dose of 1 µg/ml, 24h) induced a significant reduction of three key pro-inflammatory cytokines, i.e. interleukin-8 (IL-8), interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α), at both gene expression (as assayed by real-time PCR) and secretion levels (by Enzyme-linked Immunosorbent Assay, ELISA). Although further in vivo studies are needed to prove its efficacy, this preliminary in vitro study suggests that the PE might be useful for ameliorating liver inflammation.

Ellagic acid inhibits tumor growth and potentiates the therapeutic efficacy of sorafenib in hepatocellular carcinoma

Background

Sorafenib is a classic molecular targeted drug approved for hepatocellular carcinoma (HCC) therapy. However, a poor response rate and increasing resistance to sorafenib make its therapeutic efficacy suboptimal. Combination treatment with an agent capable of potentiating sorafenib sensitivity may be a promising solution.

Aim

The aim of this study was to determine the synergistic effect of ellagic acid (EA), a natural polyphenol, and sorafenib on HCC.

Methods

CCK-8, EdU incorporation and colony formation assays were used to study the effect of EA on HCC cell proliferation. Apoptosis was detected by flow cytometry in HCC cells and TUNEL assay in xenograft tumors. Transcriptome analysis was utilized to investigate alterations in signaling pathways with EA treatment. A xenograft mouse model was used to confirm the synergistic effect of sorafenib and EA on HCC tumors in vivo.

Results

We found that EA inhibited growth and induced apoptosis in both HCC cells and xenograft tumors. Mechanistically, EA treatment reduced the activation of the MAPK and Akt/mTOR signaling pathways in HCC cells. Furthermore, combined EA and sorafenib treatment further inhibited the MAPK and Akt/mTOR signaling pathways compared to EA or sorafenib alone. EA synergistically potentiated the anticancer activity of sorafenib against HCC both in vitro and in vivo.

Conclusion

EA inhibits HCC growth by inducing apoptosis through attenuation of the MAPK and Akt/mTOR signaling pathways. EA potentiates the response of HCC tumors to sorafenib both in vitro and in vivo, an effect that may be attributed to further inhibition of the MAPK and Akt/mTOR signaling pathways. These results suggest that EA is an effective adjuvant option for sorafenib therapy.

Ellagic Acid and Cancer Hallmarks: Insights from Experimental Evidence

Cancer is a complex and multifaceted disease with a high global incidence and mortality rate. Although cancer therapy has evolved significantly over the years, numerous challenges persist on the path to effectively combating this multifaceted disease. Natural compounds derived from plants, fungi, or marine organisms have garnered considerable attention as potential therapeutic agents in the field of cancer research. Ellagic acid (EA), a natural polyphenolic compound found in various fruits and nuts, has emerged as a potential cancer prevention and treatment agent. This review summarizes the experimental evidence supporting the role of EA in targeting key hallmarks of cancer, including proliferation, angiogenesis, apoptosis evasion, immune evasion, inflammation, genomic instability, and more. We discuss the molecular mechanisms by which EA modulates signaling pathways and molecular targets involved in these cancer hallmarks, based on in vitro and in vivo studies. The multifaceted actions of EA make it a promising candidate for cancer prevention and therapy. Understanding its impact on cancer biology can pave the way for developing novel strategies to combat this complex disease.

Pomegranate Peel Phytochemistry, Pharmacological Properties, Methods of Extraction, and Its Application: A Comprehensive Review

Pomegranate peel, derived from the processing of Punica granatum L. (pomegranate), has traditionally been considered agricultural waste. However, recent studies have revealed its potential as a rich source of bioactive compounds with diverse pharmacological effects. Pomegranate peel is a rich reservoir of antioxidants, polyphenols, dietary fiber, and vitamins, which contribute to its remarkable bioactivity. Studies have demonstrated the anti-inflammatory, cardioprotective, wound healing, anticancer, and antimicrobial properties of pomegranate peel owing to the presence of phytochemicals, such as gallic acid, ellagic acid, and punicalagin. The extraction of bioactive compounds from pomegranate peel requires a careful selection of techniques to maximize the yield and quality. Green extraction methods, including pressurized liquid extraction (PLE), ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), and enzyme-assisted extraction (EAE), offer efficient and sustainable alternatives to traditional methods. Furthermore, pomegranate peel has been utilized in the food industry, where it can significantly enhance the nutritional value, organoleptic characteristics, and shelf life of food products. Pomegranate peel has the potential to be used to develop innovative functional foods, nutraceuticals, and other value-added products, providing new opportunities for the pharmaceutical, cosmetic, and food industries.

An ellagitannin-loaded CS-PEG decorated PLGA nano-prototype promotes cell cycle arrest in colorectal cancer cells

Colorectal cancer is associated with significant morbidity and mortality worldwide. Egypt, as a developing country, has a high-rise incidence of cancer. The current study objective was to investigate the antitumor influences of ellagitannin-loaded CS-PEG-decorated PLGA nano-prototypes against human colorectal cancer cell lines (HCT 116 as well as Caco-2) in vitro. Doxorubicin (DOX), punicalin (PN), and punicalagin (PNG)-encapsulated chitosan-polyethylene glycol-decorated PLGA (PLGA-CS-PEG) nanoparticles (NPs) were described. The cytotoxicity of each preparation was evaluated using MTT assays in HCT 116 as well as Caco-2 cells during G0, G1, S, and G2 cell cycle phases. Cell cycle-related gene expression and protein levels were measured after treatment. Reactive oxygen species (ROS) levels were also measured. Both PN and PNG PLGA-CS-PEG NPs induce colon cancer cell death with cell cycle arrest in the G1 phase in vitro. Caco-2 cells were more sensitive to the nano-therapy than HCT 116 cells. Upon treatment, the ratio of Bax to Bcl-2 expression was increased following nano-therapy, with increased levels of Cas-3 and decreased expression of Bcl-2, PI3k, and NF-ĸB compared to control. The nitric oxide level (NO), a marker of ROS, was increased following nano-therapy compared to control. In conclusion, ROS-mediated cell cycle arrest can be induced by PN as well as PNG nano-therapy in cell lines of colorectal cancer.

Effects of Pomegranate Peel Polyphenols Combined with Inulin on Gut Microbiota and Serum Metabolites of High-Fat-Induced Obesity Rats

Pomegranate peel polyphenols (PPPs) and inulin have been reported to have lipid-lowering effects. Here, the effects of PPPs combined with inulin on obesity traits and the change of the gut microbiota, short-chain fatty acids (SCFAs), and serum metabolomics profiles in rats with a high-fat diet (HFD) were investigated. According to the experimental results, PPPs were most effective in reducing the body weight and serum and liver lipid levels. Besides, PPPs ameliorated the disorder of gut microbiota, in particular, the enrichment of SCFA producers, such as Lactobacillus, Roseburia, Christensenellaceae_R-7_group, Ruminococcaceae_UCG-005, Bacteroides, and Allobaculum, and the depletion of the Blautia and unclassified Lachnospiraceae population. PPPs also regulated the levels of metabolites changed by HFD feeding via tryptophan metabolism, valine, leucine, and isoleucine biosynthesis, and arachidonic acid metabolism pathways. The correlation analysis showed that PPPs remitted HFD-induced elevation in triglycerides (TGs), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α) levels and lowered high-density lipoprotein (HDL) levels through regulating the gut microbiota, SCFAs, and related metabolites. These findings elucidated that PPPs have a good anti-obesity effect. This study extends the understanding of PPP effects on high-fat-induced obesity, which includes the relationship among gut microbiota, SCFAs, serum metabolites, and TG-, IL-6- and TNF-α- lowering and HDL-elevating functions.

Pomegranate Seeds and Peel Ethanolic Extracts Anticancer Potentials and Related Genetic, Histological, Immunohistochemical, Apoptotic and Oxidative Stress Profiles: In vitro Study

Introduction

Owing to their great quantity of hydrolyzable anthocyanins and tannins, the peel and seeds of pomegranate are edible and possess potent anti-oxidant and anti-inflammatory characteristics. This work aims to trace the pomegranate seed and peel ethanolic extracts' anticancer activity against liver cancer cell line, namely HepG2 and related histopathological, immunohistochemical, genetic and oxidative stress profile.

Methods

In vitro study for both seed and peel extract showed the prevalence of phenols, polyphenols and acids, those have anti-proliferative potential against liver cancer cell line (HepG2) with 50% inhibitory concentration (IC50) of seed significantly reduced that of peel. Toxicity of test extracts was concentration dependent and accompanied with cell cycle arrest and cell death at theG0/G1 and S phases but not at the G2/M phase. Cell arrest was supplemented with raised ROS, MDA and decreased SOD, GSH and Catalase.

Results and discussion

Apoptosis-related genes showed significant up-expression of pro-apoptotic gene (P53), Cy-C, Bax, and casp-3 and down expression of anti-apoptotic gene (Bcl-2). Also, Casp-3 and P53 proteins were substantially expressed under the effect of test extracts. Histopathological study demonstrated that the untreated cells (control group) were regular cells with nuclear pleomorphism and hyperchromatic nuclei, while seed and peel extracts-treated cells showed necrosis, mixed euchromatin and heterochromatin, intra-nuclear eosinophilic structures, burst cell membranes, and the shrunken apoptotic cells with nuclear membranes and irregular cells. Finally, PCNA gene detected by immunohistochemistry was down regulated significantly under the effect of seed extract treatment than in case of cell medication with peel extract.

Punicalagin promotes autophagic degradation of human papillomavirus E6 and E7 proteins in cervical cancer through the ROS-JNK-BCL2 pathway

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This study provides a novel insight into the mechanism of degradation of E6 and E7 caused by punicalagin-induced autophagy. Therefore, our results will offer new strategy for treatment of HPV-infected cervical cancer.

Punicalagin, which is derived from pomegranate peel, is reported to exert growth-inhibitory effects against various cancers. However, the underlying mechanisms have not been elucidated. Human papillomavirus (HPV), a major oncovirus, utilizes the host autophagic machinery to support its replication. Here, punicalagin markedly downregulated the levels of the major HPV oncoproteins E6 and E7 in cervical cancer cells through the autophagy-lysosome system. Additionally, punicalagin activated the reactive oxygen species (ROS)-JNK pathway and promoted the phosphorylation of BCL2, which led to the dissociation of BCL2 from BECN1 and the induction of autophagy. Treatment with autophagy and JNK inhibitors or ROS scavengers mitigated the punicalagin-induced degradation of E6 and E7. Moreover, the knockout of ATG5 using the clustered regularly interspaced palindrome repeat/Cas 9 system mitigated the punicalagin-induced downregulation of E6/E7. This indicated that punicalagin-induced degradation of E6 and E7 was dependent on autophagy. The results of in vivo studies demonstrated that punicalagin efficiently inhibits cervical cancer growth. In conclusion, this study elucidated a mechanism of punicalagin-induced autophagic degradation of E6 and E7. It will enable the future applications of punicalagin as a therapeutic for HPV-induced cervical cancer.

Phenolic Compounds and Bioactivities from Pomegranate (Punica granatum L.) Peels

Pomegranate peels, which are normally processed as the main byproduct of pomegranate juice production, are worthy of being researched and utilized for the aim of economic and environmental benefits. In a phytochemical investigation of the peels of Punica granatum L., 10 phenolic compounds containing a common hexahydroxy diphenol moiety were isolated. Three of them were identified for the first time and named as pomegranatins A-C, and from the other seven known ones, two of them were obtained from pomegranate peels for the first time. Their structures were determined via extensive spectroscopic analysis. Besides, for the sake of preliminarily comprehending their biological activities, in vitro antimicrobial, antioxidant, as well as antitumor assays were detected. In the DPPH antioxidant assay, six compounds presented significant free radical scavenging ability. Two compounds exhibited moderate antimicrobial activities against Candida albicans; one compound could inhibit the proliferation of both C. albicans and Escherichia coli within limits. Four compounds possessed weak antitumor activity toward the Hela cell line without taking into account the bioavailability of ellagitannins. Overall, these results provided further information on the structural diversity of bioactive compounds present in pomegranate peels, as well as on their biological activities.

Recovery from Food Waste-Biscuit Doughs Enriched with Pomegranate Peel Powder as a Model of Fortified Aliment

The aim of the present work is the characterization of biscuit doughs enriched with pomegranate peel powder (PPP) at 3 (PPP3) and 5 (PPP5) wt% in the prospect of developing a fortified aliment as a support of the therapy of chronic inflammatory diseases of the intestinal tract. The total phenolic content of the powder was preliminarily evaluated. Then, the main compounds present in the PPP were identified by HPLC-ESI-TOF-MS analysis, being mainly hydrolysable tannins. The PPP was then treated at 180 °C for 20 min to mimic the baking treatment, and its water-soluble fraction (PPPwsf) was then added in the Caco-2 cell culture as a model of the intestinal epithelial barrier to verify its dose-dependent toxicity, ability in counteracting the oxidative stress, and anti-inflammatory action. Rheological experiments were performed to predict the macroscopic behavior of the PPP-added doughs during lamination and biscuit baking. SEM investigations gave their contribution to the microscopic comprehension of the dough structure. Finally, a consumer panel composed by thirty volunteers was enrolled to express its opinion on the sensory agreeableness of the biscuits prepared with two different concentrations of PPP compared with the reference dough. The discussion is focused on the biological effects of the main components found in the PPP.

The bioactivity and applications of pomegranate peel extract: A review

Pomegranate peel (PP) is a by-product in the processing of pomegranate products, which is usually discarded as a waste. However, a large number of researches have shown that pomegranate peel extract (PPE) is rich in a variety of phenolic substances, among which ellagic acid (EA), as one of the main active components, has significant biological activities, such as anti-oxidation, anti-tumor, anti-inflammatory, neuroprotection, anti-viral, and anti-bacterial. We analyzed the mechanism of EA's biological activity, and discussed its application in the food industry, for instance, food preservation, food additives, and functional foods. Combined with the research status of PPE, we discussed the limitations and development potential of PPE, in order to provide theoretical reference and scientific basis for the development and utilization of pomegranate by-products. PRACTICAL APPLICATIONS: Pomegranate peel (PP), the inedible part of the fruit, is usually treated as waste. In recent years, researchers have been committed to exploring various bioactive ingredients in PP and exploring its potential benefits to human health, which has far-reaching significance. In this paper, the chemical constituents of polyphenols in PP were reviewed, mainly focusing on the biological activity and mechanism of ellagic acid (EA). We reviewed the applications and invention patents of pomegranate peel extract (PPE) in food field, including food preservation, food additive, and functional foods, providing reference for the recycling and reuse of PP.

Ongoing and potential novel trends of pomegranate fruit peel; a comprehensive review of its health benefits and future perspectives as nutraceutical

Pomegranate is an ancient shrub, globally distributed nowadays. It has been used in the middle east as a medicinal food and traditional medicine for thousands of years. Pomegranate peel (PP) constitutes about 50% of the total fruit, however, it has been previously regarded as a waste. Recent research points to PP as a rich source of phenolics (e.g., ellagitannins, flavonoids, and anthocyanins), polysaccharides, in addition to its biotransformed metabolites viz. urolithins making it a valuable waste with promising pharmacological actions. Compared to the pulp and the juice, PP exhibited stronger antioxidant and antimicrobial activities. Besides, it inhibited inflammation in several conditions, including colitis, arthritis, hepatitis, contact dermatitis, and lung inflammation. Moreover, it displayed anti-osteoporosis, anti-hyperglycemic, antidiabetic, antihypertensive, vasculoprotective, hepatoprotective, neuroprotective, and immunomodulatory effects. Additionally, it was effective as a prebiotic and in obesity control, besides it promoted wound healing. Furthermore, PP demonstrated anticancer effects against different cancer types, for example, colon, liver, thyroid, uterine, breast, bladder, prostate, leukemia, and osteosarcoma. Despite PP safety, it may interfere with the metabolism of other drugs because it inhibits cytochromes (CYP) changing their bioavailability, effectiveness, and toxicity. PP biowaste valorization not only avoids against its environmental and economic burden but can also provide a promising platform to produce novel or improved nutraceuticals. This study provides a comprehensive overview of PP biological activities with the reported action mechanisms related to its phytochemicals and further biotransformed metabolites inside the body. Future research prospects to unravel the merits of such waste and optimize its use are discussed. PRACTICAL APPLICATION: Pomegranate is widely distributed throughout the world. Although its peel was previously considered a waste, recent research regards it as a rich source of bioactive compounds with promising biological activities. Its recycling not only overcomes the bio-waste problems, but also provides a source of valuable compounds with several health benefits. In recent years, PP has been demonstrated to exhibit excellent pharmacological bioactivities, for example, antioxidant, anti-inflammatory, antimicrobial, antiosteoporosis, antihyperlipidemic, and anticancer activities. Its health-promoting power is mostly attributed to the phenolic and polysaccharide content, in addition to its amazing biotransformed metabolites. The underlying action mechanisms of such pharmacological activities are discussed and related to its chemical content. This review presents the latest research progress on the role of PP in the prevention and treatment of various chronic diseases, and its protective health effects for future research to be used in nutraceuticals.

Antiproliferative activity of Syzygium coriaceum, an endemic plant of Mauritius, with its UPLC-MS metabolite fingerprint: A mechanistic study

Flowering plants from the Syzygium genus have long been used in different ethnomedicinal systems worldwide and have been under scrutiny for their biological activities. Syzygium coriaceum, an endemic plant of Mauritius has been poorly studied for its potential application against cancer. Herein, Syzygium coriaceum leaf extract has been investigated for its anticancer effect against hepatocellular carcinoma (HepG2) cells. The anticancer activity was assessed using cell proliferation assays, flow cytometry, JC-1 mitochondrial membrane potential assay, and the COMET assay. Un-targeted metabolite profiling via ultra-performance liquid chromatography coupled to high-resolution qTOF-MS (UPLC-MS) and aided by molecular networking was employed to identify the crude extract metabolites. S. coriaceum treatment induced a dose-dependent increase in lactate dehydrogenase leakage into the culture media, peaking up to 47% (p ≤ 0.0001), compared to untreated control. Moreover, at 40 μg/mL, S. coriaceum led to 88.1% (p ≤ 0.0001) drop in mitochondrial membrane potential and 5.7% (p ≤ 0.001) increased in the number of the cell population in G0/G1 phase as well as increased (p < 0.05) the proportion of cells undergoing apoptotic/necrotic cell death. More so, at 10 μg/mL, S. coriaceum induced DNA damage which was 19 folds (p < 0.001) higher than that of untreated control cells. Metabolite profiling indicated the presence of 65 metabolites, out of which 59 were identified. Tannins, flavonoids, nitrogenous compounds, and organic acids were the most predominant classes of compounds detected. Our findings showed that the presence of tannins and flavonoids in S. coriaceum leaf extract could account for the multiple mechanisms of actions underlying the antiproliferative effect against HepG2 cells.

Molecular Action of Polyphenols in Leukaemia and Their Therapeutic Potential

Leukaemia is a malignant disease of the blood. Current treatments for leukaemia are associated with serious side-effects. Plant-derived polyphenols have been identified as potent anti-cancer agents and have been shown to work synergistically with standard chemotherapy agents in leukaemia cell lines. Polyphenols have multiple mechanisms of action and have been reported to decrease cell proliferation, arrest cell cycle and induce apoptosis via the activation of caspase (3, 8 and 9); the loss of mitochondrial membrane potential and the release of cytochrome c. Polyphenols have been shown to suppress activation of transcription factors, including NF-kB and STAT3. Furthermore, polyphenols have pro-oxidant properties, with increasing evidence that polyphenols inhibit the antioxidant activity of glutathione, causing oxidative DNA damage. Polyphenols also induce autophagy-driven cancer cell death and regulate multidrug resistance proteins, and thus may be able to reverse resistance to chemotherapy agents. This review examines the molecular mechanism of action of polyphenols and discusses their potential therapeutic targets. Here, we discuss the pharmacological properties of polyphenols, including their anti-inflammatory, antioxidant, anti-proliferative, and anti-tumour activities, and suggest that polyphenols are potent natural agents that can be useful therapeutically; and discuss why data on bioavailability, toxicity and metabolism are essential to evaluate their clinical use.

Punicalagin Damages the Membrane of Salmonella Typhimurium

Salmonella, a bacterial foodborne pathogen, can contaminate meat, milk, and vegetables. While appropriate measures are available to control Salmonella, the inhibitory phytochemicals from plants are gaining increased attention. Punicalagin, a natural antimicrobial, is one of the main active tannins isolated from Punica granatum L. To obtain a broader understanding of the effect of punicalagin on the cell membranes of Salmonella Typhimurium, the growth curves, extracellular potassium concentration, release of cell constituents, intracellular pH, membrane potential, and morphological features were characterized to elucidate the mechanisms of action. Treatment with punicalagin induced an increase in the extracellular concentrations of potassium and a release of cell constituents. A higher pH gradient, an increase in the intracellular pH, and cell membrane depolarization were observed after punicalagin treatment. Electron microscopy observations showed that the cell membrane structures of Salmonella Typhimurium were damaged by punicalagin. It is concluded that punicalagin inhibits the proliferation of Salmonella Typhimurium and destroys the integrity of the cell membrane, leading to a loss of cell homeostasis. These findings indicate that punicalagin has the potential to be developed as a future alternative to control Salmonella Typhimurium contamination in foods and reduce the risk of salmonellosis.

Terminalia bentzoë, a Mascarene Endemic Plant, Inhibits Human Hepatocellular Carcinoma Cells Growth In Vitro via G0/G1 Phase Cell Cycle Arrest

Tropical forests constitute a prolific sanctuary of unique floral diversity and potential medicinal sources, however, many of them remain unexplored. The scarcity of rigorous scientific data on the surviving Mascarene endemic taxa renders bioprospecting of this untapped resource of utmost importance. Thus, in view of valorizing the native resource, this study has as its objective to investigate the bioactivities of endemic leaf extracts. Herein, seven Mascarene endemic plants leaves were extracted and evaluated for their in vitro antioxidant properties and antiproliferative effects on a panel of cancer cell lines, using methyl thiazolyl diphenyl-tetrazolium bromide (MTT) and clonogenic cell survival assays. Flow cytometry and comet assay were used to investigate the cell cycle and DNA damaging effects, respectively. Bioassay guided-fractionation coupled with liquid chromatography mass spectrometry (MS), gas chromatography-MS, and nuclear magnetic resonance spectroscopic analysis were used to identify the bioactive compounds. Among the seven plants tested, Terminaliabentzoë was comparatively the most potent antioxidant extract, with significantly (p < 0.05) higher cytotoxic activities. T. bentzoë extract further selectively suppressed the growth of human hepatocellular carcinoma cells and significantly halted the cell cycle progression in the G0/G1 phase, decreased the cells' replicative potential and induced significant DNA damage. In total, 10 phenolic compounds, including punicalagin and ellagic acid, were identified and likely contributed to the extract's potent antioxidant and cytotoxic activities. These results established a promising basis for further in-depth investigations into the potential use of T. bentzoë as a supportive therapy in cancer management.

Lagerstroemia speciosa (L.) Pers Leaf Extract Attenuates Lung Tumorigenesis via Alleviating Oxidative Stress, Inflammation and Apoptosis

One of the major etiological factors that account for lung cancer is tobacco use. Benzo(a)pyrene [B(a)P], one of the main constituents of tobacco smoke, has a key role in lung carcinogenesis. The present study was conducted to investigate the cytotoxicity of an aqueous ethanolic extract of Lagerstroemia speciosa (L.) Pers leaves (LLE) on human lung adenocarcinoma cells (A549), as well as its in vivo antitumor effect on a lung tumorigenesis mice model. Our results revealed that LLE possesses cytotoxic activity against the A549 cell line. Mice orally administered B(a)P (50 mg/kg body weight) showed an increase in relative lung weight with subsequent decrease in final body weight. Serum levels of tumor marker enzymes AHH, ADA and LDH and the inflammatory mediator NF-κB increased, while total antioxidant capacity (TAC) decreased. In addition, we observed the increased activity of metalloproteinases (MMP-2 and MMP-12) and levels of the tumor angiogenesis marker VEFG and the lipid peroxidation marker MDA, as well as decreased levels of the non-enzymatic antioxidant GSH and enzymatic antioxidants CAT and GSH-Px in lung tissues. Moreover, B(a)P administration up-regulated the expression of the COX-2 gene, pro-inflammatory cytokines TNF-α and IL-6, and an anti-apoptotic gene Bcl-2, and at the same time down-regulated expression of pro-apoptotic genes BAX and caspase-3 and the p53 gene. Pre- and post-treatment with LLE (250 mg/kg body weight) attenuated all these abnormalities. Histopathological observations verified the protective effect of LLE. Overall, the present data positively confirm the potent antitumor effect of L. speciosa leaves against lung tumorigenesis.