Apple flavonoids inhibit growth of HT29 human colon cancer cells and modulate expression of genes involved in the biotransformation of xenobiotics

Phytochemical Profiles, Antioxidant Activity and Antiproliferative Mechanism of Rhodiola rosea L. Phenolic Extract

The phenolic profiles, antioxidant activity, antiproliferative property and the underlying molecular mechanisms of cell apoptosis of Rhodiola rosea free phenolic (RFE) were analyzed in this work. Overall, Rhodiola rosea rhizome phenolic extract (RE) contained Rhodiola rosea rhizome free phenolic extract (RFE) and Rhodiola rosea rhizome bound phenolic extract (RBE). Compared with RBE, RFE contained higher phenolic contents and possessed stronger antioxidant activity. High-performance liquid chromatography (HPLC) results demonstrated that the main phenolics of were epigallocatechin (EGC), epigallocatechin gallate (EGCG), gallic acid (GA) and catechin. Gas chromatography–mass spectrometry (GC-MS) analysis found that Rhodiola rosea L. was rich in volatile phytochemicals. In addition, many types of vitamin E and a few kinds of carotenoids were found in Rhodiola rosea. In addition, the main compounds in RFE (GA, EGC, EGCG) and RFE all exhibited excellent antiproliferative activity, indicating the antiproliferative activity of RFE was partly attributed to the synergy effects of the main compounds. Further study confirmed that RFE could block 16.99% of HepG2 cells at S phase and induce 20.32% programmed cell death compared with the control group. Specifically, RFE dose-dependently induced cell apoptosis and cell cycle arrest via modulating the p53 signaling pathway including up-regulation of the expression of p53 and Bax while down-regulation of the Bcl-2, cyclin D1 and CDK4 levels. Therefore, RFE exhibited the potential of being developed as an auxiliary antioxidant and a therapeutic agent for cancer.

Rutin Promotes Pancreatic Cancer Cell Apoptosis by Upregulating miRNA-877-3p Expression

(1) Background: pancreatic cancer is one of the most serious cancers due to its rapid and inevitable fatality, which has been proved very difficult to treat, compared with many other common cancers. Thus, developing an effective therapeutic strategy, especially searching for potential drugs, is the focus of current research. The exact mechanism of rutin in pancreatic cancer remains unknown. (2) Method: three pancreatic cancer cell lines were used to study the anti-pancreatic cancer effect of rutin. The potent anti-proliferative, anti-migration and pro-apoptotic properties of rutin were uncovered by cell viability, a wound-healing migration assay, and a cell apoptosis assay. High-throughput sequencing technology was used to detect the change of miRNAs expression. Immunoblotting analysis was used to detect the expression of apoptotic proteins. (3) Results: CCK-8 and EDU assays revealed that rutin significantly inhibited pancreatic cancer cells’ proliferation (p < 0.05). A wound-healing assay showed that rutin significantly suppressed pancreatic cancer cells’ migration (p < 0.05). A flow cytometric assay showed that rutin could promote pancreatic cancer cells’ apoptosis. Intriguingly, rutin significantly upregulated miR-877-3p expression to repress the transcription of Bcl-2 and to induce pancreatic cancer cell apoptosis. Accordingly, rutin and miR-877-3p mimics could promote apoptotic protein expression. (4) Conclusions: our findings indicate that rutin plays an important role in anti-pancreatic cancer effects through a rutin-miR-877-3p-Bcl-2 axis and suggests a potential therapeutic strategy for pancreatic cancer.

Metabolomic and Transcriptomic Analyses of the Flavonoid Biosynthetic Pathway for the Accumulation of Anthocyanins and Other Flavonoids in Sweetpotato Root Skin and Leaf Vein Base

Sweetpotato [Ipomoea batatas (L.) Lam.] is a major tuberous root crop that is rich in flavonoids. Here, we discovered a spontaneous mutation in the color of the leaf vein base (LVB) and root skin (RS) in the Zheshu 81 cultivar. The flavonoid and anthocyanin metabolites and molecular mechanism were analyzed using metabolome and transcriptome data. Compared to the wild type, 13 differentially accumulated metabolites (DAMs) in the LVB and 59 DAMs in the RS were all significantly downregulated. Moreover, all the anthocyanin metabolites decreased significantly. The differentially expressed genes (DEGs) encoding the key enzymes in the later enzymatic reaction of anthocyanin and flavonoid were significantly downregulated in the mutant. The expression trends of the transcription factor MYB were evidently related to the anthocyanin content. These results offer insights into the coloration in the LVB and RS and a theoretical basis for determining the regulation of flavonoid and anthocyanin synthesis in sweetpotato.

Proanthocyanidins mitigate bile acid-induced changes in GSTT2 levels in a panel of racially diverse patient-derived primary esophageal cell cultures

Persistent and symptomatic reflux of gastric and duodenal contents, known as gastroesophageal reflux disease (GERD), is the strongest risk factor for esophageal adenocarcinoma (EAC). Despite similar rates of GERD and other risk factors across racial groups, EAC progression disproportionately impacts Caucasians. We recently reported that elevated tissue levels of the detoxification enzyme GSTT2 in the esophagi of Blacks compared to Caucasians may contribute protection. Herein, we extend our research to investigate whether cranberry proanthocyanidins (C-PAC) mitigate bile acid-induced damage and GSTT2 levels utilizing a racially diverse panel of patient-derived primary esophageal cultures. We have shown that C-PACs mitigate reflux-induced DNA damage through GSTT2 upregulation in a rat esophageal reflux model, but whether effects are recapitulated in humans or differentially based on race remains unknown. We isolated normal primary esophageal cells from Black and Caucasian patients and assessed GSTT2 protein levels and cellular viability following exposure to a bile acid cocktail with and without C-PAC treatment. Constitutive GSTT2 levels were significantly elevated in Black (2.9-fold) compared to Caucasian patients, as were GSTT2 levels in Black patients with GERD. C-PAC treatment induced GSTT2 levels 1.6-fold in primary normal esophageal cells. GSTT2 induction by C-PAC was greatest in cells with constitutively low GSTT2 expression. Overall, C-PAC mitigated bile-induced reductions of GSTT2 and subsequent loss of cell viability regardless of basal GSTT2 expression or race. These data support that C-PAC may be a safe efficacious agent to promote epithelial fitness through GSTT2 induction and in turn protect against bile acid-induced esophageal injury.

Screening of anti-cancerous potential of classical Raudra rasa and modified Raudra rasa modified with hiraka bhasma (nanodiamond) through FTIR & LC-MS analysis

OBJECTIVES

Raudra rasa is an ayurvedic medicine explicitly prescribed for the treatment of arbuda (cancer), whereas hiraka bhasma has the potential to promote cancer healing properties. Together, these two medicines provide multifunction benefits. This paper analyses the functional groups of Raudra rasa modified with hiraka bhasma and compares it with the classically prepared raudra rasa. To identify the functional group, organic ligands, and active compounds present in samples of raudra rasa (CRR) and modified raudra rasa with hiraka bhasma (MRR) contributing to cancer alleviation by using Fourier transform infrared spectroscopy (FTIR) & LC-MS analysis.

METHODS

Classical raudra rasa (CRR), its ingredients, shadguna kajjali (SK); decoction of Piper betel Linn. (PBD); Amaranthus spinosus Linn. (ASD); Boerhaavia diffusa Linn. (BDD); Piper longum Linn. (PLD); cow urine (GM), & similarly modified raudra rasa (MRR), its ingredients, hiraka bhasma (HB); shadguna rasasindura (SHR); water-soluble extract of Piper betel Linn. (PBE); Amaranthus spinosus Linn. (ASE); Boerhaavia diffusa Linn. (BDE); cow urine ark (GA); Piper Longum Linn. (PLE) were subjected to FTIR and LC-MS analysis.

RESULTS

Among all 15 samples studied, maximum numbers of peaks (21) were seen in MRR indicating a greater number of functional groups. Further, in MRR, a maximum peak in the double bond region is suggestive of its higher stability compared to CRR. Both the compound is preliminarily a mixture of the number of functional groups like; fluoro, methyl, amino, hydroxy, nitro, methylamino, carbonyl, and iodo groups, having known anti-proliferative activities. By the FT-IR analysis, the biologically active compounds in aqueous and methanol extract of CRR & MRR were identified that have anti-cancerous compounds. In the present study, a total of 40 major compounds like alkaloids, amino acid, carboxylic acid, Flavonoids, Nucleoside, Nucleotide, phenylpropanoid, Sphingosine, stilbenoid, sugar, phosphate, terpenoids, vitamin from aqueous & methanol extract of CRR & MRR were identified by LC-MS.

CONCLUSIONS

This research paper highlights the presence of different functional groups and bioactive compounds known to have anti-cancer activities. Thus, this review suggests future recommendations for the design and development of improved anticancer drugs with higher efficacy.

Onco-Preventive and Chemo-Protective Effects of Apple Bioactive Compounds

Cancer is one of the leading causes of death globally. Epidemiological studies have strongly linked a diet high in fruits to a lower incidence of cancer. Furthermore, extensive research shows that secondary plant metabolites known as phytochemicals, which are commonly found in fruits, have onco-preventive and chemo-protective effects. Apple is a commonly consumed fruit worldwide that is available all year round and is a rich source of phytochemicals. In this review, we summarize the association of apple consumption with cancer incidence based on findings from epidemiological and cohort studies. We further provide a comprehensive review of the main phytochemical patterns observed in apples and their bioavailability after consumption. Finally, we report on the latest findings from in vitro and in vivo studies highlighting some of the key molecular mechanisms targeted by apple phytochemicals in relation to inhibiting multiple 'hallmarks of cancer' that are important in the progression of cancer.

Effects of Alcoholic Extracts of Bangladeshi Mangrove Acanthus ilicifolius Linn. (Acanthaceae) Leaf and Stem on Atherogenic Model of Wistar Albino Rats

Acanthus ilicifolius Linn. (Acanthaceae) is a popular mangrove ethnomedicinal plant that cures several ailments, including asthma, diabetes, cancer, and many others. Our experiment was aimed at evaluating the anti-atherogenic effect of A. ilicifolius (leaf and stem) on a high-fat diet-induced atherogenic rat model. Atherosclerosis was developed in 12 weeks. Treatment with the standard drug (3 mg/kg b.w./day, p.o. of Simvastatin), separate doses of methanolic and ethanolic extracts of A. ilicifolius leaf (250 and 500 mg/kg b.w./day, p.o.), and stem (200 and 400 mg/kg b.w./day, p.o.) was subsequently conducted for additional 15 days. The anti-atherogenic effect was evaluated by estimating the change in body weight, systolic blood pressure, and lipid profile. Histopathology of aorta, liver, and kidney of atherogenic models was done for further evaluation. The antioxidant effect of different extracts was performed via DPPH (2,2-diphenyl-1-picrylhydrazyl) assay using ascorbic acid as standard. The anticoagulant effect was determined after 15 days of treatment with the same doses of the plant extracts and the standard Warfarin (2 mg/kg b.w./day, p.o.). When compared with atherogenic control, treatment with A. ilicifolius significantly reduced (p < 0.01) body weight, systolic blood pressure, and serum lipid levels while it elevated HDL (high-density lipoprotein) level in a dose-dependent manner. Moreover, bleeding and clotting time was significantly decreased (p < 0.01) under the treatment of plant extracts. The histopathological data showed considerable improvement in tissue morphology after treatment. Our study evidenced that the alcoholic extracts of A. ilicifolius leaf and stem have anti-atherogenic properties and may be recommended as a potential herbal remedy for preventing cardiovascular diseases.

Disruption of mitochondrial complexes, cytotoxicity, and apoptosis results from Mancozeb exposure in transformed human colon cells

Ethylene bisdithiocarbamate pesticides, including Mancozeb (MZ), are used as fungicides. Effects of MZ on apoptosis induction and mitochondrial activity of HT-29 colon cells were investigated. MZ exposed cells exhibited blebbing and cellular membrane disruption in scanning electron micrographs. Positive fluorescent staining with Annexin V at doses of 60-140 μM supports apoptosis as the mechanism of cell death. Activity of all electron transport chain complexes were evaluated. Mitochondrial Complex I activity was decreased in 100 μM treated cells. Mitochondrial Complex III activity was decreased in 60 and 100 μM MZ treated cells. Mitochondrial Complex II and Complex IV activities were decreased in cells treated with 60, 100, and 140 μM. Cells treated with 60 μM exhibited a decrease in Complex V enzyme activity. It is concluded that MZ exposure inhibits all mitochondrial complexes of HT-29 cells and that positive fluorescent microscopy and blebbing support previous studies of cell death via apoptosis.

The genetics underlying metabolic signatures in a brown rice diversity panel and their vital role in human nutrition

Brown rice (Oryza sativa) possesses various nutritionally dense bioactive phytochemicals exhibiting a wide range of antioxidant, anti-cancer, and anti-diabetic properties known to promote various human health benefits. However, despite the wide claims made about the importance of brown rice for human nutrition the underlying metabolic diversity has not been systematically explored. Non-targeted metabolite profiling of developing and mature seeds of a diverse genetic panel of 320 rice cultivars allowed quantification of 117 metabolites. The metabolite genome-wide association study (mGWAS) detected genetic variants influencing diverse metabolic targets in developing and mature seeds. We further interlinked genetic variants on chromosome 7 (6.06-6.43 Mb region) with complex epistatic genetic interactions impacting multi-dimensional nutritional targets, including complex carbohydrate starch quality, the glycemic index, antioxidant catechin, and rice grain color. Through this nutrigenomics approach rare gene bank accessions possessing genetic variants in bHLH and IPT5 genes were identified through haplotype enrichment. These variants were associated with a low glycemic index, higher catechin levels, elevated total flavonoid contents, and heightened antioxidant activity in the whole grain with elevated anti-cancer properties being confirmed in cancer cell lines. This multi-disciplinary nutrigenomics approach thus allowed us to discover the genetic basis of human health-conferring diversity in the metabolome of brown rice.

Transcriptional Regulation of Anthocyanin Synthesis by MYB-bHLH-WDR Complexes in Kiwifruit (Actinidia chinensis)

The anthocyanin synthetic pathway is regulated centrally by an MYB-bHLH-WD40 (MBW) complex. Anthocyanin pigmentation is an important fruit quality trait in red-fleshed kiwifruit; however, the underlying regulatory mechanisms involving the MBW complex are not well understood. In this study, one R2R3MYB (AcMYBF110 expressed in fruit characteristically), one bHLH (AcbHLH1), two upstream regulators of AcbHLH1 (AcbHLH4 and AcbHLH5), and one WDR (AcWDR1) are characterized as being involved in the regulation of anthocyanin synthesis in kiwifruit. AcMYBF110 plays an important role in the regulation of anthocyanin accumulation by specifically activating the promoters of several anthocyanin pathway genes including AcCHS, AcF3'H, AcANS, AcUFGT3a, AcUFGT6b, and AcGST1. Coexpression of AcbHLH1, AcbHLH4, or AcbHLH5 together with AcMYBF110 induces much greater anthocyanin accumulation in both tobacco leaves and in Actinidia arguta fruit compared with AcMYBF110 alone. Moreover, this activation is further enhanced by adding AcWDR1. We found that both AcMYBF110 and AcWDR1 interact with all three AcbHLH factors, while AcMYBF110 also interacts with AcWDR1 to form three different MBW complexes that have different regulatory roles in anthocyanin accumulation of kiwifruit. The AcMYBF110-AcbHLH1-AcWDR1 complex directly targets the promoters of anthocyanin synthetic genes. Other features of the regulatory pathways identified include promotion of AcMYBF110, AcbHLH1,and AcWDR1 activities by this MBW complex, providing for both reinforcement and feedback regulation, whereas the AcMYBF110-AcbHLH4/5-AcWDR1 complex is indirectly involved in the regulation of anthocyanin synthesis by activating the promoters of AcbHLH1 and AcWDR1 to amplify the regulation signals of the first MBW complex.

MYB44 competitively inhibits the formation of the MYB340-bHLH2-NAC56 complex to regulate anthocyanin biosynthesis in purple-fleshed sweet potato

BACKGROUND

Anthocyanins, which have important biological functions and have a beneficial effect on human health, notably account for pigmentation in purple-fleshed sweet potato tuberous roots. Individual regulatory factors of anthocyanin biosynthesis have been identified; however, the regulatory network of anthocyanin biosynthesis in purple-fleshed sweet potato is unclear.

RESULTS

We functionally determined that IbMYB340 cotransformed with IbbHLH2 in tobacco and strawberry receptacles induced anthocyanin accumulation, and the addition of IbNAC56a or IbNAC56b caused increased pigmentation. Furthermore, we confirmed the interaction of IbMYB340 with IbbHLH2 and IbNAC56a or IbNAC56b via yeast two-hybrid and firefly luciferase complementation assays; these proteins could form a MYB340-bHLH2-NAC56a or MYB340-bHLH2-NAC56b transcriptional complex to regulate anthocyanin biosynthesis by binding to the IbANS promoter rather than the IbUFGT promoter. Furthermore, it was found by a transient expression system in tobacco leaves that IbMYB44 could decrease anthocyanin accumulation. Moreover, the interaction of IbMYB44 with IbMYB340 and IbNAC56a or IbNAC56b was verified. This result suggested that IbMYB44 acts as a repressor of anthocyanin in sweet potato.

CONCLUSIONS

The repressor IbMYB44 affected anthocyanin biosynthesis by competitively inhibiting the IbMYB340-IbbHLH2-IbNAC56a or IbMYB340-IbbHLH2-IbNAC56b regulatory complex formation. Overall, the present study proposed a novel regulatory network whereby several vital TFs play key roles in regulating anthocyanin biosynthesis, and it provides strong insight into the potential mechanism underlying anthocyanin biosynthesis in sweet potato tuberous roots with purple color.

The Effect of Tartary Buckwheat Flavonoids in Inhibiting the Proliferation of MGC80-3 Cells during Seed Germination

Tartary buckwheat (Fagopyrum tataricum (L.) Gaertn) is rich in functional compounds such as rutin, quercetin, d-chiro-inositol, dietary fiber, and essential amino acids. Electric field (EF) treatment before sprout germination results in physiological and chemical changes, and some alterations might lead to positive applications in plant seeds. MTT assay showed that the effect of total flavonoids on human gastric cancer cell line MGC80-3 was significantly changed after EF treatment for different germination days (3-7 days). Among them, the total flavonoids of tartary buckwheat (BWTF) on the third day had the most obvious inhibitory effect on MGC80-3 (p < 0.01). In addition, flow cytometry evidenced that different ratios of quercetin and rutin had effects on the proliferation of MGC80-3. The same content of quercetin and rutin had the best effect, reaching 6.18 ± 0.82%. The anti-cancer mechanism was mainly promoted by promoting the expression of apoptotic proteins. The expression of Bax/Bcl-2 and caspase-8 in MGC80-3 cells was mediated by BWTFs. This study has good research value for improving the biological and economic value of tartary buckwheat.

Molecular cloning and functional characterization of AcGST1, an anthocyanin-related glutathione S-transferase gene in kiwifruit (Actinidia chinensis)

AcGST1, an anthocyanin-related GST, may functions as a carrier to transport anthocyanins from ER to tonoplast in kiwifruit. It was positively regulated by AcMYBF110 through directly binding to its promoter. Anthocyanins are synthesized in the cytoplasmic surface of the endoplasmic reticulum but accumulate predominantly in the vacuole. Previous studies in model and ornamental plants have suggested that a member of the glutathione S-transferase (GST) gene family is involved in sequestration of anthocyanins into the vacuole. However, little is known about anthocyanin-related GST protein in kiwifruit. Here, four putative AcGSTs were identified from the genome of the red-fleshed Actinidia chinensis cv 'Hongyang'. Expression analyses reveal only the expression of AcGST1 was highly consistent with anthocyanin accumulation. Molecular complementation of Arabidopsis tt19 demonstrates AcGST1 can complement the anthocyanin-less phenotype of tt19. Transient expression in Actinidia arguta fruits further confirms that AcGST1 is functional in anthocyanin accumulation in kiwifruit. In vitro assays show the recombinant AcGST1 increases the water solubility of cyanidin-3-O-galactoside (C3Gal) and cyanidin-3-O-xylo-galactoside (C3XG). We further show that AcGST1 protein is localized not only in the ER but also on the tonoplast, indicating AcGST1 (like AtTT19) may functions as a carrier protein to transport anthocyanins to the tonoplast in kiwifruit. Moreover, the promoter of AcGST1 can be activated by AcMYBF110, based on results from transient dual-luciferase assays and yeast one-hybrid assays. EMSAs show that AcMYBF110 binds directly to CAGTTG and CCGTTG motifs in the AcGST1 promoter. These results indicate that AcMYBF110 plays an important role in transcriptional regulation of AcGST1 and, therefore, in controlling accumulation of anthocyanins in kiwifruit.

Transcriptomic Analysis of Red-Fleshed Apples Reveals the Novel Role of MdWRKY11 in Flavonoid and Anthocyanin Biosynthesis

In plants, flavonoids are important secondary metabolites that contribute to the nutritional quality of many foods. Apple is a popular and frequently consumed food because of its high flavonoid content. In this study, flavonoid composition and content were detected and compared between red- and white-fleshed apples in a BC₁ hybrid population using ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry. Transcriptomic analysis of the red- and white-fleshed apples was then performed using RNA-seq technology. By screening differentially expressed genes encoding transcription factors, we unearthed a WRKY-family transcription factor designated MdWRKY11. Overexpression of MdWRKY11 promoted the expression of F3H, FLS, DFR, ANS, and UFGT and increased the accumulation of flavonoids and anthocyanin in apple calli. Our findings explored the novel role of MdWRKY11 in flavonoid biosynthesis and suggest several other genes that may also be potentially involved. This provides valuable information on flavonoid synthesis for the breeding of elite red-fleshed apples.

The blue light signal transduction pathway is involved in anthocyanin accumulation in 'Red Zaosu' pear

MAIN CONCLUSION

A conserved blue light sensing and transduction pathway contributes to blue light-induced anthocyanin accumulation in the peel of red pear. Peel color is an economically important characteristic that influences the appearance quality of red pear, whose red color is due to anthocyanin accumulation. The process of coloration in the fruit peel is strongly influenced by light. However, how light quality influences color development remains unclear. In this study, we analyzed the effects of different light qualities on color development in the red pear 'Red Zaosu', a mutant of the hybrid cultivar 'Zaosu' of Pyrus pyrifolia and P. communis. The results showed that blue light increased anthocyanin accumulation after 72 h of light treatment, while red light had almost no effect. The expression of anthocyanin biosynthesis-related genes showed a similar trend to the anthocyanin accumulation. To clarify the mechanism of blue-light induced coloration, PpCRYs, PpCOP1 and PpHY5 genes were cloned. Gene expression analysis showed that their transcript abundance did not correlate with the expression of anthocyanin-related genes or anthocyanin content, but the yeast two-hybrid system revealed conserved physical interactions among these proteins. In addition, PpHY5 directly bound to the promoters of the anthocyanin biosynthesis genes PpCHS, PpDFR, PpANS and PpMYB10, and activated the transcription of PpCHS in a Nicotiana benthamiana-based dual-luciferase assay. In summary, our results preliminarily revealed that the conserved blue light signal transduction module CRY-COP1-HY5 contributed to the anthocyanin biosynthesis induced by blue light in red pear. However, our results did not provide evidence for why red light had no effect on anthocyanin accumulation, which needs further study.

Chlorogenic Acid and Its Microbial Metabolites Exert Anti-Proliferative Effects, S-Phase Cell-Cycle Arrest and Apoptosis in Human Colon Cancer Caco-2 Cells

Chlorogenic acid (CGA) decreases colon cancer-cell proliferation but the combined anti-cancer effects of CGA with its major colonic microbial metabolites, caffeic acid (CA), 3-phenylpropionic acid (3-PPA) and benzoic acid (BA), needs elucidation as they occur together in colonic digesta. Caco-2 cancer cells were treated for 24 h with the four compounds individually (50–1000 µM) and as an equimolar ratio (1:1:1:1; MIX). The effective concentration to decrease cell proliferation by 50% (EC₅₀) was lower for MIX (431 ± 51.84 µM) and CA (460 ± 21.88) versus CGA (758 ± 19.09 µM). The EC₅₀ for cytotoxicity measured by lactate dehydrogenase release in MIX (527 ± 75.34 µM) showed more potency than CA (740 ± 38.68 µM). Cell proliferation was decreased by 3-PPA and BA at 1000 µM with no cytotoxicity. Cell-cycle arrest was induced at the S-phase by CA (100 µM), MIX (100 µM), CGA (250 µM) and 3-PPA (500 µM) with activation of caspase-3 by CGA, CA, MIX (500 and 1000 µM). Mitochondrial DNA content was reduced by 3-PPA (1000 µM). The anti-cancer effects occurred at markedly lower concentrations of each compound within MIX than when provided singly, indicating that they function together to enhance anti-colon cancer activities.

Polyphenols in Colorectal Cancer: Current State of Knowledge including Clinical Trials and Molecular Mechanism of Action

Polyphenols have been reported to have wide spectrum of biological activities including major impact on initiation, promotion, and progression of cancer by modulating different signalling pathways. Colorectal cancer is the second most major cause of mortality and morbidity among females and the third among males. The objective of this review is to describe the activity of a variety of polyphenols in colorectal cancer in clinical trials, preclinical studies, and primary research. The molecular mechanisms of major polyphenols related to their beneficial effects on colorectal cancer are also addressed. Synthetic modifications and other future directions towards exploiting of natural polyphenols against colorectal cancer are discussed in the last section.

Map-based cloning of the pear gene MYB114 identifies an interaction with other transcription factors to coordinately regulate fruit anthocyanin biosynthesis

Red fruits are popular and widely accepted by consumers because of an enhanced appearance and enriched anthocyanins. The molecular mechanism of anthocyanin regulation in red-skinned pear (Pyrus) has been studied, and the genes encoding the biosynthetic steps and several transcription factors (TFs) have been characterized. In this study, a candidate R2R3 MYB TF, PyMYB114, was identified by linkage to the quantitative trait loci (QTL) for red skin color on linkage group 5 in a population of Chinese pear (Pyrus bretschneideri). The function of PyMYB114 was verified by transient transformation in tobacco (Nicotinana tabacum) leaves and strawberry (Fragaria) and pear fruits, resulting in the biosynthesis of anthocyanin. Suppression of PyMYB114 could inhibit anthocyanin biosynthesis in red-skinned pears. The ERF/AP2 TF PyERF3 was found to interact with PyMYB114 and its partner PybHLH3 to co-regulate anthocyanin biosynthesis, as shown by a dual luciferase reporter system and a yeast two-hybrid assay. In addition, the transcript abundance of PyMYB114 and PyMYB10 were correlated, and co-transformation of these two genes into tobacco and strawberry led to enhanced anthocyanin biosynthesis. This interaction network provides insight into the coloration of fruits and the interaction of different TFs to regulate anthocyanin biosynthesis.

Potent nematicidal activity of phenolic derivatives on Meloidogyne incognita

The present study describes the nematicidal activity of ten selected phenolic derivatives using the root knot nematode, Meloidogyne incognita, model. Nematicidal activity was then correlated with the anti-oxidant power. The highest nematicidal activity was recorded for p-nitrophenol followed by m-nitrophenol, o-nitrophenol and p-bromophenol, with an EC50 after 1 day of immersion of about 0.70 ± 0.64, 8.14 ± 5.49, 15.79 ± 10.81 and 25.92 ± 11.37 μg/ml, respectively. The structure-activity relationship indicates that the nitro-group at position 4 on the phenolic ring (p-nitrophenol) is very important for nematicidal activity, followed by that at position 2 (o-nitrophenol) and position 3 (m-nitrophenol). p-Nitrophenol showed the highest nematicidal activity with the corresponding lowest anti-oxidant activity of about 97 ± 20 μg/ml. In conclusion, these findings suggest that phenolic derivatives could be considered as potent nematicidal agents and be integrated in the pest-management system.

Optimization of the ultrasound-assisted extraction of antioxidant phloridzin from Lithocarpus polystachyus Rehd. using response surface methodology

The purpose of this study was to optimize the extraction process of phloridzin from Lithocarpus polystachyus Rehd. leaves using response surface methodology and to determine the antioxidant capacity of the extract. A Box-Behnken design was used to analyze the effects of ethanol concentration, liquid-solid ratio, soak time and extraction time on the extraction yield of phloridzin. The content of phloridzin was determined by high-performance liquid chromatography. To assess the antioxidant capacity of the extract, three in vitro test systems were used (1,1-,diphenyl-2-picrylhydrazyl, hydroxyl radical scavenging test and reduction force). The optimal parameters obtained by response surface methodology were a volume fraction of ethanol of 64%, a liquid-solid ratio of 37:1, a soaking time of 35 h and a sonication time of 38 min. The proportion of the extraction of phloridzin from L. polystachyus under these industrial process conditions was 3.83%. According to the obtained results, response surface methodology could be suggested as an adequate model for optimizing the extraction process of phloridzin from L. polystachyus. Ultrasound extraction significantly increased the extraction rate of phloridzin, which could be used as an antioxidant in pharmaceutical and food products.

The role of Nrf2-Keap1 axis in colorectal cancer, progression, and chemoresistance

Colorectal cancer is the third common cancer after lung and genital cancers worldwide with more than 1.2 million new cases diagnosed annually. Although extensive progress has been made in the treatment of colorectal cancer, finding novel targets for early diagnosis and effective treatment of these patients is an urgent need. Nuclear factor-erythroid 2-kelch-like ECH-associated protein 1 signaling pathway plays a key role in protecting cells from the damage of intracellular oxidative stress and extracellular oxidizing agents. Nuclear factor-erythroid 2 is a transcription factor that creates intracellular redox homeostasis via transcriptional activity and interaction with kelch-like ECH-associated protein 1. Furthermore, it contributes to survival and chemoresistance of colorectal cancer cells which is mediated by overexpression of cytoprotective and multidrug resistance genes. In this review, the dual role of nuclear factor-erythroid 2 signaling in induction of colorectal cancer cell survival and death as well as the possibility of targeting nuclear factor-erythroid 2-kelch-like ECH-associated protein 1 axis as an advanced strategy in prevention and effective treatment of colorectal cancer patients have been discussed.

Antibacterial, Anticancer and Neuroprotective Activities of Rare Actinobacteria from Mangrove Forest Soils

Mangrove is a complex ecosystem that contains diverse microbial communities, including rare actinobacteria with great potential to produce bioactive compounds. To date, bioactive compounds extracted from mangrove rare actinobacteria have demonstrated diverse biological activities. The discovery of three novel rare actinobacteria by polyphasic approach, namely Microbacterium mangrovi MUSC 115T, Sinomonas humi MUSC 117T and Monashia flava MUSC 78T from mangrove soils at Tanjung Lumpur, Peninsular Malaysia have led to the screening on antibacterial, anticancer and neuroprotective activities. A total of ten different panels of bacteria such as Methicillin-resistant Staphylococcus aureus (MRSA) ATCC 43300, ATCC 70069, Pseudomonas aeruginosa NRBC 112582 and others were selected for antibacterial screening. Three different neuroprotective models (hypoxia, oxidative stress, dementia) were done using SHSY5Y neuronal cells while two human cancer cells lines, namely human colon cancer cell lines (HT-29) and human cervical carcinoma cell lines (Ca Ski) were utilized for anticancer activity. The result revealed that all extracts exhibited bacteriostatic effects on the bacteria tested. On the other hand, the neuroprotective studies demonstrated M. mangrovi MUSC 115T extract exhibited significant neuroprotective properties in oxidative stress and dementia model while the extract of strain M. flava MUSC 78T was able to protect the SHSY5Y neuronal cells in hypoxia model. Furthermore, the extracts of M. mangrovi MUSC 115T and M. flava MUSC 78T exhibited anticancer effect against Ca Ski cell line. The chemical analysis of the extracts through GC-MS revealed that the majority of the compounds present in all extracts are heterocyclic organic compound that could explain for the observed bioactivities. Therefore, the results obtained in this study suggested that rare actinobacteria discovered from mangrove environment could be potential sources of antibacterial, anticancer and neuroprotective agents.

Protective Role of Dietary Berries in Cancer

Dietary patterns, including regular consumption of particular foods such as berries as well as bioactive compounds, may confer specific molecular and cellular protection in addition to the overall epidemiologically observed benefits of plant food consumption (lower rates of obesity and chronic disease risk), further enhancing health. Mounting evidence reports a variety of health benefits of berry fruits that are usually attributed to their non-nutritive bioactive compounds, mainly phenolic substances such as flavonoids or anthocyanins. Although it is still unclear which particular constituents are responsible for the extended health benefits, it appears that whole berry consumption generally confers some anti-oxidant and anti-inflammatory protection to humans and animals. With regards to cancer, studies have reported beneficial effects of berries or their constituents including attenuation of inflammation, inhibition of angiogenesis, protection from DNA damage, as well as effects on apoptosis or proliferation rates of malignant cells. Berries extend effects on the proliferation rates of both premalignant and malignant cells. Their effect on premalignant cells is important for their ability to cause premalignant lesions to regress both in animals and in humans. The present review focuses primarily on in vivo and human dietary studies of various berry fruits and discusses whether regular dietary intake of berries can prevent cancer initiation and delay progression in humans or ameliorate patients’ cancer status.

Quercetin-induced apoptosis of HT-29 colon cancer cells via inhibition of the Akt-CSN6-Myc signaling axis

Constitutive photomorphogenesis 9 signalosome (CSN) consists of a total of eight subunits (CSN1-CSN8) in mammalian cells. CSN6 may promote carcinogenesis by positively regulating v-myc avian myelocytomatosis viral oncogene homolog (Myc) and MDM2 proto-oncogene stability, and is regarded as a potential target for cancer therapy. Quercetin has a substantial anticancer effect on various human cancer cells. The present study investigated the effects of quercetin on HT-29 human colorectal cancer cell viability, apoptosis and cell cycle arrest using an MTT assay, flow cytometry, transmission electron microscopy and western blotting. It was determined that quercetin inhibited HT-29 cell viability in a dose-dependent manner. Cell shrinkage, chromatin condensation and nuclear collapse were observed in the 50, 100 and 200 µM quercetin groups. The exposure of HT-29 cells to quercetin led to significant cell cycle arrest in the S-phase. Western blot analysis revealed that quercetin reduced the protein expression levels of phosphorylated-Akt and increased CSN6 protein degradation; therefore, affecting the expression levels of Myc, p53, B-cell lymphoma 2 (Bcl-2) and Bcl-2 associated X protein. The overexpression of CSN6 reduced the effect of quercetin treatment on HT-29 cells, suggesting that quercetin-induced apoptosis may involve the Akt-CSN6-Myc signaling axis in HT-29 cells.

The preventive and therapeutic potential of natural polyphenols on influenza

Influenza virus belongs to orthomyxoviridae family. This virus is a major public health problems, with high rates of morbidity and mortality. Despite a wide range of pharmacotherapeutic choices inhibiting specific sequences of pathological process of influenza, developing more effective therapeutic options is an immediate challenge. In this paper, a comprehensively review of natural polyphenolic products used worldwide for the management of influenza infection is presented. Cellular and molecular mechanisms of the natural polyphenols on influenza infection including suppressing virus replication cycle, viral hemagglutination, viral adhesion and penetration into the host cells, also intracellular transductional signaling pathways have been discussed in detail. Based on cellular, animal, and human evidence obtained from several studies, the current paper demonstrates that natural polyphenolic compounds possess potential effects on both prevention and treatment of influenza, which can be used as adjuvant therapy with conventional chemical drugs for the management of influenza and its complications.

Transcriptome profiling reveals differential gene expression in proanthocyanidin biosynthesis associated with red/green skin color mutant of pear (Pyrus communis L.)

Anthocyanin concentration is the key determinant for red skin color in pear fruit. However, the molecular basis for development of red skin is complicated and has not been well-understood thus far. "Starkrimson" (Pyrus communis L.), an introduced red pear cultivated in the north of China and its green mutant provides a desirable red/green pair for identification of candidate genes involved in color variation. Here, we sequenced and annotated the transcriptome for the red/green color mutant at three stages of development using Illumina RNA-seq technology. The total number of mapped reads ranged from 26 to 46 million in six libraries. About 70.11-71.95% of clean reads could be mapped to the reference genome. Compared with green colored fruit, a total of 2230 differentially expressed genes (DEGs) were identified in red fruit. Gene Ontology (GO) terms were defined for 4886 differential transcripts involved in 15 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Three DEGs were identified as candidate genes in the flavonoid pathway, LAR, ANR, and C3H. Tellingly, higher expression was found for genes encoding ANR and LAR in the green color mutant, promoting the proanthocyanidin (PA) pathway and leading to lower anthocyanin. MYB-binding cis-motifs were identified in the promoter region of LAR and ANR. Based on these findings, we speculate that the regulation of PA biosynthesis might be a key factor for this red/green color mutant. Besides the known MYB and MADS transcription families, two new families, AP2 and WRKY, were identified as having high correlation with anthocyanin biosynthesis in red skinned pear. In addition, qRT-PCR was used to confirm the transcriptome results for 17 DEGs, high correlation of gene expression, further proved that AP2 and WARK regulated the anthocyanin biosynthesis in red skinned "Starkrimson," and ANR and LAR promote PA biosynthesis and contribute to the green skinned variant. This study can serve as a valuable new resource laying a solid foundation for functional gene identification in the anthocyanin pathway of red-skinned pear and provide a good reference for relevant research on molecular mechanisms of color variation in other pear species.

Inhibition of Breast Cancer Cell Proliferation and In Vitro Tumorigenesis by a New Red Apple Cultivar

PURPOSE

The aim of this study was to evaluate the antiproliferative activity in breast cancer cells and the inhibition of tumorigenesis in pre-neoplastic cells of a new apple cultivar with reddish pulp, called the Pelingo apple.

METHODS

The antiproliferative activity was evaluated in MCF-7 and MDA-MB-231 human breast cancer cells. The inhibition of tumorigenesis was performed in JB6 promotion-sensitive (P+) cells.

RESULTS

Results showed that Pelingo apple juice is characterized by a very high polyphenol content and strongly inhibited breast cancer cell proliferation. Its antiproliferative activity was found to be higher than the other five apple juices tested. Pelingo juice induced cell accumulation in the G2/M phase of the cell cycle and autophagy through overexpression of p21, inhibition of extracellular signal-regulated kinases 1/2 (ERK1/2) activity and an increase in lipidated microtubule-associated protein-1 light chain-3 beta (LC3B). Remarkably, Pelingo juice inhibited the 12-o-tetra-decanoyl-phorbol-13-acetate (TPA)-induced tumorigenesis of JB6 P+ cells, suppressing colony formation in semi-solid medium and TPA-induced ERK1/2 phosphorylation.

CONCLUSIONS

Our data indicate that the Pelingo apple is rich in food components that can markedly inhibit in vitro tumorigenesis and growth of human breast cancer cells and could provide natural bioactive non-nutrient compounds, with potential chemopreventive activity.

Role of the Aryl Hydrocarbon Receptor in Colon Neoplasia

For both men and women, colorectal cancer (CRC) is the second leading cause of cancer death in the United States, primarily as a consequence of limited therapies for metastatic disease. The aryl hydrocarbon receptor (AhR) is a ligand-dependent transcription factor with diverse functions in detoxification of xenobiotics, inflammatory responses, and tissue homeostasis. Emerging evidence indicates that AhR also plays an important role in regulating intestinal cell proliferation and tumorigenesis. Here, we review both the pro- and anti-carcinogenic properties of AhR signaling and its potential role as a therapeutic target in CRC.

RNA sequencing supports distinct reactive oxygen species-mediated pathways of apoptosis by high and low size mass fractions of Bay leaf (Lauris nobilis) in HT-29 cells

Anti-proliferative and pro-apoptotic effects of Bay leaf (Laurus nobilis) in mammalian cancer and HT-29 adenocarcinoma cells have been previously attributed to effects of polyphenolic and essential oil chemical species. Recently, we demonstrated differentiated growth-regulating effects of high (HFBL) versus low molecular mass (LFBL) aqueous fractions of bay leaf and now confirm by comparative effects on gene expression, that HFBL and LFBL suppress HT-29 growth by distinct mechanisms. Induction of intra-cellular lesions including DNA strand breakage by extra-cellular HFBL, invoked the hypothesis that iron-mediated reactive oxygen species with capacity to penetrate cell membrane, were responsible for HFBL-mediated effects, supported by equivalent effects of HFBL in combination with γ radiation. Activities of HFBL and LFBL were interpreted to reflect differentiated responses to iron-mediated reactive oxygen species (ROS), occurring either outside or inside cells. In the presence of LFBL, apoptotic death was relatively delayed compared with HFBL. ROS production by LFBL mediated p53-dependent apoptosis and recovery was suppressed by promoting G1/S phase arrest and failure of cellular tight junctions. In comparison, intra-cellular anti-oxidant protection exerted by LFBL was absent for extra-cellular HFBL (likely polysaccharide-rich), which potentiated more rapid apoptosis by producing DNA double strand breaks. Differentiated effects on expression of genes regulating ROS defense and chromatic condensation by LFBL versus HFBL, were observed. The results support ferrous iron in cell culture systems and potentially in vivo, can invoke different extra-cellular versus intra-cellular ROS-mediated chemistries, that may be regulated by exogenous, including dietary species.

Chemopreventive effect of apple and berry fruits against colon cancer

Colon cancer arises due to the conversion of precancerous polyps (benign) found in the inner lining of the colon. Prevention is better than cure, and this is very true with respect to colon cancer. Various epidemiologic studies have linked colorectal cancer with food intake. Apple and berry juices are widely consumed among various ethnicities because of their nutritious values. In this review article, chemopreventive effects of these fruit juices against colon cancer are discussed. Studies dealing with bioavailability, in vitro and in vivo effects of apple and berry juices are emphasized in this article. A thorough literature survey indicated that various phenolic phytochemicals present in these fruit juices have the innate potential to inhibit colon cancer cell lines. This review proposes the need for more preclinical evidence for the effects of fruit juices against different colon cancer cells, and also strives to facilitate clinical studies using these juices in humans in large trials. The conclusion of the review is that these apple and berry juices will be possible candidates in the campaign against colon cancer.

The red sport of 'Zaosu' pear and its red-striped pigmentation pattern are associated with demethylation of the PyMYB10 promoter

'Zaosu' pear, a hybrid of Pyrus pyrifolia and Pyrus communis, is a popular cultivar developed in China. 'Zaosu Red' is a bud sport of 'Zaosu' with red shoots, young leaves, and fruit. After grafting of 'Zaosu Red', reverse mutations in some branches lead to a loss of colour in leaves and stems. Also, the mature fruit of 'Zaosu Red' exhibits two phenotypes; fully red and striped. The aim of this study was to establish the mechanism of the red colour mutation in 'Zaosu' and the striped pigmentation pattern in fruit of 'Zaosu Red'. The accumulation of anthocyanins and transcript levels of the genes PpUFGT2 and PyMYB10 were highly correlated. The open reading frames (ORF) and promoter regions of these two key genes were cloned and compared between 'Zaosu' and its bud sports, but no sequence differences were found. The R2R3 MYB, PyMYB10, can activate expression of genes encoding enzymes of the anthocyanin biosynthetic pathway. A yeast one-hybrid assay showed that PyMYB10 was associated with the -658 to -172bp fragment of the PpUFGT2 promoter, probably via a MYB binding site (MBS) located at -466bp. The PyMYB10 promoter had lower methylation levels in anthocyanin-rich tissues, indicating that the red bud sport of 'Zaosu' pear and the striped pigmentation pattern of 'Zaosu Red' pear are associated with demethylation of the PyMYB10 promoter.

Phenolic composition and antioxidant activity of Malus domestica leaves

The aim of this study was to determine the composition and content of phenolic compounds in the ethanol extracts of apple leaves and to evaluate the antioxidant activity of these extracts. The total phenolic content was determined spectrophotometrically, as well as the total flavonoid content in the ethanol extracts of apple leaves and the antioxidant activity of these extracts, by the ABTS, DPPH, and FRAP assays. The highest amount of phenolic compounds and flavonoids as well as the highest antioxidant activity was determined in the ethanol extracts obtained from the apple leaves of the cv. Aldas. The analysis by the HPLC method revealed that phloridzin was a predominant component in the ethanol extracts of the apple leaves of all cultivars investigated. The following quercetin glycosides were identified and quantified in the ethanol extracts of apple leaves: hyperoside, isoquercitrin, avicularin, rutin, and quercitrin. Quercitrin was the major compound among quercetin glycosides.

Microarray analysis of cell cycle gene expression in adult human corneal endothelial cells

Corneal endothelial cells (ECs) form a monolayer that controls the hydration of the cornea and thus its transparency. Their almost nil proliferative status in humans is responsible, in several frequent diseases, for cell pool attrition that leads to irreversible corneal clouding. To screen for candidate genes involved in cell cycle arrest, we studied human ECs subjected to various environments thought to induce different proliferative profiles compared to ECs in vivo. Donor corneas (a few hours after death), organ-cultured (OC) corneas, in vitro confluent and non-confluent primary cultures, and an immortalized EC line were compared to healthy ECs retrieved in the first minutes of corneal grafts. Transcriptional profiles were compared using a cDNA array of 112 key genes of the cell cycle and analysed using Gene Ontology classification; cluster analysis and gene map presentation of the cell cycle regulation pathway were performed by GenMAPP. Results were validated using qRT-PCR on 11 selected genes. We found several transcripts of proteins implicated in cell cycle arrest and not previously reported in human ECs. Early G1-phase arrest effectors and multiple DNA damage-induced cell cycle arrest-associated transcripts were found in vivo and over-represented in OC and in vitro ECs. Though highly proliferative, immortalized ECs also exhibited overexpression of transcripts implicated in cell cycle arrest. These new effectors likely explain the stress-induced premature senescence that characterizes human adult ECs. They are potential targets for triggering and controlling EC proliferation with a view to increasing the cell pool of stored corneas or facilitating mass EC culture for bioengineered endothelial grafts.

Bioanalytical characterization of apple juice from 88 grafted and nongrafted apple varieties grown in Upper Austria

The compositional characteristics of untreated pure juice prepared from 88 apple varieties grown in the region of Eferding/Upper Austria were determined. Many of the analyzed varieties are noncommercial, old varieties not present in the market. The aim of the study was to quantitate the mineral, phosphate, trace elements, and polyphenolic content in order to identify varieties that are of particular interest for a wider distribution. Great variations among the investigated varieties could be found. This holds especially true for the total polyphenolic content (TPC) ranging from 103.2 to 2,275.6 mg/L. A clear dependence of the antioxidant capacity on the TPC levels was detected. Bioinformatics was employed to find specific interrelationships, such as Mg²⁺/Mn²⁺ and PO₄³⁻/K⁺, between the analyzed bio- and phytochemical parameters. Furthermore, special attention was drawn on putative effects of grafting on the phytochemical composition of apple varieties. By grafting 27 different apple varieties on two trees grown close to each other, it could be shown that the apple fruits remain their characteristic phytochemical composition. Finally, apple juice prepared from selected varieties was further characterized by additional biochemical analysis including cytotoxicity, epidermal growth factor receptor (EGFR) inhibition, and α-amylase activity tests. Cytotoxicity and inhibition of EGFR activation were found to be dependent on the TPC, while α-amylase activity was reduced by the apple juices independent of the presence of polyphenolic substances. Taken together selected apple varieties investigated within this study might serve as preferable sources for the development of apple-based food with a strong focus on health beneficial effects.

Site-specific anticancer effects of dietary flavonoid quercetin

Food-derived flavonoid quercetin, widely distributed in onions, apples, and tea, is able to inhibit growth of various cancer cells indicating that this compound can be considered as a good candidate for anticancer therapy. Although the exact mechanism of this action is not thoroughly understood, behaving as antioxidant and/or prooxidant as well as modulating different intracellular signalling cascades may all play a certain role. Such inhibitory activity of quercetin has been shown to depend first of all on cell lines and cancer types; however, no comprehensive site-specific analysis of this effect has been published. In this review article, cytotoxicity constants of quercetin measured in various human malignant cell lines of different origin were compiled from literature and a clear cancer selective action was demonstrated. The most sensitive malignant sites for quercetin revealed to be cancers of blood, brain, lung, uterine, and salivary gland as well as melanoma whereas cytotoxic activity was higher in more aggressive cells compared to the slowly growing cells showing that the most harmful cells for the organism are probably targeted. More research is needed to overcome the issues of poor water solubility and relatively low bioavailability of quercetin as the major obstacles limiting its clinical use.

Sweet tea leaves extract improves leptin resistance in diet-induced obese rats

AIM OF THE STUDY

Dietary obesity is usually characterized by leptin resistance and abnormal lipid metabolism. Lithocarpus polystachyus Rehd.(Sweet Tea) leaf is a kind of Chinese folkloric medicine, and it has been widely used for obesity, diabetes, and hypertension in South China. The present study is aimed at investigating the pharmacological mechanism of the anti-hyperleptinaemia effects of Sweet Tea leaves extract in high fat diet-induced obese rats.

MATERIALS AND METHODS

We induced high fat diet obesity for 14 weeks to test the corrective effects of three ST doses (75, 150 and 300 mg/kg per day) for 8 weeks. At the end of the experiment, body weight, fasting blood glucose and serum lipids, superoxide dismutase (SOD), malondialdehyde (MDA), fasting serum insulin and leptin, C-reactive protein, adiponectin and resistin levels were measured, Homeostasis Model Assessment for Insulin Resistance (HOMA-IR) was also calculated. mRNA gene expression of PPARγ (peroxisome proliferator-activated receptor γ) and C/EBPα(CCAAT/enhancer-binding protein α) in epididymal adipose tissue of DIO control and experimental groups were evaluated.

RESULTS

Sweet Tea leaves extract could significantly decrease the levels of serum lipids, attenuate body weight gain and lower circulating leptin and insulin levels, ameliorate the state of oxidative stress, raise serum adiponectin, reduce circulating CRP and resistin levels, and depress the expression of PPARγ and C/EBPα in epididymal adipose tissue of obese rats.

CONCLUSION

The present findings suggest that ST can effectively attenuate the leptin resistance at least through anti-hyperlipidemic activity and thus has the therapeutic potential in treating hyperlipidemia and hyperleptinaemia related to dietary obesity.