Chelate-soluble pectin fraction from papaya pulp interacts with galectin-3 and inhibits colon cancer cell proliferation

Assessing high-temperature and pressure extraction of bioactive water-soluble polysaccharides from passion fruit mesocarp

The mesocarp (albedo) of passion fruit is considered a waste product but rich in soluble fibers, especially pectins. Biological activity and health benefits of pectins have recently emerged, especially in colorectal cancer and attenuating inflammation. Pectin conventional extraction often uses mineral acids, which can be hazardous to the environment, and alternatives can be costly. Here, we assessed a high-temperature and pressure method to extract pectin from the passion fruit albedo and evaluated the differences from the water-soluble fractions extracted. HPSEC, HPAEC, FTIR-ATR, and HSQC-NMR were performed to identify and confirm the highly methylated homogalacturonan structures. The heat-modified samples showed a decreased molecular size compared to the untreated sample. Colorectal cancer cell lines showed reduced viability after being treated with different doses of modified samples, with two of them, LW-MP3 and 4, showing the most potent effects. All samples were detected inside cells by immunofluorescence assay. It was observed that LW-MP3 and 4 upregulated the p53 protein, indicating cell-cycle arrest and the cleaved caspase-9 in one of the cell lines, with LW-MP4 enhancing cell death by apoptosis. Since the modified samples were composed of hydrolyzed homogalacturonans, those probably were the responsible structures for these anti-cancer effects.

Dietary fiber as a wide pillar of colorectal cancer prevention and adjuvant therapy

Colorectal cancer is the third most incident and second most lethal type of cancer worldwide. Lifestyle and dietary patterns are the key factors for higher disease development risk. The dietary fiber intake from fruits and vegetables, mainly formed by food hydrocolloids, can help to lower the incidence of this type of neoplasia. Different food polysaccharides have applications in anti-tumoral therapy, such as coadjuvant to mainstream drugs, carriage-like properties, or direct influence on tumoral cells. Some classes include inulin, β-glucans, pectins, fucoidans, alginates, mucilages, and gums. Therefore, it is fundamental to discuss colorectal cancer mechanisms and the roles played by different polysaccharides in intestinal health. Genetic, environmental, and immunological modulation of mutated pathways regarding colorectal cancer has been explored before. Microbial diversity, byproduct formation (primarily short-chain fatty acids), inflammatory profile control, and tumoral mutated pathways regulation are thoroughly explored mechanisms by which dietary fiber sources influence a healthy gut ambiance.

Ripe papaya pectins inhibit the proliferation of colon cancer spheroids and the formation of chemically induced aberrant crypts in rats colons

Pectins are a class of soluble polysaccharides that can have anticancer properties through several mechanisms. This study aimed to characterize the molecular structure of water-soluble fractions (WSF) derived from ripe and unripe papayas and assess their biological effects in two models: the 3D colon cancer spheroids to measure cell viability and cytotoxicity, and the in vivo model to investigate the inhibition of preneoplastic lesions in rats. WSF yield was slightly higher in ripe papaya, and both samples mainly consisted of pectin. Both pectins inhibited the growth of colon cancer HT29 and HCT116 spheroids. Unripe pectin disturbed HT29/NIH3T3 spheroid formation, decreased HCT116 spheroid viability, and increased spheroid cytotoxicity. Ripe pectin had a more substantial effect on the reduction of spheroid viability for HT29 spheroids. Furthermore, in vivo experiments on a rat model revealed a decrease in aberrant crypt foci (ACF) formation for both pectins and increased apoptosis in colonocytes for ripe papaya pectins. The results suggest potential anticancer properties of papaya pectin, with ripe pectin showing a higher potency.

Purification and structural characterization of two polysaccharides with anti-inflammatory activities from Plumbago zeylanica L

Plumbago zeylanica L., a traditional Chinese medicine, has anti-bacterial and anti-inflammatory effects, and it is critical important to explore the chemical compounds and evaluate their biological actions from the medicinal plant. However, the chemical structure and biological activities of polysaccharides from P. zeylanica. were still poorly understood. In this study, two water-soluble polysaccharides named WPZP-2-1 and WPZP-2-2 were purified from P. zeylanica L. Chemical and spectroscopic tests showed that the main chain of WPZP-2-1 was →4)-α-D-GalpA-(1 → 2)-α-L-Rhap-(1→, and the branch chain was galactose or arabinose. The main chain of WPZP-2-2 was composed of →4)-α-D-GalpA-(1 → 2)-α-L-Rhap-(1→, and the O-2 and O-3 of →4)-α-D-GalpA had a small amount of acetylation. In addition, in vitro test showed that WPZP-2-1 and WPZP-2-2 significantly improved the inflammatory damage of LPS + IFN-γ-induced THP-1 cells via reducing the protein levels of CD14, TLR4 and MyD88, thereby promoting IL-10 expression and inhibiting the mRNA levels of TNF-α and IL-1β. Those findings indicated that WPZP-2-1 and WPZP-2-2 from the plant should be served as the potential anti-inflammatory agents.

Pectin a multifaceted biopolymer in the management of cancer: A review

This review article focuses on the multifaceted roles of pectin in cancer management, namely as an oncotherapeutic delivery vehicle and a pharmacological agent. Over the past decades, the potential of pectin as a novel therapeutical agent for the prevention and/or management of cancer has gained increasing interest. Pectin has been found to modulate different mechanisms involved in the onset and progression of carcinogenesis, such as galectin-3 inhibition, caspase-3-induced apoptosis, and autophagy. Elucidating the structure-activity relationship provides insight into the relationship between the structure of pectin and different mechanism/s. The bioactivity of pectin, with respect to its structure, was critically discussed to give a better insight of the relationship between the structure of the extracted pectin and the observed bioactive effects. The rhamnogalacturonan I part of the pectin chain was found to bind to galectin-3, associated with several cancer hallmarks. The anti-inflammatory and antioxidant potential of pectin were also described. The roles of pectin as a treatment enhancer and a drug delivery vehicle for oncotherapeutics were critically defined. The scientific findings presented in this paper are expected to highlight the potential and role of pectin recovered from various plant sources in preventing and managing cancer.

Potential role of cell wall pectin polysaccharides, water state, and cellular structure on twice "increase-decrease" texture changes during kohlrabi pickling process

Pickled kohlrabi is a traditional and favored vegetable product in China. During pickling, the hardness, springiness, and chewiness of kohlrabi all experienced a typical change with twice "increase-decrease" trend. However, little is known about its mechanism. In this study, in situ analysis including immunofluorescence, low field nuclear magnetic, and transmission electron microscopy were used to explore the effects of cell wall pectin, water state, and cellular structure on kohlrabi texture changes during pickling. Results revealed that at the early stage, due to the rapid loss of water after three times salting, the cells shrank and the interstitial space reduced, resulting in the first increase on kohlrabi texture. Subsequently, the dehydration-rehydration caused by the first brine processing resulted in the first decrease on kohlrabi texture. Then under the action of PME enzyme, more low-esterified pectin was produced, and chelate-soluble pectin with more branched structure was further formed, leading to another elevation of the sample texture. As the pickling continued, under the combined action of PG and PME, the molecular weight of pectin was decreased and the rigidity of the cell tissue was destroyed, caused kohlrabi texture continued to decline. These researches could provide important information and guidance for better maintaining the texture of pickled vegetables during processing.

Anticancer potential of Carica papaya Linn black seed extract against human colon cancer cell line: in vitro study

BACKGROUND

Since cancer is one of the most prevalent diseases in the world, further studies are needed to identify the effective therapeutic modalities. The second deadliest and third most common cancer is colorectal cancer (CRC). Papaya (Carica papaya Linn) seeds offer anti-cancer properties that can cure various types of cancer, such as liver and prostate cancer.

METHODS

The study aimed to evaluate the anti-cancer activity of Carica papaya seed extract on colorectal cancer cell lines (Caco-2) and used techniques to assess the anti-cancer potential. The effectiveness of SE on cell proliferation and the viability of HTB-37 Caco-2 and C-166 cells were assessed using the MTT test. Real-time RT-PCR was used to measure gene expression levels and evaluate the activity of genes involved in apoptosis, including caspase-3, p53, Cycs, and Bcl-2. Finally, flow cytometry was used to analyze apoptosis induction by detecting changes in cell morphology and DNA content.

RESULTS

The study showed that the MTT reduction assay was dependent on cancer cell type and concentration of SE compared to the control cells and C-166, with a mean IC₅₀ value of 9.734 ug/ml. The cytotoxicity was accompanied by some morphological alterations in the colorectal cancer cell line (Caco-2). The expression of the genes for p53, Cycs, and caspase-3 was substantially up-regulated, while Bcl-2 was dramatically down-regulated compared to control cells. The cell cycle arrested at the G2-M phase and the presence of early and late apoptotic characteristics post-treatment increased the apoptotic profile.

CONCLUSION

It concluded that papaya seeds aqueous extract could act as a novel therapeutic option for colorectal cancer (CRC).

Structural Characteristic and In-Vitro Anticancer Activities of Dandelion Leaf Polysaccharides from Pressurized Hot Water Extraction

Dandelion (Taraxacum mongolicum Hand.-Mazz.) is a medicinal and edible plant. Dandelion has great development value for its health promoting benefits; additionally, Dandelion grows almost anywhere in the world. In this study, we report the structural characteristics and anti-cancer activity of novel dandelion leaf polysaccharides extracted by pressurized hot water extraction at 120 °C (DLP120) with Mw relative to dextran of 1.64 × 10⁶ Da. Structural analysis indicated that DLP120 is a complex polysaccharide composed of pectin and arabinogalactan. It was mainly composed of arabinose (32.35 mol%) and galactose (44.91 mol%). The main glycosidic linkages of DLP120 were 4-β-D-Galp, 4-α-D-GalpA, T-β-D-Galp, 5-α-L-Araf, 3,5-α-L-Araf, and T-α-L-Araf. In vitro, DLP120 inhibited HepG2 cell proliferation in a dose-dependent manner by inducing cell apoptosis. Cell cycle detection results revealed that DLP120 mainly arrests the cell cycle in S phase. Cells treated with DLP120 displayed obvious apoptotic morphology, including cell volume shrinks and cytoskeleton breaks down. In short, DLP120 has potential as an anti-cancer agent.

An Overview of Antitumour Activity of Polysaccharides

Cancer incidence and mortality are rapidly increasing worldwide; therefore, effective therapies are required in the current scenario of increasing cancer cases. Polysaccharides are a family of natural polymers that hold unique physicochemical and biological properties, and they have become the focus of current antitumour drug research owing to their significant antitumour effects. In addition to the direct antitumour activity of some natural polysaccharides, their structures offer versatility in synthesizing multifunctional nanocomposites, which could be chemically modified to achieve high stability and bioavailability for delivering therapeutics into tumor tissues. This review aims to highlight recent advances in natural polysaccharides and polysaccharide-based nanomedicines for cancer therapy.

Structure of a new glycyrrhiza polysaccharide and its immunomodulatory activity

A component of licorice polysaccharide (GPS-1) was extracted from licorice, its primary structure was identified and characterized for the first time, and its immunomodulatory activity was studied. Crude licorice polysaccharide was isolated and purified by DEAE sepharose FF ion-exchange column chromatography and Chromdex 200 PG gel filtration column chromatography to obtain a purified Glycyrrhiza polysaccharide named GPS-1. NMR and methylation analysis revealed that GPS-1 is composed of homogalacturonan (HG)-type pectin with 4)-D-GalpA-(1 as the backbone. This study of GPS-1 also examined its significant role in regulating immune activity in vitro and in vivo. As a result, GPS-1 promoted the secretion of IFN-γ and IL-4 in mice and increased the proportion of CD3+CD4+ and CD3+CD8+ T lymphocytes in their spleens. Dendritic cells (DCs) treated with GPS-1 showed promotion of DC maturation, antigen presentation, and phagocytic capacity. The results suggest that GPS-1 is a potential immunomodulator that stimulates the immune system by regulating multiple signaling pathways. Combined with our characterization of the primary structure of GPS-1, the present investigation provides the basis for future study of the form-function relationship of polysaccharides.

The Use of Endo-Cellulase and Endo-Xylanase for the Extraction of Apple Pectins as Factors Modifying Their Anticancer Properties and Affecting Their Synergy with the Active Form of Irinotecan

Pectin constitutes an essential component of dietary fiber. Modified pectins from various sources possess potent anticancer and immunomodulatory activities. In this study, two pectins isolated from apple pomace by Trichoderma enzyme treatment, PX (with endo-xylanase) and PCX (with both endo-cellulase and endo-xylanase), were studied in colon cancer cell lines (HCT 116, Caco-2, and HT-29). Both pectins reduced colon cancer cell viability, induced apoptosis, and increased intracellular amounts of reactive oxygen species. Additionally, synergy between pectin and an active form of irinotecan, SN-38, in all aspects mentioned above, was discovered. This drug is a common component of cytotoxic combinations recommended as treatment for colon cancer patients. PX and PCX demonstrated significant anti-inflammatory activity in lipopolysaccharide-stimulated cells. Interaction of apple pectins with galectin-3 and Toll-like Receptor 4 (TLR4) was suggested to be responsible for their anticancer and anti-inflammatory effect. Since PCX was more active than PX in almost all experiments, the role of the enzyme used to obtain the pectin for its biological activity was discussed. It was concluded that co-operation between both enzymes was needed to obtain the molecule of the most beneficial properties. The low molecular mass of PCX together with a high proportion of rhamnogalacturonan I (RG I) regions seemed to be crucial for its superior activity.

Papaya (Carica papaya L.) for cancer prevention: Progress and promise

Cancer is a leading cause of morbidity and mortality across the globe. Emerging evidence suggests that consumption of a well-balanced diet containing a wide variety of vegetables, fruits, and whole grains can prevent the development of, halt, or reverse cancer progression. Carica papaya L. (papaya) has a wide distribution throughout many countries. Although the fruits of C. papaya are primarily consumed as food, various parts of this tree, including the bark, fruits, latex, seeds, and roots, have been used in traditional medicine for health promotion and disease mitigation. While numerous individual studies have investigated anticancer efficacies of various products and constituents of C. papaya, an up-to-date, comprehensive, and critical evaluation of available research data covering its role in the prevention and intervention of various human malignancies has not been conducted according to our knowledge. The purpose of this review is to present a systematic, comprehensive, and critical analysis of the cancer-preventive potential of C. papaya extracts, fractions, and isolated phytochemicals with a special emphasis on the cellular and molecular mechanisms of action. Moreover, the bioavailability, pharmacokinetics, and safety profiles of individual phytochemicals of C. papaya, as well as current limitations, challenges, and future directions of research, have also been discussed.

Structural features and anticancer mechanisms of pectic polysaccharides: A review

The anticancer activity of pectic polysaccharides (PPs) was proved by numerous studies, and which also indicated that the bioactivity of PPs was closely related to its complicated structures. Based on the summary and analysis about structure characteristics and corresponding enzymatic process of the reported PPs, the anticancer mechanism and related structural features were systematically clarified. It was found that not only the direct effects on the cancer cells by proliferation inhibition or apoptosis, but also the regulation of immune system, gut microbiota and gut metabolism as indirect effects, jointly played important roles in the anticancer of PPs. Nevertheless, during the study of PPs as promising anticancer components, the exact structure-function relationship, digestion process in vivo, and comprehensive action mechanism are still not well understanding. With the unveiling of the proposed issues, it is believed that PPs are promising to be exploited as effective cancer therapy/adjunctive therapy drugs or functional foods.

The Complex Biological Effects of Pectin: Galectin-3 Targeting as Potential Human Health Improvement?

Galectin-3 is the only chimeric representative of the galectin family. Although galectin-3 has ubiquitous regulatory and physiological effects, there is a great number of pathological environments where galectin-3 cooperatively participates. Pectin is composed of different chemical structures, such as homogalacturonans, rhamnogalacturonans, and side chains. The study of pectin's major structural aspects is fundamental to predicting the impact of pectin on human health, especially regarding distinct molecular modulation. One of the explored pectin's biological activities is the possible galectin-3 protein regulation. The present review focuses on revealing the structure/function relationship of pectins, their fragments, and their biological effects. The discussion highlighted by this review shows different effects described within in vitro and in vivo experimental models, with interesting and sometimes contradictory results, especially regarding galectin-3 interaction. The review demonstrates that pectins are promissory food-derived molecules for different bioactive functions. However, galectin-3 inhibition by pectin had been stated in literature before, although it is not a fully understood, experimentally convincing, and commonly agreed issue. It is demonstrated that more studies focusing on structural analysis and its relation to the observed beneficial effects, as well as substantial propositions of cause and effect alongside robust data, are needed for different pectin molecules' interactions with galectin-3.

Pectic polysaccharide from Smilax china L. ameliorated ulcerative colitis by inhibiting the galectin-3/NLRP3 inflammasome pathway

Ulcerative colitis (UC) is an inflammatory bowel disease that affects the colon and rectum. Although galectin-3 (Gal-3) has been reported to play a proinflammatory role in UC, it is unknown whether pectic polysaccharide, a Gal-3 inhibitor in tumor metastasis, can alleviate UC by inhibiting Gal-3. The aim of this study was to investigate the anti-inflammatory effects and underlying mechanisms of SCLP, a pectic polysaccharide purified from Smilax china L. in our previous work, on dextran sulfate sodium-induced UC in BALB/c mice. The results showed that SCLP could significantly improve symptoms, alleviate histopathological damage and reduce the secretion of inflammatory mediators in mice with UC. Analysis of the anti-colitis mechanisms indicated that SCLP could inhibit the Gal-3/NLRP3 inflammasome/IL-1β pathway by suppressing the expression of Gal-3 and the interaction of Gal-3 and NLRP3. Our results suggested that SCLP could be a promising candidate for prevention and treatment of UC.

Anti-Cancer Pectins and Their Role in Colorectal Cancer Treatment

A class of plant polysaccharides, pectin is known to display several medicinal properties including in cancer. There is some evidence that pectin from some fruits can reduce the severity of colorectal cancer (CRC) due to its antiproliferative, anti-inflammatory, antimetastatic and pro-apoptotic properties. Pectin fermentation in the colon induces antiproliferative activity via butyrate. Research also showed that pectin acts as a potent inducer of programmed cell death and cell-cycle arrest, thereby selectively targeting cancer cells. Pectin can limit oxidative stress to maintain cellular homeostasis while increasing reactive oxygen species damage to activate cancer cell death. Pectin regulates various signaling cascades, e.g., signal transduction and transcriptional activator and mitogen-activated protein kinase signaling, that contribute to its anticancer activity. By curbing inflammation-activated signaling and bolstering immune-protective mechanisms pectin can eradicate CRC. Due to its chemical structure, pectin can also inhibit galectin-3 and suppress tumor growth and metastasis. Prior reports also suggested that pectin is beneficial to use alongside the CRC standard care. Pectin can increase sensitivity to conventional CRC drugs, alleviate unwanted side effects and reduce drug resistance. Although some preclinical studies are promising, early clinical trials are showing some evidence for pectin's efficacy in tumor growth inhibition and preventing metastasis in some cancers; however, the clinical use of pectin in CRC therapy is not yet well established. Further studies are needed to confirm the efficacy of pectin treatment as a valid clinical therapy for CRC in humans.

Pharmacological potentials and Nutritional values of Tropical and Sub-tropical Fruits of India: Emphasis on their anticancer bioactive components

BACKGROUND

Fruits are an important dietary component, which supply vitamins, minerals, as well as dietary fiber. In addition, they are rich sources of various biological and pharmacologically active compounds. Among these, temperate fruits are well studied for their pharmacological potentials, whereas tropical/subtropical fruits are less explored for their health impacts. In India, most of the consumed fruits are either tropical or subtropical.

OBJECTIVES

The present review aims to provide a health impact of major tropical and sub-tropical fruits of India, emphasizing their anticancer efficacy. In addition, the identified bioactive components from these fruits exhibiting anticancer efficacy are also discussed along with the patent literature published.

METHODS

The literature was collected from various repositories, including NCBI, ScienceDirect, Eurekaselect, and Web of Science; literature from predatory journals was omitted during the process. Patent literature was collected from google patents and similar patent databases.

RESULTS

Tropical fruits are rich sources of various nutrients and bioactive components including polyphenols, flavonoids, anthocyanin, etc. By virtue of these biomolecules, tropical fruits have been shown to interfere with various steps in carcinogenesis, metastasis, and drug resistance. Their mode of action is either by activation of apoptosis, regulation of cell cycle, inhibition of cell survival and proliferation pathways, increased lipid trafficking or inhibiting inflammatory pathways. Several molecules and combinations have been patented for their anticancer and chemoprotective properties.

CONCLUSION

Overall, the present concludes that Indian tropical/ subtropical fruits are nutritionally and pharmacologically active and may serve as a source of novel anticancer agents in the future.

Recent advances in utilization of pectins in biomedical applications: a review focusing on molecular structure-directing health-promoting properties

The numerous health benefits of pectins justify their inclusion in human diets and biomedical products. This review provides an overview of pectin extraction and modification methods, their physico-chemical characteristics, health-promoting properties, and pharmaceutical/biomedical applications. Pectins, as readily available and versatile biomolecules, can be tailored to possess specific functionalities for food, pharmaceutical and biomedical applications, through judicious selection of appropriate extraction and modification technologies/processes based on green chemistry principles. Pectin's structural and physicochemical characteristics dictate their effects on digestion and bioavailability of nutrients, as well as health-promoting properties including anticancer, immunomodulatory, anti-inflammatory, intestinal microflora-regulating, immune barrier-strengthening, hypercholesterolemia-/arteriosclerosis-preventing, anti-diabetic, anti-obesity, antitussive, analgesic, anticoagulant, and wound healing effects. HG, RG-I, RG-II, molecular weight, side chain pattern, and degrees of methylation, acetylation, amidation and branching are critical structural elements responsible for optimizing these health benefits. The physicochemical characteristics, health functionalities, biocompatibility and biodegradability of pectins enable the construction of pectin-based composites with distinct properties for targeted applications in bioactive/drug delivery, edible films/coatings, nano-/micro-encapsulation, wound dressings and biological tissue engineering. Achieving beneficial synergies among the green extraction and modification processes during pectin production, and between pectin and other composite components in biomedical products, should be key foci for future research.

Pectin in biomedical and drug delivery applications: A review

Natural macromolecules have attracted increasing attention due to their biocompatibility, low toxicity, and biodegradability. Pectin is one of the few polysaccharides with biomedical activity, consequently a candidate in biomedical and drug delivery Applications. Rhamnogalacturonan-II, a smaller component in pectin, plays a major role in biomedical activities. The ubiquitous presence of hydroxyl and carboxyl groups in pectin contribute to their hydrophilicity and, hence, to the favorable biocompatibility, low toxicity, and biodegradability. However, pure pectin-based materials present undesirable swelling and corrosion properties. The hydrophilic groups, via coordination, electrophilic addition, esterification, transesterification reactions, can contribute to pectin's physicochemical properties. Here the properties, extraction, and modification of pectin, which are fundamental to biomedical and drug delivery applications, are reviewed. Moreover, the synthesis, properties, and performance of pectin-based hybrid materials, composite materials, and emulsions are elaborated. The comprehensive review presented here can provide valuable information on pectin and its biomedical and drug delivery applications.

[Expression and Clinical Significance of Galcetin-3 in the Serum of Non-small Cell Lung Cancer Patients]

背景与目的

肺癌是对人类健康威胁最大的疾病之一, 发病率高, 死亡率高。早期肺癌可以通过外科手术得到根治, 因此, 肺癌的早期发现及早期治疗尤其重要。血清肿瘤标志物是发现及诊断肺癌的一个重要手段。目前已知, 半乳糖凝集素3(Galectin-3)在多种恶性肿瘤中均有表达。该研究旨在探讨Galectin-3在非小细胞肺癌患者血清中的表达水平及其临床意义。

方法

采用酶联免疫吸附法检测并比较69例非小细胞肺癌患者与77例健康人群外周血血清Galectin-3浓度, 并分析其表达水平与肺癌临床特征之间的关系。

结果

Galectin-3在非小细胞肺癌患者外周血血清中的表达水平高于健康人群, 差异具有显著统计学意义(P < 0.01)；有淋巴结转移的非小细胞肺癌患者, Galectin-3表达水平显著高于无淋巴结转移患者, 差异有显著统计学意义(P < 0.01)；N2淋巴结转移的患者Galectin-3表达水平显著高于N1淋巴结转移的患者, 差异有显著统计学意义(P < 0.01)；临床Ⅲ期+Ⅳ期患者Galectin-3表达水平显著高于临床Ⅰ期+Ⅱ期患者, 差异有统计学意义(P < 0.05)。

结论

非小细胞肺癌患者血清Galectin-3水平呈现高表达, 与肺癌转移相关, 可能是一种潜在的肺癌肿瘤标志物。

Modulation of human gut microbiota by dietary fibers from unripe and ripe papayas: Distinct polysaccharide degradation using a colonic in vitro fermentation model

Dietary fibers (DFs) consumption promotes a healthier gut through colonic fermentation and the modulation of different types of gut bacteria. The aim of this study is to evaluate the production of short-chain fatty acids (SCFA), metabolization of polysaccharides, and changes in the bacterial profile related to DFs extracted from the pulp of unripe and ripe papayas, using a batch colonic in vitro fermentation model. Our results show that fermentation of DFs from papayas induce the production of SCFAs and are utilized in different ways by intestinal microbiota. DFs from ripe papayas showed faster degradation by human gut microorganisms due to higher level of water-soluble polysaccharides. The fermentation of unripe papaya fibers increased the abundance of microorganisms belonging to family Clostridiaceae and genera Coprobacillus, Bulleidia, and Slackia, whereas both fibers increased Clostridium and Bacteroides, showing fruit ripeness affects the fermentation pattern of fruit fibers and their probable beneficial health aspects.

The purification of pectin from commercial fruit flours results in a jaboticaba fraction that inhibits galectin-3 and colon cancer cell growth

Fruits are a prime source of nutrients, bioactive compounds, and dietary fibers. Some products available on the Brazilian market use fruit by-products and claim to have useful effects on human health due to their dietary fiber content. The study aimed to extract and purify the total (28-47 w/w yield) and soluble dietary fiber (4-7 w/w yield) from jaboticaba, papaya, and plum commercial flours sold in Brazil and to study the in vitro biological effects of the fractions. The purified water-soluble fractions consisted mainly of pectin-derived oligosaccharides (5-15 KDa molecular weight) with a negligible content of polyphenols, protein, ashes, and starch. Jaboticaba sample was 95% galacturonic acid while plum and papaya samples were 40% galacturonic acid and 40% galactose (mol%), approximately. The samples were tested for recombinant human galectin-3 inhibition and changes in the cell viability of human colorectal cancer cells. Only the jaboticaba sample inhibited galectin-3 and decreased HCT116 cell viability after 48 h of treatment (p ≤ 0.01) while the plum sample decreased the cell viability after 24 h treatment (p ≤ 0.05). The results obtained in this study demonstrate the relationship between the structure of the soluble fibers extracted from jaboticaba flour and the possible beneficial effects of their consumption.

Prognostic value of serum aquaporin-1, aquaporin-3 and galectin-3 for young patients with colon cancer

BACKGROUND

This study aimed to investigate the long-term prognosis value of serum galectin-3, aquaporin (AQP)-1 and AQP-3 in young patients with colon cancer.

METHODS

A total of 100 young patients with colon cancer, 100 cases of benign colon and 100 healthy people were collected. All colon cancer patients were followed up for 42 months.

RESULTS

Compared with the benign lesion group and the control group, preoperative serum galectin-3, AQP-1 and AQP-3 concentrations were significantly increased in patients with colon cancer (P < 0.05). The immunohistochemistry scores of galectin-3, AQP-1 and AQP-3 in colon cancer patients were positively correlated with serum galectin-3, AQP-1 and AQP-3 concentrations (P < 0.05). Serum galectin-3, AQP-1 and AQP-3 concentrations were positively correlated with TNM staging (galectin-3: r_Pearson = 0.502, P < 0.001; AQP-1: r_Pearson = 0.415, P < 0.001; AQP-3: r_Pearson = 0.454, P < 0.001) and differentiation (galectin-3: r_Pearson = 0.377, P = 0.004; AQP-1: r_Pearson = 0.411, P = 0.001; AQP-3: r_Pearson = 0.483, P < 0.001). Receiver operator characteristic curve (ROC) analysis showed that the area under ROC curve (AUC) of the combination of galectin-3, AQP-1 and AQP-3 in distinguishing colon cancer was 0.907. The sensitivity in the parallel mode was 87.6%, and the specificity in the serial mode was 98.2%. Compared with the low galectin-3 group, low AQP-1 group and low AQP-3 group, the survival time of patients in the high galectin-3 group (χ² = 13.929, P < 0.001), high AQP-1 group (χ² = 10.157, P = 0.001) and high AQP-3 group (χ² = 4.364, P = 0.037) were significantly shortened.

CONCLUSION

Galectin-3 combined with AQP-1 and AQP-3 had important value in the identification of young patients with colon cancer and was of great value in evaluating long-term prognosis.

RETRACTED: Residual papaya promoting the growth performance, antioxidant, nonspecific immunity of juvenile Tilapia mossambica

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of Editors-in-Chief and first Author. The article duplicates significant parts of a paper that had already appeared in Fish & Shellfish Immunology, Volume 93 (2019) 726-731, https://doi.org/10.1016/j.fsi.2019.06.052. One of the conditions of submission of a paper for publication is that authors declare explicitly that the paper has not been previously published and is not under consideration for publication elsewhere. As such this article represents a misuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process. The article was published without the knowledge of the co-authors.

Pectin Interaction with Immune Receptors is Modulated by Ripening Process in Papayas

Dietary fibers have been shown to exert immune effects via interaction with pattern recognition receptors (PRR) such as toll-like receptors (TLR) and nucleotide-binding oligomerization domain (NOD)-like receptors. Pectin is a dietary fiber that interacts with PRR depending on its chemical structure. Papaya pectin retains different chemical structures at different ripening stages. How this influence PRR signaling is unknown. The aim of this work was to determine how ripening influences pectin structures and their ability to interact with TLR2, 3, 4, 5 and 9, and NOD1 and 2. It was evaluated the interaction of the water-soluble fractions rich in pectin extracted from unripe to ripe papayas. The pectin extracted from ripe papayas activated all the TLR and, to a lesser extent, the NOD receptors. The pectin extracted from unripe papayas also activated TLR2, 4 and 5 but inhibited the activation of TLR3 and 9. The differences in pectin structures are the higher methyl esterification and smaller galacturonan chains of pectin from ripe papayas. Our finding might lead to selection of ripening stages for tailored modulation of PRR to support or attenuate immunity.

Ingestion of Non-digestible Carbohydrates From Plant-Source Foods and Decreased Risk of Colorectal Cancer: A Review on the Biological Effects and the Mechanisms of Action

The hypothesis that links the increase in the intake of plant-source foods to a decrease in colorectal cancer (CRC) risk has almost 50 years. Nowadays, systematic reviews and meta-analysis of case-control and cohort studies confirmed the association between dietary patterns and CRC risk, in which the non-digestible carbohydrates (NDC) from plant-source foods are known to play beneficial effects. However, the mechanisms behind the physicochemical properties and biological effects induced by NDC on the decrease of CRC development and progression remain not fully understood. NDC from plant-source foods consist mainly of complex carbohydrates from plant cell wall including pectin and hemicellulose, which vary among foods in structure and in composition, therefore in both physicochemical properties and biological effects. In the present review, we highlighted the mechanisms and described the recent findings showing how these complex NDC from plant-source foods are related to a decrease in CRC risk through induction of both physicochemical effects in the gastrointestinal tract, fermentation-related effects, and direct effects resulting from the interaction between NDC and cellular components including toll-like receptors and galectin-3. Studies support that the definition of the structure-function relationship-especially regarding the fermentation-related effects of NDC, as well as the direct effects of these complex carbohydrates in cells-is crucial for understanding the possible NDC anticancer effects. The dietary recommendations for the intake of NDC are usually quantitative, describing a defined amount of intake per day. However, as NDC from plant-source foods can exert effects that vary widely according to the NDC structure, the dietary recommendations for the intake of NDC plant-source foods are expected to change from a quantitative to a qualitative perspective in the next few years, as occurred for lipid recommendations. Thus, further studies are necessary to define whether specific and well-characterized NDC from plant-source foods induce beneficial effects related to a decrease in CRC risk, thereby improving nutritional recommendations of healthy individuals and CRC patients.

Fast and Furious: Ethylene-Triggered Changes in the Metabolism of Papaya Fruit During Ripening

Papaya is a climacteric fleshy fruit characterized by fast ripening after harvest. During the relatively short postharvest period, papaya fruit undergoes several changes in metabolism that result in pulp softening and sweetening, as well as the development of a characteristic aroma. Since papaya is one of the most cultivated and appreciated tropical fruit crops worldwide, extensive research has been conducted to not only understand the formation of the quality and nutritional attributes of ripe fruit but also to develop methods for controlling the ripening process. However, most strategies to postpone papaya ripening, and therefore to increase shelf life, have failed to maintain fruit quality. Ethylene blockage precludes carotenoid biosynthesis, while cold storage can induce chilling injury and negatively affect the volatile profile of papaya. As a climacteric fruit, the fast ripening of papaya is triggered by ethylene biosynthesis. The generation of the climacteric ethylene positive feedback loop is elicited by the expression of a specific transcription factor that leads to an up-regulation of 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (ACS) and ACC-oxidase (ACO) expression, triggering the system II ethylene biosynthesis. The ethylene burst occurs about 3 to 4 days after harvest and induces pectinase expression. The disassembling of the papaya cell wall appears to help in fruit sweetness, while glucose and fructose are also produced by acidic invertases. The increase in ethylene production also results in carotenoid accumulation due to the induction of cyclases and hydroxylases, leading to yellow and red/orange-colored pulp phenotypes. Moreover, the production of volatile terpene linalool, an important biological marker for papaya's sensorial quality, is also induced by ethylene. All these mentioned processes are related to papaya's sensorial and nutritional quality. We describe the understanding of ethylene-triggered events that influence papaya quality and nutritional traits, as these characteristics are a consequence of an accelerated metabolism during fruit ripening.