Peptides in common bean fractions inhibit human colorectal cancer cells

Recent progress in the preparation of bioactive peptides using simulated gastrointestinal digestion processes

Bioactive peptides (BAPs) represent a unique class of peptides known for their extensive physiological functions and their role in enhancing human health. In recent decades, owing to their notable biological attributes such as antioxidant, antihypertensive, antidiabetic, and anti-inflammatory activities, BAPs have received considerable attention. Simulated gastrointestinal digestion (SGD) is a technique designed to mimic physiological conditions by adjusting factors such as digestive enzymes and their concentrations, pH levels, digestion duration, and salt content. Initially established for analyzing the gastrointestinal processing of foods or their constituents, SGD has recently become a preferred method for generating BAPs. The BAPs produced via SGD often exhibit superior biological activity and stability compared with those of BAPs prepared via other methods. This review offers a comprehensive examination of the recent advancements in BAP production from foods via SGD, addressing the challenges of the method and outlining prospective directions for further investigation.

Gastrointestinal digestion of food proteins: Anticancer, antihypertensive, anti-obesity, and immunomodulatory mechanisms of the derived peptides

Food proteins and their peptides play a significant role in the important biological processes and physiological functions of the body. The peptides show diverse biological benefits ranging from anticancer to antihypertensive, anti-obesity, and immunomodulatory, among others. In this review, an overview of food protein digestion in the gastrointestinal tract and the mechanisms involved was presented. As some proteins remain resistant and undigested, the multifarious factors (e.g. protein type and structure, microbial composition, pH levels and redox potential, host factors, etc.) affecting their colonic fermentation, the derived peptides, and amino acids that evade intestinal digestion are thus considered. The section that follows focuses on the mechanisms of the peptides with anticancer, antihypertensive, anti-obesity, and immunomodulatory effects. As further considerations were made, it is concluded that clinical studies targeting a clear understanding of the gastrointestinal stability, bioavailability, and safety of food-based peptides are still warranted.

Bioactive peptides: an alternative therapeutic approach for cancer management

Cancer is still considered a lethal disease worldwide and the patients' quality of life is affected by major side effects of the treatments including post-surgery complications, chemo-, and radiation therapy. Recently, new therapeutic approaches were considered globally for increasing conventional cancer therapy efficacy and decreasing the adverse effects. Bioactive peptides obtained from plant and animal sources have drawn increased attention because of their potential as complementary therapy. This review presents a contemporary examination of bioactive peptides derived from natural origins with demonstrated anticancer, ant invasion, and immunomodulation properties. For example, peptides derived from common beans, chickpeas, wheat germ, and mung beans exhibited antiproliferative and toxic effects on cancer cells, favoring cell cycle arrest and apoptosis. On the other hand, peptides from marine sources showed the potential for inhibiting tumor growth and metastasis. In this review we will discuss these data highlighting the potential befits of these approaches and the need of further investigations to fully characterize their potential in clinics.

The beneficial potential of protein hydrolysates as prebiotic for probiotics and its biological activity: a review

Probiotics are not only a food supplement, but they have shown great potential in their nutritional, health and therapeutic effects. To maximize the beneficial effects of probiotics, it is commonly achieved by adding prebiotics. Prebiotics primarily comprise indigestible carbohydrates, specific peptides, proteins, and lipids, with oligosaccharides being the most extensively studied prebiotics. However, these rapidly fermenting oligosaccharides have many drawbacks and can cause diarrhea and flatulence in the body. Hence, the exploration of new prebiotic is of great interest. Besides oligosaccharides, protein hydrolysates have been demonstrated to enhance the expression of beneficial properties of probiotics. Consequently, this paper outlines the mechanism underlying the action of protein hydrolysates on probiotics, as well as the advantageous impacts of proteins hydrolysates derived from various food sources on probiotics. In addition, this paper also reviews the currently reported biological activities of protein hydrolysates. The aim is a theoretical basis for the development and implementation of novel prebiotics.

Evening primrose oil: a comprehensive review of its bioactives, extraction, analysis, oil quality, therapeutic merits, and safety

Oil crops have become increasingly farmed worldwide because of their numerous functions in foods and health. In particular, oil derived from the seeds of evening primrose (Oenothera biennis) (EPO) comprises essential fatty acids of the omega-6 (ω-6) series. It is well recognized to promote immune cells with a healthy balance and management of female ailments. The nutrients of interest in this oil are linoleic acid (LA, 70-74%) and γ-linolenic acid (GLA, 8-10%), which are polyunsaturated fatty acids (PUFA) that account for EPO's popularity as a dietary supplement. Various other chemicals in EPO function together to supply the body with PUFA, elevate normal ω-6 essential fatty acid levels, and support general health and well-being. The inclusive EPO biochemical analysis further succeeded in identifying several other components, i.e., triterpenes, phenolic acids, tocopherols, and phytosterols of potential health benefits. This comprehensive review capitalizes on EPO, the superior product of O. biennis, highlighting the interrelationship between various methods of cultivation, extraction, holistic chemical composition, sensory characters, and medicinal value. Besides the literature review, this study restates the numerous health advantages of primrose oil and possible drug-EPO interactions since a wide spectrum of drugs are administered concomitantly with EPO. Modern techniques to evaluate EPO chemical composition are addressed with emphasis on the missing gaps and future perspectives to ensure best oil quality and nutraceutical benefits.

Nutritional and Nutraceutical Properties of Selected Pulses to Promote Gluten-Free Food Products

The market for gluten-free products is increasing with an estimated 7.6% annual growth rate from 2020 to 2027. It has been reported that most gluten-free products, such as bread, cookies, and pasta, contain great amounts of simple carbohydrates and are low in fiber and protein, affecting people's health. Pulses such as common beans, chickpeas, lentils, and peas have been studied as an alternative for developing gluten-free products because of their high protein and fiber content. In addition, they contain bioactive compounds with nutraceutical properties, such as phenolics, saponins, dietary fiber, and resistant starch, among others. Most studies carried out with pulses in vitro and in vivo have displayed health benefits, proving that pulse-based food products are better than their counterparts, even those containing wheat, with proper sensory acceptance. This work reviews pulse's nutritional and nutraceutical properties to promote the development and consumption of gluten-free products and improve their formulations to promote people's health.

Supplementation of quinoa peptides alleviates colorectal cancer and restores gut microbiota in AOM/DSS-treated mice

Quinoa protein hydrolysate has been previously reported to exert anti-cancer effects in cultured colon cancer cells. Here, we investigated the effect of quinoa protein and its hydrolysate on an azoxymethane/dextran sulfate sodium (AOM/DSS)-induced mouse model of colorectal cancer (CRC) and examined its underlying mechanism using gut microbiota analysis and short chain fatty acids (SCFAs) production analysis. Our results showed that quinoa protein or its hydrolysate mitigated the clinical symptoms of CRC and increased SCFAs contents in colon tissues. Moreover, administration of quinoa protein or its hydrolysate partially alleviated gut microbiota dysbiosis in CRC mice by decreasing the abundance of pathogenic bacteria and increasing the abundance of probiotics. Additionally, PICRUSt analysis revealed that the functional profile of gut microbiota in the quinoa protein treated groups was more similar to that of the control group. These findings indicated that the modulation of gut microbiota by quinoa protein diet intervention may ameliorate AOM/DSS-induced CRC.

Prediction and Evaluation of Bioactive Properties of Cowpea Protein Hydrolysates

Cowpea protein hydrolysates were prepared using thermolysin, alcalase, and trypsin and analysed for bioactive properties, and then, the release of bioactive peptides was investigated in silico. It was found that the degree of hydrolysis reached 48% after 24 h hydrolysis with alcalase. The hydrolysate prepared using alcalase showed higher ACE inhibitory (62%) and DPPH scavenging activity (19%). SDS-PAGE analysis revealed that vignin was the major protein in cowpea protein isolate. In silico analysis indicated the presence of potential bioactive peptides with potent bioactivity in the primary structure of proteins. The 3D structure of proteins was built, upon which bioactive peptides were mapped using their location in the primary structure. The secondary structure and solvent accessible surface around each bioactive peptide were then calculated. On this basis, the higher degree of hydrolysis and bioactive properties of cowpea protein hydrolysate prepared by alcalase were explained, and structural factors influencing the release of bioactive peptides were investigated.

Bioactive Peptides: Potential Impact on the Treatment of Gastrointestinal Cancers

We have reviewed the potential use of bioactive peptides in the treatment of gastrointestinal (GI) malignancies, which are a significant cause of morbidity and mortality globally. Conventional therapies, such as surgery, chemotherapy, and radiotherapy, are associated with numerous side effects that may lead to longterm complications. Bioactive peptides are short-chain amino acids that can be extracted from natural sources or synthesized, and they have various potential health benefits, including anti-inflammatory, anti-hypertensive, antioxidant, antimicrobial, and anti-cancer properties. Bioactive peptides can be acquired from animal or plant sources, and can be classified based on their function, such as ACE-inhibiting, antimicrobial, and electrolyte- regulating peptides. Recent studies have demonstrated the promising role of bioactive peptides in tumor suppression, especially when combined with conventional therapies. In this study, we have reviewed the beneficial properties of bioactive peptides and their role in suppressing tumor activity. The mechanisms of bioactive peptides in tumor suppression are discussed. We have further reviewed the findings of preclinical and clinical studies that have investigated the application of bioactive peptides in the treatment of GI cancers. This review highlights the potential use of bioactive peptides as a promising treatment method for GI malignancies to increase the quality of life of GI cancer patients.

A Concise Review on the Role of Natural and Synthetically Derived Peptides in Colorectal Cancer

Colorectal cancer being the second leading cause of cancer-associated deaths has become a significant health concern around the globe. Though there are various cancer treatment approaches, many of them show adverse effects and some compromise the health of cancer patients. Hence, significant efforts are being made for the evolution of a novel biological therapeutic approach with better efficacy and minimal side effects. Current research suggests that the application of peptides in colorectal cancer therapeutics holds the possibility of the emergence of an anticancer reagent. The primary beneficial factors of peptides are their comparatively rapid and easy process of synthesis and the enormous potential for chemical alterations that can be evaluated for designing novel peptides and enhancing the delivery capacity of peptides. Peptides might be utilized as agents with cytotoxic activities or as a carrier of a specific drug or as cytotoxic agents that can efficiently target the tumor cells. Further, peptides can also be used as a tool for diagnostic purposes. The recent analysis aims at developing peptides that have the potential to efficiently target the tumor moieties without harming the nearby normal cells. Additionally, decreasing the adverse effects, and unfolding the other therapeutic properties of potential peptides, are also the subject matter of in-depth analysis. This review provides a concise summary of the function of both natural and synthetically derived peptides in colorectal cancer therapeutics that are recently being evaluated and their potent applications in the clinical field.

Biological functions of peptides from legumes in gastrointestinal health. A review legume peptides with gastrointestinal protection

Extensively consumed worldwide, legumes such as beans, soybeans, chickpeas, and peas represent a great source of protein. Legume-derived proteins provide bioactive peptides, small sequences of amino acids produced by enzymatic hydrolysis, gastrointestinal digestion, fermentation, or germination. Recent studies showed diverse biological effects of these peptides as antioxidants, antihypertensives, anti-inflammatory, antimicrobial, antithrombotic, antidiabetic, hypocholesterolemic, and even immunomodulators. These beneficial effects aid in preventing and treating chronic illnesses, particularly inflammatory disorders, obesity, and cardiovascular diseases. Thus, this work discusses these biological functions in gastrointestinal digestion health of bioactive peptides obtained from common beans, soybeans, chickpeas, peas, and other legumes. PRACTICAL APPLICATIONS: Knowledge of the nutraceutical properties of legumes can encourage the use of these seeds as ingredients in the development and design of functional foods.

Immunostimulant plant proteins: Potential candidates as vaccine adjuvants

The COVID-19 pandemic is shaking up global scientific structures toward addressing antibiotic resistance threats and indicates an urgent need to develop more cost-effective vaccines. Vaccine adjuvants play a crucial role in boosting immunogenicity and improving vaccine efficacy. The toxicity and adversity of most adjuvant formulations are the major human immunization problems, especially in routine pediatric and immunocompromised patients. The present review focused on preclinical studies of immunoadjuvant plant proteins in use with antiparasitic, antifungal, and antiviral vaccines. Moreover, this report outlines the current perspective of immunostimulant plant protein candidates that can be used by researchers in developing new generations of vaccine-adjuvants. Future clinical studies are required to substantiate the plant proteins' safety and applicability as a vaccine adjuvant in pharmaceutical manufacturing.

Resistant Protein: Forms and Functions

Several global health risks are related to our dietary lifestyle. As a consequence of the overconsumption of ultra-processed and highly digestible protein (150–200% of the recommended value), excess dietary proteins reach the colon, are hydrolysed to peptides and amino acids by bacterial proteases and fermented to various potentially toxic end products. A diet reformulation strategy with reduced protein content in food products appears to be the most effective approach. A potential approach to this challenge is to reduce food digestibility by introducing resistant protein into the diet that could positively influence human health and gut microbiome functionality. Resistant protein is a dietary constituent not hydrolysed by digestive enzymes or absorbed in the human small intestine. The chemical conformation and the amino acid composition strictly influence its structural stability and resistance to in vivo proteolysis and denaturation. Responding to the important gap in our knowledge regarding the digestibility performance of alternative proteins, we hypothesise that resistant proteins can beneficially alter food functionality via their role in improving metabolic properties and health benefits in human nutrition, similar to fibres and resistant starches. A multidisciplinary investigation of resistant protein will generate tremendous scientific impact for other interlinked societal, economic, technological and health and wellbeing aspects of human life.

Preparation and identification of anti-breast cancer cells peptides released from yak milk casein

Yak milk casein (YMC) is the main protein in the yak milk. Peptides released from Yak milk casein (YMC) have multiple bioactivities, including anti-inflammation and immune-regulation, suggesting that these peptides might be able to inhibit cancer theoretically. However, the anti-cancer peptides from YMC have only been sparsely studied. Breast carcinoma is the most common carcinoma in women worldwide. Thus, the paper herein was to identify yak milk casein (YMC)-derived anti-breast cancer peptides via gel filtration, reversed phase high-performance liquid chromatography (RP-HPLC) and liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI MS/MS) for the first time. The inhibitory effects of the hydrolysates on the cell viabilities, cell cycles and apoptosis of breast cancer cells were evaluated with a cck8 kit and a flow cytometry. The result showed that YMC hydrolysates (YMCH) obtained by united hydrolyzation with trypsin (3 h) and alkaline protease (3 h) displayed the highest cell viability inhibition rate for MCF7 (20.74 ± 1.39%) and MDA-MB-231 (26.73 ± 2.87%) cells. Three peptides were identified in the RP-HPLC subfraction F3-4, and a nonapeptide (TPVVVPPFL) showed the most potent inhibitory effects on both cancer cells and displayed good gastrointestinal stability. TPVVVPPFL could induce G2-M cell cycle arrest in MCF7 cells and S cell arrest in MDA-MB-231 cells and induce apoptosis in both cancer cells. Moreover, in silico analysis indicated that the peptide had non-toxic and no inhibitory roles on P4502D6-enzyme. Together, this study shows that YMC is a good source of anti-breast cancer cells peptides.

Health Benefits of Cereal Grain- and Pulse-Derived Proteins

Pulses and whole grains are considered staple foods that provide a significant amount of calories, fibre and protein, making them key food sources in a nutritionally balanced diet. Additionally, pulses and whole grains contain many bioactive compounds such as dietary fibre, resistant starch, phenolic compounds and mono- and polyunsaturated fatty acids that are known to combat chronic disease. Notably, recent research has demonstrated that protein derived from pulse and whole grain sources contains bioactive peptides that also possess disease-fighting properties. Mechanisms of action include inhibition or alteration of enzyme activities, vasodilatation, modulation of lipid metabolism and gut microbiome and oxidative stress reduction. Consumer demand for plant-based proteins has skyrocketed primarily based on the perceived health benefits and lower carbon footprint of consuming foods from plant sources versus animal. Therefore, more research should be invested in discovering the health-promoting effects that pulse and whole grain proteins have to offer.

Bioactive peptides of plant origin: distribution, functionality, and evidence of benefits in food and health

The multiple functions of peptides released from proteins have immense potential in food and health. In the past few decades, research interest in bioactive peptides of plant origin has surged tremendously, and new plant-derived peptides are continually discovered with advances in extraction, purification, and characterization technology. Plant-derived peptides are mainly extracted from dicot plants possessing bioactive functions, including antioxidant, cholesterol-lowering, and antihypertensive activities. Although the distinct functions are said to depend on the composition and structure of amino acids, the practical or industrial application of plant-derived peptides with bioactive features is still a long way off. In summary, the present review mainly focuses on the state-of-the-art extraction, separation, and analytical techniques, functional properties, mechanism of action, and clinical study of plant-derived peptides. Special emphasis has been placed on the necessity of more pre-clinical and clinical trials to authenticate the health claims of plant-derived peptides.

Immunomodulatory peptides-A promising source for novel functional food production and drug discovery

Immunomodulatory peptides are a complex class of bioactive peptides that encompasses substances with different mechanisms of action. Immunomodulatory peptides could also be used in vaccines as adjuvants which would be extremely desirable, especially in response to pandemics. Thus, immunomodulatory peptides in food of plant origin could be regarded both as valuable suplements of novel functional food preparation and/or as precursors or possible active ingredients for drugs design for treatment variety of conditions arising from impaired function of immune system. Given variety of mechanisms, different tests are required to assess effects of immunomodulatory peptides. Some of those effects show good correlation with in vivo results but others, less so. Certain plant peptides, such as defensins, show both immunomodulatory and antimicrobial effect, which makes them interesting candidates for preparation of functional food and feed, as well as templates for design of synthetic peptides.

Manufacturing of Plant-Based Bioactive Peptides Using Enzymatic Methods to Meet Health and Sustainability Targets of the Sustainable Development Goals

Due to the rapid growth in the global population, the consumption of animal-based food products/food compounds has been associated with negative implications for food sustainability/security. As a result, there is an increasing demand for the development of plant-based food and compounds as alternatives. Meanwhile, a growing number of studies report the health benefits of food protein-based peptides prepared via enzymatic hydrolysis and exhibiting biological properties such as antioxidant, antihypertensive, anti-thrombotic, and antidiabetic activities. However, the inherent bitterness of some peptides hinders their application in food products as ingredients. This article aims to provide the latest findings on plant-based bioactive peptides, particularly their health benefits, manufacturing methods, detection and qualification of their bitterness properties, as well as debittering methods to reduce or eliminate this negative sensory characteristic. However, there is still a paucity of research on the biological property of debittered peptides. Therefore, the role of plant protein-derived bioactive peptides to meet the health targets of the Sustainable Development Goals can only be realised if advances are made in the industrial-scale bioprocessing and debittering of these peptides.

The Synthesis of Conjugated Peptides Containing Triazole and Quinolone-3-Carboxamide Moieties Designed as Anticancer Agents

Background

Cancer is a major health concern in human populations worldwide, and due to its causes being multi-factorial, it is not easily curable. Many attempts have been made to tackle this disease in hopes of finding effective anticancer agents which are not harmful to healthy tissues. Peptides with several medicinal activities have been shown to be good candidates as anticancer agents to replace common classic anticancer drugs. Peptides in conjugation with either biologically active heterocyclic compounds or anticancer drugs may result in new molecules compiling the biological benefits of both individual compounds within a unit structure.

Objective

In this study some triazole-peptide conjugates as well as ciprofloxacin-peptide conjugates were designed, synthesized, and their anticancer activities evaluated. A normal skin cell line, NIH3, was also employed to determine the safety profiles of these conjugates.

Materials and Methods

Two peptides; YIGSR and LSGNK were synthesized by the solid phase peptide synthesis (SPPS) method using Wang resin. Cell viability was examined by employing the MTT assay. To determine the cytotoxicity of the triazole and ciprofloxacin conjugates, two human cancer cell lines were employed; HepG2 (human liver cancer cell line) and LNCaP (human prostatic carcinoma cell line). A human skin fibroblast cell line was also included for comparison.

Results

MTT results showed that all the compounds could inhibit the viability of cancerous cells in a concentration- dependent manner.

Conclusions

The results showed that these peptide conjugates are toxic against the aforementioned cancerous cells and thus may raise a hope for finding new anticancer agents made by such strategy in the near future.

Research Development, Optimization and Modifications of Anti-cancer Peptides

Anti-cancer peptides play an important role in the area of cancer inhibition. A variety of anti- cancer peptides have emerged through the extraction and structural modification of peptides from biological tissues. This review provides the research background of anti-cancer peptides, the introduction of the mechanism of anti-cancer peptides for inhibition of cancers, the discovery and development along with optimization and modifications of these peptides in the clinical application. In conclusion, it can be said that anti-cancer peptides will play a major role in the future oncologic clinic.

Anticancer activity of protein fractions from chia (Salvia hispanica L.)

Salvia hispanica demonstrated to be a source of protein fractions with anticancer activity. The effect of the protein fractions <1, 1-3, and 3-5 kDa, obtained by ultrafiltration of the S. hispanica hydrolysate, was evaluated on the cellular viability of four cancer cell lines (MCF-7, Caco2, PC-3, and HepG2) and on human fibroblasts (hFB) at different concentrations (0.25, 0.5, 0.75, and 1 mg/ml). The protein fractions did not show cytotoxic effects on hFB. The protein fraction <1 kDa at 1 mg/ml showed the highest statistical effect on the cellular viability of all evaluated cancer lines; thus, its amino acid sequence was analyzed. From the multicriteria decision analysis of the peptide sequences obtained by mass spectrometry, the peptide KLKKNL with potential anticancer activity was selected. In conclusion, protein fractions could represent a therapeutic option for cancer treatment. However, further investigations are necessary to establish conclusive arguments. PRACTICAL APPLICATION: The work of this article is based on the background of the increasing potential of peptides for the treatment of chronic diseases. The results of this study present peptides of low molecular weight, obtained from chia seeds, as a potential adjuvant option for cancer treatment.

A Novel Peptide Derived from Ginger Induces Apoptosis through the Modulation of p53, BAX, and BCL2 Expression in Leukemic Cell Lines

Despite the efficacy of chemotherapy, the adverse effects of chemotherapeutic drugs are considered a limitation of leukemia treatment. Therefore, a chemotherapy drug with minimal side effects is currently needed. One interesting molecule for this purpose is a bioactive peptide isolated from plants since it has less toxicity to normal cells. In this study, we extracted protein from the Zingiber officinale rhizome and performed purification to acquire the peptide fraction with the highest cytotoxicity using ultrafiltration, reverse-phase chromatography, and off-gel fractionation to get the peptide fraction that contained the highest cytotoxicity. Finally, a novel antileukemic peptide, P2 (sequence: RALGWSCL), was identified from the highest cytotoxicity fraction. The P2 peptide reduced the cell viability of NB4, MOLT4, and Raji cell lines without an effect on the normal peripheral blood mononuclear cells. The combination of P2 and daunorubicin significantly decreased leukemic cell viability when compared to treatment with either P2 or daunorubicin alone. In addition, leukemic cells treated with P2 demonstrated increased apoptosis and upregulation of caspase 3, 8, and 9 gene expression. Moreover, we also examined the effects of P2 on p53, which is the key regulator of apoptosis. Our results showed that treatment of leukemic cells with P2 led to the upregulation of p53 and Bcl-2-associated X protein, and the downregulation of B-cell lymphoma 2, indicating that p53 is involved in apoptosis induction by P2. The results of this study are anticipated to be useful for the development of P2 as an alternative drug for the treatment of leukemia.

Oral delivery of self-assembling bioactive peptides to target gastrointestinal tract disease

Peptides are known for their diverse bioactivities including antioxidant, antimicrobial, and anticancer activity, all three of which are potentially useful in treating colon-associated diseases. Beside their capability to stimulate positive health effects once released in the body, peptides are able to form useful nanostructures such as hydrogels. Combining peptide bioactivity and peptide gel-forming potentials can create interesting systems that can be used for oral delivery. This combination, acting as a two-in-one system, has the potential to avoid the need for delicate entrapment of a drug or natural bioactive compound. We here review the context and research progress, to date, in this area.

Bioactive peptide isolated from sesame seeds inhibits cell proliferation and induces apoptosis and autophagy in leukemic cells

Leukemia is the most common type of hematological malignancies. Several natural products including bioactive peptides have been explored and studied for their anti-leukemic activities. In the present study, anti-leukemic peptide, IGTLILM (IM-7), was isolated and identified from the protein hydrolysate of sesame seeds by reverse phase-solid phase extraction, off-gel fractionation and nano LC-MS/MS. The cytotoxic effects of IM-7 were studied in MOLT-4 and NB4 acute leukemic cell lines using an MTT assay. The induction of apoptosis and autophagy was investigated by flow cytometry using Annexin V-FITC/PI staining and anti-LC3/FITC antibodies, respectively. The mRNA alterations of apoptotic and autophagic-related genes were determined by reverse transcription-quantitative PCR. The present study found that IM-7 inhibited the proliferation of MOLT-4 and NB4 cells in dose-dependent manner, but it showed a minimal effect on healthy mononuclear cells. IM-7 activated apoptosis and autophagy through the upregulation of CASP3, ULK1 and BECN1 and the downregulation of BCL2. In addition, IM-7 enhanced the cytotoxic effect of the anti-leukemic drug, daunorubicin. The findings suggested that IM-7 was potent to suppress the proliferation of MOLT-4 and NB4 leukemic cells and induce apoptosis and autophagy through the regulation of caspase 3-Bcl-2 and ULK1-Beclin1, respectively.

A novel peptide isolated from garlic shows anticancer effect against leukemic cell lines via interaction with Bcl-2 family proteins

Leukemia is a group of cancer caused by the abnormal proliferation and differentiation of hematopoietic stem cells. Efforts geared toward effective therapeutic strategies with minimal side effects are underway. Peptides derived from natural resources have recently gained special attention as alternative chemotherapeutic agents due to their minimal adverse effects. In the present study, the aim was to isolate peptides from garlic (Allium sativum) and investigate their anticancer activity against leukemic cell lines. The protein extract of A. sativum was pepsin-digested to obtain protein hydrolysate followed by sequential purification methods. A novel anticancer peptide, VKLRSLLCS (VS-9), was identified and characterized by mass spectrometric analysis. The peptide was demonstrated to significantly inhibit the cell proliferation of MOLT-4 and K562 leukemic cell lines while exhibiting minimal inhibition against normal PBMC. Particularly, VS-9 could induce apoptosis and upregulate mRNA levels of caspase 3, caspase 8, caspase 9, and Bax while downregulating Bcl-2, Bcl-xL, and Bcl-w. Molecular docking of VS-9 with the anti-apoptotic Bcl-2 protein family suggested that VS-9 could bind the binding groove of the BH3 domain on target proteins. Protein-peptide interaction analysis by affinity chromatography and LC-MS/MS further showed that VS-9 could bind Bcl-2 proteins. Results suggest VS-9 as a potential garlic-derived novel anticancer peptide possessing apoptosis-inducing properties against leukemic cell lines via anti-apoptotic Bcl-2 protein family.

Bioactive peptide of Cicer arietinum L. induces apoptosis in human endometrial cancer via DNA fragmentation and cell cycle arrest

Chickpea seed proteins are alleged source of nutraceuticals. These seed proteins were subjected to different proteases to produce peptides. The efficacy of these peptides was confirmed using six diverse human cancer cell lines (PA-1, Ishikawa cells, A549, MCF-7, HepG2, MDA-MB-231). Alcalase generated peptides exhibited the highest antagonistic inhibition of Ishikawa cells. Flow cytometric analysis revealed that chickpea peptide induced S and G2 phase arrest of cell cycle in a dose dependent manner. DNA fragmentation and apoptosis occurred by down regulation of Bcl-2 expression, upregulation of Bax expression and promotion of caspase-3 initiation. Chickpea peptides ascertain potential antiproliferative molecule that can be deployed in cancer treatment regimes.

Peptides in Colorectal Cancer: Current State of Knowledge

Colorectal cancer (CRC) is the second most deadly and the third most commonly diagnosed cancer in the world. CRC treatment is mainly based on surgery, chemotherapy, and even though the probability of complications after surgery is very low, chemo drugs affect the patient's quality of life. Multiple studies have shown a strong correlation between diet and the onset and progression of CRC. Thus, the consumption of dietary nutraceuticals for its treatment and prevention has been suggested as a promising option. Peptides have increasingly become of interest in human health due to their antioxidant, antihypertensive, and anticancer potential. In recent years, there have been extensive reports on peptides with anti-tumor activity, and some studies suggest that peptides modulate cell proliferation, evasion of cell death, and metastasis in malignant cells. Plant-derived peptides such as soybean, bean, and rice have received main attention. In this review, we show evidence of several mechanisms through which bioactive peptides exert anti-tumor activity over in vitro and in vivo CRC models. We also report the current status of major production techniques, as well as limitations and future perspectives. Graphical Abstract.

Immunomodulatory and Antioxidant Properties of Wheat Gluten Protein Hydrolysates in Human Peripheral Blood Mononuclear Cells

Peptides from several plant food proteins not only maintain the nutritional values of the original protein and decrease the environmental impact of animal agriculture, but also exert biological activities with significant health-beneficial effects. Wheat is the most important food grain source in the world. However, negative attention on wheat-based products has arose due to the role of gluten in celiac disease. A controlled enzymatic hydrolysis could reduce the antigenicity of wheat gluten protein hydrolysates (WGPHs). Therefore, the aims of the present study were to evaluate the effects of the in vitro administration of Alcalase-generated WGPHs on the immunological and antioxidant responses of human peripheral blood mononuclear cells (PBMCs) from 39 healthy subjects. WGPH treatment reduced cell proliferation and the production of the Type 1 T helper (Th1) and Th17 pro-inflammatory cytokines IFN-γ and IL-17, respectively. WPGHs also improved the cellular anti-inflammatory microenvironment, increasing Th2/Th1 and Th2/Th17 balances. Additionally, WGPHs improved global antioxidant capacity, increased levels of the reduced form of glutathione and reduced nitric oxide production. These findings, not previously reported, highlight the beneficial capacity of these vegetable protein hydrolysates, which might represent an effective alternative in functional food generation.

Bioactive peptides from beans with the potential to decrease the risk of developing noncommunicable chronic diseases

Several studies have demonstrated that peptides obtained from the proteins of different bean species have the potential to act on therapeutic targets of noncommunicable chronic diseases or NCDs. However, peptides with great structural diversity can be obtained from the hydrolysis of proteins present in foods. Therefore, the present review had the objective of identifying, in silico, the possibility of obtaining peptides with potential biological activity from the storage globulin proteins of the bean species Phaseolus vulgaris (L.), Vigna angularis (Willd.), Vigna radiata (L.) and Vigna unguiculata (L.) Walp., using the UniProtKB, BIOPEP and PeptideRanker databases, as well as reviewing available research reports that showed evidence bioactive properties of peptides obtained from beans via in vitro assays. For all the species studied, the highest frequency of the occurrence of bioactive fragments was found for the inhibition of dipeptidyl peptidase-IV, followed by the inhibition of the angiotensin-converting enzyme and by antioxidant activity. The inhibition of the two enzymes is the therapeutic target of drugs used for type 2 diabetes mellitus (T2DM) and for hypertension, respectively, while the antioxidant activity can prevent the development of several chronic diseases related to oxidative stress.

Legume Proteins as a Promising Source of Anti-Inflammatory Peptides

Legume proteins are precursors of bioactive components, such as peptides. In the present paper, different types of legume as sources of bioactive peptides and hydrolysates are considered and discussed based on their anti-inflammatory effect. Peptides with anti-inflammatory activity were included from in vitro and in vivo studies. Current strategies for obtaining bioactive peptides, as well as their structure and impact on health, were also reviewed. It was discovered that peptides derived from legume protein, mainly soybean and bean, can regulate several inflammatory markers, which include prostaglandin E2 (PGE2), nitric oxide (NO), inducible nitric oxide synthase (iNOS), cyclooxygenase 2 (COX- 2), cytokines, and chemokines. So far, lunasin, VPY and γ-glutamyl peptides have been identified with anti-inflammatory activity but their mechanisms have not been fully elucidated. Furthermore, it is necessary to gather more information about hydrolysates containing peptides and single peptides with antiinflammatory activity. Considering the wide diversity, legume may be promising components to produce peptides efficient to ameliorate inflammatory disorders.

Research Progress Evaluating the Function and Mechanism of Anti-Tumor Peptides

Malignant tumors cause a high mortality rate worldwide, and they severely threaten human health and negatively affect the economy. Despite the advancements in tumor-related molecular genetics and effective new processes in anti-tumor drug development, the anti-tumor drugs currently used in clinical practice are inadequate due to their poor efficacy or severe side effects. Therefore, developing new safe and efficient drugs is a top priority for curing cancer. The peptide has become a suitable agent due to its exact molecular weight between whole protein and small molecule, and it has high targeting ability, high penetrability, low immunogenicity, and is convenient to synthesize and easy to modify. Because of these advantages, peptides have excellent prospect for application as anti-tumor agents. This article reviews the recent research progress evaluating anti-tumor peptides and their anti-tumor mechanisms, and may act as a reference for the future development and clinical application of anti-tumor peptides.

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Protein Hydrolysates from Fenugreek (Trigonella foenum graecum) as Nutraceutical Molecules in Colon Cancer Treatment

The application of plant extracts for therapeutic purposes has been used in traditional medicine since the plants are a source of a great variety of chemical compounds that possess biological activity. Actually, the effect of these extracts on diseases such as cancer is being widely studied. Colorectal adenocarcinoma is one of the main causes of cancer related to death and the second most prevalent carcinoma in Western countries. The aim of this work is to study the possible effect of two fenugreek (Trigonella foenum graecum) protein hydrolysates on treatment and progression of colorectal cancer. Fenugreek proteins from seeds were hydrolysed by using two enzymes separately, which are named Purafect and Esperase, and were then tested on differentiated and undifferentiated human colonic adenocarcinoma Caco2/TC7 cells. Both hydrolysates did not affect the growth of differentiated cells, while they caused a decrease in undifferentiated cell proliferation by early apoptosis and cell cycle arrest in phase G1. This was triggered by a mitochondrial membrane permeabilization, cytochrome C release to cytoplasm, and caspase-3 activation. In addition, the hydrolysates of fenugreek proteins displayed antioxidant activity since they reduce the intracellular levels of ROS. These findings suggest that fenugreek protein hydrolysates could be used as nutraceutical molecules in colorectal cancer treatment.

An anticoagulant peptide from beta-casein: identification, structure and molecular mechanism

A bioactive peptide is identified from casein hydrolysates.

Design, Synthesis and Biological Evaluation of Ciprofloxacin- Peptide Conjugates as Anticancer Agents

Cancer has emerged as a leading cause of death throughout the world. Peptides are a novel class of anticancer agents that can specifically target cancer cells with low toxicity to normal tissues and thus, offer new opportunities for future cancer treatment. On the other hand, Ciprofloxacin, an antibiotic, also known to its anticancer property for enabling cell cycle arrest and creating double strand breaks in nucleic acid can trigger apoptosis of cancer cells. Thus, joining anticancer peptides with Ciprofloxacin may be good idea to get benefit of the both compounds' properties and therefore gives better anticancer agents. The aim of this study was to synthesize Ciprofloxacin- cytotoxic peptide conjugates and to investigate the anticancer activity of the resultant compounds. The conjugates were prepared by solid phase peptide synthesis technique using Fmoc strategy. Anticancer activity of these compounds was examined on three cancer cell lines, HT-29, MCF-7, MDA-MB-231 as well as skin fibroblast cells as a control, employing MTT test. Our results showed that the cytotoxic activity of the synthesized compounds against cancer cells was raised considerably without producing a high toxicity on normal cells. Moreover, Ciprofloxacin-peptide conjugates showed selectivity against different kinds of breast cancer cells, especially on those with triple negative receptors. Therefore, it can be suggested that the strategy of making Ciprofloxacin- peptide conjugates as cytotoxic agents with safety profiles on the normal cells, rise promise to find better chemotherapeutic candidates to combat cancer.

Anti-proliferative Effect of a Novel Anti-oxidative Peptide in Hanwoo Beef on Human Colorectal Carcinoma Cells

The present study aimed to characterise anti-oxidant peptides from water-soluble protein extracts of Hanwoo beef and evaluate their anti-proliferative effect on human colorectal carcinoma cells (HCT116). Antioxidant peptides were purified from the low-molecular-weight fraction (<3 kDa) of Hanwoo beef extract. Antioxidant activity of peptide fractions was determined using the oxygen radical absorbance capacity (ORAC) assay. Purified peptide (P3) displayed higher ORAC activity than the low-molecular-weight fraction (202.66 μM TE/g vs 167.38 μM TE/g of dry matter, respectively) (p<0.05). The peptide sequence of P3 was Cys-Cys-Cys-Cys-Ser-Val-Gln-Lys (888.30 Da). The novel peptide P3, at 250 μg/mL, also significantly inhibited HCT116 cell proliferation up to 25.24% through phosphorylation of ERK, JNK, and p38 kinase (p<0.05). Hence, antioxidant peptide P3 from Hanwoo beef extract can be used as an antioxidative and anti-cancer agent in the functional food industry.

Risk of Colorectal Polyps and Malignancies Among Predominantly Rural Hispanics

Colorectal cancer is the fourth most frequently diagnosed cancer. However, due to variations in diet, it was hypothesized that risk of adenomatous or hyperplastic polyps or malignancies would be lower among Hispanics. Participants (n = 1671) underwent a colonoscopy. Results were grouped into one of four groups: normal, hyperplastic polyps only, adenomatous polyps, and malignancies. As expected, Hispanics had a lower risk of hyperplastic (p = .031, OR = 0.47) and adenomatous polyps (p = .031, OR = 0.66) than non-Hispanic Whites. Comparison between malignancies was not possible as no Hispanics had a malignancy. Contrary to expectations, risk of hyperplastic and adenomatous polyps and malignancies were no different between non-Hispanic Blacks and Whites. Among rural and mostly rural populations, Hispanics had a lower risk of hyperplastic and adenomatous polyps.

Inhibitory Effects of Pulse Bioactive Compounds on Cancer Development Pathways

Previous studies suggest that pulses may have the potential to protect against cancer development by inhibiting pathways that result in the development of cancer. These pathways include those that result in inflammation, DNA damage, cell proliferation, and metastasis. Other studies have demonstrated extracts from pulses have the capacity to induce apoptosis specifically in cancer cells. Compounds reported to be responsible for these activities have included phenolic compounds, proteins and short chain fatty acids. The majority of the studies have been undertaken using in vitro cell culture models, however, there are a small number of in vivo studies that support the hypothesis that pulse consumption may inhibit cancer development. This review highlights the potential benefit of a diet rich in pulse bioactive compounds by exploring the anti-cancer properties of its polyphenols, proteins and short chain fatty acids.