Scientific Evidence of Rice By-Products for Cancer Prevention: Chemopreventive Properties of Waste Products from Rice Milling on Carcinogenesis In Vitro and In Vivo

Comparative Chemical Characterization of Potato Powders Using 1H NMR Spectroscopy and Chemometrics

This study presents the metabolic profiling of potato powders obtained through various processing procedures and commercially available potato powders. The metabolic fingerprinting was conducted using 1H NMR-based metabolomics coupled with machine learning projections. The results indicate hot air-dried potatoes have higher fumarate, glucose, malate, asparagine, choline, gamma aminobutyric acid (GABA), alanine, lactate, threonine, and fatty acids. In comparison, steam-cooked potatoes have higher levels of phenylalanine, sucrose, proline, citrate, glutamate, and valine. Moreover, the contents of metabolites in processed potatoes in this study were higher than those found in commercial potato powders, regardless of the drying or cooking methods used. The results indicate that a new processing technique may be developed to improve the nutritional value of potatoes.

Rice Bran: From Waste to Nutritious Food Ingredients

Rice (Oryza sativa L.) is a principal food for more than half of the world's people. Rice is predominantly consumed as white rice, a refined grain that is produced during the rice milling process which removes the bran and germ and leaves the starchy endosperm. Rice bran is a by-product produced from the rice milling process, which contains many bioactive compounds, for instance, phenolic compounds, tocotrienols, tocopherols, and γ-oryzanol. These bioactive compounds are thought to protect against cancer, vascular disease, and type 2 diabetes. Extraction of rice bran oil also generates various by-products including rice bran wax, defatted rice bran, filtered cake, and rice acid oil, and some of them exert bioactive substances that could be utilized as functional food ingredients. However, rice bran is often utilized as animal feed or discarded as waste. Therefore, this review aimed to discuss the role of rice bran in metabolic ailments. The bioactive constituents and food product application of rice bran were also highlighted in this study. Collectively, a better understanding of the underlying molecular mechanism and the role of these bioactive compounds exerted in the rice bran would provide a useful approach for the food industry and prevent metabolic ailments.

Evaluating the efficacy and feasibility of post harvest methods for arsenic removal from rice grain and reduction of arsenic induced cancer risk from rice-based diet

Food-chain arsenic (As) contamination is a severe environmental and health problem worldwide, and its intake through rice affects billions of people. In this review, we have summarized the post harvest As removal methods from rice and their efficacy and feasibility. Rice grain subspecies (indica and japonica), size (short, medium and long), type (husked, parboiled or polished), soaking time, temperature and rice to water ratio (r/w) during washing and cooking are the major factors that affect the removal of total arsenic (tAs) from rice grain. The reduction in tAs was greater in japonica than indica rice and was directly proportional to As in husked rice. For the removal of As, a low water volume (1:2 r/w) was more effective during washing due to friction between rice grains, while high water (≥4 times water) during cooking was more effective. Up to 80 % As was removed by cooking in 1:10 (rice: water). Soaking rice in edible acids such as vinegar, acetic and ascorbic acid was not effective, except citric acid, which removes tAs up to 63 %. Human-health risk assessment showed that these post harvest and cooking methods reduce the non-carcinogenic and incremental lifetime cancer risk by up to 5-fold, as calculated on the basis of bioaccessible inorganic As. These post harvest methods also remove nutrient elements and vitamins. The recommended dietary intake (RDI) of Zn and Cu was particularly affected (up to 40 and 83 %). The levels of P, Mo, Mn and Co were still sufficient to meet the RDI through the rice-based diet, while rice is already poor in the RDI of Ca, K, Fe and Se, and their levels were further reduced by 0.22-44 %. In conclusion, these post harvest and cooking methods may significantly reduce As induced health risks; however, other dietary sources of nutrients need to be carefully evaluated and supplemented.

Benefit of Asian pigmented rice bioactive compound and its implication in breast cancer: a systematic review

Background: Utilizing the bioactive compounds found in pigmented rice might significantly reduce the risk of breast cancer. This study aims to systematically review existing literature on the benefit of Asian pigmented rice bioactive compounds and their implication in breast cancer. Methods: Searches of the literature were conducted in two databases (Scopus and PubMed) for a systematic review. The keywords resulted in a total of 407 articles, consisting of 103 PubMed and 304 Scopus articles. 32 manuscripts were excluded because the article was over 10 years old. After excluding book chapters and non-English languages, we had 278 potential articles to be reviewed. After checking and screening the title and abstract and eliminating duplicate articles, then 66 articles were obtained. After the selection and elimination of the full-text manuscripts, finally 10 of them which met the inclusion criteria. Result: The included studies in this review were entirely based in Asia. The year of publication ranged from 2013 to 2020. Half of included studies used black rice extract, two used red jasmine rice extracts, and three used Korean rice extracts (black, red, dark purple and brown rice). All studies were conducted in vitro and three studies were compared with in vivo tests on female mice. The pigmented rice is mainly black, red, and dark purple rice, and contains a variety of peonidin-3-glucoside, cyanidin-3-glucoside, γ-oryzanol, γ-tocotrienol, proanthocyanidin, cinnamic acid, and anthocyanins that may act as pro-apoptotic, anti-proliferative, and anti-metastasis of the breast cancer cells. Conclusion: Pigmented rice is a beneficial food which possessed bioactive compounds that may have significant potential concerning a breast cancer.

The critical role of the phytosterols in modulating tumor microenvironment via multiple signaling: A comprehensive molecular approach

Cancer is the leading cause of mortality and morbidity worldwide, and its cases are rapidly increasing every year. Several factors contribute to the development of tumorigenesis. including radiation, dietary lifestyle, smoking, environmental, and genetic factors. The cell cycle is regulated by a variety of molecular signaling proteins. However, when the proteins involved in the cell cycle regulation are altered, cellular growth and proliferation are significantly affected. Natural products provide an important source of new drug development for a variety of ailments. including cancer. Phytosterols (PSs) are an important class of natural compounds reported for numerous pharmacological activities, including cancer. Various PSs, such as ergosterol, stigmasterol, sitosterol, withaferin A, etc., have been reported for their anti-cancer activities against a variety of cancer by modulating the tumor microenvironment via molecular signaling pathways discussed within the article. These signaling pathways are associated with the production of pro-inflammatory mediators, growth factors, chemokines, and pro-apoptotic and anti-apoptotic genes. These mediators and their upstream signaling are very active within the variety of tumors and by modulating these signalings, thus PS exhibits promising anti-cancer activities. However, further high-quality studies are needed to firmly establish the clinical efficacy as well the safety of the phytosterols.

Apoptosis in megakaryocytes: Safeguard and threat for thrombopoiesis

Platelets, generated from precursor megakaryocytes (MKs), are central mediators of hemostasis and thrombosis. The process of thrombopoiesis is extremely complex, regulated by multiple factors, and related to many cellular events including apoptosis. However, the role of apoptosis in thrombopoiesis has been controversial for many years. Some researchers believe that apoptosis is an ally of thrombopoiesis and platelets production is apoptosis-dependent, while others have suggested that apoptosis is dispensable for thrombopoiesis, and is even inhibited during this process. In this review, we will focus on this conflict, discuss the relationship between megakaryocytopoiesis, thrombopoiesis and apoptosis. In addition, we also consider why such a vast number of studies draw opposite conclusions of the role of apoptosis in thrombopoiesis, and try to figure out the truth behind the mystery. This review provides more comprehensive insights into the relationship between megakaryocytopoiesis, thrombopoiesis, and apoptosis and finds some clues for the possible pathological mechanisms of platelet disorders caused by abnormal apoptosis.

Inhibitory Effect of Dietary Defatted Rice Bran in an AOM/DSS-Induced Colitis-Associated Colorectal Cancer Experimental Animal Model

Defatted rice bran (DRB) is gaining immense popularity worldwide because of its nutritional and functional aspects. Emerging evidence suggests that DRB is a potential source of dietary fiber and phenolic compounds with numerous purported health benefits. However, less is known about its chemoprotective efficacy. In the present study, we determined and examined the nutrient composition of DRB and its chemopreventive effect on azoxymethane and dextran sulphate sodium (AOM/DSS)-induced colitis-associated colorectal cancer (CRC) in rats. The results showed the presence of several bioactive compounds, such as dietary fiber, phytic acid, and phenolic acids, in DRB. In addition, DRB supplementation reduced the progression of CRC symptoms, such as colonic shortening, disease activity index (DAI), and histopathological changes. Interestingly, a significant decrease was observed in total numbers of aberrant crypt foci (ACFs) and tumors with DRB supplementation. Furthermore, DRB supplementation suppressed the expression of pro-inflammatory cytokines (IL-6) and inflammatory mediators (NF-κB and COX-2) through the inactivation of the NF-κB signaling pathway. The administration of DRB revealed a negative effect on cancer cell proliferation by repressing the expression of nuclear β-catenin, cyclin D1, and c-Myc. These findings suggest that DRB supplementation mitigates chronic inflammation and cancer cell proliferation and delays tumorigenesis in rat AOM/DSS-induced colitis-associated CRC. Therefore, the establishment of DRB as a natural dietary food-derived chemopreventive agent has the potential to have a significant impact on cancer prevention in the global population.

Gender-based effect of absence of gut microbiota on the protective efficacy of Bifidobacterium longum-fermented rice bran diet against inflammation-associated colon tumorigenesis

Dietary rice bran (RB) has shown capacity to influence metabolism by modulation of gut microbiota in individuals at risk for colorectal cancer (CRC), which warranted attention for delineating mechanisms for bidirectional influences and cross-feeding between the host and RB-modified gut microbiota to reduce CRC. Accordingly, in the present study, fermented rice bran (FRB, fermented with a RB responsive microbe Bifidobacterium longum), and non-fermented RB were fed as 10% w/w (diet) to gut microbiota-intactspf or germ-free micegf to investigate comparative efficacy against inflammation-associated azoxymethane/dextran sodium sulfate (AOM/DSS)-induced CRC. Results indicated both microbiota-dependent and independent mechanisms for RB meditated protective efficacy against CRC that was associated with reduced neoplastic lesion size and local-mucosal/systemic inflammation, and restoration of colonic epithelial integrity. Enrichment of beneficial commensals (such as, Clostridiales, Blautia, Roseburia), phenolic metabolites (benzoate and catechol metabolism), and dietary components (ferulic acid-4 sulfate, trigonelline, and salicylate) were correlated with anti-CRC efficacy. Germ-free studies revealed gender-specific physiological variables could differentially impact CRC growth and progression. In the germ-free females, the RB dietary treatment showed a ∼72% reduction in the incidence of colonic epithelial erosion when compared to the ∼40% reduction in FRB-fed micegf . Ex vivo fermentation of RB did not parallel the localized-protective benefits of gut microbial metabolism by RB in damaged colonic tissues. Findings from this study suggest potential needs for safety considerations of fermented fiber rich foods as dietary strategies against severe inflammation-associated colon tumorigenesis (particularly with severe damage to the colonic epithelium).

The interaction between glycemic index, glycemic load, and the genetic variant ADIPOQ T45G (rs2241766) in the risk of colorectal cancer: a case-control study in a Korean population

PURPOSE

The glycemic index (GI), glycemic load (GL), and adiponectin level contribute to glycemic response and insulin sensitivity in the body. Studies have shown that tumor development is related to glycemic disorders; however, the results are contradictory. We aimed to investigate the association of GI and GL with colorectal cancer (CRC) risk in a Korean population and their possible interactions with the genetic variant ADIPOQ T45G.

METHODS AND RESULTS

A case-control study including 2096 participants with 695 CRC cases was conducted. The results showed that diets with high GI or GL were significantly associated with an increased risk of CRC [odds ratio (OR) = 5.44, 95% confidence interval (CI) 3.85-7.68; OR = 4.43, 95% CI 3.18-6.15, respectively; all p-trends < 0.001]. Moreover, even with a low-GI and low-GL diet, G/G genotype carriers may have 2.93-fold and 3.77-fold higher risk of rectal cancer compared to carriers of other genotypes (T/T + T/G), (OR = 2.93, 95% CI 1.01-8.59, p-interaction = 0.011 for GI; OR = 3.77, 95% CI 1.46-9.77, p-interaction = 0.025 for GL).

CONCLUSIONS

Overall, our study suggests positive associations of GI and GL with CRC risk. Moreover, the associations of GI and GL with rectal cancer risk could be modified by ADIPOQ T45G in a Korean population. Further studies with larger sample sizes are needed to confirm our findings.

Randomized, double-blind, placebo-controlled clinical trial measuring the effect of a dietetic food on dermatologic scoring and pruritus in dogs with atopic dermatitis

Background

Canine atopic dermatitis (AD) is a common condition that often requires multimodal therapy. Including a diet in the multimodal management of AD may reduce medication doses, saving pet owners money and reducing side effects. The objective of this randomized, double-blind, placebo-controlled clinical trial was to determine if a diet fortified in antioxidants, polyphenols, and omega-3 fatty acids can reduce the clinical signs of AD. Forty client-owned dogs with AD were enrolled in the study and assigned to either an enriched diet (diet B) or control diet (diet A) for 60-days. CADESI-4 index scores and owner-reported pruritus scores were measured periodically.

Results

Total CADESI-4 index scores for dogs eating diet B were lower on day 60 compared to baseline (P = 0.003). There was no statistical difference in scores for dogs eating diet A over a 60-day period. Diet B dogs had 25 and 49% reductions in CADESI-4 index scores on days 30 and 60, respectively (P = 0.0007) while diet A had no change over the study period. When comparing the percent change in owner-reported pruritus scores, diet B also performed better than diet A. By day 60, owners feeding diet B to their dogs reported a significant reduction (P < 0.0001) of 46.4% in itching, while those on diet A reported a 26.8% reduction, which was not statistically significant (P = 0.08).

Conclusions

These study results demonstrate feeding a diet enriched with ingredients to improve skin health and reduce inflammation improves the clinical signs of AD in dogs.

An Overview of Abiotic Stress in Cereal Crops: Negative Impacts, Regulation, Biotechnology and Integrated Omics

Abiotic stresses (AbS), such as drought, salinity, and thermal stresses, could highly affect the growth and development of plants. For decades, researchers have attempted to unravel the mechanisms of AbS for enhancing the corresponding tolerance of plants, especially for crop production in agriculture. In the present communication, we summarized the significant factors (atmosphere, soil and water) of AbS, their regulations, and integrated omics in the most important cereal crops in the world, especially rice, wheat, sorghum, and maize. It has been suggested that using systems biology and advanced sequencing approaches in genomics could help solve the AbS response in cereals. An emphasis was given to holistic approaches such as, bioinformatics and functional omics, gene mining and agronomic traits, genome-wide association studies (GWAS), and transcription factors (TFs) family with respect to AbS. In addition, the development of omics studies has improved to address the identification of AbS responsive genes and it enables the interaction between signaling pathways, molecular insights, novel traits and their significance in cereal crops. This review compares AbS mechanisms to omics and bioinformatics resources to provide a comprehensive view of the mechanisms. Moreover, further studies are needed to obtain the information from the integrated omics databases to understand the AbS mechanisms for the development of large spectrum AbS-tolerant crop production.

Effects of a Rice Bran Dietary Intervention on the Composition of the Intestinal Microbiota of Adults with a High Risk of Colorectal Cancer: A Pilot Randomised-Controlled Trial

Rice bran exhibits chemopreventive properties that may help to prevent colorectal cancer (CRC), and a short-term rice bran dietary intervention may promote intestinal health via modification of the intestinal microbiota. We conducted a pilot, double-blind, randomised placebo-controlled trial to assess the feasibility of implementing a long-term (24-week) rice bran dietary intervention in Chinese subjects with a high risk of CRC, and to examine its effects on the composition of their intestinal microbiota. Forty subjects were randomised into the intervention group (n = 19) or the control group (n = 20). The intervention participants consumed 30 g of rice bran over 24-h intervals for 24 weeks, whilst the control participants consumed 30 g of rice powder on the same schedule. High rates of retention (97.5%) and compliance (≥91.3%) were observed. No adverse effects were reported. The intervention significantly enhanced the intestinal abundance of Firmicutes and Lactobacillus, and tended to increase the Firmicutes/Bacteroidetes ratio and the intestinal abundance of Prevotella_9 and the health-promoting Lactobacillales and Bifidobacteria, but had no effect on bacterial diversity. Overall, a 24-week rice bran dietary intervention was feasible, and may increase intestinal health by inducing health-promoting modification of the intestinal microbiota. Further larger-scale studies involving a longer intervention duration and multiple follow-up outcome assessments are recommended.

Inhibitory Effect of Thai Purple Rice Husk Extract on Chemically Induced Carcinogenesis in Rats

This study investigated the cancer chemopreventive effects of an acidic methanol extract of purple rice husk on chemically induced carcinogenesis in rats. This purple rice husk extract (PRHE) had high polyphenol contents. Vanillic acid was a major phenolic compound in PRHE. Three major anthocyanins found in PRHE were malvidin-3-glucoside, peonidin-3-glucoside and cyanidin-3-glucoside. PRHE was not toxic and clastogenic in rats. The LD50 of PRHE was greater than 2000 mg kg-1 body weight (BW). The oral administration of 300 or 1000 mg kg-1 BW of PRHE for 28 days significantly decreased the number of micronucleated hepatocytes in diethylnitrosamine-initiated rats. The inhibitory mechanisms were associated with the reduction of cytochrome P450 2E1 expression and induction of some detoxifying enzymes in the liver. In addition, treatment with 500 mg kg-1 BW of PRHE for eight weeks did not induce preneoplastic lesions in the liver and colon. It significantly inhibited hepatic glutathione-S-transferase positive foci formation induced by diethylnitrosamine and 1,2-dimethylhydrazine by suppression of hepatocyte proliferation and induction of apoptosis. In conclusion, PRHE did not present toxicity, clastogenicity or carcinogenicity in rats. It exhibited cancer chemopreventive properties against chemically induced early stages rat hepatocarcinogenesis. Anthocyanins and vanillic acid might be candidate anticarcinogenic compounds in purple rice husk.

Inhibition of HIV-1 Protease by Carpobrotus edulis (L.)

Carpobrotus edulis (L.) is a plant commonly found in the Eastern Cape Province of South Africa and is used for the general treatment of infections relating to the human immunodeficiency virus (HIV). HIV-1 protease plays an important role during HIV replication and maturation to its infectious form, and therefore inhibition of the enzyme is one of the main focus areas in drug development. The inhibitory effect of a water extract of C. edulis leaves against HIV-1 protease activity was determined using the SensoLyte® 520 HIV-1 protease assay fluorimetric kit and employing a HiLyte Fluor™488/QXL™520 fluorescence resonance energy transfer (FRET) peptide. Cytotoxicity of the extract towards HeLa Chang cell lines was determined using an in vitro MTT assay, and the phytochemical profile of the extract was determined with FT-IR and LC-MS. HIV-1 protease activity was inhibited 83.06% (IC₅₀ 1.6 mg/ml) (p < 0.0001) by the pepstatin A inhibitor control. Treatment with all C. edulis extract concentrations (16, 1.6, 0.16, and 0.016 mg/ml) inhibited HIV-1 protease activity significantly (p < 0.0001) in a typical dose response manner. With regards to cytotoxicity, the negative controls containing untreated HeLa Chang cells exhibited high formazan formation rates in contrast with the positive controls, containing curcumin, which reduced formazan formation significantly (p < 0.001), exhibiting cytotoxicity towards the cells. There was no significant (p > 0.05) difference in the formazan formation rates between the negative controls and 1, 0.5, 0.125, 0.065, 0.031, and 0.015 mg/ml plant extract, confirming no toxicity of C. edulis extracts towards HeLa Chang cells. Major functional phytochemical compounds identified included alcohols, phenols, alkanes, amines, carboxylic acids, and esters. LC-ESI-TOF/MS analysis revealed the putative identities of main compounds present in the aqueous leaves extract, including some that contribute to its anti-HIV-1 protease action.

Dietary Mixed Cereal Grains Ameliorate the Azoxymethane and Dextran Sodium Sulfate-Induced Colonic Carcinogenesis in C57BL/6J Mice

The chemopreventive effects of various mixed cereal grain (MCG) samples on azoxymethane (AOM, 10 mg/kg) and dextran sulfate sodium (DSS, 0.02 g/mL)-induced colorectal cancer (CRC) in C57BL/6J mice were studied. The main MCG preparation consisted of fermented brown rice (FBR), glutinous brown rice, glutinous Sorghum bicolor, glutinous Panicum miliaceum, Coix lacryma-jobi, and black soybean at an appropriate mixing ratio. Other MCG preparations contained rice coated with 5% Phellinus linteus and 5% Curcuma longa (MCG-PC) or 10% Phellinus linteus (MCG-P) or 10% Curcuma longa (MCG-C). Consumption of dietary MCG-PC by CRC mice significantly increased colon length, decreased the ratio of colon weight to length, and reduced the number of colon tumors. Similar effects, although to a lower extent, were observed in CRC mice fed with MCG-P, followed by those fed with MCG-C, MCG, FBR, or white rice. MCG-PC significantly suppressed colonic neoplasia and decreased the levels of various cytokines (tumor necrosis factor: Tnf, interleukin 1 beta: Il1b, interleukin 6: Il6, and interferon gamma: Ifnγ) in serum and colon tissue of the CRC mice. In addition, MCG-PC increased the mRNA expressions of tumor suppressor protein p53 (Tp53) and cyclin-dependent kinase inhibitor 1A (Cdkn1a), activated pro-apoptotic caspase 3 (Casp3), and reduced expressions of both mRNA and protein of inducible nitric oxide synthase 2 (Nos2), prostaglandin-endoperoxide synthase 2 (Ptgs2), and cyclin D1 (Ccnd1) in colon tissue. These findings suggest that compared with other cereal grain preparations, MCG-PC had a greater activity against AOM/DSS-induced CRC by reducing intestinal inflammation and modulating the expression of certain carcinogenesis related factors (Nos2, Ptgs2, Tp53, Cdkn1a, Ccnd1, and Casp3) in colon tissue of CRC mice.

Hexane Insoluble Fraction from Purple Rice Extract Retards Carcinogenesis and Castration-Resistant Cancer Growth of Prostate Through Suppression of Androgen Receptor Mediated Cell Proliferation and Metabolism

Prostate cancer and castration-resistant prostate cancer (CRPC) remain major health challenges in men. In this study, the inhibitory effects of a hexane insoluble fraction from a purple rice ethanolic extract (PRE-HIF) on prostate carcinogenesis and CRPC were investigated both in vivo and in vitro. In the Transgenic Rat for Adenocarcinoma of Prostate (TRAP) model, 1% PRE-HIF mixed diet-fed rats showed a significantly higher percentage of low-grade prostatic intraepithelial neoplasia and obvious reduction in the incidence of adenocarcinoma in the lateral lobes of the prostate. Additionally, 1% PRE-HIF supplied diet significantly suppressed the tumor growth in a rat CRPC xenograft model of PCai1 cells. In LNCaP and PCai1 cells, PRE-HIF treatment suppressed cell proliferation and induced G0/G1 cell-cycle arrest. Furthermore, androgen receptor (AR), cyclin D1, cdk4, and fatty acid synthase expression were down-regulated while attenuation of p38 mitogen-activated protein kinase, and AMP-activated protein kinase α activation occurred in PRE-HIF treated prostate cancer cells, rat prostate tissues, and CRPC tumors. Due to consistent results with PRE-HIF in PCai1 cells, cyanidin-3-glucoside was characterized as the active compound. Altogether, we surmise that PRE-HIF blocks the development of prostate cancer and CRPC through the inhibition of cell proliferation and metabolic pathways.

Efficacy of N-Methyl-N-Nitrosourea Mutation on Physicochemical Properties, Phytochemicals, and Momilactones A and B in Rice

Attempts regarding the improvement and development of novel rice with better quality and higher productivity have been increasing. Among approaches, mutation is a direct alteration on the genome and considered as one of the most beneficial routes to acquire new beneficial traits in rice. An experiment was carried out to explore the effects of N-methyl-N-nitrosourea (MNU) mutation on the antioxidant activities, phytochemical compounds, and momilactones A (MA) and B (MB) in rice. Two rice cultivars, K1 (an original cultivar DT84) and K2 (mutated DT84), were examined. Antioxidant activities, phenolic compounds, and momilactones of the rice grain, husk, and straw portions were measured and quantified. Antioxidant activities were higher in grain and straw of K2, whereas K1 showed greater antioxidant activity in rice husk. Additionally, K2 displayed higher total phenolic contents (TPC) in grain and straw as well as lower of it in the husk, but these variations significantly differed only in the straw portion. An increase in total flavonoid contents (TFC) was observed in the husk of K1, while K2 significantly enhanced TFC in straw. Both MA and MB, two compounds obtaining antidiabetes, anticancer, antimicrobial, antigout, and antiobesity properties, were detected and quantified in grain, husk, and straw of K1 and K2 samples. Generally, the contents of MA were higher than MB in all tested portions of rice crop. MA and MB were higher in straw followed by those in husk and grain, respectively. K2 contained higher amounts of MA and MB in straw and husk, but lower contents in grain compared with those in K1. This study illustrates that MNU mutation can improve grain quality and enhance bioactive compounds in straw, husk, and grain of rice. This approach has the potential to develop functional foods from rice, and therefore help farmers in developing countries to improve value in rice production.

Redox Homeostasis and Natural Dietary Compounds: Focusing on Antioxidants of Rice (Oryza sativa L.)

Redox homeostasis may be defined as the dynamic equilibrium between electrophiles and nucleophiles to maintain the optimum redox steady state. This mechanism involves complex reactions, including nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, activated by oxidative stress in order to restore the redox balance. The ability to maintain the optimal redox homeostasis is fundamental for preserving physiological functions and preventing phenotypic shift toward pathological conditions. Here, we reviewed mechanisms involved in redox homeostasis and how certain natural compounds regulate the nucleophilic tone. In addition, we focused on the antioxidant properties of rice and particularly on its bioactive compound, γ-oryzanol. It is well known that γ-oryzanol exerts a variety of beneficial effects mediated by its antioxidant properties. Recently, γ-oryzanol was also found as a Nrf2 inducer, resulting in nucleophilic tone regulation and making rice a para-hormetic food.

Antioxidant and Oxidative Stress: A Mutual Interplay in Age-Related Diseases

Aging is the progressive loss of organ and tissue function over time. Growing older is positively linked to cognitive and biological degeneration such as physical frailty, psychological impairment, and cognitive decline. Oxidative stress is considered as an imbalance between pro- and antioxidant species, which results in molecular and cellular damage. Oxidative stress plays a crucial role in the development of age-related diseases. Emerging research evidence has suggested that antioxidant can control the autoxidation by interrupting the propagation of free radicals or by inhibiting the formation of free radicals and subsequently reduce oxidative stress, improve immune function, and increase healthy longevity. Indeed, oxidation damage is highly dependent on the inherited or acquired defects in enzymes involved in the redox-mediated signaling pathways. Therefore, the role of molecules with antioxidant activity that promote healthy aging and counteract oxidative stress is worth to discuss further. Of particular interest in this article, we highlighted the molecular mechanisms of antioxidants involved in the prevention of age-related diseases. Taken together, a better understanding of the role of antioxidants involved in redox modulation of inflammation would provide a useful approach for potential interventions, and subsequently promoting healthy longevity.

Chemopreventive Potential of Cereal Polyphenols

It has been identified that diet is one of the major contributing factors associated with the development of cancer and other chronic pathologies. In the recent years, supplementing regular diet with food and/or its components that contain chemopreventive properties has been considered an effective approach in reducing the incidence of cancer and other lifestyle associated diseases. This systematic review provides an exhaustive summary of the chemopreventive properties exhibited by everyday dietary ingredients such as rice, barley, oats, and sorghum. The studies both in vitro and in vivo reviewed have highlighted the potential role of their polyphenolic content as chemopreventive agents. Polyphenolic compounds including anthocyanins, tricin, protocatechualdehyde, avenanthramide, and 3-deoxyanthocyanins found in rice, barley, oats, and sorghum, respectively, were identified as compounds with potent bioactivity. Studies demonstrated that cereal polyphenols are likely to have chemopreventive activities, particularly those found in pigmented varieties. In conclusion, findings suggest that the consumption of pigmented cereals could potentially have an important role as a natural complementary cancer preventive therapeutic. However, further studies to develop a complete understanding of the mechanisms by which phenolic compounds inhibit cancerous cell proliferation are warranted.

Evidence-Based Review of BioBran/MGN-3 Arabinoxylan Compound as a Complementary Therapy for Conventional Cancer Treatment

INTRODUCTION

Conventional cancer treatment, including surgery, chemotherapy, and radiotherapy, may not be sufficient to eradicate all malignant cells and prevent recurrence. Intensive treatment often leads to a depressed immune system, drug resistance, and toxicity, hampering the treatment outcomes. BioBran/MGN-3 Arabinoxylan is a standardized arabinoxylan concentrate which has been proposed as a plant-based immunomodulator that can restore the tumor-induced disturbance of the natural immune system, including natural killer cell activity to fight cancer, complementing conventional therapies.

OBJECTIVES

To comprehensively review the available evidence on the effects and efficacies of MGN-3 as a complementary therapy for conventional cancer treatment.

METHODS

Systematic search of journal databases and gray literature for primary studies reporting the effects of MGN-3 on cancer and cancer treatment.

RESULTS

Thirty full-text articles and 2 conference abstracts were included in this review. MGN-3 has been shown to possess immunomodulating anticancer effects and can work synergistically with chemotherapeutic agents, in vitro. In murine models, MGN-3 has been shown to act against carcinogenic agents, and inhibit tumor growth, either by itself or in combination with other anticancer compounds. Fourteen successful MGN-3 treated clinical cases were found. Eleven clinical studies, including 5 nonrandomized, pre-post intervention studies and 6 randomized controlled trials (RCTs) were located. Reported effects include enhanced immunoprofile, reduced side effects, improved treatment outcomes; one RCT established significantly increased survival rates. There are no reports on adverse events on MGN-3. Most of the clinical trials are small studies with short duration.

CONCLUSION

There is sufficient evidence suggesting MGN-3 to be an effective immunomodulator that can complement conventional cancer treatment. However, more well-designed RCTs on MGN-3 are needed to strengthen the evidence base.

Phytochemical Profile of Brown Rice and Its Nutrigenomic Implications

Whole grain foods have been promoted to be included as one of the important components of a healthy diet because of the relationship between the regular consumption of whole-grain foods and reduced risk of chronic diseases. Rice is a staple food, which has been widely consumed for centuries by many Asian countries. Studies have suggested that brown rice is associated with a wide spectrum of nutrigenomic implications such as anti-diabetic, anti-cholesterol, cardioprotective and antioxidant. This is because of the presence of various phytochemicals that are mainly located in bran layers of brown rice. Therefore, this paper is a review of publications that focuses on the bioactive compounds and nutrigenomic implications of brown rice. Although current evidence supports the fact that the consumption of brown rice is beneficial for health, these studies are heterogeneous in terms of their brown rice samples used and population groups, which cause the evaluation to be difficult. Future clinical studies should focus on the screening of individual bioactive compounds in brown rice with reference to their nutrigenomic implications.

Nutrients and Oxidative Stress: Friend or Foe?

There are different types of nutritionally mediated oxidative stress sources that trigger inflammation. Much information indicates that high intakes of macronutrients can promote oxidative stress and subsequently contribute to inflammation via nuclear factor-kappa B- (NF-κB-) mediated cell signaling pathways. Dietary carbohydrates, animal-based proteins, and fats are important to highlight here because they may contribute to the long-term consequences of nutritionally mediated inflammation. Oxidative stress is a central player of metabolic ailments associated with high-carbohydrate and animal-based protein diets and excessive fat consumption. Obesity has become an epidemic and represents the major risk factor for several chronic diseases, including diabetes, cardiovascular disease (CVD), and cancer. However, the molecular mechanisms of nutritionally mediated oxidative stress are complex and poorly understood. Therefore, this review aimed to explore how dietary choices exacerbate or dampen the oxidative stress and inflammation. We also discussed the implications of oxidative stress in the adipocyte and glucose metabolism and obesity-associated noncommunicable diseases (NCDs). Taken together, a better understanding of the role of oxidative stress in obesity and the development of obesity-related NCDs would provide a useful approach. This is because oxidative stress can be mediated by both extrinsic and intrinsic factors, hence providing a plausible means for the prevention of metabolic disorders.

Sustained release of anticancer agent phytic acid from its chitosan-coated magnetic nanoparticles for drug-delivery system

Chitosan (CS) iron oxide magnetic nanoparticles (MNPs) were coated with phytic acid (PTA) to form phytic acid-chitosan-iron oxide nanocomposite (PTA-CS-MNP). The obtained nanocomposite and nanocarrier were characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, vibrating sample magnetometry, transmission electron microscopy, and thermogravimetric and differential thermogravimetric analyses. Fourier transform infrared spectra and thermal analysis of MNPs and PTA-CS-MNP nanocomposite confirmed the binding of CS on the surface of MNPs and the loading of PTA in the PTA-CS-MNP nanocomposite. The coating process enhanced the thermal stability of the anticancer nanocomposite obtained. X-ray diffraction results showed that the MNPs and PTA-CS-MNP nanocomposite are pure magnetite. Drug loading was estimated using ultraviolet-visible spectroscopy and showing a 12.9% in the designed nanocomposite. Magnetization curves demonstrated that the synthesized MNPs and nanocomposite were superparamagnetic with saturation magnetizations of 53.25 emu/g and 42.15 emu/g, respectively. The release study showed that around 86% and 93% of PTA from PTA-CS-MNP nanocomposite could be released within 127 and 56 hours by a phosphate buffer solution at pH 7.4 and 4.8, respectively, in a sustained manner and governed by pseudo-second order kinetic model. The cytotoxicity of the compounds on HT-29 colon cancer cells was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The HT-29 cell line was more sensitive against PTA-CS-MNP nanocomposite than PTA alone. No cytotoxic effect was observed on normal cells (3T3 fibroblast cells). This result indicates that PTA-CS-MNP nanocomposite can inhibit the proliferation of colon cancer cells without causing any harm to normal cell.