Impact of dietary components on NK and Treg cell function for cancer prevention

Discovery of cancer-preventive juices reactivating RB functions

BACKGROUND

Recent advances have been achieved in the genetic diagnosis and therapies against malignancies due to a better understanding of the molecular mechanisms underlying carcinogenesis. Since active preventive methods are currently insufficient, the further development of appropriate preventive strategies is desired.

METHODS

We searched for drinks that reactivate the functions of tumor-suppressor retinoblastoma gene (RB) products and exert anti-inflammatory and antioxidant effects. We also examined whether lactic acid bacteria increased the production of the cancer-specific anti-tumor cytokine, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), in human, and examined whether the RB-reactivating drinks with lactic acid bacteria decreased azoxymethane-induced rat colon aberrant crypt foci (ACF) and aberrant crypts (ACs) in vivo.

RESULTS

Kakadu plum juice and pomegranate juice reactivated RB functions, which inhibited the growth of human colon cancer LIM1215 cells by G1 phase arrest. These juices also exerted anti-inflammatory and antioxidant effects. Lactiplantibacillus (L.) pentosus S-PT84 was administered to human volunteers and increased the production of TRAIL. In an in vivo study, Kakadu plum juice with or without pomegranate juice and S-PT84 significantly decreased azoxymethane-induced rat colon ACF and ACs.

CONCLUSIONS

RB is one of the most important molecules suppressing carcinogenesis, and to the best of our knowledge, this is the first study to demonstrate that natural drinks reactivated the functions of RB. As expected, Kakadu plum juice and pomegranate juice suppressed the growth of LIM1215 cells by reactivating the functions of RB, and Kakadu plum juice with or without pomegranate juice and S-PT84 inhibited rat colon ACF and ACs. Therefore, this mixed juice has potential as a novel candidate for cancer prevention.

Can Nutritional Supports Beneficial in Other Viral Diseases Be Favorable for COVID-19?

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus-2 (SARS-COV-2), has rapidly spread worldwide, causing many deaths, the number of which continues to increase. Global public health organizations and governments have advised on the adoption of various handwashing and hygiene guidelines, use of masks, and social distancing, along with isolation or lockdown protocols to prevent SARS-COV-2 spread. There are vaccines and drugs that are confirmed but still many human suffer from this disease. Important risk factors for SARS-COV-2 infection are similar to other viral infectious diseases as including influenza, hepatitis B, acquired immunodeficiency syndrome, and other lung infections. These diseases might be related to poor nutritional support, affecting the patient outcomes against COVID-19. In this review, we discuss some of the nutritional therapies currently being investigated for infectious diseases. Studies have shown that nutrition has the potential to prevent and mitigate viral infections. Micronutrients (vitamins A, B6, B12, C, D, and E, B9, and trace elements, such as iron, zinc, copper, selenium, magnesium, and polyphenols) and macronutrients (carbohydrates, prebiotics, probiotics, protein [amino acids], and lipids [fatty acids]) affect the whole body, including the immune system, preventing viral entry and modulating clinical symptoms. This review discusses the importance of nutrition as a strategy to understand food groups and key nutrients that may affect the clinical outcomes of COVID-19 patients during the ongoing pandemic. Scientists believe that the likelihood of another pandemic is imminent. COVID-19 remains important and scientists believe it will continue will in the future. We emphasize the lack of studies on the nutritional impact of COVID-19 in terms of nutrition, even though nutritional interventions has been shown to have many advantages during the treatment of viral infections.

Personalized Nutrition as a Key Contributor to Improving Radiation Response in Breast Cancer

Understanding metabolic and immune regulation inherent to patient populations is key to improving the radiation response for our patients. To date, radiation therapy regimens are prescribed based on tumor type and stage. Patient populations who are noted to have a poor response to radiation such as those of African American descent, those who have obesity or metabolic syndrome, or senior adult oncology patients, should be considered for concurrent therapies with radiation that will improve response. Here, we explore these populations of breast cancer patients, who frequently display radiation resistance and increased mortality rates, and identify the molecular underpinnings that are, in part, responsible for the radiation response and that result in an immune-suppressive tumor microenvironment. The resulting immune phenotype is discussed to understand how antitumor immunity could be improved. Correcting nutrient deficiencies observed in these populations should be considered as a means to improve the therapeutic index of radiation therapy.

Lifestyle Adjustments in Long-COVID Management: Potential Benefits of Plant-Based Diets

PURPOSE OF REVIEW

The SARS-CoV-2-pandemic has caused mortality and morbidity at an unprecedented global scale. Many patients infected with SARS-CoV-2 continue to experience symptoms after the acute phase of infection and report fatigue, sleep difficulties, anxiety, and depression as well as arthralgia and muscle weakness. Summarized under the umbrella term "long-COVID," these symptoms may last weeks to months and impose a substantial burden on affected individuals. Dietary approaches to tackle these complications have received comparably little attention. Although plant-based diets in particular were shown to exert benefits on underlying conditions linked to poor COVID-19 outcomes, their role with regard to COVID-19 sequelae is yet largely unknown. Thus, this review sought to investigate whether a plant-based diet could reduce the burden of long-COVID.

RECENT FINDINGS

The number of clinical trials investigating the role of plant-based nutrition in COVID-19 prevention and management is currently limited. Yet, there is evidence from pre-pandemic observational and clinical studies that a plant-based diet may be of general benefit with regard to several clinical conditions that can also be found in individuals with COVID-19. These include anxiety, depression, sleep disorders, and musculoskeletal pain. Adoption of a plant-based diet leads to a reduced intake in pro-inflammatory mediators and could be one accessible strategy to tackle long-COVID associated prolonged systemic inflammation. Plant-based diets may be of general benefit with regard to some of the most commonly found COVID-19 sequelae. Additional trials investigating which plant-based eating patterns confer the greatest benefit in the battle against long-COVID are urgently warranted.

Black Raspberries Suppress Colorectal Cancer by Enhancing Smad4 Expression in Colonic Epithelium and Natural Killer Cells

Innate immune cells in the tumor microenvironment have been proposed to control the transition from benign to malignant stages. In many cancers, increased infiltration of natural killer (NK) cells associates with good prognosis. Although the mechanisms that enable NK cells to restrain colorectal cancer (CRC) are unclear, the current study suggests the involvement of Smad4. We found suppressed Smad4 expression in circulating NK cells of untreated metastatic CRC patients. Moreover, NK cell-specific Smad4 deletion promoted colon adenomas in DSS-treated ApcMin/+ mice and adenocarcinomas in AOM/DSS-treated mice. Other studies have shown that Smad4 loss or weak expression in colonic epithelium associates with poor survival in CRC patients. Therefore, targeting Smad4 in both colonic epithelium and NK cells could provide an excellent opportunity to manage CRC. Toward this end, we showed that dietary intervention with black raspberries (BRBs) increased Smad4 expression in colonic epithelium in patients with FAP or CRC and in the two CRC mouse models. Also, benzoate metabolites of BRBs, such as hippurate, upregulated Smad4 and Gzmb expression that might enhance the cytotoxicity of primary human NK cells. Of note, increased levels of hippurate is a metabolomic marker of a healthy gut microbiota in humans, and hippurate also has antitumor effects. In conclusion, our study suggests a new mechanism for the action of benzoate metabolites derived from plant-based foods. This mechanism could be exploited clinically to upregulate Smad4 in colonic epithelium and NK cells, thereby delaying CRC progression.

Outcomes Assessment of Sustainable and Innovatively Simple Lifestyle Modification at the Workplace - Drinking Electrolyzed-Reduced Water (OASIS-ERW): A Randomized, Double-Blind, Placebo-Controlled Trial

Oxidative stress has been associated with many diseases as well as aging. Electrolyzed-reduced water (ERW) has been suggested to reduce oxidative stress and improve antioxidant potential. This study investigated the effects of drinking ERW on biomarkers of oxidative stress and health-related indices in healthy adults. We conducted a randomized, double-blind, placebo-controlled clinical trial on 65 participants, who were allocated into two groups. Of these, 61 received intervention (32 with ERW and 29 MW [mineral water]). All participants were instructed to drink 1.5 L/day of ERW or MW for eight weeks. Biomarkers of oxidative stress and health-related indices were assessed at baseline as well as after 4 weeks and 8 weeks of intervention. Of the primary outcome variables assessed, diacron-reactive oxygen metabolites (d-ROMs) and biological antioxidant potential showed a significant interaction between the groups and time, with d-ROMs levels significantly decreased at 8 weeks in ERW compared to those in MW. Among the secondary outcome variables, total, visceral, and subcutaneous fat mass significantly changed over time, with a significant association observed between the groups and time. Thus, daily ERW consumption may be a potential consideration for a sustainable and innovatively simple lifestyle modification at the workplace to reduce oxidative stress, increase antioxidant potential, and decrease fat mass.

Effect of immune-enhancing enteral nutrition formula enriched with plant-derived n-3 fatty acids on natural killer cell activity in rehabilitation patients

BACKGROUND/OBJECTIVES

Enteral nutrition formulas with immune-enhancing nutrients, such as n-3 fatty acids, may manage patients' nutritional status and pathophysiological processes. The aim of our study was to investigate natural killer (NK) cell activity alterations and related cytokine changes resulting from feeding with soybean oil-containing enteral nutrition formula (control group) and plant-derived n-3 fatty acid-enriched enteral nutrition formula.

SUBJECTS/METHODS

Subjects participated for 14 consecutive days and consumed enteral formula containing canola and flaxseed oil (n3EN, test group) in nonsurgical patients hospitalized for rehabilitation. Blood samples were collected on the first day and 14 days after the consumption of each formula daily, and anthropometric parameters were collected. Hematology and biochemical values were analyzed, and NK cell activities and serum cytokine concentration were measured. A total of sixty subjects were included in the analysis, excluding dropouts.

RESULTS

No significant differences were found in biochemical parameters. The n3EN group's NK cell activities at effector:tumor cell ratios of 10:1, 5:1, 2.5:1 and 0.625:1 were significantly higher than those of the control group after two weeks (P < 0.05). However, there were no statistically significant differences in serum cytokine interleukin (IL)-12, interferon-γ, IL-1β, IL-6 and tumor necrosis factor-α values between the two groups.

CONCLUSIONS

In conclusion, this study elucidates the beneficial effects of plant-derived n-3 fatty acid supplementation in enteral formula on NK cell activity.

Biomodulina T partially restores immunosenescent CD4 and CD8 T cell compartments in the elderly

The changes that occur in the immune system with aging are commonly termed immunosenescence. Immunosenescence affects almost all components and functions of the immune response. The most commonly described change is a decrease in numbers and proportions of naïve T cells combined with the increase of terminally differentiated T lymphocytes, mainly affecting CD8+ T cells. The changes in the naïve T cell compartment are principally attributed to thymic involution and lifelong chronic antigen stimulation, among other triggers. Several strategies such as hormonal products, thymic peptides, or cytokines have been proposed for the restoration of the immune system. Here we show the effects of Biomodulina T (BT) on several populations of the immune system when administered to elderly patients diagnosed with recurrent respiratory infections. BT is a polypeptide fraction of bovine thymus, a Cuban product that obtained sanitary registration in 1994 for its immunomodulatory effects. We found that CD4+ naïve T, CD8+ stem cell-like memory (SCM) T, CD4+ recent thymic emigrants (RTE) T and CD4+ CD31+ naïve T cells increased with the administration of BT, whereas CD4+ and CD8+ T cells expressing PD1 decreased after the treatment with BT. Additionally, the proliferative capacity of CD4+ T cells measured by Ki67 expression, and the CD4+ T cell ability to produce IFN-γ were also improved by BT. Moreover, BT did not increase CD4+ Tregs. Altogether, these findings suggest that BT administration is a promising strategy for immune restoration in elderly patients and improvement of immunotherapeutic potential in cancer patients.

Hesperidin Protects Against Intestinal Inflammation by Restoring Intestinal Barrier Function and Up-Regulating Treg Cells

SCOPE

Hesperidin is an important natural phenolic compound and is considered beneficial to health. The purpose of this study is to investigate the protective effects of hesperidin on DSS-induced colitis in mice and Caco-2 cells.

METHODS

The DSS-induced colitis mice are assigned to 10, 20, and 40 mg kg^-g hesperidin diets after DSS treatment. For in vitro experiments, Caco-2 cells are treated with TNF-α/ IFN-γ for 48 h without or with hesperidin.

RESULTS

Hesperidin supplementation ameliorates DSS-induced colitis. Specifically, hesperidin ameliorates intestinal inflammation through decreasing MDA activity and enhancing SOD and GSH activities. Hesperidin also obviously upregulates Nrf2 antioxidant pathway and increases the protein expression of HO-1 and NQO1. Additionally, hesperidin significantly reduces the levels of inflammatory factors and increases the levels of anti-inflammatory factors in the colon tissues. Further analysis shows that hesperidin can improve the expression of tight junction proteins and intestinal permeability, as well as increases the Treg population. In Caco-2 cells, it is shown that hesperidin prevents TNF-α/IFN-γ-induced reduction in TEER and morphological disruption. Moreover, hesperidin also decreases the epithelial permeability and suppresses proinflammatory responses.

CONCLUSION

Hesperidin can protect against intestinal inflammation via enhanced Nrf2 antioxidant pathway, increases the Treg population, and restores intestinal barrier function.

The immunomodulatory potential of natural compounds in tumor-bearing mice and humans

Cancer is considered a fetal disease caused by uncontrolled proliferation and progression of abnormal cells. The most efficient cancer therapies suppress tumor growth, prevent progression and metastasis, and are minimally toxic to normal cells. Natural compounds have shown a variety of chemo-protective effects alone or in combination with standard cancer therapies. Along with better understanding of the dynamic interactions between our immune system and cancer development, nutritional immunology-the use of natural compounds as immunomodulators in cancer patients-has begun to emerge. Cancer cells evolve strategies that target many aspects of the immune system to escape or even edit immune surveillance. Therefore, the immunesuppressive tumor microenvironment is a major obstacle in the development of cancer therapies. Because interaction between the tumor microenvironment and the immune system is a complex topic, this review focuses mainly on human clinical trials and animal studies, and it highlights specific immune cells and their cytokines that have been modulated by natural compounds, including carotenoids, curcumin, resveratrol, EGCG, and β-glucans. These natural compounds have shown promising immune-modulating effects, such as inhibiting myeloid-derived suppressor cells and enhancing natural killer and cytolytic T cells, in tumor-bearing animal models, but their efficacy in cancer patients remains to be determined.

Carotenoid supplementation and retinoic acid in immunoglobulin A regulation of the gut microbiota dysbiosis

Dysbiosis, a broad spectrum of imbalance of the gut microbiota, may progress to microbiota dysfunction. Dysbiosis is linked to some human diseases, such as inflammation-related disorders and metabolic syndromes. However, the underlying mechanisms of the pathogenesis of dysbiosis remain elusive. Recent findings suggest that the microbiome and gut immune responses, like immunoglobulin A production, play critical roles in the gut homeostasis and function, and the progression of dysbiosis. In the past two decades, much progress has been made in better understanding of production of immunoglobulin A and its association with commensal microbiota. The present minireview summarizes the recent findings in the gut microbiota dysbiosis and dysfunction of immunoglobulin A induced by the imbalance of pathogenic bacteria and commensal microbiota. We also propose the potentials of dietary carotenoids, such as β-carotene and astaxanthin, in the improvement of the gut immune system maturation and immunoglobulin A production, and the consequent promotion of the gut health. Impact statement The concept of carotenoid metabolism in the gut health has not been well established in the literature. Here, we review and discuss the roles of retinoic acid and carotenoids, including pro-vitamin A carotenoids and xanthophylls in the maturation of the gut immune system and IgA production. This is the first review article about the carotenoid supplements and the metabolites in the regulation of the gut microbiome. We hope this review would provide a new direction for the management of the gut microbiota dysbiosis by application of bioactive carotenoids and the metabolites.

Vitamin D receptor and progesterone receptor protein and gene expression in papillary thyroid carcinomas: associations with histological features

PURPOSE

Vitamin D receptor (VDR) and progesterone receptor (PR) expression has been described in papillary thyroid carcinoma (PTC) but data regarding association with tumor histological characteristics and localization of the protein expression are scarce.

MATERIALS AND METHODS

Formalin-fixed, paraffin-embedded specimens from 45 patients with PTC (cases) were retrieved and tumor histological data were recorded. We analyzed gene and protein expression of VDR and PR and gene expression of vitamin D-inactivating 24-hyroxylase (CYP24A1) and the activating 1-alpha-hydroxylase (CYP27B1) enzymes in follicular cancer cells and the adjacent non-neoplastic thyroid tissue (NNTT).

RESULTS

VDR mRNA and protein expression was higher in PTC compared with NNTT (p < 0.05). The protein was globally localized in the cytoplasm and cell membranes of the neoplastic cells in all cases, with differences in intensity. Cytoplasmic positivity was stronger in the majority of cases. Membranous positivity was also evident in cases, whereas in NNTT was generally weak and in a low percentage of the cells. Expression of CYP 24A1, but not CYP27B1, was increased in approximately all PTC specimens and was associated with lymph node metastasis and extrathyroidal extension. PR mRNA was increased in 34% and protein expression was present in 57% of cases, and none of NNTT. PR, but not VDR, mRNA expression was significantly associated with the tumor size (r = 0.645, p = 0.007).

CONCLUSIONS

We provide evidence for the expression pattern of VDR, PR and CYP24A1 in the progression of PTC. Rapid anti-tumor responses of vitamin D in PTC may be blocked due to inactivation of local vitamin D metabolism.

Potential Impact of Nutrition on Immune System Recovery from Heavy Exertion: A Metabolomics Perspective

This review describes effective and ineffective immunonutrition support strategies for the athlete, with a focus on the benefits of carbohydrates and polyphenols as determined from metabolomics-based procedures. Athletes experience regular cycles of physiological stress accompanied by transient inflammation, oxidative stress, and immune perturbations, and there are increasing data indicating that these are sensitive to nutritional influences. The most effective nutritional countermeasures, especially when considered from a metabolomics perspective, include acute and chronic increases in dietary carbohydrate and polyphenols. Carbohydrate supplementation reduces post-exercise stress hormone levels, inflammation, and fatty acid mobilization and oxidation. Ingestion of fruits high in carbohydrates, polyphenols, and metabolites effectively supports performance, with added benefits including enhancement of oxidative and anti-viral capacity through fruit metabolites, and increased plasma levels of gut-derived phenolics. Metabolomics and lipidomics data indicate that intensive and prolonged exercise is associated with extensive lipid mobilization and oxidation, including many components of the linoleic acid conversion pathway and related oxidized derivatives called oxylipins. Many of the oxylipins are elevated with increased adiposity, and although low in resting athletes, rise to high levels during recovery. Future targeted lipidomics-based studies will help discover whether n-3-polyunsaturated fatty acid (n-3-PUFA) supplementation enhances inflammation resolution in athletes post-exercise.

Plasma n-6 Fatty Acid Levels Are Associated With CD4 Cell Counts, Hospitalization, and Mortality in HIV-Infected Patients

BACKGROUND

Fatty acids, including n-6 series, modulate immune function, but their effect on CD4 cell counts, death, or hospitalization in HIV-infected patients on antiretroviral therapy is unknown.

METHODS

In a randomized trial for effects of multivitamins in HIV-infected patients in Uganda, we used gas chromatography to measure plasma n-6 fatty acids at baseline; determined CD4 counts at baseline, 3, 6, 12, and 18 months; and recorded hospitalization or death events. The associations of fatty acids with CD4 counts and events were analyzed using repeated-measures analysis of variance and Cox regression, respectively.

RESULTS

Among 297 patients with fatty acids measurements, 16 patients died and 69 were hospitalized within 18 months. Except for linoleic acid, n-6 fatty acids levels were positively associated with CD4 counts at baseline but not during follow-up. In models that included all 5 major n-6 fatty acids, age; sex; body mass index; anemia status; use of antiretroviral therapy, multivitamin supplements, and alcohol; and the risk of death or hospitalization decreased significantly with an increase in linoleic acid and gamma-linolenic acid levels, whereas associations for dihomo-gamma-linolenic acid, arachidonic acid, and aolrenic acid were null. The hazard ratios (95% confidence intervals) per 1 SD increase in linoleic acid and gamma-linolenic acid were 0.73 (0.56-0.94) and 0.51 (0.36-0.72), respectively. Gamma-linolenic acid remained significant (hazard ratio = 0.51; 95% confidence interval: 0.35 to 0.68) after further adjustment for other plasma fatty acids.

CONCLUSIONS

Lower levels of gamma-linolenic acid are associated with lower CD4 counts and an increased risk of death or hospitalization. These results suggest a potential for using n-6 fatty acids to improve outcomes from antiretroviral therapy.

Augmentation of Cytolytic Activity in Murine Natural Killer Cells and Inhibition of Tumor Growth by the Ethanol Fraction of Oyster Extract

A reduced number and/or reduced activity of natural killer (NK) cells, which are important for defense against a variety of cancers and viral infections, occur under various stress conditions and in patients with various diseases. In this article, we report that the 30% to 50% ethanol precipitate of oyster extract (EPOE50) dose-dependently enhanced the activity of mouse spleen NK cells in vitro and in vivo. The activity of EPOE50 was eluted with a molecular weight of about 2000 by gel filtration and was inactivated by periodate but not by proteinase K. The activity of highly purified NK cells was also augmented by EPOE50 but not by oligodeoxyribonucleotide 1585, which mimics bacterial DNA. Administration of EPOE50 to mice stimulated splenic NK cell activity without a change in splenic NK cell populations. Although the proliferation of B16 tumor cells in vitro was slightly stimulated by EPOE50, the growth of B16 melanoma in vivo was dose-dependently suppressed by administration of EPOE50. Taken together, our results indicate that EPOE50 augmented NK cell activity and that its administration to mice inhibited tumor growth presumably through the activation of NK cells and also suggest that the active substance is a sugar-containing oligomer or polymer and is not of bacterial origin.