Nutrition interventions for healthy ageing across the lifespan: a conference report.

Thanks to advances in modern medicine over the past century, the world's population has experienced a marked increase in longevity. However, disparities exist that lead to groups with both shorter lifespan and significantly diminished health, especially in the aged. Unequal access to proper nutrition, healthcare services, and information to make informed health and nutrition decisions all contribute to these concerns. This in turn has hastened the ageing process in some and adversely affected others' ability to age healthfully. Many in developing as well as developed societies are plagued with the dichotomy of simultaneous calorie excess and nutrient inadequacy. This has resulted in mental and physical deterioration, increased non-communicable disease rates, lost productivity and quality of life, and increased medical costs. While adequate nutrition is fundamental to good health, it remains unclear what impact various dietary interventions may have on improving healthspan and quality of life with age. With a rapidly ageing global population, there is an urgent need for innovative approaches to health promotion as individual's age. Successful research, education, and interventions should include the development of both qualitative and quantitative biomarkers and other tools which can measure improvements in physiological integrity throughout life. Data-driven health policy shifts should be aimed at reducing the socio-economic inequalities that lead to premature ageing. A framework for progress has been proposed and published by the World Health Organization in its Global Strategy and Action Plan on Ageing and Health. This symposium focused on the impact of nutrition on this framework, stressing the need to better understand an individual's balance of intrinsic capacity and functional abilities at various life stages, and the impact this balance has on their mental and physical health in the environments they inhabit.

Healthy ageing: the natural consequences of good nutrition-a conference report.

Many countries are witnessing a marked increase in longevity and with this increased lifespan and the desire for healthy ageing, many, however, suffer from the opposite including mental and physical deterioration, lost productivity and quality of life, and increased medical costs. While adequate nutrition is fundamental for good health, it remains unclear what impact various dietary interventions may have on prolonging good quality of life. Studies which span age, geography and income all suggest that access to quality foods, host immunity and response to inflammation/infections, impaired senses (i.e., sight, taste, smell) or mobility are all factors which can limit intake or increase the body's need for specific micronutrients. New clinical studies of healthy ageing are needed and quantitative biomarkers are an essential component, particularly tools which can measure improvements in physiological integrity throughout life, thought to be a primary contributor to a long and productive life (a healthy "lifespan"). A framework for progress has recently been proposed in a WHO report which takes a broad, person-centered focus on healthy ageing, emphasizing the need to better understand an individual's intrinsic capacity, their functional abilities at various life stages, and the impact by mental, and physical health, and the environments they inhabit.

Optimal nutrition and the ever-changing dietary landscape: a conference report.

The field of nutrition has evolved rapidly over the past century. Nutrition scientists and policy makers in the developed world have shifted the focus of their efforts from dealing with diseases of overt nutrient deficiency to a new paradigm aimed at coping with conditions of excess-calories, sedentary lifestyles and stress. Advances in nutrition science, technology and manufacturing have largely eradicated nutrient deficiency diseases, while simultaneously facing the growing challenges of obesity, non-communicable diseases and aging. Nutrition research has gone through a necessary evolution, starting with a reductionist approach, driven by an ambition to understand the mechanisms responsible for the effects of individual nutrients at the cellular and molecular levels. This approach has appropriately expanded in recent years to become more holistic with the aim of understanding the role of nutrition in the broader context of dietary patterns. Ultimately, this approach will culminate in a full understanding of the dietary landscape-a web of interactions between nutritional, dietary, social, behavioral and environmental factors-and how it impacts health maintenance and promotion.

Nutrient reference value: non-communicable disease endpoints--a conference report.

Nutrition is complex-and seemingly getting more complicated. Most consumers are familiar with "essential nutrients," e.g., vitamins and minerals, and more recently protein and important amino acids. These essential nutrients have nutrient reference values, referred to as dietary reference intakes (DRIs) developed by consensus committees of scientific experts convened by the Institute of Medicine of the National Academy of Sciences, Engineering, and Medicine and carried out by the Food and Nutrition Board. The DRIs comprise a set of four nutrient-based reverence values, the estimated average requirements, the recommended dietary allowances (RDAs), the adequate intakes and the tolerable upper intake levels for micronutrient intakes and an acceptable macronutrient distribution range for macronutrient intakes. From the RDA, the US Food and Drug Administration (FDA) derives a labeling value called the daily value (DV), which appears on the nutrition label of all foods for sale in the US. The DRI reports do not make recommendations about whether the DV labeling values can be set only for what have been defined to date as "essential nutrients." For example, the FDA set a labeling value for "dietary fiber" without having the DV. Nutrient reference values-requirements are set by Codex Alimentarius for essential nutrients, and regulatory bodies in many countries use these Codex values in setting national policy for recommended dietary intakes. However, the focus of this conference is not on essential nutrients, but on the "nonessential nutrients," also termed dietary bioactive components. They can be defined as "Constituents in foods or dietary supplements, other than those needed to meet basic human nutritional needs, which are responsible for changes in health status (Office of Disease Prevention and Health Promotion, Office of Public Health and Science, Department of Health and Human Services in Fed Regist 69:55821-55822, 2004)." Substantial and often persuasive scientific evidence does exist to confirm a relationship between the intake of a specific bioactive constituent and enhanced health conditions or reduced risk of a chronic disease. Further, research on the putative mechanisms of action of various classes of bioactives is supported by national and pan-national government agencies, and academic institutions, as well as functional food and dietary supplement manufacturers. Consumers are becoming educated and are seeking to purchase products containing bioactives, yet there is no evaluative process in place to let the public know how strong the science is behind the benefits or the quantitative amounts needed to achieve these beneficial health effects or to avoid exceeding the upper level (UL). When one lacks an essential nutrient, overt deficiency with concomitant physiological determents and eventually death are expected. The absence of bioactive substances from the diet results in suboptimal health, e.g., poor cellular and/or physiological function, which is relative and not absolute. Regrettably at this time, there is no DRI process to evaluate bioactives, although a recent workshop convened by the National Institutes of Health (Options for Consideration of Chronic Disease Endpoints for Dietary Reference Intakes (DRIs); March 10-11, 2015; http://health.gov/dietaryguidelines/dri/ ) did explore the process to develop DVs for nutrients, the lack of which result in increased risk of chronic disease (non-communicable disease) endpoints. A final report is expected soon. This conference (CRN-International Scientific Symposium; "Nutrient Reference Value-Non-Communicable Disease (NRV-NCD) Endpoints," 20 November in Kronberg, Germany; http://www.crn-i.ch/2015symposium/ ) explores concepts related to the Codex NRV process, the public health opportunities in setting NRVs for bioactive constituents, and further research and details on the specific class of bioactives, n-3 long-chain polyunsaturated fatty acids (also termed omega-3 fatty acids) and their constituents, specifically docosahexaenoic acid and eicosapentaenoic acid.

Safety evaluation of a natural tomato oleoresin extract derived from food-processing tomatoes.

Experimental and epidemiological studies indicate that consumption of tomato products containing high amounts of lycopene is associated with lowered cancer risk. The protective effects of lycopene may be related to its antioxidant potential. Lycopene has been demonstrated to inhibit oxidation. A proprietary, natural tomato oleoresin extract (NTOE), is a purified tomato oleoresin containing 6% lycopene produced from tomatoes. NTOE was evaluated for toxicological effects, and found the 50% lethal dose (LD(50)), derived from the acute oral toxicity study, was greater than 5000 mg/kg body weight. The no-observed-adverse-effect level (NOAEL) derived from the 13-week study was 4500 mg/kg/day. Acute dermal toxicity study of NTOE found no toxicity at 2000 mg/kg body weight. NTOE lacked dermal irritation in the rabbit model, but was found to have moderate eye-irritant capabilities. NTOE tested at 5% (w/w) in petroleum jelly was a moderate sensitizer in the guinea pig model. There was no evidence of mutagenic potential up to 5000 microg/plate, as determined by the Ames assay. These results demonstrate the inability of NTOE to produce oral, dermal or mutagenic toxicity in animal models at doses greater than 300 times the normal human consumption of lycopene. Consumption analysis of lycopene-containing foods estimated mean daily intake of lycopene at 8.2mg/day.

Chronic toxicity and oncogenicity of N-methylpyrrolidone (NMP) in rats and mice by dietary administration.

A two-year feeding study in rats and an 18-month feeding study in mice were conducted to evaluate the potential chronic toxicity and oncogenicity of NMP in Crl:CD (SD)BR rats and B6C3F1/CrlBR mice. Groups of 62 male and female rats were administered diets containing 0, 1600, 5000, or 15,000 ppm of NMP for approximately 2 years. Groups of 50 male and female mice were administered diets containing 0, 600, 1200, or 7200 ppm NMP for approximately 18 months. In vivo parameters were evaluated weekly during the first 3 months of the study, and every other week or monthly during the remainder of the study. For rats, an ophthalmoscopic examination was conducted prior to study start and near the end of the study. Periodically, blood samples were collected from rats and mice for determination of leukocyte differential counts, and from mice for red blood cell morphology. After approximately 2 years of dietary administration in rats and 18 months in mice, all surviving animals were sacrificed. Selected tissues were processed for morphological evaluation. Over the course of the two-year study in rats, test substance-related decrements in body weight and weight gain occurred in 15,000 ppm males and females, which correlated with decreased food consumption and food efficiency. A toxicologically significant, test substance-related increase in the incidence of severe chronic progressive nephropathy occurred in 15,000 ppm males. Several morphological changes noted grossly and/or microscopically were secondary to the increased severity of chronic progressive nephropathy. NMP was not oncogenic in male or female rats at dietary concentrations of 15,000 ppm and below. A test substance-related decrease in the percentage of 15,000 ppm males surviving to the end of the two-year study compared to the control group resulted from the higher incidence of severe chronic progressive nephropathy. However, a sufficient population of 15,000 ppm rats were at risk for potential oncogenicity, so the lower survival did not impair the ability to detect an oncogenic response in this study. There were no adverse, test substance-related effects on the incidences of clinical observations, ophthalmic observations, or differential leukocyte counts in males or females, or on survival of females at any dietary concentration. Male and female mice administered dietary concentrations of 7200 ppm had significantly increased liver weight, significantly increased incidence of hepatocellular adenoma, and significantly increased foci of cellular alteration in the liver. At 7200 ppm, male mice also had an increased incidence of hepatocellular carcinoma while the increased incidence of hepatocellular carcinoma in female mice fell within the historical control range. In addition, the incidence of hepatocellular hypertrophy was increased in 7200 ppm males. Liver weight and hepatocellular hypertrophy were also increased in 1200 ppm males. There were no adverse, test substance-related effects on the incidences of clinical observations, food consumption, body weight, differential leukocyte counts, red blood cell morphology, or survival in either males or females at any dietary concentration. Under the conditions of the study, the no-observed-effect level for NMP was 5000 ppm for male and female rats, 600 ppm for male mice, and 1200 ppm for female mice.

90-day subchronic toxicity study in rats and mice fed N-methylpyrrolidone (NMP) including neurotoxicity evaluation in rats.

In mice, there were no effects on body weight or food consumption. As observed in rats, mice fed 2,500 or 7,500 ppm exhibited a change in urine coloration which was not associated with morphological changes in cholesterol, triglycerides, calcium, and alkaline phosphatase occurred at 28 days but not 90 days. These changes are thus assessed as being of minor toxicological relevance. Liver weights were elevated in males fed 2,500 or 7,500 ppm and centrilobular hypertrophy was seen in both sexes fed 7,500 ppm. These changes may be regarded as an adaptation process but are clearly related to NMP exposure. Other toxicological endpoints examined were unaffected by NMP. The NOAEL was 3,000 ppm for both sexes of rats based on body weight effects and changes in 3 neurobehavioral parameters (males only) at higher feeding levels. In mice, the NOAEL was 1,000 ppm based on liver responses to higher concentrations.

Assessment of Herpesvirus saimiri as a potential human gene therapy vector.

Herpesvirus saimiri has characteristics that make it amenable to development as a gene therapy vector. The viral genome is thought to be capable of accommodating large quantities of heterologous DNA while the virus itself can infect many different cell types. Virus infection has been shown in many cases to be persistent by virtue of episomal maintenance in the target cell. In this article we examine the ability of nonselectable recombinant viruses expressing the beta-galactosidase gene product to infect a variety of human cells and demonstrate that this virus could be developed as an alternative hematopoietic stem cell gene therapy vector. In contrast to earlier observations, we demonstrate by a number of methods that the virus has the ability to replicate in many human cell types, suggesting the need for the development of a disabled virus for use as a gene therapy vector.

The herpesvirus saimiri ORF50 gene, encoding a transcriptional activator homologous to the Epstein-Barr virus R protein, is transcribed from two distinct promoters of different temporal phases.

The mRNA species encoding the herpesvirus saimiri (HVS) homolog of the Epstein-Barr virus R transcriptional activator (termed ORF50) have been identified and used to determine transcriptional start sites within the gene. The first transcript is spliced and starts from a promoter within ORF49 containing a single intron; the second is produced from a promoter within the second exon and is in the same reading frame. The spliced transcript is detected at early times during productive virus replication in OMK cells, whereas the nonspliced transcript is detected later. The spliced transcript is fivefold-more potent in activating the delayed-early ORF6 promoter; the function of the nonspliced transcript is unclear. Thus, the role of this protein in activating herpesvirus saimiri from the latent state may differ significantly from that of the Epstein-Barr virus R protein.

Carcinogenic risks of inorganic arsenic in perspective.

Induction of cancer by inorganic arsenic occurs inconsistently between species and between routes of exposure, and it exhibits different dose-response relationships between different target organs. Inhaled or ingested arsenic causes cancer in humans but not in other species. Inhaled arsenic primarily induces lung cancer, whereas ingested arsenic induces cancer at multiple sites, including the skin and various other organs. Cancer potency appears to vary by route of exposure (ingestion or inhalation) and by organ site, and increases markedly at higher exposures in some instances. To understand what might explain these inconsistencies, we reviewed several hypotheses about the mechanism of cancer induction by arsenic. Arsenic disposition does not provide satisfactory explanations. Induction of cell proliferation by arsenic is a mechanism of carcinogenesis that is biologically plausible and compatible with differential effects for species or differential dose rates for organ sites. The presence of other carcinogens, or risk modifiers, at levels that correlate with arsenic in drinking water supplies, may be a factor in all three inconsistencies: interspecies specificity, organ sensitivity to route of administration, and organ sensitivity to dose rate.

A transient three-plasmid expression system for the production of high titer retroviral vectors.

We have constructed a series of MLV-based retroviral vectors and packaging components expressed from the CMV promoter and carried on plasmids containing SV40 origins of replication. These two features greatly enhanced retroviral gene expression when introduced into cell lines carrying the SV40 large T antigen. The two packaging components, gag-pol and env, were placed on separate plasmids to reduce helper virus formation. Using a highly transfectable human cell line and sodium butyrate to further increase expression of each component, we achieved helper-free viral stocks of approximately 10(7) infectious units/ml by 48 h after transient co-transfection with the three plasmid components. This system can be used both for the generation of high titer retroviral stocks for transduction and for the rapid screening of a large number of MLV gag-pol or env mutants.

Induction of HIV-specific cytotoxic T lymphocytes in vivo with hybrid HIV-1 V3:Ty-virus-like particles.

In general, it has proven difficult to induce CTL responses using simple proteins or peptides without resorting to specialized adjuvants. In this study we show that particulate polymeric Ag in the form of hybrid Ty virus-like particles carrying the V3 region of HIV-1 gp120/160 envelope protein (V3:Ty-VLP) induce V3-specific CTL in BALB/c mice in the absence of adjuvant or lipid vehicle. In vitro restimulation of splenocytes with V3 peptide was necessary in order to generate effector CTL. Th cell activation was not required for this in vitro restimulation phase. The CTL induced by the V3:Ty-VLP were CD8+ve, H-2d-restricted, and HIV-1 isolate-specific (IIIB or MN). Co-administration of IIIB V3:Ty-VLP and MN V3:Ty-VLP primed both IIIB and MN V3-specific CTL. However, only IIIB V3-specific CTL were primed by hybrid Ty-VLP carrying IIIB, MN, and RF V3 loop sequences on the same particle indicating that there is intra- but not intermolecular competition between CTL epitopes. In direct comparisons, V3:Ty-VLP were substantially more potent than rgp120. Rgp160 and a 40mer IIIB V3 peptide both failed to prime V3-specific CTL. These data suggest that the particulate nature of hybrid Ty-VLP facilitates uptake into APC with subsequent access to the MHC class I processing pathway and that they may be useful vaccine vehicles for inducing cytolytic immunity against HIV-1 and other intracellular pathogens.

Hybrid human immunodeficiency virus Gag particles as an antigen carrier system: induction of cytotoxic T-cell and humoral responses by a Gag:V3 fusion.

In attempts to increase the immunogenicity of recombinant antigens, a number of particulate antigen presentation systems have been developed. In this study, we used human immunodeficiency virus Gag particles as carriers for the human immunodeficiency virus envelope V3 region. Gag:V3 fusion proteins were expressed from baculovirus expression vectors; they migrated to the insect cell membrane and budded from the cells as hybrid particles. An immunization study carried out with rats showed that the particles elicited a strong anti-Gag antibody response and a weak antibody response to the V3 region. A strong anti-V3 cytolytic T-cell response was elicited in immunized mice. These data show that retroviral Gag particles can be used as antigen presentation vehicles.

Pharmacokinetic data in the evaluation of the safety of food and color additives.

Safety evaluation of food and color additives intended for human use is usually based on toxicity data obtained from animal studies; human data are rarely available. The extrapolation of animal data to humans is often controversial. The important role that pharmacokinetic data could play in the safety evaluation of food and color additives is now widely recognized. This paper reviews the current scientific knowledge concerning the application of properly designed pharmacokinetic studies to the evaluation of the safety of food and color additives. In principle, pharmacokinetic data can be useful not only in designing, interpreting, and extrapolating animal toxicity studies to humans, but also in providing insight into the mechanisms of toxicity. Examples of such applications are provided.

Induction of high-titer neutralizing antibodies, using hybrid human immunodeficiency virus V3-Ty viruslike particles in a clinically relevant adjuvant.

The localization of neutralization determinants within the envelope glycoproteins of human immunodeficiency virus (HIV) has been largely achieved by immunizing small animals in conjunction with Freund's adjuvant. However, for eventual use in humans, candidate HIV vaccine components must also be efficacious in a nontoxic formulation. We describe here the production of hybrid Ty viruslike particles carrying the major neutralizing domain of HIV and demonstrate the induction of high-titer virus-neutralizing antibodies and an HIV-specific T-cell proliferative response after immunization in conjunction with aluminum hydroxide. As aluminum hydroxide and aluminum phosphate are the only adjuvants currently licensed for use in humans, these observations have implications for the development of an effective vaccine against HIV.

Inhibition of taurocholate efflux from rat hepatic canalicular membrane vesicles by glutathione disulfide.

In right-side out rat hepatic canalicular membrane vesicles glutathione disulfide (GSSG) inhibited the efflux of taurocholate approx. 70% in the presence or approx. 55% in the absence of a valinomycin-mediated K+ diffusion potential; maximal inhibition occurred at 5 mM GSSG. The inhibition by GSSG was abolished by dithioerythritol. Neither dithioerythritol alone nor GSH inhibited taurocholate efflux. S-(2,4-Dinitrophenyl)glutathione and N-ethylmaleimide showed intermediate inhibitory effects.