Plant-based diets and their effects on the metabolism and survival of chronic renal patients undergoing conservative treatment

Diet therapy in conservative treatment of chronic kidney disease involves protein restriction, but there is not enough evidence to recommend a particular type of protein, whether animal or plant based. However, studies suggest that plant-based diets help reduce the consumption of total and animal protein, reduce the need for nephroprotective drugs, improve complications and bring advantages in terms of disease progression and patient survival. The article considers up-to-date data on the effects of this diet and observed that when low in protein, primarily vegetable and in some cases supplemented with ketoanalogues, it can result in positive clinical outcomes, such as: delay in the decrease in the glomerular filtration rate, lower concentrations of urea, reduction of serum creatinine and phosphorus concentrations, lower metabolic acidosis, higher insulin sensitivity and lower systemic inflammation. As a whole, this dietary pattern may be able to postpone the start of dialysis with less progression of renal insufficiency. Additional research is needed to better characterize this dietary pattern.

La dietoterapia en el tratamiento conservador de la enfermedad renal crónica implica la restricción de proteínas, pero aún no hay pruebas suficientes para recomendar un tipo concreto de proteínas, ya sean animales o vegetales. Sin embargo, los estudios sugieren que las dietas basadas en plantas ayudan a reducir la ingesta de proteínas totales y animales, disminuyen la necesidad de fármacos nefroprotectores, mejoran las complicaciones y presentan ventajas con respecto a la progresión de la enfermedad y la supervivencia de los pacientes. En este artículo se consideran datos actualizados sobre los efectos de esta dieta y se observa que, cuando es hipoproteica, principalmente vegetal y en algunos casos se complementa con cetoanálogos, puede dar lugar a resultados clínicos positivos, como una disminución retardada de la tasa de filtración glomerular, concentraciones más bajas de urea, concentraciones reducidas de creatinina y fósforo séricos, menor acidosis metabólica, mayor sensibilidad a la insulina y menor inflamación sistémica. En conjunto, este patrón dietético tiene el potencial de retrasar el inicio de la diálisis con una menor progresión de la insuficiencia renal. Es necesario seguir investigando para caracterizar mejor este patrón dietético.

Effect of Microbial Phytase on Nutrient Availability and Growth of Juvenile Clarias gariepinus Fed Soyabean and Groundnut-based Diets

Several studies have shown the positive effect of phytase on phosphorus utilization by fish and animals, with the use of phytase sources determined for different fish species. Few studies have tested phytase response to different diets, which may affect nutrient availability for optimum growth due to differences in phytate location. The research, therefore, studied the effect of phytase to diets based on soya bean and groundnut meal for Clarias gariepinus on nutrient availability and growth. In trial 1, four groups of soya bean S1, S2, S3 and S4 replaced fish meal at 25%, 50%, 75% and 100% and supplemented with 250, 500, 750 and 1000 FTU/g phytase, respectively. In trial 2, four groups of groundnut meal diet G1, G2, G3, G4, G5 and G6, were similarly supplemented with the same phytase levels used in experiment 1. Fish meal control (S0=G0) was not supplemented with phytase. Result showed that 250 FTU/g phytase showed the highest mean weight gain for both plants. In conclusion, the research has shown that the chemical nature of phytate, rather than its concentration and location, may influence the utilization of phosphorus for optimum growth in the fish by supplementing 250 FTU/g, with a range of available phosphorus requirement of between 0.75% (Y = 0.363 + 4.155X - 2.772X2, R2 = 0.759) and 0.80% (Y = 0.307 + 3.303X - 2.059X2, R2= 0.210)

Criteria for Safe Use of Plant Ingredients in Diets for Aquacultured Fish

The Norwegian Food Safety Authority (Mattilsynet) asked the Norwegian Scientific Committee for Food Safety (Vitenskapskomiteen for mattrygghet) to assess if the criteria for safe use of plant ingredients in diets for aquacultured fish fulfil the Feed regulative §7 to “not induce negative health effects in the animal”, and in this context aquacultured fish. The use of feed ingredients of both plant and animal origin is set by the regulation “Forskrift 7. November 2002 nr 1290”, and amendments. The objective of the regulation is to protect animals, consumers and the environment. For animals, the feed shall not pose a risk, or danger, to their health. Aspects to be assessed were whether the changes in fish diet ingredient composition seen in recent years with high levels of plant ingredients, plus additions of immunostimulants, would in any manner challenge fish health and if any ingredient should be limited due to its negative effect, or induce any long-term negative effect. “Long-term” here extends beyond normal production time for consumption, e.g. when substances that might affect fish health are included in broodstock diets. Atlantic salmon (Salmo salar), rainbow trout (Onchorhyncus mykiss), Atlantic halibut (Hippoglossus hippoglossus) and Atlantic cod (Gadus morhua) should especially be addressed. However, since all life stages should be included, especially broodstock, and also possible long-term effects, and literature on these for the requested species is scarce, the assessment mentions studies on other species when relevant. With the exception of full-fat and extracted soybean meal for salmonids, substituting at least part of the fishmeal fraction of aquafeeds with individual plant ingredients is promising, at least in the short to medium term. Indeed in some cases, diets containing up to 20% inclusion level of high-quality plant protein sources have resulted in better nutrient digestibility and growth parameters than the fishmeal-based control diets. When substituting fishmeal with plant ingredients, however, it is necessary to balance the diets regarding limiting amino acids and minerals. Adding plant proteins to fish diets result in the introduction of anti-nutritional factors. There is an urgent need to investigate consequences of various anti-nutritional factors, individually and in combinations, to nutrient digestibility, utilization and metabolism as well as to intestinal function, structure, defence mechanisms and microbiota. Long-term effects also merit investigation. This will aid in the ability to predict how a newly introduced plant ingredient as well as combinations of plant ingredients may affect the fish and identify steps needed to avoid adverse health effects. As many of the potential disadvantages of using plant oils in salmonid diets are related to either very high levels of n-6 PUFA (most available oils) or very high levels of linseed oil, it would be recommended that mixtures of plant oils should be used as feed inclusions. By adjusting the ratio of n-6 and n-3 the level of eicosanoids can be controlled. By including palm oil, potential problems in lipid digestibility and transport can be controlled. A standard inclusion of soybean lecithin may also be advisory. These and other variants of mixtures of oil sources have been explored in recent years with some success in salmonid fish. Such mixtures do not seem to be necessary for marine fish. Modern finfish aquaculture faces problems such as bone and skeletal deformities, cataracts, heart disorders, unspecific ulceration and various digestive disorders including intestinal colic in Atlantic cod, gastric dilatation (bloat) in rainbow trout, and intestinal tumours, at low incidence, in Atlantic salmon broodstock. Most of the mentioned problems have been related to malnutrition, feed, intensive growth and/or unfavourable environmental conditions. The disorders are often not lethal, but may imply a fish welfare problem and increase the susceptibility to secondary disorders and infectious diseases. Major changes in feed composition and feed ingredients may increase the risk for such production-related disorders in intensive fish farming. Care should be taken when choosing plant alternatives, both types and qualities, to prevent nutrition-related diseases such as skeletal deformities, cataracts, heart conditions, and other, unspecific symptoms. The change from marine- to plant-based diet ingredients, results in changed profile and content of undesirable substances. The list of undesirable substances included in the feed legislation is, in general, sufficient, but it should be considered to include pesticides in use today and more of the mycotoxins. Currently only aflatoxin B1 is included, while only recommendations exist for other mycotoxins. Studies of dietary exposure to undesirable substances, e.g. pesticides and mycotoxins, and their toxic effects and toxicokinetics in fish are scarce. To date, the application of pre- and probiotics for the improvement of aquatic environmental quality and for disease control in aquaculture seems promising; however, the information is limited and sometimes contradictory. Currently there are numerous gaps in existing knowledge about exogenous nucleotide application to fish including various aspects of digestion, absorption, metabolism, and influences on various physiological responses, especially expression of immunogenes and modulation of immunoglobulin production. As limited information is available about the effect of immunostimulants, prebiotics and nucleotides on gut morphology, this topic should be given high priority in future studies. Heat processing of raw materials and of the complete fish diets may potentially alter nutritional properties of plant materials. However, the negative effects appear to be modest under practical conditions.

Anthelmintic activity of Leucaena leucocephala protein extracts on Haemonchus contortus / Atividade anti-helmíntica de extratos proteicos de Leucaena leucocephala sobre Haemonchus contortus

Abstract The objective of this study was to evaluate the effects of protein extracts obtained from the plant Leucaena leucocephala on the nematode parasite Haemonchus contortus. The seeds, shell and cotyledon of L. leucocephala were separated and their proteins extracted using a sodium phosphate buffer, and named as TE (total seed extract), SE (shell extract) and CE (cotyledon extract). Soluble protein content, protease, protease inhibitory and chitinase activity assays were performed. Exsheathment inhibition of H. contortus larvae were performed at concentrations of 0.6 mg mL–1, and egg hatch assays were conducted at protein concentrations of 0.8, 0.4, 0.2, 0.1 and 0.05 mg mL–1. The effective concentration for 50% hatching inhibition (EC50) was estimated by probit. Different proportions of soluble proteins, protease and chitinase were found in TE and CE. Protease inhibitory activity was detected in all extracts. The EC50 of the CE and TE extracts were 0.48 and 0.33 mg mL–1, respectively. No ovicidal effects on H. contortus were detected in SE extracts, and none of the protein extracts demonstrated larvicidal effects on H. contortus. We therefore conclude that protein extracts of L. leucocephala had a detrimental effect on nematode eggs, which can be correlated with the high protease and chitinase activity of these extracts.

Resumo O objetivo deste estudo foi avaliar a atividade anti-helmíntica de extratos proteicos de leucena (Leucaena leucocephala) sobre Haemonchus contortus. As sementes, as cascas e os cotilédones foram moídos separadamente e as proteínas extraídas com tampão fosfato de sódio e denominados: TE (extrato total), SE (extrato casca) e CE (extrato cotilédone). O teor de proteínas, atividade proteolítica, inibitória de protease e quitinolítica dos extratos foram verificados, além da ação sobre a eclosão de ovos e desembainhamento larvar de H. contortus. A concentração efetiva para inibição de 50% da eclosão dos ovos (EC50) foi calculada através do probit. Foi demonstrado que TE e CE possuem, em diferentes proporções, proteínas solúveis, protease e quitinase. Atividade inibitória de protease foi encontrada em todos os extratos. A EC50 dos extratos CE e TE foram 0,48 e 0,33 mg de proteína mL–1, respectivamente. O extrato SE não apresentou atividade sobre a eclosão dos ovos. Os extratos proteicos não apresentaram efeito larvicida sobre H. contortus. Conclui-se que a ação de extratos proteicos de L. leucocephala afetam negativamente a eclodibilidade dos ovos, correlacionando-se com a alta atividade de protease e quitinase dos extratos testados.

IN VITRO EVALUATION ON THE EFFECTS OF PLANT PROTEIN MAP30 AGAINST HUMAN IMMUNODEFICIENCY VIRUS TYPE 1 / 解放军医学杂志

To evaluate the inhibitive effect of plant protein MAP30 (momordica anti-HIV protein of 30kDa), AZT (3′-azido-2′,3′-dideoxythymidine) , ACV (acyclovir) and IFN-?2a (interferon-?2a) against HIV-1 in vitro, MT4 was used as the target cell and the inhibitive effects of these drugs on HIV-1 P24 expression were investigated by ELISA. The inhibitory effect of these drugs on HIV-1-induced cytopathy was also evaluated. The 50% inhibition concentration (IC 50) of MAP30 was 0.9?mol/L. In comparison, the IC 50 for AZT , a commonly used anti-HIV drug, was 0.7?mol/L. The cytopathic effect induced by HIV-1 was also inhibited by MAP30 and AZT. ACV and IFN-?2a showed little effect on HIV-1. All these results strongly indicated that plant protein MAP30 could obviously inhibit HIV-1 replication in vitro.