The possible protective role of exogenous SA and NO donor (sodium nitroprusside) against salt stress was examined NaCl-induced oxidative stress in <i>Glycine max</i> L. The results indicated that NaCl-induced ionic toxicity led to significant increase of Na⁺ uptake in root and shoot of soybean, while K⁺ and Ca²⁺ uptake was decreased markedly. Application of SA, SNP and the combination of SA with SNP inhibited Na+ uptake, but improved K⁺ and Ca²⁺ uptake. Under NaCl salinity, germination percentage (GP) was decreased significantly as compared with control plants. Moreover, the activity of lipoxygenase (LOX) was increased by NaCl, while the application of SA, NO and SA + SNP could decrease LOX activity in this condition. As well, activities of the polyphenol oxidase (PPO) and phenylalanine ammonia lyase (PAL) were significantly decreased by 100 mM NaCl, while the application of exogenous SA and NO increased the activities of PPO and PAL. In addition, it was observed that the SA and NO have effective functions in decreasing the damages induced by NaCl salinity. The seeds of G. <i>max</i> cv. Union × Elf (called L17) were obtained from the Institute of Sapling and Seed in Tehran and experiments have been done in Science and Research Branch, Islamic Azad University. After treatment with SA, SNP and NaCl, the plants were harvested for the estimation of ionic contents and assay of enzyme activities. The results showed that SA and NO act synergistically to reduce the damaging effects of salt tress via enhancing the activity of antioxidative systems

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The results validate the OC-Clamp method to monitor the posthepatic appearance of glucose after carbohydrate ingestion and to discriminate between different carbohydrate sources. The results suggest that the technique be used in humans.

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Intestinal transport of nutrients coincides with their partial catabolism in the gut. The aim of the present study was to measure intestinal oxygen consumption and nutrient metabolism after a meal or during a short fast. Nutrient and oxygen balances across the small intestine were measured in conscious 50 kg (live wt) pigs. Jejunal enterocytes were also isolated from 1-hr postprandial, postabsorptive, or 3-day fasted pigs, in order to evaluate their capacities to metabolize 5 mM glucose and 2 mM glutamine. Whatever the nutritional state, intestinal oxygen consumption was high, since 26 +/- 2% (n = 6) of the oxygen arterial supply was extracted by the small intestine. Furthermore, the consumption of a mixed meal induced a rapid and transient rise in oxygen consumption. In the postabsorptive state, the intestinal uptake of glucose (0.31 +/- 0.08 mmole/min, n = 6) was twice higher than that of glutamine. The role of glucose as a fuel was also evidenced after a 3-day fast. During nutrient absorption, glutamine was highly utilized, and lactate was produced. The capacity of enterocytes isolated from fed pigs to metabolize glucose was dramatically reduced, as was 6-phosphofructo 1-kinase activity. In contrast, intestinal muscle presented a high glycolytic capacity from glucose, suggesting that the main site of intestinal lactate production during nutrient absorption would be the muscular rather than the epithelial layer.

Gamma-Aminobutyric acid (GABA) accumulates in plants following exposure to heavy metals. to investigate the role of GABA in cadmium (cd) tolerance and elucidate the underlying mechanisms, GABA (0, 25 and 50 µM) was applied to cd-treated maize plants. Vegetative growth parameters were improved in both cd-treated and control plants due to GABA application. cd uptake and translocation were considerably inhibited by GABA. Antioxidant enzyme activity was enhanced in plants subjected to cd. concurrently GABA caused further increases in catalase and superoxide dismutase activities, which led to a significant reduction in hydrogen peroxide, superoxide anion and malondealdehyde contents under stress conditions. polyamine biosynthesis-responsive genes, namely ornithine decarboxylase and spermidine synthase, were induced by GABA in plants grown under cd shock. GABA suppressed polyamine oxidase, a gene related to polyamine catabolism, when plants were exposed to Cd. Consequently, different forms of polyamines were elevated in Cd-exposed plants following GABA application. The maximum quantum efficiency of photosystem II (F v /f m) was decreased by cd-exposed plants, but was completely restored by GABA to the same value in the control. these results suggest a multifaceted contribution of GABA, through regulation of cd uptake, production of reactive oxygen species and polyamine metabolism, in response to cd stress. Heavy metal (HM) toxicity is considered a major threat to living organisms. HM-polluted soils derived from increasing geologic and anthropogenic activities have significantly impacted the production of high-quality agricultural crops in certain regions of the world. Plants growing on these soils exhibit reduced growth, photosynthetic performance, and yield 1. As a naturally occurring HM pollutant, Cd exposure has been documented in most organisms, particularly plants and humans 2. World fertilizer consumption is increasing and will eventually reach a point where the drawbacks outweigh the benefits 3. The same mechanisms that drive improved plant productivity often create side effects such as environmental contamination. Furthermore, some components of fertilizers, especially Cd, accumulate in both body and food chain, where they remain for an extended period and causes adverse health effects 4. Therefore, fertilizers containing very high levels of Cd (417 mg/kg) threaten human health by accumulation in important crop such as maize 5. Maize, as one of the most popular cereal grain, is widely cultivated across the world. Maize is also produced at an industrial scale as a key input in various products such as syrups, soft drinks and charcoals 6,7. Therefore, there is a strong incentive to minimize the toxic effects of Cd in maize.

-We have investigated the possible effects of algal polysaccharides on postprandial blood glucose and insulin responses in an animal model, the pig. Three seaweed fibres of different viscosities, extracted from Palmaria palmata (PP), Eucheuma cottonii (EC), or Laminaria digitata (LD), were compared to purified cellulose (CEL). Blood glucose and plasma insulin levels were monitored and intestinal absorption quantified for 8 h following a high carbohydrate test-meal supplemented with 5% fibre. Digestive contents were also sampled, 5 h postprandial. As compared to CEL, PP had no effect on glucose and insulin responses. The latter decreased with EC, but glucose absorption balance was not modified. LD addition resulted in a dramatically reduced glucose absorption balance, accompanied by a higher amount of starch left in the small intestine. Among polysaccharides tested, only the highly viscous alginates could affect intestinal absorption of glucose and insulin response. seaweed / non-starch polysaccharides / intestinal absorption / glucoseRésumé -Les fibres alimentaires extraites d'algues peuvent moduler l'absorption intestinale du glucose et la réponse insulinique chez le porc. L'effet des fibres algales sur la réponse glycémique et insulinique a été étudié chez un modèle animal, le porc. Des fibres de viscosité différente, extraites de Palmaria palmata (PP), Eucheuma cottonii (EC), ou Laminaria digitata (LD), ont été comparées à de la cellulose purifiée (CEL). La glycémie et l'insulinémie plasmatique, ainsi que l'absorption intestinale du glucose ont été suivies 8 h après un repas-test hyperglucidique additionné de 5 % de fibres. Des contenus digestifs ont aussi été prélevés 5 h après le repas. L'addition de PP n'a pas modifié les réponses glycémique et insulinique par rapport à CEL. Elles étaient diminuées par l'addition Reprod. Nutr. Dev. 40 (2000) 33-47 33