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M Farriol

Publications and source records attributed to M Farriol.

At least 37 records · Page 2Linked to original sources
PubMed1993

[The effect of sepsis on liver protein synthesis].

A study was made of the possible influence of sepsis on liver protein synthesis in septic and control rats, fed either parenterally (TPN) or with water and feed available "ad libitum". Liver protein synthesis was determined using the single massive dose method. In experiment I, the septic and control animals received TPN for twenty-four hours: in experiment II water and food was available to them "ad libitum". Twenty-four hours after the sepsis occurred, the animals were injected with a massive dose of 14C-labelled leucine, and slaughtered by decapitation. The septic animals with water and feed available "ad libitum" were fasted voluntarily without any intake. This group of fasted septic animals was the only one which lost weight. Liver protein synthesis increased in septic animals in comparison with the control animals, whether receiving TPN (112.2 +/- 8/78.5 +/- 13) or with "ad libitum" nutrition (97.2 +/- 15/60.8 +/- 8). The increased liver protein synthesis in the septic animals was modified (although with reduced significance) by parenteral nutrition (112.2 +/- 8/97.2 +/- 15). Our results suggest that sepsis increases liver protein synthesis, and that this protein synthesis may be enhanced by parenteral nutrition.

Animals↗
PubMed1993

Inhibition of visceral protein synthesis by certain amino acid supplements.

This study was focused on the effects produced by diets with different amino acid proportions on visceral protein synthesis (liver and jejunal mucosa). Eight groups of rats received an enteral modular diet supplemented with different amino acids (Group 1: Ile, Leu, Val; Group 2: Phe, Met, Gly; Group 3: Glu, Arg, Gly; Group 4: Gly, Group 5: Orn-Asp, Cys, Pro; Group 6: Lys, Ser, Thr; Group 7: Tyr, His, Ala). Group 8 was the control group. Rats were fed for four days. At the end of this period a flooding dose of 14C-Leu was injected and animals were killed. Liver and jejunal mucosa were removed and protein synthesis rate was determined. Results show a decreased liver protein synthesis in group fed with aromatic amino acids (53.8 +/- 8.4 vs. 88.6 +/- 12.1) and Glu-Arg (68.6 +/- 10.9). In jejunal mucosa there was a decrease of protein synthesis in groups fed with aromatic amino acids (98.7 +/- 16 vs 160.5 +/- 49). These changes seem to be related to the intracellular amino acid pool size and its influence on protein metabolism.

Amino Acids↗
PubMed1991

Effect of different MCT/LCT ratios on protein synthesis in injured rats fed parenterally.

The effect of the lipidic composition of the diet on the proteic synthesis of the male Sprague-Dawley rats fed parenterally for four days has been studied. All animals received identical nitrogen and caloric intake, but the ratio of medium to long-chain triglycerides (MCT/LCT) varied: group 1, control (0/100); group 2 (30/70); group 3 (50/50) and group 4 (70/30). Hepatic and jejunal protein synthesis were determined with L-(1-14C)-leucine. In groups 1, 3 and 4 muscle protein synthesis was measured with L-(3,4-3H)-phenylalanine. In liver, there were no significant differences in the fractional synthesis rate among the groups. In jejunum, the control group showed a higher fractional synthesis rate with statistically significant differences among the groups. In muscle, group 3 presented the highest fractional synthesis rate with statistically significant differences (p less than 0.05).

Animals↗
PubMed1990

Influence of fat emulsions in parenteral nutrition on visceral protein synthesis: study in hepatectomized rats.

The aim of this study was to evaluate the effect of total parenteral nutrition (TPN) with 100% long-chain triglyceride (LCT) (group A) and 50/50% medium/long-chain triglyceride (MCT/LCT) (group B) fat emulsions on visceral protein synthesis in 70% hepatectomized rats. The rats were fed TPN continuously for 7 days posthepatectomy. Protein synthesis was measured in the liver and jejunal mucosa with the flooding dose method. All rats received the same caloric and nitrogen intake, without statistically significant differences. The only difference between the two groups was the proportion of MCT to LCT in the diets. Hepatic and jejunal mucosa protein synthesis were significantly higher in group B, fed 50/50% MCT/LCT. These results suggest that fat emulsions with 50/50% MCT/LCT significantly enhance visceral protein synthesis after partial hepatectomy.

Animals↗
PubMed1987

Influence of the qualitative caloric composition of enteral diets on liver protein synthesis in normal and operated rats.

Protein synthesis L-(l-14C) leucine in liver was studied. Normal (n = 40) and operated (n = 40) Sprague-Dawley rats with an initial body weight of 161.18 +/- 12 g were divided into four groups (n = 10), respectively. Each group, subjected to the same conditions of temperature, light, noise and movement received a different commercial formula for human enteral nutrition and water for 8 days (normal rats) and six days (operated rats). All rats received the same caloric and protein intake per ml (l kcal; 6-7.10(-3) g protein), with no statistically significant differences among groups. The differences in diets were merely qualitative. The tolerance to all diets was similar, with rats attaining the expected weight. Losses of protein, alpha aminic nitrogen, total fat and non sterified fatty acid in faeces were negligible. In normal rats, different results in liver protein synthesis were obtained. No mass/synthesis rate correlation was found. Under these conditions it would appear that these results are due to the different diets used. In operated rats, a significantly different liver protein synthesis per gram of body weight was obtained, but not per gram of organ weight. These results suggest that the influence of the qualitative caloric intake, in the stress phase, is less than in the normal state.

Animals↗
PubMed1985

N tau-methylhistidine: inhibitor of hepatic protein synthesis?

Protein synthesis in isolated perfused rat livers has been studied. Aminoacids at physiological rat concentration (U-14C)-Leucine 0.065 muCi/ml and N Tau-Methylhistidine His (Tau-Me) were added to the perfusion medium. His (Tau-Me) from 0.01 to 2.0 mM causes a reduction between 40-60% in the rate of secreted proteins, independently of the His (Tau-Me) concentration.

Animals↗
PubMed1984

Valuation of protein metabolism and albumin in patients submitted to peripheral parenteral nutrition (PPN).

A protein breakdown study was carried out in ten post-operative patients, 24 hours after operation and after five days of peripheral parenteral nutrition; five of these patients were in a good nutritive condition (group A) and five were suffering from malnutrition and were critically ill (group B). Results indicate that the administration of amino-acids achieved a decrease in the degree of protein breakdown in the two groups under study, and also it was observed that better use was made of the nitrogen administered, particularly by the liver when the nitrogenous supply is completed with carbohydrates such as glucose. The difference obtained in values between the oxidized leucine and the leucine administered suggests that there is an endogenous donor pool, and the differences existing between breakdown and leucine oxidation values indicate that in group A, nourished solely with amino-acids, breakdown is lesser and oxidation greater than in group B, nourished with amino-acids and glucose, which suggests that there is more stimulation to re-use the amino-acids in this group.

Amino Acids↗
PubMed1983

Intralipid and free plasmatic tryptophan in vitro.

In an attempt to investigate the role of the lipidic emulsion Intralipid in the development of metabolic encephalopathy in a patient showing high free tryptophan levels, the relationship between lipidic emulsion and free tryptophan was examined in in vitro experiments. The addition of intralipid to normal serum produces an immediate increase in non-esterified fatty acids and a parallel rise in free tryptophan. Moreover, when serum with intralipid is incubated at 37 degrees C, the lipases release new non-esterified fatty acids and the free tryptophan increases proportionally. The non-esterified fatty acid content of intralipid was found to be 12 +/- 2 mEq X 1(-1). An inverse correlation was seen between free tryptophan and different serum albumin concentrations. It is concluded that intralipid causes an increase in free tryptophan levels. It is known that in vivo free tryptophan modulates 5-hydroxytryptamine synthesis and thus may be considered a possible causal agent for encephalopathy.

Bilirubin↗
PubMedDate not supplied

In vitro effects of melatonin on cell proliferation in a colon adenocarcinoma line.

The effect of melatonin on inhibition of cell growth was studied in CT-26, a murine colon carcinoma-derived cell line. Cells growing in exponential phase were exposed to low (10(-7)-10(-10) M) and high doses (1, 2 and 3 x 10(-3) M) of melatonin during 24 h. Synthesis of DNA was measured by 5-bromo-2'-deoxyuridine incorporation. There was no effect at low doses, but a statistically significant correlation was found between the decrease in DNA synthesis and the dose of melatonin used (r = -0.52, P < 0.001). This implied the following percentages of inhibition: 1 mM, 22%; 2 mM, 25%; 3 mM, 47%. Potential cell membrane damage by high doses of melatonin was investigated by lactate dehydrogenase measurement and no significant levels were observed. Analysis with a single saturation technique showed no detectable oestradiol receptors in this cell type; therefore, we can assume that the effects occurring with the addition of melatonin were not mediated by modulation of this hormone on oestrogen receptors. The decreases in cell growth were attributed to a moderate, but significant antiproliferative action of melatonin on this non-hormone-dependent cell line.

Adenocarcinoma↗
PubMedDate not supplied

Role of putrescine in cell proliferation in a colon carcinoma cell line.

OBJECTIVES: Putrescine, the precursor for higher polyamine biosynthesis, is necessary for cell growth in mammals. Ornithine decarboxylase (ODC) activity and polyamine production are increased in neoplastic cells. Using colon cancer cell line derived from a tumor with high metastatic potential (CT-26), our objective was to study the effect of exogenous putrescine on ODC regulation, polyamine metabolism, and cell proliferation. METHODS: Cells cultured with fetal calf serum were exposed to 100, 550, and 1000 microM putrescine for 24 h. RESULTS: Intracellular free putrescine, determined by high-performance liquid chromatography, showed a statistically significant increase in exposed cells compared with controls and a significant correlation with levels of the metabolite present in the medium (r = 0.93; P < 0.001). Bromodeoxyuridine incorporation into newly synthesized DNA, a marker of cell proliferation, showed a statistically significant increase in the three putrescine groups as opposed to the control group. In samples with added aminoguanidine, significant increases in DNA synthesis were observed in the 550- and 1000-microM putrescine groups as opposed to the control group. Spermidine and spermine intracellular contents in all three putrescine-treated groups remained below control levels. No statistical differences in ODC enzymatic activity or ODC mRNA content were observed. Newly incorporated putrescine stimulated colon tumor cell growth. CONCLUSIONS: Because neither enhanced conversion into the higher polyamines nor aminoguanidine inhibition of proliferation was observed, we suggest that this effect can be attributed to the putrescine molecule itself.

Adenocarcinoma↗
PubMedDate not supplied

[Importance of the polyamines: review of the literature].

The polyamines, putrescine, spermidine and spermine, are low-molecular weight substances, synthesized in eucariot cells from their immediate precursor, ornithine. These nitrogen compounds are essential for growth. The organism's endogenous supply is obtained through the diet or by synthesis in the intestinal flora. The polyamines are found in fruits and vegetables, foods of animal origin (milk, eggs, fish, and meat) and fermented food products (cheese, beer, and sauerkraut). Being nitrogenated compounds, they are considered as "minor" components of the diet. Ornithine decarboxylase, a short-half life enzyme, is the key to polyamine biosynthesis. Cellular polyamines are found in free or conjugated forms, the latter made possible, above all, by the presence of positive charges in their molecules. Their particular structure facilitates interaction with anions and binding to nuclear and membrane structures, particularly phospholipids, proteins and DNA. The organism's requirements for these substances are elevated during phases of intense growth or increased demand; thus, the nutritional supply can be crucial during the evolution of processes that involve a high degree of loss combined with deficits in endogenous biosynthesis. Increased tissue and organ polyamine concentrations correlate with diseases of neoplastic origin. It has been hypothesized that polyamine inhibition could be a therapeutic mechanism for such conditions. The supply of polyamines in artificial nutrition has not been measured and there are few data on the effects of artificial nutrition on circulating levels or the usual sites of storage in the body.

Diet↗
PubMedDate not supplied

[Polyamines in the gastrointestinal tract].

Polyamines are extremely important for cell growth, a fact that is reflected in the strict control of their synthesis and breakdown. In the small intestine, the polyamines play a fundamental role in all processes involving tissue regeneration, such as healing of stress-related ulcers, post-hepatectomy hepatic regeneration, adaptation syndrome after fasting and all processes with enterocyte hyperplasia or hypertrophy. In the gastrointestinal tract, there is a polyamine gradient in the villi-crypt cell axis and along the digestive tube, itself; the segments with greatest luminal content are the jejunum and the colon. Endogenous polyamine synthesis is stimulated by the diet and normal bacterial flora, which, in turn, regulate the amount and concentration of polyamines. Other hormonal and active peptide components (e.g. gastrin, epidermal growth factor, growth hormone) also have an influence on the pathway of polyamine synthesis. The interaction of these factors as related to the intestinal adaptive response is reviewed.

Animals↗
PubMedDate not supplied

Validation of an in vitro nutrition model using an enteral formula in aged neutrophils.

The aim of the study is to validate a cell culture model appropriate for assessing the effects of standard nutritional formulas on neutrophil functionality in vitro. The model consists of aged cells exposed to a commercial nutritional formula containing solely LCT as lipid component. Preliminary experiments determined dosage of formula and culture interval. Neutrophils were isolated from a pool of whole blood in healthy volunteers (18-55 years old) and cultured with and without addition of a commercial enteral diet with 3.5% lipids (equivalent to 0.04, 0.08, 0.2 and 0.4 mM of intraassay LCT) for 18, 42 or 76 hours. Based on cell viability results, doses of 0.2 and 0.4 mM LCT and culture time of 18 hours were established for subsequent experiments. Neutrophil functionality was evaluated by phagocytosis (NBT test), MDA production (lipoperoxidation index) and DNA fragmentation. Optic microscopy showed higher percentages of pre-apoptotic cells and a significant increase in DNA fragmentation as compared to controls only with an LCT concentration of 0.4 mM (p < 0.05). Interestingly, cell cultures with both 0.2 and 0.4 mM of added LCT showed significant decreases in malonyldialdehyde (MDA) release as a lipoperoxidation marker. This nutrition model of neutrophils and in vitro complete enteral commercial diet is relatively simply to execute and can be applied to different pathological conditions in which the aim is to study changes in neutrophil functionality.

Adolescent↗
PubMedDate not supplied

[Ingestion of antioxidants and polyamines in patients with severe burns].

Starting the first 24 hours after burn injury, energy supply, antioxidants and polyamines were assessed in 25 severe burn patients (20 men and 5 women) with a mean age of 45.6 +/- 20.4 years. Nutritional assessment was performed at 7, 15 and 21 days and was compared with a control group (n = 30). In 21 patients the burned body surface area was 20%-50% and in four patients it was greater than 50%. A mean decrease in energy supply of approximately 40% versus the calculated theoretical value was found in the three periods: 1,186 +/- 32; 1,117 +/- 589 and 1,331 +/- 578 kcal. In the first 15 days antioxidant ingestion was slightly lower than the recommended daily allowance for vitamin C: 60 mg versus 57 +/- 32, 57 +/- 53 and 75 +/- 53 mg, and was lower during the entire period for vitamin E: 10 mg versus 5.0 +/- 2.9; 4.5 +/- 3.0 and 5.3 +/- 3.4 mg; selenium: 40 microg versus 22.8 +/- 13.7; 22.5 +/- 9.8 and 25.7 +/- 11.2 microg and zinc: 12 mg versus 7.3 +/- 3.0, 6.8 +/- 4.8 and 8.4 +/- 5.3 mg. Taurine ingestion decreased on day 15 and significantly increased on day 21: 65.7 +/- 30 mg, 50.9 +/- 25 and 72.0 +/- 29 mg (p < 0.05). Ingestion of total polyamines did not differ significantly from the values observed in the control group and were as follows: day 7, total 45.2 +/- 23.0 umol, putrescine 16.7 +/- 10.2, spermidine 13.5 +/- 7.6 and spermine 13.6 +/- 8.8; day 15: total 41.1 +/- 38.5 and 14.9 +/- 4.0, 11.7 +/- 9.4 and 10.89 +/- 9.0; day 21: total 39.1 +/- 35.3 and 15.4 +/- 16.9, 12.3 +/- 11.4 and 17.3 +/- 16.8 umol, respectively.

Antioxidants↗