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At least 127 records · Page 7Linked to original sources
PubMed1996

Digestibilities of energy, protein, fat and nonstarch polysaccharides in a low fiber diet and diets containing coarse or fine whole meal rye are comparable in rats and humans.

The apparent digestibility of energy, protein, fat and nonstarch polysaccharides (NSP) of a low fiber diet and two high fiber diets containing coarse or fine whole meal rye bread was studied in experiments with humans and rats. Human subjects consumed the experimental diets for 3 wk each in a 3 x 3 cross over design. For the rat diets, duplicate portions of the foods consumed by the human subjects were mixed together, freeze dried and ground. There was a good agreement in the digestibility of energy (humans: 94.7 +/- 0.9, 91.2 +/- 1.2 and 91.6 +/- 1.4%; rats: 95.0 +/- 0.8, 92.5 +/- 1.4 and 91.7 +/- 1.8%) and fat (humans: 95.2 +/- 1.5, 94.4 +/- 1.0 and 94.8 +/- 2.5%, rats: 95.4 +/- 0.9, 94.0 +/- 0.4 and 94.0 +/- 0.4%) for the low fiber diet and the diets containing coarse or fine whole meal bread, respectively. Apparent and true digestibility of protein was consistently lower (P < 0.0001) in humans (apparent digestibility: 90.6 +/- 1.5, 86.2 +/- 1.4 and 86.3 +/- 2.3%; true digestibility: 95.1 +/- 1.5, 90.7 +/- 1.4 and 90.8 +/- 2.2%) than in rats (apparent digestibility: 92.3 +/- 1.1, 89.4 +/- 0.9 and 88.9 +/- 1.0%; true digestibility: 98.3 +/- 1.1, 94.9 +/- 0.9 and 94.2 +/- 1.0%) for all three diets. The digestibility of NSP tended to be lower (P < 0.066) in rats than in humans for the diet containing fine whole meal bread (rats: 59.6 +/- 8.0%, humans: 68.0 +/- 5.2%) and the low fiber diet (rats: 72.1 +/- 10.8%; humans: 80.5 +/- 7.1%), whereas it was similar in both species for the diet containing the coarse whole meal bread (rats: 66.1 +/- 6.0%; humans: 65.8 +/- 9.3%). In spite of some differences in digestibility values, our results suggest that the rat is a suitable model for humans to predict digestibility of nutrients in mixed diets containing cereal fiber sources.

Adult↗
PubMed1999

Western-type diets induce insulin resistance and hyperinsulinemia in LDL receptor-deficient mice but do not increase aortic atherosclerosis compared with normoinsulinemic mice in which similar plasma cholesterol levels are achieved by a fructose-rich diet.

The role of insulin resistance (IR) in atherogenesis is poorly understood, in part because of a lack of appropriate animal models. We assumed that fructose-fed LDL receptor-deficient (LDLR-/-) mice might be a model of IR and atherosclerosis because (1) fructose feeding induces hyperinsulinemia and IR in rats; (2) a preliminary experiment showed that fructose feeding markedly increases plasma cholesterol levels in LDLR-/- mice; and (3) hypercholesterolemic LDLR-/- mice develop extensive atherosclerosis. To test whether IR could be induced in LDLR-/- mice, 3 groups of male mice were fed a fructose-rich diet (60% of total calories; n=16), a fat-enriched (Western) diet intended to yield the same plasma cholesterol levels (n=18), or regular chow (n=7) for approximately 5.5 months. The average cholesterol levels of both hypercholesterolemic groups were similar (849+/-268 versus 964+/-234 mg/dL) and much higher than in the chow-fed group (249+/-21 mg/dL). Final body weights in the Western diet group were higher (39+/-6.2 g) than in the fructose- (27.8+/-2.7 g) or chow-fed (26.7+/-3.8 g) groups. Contrary to expectation, IR was induced in mice fed the Western diet, but not in fructose-fed mice. The Western diet group had higher average glucose levels (187+/-16 versus 159+/-12 mg/dL) and 4.5-fold higher plasma insulin levels. Surprisingly, the non-insulin-resistant, fructose-fed mice had significantly more atherosclerosis than the insulin-resistant mice fed Western diet (11.8+/-2.9% versus 7.8+/-2. 5% of aortic surface; P<0.01). These results suggest that (1) fructose-enriched diets do not induce IR in LDLR-/- mice; (2) the Western diets commonly used in LDLR-/- mice may not only induce atherosclerosis, but also IR, potentially complicating the interpretation of results; and (3) IR and hyperinsulinemia do not enhance atherosclerosis in LDLR-/- mice, at least under conditions of very high plasma cholesterol levels. The fact that various levels of hypercholesterolemia can be induced in LDLR-/- mice by fat-enriched diets and that such diets induce IR and hyperinsulinemia suggest that LDLR-/- mice may be used as models to elucidate the effect of IR on atherosclerosis, eg, by feeding them Western diets with or without insulin-sensitizing agents.

Animals↗
PubMed1997

Comparison of a carbohydrate-rich diet and diets rich in stearic or palmitic acid in NIDDM patients. Effects on lipids, glycemic control, and diurnal blood pressure.

OBJECTIVE: To compare the effects on lipid levels, glycemic control, and diurnal blood pressure of two diets rich in one of the two quantitatively most important saturated fatty acids, stearic and palmitic acid, with a carbohydrate-rich diet in NIDDM patients. RESEARCH DESIGN AND METHODS: A total of 15 NIDDM patients participated in a randomized crossover study with three 3-week diet interventions separated by 2-week washout periods. Patients started with a diet rich in stearic acid (44 E% [percent of total energy] fat [13 E% stearic acid], 40 E% carbohydrate, 15 E% protein), palmitic acid (45 E% fat [16 E% palmitic acid], 40 E% carbohydrate, 15 E% protein), or carbohydrate (29 E% fat, 51 E% carbohydrate, and 18 E% protein), then were shifted to the other two diets in a randomized block design. At the start and end of each intervention period, fasting blood samples were drawn for analysis of lipids and blood glucose. In addition, diurnal blood pressure was measured. RESULTS: At the end of the 3-week interventions, total cholesterol was significantly higher after the palmitic acid-rich diet than after the stearic acid-rich or carbohydrate-rich diets (5.3 +/- 1.3 vs. 5.0 +/- 1.2 and 4.9 +/- 1.2 mmol/l, respectively; P = 0.03). No significant differences in triglyceride, LDL, or HDL cholesterol levels were seen after the three intervention diets. No difference in effects between the diet periods were seen for fructosamine, HbA1c, fasting blood glucose, or diurnal blood pressure. CONCLUSIONS: For the first time, it has been demonstrated that a diet rich in palmitic acid was not as effective in lowering cholesterol levels as carbohydrate-rich and stearic acid-rich diets in NIDDM patients. No deleterious effects were seen on diurnal blood pressure, triglyceride levels, and glycemic control. Development of foods containing stearic acid rather than the more atherogenic saturated fatty acids may allow a wider choice of acceptable foods to NIDDM patients.

Adult↗
PubMed1994

Diet preference and meal patterns of weanling pigs offered diets containing either spray-dried porcine plasma or dried skim milk.

Preference tests and meal pattern analyses were conducted to examine the feed intake response of weanling pigs to spray-dried porcine plasma (SDPP). In Exp. 1, 36 weanling pigs (mean +/- SD; 6.2 +/- .8 kg and 26 d of age) were allowed to choose between a SDPP diet (8.5% SDPP, 20% dried whey, 10% lactose, and .13% DL-methionine) and a dried skim milk (DSM) diet (20% each of DSM and dried whey) throughout 21 d postweaning. Twenty-eight pigs preferred the SDPP diet and seven pigs preferred the DSM diet. Preference for SDPP became apparent by d 2 (60% of total feed consumption) and increased (P < .01) to d 21 (71% of total feed consumption). Average daily feed consumption was 371 and 172 g for the SDPP and DSM diets, respectively (P < .01). The meal patterns of 16 weanling pigs (mean +/- SD; 7.2 +/- .3 kg and 26 d of age) offered either the SDPP or the DSM diet were examined in Exp. 2. On d 3, 7, and 14 postweaning, feeding behavior was observed continuously for 18 h (0600 to 2400). Time spent consuming feed and time between periods of feeding were recorded. Although the difference was not significant, pigs fed the SDPP diet consumed 27 and 6% (P = .38) more feed than pigs fed the DSM diet during the first 7 d and during the entire 21-d period, respectively. This difference was reflected in increased (P < .05) rate of feed consumption on d 3 and 7. Diet had no effect (P > .10) on meal size, the number of meals, or the percentage of time spent consuming feed. Weanling pigs prefer diets containing SDPP to those containing DSM, and the increased consumption of diets containing SDPP may be due to greater palatability.

Analysis of Variance↗
PubMed2002

Effects of a high olive oil diet on the clinical behavior and histopathological features of rat DMBA-induced mammary tumors compared with a high corn oil diet.

Effects of a high virgin olive oil diet on the promotion stage of dimethylbenz(alpha)anthracene-induced mammary carcinogenesis in rats were investigated in comparison with those of a high corn oil diet. Animals were randomly placed into 4 groups: control, fed a normolipidic control diet (3% corn oil); M, fed a high corn oil diet (20%); O, fed a high olive oil diet (3% corn oil plus 17% olive oil); and MO, fed the high olive oil diet after 33 days of high corn oil diet. Whereas the high corn oil diet clearly stimulated the mammary carcinogenesis, reducing the latency time and increasing the tumor incidence, multiplicity and volume, the high olive oil diet led to a lower tumor incidence than in the former group, a latency time similar to that of the control and lower tumor multiplicity and volume even than in the control group. Moreover, the histopathological features of the adenocarcinomas in olive oil groups were compatible with a greater degree of differentiation. These data suggest that the high virgin olive oil diet would have acted as a negative modulator of the experimental mammary carcinogenesis conferring to the tumors a more benign clinical behavior and a lower histopathological malignancy in comparison with the control and high corn oil diets.

9,10-Dimethyl-1,2-benzanthracene↗
PubMedDate not supplied

[Comparison between a diet with mainly vegetal protein content and a diet with mainly animal protein content in hepatic cirrhosis].

Eight cirrhotic patients were studied in a randomized crossover single blind study in order to compare the effects of two isocaloric, and with equal amount of protein diets on nitrogen balance and on the portal systemic index. One diet was 2:3 vegetable protein to total protein content (diet V) and the other 2:3 animal protein to total protein content (diet A). Each diet was changed every three weeks. Five patients followed the VAV scheme and three the AVA scheme. The mean values of the porto systemic index were almost the same with the two diets while the value of the nitrogen balance was less negative with the diet A than with the diet V, showing an increasing trend, more marked with the diet A, at every consecutive time of observation. The variance analysis was not significant for any of the two diets. Diet V was well tolerated.

Aged↗
PubMed1992

The effect of a shift from a mixed diet to a lacto-vegetarian diet on human urinary and fecal mutagenic activity.

This is an investigation of the effects of a shift from a well-balanced mixed diet to a lacto-vegetarian diet on the mutagenic activity in urine and feces. The participants were 20 normal-weight, non-smoking subjects (4 men and 16 women, mean age 44 years, range 27-61 years). The fecal samples were assayed for direct-acting mutagens with the fluctuation test for weak mutagens and the urinary samples were assayed with the same assay but with a metabolic activation system, a so-called S9 fraction. The switch from a mixed diet to a lacto-vegetarian diet was not a shift from a so-called high to a low risk diet for colon cancer but rather from a 'medium high risk diet' to a 'low risk diet', even though there were significant changes in nutrients and food components between the two diets. There was a decrease in fat (P = 0.009) and protein intake (P = 0.04) and an increase in total carbohydrate (P = 0.001), fiber (P = 0.001), calcium (P = 0.006) and vitamin C intake (P = 0.019). Among the food preparation methods the use of frying decreased (P = 0.02) and the habit of eating a new vegetable meal increased (P = 0.05). Three months after the dietary shift the concentration of fecal direct-acting mutagens decreased significantly (P less than 0.05), though the total mutagenic activity excreted in feces per 24 h was not different between the two diet periods. Both the concentration and the total amount of promutagens in the urine were decreased after 3 months on the lacto-vegetarian diet. The decrease in fecal mutagenic activity might be explained by a higher fiber intake, which leads to higher water content in feces and thereby a dilution of fecal mutagenic compounds.

Adult↗
PubMed2004

Long-term effects of advice to consume a high-protein, low-fat diet, rather than a conventional weight-loss diet, in obese adults with type 2 diabetes: one-year follow-up of a randomised trial.

AIMS/HYPOTHESIS: This study compared the long-term weight loss and health outcomes at 1-year follow-up, after a 12-week intensive intervention consisting of two low-fat, weight-loss diets, which differed in protein content. METHODS: We randomly assigned 66 obese patients (BMI: 27-40 kg/m2) with type 2 diabetes to either a low-protein (15% protein, 55% carbohydrate) or high-protein diet (30% protein, 40% carbohydrate) for 8 weeks of energy restriction (approximately 6.7 MJ/day) and 4 weeks of energy balance. Subjects were asked to maintain the same dietary pattern for a further 12 months of follow-up. RESULTS: The study was completed by 38 of the subjects, with equal dropouts in each group. At Week 64, weight reductions against baseline were -2.2+/-1.1 kg (low protein) and -3.7+/-1.0 kg (high protein), p<0.01, with no diet effect. Fat mass was not different from baseline in either group. At Week 12, both diets reduced systolic and diastolic blood pressure by 6 and 3 mm Hg respectively, but blood pressure increased more with weight regain during follow-up in the low-protein group (p< or =0.04). At Week 64, both diets significantly increased HDL cholesterol and lowered C-reactive protein concentrations. There was no difference in the urinary urea : creatinine ratio at baseline between the two groups, but this ratio increased at Week 12 (in the high-protein group only, p<0.001, diet effect), remaining stable during follow-up in both diets. CONCLUSIONS/INTERPRETATION: A high-protein weight-reduction diet may in the long term have a more favourable cardiovascular risk profile than a low-protein diet with similar weight reduction in people with type 2 diabetes.

Adipose Tissue↗
PubMed1994

Morphological studies of hypomineralized enamel of rat pups on calcium-deficient diet, and of its changes after return to normal diet.

BACKGROUND: Micro-hardness investigations have shown that rat pups nursed by mothers on a low calcium diet and weaned with the maternal calcium-deficient diet develop hypomineralized enamel. The inorganic and organic components of this enamel, their relationships, and their changes after return to normal diet have been studied by light and electron microscopy. METHODS: The maturation zone of incisor enamel has been studied in: (1) rats nursed for 20 days by mothers on a low calcium diet and weaned for 30 days with the same diet (E1 enamel); (2) rats that after the calcium-deficient diet were fed normal diet for 10 days (E2 enamel); and (3) rats nursed for 20 days by mothers on a normal diet and weaned for 30 days with a normal diet (controls). RESULTS: The results showed that E1 enamel was hypomineralized, as noted by its Azure II-Methylene blue stainability in undecalcified sections, its light staining with the von Kossa method, and its ultrastructure. E1 crystallites, although present throughout the whole enamel, were thinner than those of E2 enamel, which were similar to those of controls. E1 interrod crystallites were thicker in the intermediate than in the dentinal zone and were thicker than rod crystallites. Organic matrix was present throughout the whole E1 enamel. Its organic components (crystal ghosts) had the same shape, arrangement, and organization as those of inorganic crystallites. Crystal ghosts were greatly reduced in E2 enamel and in controls. CONCLUSIONS: The results lead to the conclusions that: (1) E1 enamel is hypomineralized, and its degree of calcification is restored by return to a normal calcium diet; (2) intra- and interprismatic calcification occurs in a different way; (3) crystallite thickness is initially greater in dentinal than in the superficial zone and is reversed as crystallite growth is completed; and (4) loss of enamel proteins is necessary for completion of crystallite growth and not for crystallite formation.

Animal Nutritional Physiological Phenomena↗
PubMed2004

Post-natal diet determines insulin resistance in fetally malnourished, low birthweight rats (F1) but diet does not modify the insulin resistance of their offspring (F2).

We examined the effects of prenatal and postnatal nutrition on birthweight and insulin sensitivity, indicated by the glucose/insulin (G/I) ratio, in adult rats (F1 generation) and in their adult offspring (F2 generation). Rat pups (F1) whose dams consumed low-protein diets during gestation (malnourished) consumed either nutritionally adequate (control) or high-fat diets ad libitum post-weaning. The offspring of these rats (F2) were maintained on the same diets as their respective dams. Separate pups (F1) whose dams consumed high-fat diets during gestation (over-nourished) were maintained on high-fat diets post-weaning, as were their offspring (F2). Birthweights were significantly reduced in all fetally malnourished F1 animals. At approximately 70 d of age, fasting insulin sensitivity in over-nourished F1 rats was significantly reduced compared to controls regardless of whether they were malnourished or over-nourished in utero; however, fetally malnourished F1 rats consuming control diets post-natally had significantly greater fasting insulin sensitivity than control animals. At 30 and 120 min post-glucose load, insulin sensitivity was reduced 12-65% in both groups of over-nourished F1 rats as compared to the fetally malnourished F1 rats consuming the control diet. Birthweights were significantly lower in F2 animals whose dams (F1) were fetally malnourished and weaned to high fat diets. Insulin sensitivity was significantly reduced in all F2 animals versus control animals, regardless of dietary treatment. Thus, post-natal diets alter insulin sensitivity in fetally malnourished, adult rats; and maternal malnutrition during gestation results in insulin resistance in offspring, irrespective of offsprings' birthweight or diet.

Animal Nutritional Physiological Phenomena↗
PubMed2004

Weight loss leads to reductions in inflammatory biomarkers after a very-low-carbohydrate diet and a low-fat diet in overweight men.

In recent years, it has become apparent that low-grade vascular inflammation plays a key role in all stages of the pathogenesis of atherosclerosis. Weight loss has been shown to improve blood inflammatory markers; however, it is unknown if weight-loss diets varying in macronutrient composition differentially affect inflammatory responses. The primary purpose of the present study was to compare a very-low-carbohydrate diet and a low-fat weight-loss diet on inflammatory biomarkers in overweight men. In a randomized cross-over design, 15 overweight men (body fat, >25%; body mass index, 34 kg/m2) consumed two experimental weight-loss diets for two consecutive 6-week periods: a very-low-carbohydrate diet (<10% energy via carbohydrate) and a low-fat diet (<30% energy via fat). Both the low-fat and the very-low-carbohydrate diets resulted in significant decreases in absolute concentrations of hsTNF-alpha (high-sensitivity tumour necrosis factor-alpha), hsIL-6 (high-sensitivity interleukin-6), hsCRP (high-sensitivity C-reactive protein) and sICAM-1 (soluble intercellular cell-adhesion molecule-1). There was no significant change in absolute sP-selectin (soluble P-selectin) concentrations after either diet. Normalized inflammatory values represented as the delta change per 1 kg reduction in body mass showed a significant difference between the two diets only for sP-selectin (P<0.05). In summary, energy-restricted low-fat and very-low-carbohydrate diets both significantly decreased several biomarkers of inflammation. These data suggest that, in the short-term, weight loss is primarily the driving force underlying the reductions in most of the inflammatory biomarkers.

Adult↗
PubMed2004

Energy-dense diets are associated with lower diet costs: a community study of French adults.

OBJECTIVE: High consumption of energy-dense foods has been linked to high energy intakes and excess weight gain. This study tested the hypothesis that high energy density of the total diet is associated with lower diet costs. DESIGN: Dietary intakes of 837 French adults, aged 18-76 years, were assessed using a dietary history method. Dietary energy density (MJ kg(-1)) was calculated by dividing total energy by the edible weight of foods consumed. Daily diet cost ( in day(-1)) was estimated using mean national food prices for 57 food items. The relationship between dietary energy density and diet cost at each level of energy intake was examined in a regression model, adjusted for gender and age. RESULTS: The more energy-dense refined grains, sweets and fats provided energy at a lower cost than did lean meats, vegetables and fruit. Within each quintile of energy intake, diets of lower energy density (MJ kg(-1)) were associated with higher diet costs ( in day(-1)). CONCLUSION: In this observational study, energy-dense diets cost less whereas energy-dilute diets cost more, adjusting for energy intakes. The finding that energy-dilute diets are associated with higher diet costs has implications for dietary guidelines and current strategies for dietary change.

Adolescent↗
PubMed1977

Effect of diet composition on metabolic adaptations to hypocaloric nutrition: comparison of high carbohydrate and high fat isocaloric diets.

The metabolic consequences of two hypocaloric diets were assessed in 10 obese men. The study, performed on a metabolic ward, compared the response of these men to two cholesterol-free liquid formula diets of differing composition (10 kcal/kg per day, 70% carbohydrate, 20% protein, 10% fat versus 70% fat, 20% protein, 10% carbohydrate) but identical in calories. These were administered for 14 days in a random order and each diet was preceded by a 7-day control weight maintenance diet (30 kcal/kg per day, 40% carbohydrate, 20% protein, 40% fat). The low calorie diets were well tolerated by the men and effected similar losses of nonaqueous body weight. Fasting glucose and insulin decreased significantly in these men after they ingested either weight loss diet for 14 days, but the change in each parameter was greater for high fat as compared to high carbohydrate (15% versus 7% and 67% versus 35%, respectively, P less than 0.01). In contrast, fasting glucagon concentration decreased in these subjects to a greater extent in response to the high carbohydrate diet (35% versus 16%, P less than 0.01). This adaptive response thus resulted in a 50% fall in insulin:glucagon molar ratio for high fat and no change for high carbohydrate weight loss. Despite these hormonal alterations no change in glucose tolerance was observed. Fasting serum triglyceride and cholesterol levels declined in these subjects to a greater extent following the high fat compared to the high carbohydrate regimen (45% versus 28%, P less than 0.01 and 8% versus 3%, not significant, respectively). These changes reflected decrements in very low density lipoproteins alone. Despite similar increments in free fatty acid levels, (350% versus 270%, not significant) serum ketone body (beta-hydroxybutyrate and acetoacetate) concentrations increased 7-fold on the high fat diet compared to the high carbohydrate diet, P less than 0.001. The hyperketonemia of these men in response to the high fat, low calorie diet suggested the occurrence of a shift in hepatic free fatty acid metabolism toward ketogenesis rather than triglyceride synthesis. The associated decrease in the insulin: glucagon molar ratio raised the question of a possible role for these hormones in the adaptation.

Adolescent↗
PubMed2006

Ketogenic low-carbohydrate diets have no metabolic advantage over nonketogenic low-carbohydrate diets.

BACKGROUND: Low-carbohydrate diets may promote greater weight loss than does the conventional low-fat, high-carbohydrate diet. OBJECTIVE: We compared weight loss and biomarker change in adults adhering to a ketogenic low-carbohydrate (KLC) diet or a nonketogenic low-carbohydrate (NLC) diet. DESIGN: Twenty adults [body mass index (in kg/m(2)): 34.4 +/- 1.0] were randomly assigned to the KLC (60% of energy as fat, beginning with approximately 5% of energy as carbohydrate) or NLC (30% of energy as fat; approximately 40% of energy as carbohydrate) diet. During the 6-wk trial, participants were sedentary, and 24-h intakes were strictly controlled. RESULTS: Mean (+/-SE) weight losses (6.3 +/- 0.6 and 7.2 +/- 0.8 kg in KLC and NLC dieters, respectively; P = 0.324) and fat losses (3.4 and 5.5 kg in KLC and NLC dieters, respectively; P = 0.111) did not differ significantly by group after 6 wk. Blood beta-hydroxybutyrate in the KLC dieters was 3.6 times that in the NLC dieters at week 2 (P = 0.018), and LDL cholesterol was directly correlated with blood beta-hydroxybutyrate (r = 0.297, P = 0.025). Overall, insulin sensitivity and resting energy expenditure increased and serum gamma-glutamyltransferase concentrations decreased in both diet groups during the 6-wk trial (P < 0.05). However, inflammatory risk (arachidonic acid:eicosapentaenoic acid ratios in plasma phospholipids) and perceptions of vigor were more adversely affected by the KLC than by the NLC diet. CONCLUSIONS: KLC and NLC diets were equally effective in reducing body weight and insulin resistance, but the KLC diet was associated with several adverse metabolic and emotional effects. The use of ketogenic diets for weight loss is not warranted.

3-Hydroxybutyric Acid↗
PubMed1981

Effect of some dietary additions to either an arginine-devoid diet or a diet supplemented with orotic acid refed after starvation on liver lipid content during essential fatty acid deficiency in rats.

Refeeding either an arginine-devoid diet or a 14% casein diet supplemented with 1% orotic acid for 7 days to starved rats caused an increase in liver lipid content which was prevented by the addition of adenine, allopurinol and safflower oil, but not guanine, cytosine, thymine and uracil. When rats were refed the arginine-devoid diet unsupplemented or supplemented with guanine, cytosine, thymine and uracil, their serum triglyceride and cholesterol decreased or tended to decrease as compared with those of rats refed the arginine-devoid diet supplemented with either adenine or allopurinol or rats refed the arginine-supplemented diet. Furthermore, triglyceride and cholesterol in serum of rats refed the arginine-devoid diet supplemented with either adenine or allopurinol increased as compared with those of rats refed the arginine-supplemented diet. The addition of either adenine or allopurinol to the arginine-devoid diet resulted in lowered lipid content in the liver as compared with the arginine-supplemented diet. Thus, when the arginine-devoid diet unsupplemented or supplemented with arginine, adenine and allopurinol was refed, liver lipid content was inversely related to the serum triglyceride level.

Adenine↗
PubMed1982

Effect of unpalatable diets, food restriction and saccharin-adulterated diet on tryptic, chymotryptic, and amylolytic activity in pancreas, intestine and feces of rats.

Growing rats were fed either 10 to 17% protein (casein) diets whose taste was changed daily by addition of aversive stimuli. Under these circumstances food intake and body weight gain were reduced compared with controls fed unadulterated diets. More amylolytic activity per gram pancreas was found in rats fed a 10% protein, aversive diet and in their pair-fed controls fed restricted amounts of an unadulterated diet compared with ad libitum controls. More amylolytic activity per gram chyme of small intestine was also found in rats fed less than ad libitum amounts of a 10% protein diet. The chymotrypsin activity in the pancreas of rats fed a 17% protein, aversive diet was greater than in that of control animals or that of the pair-fed animals. The 2- to 10-fold higher proteolytic activity found in the small intestine and especially in the large intestine and feces of rats fed the aversive diet was specifically related to the adulteration of the diet with sodium saccharin. Feeding a diet containing sodium saccharin led to lower cecal pH. Under conditions of the present experiments, changes in digestive enzyme activity are not directly related to the aversive taste of the diet.

Amylases↗
PubMed1992

Shifting from a conventional diet to an uncooked vegan diet reversibly alters fecal hydrolytic activities in humans.

We studied the effect on fecal hydrolytic activities of adopting an uncooked extreme vegan diet and readopting a conventional diet. Eighteen subjects were randomly divided into test and control groups. In the test group subjects adopted the uncooked extreme vegan diet for 1 mo and then resumed a conventional diet for a second month. Controls consumed a conventional diet throughout the study. Phenol and p-cresol concentrations in serum and daily output in urine and fecal enzyme activities were measured. The activity of fecal urease significantly decreased (by 66%) as did cholylglycine hydrolase (55%), beta-glucuronidase (33%) and beta-glucosidase (40%) within 1 wk of beginning the vegan diet. The new level remained throughout the period of consuming this diet. Phenol and p-cresol concentrations in serum and daily outputs in urine significantly declined. The fecal enzyme activities returned to normal values within 2 wk of resuming the conventional diet. Concentrations of phenol and p-cresol in serum and daily output in urine had returned to normal after 1 mo of consuming the conventional diet. No changes were observed in the control group during the study. Results suggest that this uncooked extreme vegan diet causes a decrease in bacterial enzymes and certain toxic products that have been implicated in colon cancer risk.

Adult↗
PubMed1993

AIN-93 purified diets for laboratory rodents: final report of the American Institute of Nutrition ad hoc writing committee on the reformulation of the AIN-76A rodent diet.

For sixteen years, the American Institute of Nutrition Rodent Diets, AIN-76 and AIN-76A, have been used extensively around the world. Because of numerous nutritional and technical problems encountered with the diet during this period, it was revised. Two new formulations were derived: AIN-93G for growth, pregnancy and lactation, and AIN-93M for adult maintenance. Some major differences in the new formulation of AIN-93G compared with AIN-76A are as follows: 7 g soybean oil/100 g diet was substituted for 5 g corn oil/100 g diet to increase the amount of linolenic acid; cornstarch was substituted for sucrose; the amount of phosphorus was reduced to help eliminate the problem of kidney calcification in female rats; L-cystine was substituted for DL-methionine as the amino acid supplement for casein, known to be deficient in the sulfur amino acids; manganese concentration was lowered to one-fifth the amount in the old diet; the amounts of vitamin E, vitamin K and vitamin B-12 were increased; and molybdenum, silicon, fluoride, nickel, boron, lithium and vanadium were added to the mineral mix. For the AIN-93M maintenance diet, the amount of fat was lowered to 40 g/kg diet from 70 g/kg diet, and the amount of casein to 140 g/kg from 200 g/kg in the AIN-93G diet. Because of a better balance of essential nutrients, the AIN-93 diets may prove to be a better choice than AIN-76A for long-term as well as short-term studies with laboratory rodents.

Animals↗