Biological Assay of Available Energy with Growing Chicks

Miniaturized bioassay technique, mini-test, was developed to estimate biologically available energy of a sample of only 5~50 g. Chicks were previously starved to keep body size minimum, then given either standard diets of three energy levels or test diets containing 5% of the sample for 6 days. Available energy of the sample was estimated on the standard curve showing linear relationship between dietary energy level and response of the chicks on the standard diets.

Reliability of the estimate by this mini-test was discussed based on linearity of the standard curve, 95% confidence interval of the estimate and available energy of 2 known carbohydrates estimated by this mini-test.     

Effect of Dietary Protein and Energy Levels on the Growth Rate,Feed Efficiency and Carcass Composition of Chicks

Feeding day-old White Leghorn male chicks 9 different diets for 4 weeks with the orthogonal composite design, we studied the relationship among dietary protein, energy levels and chick’s responses.

The ellipsoid relationship has been found fitted to describe the relationship between dietary composition and weight gain or feed efficiency of chicks, whereas declined planes are fitted to show the relationship between dietary composition and carcass protein or fat levels of chicks. Dietary protein level has great influence on nitrogen retention, but dietary energy level has little effect.

The linear relationship between total digestible nutrients and metabolizable energy in diets is presented.     

Availability of Energy in Alcohols,Aldehydes and Ketones by Growing Chicks

Biological availability of 23 alcohols, 16 aldehydes and 2 ketones was compared by the mini-test with chicks. Chicks can utilize methanol and ethanol, but not the alcohols of carbon chain from 3 to 9. Lauryl and myristyl alcohols were well utilized but those of higher carbon chain than 14 were not, mainly due to low digestibility. Glycerol and D-sorbitol were well utilized but not 4 other poly alcohols tested. Aldehydes and ketones with free carbonyl group showed low availability or even toxicity, but their derivatives with masked group showed no detrimental effect. Acetaldehyde, acetal and aldehydes of carbon chain longer than 9 were partially utilized.     

Availability of Energy in Ester and Ether Derivatives of Glycols by Growing Chicks

Biological availability of 33 esters, 17 ethers and 2 acetals of ethanediol, 1,2-propanediol, 1,3-butanediol and 1,4-butanediol was compared by mini-test with chicks. Chicks can utilize esters of ethanediol, 1,2-propanediol and 1,3-butanediol with acetic acid and fatty acids of carbon chain length from 5 to 12 with more improved palatability than that of free acids, while availability of esters of these glycols with propionic and butyric acids was low. Esters of 1,4-butanediol and ether derivatives of these glycols was not available, except ethyl ether of di-ethanediol which was partially available. Acetacetal of ethanediol was partially available but n-butyracetal was not.     

Availability of Energy in Esters of Aliphatic Acids and Alcohols by Growing Chicks

Biological availability of 106 esters of alcohols and aliphatic mono-, di- and tri-carboxylic acids and diethylene glycol succinate was compared by the mini-test with chicks. Chicks can utilize methyl esters of saturated fatty acids of carbon chain from 10 to 14, ethyl esters of those from 9 to 12, propyl caprate, n-butyl esters of those from 8 to 12, n-amyl esters of those from 6 to 12, n-hexyl n-butyrate and i-vaterate, and n-octyl and n-decyl acetates. Only 3 dicarboxylates, i.e. di-octyl and di-lauryl succinates and di-methyl cis-cyclopropane-l,2-dicarboxylate, were available among the dicarboxylates tested. Availability of ethyl esters of succinic, fumaric and citric, acid was unexpectedly low.     

Evaluation of Nutritive Value of Glycol Esters as Energy Source for Growing Chicks and Rats

Nutritive value of 4 glycol esters, i.e. ethanediol diacetate, 1,2-propanediol diacetate, 1,3-butanediol diacetate and 1,3-butanediol dioctylate, was estimated biologically by feeding the esters to growing chicks and rats. Energy in the esters taken by both chicks and rats was well utilized, though feed intake of the diets containing the esters at high level tended to decrease. Bitter taste of the esters was suspected to be related to low appetite. The acetates were somewhat volatile and released free acetic acid in the diet during storage. These properties of the acetates makes their use for dietary energy source difficult in practical condition.     

Effect of Insulin and Energy Restriction on the Thermic Effect of Protein in Type 2 Diabetes Mellitus

Objective: The objective of this study was to test whether the thermic effect of oral protein is blunted in poorly controlled type 2 diabetes and is corrected by normalization of glycemia with insulin and 28 days of a very‐low‐energy diet. Research Methods and Procedures: Resting energy expenditure (REE) and the thermic effect of 90 g of oral protein were measured, using indirect calorimetry, in nine (five women and four men) obese diabetic people [weight, 108 ± 10 kg; waist circumference, 123 ± 8 cm; body mass index, 40 ± 3 kg/m²] who were hyperglycemic on day 8 or euglycemic with insulin on day 16 of a weight‐maintaining diet and euglycemic on day 28 of a very low energy diet (VLED). Results were compared with those of seven (six women and one man) weight‐ and body mass index‐matched obese nondiabetic subjects with a waist circumference of 111 ± 6 cm. Substrates and hormonal responses were determined concurrently. Results: Fasting glucose was normalized in the diabetic subjects with insulin from day 9 of VLED onward. Weight decreased in both groups by 9.9 ± 0.9 kg with VLED. REE was 8 ± 2% lower with insulin treatment and decreased by another 14 ± 3% with VLED in the diabetic and by 15 ± 1% in the nondiabetic subjects by week 4. After the protein meal, the thermic response was significantly (p < 0.05) less with hyperglycemia than with insulin‐induced euglycemia, as percentage above REE (15.3 ± 1.4 compared with 21.2 ± 1.5%), as percentage of the energy content of the meal (19.5 ± 1.5 compared with 25.2 ± 1.7%), as kilocalories per 405 minutes (86 ± 5 compared with 110 ± 7), and less than in nondiabetic obese controls (21.0 ± 2.2% above REE, 24.4 ± 1.7% of energy of meal). After the VLED, the thermic effect of protein was significantly higher in both groups only as percentage above REE. The initial glucagon response was greater with hyperglycemia compared with euglycemia and post‐VLED but not compared with the nondiabetic subjects. Hyperglycemia was associated with 21 ± 4% greater urinary urea nitrogen excretion and urinary glucose losses of 134 ± 50 mmol/d. Discussion: This study shows a blunted thermic effect of protein in obese hyperglycemic type 2 diabetic subjects compared with matched nondiabetic subjects that can be corrected with insulin‐ or energy restriction‐induced euglycemia.     

TFAP2B Influences the Effect of Dietary Fat on Weight Loss under Energy Restriction

Background

Numerous gene loci are related to single measures of body weight and shape. We investigated if 55 SNPs previously associated with BMI or waist measures, modify the effects of fat intake on weight loss and waist reduction under energy restriction.

Methods and Findings

Randomized controlled trial of 771 obese adults. (Registration: ISRCTN25867281.) One SNP was selected for replication in another weight loss intervention study of 934 obese adults. The original trial was a 10-week 600 kcal/d energy-deficient diet with energy percentage from fat (fat%) in range of 20–25 or 40–45. The replication study used an 8-weeks diet of 880 kcal/d and 20 fat%; change in fat% intake was used for estimation of interaction effects. The main outcomes were intervention weight loss and waist reduction. In the trial, mean change in fat% intake was −12/+4 in the low/high-fat groups. In the replication study, it was −23/−12 among those reducing fat% more/less than the median. TFAP2B-rs987237 genotype AA was associated with 1.0 kg (95% CI, 0.4; 1.6) greater weight loss on the low-fat, and GG genotype with 2.6 kg (1.1; 4.1) greater weight loss on the high-fat (interaction p-value; p = 0.00007). The replication study showed a similar (non-significant) interaction pattern. Waist reduction results generally were similar. Study-strengths include (i) the discovery study randomised trial design combined with the replication opportunity (ii) the strict dietary intake control in both studies (iii) the large sample sizes of both studies. Limitations are (i) the low minor allele frequency of the TFAP2B polymorphism, making it hard to investigate non-additive genetic effects (ii) the different interventions preventing identical replication-discovery study designs (iii) some missing data for non-completers and dietary intake. No adverse effects/outcomes or side-effects were observed.

Conclusions

Under energy restriction, TFAP2B may modify the effect of dietary fat intake on weight loss and waist reduction.     

Ability of Glycol Esters of Fatty Acid Inducing Encephalomalacia in Growing Chicks

A number of amino acid derivatives of DL-Zra/w-epoxysuccinic acid, with a general formula of R₁O-ES-AA-OR₂ (ES, DL-trans-epoxysuccinyl group; AA, amino acid residue) were newly synthesized and used for the study of structure-activity relationships of papain inhibition. Branched-alkyl amino acids, such as Leu, He and Val, as AA and hydrogen or an alkyl group substituted with a phenyl or cycloalkyl group as R¹ were desirable for activity, respectively. However, R₂ or the optical activities of ES and AA not so much influenced on the activity.     

Metabolism of Serine in Growing Rats and Chicks at Various Dietary Protein Levels

The metabolic fate of the carbon skeleton of l-serine-U-¹⁴C has been investigated, in vivo and in vitro, in growing rats and chicks fed the diets with various protein calories percents (PC%) at 410 kcal of metabolizable energy.

The incorporation of ¹⁴C into body protein at 12 hr after the injection of serine-¹⁴C was about 49% of the injected dose in rats fed the 10 or 15 PC % diet, though the value was reduced in rats fed lower and higher protein diets. The ¹⁴CO₂ production was smaller in rats fed the 10 and 15 PC% diet, and it showed an inverse pattern to that of the ¹⁴C incorporation into body protein. Urinary excretion of ¹⁴C was higher in rats fed 10 and higher PC% diets, whose growth rate and net body protein retention were maximum.

In contrast to the case of rats, the incorporation of ¹⁴C into body protein of chicks at 6 hr after the injection was rather reduced in the 15 PC% group. The proportion of ¹⁴C excreted as uric acid was remarkably increased above the 10 PC% group, and about 19% of the injected dose was recovered in the 50 PC% group.

The catabolic rate of serine in the liver slices of rats and chicks was increased by high protein diets.

These results support the concept that the nutritional significance of metabolism of the carbon skeleton of serine in growing rats and chicks is different from each other, especially at high protein diets.     

饲料钙磷含量和钙磷比对生长期大鼠体重增长与骨骼发育的影响

目的研究饲料中不同的钙磷含量和钙磷比对生长期实验大鼠体重及骨骼发育的影响。方法采用完全随机化设计方案,取1月龄（100±10）g清洁级Wistar雄性大鼠70只,随机分成7组,每组10只,饲喂7种不同钙磷含量的饲料。自由采食,饮用去离子水,试验期42 d。各组于实验开始和结束时称重。试验结束后,处死动物并分离一侧胫骨和股骨用于实验指标的检测。结果当保持饲料中钙或者磷中的一种含量不变的情况下,调整另一种的含量即改变钙磷比例时,1.2∶1的正常钙磷比例组生长期实验大鼠增重及骨骼发育要明显好于0.4∶1的低钙磷比例组和4∶1的高钙磷比例组（P〈0.05）,并且当保持饲料中钙磷比例不变时,即使在低钙低磷和高钙高磷进食水平下,正常钙磷比例组大鼠增重及骨骼发育都较好,但低钙磷比例组和高钙磷比例组大鼠增重及骨骼发育则由于饲料中钙磷含量的变化波动较大（P〈0.05）。结论饲料中钙和磷需按比例添加,如果两者绝对含量相差过大就会影响到动物的增重及骨骼发育,本实验证明饲料钙磷比为1.2∶1时生长期实验大鼠增重及骨骼发育较好。     

Effect of Additional Boron on Tibias of African Ostrich Chicks

The aim of the present study was to find out the effects of boron on ostrich chicks fed with 0?mg/l, 100?mg/l, 200?mg/l, and 400?mg/l of additional boron in water. We measured bone mineral density (BMD), perimeter, length, weight, ash content of ostrich tibias, thickness of cortical bone, and diameter of the marrow cavity. We also analyzed the apoptosis status of paraffin sections using a TUNEL kit and examined serum levels of leptin and estradiol (E(2)). The results were dramatic. Compared with the control group, group C had a very high BMD. The serum levels of leptin in groups C and D were significantly higher than control values, and the levels of E(2) fluctuated. The perimeter, length, weight, and ash content of ostrich tibias all increased significantly with increasing dosage of boron. The cross-section analysis revealed that the bone marrow cavity shifted closer to one side in group D, which was observed on a macro-scale. This shift may be related to the toxicity of excessive boron, as indicated by the apoptosis status. According to the present data, additional boron was helpful for ostrich chick bone development, and 200?mg/l supplement boron in the drinking water appeared to be the most beneficial.     

Effect of Feed Restriction on Performance and Postprandial Nutrient Metabolism in Pigs Co-Infected with Mycoplasma hyopneumoniae and Swine Influenza Virus

As nutritional status and inflammation are strongly connected, feeding and nutritional strategies could be effective to improve the ability of pigs to cope with disease. The aims of this study were to investigate the impact of a feed restriction on the ability of pigs to resist and be tolerant to a coinfection with Mycoplasma hyopneumoniae (Mhp) and the European H1N1 swine influenza virus, and the consequences for nutrient metabolism, with a focus on amino acids. Two groups of specific pathogen-free pigs were inoculated with Mhp and H1N1 21 days apart. One group was fed ad libitum, the other group was subjected to a two-week 40% feed restriction starting one week before H1N1 infection. The two respective mock control groups were included. Three days post-H1N1 infection, 200 g of feed was given to pigs previously fasted overnight and serial blood samples were taken over 4 hours to measure plasma nutrient concentrations. Throughout the study, clinical signs were observed and pathogens were detected in nasal swabs and lung tissues. Feed-restricted pigs presented shorter hyperthermia and a positive mean weight gain over the 3 days post-H1N1 infection whereas animals fed ad libitum lost weight. Both infection and feed restriction reduced postprandial glucose concentrations, indicating changes in glucose metabolism. Post-prandial plasma concentrations of the essential amino acids histidine, arginine and threonine were lower in co-infected pigs suggesting a greater use of those amino acids for metabolic purposes associated with the immune response. Altogether, these results indicate that modifying feeding practices could help to prepare animals to overcome an influenza infection. Connections with metabolism changes are discussed.     

上海崇明东滩须浮鸥繁殖期雏鸟生长初步研究及首次雏鸟环志和彩色旗标

2005年夏季,对在崇明东滩繁殖孵化的须浮鸥Chlidonias hybrida雏鸟生长进行了研究,发现雏鸟孵化后至具飞行能力之前体重日增重3.52 g,时间为21天。此外,对29只雏鸟进行了国内首次的环志和彩色旗标系放工作。     

The Effect of Chlortetracycline Meditation on the Coliform Microflora of Newly Hatched Chicks

Newly hatched chicks were medicated with chlortetracycline at levels of 0, 400, 800 and 1200 mg. per imperial gallon of drinking water, for the first 5 days in the brooders. Coliform microflora of the ceca were counted when the chicks were first removed from the incubator and at 2 and 5 days of age. The numbers of coliforms decreased with increasing levels of the antibiotic and with increasing age. Sixtyfour per cent of the coliforms were E. coli and of these a large proportion were resistant to chlortetracycline and oxytetracycline in vitro. There was a trend towards increasing incidence of isolation of other resistant gram negative rods with increasing levels of chlortetracycline medication.     

Energy Restriction as an Antitumor Target of Thiazolidinediones

Cancer cells gain growth advantages in the microenvironment by shifting cellular metabolism to aerobic glycolysis, the so-called Warburg effect. There is a growing interest in targeting aerobic glycolysis for cancer therapy by exploiting the differential susceptibility of malignant versus normal cells to glycolytic inhibition, of which the proof-of-concept is provided by the in vivo efficacy of dietary caloric restriction and natural product-based energy restriction-mimetic agents (ERMAs) such as resveratrol and 2-deoxyglucose in suppressing carcinogenesis in animal models. Here, we identified thiazolidinediones as a novel class of ERMAs in that they elicited hallmark cellular responses characteristic of energy restriction, including transient induction of Sirt1 (silent information regulator 1) expression, activation of the intracellular fuel sensor AMP-activated protein kinase, and endoplasmic reticulum stress, the interplay among which culminated in autophagic and apoptotic death. The translational implications of this finding are multifold. First, the novel function of troglitazone and ciglitazone in targeting energy restriction provides a mechanistic basis to account for their peroxisome proliferator-activated receptor γ-independent effects on a broad spectrum of signaling targets. Second, we demonstrated that Sirt1-mediated up-regulation of β-transducin repeat-containing protein-facilitated proteolysis of cell cycle- and apoptosis-regulatory proteins is an energy restriction-elicited signaling event and is critical for the antitumor effects of ERMAs. Third, it provides a molecular rationale for using thiazolidinediones as scaffolds to develop potent ERMAs, of which the proof-of-principle is demonstrated by OSU-CG12. OSU-CG12, a peroxisome proliferator-activated receptor γ-inactive ciglitazone derivative, exhibits 1- and 3-order of magnitude higher potency in eliciting starvation-like cellular responses relative to resveratrol and 2-deoxyglucose, respectively.     

Effects of Niacin Restriction on Sirtuin and PARP Responses to Photodamage in Human Skin

Sirtuins (SIRTs) and poly(ADP-ribose) polymerases (PARPs), NAD(+)-dependent enzymes, link cellular energy status with responses to environmental stresses. Skin is frequently exposed to the DNA damaging effects of UV irradiation, a known etiology in skin cancer. Thus, understanding the defense mechanisms in response to UV, including the role of SIRTs and PARPs, may be important in developing skin cancer prevention strategies. Here, we report expression of the seven SIRT family members in human skin. SIRTs gene expressions are progressively upregulated in A431 epidermoid carcinoma cells (SIRTs1 and 3), actinic keratoses (SIRTs 2, 3, 5, 6, and 7) and squamous cell carcinoma (SIRTs 1-7). Photodamage induces dynamic changes in SIRT expression with upregulation of both SIRT1 and SIRT4 mRNAs. Specific losses of SIRT proteins occur early after photodamage followed by accumulation later, especially for SIRT4. Niacin restriction, which decreases NAD(+), the sirtuin substrate, results in an increase in acetylated proteins, upregulation of SIRTs 2 and 4, increased inherent DNA damage, alterations in SIRT responses to photodamage, abrogation of PARP activation following photodamage, and increased sensitivity to photodamage that is completely reversed by repleting niacin. These data support the hypothesis that SIRTs and PARPs play important roles in resistance to photodamage and identify specific SIRTs that respond to photodamage and may be targets for skin cancer prevention.