• Asian-Australasian Journal of Animal Sciences
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• 제14권5호
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• pp.720-732
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• 2001

Skeletal muscle is of major economic importance since it is finally converted to meat for consumers. The increase in meat production with low costs of production may be achieved by optimizing muscle growth, whereas a high meat quality requires, among other factors, the optimization of intramuscular glycogen and fat stores. Thus, research in energy metabolism aims at controling muscle metabolism, but also liver and adipose tissue metabolism in order to optimize energy partitioning in favour of muscles. Liver is characterized by high anabolic and catabolic rates. Metabolic enzymes are regulated by nutrients through short-term regulation of their activities and long-term regulation of expression of their genes. Consequences of liver metabolic regulation on energy supply to muscles may affect protein deposition (and hence growth) as well as intramuscular energy stores. Adipose tissues are important body reserves of triglycerides, which result from the balance between lipogenesis and lipolysis. Both processes depend on the feeding level and on the nature of nutrients, which indirectly affect energy delivery to muscles. In muscles, the regulation of rate-limiting nutrient transporters, of metabolic enzyme activities and of ATP production, as well as the interactions between nutrients affect free energy availability for muscle growth and modify muscle metabolic characteristics which determine meat quality. The growth of tissues and organs, the number and the characteristics of muscle fibers depend, for a great part, on early events during the fetal life. They include variations in quantitative and qualitative nutrient supply to the fetus, and hence in maternal nutrition. During the postnatal life, muscle growth and characteristics are affected by the age and the genetic type of the animals, the feeding level and the diet composition. The latter determines the nature of available nutrients and the rate of nutrient delivery to tissues, thereby regulating metabolism. Physical activity at pasture also favours the orientation of muscle metabolism, towards the oxidative type. Consequently, breeding systems may be of a great importance during the postnatal life. Research is now directed towards the determination of individual tissue and organ energy requirements, a better knowledge of nutrient partitioning between and within organs and tissues. The discovery of new molecules (e. g. leptin), of new molecular mechanisms and of more powerful techniques (DNA chips) will help to achieve these objectives. The integration of the different levels of knowledge will finally allow scientists to formulate new types of diets adapted to sustain a production of high quality meat with lower costs of production.

• 한국가정과교육학회지
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• 제12권3호
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• pp.53-63
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• 2000

The purpose of this study was quantitative and qualitative contents analysis of food and nutrition section in middle school textbooks of home economics, physical education and science. As a quantitative approach numbers of sentence lines tables, figures, photos, activities, and exercises were counted. As a qualitative approach, types of explanations were categorized by 7 criteria, and commons and differences of the contents of those subjects were compared. The conclusions of this study were summarized as follows: 1) Contents of food and nutrition section were divided into nutrients. water. energy, food groups, and nutritional problems. When average sentence lines of each were compared, those of nutrients were the longest in all 3 subjects. 2) When compared the numbers of tables, figures, and photos in 3 subjects of textbooks, there were more figures in home economics and science, and more tables in physical education. 3) There were more activities and exercises in home economics an science than in physical education. 4) The D(sentences with table) or E type(sentences with figure) was adapted for the explanation of nutrients functions, recommended dietary allowance, food sources, food groups, eating habits, and weight control in home economics: nutritions functions and energy metabolism in physical education : and digestion, body constituents, energy metabolism, and detection of nutrients in science. 5) Contents about classification and functions of nutrients. food sources deficiency water, energy contents of nutrients and obesity were shown in all 3 subjects. Food groups and eating habits were explained in detail in home economics whereas digestion of nutrients in the digestive tracts were explained in detail in science. Recommended dietary allowance for Koreans and basic food groups revised in 1995 were presented in home economics, whereas those revised in 1989 were presented in physical education. To avoid confusion, recommended dietary allowance for Koreans and food groups presented in physical education tex should be updated.

• Nutrition Research and Practice
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• 제17권4호
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• pp.597-615
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• 2023

Healthy aging can be defined as an extended lifespan and health span. Nutrition has been regarded as an important factor in healthy aging, because nutrients, bioactive food components, and diets have demonstrated beneficial effects on aging hallmarks such as oxidative stress, mitochondrial function, apoptosis and autophagy, genomic stability, and immune function. Nutrition also plays a role in epigenetic regulation of gene expression, and DNA methylation is the most extensively investigated epigenetic phenomenon in aging. Interestingly, age-associated DNA methylation can be modulated by one-carbon metabolism or inhibition of DNA methyltransferases. One-carbon metabolism ultimately controls the balance between the universal methyl donor S-adenosylmethionine and the methyltransferase inhibitor S-adenosylhomocysteine. Water-soluble B-vitamins such as folate, vitamin B6, and vitamin B12 serve as coenzymes for multiple steps in one-carbon metabolism, whereas methionine, choline, betaine, and serine act as methyl donors. Thus, these one-carbon nutrients can modify age-associated DNA methylation and subsequently alter the age-associated physiologic and pathologic processes. We cannot elude aging per se but we may at least change age-associated DNA methylation, which could mitigate age-associated diseases and disorders.

• Journal of Nutrition and Health
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• 제38권1호
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• pp.67-75
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• 2005

This study was performed to examine the change of lipid metabolism and immune function caused by antioxidant material in hypercholesterolemic elderly women (serum total cholesterol $\geq$200 mg/dI). The subjects were 51 elderly women aged over 60 yrs. They were divided into antioxidant nutrients complex group (n = 25) and spirulina group (n= 26). Antioxidant nutrients complex (1 capsule/day) and spirulina (7.5 mg/day) were used for intervention for 8weeks. All the subjects were fully informed the purpose of study and gave written consents to participate in this study. Dietary intakes, anthropometric indices and blood assessment for lipid, immune function and antioxidant status were measured before and after supplementation. Either antioxidant nutrients complex or spirulina supplementation for 8weeks resulted in improved antioxidant status evidence by increased TAS (total antioxidant status) and decreased TB-ARS (thiobarbituric acid reactive substance) . This intervention led to decreased serum levels of total cholesterol, LDL-cholesterol, oxLDL, apolipoprotein B, IL-6 and IL-6 production by peripheral blood lymphocyte. In conclusion, the lipid profiles, immune function and antioxidant capacity were improved after either antioxidant nutrient complex or spirulina supplementation for hypercholesterolemic women. Therefore, improving antioxidant status using supplemen-tation could provide means of controlling cardiovascular disease in Korean elderly people.

• 한국식품영양과학회지
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• 제21권2호
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• pp.219-230
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• 1992

영양소와 약물은 생물학적 운명 -즉, 흡수.대사.배설 과정이 유사하여 이 과정에서 상호 작용한다. 약물은 영양소의 흡수.대사.배설에 영향을 미치고 이로 인해 영양상태를 변화시킬 수 있다. 또한 영양상태 및 식이요인은 약물의 이용상태를 변경시킬 수 있다. 따라서 약물치료를 받는 개개인은 좋은 영양상태 유지를 위한 지식을 필요로 하고, 그 질병과 연계한 식이 변형의 중요성을 인식하여야 한다. 영양가 높고 균형 잡힌 식사가 개인의 건강을 유지하는데는 물론이고 영양 불량이나 약물의 약리작용 변경으로 인한 위험을 감소시킬 수 있다.

• Preventive Nutrition and Food Science
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• 제22권2호
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• pp.81-89
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• 2017

Healthy aging has become a major goal of public health. Many studies have provided evidence and theories to explain molecular mechanisms of the aging process. Recent studies suggest that epigenetic mechanisms are responsible for life span and the progression of aging. Epigenetics is a fascinating field of molecular biology, which studies heritable modifications of DNA and histones that regulate gene expression without altering the DNA sequence. DNA methylation is a major epigenetic mark that shows progressive changes during aging. Recent studies have investigated aging-related DNA methylation as a biomarker that predicts cellular age. Interestingly, growing evidence proposes that nutrients play a crucial role in the regulation of epigenetic modifiers. Because various nutrients and their metabolites function as substrates or cofactors for epigenetic modifiers, nutrition can modulate or reverse epigenetic marks in the genome as well as expression patterns. Here, we will review the results on aging-associated epigenetic modifications and the possible mechanisms by which nutrition, including nutrient availability and bioactive compounds, regulate epigenetic changes and affect aging physiology.

• 한국가금학회지
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• 제51권2호
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• pp.27-37
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• 2024

The poultry plays a crucial role in the animal industry, providing humans with efficient, high-quality animal protein. The rapid growth and short generational intervals of broilers offer significant benefits compared to other economic animals. This growth and increased muscle mass in modern commercial broilers result from advancements in breeding. However, the high productivity of contemporary broilers indicates they are approaching their physiological limits, with excessive fat accumulation becoming a significant industry issue. This not only reduces lean meat yield and feed efficiency but also negatively impacts consumers, especially due to problematic abdominal fat, which consumes more energy than lean meat production. Laying hens, reared for extended periods, maintain high productivity, producing a substantial number of eggs. This productivity in laying hens, akin to broilers, stems from genetic selection and breeding. For egg production, laying hens require physiological support for necessary nutrients. In this context, yolk fat accumulation is a critical physiological process. Lipoproteins, essential in avian lipid metabolism, are vital for yolk and body fat accumulation. Understanding these lipoproteins and their metabolism is key to developing healthier, more productive animals, offering economic benefits to farmers and improved nutritional quality to consumers. This review focuses on the physiological aspects of dietary fat transport, fatty acid biosynthesis in the liver, fat accumulation in the abdomen and muscles, and lipid deposition in egg yolks in chickens. It also highlights recent research trends in the regulation of fat metabolism in poultry.

• Asian-Australasian Journal of Animal Sciences
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• 제18권12호
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• pp.1721-1726
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• 2005

The characteristic smell of cow milk was suppressed when herbs were consumed by lactating dairy cows. But it is unclear whether or not peppermint ingestion affects the nutritional and milk production parameters in lactating dairy cows. The objective of this study was to examine the effect of peppermint feeding to lactating dairy cows on nutrient digestibility, energy metabolism, ruminal fermentation and milk production. Eight Holstein cows were given a diet supplemented with or without 5% of dried peppermint per diet on a dry matter basis. The digestion of nutrients from cows fed the diet with peppermint was significantly lower than that of the control group. Energy loss as methane and methane released from cows receiving the peppermint treatment was significantly lower than that in the control cows. Peppermint feeding to cows resulted in the promotion of thermogenesis. However, ruminal fermentation and milk production were not affected by peppermint feeding. In conclusion, peppermint ingestion by lactating dairy cows reduces the nutrient digestibility and methanogenesis, and changes energy metabolism.

• Asian-Australasian Journal of Animal Sciences
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• 제9권5호
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• pp.563-566
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• 1996

Five crossbred heifers(Holstein Friesian $\times$ Hariana) aged about one year and average body weight 157.0 kg were used to observe the effect of UMLD with restricted amount of wheat straw (500 g/100 kg body weight) on body weight gain and nutrient utilization. After seven months feeding the animals were switched to a revival diet consisted of wheat straw and concentrate mixture, for an additional six months. Fortnightly body weights were recorded and metabolism trials were conducted at the end of the two experimental periods. Results indicated that the average daily gain were 57.0 and 413.3 g in two feeding systems. This showed a sub-optimum growth during UMLD feeding which was compensated when good quality revival diet was available. Though, the nutrients intake were significantly (p < 0.01) lower in UMLD feeding period as compared to revival diet feeding, but digestibility of all the nutrients were alike statistically. It can be concluded that UMLD with restricted amount of wheat straw can be fed as scarcity feed for a short period, without causing irreparable loss to the animals, provided sufficient feed nutrients are available after the scarcity period.

• Animal Bioscience
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• 제36권2_spc호
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• pp.350-363
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• 2023

Beef quality is characterized by marbling (marbling degree and marbling fineness), physiochemical (shear force, meat color, fat color, texture, and maturity), and sensory (tenderness, flavor, juiciness, taste, odor, and appearance) traits. This paper summarizes and addresses beef-quality characteristics and the beef-grading systems in Korea, Japan, the USA, and Australia. This paper summarizes recent research progresses on the genetic and nutritional factors that affect beef quality. Intramuscular (i.m.) adipose tissue deposition or marbling is a major determinant of beef quality. This paper addresses the mechanisms of i.m. adipose tissue deposition focused on adipogenesis and lipogenesis. We also address selected signaling pathways associated with i.m. adipose tissue deposition. Nutrients contribute to the cellular response and phenotypes through gene expression and metabolism. This paper addresses control of gene expression through several nutrients (carbohydrates, fat/fatty acids, vitamins, etc.) for i.m. adipose tissue deposition. Several transcription factors responsible for gene expression via nutrients are addressed. We introduce the concept of genome-based precision feeding in Korean cattle.