• Asian-Australasian Journal of Animal Sciences
• /
• v.29 no.12
• /
• pp.1756-1760
• /
• 2016

Estimation of feed intake (FI) for individual animals within a pen is needed in situations where more than one animal share a feeder during feeding trials. A partitioning method (PM) was previously published as a model to estimate the individual FI (IFI). Briefly, the IFI of a pig within the pen was calculated by partitioning IFI into IFI for maintenance ($IFI_m$) and IFI for growth. In the PM, $IFI_m$ is determined based on the metabolic body weight (BW), which is calculated using the coefficient of 106 and exponent of 0.75. Two simulation studies were conducted to test the hypothesis that the use of different coefficients and exponents for metabolic BW to calculate $IFI_m$ improves the accuracy of the estimates of IFI for pigs, and that PM is applied to pigs fed in group-housing systems. The accuracy of prediction represented by difference between actual and estimated IFI was compared using PM, ratio (RM), or averaging method (AM). In simulation studies 1 and 2, the PM estimated IFI better than the AM and RM during most of the periods (p<0.05). The use of 0.60 as the exponent and the coefficient of 197 to calculate metabolic BW did not improve the accuracy of the IFI estimates in both simulation studies 1 and 2. The results imply that the use of $197kcal{\times}kg\;BW^{0.60}$ as metabolizable energy for maintenance in PM does not improve the accuracy of IFI estimations compared with the use of $106kcal{\times}kg\;BW^{0.75}$ and that the PM estimates the IFI of pigs with greater accuracy compared with the averaging or ratio methods in group-housing systems.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.23 no.6
• /
• pp.1241-1246
• /
• 2009

It has been suggested that Tae-Eum peoples are prone to obesity. Although extensive clinical observations have shown this tendency in Sasang Constitutional Medicine (SCM), no scientific hypothesis has been proposed to delineate its mechanism. According to SCM theory, Tae-Eum peoples have a hypoactive lung system and a hyperactive liver system. In this paper we propose a new hypothesis explaining the tendency of obesity in Tae-Eum people in the viewpoint of cell physiology. The hypoactive lung system might imply an attenuated 'respiration' at the cell/subcell level, namely mitochondrial oxygen consumption. Because a functional weakness in mitochondria energy metabolism indicates intrinsic hypo-activity in the consumption (or production) of metabolic energy, we deduced that the tendency can easily induce body weight gain via an increase in anabolism. This relation is also introduced in the graph of cellular metabolic power against body weight. To test this hypothesis, we analyzed the clinical data with 863 subjects. Statistical analysis of the data showed that Tae-Eum peoples had relatively a lower cellular metabolic power, and that the percentage of peoples with BMI>25 was significantly higher than that of the other constitutional types.

• Journal of Nutrition and Health
• /
• v.55 no.1
• /
• pp.70-84
• /
• 2022

Purpose: Skeletal muscles display significant heterogeneity in metabolic responses, owing to the composition of metabolically distinct fiber types. Recently, numerous studies have reported that in skeletal muscles, suppression of genes related to fatty acid channeling alters the triacylglycerol (TAG) synthesis and switches the energy substrates. However, such responses may differ, depending on the type of muscle fiber. Hence, we conducted in vitro and animal studies to compare the metabolic responses of different types of skeletal muscle fibers to the deficiency of fatty acyl-CoA synthetase (Acsl)6, one of the main fatty acid-activating enzymes. Methods: Differentiated skeletal myotubes were transfected with selected Acsl6 short interfering RNA (siRNA), and C57BL/6J mice were subjected to siRNA to induce Acsl6 deficiency. TAG accumulation and expression levels of insulin signaling proteins in response to acute glucose supplementation were measured in immortalized cell-based skeletal myotubes, oxidative muscles (OM), and glycolytic muscles (GM) derived from the animals. Results: Under conditions of high glucose supplementation, suppression of the Acsl6 gene resulted in decreased TAG and glycogen synthesis in the C2C12 skeletal myotubes. The expression of Glut4, a glucose transporter, was similarly downregulated. In the animal study, the level of TAG accumulation in OM was higher than levels determined in GM. However, a similar decrease in TAG accumulation was obtained in the two muscle types in response to Acsl6 suppression. Moreover, Acsl6 suppression enhanced the phosphorylation of insulin signaling proteins (Foxo-1, mTORc-1) only in GM, while no such changes were observed in OM. In addition, the induction ratio of phosphorylated proteins in response to glucose or Acsl6 suppression was significantly higher in GM than in OM. Conclusion: The results of this study demonstrate that Acsl6 differentially regulates the energy metabolism of skeletal muscles in response to glucose supplementation, thereby indicating that the fiber type or fiber composition of mixed muscles may skew the results of metabolic studies.

• The Korean Journal of Physiology and Pharmacology
• /
• v.26 no.5
• /
• pp.357-365
• /
• 2022

Simultaneous myofibril and mitochondrial development is crucial for the cardiac differentiation of pluripotent stem cells (PSCs). Specifically, mitochondrial energy metabolism (MEM) development in cardiomyocytes is essential for the beating function. Although previous studies have reported that MEM is correlated with cardiac differentiation, the process and timing of MEM regulation for cardiac differentiation remain poorly understood. Here, we performed transcriptome analysis of cells at specific stages of cardiac differentiation from mouse embryonic stem cells (mESCs) and human induced PSCs (hiPSCs). We selected MEM genes strongly upregulated at cardiac lineage commitment and in a time-dependent manner during cardiac maturation and identified the protein-protein interaction networks. Notably, MEM proteins were found to interact closely with cardiac maturation-related proteins rather than with cardiac lineage commitment-related proteins. Furthermore, MEM proteins were found to primarily interact with cardiac muscle contractile proteins rather than with cardiac transcription factors. We identified several candidate MEM regulatory genes involved in cardiac lineage commitment (Cck, Bdnf, Fabp4, Cebpα, and Cdkn2a in mESC-derived cells, and CCK and NOS3 in hiPSC-derived cells) and cardiac maturation (Ppargc1α, Pgam2, Cox6a2, and Fabp3 in mESC-derived cells, and PGAM2 and SLC25A4 in hiPSC-derived cells). Therefore, our findings show the importance of MEM in cardiac maturation.

• Toxicological Research
• /
• v.31 no.4
• /
• pp.323-330
• /
• 2015

Cancer is a disease characterized by uncontrolled growth. Metabolic demands to sustain rapid proliferation must be compelling since aerobic glycolysis is the first as well as the most commonly shared characteristic of cancer. During the last decade, the significance of metabolic reprogramming of cancer has been at the center of attention. Nonetheless, despite all the knowledge gained on cancer biology, the field is not able to reach agreement on the issue of mitochondria: Are damaged mitochondria the cause for aerobic glycolysis in cancer? Warburg proposed the damaged mitochondria theory over 80 years ago; the field has been testing the theory equally long. In this review, we will discuss alterations in metabolic fluxes of cancer cells, and provide an opinion on the damaged mitochondria theory.

• Korean Journal of Psychosomatic Medicine
• /
• v.3 no.2
• /
• pp.197-206
• /
• 1995

Obesity is a major nutritional problem in the developed countries. The prevalence of obesity may range from 10 to 50 per rent or mort of adult population and it may be increasing tendency. Many efforts have been made to understand the pathogenesis of obesity, but except a few metabolic obesities in the most of obese patients, the mechanisms are not understood. The treatment modalities of obesity, ranging from dietary and pubilc health intervention through the pharmacological and surgical therapy, have been developed and tested. In the obese patients mortalities and mobilities are significantly increased than non obese subjects due to hypertension, diabetics, and other problems. There are four possible mechanisms by which energy balance might be altered to enhance metabolic efficiency. futile metabolic pathway, alteration of protein rum over, alteration in sodium-potassium ATPase and alteration in uncoupled oxidation in brown adipose tissue are considered as possible mechanisms. Low calory and very low calory diets are recommended as a dietary program. Several pharmacological agent such as benzphetamine, fenfluramine, mazindol and fluoxetin are currently popular drugs for the treatment of obesity.

• Journal of the Korean Magnetic Resonance Society
• /
• v.26 no.4
• /
• pp.59-65
• /
• 2022

Benzo[a]pyrene (BaP), one of the polycyclic aromatic hydrocarbons (PAHs), is an endocrine disruptor and carcinogenic. This study was conducted to investigate the metabolic changes of zebrafish short-term exposure to BaP using nuclear magnetic resonance (NMR) spectroscopy. In our results, the multivariate analysis showed that the metabolic responses were differed according to the exposure concentration. Also, it was observed that exposure to high concentration of BaP (162 ㎍/L and 1620 ㎍/L) increased the levels of creatine, histidine, and inosine in zebrafish, which means high concentration of BaP exposure affected the energy metabolism and immune function in zebrafish.

• Applied Chemistry for Engineering
• /
• v.25 no.2
• /
• pp.134-141
• /
• 2014

As the concerns about environmental problems, climate change and limited fossil resources increase, bio-based production of chemicals and polymers from renewable resources gains much attention as one of the promising solutions to deal with these problems. To solve these problems, much effort has been devoted to the development of sustainable process using renewable resources. Recently, many chemicals and polymers have been synthesized by biorefinery process and these bio-based chemicals and plastics have been suggested as strong candidates to substitute petroleum-based products. In this review, we discuss current advances on the development of metabolically engineered microorganisms for the efficient production of bio-based chemicals and polymers.

• Journal of the Korean Magnetic Resonance Society
• /
• v.15 no.1
• /
• pp.54-68
• /
• 2011

$^1H$ nuclear magnetic resonance (NMR) spectroscopy of biological samples has been proven to be an effective and nondestructive approach to probe drug toxicity within an organism. In this study, ketoprofen toxicity was investigated using $^1H$-NMR spectroscopy coupled with multivariate statistical analysis. Histopathologic test of ketoprofen-induced acute gastrointestinal damage in rats demonstrated a significant dose-dependent effect. Furthermore, principal component analysis (PCA) derived from $^1H$-NMR spectra of urinary samples showed clear separation between the vehicle-treated control and ketoprofen-treated groups. Moreover, PCA derived from endogenous metabolite concentrations through targeted profiling revealed a dose-dependent metabolic shift between the vehicle-treated control, low-dose ketoprofen-treated (10 mg/kg body weight), and high-dose ketoprofen-treated (50 mg/kg) groups coinciding with their gastric damage scores after ketoprofen administration. The resultant metabolic profiles demonstrated that the ketoprofen-induced gastric damage exhibited energy metabolism perturbations that increased urinary levels of citrate, cis-aconitate, succinate, and phosphocreatine. In addition, ketoprofen administration induced an enhancement of xenobiotic activity in fatty oxidation, which caused increase levels of N-isovalerylglycine, adipate, phenylacetylglycine, dimethylamine, betaine, hippurate, 3-indoxylsulfate, N,N-dimethylglycine, trimethyl-N-oxide, and glycine. These findings demonstrate that $^1H$-NMR-based urinary metabolic profiling can be used for noninvasive and rapid way to diagnose adverse drug effects and is suitable for explaining the possible biological pathways perturbed by nonsteroidal anti-inflammatory drug toxicity.

• The Korean Journal of Food And Nutrition
• /
• v.26 no.3
• /
• pp.515-525
• /
• 2013

This study was performed to investigate the characteristics of nutrient intake according to metabolic syndrome in Korean elderly. Data on 1,200 elderly (men 545, women 655) over 65 years was obtained from the Korea National Health and Nutrition Examination Survey 2010. The subjects were divided into metabolic syndrome (MetS) and normal groups based on NCEP-ATP III guidelines and by applying the Asia-Pacific definition with waist circumference. The prevalence of MetS was 48.9% in all subjects, 35.6% in men and 58.9% in women, respectively. All nutrient intake was significantly lower in MetS than normal subjects, except iron, vitamin A, carotene, and retinol. In the carbohydrate: protein: fat (C:P:F) ratio, MetS showed a higher rate for carbohydrate, but a lower rate for protein and fat than normal. MetS was lower in calcium, vitamin B1, and vitamin C by the nutrient adequacy ratio than normal. Mean adequacy ratio of MetS (0.69) was lower than that of the normal group (0.72). These results demonstrated that undernutrition, not excess intake of specific nutrients - energy, fat, or cholesterol was associated with the risk for MetS in Korean elderly with MetS. Therefore, it is recommended to have a healthy dietary pattern with diverse nutrients for the prevention of MetS.