• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2627-2632
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• 2010

Hormone sensitive lipase (HSL) plays a major role in energy homeostasis and lipid metabolism. Several crystal structures of HSL-homolog proteins have been identified, which has led to a better understanding of its molecular function. HSL-homolog proteins exit as both monomer and dimer, but the biochemical and structural basis for such oligomeric states has not been successfully elucidated. Therefore, we determined the crystal structure of HSL-homolog protein EstE7 from a metagenome library at $2.2\;{\AA}$ resolution and characterized the oligomeric states of EstE7 both structurally and biochemically. EstE7 protein prefers the dimeric state in solution, which is supported by its higher enzymatic activity in the dimeric state. In the crystal form, EstE7 protein shows two-types of dimeric interface. Specifically, dimerization via the external ${beta}8$-strand occurred through tight association between two pseudosymmetric folds via salt bridges, hydrogen bonds and van der Waals interactions. This dimer formation was similar to that of other HSL-homolog protein structures such as AFEST, BEFA, and EstE1. We anticipate that our results will provide insight into the oligomeric state of HSL-homolog proteins.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.6
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• pp.827-835
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• 2009

Insulin has crucial roles in energy metabolism in all mammals but has been less studied in ruminants. An experiment was conducted to investigate the effects of hypoinsulinemia induction on appetite, performance, carcass composition and blood metabolite levels in sheep. Treatments were intravenous injection of four doses of streptozotocin; 0, 25, 50 and 75 mg/kg BW named C, L, M and H, respectively. Twenty male lambs were divided into four treatment groups. Animals in group H could not continue the experiment because of abnormalities. The duration of the experiment was eight consecutive weeks, and injection was performed at the end of week 3. Feed and water intakes were measured weekly and weight changes of animals were recorded and used for calculation of other growth parameters. Blood samples were collected weekly via venipuncture at fasting and 2.5 h post-prandial and analyzed for hormones and blood metabolites. Results showed a marked hypoinsulinemia in group M with significant decrease in fasted and postprandial insulin concentrations and also fasted leptin concentrations vs. the control group C (p<0.05). Group M showed significant increases in blood glucose, triglycerides, cholesterol, total protein, blood urea nitrogen and ketone body levels vs. group C (p<0.05). After injection, animals in group M showed diabetic hyperphagia and enhanced water intake as compared to group C (p<0.05) but, despite increased feed intake, they did not gain more weight than controls (p<0.05), and consequently, their feed conversion ratio was greater. Protein and fat contents of meat and liver were not significantly different among groups (p>0.05). In conclusion, the results suggested a regulatory role of insulin in energy metabolism of ruminants by exerting two opposing effects; central catabolic and peripheral anabolic.

• Natural Product Sciences
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• v.19 no.1
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• pp.1-7
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• 2013

AMP-activated protein kinase (AMPK) is a major cellular energy sensor and master regulator of metabolic homeostasis. On activation, this cellular fuel sensing enzyme induces a series of metabolic changes to balance energy consumption via multiple downstream signaling pathways controlling nutrient uptake and energy metabolism. This pivotal role of AMPK has led to the development of numerous AMPK activators which might be used as novel drug candidates in the treatment of AMPK related disorders, diabetes, obesity, and other metabolic diseases. Consequently, a number of patents have been published on AMPK activators from natural products and other sources. This review covers the patented AMPK activators from natural products and their therapeutic potential in treatment or prevention of metabolic diseases including diabetes and obesity.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.9
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• pp.1397-1406
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• 2019

Objective: Feed energy required for pigs is first prioritized to meet maintenance costs. Additional energy intake in excess of the energy requirement for maintenance is retained as protein and fat in the body, leading to weight gain. The objective of this study was to estimate the metabolizable energy requirements for maintenance ($ME_m$) by regressing body weight (BW) gain against metabolizable energy intake (MEI) in growing pigs. Methods: Thirty-six growing pigs ($26.3{\pm}1.7kg$) were allotted to 1 of 6 treatments with 6 replicates per treatment in a randomized complete block design. Treatments were 6 feeding levels which were calculated as 50%, 60%, 70%, 80%, 90%, or 100% of the estimated ad libitum MEI ($2,400kJ/kg\;BW^{0.60}\;d$). All pigs were individually housed in metabolism crates for 30 d and weighed every 5 d. Moreover, each pig from each treatment was placed in the open-circuit respiration chambers to measure heat production (HP) and energy retained as protein ($RE_p$) and fat ($RE_f$) every 5 d. Serum biochemical parameters of pigs were analyzed at the end of the experiment. Results: The average daily gain (ADG) and HP as well as the $RE_p$ and $RE_f$ linearly increased with increasing feed intake (p<0.010). ${\beta}$-hydroxybutyrate concentration of serum tended to increase with increasing feed intake (p = 0.080). The regression equations of MEI on ADG were MEI, $kJ/kg\;BW^{0.60}\;d=1.88{\times}ADG$, g/d+782 ($R^2=0.86$) and $ME_m$ was estimated at $782kJ/kg\;BW^{0.60}\;d$. Protein retention of growing pigs would be positive while REf would be negative at this feeding level via regression equations of $RE_p$ and $RE_f$ on MEI. Conclusion: The $ME_m$ was estimated at $782kJ/kg\;BW^{0.60}\;d$ in current experiment. Furthermore, growing pigs will deposit protein and oxidize fat if provided feed at the estimated maintenance level.

• YAKHAK HOEJI
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• v.54 no.6
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• pp.529-534
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• 2010

Alzheimer's disease (AD) is characterized pathologically by the presence of intracellular neurofibrillary tangles and deposition of ${\beta}$-amyloid ($A{\beta}$) peptides, which are generated by processing of amyloid precursor protein (APP). It is urgent to develop effective therapies for the treatment of AD, since our society rapidly accelerate aging. $A{\beta}$ peptides have been believed to be neurotoxic and now are also considered to have effects on the mechanism of memory formation. Recently, we investigated that a quinoline compound from natural product reduced the secretion of $A{\beta}$ from the neuroblastoma N2a cells (NL/N cell line) overexpressing APPswe. In this study, 3-phenyl-1-isoquinolinamine, a synthetic isoquinoline compound was analyzed to determine its effects on the metabolism of APP. It inhibited the secretion of $A{\beta}$ peptides from the N2a NL/N cell line. Beta-site APP cleaving enzyme (BACE) fluorescence resonance energy transfer (FRET) assay revealed that it inhibited BACE activity in a dose dependent manner. Immunoblotting study showed that it inhibited APP stabilization and expression and it slightly increased the stablization and the expression of ${\gamma}$-secreatase component from the N2a NL/N cell line. We suggest that 3-phenyl-1-isoquinolinamine inhibits APP metabolism and $A{\beta}$ generation by the means of BACE inhibitory mechanism. This is the first report that 3-phenyl-1-isoquinolinamine inhibits the secretion of $A{\beta}$ peptides from neuroblastoma cells.

• Journal of Animal Science and Technology
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• v.47 no.3
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• pp.379-390
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• 2005

Effects of dietary brown seaweed product levels on performance and metabolism of protein and energy were investigated in broiler chicks that were activated the acute phase response. One day old chicks were fed diets containing either 0.0(basal), 1.0, 2.0 or 4.0 % brown seaweed products for 3 weeks. The acute phase response was activated by injecting i.p. the Salmonella typhimurium lipopolysacharide(LPS) at $2^{nd}$ week of age. The acute phase response lowered nitrogen balance(NB)/ $kg^{0.75}$ (metabolic body size) and highered dietary ME values in birds fed diets containing brown seaweed product. Increase in dietary brown seaweed products levels lowered daily gain, and NB, uric acid nitrogen(UAN) excretion and ME utilization per $kg^{0.75}$ in chicks with the acute phase response. But the dietary brown seaweed product level did not affect the performance of 3 Week old broiler chicks that experienced the acute phase response. And the brown seaweed products 1.0 and 2.0 % diets lessened the feed intake reduction caused by the acute phase response in broiler chicks. The brown seaweed 2.0% diet increased NB / g diet or $kg^{0.75}$ and decreased the excretion of UAN/g diet or $kg^{0.75}$. This result indicated that the brown seaweed was able to interact with the acute phase response and increased protein retention via decreased breakdown of protein in birds fed brown seaweed 2.0% diet.

• Korean Journal of Agricultural Science
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• v.44 no.4
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• pp.586-594
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• 2017

Mitochondrial activity affects skeletal muscle energy metabolism and phenotype. To address whether mitochondrial activity can modulate muscle phenotype in vitro, protein expression of myosin heavy chain (MyHC) in C2C12 muscle cell lines was investigated after treated with antimycin A, an inhibitor of oxidative phosphorylation in mitochondria. Fully differentiated C2C12 myotubes were administrated with different concentration of antimycin A including 0, 100, 200, 500, 700, and 1000 ng/mL. After 72 h treatment, myosin heavy chain isoform expression and related enzyme activity (lactate dehydrogenase; LDH and creatine kinase) were analyzed. Administration of antimycin A changed expression of MyHC in C2C12 myotubes showing a shift from slow to fast twitching muscle type. Protein expression of MyHC type 2b (fast twitching muscle type) was decreased (P < 0.05) by antimycin A treatment (500, 700, and 1000 ng/mL) when compared with control group. Administration of antimycin A (1000 ng/mL), however, decreased (P < 0.05) MyHC type I (slow twitching muscle type). Interestingly, LDH activity was increased (P < 0.05) by antimycin A treatment. Results from our current study proposed a possibility that skeletal muscle phenotype, including MyHC and LDH activity, can be shifted from slow to fast twitching type by inhibiting the mitochondrial activity in C2C12 myotubes.

• Journal of Haehwa Medicine
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• v.4 no.1
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• pp.357-371
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• 1995

We have completed a study to measure the contents of glucose, BUN, creatinine. LDH, and T-protein with respect to a fatigued condition in the bloods of rats which a constant swimming is loaded and to measure the maximun swimming time of mice The test has been carried out as a part of the basic study on the efficacy of B. E. P. (Biological Energy Projector) for emitting a light energy having a specific wavelength out of far-infrared rays. As a result. We have reached the following conclusions: 1. At testing of mice's maximun swimming time, all of B.E.P.(2. 4. 8. 24hrs) treated group have been increased in comparison with the control group, but only 24hrs-B.E.P. treated group significantly increased during 4 weeks. 2. The contents of glucose, BUN. creatinine, LDH, and T-protein measured immediately after the swimming of mice have been distinctly changed but not been significantly changed at their increase and decrease in comparison with the control group. 3. At 3rd day out of the swimming loading, the contents of glucose in the blood serum of the white rat have been distinctly increased in comparison with the control group. And 24hrs-B.E.P treated group surpassed 8hrs-B.E.P. treated group. 4. At 1st and 3rd day, the contents of creatinine in the blood serum of the white rat have been distinctly increased at B.E.P. (8, 24hrs) treated groups in comparison with the control group and have been recovered to the condition of the normal group. 5. After three days, the contents of BUN in the blood serum of the white rat have been significantly decreased in B.E.P.(8, 24hrs) treated groups at 3rd day in comparison with the control group and have been recovered to the condition of the normal group. 6. The contents of LDH in the blood serum of the white rat have been decreased in B.E.P.(8, 24hrs) treated groups at 3rd day in comparison with the control group, in particular 24hrs-B.E.P. treated group has been decreased distinctly than the normal group. 7. The contents of T-protein in the blood serum of the white rat have been distinctly increased in B.E.P. (8, 24hrs) treated groups at 3rd day in comparison with the control and normal group. As the above results, it has been proved that the execise of mice and the fatigue metabolism of rats were influenced by the light energy emitted the B.E.P., and it has been also proved that the external stimulation could be used as a preferable stimulative factor for the biological metabolism. If the clinical training and study are positively achieved, the B.E.P. would be used as curative means and preventive measures for helping human body.

• The Plant Pathology Journal
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• v.34 no.4
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• pp.257-268
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• 2018

Rice blast disease, caused by Magnaporthe oryzae, results in an extensive loss of rice productivity. Previously, we identified a novel M. oryzae secreted protein, termed MSP1 which causes cell death and pathogen-associated molecular pattern (PAMP)-triggered immune (PTI) responses in rice. Here, we report the transcriptome profile of MSP1-induced response in rice, which led to the identification of 21,619 genes, among which 4,386 showed significant changes (P < 0.05 and fold change > 2 or < 1/2) in response to exogenous MSP1 treatment. Functional annotation of differentially regulated genes showed that the suppressed genes were deeply associated with photosynthesis, secondary metabolism, lipid synthesis, and protein synthesis, while the induced genes were involved in lipid degradation, protein degradation, and signaling. Moreover, expression of genes encoding receptor-like kinases, MAPKs, WRKYs, hormone signaling proteins and pathogenesis-related (PR) proteins were also induced by MSP1. Mapping these differentially expressed genes onto various pathways revealed critical information about the MSP1-triggered responses, providing new insights into the molecular mechanism and components of MSP1-triggered PTI responses in rice.

• Journal of Ginseng Research
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• v.38 no.2
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• pp.83-88
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• 2014

The adenosine monophosphate (AMP)-activated protein kinase (AMPK) is a key sensor of cellular energy. Once activated, it switches on catabolic pathways generating adenosine triphosphate (ATP), while switching off biosynthetic pathways consuming ATP. Pharmacological activation of AMPK by metformin holds a therapeutic potential to reverse metabolic abnormalities such as type 2 diabetes and nonalcoholic fatty liver disease. In addition, altered metabolism of tumor cells is widely recognized and AMPK is a potential target for cancer prevention and/or treatment. Panax ginseng is known to be useful for treatment and/or prevention of cancer and metabolic diseases including diabetes, hyperlipidemia, and obesity. In this review, we discuss the ginseng extracts and ginsenosides that activate AMPK, we clarify the various mechanisms by which they achieve this, and we discuss the evidence that shows that ginseng or ginsenosides might be useful in the treatment and/or prevention of metabolic diseases and cancer.