• 한국동물생명공학회지
• /
• 제38권1호
• /
• pp.10-16
• /
• 2023

Intermuscular fat is essential for enhancing the flavor and texture of cultured meat. Mesenchymal stem cells derived from intermuscular adipose tissues are a source of intermuscular fat. Therefore, as a step towards developing a platform to derive intermuscular fat from mesenchymal stem cells (MSCs) for insertion between myofibrils in cultured beef, an advanced protocol of intermuscular adipose tissue dissociation effective to the isolation of MSCs from intermuscular adipose tissues was developed in cattle. To accomplish this, physical steps were added to the enzymatic dissociation of intermuscular adipose tissues, and the MSCs were established from primary cells dissociated with physical step-free and step-added enzymatic dissociation protocols. The application of a physical step (intensive shaking up) at 5 minutes intervals during enzymatic dissociation resulted in the greatest number of primary cells derived from intermuscular adipose tissues, showed effective formation of colony forming units-fibroblasts (CFU-Fs) from the retrieved primary cells, and generated MSCs with no increase in doubling time. Thus, this protocol will contribute to the stable supply of good quality adipose-derived mesenchymal stem cells (ADMSCs) as a fat source for the production of marbled cultured beef.

• IMMUNE NETWORK
• /
• 제6권4호
• /
• pp.169-178
• /
• 2006

Background: Adipose tissues were initially introduced as energy storages, but recently they have become famous as an endocrine organ which produces and secretes various kinds of molecules to make physiologic and metabolic changes in human body. It has been studied that these molecules are secreted in abundance as the adipose tissue becomes bigger along with obesity. Furthermore, it has been found that they are mediating systemic inflammation and generation of metabolic diseases such as type 2 diabetes and atherosclerosis. On the basis of these, we studied previous papers which have been researched about the interaction between preadipocytes and macrophages, adipose tissues and lymph nodes, and adipose tissue secreting molecules. Results: Firstly, preadipocytes and macrophages are expressing similar transcriptomes and proteins, and preadipocytes can be converted to mature macrophages which have phagocytic activity. Moreover, the monocytes, which initially located in the bone marrow, are filtrated to the adipose tissue by monocyte chemotatic protein-1 and are matured to macrophages by colony stimulating factor-1. Secondly, adipose tissues and their associated lymph nodes are interacting each other in terms of energy efficiency. Lymph nodes promote lipolysis in adipose tissues, and polyunsaturated fatty acids in adipocytes become energy sources for dendritic cells. Lastly, adipose tissues produce and secrete proinflammatory molecules such as leptin, adiponectin, TNF-${\alpha}$, IL-6, and acute phase proteins, which induce the inflammation and potentially generate metabolic diseases. Conclusion: According to these, we can link adipose tissues to inflammation, but we need to affirm the actual levels and roles of adipose tissue-derived proinflammatory molecules in human body.

• Asian-Australasian Journal of Animal Sciences
• /
• 제14권12호
• /
• pp.1670-1674
• /
• 2001

To understand molecular mechanisms that regulate deposition and release of intramuscular fat, a fasting-induced clone was identified by differential screening from cDNA library of adipose tissues of Korean cattle. The clone had a total length of 1,319 nucleotides coding for 334 amino acids. It was identified as one encoding L-lactate dehydrogenase H chain (LDH-B). Comparison of the deduced amino acid sequences of bovine LDH-B with those of pig, human, rat, and mouse showed 98%, 98%, 97%, and 96% identity, respectively. Food deprivation for 48 h increased mRNA levels of LDH-B gene in adipose tissues of Korean cattle compared to fed- and 6 h refed- tissues. The expression of obese mRNA was examined for individual adipose tissue from several fat depots. Fasting induced expression of LDH-B gene in subcutaneous adipose tissues, but it did not affect expression levels in abdominal, perirenal and intramuscular tissues. Results demonstrate that induction of LDH-B gene during fasting may represent a metabolic shift from anaerobic state to aerobic predominance in fasted adipose tissues and that its responses to fasting are different among several adipose tissues.

• Nutrition Research and Practice
• /
• 제14권6호
• /
• pp.553-567
• /
• 2020

Vitamin D insufficiency is associated with obesity and its related metabolic diseases. Adipose tissues store and metabolize vitamin D and expression levels of vitamin D metabolizing enzymes are known to be altered in obesity. Sequestration of vitamin D in large amount of adipose tissues and low vitamin D metabolism may contribute to the vitamin D inadequacy in obesity. Vitamin D receptor is expressed in adipose tissues and vitamin D regulates multiple aspects of adipose biology including adipogenesis as well as metabolic and endocrine function of adipose tissues that can contribute to the high risk of metabolic diseases in vitamin D insufficiency. We will review current understanding of vitamin D regulation of adipose biology focusing on vitamin D modulation of adiposity and adipose tissue functions as well as the molecular mechanisms through which vitamin D regulates adipose biology. The effects of supplementation or maintenance of vitamin D on obesity and metabolic diseases are also discussed.

• Molecules and Cells
• /
• 제37권5호
• /
• pp.365-371
• /
• 2014

Recent findings, notably on adipokines and adipose tissue inflammation, have revised the concept of adipose tissues being a mere storage depot for body energy. Instead, adipose tissues are emerging as endocrine and immunologically active organs with multiple effects on the regulation of systemic energy homeostasis. Notably, compared with other metabolic organs such as liver and muscle, various inflammatory responses are dynamically regulated in adipose tissues and most of the immune cells in adipose tissues are involved in obesity-mediated metabolic complications, including insulin resistance. Here, we summarize recent findings on the key roles of innate (neutrophils, macrophages, mast cells, eosinophils) and adaptive (regulatory T cells, type 1 helper T cells, CD8 T cells, B cells) immune cells in adipose tissue inflammation and metabolic dysregulation in obesity. In particular, the roles of natural killer T cells, one type of innate lymphocyte, in adipose tissue inflammation will be discussed. Finally, a new role of adipocytes as antigen presenting cells to modulate T cell activity and subsequent adipose tissue inflammation will be proposed.

• 한국발생생물학회지:발생과생식
• /
• 제20권3호
• /
• pp.197-205
• /
• 2016

Adipose tissue is one of the major endocrine gland. More recently, local production of steroids in adipocytes differentiated from mouse 3T3-L1 cell-line was reported. We hypothesized that rat adipocytes have steroidogenic machinery and the expression patterns of the components might be differentially regulated, depending on the distribution and sex. To verify this hypothesis, we collected the adipose tissues depot-and sex-specifically at postnatal day (PND) 30, and performed quantitative RT-PCRs. In overall aspects, the abundances of the transcripts were lower in the brown adipose of both sexes. $3{\beta}-HSD$ transcript levels in female abdominal and reproductive adipose, CYP17 transcript levels in female reproductive adipose, $17{\beta}-HSD$ transcript levels in female abdominal and reproductive adipose, and CYP19 transcript levels in female abdominal adipose were significantly lower than those of male counterparts. Similar to steroidogenic factors, the abundance of the $ER-{\alpha}$ transcripts were generally lower in the brown adipose of both sexes. $ER-{\beta}$ transcripts were more abundant in male white adipose depots than their female counterparts. The levels of LHR transcripts in female reproductive adipose were significantly higher than those of male counterpart. In conclusion, our study demonstrated that the expressions of steroidogenesis-related genes were depot- and sex-specifically occurred in the immature male and female rat adipose tissues. Our study suggested that the adipose tissues are not only targets but de novo synthesizing sites of sex steroid(s), though the synthesizing activities could be much less than in gonads. Further researches in this field will be helpful for understanding the adipose physiology and for medical application such as sex-specific steroid supplement therapies for older populations.

• Asian-Australasian Journal of Animal Sciences
• /
• 제13권3호
• /
• pp.300-306
• /
• 2000

This experiment was carried out to determine the contributions of acetate, glucose, amino acids and amino acid metabolites as carbon precursors for the incorporation of radioisotope, in intramuscular and subcutaneous adipose tissue and the effects of insulin on lipogenesis and adrenergic agent, norepinephrine on lipolysis in both tissues. The rate of incorporation of $C^{14}$ labelled acetate, glucose, leucine, isoleucine and ${\alpha}$-ketoisocaproic acid into adipose tissue has been measured in subcutaneous and intramuscular adipose tissues. The rate of incorporation was greater (p<0.05) from acetate than glucose in both subcutaneous and intramuscular adipose tissue and the rate of incorporation of carbon precursors into adipose tissues was greater in subcutaneous than in intramuscular adipose tissues. In comparison of amino acids, the rate was highest (p<0.05) with leucine followed by isoleucine and ${\alpha}$-ketoisocaproic acid in subcutaneous adipose tissue, in which there were no differences. Also, in intramuscular tissue, leucine was highest (p<0.05), and the rate of incorporation decreased in the same order. The rates of carbon precursor incorporation appeared to be higher in subcutaneous than in intramuscular tissue. For incorporation of radio-labelled acetate and glucose into intramuscular adipose tissue. preincubated for 48 hrs with insulin and IGF-1, insulin was the most effective to stimulate the incorporation of precursors in both substrates but there was no difference between insulin and IGF-1 in glucose incorporation. For glyceride-fatty acid synthesis, acetate was significantly (p<0.05) greater than glucose in both subcutaneous and intramuscular adipose tissue, and glyceride-glycerol synthesis was greater (p<0.05) for glucose than acetate in both adipose tissues. The rates of lipogenesis from both precursors were slightly greater in subcutaneous than intramuscular adipose tissue. There was significant (p<0.05) site effect in insulin treatment for glyceride-fatty acid synthesis. But there were no significance in control and norepinephrine. For glyceride-glycerol synthesis, there was no site effect caused by hormonal treatment. Insulin was the most effective (p<0.05) in glyceride fatty acid synthesis, while norepinephrine was the same as control. Compared with control, glyceride-glycerol synthesis from acetate in insulin treatment was significantly (p<0.05) low in subcutaneous, but high in intramuscular tissue. At the same time, in both tissues, it was lower in norepinephrine treatment than in control. Glyceride-glycerol synthesis from glucose was highest (p<0.05) in norepinephrine treatment followed by insulin although there was no significance between insulin and control. Lipolysis was not affected by insulin but was increased by norepinephrine when added to adipose tissue incubations in vitro. Rates of basal lipolysis were greater in subcutaneous adipose tissue than in intramuscular adipose tissue.

• Asian-Australasian Journal of Animal Sciences
• /
• 제17권8호
• /
• pp.1062-1068
• /
• 2004

Leptin has a major role in the regulation of food intake and energy homeostasis. In addition, leptin participates in many physiological functions including regulation of lipid metabolism. Bovine recombinant leptin protein was produced in E. coli cells in order to understand function of leptin in the regulation of lipid metabolism. The leptin expression vector was constructed in pGEX-4T-3 vector and transformed into E. coli BL21 cells. Expression of the GST-leptin fusion protein was induced with IPTG. The fusion protein was purified using glutathione sepharose 4B batch method, and the recombinant leptin was eluted after thrombin protease digestion. The effect of leptin on glucose transport was examined in the differentiated adipocytes of 3T3-L1 cells. Leptin had no effect on basal and insulin-stimulated glucose transport in 3T3-L1 cells (p>0.05). Effect of recombinant leptin on glucose and acetate transport was examined in adipose tissues of Korean cattle (Hanwoo). Insulin stimulated glucose transport in both intramuscular and subcutaneous adipose tissues (p<0.05), but leptin did not affect glucose transport in both adipose tissues (p>0.05). Insulin stimulated acetate transport in bovine adipose tissues (p<0.05), but leptin did not affect acetate transport (p>0.05). Northern and RT-PCR analyses showed that mRNA levels of uncoupling protein-2 were increased by leptin treatment in 3T3-L1 cells without statistical difference (p>0.05). In conclusion, bovine recombinant leptin did not affect glucose and acetate transport in both 3T3-L1 adipocytes and bovine adipose tissues, while it stimulates UCP-2 mRNA expression in 3T3-L1 cells.

• Asian-Australasian Journal of Animal Sciences
• /
• 제14권1호
• /
• pp.13-16
• /
• 2001

Bovine ${\beta}1$-adrenergic receptor (AR) cDNA was cloned using degenerative primers. Bovine ${\beta}1$-AR coded for 467 amino acids and the comparison of the deduced amino acid sequence with that of sheep showed 93.4% identity. Northern blot analysis indicated that transcript size for the bovine ${\beta}1$-AR was 3.6 kb in the adipose tissue. The expression level of three $\beta$-ARs (1, 2, and 3) in bovine abdominal, subcutaneous, and perirenal adipose tissues were examined using reverse transcription-polymerase chain reaction (RT-PCR), and the levels of ${\beta}1$- and ${\beta}3$-AR mRNA were found to be lower in the subcutaneous adipose tissue than in the abdominal and perirenal adipose tissues. These results suggest that the expression of $\beta$-ARs mRNA are differentially regulated among the adipose tissues.

• Asian-Australasian Journal of Animal Sciences
• /
• 제14권12호
• /
• pp.1696-1700
• /
• 2001

An experiment was conducted to examine the effect of different feeding levels of concentrate (85, 100 and 115%) and age (15, 18 and 24 month) on fatty acid synthetase (FAS) activities in the 4 locations of adipose tissues (intermuscular, ITER; intramuscular, ITRA; kidney, KIDN and subcutaneous, SUBC) of 36 Korean native cattle (Hanwoo) steers. Steers of 100% feeding group were fed the amount of concentrate to meet the daily nutrient requirements, and the steers of second and third groups were fed concentrates at the levels of 85% and 115% of that of control group, respectively, up to 18 month of age. Thereafter, the steers were fed ad libitum up to 24 month of age. Feeding level of concentrates tended to affect the FAS activity of various adipose tissues in Hanwoo steers of each age. The FAS activity of ITER adipose tissue had the decreasing trend as the age of steers advanced while those of ITRA and SUBC adipose tissues had the slightly increasing tendency with age. The FAS activity based on the pooled data increased with the feeding level of concentrates (115%) in which the activities from all 4 adipose depots were higher than those with the lowest (85%) feeding level. Similar trend was observed from the pooled data of feeding level of concentrates by age of steers in which the FAS activities for all 3 ages were increased with feeding levels of concentrates. But the response in the FAS activity to the feeding level varied with age.