Esterification of free fatty acids in adipocytes: a comparison between octanoate and oleate

2000 ◽  
Vol 349 (2) ◽  
pp. 463-471 ◽  
Author(s):  
Wen GUO ◽  
Ji-Kyung CHOI ◽  
James L. KIRKLAND ◽  
Barbara E. CORKEY ◽  
James A. HAMILTON

Medium-chain triacylglycerols (MCT) are present in milk, coconut oil and other foods, and are used therapeutically in special diets for certain disorders of lipid and glucose utilization. Recently, it has become apparent that MCT are not only oxidized in the liver, but are also present in lymph and fat tissue, particularly after chronic treatment. To evaluate the influence of MCT on metabolism in fat cells, we compared incorporation of octanoate and oleate into cellular triacylglycerols of 3T3-L1 adipocytes as well as their effects on preadipocyte differentiation. We found that less octanoate than oleate was stored and that more octanoate than oleate was oxidized. Octanoate was esterified to a greater extent at the sn-1,3 position of glyceryl carbons than at the sn-2 position, whereas the opposite was true for oleate. Glycerol release from fat cells pre-treated with octanoate was also greater than from cells pre-treated with oleate, presumably related to the preferential release of octanoate from the sn-1,3 position. Octanoate was not incorporated into lipids in undifferentiated cells and did not induce differentiation in these cells, whereas oleate was readily stored and actually induced differentiation. Incorporation of octanoate into lipids increased as cells differentiated, but reached a maximum of about 10% of the total stored fatty acids. If these effects in vitro also occur in vivo, substitution of octanoate for oleate or other long-chain fatty acids could have the beneficial effect of diminishing fat-cell number and lipid content.

2021 ◽  
Vol 22 (10) ◽  
pp. 5363
Author(s):  
Isabel C. Cohen ◽  
Emry R. Cohenour ◽  
Kristen G. Harnett ◽  
Sonya M. Schuh

Bisphenol A (BPA) is an endocrine-disrupting chemical used in the production of plastics, and is linked to developmental, reproductive, and metabolic disorders including obesity. Manufacturers have begun using ‘BPA-free’ alternatives instead of BPA in many consumer products. However, these alternatives have had much less testing and oversight, yet they are already being mass-produced and used across industries from plastics to food-contact coatings. Here, we used human female adipose-derived stem cells (hASCs), a type of adult mesenchymal stem cell, to compare the effects of BPA and BPA alternatives on adipogenesis or fat cell development in vitro. We focused on two commonly used BPA replacements, bisphenol AF (BPAF) and tetramethyl bisphenol F (TMBPF; monomer of the new valPure V70 food-contact coating). Human ASCs were differentiated into adipocytes using chemically defined media in the presence of control differentiation media with and without 17β-estradiol (E2; 10 μM), or with increasing doses of BPA (0, 0.1 and 1 μM), BPAF (0, 0.1, 1 and 10 nM), or TMBPF (0, 0.01 and 0.1 μM). After differentiation, the cells were stained and imaged to visualize and quantify the accumulation of lipid vacuoles and number of developing fat cells. Treated cells were also examined for cell viability and apoptosis (programmed cell death) using the respective cellular assays. Similar to E2, BPA at 0.1 μM and BPAF at 0.1 nM, significantly increased adipogenesis and lipid production by 20% compared to control differentiated cells (based on total lipid vacuole number to cell number ratios), whereas higher levels of BPA and BPAF significantly decreased adipogenesis (P < 0.005). All tested doses of TMBPF significantly reduced adipogenesis and lipid production by 30–40%, likely at least partially through toxic effects on stem cells, as viable cell numbers decreased and apoptosis levels increased throughout differentiation. These findings indicate that low, environmentally-relevant doses of BPA, BPAF, and TMBPF have significant effects on fat cell development and lipid accumulation, with TMBPF having non-estrogenic, anti-adipogenic effects. These and other recent results may provide a potential cellular mechanism between exposure to bisphenols and human obesity, and underscore the likely impact of these chemicals on fat development in vivo.


1995 ◽  
Vol 311 (1) ◽  
pp. 327-331 ◽  
Author(s):  
M L Bonet ◽  
F Serra ◽  
J C Matamala ◽  
F J García-Palmer ◽  
A Palou

The relative stability against a decrease in adrenergic stimulation of the uncoupling protein (UCP) incorporated into different mitochondrial fractions was investigated in brown-fat-cell cultures. Cultures were initiated with undifferentiated cells from young mice and were acutely stimulated with noradrenaline at confluence (day 7). Cells were harvested just after the finish of the 24 h stimulation treatment or 24 h later, and three mitochondrial fractions were isolated by differential centrifugation: the M1 fraction (1000 g), the M3 fraction (3000 g) and the M15 fraction (15,000 g). The results obtained in vitro indicate that removal of adrenergic stimulation determines a selective loss of UCP from the lightest mitochondrial fractions (M3 and M15). Similar results were obtained in a situation in vivo (24 h starvation in mice) which is known to lead to a decreased noradrenaline input to brown adipose tissue, with decreased UCP levels. Thus brown adipocytes possess different mitochondrial subpopulations, which exhibit characteristic changes in their UCP turnover in response to thermogenic signals.


Diabetes ◽  
2018 ◽  
Vol 67 (Supplement 1) ◽  
pp. 92-OR ◽  
Author(s):  
WEI HUANG ◽  
YONG XU ◽  
YOUHUA XU ◽  
LUPING ZHOU ◽  
CHENLIN GAO

Coronaviruses ◽  
2020 ◽  
Vol 01 ◽  
Author(s):  
Ashraf Talaat Youssef

The pandemic of COVID-19 had started in Wuhan city china in late 2019 with a subsequent worldwide spread. The viral infection can seriousely affect multiple organs mainly lungs, kidneys, heart, liver and brain and may lead to respiratory, renal, cardiac or hepatic failure.Vascular thrombosis of unexplained mechanism that may lead to widespread blood clots in multiple organs and cytokine storms that result of overstimulation of the immune system subsequent of lung damage may lead to sudden decompensation due to hypotension and more damage to liver, kidney, brain or lungs.Until now no drug had proved efficient in getting rid of the problem and controlling the pandemic mainly depends on preventive measures.Many preventive measures can be considered to prevent the worldwide spread of viral transmission. Polyunsaturated long chain fatty acids (PUFAs) and the medium chain saturated fatty acids (MCSFAs) and their corresponding monoglycerides had high antiviral activities against the enveloped viruses which reach to more than 10,000 -fold reduction in the viral titres in vitro and in vivo after testing of its gastric aspirate, and can contribute to the systemic immunity against the enveloped viruses.


Development ◽  
1988 ◽  
Vol 102 (4) ◽  
pp. 793-803 ◽  
Author(s):  
V.E. Papaioannou ◽  
K.M. Ebert

Total cell number as well as differential cell numbers representing the inner cell mass (ICM) and trophectoderm were determined by a differential staining technique for preimplantation pig embryos recovered between 5 and 8 days after the onset of oestrus. Total cell number increased rapidly over this time span and significant effects were found between embryos of the same chronological age from different females. Inner cells could be detected in some but not all embryos of 12–16 cells. The proportion of inner cells was low in morulae but increased during differentiation of ICM and trophectoderm in early blastocysts. The proportion of ICM cells then decreased as blastocysts expanded and hatched. Some embryos were cultured in vitro and others were transferred to the oviducts of immature mice as a surrogate in vivo environment and assessed for morphology and cell number after several days. Although total cell number did not reach in vivo levels, morphological development and cell number increase was sustained better in the immature mice than in vitro. The proportion of ICM cells in blastocysts formed in vitro was in the normal range.


Development ◽  
1977 ◽  
Vol 41 (1) ◽  
pp. 79-92
Author(s):  
Rosita Smith ◽  
Anne McLaren

In normal mouse embryos developing in vivo, the first appearance of the blastocyst cavity was found to be associated more closely with developmental age, judged by cell number, than with chronological age, i.e. elapsed time since ovulation. When development was slowed by in vitro culture, formation of the blastocoele was delayed. However, cell number itself was not a critical factor, since the number of cells per embryo could be doubled or tripled or halved by experimental manipulation without substantially affecting the timing of blastocoele formation. Experiments in which one cell division was suppressed with cytochalasin-B, leading to tetraploidy, showed that the number of cell divisions since fertilization was also not critical. A possible role is suggested either for nucleocytoplasmic ratio, or for the number of nuclear or chromosomal divisions or DNA replications since fertilization, all of which increase during cleavage.


Development ◽  
1981 ◽  
Vol 61 (1) ◽  
pp. 277-287
Author(s):  
A. J. Copp

The number of trophoblast giant cells in outgrowths of mouse blastocysts was determined before, during and after egg-cylinder formation in vitro. Giant-cell numbers rose initially but reached a plateau 12 h before the egg cylinder appeared. A secondary increase began 24 h after egg-cylinder formation. Blastocysts whose mural trophectoderm cells were removed before or shortly after attachment in vitro formed egg cylinders at the same time as intact blastocysts but their trophoblast outgrowths contained fewer giant cells at this time. The results support the idea that egg-cylinder formation in vitro is accompanied by a redirection of the polar to mural trophectoderm cell movement which characterizes blastocysts before implantation. The resumption of giant-cell number increase in trophoblast outgrowths after egg-cylinder formation may correspond to secondary giant-cell formation in vivo. It is suggested that a time-dependent change in the strength of trophoblast cell adhesion to the substratum occurs after blastocyst attachment in vitro which restricts the further entry of polar cells into the outgrowth and therefore results in egg-cylinder formation.


2020 ◽  
Author(s):  
Fangxian Liu ◽  
Qijin Pan ◽  
Liangliang Wang ◽  
Shijiang Yi ◽  
Peng Liu ◽  
...  

Abstract Background: Calycosin is a naturally-occurring phytoestrogen that reportedly exerts anti- nasopharyngeal carcinoma (NPC) effects. Nevertheless, the molecular mechanisms for anti-NPC using calycosin remain unrevealed. Methods: Thus, a network pharmacology was used to uncover anti-NPC pharmacological targets and mechanisms of calycosin. Additionally, validated experiments were conducted to validate the bioinformatic findings of calycosin for treating NPC. Results: As results, bioinformatic assays showed that the predictive pharmacological targets of calycosin against NPC were TP53, MAPK14, CASP8, MAPK3, CASP3, RIPK1, JUN, ESR1, respectively. And the top 20 biological processes and pharmacological mechanisms of calycosin against NPC were identified accordingly. In clinical data, NPC samples showed positive expression of MAPK14, reduced TP53, CASP8 expressions. In studies in vitro and in vivo, calycosin-dosed NPC cells resulted in reduced cell proliferation, promoted cell apoptosis. In TUNEL staining, calycosin exhibited elevated apoptotic cell number. And immunostaining assays resulted in increased TP53, CASP8 positive cells, and reduced MAPK14 expressions in calycosin-dosed NPC cells and tumor-bearing nude mice. Conclusion: Altogether, these bioinformatic findings reveal optimal pharmacological targets and mechanisms of calycosin against NPC, following with representative identification of human and preclinical experiments. Notably, some of original biotargets may be potentially used to treat NPC.


2021 ◽  
Author(s):  
Qiong Wang ◽  
Guan Wang ◽  
Gaoyan Li ◽  
Anying Song ◽  
Wenting Dai ◽  
...  

Abstract The average fat mass in adults increases dramatically with age, and older people often suffer from visceral obesity and related adverse metabolic disorders. Unfortunately, how aging leads to fat accumulation is poorly understood. It is known that fat cell (adipocyte) turnover is very low in young mice, similar to that in young humans. Here, we find that mice mimic age-related fat expansion in humans. In vivo lineage tracing shows that massive adipogenesis (the generation of new adipocytes), especially in the visceral fat, is triggered during aging. Thus, in contrast to most types of adult stem cells that exhibit a reduced ability to proliferate and differentiate, the adipogenic potential of adipocyte progenitor cells (APCs) is unlocked by aging. In vivo transplantation and 3D imaging of transplants show that APCs in aged mice cell-autonomously gain high adipogenic capacity. Single-cell RNA sequencing analyses reveal that aging globally remodels APCs. Herein, we identify a novel committed preadipocyte population that is age-specific (CP-A), existing both in mice and humans, with a global activation of proliferation and adipogenesis pathways. CP-A cells display high proliferation and adipogenesis activity, both in vivo and in vitro. Macrophages may regulate the remodeling of APCs and the generation of CP-A cells during aging. Together, these findings define a new fundamental mechanism involved in fat tissue aging and offer prospects for preventing and treating age-related metabolic disorders.


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