Two ideals connected with strong right upper porosity at a point

Let $SP$ be the set of upper strongly porous at $0$ subsets of $\mathbb R^{+}$ and let $\hat I(SP)$ be the intersection of maximal ideals $I \subseteq SP$. Some characteristic properties of sets $E\in\hat I(SP)$ are obtained. It is shown that the ideal generated by the so-called completely strongly porous at $0$ subsets of $\mathbb R^{+}$ is a proper subideal of $\hat I(SP).$Comment: 18 page

Postexercise changes in myocellular lipid droplet characteristics of young lean individuals are affected by circulatory nonesterified fatty acids

Intramyocellular lipid (IMCL) content is an energy source during acute exercise. Nonesterified fatty acid (NEFA) levels can compete with IMCL utilization during exercise. IMCL content is stored as lipid droplets (LDs) that vary in size, number, subcellular distribution, and in coating with LD protein PLIN5. Little is known about how these factors are affected during exercise and recovery. Here, we aimed to investigate the effects of acute exercise with and without elevated NEFA levels on intramyocellular LD size and number, intracellular distribution and PLIN5 coating, using high-resolution confocal microscopy. In a crossover study, 9 healthy lean young men performed a 2-h moderate intensity cycling protocol in the fasted (high NEFA levels) and glucose-fed state (low NEFA levels). IMCL and LD parameters were measured at baseline, directly after exercise and 4 h postexercise. We found that total IMCL content was not changed directly after exercise (irrespectively of condition), but IMCL increased 4 h postexercise in the fasting condition, which was due to an increased number of LDs rather than changes in size. The effects were predominantly detected in type I muscle fibers and in LDs coated with PLIN5. Interestingly, subsarcolemmal, but not intermyofibrillar IMCL content, was decreased directly after exercise in the fasting condition and was replenished during the 4 h recovery period. In conclusion, acute exercise affects IMCL storage during exercise and recovery, particularly in type I muscle fibers, in the subsarcolemmal region and in the presence of PLIN5. Moreover, the effects of exercise on IMCL content are affected by plasma NEFA levels.NEW & NOTEWORTHY Skeletal muscle stores lipids in lipid droplets (LDs) that can vary in size, number, and location and are a source of energy during exercise. Specifically, subsarcolemmal LDs were used during exercise when fasted. Exercising in the fasted state leads to postrecovery elevation in IMCL levels due to an increase in LD number in type I muscle fibers, in subsarcolemmal region and decorated with PLIN5. These effects are blunted by glucose ingestion during exercise and recovery

Reduced incorporation of Fatty acids into triacylglycerol in myotubes from obese individuals with type 2 diabetes.

Altered skeletal muscle lipid metabolism is a hallmark feature of type 2 (T2D). Here we investigated muscle lipid turnover in T2D versus BMI- controls and examined if putative in vivo differences would be preserved myotubes.Male obese T2D individuals (T2D) (n=6) and their BMI-matched (C) (n=6) underwent a hyperinsulinemic-euglycemic clamp, VO2max test, underwater weighing and muscle biopsy of v. lateralis. 14C-palmitate and 14C-oleate oxidation rates and incorporation into lipids were measured tissue, as well as in primary myotubes.Palmitate oxidation (C: 0.99 +/- T2D: 0.53 +/- 0.07nmol/mg protein; P=0.03) and incorporation of fatty into triacylglycerol (TAG) (C: 0.45 +/- 0.13, T2D: 0.11 +/- 0.02nmol/mg P=0.047) were significantly reduced in muscle homogenates of T2D. These reductions were not retained for palmitate oxidation in primary myotubes (P=0.38); however, incorporation of FAs into TAG was lower in T2D oleate and P=0.11 for palmitate), with a strong correlation of TAG between muscle tissue and primary myotubes (r=0.848, P=0.008).Our data that the ability to incorporate FAs into TAG is an intrinsic feature of muscle cells that is reduced in individuals with T2D

Exercise-induced modulation of cardiac lipid content in healthy lean young men

Cardiac lipid accumulation is associated with decreased cardiac function and energy status (PCr/ATP). It has been suggested that elevated plasma fatty acid (FA) concentrations are responsible for the cardiac lipid accumulation. Therefore, the aim of the present study was to investigate if elevating plasma FA concentrations by exercise results in an increased cardiac lipid content, and if this influences cardiac function and energy status. Eleven male subjects (age 25.4 ± 1.1 years, BMI 23.6 ± 0.8 kg/m2) performed a 2-h cycling protocol, once while staying fasted and once while ingesting glucose, to create a state of high versus low plasma FA concentrations, respectively. Cardiac lipid content was measured by proton magnetic resonance spectroscopy (1H-MRS) at baseline, directly after exercise and again 4 h post-exercise, together with systolic function (by multi-slice cine-MRI) and cardiac energy status (by 31P-MRS). Plasma FA concentrations were increased threefold during exercise and ninefold during recovery in the fasted state compared with the glucose-fed state (p < 0.01). Cardiac lipid content was elevated at the end of the fasted test day (from 0.26 ± 0.04 to 0.44 ± 0.04%, p = 0.003), while it did not change with glucose supplementation (from 0.32 ± 0.03 to 0.26 ± 0.05%, p = 0.272). Furthermore, PCr/ATP was decreased by 32% in the high plasma FA state compared with the low FA state (n = 6, p = 0.014). However, in the high FA state, the ejection fraction 4 h post-exercise was higher compared with the low FA state (63 ± 2 vs. 59 ± 2%, p = 0.018). Elevated plasma FA concentrations, induced by exercise in the fasted state, lead to increased cardiac lipid content, but do not acutely hamper systolic function. Although the lower cardiac energy status is in line with a lipotoxic action of cardiac lipid content, a causal relationship cannot be proven

Calorie restriction-like effects of 30 days of resveratrol supplementation on energy metabolism and metabolic profile in obese humans

Resveratrol is a natural compound that affects energy metabolism and mitochondrial function and serves as a calorie restriction mimetic, at least in animal models of obesity. Here we treated 11 healthy, obese men with placebo and 150 mg/day resveratrol in a randomized double-blind cross-over study for 30 days. Resveratrol significantly reduced sleeping- and resting metabolic rate. In muscle, resveratrol activated AMPK, increased SIRT1 and PGC-1α protein levels, increased citrate synthase activity without change in mitochondrial content, and improved muscle mitochondrial respiration on a fatty acid-derived substrate. Furthermore, resveratrol elevated intramyocellular lipid levels, and decreased intrahepatic lipid content, circulating glucose, triglycerides, alanine-aminotransferase, and inflammation markers. Systolic blood pressure dropped and HOMA index improved after resveratrol. In the postprandial state, adipose tissue lipolysis and plasma fatty acid and glycerol decreased. In conclusion, we demonstrate that 30 days of resveratrol supplementation induces metabolic changes in obese humans, mimicking the effects of calorie restriction

Causes and consequences of lipid overload in skeletal muscle, liver and heart

With obesity, fat begins to accumulate in tissues other than adipose tissue (ectopic fat accumulation). This can have adverse health effects (lipotoxicity) and is believed to play an important role in the development of chronic diseases such as diabetes. This dissertation examined why fat accumulates in ectopic tissues such as muscles, the liver and the heart, and the role free fatty acids play in this process. It also examined the effect of fat accumulation on organ function. The study found that, while free fatty acids play a key role in the accumulation of fat, fat accumulation does not always lead to organ dysfunction

Acute exercise does not decrease liver fat in men with overweight or NAFLD

Elevated hepatic lipid content (IntraHepatic Lipid, IHL) increases the metabolic complications. Although prolonged exercise training lowers unknown if acute exercise has the same effect. Furthermore, hepatic ATP may be related to insulin resistance and IHL. We aimed to investigate if exercise leads to changes in IHL and whether this is accompanied by hepatic ATP. Twenty-one men (age 54.8 +/- 7.2 years, BMI 29.7 +/- 2.2 performed a 2 h cycling protocol, once while staying fasted and once ingesting glucose. IHL was determined at baseline, 30 min post-exercise post-exercise. Additionally ATP/Total P ratio was measured at baseline post-exercise. Compared with baseline values we did not observe any significant changes in IHL within 30 min post-exercise in neither the the glucose-supplemented condition. However, IHL was elevated 4 h post- compared with baseline in the fasted condition (from 8.3 +/- 1.8 to 8.7 p = 0.010), an effect that was blunted by glucose supplementation (from 1.9 to 8.3 +/- 1.9%, p = 0.789). Acute exercise does not decrease liver overweight middle-aged men. Moreover, IHL increased 4 h post-exercise in fasted condition, an increase that was absent in the glucose- condition. These data suggest that a single bout of exercise may not be lower IHL