[Adipose tissue as a therapeutic target in obesity]

Role of Flavonoids in The Interactions among Obesity, Inflammation, and Autophagy

Nowadays, obesity is considered as one of the main concerns for public health worldwide, since it encompasses up to 39% of overweight and 13% obese (WHO) adults. It develops because of the imbalance in the energy intake/expenditure ratio, which leads to excess nutrients and results in dysfunction of adipose tissue. The hypertrophy of adipocytes and the nutrients excess trigger the induction of inflammatory signaling through various pathways, among others, an increase in the expression of pro-inflammatory adipocytokines, and stress of the endoplasmic reticulum (ER). A better understanding of obesity and preventing its complications are beneficial for obese patients on two facets: treating obesity, and treating and preventing the pathologies associated with it. Hitherto, therapeutic itineraries in most cases are based on lifestyle modifications, bariatric surgery, and pharmacotherapy despite none of them have achieved optimal results. Therefore, diet can play an important role in the prevention of adiposity, as well as the associated disorders. Recent results have shown that flavonoids intake have an essential role in protecting against oxidative damage phenomena, and presents biochemical and pharmacological functions beneficial to human health. This review summarizes the current knowledge of the anti-inflammatory actions and autophagic flux of natural flavonoids, and their molecular mechanisms for preventing and/or treating obesity.

Chloral Hydrate Treatment Induced Apoptosis of Macrophages via Fas Signaling Pathway

BACKGROUND There are recent reports on several anesthetics that have anti-inflammatory and anti-infective effects apart from their uses for pain relief and muscle relaxation. Chloral hydrate is a clinical anesthetic drug and sedative that has also been reported to attenuate inflammatory response, but the mechanisms are not clearly understood. MATERIAL AND METHODS This study investigated the effect of chloral hydrate treatment on the apoptosis of macrophages and explored the underlying mechanisms. RAW264.7 macrophages were treated with various concentrations of chloral hydrate for various lengths of time. Morphological changes were observed under a light microscope and apoptosis was detected with annexin-V-FITC/PI double-staining assay, Hochest 33258 and DNA ladder assay, the expression of Fas/FasL was detected with a flow cytometer, and the Fas signaling pathway was assessed by Western blotting. RESULTS The results showed that chloral hydrate treatment induced the morphology of RAW264.7 macrophages to change shape from typical fusiform to round in a concentration- and time-dependent manner, and was finally suspended in the supernatant. For the induction of apoptosis, chloral hydrate treatment induced the apoptosis of RAW264.7 macrophages from early-to-late stage apoptosis in a concentration- and time-dependent manner. For the mechanism, chloral hydrate treatment induced higher expression of Fas on RAW264.7 macrophages, and was also associated with changes in the expression of proteins involved in Fas signaling pathways. CONCLUSIONS Chloral hydrate treatment can induce the apoptosis of RAW264.7 macrophages through the Fas signaling pathway, which may provide new options for adjunctive treatment of acute inflammation.

Maternal Plane of Nutrition during Late Gestation and Weaning Age Alter Angus × Simmental Offspring Longissimus Muscle Transcriptome and Intramuscular Fat

In model organisms both the nutrition of the mother and the young offspring could induce long-lasting transcriptional changes in tissues. In livestock, such changes could have important roles in determining nutrient use and meat quality. The main objective was to evaluate if plane of maternal nutrition during late-gestation and weaning age alter the offspring's Longissimus muscle (LM) transcriptome, animal performance, and metabolic hormones. Whole-transcriptome microarray analysis was performed on LM samples of early (EW) and normal weaned (NW) Angus × Simmental calves born to grazing cows receiving no supplement [low plane of nutrition (LPN)] or 2.3 kg high-grain mix/day [medium plane of nutrition (MPN)] during the last 105 days of gestation. Biopsies of LM were harvested at 78 (EW), 187 (NW) and 354 (before slaughter) days of age. Despite greater feed intake in MPN offspring, blood insulin was greater in LPN offspring. Carcass intramuscular fat content was greater in EW offspring. Bioinformatics analysis of the transcriptome highlighted a modest overall response to maternal plane of nutrition, resulting in only 35 differentially expressed genes (DEG). However, weaning age and a high-grain diet (EW) strongly impacted the transcriptome (DEG = 167), especially causing a lipogenic program activation. In addition, between 78 and 187 days of age, EW steers had an activation of the innate immune system due presumably to macrophage infiltration of intramuscular fat. Between 187 and 354 days of age (the "finishing" phase), NW steers had an activation of the lipogenic transcriptome machinery, while EW steers had a clear inhibition through the epigenetic control of histone acetylases. Results underscored the need to conduct further studies to understand better the functional outcome of transcriptome changes induced in the offspring by pre- and post-natal nutrition. Additional knowledge on molecular and functional outcomes would help produce more efficient beef cattle.

Estrogen signaling in metabolic inflammation

There is extensive evidence supporting the interference of inflammatory activation with metabolism. Obesity, mainly visceral obesity, is associated with a low-grade inflammatory state, triggered by metabolic surplus where specialized metabolic cells such as adipocytes activate cellular stress initiating and sustaining the inflammatory program. The increasing prevalence of obesity, resulting in increased cardiometabolic risk and precipitating illness such as cardiovascular disease, type 2 diabetes, fatty liver, cirrhosis, and certain types of cancer, constitutes a good example of this association. The metabolic actions of estrogens have been studied extensively and there is also accumulating evidence that estrogens influence immune processes. However, the connection between these two fields of estrogen actions has been underacknowledged since little attention has been drawn towards the possible action of estrogens on the modulation of metabolism through their anti-inflammatory properties. In the present paper, we summarize knowledge on the modification inflammatory processes by estrogens with impact on metabolism and highlight major research questions on the field. Understanding the regulation of metabolic inflammation by estrogens may provide the basis for the development of therapeutic strategies to the management of metabolic dysfunctions.

Adiposopathy, "sick fat," Ockham's razor, and resolution of the obesity paradox

Among lean populations, cardiovascular disease (CVD) is rare. Among those with increased adiposity, CVD is the commonest cause of worldwide death. The "obesity paradox" describes seemingly contrary relationships between body fat and health/ill-health. Multiple obesity paradoxes exist, and include the anatomic obesity paradox, physiologic obesity paradox, demographic obesity paradox, therapeutic obesity paradox, cardiovascular event/procedure obesity paradox, and obesity treatment paradox. Adiposopathy ("sick fat") is defined as adipocyte/adipose tissue dysfunction caused by positive caloric balance and sedentary lifestyle in genetically and environmentally susceptible individuals. Adiposopathy contributes to the commonest metabolic disorders encountered in clinical practice (high glucose levels, high blood pressure, dyslipidemia, etc.), all major CVD risk factors. Ockham's razor is a principle of parsimony which postulates that among competing theories, the hypothesis with the fewest assumptions is the one best selected. Ockham's razor supports adiposopathy as the primary cause of most cases of adiposity-related metabolic diseases, which in turn helps resolve the obesity paradox.

Brazilein from Caesalpinia sappan L. Antioxidant Inhibits Adipocyte Differentiation and Induces Apoptosis through Caspase-3 Activity and Anthelmintic Activities against Hymenolepis nana and Anisakis simplex

Brazilein, a natural, biologically active compound from Caesalpinia sappan L., has been shown to exhibit anti-inflammatory and antioxidant properties and to inhibit the growth of several cancer cells. This study verifies the antioxidant and antitumor characteristics of brazilein in skin cancer cells and is the first time to elucidate the inhibition mechanism of adipocyte differentiation, cestocidal activities against Hymenolepis nana, and reduction of spontaneous movement in Anisakis simplex. Brazilein exhibits an antioxidant capacity as well as the ability to scavenge DPPH^• and ABTS^•+ free radicals and to inhibit lipid peroxidation. Brazilein inhibited intracellular lipid accumulation during adipocyte differentiation in 3T3-L1 cells and suppressed the induction of peroxisome proliferator-activated receptor γ (PPARγ), the master regulator of adipogenesis, suggesting that brazilein presents the antiobesity effects. The toxic effects of brazilein were evaluated in terms of cell viability, induction of apoptosis, and the activity of caspase-3 in BCC cells. The inhibition of the growth of skin cancer cells (A431, BCC, and SCC25) by brazilein is greater than that of human skin malignant melanoma (A375) cells, mouse leukemic monocyte macrophage (RAW 264.7 cells), and noncancerous cells (HaCaT and BNLCL2 cells). The anthelmintic activities of brazilein against Hymenolepis nana are better than those of Anisakis simplex.

Chronic inflammation in obesity and the metabolic syndrome

The increasing incidence of obesity and the metabolic syndrome is disturbing. The activation of inflammatory pathways, used normally as host defence, reminds the seriousness of this condition. There is probably more than one cause for activation of inflammation. Apparently, metabolic overload evokes stress reactions, such as oxidative, inflammatory, organelle and cell hypertrophy, generating vicious cycles. Adipocyte hypertrophy, through physical reasons, facilitates cell rupture, what will evoke an inflammatory reaction. Inability of adipose tissue development to engulf incoming fat leads to deposition in other organs, mainly in the liver, with consequences on insulin resistance. The oxidative stress which accompanies feeding, particularly when there is excessive ingestion of fat and/or other macronutrients without concomitant ingestion of antioxidant-rich foods/beverages, may contribute to inflammation attributed to obesity. Moreover, data on the interaction of microbiota with food and obesity brought new hypothesis for the obesity/fat diet relationship with inflammation. Beyond these, other phenomena, for instance psychological and/or circadian rhythm disturbances, may likewise contribute to oxidative/inflammatory status. The difficulty in the management of obesity/metabolic syndrome is linked to their multifactorial nature where environmental, genetic and psychosocial factors interact through complex networks.