We have recently demonstrated that palmitoleic acid (16:1n7) increases lipolysis, glucose uptake and glucose utilization for energy production in white adipose cells. In the present study, we tested ...the hypothesis that palmitoleic acid modulates bioenergetic activity in white adipocytes.
For this, 3 T3-L1 pre-adipocytes were differentiated into mature adipocytes in the presence (or absence) of palmitic (16:0) or palmitoleic (16:1n7) acid at 100 or 200 μM. The following parameters were evaluated: lipolysis, lipogenesis, fatty acid (FA) oxidation, ATP content, oxygen consumption, mitochondrial mass, citrate synthase activity and protein content of mitochondrial oxidative phosphorylation (OXPHOS) complexes.
Treatment with 16:1n7 during 9 days raised basal and isoproterenol-stimulated lipolysis, FA incorporation into triacylglycerol (TAG), FA oxidation, oxygen consumption, protein expression of subunits representing OXPHOS complex II, III, and V and intracellular ATP content. These effects were not observed in adipocytes treated with 16:0.
Palmitoleic acid, by concerted action on lipolysis, FA esterification, mitochondrial FA oxidation, oxygen consumption and ATP content, does enhance white adipocyte energy expenditure and may act as local hormone.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Objective
The study goal was to analyze the effects of a high‐fat diet (HFD) on the histone 3 lysine 27 (H3K27) posttranscriptional modifications and the expression of histone‐modifying enzymes in ...adipose‐derived stromal cells (ASCs) from white adipose tissue (WAT).
Methods
Male C57BL/6J mice received control or HFD for 12 weeks. The ASCs were isolated from subcutaneous and visceral (epididymal) WAT, cultivated, and evaluated for expression of H3K27 trimethylation (H3K27me3) and H3K27 acetylation (H3K27ac) by Western blot. The transcription of histone‐modifying enzymes was analyzed by real‐time polymerase chain reaction.
Results
When compared with control, HFD ASCs showed a decrease in H3K27ac enrichment in subcutaneous and visceral WAT and ATP‐citrate lyase expression in subcutaneous WAT. Curiously, the expression of CREB‐binding protein was increased in visceral ASCs from HFD‐fed mice.
Conclusions
These results show that an HFD significantly reduces acetylation of H3K27 in ASCs and the expression of ATP‐citrate lyase in subcutaneous ASCs, suggesting that, in this fat depot, the H3K27ac reduction could be partly due to lower acetyl‐coenzyme A availability. H3K27ac is an epigenetic mark responsible for increasing the transcription rate and its reduction can have an important impact on ASC proliferation and differentiation potential.
Key points
Fish oil (FO), rich in omega‐3 polyunsaturated fatty acids, has beneficial effects on changes induced by obesity and partially prevents associated comorbidities.
The effects of FO on ...adipocytes from different adipose tissue depots in high‐fat (HF) diet induced obese mice have not been uninvestigated.
This is the first study to examine the effects of FO on changes in metabolism and adipokine production in adipocytes from s.c. (inguinal; ING) or visceral (retroperitoneal; RP) white adipose depots in a HF diet‐induced obese mice.
Unlike most studies performed previously, FO supplementation was initiated 4 weeks before the induction of obesity.
HF diet caused marked changes in ING (glucose uptake and secretion of adiponectin, tumour necrosis factor‐α and interleukin‐6 in ING) and RP (lipolysis, de novo lipogenesis and secretion of pro‐inflammatory cytokines) adipose depots.
Previous and concomitant FO administration prevented the changes in ING and RP adipocytes induced by the HF diet.
In the present study, we investigated the effect of fish oil (FO) on metabolism and adipokine production by adipocytes from s.c. (inguinal; ING) and visceral (retroperitoneal; RP) white adipose depots in high‐fat (HF) diet‐induced obese mice. Mice were divided into CO (control diet), CO+FO, HF and HF+FO groups. The HF group presented higher body weight, glucose intolerance, insulin resistance, higher plasma total and low‐density lipoprotein cholesterol levels, and greater weights of ING and RP adipose depots accompanied by hypertrophy of the adipocytes. FO exerted anti‐obesogenic effects associated with beneficial effects on dyslipidaemia and insulin resistance in mice fed a HF diet (HF+FO group). HF raised RP adipocyte lipolysis and the production of pro‐inflammatory cytokines and reduced de novo synthesis of fatty acids, whereas, in ING adipocytes, it decreased glucose uptake and adiponectin secretion but did not change lipolysis. Therefore, the adipose depots play different roles in HF diet‐induced insulin resistance according to their location in the body. Concerning cytokine secretion, adipocytes per se in addition to white adopise tissue infiltrated leukocytes have to be considered in the aetiology of the comorbidities associated with obesity. Evidence is presented showing that previous and concomitant administration of FO can prevent changes in metabolism and the secretion of hormones and cytokines in ING and RP adipocytes induced by HF.
Key points
Fish oil (FO), rich in omega‐3 polyunsaturated fatty acids, has beneficial effects on changes induced by obesity and partially prevents associated comorbidities.
The effects of FO on adipocytes from different adipose tissue depots in high‐fat (HF) diet induced obese mice have not been uninvestigated.
This is the first study to examine the effects of FO on changes in metabolism and adipokine production in adipocytes from s.c. (inguinal; ING) or visceral (retroperitoneal; RP) white adipose depots in a HF diet‐induced obese mice.
Unlike most studies performed previously, FO supplementation was initiated 4 weeks before the induction of obesity.
HF diet caused marked changes in ING (glucose uptake and secretion of adiponectin, tumour necrosis factor‐α and interleukin‐6 in ING) and RP (lipolysis, de novo lipogenesis and secretion of pro‐inflammatory cytokines) adipose depots.
Previous and concomitant FO administration prevented the changes in ING and RP adipocytes induced by the HF diet.
We recently demonstrated that palmitoleic acid (C16:1n7), a monounsaturated fatty acid, increases the metabolic and oxidative capacity of 3T3-L1 adipocytes. Herein, the effect of 16:1n7 ...supplementation on metabolic parameters on white adipose tissue (WAT) and liver of obese mice induced by a high-fat diet (HFD) was addressed by analyzing metabolic (dys)function and altered genes expression in adipose tissue, as well as liver and serum biochemistry analysis. For this purpose, mice were induced to obesity for 8 weeks, and from the 5th week, they received 16:1n7 (300 mg/kg per day) or water for 30 days, by gavage. Subcutaneous inguinal (ING) and epididymal (EPI) WAT were removed for analysis of metabolic, (anti)inflammatory, adipogenic, and thermogenic genes expression by real-time reverse transcriptase-polymerase chain reaction. Additionally, metabolic activities of isolated adipocytes, such as glucose uptake, lipogenesis (triacylglycerol esterification), β-oxidation, and lipolysis in ING adipocytes, were also assessed. Despite the higher fat intake, the HFD group showed lower food intake but higher body weight, increased glucose, significant dyslipidemia, and increased liver and adipose depot mass, accompanied by liver steatosis. The 16:1n7 supplementation slowed down the body mass gain and prevented the increase of lipids in the liver. HFD+n7 animals presented increased fatty acid oxidation and lipogenesis compared to control, but no effect was observed on lipolysis and glucose uptake in ING isolated adipocytes. Besides, 16:1n7 increased the content of the mRNA encoding FABP4, but partially prevented the expression of genes encoding ATGL, HSL, perilipin, lipin, C/EBP-α, PPAR-γ, C/EBP-β, CPT1, NRF1, TFAM, PRDM16, and nitric oxide synthase 2 in ING depot from HFD group of animals. Finally, HFD increased
and
α expression, and 16:1n7 promoted a more marked increase in it. In summary, the data show that palmitoleic acid promotes metabolic changes and partially prevents the increase in gene expression on adipocytes triggered by obesity, suggesting that HFD+n7 animals do not require the same magnitude of metabolic adaptation to cope with energy demand from the HFD. In the long term, the effects of 16:1n7 may be more evident and beneficial for the function/dysfunction of WAT from an obese organism, with relevant repercussions in the systemic metabolic homeostasis.
The effect of fish oil (FO) treatment on high‐fat (HF) diet‐induced obesity and metabolic syndrome was addressed by analyzing dysfunctions in cells of different adipose depots. For this purpose, mice ...were initially induced to obesity for 8 weeks following a treatment with FO containing high concentration of EPA compared to DHA (5:1), for additional 8 weeks (by gavage, 3 times per week). Despite the higher fat intake, the HF group showed lower food intake but higher body weight, glucose intolerance and insulin resistance, significant dyslipidemia and increased liver, subcutaneous (inguinal‐ING) and visceral (retroperitoneal‐RP) adipose depots mass, accompanied by adipocyte hypertrophy and decreased cellularity in both adipose tissue depots. FO treatment reversed all these effects, as well as it improved the metabolic activities of isolated adipocytes, such as glucose uptake and lipolysis in both depots, and de novo synthesis of fatty acids in ING adipocytes. HF diet also significantly increased both the pro and anti‐inflammatory cytokines expression by adipocytes, while HF + FO did not differ from control group. Collectively, these data show that the concomitant administration of FO with the HF diet is able to revert metabolic changes triggered by the diet‐induced obesity, as well as to promote beneficial alterations in adipose cell activities. The main mechanism underlying all systemic effects involves direct and differential effects on ING and RP adipocytes.
The manuscript show relevant effects of fish oil (FO) treatment reversing both the metabolic syndrome induced by high‐fat diet (HF) and the changes in subcutaneous (inguinal ‐ING) and visceral (retroperitoneal ‐RP) adipocytes, such as glucose uptake, lipolysis, and lipogenesis. The major findings of our study is that the FO treatment reverses the deleterious effects caused by the excessive intake of a HF diet, and the mechanism involves, at least in part, direct and differential effects on ING and RP adipocytes. Altogether, these effects prevented adipocyte hypertrophy caused by HF diet and reflected in decreased adiposity. Additionally, FO treatment decreased the gene and protein expression of inflammation‐related factors. Thus, the work provided important evidence concerning the effectiveness of a low‐cost agent (as the FO) to treat the metabolic and inflammatory disorders triggered by obesity, which causes thousands of deaths annually and burdens the public coffers.
COVID-19 has affected more than half a billion people worldwide, with more than 6.3 million deaths, but the pathophysiological mechanisms involved in lethal cases and the host determinants that ...determine the different clinical outcomes are still unclear. In this study, we assessed lung autopsies of 47 COVID-19 patients and examined the inflammatory profiles, viral loads, and inflammasome activation. Additionally, we correlated these factors with the patient’s clinical and histopathological conditions. Robust inflammasome activation was detected in the lungs of lethal cases of SARS-CoV-2. Experiments conducted on transgenic mice expressing hACE2 and infected with SARS-CoV-2 showed that Nlrp3 -/- mice were protected from disease development and lethality compared to Nlrp3 +/+ littermate mice, supporting the involvement of this inflammasome in disease exacerbation. An analysis of gene expression allowed for the classification of COVID-19 patients into two different clusters. Cluster 1 died with higher viral loads and exhibited a reduced inflammatory profile than Cluster 2. Illness time, mechanical ventilation time, pulmonary fibrosis, respiratory functions, histopathological status, thrombosis, viral loads, and inflammasome activation significantly differed between the two clusters. Our data demonstrated two distinct profiles in lethal cases of COVID-19, thus indicating that the balance of viral replication and inflammasome-mediated pulmonary inflammation led to different clinical outcomes. We provide important information to understand clinical variations in severe COVID-19, a process that is critical for decisions between immune-mediated or antiviral-mediated therapies for the treatment of critical cases of COVID-19.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Exacerbated expansion of adipose tissue seen in diet-induced obesity leads to endocrine dysfunction and disturbance in adipokine secretion, with such abnormal profile positively associated with type ...2 diabetes and other mild chronic inflammatory conditions.
extract (GbE), a mixture of polyphenols with antioxidant properties, has been recently investigated in a variety of experimental models of endocrine dysfunction, with several potentially beneficial effects identified, including improvement in insulin sensitivity in obese rats, and reduction of weight gain in ovariectomy-induced obesity and diet-induced obesity. The aim of this study was to investigate in high fat diet-induced obese male rats the effects of GbE supplementation for 2 weeks on adipocyte volume and adipose tissue lipid accumulation. GbE supplementation was effective in reducing energy intake in obese rats compared to the saline-treated placebo group. Epididymal adipocyte volume was reduced in GbE-supplemented rats, as were epididymal 1-
C-acetate incorporation into fatty acids, perilipin (
) and fatty acid synthase (
) mRNA, and FAS protein levels. Adipocyte hypertrophy in obesity is associated with insulin resistance, and in the present study we observed a reduction in the adipocyte volume of GbE-supplemented obese rats to dimensions equivalent to adipocytes from non-obese rats. GbE supplementation significantly reduced acetate accumulation and tended to reduce
H-oleate incorporation, into epididymal adipose tissue, suggesting a potentially anti-obesogenic effect in longer term therapies. Further studies that investigate the effects of GbE supplementation in other experimental models are required to fully elucidate its suggested beneficial effects on mild chronic inflammatory conditions.
The rapid increase in the number of individuals with obesity, over the past four decades, is triggered by a number of complex interactions among factors. Despite the plethora of treatments available, ...side effects are commonly observed and, in this context, herbal medicines have been employed as an alternative form of therapy.
extract (GbE) has been described as a promising new pharmacological approach to treat obesity. In order to better comprehend the mechanisms involved with this potential effect, the present study evaluated the effects of GbE treatment on diet-induced obese rats, focusing on the proteome and the oxidative stress defense system of visceral adipose tissue. After 14 days treatment, GbE significantly modulated 25 proteins. Retroperitoneal adipose tissue of treated animals exhibited higher amounts of proteins associated with adipogenesis (decorin), carbon metabolism and mitochondrial function (citrate synthase), and a concomitant reduction in adipocyte hypertrophy. In parallel, GbE down-regulated proteins involved in oxidative stress (peroxiredoxin) and the inflammatory response (complement C3, mast cell protease 1, and Ig gamma-2B chain C region). Moreover, also related to oxidative stress defense, GbE stimulated catalase activity, reduced malondialdehyde levels (lipid peroxidation indicator), and increased lactoylglutathione lyase levels. It was concluded that GbE acts as an antioxidant agent, and improved the proteome profile and oxidative stress response in the adipose tissue of diet-induced obese rats.
Schistosomiasis is a disease caused by Schistosoma. Due to its complex life cycle, evolutionary position and sexual dimorphism, schistosomes have several mechanisms of gene regulation. MicroRNAs ...(miRNAs) are short endogenous RNAs that regulate gene expression at the post-transcriptional level by targeting mRNA transcripts.
Here, we tested 12 miRNAs and identified their putative targets using a computational approach.
We performed the expression profiles of a set of miRNAs and their putative targets during the parasite's life cycle by quantitative reverse transcription-polymerase chain reaction (qRT-PCR).
Our results showed differential expression patterns of the mature miRNAs sma-miR-250; sma-miR-92a; sma-miR-new_4-3p; sma-miR-new_4-5p; sma-miR-new_5-5p; sma-miR-new_12-5p; sma-miR-new_13-3p and sma-miR-new_13-5p. Interestingly, many of the putative target genes are linked to oxidative phosphorylation and are up-regulated in adult-worms, which led us to suggest that miRNAs might play important roles in the post-transcriptional regulation of genes related to energetic metabolism inversion during parasite development. It is noteworthy that the expression of sma-miR-new_13-3p exhibited a negative correlation on SmNADH:ubiquinone oxidoreductase complex I.
Our analysis revealed putative miRNA genes related to important biological processes, such as transforming growth factor beta (TGF-β) signaling, proteasome regulation, glucose and lipid metabolism, immune system evasion and transcriptional regulation.
Gossypium hirsutum
L. represents the best cotton species for fiber production, thus computing the largest cultivated area worldwide.
Meloidogyne incognita
is a root-knot nematode (RKN) and one of the ...most important species of
Meloidogyne
genus, which has a wide host range, including cotton plants. Phytonematode infestations can only be partially controlled by conventional agricultural methods, therefore, more effective strategies to improve cotton resistance to
M. incognita
disease are highly desirable. The present study employed functional genomics to validate the involvement of two previously identified candidate genes, encoding dirigent protein 4—
GhDIR4
and peroxiredoxin-2—
GhPRXIIB
, in cotton defense against
M. incognita
. Transgenic
A. thaliana
plant lines overexpressing
GhDIR4
and
GhPRXIIB
genes were generated and displayed significantly improved resistance against
M. incognita
infection in terms of female nematode abundance in the roots when compared to wild-type control plants. For our best target-gene
GhDIR4
, an in-silico functional analysis, including multiple sequence alignment, phylogenetic relationship, and search for specific protein motifs unveiled potential orthologs in other relevant crop plants, including monocots and dicots. Our findings provide valuable information for further understanding the roles of
GhDIR
and
GhPRXIIB
genes in cotton defense response against RKN nematode.
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