scholarly journals EPA Is Cardioprotective in Male Rats Subjected to Sepsis, but ALA is Not Beneficial

Antioxidants ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 371
Author(s):  
Thibault Leger ◽  
Chrystèle Jouve ◽  
Isabelle Hininger-Favier ◽  
Jean-Paul Rigaudiere ◽  
Frédéric Capel ◽  
...  

It has been proven that dietary eicosapentaenoic acid (C20:5 n-3 or EPA) protects the heart against the deleterious effects of sepsis in female rats. We do not know if this is the case for male rodents. In this case, the efficiency of other n-3 polyunsaturated fatty acids (PUFAs) remains to be determined in both female and male rats. This study aimed at (i) determining whether dietary EPA is cardioprotective in septic male rats; (ii) evaluating the influence of dietary α-linolenic (C18:3 n-3 or ALA) on cardiac function during this pathology; and (iii) finding out the physiological and molecular mechanisms responsible for the observed effects. Sixty male rats were divided into three dietary groups. The animals were fed a diet deficient in n-3 PUFAs (DEF group), a diet enriched with ALA (ALA group) or a diet fortified with EPA (EPA group) for 6 weeks. Thereafter, each group was subdivided into 2 subgroups, one being subjected to cecal ligation and puncture (CLP) and the other undergoing a fictive surgery. Cardiac function was determined in vivo and ex vivo. Several parameters related to the inflammation process and oxidative stress were determined. Finally, the fatty acid compositions of circulating lipids and cardiac phospholipids were evaluated. The results of the ex vivo situation indicated that sepsis triggered cardiac damage in the DEF group. Conversely, the ex vivo data indicated that dietary ALA and EPA were cardioprotective by resolving the inflammation process and decreasing the oxidative stress. However, the measurements of the cardiac function in the in vivo situation modulated these conclusions. Indeed, in the in vivo situation, sepsis deteriorated cardiac mechanical activity in the ALA group. This was suspected to be due to a restricted coronary flow which was related to a lack of cyclooxygenase substrates in membrane phospholipids. Finally, only EPA proved to be beneficial in sepsis. Its action necessitates both resolution of inflammation and increased coronary perfusion. In that sense, dietary ALA, which does not allow the accumulation of vasodilator precursors in membrane lipids, cannot be protective during the pathology.

2010 ◽  
Vol 2010 ◽  
pp. 1-11 ◽  
Author(s):  
Qian Chen ◽  
Elizabeth Eun Jung Kim ◽  
Katrina Elio ◽  
Christopher Zambrano ◽  
Samuel Krass ◽  
...  

Reduced nitric oxide (NO) bioavailability and increased oxidative stress are major factors mediating ischemia/reperfusion (I/R) injury. Tetrahydrobiopterin (BH4) is an essential cofactor of endothelial NO synthase (eNOS) to produce NO, whereas dihydrobiopterin (BH2) can shift the eNOS product profile from NO to superoxide, which is further converted to hydrogen peroxide (H2O2) and cause I/R injury. The effects ofBH4andBH2on oxidative stress and postreperfused cardiac functions were examined in ex vivo myocardial and in vivo femoral I (20 min)/R (45 min) models. In femoral I/R,BH4increased NO and decreasedH2O2releases relative to saline control, and these effects correlated with improved postreperfused cardiac function. By contrast,BH2decreased NO release relative to the saline control, but increasedH2O2release similar to the saline control, and these effects correlated with compromised postreperfused cardiac function. In conclusion, these results suggest that promoting eNOS coupling to produce NO and decreaseH2O2may be a key mechanism to restore postreperfused organ function during early reperfusion.


2011 ◽  
Vol 109 (suppl_1) ◽  
Author(s):  
Rajat Sethi ◽  
Rama Perepu ◽  
Carlos Garcia ◽  
David Dostal

Sex related differences have been noted in cardiovascular disease where females have a lower incidence of heart failure, and a higher rate of heart failure survival. On-the-other-hand, some studies have reported increased mortality in women compared with men. Recent data also suggest that women have an increased risk of death due to O 3 air pollution, which is in contrast to reports that short-term variations in gaseous pollutants are associated with an increase in hospitalization for cardiac disease that is not modified by gender. It has been speculated that because of the nature of the photochemical equilibrium of O 3 in the ambient environment and due to other confounding factors epidemiological investigations of the health effects of O 3 may be using O 3 as an exposure surrogate for other oxidants or co-pollutants, some of which may be interfering with response to O 3 . The present study in a controlled exposure protocol tested the hypothesis that female rats compared to male have decreased sensitivity to cardiac injury subsequent to O 3 exposure. Age matched male/female rats were exposed 8 hrs/day for 28 and 56 days to filtered air or 0.8 ppm O 3 . In order to assess the chronic effects to O 3 , in-vivo cardiac function was assessed, 24 hrs after termination of the O 3 exposure. Compared to female rats, LVDP values significantly decreased in O 3 exposed male rats. This enhanced attenuation of cardiac function in male animals was associated with increased myocardial TNF-alpha (TNF-α) levels and decreased myocardial activities of superoxidase dismutase (SOD). These novel findings suggest that decreased attenuation of cardiac function in O 3 exposed females compared to males exposed to similar conditions was associated with decreased inflammatory mediator production and decreased oxidative stress. Identifying the underlying factors for gender based variations in ozone response is very important to recognize at-risk groups who would benefit from preventive strategies. In addition identification of those at risk, their degree of sensitivity will assist with the cost-benefit analysis of “safe” exposure levels in the public health setting. The long-term goal of this study is in guiding regulatory policies for reduced environmental related health costs.


2018 ◽  
Vol 15 (4) ◽  
pp. 345-354 ◽  
Author(s):  
Barbara D'Orio ◽  
Anna Fracassi ◽  
Maria Paola Cerù ◽  
Sandra Moreno

Background: The molecular mechanisms underlying Alzheimer's disease (AD) are yet to be fully elucidated. The so-called “amyloid cascade hypothesis” has long been the prevailing paradigm for causation of disease, and is today being revisited in relation to other pathogenic pathways, such as oxidative stress, neuroinflammation and energy dysmetabolism. The peroxisome proliferator-activated receptors (PPARs) are expressed in the central nervous system (CNS) and regulate many physiological processes, such as energy metabolism, neurotransmission, redox homeostasis, autophagy and cell cycle. Among the three isotypes (α, β/δ, γ), PPARγ role is the most extensively studied, while information on α and β/δ are still scanty. However, recent in vitro and in vivo evidence point to PPARα as a promising therapeutic target in AD. Conclusion: This review provides an update on this topic, focussing on the effects of natural or synthetic agonists in modulating pathogenetic mechanisms at AD onset and during its progression. Ligandactivated PPARα inihibits amyloidogenic pathway, Tau hyperphosphorylation and neuroinflammation. Concomitantly, the receptor elicits an enzymatic antioxidant response to oxidative stress, ameliorates glucose and lipid dysmetabolism, and stimulates autophagy.


2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Lingyu Yang ◽  
Dehai Xian ◽  
Xia Xiong ◽  
Rui Lai ◽  
Jing Song ◽  
...  

Proanthocyanidins (PCs) are naturally occurring polyphenolic compounds abundant in many vegetables, plant skins (rind/bark), seeds, flowers, fruits, and nuts. Numerousin vitroandin vivostudies have demonstrated myriad effects potentially beneficial to human health, such as antioxidation, anti-inflammation, immunomodulation, DNA repair, and antitumor activity. Accumulation of prooxidants such as reactive oxygen species (ROS) exceeding cellular antioxidant capacity results in oxidative stress (OS), which can damage macromolecules (DNA, lipids, and proteins), organelles (membranes and mitochondria), and whole tissues. OS is implicated in the pathogenesis and exacerbation of many cardiovascular, neurodegenerative, dermatological, and metabolic diseases, both through direct molecular damage and secondary activation of stress-associated signaling pathways. PCs are promising natural agents to safely prevent acute damage and control chronic diseases at relatively low cost. In this review, we summarize the molecules and signaling pathways involved in OS and the corresponding therapeutic mechanisms of PCs.


2020 ◽  
Vol 175 (1) ◽  
pp. 64-74 ◽  
Author(s):  
Nivedita Banerjee ◽  
Hui Wang ◽  
Gangduo Wang ◽  
M Firoze Khan

Abstract Trichloroethene (trichloroethylene, TCE) and one of its reactive metabolites dichloroacetyl chloride (DCAC) are associated with the induction of autoimmunity in MRL+/+ mice. Although oxidative stress plays a major role in TCE-/DCAC-mediated autoimmunity, the underlying molecular mechanisms still need to be delineated. Nuclear factor (erythroid-derived 2)-like2 (Nrf2) is an oxidative stress-responsive transcription factor that binds to antioxidant responsive element (ARE) and provides protection by regulating cytoprotective and antioxidant gene expression. However, the potential of Nrf2 in the regulation of TCE-/DCAC-mediated autoimmunity is not known. This study thus focused on establishing the role of Nrf2 and consequent inflammatory responses in TCE-/DCAC-mediated autoimmunity. To achieve this, we pretreated Kupffer cells (KCs) or T cells with/without tert-butylhydroquinone (tBHQ) followed by treatment with DCAC. In both KCs and T cells, DCAC treatment significantly downregulated Nrf2 and HO-1 expression along with induction of Keap-1 and caspase-3, NF-κB (p65), TNF-α, and iNOS, whereas pretreatment of these cells with tBHQ attenuated these responses. The in vitro findings were further verified in vivo by treating female MRL+/+ mice with TCE along with/without sulforaphane. TCE exposure in mice also led to reduction in Nrf2 and HO-1 but increased phospho-NF-κB (p-p65) and iNOS along with increased anti-dsDNA antibodies. Interestingly, sulforaphane treatment led to amelioration of TCE-mediated effects, resulting in Nrf2 activation and reduction in inflammatory and autoimmune responses. Our results show that TCE/DCAC mediates an impairment in Nrf2 regulation. Attenuation of TCE-mediated autoimmunity via activation of Nrf2 supports that antioxidants sulforaphane/tBHQ could be potential therapeutic agents for autoimmune diseases.


1985 ◽  
Vol 249 (3) ◽  
pp. E276-E280 ◽  
Author(s):  
W. S. Evans ◽  
R. J. Krieg ◽  
E. R. Limber ◽  
D. L. Kaiser ◽  
M. O. Thorner

The effects of gender and the gonadal hormone environment on basal and stimulated growth hormone (GH) release by dispersed and continuously perifused rat anterior pituitary cells were examined. Cells from intact male and diestrus day 2 female rats and from castrate male rats either untreated or treated with testosterone (T) or 17 beta-estradiol (E2) were used. Basal GH release (ng/min per 10(7) cells; mean +/- SE) by cells from diestrus day 2 female rats was less than by cells from castrate rats treated with T (4.3 +/- 0.6 vs. 11.4 +/- 2.7, respectively; P less than 0.025). No other differences in basal release were detected. Concentration-response relationships were documented between human GH-releasing factor 40 (hGRF-40; 0.03-100 nM given as 2.5-min pulses every 27.5 min) and GH release. Mean (+/- SE) overall GH release (ng/min per 10(7) cells) above base line was greater by cells from intact male rats (496 +/- 92) than by cells from castrate (203 +/- 37.3; P less than 0.0001), castrate and T-treated (348 +/- 52.8; P = 0.008), or castrate and E2-treated (58.1 +/- 6.8; P less than 0.001) male rats or by diestrus day 2 rats (68.6 +/- 9.5; P = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)


2003 ◽  
Vol 285 (2) ◽  
pp. H499-H506 ◽  
Author(s):  
Stéphanie Héon ◽  
Martin Bernier ◽  
Nicolas Servant ◽  
Stevan Dostanic ◽  
Chunlei Wang ◽  
...  

Doxorubicin (DOX), an anticancer drug, causes a dose-dependent cardiotoxicity. Some evidence suggests that female children have an increased risk for DOX-mediated cardiac damage. To determine whether the iron chelator dexrazoxane (DXR) could reduce DOX-induced cardiotoxicity in the young, we injected day 10 neonate female and male rat pups with a single dose of saline or DOX, DXR, or DXR + DOX (20:1). We followed body weight gain with growth, measured cardiac hypertrophy after a 2-wk swim exercise program, markers of apoptosis (Bcl-2, BAX, BNIP1, caspase 3 activation), oxidative stress (heme oxygenase 1, protein carbonyl levels), the chaperone protein clusterin, and the transcriptional activator early growth response gene-1 (Egr-1) in hearts of nonexercised and exercised rats on neonate day 38. All DOX-alone and DXR + DOX-treated rats showed decreased weight gain, with female rats affected earlier than male rats. DXR-alone, DOX-alone, and DXR + DOX-treated rats had an increased heart weight-to-body weight (heart wt/body wt) ratio after the exercise program with female rats showing the largest increase in heart wt/body wt. Drug-treated females also showed increased cardiac apoptosis, as measured by the increased expression of the proapoptotic proteins BAX and BNIP1 and the appearance of caspase 3 activation products, and oxidative stress, as measured by increased heme oxygenase 1 expression, and reduced Egr-1 and clusterin expression when compared with the similarly treated male rats. We conclude that DXR preinjection did not reduce DOX-induced noncardiac and cardiac damage and that young female rats were more susceptible to DXR and DOX toxicities than age-matched male rats.


2002 ◽  
Vol 22 (2) ◽  
pp. 183-195 ◽  
Author(s):  
Aigang Lu ◽  
Rui-qiong Ran ◽  
Joseph Clark ◽  
Melinda Reilly ◽  
Alex Nee ◽  
...  

Estradiol reduces brain injury from many diseases, including stroke and trauma. To investigate the molecular mechanisms of this protection, the effects of 17-β-estradiol on heat shock protein (HSP) expression were studied in normal male and female rats and in male gerbils after global ischemia. 17-β-Estradiol was given intraperitoneally (46 or 460 ng/kg, or 4.6 μg/kg) and Western blots performed for HSPs. 17-β-Estradiol increased hemeoxygenase-1, HSP25/27, and HSP70 in the brain of male and female rats. Six hours after the administration of 17-β-estradiol, hemeoxygenase-1 increased 3.9-fold (460 ng/kg) and 5.4-fold (4.6 μg/kg), HSP25/27 increased 2.1-fold (4.6 μg/kg), and Hsp70 increased 2.3-fold (460 ng/kg). Immunocytochemistry showed that hemeoxygenase-1, HSP25/27,and HSP70 induction was localized to cerebral arteries in male rats, possibly in vascular smooth muscle cells. 17-β-Estradiol was injected intraperitoneally 20 minutes before transient occlusion of both carotids in adult gerbils. Six hours after global cerebral ischemia, 17-β-estradiol (460 ng/kg) increased levels of hemeoxygenase-1 protein 2.4-fold compared with ischemia alone, and HSP25/27 levels increased 1.8-fold compared with ischemia alone. Hemeoxygenase-1 was induced in striatal oligodendrocytes and hippocampal neurons, and HSP25/27 levels increased in striatal astrocytes and hippocampal neurons. Finally, Western blot analysis confirmed that estrogen induced heat shock factor-1, providing a possible mechanism by which estrogen induces HSPs in brain and other tissues. The induction of HSPs may be an important mechanism for estrogen protection against cerebral ischemia and other types of injury.


Marine Drugs ◽  
2018 ◽  
Vol 16 (11) ◽  
pp. 431 ◽  
Author(s):  
Rosa Vitale ◽  
Enrico D'Aniello ◽  
Stefania Gorbi ◽  
Andrea Martella ◽  
Cristoforo Silvestri ◽  
...  

Although the chemical warfare between invasive and native species has become a central problem in invasion biology, the molecular mechanisms by which bioactive metabolites from invasive pests influence local communities remain poorly characterized. This study demonstrates that the alkaloid caulerpin (CAU)—a bioactive component of the green alga Caulerpa cylindracea that has invaded the entire Mediterranean basin—is an agonist of peroxisome proliferator-activated receptors (PPARs). Our interdisciplinary study started with the in silico prediction of the ligand-protein interaction, which was then validated by in vivo, ex vivo and in vitro assays. On the basis of these results, we candidate CAU as a causal factor of the metabolic and behavioural disorders observed in Diplodus sargus, a native edible fish of high ecological and commercial relevance, feeding on C. cylindracea. Moreover, given the considerable interest in PPAR activators for the treatment of relevant human diseases, our findings are also discussed in terms of a possible nutraceutical/pharmacological valorisation of the invasive algal biomasses, supporting an innovative strategy for conserving biodiversity as an alternative to unrealistic campaigns for the eradication of invasive pests.


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