Treatment of oxidative stress in brain of ovariectomized rats with omega-3 and lipoic acid

Fish oil supplementation protects against protein undernutrition-induced testicular and ovarian biochemical alterations in rats

Proteins are required for biological functions and their inadequacy might impair the growth and development of the reproductive system. The study investigated the effects of fish oil (FO) supplementation on low-protein diet-induced alterations in male and female reproductive organs. Male and female rats were assigned randomly to four groups respectively. The NPD rats had five rats per group and were given 16% casein diet while the LPD rats had eight rats per group and received 5% casein diet. After the 8th week, FO was administered for 3 weeks via oral gavage at a concentration of 400mg Kg^-1 after which the rats were sacrificed and testes and ovaries were excised. LPD-fed rats showed lower body weights for both genders. In LPD-fed rats, NO was significantly increased while GSH, vitamins C and E levels, the activities of CAT (except in ovaries), and GST were significantly reduced in both tissues. The activities of SOD and GPx were only reduced in the testes including sperm count, motility, and increase deformed sperm cells. Testosterone and progesterone levels were also reduced and lipid homeostasis was disrupted in the plasma of LPD-fed rats. FO supplementation reduces the NO, CHOL, TG, LDL (in females), and VLDL but significantly improves HDL (in females), testosterone, and progesterone levels, sperm count, motility, and morphology. The antioxidant status of both tissues also increased significantly in LPD-fed rats. Conclusively, FO might be effective in improving testicular and ovarian functions and for the maintenance of plasma lipid homeostasis in LPD-fed rats.

Behavioral, Oxidative, and Biochemical Effects of Omega-3 on an Ovariectomized Rat Model of Menopause

OBJECTIVES

Menopause induces changes in neuronal transmission, leading to anxiety and depression. Changes in the brain's glutamate levels cause psychological behavior in postmenopausal women. Omega-3 has been studied to improve some of these behaviors.

METHODS

Twenty-four female Wistar rats were divided into four groups: sham-operated treated with water (SO-W), sham-operated treated with omega-3 (SO-O), ovariectomized (OVX) treated with water (OVX-W), and bilateral OVX treated with omega-3 (OVX-O). These treatments were performed for 20 days via gavage, before and after surgery, totaling 40 days.

RESULTS

In the forced swimming, elevated plus-maze, and open field tests to assess behaviors, such as depression and anxiety, omega-3 improved these behaviors in both treated groups. The levels of thiobarbituric acid reactive substances (TBARS) in the brain were not different between the groups; however, there was a significant decrease in the catalase activity in the SO-O group compared with the SO-W group (P < 0.05). The glutamate level in the cerebrospinal fluid (CSF) was elevated in the SO-O group (P < 0.001) but not in the OVX-W or OVX-O groups.

CONCLUSIONS

These results bring novel data when related to the glutamatergic system in the SO-O group. This has suggested that the action mechanism of omega-3 was not dependent on glutamate levels in the CSF of the OVX group, but it played a regulatory role in the sham-operated animals. To confirm this, more studies are needed to explore this field when relating to the estrogen and glutamate receptor changes in specific brain regions.

DHA-rich fish oil and Tualang honey reduce chronic stress-induced oxidative damage in the brain of rat model

Background

Exposure to chronic stress induces oxidative damage which alters the dynamic balance between antioxidant and pro-oxidant activities in the brain. Tualang honey (TH) is a Malaysian wild multifloral honey which has been shown to contain high amount antioxidants. DHA-rich fish oil is a form of omega-3 fatty acids found in fish which also possesses some antioxidant activity. This study aimed to evaluate anti-stress activity of DHA-rich fish oil, TH and their combination on several parameters of oxidative stress in chronic stress rat model.

Methods

Fifty male Sprague Dawley rats were divided into (i) control, (ii) stress-exposed, (iii) stress-exposed and treated with TH (1 g/kg body weight twice daily), (iv) stress-exposed and treated with DHA-rich fish oil (450 mg/kg body weight twice daily), and (v) stress-exposed and treated with a combination of TH and DHA-rich fish oil. The chronic stress regimen consisted of a combination of restraint stress and a swim stress test for 28 days.

Results

DHA-rich fish oil and TH significantly (p < 0.05) supressed stress-induced elevation of serum corticosterone and lipid peroxidation, and caused a significant increase in total antioxidant capacity. For glutathione status, only TH significantly reduced stress-induced elevation of oxidised glutathione (GSSG) and normalised GSH/GSSG ratio. Conclusion: Both DHA-rich fish oil and TH have protective effects against brain oxidative stress but consuming these substances together does not seem to provide an additional benefit compared to consuming them separately.

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Investigated the effect of honey, DHA and their combination in single experimental setting.

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Tualang honey and DHA-rich fish oil can attenuate brain oxidative stress in chronic stress rat model.

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Combination of Tualang honey and DHA -rich fish oil is not superior than consuming these substances separately.

Protective effect of metformin against ovariectomy induced depressive- and anxiety-like behaviours in rats: role of oxidative stress

Several studies have shown that low estrogen levels can lead to an increase in the incidence of depression and anxiety during menopause. The hippocampus and prefrontal cortex are parts of the brain involved in depressive- and anxiety-like behaviors. Recent studies have revealed that metformin has neuroprotective effects mainly due to its antioxidant properties. The aim of the present study was to examine the therapeutic potential of metformin in depressive- and anxiety-like behavior as well as oxidative stress in the prefrontal cortex and hippocampus of ovariectomized rats. Young female Wistar Albino rats were distributed into four groups (n:8): control, metformin-administered control, ovariectomized and metformin administered ovariectomized groups. Metformin (25 mg/kg) was administered daily by oral gavage for 2 weeks. Forced swimming test and open field test were performed to evaluate depression- and anxiety-like behaviors, respectively. Following the treatment with metformin, the tissues of the hippocampus and prefrontal cortex were isolated for the measurement of malondialdehyde, reduced glutathione and ascorbic acid contents. Ovariectomy resulted in depressive- and anxiety-like behaviors, and besides, increased content of malondialdehyde in both prefrontal cortex and hippocampus. The levels of ascorbic acid and glutathione were found to be reduced in ovariectomized rats. Metformin treatment significantly decreased depressive behaviour and malondialdehyde content in the prefrontal cortex. Reducing oxidative stress of the prefrontal cortex was suggested as a possible mechanism implicated in the beneficial effects of metformin on ovariectomy-induced depressive-like behaviour. We believe that the therapeutic efficiency of metformin needs to be tested for potential clinical use in surgical menopause or gonadal hormone deficiency women with depression.

Energy metabolism and sources of oxidative stress in wooden breast - a review

Modern broilers show dramatic growth over a short interval and contribute directly to the success of the poultry meat industry. The growth performance of commercial broilers is a result of genetic selection for "performance traits", such as body size, meat yield, and feed conversion rate. However, due to the rapid growth rate of modern commercial broilers, several growth-related conditions have arisen, increasing economic losses and consumer concerns. Among the most economically consequential is the muscle disorder called wooden breast. Together with associated myopathies such as white striping and spaghetti meat, wooden breast is causing losses of $200 million a year in the U.S. alone and occurs worldwide. No causative factors are known for wooden breast to date. Wooden breast can affect over 80% of broilers in a flock, yet no methods of amelioration are currently available. Overall, the evidence suggests that wooden breast is a genetic, age-dependent condition associated with fast growth rate. The primary features of wooden breast are muscle degeneration and fibrosis, high levels of oxidative stress, hypoxia, and altered energy metabolism. Recent work has also implicated reduced pectoral vessel density in the pathogenesis of wooden breast. This review examines the history of myopathies in commercial broilers and the relationship of myopathies to metabolism and oxidative performance. This review summarizes the foundational knowledge of wooden breast and provides a platform for further investigation of wooden breast.

Effects of lipoic acid and ω-3 long-chain polyunsaturated fatty acids on the kidney in the ovariectomized rat model of menopause

OBJECTIVES

The loss of antioxidant protection from estrogen during menopause may lead to oxidative stress in the kidneys. Thus, antioxidant supplementation may potentially decrease the menopause-derived oxidative stress. The aim of this study was to evaluate the effect of α-lipoic acid (LA) and ω-3 long-chain polyunsaturated fatty acids on the redox profile of the kidneys in the ovariectomized rat model of menopause.

METHODS

We assessed oxidative damage markers and antioxidant defenses in the kidneys of ovariectomized rats supplemented with LA, docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA). Animals received 3 mo of dietary supplementation.

RESULTS

Ovariectomy did not increase the levels of the damage markers carbonyl and malondialdehyde. EPA supplementation increased carbonyl and malondialdehyde levels. Ovariectomy increased fumarase activity but did not affect the levels of vitamin C, glutathione, and glutathione S-transferase activity. LA, DHA, and EPA supplementation decreased fumarase activity, but increased the levels of vitamin C, glutathione, and glutathione S-transferase activity. Vitamin E, superoxide dismutase, glutathione peroxidase, and peroxide consumption were not affected by ovariectomy or supplementation.

CONCLUSIONS

The results suggest that ovariectomy did not affect the redox profile in the kidneys. LA, DHA, and EPA supplementation increased certain endogenous antioxidants; however, EPA may have a prooxidant effect on the kidneys.

The effect of n-3 long-chain polyunsaturated fatty acids and lipoic acid on the heart in the ovariectomized rat model of menopause

Menopause occurs as consequence of ovarian senescence that leads to a drop of oestrogen hormone. The decreased oestrogen levels combined with the impairment of the redox system may contribute to the increased risk of postmenopausal cardiovascular disease. Supplementation with antioxidants may be an alternative to reduce cardiovascular risk. The study evaluated the effect of dietary supplementation with docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and α-lipoic acid (LA) for a period of 16 weeks on oxidative stress biomarkers in the hearts of ovariectomized 3-month-old rats. Ovariectomy did not increase the level of the damage markers malondialdehyde and carbonyl, and both were decreased by LA supplementation. Ovariectomy increased the levels of the endogenous antioxidants glutathione, vitamin C and H₂O₂ consumption, after restoration by DHA, EPA, and LA supplementation. Vitamin E, glutathione peroxidase, glutathione-S-transferase, and superoxide dismutase are not altered by ovariectomy. Lipid and protein damage are not increased after ovariectomy and a portion of the endogenous antioxidants concomitantly increased, suggesting that hearts may be protected by these antioxidants. DHA, EPA, and LA restored these endogenous antioxidants, showing that all evaluated supplements are effective in modulating the antioxidant redox system in the heart. LA showed additional effect on redox markers, decreasing lipid and protein damage markers.

Vaginal lipidomics of women with vulvovaginal candidiasis and cytolytic vaginosis: A non-targeted LC-MS pilot study

Objective

To characterize the lipid profile in vaginal discharge of women with vulvovaginal candidiasis, cytolytic vaginosis, or no vaginal infection or dysbiosis.

Design

Cross-sectional study.

Setting

Genital Infections Ambulatory, Department of Tocogynecology, University of Campinas, Campinas, São Paulo–Brazil.

Sample

Twenty-four women were included in this study: eight with vulvovaginal candidiasis, eight with cytolytic vaginosis and eight with no vaginal infections or dysbiosis (control group).

Methods

The lipid profile in vaginal discharge of the different study groups was determined by liquid chromatography-mass spectrometry and further analyzed with MetaboAnalyst 3.0 platform.

Main outcome measures

Vaginal lipids concentration and its correlation with vulvovaginal candidiasis and cytolytic vaginosis.

Results

PCA, PLS-DA and hierarchical clustering analyses indicated 38 potential lipid biomarkers for the different groups, correlating with oxidative stress, inflammation, apoptosis and integrity of the vaginal epithelial tissue. Among these, greater concentrations were found for Glycochenodeoxycholic acid-7-sulfate, O-adipoylcarnitine, 1-eicosyl-2-heptadecanoyl-glycero-3-phosphoserine, undecanoic acid, formyl dodecanoate and lipoic acid in the vulvovaginal candidiasis group; N–(tetradecanoyl)-sphinganine, DL-PPMP, 1-oleoyl-cyclic phosphatidic, palmitic acid and 5-aminopentanoic acid in the cytolytic vaginosis group; and 1-nonadecanoyl-glycero-3-phosphate, eicosadienoic acid, 1-stearoyl-cyclic-phosphatidic acid, 1-(9Z,12Z-heptadecadienoyl)-glycero-3-phosphate, formyl 9Z-tetradecenoate and 7Z,10Z-hexadecadienoic acid in the control group.

Conclusions

Lipids related to oxidative stress and apoptosis were found in higher concentrations in women with vulvovaginal candidiasis and cytolytic vaginosis, while lipids related to epithelial tissue integrity were more pronounced in the control group. Furthermore, in women with cytolytic vaginosis, we observed higher concentrations of lipids related to bacterial overgrowth.

Effects of lipoic acid and n-3 long-chain polyunsaturated fatty acid on the liver ovariectomized rat model of menopause

BACKGROUND

Bilateral ovariectomy is an experimental model used to analyse the effects of menopause and develop strategies to mitigate the deleterious effects of this condition. Supplementation of the diet with antioxidants has been used to reduce potential oxidative stress caused by menopause. The purpose of the study was to analyse the effects of α-lipoic acid (LA), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), dietary supplementation on oxidative stress in the livers of ovariectomized rats.

METHODS

In this study, we evaluated the effect of dietary supplementation with LA, DHA and EPA for a period of 16 weeks on oestrogen levels and oxidative stress biomarkers in the livers of ovariectomized 25 three-month-old rats.

RESULTS

Serum oestrogen levels were lower after ovariectomy but were not altered by dietary treatments. LA was capable of acting in the liver, recovering the activity of the antioxidant enzymes superoxide dismutase and glutathione peroxidase, and reducing protein oxidative damage. Moreover, LA supplementation reduced nitrite and nitrate levels. DHA and EPA recovered the antioxidant activity of cytosolic and mitochondrial superoxide dismutase, decreasing protein oxidation. Protection against lipid oxidation differed between treatments. The DHA-treated group showed increased levels of the lipid peroxidation biomarker malondialdehyde compared to the ovariectomized group. However, malondialdehyde levels were not altered by EPA treatment.

CONCLUSIONS

The results suggest that the antioxidant response varies among evaluated supplementations and all supplements were able to alter enzymatic and non-enzymatic antioxidants in the livers of ovariectomized rats. DHA presented the most evident antioxidant effect, decreasing protein and lipid damage.