Sitosterol prevents obesity-related chronic inflammation

The physiological roles of phytosterols in chronic inflammation, which are believed to be involved in the underlying mechanisms for metabolic diseases, have yet to be elucidated. Therefore, in the present study, we aimed to elucidate the physiological roles of phytosterols in both clinical studies and animal experiments. We observed the existence of rather specific negative correlations between the serum sitosterol level and the serum IL-6 and the TNF-α levels in both diabetic subjects (n = 46) and non-diabetic subjects (n = 178). Multiple regression analyses also revealed that the serum IL-6 and TNF-α levels exhibited strong negative correlations with the serum sitosterol levels. When ABCG5/8 KO mice with markedly elevated plasma sitosterol levels and ABCG5/8 hetero mice were fed a high-fat diet, we observed that the increase in body weight, the fatty liver changes, and the expansion of perigonadal adipose tissues were suppressed in ABCG5/8 KO mice without any modulation of food intake. We also observed that the plasma IL-6 and TNF-α levels, the expressions of TNF-α and PAI-1 in the liver and the expressions of the IL-6, TNF-α, and MCP-1 levels in the adipose tissue were lower in ABCG5/8 KO mice. These results suggest that sitosterol might suppress obesity-related chronic inflammation and might be applicable to the treatment of metabolic diseases.     

Study of the therapeutic effects of Lactobacillus and α-lipoic acid against dimethylnitrosamine-induced liver fibrosis in rats

Lactobacillus (LB) and α-lipoic acid (ALA) were investigated to compare their protective effects against dimethylnitrosamine (DMN)-induced liver fibrosis in rats. Animals were either injected intraperitoneally with DMN to induce hepatic fibrosis, or were left untreated (negative control). For the DMN + LB and DMN + ALA treatment groups, at two weeks of DMN treatment LB or ALA was added to the feed and supplementation continued until the experimental endpoint at sixty days. At the study endpoint, expression of IL-1β, IL-6, IL-10, TNF-α, IFN-γ, TGF-β1, COL1-α1 genes and the concentration of glutathione and malondialdehyde were measured in liver tissues, while GOT, GPT, and ALP concentrations were measured in blood. Body weights remained higher in NC and DMN + LB groups compared to DMN and DMN + ALA groups, while activity of GOT and GPT in serum was lower in DMN + LB and DMN + ALA groups compared to the DMN group. Compared to other treatment groups, in the DMN group expression of both TGF-β1 and, COL1-α1 mRNAs and pro-inflammatory cytokines increased, while that of 1L-10 decreased. Furthermore, LB and ALA treatments increased antioxidant activity of glutathione and decreased malondialdehyde in comparison to the DMN group. Between LB and ALA treatments, glutathione concentration was higher in the DMN + LB group, while malondialdehyde was lower. Our results indicate that both LB and ALA exert hepatoprotective effects against DMN-induced liver fibrosis. Their beneficial effects may be partly associated with down-regulation of both TGF-β1 and COL1-α1 signaling, which may be accounted for reduction of increased oxidative stress and TNF-α production.     

Interleukin-10 modulates pro-apoptotic effects of TNF-α in human articular chondrocytes in vitro

The aim of this study is to determine if there is an antagonistic effect between tumour necrosis factor (TNF)-α and the immunoregulatory interleukin (IL)-10 on chondrocytes survival. Serum-starved primary human articular chondrocytes were stimulated with either 10 ng/ml recombinant TNF-α, IL-10 or a combination of both (at 10 ng/ml each). Chondrocyte apoptosis was determined by measuring caspase-3/7, -8 and -9 activities using caspase assays. Mitochondrial apoptotic inducer bax, and the suppressor bcl-2 were evaluated using western blotting at 48 h. Results indicated that TNF-α increased caspase activities and resulted in a significant (p = 0.001) increase in bax/bcl-2 ratio. Stimulation with IL-10 did not alter caspase activities, while co-treatment with IL-10 and TNF-α inhibited TNF-α induced caspase activities and significantly (p > 0.004) impaired bax/bcl-2 ratio. At 24 h, mRNA levels for collagen type II, TNF-α and IL-10 were determined using real-time RT-PCR. Stimulation with TNF-α or TNF-α and IL-10 significantly inhibited collagen type II and increased IL-10 and TNF-α mRNA expression. IL-10 modulated the pro-apoptotic capacity of TNF-α in chondrocytes as shown by the decrease in caspase activities and bax/bcl-2 ratio compared to TNF-α stimulated chondrocytes, suggesting a mostly antagonistic interplay of IL-10 and TNF-α on mitochondrial apoptotic pathways.     

Th1/Th2 cytokine profile in childhood-onset systemic lupus erythematosus

ObjectiveTo determine the serum levels of Th1 (IL-12, IFN-γ,TNF-α) and Th2 (IL-5, IL-6 and IL-10) cytokines in childhood-onset SLE, first-degree relatives and healthy controls. To elucidate their association with disease activity, laboratory and treatment features.MethodsWe included 60 consecutive childhood-onset SLE patients [median age 18 years (range 10–37)], 64 first-degree relatives [median 40 (range 28–52)] and 57 healthy [median age 19 years (range 6–30 years)] controls. Controls were age and sex-matched to SLE patients. SLE patients were assessed for clinical and laboratory SLE manifestations, disease activity (SLEDAI), damage (SDI) and current drug exposures. Mood and anxiety disorders were determined through Becks Depression (BDI) and Anxiety Inventory (BAI). Th1 (IL-12, IFN-γ,TNF-α) and Th2 (IL-5, IL-6 and IL-10) cytokines levels were measured by ELISA and compared by non-parametric tests.ResultsSerum TNF-α (p = 0.004), IL-6 (p = 0.007) and IL-10 (p = 0.03) levels were increased in childhood-onset SLE patients when compared to first-degree relatives and healthy controls. TNF-α levels were significantly increased in patients with active disease (p = 0.014) and correlated directly with SLEDAI scores (r = 0.39; p = 0.002). IL-12 (p = 0.042) and TNF-α (p = 0.009) levels were significantly increased in patients with nephritis and TNF-α in patients with depression (p = 0.001). No association between cytokine levels and SDI scores or medication was observed.ConclusionTh1 cytokines may play a role in the pathogenesis of neuropsychiatric and renal manifestations in childhood-onset SLE. The correlation with SLEDAI suggests that TNF-α may be a useful biomarker for disease activity in childhood-onset SLE, however longitudinal studies are necessary to determine if increase of this cytokine may predict flares in childhood-onset SLE.     

Elevation in liver enzymes is associated with increased IL-2 and predicts severe outcomes in clinically apparent dengue virus infection

The objective of the present study was to assess the circulating TNF-α and IL-2 levels in dengue virus (DENV) infected patients and to correlate these with clinical severity of DENV infections. A single analyte quantitative immunoassay was used to detect TNF-α and IL-2 in 24 dengue fever (DF) and 43 dengue haemorrhagic fever (DHF) patients, 15 healthy adults and 6 typhoid patients. The mean TNF-α and IL-2 levels of DENV- infected patients were higher than that of healthy adults and typhoid patients. No significant difference in TNF-α levels was noted between DF and DHF patients (p = 0.5) but a significant increase in IL-2 levels was observed in DHF compared with DF patients (mean of DF = 59.7 pg/mL, mean of DHF = 166.9 pg/mL; p = 0.02). No significant association of TNF-α or IL-2 levels was noted with packed cell volume (>45), thrombocytopenia, leucopenia or the presence of viraemia. The liver function tests measuring AST (aspartate aminotransferase) (p = 0.01) and ALT (alanine aminotransferase) (p = 0.02) levels were significantly elevated in DENV-infected patients. AST:ALT was significantly elevated in DHF/DSS (dengue shock syndrome) compared with DF patients. A significant positive linear correlation was noted between AST and IL-2 (r = 0.31; p = 0.01) and ALT and IL-2 elevations (r = 0.2; p = 0.02). Thus, AST and ALT levels correlate with both disease severity and circulating IL-2 levels. We suggest a role for circulating IL-2 in liver dysfunction and propose that a combined assessment of AST/ALT in conjunction with IL-2 at the early stages of symptomatic DENV infection may be useful to predict the severe forms of dengue.     

Antithrombin III,but not C1 esterase inhibitor reduces inflammatory response in lipopolysaccharide-stimulated human monocytes in an ex-vivo whole blood setting

In order to examine the immunomodulatory effects of antithrombin III (AT-III) and C1 esterase inhibitor (C1-INH) in human monocytes, we investigated the intracellular expression of interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)-α in an ex-vivo laboratory study in a whole blood setting.Heparinized whole blood samples from 23 healthy male and female volunteers (mean age: 27 ± 7 years) were pre-incubated with clinically relevant concentrations of AT-III (n = 11) and C1-INH (n = 12), then stimulated with 0.2 ng/mL lipopolysaccharide (LPS) for 3 h. After phenotyping CD14⁺ monocytes, intracellular expression of IL-6, IL-8, and TNF-α was assessed using flow cytometry. In addition, 12 whole blood samples (AT-III and C1-INH, n = 6 each) were examined using hirudin for anticoagulation; all samples were processed in the same way. To exclude cytotoxicity effects, 7-amino-actinomycin D and Nonidet P40 staining were used to investigate probes.This study is the first to demonstrate the influence of C1-INH and AT-III on the monocytic inflammatory response in a whole blood setting, which mimics the optimal physiological setting. Cells treated with AT-III exhibited significant downregulation of the proportion of gated CD14⁺ monocytes for IL-6 and IL-8, in a dose-dependent manner; downregulation for TNF-α did not reach statistical significance. There were no significant effects on mean fluorescence intensity (MFI). In contrast, C1-INH did not significantly reduce the proportion of gated CD14⁺ monocytes or the MFI regarding IL-6, TNF-α, and IL-8. When using hirudin for anticoagulation, no difference in the anti-inflammatory properties of AT-III and C1-INH in monocytes occurs.Taken together, in contrast to TNF-α, IL-6 and IL-8 were significantly downregulated in monocytes in an ex-vivo setting of human whole blood when treated with AT-III. This finding implicates monocytes as an important point of action regarding the anti-inflammatory properties of AT-III in sepsis. C1-INH was unable to attenuate the monocytic response, which supports the hypothesis that other cellular components in whole blood (e.g., neutrophils) might be responsible for the known effects of C1-INH in inflammation.     

Berberine improves the intestinal antioxidant status of laboratory mice,Mus musculus

Oral administration of berberine chloride to mice induced an obvious enhancement in jejunal health status as expressed by the significant reduction of apoptotic cells within the intestinal villi from 15.5 to 8.3 apoptotic cell/10 VCU. In addition, jejunal antioxidant biomarkers were significantly improved as revealed by the increase in the activities of catalase and glutathione peroxidase enzymes with a concurrent increase in reduced glutathione levels and total antioxidant capacity. Also, it was associated with a significant decrease in oxidative damage biomarkers of hydrogen peroxides, malondialdehyde, nitrite/nitrate, inducible nitric oxide synthase and protein carbonyl content. Moreover, BBR treatment induced a reduction in the pro-inflammatory cytokine, TNF-α by about 40%. It is highly recommended to use berberine as food supplements or as natural drug therapy to enhance the antioxidant status within the intestinal tissue.     

Tumor Necrosis Factor-α, Interleukins-12(p40), 6, and 10 levels in cerebrospinal fluid and outcome prediction in Ossimi sheep with encephalitic listeriosis

Encephalitic listeriosis in sheep is a life-threatening disease. However, little is known about the cytokine response and their predictive value in this disease. The aim of present study was to assess the prognostic significance of Tumor Necrosis Factor-α (TNF-α), Interleukin-12(p40) (IL-12 p40), Interleukin-6 (IL-6), and Interleukin 10 (IL-10) levels in cerebrospinal fluid (CSF) in sheep with encephalitic listeriosis. Fifty-nine ewes in 14 flocks were diagnosed clinically as having listeriosis. CSF was collected and subjected to bacteriological examination and estimation of selected cytokines. Twenty-eight ewes were confirmed to be infected with Listeria monocytogenes. Based on antimicrobial sensitivity test, sheep were treated and the outcome was recorded as survivors (n = 10) and non-survivors (n = 18). Cutoff points for CSF cytokines were determined by Receiver operating characteristic analysis (ROC). Association between levels of CSF cytokines and outcome of listeriosis was assessed by logistic regression. TNF-α, IL-6 and IL-12(p40) levels as well as TNF-α/IL-10 ratio were significantly higher in non-survivors than survivors (p = 0.002, 0.0021, 0.0033, and 0.001, respectively). However, IL-10 level was significantly lower in non-survivors than survivors (p = 0.0058). ROC analysis revealed that IL-6 and TNF-α/IL-10 ratio had the highest AUC values (0.98, 0.984, respectively). Final multivariate logistic regression model showed that TNF-α/IL-10 ratio was the only variable that has predictive value for mortality in diseased sheep (p: 0.001; OR: 7.2; 95% CI: 5.7–9.8). TNF-α showed a positive correlation with IL-12β (r = 0.917) and IL-6 (r = 0.965). IL-12 (p40) showed also a positive correlation with IL-6 (r = 0.906). However, IL-10 showed a negative correlation with TNF-α (r = −0.915), IL-12(p40) (r = −0.790), and IL-6 (r = −0.902). In conclusion, TNF-α/IL-10 ratio may provide predictive information about outcome of encephalitic listeriosis in sheep.     

Lack of association of IL-6 (−174 G > C) and TNF-α (−238 G > A) variants with paranoid schizophrenia in Indian Bengalee population

Schizophrenia is a chronic debilitating neuropsychiatric disorder with complex etiopathology. Growing evidence suggests a significant role of chronic low grade inflammation in the pathophysiology of schizophrenia. Multiple immunological, genetic polymorphism and gene expression studies have established crucial roles of certain pro-inflammatory cytokines in the immune-mediated risk of schizophrenia. Although genetic studies suggest some variants within the pro-inflammatory IL-1β, IL-6, and TNF-α genes conferring risk to schizophrenia, the results however have been contradictory in various populations. In the present investigation, promoter SNPs of IL-6 (?174 G > C) and TNF-α (?238 G > A) genes have been studied to evaluate whether these variants contribute to schizophrenia susceptibility in Indian Bengalee population. Genotyping of the above SNPs was done in 100 well characterized and confirmed cases of paranoid schizophrenia and equal number of healthy donors belonging to the same ethnic group by using ABI 3730 Genetic Analyzer. No significant differences in genotype as well as allele frequencies were observed for IL-6 and TNF-α variants between the patient and control groups.     

Changes in glutathione-dependent redox status and mitochondrial energetic strategies are part of the adaptive response during the filamentation process in Candida albicans

Candida albicans is an opportunist pathogen responsible for a large spectrum of infections, from superficial mycosis to systemic diseases called candidiasis. Its ability to grow in various morphological forms, such as unicellular budding yeast, filamentous pseudohyphae and hyphae, contributes to its survival in the diverse microenvironments it encounters in the host. During infection in vivo, C. albicans is faced with high levels of reactive oxygen species (ROS) generated by phagocytes, and the thiol-dependent redox status of the cells reflects their levels of oxidative stress. We investigated the role of glutathione during the transition between the yeast and hyphal forms of the pathogen, in relation to possible changes in mitochondrial bioenergetic pathways. Using various growth media and selective mutations affecting the filamentation process, we showed that C. albicans filamentation was always associated with a depletion of intracellular glutathione levels. Moreover, the induction of hypha formation resulted in general changes in thiol metabolism, including the oxidation of cell surface − SH groups and glutathione excretion. Metabolic adaptation involved tricarboxylic acid (TCA) cycle activation, acceleration of mitochondrial respiration and a redistribution of electron transfer pathways, with an increase in the contribution of the alternative oxidase and rotenone-insensitive dehydrogenase. Changes in redox status and apparent oxidative stress may be necessary to the shift to adaptive metabolic pathways, ensuring normal mitochondrial function and adenosine triphosphate (ATP) levels. The consumption of intracellular glutathione levels during the filamentation process may thus be the price paid by C. albicans for survival in the conditions encountered in the host.     

Kolaviron,a biflavonoid complex of Garcinia kola seeds modulates apoptosis by suppressing oxidative stress and inflammation in diabetes-induced nephrotoxic rats

Diabetic nephropathy is a complex disease that involves increased production of free radicals which is a strong stimulus for the release of pro-inflammatory factors. We evaluated the renal protective effect of kolaviron (KV) – a Garcinia kola seed extract containing a mixture of 5 flavonoids, in diabetes-induced nephrotoxic rats. Male Wistar rats were divided into 4 groups: untreated controls (C); normal rats treated with kolaviron (C + KV); untreated diabetic rats (D); kolaviron treated diabetic rats (D + KV). A single intraperitoneal injection of streptozotocin (STZ, 50 mg/kg) was used for the induction of diabetes. Renal function parameters were estimated in a clinical chemistry analyzer. Markers of oxidative stress in the kidney homogenate were analyzed in a Multiskan Spectrum plate reader and Bio-plex Promagnetic bead-based assays was used for the analysis of inflammatory markers. The effect of kolaviron on diabetes-induced apoptosis was assessed by TUNEL assay. In the diabetic rats, alterations in antioxidant defenses such as an increase in lipid peroxidation, glutathione peroxidase (GPX) activity and a decrease in catalase (CAT) activity, glutathione (GSH) levels and oxygen radical absorbance capacity (ORAC) were observed. There was no difference in superoxide dismutase (SOD) activity. Diabetes induction increased apoptotic cell death and the levels of interleukin (IL)-1β and tumor necrosis factor (TNF)-α with no effect on IL-10. Kolaviron treatment of diabetic rats restored the activities of antioxidant enzymes, reduced lipid peroxidation and increased ORAC and GSH concentration in renal tissues. Kolaviron treatment of diabetic rats also suppressed renal IL-1β. The beneficial effects of kolaviron on diabetes-induced kidney injury may be due to its inhibitory action on oxidative stress, IL-1β production and apoptosis.     

Depot-specific modulation of adipokine levels in rat adipose tissue by diet-induced obesity: The effect of aerobic training and energy restriction

The present study examined the effects of aerobic training and energy restriction on adipokines levels in mesenteric (MEAT) and retroperitoneal (RPAT) white adipose tissue from obese rats. Male Wistar rats were fed with standard laboratory diet (Control group) or high fat diet (HFD). After 15 weeks, HFD rats were randomly assigned to the following groups: rats submitted to HFD, which were sedentary (sedentary HFD, n = 8) or trained (trained HFD, n = 8); or submitted to energy-restriction (ER), which were sedentary (sedentary ER, n = 8) or trained (trained ER, n = 8). Trained rats ran on a treadmill at 55% VO_2max for 60 min/day, 5 days/week, for 10 weeks. ER rats were submitted to a reduction of 20% daily caloric ingestion compared to the Control group. ER and aerobic training decreased body weight, MEAT and RPAT absolute weight, and fat mass. IL-6, IL-10 and TNF-α levels were decreased and adiponectin did not change in RPAT in response to ER protocol. On the other hand, ER and the aerobic training protocol decreased IL-6, TNF-α and adiponectin levels in MEAT. Absolute MEAT weight showed a positive correlation with IL-6 (r = 0.464), TNF-α (r = 0.508); and adiponectin (r = 0.342). These results suggest a tissue-specific heterogeneous response in adipokines level. The combination of the protocols (aerobic training and energy restriction) did not induce an enhanced effect.     

Activation of foal neutrophils at different ages by CpG oligodeoxynucleotides and Rhodococcus equi

Toll-like receptor 9 (TLR9) activation stimulates protective immune responses against intracellular pathogens by phagocytes, including neutrophils. This study examined TLR9-mediated neutrophil activation in neonatal foals. Unmethylated CpGs, ligands for TLR9, were used to stimulate equine neutrophils, either purified or in contact with other peripheral blood leukocytes. Rhodococcus equi was used as another stimulus in parallel. TLR9 mRNA was constitutively expressed at a similar level in purified equine neutrophils across different ages from birth to adulthood, and expression was not affected by either CpG or R. equi. Purified foal neutrophils were directly sensitive to CpG stimulation, reflected by enhanced reactive oxygen species generation following fMLP stimulation, and by expressing significantly (P < 0.05) greater mRNA of IFN-γ, IL-8, IL-12p35, and significantly (P < 0.05) decreased TNF-α mRNA. In comparison, purified foal neutrophils stimulated by R. equi showed significantly (P < 0.05) increased mRNA production of IL-6, IL-8, IL-23p19, and TNF-α. Neutrophils co-cultured with other leukocytes expressed a distinct profile of cytokine mRNA than purified neutrophils in response to CpG stimulation, whereas the profile was very similar following R. equi stimulation irrespective of neutrophil purity. When co-cultured with other leukocytes, foal neutrophils were significantly (P < 0.05) activated at birth by B-class CpGs and produced IL-6, IL-8, IL-12p40, and IL-23p19 at similar magnitudes to those at 2 months of age. In foal neutrophils at birth, R. equi significantly (P < 0.05) induced all cytokines stimulated by CpGs (except IL-12p40), as well as TNF-α. Our results indicate that foal neutrophils were sensitive to CpG or R. equi activation as early as at birth, and that B-class CpGs enhanced foal neutrophil functions in vitro.     

Interaction between vitamin B6 and source of selenium on the response of the selenium-dependent glutathione peroxidase system to oxidative stress induced by oestrus in pubertal pig

This study aimed to assess the interaction between vitamin B₆ and selenium (Se) for the flow of Se towards the Se-dependent glutathione peroxidase (GPX) system in response to oxidative stress naturally induced by oestrus in a pubertal pig model. At first oestrus, forty-five gilts were randomly assigned to the experimental diets (n = 9/group): basal diet (CONT); CONT + 0.3 mg/kg of Na-selenite (MSeB₆0); MSeB₆0 + 10 mg/kg of HCl-B₆ (MSeB₆10); CONT + 0.3 mg/kg of Se-enriched yeast (OSeB₆0); and OSeB₆0 + 10 mg/kg of HCl-B₆ (OSeB₆10). Blood samples were collected at each oestrus (long-term profiles), and daily from day −4 to +3 (slaughter) of the fourth oestrus (peri-oestrus profiles) after which liver, kidneys, and ovaries were collected. For long-term profiles, CONT had lower blood Se than Se-supplemented gilts (p < 0.01) and OSe was higher than MSe (p < 0.01). Lower erythrocyte pyridoxal-5-phosphate was found in B₆0 than B₆10 (p < 0.01). No treatment effect was observed on GPX activity. For peri-oestrus profiles, treatment effects were similar to long-term profiles. Treatment effects on liver Se were similar to those for long-term blood Se profiles and OSe had higher renal Se concentrations than MSe gilts (p < 0.01). Gene expressions of GPX1, GPX3, GPX4, and selenocysteine lyase in liver and kidney were greatest in OSeB₆10 gilts (p < 0.05). These results suggest that dietary B₆ modulate the metabolic pathway of OSe towards the GPX system during the peri-oestrus period in pubertal pigs.     

Protective effect of Piper betle leaf extract against cadmium-induced oxidative stress and hepatic dysfunction in rats

The present study was undertaken to examine the attenuative effect of Piper betle leaf extract (PBE) against cadmium (Cd) induced oxidative hepatic dysfunction in the liver of rats. Pre-oral supplementation of PBE (200 mg/kg BW) treated rats showed the protective efficacy against Cd induced hepatic oxidative stress. Oral administration of Cd (5 mg/kg BW) for four weeks to rats significantly (P > 0.05) elevated the level of serum hepatic markers such as serum aspartate transaminase (AST), serum alanine transaminase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), gamma-glutamyl transpeptidase (GGT), bilirubin (TBRNs), oxidative stress markers viz., thiobarbituric acid reactive substances (TBARS), lipid hydroperoxides (LOOH), protein carbonyls (PC) and conjugated dienes (CD) and significantly (P > 0.05) reduced the enzymatic antioxidants viz., superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), glutathione reductase (GR) and glucose-6-phosphate dehydrogenase (G6PD) and non-enzymatic antioxidants Viz., reduced glutathione (GSH), total sulfhydryls (TSH), vitamin C and vitamin E in the liver. Pre-oral supplementation of PBE (200 mg/kg BW) in Cd intoxicated rats, the altered biochemical indices and pathological changes were recovered significantly (P > 0.05) which showed ameliorative effect of PBE against Cd induced hepatic oxidative stress. From the above findings, we suggested that the pre-administration of P. betle leaf extract exhibited remarkable protective effects against cadmium-induced oxidative hepatic injury in rats.     

Dietary selenium requirements based on tissue selenium concentration and glutathione peroxidase activities in old female rats

Dietary nutrient requirements for older animals have been studied far less than have requirements for young growing animals. To determine dietary selenium (Se) requirements in old rats, we fed female weanling rats a Se-deficient diet (0.007 μg Se/g) or supplemented rats with graded levels of dietary Se (0–0.3 μg Se/g) as Na₂SeO₃ for 52 weeks. At no point did Se deficiency or level of Se supplementation have a significant effect (P>0.05) on growth. To determine Se requirements, Se response curves were determined for 7 Se-dependent parameters. We found that minimum dietary Se requirements in year-old female rats were at or below 0.05 μg Se/g diet based on liver Se, red blood cell glutathione peroxidase (Gpx1) activity, plasma Gpx3 activity, liver and kidney Gpx1 activity, and liver and kidney Gpx4 activity. In conclusion, this study found that dietary Se requirements in old female rats were decreased at least 50% relative to requirements found in young, rapidly growing female rats. Collectively, this indicates that the homeostatic mechanisms related to retention and maintenance of Se status are still fully functional in old female rats.     

Oxidative stress biomarkers indicate sublethal health effects in a sentinel small mammal species,the deer mouse (Peromyscus maniculatus), on reclaimed oil sands areas

Oxidative stress biomarkers can provide highly relevant insights into the physiological state of an organism. We compared endogenous oxidative stress biomarkers (lipid peroxidation and glutathione redox status) in the liver and testes as well as the hepatic antioxidant vitamins A and E in deer mice (Peromyscus maniculatus) collected from a reclaimed mine site on the Athabasca Oil Sands Region (northern Alberta, Canada), with those from a non-industrial reference site within the same natural macroregion. Both glutathione redox and vitamin A status in the liver as well as glutathione redox status in the testes were disrupted in mice from the reclaimed site, indicating oxidative stress in these organs. Increased oxidative stress in the liver was associated with greater exposure to Co, Se, and Tl and contributed to poorer body condition and lowered testis size in animals from the reclaimed site (data from companion study). These results confirm health effects and biological costs in this native, sentinel small mammal from exposure to pollutants at the reclaimed mine site. This work provides compelling information and insight into the value of oxidative stress biomarkers as physiological tools that can indicate the health status and fitness of local wild animals. In particular, this approach can be used by risk assessors and other stakeholders from the oil sands region in future environmental risk assessments to improve wildlife management and conservation practices.     

Ganoderma atrum polysaccharide attenuates oxidative stress induced by d-galactose in mouse brain

AimsGanoderma atrum polysaccharide (PSG-1), the main constituent of G. atrum, has been reported to attenuate oxidative stress in vitro. The aim of this study was to investigate whether PSG-1 has a protective effect on the brain against oxidative stress induced by d-galactose (D-gal) in vivo.Main methodsMice were intraperitoneally (i.p.) injected with D-gal (100 mg/kg body weight) once daily for 10 weeks. From the seventh week, D-gal-treated mice received PSG-1 (50, 100, or 150 mg/kg body weight) once daily for the last 4 weeks. The activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GSH-Rd), and the contents of glutathione (GSH), glutathione disulfide (GSSG) and malondialdehyde (MDA) in the brain were measured using different biochemical methods to evaluate the changes of the antioxidant ability in the PSG-1 treated mice. Apoptosis, reactive oxygen species (ROS) and calcium levels were determined by flow cytometry.Key findingsAdministration of PSG-1 significantly reduced apoptosis in the mouse brain in a dose-dependent manner. PSG-1-evoked reduction of apoptosis was associated with the decrease of MDA and GSSG contents, and the increase of SOD, CAT, GPx and GSH-Rd activities, and GSH contents. PSG-1 treatment was also found to attenuate ROS production and calcium accumulation.SignificancePSG-1 has a potential to be used as a novel therapeutic agent for the protection of aging brain tissue against oxidative damage by modifying the redox system and maintaining calcium homeostasis.     

Suppressing inflammatory cascade by cyclo-oxygenase inhibitors attenuates quinolinic acid induced Huntington's disease-like alterations in rats

AimsThe aim of this study was to investigate the protective effects of cyclo-oxygenase inhibitors against quinolinic acid (QA) induced Huntington's disease-like alterations in rats.Main methodsQuinolinic acid (300 nmol) was administered intrastriatally into the striatum to induce Huntington's disease-like alteration. Cyclo-oxygenase inhibitors celecoxib (15 and 30 mg/kg) and meloxicam (10 and 20 mg/kg) were given for 21 days. In behavioral assessment locomotor, rotarod, and balance beam walk performances were assessed. Oxidative stress, mitochondrial dysfunction, proinflammatory cytokines and caspase-3 were assessed on day 21 after behavioral assessments.Key findingsIntrastriatal quinolinic acid (300 nmol) administration significantly altered the body weight, motor coordination, and induced oxidative damage (as indicated by the increase in lipid peroxidation and nitrite concentration) in the striatum as compared to sham group. Besides quinolinic acid (300 nmol) significantly depleted the mitochondrial enzyme complex levels and increased TNF-α, IL-6 and caspase-3 (marker of apoptotic cell death) levels in the striatum. Chronic treatment with celecoxib (15 and 30 mg/kg) significantly attenuated the quinolinic acid-induced behavioral and biochemical alterations, while meloxicam was able to reverse behavioral alterations at higher dose (20 mg/kg) as compared to the quinolinic acid treated group. Chronic treatment with the selective COX-2 inhibitors significantly restored the mitochondrial enzyme complex activities as well as attenuated TNF-α, IL-6 and caspase-3 levels as compared to the quinolinic acid treated group.SignificanceResults of the present study demonstrate the protective effect of cyclo-oxygenase inhibitors in the experimental models of Huntington's disease; and further provide evidence toward the involvement of neuroinflammatory cascade in the pathogenesis of Huntington's disease.