Increased oxidant stress and decreased antioxidant status in erythrocytes of rats fed with zinc-deficient diet

Assessment of oxidative/nitrosative stress and antioxidant capacity in children with epilepsy

Background: The underlying pathophysiological mechanisms in epilepsy, one of the most common neurological diseases, are still unknown. Oxidative/nitrosative stress is considered a possible mechanism involved in epileptogenesis. The production of reactive oxygen species (ROS) and reactive nitrogen species (RNS) is involved in the pathogenesis of signal regulation, cellular damage and central nervous system conditions in living organisms. In this study, we aimed to compare peoxynitrite (ONOO-), a marker of nitrosative stress, total oxidant status (TOS), total antioxidant status (TAS), oxidative stress index (OSI) and 8-hydroxy-2-deoxyguanosine (8-OHdG), DNA damage marker, levels in epileptic patients receiving monotherapy and polytherapy with the healthy control group.Methods: The study included 120 patients with diagnosis of epilepsy and 40 healthy volunteers as controls. The TOS, TAS, OSI, ONOO- and 8-OHdG were studied in all groups.Results: The study group included 30 girls (50%) and 30 boys (50%) receiving monotherapy and 31 girls (51.7%) and boys 49.3%) receiving polytherapy while control group included 19 girls (47.5%) and 21 boys (52.5%). The TOS and OSI values were found to be significantly higher in polytherapy group when compared to monotherapy and control groups). The ONOO- values were found to be significantly lower in polytherapy group when compared to monotherapy and control groups. In addition, ONOO- values were found to be higher in monotherapy group than controls. There was no significant difference in 8-OHdG values between the groups.Conclusions: Significant increases were observed in TOS and OSI parameters in polytherapy group when compared to monotherapy and control groups, suggesting that antiepileptic treatment enhances oxidative stress. Lack of significant difference in 8-OHdG suggested that the treatment is effective in patients and that no DNA damage occurred yet.

Zinc Deficiency Exacerbates Bisphenol A-Induced Hepatic and Renal Damage: Delineation of Molecular Mechanisms

Zinc (Zn) plays an important role in the maintenance of redox status in the biological system. Zn deficiency has been found to be associated with negative effects on the functioning of many organ systems, including hepatic and renal systems. Bisphenol A (BPA) can alter Zn homeostasis and perturb the physiological system by provoking oxidative stress, which can lead to damage of different organs such as reproductive, immune, neuroendocrine, hepatic and renal systems. The present study aims to investigate the toxicity of BPA in Zn deficient condition in the liver and kidney of rat and to correlate its synergistic actions. Zn deficiency was induced by feeding Zn-deficient diet (ZDD), and BPA was administered orally (100 mg/kg/d). Male Sprague-Dawley rats were divided into four groups: NPD + Vehicle (normal feed and water), NPD + BPA (100 mg/kg/d), ZDD + Vehicle (fed with Zn-deficient diet only) and ZDD + BPA (Zn-deficient diet + BPA; 100 mg/kg/d) for 8 weeks. Biochemical, histopathological, TUNEL assay and protein expression profiles were determined to decipher the oxidative damage induced by ZDD and the toxicant BPA. Expression profile of nuclear factor erythroid 2-related factor 2, proliferating cell nuclear antigen, kelch-like ECH-associated protein 1, superoxide dismutase-1, metallothionein and apoptosis incidence showed that ZDD and BPA have a synergistic exacerbation effect on the liver and kidney of rat.

Review of compounds that exhibit radioprotective and/or mitigatory effects after application of diagnostic or therapeutic ionizing radiation

PURPOSE

Exposure to ionizing radiation can be accidental or for medical purposes. Analyzes of the frequency of radiation damage in the general population, it has been determined that by far the most common are those that occur as a result of diagnostic or therapeutic procedures. Damage caused by radiation, either accidentally or for therapeutic purposes, can be reduced by the use of radioprotectors, mitigators or other therapeutic agents. A detailed research of the available literature shows that there is little systematized data of potentially radioprotective and/or mitigating effects of drugs from the personal therapy of patients during the application of therapeutic ionizing radiation. The aim of this paper is to present review of compounds, especially personal therapy drugs, that exhibit radioprotective and/or mitigating effects after the application of diagnostic or therapeutic ionizing radiation.

CONCLUSIONS

Given the widespread use of ionizing radiation for diagnostic and therapeutic purposes, there is a clear need to create a strategy and recommendations of relevant institutions for the use of radioprotectors and mitigators in everyday clinical practice, with individual evaluation of the patient's condition and selection of the compounds that will show the greatest benefit in terms of radioprotection.

Plant polyphenols as green sunscreen ingredients: A systematic review

BACKGROUND

Excessive exposure to ultraviolet radiation has harmful effects on human skin. At present, synthetic and mineral types of sunscreens used to protect against these harmful damages have been reported to cause negative health and environmental effects. The studies involving characterization and isolation of phytoconstituents from natural botanical sources are important to discover their potential beneficial effects on sunscreen development AIM: This systematic review provides specific and compiled information on the photoprotective properties of natural botanical sources for sunscreen development. The efforts in research and innovation are essential to ensure the safety and sustainability of plant-based sunscreen products.

METHODS

In this review, a total of 35 articles were selected using the Scopus database based on the inclusion and exclusion criteria RESULT: The significant correlation between total phenolic content, total flavonoid content, antioxidant activities, and sun protection factor were shown in these studies which confirmed the potential benefits of natural plants in sunscreen development.

CONCLUSIONS

In addition, natural botanical sources also exhibit excellent anti-tyrosinase, anti-aging, and anti-inflammatory activities. However, the biological activities of plants were dependent on the solvents used for extraction.

The Examination of the Influence of Caffeinated Coffee Consumption on the Concentrations of Serum Prolactin and Selected Parameters of the Oxidative-Antioxidant Balance in Young Adults: A Preliminary Report

We verified whether caffeinated coffee consumption influenced the concentrations of prolactin (PRL) and oxidative stress parameters: total antioxidant status (TAS), ferric reducing antioxidant power (FRAP), total oxidant status (TOS), oxidative stress index (OSI), advanced oxidation protein products (AOPP), uric acid (UA), total bilirubin (T-Bil), albumin (ALB), iron (Fe), calcium (Ca), magnesium (Mg), and inflammatory marker C-reactive protein (CRP)—in blood sera obtained at 15, 60, and 120 minutes after caffeinated coffee intake, in relation to the fasting point. The study participants were 33 young, healthy, nonsmoking volunteers (15 men, 18 women) aged 19-29 years. PRL concentrations significantly decreased ( $p<0.05$ ) after consumption, except at time point 15’ in men ( $p>0.05$ ). In women, FRAP levels significantly increased over time, and significant changes were also observed for UA at 120’ and ALB at 15’. In men, significant changes were found for levels of AOPP at 15’, T-Bil and ALB at 15’, iron at 60’ and 120’, and calcium at 120’. There were no significant differences in the levels of other examined parameters between the defined time points. In conclusion, the substances contained in caffeinated coffee decrease the level of prolactin and may also have an impact on selected parameters of oxidative stress, which could be the basis of future research focused on the identification of new therapeutic targets.

Thymoquinone: A Review of Pharmacological Importance, Oxidative Stress, COVID-19, and Radiotherapy

Widely consumed worldwide, Nigella sativa (NS) is a medicinal herb commonly used in various alternative medicine systems such as Unani and Tibb, Ayurveda, and Siddha. Recommended for regular use in Tibb-e-Nabwi (Prophetic Medicine), NS is considered one of the most notable forms of healing medicine in Islamic literature. Thymoquinone (TQ), the main component of the essential oil of NS, has been reported to have many properties such as antioxidant, anti-inflammatory, antiviral, and antineoplastic. Its chemical structure indicates antiviral potential against many viruses, including the hepatitis C virus, human immunodeficiency virus, and other coronavirus diseases. Interestingly, molecular docking studies have demonstrated that TQ can potentially inhibit the development of the coronavirus disease 2019 (COVID-19) by binding to the receptor site on the transmembrane serine proteinase 2 (the activator enzyme that attaches the virus to the cell). In addition, TQ has been shown to be effective against cancer cells due to its inhibitory effect by binding to the different regions of MDM2, according to the proposed molecular docking study. Detailed in this review is the origin of TQ, its significance in alternative medicine, pharmacological value, potential as a cancer anti-proliferative agent, use against the coronavirus disease 2019 (COVID-19), and treatment of other diseases.

Nigella sativa oil and thymoquinone reduce oxidative stress in the brain tissue of rats exposed to total head irradiation

Purpose: To evaluate the antioxidant and radio-protective effects of Nigella sativa oil (NSO) and thymoquinone (TQ) on radiation-induced oxidative stress in brain tissue.Materials and methods: Fifty-four Sprague-Dawley rats were divided into six groups to test the radio-protective effectiveness of Nigella sativa oil and thymoquine administered by either orogastric tube or intraperitoneal injection. Appropriate control groups were also studied.Results: Brain antioxidant capacity, as measured by the levels of total superoxide scavenger activity (TSSA), non-enzymatic superoxide scavenger activity (NSSA), superoxide dismutase, paraoxonase (PON) activities, total antioxidant status and total sulfhydryl (-SH) group, were lower in the irradiation (IR) only group while xanthine oxidase (XO) activity, total oxidant status (TOS), oxidative stress index (OSI) and lipid hydroperoxide (LOOH) levels were higher in the group compared with all other groups. Brain glutathione-S-transferase (GST) activity significantly decreased in the IR only group when compared with the control groups. Glutathione peroxidase (GSH-Px) activity was lower in the IR only, NSO plus IR, TQ plus IR groups when compared with the control group of TQ. Arylesterase (ARYL) activity was not statistically significant in the IR only group compared with all other groups.Conclusions: The results suggest that Nigella sativa oil (NSO) and its active component, TQ, clearly protect brain tissue from radiation-induced oxidative stress.

Urotensin 2 and Oxidative Stress Levels in Maternal Serum in Pregnancies Complicated by Intrauterine Growth Restriction

Background and objectives: In this study, the aim was to investigate Urotensin 2 (U-II) levels and oxidant/antioxidant system parameters in pregnancies with intrauterine growth restriction (IUGR). Materials and Methods: A total of 36 healthy, pregnant women who had not been diagnosed with IUGR and 36 pregnant women who had been diagnosed with IUGR at the Obstetrics and Gynecology Outpatient Clinic at Gaziantep University Hospital were enrolled in this study. The serum total antioxidant status (TAS), total oxidant status (TOS), thiol-disulfide levels, U-II measurements, and oxidative stress index (OSI) calculations were carried out at the biochemistry laboratory at Gaziantep University. Results: According to this study, there was no statistically significant difference between the group with IUGR and the control group of healthy, pregnant women in terms of total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), native thiol, total thiol, disulfide, disulfide/native thiol, disulfide/total thiol, native thiol/total thiol, and U-II values. There was, however, a positive linear correlation between TOS and total thiol levels in the group with IUGR (p = 0.021, r = 0.384), and a positive linear correlation between OSI and total thiol values in the control group (p = 0.049, r = 0.330). In addition, there was a negative correlation between disulfide levels and gestational weeks at birth in the group with IUGR (p = 0.027, r = 0.369). Conclusions: Consequently, there was no significant difference between the control group and the group with pregnancies complicated by idiopathic IUGR in terms of serum oxidant/antioxidant system parameters and U-II levels. It is necessary to conduct more extensive studies evaluating placental, maternal, and fetal oxidative stress in conjunction in order to investigate the role of oxidative stress in IUGR.

Optimization of dietary zinc for egg production and antioxidant capacity in Chinese egg-laying ducks fed a diet based on corn-wheat bran and soybean meal

The aim of this study was to evaluate the effect of zinc supplementation on productive performance and antioxidant status in laying ducks. Five-hundred-four laying ducks were divided into 7 treatments, each containing 6 replicates of 12 ducks. The ducks were caged individually and fed a corn-soybean meal and wheat bran basal diet (37 mg Zn/kg) or the basal diet supplemented with 15, 30, 45, 60, 75, or 90 mg Zn/kg (as zinc sulfate). During the early laying period of 10 d (daily egg production <80%), egg production, daily egg mass, and FCR increased quadratically with increasing dietary Zn levels (P < 0.05). The highest egg production and daily egg weight were obtained when 30 or 45 mg Zn/kg diet was supplemented, with lowest FCR. Similarly, the highest egg production and daily egg mass were observed in the group supplemented with 30 or 45 mg Zn/kg during the peak laying period of the subsequent 120 d (daily egg production >80%). Average egg weight and feed intake did not differ among the groups of graded Zn supplementation.The egg quality was not affected by dietary Zn, including the egg shape index, Haugh unit, yolk color score, egg composition, and shell thickness. The activities of plasma activities of total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-PX) increased in a quadratic manner (P < 0.001) with increasing supplemental Zn. Plasma concentration of Zn increased quadratically (P < 0.05) as dietary Zn increased. The hepatic activity of Cu/Zn-SOD and GSH-PX increased quadratically (P < 0.05) with increasing dietary Zn. Plasma Zn concentrations were positively correlated with activities of T-SOD (P < 0.05), and positively with plasma Cu. Plasma concentration of reduced glutathione was correlated with plasma Cu. In conclusion, supplementation of Zn at 30 or 45 mg/kg to a corn-wheat bran and soybean basal diet may improve the productive performance and enhance the antioxidant capacity.

Antioxidant Activity of Syringic Acid Prevents Oxidative Stress in l-arginine-Induced Acute Pancreatitis: An Experimental Study on Rats

The aim of this study was to investigate the possible protective role of antioxidant treatment with syringic acid (SA) on l-arginine-induced acute pancreatitis (AP) using biochemical and histopathologic approaches. A total of 30 rats were divided into 3 groups. The control group received normal saline intraperitoneally. The AP group was induced by 3.2 g/kg body weight l-arginine intraperitoneally, administered twice with an interval of 1 hour between administrations. The AP plus SA group, after having AP induced by 3.2 g/kg body weight l-arginine, was given SA (50 mg kg(-1)) in 2 parts within 24 hours. The rats were killed, and pancreatic tissue was removed and used in biochemical and histopathologic examinations. Compared with the control group, the mean pancreatic tissue total oxidant status level, oxidative stress index, and lipid hydroperoxide levels were significantly increased in the AP group, being 30.97 ± 7.13 (P < 0.05), 1.76 ± 0.34 (P < 0.0001), and 19.18 ± 4.91 (P < 0.01), respectively. However, mean total antioxidant status and sulfhydryl group levels were significantly decreased in the AP group compared with the control group, being 1.765 ± 0.21 (P < 0.0001) and 0.21 ± 0.04 (P < 0.0001), respectively. SA reduces oxidative stress markers and has antioxidant effects. It also augments antioxidant capacity in l-arginine-induced acute toxicity of pancreas in rats.

Therapeutic effects of thymoquinone in a model of neuropathic pain

Background

The goal of our study was to determine the therapeutic effects of thymoquinone in a dose-dependent manner in a model of neuropathic pain following an experimentally applied spinal cord injury (SCI).

Methods

Fifty female adult Wistar albino rats weighing between 220 and 260 g were included in the study and were divided into 5 groups as follows: Group S (sham), Group C (control), Group T100 (100 mg/kg thymoquinone), Group T200 (200 mg/kg thymoquinone), and Group T400 (400 mg/kg thymoquinone). To begin the experiment, SCI was applied to all groups (with the exception of the sham group) following a mechanical and heat–cold test. Two weeks later, the mechanical and heat–cold tests were repeated, and a single normal saline dose was given to the sham and control groups, whereas 3 varying doses of thymoquinone were given to the other groups. The mechanical and heat–cold tests were repeated at 30, 60, 120, and 180 minutes after receiving thymoquinone. Finally, the animals were put to death via the removal of intracardiac blood. The levels of nitric oxide, total oxidant status, total antioxidant status, paraoxonase, malondialdehyde, tumor necrosis factor-α, and interleukin-1β were determined in all of the blood samples.

Results

The withdrawal threshold and withdrawal latency values recorded from the mechanical and heat–cold allodynia measurements for all 3 thymoquinone groups were higher than that of the control group at all time points (ie, 30, 60, 120, and 180 minutes). There were no differences in these results between the 3 thymoquinone groups. The paraoxonase and total antioxidant status serum levels of all 3 thymoquinone groups were higher than those of the control group, whereas total oxidant status, nitric oxide, malondialdehyde, interleuken-1β, and tumor necrosis factor-α levels were lower in the 3 thymoquinone groups than in the control group.

Conclusions

Thymoquinone is beneficial for decreasing experimental neuropathic pain following SCI. However, increasing the dose does not change the effect.

Zinc administration modulates radiation-induced oxidative injury in lens of rat

Background:

The aim of this study was to evaluate the antioxidant role of zinc (Zn) against radiation-induced cataract in the rat lens after total cranial irradiation with a single 5 Gray (Gy) dose of gamma irradiation.

Materials and Methods:

Twenty-one Sprague-Dawley rats were used for the experiment. The control group did not receive Zn or irradiation but received 1-ml saline orally plus sham-irradiation. The irradiation (IR) group received 5 Gy gamma irradiation to the total cranium as a single dose plus 0.1 ml physiological saline intraperitoneally. The IR plus Zn group received irradiation to total cranium plus 10 mg/kg/day Zn intraperitoneally. Biochemical parameters measured in rat lenses were carried out using spectrophotometric techniques.

Results:

Lens total (enzymatic plus non-enzymatic) superoxide scavenger activity (TSSA), glutathione reductase (GRD), and glutathione-S-transferase (GST) activities significantly increased in the IR plus Zn groups when compared with the IR group. However, TSSA, GRD and GST activities were significantly lower in the IR group when compared with the control group. Lens non-enzymatic superoxide scavenger activity (NSSA) in the IR plus Zn group was significantly increased compared to that of the IR group. Lens xanthine oxidase (XO) activity in the IR group significantly increased compared to that of both the control and IR plus Zn groups.

Conclusion:

Zn has clear antioxidant properties and prevented oxidative stress by scavenging free radicals generated by ionizing radiation in rat lenses.

Zinc deficiency enhances the induction of micronuclei and 8-hydroxy-2'-deoxyguanosine via superoxide radical in bone marrow of zinc-deficient rats

The aim of the present study was to examine whether zinc (Zn) deficiency augmented the frequency of micronuclei, an indicator of chromosome aberration, and the induction of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker of cellular DNA damage derived from oxidative stress, in rat bone marrow cells or not. Both the frequency of micronuclei and the induction of 8-OHdG were significantly increased in rats fed with a Zn-deficient versus a standard diet for 6 weeks (p < 0.005). The supplementation of Zn with a standard diet for 4 weeks to rats fed with a Zn-deficient diet for 6 weeks restored the enhanced induction of micronuclei and 8-OHdG to levels comparable to those seen in rats fed with a standard diet for 10 weeks, indicating that the shortage of Zn in the body is involved in the induction of micronuclei and 8-OHdG. Again, the membrane-permeable superoxide dismutase mimetic superoxide scavenger, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl, treatment (100 μmol/kg, twice a day) for 10 days prior to the termination of dietary treatment reduced the induction of micronuclei and 8-OHdG in rats fed with a Zn-deficient diet for 6 weeks to levels comparable to those in rats fed with a standard diet for 6 weeks, indicating that superoxide radical participates in the induction of micronuclei and 8-OHdG. In fact, the endogenous superoxide scavenger, Cu/Zn superoxide dismutase, was significantly reduced in the bone marrow cells of rats fed with a Zn-deficient diet for 6 weeks when compared to those of rats fed with a standard diet for 6 weeks (p < 0.005). These observations demonstrate that Zn deficiency elevates the frequency of micronuclei and the induction of 8-OHdG through an increase in the biological action of the superoxide radical. This suggests an increase in carcinogenic initiation resulting from Zn deficiency-induced oxidative stress.

Zinc: dietary intake and impact of supplementation on immune function in elderly

The diet in the elderly does not provide a sufficient level of nutrients needed to maintain an adequate healthy status leading to micronutrient deficiencies and impaired immune response with subsequent development of degenerative diseases. Nutrient "zinc" is a relevant micronutrient involved in maintaining a good integrity of many body homeostatic mechanisms, including immune efficiency, owing to its requirement for the biological activity of many enzymes, proteins and for cellular proliferation and genomic stability. Old people aged 60-65 years and older have zinc intakes below 50% of the recommended daily allowance on a given day. Many causes can be involved: among them, altered intestinal absorption, inadequate mastication, psychosocial factors, drugs interactions, altered subcellular processes (zinc transporters (Zip and ZnT family), metallothioneins, divalent metal transporter-1). Zinc supplementation may remodel the immune alterations in elderly leading to healthy ageing. Several zinc trials have been carried out with contradictory data, perhaps due to incorrect choice of an effective zinc supplementation in old subjects showing subsequent zinc toxic effects on immunity. Old subjects with specific IL-6 polymorphism (GG allele carriers; named C-) are more prone for zinc supplementation than the entire old population, in whom correct dietary habits with foods containing zinc (Mediterranean diet) may be sufficient in restoring zinc deficiency and impaired immune response. We summarise the main causes of low zinc dietary intake in elderly reporting an update on the impact of zinc supplementation upon the immune response also on the basis of individual IL-6 polymorphism.

The comparison of neuroprotective effects of intrathecal dexmedetomidine and metilprednisolone in spinal cord injury

BACKGROUND

The purpose of this study is the investigation of the effects of intrathecally injected dexmedetomidine and methylprednisolone and their dominancy over one another in rats with generated Spinal Cord Injury (SCI).

METHODS

40, female, adult Wistar Albino rats weighing 220-260 g were included in the study. The rats were fixed with Intrathecal catheter (IT) and divided into four groups. All subjects were applied T7-10 laminectomy after catheter. Group S (n:10) was injected with IT 10 μL isotonic saline; Group C (n:10) with IT 10 μL isotonic saline after SCI; Group D (n:10) with IT one doze 10 μL of dexmedetomidine after SCI; Group M (n:10) IT one dose 10 μL of methylprednisolone. The subjects were sacrificed 72 h after this operation. The damaged area was removed biochemically and histopathologically examined.

RESULTS

Antioxidant and inflammatory parameters searched for in all damages tissue were statistically different in all groups from group S. They were different in group M and group D than group C (p < 0.001). After the comparison of group D and group M, PON and IL6 values were higher in group D (p = 0.003, p = 0.035) while the other two biochemical parameters were similar in both groups (Table 1). After histopathologic trials, edemas, bleeding and necrosis were found less in group S while at the most in group C (p < 0.001). In group M and group D, however, they were higher than group S and lower than group C (p < 0.001). After the comparison of group D and group M, while there was no difference in terms of edema necrosis, the amount of bleeding was lower in group D (p < 0.001) (Table 2).

CONCLUSIONS

It has been discovered that intrathecal use of dexmedetomidine caused neuroprotective effects similar to methylprednisolone.

Relation of oxidative stress, zinc and alkaline phosphatase in protein energy malnutrition

OBJECTIVE

To determine serum zinc (Zn), total anti-oxidant capacity (TAC), malondialdehyde (MDA), alkaline phosphatase (ALP) and albumin in protein energy malnutrition (PEM) and to analyse the appropriateness of using low weight-for-age for detecting childhood under-nutrition.

METHODS

This study comprised 455 children (355 malnourished and 100 normal). They were classified according to the Nutrition Subcommittee of Indian Academy of Pediatrics, Z-Score Classification and Composite Index of Anthropometric Failure. Serum Zn, TAC, MDA, ALP and albumin levels were determined.

RESULTS

The serum Zn, TAC, ALP and albumin levels were found to be significantly decreased and MDA levels were significantly increased in malnourished children as compared with control (P < 0.001).

CONCLUSION

The significant increase in serum MDA concentration associated with the decrease in serum TAC, Zn and ALP in malnourished children suggest that these children were potentially susceptible to high oxidative stress. Current study also suggest that conventional measures of detecting under-nutrition (low weight-for-age) may be missing out a considerable proportion of undernourished children present in the population.

Environmental characteristics and oxidative stress of inhabitants and patients with amyotrophic lateral sclerosis in a high-incidence area on the Kii Peninsula, Japan

OBJECTIVE

Although Oshima, in the Kii Peninsula of Japan, is located within a high incidence area of amyotrophic lateral sclerosis (ALS) (Koza/Kozagawa/Kushimoto area, K area), no patients with ALS were detected between 1960 and 1999. However, the incidence recently increased between 2000 and 2009. On Oshima, the source of drinking water was changed from a regional river/wells to the Kozagawa River in the K area in 1975. We speculate that this change in water source may have played a role in the recent increase in the incidence of ALS. The aim of this study is to find contributing factors that may have triggered the locally high incidence of ALS.

METHODS

We investigated a possible association between the mineral content of drinking water and serum and oxidative stress markers among patients with ALS in the K area (K-ALS), residents of Oshima and controls.

RESULTS

We found that the levels of Ca and Zn in the recent drinking water in Oshima are low and that the serum levels of Ca and Zn in the Oshima residents and patients with K-ALS were significantly lower, while the oxidative stress markers were significantly higher, than those of the controls. The serum Zn and urinary 8-OHdG/creatinine levels explained 60% and 58% of the variations among the three groups, respectively. The serum Zn levels were negatively correlated with the serum Cu levels in the patients with K-ALS, and the serum Cu levels exhibited a tendency to be positively correlated with the 8-OHdG/creatinine levels in both the patients with K-ALS (r: 0.64) and the residents free from K-ALS (r: 0.32, p<0.01).

CONCLUSION

Taken together, we suggest that the low levels of Ca and Zn in the drinking water are possibly associated with an imbalance of metal metabolism in Oshima residents and an increase in oxidative stress markers in patients with K-ALS, although the causative relationship is not clear. This is a cross-sectional study, and a prospective study is needed in the future.

Zinc and redox signaling: perturbations associated with cardiovascular disease and diabetes mellitus

Cellular signal transduction pathways are influenced by the zinc and redox status of the cell. Numerous chronic diseases, including cardiovascular disease (CVD) and diabetes mellitus (DM), have been associated with impaired zinc utilization and increased oxidative stress. In humans, mutations in the MT-1A and ZnT8 genes, both of which are involved in the maintenance of zinc homeostasis, have been linked with DM development. Changes in levels of intracellular free zinc may exacerbate oxidative stress in CVD and DM by impacting glutathione homeostasis, nitric oxide signaling, and nuclear factor-kappa B-dependent cellular processes. Zinc ions have been shown to influence insulin and leptin signaling via the phosphoinositide 3′-kinase/Akt pathway, potentially linking an imbalance of zinc at the cellular level to insulin resistance and dyslipidemia. The oxidative modification of cysteine residues in zinc coordination sites in proteins has been implicated in cellular signaling and regulatory pathways. Despite the many interactions between zinc and cellular stress responses, studies investigating the potential therapeutic benefit of zinc supplementation in the prevention and treatment of oxidative stress-related chronic disease in humans are few and inconsistent. Further well-designed randomized controlled trials are needed to determine the effects of zinc supplementation in populations at various stages of CVD and DM progression.

Low extracellular zinc increases neuronal oxidant production through nadph oxidase and nitric oxide synthase activation

A decrease in zinc (Zn) levels increases the production of cell oxidants, affects the oxidant defense system and triggers oxidant sensitive signals in neuronal cells. However, the underlying mechanisms are still unclear. This work tested the hypothesis that the increase in neuronal oxidants that occurs when cellular Zn decreases is mediated by the activation of the NMDA receptor. Differentiated PC12 cells were cultured in control, Zn-deficient or Zn-repleted media. The incubation in Zn deficient media led to a rapid increase in cellular calcium levels, which was prevented by a NMDA receptor antagonist (MK-801). Cellular calcium accumulation was associated with NADPH oxidase and nitric oxide synthase (NOS) activation, an increase in cell oxidant levels, and an associated activation of a redox-sensitive signal (AP-1). In cells incubated in the Zn deficient medium, NADPH oxidase activation was prevented by MK-801 and by a protein kinase C inhibitor. The rise in cell oxidants was prevented by inhibitors of NADPH oxidase, of the NOS and by MK-801. A similar pattern of inhibitor action was observed for zinc deficiency-induced AP-1 activation. Results demonstrate that a decrease in extracellular Zn leads to an increase in neuronal oxidants through the activation of the NMDAR that leads to calcium influx and to a calcium-mediated activation of protein kinase C/NADPH oxidase and NOS. Changes in extracellular Zn concentrations can be sensed by neurons, which using reactive oxygen and nitrogen species as second messengers, can regulate signaling involved in neuronal development and function.

The role of oxidative stress in amyotrophic lateral sclerosis and Parkinson's disease

We examined oxidative stress markers of 31 patients suffering from ALS, 24 patients suffering from PD and 30 healthy subjects were included. We determined the plasma levels of lipid peroxidation (malondialdehyde, MDA), of protein oxidative lesions (plasma glutathione, carbonyls and thiols) and the activity of antioxidant enzymes i.e. erythrocyte Cu,Zn-Superoxide dismutase (SOD), Glutathione peroxidase (GSH-Px) and catalase. MDA and thiols were significantly different in both neurodegenerative diseases versus control population. A trend for an enhancement of oxidized glutathione was noted in ALS patients. Univariate analysis showed that SOD activity was significantly decreased in ALS and GSH-Px activity was decreased in PD. After adjusting for demographic parameters and enzyme cofactors, we could emphasize a compensatory increase of SOD activity in PD. Different antioxidant systems were not involved in the same way in ALS and PD, suggesting that oxidative stress may be a cause rather than a consequence of the neuronal death.

Smoking and inflammatory bowel diseases: what in smoking alters the course?

Epidemiological studies provide strong evidence to confirm the correlation between cigarette smoking and inflammatory bowel diseases. This relationship is proved to be positive in Crohn's disease and negative in ulcerative colitis. What in smoking alters the course of inflammatory bowel diseases is still a mystery. Different smoking parts have different and may be opponent actions. Smoking has dual effects. Some of its activities are, sometimes, constructive as they are working in an antagonistic manner to the mechanism of the disease, such as reducing rectal blood flow and accordingly less recruitments of inflammatory mediators to the area of inflammation, enhancement of mucosal production, and consequently, strengthening the membranes, and inhibition of pro-inflammatory mediators' liberation and activity in subjects with ulcerative colitis. Yet the outcome of smoking actions may be affected by the existence of other cofactors. Odd factors, such as shortage of zinc in subjects with Crohn's disease, may facilitate liberation of pro-inflammatory mediators and their activities and accordingly exacerbates symptoms.

Cytosolic superoxide dismutase (SOD1) is critical for tolerating the oxidative stress of zinc deficiency in yeast

Zinc deficiency causes oxidative stress in many organisms including the yeast Saccharomyces cerevisiae. Previous studies of this yeast indicated that the Tsa1 peroxiredoxin is required for optimal growth in low zinc because of its role in degrading H₂O₂. In this report, we assessed the importance of other antioxidant genes to zinc-limited growth. Our results indicated that the cytosolic superoxide dismutase Sod1 is also critical for growth under zinc-limiting conditions. We also found that Ccs1, the copper-delivering chaperone required for Sod1 activity is essential for optimal zinc-limited growth. To our knowledge, this is the first demonstration of the important roles these proteins play under this condition. It has been proposed previously that a loss of Sod1 activity due to inefficient metallation is one source of reactive oxygen species (ROS) under zinc-limiting conditions. Consistent with this hypothesis, we found that both the level and activity of Sod1 is diminished in zinc-deficient cells. However, under conditions in which Sod1 was overexpressed in zinc-limited cells and activity was restored, we observed no decrease in ROS levels. Thus, these data indicate that while Sod1 activity is critical for low zinc growth, diminished Sod1 activity is not a major source of the elevated ROS observed under these conditions.