Therapeutic influence of zinc and ascorbic acid against lead induced biochemical alterations

(Ascorb)ing Pb Neurotoxicity in the Developing Brain

Lead (Pb) neurotoxicity is a major concern, particularly in children. Developmental exposure to Pb can alter neurodevelopmental trajectory and has permanent neuropathological consequences, including an increased vulnerability to further stressors. Ascorbic acid is among most researched antioxidant nutrients and has a special role in maintaining redox homeostasis in physiological and physio-pathological brain states. Furthermore, because of its capacity to chelate metal ions, ascorbic acid may particularly serve as a potent therapeutic agent in Pb poisoning. The present review first discusses the major consequences of Pb exposure in children and then proceeds to present evidence from human and animal studies for ascorbic acid as an efficient ameliorative supplemental nutrient in Pb poisoning, with a particular focus on developmental Pb neurotoxicity. In doing so, it is hoped that there is a revitalization for further research on understanding the brain functions of this essential, safe, and readily available vitamin in physiological states, as well to justify and establish it as an effective neuroprotective and modulatory factor in the pathologies of the nervous system, including developmental neuropathologies.

Dynamical properties of elemental metabolism distinguish attention deficit hyperactivity disorder from autism spectrum disorder

Attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are neurodevelopmental conditions of overlapping etiologies and phenotypes. For ASD, we recently reported altered elemental metabolic patterns in the form of short and irregular zinc and copper cycles. Here, we extend the application of these biomarkers of prenatal and early postnatal elemental metabolism to distinguish between individuals diagnosed with ADHD and/or ASD and neurotypical controls. We recruited twins discordant for ADHD, ASD and other neurodevelopmental diagnoses from national twin studies in Sweden (N = 74) diagnosed according to DSM-5 clinical consensus and standardized psychiatric instruments. Detailed temporal profiles of exposure to 10 metals over the prenatal and early childhood periods were measured using tooth biomarkers. We used recurrence quantification analysis (RQA) to characterize properties of cyclical metabolic patterns of these metals. Regularity (determinism) and complexity (entropy) of elemental cycles was consistently reduced in ADHD for cobalt, lead, and vanadium (determinism: cobalt, β = -0.03, P = 0.017; lead, β = -0.03, P = 0.016; and vanadium, β = -0.03, P = 0.01. Entropy: cobalt, β = -0.13, P = 0.017; lead, β = -0.18, P = 0.016; and vanadium, β = -0.15, P = 0.008). Further, we found elemental pathways and dynamical features specific to ADHD vs ASD, and unique characteristics associated with ADHD/ASD combined presentation. Dysregulation of cyclical processes in elemental metabolism during prenatal and early postnatal development not only encompasses pathways shared by ADHD and ASD, but also comprise features specific to either condition.

Dynamical features in fetal and postnatal zinc-copper metabolic cycles predict the emergence of autism spectrum disorder

Metals are critical to neurodevelopment, and dysregulation in early life has been documented in autism spectrum disorder (ASD). However, underlying mechanisms and biochemical assays to distinguish ASD cases from controls remain elusive. In a nationwide study of twins in Sweden, we tested whether zinc-copper cycles, which regulate metal metabolism, are disrupted in ASD. Using novel tooth-matrix biomarkers that provide direct measures of fetal elemental uptake, we developed a predictive model to distinguish participants who would be diagnosed with ASD in childhood from those who did not develop the disorder. We replicated our findings in three independent studies in the United States and the UK. We show that three quantifiable characteristics of fetal and postnatal zinc-copper rhythmicity are altered in ASD: the average duration of zinc-copper cycles, regularity with which the cycles recur, and the number of complex features within a cycle. In all independent study sets and in the pooled analysis, zinc-copper rhythmicity was disrupted in ASD cases. In contrast to controls, in ASD cases, the cycle duration was shorter (F = 52.25, P < 0.001), regularity was reduced (F = 47.99, P < 0.001), and complexity diminished (F = 57.30, P < 0.001). With two distinct classification models that used metal rhythmicity data, we achieved 90% accuracy in classifying cases and controls, with sensitivity to ASD diagnosis ranging from 85 to 100% and specificity ranging from 90 to 100%. These findings suggest that altered zinc-copper rhythmicity precedes the emergence of ASD, and quantitative biochemical measures of metal rhythmicity distinguish ASD cases from controls.

The Potency of Red Seaweed (Eucheuma cottonii) Extracts as Hepatoprotector on Lead Acetate-induced Hepatotoxicity in Mice

BACKGROUND

Lead is one of the most toxic metals, producing severe organ damage in animals and humans. Oxidative stress is reported to play an important role in lead acetate-induced liver injury.

AIM

This study was carried out to investigate the role of ethanol extract of Eucheuma cottonii in protecting against lead acetate-induced hepatotoxicity in male mice.

MATERIALS AND METHODS

The sample used fifty male mice which were divided into five groups: negative control (mice were given daily with Aquadest); positive control (mice were given daily with lead acetate 20 mg/kg body weight (BW) orally once in a day for 21 days); and the treatment group (mice were given E. cottonii extracts 200 mg, 400 mg, and 800 mg/kg BW orally once in a day for 25 days, and on the 4^th day, were given lead acetate 20 mg/kg BW 1 h after E. cottonii extract administration for 21 days). On day 25, the levels of serum glutamic oxaloacetic transaminase (SGOT), serum glutamic pyruvate transaminase (SGPT), alkaline phosphatase (ALP), malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GPx) were measured. The data of SGOT, SGPT, ALP, MDA, SOD, and GPx were analyzed with one-way ANOVA, followed by least significant difference test.

RESULTS

The results showed that oral administration of lead acetate 20 mg/kg BW for 21 days resulted in a significant increase in SGOT, SGPT, ALP, and MDA levels. Moreover, there was a significant decrease in SOD and GPx levels. Treatment with E. cottonii extracts of 800 mg/kg BW but not with 200 mg/kg BW and 400 mg/kg BW significantly (P < 0.05) decreased the elevated SGPT, SGOT, ALP, and MDA levels as compared to positive control group. Treatment with E. cottonii extracts of 800 mg/kg BW also showed a significant increase in SOD and GPx levels as compared to positive control group. Treating mice with lead acetate showed different histopathological changes such as loss of the normal structure of hepatic cells, blood congestion, and fatty degeneration whereas animals treated with lead acetate and E. cottonii extracts showed an improvement in these changes and the tissue appeared with normal structures.

CONCLUSION

It can be concluded that E. cottonii extracts could be a potent natural product and can provide a promising hepatoprotective effect against lead acetate-induced hepatotoxicity in mice.

SUMMARY

In summary, Oxidative stress reported to play an important role in lead acetate induced liver injury. The lead acetate treatment significantly increased the SGOT, SGPT, ALP, MDA, and decreased the antioxidant enzymes (SOD and GPx) in liver. The inhibition of antioxidant enzymes will increase free radicals in liver tissues and might induce liver injury in mice. The presence of ethanol extract of Eucheuma cottonii with lead acetate showed protective effects as attenuating lead acetate against its liver toxicity, and this may be due to the activity of ethanol extract of Eucheuma cottonii as antioxidant. The antioxidant enzymes (SOD and GPx) were increased, and MDA, SGOT, SGPT, ALP were decreased after ethanol extract of Eucheuma cottonii administration. The enzymatic activities (SOD and GPx) and MDA in mice can be used as biomarkers of heavy metal toxicity such as lead acetate. Histopathological view of liver sections in the lead acetate treated group showed the liver damage, as compared to the negative control group. However, administration of ethanol extract of Eucheuma cottonii significantly improved the histopathological in liver of lead acetate-treated mice. From the results of this study we concluded that the ethanol extract of Eucheuma cottonii could be a potent natural product provide a promising protective effect against lead acetate induced liver toxicity in mice. Abbreviations Used: SGOT: Serum Glutamic Oxaloacetic Transaminase, SGPT: Serum Glutamic Pyruvate Transaminase, ALP: Alkaline Phosphatase, MDA: Malondialdehyde, SOD: Superoxide Dismutase, GPx: Glutathione Peroxidase.

Effect of glycine on lead mobilization, lead-induced oxidative stress, and hepatic toxicity in rats

The effectiveness of glycine in treating experimental lead intoxication was examined in rats. Male Wistar rats were exposed to 3 g/L lead acetate in drinking water for 5 weeks and treated thereafter with glycine (100 and 500 mg/kg, orally) once daily for 5 days or glycine (1000 mg/kg, orally) once daily for 28 days. The effect of these treatments on parameters indicative of oxidative stress (glutathione and malondialdehyde levels), the activity of blood δ-aminolevulinic acid dehydratase, and lead concentration in blood, liver, kidney, brain, and bone were investigated. Liver samples were observed for histopathological changes. Glycine was found to be effective in (1) increasing glutathione levels; (2) reducing malondialdehyde levels; (3) decreasing lead levels in bone with the highest dose. However, glycine had no effect on lead mobilization when 100 and 500 mg/kg glycine were administered. In microscopic examination, glycine showed a protective effect against lead intoxication.