Thorium exerts hazardous effects on some neurotransmitters and thyroid hormones in adult male rats

Tannic acid ameliorates the hazards effect of beryllium induced neuro-alterations and oxidative stress in adult male rats

Background

Tannic acid (TA) is one of the most consumed and famous polyphenols with a widespread attention in the medical field according to its unique structural, pharmaceutical, physicochemical, antioxidant and other biological features. A rare study was conducted on the hazard effect of beryllium (Be) on the central nervous system.

Aims

This study aims to show the ability of beryllium to cross the blood brain barrier. Demonstrate the effect of beryllium and tannic acid separately or with each other on brain ions (Na+, K+, Ca++) and on norepinephrine, dopamine, serotonin, finally on the glutathione and malondialdehyde.

Animals grouping

Seventy-two rats were divided into four groups as control, Be, TA, and Be+TA where Be was injected intraperitoneally as 1 mg/Kg b. wt, TA was orally administrated as 5% in aquas solution.

Results

The administration of beryllium showed its ability to cross the blood brain barrier and accumulated in cortex > cerebellum>hypothalamus also, a significant increase in Na+, Ca++ cooperated with a significant decrease in K+ ions content was observed. Norepinephrine, dopamine, and serotonin showed a general significant decrease in their content joined with a significant decrease in glutathione (GSH) and elevation in malondialdehydes (MDA) because of Be intoxication. On the other hands the daily oral administration of tannic acid showed a general significant decrease in Na+, Ca++ ions content parallel with a significant increase K+ also, a non-significant change in the three measured neurotransmitters was noticed.

Conclusion

Tannic acid showed a mitigation effect against Be intoxication which may regarded to the tannic acid antioxidant, chelating effect.

Neurological study on the effect of CeNPs and/or La Cl3 on adult male albino rats

Lanthanides are a group of 15 elements (8 heavy and 7 light) grouped for their proximity in the chemical and physical properties. Recently, this group of elements has received great attention because of their importance, and their entrance into many industrial technologies making the probability of the living organisms' exposure to it increase. The present study aims to study ability of cerium nanoparticles (CeNPs) or lanthanum (LaCl3) to cross the blood brain barrier also, investigate their neuro effect separately or together on some parameters in six brain areas (cortex, cerebellum, hippocampus, striatum, midbrain, and hypothalamus) of the adult male albino rats. The results showed the ability of both elements to distribute and accumulate in the different brain areas. Also, the results of CeNPs or LaCl3 treatment were in the same line where each element caused a significant decrease in norepinephrine (NE), dopamine (DA), serotonin (5-HT) and GABA accompanied with a significant increase in 5- hydroxyl indoleacetic acid (5-HIAA) glucose level. On the other hand, GSH and MDA showed a significant decrease after CeNPs treatment while, with LaCl3 treatment, MDA showed a significant increase in the different brain areas after 3 weeks of treatment. The coadministration of CeNPs and La Cl3 caused an ameliorating effect in all the tested parameters. In conclusion, from the previous studies the effects of lanthanides in the present study may be in part due to its effect on the release or turnover of neurotransmitters and insulin secretion. Finally, the ameliorative effect of CeNPs may be regarded as its high activity to scavenge the free radicals.

Humic acid attachment on chitosan-modified silica gel as an economical, efficient, and selective adsorbent for thorium and uranium removal

A novel, low-cost adsorbent material was prepared by the immobilization of humic acid on a silica gel surface coated with cross-linked chitosan (SiChiHA). The adsorbent was developed to remove selectively of Th(IV) and U(VI) from aqueous solution, including their pre-concentration and separation from lanthanides and high salinity conditions. A simple waste-less humic acid immobilization method was shown to be successful based on FT-IR, SEM-EDS, and zeta potential characterization results. The adsorbent was found to be stable over a wide pH range, with the highest capacities obtained at pH 3.5 (Th(IV)) and pH 5 (U(VI)). Langmuir model calculations yielded a maximum capacity of 30.6 mg g^-1 and 75.4 mg g^-1 for Th(IV) and U(VI). The adsorption process was found to be rapid (half concentration was removed within 10 min) and best described by a pseudo-second order rate equation. Increasing NaCl concentration up to 2 mol L^-1 or lanthanide concentration up to 100 times did not significantly affect the removal efficiency for either Th(IV) of U(VI). Both elements could be sequentially separated by elution with ammonium citrate and nitric acid, respectively. The adsorption-desorption experiment showed that the adsorbent could be used for at least five cycles without significant capacity loss. This study provides insight into the development of low-cost adsorbent with practical functionality, including separation and regeneration ability, the advantageous properties scarcely reported in low-cost adsorbent literature.

Actinide Decorporation: A Review on Chelation Chemistry and Nanocarriers for Pulmonary Administration

Chelation is considered the best method for detoxification by promoting excretion of actinides (Am, Np, Pu, Th, U) from the human body after internal contamination. Chemical agents that possess carboxylic acid or hydroxypyridinonate groups play a vital role in actinide decorporation. In this review article, we provide considerable background details on the chelation chemistry of actinides with an aim to formulate better decorporation agents. Nanocarriers for pulmonary delivery represent an exciting prospect in the development of novel therapies for actinide decorporation that both reduce toxic side effects of the agent and improve its retention in the body. Recent studies have demonstrated the benefits of using a nebulizer or an inhaler to administer chelating agents for the decorporation of actinides. Effective chelation therapy with large groups of internally contaminated people can be a challenge unless both the agent and the nanocarrier are readily available from strategic national stockpiles for radiological or nuclear emergencies. Sunflower lecithin is particularly adept at alleviating the burden of administration when used to form liposomes as a nanocarrier for pulmonary delivery of diethylenetriamine-pentaacetic acid (DTPA) or hydroxypyridinone (HOPO). Better physiologically-based pharmacokinetic models must be developed for each agent in order to minimize the frequency of multiple doses that can overload the emergency response operations.

Role of calcium ion channels and cytoskeletal proteins in Thorium-232 induced toxicity in normal human liver cells (WRL 68) and its validation in swiss mice

Hepatic disorders reported in humans exposed to Thorium-232 (Th-232) rationalizes the present study investigating the toxicological response of normal human liver cells (WRL 68) and its validation in Swiss mice. Cell count analysis of WRL 68 cells-treated with Th-nitrate (1-200 μM) estimated IC50 of ∼24 μM (at 24 h) and 35 μM (at 48 h). Analysis of cell viability (trypan blue assay) showed the IC50 of ∼172 μM. Phase contrast bright-field microscopy revealed Th-induced morphological changes and cell-released microvesicle-like structures in extracellular space. Th-estimation by ICP-MS (Inductively-coupled plasma mass-spectrometry) showed uptake of Th by cells as a function of concentration and incubation time. Employing DTPA as a chelating agent in cell harvesting solution, cell-internalized/strongly-bound Th was estimated to be ∼42% of total incubated Th. Th-uptake studies in the presence of ion-channel specific inhibitors (e.g. nifedipine, thapsigargin) revealed the role of plasma membrane calcium channels and cytoplasmic calcium in modulating the Th-uptake. Transmission electron microscopy of Th-treated cells showed cell-derived extracellular vesicles, alterations in the shape and size of nucleus and mitochondria as well as cytoplasmic inclusions. The order of Th accumulation in various sub-cellular protein fractions was found to be as cytoskeleton (43%) > cytoplasmic (15%) > chromatin (7%) > nuclear (5%) & membrane (5%). Immunofluorescence analysis of WRL 68 cells showed that Th significantly altered the expression of cytoskeleton proteins (F-actin and keratin), which was further validated in liver tissues of Swiss mice administered with Th-232. Findings herein highlight the role of calcium channels and cytoskeleton in Th-induced toxicity. Keywords: Thorium toxicity; Liver cells; Calcium channels; Sub-cellular targets, Cytoskeleton; Swiss Mice.

Renal protective effects of grape seed extract treatment against Eltroxin-induced hyperthyroidism, kidney damage, and oxidative stress in male mice

The present study aimed to investigate the influence of grape seed extract (GSE) in renal toxicity, oxidative stress, and Bcl-2 expressions in Eltroxin-induced hyperthyroidism to male mice. GSE was evaluated through oral administration to male mice at dose 50 mg/kg daily for 3 consecutive weeks. Eltroxin (100 μg/kg) was administered to mice for 3 weeks, and the mice were posttreated with GSE for another 3 weeks. Results revealed that GSE administered to normal mice did not produce any signs of toxicity and did not cause any biochemical or histopathological changes. Posttreatment of Eltroxin-induced hyperthyroidism mice with GSE daily for 3 weeks improved all examined biochemical or histopathological features. Oral GSE can significantly normalize the elevated level of T3 and T4 in hyperthyroidism animals and elevated the reduced levels of TSH. Moreover, serum urea, creatinine, and electrolyte levels were significantly improved. GSE showed a potent antioxidant capacity in all oxidative stress markers assays (TBARS, reduced GSH, GST, SOD, and CAT) of kidney tissue homogenates. Furthermore, histopathological examination of kidney tissue of Eltroxin + GSE-treated group confirms the potential nephroprotective effect of GSE through increasing the anti-apoptotic marker Bcl-2.

Saussurea lappa root extract ameliorates the hazards effect of thorium induced oxidative stress and neuroendocrine alterations in adult male rats

The present study was aimed to estimating the effect of Saussurea lappa (costus) root extract on thorium accumulation in different brain regions (cerebral cortex, cerebellum, and hypothalamus) of adult male albino rats and also to evaluate the antioxidant effect and thyroid gland modulation activity of costus following thorium toxicity. Adult male rats were randomly allocated into four groups; control group receiving saline (0.9% NaCl), thorium group receiving an intraperitoneal (i.p.) injection of thorium nitrate (Th; 6.3 mg/kg bwt), costus group receiving an oral administration of costus extract at 200 mg/kg bwt and costus + thorium group receiving costus 1 h before thorium injection. Thorium injection in rats for 28 days resulted in the accumulation of Th maximally in the cerebellum followed by the cerebral cortex and then in the hypothalamus. The accumulation of Th was associated with significant disturbance in sodium and potassium ions. A significant decrease in monoamines was also observed in different brain regions. Furthermore, the results indicated that Th-induced oxidative stress evidenced by increased lipid peroxidation and nitric oxide and decrease the glutathione content. Additionally, Th caused a significant increase in thyroid-stimulating hormone (TSH), triiodothyronine (T3), and thyroxine (T4) levels in the serum of rats. However, the pre-administration of costus alleviated all of those disturbances. Our results revealed that costus extract exerted its protective effect mainly through potentiating the antioxidant defense system.