Alginate Beads Containing Cerium-Doped Mesoporous Glass and Curcumin: Delivery and Stabilization of Therapeutics.

Cancer is a leading cause of death worldwide, its genesis and progression are caused by homeostatic errors, and reactive oxygen species play a major role in promoting aberrant cancer homeostasis. In this scenario, curcumin could be an interesting candidate due to its versatile antioxidant, anti-inflammatory, anti-tumor, anti-HIV, and anti-infection properties. Nonetheless, the major problem related to its use is its poor oral bioavailability, which can be overcome by encapsulating it into small particles, such as hydrogel beads containing mesoporous silica. In this work, various systems have been synthesized: starting from mesoporous silica glasses (MGs), cerium-containing MGs have been produced; then, these systems have been loaded with 4 to 6% of curcumin. Finally, various MGs at different compositions have been included in alginate beads. In vitro studies showed that these hybrid materials enable the stabilization and effective delivery of curcumin and that a synergic effect can be achieved if Ce3+/Ce4+ and curcumin are both part of the beads. From swelling tests, it is possible to confirm a controlled curcumin release compartmentalized into the gastrointestinal tract. For all beads obtained, a curcumin release sufficient to achieve the antioxidant threshold has been reached, and a synergic effect of cerium and curcumin is observed. Moreover, from catalase mimetic activity tests, we confirm the well-known catalytic activity of the couple Ce3+/Ce4+. In addition, an extremely good radical scavenging effect of curcumin has been demonstrated. In conclusion, these systems, able to promote an enzymatic-like activity, can be used as drug delivery systems for curcumin-targeted dosing.

Dietary nano cerium oxide promotes growth, relieves ammonia nitrogen stress, and improves immunity in crab (Eriocheir sinensis).

Oxidative stress plays a crucial role in ammonia nitrogen toxicity. In this study, the beneficial effects of dietary nano cerium oxide (nano CeO2) as a potent antioxidant were examined in the Chinese mitten crab (Eriocheir sinensis). Crabs were fed a diet supplemented with 0, 0.2, 0.4, 0.8, 1.6, 3.2, 6.4, or 12.8 mg/kg nano CeO2 for 60 d. The optimum supplementation level of nano CeO2 that significantly increased weight gain rate and decreased feed coefficient was 0.8 mg/kg. This level also offered immune protection when crabs were kept under ammonia nitrogen stress and/or exposed to pathogen infection (Aeromonas hydrophila). Supplementation with 0.8 mg/kg of CeO2 (i) relieved pathological damage to the hepatopancreas; (ii) increased hemocyte counts, including total number of hemocytes, granulocytes, and hyalinocytes; (iii) decreased malondialdehyde content and increased antioxidant enzyme activities of superoxide dismutase and catalase in the hemolymph; (iv) increased the activities of lysozyme, acid phosphatase, and alkaline phosphatase in the hemolymph; and (v) increased gene and protein expression of cathepsin L in the hepatopancreas. Mortality increased when crabs were injected with bacteria under ammonia nitrogen stress, but dietary supplementation with 0.8 mg/kg nano CeO2 decreased the mortality rate. Thus, the results of this study suggested that dietary supplementation with nano CeO2 in crabs promoted growth and up-regulated immunity to bacterial infection under ammonia nitrogen stress.

A novel pharmacological approach of herbal mediated cerium oxide and silver nanoparticles with improved biomedical activity in comparison with Lawsonia inermis.

Diabetes mellitus is one of the threatening, non-communicable and chronic ailments worldwide since ancient times to the current stage of human existence. The utilization of nanoparticles as a medicine in the treatment of diabetes is an attractive proposition. In the present study, herbal mediated cerium oxide nanoparticles (HMCeO2 NPs), herbal mediated silver nanoparticles (HMAg NPs) and Lawsonia intermix extract (LIE) was evaluated for them for in-vivo hypoglycemic effect and compared the potency. The resulting HMCeO2 NPs, HMAg NPs and Lawsonia inermis have been characterized by different analytical equipments such as X-ray Diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Particle size analyzer (PSA), Field emission scanning electron microscope (FESEM) and High resolution transmission electron microscope (HRTEM). The synthesized NPs and Lawsonia inermis extract were assessed for toxicity by using acute oral toxicity using female albino mice (s) model by following OECD-425 guidelines. In in-vivo hypoglycemic animal model, the male wistar rats with weight varying between 180-200 gms were grouped as: normal control: did not receive any treatment, diabetic control (saline): received a single intraperitoneal dose of Streptozotocin (40 mg/kg), standard: received a single daily oral dose of 50 mg/kg body weight, HMCeO2 NPs: received single daily oral dose of 100 mg/kg, 200 mg/kg, HMAg NPs: received a single daily oral dose of 100 mg/kg, 200 mg/kg, and Lawsonia inermis: received a single daily oral dose of 100 mg/kg, 200 mg/kg. The herbal mediated NPs were considered safe as they have not shown toxic effects. From the current study results, it may conclude that, due to the advanced biological and pharmacological characters, the HMAg NPs depicted more potent hypoglycemic activity than that of LIE and CeO2 NPs.

Green synthesis of Ce2O3 NPs and determination of its antioxidant activity.

In this study, the authors presented synthesis of ceria nanoparticles (NPs) by the bio-reduction method and their antioxidative activity. Aqueous extract of Euphorbia (Euphorbia amygdaloides) was used as reducing and stabilising agents. They used aqueous extract of Euphorbia (E. amygdaloides) as reducing and stabilising agent. Ultraviolet-visible (UV-vis) absorption spectroscopy was used to monitor the quantitative formation of ceria NPs. They also addressed the characteristics of the obtained ceria NPs using scanning electron microscopy (SEM), X-ray diffraction (XRD) and transmitting electron microscope (TEM). The synthesised cerium (III) oxide (Ce2O3) NPs were initially noted through visual colour change from colourless pale yellow cerium (III) to light yellow cerium (IV) and further confirmed the band at 345 nm employing UV-vis spectroscopy. The average diameter of the prepared NPs was about 8.6-10.5 nm. In addition, the synthesised Ce2O3 NPs were tested for antioxidant and anti-bacterial activities using ferric reducing antioxidant power, cupric reducing antioxidant capacity, ferrous ions chelating activity, superoxide the anion radical scavenging and 2, 2'-azinobis 3-ethylbenzothiazol to-6-sulphonic acid scavenging activity. It could be concluded that Euphorbia (E. amygdaloides) extract can be used efficiently in the production of potential antioxidant and anti-bacterial Ce2O3 NPs for commercial applications.

Green synthesized cerium oxide nanoparticle: A prospective drug against oxidative harm.

Cerium oxide nanoparticle (CeONP) of size 2-3nm was synthesized by a new, simple and green method at ambient temperature, using cerium nitrate as prime precursor and Aloe vera leaf extract as stabilizing agent. Of the two oxidation states (+3) and (+4) of cerium, it was dominantly present in (+3) state in CeONP and cyclic conversion of Ce(III)O→Ce(IV)O→Ce(III)O by reaction with H2O2 implied uninterrupted antioxidant property of CeONP. Moreover, the higher oxygen defect in the crystal lattice produced particles with higher antioxidant activity. CeONP was found to neutralize the deleterious effects of H2O2 viz., cell death, generation of intracellular reactive oxygen species and loss of connectivity in mouse neural cells. Therefore, CeONP might have potential use in future as an anti-oxidant drug.

Effects of cerium oxide supplementation to laying hen diets on performance, egg quality, some antioxidant enzymes in serum and lipid oxidation in egg yolk.

This study was conducted to determine the effects of dietary cerium oxide levels (0, 100, 200, 300 or 400 mg/kg) on the laying performance, egg quality, some blood serum parameters and egg lipid peroxidation of laying hen. In total, one hundred and twenty 22-week-old brown Lohman LSL laying hens were randomly assigned to five groups equally (n = 24). Each treatment was replicated six times. Dietary supplementation of cerium oxide had no significant effect on feed intake and egg weight. The addition of cerium oxide to the laying hens' feed improved feed conversion ratio and increased (p < 0.05) egg production. Quality criteria of egg for except shell breaking strength were not affected by supplementing cerium oxide. In particular, supplementation of 200 and 300 mg/kg cerium oxide to the laying hens feed led to a significant (p < 0. 01) increase in egg shell breaking strength. Calcium and phosphorus concentration of serum increased significantly (p < 0.05) with supplementation of 100 mg/kg cerium oxide to laying hen diets. It was also observed that serum superoxide dismutase (SOD) activity and malondialdehyde (MDA) concentration decreased significantly with supplementation of cerium oxide in diets. Inclusion of cerium oxide resulted in a significant reduction in thiobarbituric acid reactive substance (TBARS) values in egg yolk in this study. It can be concluded that the addition of cerium oxide had positive effects on egg production, feed conversion ratio and egg shelf life. Based on the results of this study, it could be advised to supplement laying hens feed with cerium oxide as feed additives.

Nanoceria inhibit the development and promote the regression of pathologic retinal neovascularization in the Vldlr knockout mouse.

Many neurodegenerative diseases are known to occur and progress because of oxidative stress, the presence of reactive oxygen species (ROS) in excess of the cellular defensive capabilities. Age related macular degeneration (AMD), diabetic retinopathy (DR) and inherited retinal degeneration share oxidative stress as a common node upstream of the blinding effects of these diseases. Knockout of the Vldlr gene results in a mouse that develops intraretinal and subretinal neovascular lesions within the first month of age and is an excellent model for a form of AMD called retinal angiomatous proliferation (RAP). Cerium oxide nanoparticles (nanoceria) catalytically scavenge ROS by mimicking the activities of superoxide dismutase and catalase. A single intravitreal injection of nanoceria into the Vldlr-/- eye was shown to inhibit: the rise in ROS in the Vldlr-/- retina, increases in vascular endothelial growth factor (VEGF) in the photoreceptor layer, and the formation of intraretinal and subretinal neovascular lesions. Of more therapeutic interest, injection of nanoceria into older mice (postnatal day 28) resulted in the regression of existing vascular lesions indicating that the pathologic neovessels require the continual production of excessive ROS. Our data demonstrate the unique ability of nanoceria to prevent downstream effects of oxidative stress in vivo and support their therapeutic potential for treatment of neurodegenerative diseases such as AMD and DR.

[Lanthanides and microanalysis. Effects of oral administration of two lanthanides: ultrastructural and microanalytical study]. / Lanthanides et microanalyse. Effets de l'administration orale de deux lanthanides :etude ultrastructurale et microanalytique.

The subcellular localization of cerium and lanthanum in the intestinal mucosa was studied after oral administration of cerium chloride or lanthanum chloride or lanthanum chloride followed 30 minutes after of cerium chloride to young adults Wistar rats. Two methods of observation and microanalysis were used. The transmission electron microscopy revealed the presence of dense electron granulations in the lysosmes of the duodenum enterocyte, when these elements were administrated simultaneously. The ion mass microanalysis permits to detect the presence of La and Ce as bright points outlining the intestinal villi. These points correspond to the lysosomes containing the granulations previously described. These granulations are formed by the cerium and the lanthanum associated to the phosphor and forming probably insoluble salts of Ce/La phosphate.

Ce-TZP/Al2O3 nanocomposite as a bearing material in total joint replacement.

The objectives of this study were to investigate the biocompatibility, phase stability, and wear properties of a newly developed Ce-TZP/Al(2)O(3) nanocomposite, as compared to conventional ceramics, and to determine whether the new composite could be used as a bearing material in total joint prostheses. In tests of mechanical properties, this composite showed significantly higher toughness than conventional Y-TZP. For biocompatibility tests, cylindrical specimens of both the Ce-TZP/Al(2)O(3) nanocomposite and monolithic alumina were implanted into the paraspinal muscles of male Wistar rats. The tissue reactions were almost the same, and at 24 weeks after implantation, thin fibrous capsules with almost no inflammation were observed around both of them. There were no significant differences in membrane thickness between the two ceramics. After hydrothermal treatment in 121 degrees C vapor for 18 h, the new composite showed complete resistance to aging degradation, whereas Y-TZP showed a phase transformation of 25.3 vol% (initial 0.4%) to the monoclinic form. According to the results of pin-on-disk tests, the wear rates of Ce-TZP/Al(2)O(3) nanocomposite and alumina were 0.55 +/- 0.04 x 10(-7) and 2.12 +/- 0.37 x 10(-7)mm(3)/Nm, respectively. The results of this study suggest that the Ce-TZP/Al(2)O(3) nanocomposite is a promising alternative ceramic component for total joint replacement.

[The combined modulating effects of cerium nitrate with certain Chinese traditional drugs on altered cell-mediated immunities in scald mice].

Altered cell-mediated immunities (CMI) is one of the important causes of increased susceptibility to infection and, high mortality of burned patients. This paper presents the experimental work on mice with scald injury to restore their altered CMI by local application of cerium nitrate (CE) or systemic administration of Astragalus membranaceus (AM) or Lonicera japonica Thunb (LJT), as well as combination use of these drugs. The proliferative response to Con A and the ability of IL-2 production of murine spleen cells and the delayed hypersensitivity test using DNFB as sensitizer were chosen as the parameters of CMI. Results showed that CMI of untreated scald mice was suppressed to 50-60% of normal control 11 days following scald injury. While either CE used locally or AM or LJT given by oral with different dosages might bring up the depressed CMI to various degrees, near the normal level and some even above normal. When CE was used accompanied with AM or LJT, their effects on restoration of CMI were significantly better than that when any single drug was administered alone.