Silver nanoparticles influenced rat serum metabolites and tissue morphology

Synthesis of Silver Nanoparticles from Aeromonas caviae for Antibacterial Activity and In Vivo Effects in Rats

Silver nanoparticles (AgNPs) have excellent antimicrobial properties, as they can inhibit multidrug-resistant (MDR) pathogens. Furthermore, bio-AgNPs have potential applications in medicine due to their low toxicity and high stability. Here, AgNPs were synthesized from the biomass of Aeromonas caviae isolated from a sediment sample and subsequently characterized. The UV-Vis spectra of AgNPs in aqueous medium peaked at 417 nm, matching their plasmon absorption. The X-ray diffraction analysis (XRD) pattern of AgNPs showed four peaks at 2θ values, corresponding to Ag diffraction faces. Absorption band peaks at 3420.16, 1635.54, and 1399.43 cm-1 were identified by Fourier-transform infrared spectroscopy (FTIR) analysis as belonging to functional groups of AgNP-associated biomolecules. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) showed that the nanoparticles are spherical and pseudospherical, with sizes of 15-25 nm. Agar well diffusion minimal inhibitory concentration (MIC) assays were used to assess the antibacterial activity of the nanoparticles against MDR pathogens. AgNPs exhibited antibacterial activity against MDR bacteria. Two groups of albino rats received intraperitoneal injections of AgNPs at 15 mg/kg or 30 mg/kg for 7 days. Blood, kidney, and liver samples were collected to investigate hematological, biochemical, and histopathological alterations. Administered AgNPs in rats fluctuated in liver and kidney function parameters. The ultrastructural impacts of AgNPs were more prominent at higher doses. The results proved the easy, fast, and efficient synthesis of AgNPs using A. caviae isolates and demonstrated the remarkable potential of these AgNPs as antibacterial agents. Nanotoxicological studies are required to identify the specific dose that balances optimal antibacterial activity with minimal toxicity to human health.

Toxicological evaluation of a nonlethal riot control combinational formulation upon dermal application using animal models

Numerous adverse effects on human health have been reported in epidemiological studies of oleoresin capsicum (OC) and other riot control agents (RCAs). Importantly, the daunting risk of such RCAs can be neutralized by optimizing the desired concentration of such agents for mob dispersal. Hence, a nonlethal riot control combinational formulation (NCF) was prepared for dispersing rioters without imparting fatal outcomes. However, for desired utilization of NCF, it is essential to recognize its extent of potential toxicity. Therefore, the current investigation evaluated the dermal toxicity of NCF using experimental animals in compliance with the OECD guidelines. Additionally, few essential metal ions were analyzed and found non -significantly different in the test rats as compared to control rats. Moreover, abnormal dermal morphology and lesions ultrastructural tissue defects were not noticed as evinced by different studies like ultrasonography, histology, and scanning electron microscopy (SEM) respectively. Further, Doppler ultrasonography exhibited non-significantly different blood flow velocity in both groups, whereas miles test demonstrated a significantly increased Evans blue concentration in test rats compared to the control rats, which might be due to an initial increase in blood flow via an instant action of the NCF at the cutaneous sensory nerve endings. However, our results demonstrated NCF can produce initial skin irritating and sensitizing effects in guinea pigs and rabbits without the antecedence of acute toxicity (≤2000 mg/kg) in Wistar rats.

Synthesis and in vivo evaluation of three fluid spray dried hybrid ciprofloxacin microparticles in Sprague Dawley rats

The aim of this study is to prepare and characterise mucoadhesive silica-coated silver nanoparticles loaded with ciprofloxacin (S-AgNPs-CSCFX), and investigate serum biochemical, haematological, and histopathological effects in Sprague Dawley rats upon oral administration. S-AgNPs-CSCFX microparticles were prepared using three fluid nozzle spray drying and characterised by scanning electron microscopy (SEM), X-ray dispersive spectrometry (EDX), transmission electron microscopy (TEM), Fourier transform infrared (FTIR), zeta potential and particles size measurements and X-ray powder diffraction (XRPD). Adult male Sprague Dawley rats were randomly divided between six-treated groups, including blank S-AgNPs and S-AgNPs-CSCFX (LD: Low dose; MD: Median Dose; HD: High Dose) and control group. Each group was treated daily to evaluate the effect of the prepared particles on the lipid profile, serum biochemical, hormonal level, haemogram, and vital organ histopathology. The results showed successful encapsulation of silver nanoparticles which resulted in spherical-shaped S-AgNPs-CSCFX with an average size of 1-5 μm and surface charge of 25.2 ± 5.52 mv. The in-vivo results showed that different doses of blank S-AgNPs and S-AgNPs-CSCFX had no significant toxic effects on the physiological, biochemical, and haematological parameters. There were no marked histopathological alterations in the vital organs of the treated rats with blank and loaded particles.

Hepatotoxic and Neurotoxic Potential of Iron Oxide Nanoparticles in Wistar Rats: a Biochemical and Ultrastructural Study

Iron oxide nanoparticles (IONPs) are increasingly being employed for in vivo biomedical nanotheranostic applications. The development of novel IONPs should be accompanied by careful scrutiny of their biocompatibility. Herein, we studied the effect of administration of three formulations of IONPs, based on their starting materials along with synthesizing methods, IONPs-chloride, IONPs-lactate, and IONPs-nitrate, on biochemical and ultrastructural aspects. Different techniques were utilized to assess the effect of different starting materials on the physical, morphological, chemical, surface area, magnetic, and particle size distribution accompanied with their surface charge properties. Their nanoscale sizes were below 40 nm and demonstrated surface up to 69m²/g, and increased magnetization of 71.273 emu/g. Moreover, we investigated the effects of an oral IONP administration (100 mg/kg/day) in rat for 14 days. The liver enzymatic functions were investigated. Liver and brain tissues were analyzed for oxidative stress. Finally, a transmission electron microscope (TEM) and inductively coupled plasma optical emission spectrometer (ICP-OES) were employed to investigate the ultrastructural alterations and to estimate content of iron in the selected tissues of IONP-exposed rats. This study showed that magnetite IONPs-chloride exhibited the safest toxicological profile and thus could be regarded as a promising nanotherapeutic candidate for brain or liver disorders.

Changes in Serum Physiological and Biochemical Parameters of Male Swiss Albino Mice After Oral Administration of Metal Oxide Nanoparticles (ZnO, CuO, and ZnO+CuO)

Zinc oxide (ZnO) and copper oxide (CuO) nanoparticles (NPs) are widely used in medicine and industrial fields. They have negative effects such as hematoxic, cytotoxic, and genotoxic on animals. This research aimed to investigate the blood physiological and biochemical responses induced by ZnO-NP and CuO-NP individually or in combination in male Swiss albino mice. For purpose, NPs were given to mice with 100 μl of water by oral gavage for 14 days. Three sublethal NP dose groups (1, 5, 25 mg/kg/day) and one control group (only received 100 μl of water) were used in the experiments and serum metabolite (glucose, total protein, total cholesterol, triglyceride, cortisol, blood urea nitrogen, immunoglobulin G, and M), ions (Na, K, Cl, Mg, and Ca), and enzyme (ALT, AST, ALP, and LDH) levels were measured. ZnO-, CuO-, and ZnO+CuO-NPs especially higher doses (5 and 25 mg/kg/day) decreased all serum metabolite (except blood urea nitrogen), ions, and ALP while these nanoparticles increased ALT, AST, LDH, and blood urea nitrogen. These increases/decreases in all serum parameters were generally higher in mice treated with the ZnO+CuO-NP mixture compared to the ZnO-NP and CuO-NP groups alone. The study shows that serum biochemistry profiles can be used as indicators to assess nanoparticle toxicity on lipid, protein, and energy metabolisms, immune and enzyme systems, ion regulation, and tissue functions.

Apoferritin and Apoferritin-Capped Metal Nanoparticles Inhibit Arginine Kinase of Trypanosoma brucei

The aim of this study was to explore the inhibitory potential of apoferritin or apoferritin-capped metal nanoparticles (silver, gold and platinum) against Trypanosomabrucei arginine kinase. The arginine kinase activity was determined in the presence and absence of apoferritin or apoferritin-capped metal nanoparticles. In addition, kinetic parameters and relative inhibition of enzyme activity were estimated. Apoferritin or apoferritin-capped metal nanoparticles’ interaction with arginine kinase of T. brucei led to a >70% reduction in the enzyme activity. Further analysis to determine kinetic parameters suggests a mixed inhibition by apoferritin or apoferritin-nanoparticles, with a decrease in V_max. Furthermore, the K_m of the enzyme increased for both ATP and L-arginine substrates. Meantime, the inhibition constant (K_i) values for the apoferritin and apoferritin-nanoparticle interaction were in the submicromolar concentration ranging between 0.062 to 0.168 nM and 0.001 to 0.057 nM, respectively, for both substrates (i.e., L-arginine and ATP). Further kinetic analyses are warranted to aid the development of these nanoparticles as selective therapeutics. Also, more studies are required to elucidate the binding properties of these nanoparticles to arginine kinase of T. brucei.

Role of Beetroot (Beta vulgaris) Juice on Chronic Nanotoxicity of Silver Nanoparticle-Induced Hepatotoxicity in Male Rats

Introduction

Nanoparticles are at the forefront of rapidly developing nanotechnology and have gained much attention for their application as an effective drug delivery system and as a mediated therapeutic agent for cancer. However, the cytotoxicity of nanoparticles is still relatively unknown and, therefore, additional study is required in order to elucidate the potential toxicity of these nanoparticles on cells.

Materials and Methods

Thus, the following work aimed to investigate the capability of Beta vulgaris (beetroot) water extract (BWE; 200 mg/kg) to protect hepatic tissue following silver nanoparticles (AgNPs; 80 mg/kg; >100 nm) intoxication in male rats.

Results

AgNPs-intoxication elevated the liver function markers – including serum transaminases and alkaline phosphatase activities – and decreased serum levels of albumin and total proteins, in addition to disturbing the oxidation homeostasis. This is evidenced by the increased lipid peroxidation, the depleted glutathione, and the suppressed activity of superoxide dismutase and catalase. In addition, an apoptotic reaction was observed following AgNPs treatment, as indicated by the up-regulation of p53 and down-regulating Bcl-2 expressions, examined by the immunohistochemistry method. Furthermore, AgNPs exhibited a marked elevation in liver DNA damage that was indicated by an increase in tail length, tail DNA% and tail movement. However, BWE eliminated the biochemical and histological alterations, reflecting its hepatoprotection effect in response to AgNPs.

Discussion

Collectively, the present data suggest that BWE could be used following AgNPs as a potential therapeutic intervention to minimize AgNPs-induced liver toxicity.

The oral administration of silver nanoparticles activates the kynurenine pathway in rat brain independently of oxidative stress

In this work, we determined whether oxidative stress contributed to the activation of the kynurenine pathway by AgNPs. Male Wistar rats weighing between 130 and 146 g were randomly assigned into six groups. Animals in the negative control group were orally administered distilled water while, the other treatment groups were respectively given AgNPs (25 and 50 mg/kg bw) alone or in combination with Trolox (100 mg/kg bw). Results showed that treatments with AgNPs significantly raised protein carbonyl level in rat liver, but the co-treatment with Trolox attenuated the elevation. Conversely, AgNPs raised the level of reduced glutathione (GSH) in rat plasma and tissues compared to the negative control. Further, oral exposure to AgNPs (50 mg/kg bw) significantly elevated rat plasma and brain kynurenine levels compared to the negative control. Meantime, the co-treatment with Trolox appreciably restored kynurenine level in rat plasma, but not in the rat brain. Taken together, findings indicate that the oral administration of AgNPs alone at the doses used in this study, might not have caused oxidative stress. However, the co-treatment with Trolox appears to potentiate oxidative stress in rats following exposure to AgNPs. Furthermore, data support that the activation of the kynurenine pathway in the rat brain by AgNPs might be independent of oxidative stress. The findings are new and contribute to deepen our understanding of the cellular interaction by nanoparticles.

Effect of long-term administration of Cinnamomum cassia silver nanoparticles on organs (kidneys and liver) of Sprague-Dawley rats

This study investigated the toxic effects of silver on the kidneys and livers of Sprague-Dawley rats after administering multiple doses of silver nanoparticles synthesized using extracts of Cinnamomum cassia (CcAgNPs). Twenty-four Sprague-Dawley rats (250 ± 20 g) were randomly assigned to four groups (A-D) of six animals per group and treated for 8 weeks. Group A was administered 200 mg/kg of Cinnamon Cassia extract (Cc), group B 5 mg/kg of CcAgNPs, group C 10 mg/kg of CcAgNPs, and group D normal saline. Body weight was measured weekly and fasting blood glucose was measured fortnightly. At the end of the experiment, animals were euthanized and organs (livers and kidneys) were fixed in neutral buffered formalin and processed for light microscopy (H&E). Body weight differences were significantly higher (P < 0.05) in the low-dose Cc group and the kidney to body weight ratio was not significant. Renal function analysis of proteins and ketones showed a significant increase in CcAgNP-treated rats (P < 0.05). Kidney and liver histology showed distortions in hepatocytes and sinusoidal linings with infiltrations especially in the higher dose groups. Kidney histology mirrored degenerative changes in glomerular and Bowman's capsules with bfirillary mesangial interstitium. CcAgNPs impairs renal and hepatic morphology and function after a long period of administration. 

Cerium Oxide Nanoparticles in Lung Acutely Induce Oxidative Stress, Inflammation, and DNA Damage in Various Organs of Mice

CeO₂ nanoparticles (CeO₂ NPs) which are used as a diesel fuel additive are emitted in the particulate phase in the exhaust, posing a health concern. However, limited information exists regarding the in vivo acute toxicity of CeO₂ NPs on multiple organs. Presently, we investigated the acute (24 h) effects of intratracheally instilled CeO₂ NPs in mice (0.5 mg/kg) on oxidative stress, inflammation, and DNA damage in major organs including lung, heart, liver, kidneys, spleen, and brain. Lipid peroxidation measured by malondialdehyde production was increased in the lungs only, and reactive oxygen species were increased in the lung, heart, kidney, and brain. Superoxide dismutase activity was decreased in the lung, liver, and kidney, whereas glutathione increased in lung but it decreased in the kidney. Total nitric oxide was increased in the lung and spleen but it decreased in the heart. Tumour necrosis factor-α increased in all organs studied. Interleukin- (IL-) 6 increased in the lung, heart, liver, kidney, and spleen. IL-1β augmented in the lung, heart, kidney, and spleen. Moreover, CeO₂ NPs induced DNA damage, assessed by COMET assay, in all organs studied. Collectively, these findings indicate that pulmonary exposure to CeO₂ NPs causes oxidative stress, inflammation, and DNA damage in multiple organs.

Single-walled carbon nanotubes disturbed the immune and metabolic regulation function 13-weeks after a single intratracheal instillation

Due to their unique physicochemical properties, the potential health effects of single-walled carbon nanotubes (SWCNTs) have attracted continuous attention together with their extensive application. In this study, we aimed to identify local and systemic health effects following pulmonary persistence of SWCNTs. As expected, SWCNTs remained in the lung for 13 weeks after a single intratracheal instillation (50, 100, and 200μg/kg). In the lung, the total number of cells and the percentages of lymphocytes and neutrophils significantly increased at 200μg/kg compared to the control, and the Th1-polarized immune response was induced accompanying enhanced expression of tissue damage-related genes and increased release of chemokines. Additionally, SWCNTs enhanced the expression of antigen presentation-related proteins on the surface of antigen-presenting cells, however, maturation of dendritic cells was inhibited by their persistence. As compared to the control, a significant increase in the percentage of neutrophils and a remarkable decrease of BUN and potassium level were observed in the blood of mice treated with the highest dose. This was accompanied by the down-regulation of the expression of antigen presentation-related proteins on splenocytes. Moreover, protein and glucose metabolism were disturbed with an up-regulation of fatty acid β-oxidation. Taken together, we conclude that SWCNTs may induce adverse health effects by disturbing immune and metabolic regulation functions in the body. Therefore, careful application of SWCNTs is necessary for the enforcement of safety in nano-industries.