Cytoplasmic Damage Research Articles

Synthesis of gold nanoparticles using Ginkgo biloba leaf extract and its in vitro anticancer effects on nasopharyngeal carcinoma cells

Green synthesis of gold nanoparticles (AuNPs) using Ginkgo biloba leaf aqueous extract was optimized by response surface methodology to yield monodispersed, crystalline nanoparticles of 18 ± 4 nm diameter. Fourier transform infrared spectroscopy confirmed capping by flavonoids, terpenoids and polyphenols providing stability for over 6 months. The biosynthesized AuNPs exhibited promising in vitro dose and time-dependent antiproliferative effects against human nasopharyngeal carcinoma CNE1 cells with IC50 reducing from 65.7 to 39.2 μg/mL over 24–72 hrs. Distinct cytoplasmic damage was observed under microscope. Treatment with 50 μg/mL AuNPs for 48 hrs dramatically upregulated pro-apoptotic Bax, Caspase-3 and p53 by 8.7, 6.5 and 4.3 fold respectively while downregulating anti-apoptotic Bcl-2 by 11.2 fold, indicating apoptosis induction via mitochondrial intrinsic pathway. The green fabricated G. biloba AuNPs displayed preferential toxicity towards carcinoma cells compared to normal fibroblasts, indicating potential for targeted nasopharyngeal cancer therapy.

Mogroside V Alleviates Oocyte Meiotic Defects and Quality Deterioration in Benzo(a)pyrene-Exposed Mice.

Accumulating evidence has demonstrated that benzo(a)pyrene (BaP) exposure adversely affects female reproduction, especially oocyte meiotic maturation and subsequent embryo development. Although we previously found that mogroside V (MV), a major bioactive component of S. grosvenorii, can protect oocytes from quality deterioration caused by certain stresses, whether MV can alleviate BaP exposure-mediated oocyte meiotic defects remains unknown. In this study, female mice were exposed to BaP and treated concomitantly with MV by gavage. We found that BaP exposure reduced the oocyte maturation rate and blastocyst formation rate, which was associated with increased abnormalities in spindle formation and chromosome alignment, reduced acetylated tubulin levels, damaged actin polymerization and reduced Juno levels, indicating that BaP exposure results in oocyte nucleic and cytoplasmic damage. Interestingly, MV treatment significantly alleviated all the BaP exposure-mediated defects mentioned above, indicating that MV can protect oocytes from BaP exposure-mediated nucleic and cytoplasmic damage. Additionally, BaP exposure increased intracellular ROS levels, meanwhile induced DNA damage and early apoptosis in oocytes, but MV treatment ameliorated these defective parameters, therefore it is possible that MV restored BaP-mediated oocyte defects by reducing oxidative stress. In summary, our findings demonstrate that MV might alleviate oocyte meiotic defects and quality deterioration in BaP-exposed mice.

Exposure to environmentally relevant oxytetracycline induced gut histopathological damages and microbiota alterations of Pelophylax nigromaculatus larvae

Antibiotics such as Oxytetracycline (OTC) is widely used around the world and it caused serious environmental issues in China, especially in Yangtze delta area. However, its effects on amphibian gut morphology and intestinal microbiota are still unclear. In this study, tadpoles of Pelophylax nigromaculatus was exposed to 0, 5, 90 and 450 μg/L OTC of environmentally relevant concentrations from Gosner (Gs) 26 to Gs 38. The results showed that severe histopathological injuries including cytoplasmic damage, cell arrangement disorganisation and structure deformation were observed in the gut of larvae in 90 and 450 μg/L OTC exposure groups. Moreover, Tunel assay also revealed higher apoptotic ratio in the intestine of tadpoles in 90 and 450 μg/L OTC treatment groups. Furthermore, the relative abundance of dominant phyla and genera of gut microbial community in OTC exposure groups was significantly different from that of control though the richness and species diversity did not show remarkable changes. We concluded that OTC may pose potential health risks to amphibian larvae through inducing gut histopathological injury and intestinal microbiota dysbiosis.

The rumen eukaryotome is a source of novel antimicrobial peptides with therapeutic potential

BackgroundThe rise of microbial antibiotic resistance is a leading threat to the health of the human population. As such, finding new approaches to tackle these microbes, including development of novel antibiotics is vital.ResultsIn this study, we mined a rumen eukaryotic metatranscriptomic library for novel Antimicrobial peptides (AMPs) using computational approaches and thereafter characterised the therapeutic potential of the AMPs. We identified a total of 208 potentially novel AMPs from the ruminal eukaryotome, and characterised one of those, namely Lubelisin. Lubelisin (GIVAWFWRLAR) is an α-helical peptide, 11 amino acid long with theoretical molecular weight of 1373.76 D. In the presence of Lubelisin, strains of methicillin-resistant Staphylococcus aureus (MRSA) USA300 and EMRSA-15 were killed within 30 min of exposure with ≥103 and 104 CFU/mL reduction in viable cells respectively. Cytotoxicity of Lubelisin against both human and sheep erythrocytes was low resulting in a therapeutic index of 0.43. Membrane permeabilisation assays using propidium iodide alongside transmission electron microscopy revealed that cytoplasmic membrane damage may contribute to the antimicrobial activities of Lubelisin.ConclusionsWe demonstrate that the rumen eukaryotome is a viable source for the discovery of antimicrobial molecules for the treatment of bacterial infections and further development of these may provide part of the potential solution to the ongoing problem of antimicrobial resistance. The role of these AMPs in the ecological warfare within the rumen is also currently unknown.

Deoxymikanolide adversely altered physiology and ultrastructure of Ralstonia solanacearum

Deoxymikanolide (DEO) was isolated from Mikania micrantha Bunge and identified as a novel antibacterial compound previously. However, the mode of antimicrobial mechanism of DEO was not clear but hypothesized to affect the morphology and physiology of Ralstonia solanacearum cells. In this study, we confirmed our hypothesis via transmission electron microscopy (TEM) observation and comprehensive physiological analyses, including electric conductivity, glycan and phosphorus metabolism, activities of antioxidant enzymes (catalase, peroxidase, and superoxide dismutase), intrabacterial reactive oxygen species (ROS), and malondialdehyde (MDA) levels. We found that glycan and phosphorus metabolism, electric conductivity, intracellular ROS and MDA levels of R. solanacearum cells were significantly increased, while the activities of three antioxidant enzymes were significantly inhibited by DEO treatment. Moreover, TEM analysis showed that DEO treatment led to an early-stage of cell shrinkage, intermediate-stages of cytoplasmic damage, and a final-stage of cell disruption. Altogether, our data presented here indicate that DEO could adversely affect the physiology and morphology of R. solanacearum cells and be treated as an alternative antibacterial treatment in the future.

IMPACT OF SORBITOL- INDUCED OSMOTIC STRESS ON SOME BIOCHEMICAL TRAITS OF POTATO IN VITRO

This study had as principal objective identification of osmotic-tolerant potato genotypes by using "in vitro" tissue culture and sorbitol as a stimulating agent, to induce water stress, which was added to the culture nutritive medium in different concentration (0,50, 110, 220, 330 and 440 mM). The starting point was represented by plantlets culture collection, belonging to eleven potato genotypes: Barcelona, Nectar, Alison, Jelly, Malice, Nazca, Toronto, Farida, Fabulla, Colomba and Spunta. Plantlets were multiplied between two internodes to obtain microcuttings (in sterile condition), which were inoculated on medium. Sorbitol-induced osmotic stress caused a significant reduction in the ascorbic acid, while the concentration of proline, H2O2 and solutes leakage increased compared with the control. Increased the proline content prevented lipid peroxidation, which played a pivotal role in the maintenance of membrane integrity under osmotic stress conditions. The extent of the cytoplasmic membrane damage depends on osmotic stress severity and the genotypic variation in the maintenance of membranes stability was highly associated with the ability of producing more amounts of osmoprotectants (proline) and the non-enzymic antioxidant ascorbic acid in response to osmotic stress level. The results showed that the genotypes Jelly, Nectar, Allison, Toronto, and Colomba are classified as highly osmotic stress tolerant genotypes, while the genotypes Nazca and Farida are classified as osmotic stress susceptible ones.

Quinine Improves the Fungicidal Effects of Antimicrobial Blue Light: Implications for the Treatment of Cutaneous Candidiasis.

Candida albicans is an opportunistic fungal pathogen of clinical importance and is the primary cause of fungal-associated wound infections, sepsis, or pneumonia in immunocompromised individuals. With the rise in antimicrobial resistance, it is becoming increasingly difficult to successfully treat fungal infections using traditional antifungals, signifying that alternative non-traditional approaches must be explored for their efficacy. We investigated the combination of antimicrobial blue light (aBL) and quinine hydrochloride (Q-HCL) for improved inactivation of C. albicans, in vitro and in vivo, relative to either monotherapy. In addition, we evaluated the safety of this combination therapy in vivo using the TUNEL assay. The combination of aBL (108 J/cm2 ) with Q-HCL (1 mg/mL) resulted in a significant improvement in the inactivation of C. albicans planktonic cells in vitro, where a 7.04 log10 colony forming units (CFU) reduction was achieved, compared with aBL alone that only inactivated 3.06 log10 CFU (P < 0.001) or Q-HCL alone which did not result in a loss of viability. aBL + Q-HCL was also effective at inactivating 48-hour biofilms, with an inactivation 1.73 log10 CFU at the dose of 108 J/cm2 aBL and 1 mg/mL Q-HCL, compared with only a 0.73 or 0.66 log10 CFU by aBL and Q-HCL alone, respectively (P < 0.001). Transmission electron microscopy revealed that aBL + Q-HCL induced morphological and ultrastructural changes consistent with cell wall and cytoplasmic damage. In addition, aBL + Q-HCL was effective at eliminating C. albicans within mouse abrasion wounds, with a 2.47 log10 relative luminescence unit (RLU) reduction at the dose of 324 J/cm2 aBL and 0.4 mg/cm2 Q-HCL, compared with a 1.44 log10 RLU reduction by aBL alone. Q-HCL or nystatin alone did not significantly reduce the RLU. The TUNEL assay revealed some apoptotic cells before and 24 hours following treatment with aBL + Q-HCL. The combination of aBL + Q-HCL was effective at eliminating C. albicans both in vitro and in vivo. A comprehensive assessment of toxicity (cytotoxicity and genotoxicity) is required to fully determine the safety of aBL + Q-HCL therapy at different doses. In conclusion, the combination of aBL and Q-HCL may be a viable option for the treatment of cutaneous candidiasis. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

Pulmonary and hepatic effects after low dose exposure to nanosilver: Early and long-lasting histological and ultrastructural alterations in rat.

Although environmental airborne silver nanoparticles (AgNPs) levels in occupational and environmental settings are harmful to humans, the precise toxic effects at the portal entry of exposure and after translocation to distant organs are still to be deeply clarified. To this aim, the present study assessed histopathological and ultrastructural alterations (by means of H&E and TEM, respectively) in rat lung and liver, 7 and 28 days after a single intratracheal instillation (i.t) of a low AgNP dose (50 microg/rat), compared to those induced by an equivalent dose of ionic silver (7 microg AgNO3/rat). Lung parenchyma injury was observed acutely after either AgNPs or AgNO3, with the latter compound causing more pronounced effects. Specifically, alveolar collapse accompanied by inflammatory alterations and parenchymal fibrosis were revealed. These effects lasted until the 28th day, a partial pulmonary structure recovery occurred, nevertheless a persistence of slight inflammatory/fibrotic response and apoptotic phenomena were still detected after AgNPs and AgNO3, respectively. Concerning the liver, a diffuse hepatocyte injury was observed, characterized by cytoplasmic damage and dilation of sinusoids, engulfed by degraded material, paralleled by inflammation onset. These effects already detectable at day 7, persisting at the 28th day with some attenuations, were more marked after AgNO3 compared to AgNPs, with the latter able to induce a ductular reaction. Altogether the present findings indicate toxic effects induced by AgNPs both at the portal entry (i.e. lung) and distant tissue (i.e. liver), although the overall pulmonary damage were more striking compared to the hepatic outcomes.

VISUALIZATION OF THE DNA REPAIR PROCESS IN MAMMALIAN CELLS TRANSFECTED WITH EGFP-EXPRESSING PLASMID DNA AFTER EXPOSURE TO X-RAYS IN VITRO.

To investigate the repair process of DNA damage induced by ionizing radiation in isolation from various types of cytoplasmic damage, we transfected X-irradiated enhanced green fluorescent protein (EGFP)-expressing plasmid DNA into non-irradiated mammalian cells using lipofectamine. The repair kinetics of the irradiated plasmids in the cells were visualized under microscopy as the EGFP fluorescence emitted by transfected cells. Using an agarose gel electrophoresis method, the yields of single- and double-strand breaks of the plasmids were also quantified. As positive control experiments, plasmid DNA with single- or double-strand breaks induced by a nicking or restriction enzyme were also transfected into the cells. The DNA repair rates for X-ray-irradiated plasmids were significantly lower than those of the enzymatically digested positive control samples. These results indicate that X-rays could induce less repairable damage than that induced by enzymes.

METH-Induced Neurotoxicity Is Alleviated by Lactulose Pretreatment Through Suppressing Oxidative Stress and Neuroinflammation in Rat Striatum.

Abuse of methamphetamine (METH) results in neurological and psychiatric abnormalities. Lactulose is a poorly absorbed derivative of lactose and can effectively alleviate METH-induced neurotoxicity in rats. The present study was designed to investigate the effects of lactulose on METH-induced neurotoxicity. Rats received METH (15 mg/kg, 8 intraperitoneal injections, 12-h interval) or saline and received lactulose (5.3 g/kg, oral gavage, 12-h interval) or vehicle 2 days prior to the METH administration. Reactive oxygen species (ROS) and malondialdehyde (MDA) were measured. Protein levels of toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), tumor necrosis factor receptor associated factor 6 (TRAF6), nuclear factor κB (NFκB), interleukin (IL)-1β, IL-6, TNF-α, cleaved caspase 3, and poly(ADP-ribose) polymerase-1 (PARP-1) were determined by western blotting. mRNA expressions of nuclear factor erythroid 2-relatted factor-2 (Nrf2), p62, and heme oxygenase-1 (HO-1) were assessed by RT-qPCR. The lactulose pretreatment decreased METH-induced cytoplasmic damage in rat livers according to histopathological observation. Compared to the control group, overproduction of ROS and MDA were observed in rat striatums in the METH alone-treated group, while the lactulose pretreatment significantly attenuated the METH-induced up-regulation of oxidative stress. The lactulose pretreatment significantly repressed over-expressions of proteins of TLR4, MyD88, TRAF6, NFκB, IL-1β, IL-6, TNF-α, cleaved caspase 3, PARP-1. The lactulose pretreatment increased mRNA expressions of Nrf2, p62, and HO-1. These findings suggest that lactulose pretreatment can alleviate METH-induced neurotoxicity through suppressing neuroinflammation and oxidative stress, which might be attributed to the activation of the Nrf2/HO-1 axis.

Enhanced DNA double strand break repair triggered by microbeam irradiation induced cytoplasmic damage

Objective: Direct exposure of the nucleus to radiation, is the primary cause of various radiobiological effects. However, the cytoplasm is equally exposed to radiation during treatments that result in activation of intracellular response. Thus, the present study is aimed at investigating (1) whether cytoplasmic irradiation affects double-strand breaks (DSBs) repair when the cytoplasm (C) and nucleus (N) is irradiated sequentially, and (2) whether the cytoplasmic irradiation alone is sufficient to induce DNA DSBs in the nucleus. Materials and Methods: To distinguish the radiobiological effects between nuclear and cytoplasmic irradiation, all the experiments were conducted using the SPICE - National Institute of Radiological Sciences microbeam (SPICE) that can target precisely the N and/or C with desired number of 3.4 MeV protons. We examined the kinetics of DSB repair in WI-38 normal human fibroblast cells that were irradiated by microbeam targeted to the N, C, or N + C. Cells were fixed at various time points between 1 and 24 h postirradiation. Subsequently, they were immunostained with antibodies against γ-H2AX, a DSB marker, and imaged, to quantify the residual DSB in each nucleus. Results: Microbeam irradiation induced significant γ-H2AX, directly proportional to the number of protons delivered per N. In the C-targeted cells, γ-H2AX levels did not increase significantly, compared to controls, 1-h postirradiation. However, 4-h postirradiation, γ-H2AX levels were significantly increased in C-targeted cells, compared to nonirradiated controls, and the increase was proportional to the number of protons delivered. Cells irradiated with 500 protons per N, showed lowered residual γ-H2AX levels in N + C cells additionally irradiated with 500 or 1000 protons targeted to the C, 16 and 24 h postirradiation, respectively. Conclusion: Our results suggest that cytoplasmic damage triggers enhanced repair of DSBs that are induced on nucleus irradiation.

Cytoplasmic Irradiation Induces Metabolic Shift in Human Small Airway Epithelial Cells via Activation of Pim-1 Kinase.

The unique cellular and molecular consequences of cytoplasmic damage caused by ionizing radiation were studied using a precision microbeam irradiator. Our results indicated that targeted cytoplasmic irradiation induced metabolic shift from an oxidative to glycolytic phenotype in human small airway epithelial cells (SAE). At 24 h postirradiation, there was an increase in the mRNA expression level of key glycolytic enzymes as well as lactate secretion in SAE cells. Using RNA-sequencing analysis to compare genes that were responsive to cytoplasmic versus nuclear irradiation, we found a glycolysis related gene, Pim-1, was significantly upregulated only in cytoplasmic irradiated SAE cells. Inhibition of Pim-1 activity using the selective pharmaceutic inhibitor Smi-4a significantly reduced the level of lactate production and glucose uptake after cytoplasmic irradiation. In addition, Pim-1 also inhibited AMPK activity, which is a well-characterized negative regulator of glycolysis. Distinct from the glycolysis induced by cytoplasmic irradiation, targeted nuclear irradiation also induced a transient and minimal increase in glycolysis that correlated with increased expression of Hif-1α. In an effort to explore the underline mechanism, we found that inhibition of mitochondria fission using the cell-permeable inhibitor mdivi-1 suppressed the induction of Pim-1, thus confirming Pim-1 upregulation as a downstream effect of mitochondrial dysfunction. Our data show and, for the first time, that cytoplasmic irradiation mediate expression level of Pim-1, which lead to glycolytic shift in SAE cells. Additionally, since glycolysis is frequently linked to cancer cell metabolism, our findings further suggest a role of cytoplasmic damage in promoting neoplastic changes.

Effect of copper sulphate on the lung damage induced by chronic intermittent exposure to ozone

Ozone exposure could increase lung damage induced by airborne particulate matter. Particulate matter lung toxicity has been attributed to its metallic content. To evaluate the acute effect of intratracheal administration of copper sulfate (CuSO4) on rat lungs previously damaged by a chronic intermittent ozone exposure. Two-months-old male Sprague-Dawley rats were exposed to 0.5 ppm ozone four h per day, five days a week, during two months. CuSO4 was intratracheally instilled 20 h after ozone exposure. Controls breathed filtered air or were instilled with 0.9% NaCl or with CuSO4 or were only exposed to ozone. We evaluated lung histopathology. F2 isoprostanes were determined in plasma. Cell count, total proteins, γ glutamyl-transpeptidase (GGT) and alkaline phosphatases (AP) were determined in bronchoalveolar lavage fluid (BALF). Ozone increased total cell count, macrophages, proteins and AP in BALF (p < 0.05), and induced pulmonary neutrophil inflammation. CuSO4 plus air increased plasma F2 isoprostane levels and total cell count, neutrophils and proteins in BALF (p < 0.05). Histopathology showed foamy macrophages. Ozone plus CuSO4 exposed animals showed a neutrophil inflammatory lung response and an increase in total cell count, proteins, GGT and AP in BALF (p < 0.05). Foamy and pigmented alveolar macrophages were detected in all lungs of these animals (p < 0.001). Intratracheal instillation of a single dose of CuSO4 in rats previously subjected to a chronic and intermittent exposure to ozone induces a neutrophil pulmonary inflammatory response and cytoplasmic damage in macrophages.

Physiological and Molecular Responses to Excess Boron in Citrus macrophylla W.

This work provides insight into several mechanisms involved in boron (B) regulation pathway in response to high B conditions in Citrus. The study was carried out in Citrus macrophylla W. (Cm) seedlings cultured “in vitro” in media with 50 or 400 μM H3BO3 (control, Ct, and B-excess, +B, plants, respectively). Growth parameters, B concentration, leaf chlorophyll (Chl) concentration, the expression of the main putative genes involved in B transport and distribution, and leaf and root proline and malonaldehyde (MDA) concentrations, were assessed. Excess B led to high B concentration in +B plants (3.8- and 1.4-fold in leaves and roots, respectively) when compared with Ct ones. However, a minor effect was recorded in the plant (incipient visual symptoms, less than 27% reduction in root growth and 26% decrease in Chl b concentration). B toxicity down-regulated by half the expression level of putative B transporter genes NIP5 and PIP1. CmBOR1 gene was not repressed in +B plants and B accumulated in the shoots. High B level increased the transcripts of putative gene TIP5, involved in B transport across the tonoplast, by 3.3- and 2.4-fold in leaves and roots, respectively. The activity of V-PPiase proton pump, related with the electrochemical gradient in the vacuole, was also enhanced in +B organs. B toxicity up-regulated putative BOR4 gene (2.1- and 2.7-fold in roots and leaves, respectively), which codifies for an active efflux B transporter. Accordingly, B was located in +B plants preferently in an insoluble form on cell walls. Finally, excess B caused a significant rise in proline concentration (51% and 34% in roots and leaves, respectively), while the MDA level did not exceed 20%. In conclusion, Cm tolerance to a high B level is likely based on the synergism of several specific mechanisms against B toxicity, including: 1/ down-regulation of NIP5 and PIP1 boron transporters; 2/ activation of B efflux from cells due to the up-regulation of putative BOR4 gene; 3/ compartmentation of B in the vacuole through TIP5 transporter activation and the acidification of the organelle; 4/ insolubilisation of B and deposition in cell walls preventing from cytoplasm damage; and, 5/ induction of an efficient antioxidant system through proline accumulation.

Monoacylated Cellular Prion Proteins Reduce Amyloid-β-Induced Activation of Cytoplasmic Phospholipase A2 and Synapse Damage.

Alzheimer’s disease (AD) is a progressive neurodegenerative disease characterized by the accumulation of amyloid-β (Aβ) and the loss of synapses. Aggregation of the cellular prion protein (PrPC) by Aβ oligomers induced synapse damage in cultured neurons. PrPC is attached to membranes via a glycosylphosphatidylinositol (GPI) anchor, the composition of which affects protein targeting and cell signaling. Monoacylated PrPC incorporated into neurons bound “natural Aβ”, sequestering Aβ outside lipid rafts and preventing its accumulation at synapses. The presence of monoacylated PrPC reduced the Aβ-induced activation of cytoplasmic phospholipase A2 (cPLA2) and Aβ-induced synapse damage. This protective effect was stimulus specific, as treated neurons remained sensitive to α-synuclein, a protein associated with synapse damage in Parkinson’s disease. In synaptosomes, the aggregation of PrPC by Aβ oligomers triggered the formation of a signaling complex containing the cPLA2.a process, disrupted by monoacylated PrPC. We propose that monoacylated PrPC acts as a molecular sponge, binding Aβ oligomers at the neuronal perikarya without activating cPLA2 or triggering synapse damage.

Impact of Lycopene on Epididymal Androgen and Estrogen Receptors’ Expression in Polychlorinated Biphenyls–Exposed Rat

The aim of the study was to evaluate the androgen (AR) and estrogen receptors' (ER) expression in epididymis of polychlorinated biphenyls (PCBs)-exposed rats. The rats were assigned to groups. Group I controls were treated with corn oil 80 µL/d intraperitoneally (ip), group II were treated with 2 mg/kg/d of A1254 ip; and group III were treated with 2 mg/kg/d of A1254 ip along with simultaneous oral supplementation of 4 mg/kg/d lycopene . The treatment was given daily for 30 days. After 24 hours of treatment, the rats were killed, and the epididymal regions (caput, corpus, and cauda) were dissected out, weighed, and prepared to estimate the levels of sialic acid, glyceryl phosphoryl choline (GPC), hydrogen peroxide (H2O2), and lipid peroxidation (LPO). The messenger RNA (mRNA) expressions of AR, ERα, and ERβ were analyzed by reverse transcriptase-polymerase chain reaction, and ERα and ERβ protein expressions were analyzed by immunoblotting. The toxicity of PCBs was also confirmed by histology. There was a marked decrease in epididymal weight, sialic acid, and GPC levels, while oxidative stress markers H2O2 and LPO were increased in PCBs-treated rats. The mRNA and protein expression of AR, ERα, and ERβ were decreased in PCBs-treated groups, and the histology confirms the cytoplasmic damage in the regions of caput, corpus, and cauda in PCBs-treated rats. Simultaneous supplementation of lycopene to PCBs-exposed rats resulted in significant decrease in the oxidative stress markers as that of control, while the AR, ERα, and ERβ gene expressions were near to control. The results suggest that lycopene has ameliorative effect against PCBs-induced toxicity in epididymis.

Histopathological effects of anthrax lethal factor on rat liver

Bacillus anthracis, the causative agent of anthrax, has become an increasingly important scientific topic due to its potential role in bioterrorism. The lethal toxin (LT) of B. anthracis consists of lethal factor (LF) and a protective antigen (PA). This study investigated whether only lethal factor was efficient as a hepatotoxin in the absence of the PA. To achieve this aim, LF (100 µg/kg body weight, dissolved in sterile distilled water) or distilled water vehicle were intraperitoneally injected once into adult rats. At 24 h post-injection, the hosts were euthanized and their livers removed and tissue samples examined under light and electron microscopes. As a result of LF application, hepatic injury – including cytoplasmic and nuclear damage in hepatocytes, sinusoidal dilatation, and hepatocellular lysis – became apparent. Further, light microscopic analyses of liver sections from the LF-injected rats revealed ballooning degeneration and cytoplasmic loss within hepatocytes, as well as peri-sinusoidal inflammation. Additionally, an increase in the numbers of Kupffer cells was evident. Common vascular injuries were also found in the liver samples; these injuries caused hypoxia and pathological changes. In addition, some cytoplasmic and nuclear changes were detected within the liver ultrastructure. The results of these studies allow one to suggest that LF could be an effective toxicant alone and that PA might act in situ to modify the effect of this agent (or the reverse situation wherein LF modifies effects of PA) such that lethality results.

English

Aim: This study described the histopathological profile of the cerebellar cortex and liver of rats with carbon tetrachloride (CCl4)-induced liver damage. Methods: Male Wistar rats weighing about 250 g were divided into 2 groups (A and B). Group A (control) rats were treated with olive oil (OO) solution only while Group B rats were treated with carbon tetrachloride (CCl4) for 8 weeks. Thereafter, the cerebellum and liver of the rats were processed and stained with cresyl fast violet and H&amp;E, respectively, for histopathological examinations of the cerebellar cortex and liver. Result: Histopathological analysis shows cortical necrosis, uneven neuronal loss with varying range of vacuolations in the cerebellar cortices and moderate vascular congestion and extensive cytoplasmic damage on the hepatocytes of the CCl4 treated rats. Conclusion: There is of loss of hepatic function in the CCl4 treated rats. &nbsp; Key words: -Neurons, Neuropathology, Vacuolations, Necrosis, Neuronal loss.

English

In cirrhosis, some toxic substances accumulate in the brain and modify its functional integrity. In this study, we investigate the impacts of liver damage on the neuronal profile of the prefrontal cortex (PFC) in a rat model of hepatic damage induced with carbon tetrachloride (CCl4). This study also evaluated the possible role of liver dysfunction in the etiology of neurodegenerative characteristics associated with the PFC. Ten male Wistar rats weighing 120 to 190 g body weight were used for this study. The rats were divided into 2 groups (A and B) of 5 rats each. The rats in group A (control group) were treated with phosphate buffered saline (PBS) solution only while the rats in group B (treatment group) were treated with carbon tetrachloride (CCl4). The prefrontal cortices of the rats were excised from skulls of the rats, fixed in formol calcium, while the livers were excised from the abdomen of the rats and were fixed in formol saline for cytoarchitectural study using Cresyl fast violet and hematoxylin and eosin stains respectively. The main neuropathological findings observed in this study include cortical necrosis, uneven neuronal loss with varying range of vacuolations in the prefrontal cortices of the CCl4&nbsp;treated rats when compared with the PBS treated rats. It was observed that the administration of CCl4&nbsp;induces changes in hepatocellular morphology of the treated rats and these include moderate vascular congestion and extensive cytoplasmic damage in the hepatocytes. These results could be due to loss of hepatic functions. &nbsp; Key words:&nbsp;Liver damage, neuropathology, neurons, prefrontal cortex, rat.

Role of ABCC1 in protecting the heart against doxorubicin (DOX)‐induced oxidative stress

We investigated the role of multidrug resistance‐associated protein 1 (Mrp1), an ATP‐binding cassette transporter (ABCC1), in mouse heart following DOX‐induced oxidative stress. Wildtype (WT) and Mrp1−/− (KO) C57BL/6 littermates were administered a single dose of 20 mg/kg DOX or Saline (SAL) intravenously. Hearts were collected 72 h later, and ultrastructural damage measured by electron microscopy (EM) (n=6) and content of the glutathione conjugate of 4‐hydroxynonenal (GS‐HNE), a substrate of Mrp1, determined by LC‐MS (n=6–7). The mRNA of Nrf2 responsive genes, Nqo1, GPX1, GPX3, and GPX4 were quantitated by real time quantitative PCR (n=6). Morphometric analysis of EM data showed a trend (p = 0.063) for decreased cytoplasmic + mitochondrial damage in DOX‐treated KO mice vs WT, but increased (p = 0.031) nuclear injury in KO mice. In contrast, SAL induced more cytoplasmic damage in KO mice (p = 0.015). GS‐HNE (nmol/g heart tissue) of WT and KO SAL mice were similar, whereas DOX decreased (p &lt; 0.001) GS‐HNE in WT mice, but had no effect in KO mice. The basal level of GS‐HNE in naïve KO mice was lower (p = 0.013) than in naive WT mice (n=8). DOX increased mRNA of Nqo1 and GPX3 in hearts of WT and KO mice similarly, but had little influence on GPX1 and GPX4 mRNA. Nevertheless, in naïve mice, basal levels of Nqo1, GPX3, and GPX4 mRNA were lower in KO than in WT (p = 0.001, 0.011, 0.022, respectively). These data imply that the elevated GSH level in hearts of KO mice is able to protect against some forms of DOX‐induced injury, but not others. (CA139844)