Lucrative antioxidant effect of metformin against cyclophosphamide induced nephrotoxicity

Cyclophosphamide is anticancer drug with a well-Known nephrotoxicity. This work was applied to study the lucrative antioxidant influence of metformin as co-therapy on the nephrotoxicity induced by cyclophosphamide in the treatment of different cancer diseases. Four groups of male Sprague Dawley rats were used; Control group (C) received single I.P. injection of 0.2 ml saline, Metformin (MET) group received daily gavage of 200 mg/kg metformin for two weeks, Cyclophosphamide (CP) group received single I.P. injection of 200 mg/kg CP, Protector group (CP.MET) received daily gavage of 200 mg/kg metformin for two weeks and single I.P. injection of 200 mg/kg CP at day 7. By day 14 rats were euthanized. Samples were collected from kidney tissues and blood for kidney function evaluation, histopathological and assessment of oxidative stress markers. The results disclosed that CP yields many functional and structural damage to the kidney, worsened oxidative stress markers and kidney function indicators. The protector group displayed better kidney tissue morphology, acceptable kidney function indicators as well as satisfactory oxidative stress markers.In assumption, metformin could be combined with CP owing to its lucrative effect counter to CP persuaded nephrotoxicity.     

Effects of anti-protozoal drugs and histopathological studies on trypanosome species

The trypanosomostatic and trypanosomicidal effects of four anti-protozoal drugs, namely halofantrine hydrochloride, chloroquine phosphate, benzoylmetronidazole and pyrimethamine, on species of trypanosomes, viz. Trypanosoma brucei brucei (MBOS/NG/94/NITR) Bassa strain, T. congolense (MBOS/NG/93/NVRI) Zaria strain and T. brucei gambiense (MHOM/NG/92/NITR) Abraka strain, were investigated. In vitro and in vivo studies on these drugs vis-a-vis the parasites were carried out. The histopathological changes in organs and tissues of experimentally infected rats were also studied. Results from the in vitro studies indicated that halofantrine hydrochloride, chloroquine phosphate, benzoylmetronidazole and pyrimethamine appeared to be effective trypanosomicidal agents against T. brucei brucei (Bassa strain), T. congolense (Zaria strain) and T. brucei gambiense (Abraka strain). The in vivo studies showed that these drugs were sub-curative by prolonging the survival period of the trypanosome-infected rats, but not necessarily curing the infection. Histopathological findings indicated inflammatory reactions characterised by infiltration to variable degrees in the majority of tissues, mostly in the lungs and liver. The most consistent lesions were interstitial pneumonia, multifocal necrosis and oedema. Pathological findings showed the T. brucei brucei and T. brucei gambiense strains studied to be both intravascular and extravascular parasites. These results suggest that halofantrine hydrochloride, chloroquine phosphate, benzoylmetronidazole and pyrimethamine could be used as supportive, suppressive and/or synergistic/additive drugs in the treatment of African trypanosomiasis. Their effects on species of trypanosomes have been studied and are reported for the first time.     

Acquisition of selenium tolerance by a selenium non-accumulating Astragalus species via selection

Selection of cultured cells of the selenium sensitive and non-accumulating Astragalus cicer for tolerance to stepwise increasing concentrations of selenite in the medium lead to a variant able to grow at 75 microM selenite. The Se-tolerant culture synthesized a selenocysteine methyltransferase immunologically related but not identical to that of the accumulating A. bisulcatus species and produced Se-methyl-selenocysteine in vivo. Re-cultivation in selenium-free medium lead to breakdown of tolerance and the disappearance of the methyltransferase from cellular proteins. The results prove that the non-accumulating species A. cicer has the cryptic capacity for synthesis of a selenocysteine methyltransferase and also demonstrate that synthesis of the organoselenium compounds in Se-accumulating plants are contributing to selenium tolerance.     

Uptake and distribution of selenium in different fern species

There has been an interest in using hyperaccumulating plants for the removal of heavy metals and metalloids. High selenium (Se) concentrations in the environment are detrimental to animals, humans, and sustainable agriculture, yet selenium is also an essential nutrient for humans. This experiment was conducted to screen fern plants for their potential to accumulate selenium. Eleven fern species, Pteris vittata, P. quadriaurita, P. dentata, P. ensiformis, P. cretica, Dryopteris erythrosora, Didymochlaena truncatula, Adiantum hispidulum, Actiniopteris radiata, Davallia griffithiana, and Cyrtomium fulcatum, were grown under hydroponic conditions for one week at 20 mg L(-1) selenate or selenite. Root Se concentrations reached 245-731 and 516-1082 mg kg(-1) when treated with selenate and selenite, respectively. The corresponding numbers in the fronds were 153-745 and 74-1,028 mg kg(-1) with no visible toxicity symptoms. Only three fern species were able to accumulate more Se in the fronds than the roots, which were D. griffithiana when treated with selenate, P. vittata when treated with selenite, and A. radiata regardless of the forms of Se. A. radiata was the best species overall for Se accumulation. More research is needed to further determine the potential of the fern species identified in this study for phytoremediation of the Se contaminated soils and water.     

Reduction of selenium oxyanions by unicellular,polymorphic and filamentous fungi: Cellular location of reduced selenium and implications for tolerance

Summary The ability of several filamentous, polymorphic and unicellular fungi to reduce selenite to elemental selenium on solid medium was examined.Fusarium sp. andTrichoderma reeii were the only filamentous fungi, of those tested, which reduced selenite to elemental selenium on Czapek-Dox agar resulting in a red colouration of colonies. Other organisms (Aspergillus niger, Coriolus versicolor, Mucor SK, andRhizopus arrhizus) were able to reduce selenite only on malt extract agar. Several fungi were able to grow in the presence of sodium selenite but were apparently unable to reduce selenite to elemental selenium, indicating that other mechanisms of selenite tolerance were employed, such as reduced uptake and/or biomethylation to less toxic, volatile derivatives. Sodium selenate was more toxic toFusarium sp. than selenite, and the toxicity of both oxyanions was increased in sulphur-free medium, with this effect being more marked for selenate. Scanning electron microscopy ofAspergillus funiculosus andFusarium sp. incubated with sodium selenite showed the presence of needle-like crystals of elemental selenium on the surfaces of hyphae and conidia, while transmission electron microscopy ofA. funiculosus revealed the deposition of electron-dense granules in vacuoles of selenite-treated fungi. Several yeasts were able to grow on MYGP agar containing sodium selenate or sodium selenite at millimolar concentrations. Sone, notablyRhodotorula rubra andCandida lipolytica, and the polymorphic fungusAureobasidium pullulans were also effective at reducing selenite to elemental selenium, resulting in red-coloured colonies.Schizosaccharomyces pombe was able to grow at selenite concentrations up to 5 mmol L^–1 without any evidence of reduction, again indicating the operation of other tolerance mechanisms.     

Soil boron and selenium removal by three plant species

High concentrations of boron (B) and selenium (Se) naturally found in the environment are detrimental to sustainable agriculture in the western USA. Greenhouse pot experiments were conducted to study B and Se uptake in three different plant species; Brassica juncea (L.) Czern (wild brown mustard), Festuca arundinacea Schreb. L. (tall fescue), and Brassica napus (canola) were grown in soil containing naturally occurring concentrations of 3.00 mg extractable B kg^–1 and 1.17 mg total Se kg^–1 soil. During the growing season, four intermediate harvests were performed on wild mustard and tall fescue. Final harvest I consisted of harvesting wild mustard, canola, and clipping tall fescue. Final harvest II consisted of harvesting wild mustard, which had been planted in soil in which wild mustard was previously grown, and harvesting previously clipped tall fescue. The greatest total amount of above ground biomass and below surface biomass was produced by tall fescue. Plants were separated into shoots and roots, weighted, and plant tissues were analyzed for total B and Se. The highest concentrations of tissue B were recovered in shoots of wild mustard and canola at final harvest I, while roots from tall fescue contained the highest concentrations of B irrespective of the harvest. Tissue Se concentrations were similar in all plants species. Soils were analyzed for residual B and Se. Extractable soil B concentrations at harvest times were lowered no less than 32% and total Se no less than 24% for all three species. The planting of wild mustard, canola, or tall fescue can reduce water-extractable B and total Se in the soil.     

Evaluation of comparative effect of pre‐ and posttreatment of selenium on mercury‐induced oxidative stress,histological alterations,and metallothionein mRNA expression in rats

To evaluate the effect of pre‐ or posttreatment of selenium (6 μmol/kg b.w., single intraperitoneal injection) in mercury intoxication, rats were exposed to mercury (12 μmol/kg b.w., single intraperitoneal injection). Exposure to mercury resulted in induced oxidative stress in liver, kidney, and brain tissues. Marked changes in serum biochemical parameters together with alterations in histopathology and an induction in metallothionein‐I and metallothionein‐II mRNA expression in the liver and kidney were observed. Pretreatment with selenium to mercury‐exposed animals had protective effect on the liver, whereas posttreatment had partial protection on restoration of altered oxidative stress parameters. In the kidney, pretreatment with selenium showed partial protection on restoration of altered biochemical parameters, whereas no protection was observed in posttreatment. The pretreatment with selenium resulted in restoration of mercury‐induced metallothionein‐I and metallothionein‐II mRNA expression, which was completely restored in the liver whereas partial restoration was observed in the kidney. Posttreatment with selenium resulted in further induction in metallothionein‐I and metallothionein‐II mRNA expression in the liver and kidney. In the brain, selenium showed partial protection on alerted biochemical parameters. Results indicate that pretreatment with selenium is beneficial in comparison to posttreatment in mercury intoxication. Thus, dietary intake of selenium within safe limit may, therefore, enable us in combating any foreseen effects due to mercury exposure. © 2010 Wiley Periodicals, Inc. J Biochem Mol Toxicol 24:123–135, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jbt.20320     

Metabolism of selenomethionine in selenium accumulator and non-accumulator astragalus species

The metabolism of selenomethionine in Astragalus crotalariae (a selenium-accumulating species) differs from that in Astragalus lentiginosus (a non-accumulator). After the administration of [⁷⁵Se]selenomethionine and [Me-¹⁴C]selenomethionine to excised leaves of A. crotalariae, Se-methylselenomethionine, Se-methylselenocysteine, and selenohomocystine were identified as the soluble components. A. lentiginosus formed mainly Se-methylselenomethionine, and a seleno peptide all of whose constituent amino acids have not been identified.When [³⁵S]methionine was administered to A. crotalariae a small amount was converted to S-methylmethionine but most was recovered as methionine. Homocrystine and S-methylcysteine were not formed in detectable amounts.     

Cellular reactions to sedimentation and temperature stress in the Caribbean coral Montastraea cavernosa

We present evidence of cellular responses to increased sedimentation and temperature in Montastraea cavernosa collected off Broward County, Florida. We sampled corals from six different sites approximately, 500-1000 m off shore, 10-15m depth. Six samples were collected from four sites adjacent to areas of underwater marine dredging (project sites), while the remaining two samples were obtained far away from the influence of the marine dredging (control sites). SSTs around collection time ranged 0.6-0.9 degrees C over the 40-year monthly mean. All specimens collected at project sites exhibited histopathological evidence of mild to moderate sedimentation stress including changes in size and number of mucocytes in epidermis and gastrodermis, attenuation of the epidermal and gastrodermal tissues, presence of cellular debris, and changes in number of zooxanthellae. These findings corroborate results of laboratory-based, sand-application experiments. In addition to the above-noted changes, one specimen exhibited multiple lesions consisting of unusual gastrodermal detachment with infiltration of amoebocytes into the adjacent mesoglea. Tissues surrounding detachment injuries exhibited marked to severe cellular changes. Accumulations of amoebocytes at lesion sites are seldom observed in wild corals. This response may be part of an organized reaction to injury and infection, as has been documented in sea anemones and gorgonians; however, further research is needed on the nature and role(s) of the scleractinian amoebocytes.     

Prophylactic effect of vitamin E against hepatotoxicity,nephrotoxicity, haematological indices and histopathology induced by diazinon insecticide in mice

Considering that the involvement of reactive oxygen species(ROS)has been implicated in the toxicity of various pesticides,this study was designed to study the ameliorative effect of Vitamin E(100 mg/kg body weight)on mice(25-30 mg)treated with diazinon(32.5 or 16.25 mg/kg body weight)organophosphate insecticide for 14 days.Subchronic DZN exposure and the protective effects of vitamins E(vitE)were evaluated for their effects on haematological indices,the enzymes concerning liver damage [plasma alanine aminot...     

Accumulation and volatilization of different chemical species of selenium by plants

Selenium (Se) removal from polluted waters and soils is especially complicated and highly expensive. Phytoremediation has been suggested as a low-cost, efficient technology for Se removal. Plants remove Se by uptake and accumulation in their tissues, and by volatilization into the atmosphere as a harmless gas. Unraveling the mechanisms of Se uptake and volatilization in plants may lead to ways of increasing the efficiency of the phytoremediation process. The objectives of this study were: (i) to determine the effect of different Se forms in the root substrate on the capacity of some plant species to take up and volatilize Se; (ii) to determine the chemical species of Se in different plant parts after the plants were supplied with various forms of Se; and (iii) to determine the influence of increasing sulfate levels on plant uptake, translocation, and volatilization of different Se species. Plants of broccoli (Brassica oleracea var. botrytis L.), Indian mustard (Brassica juncea L.), sugarbeet (Beta vulgaris L.) and rice (Oryza sativa L.) were grown hydroponically in growth chambers and treated for 1 week with 20 μM Se as Na₂SeO₄, Na₂SeO₃ or L-selenomethionine (SeMeth) and increasing sulfate levels. The data show that shoots of SeO₄-supplied plants accumulated the greatest amount of Se, followed by those supplied with SeMeth then SeO₃. In roots, the highest Se concentrations were attained when SeMeth was supplied, followed by SeO₃, then SeO₄. The rate of Se volatilization by plants followed the same pattern as that of Se accumulation in roots, but the differences were greater. Speciation analysis (X-ray absorption spectroscopy) showed that most of the Se taken up by SeO₄-supplied plants remained unchanged, whereas plants supplied with SeO₃ or SeMeth contained only SeMeth-like species. Increasing the sulfate level from 0.25 mM to 10 mM inhibited SeO₃ and SeMeth uptake by 33% and 15–25%, respectively, as compared to an inhibition of 90% of SeO₄ uptake. Similar results were observed with regard to sulfate effects on volatilization. We conclude that reduction from SeO₄ to SeO₃ appears to be a rate-limiting step in the production of volatile Se compounds by plants. Inhibitory effects of sulfate on the uptake and volatilization of Se may be reduced substantially if Se is supplied as, or converted to, SeO₃ and/or SeMeth rather than SeO₄. Received: 27 February 1998 / Accepted: 30 March 1998     

Exclusion of selenium from proteins of selenium-tolerant astragalus species

Protein fractions from three selenium-tolerant and three selenium-sensitive Astragalus species, grown in the presence of [⁷⁵Se]selenate, were analyzed for their selenium content. Though tolerant species are known to accumulate considerably more selenium than do sensitive plants, protein fractions from the three selenium accumulators were found to contain significantly less selenium (0.46 to 0.57 picomoles selenium per milligram protein) than did protein fractions from the three nonaccumulators (4.17 to 5.02 picomoles selenium per milligram protein). Under similar conditions, seedlings of Vigna radiata (L.) Wilczek had taken up selenium (6.31 picomoles selenium per milligram protein) at levels comparable to those observed in the proteins of the nonaccumulator Astragali. These results establish that the ability to tolerate and to circumvent the toxic effects of selenium, characteristic of the accumulator species of Astragalus, is associated with a reduced incorporation of this element into protein.     

Loss of selenium in drying and storage of agronomic plant species

Summary In two experiments with Se⁷⁵, loss of selenium from agricultural species was noted during both drying and storage. The loss of selenium during drying was to some extent overshadowed by the influence of self-absorption caused by the water in the fresh material. The results showed that even plant material of non-indicator plantslose volatile selenium at drying temperatures of 60°C or higher, and in some cases even at temperatures below 60°C. The results also showed that storage as briquettes gives the lowest storage loss of selenium.     

Prophylactic effect of vitamin E against hepatotoxicity,nephrotoxicity, haematological indices and histopathology induced by diazinon insecticide in mice

Considering that the involvement of reactive oxygen species （ROS） has been implicated in the toxicity of various pesticides, this study was designed to study the ameliorative effect of Vitamin E （100 mg/kg body weight） on mice （25 -30 mg） treated with diazinon （32.5 or 16.25 mg/kg body weight） organophosphate insecticide for 14 days. Subehronic DZN exposure and the protective effects of vitamins E （vitE） were evaluated for their effects on haematological indices, the enzymes concerning liver damage [plasma alanine aminotransferase （ ALT）, aspartate aminotaransferase （ AST）, alkaline phosphatise （ ALP）, and some parameters of kidney function （urea and creatinine） in mice. Additionally, the histopathological changes in liver and kidney tissue were examined. The high dose of diazinon （DZNH） decreased the body weight significantly at the end of experiment. Additionally, the liver and kidney were examines for histopathological changes. The high dose of diazinon decreased body weight significandy. Moreover, there was a statistically significant decrease in haemoglobin （Hb）, red blood cell （RBC） and hematocrit （Hct） in diazinon-treated mice compared to controls. This decrease was partially remedied in the diazinon-treated group that also received vitE. Damage in the liver and kidney tissues was also evident as elevated plasma ALT, AST, ALP, urea and creatinine. VitE partially counteracts the toxic effect of DZN and repairs tissue damage in the liver and kidney, especially when supplemented to 1/4 LD50 intoxicated animals. Histopathological changes in liver and kidney were observed only in 32.5 mg/kg DZN given group. These results suggest that the effects of DZN are dose dependent. No pathological findings were observed in vitE ＋ DZNtreated groups. According to the present study, we conclude that vitE ean reduce the detrimental impacts of diazinon on haematological indicies, as well as liver and kidney function [ Current Zoology 55 （3） ： 219 - 226, 2009].     

Cellular and free lipopolysaccharides of some species of Neisseria.

Cultures of eight non-pathogenic species of Neisseria grown in simple defined media released lipopolysaccharide (free lipopolysaccharide) by a process distinct from cellular autolysis. Analyses of the pure cellular and free lipopolysaccharides obtained from six species of Neisseria revealed that they were remarkably similar and were devoid of detectable O-antigen side chains. Three distinct types of core-oligosaccharides were demonstrated. Type I core-oligosaccharide was a branched structure of alpha-D-glucopyranosyl units (7 mol) terminated by a reducing end group of 3-deoxy-D-manno-octulosonic acid. Type II core-oligosaccharide contained D-glucose, 2-deoxy-2-amino-D-glucose, L-rhamnose, L-glycero-D-manno-heptose, 3-deoxy-D-manno-octulosonic acid, phosphate, and ethanolamine in a molar ratio of 3:2:1:1:1:1:1. Type III coreoligosaccharide was composed of D-glucose, L-glycero-D-manno-heptose, 3-deoxy-D-manno-octulosonic acid, and phosphate in a molar ratio of 3:3:1:1. Lipopolysaccharides of N. caviae and N. sicca contained type I core-oligosaccharides exclusively, while those of N. flava and N. perflava contained only type II core-oligosaccharide. Cellular lipopolysaccharide from N. cinerea contained core-oligosaccharides of types I and II in a ratio of 27:73, while the analogous preparation from N. flavescens contained core-oligosaccharide types II and III in a ratio of 21:4. Free lipopolysaccharides from these two organisms contained only one type of coreoligosaccharide. Lipid A components of all the lipopolysaccharide preparations were very similar being composed of about 25% by weight of dodecanoic acid, 3-hydroxy-dodecanoic acid, and 3-hydroxy-tetradecanoic acid.     

Comparative evaluation of selenium accumulation by allium species after foliar application of selenium nanoparticles,sodium selenite and sodium selenate

Accumulation and translocation intensity of selenium nanoparticles by natural selenium accumulators-perennial onions-is established and a decrease of these parameters is demonstrated in a sequence: Se⁺⁶ > Se⁰ > Se⁺⁴.     

Cellular localization of Nicastrin affects amyloid beta species production

The gamma-secretase complex, composed by presenilin, nicastrin, APH-1 and PEN-2, is involved in intramembranous proteolysis of membrane proteins, such as amyloid precursor protein or Notch. Cleavage occurs in multiple cellular compartments. Here, nicastrin mutants containing targeting signals to the endoplasmic reticulum, trans-Golgi network, lysosomes, or plasma membrane have been shown to yield active gamma-secretase complexes with different activities and specificities: wild-type and plasma membrane nicastrin complexes yielded the highest amounts of secreted amyloid-beta peptide (Abeta), predominantly Abeta40, whereas intracellular targeted mutants produced intracellular Abeta, with a comparatively higher amount of Abeta42. These results suggest that compartmental microenvironments play a role in gamma-secretase activity and specificity.     

A new species, Aphanomyces salsuginosus sp. nov., isolated from ice fish Salangichthys microdon

A species of Aphanomyces was isolated from the ice fish Salangichithys microdon living in brackish water in Japan. White cotton-like growth was found on the heads and fins of the fish. Hyphae penetrated into the dermal layers, subcutaneous tissues, muscular layers, and cartilaginous tissue of the mandible and maxilla; these hyphae were associated with cellular debris and lesions in host tissue. White fluffy colonies from subcultures of these growths were isolated on glucose–yeast agar plates with 0.5% sodium chloride (NaCl). These isolates consisted of delicate, slightly wavy, and moderately branched hyphae. Zoosporangia were isodiametric with the vegetative hyphae. Oogonia were abundant and approximately 21–33 μm in diameter, with irregular short papillae. Generally they were spherical or subspherical and only rarely pyriform. Individual oogonia usually contained a single oospore, which was spherical and 19–27 μm in diameter, with a large shiny vesicle. Antheridial branches, when present, were usually androgynous; however, they were sometimes monoclinous or diclinous. The optimal growth temperature of the isolates was 20°C, and cultures grew well at low salinity (0–0.5% NaCl). Phylogenic analysis based on the internal transcribed space 1-5.8S-ITS 2 of the ribosomal RNA gene indicates that these isolates will be an as-yet unidentified species of Aphanomyces.