scholarly journals Sex-, tissue-, and exposure duration-dependent effects of imidacloprid modulated by piperonyl butoxide and menadione in rats. Part I: oxidative and neurotoxic potentials

2014 ◽  
Vol 65 (4) ◽  
pp. 387-398 ◽  
Author(s):  
Mustafa Yardimci ◽  
Yusuf Sevgiler ◽  
Eyyup Rencuzogullari ◽  
Mehmet Arslan ◽  
Mehmet Buyukleyla ◽  
...  

Abstract Earlier research has evidenced the oxidative and neurotoxic potential of imidacloprid, a neonicotinoid insecticide, in different animal species. The primary aim of this study was to determine how metabolic modulators piperonyl butoxide and menadione affect imidacloprid’s adverse action in the liver and kidney of Sprague-Dawley rats of both sexes. The animals were exposed to imidacloprid alone (170 mg kg-1) or in combination with piperonyl butoxide (100 mg kg-1) or menadione (25 mg kg-1) for 12 and 24 h. Their liver and kidney homogenates were analysed spectrophotometrically for glutathione peroxidase, glutathione S-transferase, catalase, total cholinesterase specific activities, total glutathione, total protein content, and lipid peroxidation levels. Imidacloprid displayed its prooxidative and neurotoxic effects predominantly in the kidney of male rats after 24 h of exposure. Our findings suggest that the observed differences in prooxidative and neurotoxic potential of imidacloprid could be related to differences in its metabolism between the sexes. Co-exposure (90-min pre-treatment) with piperonyl butoxide or menadione revealed tissue-specific effect of imidacloprid on total cholinesterase activity. Increased cholinesterase activity in the kidney could be an adaptive response to imidacloprid-induced oxidative stress. In the male rat liver, co-exposure with piperonyl butoxide or menadione exacerbated imidacloprid toxicity. In female rats, imidacloprid+menadione co-exposure caused prooxidative effects, while no such effects were observed with imidacloprid alone or menadione alone. In conclusion, sex-, tissue-, and duration-specific effects of imidacloprid are remarkable points in its toxicity

2020 ◽  
Vol 17 (2) ◽  
pp. 163 ◽  
Author(s):  
Nicoleta Vedeanu ◽  
Cezara Voica ◽  
Dana Alina Magdas ◽  
Bela Kiss ◽  
Maria-Georgia Stefan ◽  
...  

Environmental contextAlthough ruthenium is a technology-critical element used in several new industries, little is known about its environmental impact or possible human health risks. We report a toxicological evaluation of laboratory animals during co-exposure to ruthenium and silver. We identified interactions between the two elements that could lead to unwanted biological effects. AbstractRuthenium is one of the rarest metals on Earth that is classified as a technology-critical element (TCE). Silver, however, is well known for its antibacterial and immunostimulant properties. The increasing use of Ru and Ag in medicine and daily life makes simultaneous exposure possible, with unknown pharmacokinetic or toxicological consequences for the human organism. Thus, the present study investigated the influence of co-exposure to RuIII on the subacute toxicity of Ag ions in rats after repeated daily administration for 28 days of low doses by oral gavage. The subacute toxicity was investigated by the evaluation of several biochemical and hematological parameters, evaluation of specific oxidative stress biomarkers from liver and kidney, and histopathological investigation of liver and kidney tissue samples after 28 days of exposure in female rats. In addition, Ag and Ru concentrations were determined by inductively coupled plasma mass spectrometry (ICP-MS) in urine, liver and kidney parenchyma in male rats. The obtained results showed that co-exposure to low doses of RuIII and Ag did not produce any significant biochemical, hematological or histopathological alterations in the treated female rat groups, except for an increased red cell distribution width (RDW) value. A decrease of urinary excretion of Ag and of the Ag concentration in kidneys was observed in the male rat group co-exposed to RuIII and Ag. This is the first invivo study investigating the toxic effect of co-exposure to low doses of Ag and Ru ions, and the obtained results may justify further research on this subject, mainly on the investigation of possible competitive mechanisms.


1999 ◽  
Vol 18 (3) ◽  
pp. 173-176 ◽  
Author(s):  
Ralph I. Freudenthal ◽  
Richard T. Henrich

Fyrol PCF is a flame retardant chemical widely used to control the flam mability of rigid polyurethane foams and polyester foam systems. It has moderate acute toxicity and was shown to lack mu-tagenic activity. The present study was conducted to determine the toxicity of Fyrol PCF after repeated dietary exposure. Five groups, each consisting of 20 male and 20 female Sprague-Dawley rats, a diet containing either 0, 800, 2500, 7500, or 20,000 ppm Fyrol PCF for 90 days. Data collected include clinical observations, food consumption, body weights, organ weights, urinalysis, hematology, clinical chemistry, brain cholinesterase activity, and gross and microscopic pathology. The mean body weight of animals receiving 20,000 ppm was significantly lower than control values for most study weeks. No clinical signs were noted during cage-side observations. Liver weights were increased in male rats in all treatment groups, and in female rats in both the mid-and high-dose groups. No treatment-related histopathologic changes were observed in the livers of animals that 800, 2500, or 7500 ppm Fyrol PCF; however very mild periportal hepato-cellular swelling was seen in certain of the 20,000 ppm animals. Mean kidney weights were significantly greater in the male animals given 2500, 7500, and 20,000 ppm. Very mild cortical tubular degenerative changes were found in kidneys of male rats that 7500 ppm or 20,000 ppm and in female animals that ingested 20,000 ppm Fyrol PCF. An increase in the incidence of very mild thyroid follicular changes was found in the two highest dose groups. Fyrol PCF did not affect hematology or clinical chemistry parameters, nor did it significantly inhibit brain cholinesterase activity. None of the observed minimal treatment-related changes appear to have human relevance, because they occurred only at the highest doses used in the study. The no observable effect level in this study is 2500 ppm. Fyrol PCF demonstrated low subchronic toxicity in this study.


2003 ◽  
Vol 285 (2) ◽  
pp. H687-H692 ◽  
Author(s):  
M. R. Voss ◽  
J. N. Stallone ◽  
Min Li ◽  
R. N. M. Cornelussen ◽  
P. Knuefermann ◽  
...  

The heat shock proteins (HSPs) are an important family of endogenous, protective proteins that are found in all tissues. In the heart, HSP72, the inducible form of HSP70, has been the most intensely studied. It is well established that HSP72 is induced with ischemia and is cardioprotective. Overexpression of other HSPs also is protective against cardiac injury. Recently, we observed that 17β-estradiol increases levels of HSPs in male rat cardiac myocytes. We hypothesized that there were gender differences in HSP72 expression in the heart secondary to estrogen. To test this hypothesis, we examined cardiac levels of HSP72 by ELISA in male and female Sprague-Dawley rats. In addition, three other HSPs were assessed by Western blot (HSP27, HSP60, and HSP90). To determine whether estrogen status affected HSP72 expression in other muscles or tissues, two other muscle tissues, slow twitch muscle (soleus muscle) and fast twitch muscle (gastrocnemius muscle), were studied as well as two other organs, the kidney and liver. Because HSP72 is cardioprotective, and females are known to have less cardiovascular disease premenopause, the effects of ovariectomy were examined. We report that female Sprague-Dawley rat hearts have twice as much HSP72 as male hearts. Ovariectomy reduced the level of HSP72 in female hearts, and this could be prevented by estrogen replacement therapy. These data show that the expression of cardiac HSP72 is greater in female rats than in male rats, due to upregulation by estrogen.


1978 ◽  
Vol 78 (3) ◽  
pp. 810-822 ◽  
Author(s):  
D J Svoboda

RMI 14, 514 ([5-tetradecycloxy]-2-furancarboxylic acid) represents a new class of hypolipidemic agents which cause unusual ultrastructural changes in liver of male rats and in selected peroxisomal enzymes in liver and kidney of both sexes. Among the principal ultrastructural changes in peroxisomes of male rat liver were (a) cavitation and compartmentalization of the matrix, often giving the appearance of a peroxisome-within-a-peroxisome, and (b) narrow, dense extensions of canaliculi or cisterns from the periphery of the peroxisome, forming partial circlets or surrounding irregular areas of cytoplasm. The unusual enzyme responses were (a) elevation of catalase activity in liver and kidney in female rats, (b) increased activity of three hydrogen peroxide-producing oxidases (urate oxidase, L-alpha-hydroxy acid oxidase, and D-amino acid oxidase) in the liver of both sexes, and (c) elevation of activity of the last two oxidases in male kidney. The peculiar ultrastructural changes in liver peroxisomes combined with the responses of selected peroxisomal enzymes represent unusual modulations or adaptations of these organelles to a hypolipidemic agent, the effects of which have not been reported extensively.


1998 ◽  
Vol 335 (3) ◽  
pp. 619-630 ◽  
Author(s):  
Philip J. SHERRATT ◽  
Margaret M. MANSON ◽  
Anne M. THOMSON ◽  
Erna A. M. HISSINK ◽  
Gordon E. NEAL ◽  
...  

A characteristic feature of the class Theta glutathione S-transferase (GST) T1-1 is its ability to activate dichloromethane and dibromoethane by catalysing the formation of mutagenic conjugates. The level of the GSTT1 subunit within tissues is an important determinant of susceptibility to the carcinogenic effects of these dihaloalkanes. In the present study it is demonstrated that hepatic GST activity towards these compounds can be elevated significantly in female and male Fischer-344 rats by feeding these animals on diets supplemented with cancer chemopreventive agents. Immunoblotting experiments showed that increased activity towards the dihaloalkanes is associated with elevated levels of the GSTT1 subunit in rat liver. Sex-specific effects were observed in the induction of GSTT1 protein. Amongst the chemopreventive agents tested, indole-3-carbinol proved to be the most potent inducer of hepatic GSTT1 in male rats (6.2-fold), whereas coumarin was the most potent inducer of this subunit in the livers of female rats (3.5-fold). Phenobarbital showed significant induction of GSTT1 only in male rat liver and had little effect in female rat liver. Western blotting showed that class Alpha, Mu and Pi GST subunits are not co-ordinately induced with GSTT1, indicating that the expression of GSTT1 is determined, at least in part, by mechanisms distinct from those that regulate levels of other transferases. The increase in amount of hepatic GSTT1 protein was also reflected by an increase in the steady-state level of mRNA in response to treatment with chemopreventive agents and model inducers. Immunohistochemical detection of GSTT1 in rat liver supported the Western blotting data, but showed, in addition to cytoplasmic staining, significant nuclear localization of the enzyme in hepatocytes from some treated animals, including those fed on an oltipraz-containing diet. Significantly, the hepatic level of cytochrome P-450 2E1, an enzyme which offers a detoxification pathway for dihaloalkanes, was unchanged by the various inducing agents studied. It is concluded that the induction of GSTT1 by dietary components and its localization within cells are important factors that should be considered when assessing the risk dihaloalkanes pose to human health.


2012 ◽  
Vol 63 (4) ◽  
pp. 417-427 ◽  
Author(s):  
Mariana Tozlovanu ◽  
Delphine Canadas ◽  
Annie Pfohl-Leszkowicz ◽  
Christine Frenette ◽  
Robert J. Paugh ◽  
...  

AbstractIn the present study the photoreactivity of the fungal carcinogen ochratoxin A (OTA) has been utilised to generate authentic samples of reduced glutathione (GSH) and N-acetylcysteine (NAC) conjugates of the parent toxin. These conjugates, along with the nontoxic OTα, which is generated through hydrolysis of the amide bond of OTA by carboxypeptidase A, were utilised as biomarkers to study the metabolism of OTA in the liver and kidney of male and female Dark Agouti rats. Male rats are more susceptible than female rats to OTA carcinogenesis with the kidney being the target organ. Our studies show that the distribution of OTA in male and female rat kidney is not significantly different. However, the extent of OTA metabolism was greater in male than female rats. Much higher levels of OTα were detected in the liver compared to the kidney, and formation of OTα is a detoxification pathway for OTA. These findings suggest that differences in metabolism between male and female rats could provide an explanation for the higher sensitivity of male rats to OTA toxicity


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Murtala Akanji Abdullahi ◽  
Elijah Oladapo Oyinloye ◽  
Akinyinka Alabi ◽  
Aderonke Adeyinka Aderinola ◽  
Luqman Opeyemi Ogunjimi ◽  
...  

Abstract Objectives Several studies have established the ethnobotanical benefits of Pupalia lappacea (PL) in laboratory animals without extensive toxicological evaluation of its safety profiles. Thus, an extensive toxicological investigation of sub-chronic oral administration of the hydroethanol leaf extract of P. lappacea in rodents was carried out in this study. Methods Different groups of rats were treated orally with the extract (10, 50 and 250 mg/kg) daily for 90 consecutive days. The control group received distilled water (10 mL/kg). After 90 days, some rats were left for additional 30 days without treatment for reversibility study. Blood and organs samples were collected for different evaluations at the end of study periods. Results The extract decreased the bodyweights, feeding and water intakes in female rats. PL increased the weights of the liver and kidney in male rats. PL increased the red blood cell (RBC), packed cell volume (PCV), hemoglobin (Hb), triglycerides (TRIG), cholesterol and high density lipoprotein (HDL) contents in rats. PL (250 mg/kg) significantly reduced the sperm motility and serum testosterone level. Cyto-architectural distortions of the testes, liver and spleen were visible. Conclusions The findings showed that P. lappacea is relatively safe at lower doses but cautions should be taken at higher dose.


Author(s):  
Devangam Sheshadri Shekar

Object: The present investigation has been carried out to find out the effect of yohimbine on clomipramine-induced sexual dysfunction in male rats.Methods: The male rats were treated with clomipramine and yohimbine simultaneously for 60 days. During the treatment, all the male rats werechallenged with the female rats which are in estrous phase and their sexual behavior was observed under dim red light. Half of the animals in each group and remaining on 60 day were sacrificed, blood was collected and serum separated. Testis was collected and preserved in 10% formalin forsubsequent histopathological examination. thResults: The study reveals that yohimbine failed to antagonize the clomipramine-induced sexual dysfunction in male rats in all aspects, except thepartial improvement in the sexual behavior.Conclusion: Yohimbine a well-known aphrodisiac failed to antagonize the clomipramine-induced sexual dysfunction in male rats. The decrease intestosterone levels, a decrease in spermatozoa count were continued even in the presence of yohimbine except improvement in the sexual behaviorparameters. Hence, yohimbine could not be a safe antidote against clomipramine-induced sexual dysfunction in male rats.Keywords: Yohimbine, Clomipramine, Testosterone, Male rat sexual competence, Testicular damage.


2005 ◽  
Vol 24 (6) ◽  
pp. 451-467 ◽  
Author(s):  
Raymond G. York ◽  
John Barnett ◽  
Michael F. Girard ◽  
David R. Mattie ◽  
Marni V. K. Bekkedal ◽  
...  

A developmental neurotoxicity study was conducted to generate additional data on the potential functional and morphological hazard to the central nervous system caused by ammonium perchlorate in offspring from in utero and lactation exposure. Female Sprague-Dawley rats (23 to 25/group) were given continuous access to 0 (carrier), 0.1, 1.0, 3.0, and 10.0 mg/kg-day perchlorate in the drinking water beginning 2 weeks prior to mating and continuing through day 10 of lactation for the behavioral function assessment or given continuous access to 0 (carrier), 0.1, 1.0, 3.0, and 30.0 mg/kg-day beginning on gestation day 0 and continuing through day 10 of lactation for neurodevelopment assessments. Motor activity was conducted on postpartum days 14, 18, and 22 and juvenile brain weights, neurohistopathological examinations, and regional brain morphometry were conducted on postpartum days 10 and 22. This research revealed a sexually dimorphic response, with some brain regions being larger in perchlorate-treated male rats than in comparable controls. Even so, there was no evidence of any obvious exposure-related effects on male rat brain weights or neuropathology. The most consistent exposure-related effect in the male pups was on the thickness of the corpus callosum, with both the right- and left-sided measures of the thickness of this white matter tract being significantly greater for the male pups in the 0.1 and 1.0 mg/kg-day exposure groups. The behavioral testing suggests prenatal exposure to ammonium perchlorate does not affect the development of gross motor movements in the pups.


1974 ◽  
Vol 142 (2) ◽  
pp. 273-277 ◽  
Author(s):  
Jan-Åke Gustafsson ◽  
Åke Pousette

The regulatory mechanisms involved in the control of the nuclear NADPH-dependent 3-ketosteroid 5α-reductase (5α-reductase) activity were studied in liver, kidney and prostate. The substrate used was [1,2-3H]androst-4-ene-3,17-dione (androstenedione) (for liver and kidney) or [4-14C]androstenedione (for prostate). The hepatic nuclear 5α-reductase activity was greater in female than in male rats, was greater in adult than in prepubertal female rats, increased after castration of male rats, but was not affected by treatment with testosterone propionate or oestradiol benzoate. These regulatory characteristics are in part different from those previously described for the hepatic microsomal 5α-reductase. The renal nuclear metabolism of androstenedione, i.e. 5α reduction and 17β-hydroxy steroid reduction, was relatively unaffected by sex, age, castration and treatment with testosterone propionate. However, treatment of castrated male rats with oestradiol benzoate led to a significant increase in the 5α-reductase activity and a significant decrease in the 17β-hydroxy steroid reductase activity. Finally, the nuclear 5α-reductase activity in prostate was androgen-dependent, decreasing after castration and increasing after treatment with testosterone propionate. In conclusion, the nuclear 5α-reductase activities in liver, kidney and prostate seem to be under the control of distinctly different regulatory mechanisms. The hypothesis is presented that whereas the prostatic nuclear 5α-reductase participates in the formation of a physiologically active androgen, 5α-dihydrotestosterone, this may not be the true function of the nuclear 5α-reductase in liver and kidney. These enzymes might rather serve to protect the androgen target sites in the chromatin from active androgens (e.g. testosterone) by transforming them into less active androgens (e.g. 5α-androstane-3,17-dione and/or 5α-dihydrotestosterone).


Sign in / Sign up

Export Citation Format

Share Document