Practical Application of Microcapsulation for Toxicity Studies Using Bromodichloromethane as a Model Compound

1989 ◽  
Vol 8 (6) ◽  
pp. 1177-1187
Author(s):  
Y. Aida ◽  
M. Ando ◽  
K. Takada ◽  
J Momma ◽  
H. Yoshimoto ◽  
...  

Gelatin-starch syrup (food grade) microcapsulation was applied for toxicology studies of bromodichloromethane (BDCM). BDCM concentrations were stable for 120 days in the microcapsules and for 9 months when incorporated in the powder diet. BDCM concentration in the blood following the administration of microcapsules in olive oil suspension was retained at higher levels than when BDCM was administered as olive oil solution. Subsequently, the microcapsules were mixed in powder diet and were given at concentrations of microcapsulated BDCM of 0, 0.024, 0.072, and 0.215% to groups of 7 male Wistar rats for 1 month. For comparison, BDCM dissolved in olive oil was administered by gavage to groups of 7 male rats for 1 month at dosage levels adjusted to those in the feeding study (0, 20, 60, and 180 mg/kg body weight). Suppression of body weight gain was seen in the high-dosage groups in both the feeding and the gavage studies and was more severe in the former. Similar histopathologic lesions in the liver were shown in both studies, including vacuolization, swelling, and single necrosis of liver cells. Hepatic cord irregularity and bile duct proliferation were observed in the feeding study but not the gavage study. Serum biochemical changes, such as decreases in glucose, triglyceride, and cholinesterase levels, which reflected the histopathologic findings in the liver, were also observed in both studies. Accordingly, the microcapsulation process was proved to pose no qualitative toxic effects on toxicity of BDCM in short-term toxicity studies. It is concluded that the application of microcapsulation is useful for toxicity tests of volatile chemicals when incorporated into food.

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Abdel-Tawab H. Mossa ◽  
Amel A. Refaie ◽  
Amal Ramadan ◽  
Jalloul Bouajila

This study was carried out to evaluate the adverse effects of exposure to prallethrin on oxidant/antioxidant status and liver dysfunction biomarkers and the protective role ofOriganum majoranaessential oil (EO) in rat. Male rats were divided into 4 groups: (i) received only olive oil (ii) treated with 64.0 mg/kg body weight prallethrin (1/10 LD50) in olive oil via oral route daily for 28 days, (iii) treated with 64.0 mg/kg body weight prallethrin (1/10 LD50) and EO (160 μL/kg b.wt.) in olive oil and (iv) received EO (160 μL/kg b.wt.) in olive oil via oral route twice daily for 28 days. Prallethrin treatment caused decrease in body weight gain and increase in relative liver weight. There was a significant increase in the activity of serum marker enzymes, aspartate transaminase, alanine transaminase, and alkaline phosphatase. It caused increase in thiobarbituric acid reactive substances and reduction in the activities of superoxide dismutase, catalase, and glutathione-S-transferase in liver. Consistent histological changes were found in the liver of prallethrin treatment. EO showed significant protection with the depletion of serum marker enzymes and replenishment of antioxidant status and brought all the values to near normal, indicating the protective effect of EO. We can conclude that prallethrin caused oxidative damage and liver injury in male rat and co-administration of EO attenuated the toxic effect of prallethrin. These results demonstrate that administration of EO may be useful, easy, and economical to protect human against pyrethroids toxic effects.


2019 ◽  
Vol 15 (2) ◽  
pp. 140-147
Author(s):  
Magdy M. Ismail ◽  
El-Tahra M. Ammar ◽  
Abd El-Wahab E. Khalil ◽  
Mohamed Z. Eid

Background and Objective: Yoghurt, especially bio-yoghurt has long been recognized as a product with many health benefits for consumers. Also, honey and olive oil have considerable nutritional and health effects. So, the effect of administration of yoghurt made using ABT culture and fortified with honey (2 and 6%), olive oil (1 and 4%) or honey + olive oil (2+1 and 6+4% respectively) on some biological and hematological properties of rats was investigated.Methods:The body weight gain, serum lipid level, blood glucose level, serum creatinine level, Glutamic Oxaloacetic Transaminase (GOT) activity, Glutamic Pyruvic Transaminase (GPT) activity, leukocytes and lymphocytes counts of rats were evaluated.Results:Blending of bio-yoghurt with rats' diet improved body weight gain. Concentrations of Total plasma Cholesterol (TC), High-Density Lipoprotein cholesterol (HDL), Low-Density Lipoprotein cholesterol (LDL), Very Low-Density Lipoprotein cholesterol (VLDL) and Triglycerides (TG) significantly lowered in plasma of rats fed bio-yoghurt. Levels of TC, LDL, VLDL, and TG also decreased in rat groups feed bio-yoghurt supplemented with honey and olive oil. LDL concentrations were reduced by 10.32, 18.51, 34.17, 22.48, 43.30% in plasma of rats fed classic starter yoghurt, ABT yoghurt, ABT yoghurt contained 6% honey, ABT yoghurt contained 4% olive oil and ABT yoghurt contained 6% honey + 4% olive oil respectively. The blood glucose, serum creatinine, GOT and GPT values of rats decreased while white blood cells and lymphocytes counts increased by feeding bioyoghurt contained honey and olive oil.Conclusion:The findings enhanced the multiple therapeutic effects of bio-yoghurt supplemented with honey and olive oil.


2018 ◽  
Vol 315 (1) ◽  
pp. E29-E37 ◽  
Author(s):  
Mariana Peduti Halah ◽  
Paula Beatriz Marangon ◽  
Jose Antunes-Rodrigues ◽  
Lucila L. K. Elias

Neonatal nutritional changes induce long-lasting effects on energy homeostasis. Adiponectin influences food intake and body weight. The aim of this study was to investigate the effects of neonatal nutritional programming on the central stimulation of adiponectin. Male Wistar rats were divided on postnatal (PN) day 3 in litters of 3 (small litter, SL), 10 (normal litter, NL), or 16 pups/dam (large litter, LL). We assessed body weight gain for 60 days, adiponectin concentration, and white adipose tissue weight. We examined the response of SL, NL, and LL rats on body weight gain, food intake, oxygen consumption (V̇o2), respiratory exchange ratio (RER), calorimetry, locomotor activity, phosphorylated-AMP-activated protein kinase (AMPK) expression in the hypothalamus, and uncoupling protein (UCP)-1 in the brown adipose tissue after central stimulus with adiponectin. After weaning, SL rats maintained higher body weight gain despite similar food intake compared with NL rats. LL rats showed lower body weight at weaning, with a catch up afterward and higher food intake. Both LL and SL groups had decreased plasma concentrations of adiponectin at PN60. SL rats had increased white adipose tissue. Central injection of adiponectin decreased body weight and food intake and increased V̇o2, RER, calorimetry, p-AMPK and UCP- 1 expression in NL rats, but it had no effect on SL and LL rats, compared with the respective vehicle groups. In conclusion, neonatal under- and overfeeding induced an increase in body weight gain in juvenile and early adult life. Unresponsiveness to central effects of adiponectin contributes to the imbalance of the energy homeostasis in adult life induced by neonatal nutritional programming.


1988 ◽  
Vol 255 (4) ◽  
pp. R616-R621 ◽  
Author(s):  
J. O. Hill ◽  
J. C. Anderson ◽  
D. Lin ◽  
F. Yakubu

The effects of differences in meal frequency on body weight, body composition, and energy expenditure were studied in mildly food-restricted male rats. Two groups were fed approximately 80% of usual food intake (as periodically determined in a group of ad libitum fed controls) for 131 days. One group received all of its food in 2 meals/day and the other received all of its food in 10-12 meals/day. The two groups did not differ in food intake, body weight, body composition, food efficiency (carcass energy gain per amount of food eaten), or energy expenditure at any time during the study. Both food-restricted groups had a lower food intake, body weight gain, and energy expenditure than a group of ad libitum-fed controls. In conclusion, these results suggest that amount of food eaten, but not the pattern with which it is ingested, has a major influence on energy balance during mild food restriction.


1990 ◽  
Vol 259 (3) ◽  
pp. R579-R584 ◽  
Author(s):  
S. Rivest ◽  
D. Richard

The effects of a hypothalamic paraventricular nucleus (PVN) lesion on energy balance were investigated in exercise-trained rats. Male Wistar rats weighing initially 250 g were divided into four groups. Two groups of rats underwent a bilateral PVN lesion, whereas the two remaining groups were sham operated. The PVN lesions were done electrolytically. One group from each surgical treatment was exercised, while the other group was kept in sedentary conditions. Rats were exercised on a rodent motor-driven treadmill at moderate intensity, 1 h/day for 21 consecutive days. Food intake and body weight were measured each day during the study. At the end of the treatment period, rats were killed, and carcasses were analyzed for their energy content. Serum corticosterone was measured by a competitive protein-binding assay. Energy gain and energy intake were lower in exercised rats than in sedentary controls, regardless of whether they were sham or PVN lesioned. Concurrently, there was no difference in the energy gain between PVN-lesioned and sham-operated rats, despite the fact that PVN-lesioned rats ended the experiment with a larger body weight than the sham-lesioned animals. Serum corticosterone levels were lower in PVN-lesioned rats than in sham-lesioned rats. In conclusion, the present results indicate that the PVN, the hypothalamic nucleus predominantly controlling the pituitary-adrenal axis activity, is not a prominent structure in the regulation of energy balance in exercised male Wistar rats.


2013 ◽  
Vol 32 (2) ◽  
pp. 113-122 ◽  
Author(s):  
John T. Houpt ◽  
Glenn J. Leach ◽  
Larry R. Williams ◽  
Mark S. Johnson ◽  
Gunda Reddy

4-Amino-2-nitrotoluene (4A2NT; CAS 119-32-4) is a degradation product of 2,4-dinitrotoluene. The toxicity data on 4A2NT are limited. Therefore, we collected toxicity data from rats to assess environmental and human health effects from exposures. The approximate lethal dose for both sexes was 5000 mg/kg. A 14-day toxicity study in rats was conducted with 4A2NT in the feed at concentrations of 0, 125, 250, 500, 1000, and 2000 ppm. Based on a 14-day oral dose range toxicity study with 4A2NT in the feed, 2000 ppm was selected as highest concentration for a subsequent 90-day study. An oral 90-day subchronic toxicity study in rats was conducted with concentrations of 0, 500, 1000, or 2000 ppm of 4A2NT in the feed. The calculated consumed doses of 4A2NT in the feed were 0, 27, 52, or 115 mg/kg/d for males and 0, 32, 65, or 138 mg/kg/d for females. A no-observed adverse effect level could not be determined. The lowest observed adverse effect level was 27 mg/kg/d for males and 32 mg/kg/d for female rats based upon decreased body weight gain. The decreased body weight gain in male rats was the most sensitive adverse event observed in this study and was used to derive a benchmark dose (BMD). A BMD of 23.1 mg/kg/d and BMD with 10% effect level of 15.5 mg/kg/d were calculated for male rats, which were used to derive an oral reference dose (RfD). The human RfD of 1.26 μg/kg/d was derived using current United States Environmental Protection Agency guidelines.


2000 ◽  
pp. 406-410 ◽  
Author(s):  
M Tena-Sempere ◽  
L Pinilla ◽  
LC Gonzalez ◽  
J Navarro ◽  
C Dieguez ◽  
...  

The obese gene (ob) product, leptin, has recently emerged as a key element in body weight homeostasis, neuroendocrine function and fertility. Identification of biologically active, readily synthesized fragments of the leptin molecule has drawn considerable attention, as they may provide a powerful tool for detailed characterization of the biological actions of leptin in different experimental settings. Recently, a fragment of mouse leptin protein comprising amino acids 116-130, termed leptin(116-130) amide, was shown to mimic the effects of the native molecule in terms of body weight gain and food intake, and to elicit LH and prolactin (PRL) secretion in vivo. As a continuation of our previous experimental work, the present study reports on the effects of leptin(116-130) amide on basal and stimulated testosterone secretion by adult rat testis in vitro. In addition, a comparison of the effects of human recombinant leptin and leptin(116-130) amide at the pituitary level on the patterns of LH, FSH, PRL and GH secretion is presented. As reported previously by our group, human recombinant leptin(10(-9)-10(-7)M) significantly inhibited both basal and human chorionic gonadotrophin (hCG)-stimulated testosterone secretion in vitro. Similarly, incubation of testicular tissue in the presence of increasing concentrations of leptin(116-130) amide (10(-9)-10(-5)M) resulted in a dose-dependent inhibition of basal and hCG-stimulated testosterone secretion; a reduction that was significant from a dose of 10(-7)M upwards. In addition, leptin(116-130) amide, at all doses tested (10(-9)-10(-5)M), significantly decreased LH and FSH secretion by incubated hemi-pituitaries from adult male rats. In contrast, in the same experimental protocol, recombinant leptin(10(-9)-10(-7)M) was ineffective in modulating LH and FSH release. Finally, neither recombinant leptin nor leptin(116-130) amide were able to change basal PRL and GH secretion in vitro. Our results confirm the ability of leptin, acting at the testicular level, to inhibit testosterone secretion, and map the effect to a domain of the leptin molecule that lies between amino acid residues 116 and 130. In addition, we provide evidence for a direct inhibitory action of leptin(116-130) amide on pituitary LH and FSH secretion, a phenomenon not observed for the native leptin molecule, in the adult male rat.


1978 ◽  
Vol 176 (3) ◽  
pp. 777-784 ◽  
Author(s):  
Helen P. Glenny ◽  
David N. Brindley

1. Male rats were injected daily for 5 days with 0.15m-NaCl, corticotropin, cortisol or l-thyroxine and the rates of glycerolipid synthesis were measured in the livers after intraportal injection of [14C]palmitate and [3H]glycerol. 2. Injection of all three hormones decreased the rates of body-weight gain. 3. Cortisol treatment increased the weight of the liver relative to body weight. 4. Thyroxine treatment increased the relative rate of triacylglycerol synthesis from [3H]glycerol and decreased the relative accumulation of 3H and 14C in diacylglycerol. It did not significantly alter the accumulation of these isotopes in phosphatidate nor the activity of the soluble phosphatidate phosphohydrolase in the total liver. However, this activity increased by 1.5-fold when expressed relative to the soluble protein of the liver. The increased triacylglycerol synthesis appears to be related to a general increase in the turnover of fatty acids in the liver. 5. Treatment with cortisol and corticotropin increased the relative rate of triacylglycerol synthesis from [3H]glycerol, decreased the accumulation of 3H in phosphatidate and increased the flux of both isotopes from phosphatidate to diacylglycerol. This appeared to be caused by the increased activity of the soluble phosphatidate phosphohydrolase that was observed in the livers of the cortisol-treated rats. 6. It is proposed that cortisol could be directly or indirectly involved in increasing the activity of hepatic phosphatidate phosphohydrolase in starvation, diabetes, laparotomy, subtotal hepatectomy, liver damage, ethanol feeding and in obesity. This enzyme adaptation could contribute to the potential of the liver to increase its synthesis and accumulation of triacylglycerols or to secrete very-low-density lipoproteins.


Author(s):  
N Ahmad ◽  
S Majumder ◽  
MA Miah ◽  
MJ Uddin

An investigation on Long Evans male rats fed with different edible fats and oils was conducted in the Department of Physiology, Bangladesh Agricultural University, Mymensingh during a period of 7 weeks (1st April to 19th May, 2005) to determine and to compare the effect of feeds on body weight gain and on weights of some selected organs (heart, liver and kidney) removing the impact of unequal feed intake. A total of 20, six-week old male rats were randomly divided into A, B, C and D groups. Each group consisted of 5 rats. Rats were fed rat pellets purchased from ICDDR,B, Dhaka supplemented with beef fat in group A, fish fat in group B and soybean oil in group C while group D was considered as control and fed only with rat pellets. The concentration of fats and oils were 7% of normal diet and fed for 7 weeks. The highest weekly mean body weight gain (19.90g) adjusted for unequal feed intake was achieved by the rats of beef fat supplemented group A, followed by the rats of soybean oil supplemented group C (19.76g) and fish fat supplemented group B (15.67g). But none of the adjusted means of weekly body weight gain differed significantly (p > 0.05) from the control. Insignificant increases in heart weight were recorded in all treated rats and the maximum weight was in fish oil treated ones. Not much differences were recorded in the kidney weights rather beef oil treated rats' kidney had the lowest mean weight. A significantly (p < 0.01) higher liver weight was recorded in group B & C compared to control (group D), though the differences between A & D were insignificant. It could be concluded that fats and oils are harmful for the rat's body especially on liver and heart. Key words: Edible fats and oils, rat, body weight, organ weight, analysis of variance, covariance DOI = 10.3329/bjvm.v5i1.1326 Bangl. J. Vet. Med. (2007). 5 (1 & 2): 107-110


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