Effects of DMSO on SGOT during hypothermia in adrenalectomized rats

Experimental pathology of T-2 toxicosis and mycoplasma infection on performance and hepatic functions of broiler chickens

This experiment was conducted using 192 day-old Ross 308 chicks, divided into 4 groups of 4 replicate consisting 48 birds. Group I was fed a control diet, Group II was fed control diet supplemented with 0.5 ppm T-2 toxin for 5 weeks, Group III was fed control diet supplemented with 8 × 10(8) cfu/mL of Mycoplasma gallisepticum, and group IV was fed control diet supplemented by T-2 toxin and Mycoplasma gallisepticum. Body weight and feed conversation ratio (FCR), relative organ weights, clinical signs, biochemical characteristics, and gross and histopathological lesions were recorded in the experimental groups at the end of the second and fifth weeks of age. Body weight and relative weights of bursa of Fabricius, thymus, and spleen decreased and FCR increased significantly (P ≤ 0.05), but the relative weights of liver and kidney showed no significant decrease (P ≤ 0.05) in the serum total proteins, albumin, and increase in aspartate aminotransferase and alanine transaminase were observed in T-2 toxin and T-2 accompanied with Mycoplasma fed birds when compared to the control group. Liver was enlarged, friable, and yellowish discoloration with distended gall bladder was noticed. Lymphoid organs such as bursa of Fabricius, thymus, and spleen were atrophied in group II and group IV throughout the study. Microscopically, liver showed vacuolar degeneration of hepatocytes, with increased Kupffer cell activity, bile duct epithelial hyperplasia, and infiltration of inflammatory cells. Kidney showed vacuolar degeneration of tubular epithelium along with pyknotic nuclei. Lymphoid organs showed lymphocytolysis and depletion with prominent reticuloepithelial cells. Proventriculus revealed desquamation of villous epithelial cells and lymphoid infiltration in submucosa. Heart showed mild hemorrhage with infiltration of inflammatory cells. Lung showed edema and inflammatory cells in the bronchioles. Trachea showed desquamation and erosions of mucosa. Proliferation of mucosal glands with increased mucous secretion was obvious. Air sacs showed thickening with presence of inflammatory cells and edema.

Protective role of zinc during aluminum-induced hepatotoxicity

The study was carried out to assess the role of zinc (Zn) in mitigating the biochemical alterations induced by aluminum (Al) in rat liver. Rats were divided into four groups: normal control, Al treated (AlCl3, 100 mg/kg b.wt./day), Zn treated (ZnSO4, 227 mg/L drinking water), and combined Al + Zn treated. Al and zinc treatments were given for a total duration of 2 months. Al treatment caused a significant increase in the activity of alkaline phosphatase (ALP), but decreased aspartate aminotransferase (AST) and alanine aminotranferase (ALT) activities, which showed the reverse trend following Zn supplementation. Levels of lipid peroxidation (LPx) and activities of catalase and glutathione-S-transferase (GST) were significantly decreased following Al treatment, which, however, were increased significantly in Zn co-treated rats. Further Al exposure showed a significant increase in reduced glutathione (GSH) content as well as activities, of superoxide dismutase (SOD) and glutathione reductase (GR). However, Zn supplementation to Al-treated rats brought down the raised levels of reduced (GSH) and SOD to within normal limits, but caused no effect on GR activity. Furthermore, Al treatment also resulted in alterations in liver histoarchitecture with disruption of hepatic cords and increased vacuolization, which were close to normal following Zn supplementation. The present study reveals that Zn is effective in attenuating the liver damage inflicted by Al toxicity.

Sub-acute deltamethrin and fluoride toxicity induced hepatic oxidative stress and biochemical alterations in rats

The current study investigated the effects of deltamethrin, fluoride (F(-)) and their combination on the hepatic oxidative stress and consequent alterations in blood biochemical markers of hepatic damage in rats. Significant hepatic oxidative stress and hepatic damage were observed in the toxicant exposed groups. These changes were higher in the deltamethrin-F(-) co-exposure treatment group, depicting a positive interaction between the two chemicals.

Acute and repeated-doses (28 days) toxicity study of Hypericum polyanthemum Klotzsch ex Reichardt (Guttiferare) in mice

Hypericum polyanthemum, a South Brazilian species showed antidepressant-like and antinociceptive effects in rodents. Since limited information is available on the toxicity and safety profile of the Hypericum genus, we therefore investigated whether H. polyanthemum cyclo-hexane extract (POL) treatment could be associated with toxicity in preclinical setting using mice as an experimental model. These toxicity studies were based on the guidelines of the Organization for Economic Cooperation and Development (OECD-guidelines 423 and 407). Animals received POL single dose (2000 mg/kg, p.o.) or daily for 28-days (90, 450 and 900 mg/kg, p.o.). Acute toxicity study did not detect any clinical signs, changes in behavior or mortality. In repeated dose toxicity study, POL affected the body weight gain and induced biochemical, hematological and liver histological changes at 450 and 900 mg/kg. Mice treated with POL 90 mg/kg did not show any toxicity signs. In conclusion H. polyanthemum can be classified as safe (category 5) according to OECD acute toxicity parameters. However, the alterations observed after repeated treatment with high doses suggest that the liver could be the target organ on potential H. polyanthemum toxicity and point to the need of further toxicity studies.

Studies on biochemical changes in subacute thiodicarb toxicity in rats

Effect of thiodicarb was investigated on various biochemical parameters and blood enzymes in adult male Wistar rats following its intraperitoneal administration at rates of 2.9 and 5.8 mg/kg daily for 28 days. Rats did not exhibit any marked changes in their gross behavioral signs and symptoms. Thiodicarb caused hyperglycemia in rats; however, increase in plasma glucose level was nonsignificant. There was no effect on total plasma protein indicating no severe damage to vital organs and no interference with protein metabolism in rats. Thiodicarb did not cause significant change in blood urea and creatinine levels, thus indicating to have no toxic effect on kidneys in rats. It did not affect aspartate aminotransferase (AST) level except a significant increase in AST level only on 7th day of treatment. There was an increase in the levels of alanine aminotransferase (ALT), but this trend reversed on 14th and 28th day. Thiodicarb did not alter significantly the levels of alkaline phosphatase in rats. It caused inhibition of plasma and brain acetylcholinesterase (AChE) in rats throughout the entire period of 28 days of treatment, which was dose-dependent. The findings of this investigation indicated that thiodicarb did not effect or alter much the various biochemical profiles except inhibiting AChE following i.p. administration up to 28 days in adult male rats.

Toxicological approach in chronic exposure to lead on reproductive functions in female rats (rattus norvegicus)

Lead being a toxic cumulative poison and an environmental pollutant, experiments were conducted at an oral chronic dose of (60 mg/kg/day) for 90 days on adult female rats (Rattus Norvegicus) and its effect on the reproductive functions in relation to the biochemical effects was studied. It was observed that the chronic dose of lead caused an elevation in the level of proteins, acid phosphatase, alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase in all the soft tissues studied indicating tissue damage. It also inhibited the level of acetylcholinesterase in all the tissues. Fertility tests by pairing treated females with males showed that lead-treated female showed irregular estrous cycle and the fertility rate dropped to 40% as female pups of lead-treated mothers showed loss in weight, high mortality rate, poor growth rate, and late vaginal opening. Histological studies of ovary showed atresia in all the stages of folliculogenesis sustaining the poor fertility observations. The present study revealed that lead caused great tissue damage and affected reproductive performance of female rats at a chronic dose.

Subchronic toxicity study of urea molasses mineral block in kids

A study was conducted on twenty indigenous goat kids allocated into two different groups. All animals were offered ad libitum rice straw and berseem hay (40:60). Group I (T(1)) was fed concentrate mixture (100 g/d). Group II (T(2)) was supplemented with urea molasses mineral block (200 g/d). The experiment lasted for 90 days. There was significant decrease in serum sodium (60.68 mEq/L), increase in serum potassium (34.50 mEq/L) and increased activity of AST (340.42 U/L) and ALT (164.96 U/L) was observed in kids of group T(2) in comparison to the controls (T(1)). On histopathological examination mild degenerative changes in kidney of group T(2) with congestion in intertubular vessel, granular cytoplasm of the epithelial cells in PCT and DCT, necrosis and swelling of the epithelial cells, congestion of vessels and cloudy swelling was observed in PCT and DCT. Albuminious mass was also present in tubule. On histopathological observation of liver of kid of group T(2) oedema in liver parenchyma and proliferation of fibrious tissue in periportal area was observed.

Effects of repeated topical application of dichlorvos on blood enzymes and its toxicity in buffalo calves (Bubalus bubalis)

Dichlorvos was applied as spray at 1 and 2% concentrations daily for a period of 28 and 21 consecutive days, respectively to buffalo calves. Animals sprayed with 1% dichlorvos displayed mild to moderate clinical signs of toxicosis during the 4th week of exposure. The higher concentration (2%) produced clinical signs of poisoning after 12-16 applications, and was lethal to one of three animals. Daily spraying of dichlorvos at both concentrations inactivated erythrocyte cholinesterase (ChE) (15-21%), plasma ChE (17-20%) and serum carboxylesterase (5-10%) within 3 days. The extent of inhibition of esterases was increased with repeated treatment and maximal inhibition of erythrocyte ChE (80-89%), plasma ChE (81-91%) and serum carboxylesterase (33-54%) with 1 and 2% concentrations was observed on the 28th and 21st day after start of application, respectively. In surviving animals, blood esterases remained inactivated to the extent of 14-65% on the 14th day after the termination of treatment. Dichlorvos at both concentrations significantly (P less than 0.01) elevated the serum levels of aspartate aminotransferase, alanine aminotransferase, acid phosphatase and alkaline phosphatase. The activities of these enzymes in surviving animals recovered to control values within 14 days after the final application of dichlorvos.

The effects of benzo(a)pyrene on rat liver lysosomes

An i.p. injection of benzo(a)pyrene (BP; 10 mg/kg) into rats led to the progressive release of hepatic, beta-glucuronidase (beta-Gluc), beta-galactosidase (beta-Gal) and beta-N-acetylglucosaminidase (beta-Glm). This occurred prior to the appearance of altered cells or cell populations from which malignant transformations may gradually develop. The in vitro studies on the latency of beta-Gluc, Beta-Gal and beta-Glm in the lysosome-enriched rat liver suspension treated with BP showed that concentrations of 10(-7) M, 10(-6) M and 10(-5) M significantly decrease latency of all three lysosomal enzymes, the effect being time-dependent. These concentrations of BP did not alter the activities of beta-Gluc, b-Gal and beta-Glm in vitro. No significant alterations were observed in total enzyme activities, following in vivo and in vitro BP administration. BP exerts its effect on rat liver lysosomes by modifying the structural properties of the lysolemma, and may represent an early precarcinogenic change.