Intermediate-term toxicity of repeated orally administered doses of the anti-malarial β-artemether in dogs

The artemisinin derivative beta-artemether, an anti-malarial, was evaluated for its toxicity and tolerability in a 2-week, multiple-dose study in dogs. Eight beagle dogs (4 females, 4 males) were given beta-artemether by oral gavage 3 times daily at 45 mg/kg/dosing (a total daily dose-level of 135 mg/kg) for 2 weeks. This beta-artemether dose regime was well tolerated. Body weight changes were normal although feed consumption during the treatment period reduced compared to that of the pre-trial period. Clinical signs were transient spells of soft to liquid feces. On completion of the treatment period, the animals were sacrificed and submitted to a full macroscopic post-mortem examination. Designated organs were weighed and a complete light microscopic examination was performed on 43 selected tissues from 1 animal per sex, and on the liver, kidneys, thymus, mandibular lymph nodes and lungs of the three other animals per sex. Major findings were high liver weight and histopathologic findings of slight diffuse hepatocellular hypertrophy and distal tubular dilatation, together with flattened epithelium, in the kidneys. With the dose regime used in this trial beta-artemether produced no clinical or apparent histopathological signs of neurotoxicity in dogs.     

Evaluation of the Toxicological Profile of the Leaves and Young Twigs of Caesalpinia Bonduc (Linn) Roxb

Acute and sub-acute toxicological effects of ethanolic extract of the leaves and young twigs of Caesalpinia bonduc were carried out on albino rats. Single extract doses from 2000 to 5000 mg/kg body weight were administered orally and monitored for 14 days in acute study, while extract doses from 200 to 1600 mg/kg body weight were orally administered daily for 28 days in sub-acute study and recovery was assessed 14 days after dosing. Biochemical, haematological and histopathological examinations were carried out. There was no mortality in the experimental animals in all acute treatment doses. However, there were significant alterations in the biomarkers and induced cellular damage to the liver in all acute treatment doses. In the sub-acute toxicity treatment, the assessed biomarkers were unaffected at extract dose of 200 mg/kg body weight compared to control, while significant changes were observed in rats administered with extract doses of 400 mg/kg body weight and above. No significant difference was observed between the tested groups and the recovery groups in the sub-acute toxicity study. In conclusion, the ethanolic extract of C. bonduc could be toxic to selected organs of the rat body in acute and sub-acute treatments.     

全反式维甲酸对生长发育期大鼠实质器官的损伤

目的 探讨体内过量全反式维甲酸（ATRA）对生长发育期SD大鼠的脑、心、肺、肝、肾和脾的影响。方法 以48只3周雄性SD大鼠为实验对象,随机分为对照组和3个实验组,ATRA剂量分别为40、60、80 mg/(kg·d),每组12只,进行连续10 d ATRA灌胃处理,记录SD大鼠每日体重,于灌胃第10天解剖称量各器官的重量以及计算脏器指数,然后对各器官进行HE染色。结果 ATRA灌胃后,与对照组比较,40 mg/(kg·d) ATRA组肾指数升高,体重变化差异无统计学意义;60 mg/(kg·d) ATRA组体重降低,心、肾指数升高,脾脏重量降低;80 mg/(kg·d)ATRA组体重明显降低,脑、心、肾指数升高,脑、脾重量降低;HE染色显示,与对照组比较,ATRA处理组的肺泡壁增厚,肾小管上皮细胞有空泡样改变,脾脏红髓出现较多巨噬细胞,而大脑、肝脏、心肌无明显组织学变化。结论 体内过量全反式维甲酸能够对生长发育期SD大鼠的肺、肾和脾有一定的损伤作用。     

Influence of zinc supplementation on histopathological changes in the stomach,liver, kidney,brain, pancreas and spleen during subchronic exposure of Wistar rats to glyphosate

A subchronic toxicity study was carried out to determine the glyphosate-induced histopathological changes in the stomach, liver, kidney, brain, pancreas and spleen of rats and the attendant ameliorative effect when pretreated with zinc at the dose rate of 50 mg/kg body weight. The rats were exposed to two doses of the glyphosate (375 and 14.4 mg/kg body weight) for the period of 8 weeks which was the duration of the study, and some groups were exposed to the glyphosate after pretreatment with zinc. The histopathological changes recorded during the study were only in the rats exposed to the glyphosate at the dose rate of 375 mg/kg body weight except the vacuolation encountered in the brains and haemosiderosis in the spleens of rats exposed to zinc alone. Degenerated mucosal epithelial cells which involved the muscularis mucosa and the glands in the stomachs of rats were seen microscopically. Hepatic cells degeneration especially at the portal areas of the livers of rats was observed. The histopathological examination of the kidneys showed glomerular degeneration, mononuclear cells infiltration into the interstices of the tubules and tubular necrosis. The conspicuous changes seen in the brains were neuronal degeneration. Pancreatic acinar cells were degenerated while the spleen of the rats showed depopulated splenic cells in both the red and the white pulps. It was concluded that zinc supplementation in rats prior to glyphosate exposure ameliorated the histopathological changes observed in the stomach, liver, kidney, brain, pancreas and spleen with no observable alteration in the histoarchitecture in the organs of the zinc-supplemented rats.     

Lysosomal-storage disorder induced by elmiron following 90-days gavage administration in rats and mice

Elmiron, a highly sulfated, semisynthetic pentose polysaccharide with properties similar to heparin, is used for the treatment of interstitial cystitis. Thirteen-week gavage studies were conducted by administering the drug in deionized water to F344/N rats and B6C3F1 mice once daily, 5 days per week for up to 13 consecutive weeks, at doses of 0, 63, 125, 250, 500, and 1,000 mg/kg body weight. No significant drug-related effects were observed in body weight, survival, clinical, and necropsy results. Significant organ weight increases were seen in the liver, lungs, and spleen of both species and the kidneys of rats, mainly in groups treated with 250 mg/kg/day and above. Hematological analysis indicated increases for both species in the white blood cell and lymphocyte counts. Sites of toxicity identified histopathologically were the rectum, liver, mesenteric and mandibular lymph nodes (both sexes), spleen (mice only), and lungs and kidneys (rats only). Lesions consisted mainly of infiltration into multiple tissues of vacuolated histiocytes, which, by histochemical investigation, indicated the presence of neutral and acidic mucins and lipidic material within the vacuoles. Transmission electron microscopy identified these vacuoles as lysosomal structures that exhibited a variety of contents. On the basis of our findings, we propose that Elmiron was absorbed through the focally disrupted rectal mucosa, was deposited in the lamina propria, accumulated within macrophages, and then was distributed by these cells or as a free chemical via the lymphatics and blood, to the various organ sites manifesting histiocytic infiltration. The cytoplasmic membrane-bound structures within macrophages were lysosomes containing membranous material of cellular origin and, perhaps, remnants of the deposited test material, Elmiron.     

Experimental analgesic nephropathy: changes in renal structure and urinary concentrating ability in Fischer 344 rats given continuous low doses of aspirin and paracetamol

Long-term treatment with aspirin and paracetamol produced renal papillary necrosis in female Fischer 344 rats. Aspirin (230 mg/kg body weight/day) and paracetamol (380 mg/kg body weight/day) were dissolved in drinking water and given continuously for up to 65 weeks. Renal morphological changes were examined between 21 weeks and 65 weeks of commencement of analgesic treatment using light and electron microscopy, and were compared with age-matched controls. Structural damage initially occurred in the mid-papillary region, and specifically involved the interstitial cells and interstitial matrix. Necrosis of the epithelium of the thin limbs of the loop of Henle was present only after interstitial changes were well established. Cortical interstitial fibrosis and tubular atrophy occurred after renal papillary changes were observed. There was no evidence of significant vascular damage. Urinary concentrating ability was measured sequentially during the period of analgesic treatment. A decrease in urine concentrating ability was present when early changes to the interstitial cells and matrix were observed, and concentrating ability continued to decrease in parallel with increasing morphological damage. This study describes an animal model of analgesic-induced nephropathy, enabling early morphological changes to be studied and correlated with renal functional changes.     

Nephrotoxic tubular and interstitial lesions: morphology and classification

Nephrotoxic renal injury, and especially drug nephrotoxicity is now a common cause of acute renal failure. The most common patterns of renal injury produced by nephrotoxins, tubular damage, and interstitial nephritis, are discussed here. Toxic agents which are primarily tubular toxins include certain antibiotics, cisplatinum, anesthetics, and radiocontrast agents. In tubules injured by toxins, alterations range from subtle ultrastructural abnormalities to extensive tubular necrosis. Mechanisms of tubular injury include direct tubular cell toxicity, and alterations in intrarenal blood flow producing secondary tubular damage. Other commonly used therapeutic agents, including the penicillins, other antibiotics, and non-steroidal anti-inflammatory agents, produce renal dysfunction by inducing interstitial nephritis. Long-term analgesic abuse is associated with a particularly striking interstitial damage with frank papillary necrosis. Criteria for differentiating primary tubular injury with inflammation and primary interstitial nephritis with tubular injury are discussed. Individual commonly-used therapeutic agents are considered in some detail, with discussion of both clinical and morphological aspects of drug nephrotoxicity.     

Acute exposure of uranyl nitrate causes lipid peroxidation and histopathological damage in brain and bone of Wistar rat.

Although the kidneys are the main target organs for uranium (U) toxicity, recent studies have shown that U can cross the blood-brain barrier to accumulate in the brain. Uranyl nitrate (U-238)induced oxidative damage was investigated in brain and bone of Wistar rats after intraperitoneal injection of uranyl nitrate at acute doses either nephrotoxic (576 microg of U/kg body weight) or subnephrotoxic (144 microg U/kg body weight). The health effects of U administration at 576 microg of U/kg body weight were seen in terms of decrease in food intake and no gain in body weight compared to respective controls. These alterations were correlated with increased lipid peroxidation as measured by thiobarbituric acid reactive substances in rat brain and bone. However, at lower dosage of U (144 microg U/kg body weight), no significant lipid peroxidation was observed in brain and bone. Histological examination of U-treated (576 microg of U/kg body weight) rat brain tissues showed marked and diffuse cystic degeneration and a similar pattern in histological alterations was observed in kidneys in treated animals; whereas no significant histological change was observed in rat brains and kidney treated with a lower dose of U (144 microg U/kg body weight). It is concluded that administration of U at an acute nephrotoxic dose caused oxidative stress in brain and bone manifested as lipid peroxidation and histopathological damage.     

Beagle犬药物诱导急性肾损伤模型的研究

目的建立顺铂诱导的Beagle犬急性肾损伤模型,为开展肾毒性生物标志物研究奠定基础。方法通过对Beagle犬单次静脉注射3、4和5 mg/kg顺铂,探讨采用顺铂建立急性肾小管损伤模型的给药方案。密切观察动物给药后临床症状,测定不同时间点的传统血清及尿液新型肾损伤生物标志物的动态变化,在试验结束时解剖动物并进行肾脏组织病理学检查。结果Beagle犬单次静脉注射3 mg/kg顺铂后,临床症状轻微,随后恢复正常。组织病理分析结果显示该动物肾脏发生了损伤病变,包括轻度肾小管变性、坏死或再生;而动物在接受4 mg/kg和5 mg/kg顺铂给药后,动物临床症状严重,并发生濒死和死亡,肾脏也出现了中度肾小管变性、坏死或再生,以及轻度的间质、炎性细胞浸润和肾小管蛋白管型。血清和尿液生物标志物检测结果显示3 mg/kg顺铂给药剂量,动物体内尿素氮和肌酐仅轻微升高,而尿液中丛生蛋白、白蛋白、骨桥蛋白和单核细胞趋化蛋白-1浓度在给药后明显升高,且持续增长。结论Beagle犬单次静脉注射3 mg/kg顺铂可成功构建轻度损伤的急性肾小管损伤模型,为后续在非啮齿类动物中发现早期、灵敏、特异的药物临床前肾毒性生物标志物研究奠定了基础。     

Erysod,erythrocyte superoxide dismutase preparation: effects on LPO processes and morphological changes in the viscera of rats with burns under conditions of delayed antishock infusion therapy

Biochemical and morphological changes in the kidneys, liver, heart, and lungs were studied in rats with deep burns of 20% body surface. Erysod (0.47 mg/kg/day) added to antishock therapy notably reduced the intensity of LPO processes in tissues both in cases when infusion therapy was started immediately (by 8-20% 12 h and by 5-24% 24 h after the injury) and when this therapy was 6 h delayed (by up about 36% after 12 h). This prevented injuries to visceral organs during the acute period of thermal injury and prevented the development of burn disease.     

Cardiovascular alterations in dogs treated with hydralazine

Groups of 5 male beagle dogs were treated orally with hydralazine tablets in gelatin capsules at a dose of 12 or 24 mg/kg twice a day (6 hours apart) for 2 consecutive days. Five male dogs treated with empty gelatin capsules served as untreated controls. Clinical findings and heart rate changes during treatment and terminal body weight, hematology, and blood chemistry changes were evaluated. The heart, liver, kidneys, spleen, and thymus of each animal were examined microscopically. Dogs in the 12 mg/kg group ate less than control group. Dogs treated with 24 mg/kg did not eat and vomited. Heart rates in both of the treated groups increased by 60% to 80% within 2 hours of treatment and remained high during the entire treatment period. Significant hematologic change was confined to a slight increase in platelet number of dogs treated with 24 mg/kg. Serum glucose was increased in the hydralazine treated dogs. Conjugated serum bilirubin was increased and serum potassium, chloride and phosphorus were decreased in the 24 mg/kg group. Blood urea nitrogen and serum chloride were slightly increased in dogs treated with 12 mg/kg. Treatment-related pathologic alterations were confined to the heart. Two dogs from each of the hydralazine groups experienced acute localized hemorrhage into the epicardium and subepicardium of the right atrium. The media of the muscular branches of the coronary arteries, especially the left coronary artery, was hemorrhagic in 3 dogs from the 24 mg/kg group. Medial necrosis, when seen, tended to be proportional to the severity of medial hemorrhages. There was no necrosis in the papillary muscles of the heart.(ABSTRACT TRUNCATED AT 250 WORDS)     

Methanolic effect of Clerodendrum myricoides root extract on blood,liver and kidney tissues of mice

The present study deals with the toxicological investigations of chronic treatment with methanol root extract of Clerodendrum myricoides on body weight, hematological and biochemical parameters, and liver and kidney tissue sections. Mice treated with 100mg/kg bw/day of methanol extract showed no behavioral changes. However, there was a general reduction of activity in mice treated with 400mg/kg bw/day methanol extract and LD₅₀ treated mice showed hypoactivity, grooming, prostration, piloroerection and irritation during administration towards the last days of the treatment period. The body weight gain difference in the 100mg/kg bw/day methanol extract treated group was not significant, while those of the others were significant as compared with the controls. Hematological results for the RBC count, HCT, MCV, MCH and MCHC in methanol extract treated mice showed no significant changes at both doses of treatments as compared with the controls. However, the value of lymphocytes was found significantly increased at 100 and 400mg/kg bw/day methanol extract. Similarly, HGB was significantly increased at 100 and 400mg/kg bw/day of methanol extract treated groups. On the other hand, WBC and platelets count were significantly decreased after treatment with 400mg/kg bw/day methanol extract. ALT, ALP, AST and urea values were significantly increased respectively at 100mg/kg bw/day and 400mg/kg bw/day methanol extract. Several histopathological changes of liver and kidney were observed in the extract treated mice as compared to the controls. Such histopathological changes observed in both liver and kidneys were inflammations and hydropic degenerations of hepatocytes at both doses of methanol. In addition, in the LD₅₀ treated mice of the extracts there were also hemorrhages and signs in congestion of glomeruli of the kidney.

Conclusion

chronic treatment with Clerodendrum myricoides extracts in mice causes reduction in body weight gain, damage to liver & kidney and changes in some hematological & biochemical parameters. It is therefore, suggested that further studies are needed for minimization of the observed side effects, while maintaining the claimed medicinal values of the extract.     

Acute and subacute toxicity study of 1,8-cineole in mice

The effects of acute and subacute toxicity of 1,8-cineole in Kunming mice were studied. After acute oral administration, the LD₅₀ value (95% CL) was 3849 mg/kg (3488.8~4247.1 mg/kg). In the subacute toxicity study, there were no significant differences in body weight and relative organ weight between the control group and 1,8-cineole treatment groups. The histopathological examinations showed that granular degeneration and vacuolar degeneration appeared in liver and kidney tissue after administration of high dose of 1,8-cineole. Under electron microscopy, a series of ultrastructural changes were observed: The electron microscopy assays indicated that the influence of 1,8-cineole on the target organ at the subcellular level were mainly on the mitochondria, endoplasmic reticulum and other membrane type structure of liver and kidney.     

Tobramycin-induced changes in renal histology of fetal and newborn Sprague-Dawley rats.

Effects on renal development were studied using tobramycin (TBM) as a model compound. Pregnant Sprague-Dawley rats were injected i.p. with TBM at 30 or 60 mg/kg body weight/day on gestational days (GD) 10-19. Kidneys from dams and conceptuses were examined on GD 20 and on postnatal day (PD) 9. The dosing regimen caused in dams moderate proximal tubular alterations and increased concentrations in serum creatinine. Fetal kidneys showed granularity and swelling of proximal tubule cells at the 30 mg/kg dose, poor glomerular differentiation at the 60 mg/kg dose, increased glomerular density at both doses, and no changes on macroscopic examination at either dose. In newborns were observed a moderate developmental delay and tubular lesions at the higher dose, and dose-related increases of glomerular density and relative medullary area at both doses. All findings were more pronounced in males. A maturational disruption of the tubular structures possibly leading to increased glomerular density was attributed to TBM exposure during renal organogenesis in the rat.     

The effects of high-fat diet on the renal structure and morphometric parametric of kidneys in rats

To characterize the kidney in a high-fat-induced obesity model, we examined the renal structure of adult Sprague-Dawley rats fed a control diet or a high-fat diet for 3 months. Ten adult female Sprague-Dawley rats were fed a diet consisting highly of fat (30%) for a period of 3 months. Ten control rats were maintained with standard rat chow. All animals were weighed every 10 days for 3 months. At the end of the experiment, the naso-anal length of the anaesthetized rats was measured to calculate body mass index, and subsequently whole kidneys of intracardially formalin-perfused animals were removed. Quantitative features of the kidney were analysed with the Cavalieri and physical dissector methods applied to serial paraffin sections. Kidney samples were also examined histologically. The body mass indices of the control and treatment groups were 4.528 +/- 0.242 and 5.876 +/- 0.318 kg m(-2), respectively. The difference between the body mass indices of the two groups was statistically significant (P < 0.01, Mann-Whitney U-test), suggesting that the animals fed with a high-fat diet may be overweight. Stereological examination of the kidneys revealed differences in kidney weight, total kidney volume, volume of cortex, medulla, glomeruli, proximal and distal tubules, and numerical density of glomeruli and glomerular height in the treatment group compared with the control group. Light microscopic investigation showed a dilatation in blood vessels and Bowman's space, mononuclear cell infiltration, degeneration in nephrons, including glomerulosclerosis and tubular defects, and an increase in the connective tissue in the kidneys in the treatment group. We concluded that a fatty diet is responsible for the rats' obesity and may lead to renal deformities as a result of histopathological changes such as dilatation, tubular defects, inflammation and connective tissue enlargement of the kidney.     

Time and dose-response study of the effects of vanadate on rats: morphological and biochemical changes in organs

Vanadate at a dosage level of 0.9 mg V/kg per day produced acute toxic signs in rats when injected subcutaneously for 16 days. These signs were weakness, loss of appetite, dehydration, significant reduction in body weight, nose bleeding, and death. The pathological and biochemical changes were most severe in kidney tissue. The kidney lesions were bilateral and multifocal. At two days, degenerative and necrotic changes of the tubular and glomerular epithelium, thickening of glomerular membrane, vascular congestion, and edema were observed. At five days, proliferation of tubular epithelial and interstitial cells was observed. At 12 days, the cellular proliferation in both cortex and medulla was significantly greater. Fibrosis was observed at glomerular tuft, preglomeruli, pretubules, and interstitium (cortex and medulla). At 25 days, the collagen deposition reached the highest level in all regions, cellular proliferation decreased, and thickening of the arteriolar wall became prominent. The renal lesions were coupled with changes in the levels of protein, RNA, DNA, and hydroxyproline. At 40 days, the kidney showed signs of recovery. Blood urea nitrogen levels were significantly elevated at 2-25 days post-treatment. Stained tissue sections from liver, lung, heart, spleen, thymus, lymph nodes, testes, and adrenal glands of the treated rats were examined microscopically and appeared normal. Biochemically, significant changes (p less than .05) in protein, RNA, DNA, and hydroxyproline were also observed in these organs. At lower dosage (0.6 mg V/kg per day for 16 days), similar but less severe pathological and biochemical changes in kidneys and other organs were observed. At 0.3 mg V/kg per day for 16 days, the changes in the tissues were detected only at the biochemical level. These results indicate that the toxic effects of vanadium are cumulative and that vanadium-produced fibrosis in tissues is dose-dependent.     

Postmortem pathology of opportunistic infection in a HIV positive patient--a case report

An autopsy case of HIV positive patient with multiple opportunistic infections is described. We received heart, lungs, spleen and both the kidneys along with pieces of cerebrum for anatomy and histopathological examination. Histology of organs revealed disseminated non-granulomatous necrotizing type of tissue reaction with superadded infection with Cryptococcus neoformans (C. neoformans) in liver and brain. Pneumocysts carini (P. carini) induced pneumonia in lungs, disseminated mycobacterial infection in spleen, lungs, liver and kidneys and acute fibrinous meningitis with superadded infection with C. neoformans in brain. Special stains were carried out to demonstrate different organisms.     

Ultrastructural morphology of acute alcoholic intoxication

Histologic and electron-microscopic examination of the liver, heart, kidneys, lungs of 32 individuals who died from acute alcoholic intoxication (alcoholemia from 2,9 to 7,2 0/00) and 16 people who died suddenly from a trauma being in the state of a severe alcoholic intoxication. Material was taken for the examination within 3 hours after death. The ultrastructural alterations detected in the organs reflect a deep metabolic disturbances resulting from an acute or chronic alcoholic intoxication. The relation of morphological changes with an age and an alcohol abuse duration is discussed.     

Histological alterations in the testicular tissue induced by sildenafil overdoses

Twenty adult male rabbits (Oryctolagus cuniculus) received sildenafil (0, 1, 3, 6, 9 mg/kg/day) for 4 weeks to investigate the testicular histological alterations induced by overdoses of this drug. Exposure to overdoses of sildenafil had provoked tubular and interstitial histological alterations. Abnormality in the germinal epithelium of the seminiferous tubules included spermatocytes karyopyknosis, spermatocytes degeneration, desquamation, spermatid giant cells and arrest of spermatogenesis. Additionally, increased Leydig cells cellularity, tubular degeneration, thickening of the interstitium were also observed. The encountered histological findings indicate that chronic exposure to sildenafil overdoses produces significant morphological and histological alterations in the testes which finally might lead to complete arrest of spermatogenesis.     

A study on the morbid histopathological changes in COVID-19 patients with or without comorbidities using minimally invasive tissue sampling

COVID-19 causes morbid pathological changes in different organs including lungs, kidneys, liver, and so on, especially in those who succumb. Though clinical outcomes in those with comorbidities are known to be different from those without—not much is known about the differences at the histopathological level. To compare the morbid histopathological changes in COVID-19 patients between those who were immunocompromised (Gr 1), had a malignancy (Gr 2), or had cardiometabolic conditions (hypertension, diabetes, or coronary artery disease) (Gr 3), postmortem tissue sampling (minimally invasive tissue sampling [MITS]) was done from the lungs, kidney, heart, and liver using a biopsy gun within 2 hours of death. Routine (hematoxylin and eosin) and special staining (acid fast bacilli, silver methanamine, periodic acid schiff) was done besides immunohistochemistry. A total of 100 patients underwent MITS and data of 92 patients were included (immunocompromised: 27, malignancy: 18, cardiometabolic conditions: 71). In lung histopathology, capillary congestion was more in those with malignancy, while others like diffuse alveolar damage, microthrombi, pneumocyte hyperplasia, and so on, were equally distributed. In liver histopathology, architectural distortion was significantly different in immunocompromised; while steatosis, portal inflammation, Kupffer cell hypertrophy, and confluent necrosis were equally distributed. There was a trend towards higher acute tubular injury in those with cardiometabolic conditions as compared to the other groups. No significant histopathological difference in the heart was discerned. Certain histopathological features were markedly different in different groups (Gr 1, 2, and 3) of COVID-19 patients with fatal outcomes.