Acute and Sub-Acute Toxicity Evaluation of the Crude Methanolic Extract of Justicia schimperiana Leaf in Wistar Albino Rats

Purpose

This study evaluates the acute and sub-acute toxicity of 80% methanolic extracts of the leaves of Justicia schimperiana in Wistar albino rat models.

Methods

Dried powdered leaves of Justicia schimperiana were macerated in 80% methanol. The experiment was conducted in accordance with the Organization for Economic Co-operation and Development guideline 423 for acute and 407 for sub-acute toxicity testing. A single dose of 5000 mg/kg extract was orally administered to three female rats for the acute toxicity study. The plant extract was administered orally for 28 days in daily dosages of 250, 500, and 1000 mg/kg for the sub-acute study. Animals in a control group were given distilled water. A total of 40 rats (5 rats/group/sex) were used for the sub-acute toxicity testing. Daily food intake and weekly body weight measurements were done. The rats were sacrificed at the end of the 28-day treatment period for hematological, biochemical, and histopathological tests. One-way analysis of variance and Kruskal-Wallis tests were employed for the analysis.

Results

The single-dose oral administration of the plant resulted in no deaths or serious morbidity. The median lethal dose was >5000 mg/kg. The 28-day oral treatment of the plant extract had no significant effect on general behavior, food intake, organ weight, biochemical parameters, or the majority of the hematological markers, with the exception of the decrease in hemoglobin and hematocrit in the 1000 mg/kg extract-treated groups compared to the controls. Both sexes experienced significant weight increases at all dosage levels. With the exception of minor alterations in a few of the organs, no significant histological change was identified.

Conclusion

It is concluded that the single-dose and repeated-dose 28-day oral administration of the methanolic leaf extract of Justicia schimperiana is relatively safe.

Acute and sub-acute toxicity study reveals no dentrimental effect of formononetin in mice upon repeated i.p. dosing

AIM

Formononetin is a phytoestrogen which possess different pharmacological activities. The intraperitoneal route permits the identification of target organs involved in toxicity without compromising the molecule's bioavailability. The current study investigated the safety profile of intraperitoneal formononetin in Swiss albino mice.

MATERIAL AND METHODS

For acute toxicity study, formononetin administered intraperitoneally to mice at the doses of 5, 50, 100, 150, 200, and 300 mg/kg for 14 days. For the subacute toxicity study, mice were intraperitoneally administered with formononetin (12.5, 25, and 50 mg/kg) daily for 28 days.

RESULTS

During the acute study, no deteriorating effect was observed on body weight, food and water intake, no behavioral changes were observed in animals. The lethal dose 50% (LD50) of formononetin was determined to be 103.6 mg/kg of BW, with a no observed adverse effect level (NOAEL) of 50 mg/kg of BW. Mortality was observed in the 300 mg/kg dose group and histopathological changes such as a mild degree of diffuse granular degeneration in the liver but for rest all doses did not have any adverse effect. In subacute study, no signs of adverse effects, mortality, no changes in body weight, food and water intake, and hematological and biochemical parameters were observed. Histopathology of subacute study indicates, formononetin did not have any noxious effect on organs.

CONCLUSION

Formononetin shows mortality at acute dose 300 mg/kg and LD50 at 103.6 mg/kg of BW, with a NOAEL of 50 mg/kg of BW, rest all doses for acute and sub-acute are safe when given intraperitoneally.

Quercetin and Ferulic Acid Elicit Estrogenic Activities In Vivo and In Silico

In this study, we examined the sub-acute toxicity of quercetin and ferulic acid and evaluated their effects on protein, cholesterol, and estrogen levels in vivo. Six groups of female Wistar rats were fed by gavage. The first and second groups represent the positive (Clomiphene citrate 10 mg/kg) and negative (NaCl 0.9%) control groups, while the other groups received quercetin and ferulic acid at doses of 5 and 10 mg/kg/day for 28 days. The sub-acute toxicity was monitored by examining the weights, biochemical parameters (AST, ALT, ALP, urea, and CREA), and histological changes in the kidneys and liver of the treated animals. Furthermore, the in vivo estrogenic effects were studied in terms of the serum and ovarian cholesterol levels, serum estradiol, and uterine proteins. Finally, Docking studies were conducted to evaluate the binding affinity of quercetin and ferulic acid for alpha and beta estrogen receptors. Results showed that both compounds were devoid of any signs of nephrotoxicity or hepatotoxicity. Additionally, quercetin and ferulic acid caused significant estrogenic effects evidenced by an increase of 8.7 to 22.48% in serum estradiol, though to a lesser amount than in the reference drug-treated group (64.21%). Moreover, the two compounds decreased the serum cholesterol levels (12.26-32.75%) as well as the ovarian cholesterol level (11.9% to 41.50%) compared to the negative control. The molecular docking in estrogen alpha and estrogen beta active sites showed high affinity of quercetin (-10.444 kcal/mol for estrogen alpha and -10.662 kcal/mol for estrogen beta) and ferulic acid (-6.377 kcal/mol for estrogen alpha and -6.3 kcal/mol for estrogen beta) to these receptors. This study provides promising insights into the potential use of quercetin as a therapeutic agent for the management of female fertility issues.

The sub-acute toxicity of kavalactone in rats: a study of the effect of oral doses and the mechanism of toxicity in combination with ethanol

Kava is a herbal supplement and beverage made from the Piper methysticum plant, which is known for its recreational use as a mood enhancer, relaxation, as well as pain relief for centuries. Kava is widely used among alcoholics, but it is dangerous and potentially fatal. The objectives of this study were to examine the sub-acute toxicity effects of different doses of 70% kavalactone (KL) in rats by oral application, as well as to elucidate the mechanisms of toxicity alone and in combination with ethanol (EtOH). The most common side effects observed were abnormal breathing, ataxia, lethargy, loss of appetite, indigestion, and loss of coordination, especially in the 800 mg/kg bw, po bodyweight dosage of kava treatment group alone, and in combination with EtOH. In the sub-acute study, there were dose-related decreases in body weight, feed intake, and water consumption rates. Gross and histopathological findings revealed that the liver was abnormal in color, size, consistency, and the weight significantly increased at a dose of 800 mg/kg bw, po, with KL alone and a greater increase in combination with EtOH. Hepatocellular hypertrophy (HP) and necrosis with Kupffer cells hyperplasia were observed in the periacinar zone of all rats dosed with KL (800 mg/kg bw, po) alone, and extensive changes were observed in combination with EtOH. The periportal (Z1) and mid-zonal (Z2) areas of hepatocytes were less affected as compared to the periacinar zone. These results demonstrate that EtOH exacerbated the sedative and hypnotic activity of KL, and markedly increased toxicity. The histopathological results supported the clinical and biochemical findings and the severity of hepatic damage in a dose-dependent manner.

Phytochemical analysis, in silico study and toxicity profile of Cycas pectinata Buch.-Ham seed in mice

Fruit of Cycas pectinata Buch.-Ham has been used as medicine by the local community in some parts of the north eastern state of India. Despite its uses for different purposes, the safety assessment study has not been conducted. Therefore, we have evaluated the acute and the sub-acute toxicity of methanolic extract of C. pectinata fruit (CPFE) in a mice model via oral route of administration. Phytochemicals analysis was carried out by liquid chromatography-mass spectroscopy (LC-MS), nuclear magnetic resonance (NMR), and Fourier-transform infrared spectroscopy (FTIR). The acute toxicity study was performed at a single dose of 1000, 3000 and 5000 mg/kg and the sub-acute toxicity study at a dose of 100, 300 and 500 mg/kg was administered daily for 28 days. The calculated Lethal dose 50 (LD50) of CPFE was found to be 4000 mg/kg. Both acute and sub-acute studies showed that 5000 mg/kg and 500 mg/kg dose was toxic to the mice. The results of acute toxicity showed CPFE could have a mild toxic effect on the kidney at a dose of 3000 and 5000 mg/kg, as some deteriorated changes in the kidney along with increase creatinine levels were observed. Acute toxicity also showed an increase in white blood cells (WBC) at a dose of 3000 mg/kg.However, sub-acute toxicity studies do not show any detrimental effects on liver, kidney and hematological parameters. Thus, it can be suggested that CPFE at a dose of 100 and 300 mg/kg would be safe for consumption. The phytochemicals analysis by LC-MS, NMR and FTIR showed the presence of 32 major chemical compounds with certain biological activity like anti-neoplastic, antioxidant, and possible modulator of steroid metabolism (cholesterol antagonist and agonist of testosterone 17β-dehydrogenase) as predicted by PASS analysis.

Acute and sub-acute toxicity study of ethanol extract from Nectandra leucantha Nees & Mart. (Lauraceae) barks

Nectandra leucantha has been used in traditional medicine. Several metabolites isolated from N. leucantha extracts displayed immunomodulatory, antileishmanial properties, but the determination of the toxicological profile in mammals has not previously been performed. In this study, the ethanol extract from N. leucantha barks (EENl) was characterized by HPLC/HRESIMS. To study acute toxicity, female mice received EENl in a single dose of 100, 300, 1000, or 2000 mg/kg bw. Later, sub-acute toxicity was introduced in female and male mice by oral gavage at 100, 500 or 1000 mg/kg bw for 28 consecutive days. Hematological and biochemical profiles from the blood as well as histological analysis from the liver and kidney were performed. The HPLC/HRESIMS analysis of the EENl revealed the presence of six neolignans chemically related to dehydrodieugenol B. In the oral acute and sub-chronic studies, EENl did not produce in all doses evaluated any alteration in behavior, biochemical, hematological, body weight gain and food intake or sudden death in Swiss mice. In addition, histopathological data did not reveal any disturbance in liver and kidney morphology after 28 days of EENl treatment. Our results indicate that EENl at dosage levels up to 2000 mg/kg bw is non-toxic and can be considered safe for mammals.

Safety assessment of Bauhinia cheilantha Bong. Steud leaves extract: acute, sub-acute toxicity, antioxidant, and antihemolytic evaluations

Bauhinia cheilantha (Fabaceae), known popularly as pata-de-vaca and mororó has been largely recommended treating several diseases in folk medicine. However, information on safe doses and use is still scarce. The goal was to evaluate in-vitro antioxidant and antihemolytic and also acute and sub-acute toxicity effects of hydroalcoholic extract from B. cheilantha leaves (HaEBcl). The identification of the compounds in the HaEBcl was performed by ultra-performance liquid chromatography coupled with a diode array detector and quadrupole time-of-flight mass spectrometry. Antioxidant and hemolytic activity of HaEBcl was evaluated in vitro. To study acute toxicity, female mice received HaEBcl in a single dose of 300 and 2.000 mg/kg. Later, sub-acute toxicity was introduced in both female and male mice by oral gavage at 300, 1000, or 2000 mg/kg for 28 consecutive days. Hematological and biochemical profiles were created from the blood as well as from histological analysis of the liver. HaEBcl is rich in flavonoids (quercitrin and afzelin), has no hemolytic effects and moderate antioxidant effects in vitro. Acute toxicity evaluation showed that lethal dose (LD₅₀) of HaEBcl was over 2000 mg/kg. Sub-acute toxicity testing elicited no clinical signs of toxicity, morbidity, or mortality. The hematological and biochemical parameters discounted any chance of hepatic or kidney toxicity. Furthermore, histopathological data did not reveal any disturbance in liver morphology in treated mice. Results indicate that HaEBcl has no hemolytic and moderate antioxidant effects in vitro. In addition, HaEBcl dosage levels up to 2000 mg/kg are nontoxic and can be considered safe for mammals.

Oral toxicity evaluation of gokshuradi guggulu, an ayurvedic formulation

Gokshuradi guggulu is an important classical polyherbal formulation used in Ayurvedic system of medicine for the treatment of various chronic diseases like kidney stones and diabetes. However, no scientific attempts were made to evaluate its oral toxicity. Hence, the present study evaluated the acute and 28 days repeated dose sub-acute oral toxicities of gokshuradi guggulu in rats. Gokshuradi guggulu was tested for its compliance using physicochemical and analytical parameters as per standards prescribed in Ayurvedic Pharmacopeia of India. In acute oral toxicity study, Wistar rats were orally administered a single dose of gokshuradi guggulu (2700 mg/kg) and clinical signs and mortality or moribund stage were observed for 14 days along with weekly body weight. On day 15, the rats were euthanized and the gross morphology was carried out during necropsy. In sub-acute (repeated dose) oral toxicity study, the rats were orally administered gokshuradi guggulu (270, 1350 and 2700 mg/kg) once daily up to 28 days. Clinical signs and mortality or moribund stage, weekly body weight, weekly feed and water consumptions, biochemical and hematological investigations, urine analysis, and major organ weights and histopathology were carried out. In acute and sub-acute toxicity studies, gokshuradi guggulu administration did not show any alteration in parameters or any adverse effect as compared to vehicle treated group. There was no mortality or moribund state observed in any group in both studies. Administration of gokshuradi guggulu in acute and 28 days repeated doses did not exhibit any toxicity or adverse effect at the doses used and NOAEL was found to be 2700 mg/kg.

Sub-acute Toxicity Assessment of Taxol Isolated From Fusarium Solani, an Endophytic Fungus of Taxus Brevifolia, in Wistar Rats and Analyzing Its Cytotoxicity and Apoptotic Potential in Lung Cancer Cells

The limited availability of taxol from plant sources has prompted the scientific world to look for an alternative, as in the chemical synthesis of tissue cultures of the Taxus species, to meet the increasing demand for the drug. However, these alternative means are expensive or result in low yield. Previously, we have reported that Fusarium solani isolated from Taxus celebica produced taxol and its precursor baccatin III in liquid-grown cultures, and it exhibited promising anticancerous effects in certain cancer cell lines. In the present study, we examined the sub-acute toxicity of fungal taxol (FS) in Wistar rats according to the Organization for Economic Co-operation and Development (OECD) guidelines. The sub-acute oral administration of FS up to 500 mg/kg for a period of 28 days appears to be safe in rats and did not cause severe treatment-related toxicity or treatment-related death. The observed changes in body weight, histopathology, hematological and biochemical parameters, and organ weight were not significant compared to those in the control group of animals. The results suggest that FS is relatively safe when administered orally in rats. The antiproliferative and apoptosis-inducing activities were studied in A549 (human lung cancer) cell line. FS arrested the cells at S and G2/M phases, leading to apoptosis. The characteristic molecular signatures of apoptosis, such as externalized phosphatidyl serine, DNA fragmentation, and nuclear and chromatin condensation, were observed upon FS treatment. FS triggered the generation of reactive oxygen species in A549 cells and elicited cell death by both extrinsic as well as the mitochondria-mediated intrinsic pathway of apoptosis. These results indicate that endophytic fungi isolated from medicinal plants may serve as potential sources of anticancerous compounds with little side effects.

Acute and Subacute Toxicity Study of Graphene-Based Tumor Cell Nucleus-Targeting Fluorescent Nanoprobes

Graphene-based tumor cell nuclear targeting fluorescent nanoprobes (GTTNs) were synthesized in our laboratory as a kind of nanomaterial and showed good performance for both in vivo and in vitro imaging. GTTNs directly cross the cell membrane and specifically target the tumor cell nucleus via a cell membrane permeability targeting (CMPT) mechanism, which takes advantage of the increased permeability of the tumor cell membranes. GTTNs with a CMPT mechanism achieve high targeting efficiency in tumor tissues. With the tumor cell nucleus-targeting characterization, the GTTN distinguishes tumor cells at the single-cell level and recognizes the tumor tissue interface in a very early stage and shows great potential in clinical applications. Toxicity studies are extremely critical for clinical applications. Therefore, we studied the acute and subacute toxicity of GTTNs using an in vivo method and examined the following experimental indicators: mouse body weight, organ coefficients, serum biochemical parameters, and histological changes. The results showed that there were no significant differences in any indicators between the experimental and control mice. We also used an in vitro method to study the cytotoxicity of GTTNs in GES-1 (gastric epithelial cell) cells. Surprisingly, the results demonstrated over 80% cell viability when the incubation time reached up to 72 h under a 200 mg/L concentration of GTTNs, which indicated that GTTNs had low cytotoxicity. GTTNs barely showed any acute or subacute toxicity or cytotoxicity in vivo and in vitro, respectively, which supports their use for clinical applications.

Biochemical and histopathological effects of sub-acute exposure of albino rats to fumigants - dichlorvos and cypermethrin

Cypermethrin (CYP) is one of the most common active ingredients in most insecticides, mosquito coils and powder used in Nigeria. dichlorvos (DDVP) is the most indiscriminately used fumigant in most rural and sub-urban areas in Nigeria. These fumigants can easily be accessed without proper method of usage thus exposing the population to their toxic effects. As a result, this study was initiated to determine the effects of sub-acute exposure of CYP and DDVP on some biochemical and histopathological parameters of albino rats. In this study, forty (40) albino rats of 10 groups of 4 rats per group, with one group serving as control, were exposed to these fumigants in a poorly ventilated area for 4hours per day over 2, 4 and 6 weeks. The results showed observable changes in liver enzyme activities (p<0.05) in groups exposed to DDVP for 2, 4 and 6 weeks. The groups exposed to CYP showed mild changes in liver enzyme activities when compared with the DDVP groups. Increase in activity of the liver enzymes was also observed in the groups exposed to a mixture of DDVP+CYP for 2, 4 and 6 weeks. The urea, creatinine and electrolytes levels in all the groups exposed to DDVP, CYP and DDVP+CYP for 2, 4 and 6weeks were significantly (p<0.05) increased. Also WBC and platelets in all the groups exposed to DDVP and CYP recorded significant changes. The histology report of the lungs and liver showed moderate lymphocytic infiltration and hepatocytic steatosis which progressed with duration of exposure to the fumigants, while the kidneys showed no remarkable changes. The results of this study suggest that DDVP and CYP have relative toxic effects in the exposed animals and should be used with caution to avoid human exposure to their visible toxicities.

Diligent profiling of preclinical safety of the silk protein sericin

BACKGROUND

Sericin is a widely used protein in the pharmaceutical industry derived from the silkworm, Bombyx mori, and used for the treatment of various diseases and pathological conditions. It is the main ingredient of the Unani preparation khameera abresham. The study was conducted to evaluate the preclinical toxicity of the silk protein sericin in mice.

METHODS

In the acute toxicity study, sericin was administered once orally to different groups of animals at doses of 500, 1000, and 2000 mg/kg. Animals were observed for 14 days. In the sub-acute toxicity study, sericin was administered in mice for 4 weeks in the toxic group at doses of 500, 1000, and 2000 mg/kg, while in the recovery group it was administered for 4 weeks at doses of 500 and 2000 mg/kg followed by 2 weeks of distilled water administration.

RESULTS

In the acute toxicity study, the observed parameters showed no significant difference, and no mortality was reported. In the sub-acute toxicity study, there were no toxicological effects in any of the estimated parameters, while histopathological analysis showed inflammation in vital organs at the dose of 2000 mg/kg.

CONCLUSIONS

Results of our acute toxicity study suggest that sericin is safe at all administered doses, while the sub-acute study suggests that the NOAEL (no-observed-adverse-effect level) of sericin is below 2000 mg/kg, at which it can be considered safe.

Oxidative damage mediated iNOS and UCP-2 upregulation in rat brain after sub-acute cyanide exposure: dose and time-dependent effects

Cyanide-induced chemical hypoxia is responsible for pronounced oxidative damage in the central nervous system. The disruption of mitochondrial oxidative metabolism has been associated with upregulation of uncoupling proteins (UCPs). The present study addresses the dose- and time-dependent effect of sub-acute cyanide exposure on various non-enzymatic and enzymatic oxidative stress markers and their correlation with inducible-nitric oxide synthase (iNOS) and uncoupling protein-2 (UCP-2) expression. Animals received (oral) triple distilled water (vehicle control), 0.25 LD50 potassium cyanide (KCN) or 0.50 LD50 KCN daily for 21 d. Animals were sacrificed on 7, 14 and 21 d post-exposure to measure serum cyanide and nitrite, and brain malondialdehyde (MDA), reduced glutathione (GSH), glutathione disulfide (GSSG), cytochrome c oxidase (CCO), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR) and catalase (CA) levels, together with iNOS and UCP-2 expression, and DNA damage. The study revealed that a dose- and time-dependent increase in cyanide concentration was accompanied by corresponding CCO inhibition and elevated MDA levels. Decrease in GSH levels was not followed by reciprocal change in GSSG levels. Diminution of SOD, GPx, GR and CA activity was congruent with elevated nitrite levels and upregulation of iNOS and UCP-2 expression, without any DNA damage. It was concluded that long-term cyanide exposure caused oxidative stress, accompanied by upregulation of iNOS. The upregulation of UCP-2 further sensitized the cells to cyanide and accentuated the oxidative stress, which was independent of DNA damage.

Alterations in morphology and hepatorenal indices in rats subacutely exposed to bitumen extract

Bitumen is a complex mixture of dense and extremely viscous organic liquids produced by distillation of crude oil during petroleum refining. Nigeria has a large deposit of natural bitumen, yet to be fully exploited. Discharges of petroleum hydrocarbons and other petroleum-derived products have caused environmental pollution and adverse human health effects in several oil-rich communities. In this study, bitumen obtained from a seepage source in Agbabu, the town of first discovery, was used in sub-acute toxicity studies in a rat experimental model, in order to assess potential health risks posed to local populace sequel to full exploitation of bitumen. Dosages were chosen to accommodate low to high cases of environmental exposures. Male Wistar rats were administered, per os, dosages of bitumen extract at 5, 3, 2, and 1 mg/kg body weight. Following euthanasia 28 days later, histological findings revealed severe portal congestion and cellular infiltration in the liver, while in the kidney there were protein casts in the tubular lumen. The relative liver and kidney weights in the 5 mg/kg groups were 34% and 40% higher than in the controls, with a concomitant decrease in food and water consumption. Furthermore, plasma clinical analyses revealed marked elevation in aspartate aminotransferase and triglycerides levels in bitumen extract-intoxicated rats. The results indicate the potential hepatorenal toxicity in adult rats following repeated exposure to bitumen extract.

Toxicity and Safety Profiles of Methanolic Extract of Pistacia integerrima J. L. Stewart ex Brandis (PI) for Wistar Rats

Objectives:

The goals of this research were to evaluate acute (single-dose) and sub-acute (repeated-dose) toxicity profiles of methanolic extract of Pistacia integerrima J. L. Stewart ex Brandis (PI) for Wistar rats and to assess the safety profile of PI by observing physiological changes, mortality, changes in body weight, the histopathology of body organs, the hematology and the biochemistry of the animals.

Methods:

The toxicity profile of PI was evaluated using Wistar rats of both sexes. Animals were divided into four groups: Group 1; control group (normal saline), Group 2; PI-1 (250 mg/kg), Group 3; PI-2 (500 mg/kg), Group 4; PL-3 (1,000 mg/kg). An acute-toxicity study in which animals received a single dose of PI extract (2,000 mg/ kg) and were then observed for 14 days for changes in skin, fur, eye color, mucous membrane secretions and excretions, gait, posture, and tonic or clonic movements was performed according to guideline 425 of the Organization of Economic and Corporation Development (OECD). In the repeated-dose toxicity study (OECD – 407) animals received a daily dose of PI extract for 28 days (4 weeks). The parameters observed in this study include body weight, hematology and biochemistry of the animals.

Results:

In the acute toxicity study, no mortalities or changes in behavior were noted in the animals. The repeated-dose toxicity study was also devoid of any toxicity in the animals during the 28 days of testing with PI extract. The extract did not alter- the body weight, hematology or biochemistry of the animals. The methanolic extract of PI was to be found safe to the no-observed-adverse-effect-level (NOAEL) for the single- dose and repeated-dose toxicity tests in rats.

Conclusion:

The methanolic extract of PI was devoid of toxicity; hence, it can be used for various ayurvedic preparations and treatments of diseases.

Sub-Acute Toxicity Study of Tiger Milk Mushroom Lignosus tigris Chon S. Tan Cultivar E Sclerotium in Sprague Dawley Rats

Lignosus also known as “Tiger Milk Mushroom,” is classified in the family Polyporaceae and mainly consumed for its medicinal properties in Southeast Asia and China. The sclerotium is known as the part with medicinal value and often used by the natives to treat a variety of ailments. Lignosus tigris Chon S. Tan, one of the species of the Malaysia Tiger Milk mushroom, has recently been successfully cultivated in laboratory. Earlier studies have demonstrated the L. tigris cultivar E sclerotia exhibited beneficial biomedicinal properties. This study evaluated the potential toxicity of L. tigris E sclerotia in a 28-day sub-acute oral administration in Sprague Dawley (SD) rats. L. tigris E sclerotial powder was administered orally at three different doses of 250, 500, and 1000 mg/kg to the SD rats once daily, consecutively for 28-days. Body weight of the rats was recorded and general behavior, adverse effects, and mortality were observed daily throughout the experimental period. At the end of the experiment, blood hematology and biochemistry, relative organ weights, and histopathological analysis were performed. Results showed that there were no mortality nor signs of toxicity throughout the 28-day sub-acute toxicity study. Oral administration of the L. tigris E sclerotial powder at daily dose up to 1000 mg/kg had no significant effects in body weight, relative organ weight, blood hematological and biochemistry, gross pathology, and histopathology of the organs. L. tigris E sclerotial powder did not cause any treatment-related adverse effect in the rats at different treatment dosages up to 1000 mg/kg. As the lethal dose for the rats is above 1000 mg/kg, the no-observed-adverse-effect level (NOAEL) dose is more than 1000 mg/kg.

Toxicological studies of aqueous extract of Acacia nilotica root

Acacia nilotica is a widely used plant in traditional medical practice in Northern Nigeria and many African countries. The aim of this study was to determine the toxicological effects of a single dose (acute) and of repeated doses (sub-acute) administration of aqueous extract of A. nilotica root in rodents, following our earlier study on antiplasmodial activity. In the acute toxicity test, three groups of Swiss albino mice were orally administered aqueous extract of A. nilotica (50, 300 and 2000 mg/kg body weight) and signs of toxicity were observed daily for 14 days. In the sub-acute toxicity study, four groups of 12 rats (6 male and 6 female) were used. Group 1 received 10 ml/kg b.w distilled water (control), while groups 2, 3 and 4 received 125, 250 and 500 mg/kg b.w of the extract, respectively, for 28 consecutive days by oral gavage. Signs of toxicity/mortality, food and water intake and body weight changes were observed. Biochemical parameters were analysed in both plasma and liver homogenate. In the acute and sub-acute toxicity studies, the extract did not cause mortality. A significant reduction in the activity of lactate dehydrogenase was observed at 250 and 500 mg/kg b.w, while alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase activities were significantly higher than control values at 500 mg/kg b.w. The aqueous extract of A. nilotica was found to be safe in single dose administration in mice but repeated administration of doses higher than 250 mg/kg b.w of the extract for 28 days in rats may cause hepatotoxicity.

Comparative toxicity profiles of Plumbago zeylanica L. root petroleum ether, acetone and hydroalcoholic extracts in Wistar rats

Introduction:

The root of Plumbago zeylanica Linn. is used in traditional medicine for the treatment of chronic inflammatory diseases and various disorders. The toxicity of this plant has not yet been extensively evaluated.

Aim:

To evaluate and compare the toxicity of P. zeylanica root petroleum ether (PZPE), acetone (PZAC), and the hydroalcoholic (PZHY) extracts.

Materials and Methods:

The acute and sub-acute toxicities of extracts were evaluated according to OECD guidelines 425 and 407, respectively in female rats.

Results:

PZPE was more toxic than PZAC and PZHA, based on LD50 values of 93.45, 928.4, and 928.4 mg/kg, respectively. This potency difference directly correlates with the plumbagin content of extracts. With regard to sub-acute toxicity, a significant increase in organ weights (liver, adrenal glands, and/or heart) was observed in PZPE and PZAC treated groups. All extracts produced a significant increase in serum aspartate aminotransferase and urea, and PZAC produced a significant increase in serum creatinine as compared to control. A decrease in hematocrit was observed in the highest dose PZPE group, and a decrease in leukocytes was observed in all PZAC groups. Hepatic and renal changes were observed in all extract treated groups.

Conclusion:

The findings of our study, thus demonstrate that liver and kidney are the primary organs being adversely affected following sub-acute administration of P. zeylanica root extract in rats.

Experimental Studies on the Systemic Toxicity and Biodistribution of Synthesized Calcium Phosphate Nanoparticles After Oral Administration in Rats

BACKGROUND AND OBJECTIVE

Nanoparticles have special properties, such as higher surface-to-volume ratio and higher reactivity, which increases cell penetrability and enhance their applicability in the field of medicine, especially in the case where other drugs are ineffective. Calcium phosphate nanoparticles (CPNP) and their encapsulation with therapeutic and/or diagnostic agents is such an agent synthesized. However, there are concerns related to the colloidal stability of these nanoparticles, which are reflected in their tendency to form aggregates in the physiological milieu. Therefore, successful translation of these nanoparticles from laboratory to the clinic requires studies of biodistribution and biocompatibility of nanoparticles for in vivo biomedical applications.

METHOD

Calcium phosphate nanoparticles synthesized and were tagged with a fluorophore and surface stabilized with trisilanol for stable aqueous dispersion. The in vivo biodistribution and sub-acute toxicological studies were done for orally-administered calcium phosphate nanoparticles.

RESULTS

The biodistribution studies indicated that these nanoparticles were not prone to rapid degradation or excretion in the body, were long-circulating, and could appreciably permeate to the brain. Body/organ weight and biochemical analyses did not reveal much difference between nanoparticle-administered and saline-administered (control) groups. Finally, histopathological analyses of major organs such as liver, lungs, heart, stomach and kidney, did not reveal significant abnormalities in the treatment groups.

CONCLUSION

Thus, it is evident from these sub-acute toxicity studies that the nanoparticles appear to be non-toxic to rats following oral administration. These observations can have significant implications in calcium-phosphate nanoparticle-mediated non-toxic drug delivery to target organs, such as brain, via non-invasive, oral route.

Hematological Alterations on Sub-acute Exposure to Flubendiamide in Sprague Dawley Rats

Background:

Pesticide poisoning is a common occurrence around the world. Pesticides can act on various body systems resulting in toxicity. Flubendiamide is a new generation pesticide, reported to have better activity against Lepidopteran insects. The present study was carried out with an objective to analyze the effects of flubendiamide sub-acute exposure on hematology of rats.

Materials and Methods:

Male and female Sprague Dawley (SD) rats (9–11 weeks) were divided into five groups with six animals in each group. First group served as control, while the rest were exposed to ascending oral doses of flubendiamide (125, 250, 500 and 1000 mg/kg) for 28 days. After the trial period, blood was collected in heparinized vials and analyzed using Siemens ADVIA 2120^® autoanalyzer. Various erythrocytic, platelet and leukocyte parameters were measured and analyzed using statistical tests by one-way analysis of variance (ANOVA) and t-test using Statistical Package for Social Sciences (SPSS)^® 20 software.

Results:

After processing the data through statistical analysis, it was observed that the effect of flubendiamide exposure on female rats was negligible. The only significant change observed in the female rats was that in total erythrocytic count, while rest of the parameters showed non-significant bidirectional changes. In males, many parameters viz., total leukocyte count (TLC), total erythrocyte count (TEC), packed cell volume (PCV), mean corpuscular volume (MCV), platelet count (PC), mean platelet volume (MPV), platelet distribution width (PDW), hemoglobin distribution width (HDW), large platelets (LPT) and plateletcrit (PCT) expressed significant difference when compared to control.

Conclusion:

Many of the changes were dose independent, but sex specific. This lead to the hypothesis that saturation toxicokinetics might be one of the reasons for this varied response, which can only be evaluated after further testing.

Hepatoprotective activity of Tephrosia purpurea against arsenic induced toxicity in rats

AIM

The present study was conducted to evaluate the hepatoprotective activity of Tephrosia purpurea (TP) against sodium arsenite (NaAsO2) induced sub-acute toxicity in rats.

MATERIALS AND METHODS

Twenty four wistar albino rats of either sex were randomly divided into three groups. Group II and III were orally administered with sodium arsenite (10 mg/kg) daily in drinking water for 28 days. Additionally Group III was orally treated with hydro-alcoholic extract of Tephrosia purpurea (TP) @ 500 mg/kg daily for the same time period, whereas only deionized water was given to Group I (control). Serum biomarker levels, oxidative stress parameters and arsenic concentration were assessed in liver. Histopathology was also conducted.

RESULTS

It has been seen that TPE (500 mg/kg) significantly (P < 0.01) reduced serum ALT, AST, ALP activity and increased total protein and reduced necrosis and inflammation in liver of group III compared to group II. A significantly (P < 0.01) higher LPO and lower GSH levels without change in SOD activity in liver was also observed in group II compared to group III, though there was no significant difference in arsenic accumulation between them. The plant extract also protects the animals of group III from significant (P < 0.01) reduction in body weight.

CONCLUSION

Our study shows that supplementation of Tephrosia purpurea extract (500 mg/kg) could ameliorate the hepatotoxic action of arsenic.

Ameliorative Effect of Tephrosia Purpurea in Arsenic-induced Nephrotoxicity in Rats

Objectives:

The present investigation was conducted to evaluate the nephroprotective activity of Tephrosia purpurea (TPE) against arsenic-induced toxicity.

Materials and Methods:

Twenty four number of wistar rats were equally divided into three groups. Sodium arsenite (10 mg/kg) was orally given to group I for 28 days, additionally group II was orally treated with TPE (500 mg/kg), while the control group was kept untreated with neither arsenic nor TPE. Serum biomarker levels, oxidative stress indices and arsenic concentration in kidney were estimated. Histopathology of kidney was also conducted.

Results:

Group II animals show significantly reduced blood urea nitrogen and plasma creatinine, and increased serum albumin level compared to group I. The higher lipid peroxidation with exhausted superoxide dismutase activity and reduced glutathione level were noticed in group I compared to group II. There was no significant difference in arsenic accumulation in kidneys between the two arsenic treated groups, but the histopathology of kidney of group II rats revealed reduced necrosis and intact tubular architecture as compared to group I.

Conclusions:

Tephrosia Purpurea extract has a significant role in protecting the animals from arsenic-induced nephrotoxicity.

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.

Acute toxicity and the 28-day repeated dose study of a Siddha medicine Nuna Kadugu in rats

BACKGROUND

Nuna Kadugu (NK), a Siddha medicine prepared from leaves and fruits of Morinda Pubescens, used for the treatment of various skin diseases. Though NK has been widely used for several decades, no scientific report was available on its safety. Present study was undertaken to demonstrate the oral toxicity of NK in Sprague Dawley rats.

METHODS

Acute and 28-day repeated oral toxicity studies were performed following OECD test guidelines 423 and 407, respectively, with minor modifications. In acute oral toxicity study, NK was administered at 2000 mg/kg b.wt., p.o and animals were observed for toxic signs at 0, 0.5, 1, 4, 24 h and for next 14 days. Gross pathology was performed at the end of the study. In repeated dose, the 28- day oral toxicity study, NK was administered at 300, 600 and 900 mg/kg b.wt./p.o/day. Two satellite groups (control and high dose) were also maintained to determine the delayed onset toxicity of NK. Animals were observed for mortality, morbidity, body weight changes, feed and water intake. Haematology, clinical biochemistry, electrolytes, gross pathology, relative organ weight and histopathological examination were performed.

RESULTS

In acute toxicity study, no treatment related death or toxic signs were observed with NK administration. In the repeated dose study, no significant differences in body weight changes, food / water intake, haematology, clinical biochemistry and electrolytes content were observed between control and NK groups. No gross pathological findings and difference in relative organ weights were observed between control and NK treated rats. Histopathological examination revealed no abnormalities with NK treatment.

CONCLUSION

Acute study reveals that the LD50 of NK is greater than 2000 mg/kg, b.wt. in fasted female rats and can be classified as Category 5. 28-day repeated oral toxicity demonstrates that the No Observed Adverse Effect Level of NK is greater than 900 mg/kg b.wt./day, p.o in rats. There were no delayed effects in NK satellite group. In conclusion, NK was found to be non-toxic in the tested doses and experimental conditions.

Antidiabetic activity and phytochemical screening of crude extract of Stevia rebaudiana in alloxan-induced diabetic rats

BACKGROUND

Stevia rebaudiana regulates blood sugar, prevents hypertension and tooth decay. Other studies have shown that it has antibacterial as well as antiviral property.

METHODS

Preliminary phytochemical screening of aqueous, ether and methanolic extracts of S. rebaudiana was done. Acute and sub-acute toxicity were conducted on twenty four Albino rats, divided into one control (Group I) and three treatment groups viz. aqueous extract (Group II), ether extract (Group III) and methanolic extract (Group IV). For the study of antidiabetic effect of S. rebaudiana rats were divided into seven groups (n=6). Diabetes was induced by a single dose of 5% alloxan monohydrate (125 mg/kg, i.p.) after 24 hour fasting.Blood samples were analysed on day 0, 1, 5, 7, 14 and 28.

RESULTS

Phytochemical tests showed presence of different kinds of phyto-constituents in aqueous, ether and methanol extract of Stevia rebaudiana leaves. Daily single dose (2.0 g/kg) administration of aqueous extract (A.E.) , ether extract (E.E.) and methanol extract (M.E.) for 28 days of S. rebaudiana could not show any significant change in ALT and AST levels in rats. Blood sugar level was found to be decreased on day 28 in groups of rats treated with A.E., E.E. and M.E. of S. rebaudiana.

CONCLUSION

The extracts of Stevioside rebaudiana could decrease the blood glucose level in diabetic rats in time dependent manner.

Toxicity and immunomodulatory activity of fractions of Hibiscus sabdariffa Linn (family Malvaceae) in animal models

This study evaluated immunomodulatory properties and the sub-acute toxicity profile of two fractions of the aqueous alcoholic extract of the dried calyx of Hibiscus sabdariffa in experimental animals. Immunomodulatory activity was evaluated using red blood cell-induced immunostimulation. The fractions were not found to be toxic after 7-day administration, though there was severe weight loss with the residual water-soluble fraction (RWSF) and weight gain with the ethyl acetate soluble fraction (EAC). The EAC exhibited a significant dose-dependent immunostimulation (p<0.05) higher than that observed for levamisole (positive control). The residual water-soluble fraction exhibited immunostimulatory activity at 100 mg/kg body weight. The two fractions caused a significant reduction in production of tissue necrosis factor-alpha and an increase in interleukin 10 (IL-10).