Toxicological evaluation of the hydroethanolic extract of Dilodendron bipinnatum Radlk

Acute and subacute toxicological evaluation of the ethanol leaf extract of Morus mesozygia stapf. (Moraceae) in rodents

ETHNOPHARMACOLOGICAL RELEVANCE

Traditionally, the Morus mesozygia tree leaf has been used to manage maladies such as peptic ulcer, hyperglycemia, dermatitis, rheumatism, stomach-ache, arthritis, cough, malignancies, and malaria in parts of Africa.

AIM OF THE STUDY

The study aimed to evaluate the potential of ethanol leaf extract of Morus mesozygia (EEMm) to induce toxicity by employing both acute and sub-acute oral toxicity experimental models.

MATERIAL AND METHODS

The extract's cytotoxicity was studied using brine shrimps (Artemia salina) lethality assay (BSLA), while in the acute toxicity test, male and female mice were administered a single oral dose of EEMm (2000 mg/kg). Male and female Wistar rats received repeated doses of 100 or 500 mg/kg EEMm orally for 28 days in the sub-acute toxicity experiment. The phytochemical analysis of EEMm was done using the HPLC.

RESULTS

The BSLA revealed a moderate cytotoxic potential of the extract, with an LC50 of 567.13 ± 0.27 μg/mL. All the animals survived the acute toxicity test, with no significant changes in the relative organ weights, suggesting that LD50 is greater than 2000 mg/kg. The animal weights did not vary significantly in the sub-acute toxicity test neither were the alterations in biochemical and hematological tests pronounced, although the histoarchitectures of the kidney, liver and spleen indicated slight anomalies in the evaluated animals. The HPLC analysis revealed the presence of quercetin, ferulic acid, rutin, caffeic acid, morin and gallic acid.

CONCLUSIONS

Ethanol leaf extract of Morus mesozygia demonstrated a safe toxicity profile in rodents, supporting its broad folkloric use in African ethnomedicine.

In vitro and in vivo acute toxicity of an artificial butter flavoring

Flavorings used in cookies, electronic cigarettes, popcorn, and breads contain approximately 30 chemical compounds, which makes it difficult to determine and correlate signs and symptoms of acute, subacute or chronic toxicity. The aim of this study was to characterize a butter flavoring chemically and subsequently examine the in vitro and in vivo toxicological profile using cellular techniques, invertebrates, and lab mammals. For the first time, the ethyl butanoate was found as the main compound of a butter flavoring (97.75%) and 24 h-toxicity assay employing Artemia salina larvae revealed a linear effect and LC₅₀ value of 14.7 (13.7-15.7) mg/ml (R² = 0.9448). Previous reports about higher oral doses of ethyl butanoate were not found. Observational screening with doses between 150-1000 mg/kg by gavage displayed increased amount of defecation, palpebral ptosis, and grip strength reduction, predominantly at higher doses. The flavoring also produced clinical signs of toxicity and diazepam-like behavioral changes in mice, including loss of motor coordination, muscle relaxation, increase of locomotor activity and intestinal motility, and induction of diarrhea, with deaths occurring after 48 h exposure. This substance fits into category 3 of the Globally Harmonized System. Data demonstrated that butter flavoring altered the emotional state in Swiss mice and disrupted intestinal motility, which may be a result of neurochemical changes or direct lesions in the central/peripheral nervous systems.

Toxicological Safety Evaluation in Acute and 21-Day Studies of Ethanol Extract from Solanum lyratum Thunb

Solanum lyratum (Solanaceae) is a traditional Chinese medicine widely used to remedy cold fever, damp-heat jaundice, herpes, and nephritis dropsy. Despite its obvious therapeutic advantages, few toxicological studies have involved the efficacy and safety of its long-term treatment. To investigate the acute and subchronic toxicity of the extract of 75% ethanol extract of whole Solanum lyratum (ESL) after oral administration in mice. In acute toxicity experiment, mice were intragastric administration with ESL at doses of 1000, 2000, 3000, 4000, or 5000 mg/kg for 1 day. In a subchronic toxicity experiment, mice were intragastrically administration with ESL at doses of 180, 360, and 720 mg/kg and 0.9% saline for 21 days. Weight gain, hematological, biochemical, and histopathological analysis of vital organs were evaluated. The presence of aristolochic acid I in ESL was studied using UPLC-QTOF-MS. Phytochemical analysis indicated that the presence of aristolochic acid I in ESL was 0.0025 mg/g. This relatively low concentration is not enough to cause toxicity. In the acute toxicity experiment, neither mortality nor clinical alterations were shown, except for the mild transient diarrhea at 5000 mg/kg. So the LD₅₀ value of ESL was assessed to be more than 5000 mg/kg. In the subchronic toxicity experiment, neither mortality nor treatment-related clinical signs were observed. There was a significant increase in body weight, hemoglobin (HB), and urea nitrogen (BUN) after administration with ESL at 180 mg/kg. In addition, the weight of the stomach was increased and the hematocrit (HCT) was decreased after administration with ESL at 360 mg/kg. The changes were not considered treatment-related toxicological effects because the toxicity and histopathological analysis indicate that the extracts are safe for oral administration.

Dilodendron bipinnatum Radlk. extract alleviates ulcerative colitis induced by TNBS in rats by reducing inflammatory cell infiltration, TNF-α and IL-1β concentrations, IL-17 and COX-2 expressions, supporting mucus production and promotes an antioxidant effect

ETHNOPHARMACOLOGICAL RELEVANCE

Dilodendron bipinnatum (Sapindaceae) stem bark decoction and macerate were used to treat uterine inflammation, pain in general, dermatitis and bone fractures. These homemade preparations also have diuretic, stimulant, expectorants and sedative effects and are effective in treating worm infections in the Brazilian Pantanal population. Our previous research confirmed the anti-inflammatory activity of the hydroethanolic extract of inner stem bark of D. bipinnatum (HEDb).

AIM

This work aimed to investigate the efficacy of HEDb in ameliorating experimental colitis in rats and to elucidate the possible mechanisms involved in the anti-ulcerative colitis properties of HEDb in rats and Caco-2 cell line.

MATERIALS AND METHODS

The effects on cell viability, IL-8 and TNF-α in human colon adenocarcinoma (Caco-2) were determined by flow cytometer and ELISA. Wistar rats (n = 6-7) were orally gavaged with, vehicle (0.9% saline), HEDb at doses of 20, 100 or 500 mg/kg, or mesalazine at a dose of 500 mg/kg, at 48, 24 and 1 h prior to the administration of trinitrobenzene sulfonic acid via rectal administration to induce colitis. The anti-inflammatory effects of HEDb were assessed macroscopically, by myeloperoxidase (MPO) activity and for glutathione (GSH) concentration in the colon. Additionally, colonic histopathological analyses of UC severity were conducted by different staining methods (H&E, PAS and toluidine blue). Pro-inflammatory cytokines TNF-α and IL-1β were quantified in colonic tissue by ELISA and colonic expressions of COX-2 and IL-17 were analyzed by western blotting.

RESULTS

HEDb was shown to be non-cytotoxic with mean viability of 80% in Caco-2 cells. HEDb pre-treatments of 1, 5 or 20 μg/mL significantly reduced TNF-α production in Caco-2 cells by 21.8% (p < 0.05), 60.5 and 82.1% (p < 0.001) respectively following LPS treatment compared to LPS alone. However, no change in IL-8 production was observed. HEDb pre-treatment of rats subjected to TNBS significantly (p < 0.001) reduced colonic lesion score. Higher doses (100 and 500 mg/kg) caused a sharp downregulation of haemorrhagic damage, leukocyte infiltration, edema and restoration of mucus production. Moreover, mast cell degranulation was inhibited. Colonic MPO activity was reduced following all doses of HEDb, reaching 51.1% ± 1.51 (p < 0.05) with the highest dose. GSH concentration was restored by 58% and 70% following 100 and 500 mg/kg of HEDb, respectively. The oral treatment of HEDb at doses 20, 100 and 500 mg/kg decreased the concentrations of TNF-α and IL-1β at all doses in comparison to vehicle treated control. In addition, HEDb inhibited the COX-2 and IL-17 expressions with maximal effect at 500 mg/kg (60.3% and 65% respectively; p < 0.001). In all trials, the effect of HEDb at all doses being 20, 100 and 500 mg/kg was statistically comparable to mesalazine (500 mg/kg).

CONCLUSIONS

HEDb reduces colonic damage in the TNBS colitis model and relieves oxidative and inflammatory events, at least in part, by increasing mucus production, reducing leukocyte migration and reducing TNF-α (in vivo and in vitro), IL-1β, IL-17 and COX-2 expression. Therefore, HEDb requires further investigation as a candidate for treating IBD.

Assessment of 28-day oral toxicity and antipyretic activity of the saline extract from Pilosocereus gounellei (Cactaceae) stem in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Pilosocereus gounellei is a plant found in the Brazilian Caatinga and is popular due to its traditional uses in the treatment of inflammation. The present study was conducted to investigate the sub-acute toxicity of the saline extract from the stem of P. gounellei.

AIM OF THE STUDY

To evaluate the 28-day oral toxicity (through behavioral, biochemical, hematological, and morphological analysis) and the antipyretic activity of the extract in mice.

MATERIALS AND METHODS

A single oral dose (250, 500, and 1000 mg/kg) was administered daily over 28 consecutive days to male and female mice. Body weight, food and water intake, blood biochemical and hematological parameters, and urine composition were recorded. Histopathological examinations of the liver, kidney, spleen, lungs, and heart were performed and oxidative stress in the organs was evaluated by lipid peroxidation, superoxide dismutase (SOD), catalase (CAT), and nitrite analysis. The antipyretic effect of the 500 mg/kg dose was assessed using a yeast-induced pyrexia model.

RESULTS

Oral administration of the extract over 28 days did not affect body weight gain, food and water consumption, body temperature, and hematological parameters in male and female mice. Blood glucose, total cholesterol, and triglyceride levels in male and female mice were reduced. Protein in the urine and histological alterations in both the liver and lungs were detected in male and female mice treated with the highest dose of the extract. SOD levels in the liver and the spleen increased significantly in both sexes, whereas lipid peroxidation decreased in the spleen of male mice. The extract also exerted an antipyretic effect after the first 60 min of the evaluation until the end of the observation duration (180 min).

CONCLUSION

The saline extract from the stem of P. gounellei did not present significant toxic effects over 28 consecutive days and demonstrated antipyretic activity when administered orally. Moreover, the results suggest that the extract has potential hypoglycemic and hypolipidemic effects. Future studies are needed to investigate its pharmacological potential.

Dilodendron bipinnatum Radlk. ameliorates airway inflammation through multiple targets in a murine model of ovalbumin-induced allergic airway disease

ETHNOPHARMACOLOGICAL RELEVANCE

Dilodendron bipinnatum Radlk., Sapindaceae, a tree of the Mato Grosso Pantanal, is popularly known as "mulher-pobre". The decoction or infusion of its inner stem bark is used for treating inflammatory conditions.

AIM OF THE STUDY

To determine if a 70% hydroethanolic extract of Dilodendron bipinnatum stem bark (HEDb) is able to reduce allergic airway inflammation in a murine model of ovalbumin (OVA)-induced allergic asthma.

MATERIAL AND METHODS

The inner stem bark powder was macerated in a 70% hydroethanolic solution (1:3 w/v) to obtain HEDb. The induction of experimental asthma was accomplished as follows: on days 1 and 10, Swiss mice were sensitized by an intraperitoneal injection of OVA (100 µg/mL) and aluminum hydroxide (10 µg/mL). From day 19 to 24, animals (n = 6/per group) were treated (p.o.) twice a day with either vehicle (distilled water), HEDb (20, 100 and 500 mg/kg) or dexamethasone (0.5 mg/kg). Sham group animals were intraperitoneally injected and challenged with saline solution (0.9%) instead of OVA and received distilled water orally instead of HEDb, whereas the other groups were challenged with OVA (3% in saline) by aerosolization. On day 25, bronchoalveolar lavage fluid (BALF) was collected for the quantification of total leukocytes, neutrophils, eosinophils, mononuclear cells and Th2 cytokines (IL-4, IL-5, and IL-13). The lungs were collected for histopathological analysis and blood was assayed to determine serum IgE levels. The anti-inflammatory activity of HEDb was additionally confirmed by a lipoxygenase (LO) inhibitory assay in vitro.

RESULTS

Compared to the sham group, the OVA group showed significantly greater numbers of total leukocytes, neutrophils, eosinophils, and mononuclear cells, as well as inflammatory cytokines in BALF, and also IgE in the serum. HEDb treated mice showed a significant decrease in inflammatory cell accumulation in BALF, with the maximum response observed at 500 mg/kg. Furthermore, the levels of IL-4, IL-5 and IL-13 in BALF, and of IgE in serum, were also considerably reduced as compared to the OVA group. The histopathological examination of the lungs of mice in the vehicle group showed a significant increase in hemorrhagic damage, mucus, perivascular and peribronchial inflammatory cell infiltrates, as well as mast cell degranulation compared to sham. HEDb (100 and 500 mg/kg) remarkably decreased all these parameters, presenting at the highest dose an anti-inflammatory effect comparable to that of dexamethasone (0.5 mg/kg). HEDb also had notable direct anti-inflammatory properties demonstrated by the inhibition of 15-LO activity in vitro (IC₅₀ = 1.0-5.0 µg/mL).

CONCLUSIONS

These results somewhat agree on the popular use of the inner stem bark of D. bipinnatum as a treatment for allergic asthma. The HEDb exhibits significant anti-inflammatory activity in the OVA-induced mouse model of allergic asthma, possibly due to the down-regulation of the Th2 responses and LO inhibition, resulting in improvements in all analyzed inflammatory parameters.

The hydroethanolic Litchi chinensis leaf extract alleviate hepatic injury induced by carbon tetrachloride (CCl4) through inhibition of hepatic inflammation

Various medicinal plants are traditionally used in a hepatoprotective manner, like, for example, the Litchi chinensis leaf infusion that is employed in Chinese medicine as liver tonics to strengthen hepatic functioning. In this context, the present study was designed to evaluate the hepatoprotective and acute toxicological effects of hydroethanolic L. chinensis leaf extract in HepG2 cells and mice. Specifically, the cytotoxicity and hepatoprotective activities of L. chinensis leaf extract were evaluated in HepG2 cells and in vivo against carbon tetrachloride (CCl₄)-induced acute liver injury. The administration of CCl₄ in mice provokes cell swelling, loss of sinusoid capillary spaces and structural disarrangement of the hepatic lobe, apoptosis and leukocyte infiltration. Further, CCl₄ evokes an increase in serum alanine aminotransferase (ALT), tumor necrosis factor (TNF) and interleukin-6 (IL-6) levels in hepatic tissue. However, Silymarin, the positive control, and the L. chinensis extract were able to restore the viability of cells treated with CCl₄ at all concentrations evaluated, reduced the inflammatory parameters, TNF and IL-6, reestablished hepatic tissue morphology and did not induce acute toxicological alterations. The data obtained underscore that the extract from L. chinensis leaves features hepatoprotective activity, corroborating with ethnopharmacological use, and does not lead to acute toxicological effects.

Chemical characterization, toxicology and mechanism of gastric antiulcer action of essential oil from Gallesia integrifolia (Spreng.) Harms in the in vitro and in vivo experimental models

Gallesia integrifolia is a Brazilian Amazon tree whose bark decoction is popularly used to treat peptic ulcer. The essential oil from the inner stem bark of G. integrifolia (EOGi) was chemically characterized by GC/MS. The in vitro cytotoxicity and genotoxicity were evaluated in CHO-K1 cells, while the in vivo oral acute toxicity was performed in mice. The gastroprotective effect of EOGi was assessed in acidified ethanol and piroxicam and ulcer healing on acetic acid -induced ulcer models in rodents. Anti-secretory, mucus, K⁺-ATP channels, prostaglandins (PGs), nitric oxide (NO), TNF-α, IL-1β, IL-10, catalase (CAT) and myeloperoxidase (MPO) activities and in vitro Helicobacter pylori action by EOGi were evaluated. EOGi exhibited cytotoxic effects only at 72h and no acute toxicity. EOGi showed gastroprotective and ulcer healing effects. EOGi gastroprotection was attenuated by indomethacin pre-treatment. Gastric volume and total acidity were reduced, while gastric pH was elevated. EOGi increased mucus and NO productions and CAT activity, and inhibited MPO activity, TNF-α and IL-1β concentrations and augmented IL-10. EOGi was not active against H. pylori. These results indicated that EOGi is safe and exerts preventive and curative gastric ulcer effects by multitarget actions. Twenty compounds were identified and (-)-alpha-santalene was the main compound.

Dilodendron bipinnatum Radlk. inhibits pro-inflammatory mediators through the induction of MKP-1 and the down-regulation of MAPKp38/JNK/NF-κB pathways and COX-2 in LPS-activated RAW 264.7 cells

ETHNOPHARMACOLOGICAL RELEVANCE

The stem bark of Dilodendron bipinnatum Radlk. (Sapindaceae), a tree native to Pantanal of Mato Grosso, Brazil, popularly known as "mulher-pobre" (poor woman), has been historically used by the locals, after decoction and maceration, for the treatment of inflammatory conditions. We have recently shown that these preparations indeed possess anti-inflammatory properties, which are mediated by the inhibition of cell migration and the modulation of Th1 and Th2 cytokines. The NO pathway was not affected.

AIM OF THE PRESENT STUDY

The aim of the present study was to further investigate the mechanisms responsible for the anti-inflammatory properties of the hydroethanolic extract of the stem bark of Dilodendron bipinnatum (HEDb).

MATERIALS AND METHODS

HEDb was obtained by maceration of the stem bark of D. bipinnatum as previously described. The corresponding effects on a macrophage-like cell line, RAW 264.7, were investigated. The apoptosis of RAW 264.7 upon treatment with LPS, HEDb and N-acetyl-L-cysteine (NAC) was assessed by flow cytometry, using an Annexin V-PE kit. The production of inflammatory cytokines (TNF-α, IL-1β and IL-10) and PGE₂ were evaluated by ELISA, after cell challenge with LPS. The intracellular redox state and changes in mitochondrial membrane potential were also assessed by flow cytometry, using DCFH-DA and JC-1 as probes. The protein expression levels of MAPK p-p38, p-ERK, p-JNK, MKP-1 and COX-2 were analysed by western blotting. Nuclear translocation of NF-қB was assessed by immunofluorescence microscopy. The quantified results are presented as a nuclear:cytoplasmic ratio.

RESULTS

LPS, HEDb and NAC did not appear to decrease the number of viable cells in comparison to control treatment. HEDb attenuated the production of pro-inflammatory cytokines (IL-1β and TNF-α) and PGE₂ induced by LPS but did not affect IL-10. The production of ROS was also inhibited by HEDb (1, 5 or 20µg/mL), even at the lowest concentration; at 20µg/mL, HEDb was more effective than NAC, which was used as a positive control (74.1% and 66.2% inhibition of LPS's effect, respectively). LPS induced an increase in ΔΨm (19.2%, p<0.001), while HEDb inhibited the change in ΔΨm (7.7% at 20µg/mL, p<0.001). The results of western blotting showed that HEDb inhibited the expression of MAPK p-p38, p-JNK and COX-2, while the expression of MKP-1 was increased. p-ERK was not affected. LPS promoted the nuclear translocation of NF-қB p65 (67%, p<0.01) in RAW 264.7 cells, in comparison to baseline (33%). Pre-treatment with HEDb inhibited this translocation of NF-κB p65 (58% at 20µg/mL, p<0.001).

CONCLUSION

HEDb has a potent anti-inflammatory activity and acts on multiple targets and biological pathways of potential therapeutic relevance.

Acute and sub-acute toxicological evaluation of lyophilized Nymphaea x rubra Roxb. ex Andrews rhizome extract

Nymphaea x rubra Roxb. ex Andrews (N. rubra) has been widely reported for immunomodulatory properties and treatment of piles, bleeding nose and dysentery in traditional medicinal systems. However, its in-vitro and in-vivo toxicity studies have never been investigated. So, the present study was designed to investigate in-vitro and in-vivo toxicity of methanolic extract of N. rubra rhizome in rats. In-vitro cytotoxicity studies were conducted for different doses of extract in N2a cell lines. For in-vivo toxicity studies, SD rats were divided into three groups and administered with 0, 300 and 2000 mg/kg b. w., p. o., of N. rubra extract respectively. In acute toxicity studies, female animals after extract administration animals were sacrificed for hematological profiling and gross necropsy. In sub-acute toxicity studies, both male and female animals were administered with extract daily for 14 days and were sacrificed for hematological, biochemical and histological examination. Body weight and food water intake was measured daily and animals were observed for visual toxic effects, behavioral changes and mortality. During in-vivo toxicity studies, none of the animals showed signs of toxicity and mortality during toxicity studies. The present findings suggest its safety and NOAEL of N. rubra rhizome extract to be > 2000 mg/kg b. w.

Antiproliferative and toxicological properties of methanolic extract obtained from Solanum capsicoides All. seeds and carpesterol

Natural products are considered important sources of potential chemotherapeutic agents. Here, we evaluated the antiproliferative activity and the toxicological effects of the methanolic extract and a pure compound obtained from Solanum capsicoides seeds. The phytochemical profile was analyzed by chromatographic and spectroscopy methods. The acute toxicity was assessed in mice orally treated with the extract (2000 mg/kg), in vitro hemolytic activity and micronucleus test. The mutagenicity, developmental toxicity, and lethal dose (LD50) of carpesterol were estimated by the Toxicity Estimation Software Tool (TEST) software. A sulforhodamine B assay was employed to evaluate the antiproliferative activity. The toxicological assays did not observe signs of toxicity, either during the behavioral observations or in the autopsies, as well as no mutagenicity and hemolytic activity. The carpesterol did not present mutagenic effect and hemolytic activity but presents developmental toxicology and LD50 of 410 mg/kg in toxicity estimations by the TEST software. The S. capsicoides extract exhibited antiproliferative activity mainly in leukemia (K562) cell lineage. However, carpesterol presented antiproliferative activity in glioma (U251), breast (MCF-7), kidney (786-0), ovary (OVCAR-03), and K562 cell lineages. The data obtained show that S. capsicoides extract presents antiproliferative and does not present toxicological effects. In addition, it was shown for the first time the antiproliferative and toxicological parameters of carpesterol.