Hippocratic screening and subchronic oral toxicity assessments of the methanol extract of Vatairea macrocarpa heartwood in rodents

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.

Sphaeranthus senegalensis DC: Evaluation of chemical constituents, oral safety, gastroprotective activity, and mechanism of action of its hydroethanolic extract

ETHNOPHARMACOLOGICAL RELEVANCE

Sphaeranthus senegalensis DC is a seasonal herb with a spicy smell that grows wild in wet grounds of tropical Africa and Asia. The plant is used in folk medicine for the treatment of various diseases; that includes its use to treat gastric ulcers.

AIM OF THE STUDY

This study aimed to investigate the chemical constituents of the hydroethanolic extract of Sphaeranthus senegalensis DC and evaluate its oral safety, gastroprotective activity, and mechanisms of action using laboratory models in rats and mice.

MATERIALS AND METHODS

Hydroethanolic extract (70%) of the powdered whole dried material was prepared, and chemical constituents of the resultant extract (denoted HESs) standardized using the high-performance liquid chromatography (HPLC) method. The safety profile of HESs was assessed using 2000 mg/kg, oral (p.o.) for Hippocratic screening in mice, and 800 mg/kg, p.o. for 28 days subchronic toxicity assay in rats. The gastroprotective effect of HESs (25, 100, and 400 mg/kg, p.o.) was investigated using acidified ethanol, piroxicam, water immobilization stress, and acetic acid-induced ulcer models. The gastroprotective mechanisms of HESs were evaluated using its effect on gastric mucus protection, nitric oxide modulation, gastric juice secretory parameters, catalase and myeloperoxidase activities. Histological analysis of the stomach tissues was also carried out.

RESULTS

The HPLC analysis indicated the presence of 25.94% phenolics (gallic acid, caffeic acid, and ferulic acid) and 14.53% flavonoids (rutin, morin, luteolin, quercetin, and apigenin). Hippocratic screening and the 28 days subchronic study indicated that HESs is generally safe. Result shows that oral administration of HESs (25, 100 and 400 mg/kg) alleviated the severity of the gastric ulcers induced by acidified ethanol by 35.65% (p < 0.05), 48.70% (p < 0.05) and 78.02% (p < 0.001) respectively; exhibited gastroprotective effect against the gastric lesions induced by piroxicam by 37.97% (p < 0.05), 53.27% (p < 0.05) and 76.23% (p < 0.001) respectively; and decreased the severity of the water immobilization stress-induced gastric ulcers by 32.43% (p < 0.05), 55.26% (p < 0.01) and 74.05% (p < 0.001) respectively, when compared to the vehicle control group. The mechanisms of action assays indicated that the gastroprotective activity was mediated mainly through gastroprotection, antisecretory, and antioxidant activities. Histological analysis showed it inhibited epithelial cell loss, vascular damage, and leucocyte infiltration.

CONCLUSION

HESs contains useful phytochemicals, is safe, and exhibited significant gastroprotective action. The results provided justification for its claim in the treatment of gastric ulcers and its evaluation for potential application as a gastroprotective agent.

Evaluation of cytotoxic potential, oral toxicity, genotoxicity, and mutagenicity of organic extracts of Pityrocarpa moniliformis

The objective of this study was to determine the cytotoxicity of organic extracts of P. moniliformis in vitro and identify the acute toxicity and genotoxicity in vivo. The leaves were extracted using three organic solvents (cyclohexane [EP1], ethyl acetate [EP2], and methanol [EP3]). Phytochemical qualitative analysis was performed by thin layer chromatography (TLC). Cytotoxicity tests were performed on human embryonic kidney (HEK) cells and J774 murine macrophages. Acute toxicity in mice was measured after intraperitoneal (ip) administration of 2000 mg/kg, while evaluation of genotoxicity and mutagenicity were assessed using the comet assay and the micronucleus (MN) test, respectively. The TLC analysis of the extracts revealed the presence of flavonoids, triterpenes, steroids, and saponins. In the cytotoxicity assay, extracts EP1 and EP3 altered proliferation of HEK cells, and all organic extracts increased the viability of J774 cells. In the toxicity tests, no deaths or behavioral alterations were observed in mice exposed to the acute dose of the extracts. Although some extracts led to changes in hematological and histological parameters, these results did not indicate physiological changes. In relation to the MN test and comet assay, no significant changes were detected in the DNA of the animals tested with the extracts EP1, EP2, and EP3. Thus, extracts of P. moniliformis were not considered to be toxic and did not induce formation of MN or damage to cellular DNA in the genotoxicity tests.

Toxicological evaluation of the hydroethanolic extract of Dilodendron bipinnatum Radlk

ETHNOPHARMACOLOGICAL RELEVANCE

Dilodendron bipinnatum Radlk., Sapindaceae, is popularly known as 'mulher-pobre'. Its stem bark macerate or decoction is popularly used mainly to treat uterine inflammation and bone fractures. Acute oral and subchronic toxicities of the hydroethanolic extract of Dilodendron bipinnatum (HEDb) were investigated as well as the classes of phytochemical present in the extract.

MATERIALS AND METHODS

Acute toxicity of HEDb was investigated by hippocratic screening in Swiss mice, cytotoxicity and potential genotoxic effect were evaluated with micronucleus test in the CHO-k1cells. Subchronic oral toxicity of HEDb was assessed in Wistar rats with graded doses of HEDb repeatedly administered for 30 days, in order to evaluate the behavioral changes, weight gain, water and feed consumption, urine and feces excretion, hematological and biochemical parameters and histopathological examinations of vital organs.

RESULTS

In hippocratic screening doses up to 5000 mg/kg p.o. did not cause any changes in female mice, while signs of reduction in motility, increased respiratory rate and tail erection were observed in male mice but were all reversed within an hour. In cytotoxicity assay, IC50 was 118±1.55 µg/mL in CHO-k1 cells. Micronucleus test demonstrated that the plant extract is non-genotoxic. In subchronic toxicity studies, minor change was observed as an increase in the urine output in the last 18 days of treatment with 500 mg/kg of HEDb, while other parameters remained unchanged. All alterations observed were discrete and minor in nature and were not accompanied by any relevant clinical signs or any toxicologically significant biochemical, hematological and histopathological changes. Preliminary phytochemical analysis revealed the presence of aurones, chalcones, coumarins, flavonones, flavononoids, phenols, and saponins.

CONCLUSION

The results demonstrate high safety profile of HEDb in both experimental animals and cell models assays. However, there may be risk of hepatotoxicity in the use of the extract at high doses for a prolonged period.