Evaluation of genotoxicity and subchronic toxicity of the standardized leaves infusion extract of Copaifera malmei Harms in experimental models

Discovery of (E)-3-(4-chlorophenyl)-N-(5-hydroxypentyl)acrylamide among N-substituted cinnamamide derivatives as a novel cosmetic ingredient for hyperpigmentation

Hyperpigmentation disorders may result from inappropriate melanin deposition and/or excessive melanin synthesis. They are classified mainly as aesthetic problems, but they can significantly affect human health by decreasing self-esteem. There are available only limited treatment options for hyperpigmentation disorder, among others, cosmetic products applied topically. Depigmenting ingredients were found to be ineffective and characterized by various side effects. As a result, many efforts are made to discover novel, potent, and safe melanogenesis inhibitors for possible use in topical cosmetic depigmenting formulations. Cinnamic acid derivatives constitute a widely tested group for that purpose. This article reports research in the group of N-alkyl cinnamamide derivatives (un)substituted in phenyl ring. Among tested series, (E)-3-(4-chlorophenyl)-N-(5-hydroxypentyl)acrylamide (compound 21) showed the most promising inhibitory properties in mushroom tyrosinase assay (IC50 = 36.98 ± 1.07 µM for monophenolase activity, IC50 = 146.71 ± 16.82 µM for diphenolase activity) and melanin production inhibition in B16F10 mouse melanoma cell line at concentration 6.25 µM resulting probably from decreasing of Tyr, Mitf, Tyrp-1, and Tyrp-2 genes expression. This compound also showed melanin production inhibitory properties in pigmented reconstructed human epidermis when used in 1 % and 2 % solutions in 50 % PEG400. In vitro evaluation of its safety profile showed no cytotoxicity to human keratinocytes HaCaT, human skin fibroblasts BJ, and human primary epidermal melanocytes HEMa, no mutagenicity in the Ames test, no genotoxicity in micronucleus test, no phototoxicity, as well as no skin irritation potential tested in PEG400 solution. This compound was also shown to penetrate across the epidermis to reach the possible site of action. The performed research led to classify (E)-3-(4-chlorophenyl)-N-(5-hydroxypentyl)acrylamide as a novel potential depigmenting cosmetic ingredient.

Evaluation of the toxicity of the hydroethanolic extract of the stem bark of Virola elongata (Benth.) Warb. in in vitro and in vivo models

ETHNOPHARMACOLOGICAL RELEVANCE

Virola elongata (Benth.) Warb. (Myrsticaceae), referred to as "mucuíba" in Mato Grosso, is a native tree species that can be found in the Amazon Rainforest regions of South America and the Tropical Forests of Central America. The macerated extracts from the stem bark of this tree have been traditionally used to address various health issues, including gastric ulcers, infections, inflammations, and other ailments. In scientific literature, V. elongata has demonstrated pharmacological properties such as antiulcer, gastroprotective, antiproliferative, antimitotic, and psychoactive effects. Nevertheless, it is important to note that the safety profile of V. elongata has not been thoroughly established.

AIM OF THE STUDY

To evaluate the toxicity of the hydroethanolic extract of the stem bark of Virola elongata (HEVe) in experimental models in vivo and in vitro.

MATERIALS AND METHODS

HEVe was obtained by macerating the stem bark powder in 70% hydroethanolic solution (1:10 w/v). The cytotoxicity of HEVe (3.125-200 μg/mL) was evaluated by Alamar blue assay in Chinese hamster ovary epithelial cells (CHO-k1) and human gastric adenocarcinoma (AGS). Genotoxicity assessment of HEVe (10, 30, or 100 μg/mL) was performed in CHO-k1 cells by the micronucleus test. The acute toxicity of HEVe was assessed by single-dose oral administration (2000 mg/kg) in mice of both sexes. The subacute toxicity of HEVe was assessed by oral administration of 300, 600, and 1200 mg/kg of the extract over 30 days in rats. Clinical observations of toxicological parameters were noted and pooled every 6 days. After the treatment period, blood was collected for hematological and biochemical analyses, and some organs were removed for macroscopic and histopathological analyses.

RESULTS

HEVe did not show cytotoxicity in CHO-K1 and AGS cells (IC50 > 200 μg/mL) and did not cause DNA damage in CHO-k1 cells. Oral administration of HEVe in a single dose of 2000 mg/kg did not result in the death of the mice, with a reduction in body weight variation (33.03%, p < 0.05) and an increase in the relative weight of the stomach (12 0.82%, p < 0.05) in male mice, and increased relative weight of the spleen (25.00%, p < 0.01) in female mice. In the assessment of subacute toxicity, HEVe did not result in the death of the animals over the 30 days. A reduction (p < 0.05) in water consumption of 36.65% and 34.12% was observed in the groups treated with 300 and 600 mg/kg, respectively, of HEVe on D6., and the urine excretion of animals treated with 600 mg/kg of HEVe showed an increase (p < 0.05) throughout the experiment, with a maximum value of 46.72% on D12. The blood counts showed that the dose of 300 mg/kg reduced (p < 0.05) the absolute number of lymphocytes, while the doses of 300, 600, or 1200 mg/kg of HEVe reduced the red blood cell count in whole blood by 24.84% (p < 0.01), 16.72% (p < 0.05), and 22.14% (p < 0.01), and the absolute number of monocytes (p < 0.05) in 59.77%, 65.51%, and 79.81%, respectively. As for the biochemical parameters, the glucose level found increased by 22.41% (p < 0.05) only at the highest dose, while creatinine was reduced by 44.71% (p < 0.05) at the dose of 300 mg/kg of HEVe. In animals treated with the three doses tested, plasma levels of AST and alkaline phosphatase showed a reduction (p < 0.05) with the vehicle group. However, the hematological and biochemical changes observed are within the physiological limits for this animal species. No macroscopic and histopathological changes were observed in the organs of the animals treated with the three doses of HEVe within 30 days.

CONCLUSION

The results showed that HEVe did not show cytotoxicity or genotoxicity in vitro. HEVe proved to be safe in rodents in both acute and subacute toxicity tests. In rats, the no-observed-adverse-effect level (NOAEL) dose was greater than 1200 mg/kg p. o. in rats.

Brasiliensic acid: in vitro cytotoxic and genotoxic, in vivo acute toxicity and in silico pharmacological prediction of a new promising molecule

Brasiliensic acid (Bras) is a chromanone isolated from Calophyllum brasiliense Cambèss. bark extracts with confirmed potential activity on gastric ulcer and Helicobacter pylori infection. This study aimed to investigate the in vitro and in vivo toxicity of Bras and molecular docking studies on its interactions with the H. pylori virulence factors and selected gastric cancer-related proteins. Cytotoxicity was evaluated by alamarBlue© assay, genotoxicity by micronucleus and comet assays, and on cell cycle by flow cytometry, using Chinese hamster epithelial ovary cells. Bras was not cytotoxic to CHO-K1 cells, and caused no chromosomal aberrations, nor altered DNA integrity. Furthermore, Bras inhibited damages to DNA by H2O2 at 1.16 µM. No cell cycle arrest was observed, but apoptosis accounted for 31.2% of the cell death observed in the CHO-K1 at 24 h incubation of the IC50. Oral acute toxicity by Hippocratic screening test in mice showed no relevant behavioral change/mortality seen up to 1,000 mg/kg. The molecular docking approach indicated potential interactions between Bras and the various targets for peptic ulcer and gastric cancer, notably CagA virulence factor of H. pylori and VEGFR-2. In conclusion, Bras is apparently safe and an optimization for Bras can be considered for gastric ulcer and cancer.Communicated by Ramaswamy H. Sarma.

Evaluation of Two Novel Hydantoin Derivatives Using Reconstructed Human Skin Model EpiskinTM: Perspectives for Application as Potential Sunscreen Agents

This study aimed to assess two novel 5-arylideneimidazolidine-2,4-dione (hydantoin) derivatives (JH3 and JH10) demonstrating photoprotective activity using the reconstructed human skin model Episkin^TM. The skin permeability, irritation, and phototoxicity of the compounds was evaluated in vitro. Moreover, the in vitro genotoxicity and human metabolism of both compounds was studied. For skin permeation and irritation experiments, the test compounds were incorporated into a formulation. It was shown that JH3 and JH10 display no skin irritation and no phototoxicity. Both compounds did not markedly enhance the frequency of micronuclei in CHO-K1 cells in the micronucleus assay. Preliminary in vitro studies with liver microsomes demonstrated that hydrolysis appears to constitute their important metabolic pathway. Episkin^TM permeability experiments showed that JH3 permeability was lower than or close to currently used UV filters, whereas JH10 had the potential to permeate the skin. Therefore, a restriction of this compound permeability should be obtained by choosing the right vehicle or by optimizing it, which should be addressed in future studies.

Neuropathic pain-alleviating activity of novel 5-HT6 receptor inverse agonists derived from 2-aryl-1H-pyrrole-3-carboxamide

The diverse signaling pathways engaged by serotonin type 6 receptor (5-HT₆R) together with its high constitutive activity suggests different types of pharmacological interventions for the treatment of CNS disorders. Non-physiological activation of mTOR kinase by constitutively active 5-HT₆R under neuropathic pain conditions focused our attention on the possible repurposing of 5-HT₆R inverse agonists as a strategy to treat painful symptoms associated with neuropathies of different etiologies. Herein, we report the identification of compound 33 derived from the library of 2-aryl-1H-pyrrole-3-carboxamides as a potential analgesic agent. Compound 33 behaves as a potent 5-HT₆R inverse agonist at Gs, Cdk5, and mTOR signaling. Preliminary ADME/Tox studies revealed preferential distribution of 33 to the CNS and placed it in the low-risk safety space. Finally, compound 33 dose-dependently reduced tactile allodynia in spinal nerve ligation (SNL)-induced neuropathic rats.

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.

Copaifera malmei Harms leaves infusion attenuates TNBS-ulcerative colitis through modulation of cytokines, oxidative stress and mucus in experimental rats

ETHNOPHARMACOLOGICAL RELEVANCE

Ethnobotanical studies show that the infusion of the leaves from Copaifera malmei Harms (Fabaceae) has been utilized in the Brazilian traditional medicine to treat provocative and gastrointestinal diseases, among others. Recently, our research team has shown that an infusion extract of the leaves of C. malmei has a strong antiulcer activity and its oral use gives no indications of toxicity.

AIM OF THE STUDY

The aim of the study is to evaluate the anti-inflammatory intestinal effect of an infusion extract from the leaves of Copaifera malmei (IECm) in an animal model of ulcerative colitis induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS).

MATERIALS AND METHODS

Acute intestinal inflammation was induced in male Wistar rats by TNBS in 20% EtOH (0.25 mL). IECm was administered by oral gavage (for 72, 48, 24 and 2 h) preceding the induction of ulcerative colitis. The colon damage and degree of inflammation were evaluated by morphological observation scores and colon weight. The improved colonic mucosal injury, oxidative stress and inflammatory response were assessed by histopathological investigation and by estimating myeloperoxidase (MPO) activity, malondialdehyde (MDA) and glutathione (GSH) levels and tumor necrosis factor (TNF), interleukin 1β (IL1-β), IL-17 and IL-10 colon tissue concentrations. The histopathological changes were done on the colon tissues by hematoxylin and eosin and Periodic Acid-Schiff staining were utilized to measure the mucus.

RESULTS

Pre-treatment (25, 100 and 400 mg/kg) with IECm altogether diminished the intestinal inflammation prompted by TNBS in rats by diminishing colonic score by 69.12% (p < 0.01), 19.87% (p < 0.05) and 67.60% (p < 0.01), individually. Improvement of colonic mucosal injury by treatment with IECm was shown by a decline in MPO activity at dosages 25 and 400 mg/kg by 67.98% and 59.68% (p < 0.001), MDA levels 64.80% and 80.00% (p < 0.01) and an expansion in GSH content at all portions (62.53%, 53.38% and 81.20% p < 0.05) compared with vehicle control group. IECm additionally prevention of intestinal inflammation as confirm by decreased cytokine levels, for example, TNF (31.26%, p < 0.05, 50.68% and 45.95%, p < 0.01), IL1-β (56.41%, 58.83% and 56.65%, p < 0.001), IL-17 (51.66%, p < 0.001, 22.23%, p < 0.05 and 49.67%, p < 0.001) and increased the IL-10 levels at 25 and 400 mg/kg (57.13%, p < 0.01 and 35.83%, p < 0.05) respectively. Histopathological examination of the colon tissue displayed recovery of ulcerative colitis of IECm treated animals by reducing leukocyte infiltrate, epithelial, submucosal and muscular layer damages and maintaining mucus production.

CONCLUSION

These findings revealed that IECm was effective and possess anti-colitic activities in a rodent model of UC and can be useful in inflammatory bowel diseases (IBD). The pre-treatment with IECm decreased intestinal inflammation by reducing macroscopical and microscopical colon injury. In addition, the present study demonstrated that IECm ameliorates TNBS-colitis by promoting antioxidant effect, modulation of cytokines release and restauration of mucus production. The study reinforces the traditional use of the Copaifera malmei leaves infusion to inflammatory gastrointestinal disorders and makes IECm a potential herbal medicine for the treatment of IBD.

Evaluation of the Acute Hepatoprotective Potential of Hydroethanolic Extract of Duranta erecta L. Parts

Liver disease is a major health problem and its treatment is costly in most developing countries with attendant adverse effects. This study aimed at determining the acute hepatoprotective efficacy of Duranta erecta hydroethanolic extracts of leaves, ripe and unripe fruits against CCl₄-, and acetaminophen-induced hepatotoxicity in animals. Materials and Methods. CCl₄ (1 mL/kg body weight in olive oil) and acetaminophen (500 mg/kg b.wt) were used to induce hepatotoxicity in the animals. Animals were treated with extracts at 250 mg/kg b.wt and standard drug, silymarin (100 mg/kg), for 7 days. Hepatoprotective efficacy was assessed by assaying serum biochemical markers such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma-glutamyl transferase (γGT), bilirubin (Bil), antioxidative biomarkers including reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione transferase (GST), superoxide dismutase (SOD), malondialdehyde (MDA), hydrogen peroxidase (H₂0₂), and nitric oxide (NO), as well as histological observations. Results. Exposure of the animals to CCl₄ and acetaminophen resulted in liver injury as evidenced by elevated ALT, AST, ALP, γGT, Bil, MDA, H₂O₂, and NO levels with resultant derangement in liver microarchitecture. Pretreatment with hydroethanolic extracts, particularly ripe fruits of Duranta erecta, led to a reduction in these indicators and an increase in GSH, GPx, GST, and SOD levels. Biochemical data were supported by improvement in liver structure. Conclusion. The findings suggest that hydroethanolic Duranta erecta ripe fruits extract possesses hepatoprotective and antioxidative activities against CCl₄- and acetaminophen-induced toxicity and could be developed as a potent agent for drug-induced liver diseases.

Toxicological evaluation of standardized Kaempferia parviflora extract: Sub-chronic and mutagenicity studies

Kaempferia parviflora (KP), also known as Krachai-dam in Thailand, belongs to the family Zingiberaceae and has been used traditionally to improve blood flow and treat inflammatory, allergic, and gastrointestinal disorders. The objective of this study was to investigate the safety profile of a standardized hydroalcoholic KP rhizome extract via mutagenicity and sub-chronic toxicity evaluations using in vitro and in vivo techniques. The in vitro mutagenicity of KP extract was assessed via reverse mutation tests using Salmonella typhimurium TA98, TA100, TA1535, and TA1537, and Escherichia coli WP2 uvrA. The sub-chronic toxicity profile was evaluated after daily oral administration of KP extract to Sprague-Dawley rats for 90 days. General toxicological parameters were monitored weekly. After the treatment period, blood was collected for hematological and biochemical analyses and certain organs were removed for macroscopic and histopathological analyses. Reverse mutation tests revealed that KP extract did not induce gene mutations at any of the concentrations tested. In the sub-chronic toxicity test, a few changes were observed, including increased salivation in the animals administered high-dose KP extract (249 mg/kg body weight (bw)/day). No toxicologically relevant changes were observed in the biochemical analysis. Sub-chronic administration of KP extract increased platelet levels in animals administered low-dose KP extract (25 mg/kg bw/day). However, the hematological and biochemical parameters remained within normal physiological ranges for the animal species. No toxicological changes were observed in the macroscopic and histopathological analyses performed in this study. These results demonstrate that KP extract is not genotoxic and that 90-day oral administration of the doses tested did not result in toxicity. Therefore, KP extract has a high safety margin for daily use.

Safety Evaluation of a New Traditional Chinese Medical Formula, Ciji-Hua'ai-Baosheng II Formula, in Adult Rodent Models

Background

Ciji-Hua'ai-Baosheng II Formula (CHB-II-F) is a new traditional Chinese medical formula that has been shown to reduce toxicity and side effects of chemotherapy and increase the probability of cancer patient survival. Whether CHB-II-F is safe as an adjunctive therapy for cancer patients receiving chemotherapy has yet to be determined.

Purpose

To evaluate the acute and subchronic toxic effects of CHB-II-F in rodent models.

Methods

In acute toxicity test, 24 Kunming mice were divided into 2 groups: untreated control and CHB-II-F 1.05 g/mL (31.44 g/kg) treated group. Treatment was administered to the treated group 3 times a day for 14 days. The overall health, adverse reactions, and mortality rate were documented. In subchronic toxicity test, 96 Sprague-Dawley rats were divided into 4 groups: untreated control, high dose CHB-II-F (H) (26.20 g/kg), medium dose CHB-II-F (M) (13. 10 g/kg), and low dose CHB-II-F (L) (6.55 g/kg) [equal to 24.375 g (dried medicinal herb)/kg] treated groups. Treated groups were given the treatments once a day for 4 weeks. The overall health and mortality rate were recorded every day. Body weight and food consumption were measured once a week. Hematologic and biochemical parameters, organ weights, and histopathologic markers were analyzed after 4 weeks. An additional 2 weeks were given as the treatment recovery period before end-point euthanization, and biochemical analyses were performed.

Results

The maximum tolerated dose (MTD) of CHB-II-F on mice was found to be 94.31 g/kg [equal to 351 g (dried medicinal herb)/kg], which is 108 times the human adult dose. In the acute toxicity test, administration of CHB-II-F 31.44 g/kg showed no adverse effect and did not cause mortality. In the subchronic toxicity test, after 4 weeks of treatment, compared to the controls, total cholesterol (TCHO) level, cardiac and splenic indexes, body weights of female rats, and mean corpuscular hemoglobin concentration (MCHC) in the CHB-II-F (H) group were significantly increased; triglyceride (TG) in the CHB-II-F (M) group and liver and splenic indexes in the CHB-II-F (L) group were increased. After the two-week recovery period, biofluid analyses, food consumption, and histopathologic examinations showed no abnormalities.

Conclusion

Administration of CHB-II-F had no obvious adverse effect on the overall health of rodent models. A daily maximum dose of less than 94.31 g/kg or 6.55 g/kg CHB-II-F for 4 continuous weeks was considered safe.

Investigation of Safety Profile of Four Copaifera Species and of Kaurenoic Acid by Salmonella/Microsome Test

Trees of the Copaifera genus are native to the tropical regions of Latin America and Western Africa. Copaifera sp is widely used as a popular medicine and it has various ethnopharmacological indications, including gonorrhea, bronchitis, asthma, skin ulcers, ulcers, sore throat, uterine infections, general inflammations, cancer, and leishmanioses. Kaurenoic acid is a naturally occurring diterpene found in Copaifera and has been used as an anti-inflammatory, treatment of ulcer, leishmaniasis, and cancer. Bearing in mind the fact that the Ames test is an excellent tool to assess the safety of extracts, oils, and phytochemicals isolated from medicinal plants, from it, we evaluate the mutagenic potential of four species, between oleoresins (C. oblongifolia; C. langsdorffii) and leaves extracts (C. lucens; C. multijuga), of the Copaifera genus and also of kaurenoic acid, which is one of its major compounds. The results showed that the Copaifera spp. and kaurenoic acid did not induce an increase in the number of revertant colonies, without mutagenic effect in experiments, in the all concentrations evaluated by Ames test. The results obtained in our study support the safe use of the Copaifera genus medicinal plants selected and of kaurenoic acid.