Acute Oral, Subacute, and Developmental Toxicity Profiling of Naphthalene 2-Yl, 2-Chloro, 5-Nitrobenzoate: Assessment Based on Stress Response, Toxicity, and Adverse Outcome Pathways

Benzimidazole-based structure optimization to discover novel anti-gastric cancer agents targeting ROS/MAPK pathway

Given the malignancy of gastric cancer, developing highly effective and low-toxic targeted drugs is essential to prolong patient survival and improve patient outcomes. In this study, we conducted structural optimizations based on the benzimidazole scaffold. Notably, compound 8 f presented the most potent antiproliferative activity in MGC803 cells and induced cell cycle arrest at the G0/G1 phase. Further mechanistic studies demonstrated that compound 8 f caused the apoptosis of MGC803 cells by elevating intracellular reactive oxygen species (ROS) levels and activating the mitogen-activated protein kinase (MAPK) signaling pathway, accompanied by corresponding markers change. In vivo investigations additionally validated the inhibitory effect of compound 8 f on tumor growth in xenograft models bearing MGC803 cells without obvious toxicity. Our studies suggest that compound 8 f holds promise as a potential and safe lead compound for developing anti-gastric cancer agents.

New insights of the application of water or ethanol-water plant extract rich in active compounds in food

Plants are recognized as natural sources of antioxidants (e.g., polyphenols, flavonoids, vitamins, and other active compounds) that can be extracted by green solvents like water, ethanol, or their binary mixtures. Plant extracts are becoming more used as food additives in various food systems due to their antioxidant abilities. Their application in food increases the shelf life of products by preventing undesirable changes in nutritional and sensory properties, such as the formation off-flavors in lipid-rich food. This review summarizes the most recent literature about water or ethanol-water plant extracts used as flavors, colorings, and preservatives to fortify food and beverages. This study is performed with particular attention to describing the benefits of plant extract-fortified products such as meat, vegetable oils, biscuits, pastries, some beverages, yogurt, cheese, and other dairy products. Antioxidant-rich plant extracts can positively affect food safety by partially or fully replacing synthetic antioxidants, which have lately been linked to safety and health issues such as toxicological and carcinogenic consequences. On the other hand, the limitations and challenges of using the extract in food should be considered, like stability, level of purity, compatibility with matrix, price, sensory aspects like distinct taste, and others. In the future, continuous development and a tendency to use these natural extracts as food ingredients are expected, as indicated by the number of published works in this area, particularly in the past decade.

Revealing the most effective anticonvulsant part of Malvaviscus arboreus Dill. Ex Cav. and its acute and sub-acute toxicity

ETHNOPHARMACOLOGY RELEVANCE

Different parts of Malvaviscus arboreus Dill. Ex Cav. (M. arboreus) are traditionally used in the West Region of Cameroon to treat many diseases, including epilepsy.

AIM OF THE STUDY

To determine which part of M. arboreus offers the best anticonvulsant effect, and to assess the acute and sub-acute toxicity of the part of interest.

MATERIALS AND METHODS

the anticonvulsant effect of the aqueous lyophilisate of the decoction of flowers, leaves, stems and roots of M. arboreus at various doses was evaluated and compared on the model of acute epileptic seizures induced by pentylenetetrazole (PTZ) (70 mg/kg), injected 1 h after oral administration of the various extracts. Out of these plant parts, the leaves were then selected to prepare the hydroethanolic extract and its anticonvulsant effect against PTZ at the doses of 122.5, 245 and 490 mg/kg, as well as its acute toxicity were compared with those of the aqueous lyophilisate of the leaves. The anticonvulsant effect of the aqueous lyophilisate of M. arboreus leaves was further evaluated on models of acute epileptic seizures induced by picrotoxin (PIC) (7.5 mg/kg), strychnine (STR) (2.5 mg/kg) and pilocarpine (350 mg/kg). The 28 days sub-acute toxicity, as well as the quantitative phytochemistry and the in vitro antioxidant potential (FRAP, DPPH, ABTS+) of the aqueous lyophilisate of the leaves of M. arboreus were also evaluated.

RESULTS

M. arboreus leaves showed the best anticonvulsant effect and the aqueous lyophilisate was the best extract. The latter significantly protected the animals against convulsions induced by PTZ (71.43%) (p < 0.01), PIC (57.14%) (p < 0.05) and STR (42%) and had no effect on pilocarpine-induced seizures. Furthermore, it showed no acute or sub-acute toxicity, and revealed a high content of flavonoids, saponins, tannins and alkaloids, and antioxidant activity in vitro.

CONCLUSION

The aqueous lyophilisate of the leaves of M. arboreus offers the best anticonvulsant effect on the extraction solvent used, and it would act mainly via a potentiation of the inhibitory systems of the brain (GABA, Glycine). In addition, its richness in bioactive compounds gives it an antioxidant potential, and it is not toxic in acute and sub-acute toxicity. All this justifies at least in part its empirical uses, and makes M. arboreus a candidate for the alternative treatment of epilepsy.

Anti-arthritic and toxicological evaluation of ethanolic extract of Alternanthera bettzickiana in rats

In many developing countries, medicinal plants have long been used for therapeutic purposes due to their low cost and toxicity. This study evaluated the safety and anti-arthritic potential of Alternanthera bettzickiana ethanolic extract (ABEE). Acute oral toxicity (OECD 425) was tested in the safety evaluation. A limit test was used to identify the LD50 value. For an acute oral toxicity study a dose of 2000 mg/kg of ABEE was given orally to the treatment group, and the control group received distilled water at a rate of 10 ml/kg. Biochemical, hematological, and histopathological analyses were performed after 14 days. A formaldehyde 2% w/v solution was injected via i.p. to rats of all groups to prepare the arthritic model. Five groups were divided into control (D.H2O), standard (Diclofenac), and three groups receiving the plant extract at dose levels of 125 mg/kg, 250 mg/kg, and 500 mg/kg respectively. Treatment was continued for 10 days. Paw diameter and hematological and biochemical variables were quantified. ELISA was performed for the estimation of inflammatory cytokines. In the acute oral toxicity study, no mortality or morbidity were observed, so the LD50 of this plant was greater than 2000 mg/kg. ABEE decreased the paw diameter with the restoration of hematological and biochemical changes. SOD and CAT levels were increased while decreasing the MDA, NO, TNF-α, and IL-6 levels in arthritic rats. It is concluded that the use of A. bettzickiana has low toxicity, and it can be used for the treatment of arthritis.

Antidiabetic effects of Brugmansia aurea leaf extract by modulating the glucose levels, insulin resistance, and oxidative stress mechanism

Background

Ethnopharmacological relevance: Brugmansia, a genus of the Solanaceae family, has historically been utilized in many different parts of the world as an anti-inflammatory for treating skin infections, wounds, and bodily aches and pains. The current study aimed to investigate the potential benefits of a methanolic extract of Brugmansia aurea in the management of diabetes and underlying complications in alloxanized-induced diabetic rats.

Materials and methods

Animals were divided into nine groups (n = 6). Four groups received different standard oral hypoglycemic agents; three groups received 100, 200, and 400 mg/kg of B. aurea leaf extract for six consecutive weeks, and the remaining two were normal and disease control groups. All groups received alloxan (150 mg/kg) except for the normal control. Only those animals whose glucose levels were raised to 200 mg/dl were selected for the study. After a 6-week dosage period, various biochemical parameters, as well as HbA1c, antioxidant profile, oral glucose tolerance test (OGTT), insulin sensitivity, histopathology, and insulin resistance, were measured and compared with the untreated diabetic group.

Results

Brugmansia aurea leaf extract at a dose of 400 mg/kg showed potent antidiabetic activity by reducing blood glucose levels (p < 0.001) after 6 weeks of treatment. OGTT data showed that B. aurea exhibited significant (p < 0.001) glucose tolerance by significantly reducing blood glucose levels in just 2 h post-treatment. Other tests showed that plant extract significantly increased (p < 0.001) insulin sensitivity and decreased (p < 0.001) insulin resistance. The biochemical profile showed reduced triglyceride and cholesterol, while the antioxidant profile showed restoration of antioxidant enzymes in the pancreas, kidney, and liver tissues of treated rats.

Conclusion

The present study indicated that crude extracts of B. aurea increase insulin sensitivity and reduce hyperlipidemia in diabetic rats, which rationalizes the traditional medicinal use of this plant as an antidiabetic agent.

Acute, chronic, and genotoxic studies on the protopine total alkaloids of the Macleaya cordata (willd.) R. Br. in rodents

The protopine alkaloids are widely distributed within the opium poppy family and have a wide range of pharmacological effects. MPTA is a product of the protopine total alkaloids extracted from the Macleaya cordata (Willd.) R. Br. Previously, we reported good anti-inflammatory activity of MPTA as well as oral acute and sub-chronic toxicity studies in rats. In order to perform a systematic toxicological safety assessment of MPTA, oral acute toxicity, genotoxicity (bone marrow cell chromosome aberration test, sperm abnormality test, bone marrow cell micronucleus test, and rat teratogenicity test), and chronic toxicity in mice were performed in this study. In the oral acute toxicity test, the LD₅₀ in ICR mice was 481.99 mg/kg, with 95% confidence limits ranging from 404.27 to 574.70 mg/kg. All three mutagenicity tests tested negative in the range of 60.25–241.00 mg/kg. The results of the teratogenicity test in rats showed no reproductive or embryonic developmental toxicity at only 7.53 mg/kg, which can be considered as a no observed effect level (NOEL) for the teratogenicity test. Therefore, MPTA is safe for use at the doses tested, but attention should be paid to the potential risk to pregnant animals and the safety evaluation and toxicity mechanisms in target animals should be further investigated.

Phytochemical and toxicological evaluation of Zephyranthes citrina

Drugs obtained from medicinal plants have always played a pivotal role in the field of medicine and to identify novel compounds. Safety profiling of plant extracts is of utmost importance during the discovery of new biologically active compounds and the determination of their efficacy. It is imperative to conduct toxicity studies before exploring the pharmacological properties and perspectives of any plant. The present work aims to provide a detailed insight into the phytochemical and toxicological profiling of methanolic extract of Zephyranthes citrina (MEZ). Guidelines to perform subacute toxicity study (407) and acute toxicity study (425) provided by the organization of economic cooperation and development (OECD) were followed. A single orally administered dose of 2000 mg/kg to albino mice was used for acute oral toxicity testing. In the subacute toxicity study, MEZ in doses of 100, 200, and 400 mg/kg was administered orally, consecutive for 28 days. Results of each parameter were compared to the control group. In both studies, the weight of animals and their selected organs showed consistency with that of the control group. No major toxicity or organ damage was recorded except for some minor alterations in a few parameters such as in the acute study, leukocyte count was increased and decreased platelet count, while in the subacute study platelet count increased in all doses. In the acute toxicity profile liver enzymes Alanine aminotransferase (ALT), as well as, aspartate aminotransferase (AST) were found to be slightly raised while alkaline phosphatase (ALP) was decreased. In subacute toxicity profiling, AST and ALT were not affected by any dose while ALP was decreased only at doses of 200 and 400 mg/kg. Uric acid was raised at a dose of 100 mg/kg. In acute toxicity, at 2000 mg/kg, creatinine and uric acid increased while urea levels decreased. Therefore, it is concluded that the LD₅₀ of MEZ is more than 2000 mg/kg and the toxicity profile of MEZ was generally found to be safe.