Rapanone, a naturally occurring benzoquinone, inhibits mitochondrial respiration and induces HepG2 cell death

Optimization of Extraction Conditions and Cytotoxic Activity of Rapanone in Comparison to Its Homologue, Embelin

Rapanone is a plant-derived simple alkyl-dihydroxybenzoquinone structurally close to embelin, a well-known cytotoxic agent. The pharmacological characterization of rapanone is still incomplete, and to fill the data gap, a good source for its acquisition is required to conduct further research. This study aimed to optimize the conditions for the extraction of rapanone from the leaves of white-berried Ardisia crenata Sims. For this purpose, three methods were employed: heat reflux (HRE), shaking (SE), and ultrasound-assisted extraction (UAE), and such parameters as the extraction time, solvent, and the number of extractions from the same sample were set as experimental variables. Furthermore, cytotoxic activity toward prostate cancer, thyroid cancer, and colorectal carcinoma cell lines was investigated and compared with doxorubicin and embelin. The most effective and economical method for the extraction of rapanone was shown to be 20 min UAE with ethyl acetate or chloroform. Rapanone exhibited high cytotoxic activity against PC3 (IC₅₀ = 6.50 μg/mL), Du145 (IC₅₀ = 7.68 μg/mL), FTC133 (IC₅₀ = 6.01 μg/mL), 8505C (IC₅₀ = 7.84 μg/mL), and Caco-2 (IC₅₀ = 8.79 μg/mL) cell lines after 24 h and against the HT29 cell line after 48 h (IC₅₀ = 11.67 μg/mL). Furthermore, it revealed a more favorable safety profile than either its homologue, embelin, or doxorubicin. The set of optimal extraction parameters obtained may be utilized for scientific and industrial purposes to achieve the best rapanone yield. Moreover, this benzoquinone revealed a high cytotoxic activity with good selectivity.

Decabromodiphenyl ethane induces male reproductive toxicity by glycolipid metabolism imbalance and meiotic failure

Decabromodiphenyl ethane (DBDPE) is a typical flame retardant found in various electrical and textile items. DBDPE is abundantly available in the surrounding environment and wild animals based on its persistence and bioaccumulation. DBDPE has been shown to cause apoptosis in rat spermatogenic cells, resulting in reproductive toxicity. However, the toxicity of DBDPE on the male reproductive system and the potential mechanisms are still unclear. This study evaluated the effect of DBDPE on the reproductive system in male SD rats and demonstrated the potential mechanisms of reproductive toxicity. DBDPE (0, 5, 50, and 500 mg/kg/day) was administered via gavage to male SD rats for 28 days. DBDPE caused histopathological changes in the testis, reduced sperm quantity and motility, and raised the malformation rate in rats, according to the findings. Furthermore, it caused DNA damage to rat testicular cells. It inhibited the expressions of spermatogenesis-and oogenesis-specific helix-loop-helix transcription factor 1 (Sohlh1), piwi-like RNA-mediated gene silencing 2 (MILI), cyclin-dependent kinase 2 (CDK2), and CyclinA, resulting in meiotic failure, as well as the expressions of synaptonemal complex proteins 1 and 3 (SYCP1 and SYCP3), leading to chromosomal association disorder in meiosis and spermatocyte cycle arrest. Moreover, DBDPE induced glycolipid metabolism disorder and activated mitochondria-mediated apoptosis pathways in the testes of SD rats. The quantity and quality of sperm might be declining due to these factors. Our findings offer further evidence of the harmful impact of DBDPE on the male reproductive system.

The hepatoprotective effects of Pyrus biossieriana buhse leaf extract on tert-butyl hydroperoxide toxicity in HepG2 cell line

OBJECTIVE

In present study, the effects of the leaf extract of Pyrus biossieriana Buhse on tert-Butyl hydroperoxide (t-BHP) induced toxicity in the HepG2 cell line were investigated.

RESULTS

HepG2 cells were exposed to different concentrations of both extract (1.5, 2.0, and 2.5 mg/mL) and t-BHP (100, 150, and 200 μM). The total flavonoid and phenolic contents, the cell viability, lipid peroxidation, NO generation, and the total antioxidant capacity in cell media were assessed. The amount of arbutin was estimated 12.6% of the dry weight of leaves (equivalent to 126 mg/g). Additionally, the amounts of flavonoids and phenols in extract were estimated 119 mg/g and 418 mg/g, respectively. The cells incubated with t-BHP showed a significant decrease in survival (p < 0.001). Preincubation with extract (1.5 mg/mL and 2.0 mg/mL) attenuated the t-BHP toxicity and increased the cell viability in cells exposed even to the highest concentration of t-BHP (200 μM) (p value < 0.001, and p value = 0.035) respectively. Additionally, treatment with extract reduced the cell growth suppression caused by t-BHP. The P. biossieriana Buhse leaf extract at concentrations of 1.5 and 2.0 mg/mL is capable of attenuating t-BHP-induced cytotoxicity in HepG2 cells.

Heliotropium indicum L.: From Farm to a Source of Bioactive Compounds with Therapeutic Activity

This study aimed to summarize the available data on the ethnomedicinal and phytopharmacological activities of Heliotropium indicum L. based on database reports. For this purpose, an up-to-date literature search was carried out in the Google Scholar, Scopus, Springer Link, Web of Science, ScienceDirect, ResearchGate, PubMed, Chem Spider, Elsevier, BioMed Central, and patent offices (e.g., USPTO, CIPO, NPI, Google patents, and Espacenet) for the published materials. The findings suggest that the plant contains many important phytochemicals, including pyrrolizidine alkaloids, indicine, echinitine, supinine, heleurine, heliotrine, lasiocarpine, acetyl indicine, indicinine, indicine N-oxide, cynoglossine, europine N-oxide, heleurine N-oxide, heliotridine N-oxide, heliotrine N-oxide, heliotrine, volatile oils, triterpenes, amines, and sterols. Scientific reports revealed that the herb showed antioxidant, analgesic, antimicrobial, anticancer, antituberculosis, antiplasmodial, anticataract, antifertility, wound healing, antiinflammatory, antinociceptive, antihyperglycemic, anthelmintic, diuretic, antitussive, antiglaucoma, antiallergic, and larvicidal activity. In conclusion, in vitro studies with animal models seem to show the potential beneficial effects of H. indicum against a wide variety of disorders and as a source of phytotherapeutic compounds. However, clinical studies are necessary to confirm the effects observed in animal models, determine the toxicity of the therapeutic dose and isolate the truly bioactive components.

Biguanide-transition metals complexes as potential drug for hyperglycemia treatment

Coordination compounds of Cu(ii), Ni(ii), Co(ii), and Zn(ii) with a type of biguanide (known commercially as metformin) have been synthesized and characterized using spectroscopic techniques (FT-IR, UV/VIS), X-ray diffraction techniques and thermal analysis. For all compounds, single crystals were obtained for single-crystal X-ray diffraction. For the first time, an octahedral cobalt compound with the formula [Co(C₄H₁₁N₅)₃]Cl₂·2H₂O that crystallizes in the monoclinic space group C2/c with one molecule in the asymmetric unit has been obtained. Also, a novel nickel compound with the formula [Ni(C₄H₁₁N₅) (C₄H₁₀N₅)]Cl·H₂O that crystallizes in the monoclinic space group P2₁/c with two molecules in the asymmetric unit was obtained. Finally, we obtained copper and zinc compounds that crystallize in the monoclinic space groups P2₁/n and P2₁/c with the general formula [Cu(C₄H₁₁N₅)₂]Cl₂·H₂O and [Zn(C₄H₁₂N₅)Cl₃], respectively. A structural and supramolecular analysis was developed for all compounds using Hirshfeld surface analysis and electrostatic potential maps. The cell viability of the obtained compounds was evaluated in C2C12 (ATCCCRL-1772™) mouse muscle cells and HepG2 (ATCC HB-8065™) human liver carcinoma cells by the MTT assay to determine the potential of the compounds as new safe drugs. The results demonstrate that the compounds exhibit low cytotoxicity at doses less than 250 μg mL⁻¹ with a cell viability greater than 80%.

Coordination compounds of Cu(ii), Ni(ii), Co(ii), and Zn(ii) with a type of biguanide were obtained and structurally characterized. The new metal-drugs present biological applications as potential drugs for diabetes and metabolic syndrome.