Enantiomeric trans β-aryl-δ-iodo-γ-lactones derived from 2,5-dimethylbenzaldehyde induce apoptosis in canine lymphoma cell lines by downregulation of anti-apoptotic Bcl-2 family members Bcl-xL and Bcl-2

Antioxidants activities of phytochemicals perspective modulation of autophagy and apoptosis to treating cancer

The study of chemicals extracted from natural sources should be encouraged due to the significant number of cancer deaths each year and the financial burden imposed by this disease on society. The causes of almost all cancers involve a combination of lifestyle, environmental factors, and genetic and inherited factors. Modern medicine researchers are increasingly interested in traditional phytochemicals as they hold potential for new bioactive compounds with medical applications. Recent publications have provided evidence of the antitumor properties of phytochemicals, a key component of traditional Chinese medicine, thereby opening new avenues for their use in modern medicine. Various studies have demonstrated a strong correlation between apoptosis and autophagy, two critical mechanisms involved in cancer formation and regulation, indicating diverse forms of crosstalk between them. Phytochemicals have the ability to activate both pro-apoptotic and pro-autophagic pathways. Therefore, understanding how phytochemicals influence the relationship between apoptosis and autophagy is crucial for developing a new cancer treatment strategy that targets these molecular mechanisms. This review aims to explore natural phytochemicals that have demonstrated anticancer effects, focusing on their role in regulating the crosstalk between apoptosis and autophagy, which contributes to uncontrolled tumor cell growth. Additionally, the review highlights the limitations and challenges of current research methodologies while suggesting potential avenues for future research in this field.

Lipase-mediated Baeyer-Villiger oxidation of benzylcyclopentanones in ester solvents and deep eutectic solvents

This work presents the chemo-enzymatic Baeyer-Villiger oxidation of α-benzylcyclopentanones in ester solvents as well as deep eutectic solvents (DES). In the first part of the work the effect of selected reaction conditions on the reaction rate was determined. The oxidation process was most effective in ethyl acetate at 55 °C, with the use of lipase B from Candida antarctica immobilized on acrylic resin and UHP as oxidant. Ultimately, these preliminary studies prompted the development of an effective method for the implementation of lipase-mediated Baeyer-Villiger oxidation of benzylcyclopentanones in DES. The highest conversion was indicated when the oxidizing agent was a component of DESs (minimal DESs). The fastest conversion of ketones to lactones was observed in a mixture of choline chloride with urea hydrogen peroxide. In this case, after 3 days, the conversion of the ketones to lactones products exceeded 92% for all substrates. As a result, two new lactones were obtained and fully characterized by spectroscopic data.

SCP-7, a germacrane-type sesquiterpene lactone derivative, induces ROS-mediated apoptosis in NSCLC cells in vitro and in vivo

Scabertopin (SCP), an abundant germacrane-type sesquiterpene lactone (SLC) isolated from Elephantopus scaber, was selected as a reference compound for modification and evaluation as anticancer agents for non-small cell lung cancer (NSCLC) treatment. All derivatives (SCP-1-SCP-13) except for SCP-3 showed potential inhibitory effect (IC₅₀ 5.2-9.7 μM) against A549 cells. The most promising compound SCP-7 also showed good cytotoxic activity against another two NSCLC cell lines (H1299 and H460), with IC₅₀ value of 4.4 and 8.9 μM, respectively. Furthermore, SCP-7 could induce apoptotic cell death that was associated with the increased reactive oxygen species (ROS) generation, the loss of mitochondrial membrane potential, Bcl-2 family proteins modulation, caspases-3 and PARP cleavage. In addition, SCP-7 also inhibited cell growth by increasing Bax expression and reducing the Ki-67 positive cells in vivo, but there were no obvious toxic and side effects on internal organs. Mechanistically, PharmMapper, molecular docking and Western blot analysis revealed that SCP-7 might interact with the epidermal growth factor receptor (EGFR) and inhibit its expression in lung cancer cells. Together, above results suggest further effective application of SCP-7 as a potential anti-tumor agent in the treatment of NSCLC.

Inhibitory regulation of purple sweet potato polysaccharide on the hepatotoxicity of tri-(2,3-dibromopropyl) isocyanate

Tri-(2,3-dibromopropyl) isocyanate (TBC), a new emerged persistent organic pollutant, is widely used in fields of flame retardant, textile, rubber and plastic with strong hepatotoxicity. Purple Sweet Potato Polysaccharide (PSPP) has antioxidant and hepatoprotective effects. This study aims to answer the scientific question whether PSPP has a protective effect on TBC induced liver injury. The effect of PSPP on the apoptosis of HepG2 cells was detected by MTT assay, the morphological changes were observed by morphological observation, and the apoptosis rate was determined by flow cytometry. The apoptotic genes were detected by qPCR assay, the relevant protein express was detected by western blot. The correlation between proteins and genes in the apoptosis pathway of HepG2 cells was calculated. To further reveal the apoptosis mechanism of TBC hepatotoxicity in vivo, 19 target genes and 14 apoptotic related proteins of inhibiting apoptosis via death receptor and mitochondria were discussed, all the above results proved that PSPP had protective effect on liver injury induced by TBC. This study not only provided a scientific basis for clarifying the mechanism of TBC hepatotoxicity and the protective effect of PSPP, but also generated the new point and method in terms of the prevention in advance and early intervention of diseases caused by environmental pollution.

Methoxy-Substituted γ-Oxa-ε-Lactones Derived from Flavanones-Comparison of Their Anti-Tumor Activity In Vitro

Background: The study investigated four flavanone-derived γ-oxa-ε-lactones: a parent unsubstituted compound and its three derivatives with the methoxy group in positions 2′, 4′ and 8. Our objective was to find out if the introduction of the methoxy group into the aromatic ring affects in vitro anti-tumor potency of the investigated lactones. Methods: Cytotoxic and pro-apoptotic effects were assessed with cytometric tests with propidium iodide, annexin V, and Western blot techniques. We also investigated potential synergistic potency of the tested lactones and glucocorticoids in canine lymphoma/leukemia cell lines. Results: The tested flavanone-derived lactones showed anti-cancer activity in vitro. Depending on its location, the methoxy group either increased or decreased cytotoxicity of the derivatives as compared with the parent compound. The most potent lactone was the one with the methoxy group at position 4′ of the B ring (compound 3), and the weakest activity was observed when the group was located at C-8 in the A ring. A combination of the lactones with glucocorticoids confirmed their synergy in anti-tumor activity in vitro. Conclusions: Methoxy-substituted flavanone-derived lactones effectively kill canine lymphoma/leukemia cells in vitro and, thanks to their synergistic action with glucocorticoids, may potentially be applied in the treatment of hematopoietic cancers.

Biological Activity of Selected Natural and Synthetic Terpenoid Lactones

Terpenoids with lactone moieties have been indicated to possess high bioactivity. Certain terpenoid lactones exist in nature, in plants and animals, but they can also be obtained by chemical synthesis. Terpenoids possessing lactone moieties are known for their cytotoxic, anti-inflammatory, antimicrobial, anticancer, and antimalarial activities. Moreover, one terpenoid lactone, artemisinin, is used as a drug against malaria. Because of these abilities, there is constant interest in new terpenoid lactones that are both isolated and synthesized, and their biological activities have been verified. In some cases, the activity of the terpenoid lactone is specifically connected to the lactone moiety. Recent works have revealed that new terpenoid lactones can demonstrate such functions and are thus considered to be potential active agents against many diseases.

Biotechnological Approach for the Production of Enantiomeric Hydroxylactones Derived from Benzaldehyde and Evaluation of Their Cytotoxic Activity

The β-aryl-δ-halo-γ-lactones are known for their antiproliferative activity towards numerous cancer cell lines. The aim of this study was to obtain in the biotransformation process new β-aryl-δ-hydroxy-γ-lactones and compare their activity with the antiproliferative activity of parent compounds. The racemic cis-5-(1-iodoethyl)-4-phenyldihydrofuran-2-one as well as separate enantiomers were transformed in fungal cultures. Among ten tested biocatalysts, three (Absidia cylindrospora AM336, Absidia glauca AM254, and Fusarium culmorum AM10) were able to catalyze the hydrolytic dehalogenation process. The biotransformations processes were highly stereoselective and enantiomerically pure hydroxylactones were obtained (ee ≥ 99%). The iodo- and hydroxylactone enantiomers were subjected to cytotoxic activity evaluation on canine leukemia and lymphoma cell lines. The iodolactones exhibited higher biological potential towards tested cell lines than hydroxylactones. Higher cytotoxic potential was also characteristic for (+)-(4S,5S,6R)-enantiomer of iodolactone compared to its antipode.

Chrysin attenuates traumatic brain injury-induced recognition memory decline, and anxiety/depression-like behaviors in rats: Insights into underlying mechanisms

RATIONALE

Cortical and hippocampal neuronal apoptosis and neuroinflammation are associated with behavioral deficits following traumatic brain injury (TBI).

OBJECTIVES

The present study was designed to investigate the potential protective effects of flavonoid chrysin against TBI-induced vestibulomotor impairment, exploratory/locomotor dysfunctions, recognition memory decline, and anxiety/depression-like behaviors, as well as the verified possible involved mechanisms.

METHODS

Chrysin (25, 50, or 100 mg/kg/day; P.O.) was administered to rats immediately after diffuse TBI induction, and it was continued for 3 or 14 days. Behavioral functions were assessed by employing standard behavioral paradigms at scheduled points in time. Three days post-TBI, inflammation status was assayed in both cerebral cortex and hippocampus using ELISA kits. Moreover, apoptosis and expression of Bcl-2 family proteins were examined by TUNEL staining and immunohistochemistry, respectively.

RESULTS

The results indicated that treatment with chrysin improved vestibulomotor dysfunction, ameliorated recognition memory deficit, and attenuated anxiety/depression-like behaviors in the rats with TBI. Chrysin treatment also modulated inflammation status, reduced apoptotic index, and regulated Bcl-2 family proteins expression in the brains of rats with TBI.

CONCLUSIONS

In conclusion, the results suggest that chrysin could be beneficial for protection against TBI-associated behavioral deficits, owing to its anti-apoptotic and anti-inflammatory properties.

The Role of Bcl-xL Protein Research in Veterinary Oncology

Due to their significant impact on human and animal health, cancer diseases are an area of considerable concern for both human and veterinary medicine. Research on the cancer pathogenesis in companion animals, such as dogs, allows not only for improving canine cancer treatment, but also for translating the results into human oncology. Disruption of apoptosis in tumor-transformed cells is a well-known mechanism leading to the development of cancer. One of the main factors involved in this process are proteins belonging to the B-cell lymphoma 2 (Bcl-2) family, and the imbalance between pro-apoptotic and anti-apoptotic members of this family contributes to the development of cancer. Studies on the function of these proteins, including B-cell lymphoma-extra large (Bcl-xL), have also been intensively conducted in companion animals. The Bcl-xL gene was sequenced and found to share over 99% homology with the human protein. Research showed that the Bcl-2 family plays the same role in human and canine cells, and data from studies in dogs are fully translatable to other species, including humans. The role of this protein family in cancer development was also confirmed. The article presents the current state of knowledge on the importance of the Bcl-xL protein in veterinary oncology.

Chemoenzymatic Synthesis of Enantiomeric, Bicyclic δ-Halo-γ-lactones with a Cyclohexane Ring, Their Biological Activity and Interaction with Biological Membranes

Starting from 1-acetyl-1-cyclohexene, three enantiomeric pairs (ee ≥99%) of bicyclic δ-halo-γ-lactones with cyclohexane ring were obtained in five-step synthesis. The key stereochemical steps were lipase-catalyzed kinetic resolution of racemic 1-(cyclohex-1-en-1-yl) ethanol followed by transfer of chirality to ethyl 2-(2-ethylidenecyclohexyl) acetate in the Johnson-Claisen rearrangement. Synthesized halolactones exhibited antiproliferative activity towards canine B-cell leukemia cells (GL-1) and canine B-cell chronic leukemia cells (CLB70) and the most potent (IC₅₀ 18.43 ± 1.46 μg/mL against GL-1, IC₅₀ 11.40 ± 0.40 μg/mL against CLB70) comparable with the control etoposide, was (1R,6R,1'S)-1-(1'-chloroethyl)-9- oxabicyclo[4.3.0]nonan-8-one (8b). All halolactones did not have a toxic effect on erythrocytes and did not change the fluidity of membranes in the hydrophobic region of the lipid bilayer. Only weak changes in the hydrophilic area were observed, like the degree of lipid packing and associated hydration. The racemic halolactones were also tested for their antimicrobial properties and found to exhibit selectivity towards bacteria, in particular, towards Proteus mirabilis ATCC 35659.

Therapeutic effects of chrysin in a rat model of traumatic brain injury: A behavioral, biochemical, and histological study

AIMS

Oxidative stress and apoptosis have major roles in the progression of traumatic brain injury (TBI)-associated motor and cognitive deficits. The present study was aimed to elucidate the putative effects of chrysin, a natural flavonoid compound, against TBI-induced motor and cognitive dysfunctions and possible involved mechanisms.

MAIN METHODS

Chrysin (25, 50 or 100 mg/kg) was orally administered to rats starting immediately following TBI induction by Marmarou's weight-drop technique and continuously for 3 or 14 days. Neurological functions, motor coordination, learning and memory performances, histological changes, cell apoptosis, expression of pro- and anti-apoptotic proteins, and oxidative status were assayed at scheduled time points after experimental TBI.

KEY FINDINGS

The results indicated that treatment with chrysin improved learning and memory disabilities in passive avoidance task, and ameliorated motor coordination impairment in rotarod test after TBI. These beneficial effects were accompanied by increased the concentrations of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione (GSH), decreased malondialdehyde (MDA) content, prevented neuronal loss, diminished apoptotic index, elevated the expression of anti-apoptotic Bcl-2 protein, and reduced the expression of pro-apoptotic Bax protein in the cerebral cortex and hippocampus tissues.

SIGNIFICANCE

Our findings suggest that both anti-oxidative and anti-apoptotic properties of chrysin (especially in the dose of 100 mg/kg) are possible mechanisms that improve cognitive/motor deficits and prevent neuronal cell death after TBI.

Microbial Asymmetric Functionalization of β-Cyclocitral-Derived Tetramethyl-Substituted γ-Lactone

Searching for the new anticancer compounds we prepared three new β-cyclocitral-derived hydroxyl-γ-lactones by microbial hydroxylation of tetramethyl-substituted bicyclic γ-lactone. The substrate was transformed by the enzymatic system of filamentous fungi. Three out of fifteen strains were selected as effective biocatalysts (Fusarium culmorum AM10, Armillaria mellea AM296, Trametes versicolor AM536). The hydroxylation processes were not only regioselective but also stereoselective. The hydroxylation products of each secondary carbon atom in the cyclohexane ring were obtained by the application of the selected fungal strains. The Fusarium culmorum AM10 introduced the hydroxy function at C-3 and C-4, Armillaria mellea AM296 incorporated the hydroxy function at C-3 and C-5 and Trametes versicolor AM536 transformed the substrate to the mixture of C-3, C-4 and C-5 hydroxylactones. The hydroxylactones obtained were enantiomericaly enriched (ee values in the range 17–99%). The in vitro antiproliferative activities of the functionalization products were also evaluated. Regardless of the hydroxy substituent location all tested lactones exhibited similar, significant activity towards selected cancer cell lines (IC₅₀ in the range 22.8–33.9 µg/mL).

Preparation of Enantiomeric β-(2',5'-Dimethylphenyl)Bromolactones, Their Antiproliferative Activity and Effect on Biological Membranes

Three novel enantiomeric pairs of bromolactones possesing a 2,5-dimethylphenyl substituent at the β-position of the lactone ring have been synthesized from corresponding enantiomeric (E)-3-(2',5'-dimethylphenyl)hex-4-enoic acids (4) by kinetically controlled bromolactonization with N-bromosuccinimide (NBS). γ-Bromo-δ-lactones (5) were isolated as the major products. Absolute configurations of stereogenic centers of γ-bromo-δ-lactones (5) were assigned based on X-ray analysis; configurations of cis δ-bromo-γ-lactones (6) and trans δ-bromo-γ-lactones (7) were determined based on mechanism of bromolactonization. Synthesized compounds exhibited significant antiproliferative activity towards the four canine cancer cell lines (D17, CLBL-1, CLB70, and GL-1) and one human cancer line (Jurkat). Classifying the compounds in terms of activity, the most active were enantiomers of trans δ-bromo-γ-lactones (7) followed by enantiomers of cis isomer (6) and enantiomeric γ-bromo-δ-lactones (5). Higher activity was observed for all stereoisomers with S configuration at C-4 in comparison with their enantiomers with 4R configuration. Synthesized compounds did not induce hemolysis of erythrocytes. The results of the interaction of bromolactones with red blood cell membranes suggest that these compounds incorporate into biological membranes, concentrating mainly in the hydrophilic part of the bilayer but have practically no influence on fluidity in the hydrophobic region. The differences in interactions with the membrane between particular enantiomers were observed only for γ-lactones: stronger interactions were found for enantiomer 4R,5R,6S of cis γ-lactone (6) and for enantiomer 4S,5R,6S of trans γ-lactone (7).