-
Molecules (Basel, Switzerland) Feb 2023The use of dioxygen as an oxidant in fine chemicals production is an emerging problem in chemistry for environmental and economical reasons. In acetonitrile, the...
The use of dioxygen as an oxidant in fine chemicals production is an emerging problem in chemistry for environmental and economical reasons. In acetonitrile, the [(N4Py)Fe] complex, [N4Py--bis(2-pyridylmethyl)--(bis-2-pyridylmethyl)amine] in the presence of the substrate activates dioxygen for the oxygenation of cyclohexene and limonene. Cyclohexane is oxidized mainly to 2-cyclohexen-1-one, and 2-cyclohexen-1-ol, cyclohexene oxide is formed in much smaller amounts. Limonene gives as the main products limonene oxide, carvone, and carveol. Perillaldehyde and perillyl alcohol are also present in the products but to a lesser extent. The investigated system is twice as efficient as the [(bpy)Fe]/O/cyclohexene system and comparable to the [(bpy)Mn]/O/limonene system. Using cyclic voltammetry, it has been shown that, when the catalyst, dioxgen, and substrate are present simultaneously in the reaction mixture, the iron(IV) oxo adduct [(N4Py)Fe=O] is formed, which is the oxidative species. This observation is supported by DFT calculations.
PubMed: 36903486
DOI: 10.3390/molecules28052240 -
Plant Physiology and Biochemistry : PPB Mar 2023Nano-selenium (nano-Se) and melatonin (MT) applications confirmed to boost plant growth and resistance. The mechanism of various ratios of nano-Se and MT foliar...
Nano-selenium (nano-Se) and melatonin (MT) applications confirmed to boost plant growth and resistance. The mechanism of various ratios of nano-Se and MT foliar application postpone the senescence of fresh cut carnation flowers and improve vase life remains unclear. In this study, a combined effect with nano-Se (nano-Se5, 5 mg/L) and MT(MT1, 1 mg/L) was preferable to the control, nano-Se, and MT treatment alone when it came to delaying flower senescence. They enhance the antioxidant ability of carnation flowers by lowering MDA and HO levels, raising SOD and POD concentrations, and lowering procyanidins biosynthesis (catechins and epicatechin). Inducing the biosynthesis of hormonal compounds (salicylic acid, jasmonic acid, and abscisic acid), their combination also boosted the growth of carnations. Biofortification with nano-Se and MT substantially increased the amounts of key lignin biosynthesis pathway metabolites (L-phenylalanine, p-hydroxycinnamic acid, p-coumaric acid, perillyl alcohol, p-Coumaryl alcohol, and cinnamic acid), which may increase stem cellular thickness and facilitate water absorption and transmission. The study hypothesizes that nano-Se and MT synergistic applications act as a new efficient non-toxic preservative to extend the vase life and improve the decorative value of carnations.
Topics: Melatonin; Dianthus; Flowers; Hydrogen Peroxide; Antioxidants; Selenium
PubMed: 36893613
DOI: 10.1016/j.plaphy.2023.02.033 -
Antibiotics (Basel, Switzerland) Feb 2023The treatment of bacterial infections has been troubled by the increased resistance to antibiotics, instigating the search for new antimicrobial therapies....
The treatment of bacterial infections has been troubled by the increased resistance to antibiotics, instigating the search for new antimicrobial therapies. Phytochemicals have demonstrated broad-spectrum and effective antibacterial effects as well as antibiotic resistance-modifying activity. In this study, perillyl alcohol and hydrocinnamic acid were characterized for their antimicrobial action against . Furthermore, dual and triple combinations of these molecules with the antibiotics chloramphenicol and amoxicillin were investigated for the first time. Perillyl alcohol had a minimum inhibitory concentration (MIC) of 256 µg/mL and a minimum bactericidal concentration (MBC) of 512 µg/mL. Hydrocinnamic acid had a MIC of 2048 µg/mL and an MBC > 2048 µg/mL. Checkerboard and time-kill assays demonstrated synergism or additive effects for the dual combinations chloramphenicol/perillyl alcohol, chloramphenicol/hydrocinnamic acid, and amoxicillin/hydrocinnamic acid at low concentrations of both molecules. Combenefit analysis showed synergism for various concentrations of amoxicillin with each phytochemical. Combinations of chloramphenicol with perillyl alcohol and hydrocinnamic acid revealed synergism mainly at low concentrations of antibiotics (up to 2 μg/mL of chloramphenicol with perillyl alcohol; 0.5 μg/mL of chloramphenicol with hydrocinnamic acid). The results highlight the potential of combinatorial therapies for microbial growth control, where phytochemicals can play an important role as potentiators or resistance-modifying agents.
PubMed: 36830271
DOI: 10.3390/antibiotics12020360 -
Archives of Biochemistry and Biophysics Mar 2023Rhodococcus globerulus is a metabolically active organism that has been shown to utilise eucalypt oil as its sole source of carbon and energy. This oil includes...
Rhodococcus globerulus is a metabolically active organism that has been shown to utilise eucalypt oil as its sole source of carbon and energy. This oil includes 1,8-cineole, p-cymene and limonene. Two identified and characterised cytochromes P450 (P450s) from this organism initiate the biodegradation of the monoterpenes 1,8-cineole (CYP176A1) and p-cymene (CYP108N12). Extensive characterisation has been completed for CYP176A1 and it has been successfully reconstituted with its immediate redox partner, cindoxin, and E. coli flavodoxin reductase. Two putative redox partner genes are encoded in the same operon as CYP108N12 and here the isolation, expression, purification, and characterisation of its specific [2Fe-2S] ferredoxin redox partner, cymredoxin is presented. Reconstitution of CYP108N12 with cymredoxin in place of putidaredoxin, a [2Fe-2S] redox partner of another P450, improves both the rate of electron transfer (from 13 ± 2 to 70 ± 1 μM NADH/min/μM CYP108N12) and the efficiency of NADH utilisation (the so-called coupling efficiency increases from 13% to 90%). Cymredoxin improves the catalytic ability of CYP108N12 in vitro. Aldehyde oxidation products of the previously identified substrates p-cymene (4-isopropylbenzaldehyde) and limonene (perillaldehyde) were observed in addition to major hydroxylation products 4-isopropylbenzyl alcohol and perillyl alcohol respectively. These further oxidation products had not previously been seen with putidaredoxin supported oxidation. Furthermore, when supported by cymredoxin CYP108N12 is able to oxidise a wider range of substrates than previously reported. These include o-xylene, α-terpineol, (-)-carveol and thymol yielding o-tolylmethanol, 7-hydroxyterpineol, (4R)-7-hydroxycarveol and 5-hydroxymethyl-2-isopropylphenol, respectively. Cymredoxin is also capable of supporting CYP108A1 (P450) and CYP176A1 activity, allowing them to catalyse the hydroxylation of their native substrates α-terpineol to 7-hydroxyterpineol and 1,8-cineole to 6β-hydroxycineole respectively. These results indicate that cymredoxin not only improves the catalytic capability of CYP108N12 but can also support the activity of other P450s and prove useful for their characterisation.
Topics: Eucalyptol; Ferredoxins; Escherichia coli; Limonene; NAD; Cytochrome P-450 Enzyme System; Oxidation-Reduction
PubMed: 36801262
DOI: 10.1016/j.abb.2023.109549 -
PNAS Nexus May 2022MEK inhibitors are among the most successful molecularly targeted agents used as cancer therapeutics. However, to treat cancer more efficiently, resistance to MEK...
MEK inhibitors are among the most successful molecularly targeted agents used as cancer therapeutics. However, to treat cancer more efficiently, resistance to MEK inhibitor-induced cell death must be overcome. Although previous genetic approaches based on comprehensive gene expression analysis or RNAi libraries led to the discovery of factors involved in intrinsic resistance to MEK inhibitors, a feasible combined treatment with the MEK inhibitor has not yet been developed. Here, we show that a chemoproteoinformatics approach identifies ligands overcoming the resistance to cell death induced by MEK inhibition as well as the target molecule conferring this resistance. First, we used natural products, perillyl alcohol and sesaminol, which induced cell death in combination with the MEK inhibitor trametinib, as chemical probes, and identified ribosomal protein S5 (RPS5) as their common target protein. Consistently, trametinib induced cell death in RPS5-depleted cancer cells via upregulation of the apoptotic proteins BIM and PUMA. Using molecular docking and molecular dynamics (MD) simulations, we then screened FDA- and EMA-approved drugs for RPS5-binding ligands and found that acetylsalicylic acid (ASA, also known as aspirin) directly bound to RPS5, resulting in upregulation of BIM and PUMA and induction of cell death in combination with trametinib. Our chemoproteoinformatics approach demonstrates that RPS5 confers resistance to MEK inhibitor-induced cell death, and that aspirin could be repurposed to sensitize cells to MEK inhibition by binding to RPS5.
PubMed: 36713317
DOI: 10.1093/pnasnexus/pgac059 -
Naunyn-Schmiedeberg's Archives of... Jun 2023Allergic asthma is an inflammatory and chronic condition, which is the most common asthma phenotype. It is usually defined by sensitivity to environmental allergens and...
Allergic asthma is an inflammatory and chronic condition, which is the most common asthma phenotype. It is usually defined by sensitivity to environmental allergens and leads to the narrowing of the airways. Around 300 million individuals are suffering from asthma worldwide. The purpose of the current research was to evaluate the effect of perillyl alcohol (PA) on oxidative stress and inflammation parameters in rats with allergic asthma. Experimental asthma was induced by ovalbumin (OVA) sensitization and inhalation in five groups of rats including control, asthma, asthma + vehicle, asthma + PA, and asthma + dexamethasone (Dexa). PA (50 mg/kg) or Dexa (2.5 mg/kg) were administered intraperitoneally for seven consecutive days following asthma induction. Histopathological evaluation was performed via hematoxylin and eosin (H&E) and Masson's trichrome staining. The enzyme-linked immunosorbent assay (ELISA) was used for the evaluation of the cytokine levels, including tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, IL-17, and IL-10, as well as oxidative stress biomarkers including reactive oxygen species (ROS), superoxide dismutase (SOD), malondialdehyde (MDA), total antioxidant capacity (TAC), and glutathione peroxidase (GPx) in the lung tissue and bronchoalveolar lavage fluid (BALF). Real-time polymerase chain reaction (PCR) was utilized for assessing the mRNA expression of FOXP3 and GATA3 and western blot analysis was used for the measurement of nuclear factor kappa B (NF-κB) protein expression. PA and Dexa decreased the pathological alterations and the expression levels of inflammatory factors (cytokines, GATA3, and NF-κB) in the lung tissue and BALF of asthmatic rats. PA restored GPx, SOD, and TAC levels and reduced ROS, MDA, nitrite, and total protein in the lung and BALF. Overall, our findings demonstrated that PA can be used as a therapeutic agent in asthma patients, but it is essential to monitor its effects in future clinical studies.
Topics: Rats; Animals; Mice; NF-kappa B; Reactive Oxygen Species; Asthma; Lung; Cytokines; Bronchoalveolar Lavage Fluid; Superoxide Dismutase; Oxidative Stress; Ovalbumin; Disease Models, Animal; Mice, Inbred BALB C
PubMed: 36707429
DOI: 10.1007/s00210-023-02398-5 -
Cancers Dec 2022Many patients with acute myeloid leukemia (AML) are still dying from this disease. In the past, the alkylating agent temozolomide (TMZ) has been investigated for AML and...
Many patients with acute myeloid leukemia (AML) are still dying from this disease. In the past, the alkylating agent temozolomide (TMZ) has been investigated for AML and found to be partially effective; however, the presence of O6-methylguanine DNA methyltransferase (MGMT; a DNA repair enzyme) in tumor cells confers profound treatment resistance against TMZ. We are developing a novel anticancer compound, called NEO212, where TMZ was covalently conjugated to perillyl alcohol (a naturally occurring monoterpene). NEO212 has revealed robust therapeutic activity in a variety of preclinical cancer models, including AML. In the current study, we investigated its impact on a panel of human AML cell lines and found that it exerted cytotoxic potency even against MGMT-positive cells that were highly resistant to TMZ. Furthermore, NEO212 strongly stimulated the expression of a large number of macrophage-associated marker genes, including CD11b/ITGAM. This latter effect could not be mimicked when cells were treated with TMZ or an equimolar mix of individual agents, TMZ plus perillyl alcohol. The superior cytotoxic impact of NEO212 appeared to involve down-regulation of MGMT protein levels. In a mouse model implanted with TMZ-resistant, MGMT-positive AML cells, two 5-day cycles of 25 mg/kg NEO212 achieved an apparent cure, as mice survived >300 days without any signs of disease. In parallel toxicity studies with rats, a 5-day cycle of 200 mg/kg NEO212 was well tolerated by these animals, whereas animals that were given 200 mg/kg TMZ all died due to severe leukopenia. Together, our results show that NEO212 exerts pleiotropic effects on AML cells that include differentiation, proliferation arrest, and eventual cell death. In vivo, NEO212 was well tolerated even at dosages that far exceed the therapeutic need, indicating a large therapeutic window. These results present NEO212 as an agent that should be considered for development as a therapeutic agent for AML.
PubMed: 36551551
DOI: 10.3390/cancers14246065 -
BMC Biology Nov 2022The SARS-CoV-2/COVID-19 pandemic has inflicted medical and socioeconomic havoc, and despite the current availability of vaccines and broad implementation of vaccination...
BACKGROUND
The SARS-CoV-2/COVID-19 pandemic has inflicted medical and socioeconomic havoc, and despite the current availability of vaccines and broad implementation of vaccination programs, more easily accessible and cost-effective acute treatment options preventing morbidity and mortality are urgently needed. Herbal teas have historically and recurrently been applied as self-medication for prophylaxis, therapy, and symptom alleviation in diverse diseases, including those caused by respiratory viruses, and have provided sources of natural products as basis for the development of therapeutic agents. To identify affordable, ubiquitously available, and effective treatments, we tested herbs consumed worldwide as herbal teas regarding their antiviral activity against SARS-CoV-2.
RESULTS
Aqueous infusions prepared by boiling leaves of the Lamiaceae perilla and sage elicit potent and sustained antiviral activity against SARS-CoV-2 when applied after infection as well as prior to infection of cells. The herbal infusions exerted in vitro antiviral effects comparable to interferon-β and remdesivir but outperformed convalescent sera and interferon-α2 upon short-term treatment early after infection. Based on protein fractionation analyses, we identified caffeic acid, perilla aldehyde, and perillyl alcohol as antiviral compounds. Global mass spectrometry (MS) analyses performed comparatively in two different cell culture infection models revealed changes of the proteome upon treatment with herbal infusions and provided insights into the mode of action. As inferred by the MS data, induction of heme oxygenase 1 (HMOX-1) was confirmed as effector mechanism by the antiviral activity of the HMOX-1-inducing compounds sulforaphane and fraxetin.
CONCLUSIONS
In conclusion, herbal teas based on perilla and sage exhibit antiviral activity against SARS-CoV-2 including variants of concern such as Alpha, Beta, Delta, and Omicron, and we identified HMOX-1 as potential therapeutic target. Given that perilla and sage have been suggested as treatment options for various diseases, our dataset may constitute a valuable resource also for future research beyond virology.
Topics: Humans; SARS-CoV-2; Antiviral Agents; Teas, Herbal; Pandemics; COVID-19 Serotherapy; COVID-19 Drug Treatment
PubMed: 36447206
DOI: 10.1186/s12915-022-01468-z -
Current Pharmaceutical Design Nov 2022Naturally occurring bioactive compounds have a plethora of biological effects.
BACKGROUND
Naturally occurring bioactive compounds have a plethora of biological effects.
OBJECTIVE
In this study, we examined a pharmacological screening of natural products on the human umbilical artery (HUA).
METHODS
HUA preparations were used to follow contractions by KCl (60 mM) and tested at different concentrations (1-5000 μg/mL and μM) of the Lippia alba (EOLa) and Lippia origanoides (EOLo) essential oils, terpenes (citral, limonene perilic alcohol) and phenylpropanoids (eugenol, methyl eugenol). Discussion/Results: The reduction corresponded to approximately 100%, except for limonene (80±1.2 %). When evaluating the concentration of the natural product that promotes 50 % relaxation of the HUA contracted by KCL, EC50 values were: 424.3 μg/mL (EOLa); 468.7±6.7 μg/mL (EOLo); 264.2 ± 8.2 μM (citral); 677.8±5.4 μM (limonene); 186.3±6.4 μM (peryl alcohol); 986.4±7.9 μM (eugenol); and 279.1±4.4 μM (methyl-eugenol). Perillyl alcohol had a lower EC50 (consequently it has a higher pharmacological potency).
CONCLUSION
The plant extracts have a promising vasorelaxing effect in HUAs, paving the way for future investigations: as applications in diseases related to these vessels, such as preeclampsia.
PubMed: 36424792
DOI: 10.2174/1381612829666221124101321 -
Archives of Biochemistry and Biophysics Nov 2022Rhodococcus globerulus (R. globerulus) isolated from soil beneath Eucalyptus sp. was found to live on the monoterpenes 1,8-cineole, p-cymene and (R)- and (S)-limonene as...
Rhodococcus globerulus (R. globerulus) isolated from soil beneath Eucalyptus sp. was found to live on the monoterpenes 1,8-cineole, p-cymene and (R)- and (S)-limonene as sole sources of carbon and energy. Previous metabolic studies revealed that R. globerulus is capable of living on 1,8-cineole, the main monoterpene component of eucalyptus essential oil through the activity of cytochrome P450 (CYP176A1) [1]. Genomic sequencing of R. globerulus revealed a novel putative cytochrome P450 (CYP108N12) that shares 48% sequence identity with CYP108A1 (P450) from Pseudomonas sp., an α-terpineol hydroxylase. Given the sequence similarity between CYP108N12 and P450, it was hypothesised that CYP108N12 may be responsible for initiating the biodegradation of a monoterpene structurally similar to α-terpineol such as (R)-limonene, (S)-limonene or p-cymene. Encoded within the operon containing CYP108N12 were two putative bacterial P450 redox partners and putative alcohol and aldehyde dehydrogenases, suggesting a complete catalytic system for activating these monoterpenes. Binding studies revealed that p-cymene and (R)- and (S)-limonene all bound tightly to CYP108N12 but α-terpineol did not. A catalytically active system was reconstituted using the non-native redox partner putidaredoxin and putidaredoxin reductase that act with CYP101A1 (P450) from Pseudomonas. This reconstituted system catalysed the hydroxylation of p-cymene to 4-isopropylbenzyl alcohol, and (R)- and (S)-limonene to (R)- and (S)-perillyl alcohol, respectively. R. globerulus was successfully grown on solely p-cymene, (R)-limonene or (S)-limonene. CYP108N12 was detected when R. globerulus was grown on p-cymene, but not either limonene enantiomer. The native function of CYP108N12 is therefore proposed to be initiation of p-cymene biodegradation by methyl oxidation and is a potentially attractive biocatalyst capable of specific benzylic and allylic hydroxylation.
Topics: Limonene; Eucalyptol; Monoterpenes; Cytochrome P-450 Enzyme System; Pseudomonas; Carbon; Soil; Oils, Volatile; Aldehydes; Terpenes
PubMed: 36155781
DOI: 10.1016/j.abb.2022.109410