Cytotoxic Acylphenols from Myristica maingayi

Therapeutic, and pharmacological prospects of nutmeg seed: A comprehensive review for novel drug potential insights

Background and objectives

For centuries, plant seed extracts have been widely used and valued for their benefits. They have been used in food, perfumes, aromatherapy, and traditional medicine. These natural products are renowned for their therapeutic properties and are commonly used in medicinal treatments. Their significant pharmacological profiles provide an excellent hallmark for the prevention or treatment of various diseases. In this study, we comprehensively evaluated the biological and pharmacological properties of nutmeg seeds and explored their efficacy in treating various illnesses.

Method

Published articles in databases including Google Scholar, PubMed, Elsevier, Scopus, ScienceDirect, and Wiley, were analyzed using keywords related to nutmeg seed. The searched keywords were chemical compounds, antioxidants, anti-inflammatory, antibacterial, antifungal, antiviral, antidiabetic, anticancer properties, and their protective mechanisms in cardiovascular and Alzheimer's diseases.

Results & discussion

Nutmeg seeds have been reported to have potent antimicrobial properties against a wide range of various bacteria and fungi, thus showing potential for combating microbial infections and promoting overall health. Furthermore, nutmeg extract effectively reduces oxidative stress and inflammation by improving the body's natural antioxidant defense mechanism. Nutmeg affected lipid peroxidation, reduced lipid oxidation, reduced low-density lipoprotein (LDL), and increased phospholipid and cholesterol excretion. In addition, nutmeg extract improves the modulation of cardiac metabolism, accelerates cardiac conductivity and ventricular contractility, and prevents cell apoptosis. This study elucidated the psychotropic, narcotic, antidepressant, and anxiogenic effects of nutmeg seeds and their potential as a pharmaceutical medicine. Notably, despite its sedative and toxic properties, nutmeg ingestion alone did not cause death or life-threatening effects within the dosage range of 20-80 g powder. However, chemical analysis of nutmeg extracts identified over 50 compounds, including flavonoids, alkaloids, and polyphenolic compounds, which exhibit antioxidant properties and can be used as phytomedicines. Moreover, the exceptional pharmacokinetics and bioavailability of nutmeg have been found different for different administration routes, yet, more clinical trials are still needed.

Conclusion

Understanding the chemical composition and pharmacological properties of nutmeg holds promise for novel drug discovery and therapeutic advancements. Nutmeg seed offers therapeutic and novel drug prospects that can revolutionize medicine. By delving into their pharmacological properties, we can uncover the vast potential possibilities of this natural wonder.

Acylphenols and Dimeric Acylphenols from the Genus Myristica: A Review of Their Phytochemistry and Pharmacology

The genus Myristica is a medicinally important genus belonging to the Myristicaceae. Traditional medicinal systems in Asia have employed plants from the genus Myristica to treat a variety of ailments. Acylphenols and dimeric acylphenols are a rare group of secondary metabolites, which, to date, have only been identified in the Myristicaceae, in particular, in the genus Myristica. The aim of the review would be to provide scientific evidence that the medicinal properties of the genus Myristica could be attributed to the acylphenols and dimeric acylphenols present in the various parts of its plants and highlight the potential in the development of the acylphenols and dimeric acylphenols as pharmaceutical products. SciFinder-n, Web of Science, Scopus, ScienceDirect, and PubMed were used to conduct the literature search between 2013-2022 on the phytochemistry and the pharmacology of acylphenols and dimeric acylphenols from the genus Myristica. The review discusses the distribution of the 25 acylphenols and dimeric acylphenols within the genus Myristica, their extraction, isolation, and characterization from the respective Myristica species, the structural similarities and differences within each group and between the different groups of the acylphenols and dimeric acylphenols, and their in vitro pharmacological activities.

Anti-Proliferative Acyl Phenols and Arylnonanoids from the Fruit Rind of Myristica malabarica Lam

Phytochemical investigation of the methanol extract of the fruit rind of Myristica malabarica led to the isolation of eight known compounds that were identified as malabaricones A-D, promalabaricones B and C, 1-(2,6-dihydroxyphenyl)tetradecan-1-one, and ericanone by comparison with literature spectroscopic data. The structures of malabaricones A-D, promalabaricone B, and 1-(2,6-dihydroxyphenyl)tetradecan-1-one were confirmed by X-ray crystallography. In vitro assay of the isolated phenols indicated that they exhibited moderate anti-proliferative activity against the A2780 human ovarian cancer cell. Compounds (1, 3, 5, 6 and 7) had the most potent activities, whereas the anti-proliferative activities of compounds 2 and 4 were less potent.

Malabaricone C derived from nutmeg inhibits arachidonate 5-lipoxygenase activity and ameliorates psoriasis-like skin inflammation in mice

As pro-inflammatory lipid mediators, leukotrienes have pathophysiological activities in several inflammatory diseases, including psoriasis. In the biosynthesis of leukotrienes from arachidonic acid, 5-lipoxygenase catalyzes the first two steps. In the present study, we showed that nutmeg (Myristica fragrans) strongly inhibited the catalytic activity of 5-lipoxygenase. To characterize the bioactive component(s) of nutmeg, we performed 5-lipoxygenase inhibitory activity-guided fractionation of aqueous ethanol extract of nutmeg, resulting in the isolation of malabaricone C having antioxidant activity. Malabaricone C exhibited potent competitive inhibition of 5-lipoxygenase with an IC₅₀ value of 0.2 μM. In mice with imiquimod-induced psoriasis-like skin lesions, topical application of 2 mM malabaricone C significantly ameliorated hyperplasia and inflammatory cell infiltration, and suppressed the expression of the psoriasis-associated genes S100a9, Krt1, Il17a, and Il22. Lipid metabolome analysis of these psoriasis-like skin lesions showed that malabaricone C markedly decreased the level of leukotriene B₄ but did not significantly increase the other pro-inflammatory lipid mediators. These findings suggest that malabaricone C decreases LTB₄ by the 5-lipoxygenase inhibition and ameliorates the symptoms of psoriasis-like skin inflammation.

Promalabaricone B from Myristica fatua Houtt. seeds demonstrate antidiabetic potential by modulating glucose uptake via the upregulation of AMPK in L6 myotubes

Promalabaricone B (PMB), an acylphenol was isolated from dichloromethane-soluble extract of the seeds of Myrisitica fatua Houtt. PMB exhibited significant inhibitory activity on α-glucosidase enzyme. The molecular docking and dynamics studies of PMB with human maltase-glucoamylase were performed. PMB exhibited an enhanced glucose uptake in L6 myotubes with 46.3% in 2.5 µM. Encouraged with these results; we investigated the molecular mechanism of PMB through the upregulation of AMPK. The results revealed that PMB promoted the glucose uptake in myocytes by stimulating the translocation and expression of GLUT4. From this, it is clear that PMB can acts as a potential therapeutic option for diabetes treatment, and its hypoglycaemic effect may be mediated by AMPK upregulation and induction of GLUT4 translocation.

Total Syntheses of Malabaricones B and C via a Cross-Metathesis Strategy

The malabaricones A-D belong to the class of diarylnonanoids isolated from the Myristicaceae family of plants. Although malabaricone C displayed various interesting biological activities, its isolation remains tedious due to its close chemical similarity to malabaricones A, B, and D. Therefore, development of an efficient synthesis route has become essential to cater to the need of large amounts of malabaricone C for its pharmacological profiling. So far there is only one report of the synthesis of malabaricone C through a lengthy sequence of reactions. We have developed an efficient and short route for the syntheses of malabaricones B and C, which will also provide a convenient access to all other members of the malabaricone family. Synthesis of an important building block, ω-aryl heptyl bromide, employed in the synthesis was realized by adopting a cross-metathesis reaction as the key step.

Quorum Sensing Inhibitory Activity of Giganteone A from Myristica cinnamomea King against Escherichia coli Biosensors

Malabaricones A-C (1-3) and giganteone A (4) were isolated from the bark of Myristica cinnamomea King. Their structures were elucidated and characterized by means of NMR and MS spectral analyses. These isolates were evaluated for their anti-quorum sensing activity using quorum sensing biosensors, namely Escherichia coli [pSB401] and Escherichia coli [pSB1075], whereby the potential of giganteone A (4) as a suitable anti-quorum sensing agent was demonstrated.

A potent alpha-glucosidase inhibitor from Myristica cinnamomea King

A dimeric acylphenol and a potent α-glucosidase inhibitor, giganteone D (IC50 5.05μM), was isolated and characterized from the bark of Myristica cinnamomea King. The bark also yielded an acylphenol with an unprecedented skeleton for which the name cinnamomeone A (IC50 358.80μM) was proposed. Their structures were established by means of NMR and MS spectrometric analyses. The Lineweaver-Burk plot of giganteone D indicated that it was a mixed-type inhibitor. This is the first report on the α-glucosidase inhibiting potential of acylphenols.

Potent Acetylcholinesterase Inhibitory Compounds from Myristica fragrans

The anti-cholinesterase activity was evaluated of the ethyl acetate fraction of the methanol extract of Myristica fragrans Houtt (Myristicaceae) seeds and of compounds isolated from it by various chromatographic techniques. The chemical structures of the compounds were determined from spectroscopic analyses (NMR data). Thirteen compounds (1—13) were isolated and identified. Compound 8 {[(7S)-8′-(4′-hydroxy-3′-methoxyphenyl)-7-hydroxypropyl]benzene-2,4-diol} showed the most effective activity with an IC50 value of 35.1 μM, followed by compounds 2 [(8R,8′S)-7′-(3′,4′-methylenedioxyphenyl)-8,8′-dimethyl-7-(3,4-dihydroxyphenyl)-butane] and 11 (malabaricone C) with IC50 values of 42.1 and 44.0 μM, respectively. This is the first report of significant anticholinesterase properties of M. fragrans seeds. The findings demonstrate that M. fragrans could be used beneficially in the treatment of Alzheimer's disease.

A new acyclic diterpene acid and bioactive compounds from Knema glauca

Investigation of the chemical constituents of the fruits of Knema glauca (Myristicaceae) yielded a new acyclic diterpene acid, named glaucaic acid 4, together with four acylphenols, including 1-(2,6-dihydroxyphenyl) tetradecan-1-one 1, malabaricone A 6, dodecanoylphloroglucinol 7 and 1-(2,4,6-trihydroxyphenyl)-9-phenylnonan-1-one 8, two lignans sesamin 2 and asarinin 3, and a flavan, myristinin D 5. In addition, myristinin A 9 and (+/-)-7,4'-dihydroxy-3'-methoxyflavan 10 were isolated from its leaves and stems, respectively. When tested against small-cell lung cancer (NCI-H187), epidermoid carcinoma (KB) and breast cancer (BC) cell lines, compounds 1, 6-8 and 10 displayed weak to moderate cytotoxicity. The acylphenols 6-8 displayed antituberculosis activity against the microbe Mycobacterium tuberculosis with MIC values of 25, 50 and 100 microg/mL, respectively, and antiviral activity against herpes simplex virus type 1, with 7 as the most active compound (IC(50) = 3.05 microg/mL). Malabaricone A 6 was also active against the malarial parasite Plasmodium falciparum with an IC(50) value of 2.78 microg/mL.

Gas-phase reactivity of acylphenols in electrospray and matrix-assisted laser desorption ionization mass spectrometry

Acylphenols from Myristica crassa were identified based on liquid chromatography high-resolution mass spectrometry and liquid chromatography tandem mass spectrometry (MS/MS) experiments. Two types of compound were found in the extract of the plant: monomeric (malabaricone B and C) and dimeric compounds (C-C bonded biphenyl and C-C bonded phenyl-linear carbon chain). Evidence of formation of covalent dimeric ions during the electrospray ionization and matrix-assisted laser desorption ionization (MALDI) processes was established. [2M-3H](-) dimeric ions were detected on the mass spectra of each monomeric compound during high-performance liquid chromatography separation. The MS/MS spectra of those species were compared to the MS/MS spectra obtained for the dimeric compounds synthesized by the plant. Fragmentation pathways were studied for the two classes of dimer. The dimeric ions formed in the ion source were C-C bonded biphenyl compounds. Further evidence was obtained from MALDI experiments: increase in the extraction delay time leads to an increase of the dimeric ions relative abundance. Their formation is based on the high reactivity of phenols or phenolate ions which are easily oxidized yielding phenoxy radicals.