Characterization of Caffeoylquinic Acids from Lepisorus thunbergianus and Their Melanogenesis Inhibitory Activity

Mexican calea (Calea zacatechichi Schltdl.) interferes with cholinergic and dopaminergic pathways and causes neuroglial toxicity

ETHNOPHARMACOLOGICAL RELEVANCE

The use of "Mexican calea" (Calea zacatechichi Schltdl.) in ritualistic ceremonies, due to its dream-inducing effects, was until recently limited to indigenous communities in Mexico. However, the plant has recently gained popularity in Western societies being commonly used in recreational settings. Despite the traditional and recreational uses, mechanisms underlying its reported oneirogenic effects remain unknown, with no data available on its neurotoxic profile.

AIM OF THE STUDY

The scarcity of toxicological data and the unknown role of major neurotransmitter systems in the dream-inducing properties of the plant prompted us to investigate which neurotransmitters might be affected upon its consumption, as well as the potential cytotoxic effects on neurons and microglial cells. Furthermore, we aimed to explore a relationship between the recorded effects and specific constituents.

MATERIALS AND METHODS

Effects on cholinergic and monoaminergic pathways were investigated using enzymatic assays, with the latter also being conducted in neuronal SH-SY5Y cells along with the impact on glutamate-induced excitotoxicity. Investigation of the neurotoxic profile was approached in neuronal SH-SY5Y and microglial BV-2 cells, evaluating effects on metabolic performance and membrane integrity using MTT and LDH leakage assays, respectively. Potential interference with oxidative stress was monitored by assessing free radical's levels, as well as 5-lipoxygenase mediated lipid peroxidation. Phenolic constituents were identified through HPLC-DAD-ESI(Ion Trap)MSn analysis.

RESULTS

Based on the significant inhibition upon acetylcholinesterase (p < 0.05) and tyrosinase (IC50 = 60.87 ± 7.3 μg/mL; p < 0.05), the aqueous extract obtained from the aerial parts of C. zacatechichi interferes with the cholinergic and dopaminergic systems, but has no impact against monoamine oxidase A. Additionally, a notable cytotoxic effect was observed in SH-SY5Y and BV-2 cells at concentrations as low as 125 and 500 μg/mL (p < 0.05), respectively, LDH leakage suggesting apoptosis may occur at these concentrations, with necroptosis observed at higher ones. Despite the neurocytotoxic profile, these effects appear to be independent of radical stress, as the C. zacatechichi extract scavenged nitric oxide and superoxide radicals at concentrations as low as 62.5 μg/mL, significantly inhibiting also 5-lipoxygenase (IC50 = 72.60 ± 7.3 μg/mL; p < 0.05). Qualitative and quantitative analysis using HPLC-DAD-ESI(Ion Trap)MSn enabled the identification of 28 constituents, with 24 of them being previously unreported in this species. These include a series of dicaffeoylquinic, caffeoylpentoside, and feruloylquinic acids, along with 8 flavonols not previously known to occur in the species, mainly 3-O-monoglycosylated derivatives of quercetin, kaempferol, and isorhamnetin.

CONCLUSIONS

Our findings regarding the neuroglial toxicity elicited by C. zacatechichi emphasize the necessity for a thorough elucidation of the plant's toxicity profile. Additionally, evidence is provided that the aerial parts of the plant inhibit both acetylcholinesterase and tyrosinase, potentially linking its psychopharmacological effects to the cholinergic and dopaminergic systems, with an apparent contribution from specific phenolic constituents previously unknown to occur in the species. Collectively, our results lay the groundwork for a regulatory framework on the consumption of C. zacatechichi in recreational settings and contribute to elucidating previous contradictory findings regarding the mechanisms underlying the dream-inducing effects of the plant.

Unlocking the Bioactive Potential and Exploring Novel Applications for Portuguese Endemic Santolina impressa

The infusion of Santolina impressa, an endemic Portuguese plant, is traditionally used to treat various infections and disorders. This study aimed to assess its chemical profile by HPLC-DAD-ESI-MSn and validate its anti-inflammatory potential. In addition, the antioxidant capacity and effects on wound healing, lipogenesis, melanogenesis, and cellular senescence, all processes in which a dysregulated inflammatory response plays a pivotal role, were unveiled. The anti-inflammatory potential was assessed in lipopolysaccharide (LPS)-stimulated macrophages, cell migration was determined using a scratch wound assay, lipogenesis was assessed on T0901317-stimulated keratinocytes and melanogenesis on 3-isobutyl-1-methylxanthine (IBMX)-activated melanocytes. Etoposide was used to induce senescence in fibroblasts. Our results point out a chemical composition predominantly characterized by dicaffeoylquinic acids and low amounts of flavonols. Regarding the infusion's bioactive potential, an anti-inflammatory effect was evident through a decrease in nitric oxide production and inducible nitric oxide synthase and pro-interleukin-1β protein levels. Moreover, a decrease in fibroblast migration was observed, as well as an inhibition in both intracellular lipid accumulation and melanogenesis. Furthermore, the infusion decreased senescence-associated β-galactosidase activity, γH2AX nuclear accumulation and both p53 and p21 protein levels. Overall, this study confirms the traditional uses of S. impressa and ascribes additional properties of interest in the pharmaceutical and dermocosmetics industries.

Identification of Peucedanum japonicum Thunb. extract components and their protective effects against dexamethasone-induced muscle atrophy

BACKGROUND

Peucedanum japonicum Thunb. (PJ) is a vegetable widely consumed in East Asia and is known to have anticancer and anti-inflammatory effects. However, the effect of PJ on muscle atrophy remains elusive.

PURPOSE

This study aimed to investigate the effect of PJ and its active compound on dexamethasone (DEX)-induced muscle atrophy.

METHODS

We performed qualitative and quantitative analysis of PJ using ultra-performance liquid chromatography-mass spectrometry tandem mass spectrometry (UPLC-MS/MS) and high-performance liquid chromatography (HPLC), respectively. The efficacy of PJ and its main compound 4-caffeoylquinic acid (CQA) on muscle atrophy was evaluated in DEX-induced myotube atrophy and DEX-induced muscle atrophy in mouse myoblasts (C2C12) and C57BL/6 mice, in vitro and in vivo, respectively.

RESULTS

The UPLC-MS/MS and HPLC data showed that the concentration of 4-CQA in PJ was 18.845 mg/g. PJ and 4-CQA treatments significantly inhibited DEX-induced myotube atrophy by decreasing protein synthesis and glucocorticoid translocation to the nucleus in C2C12 myotubes. In addition, PJ enhanced myogenesis by upregulating myogenin and myogenic differentiation 1 in C2C12 cells. PJ supplementation effectively increased muscle function and mass, downregulated atrogenes, and decreased proteasome activity in C57BL/6 mice. Additionally, PJ effectively decreased the nuclear translocation of forkhead transcription factor 3 alpha by inhibiting glucocorticoid receptor.

CONCLUSION

Overall, PJ and its active compound 4-CQA alleviated skeletal muscle atrophy by inhibiting protein degradation. Hence, our findings present PJ as a potential novel pharmaceutical candidate for the treatment of muscle atrophy.

Acyl-quinic acids from the root bark of Acanthopanax gracilistylus and their inhibitory effects on neutrophil elastase and cyclooxygenase-2 in vitro

Eleven new acyl-quinic acids (AQAs) 1a-9, and 18 known AQAs 10-27 were isolated from the root bark of Acanthopanax gracilistylus W. W. Smith (Acanthopanacis Cortex). The planar structures of 1a-9 were determined based on their HR-ESIMS, IR, and NMR data. The absolute configurations of 1a-6 were identified by comparing the experimental and the calculated electronic circular dichroism (ECD) spectra. This is the first report of the isolation of AQAs from Acanthopanacis Cortex. Notably, 1a-6 were determined as unusual oxyneolignan-(-)-quinic acids heterodimers, representing a new class of natural products. The inhibitory activities of 1a-27 on neutrophil elastase (NE) and cyclooxygenase-2 (COX-2) were studied in vitro, and the results indicated they possessed significant inhibitory activities on COX-2. Among them, the IC50 values of 1a-9 were 0.63±0.014, 0.75±0.028, 0.15±0.023, 0.63±0.016, 0.30±0.013, 35.63±4.600, 8.70±1.241, 16.51±0.480, 0.69±0.049, 0.39±0.017, and 0.26±0.080 μM, respectively. This study represents the inaugural disclosure of the anti-COX-2 constituents found in Acanthopanacis Cortex, thereby furnishing valuable insights into the exploration of novel COX-2 inhibitors derived from natural reservoirs.

Phytochemical Profiling, Antioxidant and Tyrosinase Regulatory Activities of Extracts from Herb, Leaf and In Vitro Culture of Achillea millefolium (Yarrow)

Achillea millefolium L. is one of the most known medicinal plants with a broad spectrum of applications in the treatment of inflammation, pain, microbial infections and gastrointestinal disorders. In recent years, the extracts from A. millefolium have also been applied in cosmetics with cleansing, moisturizing, shooting, conditioning and skin-lightening properties. The growing demand for naturally derived active substances, worsening environmental pollution and excessive use of natural resources are causing increased interest in the development of alternative methods for the production of plant-based ingredients. In vitro plant cultures are an eco-friendly tool for continuous production of desired plant metabolites, with increasing applicability in cosmetics and dietary supplements. The purpose of the study was to compare phytochemical composition and antioxidant and tyrosinase inhibitory properties of aqueous and hydroethanolic extracts from A. millefolium obtained from field conditions (AmL and AmH extracts) and in vitro cultures (AmIV extracts). In vitro microshoot cultures of A. millefolium were obtained directly from seeds and harvested following 3 weeks of culture. Extracts prepared in water, 50% ethanol and 96% ethanol were compared for the total polyphenolic content, phytochemical content using the ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-hr-qTOF/MS), antioxidant activity by DPPH scavenging assay and the influence on the activity of mushroom and murine tyrosinases. The phytochemical content of AmIV extracts was significantly different from AmL and AmH extracts. Most of the polyphenolic compounds identified in AmL and AmH extracts were present in AmIV extracts only in trace amounts and the major constituents presented in AmIV extracts were fatty acids. The total content of polyphenols in AmIV exceeded 0.25 mg GAE/g of dried extract, whereas AmL and AmH extracts contained from 0.46 ± 0.01 to 2.63 ± 0.11 mg GAE/g of dried extract, depending on the solvent used. The low content of polyphenols was most likely responsible for the low antioxidant activity of AmIV extracts (IC₅₀ values in DPPH scavenging assay >400 µg/mL) and the lack of tyrosinase inhibitory properties. AmIV extracts increased the activity of mushroom tyrosinase and tyrosinase present in B16F10 murine melanoma cells, whereas AmL and AmH extracts showed significant inhibitory potential. The presented data indicated that microshoot cultures of A. millefolium require further experimental research before they can be implemented as a valuable raw material for the cosmetics industry.

A Medicinal Halophyte Ipomoea pes-caprae (Linn.) R. Br.: A Review of Its Botany, Traditional Uses, Phytochemistry, and Bioactivity

Ipomoea pes-caprae (Linn.) R. Br. (Convolvulaceae) is a halophytic plant that favorably grows in tropical and subtropical countries in Asia, America, Africa, and Australia. Even though this plant is considered a pan-tropical plant, I. pes-caprae has been found to occur in inland habitats and coasts of wider areas, such as Spain, Anguilla, South Africa, and Marshall Island, either through a purposeful introduction, accidentally by dispersal, or by spreading due to climate change. The plant parts are used in traditional medicine for treating a wide range of diseases, such as inflammation, gastrointestinal disorders, pain, and hypertension. Previous phytochemical analyses of the plant have revealed pharmacologically active components, such as alkaloids, glycosides, steroids, terpenoids, and flavonoids. These phytoconstituents are responsible for the wide range of biological activities possessed by I. pes-caprae plant parts and extracts. This review arranges the previous reports on the botany, distribution, traditional uses, chemical constituents, and biological activities of I. pes-caprae to facilitate further studies that would lead to the discovery of novel bioactive natural products from this halophyte.

Valorization of Kiwiberry Leaves Recovered by Ultrasound-Assisted Extraction for Skin Application: A Response Surface Methodology Approach

This study aims to evaluate the optimal ultrasound-assisted extraction (UAE) conditions of antioxidants polyphenols from Actinidia arguta (Siebold & Zucc.) Planch. Ex Miq. (kiwiberry) leaves using a response surface methodology (RSM). The effects of solid:liquid ratio (2.5–10.0% w/v), time (20–60 min), and intensity (30–70 W/m²) on the total phenolic content (TPC) and antioxidant/antiradical activities were investigated. The optimal UAE conditions were achieved using a solid:liquid ratio of 10% (w/v) and an ultrasonic intensity of 30 W/m² for 31.11 min. The results demonstrated that the optimal extract showed a high TPC (97.50 mg of gallic acid equivalents (GAE)/g dw) and antioxidant/antiradical activity (IC₅₀ = 249.46 µg/mL for ABTS assay; IC₅₀ = 547.34 µg/mL for DPPH assay; 1440.13 µmol of ferrous sulfate equivalents (FSE)/g dw for ferric reducing antioxidant power (FRAP)) as well as a good capacity to scavenge superoxide and hypochlorous acid (respectively, IC₅₀ = 220.13 μg/mL and IC₅₀ =10.26 μg/mL), which may be related with the 28 phenolic compounds quantified. The in vitro cell assay demonstrated that the optimal extract did not decrease the keratinocytes’ (HaCaT) viability, while the fibroblasts’ (HFF-1) viability was greater than 70.63% (1000 µg/mL). This study emphasizes the great potential of kiwiberry leaves extracted by UAE for skin application.

A Comparative Study of Chemical Profiling and Biological Effects of Doronicum orientale Extracts

In this study, phytochemical and pharmacological screening of the aerial part and roots extracts from Doronicum orientale Hoffm. (Asteraceae) was carried out. Plant extracts were obtained using solvents of different polarity (hexane, ethyl acetate, ethanol, ethanol/water, water) for selection the most optimal solvent for the extraction of active compounds. For instance, the extracts yielded total phenolic and flavonoid contents in the range of 12.13-45.67 mg GAE/g and 0.75-12.44 mg QE/g, respectively, while the total antioxidant capacity of the extracts determined by the phosphomolybdenum assay ranged from 0.88-2.53 mmol TE/g. HPLC/MS/MS analysis revealed 5-caffeoylquinic acid (2.52-337.05 μg/g) and 3,5-dicaffeoylquinic acid (3.12-299.36 μg/g) to be the major components present in the investigated extracts. Antioxidant activity in terms of radical scavenging ability of the extracts ranged from 0.82-45.56 mg TE/g in DPPH assay and from 5.07-104.58 mg TE/g in ABTS assay. The tested extracts were found to inhibit acetylcholinesterase (aerial part: 0.50-2.33 mg GALAE/g; roots: 0.40-2.43 mg GALAE/g), while with the exception of the water extracts, the other extracts showed butyrylcholinesterase inhibition (aerial part: 2.46-5.02 mg GALAE/g; root: 2.93-4.17 mg GALAE/g). Overall, this study presented an interesting scope of this species in phytomedicine with preliminary data demonstrating some of the tested extracts to possess high bioactive contents, antioxidant potential and enzyme inhibitory activity. Thus, additional investigations are necessary to confirm their safety in herbal drug applications.

Inhibitory Effect of Chlorogenic Acid Analogues Comprising Pyridine and Pyrimidine on α-MSH-Stimulated Melanogenesis and Stability of Acyl Analogues in Methanol

In continuation of studies for α-MSH stimulated melanogenesis inhibitors, we have evaluated the design, synthesis, and activity of a new series of chlorogenic acid (CGA) analogues comprising pyridine, pyrimidine, and diacyl derivatives. Among nineteen synthesized compounds, most of them (fifteen) exhibited better inhibitions of melanin formation in B16 melanoma cells. The results illustrated that a pyridine analogue 6f and a diacyl derivative 13a of CGA showed superior inhibition profiles (IC50: 2.5 ± 0.7 μM and 1.1 ± 0.1 μM, respectively) of α-MSH activities than positive controls, kojic acid and arbutin (IC50: 54 ± 1.5 μM and 380 ± 9.5 μM, respectively). The SAR studies showed that both -CF3 and -Cl groups exhibited better inhibition at the meta position on benzylamine than their ortho and para positions. In addition, the stability of diacyl analogues of CGA in methanol monitored by HPLC for 28 days indicated the steric bulkiness of acyl substituents as a key factor in their stability.

Caffeoylquinic acids: chemistry, biosynthesis, occurrence, analytical challenges, and bioactivity

Caffeoylquinic acids (CQAs) are specialized plant metabolites we encounter in our daily life. Humans consume CQAs in mg-to-gram quantities through dietary consumption of plant products. CQAs are considered beneficial for human health, mainly due to their anti-inflammatory and antioxidant properties. Recently, new biosynthetic pathways via a peroxidase-type p-coumaric acid 3-hydroxylase enzyme were discovered. More recently, a new GDSL lipase-like enzyme able to transform monoCQAs into diCQA was identified in Ipomoea batatas. CQAs were recently linked to memory improvement; they seem to be strong indirect antioxidants via Nrf2 activation. However, there is a prevalent confusion in the designation and nomenclature of different CQA isomers. Such inconsistencies are critical and complicate bioactivity assessment since different isomers differ in bioactivity and potency. A detailed explanation regarding the origin of such confusion is provided, and a recommendation to unify nomenclature is suggested. Furthermore, for studies on CQA bioactivity, plant-based laboratory animal diets contain CQAs, which makes it difficult to include proper control groups for comparison. Therefore, a synthetic diet free of CQAs is advised to avoid interferences since some CQAs may produce bioactivity even at nanomolar levels. Biotransformation of CQAs by gut microbiota, the discovery of new enzymatic biosynthetic and metabolic pathways, dietary assessment, and assessment of biological properties with potential for drug development are areas of active, ongoing research. This review is focused on the chemistry, biosynthesis, occurrence, analytical challenges, and bioactivity recently reported for mono-, di-, tri-, and tetraCQAs.

Antioxidant and Mitochondria-Targeted Activity of Caffeoylquinic-Acid-Rich Fractions of Wormwood (Artemisia absinthium L.) and Silver Wormwood (Artemisia ludoviciana Nutt.)

Caffeoylquinic acids are some of the chemophenetically significant specialized metabolites found in plants of the family Asteraceae Dumort., possessing a broad spectrum of biological activities. As they might be potential mitochondria-targeted antioxidants, effective preparation methods—including extraction, isolation, and purification of caffeoylquinic acids from plant sources—are in great demand. The aim of this study was to fractionate the caffeoylquinic acids from cultivated wormwood (Artemisia absinthium L.) and silver wormwood (Artemisia ludoviciana Nutt.) herb acetone extracts and evaluate their phytochemical profiles, antioxidant activity (radical scavenging and reducing activities), effects on kidney mitochondrial functions, and cytochrome-c-reducing properties. The main findings of our study are as follows: (1) Aqueous fractions purified from wormwood and silver wormwood herb acetone extracts are rich in monocaffeoylquinic acids (chlorogenic acid, neochlorogenic acid, 4-O-caffeoylquinic acid), while methanolic fractions purified from wormwood and silver wormwood herb acetone extracts are rich in dicaffeoylquinic acids (4,5-dicaffeoylquinic acid, 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid). Aqueous fractions purified from wormwood and silver wormwood herb acetone extracts were solely composed of monocaffeoylquinic acids. Methanolic fractions purified from wormwood and silver wormwood herb acetone extracts contained only dicaffeoylquinic acids. (2) Fractions purified from silver wormwood herb acetone extracts stood out as having the greatest content of caffeoylquinic acids. (3) The greatest radical scavenging activity was determined in the dicaffeoylquinic-acid-rich fraction purified from silver wormwood herb acetone extract; the greatest reducing activity was determined in the dicaffeoylquinic-acid-rich fraction purified from wormwood herb acetone extract. (4) The effect of both fractions on mitochondrial functions was dose-dependent; lower concentrations of caffeoylquinic-acid-rich fractions had no effect on mitochondrial functions, whereas higher concentrations of caffeoylquinic-acid-rich fractions reduced the state 3 respiration rate (with the complex-I-dependent substrate glutamate/malate). (5) Both monocaffeoylquinic- and dicaffeoylquinic-acid-rich fractions possessed cytochrome-c-reducing properties; the greatest cytochrome c reduction properties were determined in the dicaffeoylquinic-acid-rich fraction purified from wormwood herb acetone extract. In summary, these findings show that caffeoylquinic acids might be beneficial as promising antioxidant and cytochrome-c-reducing agents for the modulation of mitochondria and treatment of various mitochondrial-pathway-associated pathologies.

Selecting and Characterizing Tyrosinase Inhibitors from Atractylodis macrocephalae Rhizoma Based on Spectrum-Activity Relationship and Molecular Docking

Atractylodis macrocephalae Rhizoma (AMR) is a famous classical Chinese traditional medicine (CTM), which has been used as a tonic for many diseases for thousands of years. In ancient China, it was used as a supplementary food for beauty in the palace. In preliminary studies, the function of whitening skin and the significant inhibiting effect on tyrosinase (TYR) which is the reactive enzyme in the composition of melanin of AMR were discovered, and the relevant research was rarely reported. In this study, high-performance liquid chromatography (HPLC) along with partial least squares regression analysis (PLS) was applied to survey the coherence between the chemical constituents and the inhibiting activity of 11 batches of AMR on TYR activity. The results of PLS showed that the chromatographic peaks 11 (atractylenolide III) and 15 could be important effective ingredients of the inhibition TYR activity as ascertained by spectrum-activity relationships. Furthermore, TYR inhibitory activity of atractylenolide III was validated by in vitro test by β-arbutin served as a positive control drug. The results of the in vitro test and the molecular docking showed that atractylenolide III has high TYR inhibitory activity and could link to the residues in TYR catalytic pocket. Therefore, bioassay, molecular docking, and spectrum-activity relationships are appropriate for linking the quality of samples with pharmaceutical-related active ingredients. And our studying would lay a theoretical foundation for applying the water extracts of AMR in whitening cosmetics.