Anti-Inflammatory, Antinociceptive, and Antioxidant Properties of Anacardic Acid in Experimental Models

Effects of cardanol-based phospholipid analogs on Trichomonas vaginalis

Trichomonas vaginalis is a protist parasite of the urogenital tract, responsible for human trichomoniasis, an infection sexually transmitted that affects approximately 156 million people worldwide. This pathology is more evident in females and can cause miscarriages, premature births, and infertility. The disease can also lead to a greater predisposition to HIV infection and cervical and prostate cancer. Metronidazole (MTZ) is a drug that treats human trichomoniasis. The data from studies involving human subjects are limited regarding MTZ use during pregnancy. In addition to the toxicity of the treatment, some isolates have become resistant to MTZ. Therefore, searching for new compounds active for treating trichomoniasis becomes necessary. In the present study, we report results obtained using new phospholipid analogs. Two cardanol-based compounds designated LDT117 and LDT134 were active against T. vaginalis with an IC50 of 4.58 and 10.24 μM, respectively. These compounds were not toxic to epithelial cells in culture. Scanning electron microscopy observations revealed a rounding of the cells, a shortening of the flagella, and protrusions on the surface of drug-treated cells. Transmission electron microscopy of treated cells revealed alterations in the plasma membrane with formations of blebs, protrusions, depressions, and vacuoles with myelin figures and vacuolization in the cytoplasm after incubation. Furthermore, after treatments with the compounds LDT117 and LDT134, the parasites presented a positive reaction for TUNEL, indicating death by a mechanism like apoptosis. Given the results obtained, further in vivo studies using animal experimental models are necessary to validate that these compounds are effective for treating human trichomoniasis.

Ferulic acid via attenuation of oxidative stress and neuro-immune response utilizes antinociceptive effect in mouse model of formalin test

Introduction

Plenty evidences suggests that neuroinflammation and oxidative stress augmented the neural sensitivity specifying that neuro-immune response is involved in the pathophysiology of pain. Ferulic acid (FA), a natural antioxidant found in various fruits, has various pharmacological properties. The purpose of the current study was to assess the antinociceptive effect of FA in a mouse model of formalin test with focus on its anti-neuroinflammatory and antioxidative stress effects.

Methods

The injection of FA (40 mg/kg), piroxicam (2 mg/kg), and saline (0.9% NaCl) (1 ml/kg) was done intraperitoneally and after one hour, formalin injected into the plantar surface of the hind paw of mice. Then pain behavior was documented during 60 min. Then mice were euthanized and prefrontal cortex (PFC) samples were taken. Malondialdehyde (MDA) level, antioxidant capacity and expression of inflammatory genes, counting tumor necrosis factor (TNF-) and interleukine 1 (IL-1) evaluated in the PFC.

Results

exhibited that FA declined the pain behavior following injection of formalin. Besides, FA significantly diminished the MDA level and increased the antioxidant capacity in the PFC. We revealed that FA diminished the expression of TNF-α and IL-1β genes in the PFC.

Conclusion

We conclude that FA exerted antinociceptive effects in the formalin test in mice, at least partially, by reducing oxidative stress and neuroimmune response in the PFC.

Comparison of supercritical CO2 extraction and pressurized fluid extraction for isolation of alkaloids from Anacardium occidentale with the study of its anti-inflammatory activity

In recent years, there has been a growing interest in the therapeutic potential of natural compounds, particularly of plant origin, owing to their demonstrated anti-inflammatory properties. Among these, Anacardium occidentale, commonly known as cashew, has garnered significant attention due to its reputed health benefits. This study aim to establish a correlation between the bioactive compounds contained in the extracts of Anacardium occidentale and its anti-inflammatory activity. Dried Anacardium occidentale leaves powder was used as the extraction matrix. Extraction techniques are maceration, pressurized fluid extraction (PFE), and supercritical fluid extraction (SFE). The preliminary analysis of extracts was made by LC-MS/MS. The Response Surface Methodology (RSM), Principal Component Analysis (PCA), and heat maps were employed to model the influence of experimental conditions on extraction yield and peak area of specific compounds from the plant. To evaluate anti-inflammatory activity, RAW 264.7 cells were cultured, activated with LPS, and treated with varying concentrations of the plant extracts. Cell proliferation was assessed using the XTT assay. Indeed, Anacardium occidentale extracts contain anacardic acids, cardanols, and cardol, with distinct profiles yielded by SFE and ethanol-based methods. RSM shows that temperature and ethanol, as additives to CO2, significantly affect extraction efficiency in both PFE and SFE. Moreover, this composition with SFE demonstrate higher selectivity for specific group of compounds. The extracts exhibit anti-inflammatory properties without cytotoxicity in macrophages, reducing levels of pro-inflammatory proteins COX-2, COX-1, and TLR4 in activated cells. This suggests their potential as anti-inflammatory agents without adverse effects on cell viability or pro-inflammatory protein levels in non-activated cells. Overall, these findings underscore the promising therapeutic potential of Anacardium occidentale extracts in mitigating inflammation, while also providing crucial insights into optimizing the extraction process for targeted compound isolation. Thus, this makes a good prospect for the development of anti-inflammatory drugs from this plant.

Ethnomedicinal, Chemical, and Biological Aspects of Lannea Species-A Review

Lannea L. genus belongs to the Anacardiaceae botanical family and has long been used in traditional medicinal systems of many countries to manage several health conditions, but no studies have been conducted regarding its usefulness as a source of herbal medicine for human use. A literature review was conducted on scientific papers indexed on B-On, Pubmed, and Web of Science databases. Our results showed that medicinal plants from this botanical genus, mostly constituted by bark and leaf, are often used to approach a wide variety of disease symptoms, like fever, inflammatory states, pain, and gastrointestinal disorders. Phytochemical profiles of Lannea species revealed that phenolic acid derivatives including hydroquinones, phenolic acids, flavonoids, condensed tannins, and triterpenoids are the main classes of secondary metabolites present. Among the total of 165 identified compounds, 57 (34.5%) are flavonoids, mostly quercetin- and myricetin-derived flavonols and catechin and epicatechin flavan-3-ol derivatives also containing a galloyl group. In vitro and in vivo studies allowed the identification of 12 different biological activities, amongst which antimicrobial, antioxidant, anti-inflammatory, and cytotoxic activities were the most frequently cited and observed in in vitro essays. Our review contributes useful information for the scientifical validation of the use of Lannea species in traditional medicinal systems and shows that more research needs to be conducted to better understand the concrete utility of these as herbal medicines.

Green Extracts with Metal-based Nanoparticles for Treating Inflammatory Diseases: A Review

Globally, high death rates and poor quality of life are caused mainly by inflammatory diseases. Corticosteroids, which may have systemic side effects and would enhance the risk of infection, are the common forms of therapy. The field of nanomedicine has created composite nanoparticles that carry a pharmacological carrier and target ligands for distribution to sites of inflammation with less systemic toxicity. However, their relatively large size often causes systemic clearance. An interesting approach is metal-based nanoparticles that naturally reduce inflammation. They are made not only to be small enough to pass through biological barriers but also to allow label-free monitoring of their interactions with cells. The following literature review discusses the mechanistic analysis of the anti-inflammatory properties of several metal-based nanoparticles, including gold, silver, titanium dioxide, selenium, and zinc oxide. Current research focuses on the mechanisms by which nanoparticles infiltrate cells and the anti-inflammatory techniques using herbal extracts-based nanoparticles. Additionally, it provides a brief overview of the literature on many environmentally friendly sources employed in nanoparticle production and the mechanisms of action of various nanoparticles.

Anacardic acid improves neurological deficits in traumatic brain injury by anti-ferroptosis and anti-inflammation

BACKGROUND

Traumatic brain injury (TBI) is an important cause of disability and death. TBI leads to multiple forms of nerve cell death including ferroptosis due to iron-dependent lipid peroxidation. Anacardic acid (AA) is a natural component extracted from cashew nut shells, which has been reported to have neuroprotective effects in traumatic brain injury. We investigated whether AA has an anti-ferroptosis effect in TBI.

METHODS

We used the Feeney free-fall impact method to construct a TBI model to investigate the effect of AA on ferroptosis caused by TBI, in which Ferrostatin-1 (Fer-1), a ferroptosis inhibitor, served as a positive control group. We first identified the therapeutic effect of AA on TBI through modified neurological severity score (mNSS) and determined the appropriate concentration. Secondly, we investigated the effect of AA on the expression level of the key protein of ferroptosis by Western blotting and immunohistochemistry. Then the effect of AA on nerve tissue injury and nerve function improvement was verified. Finally, enzym-linked immunosorbent assay (ELISA) was used to verify that AA could reduce inflammation after TBI.

RESULTS

We found the intensely inhibitory effect of AA on ferroptosis, which is in parallel with the results obtained after Fer-1 treatment. In addition, AA and Fer-1 mitigated TBI-mediated tissue defects, destruction of the blood-brain barrier, and neurodegeneration. Novel object recognition (NOR), mNSS and water maze test showed that AA could significantly reduce the impairment of neural function and behavioral cognitive ability caused by TBI. Finally, we also demonstrated that AA has not only an anti-ferroptosis effect, but also an anti-inflammation effect.

CONCLUSIONS

AA can reduce the neurological impairment and behavioral cognitive impairment caused by TBI through the dual effect of anti-ferroptosis and anti-inflammation.

Valorizing Constituents of Cashew Nut Shell Liquid toward the Sustainable Development of New Drugs against Chagas Disease

Six new ether phospholipid analogues encompassing constituents from cashew nut shell liquid as the lipid portion were synthesized in an effort to valorize byproducts of the cashew industry toward the generation of potent compounds against Chagas disease. Anacardic acids, cardanols, and cardols were used as the lipid portions and choline as the polar headgroup. The compounds were evaluated for their in vitro antiparasitic activity against different developmental stages of Trypanosoma cruzi. Compounds 16 and 17 were found to be the most potent against T. cruzi epimastigotes, trypomastigotes, and intracellular amastigotes exhibiting selectivity indices against the latter 32-fold and 7-fold higher than current drug benznidazole, respectively. Hence, four out of six analogues can be considered as hit-compounds toward the sustainable development of new treatments for Chagas disease, based on inexpensive agro-waste material.

Uncovering heterogeneity of anacardic acids from pistachio shells: A novel approach for structural characterization

Anacardic acids (AnAs) are important secondary metabolites that occur primarily in plants of the Anacardiaceae family, such as pistachio (Pistacia vera L.). Some AnAs have been associated with health benefits, and the position of the CC double bonds is a crucial feature of these metabolites. Herein, we propose a new strategy based on RPLC separation and detection by ESI-MS/MS, preceded by an epoxidation reaction. The procedure was applied to the green extracts of lignified pistachio shells, and a mixture of AnAs bearing alkyl chains 13:0, 15:0, and 17:1 emerged as prevailing. As positional isomers of AnA 15:1 (Δ⁸ and Δ⁶) and AnAs 17:1 (Δ¹⁰ and Δ⁸) were identified for the first time, their discovery paves the way to the systematic study of their potential health-beneficial effects. The developed method was validated and applied to quantify AnAs in pistachio ethanolic extract, showing contents higher than 10 mg/ 100 g of biomass.

Nutrigenomics in Parkinson's disease: diversity of modulatory actions of polyphenols on epigenetic effects induced by toxins

Although the pathogenesis of Parkinson's Disease (PD) is not completely understood, there is a consensus that it can be caused by multifactorial mechanisms involving genetic susceptibility, epigenetic modifications induced by toxins and mitochondrial dysfunction. In the past 20 years, great efforts have been made in order to clarify molecular mechanisms that are risk factors for this disease, as well as to identify bioactive agents for prevention and slowing down of its progression. Nutraceutical products have received substantial interest due to their nutritional, safe and therapeutic effects on several chronic diseases. The aim of this review was to gather the main evidence of the epigenetic mechanisms involved in the neuroprotective effects of phenolic compounds currently under investigation for the treatment of toxin-induced PD. These studies confirm that the neuroprotective actions of polyphenols involve complex epigenetic modulations, demonstrating that the intake of these natural compounds can be a promising, low-cost, pharmacogenomic strategy against the development of PD.

Aniba canelilla (Kunth) Mez (Lauraceae) Essential Oil: Effects on Oxidative Stress and Vascular Permeability

The present study aimed to investigate the antioxidant activity of Aniba canelilla (kunth) Mez (Lauraceae) essential oil (AcEO), exploring its potential for prevention and/or treatment of oxidative stress and associated inflammatory process. With this aim, Wistar rats (n = 6/group) were pre-treated intraperitoneally with saline (0.9%) or AcEO (2 or 5 mg/kg) for 5 days. One hour after the last dose, inflammation and oxidative stress were induced by carrageenan (0.3 mg/kg; ip.) administration. Total antioxidant capacity, reduced glutathione (GSH) and lipid peroxidation levels, protein concentration, and leukocyte migration were evaluated in peritoneal fluid. Lipid peroxidation was also evaluated in plasma. Carrageenan strongly reduced the peritoneal antioxidant capacity and GSH concentration, increasing peritoneal and plasma lipid peroxidation. It also promoted increased plasma leakage and leukocyte migration. Treatment with AcEO (2 and 5 mg/kg), whose major constituent was 1-nitro-2-phenylethane (77.5%), increased the peritoneal antioxidant capacity and GSH concentrations, and reduced lipid peroxidation, both peritoneal and plasma, thus inhibiting the carrageenan-induced oxidative imbalance. AcEO also reduced the carrageenan-induced plasma leakage and leukocyte migration. These data demonstrate the AcEO antioxidant activity and its ability to modulate plasma leakage and leukocyte migration, confirming its potential for treating diseases associated with inflammation and oxidative stress.

Rhodojaponin III-Loaded Chitosan Derivatives-Modified Solid Lipid Nanoparticles for Multimodal Antinociceptive Effects in vivo

Background

Rhodojaponin III (RJ-III) is a bioactive diterpenoid, which is mainly found in Rhododendron molle G. Don (Ericaceae), a potent analgesia in traditional Chinese medicine with several years of clinical applications in the country. However, its clinical use is limited by its acute toxicity and poor pharmacokinetic profiles. To reduce such limitations, the current study incorporated RJ-III into the colloidal drug delivery system of hydroxypropyl trimethyl ammonium chloride chitosan (HACC)-modified solid lipid nanoparticles (SLNs) to improve its sustained release and antinociceptive effects in vivo for oral delivery.

Results

The optimized RJ-III@HACC-SLNs were close to spherical, approximately 134 nm in size, and with a positive zeta potential. In vitro experiments showed that RJ-III@HACC-SLNs were stable in the simulated gastric fluid and had a prolonged release in PBS (pH = 6.8). Pharmacokinetic results showed that after intragastric administration in mice, the relative bioavailability of RJ-III@HACC-SLNs was 87.9%. Further, it was evident that the peak time, half-time, and mean retention time of RJ-III@HACC-SLNs were improved than RJ-III after the administration. In addition, pharmacodynamic studies revealed that RJ-III@HACC-SLNs markedly reduced the acetic acid, hot, and formalin-induced nociceptive responses in mice (P < 0.001), and notably increased the analgesic time (P < 0.01). Moreover, RJ-III@HACC-SLNs not only showed good biocompatibility with Caco-2 cells in vitro but its LD₅₀ value was also increased by 1.8-fold as compared with that of RJ-III in vivo.

Conclusion

These results demonstrated that RJ-III@HACC-SLNs improved the pharmacokinetic characteristics of the RJ-III, thereby exhibiting toxicity-attenuating potential and antinociceptive enhancing properties. Consequently, HACC-SLNs loaded with RJ-III could become a promising oral formulation for pain management that deserves further investigation in the future.

Oleic acid-related anti-inflammatory effects in force-stressed PdL fibroblasts are mediated by H3 lysine acetylation associated with altered IL10 expression

The initiation of a spatially and temporally limited inflammation is essential for tissue and bone remodelling by the periodontal ligament (PdL) located between teeth and alveolar bone. Nutritional components may cause alterations in the inflammatory response of PdL fibroblasts to mechanical stress such as those occurring during orthodontic tooth movement (OTM). Recently, we reported an attenuated pro-inflammatory response of human PdL fibroblasts (HPdLFs) to compressive forces when stimulated with oleic acid (OA), a monounsaturated fatty acid particularly prominent in the Mediterranean diet. Fatty acids could serve as alternative source of acetyl-CoA, thereby affecting epigenetic histone marks, such as histone 3 lysine acetylation (H3Kac) in a lipid metabolism-dependent manner. In this study, we aimed to investigate the extent to which OA exerts its anti-inflammatory effect in compressed HPdLFs via changes in H3Kac. Six-hour compressed HPdLFs showed increased H3Kac when cultured with OA. Inhibition of histone deacetylases resulted in a comparable IL10-increase as observed in compressed OA-cultures. In contrast, inhibition of histone acetyltransferases, particularly p300/CBP, in compressed HPdLFs exposed to OA normalized the inflammatory response to control levels. OA-dependent increased association of H3Kac to IL10 promoter regions in compressed HPdLFs further strengthened the assumption that OA exhibits its anti-inflammatory properties via modulation of this epigenetic mark. In conclusion, our study strongly suggests that nutritional components can directly affect PdL cells via changes in their epigenetic code. Since epigenetic inhibitors are already widely used clinically, they may hold promise for novel approaches for personalized orthodontic treatment that incorporates nutritional and metabolism-related changes.

Identification of Aloe-derived natural products as prospective lead scaffolds for SARS-CoV-2 main protease (Mpro) inhibitors

In the past two years, the COVID-19 pandemic has caused over 5 million deaths and 250 million infections worldwide. Despite successful vaccination efforts and emergency approval of small molecule therapies, a diverse range of antivirals is still needed to combat the inevitable resistance that will arise from new SARS-CoV-2 variants. The main protease of SARS-CoV-2 (M^pro) is an attractive drug target due to the clinical success of protease inhibitors against other viruses, such as HIV and HCV. However, in order to combat resistance, various chemical scaffolds need to be identified that have the potential to be developed into potent inhibitors. To this end, we screened a high-content protease inhibitor library against M^proin vitro, in order to identify structurally diverse compounds that could be further developed into antiviral leads. Our high-content screening efforts retrieved 27 hits each with > 50% inhibition in our M^pro FRET assay. Of these, four of the top inhibitor compounds were chosen for follow-up due to their potency and drugability (Lipinski's rules of five criteria): anacardic acid, aloesin, aloeresin D, and TCID. Further analysis via dose response curves revealed IC₅₀ values of 6.8 μM, 38.9 μM, 125.3 μM, and 138.0 μM for each compound, respectively. Molecular docking studies demonstrated that the four inhibitors bound at the catalytic active site of M^pro with varying binding energies (-7.5 to -5.6 kcal/mol). Furthermore, M^pro FRET assay kinetic studies demonstrated that M^pro catalysis is better represented by a sigmoidal Hill model than the standard Michaelis-Menten hyperbola, indicating substantial cooperativity of the active enzyme dimer. This result suggests that the dimerization interface could be an attractive target for allosteric inhibitors. In conclusion, we identified two closely-related natural product compounds from the Aloe plant (aloesin and aloeresin D) that may serve as novel scaffolds for M^pro inhibitor design and additionally confirmed the strongly cooperative kinetics of M^pro proteolysis. These results further advance our knowledge of structure-function relationships in M^pro and offer new molecular scaffolds for inhibitor design.

CNSL, a Promising Building Blocks for Sustainable Molecular Design of Surfactants: A Critical Review

Surfactants are crystallizing a certain focus for consumer interest, and their market is still expected to grow by 4 to 5% each year. Most of the time these surfactants are of petroleum origin and are not often biodegradable. Cashew Nut Shell Liquid (CNSL) is a promising non-edible renewable resource, directly extracted from the shell of the cashew nut. The interesting structure of CNSL and its components (cardanol, anacardic acid and cardol) lead to the synthesis of biobased surfactants. Indeed, non-ionic, anionic, cationic and zwitterionic surfactants based on CNSL have been reported in the literature. Even now, CNSL is absent or barely mentioned in specialized review or chapters talking about synthetic biobased surfactants. Thus, this review focuses on CNSL as a building block for the synthesis of surfactants. In the first part, it describes and criticizes the synthesis of molecules and in the second part, it compares the efficiency and the properties (CMC, surface tension, kraft temperature, biodegradability) of the obtained products with each other and with commercial ones.

Phenolic Lipids Derived from Cashew Nut Shell Liquid to Treat Metabolic Diseases

Metabolic diseases are increasing at staggering rates globally. The peroxisome proliferator-activated receptors (PPARα/γ/δ) are fatty acid sensors that help mitigate imbalances between energy uptake and utilization. Herein, we report compounds derived from phenolic lipids present in cashew nut shell liquid (CNSL), an abundant waste byproduct, in an effort to create effective, accessible, and sustainable drugs. Derivatives of anacardic acid and cardanol were tested for PPAR activity in HEK293 cell co-transfection assays, primary hepatocytes, and 3T3-L1 adipocytes. In vivo studies using PPAR-expressing zebrafish embryos identified CNSL derivatives with varying tissue-specific activities. LDT409 (23) is an analogue of cardanol with partial agonist activity for PPARα and PPARγ. Pharmacokinetic profiling showed that 23 is orally bioavailable with a half-life of 4 h in mice. CNSL derivatives represent a sustainable source of selective PPAR modulators with balanced intermediate affinities (EC₅₀ ∼ 100 nM to 10 μM) that provide distinct and favorable gene activation profiles for the treatment of diabetes and obesity.

TRP Channels as Molecular Targets to Relieve Cancer Pain

Transient receptor potential (TRP) channels are critical receptors in the transduction of nociceptive stimuli. The microenvironment of diverse types of cancer releases substances, including growth factors, neurotransmitters, and inflammatory mediators, which modulate the activity of TRPs through the regulation of intracellular signaling pathways. The modulation of TRP channels is associated with the peripheral sensitization observed in patients with cancer, which results in mild noxious sensory stimuli being perceived as hyperalgesia and allodynia. Secondary metabolites derived from plant extracts can induce the activation, blocking, and desensitization of TRP channels. Thus, these compounds could act as potential therapeutic agents, as their antinociceptive properties could be beneficial in relieving cancer-derived pain. In this review, we will summarize the role of TRPV1 and TRPA1 in pain associated with cancer and discuss molecules that have been reported to modulate these channels, focusing particularly on the mechanisms of channel activation associated with molecules released in the tumor microenvironment.

Cashew Nut Shell Liquid (CNSL) as a Source of Drugs for Alzheimer's Disease

Alzheimer's disease (AD) is a complex neurodegenerative disorder with a multifaceted pathogenesis. This fact has long halted the development of effective anti-AD drugs. Recently, a therapeutic strategy based on the exploitation of Brazilian biodiversity was set with the aim of discovering new disease-modifying and safe drugs for AD. In this review, we will illustrate our efforts in developing new molecules derived from Brazilian cashew nut shell liquid (CNSL), a natural oil and a byproduct of cashew nut food processing, with a high content of phenolic lipids. The rational modification of their structures has emerged as a successful medicinal chemistry approach to the development of novel anti-AD lead candidates. The biological profile of the newly developed CNSL derivatives towards validated AD targets will be discussed together with the role of these molecular targets in the context of AD pathogenesis.

Anacardium Occidentale L. Leaf Extracts Protect Against Glutamate/H2O2-Induced Oxidative Toxicity and Induce Neurite Outgrowth: The Involvement of SIRT1/Nrf2 Signaling Pathway and Teneurin 4 Transmembrane Protein

Neurodegenerative diseases are linked to neuronal cell death and neurite outgrowth impairment that are often caused by oxidative stress. Natural products, which have neuroprotective against oxidative stress and neurite outgrowth inducing activity, could be potential candidates for alternative treatment of neurodegenerative diseases. This study aims to investigate the neuroprotective effects and neuritogenesis properties of Anacardium occidentale leaf extracts in cultured neuronal (HT22 and Neuro-2a) cells. We found gallic acid, catechin and quercetin as the main compounds in A. occidentale extracts. The extracts have a protective effect against glutamate/H₂O₂-mediated oxidative stress-induced cell toxicity. The gene expression of cellular antioxidant enzymes (SODs, GPx and, GSTs) were up-regulated by this treatment. The treatment also triggered SIRT, Nrf2 proteins as well as the mRNA transcriptions of relevant anti-oxidation genes (NQO1, GCLM, and EAAT3). We demonstrated that the extracts promote antioxidant defense in neuronal cells via the SIRT1/Nrf2 signaling pathway. Moreover, the extracts increase neurite outgrowth and Ten-4 expression in Neuro-2a cells. However, the neuritogenesis properties did not occur, when Ten-4 expression was knocked down by corresponding siRNA. These results suggest that the leaf extracts have an interesting neuritogenesis and neuroprotective potential against glutamate/H₂O₂-mediated toxicity and could be a potential therapeutic candidate for neurodegenerative diseases.