(−)-α-Bisabolol attenuates visceral nociception and inflammation in mice

Development and Validation of a Gas Chromatography-Mass Spectrometry Method for the Analysis of the Novel Plant-Based Substance with Antimicrobial Activity

The research into new pharmaceutical substances based on essential oils, individual biologically active phytochemicals, and plant extracts is a priority in field of pharmaceutical sciences. A novel multicomponent substance based on Melaleuca alternifolia (M. alternifolia) leaf oil (TTO), 1,8-cineole (eucalyptol), and (-)-α-bisabolol with potent synergetic antimicrobial activity was investigated and suggested for the treatment of seborrheic dermatitis (SD) and dandruff. The objective of this research was to establish and validate a specific, accurate, and precise gas chromatography-mass spectrometry (GC-MS) method for further quantitative and qualitative analysis in order to ensure quality control. The main parameters of validation were suitability, specificity, linearity, accuracy, and intermediate precision according to the European Pharmacopoeia (XI edition), Russian Pharmacopoeia (XIV edition), and some parameters of ICH requirements. The peaks of fifteen chemical phytoconstituents were identified in the test sample solution with the prevalence of (-)-α-bisabolol (27.67%), 1,8-cineole (25.63%), and terpinen-4-ol (16.98%). These phytochemicals in the novel substance were chosen for standardization and validation of the GC-MS method. The chosen chromatographic conditions were confirmed for testing of the plant-based substance in a suitability test. It was established that the GC-MS method provides a significant separation, symmetry of peaks and resolution between phytochemicals. The calibration curves of each phytochemical had good linearity (R2 > 0.999) in five concentrations. In the same concertation range, the accuracy of terpinen-4-ol, 1,8-cineol, and (-)-α-bisabolol determination using the method of additives was 98.3-101.60%; the relative standard deviation (RSD) ranged from 0.89% to 1.51% and corresponded to requirements. The intraday and interday precision was ≤2.56%. Thus, the GC-MS method was validated to be specific, sensitive, linear, accurate, and precise. This GC-MS method could be recommended as a routine analytic technique for multicomponent plant-based substances-enriched terpenes.

Chemical Composition and Antimicrobial Potential of a Plant-Based Substance for the Treatment of Seborrheic Dermatitis

Seborrheic dermatitis (SD) is the most prevalent dermatological disease, occurring in up to 50% of newborns, children, and adults around the world. The antibacterial and antifungal resistance contributed to the search for new natural substances and the development of a novel substance based on Melaleuca alternifolia (M. alternifolia) leaf oil (TTO), 1,8-cineole (eucalyptol), and α-(-)-bisabolol. Thus, this work aimed to determine the chemical composition of the novel plant-based substance and to evaluate its antimicrobial activity against standard microorganisms involved in the pathogenesis of SD. Moreover, the chemical composition of the substance was analyzed by gas chromatography coupled with mass spectrometry (GC/MS). Staphylococcus epidermidis (S. epidermidis), Staphylococcus aureus (S. aureus), Micrococcus luteus (M. luteus), and Candida albicans (C. albicans) were used for antimicrobial and antifungal assays by means of the broth microdilution method to determine the minimal inhibitory concentration (MIC). Finally, the substance’s ability to inhibit Malassezia furfur (M. furfur) was evaluated. Eighteen compounds from different chemical groups were identified by GC/MS. The major biologically active compounds of the substance were terpinen-4-ol (20.88%), 1,8-cineole (22.28%), (-)-α-bisabolol (25.73%), and o-cymene (8.16%). The results showed that the substance has a synergistic antimicrobial and antifungal activity, while S. epidermidis and C. albicans strains were the most susceptible. Furthermore, the substance inhibited M. furfur, which is a main pathogen involved in the pathogenesis of SD and clinical manifestations. It can be concluded that the novel plant-based substance has a promising potential against M. furfur and scalp commensal bacteria and may be helpful for the development of new drugs for treatment of dandruff and SD.

Anti-Inflammatory, Antioxidant, and Skin Regenerative Potential of Secondary Metabolites from Plants of the Brassicaceae Family: A Systematic Review of In Vitro and In Vivo Preclinical Evidence (Biological Activities Brassicaceae Skin Diseases)

The Brassicaceae family constitutes some of the most well-studied natural products in the world, due to their anti-inflammatory, anti-oxidative, and pro-regenerative properties as well as their ubiquitous distribution across the world. To evaluate the potential efficacy of the Brassicaceae family in the treatment of inflammatory skin disorders and wounds, based on preclinical evidence from in vivo and in vitro studies. This systematic review was performed according to the PRISMA guidelines, using a structured search on the PubMed-Medline, Scopus, and Web of Science platforms. The studies included were those that used murine models and in vitro studies to investigate the effect of Brassicaceae on skin disorders. Bias analysis and methodological quality assessments were examined through SYRCLE’s RoB tool. Brassicaceae have shown positive impacts on inflammatory regulation of the skin, accelerating the wound healing process, and inhibiting the development of edema. The studies showed that the Brassicaceae family has antioxidant activity and effects on the modulation of cyclooxygenase 2 and the nuclear factor kappa β (NFκβ) pathway. The secondary metabolites present in Brassicas are polyphenols (68.75%; n = 11), terpenes/carotenoids (31.25%; n = 5), and glycosylates (25%; n = 4), which are responsible for their anti-inflammatory, healing, and antioxidant effects. In addition, the current evidence is reliable because the bias analysis showed a low risk of bias. Our review indicates that compounds derived from Brassicaceae present exceptional potential to treat inflammatory skin diseases and accelerate cutaneous wound healing. We hope that our critical analysis can help to expedite clinical research and to reduce methodological bias, thereby improving the quality of evidence in future research. The registration number on the Prospero platform is CRD42021262953.

Health Benefits, Pharmacological Effects, Molecular Mechanisms, and Therapeutic Potential of α-Bisabolol

α-Bisabolol is one of the important monocyclic sesquiterpenes, derived naturally from essential oils of many edible and ornamental plants. It was first obtained from Matricaria chamomilla, commonly known as chamomile or German chamomile. The available literature indicates that this plant along with other α-Bisabolol containing plants is popularly used in traditional medicine for potential health benefits and general wellbeing. Nutritional studies are indicative of the health benefits of α-Bisabolol. Numerous experimental studies demonstrated pharmacological properties of α-Bisabolol including anticancer, antinociceptive, neuroprotective, cardioprotective, and antimicrobial. This review aims to collectively present different pharmacological activities based on both in vitro and in vivo studies. In the present review using synoptic tables and figures, we comprehensively present that α-Bisabolol possesses therapeutic and protective activities, therefore, it can be used for potential health benefits based on pharmacological effects, underlying molecular mechanism, and favorable pharmaceutical properties. Based on the studies mostly performed on cell lines or animal models, it is evident that α-Bisabolol may be a promising nutraceutical and phytomedicine to target aberrant biological mechanisms which result in altered physiological processes and various ailments. Given the polypharmacological effects and pleiotropic properties, along with favorable pharmacokinetics, and dietary availability and safety, α-Bisabolol can be used as a dietary agent, nutraceutical or phytopharmaceutical agent or as an adjuvant with currently available modern medicines. The regulatory approval of this molecule for use as food additives, and in cosmetics and fragrance industry is also supportive of its human usage. Moreover, further studies are necessary to address pharmaceutical, pharmacological, and toxicological aspects before clinical or nutritional usage in humans. The biological actions and health benefits open opportunities for pharmaceutical development with pharmacological basis of its use in future therapeutics.

The terpenes camphene and alpha-bisabolol inhibit inflammatory and neuropathic pain via Cav3.2 T-type calcium channels

T-type calcium channels are known molecular targets of certain phytocannabinoids and endocannabinoids. Here we explored the modulation of Cav3.2 T-type calcium channels by terpenes derived from cannabis plants. A screen of eight commercially available terpenes revealed that camphene and alpha-bisabolol mediated partial, but significant inhibition of Cav3.2 channels expressed in tsA-201 cells, as well as native T-type channels in mouse dorsal root ganglion neurons. Both compounds inhibited peak current amplitude with IC50s in the low micromolar range, and mediated an additional small hyperpolarizing shift in half-inactivation voltage. When delivered intrathecally, both terpenes inhibited nocifensive responses in mice that had received an intraplantar injection of formalin, with alpha-bisabolol showing greater efficacy. Both terpenes reduced thermal hyperalgesia in mice injected with Complete Freund's adjuvant. This effect was independent of sex, and absent in Cav3.2 null mice, indicating that these compounds mediate their analgesic properties by acting on Cav3.2 channels. Both compounds also inhibited mechanical hypersensitivity in a mouse model of neuropathic pain. Hence, camphene and alpha-bisabolol have a wide spectrum of analgesic action by virtue of inhibiting Cav3.2 T-type calcium channels.

Analgesic Potential of Terpenes Derived from Cannabis sativa

Pain prevalence among adults in the United States has increased 25% over the past two decades, resulting in high health-care costs and impacts to patient quality of life. In the last 30 years, our understanding of pain circuits and (intra)cellular mechanisms has grown exponentially, but this understanding has not yet resulted in improved therapies. Options for pain management are limited. Many analgesics have poor efficacy and are accompanied by severe side effects such as addiction, resulting in a devastating opioid abuse and overdose epidemic. These problems have encouraged scientists to identify novel molecular targets and develop alternative pain therapeutics. Increasing preclinical and clinical evidence suggests that cannabis has several beneficial pharmacological activities, including pain relief. Cannabis sativa contains more than 500 chemical compounds, with two principle phytocannabinoids, Δ9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD). Beyond phytocannabinoids, more than 150 terpenes have been identified in different cannabis chemovars. Although the predominant cannabinoids, Δ9-THC and CBD, are thought to be the primary medicinal compounds, terpenes including the monoterpenes β-myrcene, α-pinene, limonene, and linalool, as well as the sesquiterpenes β-caryophyllene and α-humulene may contribute to many pharmacological properties of cannabis, including anti-inflammatory and antinociceptive effects. The aim of this review is to summarize our current knowledge about terpene compounds in cannabis and to analyze the available scientific evidence for a role of cannabis-derived terpenes in modern pain management. SIGNIFICANCE STATEMENT: Decades of research have improved our knowledge of cannabis polypharmacy and contributing phytochemicals, including terpenes. Reform of the legal status for cannabis possession and increased availability (medicinal and recreational) have resulted in cannabis use to combat the increasing prevalence of pain and may help to address the opioid crisis. Better understanding of the pharmacological effects of cannabis and its active components, including terpenes, may assist in identifying new therapeutic approaches and optimizing the use of cannabis and/or terpenes as analgesic agents.

Acaricidal activity of essential oils of Cinnamomum zeylanicum and Eremanthus erythropappus, major compounds and cinnamyl acetate in Rhipicephalus microplus

This study aimed to chemically characterize the essential oils (EOs) of Cinnamomum zeylanicum (cinnamon) and Eremanthus erythropappus (candeia) and evaluate their acaricidal activity, together with that of their major compounds and cinnamyl acetate derivative, against Rhipicephalus microplus. Essential oil compounds were identified through gas chromatography. The larval packet test (LPT) at concentrations ranging from 0.31 to 10.0 mg/mL and the adult immersion test (AIT) at concentrations between 2.5 and 60.0 mg/mL were performed. (E)-cinnamaldehyde and α-bisabolol were the major compounds in cinnamon (86.93%) and candeia (78.41%) EOs, respectively. In the LPT, the EOs of cinnamon and candeia and the compounds (E)-cinnamaldehyde, α-bisabolol and cinnamyl acetate resulted in 100% mortality at concentrations of 2.5, 2.5, 5.0, 10.0 and 10.0 mg/mL respectively. In the AIT, percentage control values > 95% were observed for cinnamon and candeia EOs, (E)-cinnamaldehyde and α-bisabolol at the concentrations of 5.0, 60.0, 20.0, and 20.0 mg/mL, respectively, whereas cinnamyl acetate showed low activity. We conclude that EOs and their compounds showed high acaricidal activity, whereas the acetylated derivative of (E)-cinnamaldehyde presented less acaricidal activity on R. microplus engorged females.

Production of (-)-α-bisabolol in metabolically engineered Saccharomyces cerevisiae

(-)-α-Bisabolol is a natural monocyclic sesquiterpene alcohol present in German chamomile and has been used as an ingredient of functional foods, cosmetics and pharmaceuticals. In this study, metabolic engineering strategies were attempted to produce (-)-α-bisabolol in Saccharomyces cerevisiae. The codon-optimized MrBBS gene coding for (-)-α-bisabolol synthase from Matricaria recutita was expressed in S. cerevisiae for (-)-α-bisabolol production. The resulting strain (DM) produced 9.5 mg/L of (-)-α-bisabolol in 24 h of batch culture. Additionally, the mevalonate pathway was intensified by introducing a truncated HMG1 gene coding for HMG-CoA reductase and ERG10 encoding acetyl-CoA thiolase. The resulting strain (DtEM) produced a 2.9-fold increased concentration of (-)-α-bisabolol than the DM strain. To increase the acetyl-CoA pool, the ACS1 gene coding for acetyl-CoA synthetase was also overexpressed in the DtEM strain. Finally, the DtEMA strain produced 124 mg/L of (-)-α-bisabolol with 2.7 mg/L-h of productivity in a fed-batch fermentation, which were 13 and 6.8 times higher than the DM strain in batch culture, respectively. Conclusively, these metabolically-engineered approaches might pave the way for the sustainable production of other sesquiterpenes in engineered S. cerevisiae.

Role of the NO-cGMP-K+ channels pathway in the peripheral antinociception induced by α-bisabolol

The aim of this study was to examine if the peripheral antinociception of α-bisabolol involves the participation of nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) synthesis followed by K⁺ channel opening in the formalin test. Wistar rats were injected in the dorsal surface of the right hind paw with formalin (1%). Rats received a subcutaneous injection into the dorsal surface of the paw of vehicles or increasing doses of α-bisabolol (100-300 µg/paw). To determine whether the peripheral antinociception induced by α-bisabolol was mediated by either the opioid receptors or the NO-cGMP-K⁺ channels pathway, the effect of pretreatment (10 min before formalin injection) with the appropriate vehicles, naloxone, naltrexone, N^G-nitro-l-arginine methyl ester (L-NAME), 1H-[1,2,4]-oxadiazolo[4,2-a]quinoxalin-1-one (ODQ), glibenclamide, glipizide, apamin, charybdotoxin, tetraethylammonium, or 4-aminopyridine on the antinociceptive effects induced by local peripheral α-bisabolol (300 µg/paw) were assessed. α-Bisabolol produced antinociception during both phases of the formalin test. α-Bisabolol antinociception was blocked by L-NAME, ODQ, and all the K⁺ channels blockers. The peripheral antinociceptive effect produced by α-bisabolol was not blocked by the opioid receptor inhibitors. α-Bisabolol was able to active the NO-cGMP-K⁺ channels pathway to produce its antinoceptive effect. The participation of opioid receptors in the peripheral local antinociception induced by α-bisabolol is excluded.

Acaricidal activity of (E)-cinnamaldehyde and α-bisabolol on populations of Rhipicephalus microplus (Acari: Ixodidae) with different resistance profiles

This study aimed to investigate the acaricidal activity of (E)-cinnamaldehyde and α-bisabolol on populations of Rhipicephalus microplus with different resistance profiles. The adult immersion test (AIT) was used to characterize the susceptibility of tick populations (50 field populations) to synthetic acaricides: deltamethrin, amitraz, and chlorfenvinphos. The larval packet test (LPT) was used to determine the LC₅₀ values for (E)-cinnamaldehyde (populations 1-25) and α-bisabolol (populations 26-50) at the concentrations of 0.31, 0.62, 1.25, 2.0, 2.5, 5.0 and 10.0 mg/mL. The susceptible strain Porto Alegre (POA) was used as a reference for calculating the resistance ratio (RR). In the AIT, deltamethrin did not show efficacy >95 % for any of the populations, whereas amitraz and chlorfenvinphos have presented efficacy >95 % for three (6 %) and 15 (30 %) populations, respectively. In the LPT, the LC₅₀ values of (E)-cinnamaldehyde and α-bisabolol varied from 0.23 to 2.36 mg/mL and 1.57-3.01 mg/mL, respectively. The RR₅₀ for (E)-cinnamaldehyde showed 20 (80 %) populations with values <1.0 and no population with values>1.5. As for α-bisabolol, only two (8%) populations have presented RR₅₀ <1.0, whereas three (12 %) populations showed incipient resistance to this sesquiterpene (RR₅₀ between 1.5 and 2.0). The results indicate that all studied tick populations showed low susceptibility to at least one of the commercial acaricides tested. In addition, comparison between the LC₅₀ values of (E)-cinnamaldehyde and α-bisabolol for the field populations and the susceptible strain POA suggests that there is no cross-resistance of (E)-cinnamaldehyde and α-bisabolol for the tick populations evaluated, and that the differences in the LC₅₀ values are due to population variations.

Terpenoids as Potential Geroprotectors

Terpenes and terpenoids are the largest groups of plant secondary metabolites. However, unlike polyphenols, they are rarely associated with geroprotective properties. Here we evaluated the conformity of the biological effects of terpenoids with the criteria of geroprotectors, including primary criteria (lifespan-extending effects in model organisms, improvement of aging biomarkers, low toxicity, minimal adverse effects, improvement of the quality of life) and secondary criteria (evolutionarily conserved mechanisms of action, reproducibility of the effects on different models, prevention of age-associated diseases, increasing of stress-resistance). The number of substances that demonstrate the greatest compliance with both primary and secondary criteria of geroprotectors were found among different classes of terpenoids. Thus, terpenoids are an underestimated source of potential geroprotectors that can effectively influence the mechanisms of aging and age-related diseases.

Antiedematogenic and Anti-Inflammatory Activity of the Monoterpene Isopulegol and Its β-Cyclodextrin (β-CD) Inclusion Complex in Animal Inflammation Models

Isopulegol (ISO) is an alcoholic monoterpene widely found in different plant species, such as Melissa officinalis, and has already been reported to have a number of pharmacological properties. Like other terpenes, ISO is a highly volatile compound that is slightly soluble in water, so its inclusion into cyclodextrins (CDs) is an interesting approach to increase its solubility and bioavailability. Thus, our aim was to evaluate the antiedematogenic and anti-inflammatory activity of isopulegol and a β-cyclodextrin-isopulegol inclusion complex (ISO/β-CD) in rodent models. For the anti-inflammatory activity evaluation, antiedematogenic plethysmometry and acute (peritonitis and pleurisy), as well as chronic (cotton pellet-induced granuloma) anti-inflammatory models, were used. The docking procedure is used to evaluate, analyze, and predict their binding mode of interaction with H1 and Cox-2 receptors. The animals (n = 6) were divided into groups: ISO and ISO/β-CD, negative control (saline), and positive control (indomethacin and promethazine). ISO and ISO/β-CD were able to reduce acute inflammatory activity by decreasing albumin extravasation, leukocyte migration, and MPO concentration, and reducing exudate levels of IL-1β and TNF-α. ISO and ISO/β-CD significantly inhibited edematogenic activity in carrageenan- and dextran-induced paw edema. Moreover, both significantly reduced chronic inflammatory processes, given the lower weight and protein concentration of granulomas in the foreign body granulomatous inflammation model. The results suggest that the inclusion of ISO in β-cyclodextrins improves its pharmacological properties, with the histamine and prostaglandin pathways as probable mechanisms of inhibition, and also reinforces the anti-inflammatory profile of this terpene.

Antiparasitic effect of (-)-α-bisabolol against Trypanosoma cruzi Y strain forms

Chagas disease is caused by Trypanosoma cruzi and affects about 7 million people worldwide. Benznidazole and nifurtimox have low efficacy and high toxicity. The present study was designed to identify the trypanocidal effect of (-)-α-Bisabolol (BIS) and investigate its mechanism. Epimastigotes and trypomastigotes were cultured with BIS and the viable cells were counted. BIS antiamastigote effect was evaluated using infected LLC-MK2 cells. MTT assay was performed to evaluate BIS cytotoxicity. Growth recovery was assessed to evaluate BIS effect after short times of exposure. BIS mechanism was investigated through flow cytometry, with 7-AAD and Annexin V-PE. DCFH-DA, rhodamine 123 (Rho123) and acridine orange (AO). Finally, enzymatic and computational assays were performed to identify BIS interaction with T. cruzi GAPDH (tcGAPDH). BIS showed an inhibitory effect on epimastigotes after all tested periods, as well on trypomastigotes. It caused cytotoxicity on LLC-MK2 cells at higher concentrations, with selectivity index (SeI) = 26.5. After treatment, infected cells showed a decrease in infected cells, the number of amastigotes per infected cell and the survival index (SuI). Growth recovery demonstrated that BIS effect causes rapid death of T. cruzi. Flow cytometry showed that BIS biological effect is associated with apoptosis induction, increase in cytoplasmic ROS and mitochondrial transmembrane potential, while reservosome swelling was observed at a late stage. Also, BIS action mechanism may be associated to tcGAPDH inhibition. Altogether, the results demonstrate that BIS causes cell death in Trypanosoma cruzi Y strain forms, with the involvement of apoptosis and oxidative stress and enzymatic inhibition.

Anti-inflammatory and sedative activities of Peperomia galioides: in vivo studies in mice

Aerial parts (leaves, flowers, stem) of Peperomia galioides extract administered to mice, was used to confirm its anti-inflammatory and sedative folk uses. The anti-inflammatory activity was assessed by croton oil-induced ear oedema and myeloperoxidase (acute inflammation); cotton pellet-induced granuloma (sub-acute inflammation) and Escherichia coli Lipopolysaccharide (LPS) induced inflammation (cellular mediators). The sedative activity was studied by the pentobarbital-induced sleeping time test. Single doses (300 and 600 mg/kg; i.p.) of the extract reduced croton oil-induced ear oedema and myeloperoxidase activity. Six days administration of the extract (300 mg/kg, i.p.) to mice implanted with cotton pellets diminished granuloma formation. LPS (20 mg/kg, i.p.) enhanced plasma nitrites and TNF-α levels that were inhibited by the extract. The duration but not the onset of sleeping time was enhanced by 300 and 600 mg/kg of the extract. Our results show that P. galioides has anti-inflammatory and sedative activities in mice, which validates its traditional use.

Enhanced (−)-α-Bisabolol Productivity by Efficient Conversion of Mevalonate in Escherichia coli

(−)-α-Bisabolol, a naturally occurring sesquiterpene alcohol, has been used in pharmaceuticals and cosmetics owing to its beneficial effects on inflammation and skin healing. Previously, we reported the high production of (−)-α-bisabolol by fed-batch fermentation using engineered Escherichia coli (E. coli) expressing the exogenous mevalonate (MVA) pathway genes. The productivity of (−)-α-bisabolol must be improved before industrial application. Here, we report enhancement of initial (−)-α-bisabolol productivity to 3-fold higher than that observed in our previous study. We first harnessed a farnesyl pyrophosphate (FPP)-resistant mevalonate kinase 1 (MvaK1) from an archaeon Methanosarcina mazei (M. mazei) to create a more efficient heterologous MVA pathway that produces (−)-α-bisabolol in the engineered E. coli. The resulting strain produced 1.7-fold higher (−)-α-bisabolol relative to the strain expressing a feedback-inhibitory MvaK1 from Staphylococcus aureus (S. aureus). Next, to efficiently convert accumulated MVA to (−)-α-bisabolol, we additionally overexpressed genes involved in the lower MVA mevalonate pathway in E. coli containing the entire MVA pathway genes. (−)-α-Bisabolol production increased by 1.8-fold with reduction of MVA accumulation, relative to the control strain. Finally, we optimized the fermentation conditions including inducer concentration, aeration and enzymatic cofactor. The strain was able to produce 8.5 g/L of (−)-α-bisabolol with an initial productivity of 0.12 g/L h in the optimal fed-batch fermentation. Thus, the microbial production of (−)-α-bisabolol would be an economically viable bioprocess for its industrial application.

(-)-α-Bisabolol reduces nociception and trigeminal central sensitisation in acute orofacial neuropathic pain induced by infraorbital nerve injury

Neuropathic orofacial pain conditions represent a challenge to diagnose and treat. Natural substances are promising therapeutic options for the control of pain.

AIMS

This study aimed to examine whether (-)-α-bisabolol (BISA), a natural terpene, can attenuate nociceptive behaviour and central sensitisation in a rodent model of trigeminal neuropathic pain.

MATERIALS AND METHODS

Infraorbital nerve transection (IONX) or sham operation was performed in adult male rats. Head withdrawal thresholds as a measure of facial mechanical sensitivity were tested with von Frey monofilaments applied bilaterally to the facial vibrissal pad pre-operatively (baseline) and then post-operatively before and at 60, 120, 240 and 360 min after administration of vehicle control per oris (p.o.) or BISA (200 mg/kg p.o.) (n = 8/group). Effects of BISA or vehicle on the activity of nociceptive neurons recorded in the medullary dorsal horn (MDH) were tested on post - operative day 8-10. ANOVA followed by post-hoc Bonferroni tested for statistically significant differences (p < 0.05) across study groups and time points.

KEY FINDINGS

IONX animals (but not sham or naïve animals) showed post-operative facial mechanical hypersensitivity that was unaffected by vehicle. However, administration of BISA at post-operative day 7 significantly reversed the mechanical hypersensitivity in IONX rats; this effect lasted for at least 6 h. BISA also attenuated IONX-induced central sensitisation of MDH nociceptive neurons, as reflected in reversal of their reduced activation thresholds, increased responses to graded mechanical stimuli and enhanced spontaneous activity.

SIGNIFICANCE

BISA may attenuate nociceptive behaviour and central sensitisation in a rat model of acute trigeminal neuropathic pain.

Molecular mechanism underlying orofacial antinociceptive activity of Vanillosmopsis arborea Baker (Asteraceae) essential oil complexed with β-cyclodextrin

BACKGROUND

Vanillosmopsis arborea Baker has recognized economic value owing to the high content of (-)-α-bisabolol (BISA) in the essential oil of its stem (EOVA). The antinociceptive effect of EVOA has already been demonstrated, and β-cyclodextrin (βCD) is known to improve the analgesic effect of various substances.

PURPOSE

Thus, we aimed to evaluate the orofacial antinociceptive effect of a complex containing EOVA-βCD in rodents.

METHODS

EOVA was obtained by simple hydrodistillation, and the essential oil was complexed with βCD. The animals (n = 6/group) were treated orally with EOVA-βCD (10 or 50 mg/kg), or vehicle (control), and subjected to cutaneous orofacial nociception (formalin, capsaicin, acidic saline or glutamate), corneal (hypertonic saline) or temporomandibular (formalin) tests. The expression of FOS protein was analyzed in the spinal cord. Molecular docking was performed using the 5-HT₃ and M₂ receptors and BISA.

RESULTS

The oral administration of EOVA-βCD reduced nociceptive behaviour. Moreover, EOVA-βCD decreased FOS expression. The molecular docking study indicates that BISA interacts with 5-HT3 and M2 receptors, indicating the potential mechanism of action of the tested compound.

CONCLUSIONS

Our results indicate that EOVA-βCD possesses orofacial antinociceptive effect, indicating that this complex can be used in analgesic drug development.

(-)-α-bisabolol prevents neuronal damage and memory deficits through reduction of proinflammatory markers induced by permanent focal cerebral ischemia in mice

The pathophysiology of ischemic stroke involves multiple events such as inflammation and oxidative stress which will lead to neuronal death and cognitive deficits. The (-)-α-bisabolol is a monocyclic sesquiterpene alcohol found in various plants and mainly in Matricaria chamomilla, which exerts antioxidant, anti-inflammatory, and anti-apoptotic activities. The aim of this work was to investigate the neuroprotective effects of (-)-α-bisabolol in mice underwent permanent occlusion of the middle cerebral artery (pMCAO). Animals were treated with (-)-α-bisabolol (50, 100 and 200 mg/kg/day, orally) or vehicle (3% tween 80) one day before and 1 h after pMCAO and the treatment continued once daily for the following five days. The treatment with (-)-α-bisabolol (100 and 200 mg/kg) significantly reduced the infarcted area and neurological deficits caused by pMCAO. (-)-α-bisabolol at the 200 mg/kg dose increased cell viability and decreased neuronal degeneration, as evaluated by cresyl violet and Fluoro-Jade C stainings, respectively. (-)-α-bisabolol also increased the locomotor activity which was reduced by cerebral ischemia and improved pMCAO-induced working, spatial, object recognition, and aversive memories deficits. (-)-α-bisabolol (200 mg/kg) significantly prevented the increase of myeloperoxidase (MPO) activity, TNF-α immunoreactivity in the temporal cortex, and the increase of iNOS both in the temporal cortex and in the striatum. (-)-α-bisabolol treatment also prevented astrogliosis in these areas. These data showed that (-)-α-bisabolol provides neuroprotective action probably due to its anti-inflammatory activity, although other mechanisms cannot be discarded.

Protective effect of (−)-α-bisabolol on rotenone-induced toxicity in Drosophila melanogaster

(−)-α-Bisabolol (BISA) is a sesquiterpene alcohol, which has several recognized biological activities, including anti-inflammatory, anti-irritant, and antibacterial properties. In the present study, we investigated the influence of BISA (5, 25, and 250 μmol/L) on rotenone (500 μmol/L)-induced toxicity in Drosophila melanogaster for 7 days. BISA supplementation significantly decreased rotenone-induced mortality and locomotor deficits. The loss of motor function induced by rotenone correlated with a significant change in stress response factors; it decreased thiol levels, inhibited mitochondria complex I, and increased the mRNA expression of antioxidant marker proteins such as superoxide dismutase (SOD), catalase (CAT), and the keap1 gene product. Taken together, our findings indicate that the toxicity of rotenone is likely due to the direct inhibition of complex I activity, resulting in a high level of oxidative stress. Dietary supplementation with BISA affected the expression of SOD mRNA only at a concentration of 250 μmol/L, and did not affect any other parameter measured. Our results showed a protective effect of BISA on rotenone-induced mortality and locomotor deficits in Drosophila; this effect did not correlate with mitochondrial complex I activity, but may be related to the antioxidant protection afforded by eliminating superoxide generated as a result of rotenone-induced mitochondrial dysfunction.

Analgesic-Like Activity of Essential Oil Constituents: An Update

The constituents of essential oils are widely found in foods and aromatic plants giving characteristic odor and flavor. However, pharmacological studies evidence its therapeutic potential for the treatment of several diseases and promising use as compounds with analgesic-like action. Considering that pain affects a significant part of the world population and the need for the development of new analgesics, this review reports on the current studies of essential oils’ chemical constituents with analgesic-like activity, including a description of their mechanisms of action and chemical aspects.

Corneal antinociceptive effect of (-)-α-bisabolol

CONTEXT

(-)-α-Bisabolol (BISA) is a sesquiterpene alcohol widely used as scent in cosmetic preparations, perfumes, shampoos, toilet soaps and other toiletries with potential for use in the pharmaceutical area.

OBJECTIVE

To evaluate the corneal antinociceptive efficacy of BISA and to analyze the best solubilizing agent.

MATERIALS AND METHODS

Acute corneal nociception was induced by the local application of hypertonic saline (5 M NaCl; 20 μL) to the corneal surface of Swiss mice (n = 8/group) 60 min after topical treatment with solutions or ointment containing BISA (50-200 mg/mL). The number of eye wipes performed with the ipsilateral forepaw was counted for a period of 30 s. Control groups (vehicles) were included.

RESULTS

BISA (50, 100 or 200 mg/mL) solubilized with Tween 80 did not reduce the number of eye wipes. Animals treated with the ointment (BISA 50, 100 or 200 mg/mL; p < 0.001), as well the solution containing propylene glycol (BISA 100 mg/mL; p < 0.05), showed significant reduction in the number of nociceptive behaviours. Solutions containing propylene glycol and isopropyl myristate had no effects.

DISCUSSION AND CONCLUSION

BISA possess corneal antinociceptive activity. Although the ointment presented antinociceptive effect, it is concluded that BISA when associated with propylene glycol has better potential for corneal nociceptive pain since it is more comfortable to use, leading to greater acceptance by patients.

Evidence for the involvement of TNF-α and IL-1β in the antinociceptive and anti-inflammatory activity of Stachys lavandulifolia Vahl. (Lamiaceae) essential oil and (-)-α-bisabolol, its main compound, in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Stachys lavandulifolia Vahl (Lamiaceae) is a medicinal plant widely used in Turkey and Iranian folk medicine due to its analgesic and anti-inflammatory properties, but little is known about its essential oil.

AIM OF THIS STUDY

We studied the antinociceptive and anti-inflammatory effects of S. lavandulifolia essential oil (EOSl) and (-)-α-bisabolol (BIS), its main compound, in algogen-induced orofacial nociceptive behavior in mice, and assessed the possible involvement of pro-inflammatory cytokines in these profiles.

MATERIALS AND METHODS

The GC-FID and GC-MS analysis of EOSl demonstrated the presence of (-)-α-bisabolol (56.4%), bicyclogermacrene (5.3%), δ-cadinene (4.2%) and spathulenol (2.9%) as the main compounds. Male Swiss mice were pretreated with EOSl (25 or 50mg/kg, p.o.), BIS (25 or 50mg/kg, p.o.), morphine (3mg/kg, i.p.) or vehicle (saline 0.9% with two drops of tween 80, 0.2%), before formalin- (20μl, 2%), capsaicin- (20μl, 2.5µg) or glutamate- (20μl, 25Mm) injection into the right upper lip (perinasal area) in mice. The anti-inflammatory profile of EOSl or BIS (50mg/kg) was assessed by the inflammatory response induced by carrageenan (2% in 0.2mL) in mice (pleurisy model).

RESULTS

Our results showed that p.o. treatment with EOSl and BIS displayed significant inhibitory (p<0.05 or p<0.01 or p<0.001) effects in different orofacial pain tests on mice, but BIS proved to be more effective, significantly reducing nociceptive behavior in all tests including both phases of the formalin test. The analgesic effect is not related to any abnormality since EOSl- or BIS-treated mice exhibited no performance alteration in grip strength. Moreover, EOS1 and BIS exhibited a significant anti-inflammatory effect (p<0.001) in the pleurisy model of inflammation, which seems to be related to a significant reduction (p<0.05) of the pro-inflammatory cytokine TNF-α in BIS treatment, and of the pro-inflammatory cytokine IL-1β (p<0.01) in EOS1 treatment.

CONCLUSION

Our results corroborate the use of S. lavandulifolia in traditional medicine as an analgesic and anti-inflammatory, which seems to be related to (-)-α-Bisabolol, the main compound of EOSl.

Opuntia dillenii cladode: Opuntiol and opuntioside attenuated cytokines and eicosanoids mediated inflammation

ETHANOPHARMACOLOGICAL RELEVANCE

Opuntia dillenii Haw (Nagphana) traditionally used against inflammation. The present study addressed the anti-inflammatory activity of O. dillenii derived methanol extract, fractions and pure compounds and their underlying mechanism of action.

MATERIALS AND METHODS

O. dillenii cladode methanol extract was subjected to vacuum liquid chromatography (VLC) furnishing two main fractions viz (T-1 and -2) leading to isolation of opuntiol (aglycone) and opuntioside (O-glucoside), respectively. Anti-inflammatory activity of extract, fractions, pure compounds and reference drugs were evaluated using: (1) arachidonic acid (AA) and 12-O-tetradecanoyl-phorbol-13-acetate (TPA)-induced ear edema accompanied by histological studies of mice ear sections and phospholipase A2 (PLA2)-induced mice paw edema. (2) Carrageenan and glycogen-induced peritonitis in rodents. In parallel levels of leukotriene B4 (LTB4) and reactive oxygen species (ROS) were also determined via HPLC and fluoroemetrically using 2', 7'-dichlorodihydrofluorescein diacetate (DCFH-DA) dye, respectively. Additionally, levels of prostaglandin E2 (PGE2), tumor necrosis factor (TNF-α), interleukins IL-1β and -6 were measured by ELISA assay.

RESULTS

O. dillenii methanol extract, fractions and pure compounds reduced AA and TPA-induced ear punch weight in a dose dependent fashion. The corresponding IC50 values obtained also suppressed inflammatory features observed histologically. Furthermore, paw edema and peritonitis were also attenuated. Similar to indomethacin and diclofenac sodium, opuntioside reduced PGE2 levels of inflamed ear which was comparatively 1.3× better than opuntiol. However, opuntiol was more potent in reducing LTB4 levels in rat neutrophils with an IC50 value of 19±3.3μΜ, while opuntioside was ineffective. Opuntiol also effectively suppressed ROS (37%) and cytokine levels (TNF-α, IL-1β and -6) by ~50% and comparable to dexamethasone.

CONCLUSIONS

O. dillenii cladodes possess anti-inflammatory properties via inhibition of arachidonic acid metabolites and cytokines. Opuntiol (aglycone) emerged as a dual inhibitor of cyclooxygenase (COX) and lipooxygenase (LOX) pathways. It also suppressed ROS and cytokine levels. However, opuntioside manifested its selectivity towards COX (PGE2) pathway without affecting LTB4 levels. The present report describing the anti-inflammatory activity of opuntiol and opuntioside for the first time thereby, supporting and justifying the traditional use of O. dillenii against inflammation and may serve as lead compound in designing of new anti-inflammatory agents.

Phytochemical Composition, Antifungal and Antioxidant Activity of Duguetia furfuracea A. St.-Hill

Background. Duguetia furfuracea is popular plant used in popular medicine. Hypothesis/Purpose. This claim evaluated the phytochemical composition of the hydroethanolic extract (HEDF), fractions of Duguetia furfuracea, and antioxidant and antifungal activity. Methods. The chemical profile was carried out by HPLC-DAD. The total phenolic contents and flavonoid components were determined by Folin-Ciocalteu and aluminium chloride reaction. The antioxidant activity was measured by scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical and ferric reducing ability of plasma (FRAP) methods. The antifungal activity was determined by microdilution assay. Results. HPLC analysis revealed caffeic acid and rutin as major compounds (HEDF), caffeic acid and quercitrin (Mt-OH fraction), and quercitrin and isoquercitrin (Ac-OEt fraction). The highest levels of phenols and total flavonoids were found for Ac-OEt fraction, and the crude extract showed higher in vitro antioxidant potential. The antifungal activity showed synergic effect with fluconazole and EHDF against C. krusei, fluconazole and Mt-OH against C. krusei and C. tropicalis, and Ac-OE and fluconazole against C. albicans. Conclusion. The highest levels of phenols and total flavonoids were marked with antioxidant effect. This is the first report of bioactivity of the synergic effect of HEDF and fractions. More studies would be required to better clarify its mechanism of synergic action.

Analgesic Potential of Essential Oils

Pain is an unpleasant sensation associated with a wide range of injuries and diseases, and affects approximately 20% of adults in the world. The discovery of new and more effective drugs that can relieve pain is an important research goal in both the pharmaceutical industry and academia. This review describes studies involving antinociceptive activity of essential oils from 31 plant species. Botanical aspects of aromatic plants, mechanisms of action in pain models and chemical composition profiles of the essential oils are discussed. The data obtained in these studies demonstrate the analgesic potential of this group of natural products for therapeutic purposes.

Sesquiterpenes from Essential Oils and Anti-Inflammatory Activity

This review is aimed at presenting relevant information on the therapeutic potential of essential oil sesquiterpenes with anti-inflammatory activity. The data reviewed provide a basis for seeking new anti-inflammatory drugs from natural products that do not exhibit the undesirable side effects often displayed by anti-inflammatory drugs. In this review the experimental models, possible mechanisms of action, and chemical structures of 12 sesquiterpenes are presented.

Inhibitory actions of bisabolol on α7-nicotinic acetylcholine receptors

Bisabolol is a plant-derived monocyclic sesquiterpene alcohol with antinociceptive and antiinflammatory actions. However, molecular targets mediating these effects of bisabolol are poorly understood. In this study, using a two-electrode voltage-clamp and patch-clamp techniques and live cellular calcium imaging, we have investigated the effect of bisabolol on the function of human α7 subunit of nicotinic acetylcholine receptor (nAChR) in Xenopus oocytes, interneurons of rat hippocampal slices. We have found that bisabolol reversibly and concentration dependently (IC50 = 3.1 μM) inhibits acetylcholine (ACh)-induced α7 receptor-mediated currents. The effect of bisabolol was not dependent on the membrane potential. Bisabolol inhibition was not changed by intracellular injection of the Ca(2+) chelator BAPTA and perfusion with Ca(2+)-free solution containing Ba(2+), suggesting that endogenous Ca(2+)-dependent Cl(-) channels are not involved in bisabolol actions. Increasing the concentrations of ACh did not reverse bisabolol inhibition. Furthermore, the specific binding of [(125)I] α-bungarotoxin was not attenuated by bisabolol. Choline-induced currents in CA1 interneurons of rat hippocampal slices were also inhibited with IC50 of 4.6 μM. Collectively, our results suggest that bisabolol directly inhibits α7-nAChRs via a binding site on the receptor channel.

Highly efficient and compatible shampoo for use after hair transplant

Background

Sensitive or hyperreactive skin is a common condition defined by prickling, burning, pain, and pruritus. Although this skin problem was initially described on the face, the scalp is often affected. A sensitive scalp can react with irritation to harsh surfactants or other additives which are often present in shampoos. For this reason, we developed a new rinse-off hypertolerant shampoo specifically designed for the hypersensitive and problematic scalp.

Methods

The shampoo formulation is based on an extremely mild surfactant system and contains bisabolol, an anti-irritant and anti-inflammatory ingredient of chamomile. The shampoo is free of additives such as perfumes, silicones, colorants, parabens, paraffins, and betaine. Since skin can remain in a hyperreactive state after wounding, the status after hair transplantation was chosen as a model system to test the shampoo. Scalp condition and compatibility of each volunteer were analyzed by a plastic surgeon directly after hair transplant and after stitch removal. The plastic surgeons also rated whether they would recommend the further use of the test shampoo. Additionally, volunteers completed a self-assessment questionnaire.

Results

Following hair transplantation, regular use of the shampoo resulted in a significant reduction in the extent of scabbing and erythema. This was confirmed by dermatological scalp examinations performed by the plastic surgeon as well as in volunteers’ self-assessments. The plastic surgeon highly recommended the further use of the test shampoo after hair transplant to all study participants.

Conclusion

Application of the test shampoo demonstrated excellent skin compatibility and product efficacy after hair transplant. The test shampoo significantly reduced the extent of scabs and erythema. Therefore, the shampoo is ideally suited for use after hair transplantation and for the treatment of sensitive scalp. The excellent skin compatibility is because of the mild surfactant system, the calming ingredient bisabolol, and the absence of potentially irritating ingredients.

Animal models of gastrointestinal and liver diseases. Animal models of visceral pain: pathophysiology, translational relevance, and challenges

Visceral pain describes pain emanating from the thoracic, pelvic, or abdominal organs. In contrast to somatic pain, visceral pain is generally vague, poorly localized, and characterized by hypersensitivity to a stimulus such as organ distension. Animal models have played a pivotal role in our understanding of the mechanisms underlying the pathophysiology of visceral pain. This review focuses on animal models of visceral pain and their translational relevance. In addition, the challenges of using animal models to develop novel therapeutic approaches to treat visceral pain will be discussed.

Anti-ulcer activity of essential oil constituents

Essential oils have attracted considerable worldwide attention over the last few decades. These natural products have wide-ranging pharmacological activities and biotechnological applications. Faced with the need to find new anti-ulcer agents and the great effort on the development of drugs for the treatment of ulcers, in this review, the anti-ulcer activities of 21 bioactive compounds found in essential oils are discussed.

An integral topical gel for cellulite reduction: results from a double-blind, randomized, placebo-controlled evaluation of efficacy

BACKGROUND

Cellulite is a serious cosmetic concern for most of the 90% of women affected by it.

OBJECTIVE

To assess the clinical efficacy of a complex integral anti-cellulite gel.

METHODS

This double-blind, randomized, placebo-controlled study involved 44 healthy women, aged 25-55 years. Subjects had a normal to slightly overweight body mass index and presented slight to moderate cellulite on their thighs, buttocks, and/or hips at baseline. Subjects were randomly assigned to either the treated or placebo group and accordingly applied the active product or placebo on their hips, stomach, buttocks, and thighs, twice daily for 3 months. Skin tonicity, orange-peel aspect, and stubborn cellulite were assessed at day 0, 28, 56, and 84. A self-evaluation questionnaire was completed by all volunteers.

RESULTS

At the end of the study, an average of 81% of the subjects applying the active product presented improvement in their cellulite condition versus 32% for the placebo group (all descriptors and sites combined). At day 84, skin tonicity, orange-peel appearance, and stubborn cellulite were improved in a significant manner (P<0.05) over placebo, on all studied areas. Skin tonicity improved on average by +41% for buttocks, +35% for hips, and +31% for thighs. Orange peel appearance was reduced on average by -25% for buttocks, -22% for hips, and -22% for thighs. Stubborn cellulite was reduced on average by -19% for buttocks, -24% for hips, and -22% for thighs. Circumference measurements decreased in a significant manner (P<0.05) over placebo, for the abdomen (average value of -1.1 cm) and thighs (average value of -0.8 cm). The product was well tolerated and perceived by the volunteers themselves as better performing than placebo on all criteria.

CONCLUSION

All results validate the efficacy of the present integral formulation to significantly reduce signs of cellulite and reshape the silhouette.

Topical Antinociceptive Effect of Vanillosmopsis arborea Baker on Acute Corneal Pain in Mice

This study aimed to assess the possible topical antinociceptive activity of Vanillosmopsis arborea Baker essential oil (EOVA) and to clarify the underlying mechanism, using the acute model of chemical (eye wiping) nociception in mice. EOVA (25 to 200 mg/kg; p.o. and topical) evidenced significant antinociception against chemogenic pain in the test model of formalin-induced neuroinflammatory pain. Local application of 5 M NaCl solution on the corneal surface of the eye produced a significant nociceptive behavior, characterized by eye wiping. The number of eye wipes was counted during the first 30 s. EOVA (25, 50, 100, and 200 mg/kg; p.o. and topical) significantly decreased the number of eye wipes. Naloxone, yohimbine, L-NAME, theophylline, glibenclamide, and ruthenium red had no effect on the antinociceptive effect of EOVA. However, ondansetron, p-chlorophenylalanine methyl ester (PCPA), capsazepine, prazosin, and atropine prevented the antinociception induced by EOVA. These results indicate the topical antinociceptive effect of EOVA and showed that 5-HT, α1, TRPV1, and central muscarinic receptors might be involved in the antinociceptive effect of EOVA in the acute corneal model of pain in mice.

Antihyperalgesic and antiedematous activities of bisabolol-oxides-rich matricaria oil in a rat model of inflammation

From the dried flower heads of Matricaria recutita L., essential oil was isolated by hydrodistillation, and in the obtained blue oil, α-bisabolol oxide A (21.5%), α-bisabolol oxide B (25.5%) and (Z)-spiroether (cis-en-yn-spiroether) (10.3%) were identified as the main compounds, by gas chromatography (GC) and GC-mass spectrometry analyses. The antihyperalgesic effects of this oil were examined in a rat model of inflammation induced by carrageenan, through a modified 'paw-pressure' test. Antiedematous effects were examined in a rat model of inflammation induced by carrageenan, dextran and histamine, through plethysmometry. Matricaria oil (25, 50 and 100 mg/kg, p.o.) exhibited a significant dose-dependent reduction of hyperalgesia and edema induced by carrageenan in both prophylactic and therapeutic treatment schemes. It was more efficacious in the prophylactic treatment scheme, and the corresponding median effective dose (ED50 ) ± standard error of the mean (SEM) values were 49.8 ± 6.0 and 42.4 ± 0.2 mg/kg for antihyperalgesic and antiedematous effects, respectively. Prophylactic treatments with matricaria oil (25, 50 and 100 mg/kg, p.o.) caused a significant dose-dependent antiedematous effect in dextran-induced edema with lower efficacy than in the carrageenan model. In a dose of 100 mg/kg, p.o., matricaria oil caused a slight reduction of histamine-induced edema. These results suggest that bisabolol-oxide-rich matricaria oil may be effective against pain and edema present in various inflammatory conditions, which supports matricaria traditional uses.

Phytochemical investigations and bioactivity evaluation of liverworts as a function of anti-inflammatory and antinociceptive properties in animal models

CONTEXT

Liverworts (Marchantiophyta) are the second largest group of bryophytes exhibiting promising pharmacological and biological activities. They have been used as remedies for cuts, fractures, burns, bruises, open wounds, inflammation and pneumonia.

OBJECTIVE

In the present study, eight liverwort species [Corsinia coriandrina (Spreng.) Lindb. (Corsiniaceae), Mannia androgyna (L.) A. Evans (Aytoniaceae), Plagiochasma rupestre (J.R. Forst et G. Forst) Steph. (Aytoniaceae), Porella cordaeana (Huebener) Moore (Porellaceae), Porella platyphylla (L.) Pfeiff. (Porellaceae), Reboulia hemisphaerica (L.) Raddi (Aytoniaceae), Riccia fluitans L. (Ricciaceae), and Targionia hypophylla L. (Targioniaceae)] have been investigated for their phytochemical composition and pharmacological effects as a function of anti-inflammatory and antinociceptive potentials, in connection with the major volatile components of the extracts.

MATERIAL AND METHODS

The chemical compositions of these species and major constituents were identified using GC/MS. In addition, carrageenan-induced paw edema and p-benzoquinone-induced abdominal constriction models were used for the activity assessments.

RESULTS

Sesquiterpenes were detected as common constituents of all liverworts. The in vivo experimental models revealed that P. cordeana, P. rupestre and R. haemispherica show significant inhibitory effect on carrageenan-induced paw edema with the inhibition values of 25.4, 27.2 and 29.4%, respectively. Porella cordaeana, P. platyphylla, P. rupestre and R. haemispherica exhibit promising suppressing effect on p-benzoquinone-induced abdominal constriction animal models with the values of 27.6, 31.5, 44.6, and 41.1%, respectively.

DISCUSSION

It is suggested that the sesquiterpenes are partly responsible for mentioned activities of the liverworts.

CONCLUSION

The present study confirms the claimed anti-inflammatory activity of liverworts in a scientific platform.

UV filters, ingredients with a recognized anti-inflammatory effect

BACKGROUND

To explain observed differences during SPF determination using either an in vivo or in vitro method, we hypothesized on the presence of ingredients having anti-inflammatory properties.

METHODOLOGY/PRINCIPAL FINDINGS

To research our hypothesis, we studied the 21 UV filters both available on the market and authorized by European regulations and subjected these filters to the phorbol-myristate-acetate test using mice. We then catalogued the 13 filters demonstrating a significant anti-inflammatory effect with edema inhibition percentages of more than 70%. The filters are: diethylhexyl butamido triazone (92%), benzophenone-5 and titanium dioxide (90%), benzophenone-3 (83%), octocrylène and isoamyl p-methoxycinnamate (82%), PEG-25 PABA and homosalate (80%), octyl triazone and phenylbenzimidazole sulfonic acid (78%), octyl dimethyl PABA (75%), bis-ethylhexyloxyphenol methoxyphenyl triazine and diethylamino hydroxybenzoyl hexylbenzoate (70%). These filters were tested at various concentrations, including their maximum authorized dose. We detected a dose-response relationship.

CONCLUSIONS/SIGNIFICANCE

The anti-inflammatory effect of a sunscreen ingredient may affect the in vivo SPF value.

Attenuation of visceral nociception by α-bisabolol in mice: investigation of mechanisms

Background

We previously described the visceral antinociceptive property of α-bisabolol (BISA) in mouse models of visceral nociception induced by cyclophosphamide and mustard oil (MO). This study examined the effect of BISA in mouse models of visceral nociception induced by acetic acid, capsaicin, formalin, and the contribution of the nitric oxide system, α₂, K_ATP, 5-HT₃ and TRPV1 receptors to the effect of BISA on MO-evoked nociceptive behaviors. Mice were pretreated orally with BISA (50, 100 and 200 mg/kg) or vehicle, and the pain-related behavioral responses to intraperitoneal administration of acetic acid or intracolonic injection of MO were analyzed.

Results

BISA significantly suppressed the nociceptive behaviors in a dose-unrelated manner. The antinociceptive effect of BISA (50 mg/kg) was show to be glibenclamide resistant, but it was not blocked by pretreatment with the other antagonists tested. In the open-field test that detects sedative or motor abnormality, mice received 50 mg/kg BISA did not show any per se influence in ambulation frequency.

Conclusions

However, their precise antinociceptive mechanisms of action have not been determined.

In-vitro characterization of the pharmacological effects induced by (-)-α-bisabolol in rat smooth muscle preparations

The present study deals with the pharmacological effects of the sesquiterpene alcohol (-)-α-bisabolol on various smooth-muscle preparations from rats. Under resting tonus, (-)-α-bisabolol (30-300 µmol/L) relaxed duodenal strips, whereas it showed biphasic effects in other preparations, contracting endothelium-intact aortic rings and urinary bladder strips, and relaxing these tissues at higher concentrations (600-1000 µmol/L). In preparations precontracted either electromechanically (by 60 mmol/L K(+)) or pharmacomechanically (by phenylephrine or carbachol), (-)-α-bisabolol showed only relaxing properties. The pharmacological potency of (-)-α-bisabolol was variable, being higher in mesenteric vessels, whereas it exerted relaxing activity with a lesser potency on tracheal or colonic tissues. In tissues possessing spontaneous activity, (-)-α-bisabolol completely decreased spontaneous contractions in duodenum, whereas it increased their amplitude in urinary bladder tissue. Administered in vivo, (-)-α-bisabolol attenuated the increased responses of carbachol in tracheal rings of ovalbumin-sensitized rats challenged with ovalbumin, but was without effect in the decreased responsiveness of urinary bladder strips in mice treated with ifosfamide. In summary, (-)-α-bisabolol is biologically active in smooth muscle. In some tissues, (-)-α-bisabolol preferentially relaxed contractions induced electromechanically, especially in tracheal smooth muscle. The findings from tracheal rings reveal that (-)-α-bisabolol may be an inhibitor of voltage-dependent Ca(2+) channels.

Antitumor effects of α-bisabolol against pancreatic cancer

In the present study, we investigated whether α-bisabolol, a sesquiterpene alcohol present in essential oils derived from a variety of plants, has antitumor effects against pancreatic cancer. α-Bisabolol induced a decrease in cell proliferation and viability in pancreatic cancer cell lines (KLM1, KP4, Panc1, MIA Paca2), but not in pancreatic epithelial cells (ACBRI515). α-Bisabolol treatment induced apoptosis and suppressed Akt activation in pancreatic cancer cell lines. Furthermore, α-bisabolol treatment induced the overexpression of early growth response-1 (EGR1), whereas EGR1 siRNA decreased the α-bisabolol-induced cell death of KLM1 cells. Tumor growth in both subcutaneous and peritoneal xenograft nude mouse models was significantly inhibited by intragastric administration of 1000 mg/kg of α-bisabolol, once a week for three weeks. The results indicate that α-bisabolol could be a novel therapeutic option for the treatment of pancreatic cancer.

Inhibitory effects of (-)-α-bisabolol on LPS-induced inflammatory response in RAW264.7 macrophages

Although (-)-α-bisabolol, a natural monocyclic sesquiterpene alcohol, is often used as a cosmetic soothing supplement, little is known about its mechanisms of anti-inflammatory effects. Therefore, this study was designed to investigate anti-inflammatory effects of (-)-α-bisabolol and its mechanisms of action. In this study, we found that (-)-α-bisabolol inhibited lipopolysaccharide (LPS)-induced production of nitric oxide (NO) and prostaglandin E(2) (PGE(2)) in RAW264.7 cells. In addition, expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) genes was reduced, as evidenced by Western blot and luciferase reporter assays for COX-2 and iNOS. To assess the mechanism of the anti-inflammatory property of (-)-α-bisabolol, its effects on the activity of AP-1 and NF-κB promoters were examined. LPS-induced activation of AP-1 and NF-κB promoters was significantly reduced by (-)-α-bisabolol. Consistently, (-)-α-bisabolol reduced LPS-induced phosphorylation of IκBα. In addition, while LPS-induced phosphorylation of ERK and p38 was attenuated by (-)-α-bisabolol, significant changes in the level of phosphorylated JNK were not observed. Our results indicate that (-)-α-bisabolol exerts anti-inflammatory effects by downregulating expression of iNOS and COX-2 genes through inhibition of NF-κB and AP-1 (ERK and p38) signaling.