Gaultherin, a natural salicylate derivative from Gaultheria yunnanensis: Towards a better non-steroidal anti-inflammatory drug

A comparative metabolomics analysis of phytochemcials and antioxidant activity between broccoli floret and by-products (leaves and stalks)

Leaves and stalks, which account for about 45% and 25% of broccoli biomass, respectively, are usually discarded during broccoli production, leading to the waste of green resources. In this study, the phytochemical composition and antioxidant capacity of broccoli florets and their by-products (leaves and stalks) were comprehensively analyzed. The metabolomics identified several unique metabolites (e.g., scopoletin, Harpagoside, and sinalbin) in the leaves and stalks compared to florets. Notably, the leaves were found to be a rich source of flavonoids and coumarins, with superior antioxidant capacity. The random forest model and correlation analysis indicated that flavonoids, coumarin, and indole compounds were the important factors contributing to the antioxidant activity. Moreover, the stalks contained higher levels of carbohydrates and exhibited better antioxidant enzyme activity. Together, these results provided valuable data to support the comprehensive utilization of broccoli waste, the development of new products, and the expansion of the broccoli industry chain.

Phytochemistry and Biological Profile of Gaultheria procumbens L. and Wintergreen Essential Oil: From Traditional Application to Molecular Mechanisms and Therapeutic Targets

Gaultheria procumbens L. is a medicinal plant whose aerial parts (leaves, stems, and fruits) and methyl salicylate-rich essential oil (wintergreen oil) are used in phytotherapy to treat inflammation, muscular pain, and infection-related disorders. This overview summarises the current knowledge about ethnobotany, phytochemistry, pharmacology, molecular mechanisms, biocompatibility, and traditional use of G. procumbens and the wintergreen oil distilled from different plant organs. Over 70 hydrophilic compounds, including methyl salicylate glycosides, flavonoids, procyanidins, free catechins, caffeoylquinic acids, and simple phenolic acids, have been identified in G. procumbens plant parts. Moreover, aliphatic compounds, triterpene acids, and sterols have been revealed in lipophilic fractions. Furthermore, over 130 volatile compounds have been detected in wintergreen oil with dominating methyl salicylate (96.9-100%). The accumulated research indicates that mainly hydrophilic non-volatiles are responsible for the pharmacological effects of G. procumbens, primarily its potent anti-inflammatory, antioxidant, and photoprotective activity, with mechanisms verified in vitro and ex vivo in cellular and cell-free assays. The biological effectiveness of the dominant methyl salicylate glycoside-gaultherin-has also been confirmed in animals. Wintergreen oil is reported as a potent anti-inflammatory agent exhibiting moderate antioxidant and antimicrobial activity in vitro and significant insecticidal and larvicidal capacity. Together, G. procumbens accumulate a diverse fraction of polyphenols, triterpenes, and volatiles with validated in vitro and ex vivo biological activity but with the absence of in vivo studies, especially clinical trials concerning effective dose determination and toxicological verification and technological research, including drug formulation.

Piperine suppresses inflammatory fibroblast-like synoviocytes derived from rheumatoid arthritis patients Via NF-κB inhibition

Rheumatoid Arthritis (RA) is a common autoimmune disease recognized by hyperplasia of synoviocytes and chronic joint inflammation. Activation of fibroblast-like synoviocytes (FLSs) is one of the main features of RA which can trigger inflammation leading to articular cartilage and joint destruction. Aberrant activation of NF-κB signaling cascade was found to be responsible for the high proliferation and defective apoptosis of FLSs and subsequent inflammation in RA. Piperine is a principal constituent of piper species frequently used as antitumor and anti-inflammatory natural compound. In this study we aimed to assess the anti-inflammatory effect of piperine on RA-FLS through NF-κB inhibition. FLSs were isolated from 68 RA patients and 30 healthy controls and were exposed to piperine. The main assays were MTT assay, flow cytometric analysis, PI staining, reverse transcription-PCR (RT-PCR), and ELISA. Results showed that piperine can induce the apoptosis and reduce the proliferation of RA-FLSs in vitro. Moreover, piperine directly reduced the phosphorylation of NF-kB and the expression of NF-κB target genes related to RA-FLSs proliferation (c-Myc and Cycline D1), apoptosis inhibition (Bcl2 and Bcl-xl) and inflammation (COX2, IL-1β, TNF-α,IL-6, CCL5 and CXCL10) while increasing the expression of apoptosis related ones (Bax) in vitro. Piperine also reduced the protein levels of cytokines and chemokines secreted by FLSs as a result of NF-κB inhibition. In conclusion, our results provide evidence for the anti-inflammatory capacity of piperine through inhibition of NF-κB pathway in FLSs proposing this compound as a suitable alternative for chemical treatment of RA.

Biotransformation and metabolism of three methyl salicylate glycosides by gut microbiota in vitro

MSTG-A, MSTG-B and Gualtherin are three natural methyl salicylate glycosides isolated from Dianbaizhu (Gaultheria leucocarpa var. yunnanensis), which is a traditional Chinese folk medicine widely used for the treatment of rheumatoid arthritis. They share the same mother nucleus with aspirin, exhibit similar activity and have fewer side effects. In this study, the incubation of MSTG-A, MSTG-B and gaultherin monomers with human fecal microbiota (HFM), microbiota in 4 intestinal segments (jejunum, ileum, cecal, and colon) and feces of rats in vitro was carried out to comprehensively and meticulously understand their metabolism by gut microbiota (GM) in the body. MSTG-A, MSTG-B and Gualtherin were hydrolyzed by GM to lose glycosyl moieties. The quantity and position of xylosyl moiety significantly affected the rate and extent of the three components being metabolized. The -glc-xyl fragments of these three components could not be hydrolyzed and broken by GM. In addition, the existence of terminal xylosyl moiety prolonged the degradation time. Different results appeared in metabolism of the three monomers by microbiota of different intestinal segments and feces due to the alternation of the species and abundance of microorganisms along the longitudinal axis of the intestinal lumen. Cecal microbiota had strongest degradation ability on these three components. The metabolic details of GM on MSTG-A, MSTG-B and Gualtherin were clarified in this study, providing data support and basis for clinical development and bioavailability improvement.

In vitro, in vivo and in silico evaluation of analgesic, anti-inflammatory, and anti-pyretic activity of salicylate rich fraction from Gaultheria trichophylla Royle (Ericaceae)

ETHNOPHARMACOLOGICAL RELEVANCE

Medicinal properties of Gaultheria have been used in traditional medicine to treat pain and inflammation.

AIM OF THE STUDY

Hence, the purpose of this study was to evaluate the analgesic, antipyretic, and anti-inflammatory properties of Gaultheria trichophylla Royle extract and salicylate-rich fraction in vivo, in vitro, and in silico.

MATERIALS AND METHODS

In vivo analgesic, antipyretic, and anti-inflammatory of extract and a salicylate-rich fraction (at doses of 100, 200, 300, and 150 mg/kg) were assessed using healthy albino mice employing acetic acid-induced writhing, tail immersion test, carrageenan-induced inflammation, and croton oil-induced edema. For in vitro testing of extracts COX and LOX enzyme inhibition assays were used. Molecular docking studies were conducted for in silico testing of the inhibitory activity of the dominant compound Gaultherin against COX and LOX.

RESULTS

G-EXT 200 and 300 and G-SAL 150 mg/kg reduced pyrexia significantly (P < 0.05 and P < 0.01). G-EXT-200, 300, and G-SAL 150 reduce the writing to a significant level (p > 0.05, p < 0.01). G-EXT 200 and 300 and G-SAL 150 mg/kg doses the analgesic effect was significant (p > 0.05, p > 0.01) and was comparable to tramadol. G-EXT 100 200, 300 mg/kg showed 43.8%, 47.94% and 56% respectively. G-SAL 150 mg, rich in salicylates, showed maximum inhibition of 65.75% next to standard drug diclofenac with 76.7% inhibition. G-EXT 100 and 200 mg/kg dose showed significant (p < 0.05) reduction in ear edema. With 300 mg/kg dose the effect was more (61.89%, p < 0.01). The salicylate-rich fraction G-SAL and Celecoxib showed an almost similar effect (p < 0.01). Significance inhibition was shown in the COX-2 test (G-EXT 39.70 and G-SAL 77.20 IC50 μg/ml) and in the 5-LOX test (G-EXT 28.3 and G-SAL 39.70 IC50 μg/ml). The preliminary in silico results suggest that the investigated compound showed excellent inhibitory activity against COX and LOX enzymes as evident from the free binding energy. Molecular docking revealed that Gaultherin binds well in the COX and LOX enzyme catalytic region.

CONCLUSION

The extract and salicylate-rich fraction obtained from G. trichophylla showed significant analgesic, anti-inflammatory, and antipyretic effects in vivo, in vitro, and in silico assays that support its use in traditional medicine.

The impact of Lidocaine gel on TNF-α expression in surgically induced oral mucosal ulcers: an immunohistochemical analysis in rabbits

Background: Besides being a local anesthetic agent lidocaine is a promising anti-inflammatory agent with limited studies on its effect on the mucosa. Aim: Assess the anti-inflammatory effect of lidocaine following surgical induction wound in the oral mucosa as assessed by tumor necrosis factor-α (TNF-α) expression. Materials and methods: The study was conducted on 32 albino rabbits that were categorized into 2 equal groups of 16 rabbits: In the control group an oral wound was surgically induced and left without treatment and in the treatment group an oral wound was surgically induced and received topical Lidocaine gel. Euthanasia of animals was carried out on days 1, 3, 7, and 10, and sample sites were processed for histopathological and immunohistochemical staining for TNF-α. Results: In the histological observations, it was noticed that the healing process was more rapid and convenient in the test group compared to the control group. For Immunohistochemical assessment, the TNF-α started to express clearly at 1 day and gradually decreased and disappeared at 10 days with a superior effect of the lidocaine group over the control group. Conclusion: Lidocaine seems to have anti-inflammatory reactions by lowering TNF-α levels and preventing the production of pro-inflammatory cytokines.

Pharmacokinetics Study of Jin-Gu-Lian Prescription and Its Core Drug Pair (Sargentodoxa cuneata (Oliv.) Rehd. et W and Alangium chinense (Lour.) Harms) by UPLC-MS/MS

Jin-Gu-Lian (JGL) is traditionally used by Miao for the treatment of rheumatism arthralgia. At the same time, the combination of Sargentodoxa cuneata (Oliv.) Rehd. et W (SC) and Alangium chinense (Lour.) Harms (AC), the core drug pair (CDP) in the formula of JGL, is used at high frequencies in many Miao medicine prescriptions for rheumatic diseases. However, previous research lacks the pharmacokinetic study of JGL, and study on the compatibility of its CDP with other medicinal herbs in the formula is needed. This study aims to establish a simple, rapid, and sensitive Ultra Performance Liquid Chromatography Tandem Mass Spectrometry (UPLC-MS/MS) method for the simultaneous determination of four main bioactive components of JGL in rat plasma, including Salidroside (Sal), Anabasine (Ana), Chlorogenic Acid (CA), and Protocatechuic Acid (PCA), and compare the pharmacokinetic properties of two groups of rats after being orally administrated with JGL and its CDP extracts, respectively. The results showed that area under the plasma concentration-time curve (AUC), mean retention time (MRT), and clearance rate (CL), of Sal, Ana, CA and PCA in the two groups of rats were changed in different degrees. The CDP combined with other drugs could significantly increase the absorption of Sal and Ana, prolong its retention time in vivo, and may accelerate the absorption rate of CA and PCA. This indicated that the combination of CDP and other herbs may affect the pharmacokinetics process of active components in vivo, increase the exposure and bioavailability of compounds in the JGL group, and prolong the retention time, which may be the reason why JGL has a better inhibitory effect on inflammatory cytokines, providing a viable orientation for the compatibility investigation of herb medicines.

The Effect of Standardised Leaf Extracts of Gaultheria procumbens on Multiple Oxidants, Inflammation-Related Enzymes, and Pro-Oxidant and Pro-Inflammatory Functions of Human Neutrophils

The leaves of Gaultheria procumbens are polyphenol-rich traditional medicines used to treat inflammation-related diseases. The present study aimed to optimise the solvent for the effective recovery of active leaf components through simple direct extraction and verify the biological effects of the selected extract in a model of human neutrophils ex vivo. The extracts were comprehensively standardised, and forty-one individual polyphenols, representing salicylates, catechins, procyanidins, phenolic acids, and flavonoids, were identified by UHPLC–PDA–ESI–MS³. The chosen methanol–water (75:25, v/v) extract (ME) was obtained with the highest extraction yield and total phenolic levels (397.9 mg/g extract’s dw), including 98.9 mg/g salicylates and 299.0 mg/g non-salicylate polyphenols. In biological tests, ME revealed a significant and dose-dependent ability to modulate pro-oxidant and pro-inflammatory functions of human neutrophils: it strongly reduced the ROS level and downregulated the release of pro-inflammatory cytokines and tissue remodelling enzymes, especially IL-1β and elastase 2, in cells stimulated by fMLP, LPS, or fMLP + cytochalasin B. The extracts were also potent direct scavengers of in vivo relevant oxidants (O₂^•−, ^•OH, and H₂O₂) and inhibitors of pro-inflammatory enzymes (cyclooxygenase-2, hyaluronidase, and lipoxygenase). The statistically significant correlations between the tested variables revealed the synergic contribution of individual polyphenols to the observed effects and indicated them as useful active markers for the standardisation of the extract/plant material. Moreover, the safety of ME was confirmed in cytotoxicity tests. The obtained results might partially explain the ethnomedicinal application of G. procumbens leaves and support the usage of the standardised leaf extract in the adjuvant treatment of oxidative stress and inflammation-related chronic diseases.

Intestinal metabolism and absorption mechanism of multi-components in Gaultheria leucocarpa var. yunnanensis - An assessment using in situ and in vitro models, comparing gut segments in pathological with physiological conditions

ETHNOPHARMACOLOGICAL RELEVANCE

Dianbaizhu (Gaultheria leucocarpa var. yunnanensis) as a Chinese folk medicine exerts significant treatment effects on rheumatoid arthritis (RA) with a long historical time. Our previous reports showed that the anti-rheumatic arthritis fraction (ARF) extracted and enriched from Dianbaizhu possessed good druggability, which was better than its single active ingredients. However, the intestinal transport characteristics and mechanism of ARF have not been elucidated to date.

AIM OF THE STUDY

In order to illustrate the role of active ingredients of ARF in alleviating RA and promoting the development of dosage forms, the intestinal metabolism, absorption properties and mechanism of ARF in vitro and in situ models were investigated.

MATERIALS AND METHODS

Firstly, after incubating with 4 intestinal segments (duodenum, jejunum, ileum, and colon), 7 key components in ARF, including MATG-B, (+)-catechin, MSTG-A, Gaultherin, chlorogenic acid, quercetin, and kaempferol were quantitatively analyzed by a high-performance liquid chromatography (HPLC). Secondly, combining the physiological and pathological rats, the in situ single-pass intestinal perfusion and in vitro everted gut sacs of rats were performed to investigate the absorption features and transport mechanisms of ARF using HPLC and HPLC-Q-TOF-MS/MS. Subsequently, in situ studies were employed to determine the effect of P-glycoprotein (P-gp) inhibitor (verapamil) on the transport characteristics of ARF in RA model rats.

RESULTS

Comparing the absorption parameters of ARF incubated in different intestinal segments, data showed that the absorption of ARF in the small intestine was significantly stronger than that of the colon (P < 0.01). The number of characterized prototype components was subjected to the incubation time, drug concentration and rat body condition, but not the intestinal segments. There were no significant differences in the number of metabolites among different intestinal segments, administration concentrations and incubation time. The best small intestinal absorption site of ARF was duodenum and ileum in normal and model rats, respectively. The P_eff values of 7 index compounds were all higher than 0.2 × 10^-4cm/s, and the F_a values of 7 index compounds were all greater than 20% in the in situ perfusion investigation. The results showed that MSTG-B, MSTG-A and Gaultherin were likely to be substrates of P-gp as verapamil significantly enhanced their P_eff and K_a values, while other ingredients were not P-gp substrates.

CONCLUSIONS

The intestinal membrane permeability of ARF was good. Its intestinal absorption mechanisms mainly involved active transportation processes and passive diffusion. Besides, this report provided data support and basis for clinical development, bioavailability improvement and formulation design.

Screening for the Active Anti-Inflammatory and Antioxidant Polyphenols of Gaultheria procumbens and Their Application for Standardisation: From Identification through Cellular Studies to Quantitative Determination

Aerial parts, leaves, and stems of Gaultheria procumbens are polyphenol-rich herbal medicines with anti-inflammatory and antioxidant effects. The present study focused on identifying active markers of the G. procumbens extracts in an integrated approach combining phytochemical and biological capacity tests. The target compounds, representing all classes of Gaultheria polyphenols, were pre-selected by LC-ESI-PDA-MS/MS. For unambiguous identification, the key analytes, including a rare procyanidin trimer (cinnamtannin B-1), miquelianin potassium salt, and two new natural products: quercetin and kaempferol 3-O-β-d-xylopyranosyl-(1→2)-β-d-glucuronopyranosides, were isolated by preparative HPLC and investigated by spectroscopy (HR-ESI-MS, UV-vis, CD, 1D- and 2D-NMR), thiolysis, flame photometry, optical rotation experiments, and absolute configuration studies. The significant contribution of the pre-selected compounds to the biological effects of the extracts was confirmed in vitro: the analytes significantly and in a dose-dependent manner down-regulated the pro-oxidant and pro-inflammatory functions of human neutrophils ex vivo (inhibited the release of reactive oxygen species, IL-1β, TNF-α, and neutrophils elastase, ELA-2), inhibited two key pro-inflammatory enzymes (cyclooxygenase, COX-2, and hyaluronidase), and most of them, except gaultherin, exerted potent direct antioxidant activity (ferric reducing antioxidant power and superoxide anion scavenging capacity). Moreover, cellular safety was confirmed for all compounds by flow cytometry. Eventually, as these mechanisms have been connected to the health benefits of G. procumbens, 11 polyphenols were accepted as active markers, and a simple, accurate, reproducible, and fully validated RP-HPLC-PDA method for standardisation of the target extracts was proposed.

Lidocaine attenuates CFA-induced inflammatory pain in rats by regulating the MAPK/ERK/NF-κB signaling pathway

Lidocaine is a commonly used local anesthetic that also confers analgesic effects, resistance to hyperalgesia and anti-inflammatory properties. The present study aimed to explore the effects of lidocaine on complete Freund's adjuvant (CFA)-induced inflammatory pain. In the present study, rats were subcutaneously injected with CFA to investigate the molecular mechanisms associated with lidocaine in an inflammation-induced pain model. Firstly, CFA was subcutaneously injected into the paws of Sprague-Dawley rats, following which lidocaine or saline and the ERK agonist recombinant human epidermal growth factor (rh-EGF) were injected via the tail vein. Rat behavior was then assessed at 0 and 4 h, 1, 4, 7 and 14 days after CFA treatment. Proinflammatory cytokine levels in the serum were measured using ELISA. Western blotting was performed to detect the protein levels of phosphorylated (p)-ERK1/2, ERK1/2 and NF-κB subunits p-p65 and p65. Reverse transcription-quantitative PCR was used to measure the mRNA expression of ERK1/2 and p65 in rat spinal cord tissues. The results showed that injection of CFA significantly reduced the mechanical withdrawal threshold, thermal withdrawal latency and the frequency of responses to cold stimulation in rats, whilst promoting tumor necrosis factor-α, interleukin (IL)-1β, IL-6 levels in addition to ERK1/2, p65 protein phosphorylation. These effects were alleviated by lidocaine treatment. Furthermore, treatment with rh-EGF reversed the protective effects of lidocaine on inflammatory pain caused by CFA. In conclusion, lidocaine inhibits the inflammatory response and pain through the MAPK/ERK/NF-κB pathway in a rat model of pain induced by CFA.

Protective effects of dried mature Citrus unshiu peel (Chenpi) and hesperidin on aspirin-induced oxidative damage

Here we investigated the inhibitory effects in rats of mature Citrus unshiu peel (Chenpi) and its component hesperidin on aspirin-induced oxidative damage. The content of hesperidin in Chenpi extract was approximately 11.4%. Wistar rats were orally administered Chenpi extract or hesperidin (20 mg/kg body weight) and then were orally administered aspirin (200 mg/kg body weight) to induce oxidative damage to the stomach, liver, and kidneys. Such damage was evaluated using the formamidopyrimidine DNA glycosylase-modified comet assay. We also measured the amount of the oxidative marker 8-oxo-7,8-dihydroguanine (8-oxodG) in the stomach. Aspirin-induced damage to the gastric mucosa was evaluated using a bleeding score. Chenpi extract and hesperidin significantly inhibited aspirin-induced oxidative DNA damage. The bleeding score of the aspirin-induced gastric mucosa was significantly reduced by treatment with Chenpi extract and hesperidin. To investigate the effects of Chenpi extract and hesperidin on the analgesic effect of aspirin on ddY mice, we employed the acetic acid-induced writhing response test. Chenpi extract and hesperidin did not significantly affect the analgesic effect of aspirin. These results suggest that Chenpi extract and hesperidin significantly inhibit aspirin-induced gastric mucosal damage.

Biological and chemical insight into Gaultheria procumbens fruits: a rich source of anti-inflammatory and antioxidant salicylate glycosides and procyanidins for food and functional application

The fruits of Gaultheria procumbens are traditionally used for culinary and healing purposes as anti-inflammatory agents. In the present work, the active components of the fruits were identified (UHPLC-PDA-ESI-MS3, preparative HPLC isolation, and NMR structural studies), and their biological capacity was evaluated in vitro in cell-based and non-cellular models. The fruits were revealed to be the richest known dietary source of salicylates (38.5 mg per g fruit dw). They are also rich in procyanidins (28.5 mg per g fruit dw). Among five tested solvents, acetone was the most efficient in concentrating the phenolic matrix (39 identified compounds; 191.3 mg g-1, 121.7 mg g-1, and 50.9 mg g-1 dry extract for total phenolics, salicylates, and procyanidins, respectively). In comparison to positive controls (dexamethasone, indomethacin, and quercetin), the extract (AE) and pure salicylates exhibited strong inhibitory activity towards pro-inflammatory enzymes (cyclooxygenase-2 and hyaluronidase). The analytes were found to be non-cytotoxic (flow cytometry) towards human neutrophils ex vivo. Moreover, they significantly, in a dose-dependent manner, downregulated the release of ROS, TNF-α, IL-1β, and elastase-2 and slightly inhibited the secretion of IL-8 and metalloproteinase-9 in the cells. The observed effects might support the usage of G. procumbens fruits as functional components of an anti-inflammatory diet and indicate the potential of AE for use in adjuvant treatment of inflammatory disorders cross-linked with oxidative stress and associated with the excessive production of TNF-α, IL-1β, and elastase-2.

The analgesic potential of glycosides derived from medicinal plants

Pain represents an unpleasant sensation linked to actual or potential tissue damage. In the early phase, the sensation of pain is caused due to direct stimulation of the sensory nerve fibers. On the other hand, the pain in the late phase is attributed to inflammatory mediators. Current medicines used to treat inflammation and pain are effective; however, they cause severe side effects, such as ulcer, anemia, osteoporosis, and endocrine disruption. Increased attention is recently being focused on the examination of the analgesic potential of phytoconstituents, such as glycosides of traditional medicinal plants, because they often have suitable biological activities with fewer side effects as compared to synthetic drugs. The purpose of this article is to review for the first time the current state of knowledge on the use of glycosides from medicinal plants to induce analgesia and anti-inflammatory effect. Various databases and search engines, including PubMed, ScienceDirect, Scopus, Web of Science and Google Scholar, were used to search and collect relevant studies on glycosides with antinociceptive activities. The results led to the identification of several glycosides that exhibited marked inhibition of various pain mediators based on different well-established assays. Additionally, these glycosides were found to induce most of the analgesic effects through cyclooxygenase and lipoxygenase pathways. These findings can be useful to identify new candidates which can be clinically developed as analgesics with better bioavailability and reduced side effects. Graphical abstract Analgesic mechanisms of plant glycosides.

The Molecular Mechanisms Associated with the Effects of Propofol in a Rat Model of Pain Due to Inflammation Following Injection with Complete Freund's Adjuvant

Background

This study aimed to investigate the molecular mechanisms associated with the effects of propofol in a rat model of pain due to inflammation following subcutaneous injection with complete Freund’s adjuvant (CFA).

Material/Methods

Sprague-Dawley rats were injected subcutaneously in the paw with CFA. Propofol or saline was administered by tail vein injection. After CFA treatment for 0 hours, 4 hours, 1 day, 4 days, 7 days, and 14 days, the behavior of the rats was assessed. An enzyme-linked immunosorbent assay (ELISA) measured serum levels of proinflammatory cytokines, including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6. Western blot and the quantitative reverse-transcription polymerase chain reaction (qRT-PCR) were used to detect levels of p38MAPK and NF-κB related mRNA and proteins, including p-p38, p38, p65, p-p65, NOD-like receptor family protein 3 (NLRP3), apoptosis-associated speck-like protein (ASC) and caspase-1 in rat spinal cord tissues.

Results

Injection of CFA significantly reduced the mechanical withdrawal threshold (MWT), thermal withdrawal latency (TWL), and frequency responses to cold stimulation. Propofol treatment significantly reduced serum levels of TNF-α, IL-1β, and IL-6. Protein expression levels of p-p38 and p-p65 were upregulated in the rat model, which were inhibited by propofol treatment. CFA injection increased the expression levels of NLRP3, ASC, and caspase-1 in the spinal cord tissues of rats, which were reduced by propofol treatment.

Conclusions

In a rat model of pain following subcutanous injection with CFA, propofol reduced CFA-induced pain and inhibited the inflammatory response through the p38MAPK-nuclear factor-κB (NF-κB) pathway and the NLRP3 inflammasome.

In Vitro Anti-Inflammatory and In Vivo Antiarthritic Activities of Aqueous and Ethanolic Extracts of Dissotis thollonii Cogn. (Melastomataceae) in Rats

Dissotis thollonii Cogn. (Melastomataceae) is a tropical plant widely used in traditional Cameroonian medicine to relieve and treat many pathologies. It is widespread in the western region where it is used to treat typhoid fever, gastrointestinal disorders, and inflammatory diseases. The purpose of this study is to scientifically demonstrate the anti-inflammatory and antiarthritic properties of the aqueous and ethanolic extracts of the leaves of Dissotis thollonii. The anti-inflammatory properties were evaluated in vitro by inhibition tests for cyclooxygenase, 5-lipoxygenase, protein denaturation, extracellular ROS production, and cell proliferation; while antiarthritic properties were evaluated in vivo in rats using the zymosan A-induced monoarthritis test and the CFA-induced polyarthritis model. This study shows that aqueous and ethanolic extracts at a concentration of 1000 μg/ml inhibit the activity of cyclooxygenase (47.07% and 63.36%) and 5-lipoxygenase (66.79% and 77.7%) and protein denaturation (42.51% and 44.44%). Similarly, both extracts inhibited extracellular ROS production (IC₅₀ = 5.74 μg/ml and 2.96 μg/ml for polymorphonuclear leukocytes, 7.47 μg/ml and 3.28 μg ml for peritoneal macrophages of mouse) and cell proliferation (IC₅₀ = 16.89 μg/ml and 3.29 μg/ml). At a dose of 500 mg/kg, aqueous and ethanolic extracts significantly reduce edema induced by zymosan A (69.30% and 81.80%) and CFA (71.85% and 79.03%). At the same dose, both extracts decreased sensitivity to mechanical hyperalgesia with 69.00% and 70.35% inhibition, respectively. Systemic and histological analyzes show that both extracts maintain the studied parameters very close to normal and greatly restored the normal architecture of the joint in animals. Dissotis thollonii would therefore be a very promising source for the treatment of inflammatory diseases.

Anti-Inflammatory Properties of Plant Derived Natural Products - A Systematic Review

Traditionally, natural medicines have been administered as plant extracts, which are composed of a mixture of molecules. The individual molecular species in this mixture may or may not contribute to the overall medicinal effects and some may even oppose the beneficial activity of others. To better control therapeutic effects, studies that characterized specific molecules and describe their individual activity that have been performed over the past decades. These studies appear to underline that natural products are particularly effective as antioxidants and anti-inflammatory agents. In this systematic review we aimed to identify potent anti-inflammatory natural products and relate their efficacy to their chemical structure and physicochemical properties. To identify these compounds, we performed a comprehensive literature search to find those studies, in which a dose-response description and a positive control reference compound was used to benchmark the observed activity. Of the analyzed papers, 7% of initially selected studies met these requirements and were subjected to further analysis. This analysis revealed that most selected natural products indeed appeared to possess anti-inflammatory activities, in particular anti-oxidative properties. In addition, 14% of the natural products outperformed the remaining natural products in all tested assays and are attractive candidates as new anti-inflammatory agents.

Analgesic Effect of Zanthoxylum nitidum Extract in Inflammatory Pain Models Through Targeting of ERK and NF-κB Signaling

Background

Zanthoxylum nitidum (Roxb.) DC., also named Liang Mianzhen (LMZ), one kind of Chinese herb characterized with anti-inflammatory and relieving pain potency, which is widely used to treat injuries, rheumatism, arthralgia, stomach pain and so on in China. But its mechanism related to the anti-hyperalgesic has not been reported. The aim of this study was to investigate the analgesic activity of Liang Mianzhen on mice with Complete Freund adjuvant (CFA)-induced chronic inflammatory pain. Meanwhile, the peripheral and central mechanisms of analgesic effect of Liang Mianzhen were further examined via observing the effects of Liang Mianzhen on the signal pathway associated with inflammatory induced hyperalgesia.

Methods

The inflammatory pain model was established by intraplantar injection of CFA in C57BL/6J mice. After 1 day of CFA injection, the mice were treated with LMZ (100 mg/kg) for seven consecutive days, and the behavioral tests were measured after the daily intragastric administration of LMZ. The morphological changes on inflamed paw sections were determined by hematoxylin eosin (HE) staining. Changes in the mRNA expression levels of tumor necrosis factor (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β) and nuclear factor κB p65 (NF-κBp65) were measured on day seven after CFA injection by using real-time quantitative PCR analysis and enzyme linked immunosorbent assay (ELISA) method, respectively. Moreover, immunohistochemistry and western blotting were used to detect extracellular regulated protein kinases 1/2 (ERK1/2) and NF-κB signal pathway activation.

Results

The extract of LMZ (100 mg/kg) showed a significant anti-inflammatory and analgesic effect in the mice model. The paw edema volume was significantly reduced after the administration of LMZ compared to CFA group, as well as the paw tissues inflammatory damage was relived and the numbers of neutrophils in mice was reduced significantly. The CFA-induced mechanical threshold and thermal hyperalgesia value were significant improved with LMZ treatment at day three to day seven. We also found the mRNA levels of TNF-α, IL-1β, IL-6 and NF-κBp65 were down-regulate after 7 days from the LMZ treatment compared to CFA group. Meanwhile, LMZ significantly suppressed over-expression of the phosphorylation of ERK1/2 and NF-κBp65 in peripheral and central.

Conclusion

The present study suggests that the extract of LMZ attenuates CFA-induced inflammatory pain by suppressing the ERK1/2 and NF-κB signaling pathway at both peripheral and central level.

Salicylate and Procyanidin-Rich Stem Extracts of Gaultheria procumbens L. Inhibit Pro-Inflammatory Enzymes and Suppress Pro-Inflammatory and Pro-Oxidant Functions of Human Neutrophils Ex Vivo

Salicylate-rich plants are an attractive alternative to synthetic anti-inflammatory drugs due to a better safety profile and the advantage of complementary anti-inflammatory and antioxidant effects of the co-occurring non-salicylate phytochemicals. Here, the phytochemical value and biological effects in vitro and ex vivo of the stems of one of such plants, Gaultheria procumbens L., were evaluated. The best extrahent for effective recovery of the active stem molecules was established in comparative studies of five extracts. The UHPLC-PDA-ESI-MS³, HPLC-PDA, and UV-photometric assays revealed that the selected acetone extract (AE) accumulates a rich polyphenolic fraction (35 identified constituents; total content 427.2 mg/g dw), mainly flavanols (catechins and proanthocyanidins; 201.3 mg/g dw) and methyl salicylate glycosides (199.9 mg/g dw). The extract and its model components were effective cyclooxygenase-2, lipoxygenase, and hyaluronidase inhibitors; exhibited strong antioxidant capacity in six non-cellular in vitro models (AE and procyanidins); and also significantly and dose-dependently reduced the levels of reactive oxygen species (ROS), and the release of cytokines (IL-1β, IL-8, TNF-α) and proteinases (elastase-2, metalloproteinase-9) in human neutrophils stimulated ex vivo by lipopolysaccharide (LPS) and N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP). The cellular safety of AE was demonstrated by flow cytometry. The results support the application of the plant in traditional medicine and encourage the use of AE for development of new therapeutic agents.

Phytochemical analysis and anti-inflammatory effects of Filipendula vulgaris Moench extracts

Filipendula vulgaris Moench (dropwort) is used in traditional medicine for relieving various inflammation-related diseases. In the present study, the phytochemical profile of F. vulgaris aerial part (FVA) and root (FVR) methanolic extracts was evaluated by LC-DAD-HRMS analysis. Furthermore, their in vitro and in vivo anti-inflammatory effects, as well as their potential cytotoxicity, were assessed. Results showed that the extracts mainly contain phenolics like flavonoids, hydrolyzable tannins, procyanidins, and phenolic acid derivatives, including gaultherin. No in vitro cytotoxicity was found at the highest concentration (50 μg/mL). FVA extract (50 μg/mL) significantly inhibited cyclooxygenase-1 and -2 (COX-1 and COX-2) activities in vitro (>50% inhibition), and FVR extract considerably inhibited COX-2 activity (52.5 ± 2.7%) without affecting COX-2 gene expression in LPS-stimulated THP-1 cells. The extracts demonstrated prominent in vivo anti-inflammatory potential upon oral administration in rats. Especially FVA extract at 100 and 200 mg/kg significantly inhibited carrageenan-induced edema formation. From these results, it can be concluded that F. vulgaris extracts possess interesting anti-inflammatory properties.

Protective Effects of Sinomenine on CFA-Induced Inflammatory Pain in Rats

Background

The purpose of this study was to investigate the effects of sinomenine (SIN) on CFA-induced inflammatory pain in rats, and to explore the underlying molecular mechanisms.

Material/Methods

To determine the potential influences of SIN in the pathogenesis of inflammatory pain, an inflammatory pain (IP) mouse model was established and rats were treated with SIN (30 mg/kg). Behavioral tests were used to assess the MWT and TWL of the rats. ELISA assay was used to detect the level of inflammation cytokines. Western blotting and qRT-PCR were carried out to measure the related protein and mRNA expression level, respectively.

Results

We found that the MWT and TWL of the CFA-treated rats were markedly lower than that of the control rats, and they were significantly increased by SIN administration. The results suggest that IP rats had higher levels of TNF-α, IL-1β and IL-6 compared with the control rats. SIN administration decreased the levels of TNF-α, IL-1β, and IL-6. In addition, we found that p-p65 and p-p38 expression notably decreased after SIN treatment in IP rats. Moreover, the results showed that SIN inhibited Cox-2 and PGE2 expression in IP rats.

Conclusions

The data indicate that SIN had a protective role in inflammatory pain through repressing inflammatory mediators via preventing the p38MAPK-NF-κB pathway.

Gaultheria trichophylla (Royle): a source of minerals and biologically active molecules, its antioxidant and anti-lipoxygenase activities

BACKGROUND

Gaultheria trichophylla (Royle) is used as food and for treating many ailments in folk medicine especially against inflammation. The purpose of this in vitro study was to evaluate the ability of extracts of G. trichophylla as anti-oxidant and anti-inflammatory agent and for its mineral contents.

METHODS

Powdered plant material (100 g) was extracted with 100 ml each of methanol, chloroform, and n-hexane using soxhlet extractor. Antioxidant activity of methanol extract was assessed by DPPH radical scavenging and FRAP assays. Determination of enzyme inhibition activity was determined using 5-LOX inhibitory activity. Total phenolic and flavonoids contents were measured by Folin-Chicalteu and colorimeteric methods respectively. Minerals and heavy metals contents were determined using Atomic absorption spectrophotometer. Qualitative HPLC analysis were performed using some standard phenolic compounds.

RESULTS

The highest phenolic (17.5 ± 2.5 mg GA equivalent/g) and flavonoids (41.3 ± 0.1 mg QE equivalent/g) concentrations were found in methanol extract, which also showed more scavenging activity of 1, 1-diphenyl-2-picrylhydrazyl and ferrous reducing power with IC50 = 81.2 ± 0.2 and IC50 = 11.2 ± 0.1 μg/ml, respectively. The methanol and chloroform extracts showed best inhibition of 5-lipoxygenase enzyme with 90.5 ± 0.7% and 66.9 ± 0.1% at 0.5 mg/ml, respectively. G. trichophylla extract was also evaluated for mineral contents (K, Na, Ca, Mg, Fe, and Cu), and for chemical profiling of heavy metals (Cr, Pb, Cd, Co, Zn, Ni and Hg).

CONCLUSION

Our current findings suggest that this plant is good source of minerals and concentration of all heavy metals were within permissible limits. The results revealed that this ignored plant has great pharmaceutical and nutraceutical potential.

Gut modulatory and butyrylcholinesterase inhibitory activities of Gaultheria trichophylla

CONTEXT

Gaultheria trichophylla Royle (Ericaceae) and related species have been used in the traditional system of medicine for the treatment of diarrhoea, pain and inflammation.

OBJECTIVE

The present investigation explores G. trichophylla for its potential activity in hyperactive gut disorders.

MATERIALS AND METHODS

Antidiarrheal activity was evaluated on castor oil induced diarrhoea in mice with reference to standard drug verapamil. Gut modulatory activity was performed on isolated jejunum tissue preparations on spontaneous and high potassium induced contractions. Butyrylcholinesterase (BChE) inhibitory activity was performed with an in vitro study. Extract was tested for toxicity in mice.

RESULTS

In the in vivo studies, the methanol extract of G. trichophylla and verapamil significantly (p < 0.05, 0.01, 0.001) inhibited the frequency of defecation as well as wetting of faeces when compared with the negative control. The methanol (Gt. MeOH) extract of G. trichophylla caused a dose-dependent inhibitory effect on spontaneous contractions in isolated rabbit jejunum preparations and exhibited a partial inhibitory effect against high K⁺(80 mM) induced precontractions. Gt. MeOH shifted the Ca²⁺concentration-response curves (CRCs) to the right, suggesting calcium channel blocking like constituents. In an in vitro assay Gt. MeOH inhibited BChE enzyme with an IC₅₀ values of 35.52 ± 1.17 μg/mL. The extract showed no toxicity in mice at the dose of 3 g/kg.

DISCUSSION AND CONCLUSION

This study provides evidence that G. trichophylla possesses combinations of inhibitory and stimulatory effects mediated through possible cholinergic and less potent calcium blocking constituents, respectively. The latter may be responsible for the antidiarrheal effect.

Anti-inflammatory effect of a resveratrol derivative 3,4,5-trimethoxy-4',5'-dihydroxy-trans-stilbene (WL-09-5) via ROS-mediated NF-κB pathway

Inflammation derived from macrophages activation leads to various diseases. Synthetic modifications of resveratrol have been shown to have better anti-inflammatory activities. In this study, croton oil-induced mouse ear edema and lipopolysaccharides (LPS)-stimulated RAW264.7 macrophages were used to evaluate the anti-inflammatory effects of WL-09-5, a derivative of resveratrol. Furthermore, the activation of NF-κB was determined. Results showed that WL-09-5 significantly reduced the croton oil-induced ear edema, scavenged NO and ROS production, and reduced the levels of TNF-α, IL-6, and IL-1β. Furthermore, WL-09-5 may significantly inhibit the translocation of NF-κB in macrophage cells stimulated by LPS in a dose-dependent manner, which is a potent mechanism of its anti-inflammatory effects. In conclusion, WL-09-5 is an underlying candidate for inflammatory diseases that need further investigations.

Discovery and modelling studies of natural ingredients from Gaultheria yunnanensis (FRANCH.) against phosphodiesterase-4

Phosphodiesterase-4 (PDE4) is an anti-inflammatory target for treatment of asthma and chronic obstructive pulmonary disease (COPD). Here, we report the isolation and characterization of 13 compounds (G1-G13) by bioassay-guided fractionation of the ethyl acetate extraction of Gaultheria yunnanensis (FRANCH.), one of which pentacyclic triterpene (G1) has never been reported. Four of them (G1, G2, G4, and G5) inhibit PDE4 with the IC50 values < 20 μM and G1 is the most potent ingredient with an IC50 of 245 nM and moderate selectivity over other PDE families. Molecular dynamics simulations suggest that G1 forms a hydrogen bond with Asn362, in addition to the hydrogen bond with Gln369 and π-π interactions with Phe372, which are commonly observed in the binding of most PDE4 inhibitors. The calculated binding free energies for the interactions of PDE4-G1 and PDE4-G2 are -19.4 and -18.8 kcal/mol, in consistence with the bioassay that G1 and G2 have IC50 of 245 nM and 542 nM, respectively. The modelling results of these active compounds may aid the rational design of novel PDE4 inhibitors as anti-inflammatory agents.

Pharmacognostic standardization and preliminary phytochemical studies of Gaultheria trichophylla

CONTEXT

Gaultheria trichophylla Royle (Ericaceae) has long been used for various ailments in traditional systems of medicines; most importantly it is used against pain and inflammation.

AIMS

This study determines various pharmacognostic and phytochemical standards helpful to ensure the purity, safety, and efficacy of medicinal plant G. trichophylla.

MATERIAL AND METHODS

Intact aerial parts, powdered materials, and extracts were examined macro- and microscopically and pharmacognostic standardization parameters were determined in accordance with the guidelines given by the World Health Organization (WHO). Parameters including extractive values, ash values, and loss on drying were determined. Preliminary phytochemical tests, fluorescence analysis, and chromatographic profiling were performed for the identification and standardization of G. trichophylla.

RESULTS

The shape, size, color, odor, and surface characteristics were noted for intact drug and powdered drug material of G. trichophylla. Light and scanning electron microscope images of cross section of leaf and powdered microscopy revealed useful diagnostic features. Histochemical, phytochemical, physicochemical, and fluorescence analysis proved useful tools to differentiate the powdered drug material. High-performance liquid chromatography (HPLC) analysis showed the presence of important phytoconstituents such as gallic acid, rutin, and quercetin.

DISCUSSION AND CONCLUSIONS

The data generated from the present study help to authenticate the medicinally important plant G. trichophylla. Qualitative and quantitative microscopic features may be helpful for establishing the pharmacopeia standards. Morphology as well as various pharmacognostic aspects of different parts of the plant were studied and described along with phytochemical and physicochemical parameters, which could be helpful in further isolation and purification of medicinally important compounds.

Two novel lignans from Gaultheria yunnanensis

Two new lignans, 9-salicyl-(+)-isolariciresinol (1) and gaultheroside G (2), together with seven known compounds, were isolated from the ethanolic extract of the whole plant of Gaultheria yunnanensis. Their structures were determined by extensive NMR and MS analyses. Gaultheroside G (2) was found to have an unusual ether linkage between the 2 and 9' positions of aryl-tetralin lignan skeleton. All nine compounds were assayed for inhibitory effects against nitric oxide and pro-inflammatory cytokines TNF-α and IL-6 release in LPS-induced RAW 246.7 macrophages, while no significant activities were observed for the evaluated compounds.

Phytochemicals and Biological Activities of Poisonous Genera of Ericaceae in China

The family Ericaceae is comprised of about 70 genera of which about 20 are found throughout China. Of these Ledum, Rhododendron, Enkianthus, Pieris, Craibiodendron, Gaultheria, Vaccinium, and Leucothoe are regarded as poisonous. Many species of these poisonous genera are used as Chinese herbal medicines for the treatment of, for example, inflammation, asthma, and coughs. Modern research has demonstrated that the toxic ingredients of these poisonous genera are chiefly tetracyclic diterpenes, which have adverse effects on the digestive, cardiovascular and nervous systems. Because various species of these poisonous genera also have medicinal functions, extensive studies of these plants have led to the identification of many kinds of compound. This paper compiles 306 compounds from the eight poisonous genera, reported in 141 references.

The globalization of traditional medicine in northern peru: from shamanism to molecules

Northern Peru represents the center of the Andean "health axis," with roots going back to traditional practices of Cupisnique culture (1000 BC). For more than a decade of research, semistructured interviews were conducted with healers, collectors, and sellers of medicinal plants. In addition, bioassays were carried out to evaluate the efficacy and toxicity of plants found. Most of the 510 species encountered were native to Peru (83%). Fifty percent of the plants used in colonial times have disappeared from the pharmacopoeia. Market vendors specialized either on common and exotic plants, plants for common ailments, and plants only used by healers or on plants with magical purposes. Over 974 preparations with up to 29 different ingredients were used to treat 164 health conditions. Almost 65% of the medicinal plants were applied in these mixtures. Antibacterial activity was confirmed in most plants used for infections. Twenty-four percent of the aqueous extracts and 76% of the ethanolic extracts showed toxicity. Traditional preparation methods take this into account when choosing the appropriate solvent for the preparation of a remedy. The increasing demand for medicinal species did not increase the cultivation of medicinal plants. Most species are wild collected, causing doubts about the sustainability of trade.

Gaultheria: Phytochemical and pharmacological characteristics

The genus Gaultheria, comprised of approximately 134 species, is mostly used in ethnic drugs to cure rheumatism and relieve pain. Phytochemical investigations of the genus Gaultheria have revealed the presence of methyl salicylate derivatives, C₆-C₃ constituents, organic acids, terpenoids, steroids, and other compounds. Methyl salicylate glycoside is considered as a characteristic ingredient in this genus, whose anti-rheumatic effects may have a new mechanism of action. In this review, comprehensive information on the phytochemistry, volatile components and the pharmacology of the genus Gaultheria is provided to explore its potential and advance research.

Pharmacokinetics of methyl salicylate-2-O-β-D-lactoside, a novel salicylic acid analog isolated from Gaultheria yunnanensis, in dogs

Methyl salicylate-2-O-β-D-lactoside (MSL), a natural salicylate derivative of Gaultheria yunnanensis (Franch.) Rehder (G. yunnanensis), has been shown to provide a beneficial anti-inflammatory effect in animal models. Studies on the pharmacokinetics and bioavailability of MSL can provide both a substantial foundation for understanding its mechanism and empirical evidence to support its use in clinical practice. A simple and sensitive high-performance liquid chromatography (HPLC) method, coupled with ultraviolet analyte detection, was developed for determining the concentration of MSL and its metabolite in beagle plasma. Chromatographic separation was achieved on a Agilent Zorbax SB-C18 column (5 μM,4.6 × 250 mm). The mobile phase consisted of aqueous solution containing 0.1% phosphoric acid and acetonitrile (82:90, v/v), at a flow rate of 1 mL/min. Validation of the assay demonstrated that the developed HPLC method was sensitive, accurate and selective for the determination of MSL and its metabolite in dog plasma. After orally administering three doses of MSL, it could no longer be detected in dog plasma and its metabolite, salicylic acid, was detected. Salicylic acid showed a single peak in the plasma concentration-time curves and linear pharmacokinetics following the three oral doses (r(2) > 0.99). In contrast, only MSL was detected in plasma following intravenous administration. These results will aid in understanding the pharmacological significance of MSL. The developed method was successfully used for evaluation of the oral and intravenous pharmacokinetic profile of MSL in dogs.

Intervention of electroacupuncture on spinal p38 MAPK/ATF-2/VR-1 pathway in treating inflammatory pain induced by CFA in rats

Background

Previous studies have demonstrated that p38 MAPK signal transduction pathway plays an important role in the development and maintenance of inflammatory pain. Electroacupuncture (EA) can suppress the inflammatory pain. However, the relationship between EA effect and p38 MAPK signal transduction pathway in inflammatory pain remains poorly understood. It is our hypothesis that p38 MAPK/ATF-2/VR-1 and/or p38 MAPK/ATF-2/COX-2 signal transduction pathway should be activated by inflammatory pain in CFA-injected model. Meanwhile, EA may inhibit the activation of p38 MAPK signal transduction pathway. The present study aims to investigate that anti-inflammatory and analgesic effect of EA and its intervention on the p38 MAPK signal transduction pathway in a rat model of inflammatory pain.

Results

EA had a pronounced anti-inflammatory and analgesic effect on CFA-induced chronic inflammatory pain in rats. EA could quickly raise CFA-rat’s paw withdrawal thresholds (PWTs) and maintain good and long analgesic effect, while it subdued the ankle swelling of CFA rats only at postinjection day 14. EA could down-regulate the protein expressions of p-p38 MAPK and p-ATF-2, reduced the numbers of p-p38 MAPK-IR cells and p-ATF-2-IR cells in spinal dorsal horn in CFA rats, inhibited the expressions of both protein and mRNA of VR-1, but had no effect on the COX-2 mRNA expression.

Conclusions

The present study indicates that inhibiting the activation of spinal p38 MAPK/ATF-2/VR-1 pathway may be one of the main mechanisms via central signal transduction pathway in the process of anti-inflammatory pain by EA in CFA rats.

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.

Analgesic effect of electroacupuncture on inflammatory pain in collagen-induced arthritis rats: mediation by alpha2- and beta-adrenoceptors

This study was designed to investigate whether alpha- and beta-adrenergic systems mediate the analgesic effect of electroacupucture (EA) on inflammatory pain in a rat model of collagen-induced arthritis (CIA). To induce CIA, male Sprague-Dawley rats were immunized with bovine type II collagen emulsified in Freund's incomplete adjuvant, followed by a booster injection 14 days later. After induction of arthritis, the inflammatory pain threshold by the tail flick latency decreased as time passed and reached the minimum value at 4th week. Four weeks after the first immunization, low-frequency EA stimulation (2 Hz, 0.07 mA, 0.3 ms) delivered to Zusanli (ST(36)) for 30 min showed the analgesic effect. And also, the analgesic effect of EA was blocked by pretreatment with yohimbine (alpha2-adrenoceptor antagonist, 2 mg/kg, i.p.), but not by pretreatment with prazosin (alpha1-adrenoceptor antagonist, 1 mg/kg, i.p.) and propranolol (non-selective beta-adrenoceptor antagonist, 10 mg/kg, i.p.). These results suggest that the low-frequency EA can relieve the inflammatory pain in CIA, and the analgesic effect of EA can be mediated by alpha2- and beta-adrenoceptor, but not by alpha1-adrenoceptor.

Methyl salicylate 2-O-β-D-lactoside, a novel salicylic acid analogue, acts as an anti-inflammatory agent on microglia and astrocytes

BACKGROUND

Neuroinflammation has been known to play a critical role in the pathogenesis of Alzheimer's disease (AD). Activation of microglia and astrocytes is a characteristic of brain inflammation. Epidemiological studies have shown that long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) delays the onset of AD and suppresses its progression. Methyl salicylate-2-O-β-D-lactoside (DL0309) is a new molecule chemically related to salicylic acid. The present study aimed to evaluate the anti-inflammatory effects of DL0309.

FINDINGS

Our studies show that DL0309 significantly inhibits lipopolysaccharide (LPS)-induced release of the pro-inflammatory cytokines IL-6, IL-1β, and TNF-α; and the expression of the inflammation-related proteins iNOS, COX-1, and COX-2 by microglia and astrocytes. At a concentration of 10 μM, DL0309 prominently inhibited LPS-induced activation of NF-κB in glial cells by blocking phosphorylation of IKK and p65, and by blocking IκB degradation.

CONCLUSIONS

We demonstrate here for the first time that DL0309 exerts anti-inflammatory effects in glial cells by suppressing different pro-inflammatory cytokines and iNOS/NO. Furthermore, it also regulates the NF-κB signaling pathway by blocking IKK and p65 activation and IκB degradation. DL0309 also acts as a non-selective COX inhibitor in glial cells. These studies suggest that DL0309 may be effective in the treatment of neuroinflammatory disorders, including AD.

Anti-inflammatory activity of methyl salicylate glycosides isolated from Gaultheria yunnanensis (Franch.) Rehder

Gaultheria yunnanensis (Franch.) Rehder is a kind of traditional Chinese herbal medicine used for the treatments of rheumatoid arthritis, swelling and pain. Two methyl salicylate glycosides, namely methyl benzoate-2-O-β-D-xylopyranosyl(1-6)-O-β-D-gluco-pyranoside (J12122) and methyl benzoate-2-O-β-D-xylopyranosyl(1-2)[O-β-D-xylopyranosyl(1-6)]-O-β-D-glucopyranoside (J12123), are natural salicylic derivatives isolated from Gaultheria yunnanensis. In this study, we investigated the anti-inflammatory activity of J12122 and J12123 on LPS-induced RAW264.7 macrophage cells by measuring the production of pro-inflammatory cytokines, accumulation of nitric oxide (NO), and level of reactive oxygen species (ROS). The results showed that both methyl salicylate glycosides dose-dependently inhibited the production of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and IL-6, respectively. Consistent with these observations, J12122 and J12123 significantly suppressed the accumulation of NO, with an inhibitory rate of 56.20% and 51.72% at 3.0 μg/mL concentration, respectively. Furthermore, the two methyl salicylate glycosides reduced the level of ROS induced by LPS. These results showed that the isolated compounds possess anti-inflammatory properties through inhibition the production pro-inflammatory cytokines, NO, and ROS.

Anti-inflammatory and anti-nociceptive effect of Betula platyphylla var. japonica in human interleukin-1β-stimulated fibroblast-like synoviocytes and in experimental animal models

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional medicine has widely been used Betula platyphylla var. japonica to treat various inflammatory diseases including arthritis.

AIM OF THE STUDY

To determine the anti-inflammatory, anti-nociceptive, and anti-arthritic effects of Betula platyphylla in interleukin-1β (IL-1β)-stimulated fibroblast-like synoviocytes from human rheumatoid arthritis and in nociceptive and inflammatory animal model.

MATERIALS AND METHODS

The inflammatory mediators such as IL-6, tumor necrosis factor (TNF)-α matrix metalloproteinase (MMP)-1, MMP-13, inducible nitric oxide synthesis (iNOS), nitrites, prostaglandin E(2) (PGE(2)) and cyclo-oxygenase 2 (COX-2) activity of Betula platyphylla were tested in IL-1β-stimulated fibroblast-like synoviocytes. Tail withdrawal in response to thermal stimulation in tail flick test or paw flinching and shaking in response to sc hind paw formalin injection was measured 1h after oral administration of Betula platyphylla. The former was evaluated with a paw pressure test, and the latter was measured using the squeaking score, and paw volume in inflammatory arthritis tests.

RESULTS

Betula platyphylla significantly inhibited proliferation of IL-1β-induced synoviocytes. Betula platyphylla reduced the levels of inflammatory mediators, such as IL-6, TNF-α, MMP-1, MMP13, and PGE(2). In particular, Betula platyphylla significantly inhibited the releases of nitrites and iNOS, as well as release of NFκB, into the nucleus of IL-1β-treated synoviocytes, even at concentrations as low as 1μg/ml. Oral administrant of Betula platyphylla at 400mg/kg significantly decreased about 27.8% of tail flick withdrawal and inhibited about the number of paw flinches in both phases 1 and 2 of the formalin test. In the carrageenan-induced acute pain and arthritis model, Betula platyphylla dose dependently reduced the nociceptive threshold and the arthritic symptoms at day 8, respectively, and Betula platyphylla at 400mg/kg markedly reduced the inflammatory area about 48% in the ankle joints. This capacity of Betula platyphylla at 400mg/kg was similar to that of the celecoxib-2 inhibitor in carrageenan-induced nociceptive and inflammatory arthritis model.

CONCLUSIONS

These results suggest that Betula platyphylla has anti-nociceptive and anti-inflammatory effects in IL-1β-stimulated RA FLS and in an animal model of arthritis. Thus, the use of Betula platyphylla as a pharmaceutical candidate for the treatment of arthritis should be further studied.

Anti-inflammatory and antiarthritic effects of piperine in human interleukin 1beta-stimulated fibroblast-like synoviocytes and in rat arthritis models

Introduction

The objective of this study was to determine the anti-inflammatory, nociceptive, and antiarthritic effects of piperine, the active phenolic component in black pepper extract.

Methods

The in vitro anti-inflammatory activity of piperine was tested on interleukin 1β (IL1β)-stimulated fibroblast-like synoviocytes derived form patients with rheumatoid arthritis. The levels of IL6, matrix metalloproteinase (MMPs), cyclo-oxygenase 2 (COX-2), and prostaglandin E2 (PGE₂) were investigated by ELISA and RT-PCR analysis. The analgesic and antiarthritic activities of piperine were investigated on rat models of carrageenan-induced acute paw pain and arthritis. The former were evaluated with a paw pressure test, and the latter by measuring the squeaking score, paw volume, and weight distribution ratio. Piperine was administrated orally to rats at 20 and 100 mg/kg/day for 8 days.

Results

Piperine inhibited the expression of IL6 and MMP13 and reduced the production of PGE₂ in a dose dependant manner at concentrations of 10 to 100 μg/ml. In particular, the production of PGE₂ was significantly inhibited even at 10 μg/ml of piperine. Piperine inhibited the migration of activator protein 1 (AP-1), but not nuclear factor (NF)κB, into the nucleus in IL1β-treated synoviocytes. In rats, piperine significantly reduced nociceptive and arthritic symptoms at days 8 and 4, respectively. Histological staining showed that piperine significantly reduced the inflammatory area in the ankle joints.

Conclusions

These results suggest that piperine has anti-inflammatory, antinociceptive, and antiarthritic effects in an arthritis animal model. Thus, piperine should be further studied with regard to use either as a pharmaceutical or as a dietary supplement for the treatment of arthritis.

Bioassay-guided isolation of an anti-ulcer diterpenoid from Croton reflexifolius: role of nitric oxide, prostaglandins and sulfhydryls

Croton reflexifolius H. B. K (Euphorbiaceae) is a very common medicinal plant in the Huastecan region of Mexico that, according to local folk medicine, is considered useful in the treatment of gastritis and gastric ulcer. We have aimed to test the validity of this practice by using the experimental model of an ethanol-induced gastric ulcer in male Wistar rats. The results showed that C. reflexifolius had gastroprotector activity, that the hexane extract had the highest protective activity (64.38+/-7.72%), and that polyalthic acid isolated from this extract was the main active gastroprotector agent. Rats treated orally with polyalthic acid showed a gastroprotective effect similar to that elicited by carbenoxolone. As with carbenoxolone, the effect elicited by polyalthic acid was attenuated by pretreatment with either N(G)-nitro-L-arginine methyl ester (70 mgkg(-1), i.p.), a nitric oxide (NO) synthase inhibitor, or N-ethylmaleimide (10 mgkg(-1), s.c.), a blocker of sulfhydryl groups. This suggested that the gastroprotective mechanism of this diterpenoid involved the participation of both NO and endogenous sulfhydryl groups. Contrary to carbenoxolone, the gastroprotective effect of polyalthic acid was not affected by the inhibition of prostaglandin synthesis with indometacin (10 mgkg(-1), s. c.). In conclusion, Croton reflexifolius contains compounds with gastroprotector activity. Polyalthic acid, which was isolated from this plant, was the main compound with gastroprotector activity, having effectiveness similar to that found with the use of carbenoxolone. Whereas NO and sulfhydryl groups were involved in the mechanisms of gastroprotective action of polyalthic acid, prostaglandins were not.

Enhancement of anti-inflammatory property of aspirin in mice by a nano-emulsion preparation

Aspirin, a non-steroidal anti-inflammatory drug, widely used for its anti-inflammatory properties is associated with several systemic side effects including gastro-intestinal discomfort. Inflammation can be mediated by pro-inflammatory cytokines and, along with various other host factors eventually give rise to edema at the inflamed site. Because of the adverse side effects oftentimes associated with systemic exposure to aspirin, the aim of the present study was to investigate whether the anti-inflammatory property of aspirin would enhance if delivered as nano-emulsion preparation. Nano-emulsion preparations of aspirin prepared with a Microfluidizer Processor were evaluated in the croton-oil-induced ear edema CD-1 mouse model using ear lobe thickness and the accumulation of specific in situ cytokines as biomarkers of inflammation. The results showed that particle size (90 nm) populations of nano-emulsion preparations of aspirin compared to an aspirin suspension (363 nm), significantly decreased (p<0. 05) ear lobe thickness approximately 2 fold greater than the aspirin suspension. In addition, the aspirin nano-emulsion further reduced the auricular levels of IL-1alpha (-37%) and TNFalpha (-69%) compared to the aspirin suspension preparation (p<0.05). The reductions in ear lobe thickness were also significantly associated with accumulated tissue levels of IL-1alpha (r=0.5, p<0.009) and TNFalpha (r=0.7, p<0.0004), respectively. In conclusion, these studies indicate that a nano-emulsion preparation of aspirin significantly improved the anti-inflammatory properties of an aspirin suspension in a CD-1 mouse model of induced inflammation.