Effect of oleanolic acid on complement in adjuvant- and carrageenan-induced inflammation in rats

Halorotetin A: A Novel Terpenoid Compound Isolated from Ascidian Halocynthia rotetzi Exhibits the Inhibition Activity on Tumor Cell Proliferation

Halocynthia roretzi, the edible ascidian, has been demonstrated to be an important source of bioactive natural metabolites. Here, we reported a novel terpenoid compound named Halorotetin A that was isolated from tunic ethanol extract of H. roretzi by silica gel column chromatography, preparative layer chromatography (PLC), and semipreparative-HPLC. 1H and 13C NMRs, 1H-1H COSY, HSQC, HMBC, NOESY, and HRESIMS profiles revealed that Halorotetin A was a novel terpenoid compound with antitumor potentials. We therefore treated the culture cells with Halorotetin A and found that it significantly inhibited the proliferation of a series of tumor cells by exerting cytotoxicity, especially for the liver carcinoma cell line (HepG-2 cells). Further studies revealed that Halorotetin A affected the expression of several genes associated with the development of hepatocellular carcinoma (HCC), including oncogenes (c-myc and c-met) and HCC suppressor genes (TP53 and KEAP1). In addition, we compared the cytotoxicities of Halorotetin A and doxorubicin on HepG-2 cells. To our surprise, the cytotoxicities of Halorotetin A and doxorubicin on HepG-2 cells were similar at the same concentration and Halorotetin A did not significantly reduce the viability of the normal cells. Thus, our study identified a novel compound that significantly inhibited the proliferation of tumor cells, which provided the basis for the discovery of leading compounds for antitumor drugs.

Advances in Anti-inflammatory Activity, Mechanism and Therapeutic Application of Ursolic Acid

In vivo and in vitro studies reveal that Ursolic Acid (UA) is able to counteract endogenous and exogenous inflammatory stimuli and has favorable anti-inflammatory effects. The antiinflammatory mechanisms mainly include decreasing the release of histamine in mast cells, suppressing the activities of lipoxygenase, cyclooxygenase and phospholipase, and reducing the production of nitric oxide and reactive oxygen species, blocking the activation of the signal pathway, downregulating the expression of inflammatory factors, and inhibiting the activities of elastase and complement. These mechanisms can open up new avenues for the scientific community to develop or improve novel therapeutic approaches to tackle inflammatory diseases, such as arthritis, atherosclerosis, neuroinflammation, liver diseases, kidney diseases, diabetes, dermatitis, bowel diseases, cancer. The anti-inflammatory activity, the anti-inflammatory mechanism of ursolic acid and its therapeutic applications are reviewed in this paper.

Development and Evaluation of Oleanolic Acid Dosage Forms and Its Derivatives

Oleanolic acid is a pentacyclic triterpenoid compound that exists widely in medicinal herbs and other plants. Because of the extensive pharmacological activity, oleanolic acid has attracted more and more attention. However, the structural characteristics of oleanolic acid prevent it from being directly made into new drugs, which limits the application of oleanolic acid. Through the application of modern preparation techniques and methods, different oleanolic acid dosage forms and derivatives have been designed and synthesized. These techniques can improve the water solubility and bioavailability of oleanolic acid and lay a foundation for the new drug development. In this review, the recent progress in understanding the oleanolic acid dosage forms and its derivatives are discussed. Furthermore, these products were evaluated comprehensively from the perspective of characterization and pharmacokinetics, and this work may provide ideas and references for the development of oleanolic acid preparations.

Peripheral Anti-nociceptive and Anti-inflammatory Effect of Oleanolic Acid in a Rat Model of Osteoarthritis

BACKGROUND

Oleanolic acid (OA) is a naturally occurring pentacyclic triterpenoid with multifarious actions. Chief among them is the anti-inflammatory effect it exerts when taken orally; however, the underpinning mechanisms of such effects have not yet been fully explored.

METHODS

In the present study, we evaluated the anti-inflammatory and anti-nociceptive effect of OA by injecting it directly into the knee joint using an animal model of osteoarthritis. Behavioral and electrophysiological studies were conducted to determine whether OA exerts a direct modulatory effect on primary sensory afferents that could lead to a decrease in pain-related behaviors and inflammatory responses. Rats were divided into two main groups: a pre- and a post-treatment group. Knee joint inflammation was induced by injecting a mixture of 3% kaolin and carrageenan (K/C). In the pre-treatment groups, two different doses of OA [5 mg/ml (n=5) and 30 mg/ml (n=4); 0.1 ml per injection] were administered into the synovial cavity of the knee joint before induction of inflammation. In the post-treatment group, rats received only one dose [5 mg/ml (n=5)] of OA after induction of inflammation.

RESULTS

Results indicate that intra-articular injection of OA improves motor coordination and attenuates nociceptive behav-ior and inflammatory reactions. More importantly, we observed a direct depolarizing action of OA on articular sensory fi-bers, a crucial mechanism that activates descending inhibitory pathways and controls incoming nociceptive signals to the spinal cord.

CONCLUSION

Overall, our findings suggest that OA can be used as preventive and therapeutic approach for the management of osteoarthritis.

The Inhibitory Effects of Pentacyclic Triterpenes from Loquat Leaf against Th17 Differentiation

BACKGROUND

Loquat leaf is an herb that is commonly used in traditional Chinese medicine (TCM) for its anti-inflammatory properties. Numerous studies have demonstrated that Th17 cells play a fundamental role in mediating SLE pathological deterioration. In our study, we investigated the inhibitory effect of pentacyclic triterpenes from loquat leaf on T helper 17 (Th17) cells and the therapeutic efficacy of OA in Lupus nephritis (LN) development.

METHODS

We isolated three pentacyclic triterpene compounds rom loquat leaf by bioassay-directed fractionation and separation method. There were methyl corosolate (MC), uvaol (UL), and oleanolic acid (OA) Firstly, we elucidated Retinoic acid receptor-related orphan receptor gamma t (RORγt) inhibitory activity of these three compounds in the cell-based assay and Th17 differentiation in vitro assay. Then, we used OA-treated pristine-induced LN mice to evaluate the therapeutic effects of OA in LN development. Anti-dsDNA level in serum was detected by enzyme-linked immunosorbent assay (ELISA), interleukin 17A (IL-17A) and interferon-γ (IFN-γ) expression in spleen cells by Flow cytometry (FCM), histomorphologic examination of kidneys were performed by periodic acid schiff (PAS) staining and immunofluorescence analysis.

RESULTS

Pentacyclic triterpene compounds (MC, UL, OA) displayed inhibition of RORγt activity in cell-based assay and Th17 differentiation in vitro. Furthermore, our results also showed that OA could significantly decrease serum anti-dsDNA antibody levels, IL-17A and IFN-γ expression and alleviate renal pathological damage in OA-treated group mice than in the model group mice.

CONCLUSION

These results demonstrated that OA can improve the clinical manifestation of LN, indicating potential application in SLE therapy.

Spectrum-Effect Relationships between Fingerprints of Caulophyllum robustum Maxim and Inhabited Pro-Inflammation Cytokine Effects

Caulophyllum robustum Maxim (CRM) is a Chinese folk medicine with significant effect on treatment of rheumatoid arthritis (RA). This study was designed to explore the spectrum-effect relationships between high-performance liquid chromatography (HPLC) fingerprints and the anti-inflammatory effects of CRM. Seventeen common peaks were detected by fingerprint similarity evaluation software. Among them, 15 peaks were identified by Liquid Chromatography-Mass Spectrometry (LC-MS). Pharmacodynamics experiments were conducted in collagen-induced arthritis (CIA) mice to obtain the anti-inflammatory effects of different batches of CRM with four pro-inflammation cytokines (TNF-α, IL-β, IL-6, and IL-17) as indicators. These cytokines were suppressed at different levels according to the different batches of CRM treatment. The spectrum-effect relationships between chemical fingerprints and the pro-inflammation effects of CRM were established by multiple linear regression (MLR) and gray relational analysis (GRA). The spectrum-effect relationships revealed that the alkaloids (N-methylcytisine, magnoflorine), saponins (leiyemudanoside C, leiyemudanoside D, leiyemudanoside G, leiyemudanoside B, cauloside H, leonticin D, cauloside G, cauloside D, cauloside B, cauloside C, and cauloside A), sapogenins (oleanolic acid), β-sitosterols, and unknown compounds (X3, X17) together showed anti-inflammatory efficacy. The results also showed that the correlation between saponins and inflammatory factors was significantly closer than that of alkaloids, and saponins linked with less sugar may have higher inhibition effect on pro-inflammatory cytokines in CIA mice. This work provided a general model of the combination of HPLC and anti-inflammatory effects to study the spectrum-effect relationships of CRM, which can be used to discover the active substance and to control the quality of this treatment.

Polymeric nanoparticles developed by vitamin E-modified aliphatic polycarbonate polymer to promote oral absorption of oleanolic acid

Oleanolic acid (OA) exhibited good pharmacological activities in the clinical treatment of hypoglycemia, immune regulation, acute jaundice and chronic toxic hepatitis. However, the oral delivery of OA is greatly limited by its inferior water solubility and poor intestinal mucosa permeability. Herein, we developed a novel polymeric nanoparticle (NP) delivery system based on vitamin E modified aliphatic polycarbonate (mPEG-PCC-VE) to facilitate oral absorption of OA. OA encapsulated mPEG-PCC-VE NPs (OA/mPEG-PCC-VE NPs) showed uniform particle size of about 170 nm with high drug loading capability (8.9%). Furthermore, the polymeric mPEG-PCC-VE NPs, with good colloidal stability and pH-sensitive drug release characteristics, significantly enhanced the in vitro dissolution of OA in the alkaline medium. The in situ single pass intestinal perfusion (SPIP) studies performed on rats demonstrated that the OA/mPEG-PCC-VE NPs showed significantly improved permeability in the whole intestinal tract when compared to OA solution, especially for duodenum and colon. As a result, the in vivo pharmacokinetics study indicated that the bioavailability of OA/mPEG-PCC-VE NPs showed 1.5-fold higher than commercially available OA tablets. These results suggest that mPEG-PCC-VE NPs are a promising platform to facilitate the oral delivery of OA.

Oleanolic acid acetate inhibits rheumatoid arthritis by modulating T cell immune responses and matrix-degrading enzymes

Rheumatoid arthritis (RA) is a chronic autoimmune disease associated with a combination of synovium joint inflammation, synovium hyperplasia, and destruction of cartilage and bone. Oleanolic acid acetate (OAA), a compound isolated from Vigna angularis, has been known to possess pharmacological activities, including anti-inflammation and anti-bone destruction. In this study, we investigated the effects of OAA on RA and the underlying mechanisms of action by using a type-II collagen-induced arthritis (CIA) mouse model and tumor necrosis factor (TNF)-α-stimulated RA synovial fibroblasts. Oral administration of OAA decreased the clinical arthritis symptoms, paw thickness, histologic and radiologic changes, and serum total and anti-type II collagen IgG, IgG1, and IgG2a levels. OAA administration reduced Th1/Th17 phenotype CD4(+) T lymphocyte expansions and inflammatory cytokine productions in T cell activated draining lymph nodes and spleen. OAA reduced the expression and production of inflammatory mediators, such as cytokines and matrix metalloproteinase (MMP)-1/3, in the ankle joint tissue and RA synovial fibroblasts by down-regulating Akt, mitogen-activated protein kinases, and nuclear factor-κB. Our results clearly support that OAA plays a therapeutic role in RA pathogenesis by modulating helper T cell immune responses and matrix-degrading enzymes. The immunosuppressive effects of OAA were comparable to dexamethasone and ketoprofen. We provide evidences that OAA could be a potential therapeutic candidate for RA.

Oleanolic acid acrylate elicits antidepressant-like effect mediated by 5-HT1A receptor

The development of new drugs for the treatment of depression is strategic to achieving clinical needs of patients. This study evaluates antidepressant-like effect and neural mechanisms of four oleanolic acid derivatives i.e. acrylate (D1), methacrylate (D2), methyl fumarate (D3) and ethyl fumarate (D4). All derivatives were obtained by simple one-step esterification of oleanolic acid prior to pharmacological screening in the forced swimming (FS) and open field (OF) tests. Pharmacological tools like α-methyl-p-tyrosine (AMPT, catecholamine depletor), p-chlorophenylalanine (serotonin depletor), prazosin (PRAZ, selective α1-receptor antagonist), WAY-100635 (selective serotonin 5-HT_1A receptor antagonist) as well as monoamine oxidase (MAO) and functional binding assays were conducted to investigate possible neural mechanisms. In the FS test, D1 showed the most promising antidepressant-like effect without eliciting locomotor incoordination. Unlike group of mice pretreated with AMPT 100 mg/kg, PCPA 100 mg/kg or PRAZ 1 mg/kg, the effect of D1 was attenuated by WAY-100635 0.3 mg/kg pretreatment. D1 demonstrated moderate inhibition of MAO-A (IC₅₀ = 48.848 ± 1.935 μM), potency (pEC₅₀ = 6.1 ± 0.1) and intrinsic activity (E_max = 26 ± 2.0%) on 5-HT_1A receptor. In conclusion, our findings showed antidepressant-like effect of D1 and possible involvement of 5-HT_1A receptor.

Chaenomeles speciosa: A review of chemistry and pharmacology

Chaenomeles speciosa (Sweet) Nakai (C. speciosa, Rosaceae family) is an effective medicinal plant, which has long been used in China to treat various diseases, such as rheumatism, cholera, dysentery, enteritis, beriberi and vitamin C deficiency syndrome. A series of chemical constituents, including triterpenoid, phenolic and phenylpropionic acids, flavonoids, saccharides, essential oils and alkaloids, have been isolated from this plant and some have already been evaluated for their biological activities. Pharmacological investigations demonstrated that C. speciosa possesses anti-inflammatory, antinociceptive, antimicrobial, antioxidant, immunoregulatory, antiparkinsonian, hepatoprotective and antitumor properties. The objective of this review was to summarise available up-to-date and comprehensive information on C. speciosa and provide a relevant reference for further investigations.

Bioactive properties of the main triterpenes found in olives, virgin olive oil, and leaves of Olea europaea

Oleanolic acid, maslinic acid, uvaol, and erythrodiol are the main triterpenes present in olives, olive tree leaves, and virgin olive oil. Their concentration in virgin olive oil depends on the quality of the olive oil and the variety of the olive tree. These triterpenes are described to present different properties, such as antitumoral activity, cardioprotective activity, anti-inflammatory activity, and antioxidant protection. Olive oil triterpenes are a natural source of antioxidants that could be useful compounds for the prevention of multiple diseases related to cell oxidative damage. However, special attention has to be paid to the concentrations used, because higher concentration may lead to cytotoxic or biphasic effects. This work explores all of the bioactive properties so far described for the main triterpenes present in virgin olive oil.

Inhibition of tumor progression by naturally occurring terpenoids

CONTEXT

Cancer is a major public health problem in India and many other parts of the world. Its two main characteristics are uncontrolled cell growth and metastasis. Natural products represent a rich source of compounds that have found many applications in various fields of medicines and therapy including cancer therapy. Effective ingredients in several plant-derived medicinal extracts are terpenoid compounds and many terpenes have biological activities and are used for the treatment of human diseases.

OBJECTIVES

This review attempted to collect all available published scientific literature of eight naturally occurring terpenoids and their effect on inhibition of tumor progression.

METHODS

The present review is about eight potent naturally occurring terpenoids that have been studied for their pharmacological properties in our lab and this review includes 130 references compiled from all major databases.

RESULTS

Literature survey revealed that triterpenoids, such as glycyrrhizic acid, ursolic acid, oleanolic acid, and nomilin, the diterpene andrographolide, and the monoterpenoids like limonene and perillic acid had shown immunomodulatory and antitumor activities. All of them could induce apoptosis in various cancer cells by activating various proapoptotic signaling cascades. Many of these terpenoids found to inhibit metastatic progression and tumor-induced angiogenesis. The molecular mechanisms that involved in these activities include inhibition of various oncogenic and anti-apoptotic signaling pathways and suppression or nuclear translocation of various transcription factors including nuclear factor kappa B (NF-κB).

CONCLUSION

The chemopreventive and chemoprotective effects of these compounds point toward their possible role in modern anticancer therapies.

Suppression of COX-2, IL-1β and TNF-α expression and leukocyte infiltration in inflamed skin by bioactive compounds from Rosmarinus officinalis L

In the present study, we evaluated the effects of extracts and purified compounds from fresh leaves of Rosmarinus officinalis L. Pretreatment with the major anti-inflammatory compounds, carnosic acid (CA) and carnosol (CS), inhibited phorbol 12-myristate 13-acetate (PMA)-induced ear inflammation in mice with an EC(50) of 10.20 μg/cm(2) and 10.70 μg/cm(2), respectively. To further understand the anti-inflammatory mechanism of these compounds, we analyzed the in vivo expression of several inflammation-associated genes in mouse skin by reverse transcriptase-polymerase chain reaction (RT-PCR). Our data showed that CA and CS reduced the expression of IL-1β and TNF-α but had less effect on fibronectin and ICAM-1 expression. Interestingly, both compounds selectively inhibited COX-2 but not COX-1. Histopathological analysis of hematoxylin and eosin (H&E)-stained tissue revealed a marked reduction in leukocyte infiltration and epidermal ulceration of PMA-treated ears when ears were pretreated with ethanolic extracts or pure CA. In vitro, we showed that ethanolic extract, carnosic acid and carnosol significantly inhibited the overproduction of nitric oxide (NO) in a dose-dependent manner in the RAW 264.7 murine macrophage cell line. For the first time in vivo, we showed that CA and CS differentially regulate the expression of inflammation-associated genes, thus demonstrating the pharmacological basis for the anti-inflammatory properties reported for CA and CS.

Synthesis of 3H-spiro[benzofuran-2,1′-cyclohexane] derivatives from naturally occurring filifolinol and their classical complement pathway inhibitory activity

Six 3H-spiro[benzofuran-2,1'-cyclohexane] derivatives were synthesized from naturally occurring filifolinol, and their classical complement pathway inhibitory activity was determined. IC(50) values of the most potent compounds were comparable to the activity of the natural complement inhibitor K76-COOH and some synthetic tricyclic analogs of it.

Oleanolic acid inhibits the activity of the multidrug resistance protein ABCC1 (MRP1) but not of the ABCB1 (P-glycoprotein): possible use in cancer chemotherapy

The effects of oleanolic acid (OA) on ABCB1 and ABCC1 activities were studied in a cell line constitutively expressing both proteins. It was observed that OA did not alter ABCB1 activity, but inhibited the activity of ABCC1 protein. This inhibition was reversible and only occurred in the presence of OA. In addition, OA did not alter the expression of ABCC1 mRNA. These results suggest that OA could be a good choice in the treatment of MDR tumours, either as a chemotherapic itself in tumours bearing ABCB1, or as an adjuvant in the chemotherapy of ABCC1 expressing tumours.

Oleanolic Acid, a pentacyclic triterpene attenuates the mustard oil-induced colonic nociception in mice

Many natural terpenoid compounds from plants exhibit antinociceptive property but very few studies have addressed their efficacy in visceral models of nociception. The present study evaluated the antinociceptive potential of oleanolic acid, a pentacyclic triterpene in the mouse model of colonic nociception induced by mustard oil. We further examined the possible participation of opioid, alpha2-adrenergic, and transient receptor potential vanilloid 1 (TRPV1)-receptors in its mechanism. Mice were pretreated orally with oleanolic acid (3, 10, 30 mg/kg) or vehicle, and the pain-related behavioral responses to intracolonic injection of mustard oil was analysed. Oleanolic acid significantly suppressed the mustard oil-induced nociceptive behaviors at test doses of 10 and 30 mg/kg, in a dose-related manner. The antinociceptive effect of oleanolic acid (30 mg/kg) was significantly blocked by pretreatment with the opioid antagonist, naloxone (2 mg/kg, i.p.), while the alpha2-adrenoceptor antagonist, yohimbine (2 mg/kg, s.c.), had no effect. Pretreatment with ruthenium red (3 mg/kg, s.c.), a non-competitive TRPV1 antagonist alone caused significant inhibition of mustard oil-induced nociception but its co-administration with oleanolic acid produced neither antagonism nor potentiation of oleanolic acid antinociception. In the open-field test that detects sedative or motor abnormality, mice received 30 mg/kg oleanolic acid did not show any per se influence, but significantly inhibited the mustard oil-induced decrease in ambulation frequency. These data demonstrate the visceral antinociceptive potential of oleanolic acid that involves an opioid mechanism and possibly a modulatory influence on vanilloid-receptors, which needs further study.

Anti-complementary activity of triterpenoides from fruits of Zizyphus jujuba

In order to determine on the anti-complement activity of triterpenes, following eleven triterpenoides were isolated from the fruits of the Zizyphus jujuba MILL: ceanothane-type triterpenes: colubrinic acid (1), zizyberenalic acid (11); lupane-type triterpenes: alphitolic acid (2), 3-O-cis-p-coumaroyl alphitolic acid (3), 3-O-trans-p-coumaroyl alphitolic acid (4), betulinic acid (7), betulonic acid (9); and oleanane-type triterpenes: 3-O-cis-p-coumaroyl maslinic acid (5), 3-O-trans-p-coumaroyl maslinic acid (6), oleanolic acid (8), oleanonic acid (10). These compounds were examined for their anti-complement activity against the classical pathway of the complement system. Among them, compounds 5, 6, and 8 exhibited significant anti-complement activity with IC(50) values of 101.4, 143.9, and 163.4 microM, respectively, whereas the ceanothane-type and the lupane-type triterpenes were inactive. This suggests that the oleanane-structure plays an important role in inhibiting the hemolytic activity of human serum against erythrocytes.

Extracts and constituents of Lavandula multifida with topical anti-inflammatory activity

The topical anti-inflammatory activity of the ethanol and aqueous extracts from the aerial parts of Lavandula multifida L. (Lamiaceae), used in the Moroccan traditional medicine, was investigated by inhibition of the Croton oil-induced ear edema in mice. The biological assay revealed a dose-dependent anti-inflammatory activity for the ethanol extract, while the aqueous one was less active. Bioassay-guided fractionation of the ethanol extract led to identify four triterpenic acids of oleanane series, four pimarane and one iso-pimarane diterpenes, as well as the phenolic monoterpene carvacrol and its glucoside. Some of these compounds revealed an anti-inflammatory activity comparable to that of indomethacin.

In vivo topical anti-inflammatory and in vitro antioxidant activities of two extracts of Thymus satureioides leaves

Four extracts at increasing polarity were prepared from the leaves of Thymus satureioides Coss. (Labiatae) and assayed for the in vivo topical anti-inflammatory effect using the croton oil ear test in mice, and for in vitro both antioxidant (DPPH degrees test) and anti-bacterial (broth microdilution method) activities. The chloroform extract showed a topical anti-inflammatory activity (ID50=282 microg cm(-2)), only three times lower than that of the reference drug indomethacin (ID50=93 microg cm(-2)) and its active components were identified as ursolic and oleanolic acids. The methanol extract, showing a significant radical-scavenging effect (SC50=14.54 microg), was characterized by the isolation and identification of some flavonoids. On the contrary, the extracts did not show any anti-bacterial effect against four standard aerobial bacteria strains.

Synthesis of low molecular weight compounds with complement inhibition activity

An attempt was made to synthesize a series of non-cytotoxic low molecular weight meta-substituted aromatic ethers (2-4, 5-7) and some of their bioisosteres (14-16) and to evaluate their activity on the activation of human complement (classical pathway) and their intrinsic hemolytic activity. The in vitro assay results of the inhibition of complement-mediated hemolysis by these analogues indicate that the aldehydic meta substituted aromatic ethers show inhibitory potency, while carboxylic acid meta substituted aromatic ethers show hemolytic activity. Some of the bioisosteres exhibit both inhibitory as well as hemolytic property.

Topical anti-inflammatory activity of Bauhinia tarapotensis leaves

The topical anti-inflammatory properties of Bauhinia tarapotensis Benth. (Leguminosae) leaves have been studied by the inhibition of the croton oil-induced ear edema in mice. A bioassay-guided fractionation showed an interesting anti-inflammatory activity of the chloroform extract, that justifies the activity of the whole herbal drug. The main anti-inflammatory principles of B. tarapotensis leaves are triterpenic acids of ursane and oleanane series. The antiphlogistic activity of mixtures constituted of two ursane and oleanane isomers with different hydroxylation pattern, in the ratio 2:1, is comparable to that of indomethacin (ID50 ranging from 95 to 147 microg/cm2 and 93 microg/cm2, respectively).

Topical anti-inflammatory activity of extracts and compounds from Thymus broussonettii

The topical anti-inflammatory activity of four extracts from Thymus broussonetii Boiss (Labiatae) leaves, a herbal drug used in Moroccan traditional medicine, has been studied using the croton oil ear test in mice. A bioassay-oriented fractionation revealed that the pharmacological activity is mainly in the chloroform extract. Fractionation and analysis of this extract allowed the identification of ursolic acid and oleanolic acid as the main anti-inflammatory principles. Some flavonoids (luteolin, eriodictyol, thymonin) and glycosides (luteolin-7-O-glucoside, luteolin-3'-O-glucuronide, eriodictyol-7-O-glucoside) were also isolated from the methanol extract.

Topical anti-inflammatory activity of Thymus willdenowii

The topical anti-inflammatory activity of Thymus willdenowii Boiss (Labiatae) leaves, a herbal drug used in Moroccan folk medicine, has been studied using the croton oil ear test in mice. A bioassay-oriented fractionation procedure showed that the activity concentrates in the chloroform extract, which has a potency similar to that of indometacin, the non-steroidal anti-inflammatory drug used as reference (ID50 (dose giving 50% oedema inhibition) = 83 microg cm(-2) and 93 microg cm(-2), respectively). The main compounds responsible for the anti-inflammatory activity of T. willdenowii are ursolic acid and oleanolic acid. The flavonoids luteolin-3'-O-glucuronide and eriodictyol-7-O-glucoside were found for the first time in the genus Thymus.

New insights into the mechanism of action of the anti-inflammatory triterpene lupeol

The pentacyclic triterpene lupeol has been studied for its inhibitory effects on murine models of inflammation and peritoneal macrophage functions in-vitro. Lupeol (0.5 and 1 mg/ear) administered topically suppressed the mouse ear oedema induced by 12-0-tetradecanoyl-phorbol acetate (TPA), being less effective on ear oedema induced by arachidonic acid. Quantitation of the neutrophil specific marker myeloperoxidase demonstrated that its topical activity was associated with reduction in cell infiltration into inflamed tissues. When tested in-vitro, lupeol significantly reduced prostaglandin E2 (PGE2) production from A23187-stimulated macrophages, but failed to affect leukotriene C4 release. It was a weak inhibitor of nitrite release, but dose-dependently suppressed PGE2. Cytokine production (tumour necrosis factor-alpha and interleukin-1beta) was inhibited in the range 10-100 microM in lipopolysaccharide-treated macrophages. This study demonstrated that lupeol possessed anti-inflammatory activity which was likely to depend on its ability to prevent the production of some pro-inflammatory mediators.

Enantioselective synthesis and complement inhibitory assay of A/B-ring partial analogues of oleanolic acid

A series of oleanolic acid A/B-ring partial analogues was synthesized and tested for their complement inhibitory activity as well as cytotoxic properties. All target compounds and one intermediate exhibited moderate complement inhibitory potency. These compounds also showed cytotoxicity on malignant melanoma cell line, SK-MEL.

In vitro inhibitory effects of Daphne oleoides ssp. oleoides on inflammatory cytokines and activity-guided isolation of active constituents

Aerial parts of Daphne oleoides Schreber ssp. oleoides (Thymelaeaceae) are used to treat rheumatoid arthritis and lumbago in Turkish folk medicine. In order to evaluate folkloric utilization, in vitro inhibitory effects of the ethyl acetate extract and fractions obtained from this extract on interleukin 1 (IL-1alpha, IL-1beta) and tumour necrosis factor (TNF-alpha) biosynthesis were studied. Through chemical isolation techniques and activity-guided fractionation process, seventeen compounds were isolated and their structures were elucidated (numbered 1-17). Diterpenoids genkwadaphnin (3) and 1,2-dehydrodaphnetoxin (6) and a coumarin derivative daphnetin (9) showed potent inhibitory activity and were found to be the main active ingredients. Furthermore, gnidilatin (4), gnidilatin-20 palmitate (5), genkwadaphnin-20-palmitate (7) and gnidicin-20-palmitate (8), having diterpenoid structure, and eudesmine (12), wikstromol (13) and matairesinol (14), having lignan structure, were determined to possess moderate inhibitory activity and may have a contributory role in the effect of the remedy.

Synthesis and evaluation of potential complement inhibitory semisynthetic analogs of oleanolic acid

A number of semisynthetic analogs of oleanolic acid have been synthesized and tested for their complement inhibitory, cytotoxic and apoptotic activities. Among these, compounds 10 and 17 exhibited complement inhibitory potency superior to oleanolic acid. Both have also shown a moderate improvement in in vitro therapeutic index (T.I.).

Anticomplement activity of triterpenes from Crataeva nurvala stem bark in adjuvant arthritis in rats

Adjuvant arthritis is widely used as an experimental model for rheumatoid arthritis and inflammation. It is useful in the evaluation of anti-inflammatory drugs. Lupeol is a naturally occuring triterpene isolated from Crataeva nurvala stem bark, and its ester lupeol linoleate was synthesized. The effects of lupeol and lupeol linoleate on the development of complement in adjuvant arthritis in rats were studied and compared with those of indomethacin. The effect of lupeol linoleate in reducing the foot-pad thickness and complement activity in arthritic rats was even greater than that of unesterified lupeol and indomethacin. Because complement is highly involved in inflammation, the results suggest that the anti-inflammatory activity of triterpenes may be due to their anticomplementary activity.

Effects of oleanolic acid and ursolic acid on inhibiting tumor growth and enhancing the recovery of hematopoietic system postirradiation in mice

Two triterpene acids, oleanolic acid (OA) and ursolic acid (UA) were examined for their ability to inhibit the tumor growth and modify hematopoiesis after irradiation in three experimental systems: (a) in vivo anti-tumor activity of implanted tumor by ascitic cells was found to be augmented by addition of OA and UA at a high concentration and inhibited in a dose-dependent manner; (b) in the sublethal whole-body irradiated mice treated with the drugs in the 30 min preirradiation period, enhanced effects of OA and UA on peripheral leukocytes were observed by a different significance, and (c) when these chemicals were administered i.p. to mice 30 min before 4 Gy irradiation, both OA and UA enhanced the postirradiation responses of splenic blastogenesis by PHA. UA was a more potent tumorigenic inhibitor than OA. Combining with the gamma-irradiation, however, there was no significant synergetic effect on their anti-tumor activity. The beneficial effects of OA and UA on hematopoiesis and immunocompetence under this study, suggested they might partially play a role in anti-cancer and, furthermore, with the ability to decrease undesirable radiation damage to the hematopoietic tissue after radiotherapy.