The analgesic and anti-inflammatory effect of new oleanolic acid acyloxyimino derivative

Recent advances in the chemistry and biology of oleanolic acid and its derivatives

The pentacyclic triterpenes represent a significant class of plant bioactives with a variety of structures and a wide array of biological activities. These are biosynthetically produced via the mevalonate pathway although occasionally mixed pathways may also occur to introduce structural divergence. Oleanolic acid is one of the most explored bioactive from this class of compounds and possesses a broad spectrum of pharmacological and biological activities including liver protection, anti-cancer, atherosclerosis, anti-inflammation, antibacterial, anti-HIV, anti-oxidative, anti-diabetic etc. This review provides an overview of the latest research findings, highlighting the versatile medicinal and biological potential of oleanolic and its future prospects.

Effect of prepared herbal mouthwash in maintaining the oral health of school children: A single-blind randomised control trial

BACKGROUND AND AIM

Oral health is a vital indicator of overall well-being, quality of life, and general health, with historical roots in Unani medicine (i.e. preventive measures, oral hygiene, and treatment). This study aims to assess the efficacy and safety of prepared herbal mouthwash in maintaining oral health among school children.

EXPERIMENTAL PROCEDURE

110 schoolchildren were randomly assigned to the test group (treated with herbal mouthwash -Anacyclus pyrenthrum DC, Punica granutum (pericarp), Capparis spinosa (root bark), and Quercus infectoria Oliv (galls)) and the control group (treated with 0.2 % Chlorhexidine Mouthwash) for 30-days. The response was assessed by DMFT, Salivary pH, Oral hygiene index-simplified (OHI-S), Plaque index (Loe & Silness) (PI), Plaque index simplified (O'Leary et al., 1972) (PI-S), Gingival Index (Löe-Silness) (GI), and Bleeding on probing (BOP) on baseline and 30th day GI and PI were further assessed on 60th, 90th and 120th days to determine the sustainable effect of the intervention.

RESULTS

After treatment, Mean OHI-S, PI, PI-S, GI and BOP significantly reduced on the 30th day from baseline (p ≤ 0.001) in both groups. After discontinuing intervention, both groups showed significantly lower PI and GI scores on the 120th day from baseline. (p < 0.001).

CONCLUSION

This study revealed that prepared mouthwash is safe and significantly effective in maintaining oral health, and it could be used as an adjunct to mechanical oral hygiene measures.

Biological Activities of Novel Oleanolic Acid Derivatives from Bioconversion and Semi-Synthesis

Oleanolic acid (OA) is a vegetable chemical that is present naturally in a number of edible and medicinal botanicals. It has been extensively studied by medicinal chemists and scientific researchers due to its biological activity against a wide range of diseases. A significant number of researchers have synthesized a variety of analogues of OA by modifying its structure with the intention of creating more potent biological agents and improving its pharmaceutical properties. In recent years, chemical and enzymatic techniques have been employed extensively to investigate and modify the chemical structure of OA. This review presents recent advancements in medical chemistry for the structural modification of OA, with a special focus on the biotransformation, semi-synthesis and relationship between the modified structures and their biopharmaceutical properties.

Synthesis of Novel Acetyl-11-keto-β-boswellic Acid Derivatives as Potential Anti-GBM Agents

Acetyl-11-keto-β-boswellic acid (AKBA) is known to inhibit the growth of glioblastoma (GBM) cells and subcutaneous GBM. A series of acetyl-11-keto-β-boswellic acid (AKBA) derivatives containing the oxime-ester functionality or amide side chains were synthesized, and their anti-GBM activities were evaluated. Some of these compounds exhibited significant inhibitory activity against cell proliferation in U87 and U251 GBM cell lines, with IC50 values in the micromolar concentration range. Cellular thermal shift analysis showed that A-01 and A-10 improved the thermal stability of FOXM1, indicating that these highly active compounds may directly bind to FOXM1 in cells. Docking studies of the two most active compounds, A-01 and A-10, revealed key interactions between these compounds and the active site of FOXM1, in which the amide moiety at the C-24 position was essential for improving the activity. These results suggested that A-10 is a suitable lead molecule for the development of FOXM1 inhibitors. Thus, the rational design of AKBA derivatives with amide side chains holds significant potential for discovering of a new class of triterpenoids capable of inhibiting GBM cell proliferation.

Polymorphism of Butyl Ester of Oleanolic Acid—The Dominance of Dispersive Interactions over Electrostatic

Oleanolic (OA) and glycyrrhetinic acids (GE), as well as their derivatives, show a variety of pharmacological properties. Their crystal structures provide valuable information related to the assembly modes of these biologically active compounds. In the known-to-date crystals of OA esters, their 11-oxo derivatives, and GE ester crystals, triterpenes associate, forming different types of ribbons and layers whose construction is based mainly on van der Waals forces and weak C-H···O interactions. New crystal structures of 11-oxo OA methyl ester and the polymorph of OA butyl ester reveal an alternative aggregation mode. Supramolecular architectures consist of helical chains which are stabilized by hydrogen bonds of O-H···O type. It was found that two polymorphic forms of butyl OA ester (layered and helical) are related monotropically. In a structure of metastable form, O-H···O hydrogen bonds occur, while the thermodynamically preferred phase is governed mainly by van der Waals interactions. The intermolecular interaction energies calculated using CrystalExplorer, PIXEL, and Psi4 programs showed that even in motifs formed through O-H···O hydrogen bonds, the dispersive forces have a significant impact.

Recent advances in medicinal chemistry of oleanolic acid derivatives

Oleanolic acid (OA), a ubiquitous pentacyclic oleanane-type triterpene isolated from edible and medicinal plants, exhibits a wide spectrum of pharmacological activities and tremendous therapeutic potential. However, the undesirable pharmacokinetic properties limit its application and development. Numerous researches on structural modifications of OA have been carried out to overcome this limitation and improve its pharmacokinetic and therapeutic properties. This review aims to compile and summarize the recent progresses in the medicinal chemistry of OA derivatives, especially on structure-activity relationship in the last few years (2010-2021). It gives insights into the rational design of bioactive derivatives from OA scaffold as promising therapeutic agents.

Discovery of novel phenoxypyridine as promising protoporphyrinogen IX oxidase inhibitors

Protoporphyrinogen oxidase (PPO, EC 1.3.3.4) is a significant target for the discovery of novel bleaching herbicides. Starting from the active fragments of several known commercial herbicides, a series of PPO inhibitors with diphenyl ether scaffolds were designed and synthesized by substructure splicing and bioisosterism methods. The greenhouse herbicidal activity and the PPO inhibitory activity in vitro were measured. The results showed that the novel synthesized compounds have good PPO inhibitory activity, and the IC₅₀ value against corn PPO ranges from 0.032 ± 0.008 mg/L to 3.245 ± 0.247 mg/L. Among all target compounds, compound P2 showed the best herbicidal activity, with a half inhibitory concentration (IC₅₀) of 0.032 ± 0.008 mg/L. In addition, the molecular docking results showed that the benzene ring part of compound P2 can form a π-π stacking with PHE-392, and the trifluoromethyl group and ARG-98 form two hydrogen bonds. Crop safety experiments and cumulative concentration analysis experiments indicated that compound P2 can be used for weed control in rice, wheat, soybean and corn. Therefore, compound P2 can be selected to develop potential lead compounds for novel PPO inhibitors.

Design, Synthesis, and Herbicidal Activity of Diphenyl Ether Derivatives Containing a Five-Membered Heterocycle

Protoporphyrinogen oxidase (PPO, EC 1.3.3.4) is an important target for discovering novel herbicides, and it causes bleaching symptoms by inhibiting the synthesis of chlorophyll and heme. In this study, the active fragments of several commercial herbicides were joined by substructure splicing and bioisosterism, and a series of novel diphenyl ether derivatives containing five-membered heterocycles were synthesized. The greenhouse herbicidal activity and the PPO inhibitory activity in vitro were discussed in detail. The results showed that most compounds had good PPO inhibitory activity, and target compounds containing trifluoromethyl groups tended to have higher activity. Among them, compound G4 showed the best inhibitory activity, with a half-maximal inhibitory concentration (IC₅₀) of 0.0468 μmol/L, which was approximately 3 times better than that of oxyfluorfen (IC₅₀ = 0.150 μmol/L). In addition, molecular docking indicated that compound G4 formed obvious π-π stacking interactions and hydrogen bond interactions with PHE-392 and ARG-98, respectively. Remarkably, compound G4 had good safety for corn, wheat, rice, and soybean, and the cumulative concentration in crops was lower than that of oxyfluorfen. Therefore, compound G4 can be used to develop potential lead compounds for novel PPO inhibitors.

Synthesis and bioactivities evaluation of oleanolic acid oxime ester derivatives as α-glucosidase and α-amylase inhibitors

Different oleanolic acid (OA) oxime ester derivatives (3a-3t) were designed and synthesised to develop inhibitors against α-glucosidase and α-amylase. All the synthesised OA derivatives were evaluated against α-glucosidase and α-amylase in vitro. Among them, compound 3a showed the highest α-glucosidase inhibition with an IC₅₀ of 0.35 µM, which was ∼1900 times stronger than that of acarbose, meanwhile compound 3f exhibited the highest α-amylase inhibitory with an IC₅₀ of 3.80 µM that was ∼26 times higher than that of acarbose. The inhibition kinetic studies showed that the inhibitory mechanism of compounds 3a and 3f were reversible and mixed types towards α-glucosidase and α-amylase, respectively. Molecular docking studies analysed the interaction between compound and two enzymes, respectively. Furthermore, cytotoxicity evaluation assay demonstrated a high level of safety profile of compounds 3a and 3f against 3T3-L1 and HepG2 cells.

Highlights

Oleanolic acid oxime ester derivatives (3a–3t) were synthesised and screened against α-glucosidase and α-amylase.

Compound 3a showed the highest α-glucosidase inhibitory with IC50 of 0.35 µM.

Compound 3f presented the highest α-amylase inhibitory with IC50 of 3.80 µM.

Kinetic studies and in silico studies analysed the binding between compounds and α-glucosidase or α-amylase.

Anti-Cancer Potential of Synthetic Oleanolic Acid Derivatives and Their Conjugates with NSAIDs

Naturally occurring pentacyclic triterpenoid oleanolic acid (OA) serves as a good scaffold for additional modifications to achieve synthetic derivatives. Therefore, a large number of triterpenoids have been synthetically modified in order to increase their bioactivity and their protective or therapeutic effects. Moreover, attempts were performed to conjugate synthetic triterpenoids with non-steroidal anti-inflammatory drugs (NSAIDs) or other functional groups. Among hundreds of synthesized triterpenoids, still the most promising is 2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oic acid (CDDO), which reached clinical trials level of investigations. The new group of synthetic triterpenoids are OA oximes. The most active among them is 3-hydroxyiminoolean-12-en-28-oic acid morpholide, which additionally improves the anti-cancer activity of standard NSAIDs. While targeting the Nrf2 and NF-κB signaling pathways is the main mechanism of synthetic OA derivatives′ anti-inflammatory and anti-cancer activity, most of these compounds exhibit multifunctional activity, and affect cross-talk within the cellular signaling network. This short review updates the earlier data and describes the new OA derivatives and their conjugates in the context of modification of signaling pathways involved in inflammation and cell survival and subsequently in cancer development.

The in vitro and in vivo study of oleanolic acid indole derivatives as novel anti-inflammatory agents: Synthesis, biological evaluation, and mechanistic analysis

Oleanolic acid (OA) is a well-known natural product possessing many important pharmacological activities; however, its weak bioactivities significantly restrict the potential application in drug development. The structural modification of oleanolic acid is an effective mean to enhance its bioactivity with lower toxicity but it is challenging. In the present study, we systematically synthesized a series of new 11-oxooleanolic acid derivatives and evaluated their anti-inflammatory activities with a LPS induced BV2 cells inflammation model and a 12-O-tetradecanoyl phorbol-13-acetate (TPA) induced ear inflammation mice model. It was found that compounds 8 and 9 show more potent anti-inflammatory effects than OA and exhibit a low cytotoxicity. The possible mechanism of action was also investigated. The in vitro and in vivo results revealed that these two new 11-oxooleanolic acid derivatives may exert anti-inflammatory activities through the inhibition of NO, pro-inflammatory cytokines and chemokines (IL-1β, IL-6, IL-12, TNF-α, MCP-1 and MIP-1α) and upregulation of anti-inflammatory cytokines (IL-10), which may be caused by inhibiting the activation of NF-κB, MAPKs and PI3K/Akt related inflammatory signaling pathways and the activation of Nrf2/HO-1 signaling pathway. The results suggest that these two 11-oxooleanolic acid derivatives may be potential candidates for further anti-inflammatory drug development and our study demonstrated an important and practical strategy for drug discovery through the rational modification of natural products.

Cytotoxic, analgesic and anti-inflammatory activity of colchicine and its C-10 sulfur containing derivatives

10-Alkylthiocolchicines have been obtained and characterized by spectroscopic methods and their biological activities as: cytotoxic, anti-inflammatory and analgesic activities have been tested. Cytotoxic activity against SKOV-3 ovarian cell line for 10-alkylthiocolchicine analogues was reported and tested compounds showed to be more active than commonly used doxorubicin. Some of tested C-10 alkylthiolated colchicines have been found to exhibit cytotoxicity at levels comparable to that of the natural product-colchicine. 10-Methylthiocolchicine has IC50 = 8 nM and 10-ethylthiocolchicine has IC50 = 47 nM in comparison to colchicine IC50 = 37 nM. Moreover for 10-alkylthioderivatives apoptosis test, cyclin B1 and cell cycle tests were performed. 10-n-Butylthiocolchicine was tested for anti-inflammatory and analgesic activities it showed to produce analgesic rather than anti-inflammatory effect.

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 Comparative Immunotropic Activity of Carrageenan, Chitosan and Their Complexes

The immunotropic activity of polyelectrolyte complexes (PEC) of κ-carrageenan (κ-CGN) and chitosan (CH) of various compositions was assessed in comparison with the initial polysaccharides in comparable doses. For this, two soluble forms of PEC, with an excess of CH (CH:CGN mass ratios of 10:1) and with an excess of CGN (CH: CGN mass ratios of 1:10) were prepared. The ability of PEC to scavenge NO depended on the content of the κ-CGN in the PEC. The ability of the PEC to induce the synthesis of pro-inflammatory (tumor necrosis factor-α (TNF-α)) and anti-inflammatory (interleukine-10 (IL-10)) cytokines in peripheral blood mononuclear cell was determined by the activity of the initial κ-CGN, regardless of their composition. The anti-inflammatory activity of PEC and the initial compounds was studied using test of histamine-, concanavalin A-, and sheep erythrocyte immunization-induced inflammation in mice. The highest activity of PEC, as well as the initial polysaccharides κ-CGN and CH, was observed in a histamine-induced exudative inflammation, directly related to the activation of phagocytic cells, i.e., macrophages and neutrophils.

Oleanolic acid oxime derivatives and their conjugates with aspirin modulate the NF-κB-mediated transcription in HepG2 hepatoma cells

The aim of this study was to evaluate the effect of new oleanolic acid oxime (OAO) derivatives and their conjugates with aspirin (ASP) on the expression and activation of NF-κB in human hepatoma HepG2 cells. OAO derivatives showed a stronger cytotoxic effect against HepG2 cells compared with their conjugates with aspirin. Moreover, conjugation of OAO with ASP led to enhanced downregulation of NF-κB expression and activation. Among the hybrids with ASP, compounds: 19, 3-(2-acetoxy)benzoyloxyiminoolean-12-en-28-oic acid morpholide and 13, 3-(2-acetoxy)benzoyloxyiminoolean-12-en-28-oic acid methyl ester, differing, respectively, in morpholide and methyl ester groups at the C-17 position of oleanolic acid (OA) molecule were the most efficient. COX-2 transcript and protein levels were also diminished after treatment with these compounds. The results of this study indicate that the new derivatives of OAO and particularly their conjugates with ASP, downregulate the expression of COX-2 in HepG2 cells by modulating the NF-κB signaling pathway and suggest their potential application in the prevention of liver inflammation and cancer.

Enhancing anticancer activity through the combination of bioreducing agents and triterpenes

AIM

Triterpenes are natural compounds, whose wide biological activity predestines them for application as promising new chemotherapeutics. In this paper, we report the results of our investigations into the substitution of oleanolic acid with aromatic and nitroaromatic moieties acting as bioreducing agents.

RESULTS

The process of reduction of nitro groups was investigated through cyclic voltammetry, UV-Vis and electron paramagnetic resonance spectroelectrochemistry. The cytotoxic activity against selected cancer cell lines was determined, showing a significant increase in cytotoxicity when the triterpene is equipped with a nitroaromatic moiety.

CONCLUSION

We believe this approach to the functionalization is promising in terms of enhancing anticancer activity. We also indicate electrochemical techniques as advantageous preclinical screening methods for the identification of cytotoxic agents.

Design and synthesis of novel oleanolic acid based chromenes as anti-proliferative and anti-inflammatory agents

A novel approach has been developed for the synthesis of oleanolic acid based anti-proliferative and anti-inflammatory chromenes.

Oleanolic Acid and Its Derivatives: Biological Activities and Therapeutic Potential in Chronic Diseases

The increasing demand for natural products as an alternative therapy for chronic diseases has encouraged research into the pharmacological importance of bioactive compounds from plants. Recently, there has been a surge of interest in the therapeutic potential of oleanolic acid (OA) in the prevention and management of chronic diseases. Oleanolic acid is a pentacyclic triterpenoid widely found in plants, including fruits and vegetables with different techniques and chromatography platforms being employed in its extraction and isolation. Several studies have demonstrated the potential therapeutic effects of OA on different diseases and their symptoms. Furthermore, oleanolic acid also serves as a framework for the development of novel semi-synthetic triterpenoids that could prove vital in finding therapeutic modalities for various ailments. There are recent advances in the design and synthesis of chemical derivatives of OA to enhance its solubility, bioavailability and potency. Some of these derivatives have also been therapeutic candidates in a number of clinical trials. This review consolidates and expands on recent reports on the biological effects of oleanolic acid from different plant sources and its synthetic derivatives as well as their mechanisms of action in in vitro and in vivo study models. This review suggests that oleanolic acid and its derivatives are important candidates in the search for alternative therapy in the treatment and management of chronic diseases.

Strong and Long-Lasting Antinociceptive and Anti-inflammatory Conjugate of Naturally Occurring Oleanolic Acid and Aspirin

The conjugate 8 was obtained as a result of condensation of 3-hydroxyiminooleanolic acid morfolide (7) and aspirin in dioxane. Analgesic effect of OAO-ASA (8) for the range of doses 0.3–300.0 mg/kg (p.o.) was performed in mice using a hot-plate test. Anti-inflammatory activity was assessed on carrageenan-induced paw edema in rats for the same range of doses. The conjugate OAO-ASA (8) did not significantly change locomotor activity of mice, therefore sedative properties of the compound should be excluded. The compound 8 proved a simple, proportional, dose-dependent analgesic action and expressed strong anti-inflammatory activity showing a reversed U-shaped, dose-dependent relation with its maximum at 30.0 mg/kg. After its combined administration with morphine (MF, 5.0 mg/kg, s.c.) the lowering of antinociceptive activity was found; however, the interaction with naloxone (NL, 3.0 mg/kg, s.c.) did not affect the antinociceptive effect of OAO-ASA (8), therefore its opioid mechanism of action should be rather excluded. After combined administration with acetylsalicylic acid (ASA, 300.0 mg/kg, p.o.) in hot-plate test, the examined compound 8 enhanced the antinociceptive activity in significant way. It also shows that rather the whole molecule is responsible for the antinociceptive and anti-inflammatory effect of the tested compound 8, however, it cannot be excluded that the summarizing effect is produced by ASA released from the compound 8 and the rest of triterpene derivative. The occurrence of tolerance for triterpenic derivative 8 was not observed, since the analgesic and anti-inflammatory effects after chronic administration of the conjugate OAO-ASA (8) was on the same level as after its single treatment. It seemed that the anti-inflammatory mechanism of action of OAO-ASA (8) is not simple, even its chronic administration lowered both blood concentration of IL-6 and mRNA IL-6 expression. However, the effects of the conjugate OAO-ASA (8) on TNF-α level and mRNA expression were opposite. Moreover, compound 8 did not change unequivocally mRNA TLR1, and TLR3 expression. Concluding, the obtained results regarding the antinociceptive and anti-inflammatory activity of new conjugate of oleanolic acid oxime and acetylsalicylic acid (OAO-ASA 8) are very interesting, but for explanation of its mechanism of action, more detailed studies are necessary.

Hybrid Compounds Strategy in the Synthesis of Oleanolic Acid Skeleton-NSAID Derivatives

The current study focuses on the synthesis of several hybrid individuals combining a natural oleanolic acid skeleton and synthetic nonsteroidal anti-inflammatory drug moieties (NSAIDs). It studied structural modifications of the oleanolic acid structure by use of the direct reactivity of hydroxyl or hydroxyimino groups at position C-3 of the triterpenoid skeleton with the carboxylic function of anti-inflammatory drugs leading to new perspective compounds with high potential pharmacological activities. Novel ester- and iminoester-type derivatives of oleanolic unit with the different NSAIDs, such as ibuprofen, aspirin, naproxen, and ketoprofen, were obtained and characterized. Moreover, preliminary research of compounds obtaining structure stability under acidic conditions was examined and the PASS method of prediction of activity spectra for substances was used to estimate the potential biological activity of these compounds.

Topical Anti-inflammatory Activity of New Hybrid Molecules of Terpenes and Synthetic Drugs

The aim of the study was to assess changes in the activity of anti-inflammatory terpenes from Chilean medicinal plants after the formation of derivatives incorporating synthetic anti-inflammatory agents. Ten new hybrid molecules were synthesized combining terpenes (ferruginol (1), imbricatolic acid (2) and oleanolic acid (3)) with ibuprofen (4) or naproxen (5). The topical anti-inflammatory activity of the compounds was assessed in mice by the arachidonic acid (AA) and 12-O-tetradecanoyl phorbol 13-acetate (TPA) induced ear edema assays. Basal cytotoxicity was determined towards human lung fibroblasts, gastric epithelial cells and hepatocytes. At 1.4 µmol/mouse, a strong anti-inflammatory effect in the TPA assay was observed for oleanoyl ibuprofenate 12 (79.9%) and oleanoyl ibuprofenate methyl ester 15 (80.0%). In the AA assay, the best activity was observed for 12 at 3.2 µmol/mouse, with 56.8% reduction of inflammation, in the same range as nimesulide (48.9%). All the terpenyl-synthetic anti-inflammatory hybrids showed better effects in the TPA assay, with best activity for 6, 12 and 15. The cytotoxicity of the compounds 8 and 10 with a free COOH, was higher than that of 2. The derivatives from 3 were less toxic than the triterpene. Several of the new compounds presented better anti-inflammatory effect and lower cytotoxicity than the parent terpenes.

Endogenous opiates and behavior: 2013

This paper is the thirty-sixth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2013 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia; stress and social status; tolerance and dependence; learning and memory; eating and drinking; alcohol and drugs of abuse; sexual activity and hormones, pregnancy, development and endocrinology; mental illness and mood; seizures and neurologic disorders; electrical-related activity and neurophysiology; general activity and locomotion; gastrointestinal, renal and hepatic functions; cardiovascular responses; respiration and thermoregulation; and immunological responses.

Oleanolic acid co-administration alleviates ethanol-induced hepatic injury via Nrf-2 and ethanol-metabolizing modulating in rats

Alcoholic liver disease (ALD) is one of the leading causes of death in the world. Oxidative stress plays an important role in the pathogenesis of alcohol-induced liver injury. Our previous results have found that oleanolic acid (OA), a liver protective agent, plays a potent antioxidant activity in hepatocyte. In the present study, the protective effects of OA co-administration on ethanol-induced oxidative injury in rats were investigated through detecting hepatic histopathology, antioxidant enzymes, ethanol metabolic enzymes and inflammatory factors. Preventions of ethanol-induced oxidative injury by OA were reflected by markedly decreased serum activities of AST, ALT and significantly increased the hepatic ATP level. In addition, the increase of the hepatic TG content, MDA level and the decrease of hepatic GSH level, SOD activity, CAT activity induced by ethanol were significantly inhibited by OA co-administration. Furthermore, OA could also elevate the protein expressions and nuclear translocation of antioxidant transcription factor Nrf-2 and then up-regulated antioxidant enzymes expressions of HO-1, SOD-1 and GR. Moreover, OA co-administration can significantly reduce the activity and expressions of CYP2E1 and ADH, which has characteristic of generation ROS mediated oxidative stress and acetaldehyde respectively. Furthermore, OA co-administration could inhibition of the generation of inflammatory factors TNF-α and IL-6. Those above results indicated that OA co-administration can protect rats against ethanol-induced liver injury by induction Nrf-2 related antioxidant to maintain redox balance and modulating the ethanol-metabolizing and inflammatory pathway.

Recent advances in synthesis and biological activity of triterpenic acylated oximes

During the last few decades more and more attention has been paid to triterpenes-a group of compounds with five- or four-ring skeleton and carboxyl, hydroxyl or oxo groups. Triterpenes with unsubstituted C-3 hydroxyl group can be easily transformed into appropriate ketones and then into oximes. The carbonyl group can be created not only from the hydroxyl group at C-3 position, but also at C-2, C-12 or C-28 positions. Several methods of creation of two = NOH groups within one molecule of triterpene are known. There are also known triterpenes with two carbonyl groups, e.g. at C-3 and C-11 positions, which differ in reactivity: among them only C-3 group can be transformed into oxime. A reactive hydroxyimine group can undergo the action of acylating agents, such as carboxylic acids or their derivatives, also the ones with significant pharmacological activity. Acyl derivatives of triterpenic oximes exhibit important pharmacological activity. The biological tests performed with the use of cell cultures inoculated with viruses showed inhibitory activity of some triterpenic acyloximes against type 1 HSV (H7N1), ECHO-6 and HIV-1 viruses. Another acylated oximes derived from triterpenes shown cytotoxic or antiproliferative activity against many lines of cancer cells. In many cases the pharmacological effects of the tested acyloxyiminotriterpenes were comparable to those of appropriate standard drugs. One of the newest application of acyl derivatives of triterpenic oximes is their ability to form organogels.