Olive-Derived Hydroxytyrosol Shows Anti-inflammatory Effect without Gastric Damage in Rats

Synthesis, biological evaluation and molecular docking study of some new 4-aminosalicylic acid derivatives as anti-inflammatory and antimycobacterial agents

In this study, new derivatives of the antitubercular and anti-inflammatory drug, 4-aminosaliclic acids (4-ASA) were synthesized, characterized, and evaluated for these activities. In vivo and in viro evaluation of anti-inflammatory activity revealed that compounds 10, 19 and 20 are the most active with potent cyclooxygenase-2 (COX-2) and 5-lipooxgenase (5-LOX) inhibition and without causing gasric lesions. The minimum inhibitory concentrations (MIC) of the newly synthesized compound were, also, measured against Mycobacterium tuberculosis H37RV. Among the tested compounds 17, 19 and 20 exhibited significant activities against the growth of M. tuberculosis. 20 is the most potent with (MIC 1.04 µM) 2.5 folds more potent than the parent drug 4-ASA. 20 displayed low cytotoxicity against normal cell providing a high therapeutic index. Important structure features were analyzed by docking and structure-activity relationship analysis to give better insights into the structural determinants for predicting the anti-inflammatory and anti-TB activities. Our results indicated that compounds 19 and 20 are potential lead compounds for the discovery of dual anti-inflammatory and anti-TB drug candidates.

A novel strategy against hepatitis B virus: Glycyrrhetnic acid conjugated multi-component synergistic nano-drug delivery system for targeted therapy

It is well known that Glycyrrhetnic acid (GA) has significant liver-targeting and anti-inflammatory effects. Syringopicroside (SYR) and Hydroxytyrosol (HT), the active components of the Chinese herb Syringa oblata Lindl, have earned great reputation for their potential in preventing or treating viral hepatitis type B. Therefore, we loaded SYR and HT into GA-conjugated PEG-PLGA, so that they could target the liver in additional to exerting their own pharmacological effects in a synergistic. However, the in vivo targeting and the low bioavailability of SYR and HT pose a huge challenge. Therefore, we synthesized GA-conjugated multi-component nano-drug delivery system (SH-GPP). SH-GPP had a regular spherical shape with a uniform size distribution of 110.5 ± 3.18 nm. We further evaluated the effects of SH-GPP in vitro and in vivo. In the in vivo experiment, we evaluated the following parameters: the serum ALT and AST values; liver tissue homogenate MDA and SOD; HE staining of the pathological liver sections; and the liver coefficient. In the in vitro studies, the following parameters were evaluated: cellular uptake of SH-GPP; wound healing/scratch assay; cellular apoptosis; cell cycle; HBsAg; and HBeAg content. SH-GPP had better anti-hepatitis B effect than Syringopicroside and hydroxytyrosol (SH) and NPP alone. The targeting ability of GA enabled HT and SYR in GPP to reach the liver accurately, and played a synergistic role to maximize their therapeutic effects. This study provides a novel strategy against hepatitis B virus, and also provides a feasible scheme for improving the low bioavailability of the active components of traditional Chinese medicine.

Novel Bile Salt Stabilized Vesicles-Mediated Effective Topical Delivery of Diclofenac Sodium: A New Therapeutic Approach for Pain and Inflammation

The oral delivery of diclofenac sodium (DNa), a non-steroidal analgesic, anti-inflammatory drug, is associated with various gastrointestinal side effects. The aim of the research was to appraise the potential of transdermal delivery of DNa using bilosomes as a vesicular carrier (BSVC) in inflamed paw edema. DNa-BSVCs were elaborated using a thin-film hydration technique and optimized using a 3¹.2² multilevel categoric design with Design Expert^® software 10 software (Stat-Ease, Inc., Minneapolis, MI, USA). The effect of formulation variables on the physicochemical properties of BSVC, as well as the optimal formulation selection, was investigated. The BSVCs were evaluated for various parameters including entrapment efficiency (EE%), vesicle size (VS), zeta potential (ZP) and permeation studies. The optimized BSVC was characterized for in vitro release, Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and incorporated into hydrogel base. The optimized DNa-BSVC gel effectiveness was assessed in vivo using carrageenan-induced paw edema animal model via cyclooxygenase 2 (COX-2), interleukin 6 (IL-6), Hemooxygenase 1 (HO-1) and nuclear factor-erythroid factor2-related factor 2 (Nfr-2) that potentiate anti-inflammatory and anti-oxidant activity coupled with histopathological investigation. The resulting vesicles presented VS from 120.4 ± 0.65 to 780.4 ± 0.99 nm, EE% from 61.7 ± 3.44 to 93.2 ± 2.21%, ZP from −23.8 ± 2.65 to −82.1 ± 12.63 mV and permeation from 582.9 ± 32.14 to 1350.2 ± 45.41 µg/cm². The optimized BSVCs were nano-scaled spherical vesicles with non-overlapped bands of their constituents in the FTIR. Optimized formulation has superior skin permeability ex vivo approximately 2.5 times greater than DNa solution. Furthermore, histological investigation discovered that the formed BSVC had no skin irritating properties. It was found that DNa-BSVC gel suppressed changes in oxidative inflammatory mediators (COX-2), IL-6 and consequently enhanced Nrf2 and HO-1 levels. Moreover, reduction of percent of paw edema by about three-folds confirmed histopathological alterations. The results revealed that the optimized DNa-BSVC could be a promising transdermal drug delivery system to boost anti-inflammatory efficacy of DNa by enhancing the skin permeation of DNa and suppressing the inflammation of rat paw edema.

Drug Discovery of New Anti-Inflammatory Compounds by Targeting Cyclooxygenases

The goal of achieving anti-inflammatory efficacy with the fewest possible adverse effects through selective COX-2 inhibition is still being investigated in order to develop drugs with safe profiles. This work shows the efficacy and safety profile of two novel benzimidazole piperidine and phenoxy pyridine derivatives in reaching this goal, which would be considered a major achievement in inflammatory therapy. The compounds were evaluated by virtual screening campaign, in vitro cyclooxygenase 1 and 2 (COX-1 and COX-2) inhibition, in vivo carrageenan-induced rat paw edema assay, cytotoxicity against Raw264.7 cells, and histopathological examination of rat paw and stomach. Two new compounds, compound 1 ([(2-{[3-(4-methyl-1H-benzimidazol-2-yl)piperidin-1-yl]carbonyl}phenyl)amino]acetic acid) and compound 2 (ethyl 1-(5-cyano-2-hydroxyphenyl)-4-oxo-5-phenoxy-1,4-dihydropyridine-3-carboxylate) showed high selectivity against COX-2, favourable drug-likeness and ADME descriptors, a lack of cytotoxicity, relived paw edema, and inflammation without noticeable side effects on the stomach. These two compounds are promising new NSAIDs.

Bioactivity-guided isolation of immunomodulatory compounds from the fruits of Ligustrum lucidum

ETHNOPHARMACOLOGICAL RELEVANCE

The fruits of Ligustrum lucidum (FLL) W.T. Aiton (Oleaceae) is included in the 2020 "Chinese Pharmacopoeia" and is widely used in traditional Chinese medicine as a tonic. In recent years, FLL has been reported to improve immune function, but the bioactive compounds and mechanisms of FLL remain poorly characterized.

AIM OF THE STUDY

To identify FFL compounds with strong immune activity and explore their molecular mechanisms.

MATERIALS AND METHODS

The phagocytic activity of RAW264.7 macrophages and proliferation activity of spleen lymphocytes were used to guide the isolation of bioactive compounds from FLL extracts. Lymphocyte subpopulations, Ca²⁺ concentrations, and surface molecule expression were analyzed using flow cytometry. Cytokine secretion was examined using ELISA. FITC-OVA uptake was observed using fluorescence microscopy. NF-κB activation was analyzed using western blotting.

RESULTS

The extraction and isolation produced ten compounds, namely oleuropeinic acid, nuezhenide, isonuezhenide, salidroside, isoligustrosidic acid, ligulucidumosides A, 8(E)-nuezhenide, hydroxytyrosol, oleuropein, and p-hydroxyphenethyl 7-β-D-glucosideelenolic acid ester were isolated and identified from FLL-Bu-30%. Immunoactivity experiments showed that hydroxytyrosol had the strongest macrophage phagocytotic and lymphocyte proliferation-promoting activities. Further studies showed that hydroxytyrosol could significantly enhance lymphocyte subsets CD3⁺, CD4⁺/CD8⁺, and CD3⁺CD4^-CD8^-, promote IL-4, IFN-γ, and TNF-α secretion, and increase intracellular Ca²⁺ concentrations. In addition, the results from RAW264.7 macrophages showed that hydroxytyrosol increased FITC-OVA uptake, induced TNF-α and IL-1β production, upregulated MHC-II, CD80, and CD86 expression, promoted cytoplasmic IκB-α degradation, and increased nuclear NF-κB p65 levels.

CONCLUSION

Our study provides substantial evidence regarding the mechanism of the immunomodulatory effects of compounds from FLL.

Mycophenolate suppresses inflammation by inhibiting prostaglandin synthases: a study of molecular and experimental drug repurposing

Mycophenolate mofetil is an established anti-proliferative and immune-suppressive agent that minimizes the proliferation of inflammatory cells by interfering with nucleic acid synthesis. Herein, we report our discovery of the prostaglandin inhibiting properties of MMF, which offers new applications for the drug in the treatment of inflammatory diseases. The estimated values of IC₅₀MMF_COX-1, IC₅₀MMF_COX-2, and IC₅₀MMF_5-LOX were 5.53, 0.19, and 4.47 µM, respectively. In contrast, mycophenolic acid (MPA) showed slightly stronger inhibition: IC₅₀MPA_COX-1, IC₅₀MPA_COX-2, and IC₅₀MPA_5-LOX were 4.62, 0.14, and 4.49 µM, respectively. These results indicate that MMF and MPA are, respectively, 28.6 and 33 times more selective for cyclooxygenase-2 than for cyclooxygenase-1, which implies that MMF would have less impact on the gastric mucosa than most nonselective, nonsteroidal anti-inflammatory drugs. Furthermore, MMF provided dose-dependent relief of acute inflammation in the carrageenan-induced rat paw edema test, with results comparable to those of celecoxib and indomethacin. Molecular dynamics simulations indicated that the MMF bond with COX-2 was stable, as evidenced by a low root-mean-square deviation of atomic positions, complementary per-residue root-mean-square fluctuation, and 0–4 hydrogen bonds during the 50-ns simulation time. Therefore, MMF provides immune-suppressing, cyclooxygenase-inhibiting, and inflammation-relieving properties. Our results indicate that MMF can be 1) repositioned for inflammation treatment without the need for further expensive clinical trials, 2) used for local acute inflammations, and 3) used as a sparing agent for other steroid and non-steroid anti-inflammatory medications, especially in topical applications.

Hydroxytyrosol ameliorates oxidative challenge and inflammatory response associated with lipopolysaccharide-mediated sepsis in mice

Hydroxytyrosol (HT) is among the main bioactive ingredients isolated from olive tree with a variety of biological and pharmacological activities. In the current study, the antioxidative and anti-inflammatory activities of HT were distinguished in the splenic tissue following lipopolysaccharide (LPS)-mediated septic response. Thirty-five Swiss mice were divided into five groups (n = 7): control, HT (40 mg/kg), LPS (10 mg/kg), HT 20 mg+LPS and HT 40 mg+LPS. HT was administered for 10 days, while a single LPS dose was applied. The obtained findings demonstrate that HT administration enhanced the survival rate and decreased lactate dehydrogenase level in LPS-challenged mice. Treatment with HT inhibited the incidence of oxidative damage in splenic tissue through decreasing lipoperoxidation and increasing antioxidant molecules, namely glutathione, superoxide dismutase and catalase. HT also decreased total leukocytes count, C-reactive protein, monocyte chemoattractant protein-1, and myeloperoxidase levels. Additionally, HT suppressed the production levels of tumor necrosis factor-α, interleukin-1β, and interleukin-6. Moreover, mRNA expression of inducible nitric oxide synthase and nitric oxide production were increased after HT administration. Furthermore, HT supplementation resulted in a downregulation of p38 mitogen-activated protein kinase, inhibited the activation of the nuclear factor kappa-B from the nucleus to the cytoplasm, and attenuated infiltration of activated immune cells and tissue injury following LPS injection. Collectively, these findings demonstrate the antioxidative and anti-inflammatory properties of HT against LPS-mediated inflammation and sepsis. Therefore, HT could be applied as an alternative anti-inflammatory agent to minimize or prevent the development of systemic inflammatory response associated with septic shock.

Extra Virgin Olive Oil Polyphenols: Modulation of Cellular Pathways Related to Oxidant Species and Inflammation in Aging

The olive-oil-centered Mediterranean diet has been associated with extended life expectancy and a reduction in the risk of age-related degenerative diseases. Extra virgin olive oil (EVOO) itself has been proposed to promote a "successful aging", being able to virtually modulate all the features of the aging process, because of its great monounsaturated fatty acids content and its minor bioactive compounds, the polyphenols above all. Polyphenols are mostly antioxidant and anti-inflammatory compounds, able to modulate abnormal cellular signaling induced by pro-inflammatory stimuli and oxidative stress, as that related to NF-E2-related factor 2 (Nrf-2) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), which have been identified as important modulators of age-related disorders and aging itself. This review summarizes existing literature about the interaction between EVOO polyphenols and NF-κB and Nrf-2 signaling pathways. Reported studies show the ability of EVOO phenolics, mainly hydroxytyrosol and tyrosol, to activate Nrf-2 signaling, inducing a cellular defense response and to prevent NF-κB activation, thus suppressing the induction of a pro-inflammatory phenotype. Literature data, although not exhaustive, indicate as a whole that EVOO polyphenols may significantly help to modulate the aging process, so tightly connected to oxidative stress and chronic inflammation.