Analogues of boswellic acids as inhibitors of pro-inflammatory cytokines TNF-α and IL-6

Effectiveness of gellan gum scaffolds loaded with Boswellia serrata extract for in-situ modulation of pro-inflammatory pathways affecting cartilage healing

In this study, we developed a composite hydrogel based on Gellan gum containing Boswellia serrata extract (BSE). BSE was either incorporated directly or loaded into an MgAl-layered double hydroxide (LDH) clay to create a multifunctional cartilage substitute. This composite was designed to provide anti-inflammatory properties while enhancing chondrogenesis. Additionally, LDH was exploited to facilitate the loading of hydrophobic BSE components and to improve the hydrogel's mechanical properties. A calcination process was also adopted on LDH to increase BSE loading. Physicochemical and mechanical characterizations were performed by spectroscopic (XPS and FTIR), thermogravimetric, rheological, compression test, weight loss and morphological (SEM) investigations. RPLC-ESI-FTMS was employed to investigate the boswellic acids release in simulated synovial fluid. The composites were cytocompatible and capable of supporting the mesenchymal stem cells (hMSC) growth in a 3D-conformation. Loading BSE resulted in the modulation of the pro-inflammatory cascade by down-regulating COX2, PGE2 and IL1β. Chondrogenesis studies demonstrated an enhanced differentiation, leading to the up-regulation of COL 2 and ACAN. This effect was attributed to the efficacy of BSE in reducing the inflammation through PGE2 down-regulation and IL10 up-regulation. Proteomics studies confirmed gene expression findings by revealing an anti-inflammatory protein signature during chondrogenesis of the cells cultivated onto loaded specimens. Concluding, BSE-loaded composites hold promise as a tool for the in-situ modulation of the inflammatory cascade while preserving cartilage healing.

Anti-inflammatory and anti-arthritic potential of methotrexate in combination with BA-25, an amino analogue of β-boswellic acid in the treatment of rheumatoid arthritis

β- boswellic acid, a pentacyclic triterpene derived from Boswellia serrata is extensively known for its anti-inflammatory potential. BA-25 (3-α-o-acetoxy-4β-amino-11-oxo-24-norurs-12-ene) is an amino analogue of β-boswellic acid that has shown anti-inflammatory potential in LPS-induced macrophages and animal models. The present study aims at investigation of the combination of BA-25 with the conventional gold standard DMARD methotrexate (MTX) for its anti-inflammatory and anti-arthritic potential using in vitro and in vivo experimental models. The anti-inflammatory potential of MTX versus the combination (BA-25 + MTX) was investigated for inhibition of NO, ROS and pro-inflammatory cytokines including TNF-α and IL-6 using ELISA in LPS-stimulated RAW-264.7 cells. The results demonstrated significant reduction in NO, ROS, TNF- α and IL-6 production with the combination treatment in comparison to MTX alone. The cytokine inhibition potential of the combination was further validated in-vivo using balb/c wherein the combination restored LPS-induced increase in pro-inflammatory cytokines. The toxicological aspect of the in vivo doses of the combination was also investigated in mice after dosing for 28 days wherein the results suggested no significant change in the hematological parameters and serum biochemical parameters in the combination versus the vehicle group. The effect of BA-25 was also investigated on MTX-induced increase in liver function tests and the expression of Bax and blc2. The results demonstrated decrease in the production of liver enzymes with BA-25 administration along with downregulating the expression of apoptotic protein Bax while increasing the expression of anti-apoptotic protein Bcl2. Furthermore, pharmacokinetic studies of BA-25 were conducted in Balb/c mice wherein the compound showed rapid absorption, high volume of distribution and a t1/2 of 13.08. Finally the anti-arthritic effect of the combination of MTX + BA-25 vs MTX alone was investigated using CIA model in DBA/1 mice wherein the treatment with the combination resulted in significant reduction in paw inflammation, IL-6 and IL-1β levels. Furthermore, the western blot analysis demonstrated considerable decrease in the expression of p-NF-κB p65 and p-IκB in the ankle-joint tissue of the CIA mice treated with the combination therapy. The results insinuated increased anti-inflammatory and anti-arthritic potential of the combination of MTX with BA-25 as evident from in to vitro and in-vivo studies.

Immunomodulatory properties of triterpenes

The immune system is one of the main defence mechanisms of the human body. Inadequacy of this system or immunodeficiency results in increased risk of infections and tumours, whereas over-activation of the immune system causes allergic or autoimmune disorders. A well-balanced immune system is important for protection and for alleviation of these diseases. There is a growing interest to maintain a well-balanced immune system, especially after the Covid-19 pandemic. Many biological extracts, as well as natural products, have become popular due to their wide array of immunomodulatory effects and influence on the immune system. Triterpenes, one of the secondary metabolite groups of medicinal plants, exhibit immunomodulatory properties by various mechanisms. Different triterpenes, including components of commonly consumed plants, can promote some protection and alleviation of disease symptoms linked with immune responses and thus enhance overall well-being. This review aims to highlight the efficacy of triterpenes in light of the available literature evidence regarding the immunomodulatory properties of triterpenes. We have reviewed widely investigated immunomodulatory triterpenes; oleanolic acid, glycyrrhizin, glycyrrhetinic acid, pristimerin, ursolic acid, boswellic acid, celastrol, lupeol, betulin, betulinic acid, ganoderic acid, cucumarioside, and astragalosides which have important immunoregulatory properties. In spite of many preclinical and clinical trials were conducted on triterpenes related to their immunoregulatory actions, current studies have several limitations. Therefore, especially more clinical studies with optimal design is essential.

Ameliorative Effects of Boswellic Acid on Fipronil-Induced Toxicity: Antioxidant State, Apoptotic Markers, and Testicular Steroidogenic Expression in Male Rats

The study investigated the ability of boswellic acid (BA) to alleviate the testicular and oxidative injury FPN insecticide intoxication in the male rat model. Rats were randomly assigned to six equivalent groups (six rats each) as the following: control rats orally administered with 2 mL physiological saline/kg of body weight (bwt); boswellic acid (BA1) rats orally administered 250 mg BA/kg bwt; boswellic acid (BA2) rats orally administered 500 mg BA/kg bwt; fipronil (FPN) rats orally administered 20 mg FPN/kg bwt; (FPN + BA1) rats orally administered 20 mg FPN/kg bwt plus 250 mg BA/kg bwt, and (FPN + BA2) rats orally administered 20 mg FPN/kg bwt plus 500 mg BA/kg bwt. After 60 days, semen viability percentage and live spermatozoa percentage were decreased, and a considerably increased abnormality of the sperm cells in FPN-administered rats improved substantially with the co-administration of BA. BA had refinement of the histological architecture of testes and sexual glands. Quantitative analysis recorded a noticeable decline in the nuclear cell-proliferating antigen (PCNA) percentage area. FPN triggered cell damage, which was suggested by elevated malondialdehyde and interleukin 6, tumor necrosis factors alpha, and decreased glutathione level. Proapoptotic factor overexpression is mediated by FPN administration, while it decreased the antiapoptotic protein expression. Similarly, BA has shown significant upregulation in steroidogenic and fertility-related gene expression concerning the FPN group. Pathophysiological damages induced by FPN could be alleviated by BA's antioxidant ability and antiapoptotic factor alongside the upregulation of steroidogenic and fertility-related genes and regimented the detrimental effects of FPN on antioxidant and pro-inflammatory biomarkers.

Protective Effect of Casperome®, an Orally Bioavailable Frankincense Extract, on Lipopolysaccharide- Induced Systemic Inflammation in Mice

Introduction: Despite recent advances in critical care, sepsis remains a crucial cause of morbidity and mortality in intensive care units. Therefore, the identification of new therapeutic strategies is of great importance. Since ancient times, frankincense is used in traditional medicine for the treatment of chronic inflammatory disorders such as rheumatoid arthritis. Thus, the present study intends to evaluate if Casperome^® (Casp), an orally bioavailable soy lecithin-based formulation of standardized frankincense extract, is able to ameliorate systemic effects and organ damages induced by severe systemic inflammation using a murine model of sepsis, i.e., intraperitoneal administration of lipopolysaccharides (LPS). Methods: Male 60-day-old mice were assigned to six treatment groups: (1) control, (2) LPS, (3) soy lecithin (blank lecithin without frankincense extract), (4) Casp, (5) soy lecithin plus LPS, or (6) Casp plus LPS. Soy lecithin and Casp were given 3 h prior to LPS treatment; 24 h after LPS administration, animals were sacrificed and health status and serum cytokine levels were evaluated. Additionally, parameters representing liver damage or liver function and indicating oxidative stress in different organs were determined. Furthermore, markers for apoptosis and immune cell redistribution were assessed by immunohistochemistry in liver and spleen. Results: LPS treatment caused a decrease in body temperature, blood glucose levels, liver glycogen content, and biotransformation capacity along with an increase in serum cytokine levels and oxidative stress in various organs. Additionally, apoptotic processes were increased in spleen besides a pronounced immune cell infiltration in both liver and spleen. Pretreatment with Casp significantly improved health status, blood glucose values, and body temperature of the animals, while serum levels of pro-inflammatory cytokines and oxidative stress in all organs tested were significantly diminished. Finally, apoptotic processes in spleen, liver glycogen loss, and immune cell infiltration in liver and spleen were distinctly reduced. Casp also appears to induce various cytochromeP450 isoforms, thus causing re-establishment of liver biotransformation capacity in LPS-treated mice. Conclusion: Casp displayed anti-inflammatory, anti-oxidative, and hepatoprotective effects. Thus, orally bioavailable frankincense extracts may serve as a new supportive treatment option in acute systemic inflammation and accompanied liver dysfunction.

Application of the Curtius rearrangement to the synthesis of 1′-aminoferrocene-1-carboxylic acid derivatives

The shortest synthesis of N-protected 1′-aminoferrocene-1-carboxylic acid from readily available ferrocene-1,1′-dicarboxylic acid is reported.

Modulation of Inflammatory Response to Implanted Biomaterials Using Natural Compounds

Tissue engineering offers a promising strategy to restore injuries resulting from trauma, infection, tumor resection, or other diseases. In spite of significant progress, the field faces a significant bottleneck; the critical need to understand and exploit the interdependencies of tissue healing, angiogenesis, and inflammation. Inherently, the balance of these interacting processes is affected by a number of injury site conditions that represent a departure from physiological environment, including reduced pH, increased concentration of free radicals, hypoglycemia, and hypoxia. Efforts to harness the potential of immune response as a therapeutic strategy to promote tissue repair have led to identification of natural compounds with significant anti-inflammatory properties. This article provides a concise review of the body's inflammatory response to biomaterials and describes the role of oxygen as a physiological cue in this process. We proceed to highlight the potential of natural compounds to mediate inflammatory response and improve host-graft integration. Herein, we discuss the use of natural compounds to map signaling molecules and checkpoints that regulate the cross-linkage of immune response and skeletal repair.