Acetyl-11-keto-β-boswellic Acid Research Articles

Boswellic acid as a potential adjunct for bone healing after endodontic surgery: In vitro study

Abstract Introduction: The role of Acetyl -11-keto-β-boswellic acid (AKBA) in regulating osteoblast differentiation was recently brought to light. Therefore, the current study was designed to explore the osteogenic differentiation capability of AKBA on bone marrow mesenchymal stem cells (BMMSCs) as a potential therapeutic agent to accelerate the healing process in apicoectomy. Materials and Methods: BMMSCs were characterized by flow cytometry. Cellular viability and proliferation assays were used with different concentrations of AKBA. Cells were divided into 5 groups to test osteogenic differentiation: Group I: negative control, Group II: positive control, Group III: BMMSCs were treated with 1 μM AKBA, Group IV: BMMSCs were treated with 0.1 μM AKBA, and Group V: BMMSCs were treated with 0.01 μM AKBA. Mineralization assays and gene expression analysis were assessed, and the significance difference between groups was established at P < 0.05. Results: The flow cytometry analysis demonstrated that BMMSCs had positive expression for mesenchymal stem cell marker and negative expression for hematopoietic markers. The concentration of 0.01 μM gave significantly higher cell density than the untreated cells after 7 days (P < 0.05). Cells treated with 0.1 and 0.01 μM AKBA revealed a significantly higher ALP activity, alizarin red, and von Kossa staining than control groups (P < 0.05). High expression of osteogenic genes was detected in BMMSCs treated with 0.1 μM AKBA (P < 0.05). Conclusions: It was declared that the concentration of 0.1 μM AKBA has no toxicity on BMMSC viability and proliferation with an impact on BMMSC osteogenic differentiation. Therefore, AKBA (0.01 μM) could be used in bone regeneration during periradicular surgery.

Antimicrobial Topical Polymeric Films Loaded with Acetyl-11-keto-β-boswellic acid (AKBA) and Silver Nanoparticles: Optimization, Characterization, and Biological Activity

The study examined the use of pure Acetyl-11-keto-β-boswellic acid (AKBA) and its derivatives as antimicrobial topical polymeric films. The concentrations of pure AKBA, boswellic acid (BA), and Silver Nanoparticles (AgNPs) of AKBA used were optimized at 0.05% (w/v) to assess the biopolymer characteristics. Carboxymethyl cellulose (CMC), sodium alginate (SA), and gelatin (Ge) composite were prepared in this study. The polymeric films were evaluated for their biological (antioxidant and antimicrobial activities) and mechanical characteristics such as tensile strength (TS) and elongation (%). Moreover, other parameters including water barrier properties and color attributes of the film were also evaluated. Furthermore, assessments were conducted using analytical techniques like FTIR, XRD, and SEM. Surface analysis revealed that AgNP precipitation led to a few particles in the film structure. Overall, the results indicate a relatively consistent microstructure. Moreover, due to the addition of AKBA and bioactive components, a significant decrease in TS, moisture content, water solubility, and water vapor permeation was observed. The films transparency also showed a decreasing trend, and the color analysis revealed decreasing yellowness (b*) of the films. Importantly, a significant increase in antioxidant activity against DPPH free radicals and ABTS cations was observed in the CSG films. Additionally, the AgNP-AKBA loaded films displayed significant antifungal activity against C. albicans. Moreover, the molecular docking analysis revealed the inter-molecular interactions between the AKBA, AgNPs, and composite films. The docking results indicate good binding of AKBA and silver nanoparticles with gelatin and cellulose molecules. In conclusion, these polymeric films have potential as novel materials with significant antioxidant and antifungal activities.

Species-Specific quantification of bioactive boswellic acids in Boswellia resin using NIR spectroscopy, HPLC and Multivariate data analysis

The bioactive compounds Acetyl-11-keto-β-boswellic acid (AKBA) and 11-keto-β-boswellic acid (KBA), found in the resin of the Boswellia tree, exhibit anti-inflammatory properties, rendering Boswellia resin an intriguing natural medicinal products. However, the content of boswellic acids varies across different Boswellia species and proper knowledge of its species-dependent nature, as well as alternatives to the resource- and time-intensive HPLC analysis, are lacking. Here we present a comprehensive investigation into the boswellic acid content of seven Boswellia species from ten countries and introduce a novel and non-destructive Near-Infrared spectroscopy method for predicting boswellic acid concentrations in solid resin samples. The HPLC-UV reference analysis revealed AKBA concentrations of up to 7.27 % (w/w) with KBA concentrations reaching up to 1.28 % (w/w). Principal Component Analysis of the HPLC and NIR spectroscopy data unveiled species-specific variations, facilitating differentiation based on boswellic acid content, characteristic chromatograms and NIR spectra. Using the HPLC-UV quantification as reference, we developed a Partial Least Squares regression model based on NIR spectra of the resin samples. This model demonstrated highly satisfactory predictive capabilities for AKBA content, achieving a root mean square error of prediction of 0.74 % (w/w) and an R2val of 0.79 in independent test set validation. Although the model was less effective for predicting KBA content, it still offered valuable estimates. The spectroscopic method introduced in this study provides a cost-effective and solvent-free approach for predicting boswellic acid content, demonstrating the potential for application in non-laboratory settings through the use of miniaturized NIR spectrometers. Consequently, this method aligns well with the principles of green chemistry and addresses the growing demand for alternative analytical techniques.

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.

Effect of Boswellic Acid on Viability of Dental Pulp Stem Cells Compared to the Commonly Used Intracanal Medications: An In Vitro Study.

This study was aimed at evaluating the effect of acetyl-11-keto-β-boswellic acid (AKBA) on dental pulp stem cells (DPSCs) viability and proliferation to be used as a potential root canal medicament. Dental pulp stem cells were isolated from human third molars. The phenotypic characterization of DPSCs was verified by flow cytometry analysis. The viability assay was performed using the methyl-thiazoltetrazolium (MTT) assay. Cells were treated with different concentration of triple antibiotic paste (TAP) and calcium hydroxide Ca(OH2) (5, 2.5, 1, 0.5, and 0.25 mg/mL), AKBA (10, 5, 1, 0.1, and 0.01 µM). All experiments were done in separate triplicate experiments. Results: Dental pulp stem cells were characterized by flow cytometry. Cells treated with Ca(OH)2 (1, 2.5, and 5 mg/mL) showed significantly reduced viability compared with the control cells (p < 0.05). Dental pulp stem cells treated with 1, 2.5, and 5 mg/mL TAP resulted in a significant decrease in viability (p < 0.05). Cells treated with AKBA in concentrations (1, 0.1, and 0.01 µM) demonstrated higher viability than the control group (p < 0.05), while AKBA in concentrations (5 and 10 µM) showed equal or decreased viability than the control group. (p > 0.05). Regarding cell density assay, AKBA showed significant increase in cell density after 5 and 7 days compared with cells medicated with TAP and Ca(OH)2 while TAP revealed marked reduction in cell density in all the tested intervals. Acetyl-11-keto-β-boswellic acid in lower concentrations (0.01, 0.1, and 1 µM) demonstrated superior cell viability than TAP and Ca(OH)2, and it may possess the potential to be an intracanal medicament in regenerative endodontics. Studying the effect of different potential root canal medicaments and their capability to induce DPSCs proliferation might be of value. The influence of AKBA on the viability and proliferation of DPSCs tested in this study sheds light on its use as a potential intracanal medication especially in regenerative endodontics. How to cite this article: Amer NA, Badawi MF, Elbeltagi MG, et al. Effect of Boswellic Acid on Viability of Dental Pulp Stem Cells Compared to the Commonly Used Intracanal Medications: An In Vitro Study. J Contemp Dent Pract 2023;24(12):957-966.

Neuro-protective Effect of Acetyl-11-keto-β-boswellic Acid in a Rat Model of Scopolamine-induced Cholinergic Dysfunction.

Acetyl-11-keto-β-boswellic acid (AKBA) is a major component of the oleo-gum resin of B. serrata with multiple pharmacological activities. The objective of this study was to explore the underlying mechanisms of neuroprotective potential of AKBA against scopolamine-mediated cholinergic dysfunction and memory deficits in rats. The rats received AKBA (2.5, 5, and 10 mg/kg, oral) for 21 days. In the third week, scopolamine was administered 30 min before the Morris water maze and passive avoidance tests. In order to perform biochemical assessments, the hippocampus and prefrontal cortex were extracted from the rats euthanized under deep anesthesia. In the MWM test, treatment with AKBA (5 and 10 mg/kg) decreased the latency and distance to find the platform. Moreover, in the PA test, AKBA remarkably increased latency to darkness and stayed time in lightness while decreasing the frequency of entry and time in the darkness. According to the biochemical assessments, AKBA decreased acetylcholinesterase activity and malondialdehyde levels while increasing antioxidant enzymes and total thiol content. Furthermore, AKBA administration restored the hippocampal mRNA and protein levels of brain-derived neurotrophic factor (BDNF) and mRNA expression of B-cell lymphoma (Bcl)- 2 and Bcl-2- associated X genes in brain tissue of scopolamine-injured rats. The results suggested the effectiveness of AKBA in preventing learning and memory dysfunction induced by scopolamine. Accordingly, these protective effects might be produced by modulating BDNF, cholinergic system function, oxidative stress, and apoptotic markers.

Acetyl-11-Keto-β-Boswellic Acid Accelerates the Repair of Spinal Cord Injury in Rats by Resisting Neuronal Pyroptosis with Nrf2.

The primary aim of this study is to delve into the potential of Acetyl-11-keto-β-boswellic acid (AKBA) in ameliorating neuronal damage induced by acute spinal cord injury, as well as to unravel the intricate underlying mechanisms. A cohort of 40 Sprague-Dawley rats was meticulously categorized into four groups. Following a seven-day oral administration of AKBA, damaged spinal cord samples were meticulously procured for Nissl staining and electron microscopy to assess neuronal demise. Employing ELISA, immunofluorescence, Western blot (WB), and quantitative polymerase chain reaction (qPCR), the modulatory effects of AKBA within the context of spinal cord injury were comprehensively evaluated. Furthermore, employing an ex vivo extraction of spinal cord neurons, an ATP + LPS-induced pyroptotic injury model was established. The model was subsequently subjected to Nrf2 inhibition, followed by a battery of assessments involving ELISA, DCFH-DA staining, flow cytometry, immunofluorescence, and WB to decipher the effects of AKBA on the spinal cord neuron pyroptosis model. By engaging the Nrf2-ROS-NLRP3 pathway, AKBA exerted a repressive influence on the expression of the pyroptotic initiator protein Caspase-1, thereby mitigating the release of GSDMD and alleviating pyroptosis. Additionally, AKBA demonstrated the ability to attenuate the release of IL-18 and IL-1β, curbing neuronal loss and expediting the restorative processes within the context of spinal cord injury. Our study elucidates that AKBA can reduce spinal cord neuronal apoptosis, providing a basis for the development of AKBA as a clinical treatment for spinal cord injury.

AKBA alleviates experimental pancreatitis by inhibiting oxidative stress in Macrophages through the Nrf2/HO-1 pathway.

Acute pancreatitis (AP) is an inflammatory condition of the pancreas characterized by oxidative stress and inflammation in its pathophysiology. Acetyl-11-keto-β-boswellic acid (AKBA) is an active triterpenoid with antioxidant activity. This article seeks to assess the impact of AKBA on AP and investigate its underlying mechanisms. AP was induced in wild-type, Lyz2+/cre Nrf2fl/fl mice and Pdx1+/cre Nrf2fl/fl mice by caerulein. Serum amylase and lipase levels, along with histological grading, were utilized to evaluate the severity of AP. Murine bone marrow-derived macrophages (BMDMs) were isolated, cultured, and polarized to the M1 subtype. Flow cytometry and ELISA were utilized to identify the macrophage phenotype. Alterations in oxidative stress damage and intracellular ROS were observed. Nrf2/HO-1 signaling pathways were also evaluated. In a caerulein-induced mouse model of AP, treatment with AKBA reduced blood amylase and lipase activity and ameliorated pancreatic tissue histological and pathological features. Furthermore, AKBA significantly mitigated oxidative stress-induced damage and induced the expression of Nrf2 and HO-1 protein. Additionally, by using conditional knockout mice (Lyz2+/cre Nrf2fl/fl and Pdx1+/cre Nrf2fl/fl mice), we verified that Nrf2 primarily functions in macrophages rather than acinar cells. In vitro, AKBA inhibits pro-inflammatory M1-subtype macrophage polarization and reduces ROS generation through Nrf2/HO-1 oxidative stress pathway. Moreover, the protective effects of AKBA against AP were abolished in myeloid-specific Nrf2-deficient mice and BMDMs. Molecular docking results revealed interactions between AKBA and Nrf2. Our results confirm that AKBA exerts protective effects against AP in mice by inhibiting oxidative stress in macrophages through the Nrf2/HO-1 Pathway.

Antiproliferative and cell cycle arrest potentials of 3-O-acetyl-11-keto-β-boswellic acid against MCF-7 cells in vitro

IntroductionCancer is a major issue in medical science with increasing death cases every year worldwide. Therefore, searching for alternatives and nonorthodox methods of treatments with high efficiency, selectivity and less toxicity is the main goal in fighting cancer. Acetyl-11-keto-β-boswellic acid (AKBA), is a derivative pentacyclic triterpenoid that exhibited various biological activities with potential anti-tumoral agents. In this research, AKBA was utilized to examine the potential cytotoxic activity against MCF-7 cells in vitro and monitor the cellular and morphological changes with a prospective impact on apoptosis induction. MethodsThe cytotoxic activity of AKBA was measured by 3(4,5dimethylthiazole- 2-yl)-2,5 diphyneltetrazolium bromide (MTT) assay. A dose-dependent inhibition in MCF-7 cell viability was detected. The clonogenicity of MCF-7 cells was significantly suppressed by AKBA increment in comparison with untreated cells. ResultMorphologically, exposure of MCF-7 cells to high AKBA concentrations caused changes in cell nuclear morphology which was indicated by increasing in nuclear size and cell permeability intensity. The mitochondrial membrane potential (ΔΨm) was reduced by increasing AKBA concentration with a significant release of cytochrome c. Acridine orange/ethidium bromide dual staining experiment confirmed that MCF-7 cells treated with AKBA (IC50 concentration) displayed a late stage of apoptosis indicated by intense and bright reddish colour. ConclusionA significant increase in reactive oxygen species formation was observed. Caspase 8 and caspase 9 activities were estimated and AKBA activated the production of caspase 8 and caspase 9 in a dose-dependent pattern. Finally, the cell phase distribution analysis was conducted, and flow cytometric analysis showed that AKBA at 200 μg mL-1 significantly arrest MCF-7 cells at the G1 phase and triggered apoptosis.

Boswellia: Systematically scoping the in vitro, in vivo and clinical research

Boswellia is a genus of shrubs or small/medium trees in which there is continued interest in potential medical use of a number of species. This review aimed to produce a ‘map’ of research on Boswellia to identify potential for translation of research findings across different areas and any research gaps. Searches were carried out using major databases for in vitro, in vivo and clinical studies on any condition or disease, involving Boswellia species and extracts. Data were extracted on the health condition or disease, study type, Boswellia species and form being investigated. 5296 records were retrieved resulting in 657 relevant research papers; 297 (45.2%) reported in vitro studies, 236 (40.0%) reported in vivo studies, and 68 (10.3%) reported clinical studies . Studies were located corresponding to 20 of 22 health research categories, the most frequently researched being Cancer and Neoplasms, Inflammatory and Immune System, and Infection. The species Boswellia serrata and Boswellia sacra have undergone most investigation. Different forms of Boswellia were employed with boswellic acids, specifically Acetyl-11-keto-β-Boswellic acid (AKBA) and 11-Keto-β-Boswellic acid (KBA) generating most interest. Significant numbers of animal studies were located but few clinical studies. The extent, range and nature of the research on extracts and products derived from Boswellia species is revealed. Research is highlighted which may have more widely applicable results (for example on pharmacokinetics, delivery and toxicity), as are current research gaps and potential targets for greater collation of existing data to reduce duplication.

Acetyl-11-keto-β-boswellic acid improves clinical symptoms through modulation of Nrf2 and NF-κB pathways in SJL/J mouse model of experimental autoimmune encephalomyelitis

Multiple sclerosis (MS) is characterized by chronic autoimmune inflammation of central nervous system (CNS), i.e. brain and spinal cord. Autoimmune inflammation of the CNS and periphery causes demyelination of axons ultimately leading to clinical symptoms such as gait imbalance, lack of coordination and paraplegia. Innate immune cells such as dendritic cells and neutrophils play a critical role in the initiation and progression of MS through upregulation of oxidants. Two prominent pathways that play important role in regulation of oxidant-antioxidant balance are nuclear factor-erythroid factor 2-related factor 2(Nrf2) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). Nrf2-mediated upregulation of antioxidants counteracts NF-κB-mediated oxidant generation. Therefore, this study evaluated the effects of nutraceutical drug, acetyl-11-keto-β-boswellic acid (AKBA) in relapsing remitting model of experimental autoimmune encephelomyelitis (EAE). Efficacy of AKBA was explored on clinical symptoms, Nrf2, hemeoxygenase-1 (HO-1), NF-κB, inducible nitric oxide synthase (iNOS) in CNS and periphery of SJL/J mice. Our results show that expression of p-NF-κB and iNOS is elevated, whereas expression of Nrf2 and HO-1 is decreased in CD11c + DCs and CNS, which is linked with appearance of clinical symptoms in immunized SJL/J mice. Treatment of immunized SJL/J mice with AKBA causes improvement of clinical symptoms and downregulation of inflammatory markers in CD11c + DCs (p-NF-κB, iNOS, and nitrotyrosine), and CNS (p-NF-κB, iNOS, nitrotyrosine,lipid peroxides, and total antioxidant capacity). Treatment of immunized SJL/J mice with AKBA also causes rectification of Nrf2 signaling in CD11c + DCs, and CNS. These results propose AKBA ameliorates EAE disease progression through rectification of Nrf2 signaling and attenuation of NF-κB pathway in RR model of EAE. Therefore, nutraceutical compound, AKBA may be therapeutically useful in RRMS.

Synthesis of 3-O-Acetyl-11-keto-β-boswellic Acid (AKBA)-Derived Amides and Their Mitochondria-Targeted Antitumor Activities

In this study, we synthesized a series of amide and mitochondria-targeted derivatives with 3-O-acetyl-11-keto-β-boswellic acid (AKBA) as the parent structure and an ethylenediamine moiety as the link chain. Compound 5e, a mitochondrial-targeting potential derivative, showed significantly stronger antitumor activity than that of AKBA, and it could induce vacuolization of A549 cells and stimulate the production of reactive oxygen species (ROS) in a time- and concentration-dependent manner. The antioxidant N-acetylcysteine (NAC) could inhibit the ROS level but could not suppress vacuolization and cell death induced by 5e. Further studies demonstrated that 5e caused abnormal opening of mitochondrial permeability transition pore (MPTP) and a decrease of mitochondrial membrane potential; additionally, it caused cell cycle arrest in G0/G1 but did not induce apoptosis. 5e represented a compound with improved antiproliferative effects for cancer therapy working through new mechanisms.

The protective effect of Boswellic acid and Ellagic acid loaded, colon targeted, and pH-sensitive N-succinyl chitosan in ulcerative colitis rat model

Targeted drug delivery systems that provide therapeutic activity with lower concentrations of both herbal and other substances, while reducing access to non-target sites and undesirable effects; have an important potential for future projections in terms of pharmacological and toxicological studies. The present study aimed to investigate the protective effects of Acetyl 11-keto-β-boswellic acid (AKBA) and Ellagic acid (EA) loaded, colon targeted, and pH-Sensitive N-succinyl chitosans (NsCh) in ulcerative colitis (UC) model induced by acetic acid (AA) in rats. The physicochemical characterization (elemental analysis, FT-IR, DSC, XRD, SEM, NMR) analyses, swelling, and releasing tests of NsCh's suggested that AKBA and EA were successfully loaded to pH-sensitive polymer and targeted to the colon. The targeted AKBA and EA were administered to Wistar rats (n:30, 5 groups) and damage, inflammatory cytokine, protein expression, oxidative stress, and antioxidant parameter levels in colon tissues of the groups were determined. Increase in the levels of CAT, GPx activities, and decrease in necrosis, inflammation, and levels of MDA, TNF-α, COX-2, NF-kB were observed in the targeted EA and AKBA groups compared to the UC group. The potential protective effect of EA and AKBA loaded, colon-targeted, pH-sensitive controlled releasing system against UC and the potential to be licensed preparations by completing the next stages of in vitro and in vivo studies were demonstrated.

Binding of boswellic acids to functional proteins of the SARS-CoV-2 virus: Bioinformatic studies.

Boswellic acids (BAs) have been shown to possess antiviral activity. Using bioinformatic methods, it was tested whether or not acetyl‐11‐keto‐β‐boswellic acid (AKBA), 11‐keto‐β‐boswellic acid (KBA), β‐boswellic acid (BBA), and the phosphorylated active metabolite of Remdesivir® (RGS‐P3) bind to functional proteins of SARS‐CoV‐2, that is, the replicase polyprotein P0DTD1, the spike glycoprotein P0DTC2, and the nucleoprotein P0DTC9. Using P0DTD1, AKBA and KBA showed micromolar binding affinity to the RNA‐dependent RNA polymerase (RdRp) and to the main proteinase complex Mpro. Phosphorylated BAs even bond in the nanomolar range. Due to their positive and negative charges, BAs and RGS‐P3 bond to corresponding negative and positive areas of the protein. BAs and RGS‐P3 docked in the tunnel‐like cavity of RdRp. BAs also docked into the elongated surface rim of viral Mpro. In both cases, binding occurred with active site amino acids in the lower micromolecular to upper nanomolar range. KBA, BBA, and RGS‐P3 also bond to P0DTC2 and P0DTC9. The binding energies for BAs were in the range of −5.8 to −6.3 kcal/mol. RGS‐P3 and BAs occluded the centrally located pore of the donut‐like protein structure of P0DTC9 and, in the case of P0DTC2, RGS‐P3 and BAs impacted the double‐wing‐like protein structure. The data of this bioinformatics study clearly show that BAs bind to three functional proteins of the SARS‐CoV‐2 virus responsible for adhesion and replication, as does RGS‐P3, a drug on the market to treat this disease. The binding effectiveness of BAs can be increased through phosphate esterification. Whether or not BAs are druggable against the SARS‐CoV‐2 disease remains to be established.

Inhibitory effect of acetyl-11-keto-β-boswellic acid on titanium particle-induced bone loss by abrogating osteoclast formation and downregulating the ERK signaling pathway

Wear debris-induced osteoclast accumulation around implants plays a crucial role during the progression of periprosthetic osteolysis (PPO). We have confirmed that acetyl-11-keto-β-boswellic acid (AKBA) promotes bone formation and protects against particle-induced bone destruction in vivo. However, the effect of AKBA on titanium-induced bone resorption is unknown. In this study, we detected the inhibitory effect of AKBA on titanium-induced bone erosion in vivo and used RAW264.7 cells and bone marrow macrophages (BMMs) to investigate the effect and underlying mechanism of AKBA on the differentiation and resorptive function of osteoclasts. Our findings revealed that AKBA inhibited particle-induced bone loss and osteoclast formation in vivo. Furthermore, AKBA exerted inhibitory effects on RANKL-induced osteoclastogenesis, osteoclastic ring-dependent resorption and the expression of osteoclast marker genes via the ERK signaling pathway in vitro. Our data further established the protective effect of AKBA on titanium particle-induced bone erosion from a new perspective of bone erosion prevention, strongly confirming that AKBA is an appropriate agent for protection against PPO.

Role of Testosterone Levels on the Combinatorial Effect of Boswellia serrata Extract and Enzalutamide on Androgen Dependent LNCaP Cells and in Patient Derived Cells.

Co-therapy with herbal extracts along with current clinical drugs is being increasingly recognized as a useful complementary treatment for cancer. The anti-cancer property of the phyto-derivative acetyl-11 keto β boswellic acid (AKBA) has been studied in many cancers, including prostate cancer. However, the whole extract of the gum resin Boswellia serrata (BS) and anti-androgen enzalutamide has not been explored in prostate cancer to date. We hypothesized that the BS extract containing 30% (AKBA) with enzalutamide acted synergistically in the early phase of cancer, especially in LNCaP cells, by inhibiting androgen receptor (AR) and by reducing cell proliferation, and further, that the extract would be superior to the action of the active ingredient AKBA when used alone or in combination with enzalutamide. To test our hypothesis, we treated LNCaP cells with BS extract or AKBA and enzalutamide both individually and in combination to analyze cell viability under different levels of dihydrotestosterone (DHT). The inhibition of androgen receptor (AR) followed by the expression of prostate-specific antigen (PSA) and the efflux mechanism of the cells were analyzed to determine the effect of the combination on the cellular mechanism. Cells derived from prostate cancer patients were also tested with the combination. Only 6 µM enzalutamide along with BS in the range of 4.1 µg/ml to 16.4 µg/ml gave the best synergistic results with nearly 50% cell killing even though standard enzalutamide doses were as high as 48 µM. Cell killing was most effective at intermediate DHT concentrations of approximately 1 nM, which corresponds to normal physiological serum levels of DHT. The Pgp expression level and the androgen receptor expression levels were reduced under the combination treatment; the former helping to minimize drug efflux and the latter by reducing the sensitivity to hormonal changes. Furthermore, the combination reduced the PSA level secreted by the cells. In contrast, AKBA could not achieve the needed synergism for adequate cell killing at equivalent concentrations. The combination of enzalutamide and BS extract containing 30% AKBA because of their synergistic interaction is an attractive therapeutic option for treating early stage (hormone-dependent) prostate cancer and is superior to the use of AKBA alone.

Acetyl-11-Keto-β-Boswellic Acid Restrains Inflammation and Extracellular Matrix Degradation of Osteoarthritis via Suppression of NF-κB Pathway

Background: Mechanical stress along with inflammation play causative roles in the development of osteoarthritis (OA), which decreases the quality of life and causes economic loss. Inflammation and extracellular matrix (ECM) degradation have been identified as key factors in the development of OA. As the main active component in frankincense, acetyl-11-keto-β-boswellic acid (AKBA) has been shown to have positive effects on inflammation. However, the effects of AKBA in cartilage inflammation and ECM degradation are currently elusive. Methods: Micro-CT, Histologic analysis, and Immunohistochemical (IHC) analysis were conducted in vivo on Hulth-Telhag OA rat with or without AKBA treatment. The effects of AKBA on inflammation and ECM degradation of rat articular chondrocytes were evaluated by CCK-8, Western Blot, quantitative real-time polymerase chain reaction (qRT-PCR), and immunofluorescence (IF) assay. We demonstrated the role of inflammation and ECM degradation in the pathogenesis of OA and determined the protective effect of AKBA on both Hulth-Telhag rat OA model and lipopolysaccharide (LPS)-induced rat chondrocytes. Findings: We found increased inflammatory expression and decreased ECM expression in OA model cartilage and LPS-induced chondrocytes. Meanwhile, the protective effect of AKBA and its inhibitory effects on inflammation as well as ECM-related markers were also observed in the rat Hulth-Telhag model. Furthermore, activation of NF-κB attenuated nuclear p65 protein levels in chondrocytes upon LPS stimulation. In addition, AKBA was found to subsequently reversed the LPS-induced activation of NF- κB signal and inflammation-related ECM degradation in chondrocytes. Interpretation: Suppression of NF-κB pathway activation by AKBA restrains OA development via inhibition of inflammation and ECM degradation. AKBA is a promising therapeutic agent for the treatment of OA. Funding Information: Financial supports from National Natural Science Foundation of China (Nos. 82072425, 81873991 and 81672238), the Natural Science Foundation of Jiangsu Province (Nos. BK20180001), Jiangsu Commission of Health (No. H2018027); the Young Medical Talents of Jiangsu Province (No. QNRC2016751), Suzhou Jiangsu Commission of Health (No. SYS2019100 and SYS2019101), Suzhou Science and Technology Foundation (No. SYSD2017170, SYSD2018207 and SS201805), Project of Suzhou Sports Research Bureau (No. TY2019-204), and Special Project of Diagnosis and Treatment Technology for Key Clinical Diseases in Suzhou (LCZX202003). Declaration of Interests: There are no declarations of interest. Ethics Approval Statement: Animal welfare and experimental procedures were carried out in accordance with the Declaration of Helsinki, and were approved by the Ethics Committee of the First Affiliated Hospital of Soochow University.

The Beneficial Effect of Boswellic Acid on Bone Metabolism and Possible Mechanisms of Action in Experimental Osteoporosis.

Estrogen is instrumental in the pathological process of osteoporosis because a deficiency of this hormone increases the release of bone-resorbing cytokines. Acetyl-11-keto-β-boswellic acid (AKBA), a constituent from Boswellia serrata, has an anti-inflammatory effect by inhibiting tumor necrosis factor-α (TNF-α) expression, which leads to a decline in receptor activator of nuclear factor-kappa B (NF-κB) ligand, and consequently, a reduction in osteoclast activity. Hence, AKBA may be beneficial against bone loss during osteoporosis. Therefore, the current study intended to evaluate the beneficial effects of AKBA in ovariectomy-induced osteoporosis and to investigate its mechanism of action. Sham-operation or ovariectomy female Sprague Dawley rats were used for evaluating the antiosteoporotic effect of AKBA in this study. AKBA (35 mg/kg, p.o.) and estradiol (0.05 mg/kg, i.m.) were administered for 42 days. At the end of the experiment, body and uterus weights, serum and urine calcium and phosphorus, serum alkaline phosphatase, and urinary creatinine levels, besides serum levels of NF-κB and TNF-α were determined. Weight, length, thickness, hardness, calcium content, as well as the bone mineral density of femur bone and lumbar vertebra were measured. A histopathological examination was also carried out. AKBA ameliorated all tested parameters and restored a normal histological structure. Thus, AKBA showed good antiosteoporotic activity, which may be mediated through its suppression of the NF-κB-induced TNF-α signaling pathway.

Acetyl-11-keto-β-boswellic acid inhibits proliferation and induces apoptosis of gastric cancer cells through the phosphatase and tensin homolog /Akt/ cyclooxygenase-2 signaling pathway.

BACKGROUNDGastric cancer is one of the most common malignant tumors of the digestive system worldwide, posing a serious danger to human health. Cyclooxygenase (COX)-2 plays an important role in the carcinogenesis and progression of gastric cancer. Acetyl-11-keto-β-boswellic acid (AKBA) is a promising drug for cancer therapy, but its effects and mechanism of action on human gastric cancer remain unclear.AIMTo evaluate whether the phosphatase and tensin homolog (PTEN)/Akt/COX-2 signaling pathway is involved in the anti-tumor effect of AKBA in gastric cancer.METHODSHuman poorly differentiated BGC823 and moderately differentiated SGC7901 gastric cancer cells were routinely cultured in Roswell Park Memorial Institute 1640 medium supplemented with 10% fetal bovine serum and 1% penicillin/streptomycin. Gastric cancer cell proliferation was determined by methyl thiazolyl tetrazolium colorimetric assay. Apoptosis was measured by flow cytometry. Cell migration was assessed using the wound-healing assay. Expression of Bcl-2, Bax, proliferating cell nuclear antigen, PTEN, p-Akt, and COX-2 were detected by Western blot analysis. A xenograft nude mouse model of human gastric cancer was established to evaluate the anti-cancer effect of AKBA in vivo.RESULTSAKBA significantly inhibited the proliferation of gastric cancer cells in a dose- and time-dependent manner, inhibited migration in a time-dependent manner, and induced apoptosis in a dose-dependent manner in vitro; it also inhibited tumor growth in vivo. AKBA up-regulated the expression of PTEN and Bax, and down-regulated the expression of proliferating cell nuclear antigen, Bcl-2, p-Akt, and COX-2 in a dose-dependent manner. The PTEN inhibitor bpv (Hopic) reversed the high expression of PTEN and low expression of p-Akt and COX-2 that were induced by AKBA. The Akt inhibitor MK2206 combined with AKBA down- regulated the expression of p-Akt and COX-2, and the combined effect was better than that of AKBA alone.CONCLUSIONAKBA inhibits the proliferation and migration and promotes the apoptosis of gastric cancer cells through the PTEN/Akt/COX-2 signaling pathway.

Acetyl-11-keto-β-boswellic acid prevents testicular torsion/detorsion injury in rats by modulating 5-LOX/LTB4 and p38-MAPK/JNK/Bax/Caspase-3 pathways

AimsTesticular torsion/detorsion (T/D) is a critical medical condition that necessitates prompt surgical intervention to avoid testicular atrophy and infertility. The use of natural compounds may protect against the associated detrimental oxidative stress and inflammatory responses. Interestingly, acetyl-11-keto-β-boswellic acid (AKBA), the main active constituent of Boswellia resin, has shown potent inhibitory effect on 5-lipoxygenase enzyme which converts arachidonic acid into inflammatory mediators. Therefore, this study was conducted to assess the protective mechanisms by which AKBA may protect against testicular T/D injury in rats. Main methodsMale rats were randomly distributed into five groups: Sham, AKBA (50 mg/kg, p.o.), unilateral testicular T/D, AKBA at two dose levels (25 or 50 mg/kg for 15 successive days) followed by T/D. Histological examination and Johnsen's score were performed to assess testicular injury and perturbations in spermatogenesis. Biochemical parameters included markers of testicular function (serum testosterone), oxidant/antioxidant status (malondialdehyde, glutathione), inflammation (5-lipoxygenase, leukotriene-B4, myeloperoxidase, interleukin-1β, interleukin-6), apoptosis (Bax, Bcl2, caspase-3), DNA integrity (quantitative DNA fragmentation, DNA laddering, PARP-1), energy production (ATP), in addition to p38 MAPK and JNK protein expression. Key findingsIn a dose dependent manner, AKBA significantly inhibited testicular T/D-induced upregulation of 5-LOX/LTB4 and p38-MAPK/JNK/Bax pathways and their associated downstream inflammatory and apoptotic cascades. These effects were accompanied with ATP replenishment and DNA preservation, resulting ultimately in salvage of the testis. SignificanceUnprecedentedly, the present mechanistic study revealed the pathways by which AKBA may inhibit testicular T/D injury and offered a novel protective approach that may attenuate the severity of this condition.