Development and optimisation of 3-Acetyl-11-keto-β-boswellic acid loaded poly-lactic-co-glycolic acid-nanoparticles with enhanced oral bioavailability and in-vivo anti-inflammatory activity in rats

Determination of 3-acetyl-11-keto-β-boswellic acid in analytical and biological samples using streamlined and robust RP-HPLC method

AKBA (3-acetyl-11-keto-β-boswellic acid) is a phytoconstituent derived from Boswellia serrata extract and utilized in the management of rheumatoid arthritis. Drug delivery approaches showed interest in delivering AKBA with advanced nanotechnology. There is a need for a simple, sensitive, and robust HPLC method that can determine AKBA in complex nanoformulation and in vitro and ex vivo samples. In the proposed work, the RP-HPLC method was developed using a mobile phase comprising a mixture of acetonitrile : milli Q (90 : 10) at detection λmax 250 nm. The method exhibited a linearity of 250 to 20 000 ng mL-1 with a high correlation coefficient of 1. The limit of detection and limit of quantification for the analytes were found to be 41.32 ng mL-1 and 125.21 ng mL-1, respectively. In the accuracy study, the % recovery of AKBA was found to be 98% to 102%, and the precision study showed less than 2% relative standard deviation. The developed method was found to be robust under chromatographic conditions with changes in pH and mobile phase mixture ratio. The method was also explored for forced degradation study, and the results showed the successful separation of degradation products from the AKBA. Further, the RP-HPLC method was applied for the quantification of AKBA in topical nanoformulations and different matrices, such as skin matrices and adhesive tapes. The method was able to measure entrapment efficiency (93.13 ± 1.94%), drug loading (25.83 ± 0.54%), drug assay in a gel matrix (96.99 ± 3.89%), drug amount in stratum corneum (7.90 ± 0.62 μg cm-2), and drug amount in viable skin layers (33.94 ± 0.21 μg cm-2) with high-speed reproducibility. The developed method can be utilized for the routine analysis of AKBA in conventional and complex formulations in academia and industry.

Efficacy evaluation of standardized Boswellia serrata extract (AflapinⓇ) in osteoarthritis: A systematic review and sub-group meta-analysis study

BACKGROUND AND PURPOSE

Osteoarthritis (OA) is a joint disease characterized by pain, inflammation, and physical disability. Boswellia serrata (BS) is widely studied for its effectiveness in OA condition. Our systematic review and meta-analysis study was aimed to evaluate BS extract efficacy in OA. A sub-group analysis was performed to compare the efficacy of a standardized BS extract (AflapinⓇ) with other BS extracts.

METHODS

Randomized controlled trials, identified from three online databases, evaluating the effect of BS extracts in OA were included. Quality of studies was assessed using PEDro scale and risk of bias was assessed using Cochrane Risk of Bias tool. Pooled effect was reported as mean difference (MD) and 95% confidence interval. Study was conducted as per the Cochrane guidelines (PROSPERO registration ID: CRD42023411356).

RESULTS

Nine RCTs with 712 participants were included. All studies (except one) were good quality studies. BS supplementation significantly reduced VAS (MD: -10.71; p<0.00001), LFI (MD: -2.99; p<0.00001), WOMAC-pain (MD: -10.69; p<0.0001), WOMAC-stiffness (MD: -5.49; p<0.00001), and WOMAC-function (MD: -10.69; p<0.00001) scores compared to control therapy. By sub-group analysis, AflapinⓇ supplementation showed greater reduction in VAS (MD: -16.09 vs -4.68), LFI (MD: -3.81 vs -2.01), WOMAC-pain (MD: -18.68 vs -7.07), WOMAC-stiffness (MD: -14.25 vs -3.78), and WOMAC-function (MD: -14.99 vs -8.41) scores as compared to other BS therapies.

CONCLUSIONS

BS supplementation is effective OA symptomatic management. Sub-group analysis revealed that AflapinⓇ supplementation may be better in improving the symptoms of OA which needs to be confirmed by more comparative clinical studies.

Triterpenes Drug Delivery Systems, a Modern Approach for Arthritis Targeted Therapy

Arthritis is a major cause of disability. Currently available anti-arthritic drugs, such as disease-modifying anti-rheumatic drugs (DMARDs), have serious side-effects associated with long-term use. Triterpenoids are natural products with known anti-inflammatory properties, and many have revealed efficiency against arthritis both in vitro and in vivo in several animal models, with negligible cytotoxicity. However, poor bioavailability due to low water solubility and extensive metabolism upon oral administration hinder the therapeutic use of anti-arthritic triterpenoids. Therefore, drug delivery systems (DDSs) able to improve the pharmacokinetic profile of triterpenoids and achieve sustained drug release are useful alternatives for targeted delivery in arthritis treatment. Several DDSs have been described in the literature for triterpenoid delivery, including microparticulate and nanoparticulate DDSs, such as polymeric micro and nanoparticles (NPs), polymeric micelles, liposomes, micro and nanoemulsions, and hydrogels. These systems have shown superior therapeutic effects in arthritis compared to the free drugs and are similar to currently available anti-arthritic drugs without significant side-effects. This review focuses on nanocarriers for triterpenoid delivery in arthritis therapy, including osteoarthritis (OA), rheumatoid arthritis (RA) and gout that appeared in the literature in the last ten years.

In situ Formation of Polymer Microparticles in Bacterial Nanocellulose Using Alternative and Sustainable Solvents to Incorporate Lipophilic Drugs

Bacterial nanocellulose has been widely investigated in drug delivery, but the incorporation of lipophilic drugs and controlling release kinetics still remain a challenge. The inclusion of polymer particles to encapsulate drugs could address both problems but is reported sparely. In the present study, a formulation approach based on in situ precipitation of poly(lactic-co-glycolic acid) within bacterial nanocellulose was developed using and comparing the conventional solvent N-methyl-2-pyrrolidone and the alternative solvents poly(ethylene glycol), Cyrene^TM and ethyl lactate. Using the best-performing solvents N-methyl-2-pyrrolidone and ethyl lactate, their fast diffusion during phase inversion led to the formation of homogenously distributed polymer microparticles with average diameters between 2.0 and 6.6 µm within the cellulose matrix. Despite polymer inclusion, the water absorption value of the material still remained at ~50% of the original value and the material was able to release 32 g/100 cm² of the bound water. Mechanical characteristics were not impaired compared to the native material. The process was suitable for encapsulating the highly lipophilic drugs cannabidiol and 3-O-acetyl-11-keto-β-boswellic acid and enabled their sustained release with zero order kinetics over up to 10 days. Conclusively, controlled drug release for highly lipophilic compounds within bacterial nanocellulose could be achieved using sustainable solvents for preparation.

Co-encapsulation of Curcumin and Boswellic Acids in Chitosan-Coated Niosome: An In-vitro Digestion Study

AIM

In this study chitosan-coated niosome (ChN) was utilized for bioavailability enhancement of curcumin (Cn) and boswellic acids (BAs).

METHODS

The bare niosome (BN) was prepared by the heating method and optimized by using the mixture design procedure. Physicochemical stability, as well as the in vitro release, and bioavailability of Cn and BAs in BN and ChN were studied.

RESULTS

The optimized BN had a mean diameter of 70.00 ± 0.21 nm and surface charge of -31.00 ± 0.25 mv, which changed to 60.01 ± 0.20 nm and +40.00 ± 0, respectively, in ChN. In-vitro digestion study revealed chitosan layer augmented the bioavailability of Cn and BAs to 79.02 ± 0.13 and 81 ± 0.10, respectively. The chitosan layer obviously improved the physical stability of Cn and BA in the niosome vehicle, by means of vesicle size, zeta potential, and encapsulation efficiency.

CONCLUSION

The Chitosan-coated niosome was considered to be promising delivery system for increasing the bioavailability of Cn and BAs.

Herbal nanomedicines: Recent advancements, challenges, opportunities and regulatory overview

BACKGROUND

Herbal Nano Medicines (HNMs) are nano-sized medicine containing herbal drugs as extracts, enriched fractions or biomarker constituents. HNMs have certain advantages because of their increased bioavailability and reduced toxicities. There are very few literature reports that address the common challenges of herbal nanoformulations, such as selecting the type/class of nanoformulation for an extract or a phytochemical, selection and optimisation of preparation method and physicochemical parameters. Although researchers have shown more interest in this field in the last decade, there is still an urgent need for systematic analysis of HNMs.

PURPOSE

This review aims to provide the recent advancement in various herbal nanomedicines like polymeric herbal nanoparticles, solid lipid nanoparticles, phytosomes, nano-micelles, self-nano emulsifying drug delivery system, nanofibers, liposomes, dendrimers, ethosomes, nanoemulsion, nanosuspension, and carbon nanotube; their evaluation parameters, challenges, and opportunities. Additionally, regulatory aspects and future perspectives of herbal nanomedicines are also being covered to some extent.

METHODS

The scientific data provided in this review article are retrieved by a thorough analysis of numerous research and review articles, textbooks, and patents searched using the electronic search tools like Sci-Finder, ScienceDirect, PubMed, Elsevier, Google Scholar, ACS, Medline Plus and Web of Science.

RESULTS

In this review, the authors suggested the suitability of nanoformulation for a particular type of extracts or enriched fraction of phytoconstituents based on their solubility and permeability profile (similar to the BCS class of drugs). This review focuses on different strategies for optimising preparation methods for various HNMs to ensure reproducibility in context with all the physicochemical parameters like particle size, surface area, zeta potential, polydispersity index, entrapment efficiency, drug loading, and drug release, along with the consistent therapeutic index.

CONCLUSION

A combination of herbal medicine with nanotechnology can be an essential tool for the advancement of herbal medicine research with enhanced bioavailability and fewer toxicities. Despite the challenges related to traditional medicine's safe and effective use, there is huge scope for nanotechnology-based herbal medicines. Overall, it is well stabilized that herbal nanomedicines are safer, have higher bioavailability, and have enhanced therapeutic value than conventional herbal and synthetic drugs.

Considerations to Be Taken When Carrying Out Medicinal Plant Research-What We Learn from an Insight into the IC50 Values, Bioavailability and Clinical Efficacy of Exemplary Anti-Inflammatory Herbal Components

Medicinal plants represent a big reservoir for discovering new drugs against all kinds of diseases including inflammation. In spite the large number of promising anti-inflammatory plant extracts and isolated components, research on medicinal plants proves to be very difficult. Based on that background this review aims to provide a summarized insight into the hitherto known pharmacologically active concentrations, bioavailability, and clinical efficacy of boswellic acids, curcumin, quercetin and resveratrol. These examples have in common that the achieved plasma concentrations were found to be often far below the determined IC50 values in vitro. On the other hand demonstrated therapeutic effects suggest a necessity of rethinking our pharmacokinetic understanding. In this light this review discusses the value of plasma levels as pharmacokinetic surrogates in comparison to the more informative value of tissue concentrations. Furthermore the need for new methodological approaches is addressed like the application of combinatorial approaches for identifying and pharmacokinetic investigations of active multi-components. Also the physiological relevance of exemplary in vitro assays and absorption studies in cell-line based models is discussed. All these topics should be ideally considered to avoid inaccurate predictions for the efficacy of herbal components in vivo and to unlock the "black box" of herbal mixtures.

Plant-Derived Natural Products in Cancer Research: Extraction, Mechanism of Action, and Drug Formulation

Cancer is one of the main causes of death globally and considered as a major challenge for the public health system. The high toxicity and the lack of selectivity of conventional anticancer therapies make the search for alternative treatments a priority. In this review, we describe the main plant-derived natural products used as anticancer agents. Natural sources, extraction methods, anticancer mechanisms, clinical studies, and pharmaceutical formulation are discussed in this review. Studies covered by this review should provide a solid foundation for researchers and physicians to enhance basic and clinical research on developing alternative anticancer therapies.

Antiproliferative effects of boswellic acid-loaded chitosan nanoparticles on human lung cancer cell line A549

Aim: In the present study boswellic acids-loaded chitosan nanoparticles were synthesized using ionic gelation technique. The influence of independent variables were studied and optimized on dependent variables using central composite design. Methodology & results: The designed nanoparticles were observed spherical in shape with an average size of 67.5-187.2 nm and have also shown an excellent entrapment efficiency (80.06 ± 0.48). The cytotoxicity assay revealed enhanced cytotoxicity for drug-loaded nanoparticles in contrast to the free drug having an IC₅₀ value of 17.29 and 29.59 μM, respectively. Flow cytometry confirmed that treatment of cells with 40 μg/ml had arrested 22.75 ± 0.3% at SubG₀ phase of the cell cycle when compared with untreated A459 cells. The observed results justified the boswellic acids-loaded chitosan nanoparticles were effective due to greater cellular uptake, sustained intercellular drug retention and enhanced antiproliferative effect by inducing apoptosis.

Formulation of Nanospanlastics as a Promising Approach for ‎Improving the Topical Delivery of a Natural Leukotriene Inhibitor (3-‎Acetyl-11-Keto-β-Boswellic Acid): Statistical Optimization, in vitro ‎Characterization, and ex vivo Permeation Study

Purpose

The current study aimed to discuss the potential of nanospanlastics as a surfactant-based vesicular system for improving the topical delivery of 3-acetyl-11-keto-β-boswellic acid (AKBA). AKBA is a potent anti-inflammatory drug, but it has poor oral bioavailability due to its poor aqueous solubility. Moreover, the topical delivery of AKBA is difficult due to its high lipophilicity. To overcome these drawbacks, AKBA was formulated as deformable elastic nanovesicles and nanospanlastics, for improving its topical delivery.

Materials and Methods

AKBA-loaded spanlastic nanovesicles (SNVs) were formulated by ethanol injection technique according to 2³ factorial design using Span 60 as a non-ionic surfactant and Tween 80 as edge activator (EA) to investigate the effect of different independent variables on entrapment efficiency (EE%), % drug released after 8 hr (Q_8h) and particle size (PS) using Design-Expert software. In vitro characterization, stability test and ex vivo permeation study of the optimized formula were performed.

Results

The choice of the optimized formula was based on the desirability criteria.‎ F7 was selected as the optimized formula because it has the highest desirability value of 0.648. F7 exhibited EE% of 90.04±0.58%, Q_8h of 96.87±2.67%, PS of 255.8±2.67 nm, and zeta potential of −49.56 mV. F7 appeared as spherical well-defined vesicles in both scanning electron microscope (SEM) and transmission electron microscope (TEM). The Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) studies investigated the absence of interaction between AKBA and ‎different excipients and good encapsulation of AKBA within SNVs. F7 retained both physical and chemical stability after storage for 3 months at 4–8 °C. Ex vivo permeation test exhibited significant enhancement of permeability of F7 across rat skin than the free drug.

Conclusion

Nanospanlastics could be a promising approach for improving the permeability and topical delivery of AKBA.

Acetyl-11-keto-β-boswellic acid extracted from Boswellia serrata promotes Schwann cell proliferation and sciatic nerve function recovery

Frankincense can promote blood circulation. Acetyl-11-keto-β-boswellic acid (AKBA) is a small molecule with anti-inflammatory properties that is derived from Boswellia serrata. Here, we hypothesized that it may promote regeneration of injured sciatic nerve. To address this hypothesis, we established a rat model of sciatic nerve injury using a nerve clamping method. Rats were administered AKBA once every 2 days at doses of 1.5, 3, and 6 mg/kg by intraperitoneal injection for 30 days from the 1^st day after injury. Sciatic nerve function was evaluated using the sciatic functional index. Degree of muscle atrophy was measured using the triceps surae muscle Cuadros index. Neuropathological changes were observed by hematoxylin-eosin staining. Western blot analysis was used to detect expression of phospho-extracellular signal-regulated kinase 1 and 2 (p-ERK1/2) in injured nerve. S100 immunoreactivity in injured nerve was detected by immunohistochemistry. In vivo experiments showed that 3 and 6 mg/kg AKBA significantly increased sciatic nerve index, Cuadros index of triceps muscle, p-ERK1/2 expression, and S100 immunoreactivity in injured sciatic nerve of sciatic nerve injury model rats. Furthermore, for in vitro experiments, Schwann cells were treated with AKBA at 0-20 μg/mL. Proliferation of Schwann cells was detected by Cell Counting Kit-8 colorimetry assay. The results showed that 2 μg/mL AKBA is the optimal therapeutic concentration. In addition, ERK phosphorylation levels increased following 2 μg/mL AKBA treatment. In the presence of the ERK1/2 inhibitor, PD98059 (2.5 μL/mL), the AKBA-induced increase in p-ERK1/2 protein expression was partially abrogated. In conclusion, our study shows that AKBA promotes peripheral nerve regeneration with ERK protein phosphorylation playing a key role in this process.

Pentacyclic Triterpene Bioavailability: An Overview of In Vitro and In Vivo Studies

Pentacyclic triterpenes are naturally found in a great variety of fruits, vegetables and medicinal plants and are therefore part of the human diet. The beneficial health effects of edible and medicinal plants have partly been associated with their triterpene content, but the in vivo efficacy in humans depends on many factors, including absorption and metabolism. This review presents an overview of in vitro and in vivo studies that were carried out to determine the bioavailability of pentacyclic triterpenes and highlights the efforts that have been performed to improve the dissolution properties and absorption of these compounds. As plant matrices play a critical role in triterpene bioaccessibility, this review covers literature data on the bioavailability of pentacyclic triterpenes ingested either from foods and medicinal plants or in their free form.

Nanoparticle formulation of 11-keto-β-boswellic acid (KBA): anti-inflammatory activity and in vivo pharmacokinetics

CONTEXT

The oleo-gum-resin of Boswellia serrata Roxb. (Burseraceae) is widely used for the treatment of inflammatory diseases such as osteoarthritis, rheumatoid arthritis and cancer. Anti-inflammatory activity of 11-keto-β-boswellic acid (KBA) is impeded by poor oral bioavailability due to its high lipid solubility, rapid phase-1 metabolism and poor intestinal permeability.

OBJECTIVE

This study developed a poly-dl-lactide-co-glycolide-based nanoparticle formulation of KBA to improve its oral bioavailability and in vivo anti-inflammatory activity.

MATERIALS AND METHODS

KBA was isolated from the oleo-gum resin of B. serrata, and its nanoparticle formulation (KBA-NPs) was prepared by the emulsion-diffusion-evaporation method. Oral bioavailability of KBA and KBA-NPs was studied at 50 mg/kg p.o. dose in Sprague-Dawley rats, and further evaluated for in vivo anti-inflammatory activity in carrageenan-induced rat paw oedema assay at the same dose level.

RESULTS

The prepared KBA-NPs had a particle size of 152.6 nm with polydispersity index of 0.194, 79.7% entrapment efficiency and a cumulative 61.5% release of KBA from KBA-NPs, at 72 h. KBA-NPs showed 60.8% inhibition of rat paw oedema at 5 h as compared to 34.9% as that of KBA. The results of oral bioavailability study and in vivo anti-inflammatory activity showed 7- and 1.7-fold increase in bioavailability and anti-inflammatory activity, respectively, of KBA in KBA-NPs as compared to KBA alone.

CONCLUSION

The results of improved oral bioavailability and in vivo anti-inflammatory activity of KBA-NPs suggested successful development of KBA nanoparticle formulation.

Blebbistatin-Loaded Poly(d,l-lactide-co-glycolide) Particles For Treating Arthrofibrosis

Joint immobility is a debilitating complication of articular trauma that is characterized by thickening and stiffening of the joint capsule and the formation of fibrotic lesions inside joints. Capsule release surgery can temporarily restore mobility, but contraction often recurs due to the contractile activities of fibroblasts, which exert tension on the capsule ECM via nonmuscle myosin II. Based on these findings we hypothesized that blebbistatin, a drug that reversibly inhibits the activity of this protein, would relax ECM tension imposed by fibroblasts and reduce fibrosis. In this study, we characterized the effectiveness of blebbistatin as an anticontractile treatment. Given that sustained suppression of contractile activity may be required to achieve capsule release and reduce fibrosis, we compared the effects on fibroblast-mediated collagen ECM displacement of blebbistatin-loaded poly(lactide-co-gylcolide) (PLGA) particles versus bolus blebbistatin dosing. Time-lapse imaging of fluorescent microspheres embedded in collagen gels confirmed that PLGA/blebbistatin inhibited force generation and reduced both gel displacement and rate of displacement. In addition, collagen production at 10 days was significantly reduced. Taken together, these data indicate that blebbistatin-loaded PLGA particles can be used to inhibit fibroblast force-generation and reduce collagen production and lay the foundation for optimization of drug delivery technology for treating arthrofibrosis.