Oral bioavailability enhancement and hepatoprotective effects of thymoquinone by self-nanoemulsifying drug delivery system

Flufenamic Acid-Loaded Self-Nanoemulsifying Drug Delivery System for Oral Delivery: From Formulation Statistical Optimization to Preclinical Anti-Inflammatory Assessment

This research work aimed to prepare and optimize "self-nanoemulsifying drug delivery system (SNEDDS)" by applying full factorial design (FFD) to improve solubilization and subsequently antiinflammatory efficacy of flufenamic acid (FLF). Suitable excipients were screened out based on the maximum solubility of FLF. FFD was applied using lipid (X1) and surfactant (X2) as independent variables against droplet size (Y1, nm), zeta potential (Y2, mV) and polydispersity index (PDI, Y3). Desirability function identified the main factors influencing the responses and possible interactions. Moreover, the optimized formulation (OFS1) was characterized and compared with pure FLF suspension. The prepared formulations (FS1-FS9) showed the size, PDI and zeta potential of 14.2-110.7 nm, 0.29-0.62 and -15.1 to -28.6 mV, respectively. The dispersion and emulsification of all formulations meted out within 2 min suggesting immediate release and successful solubilization. The optimized formulation OFS1 demonstrated ~ 85% drug release within 1 h which was significantly higher (p ˂ 0.05) than FLF suspension. The hemolysis study negated the probable interaction with blood cells. Eventually, improved anti-inflammatory efficacy was envisaged which might be attributed to increased drug solubility and absorption. The present nanocarrier could be a promising approach and alternative to conventional dosage form.

Thymoquinone-Loaded Soy-Phospholipid-Based Phytosomes Exhibit Anticancer Potential against Human Lung Cancer Cells

Thymoquinone (TQ), a natural polyphenol, has been associated with various pharmacological responses; however, low bioavailability of TQ limits its clinical application. Thus, a novel phytosomal delivery system of TQ-Phospholipon® 90H complex (TQ-phytosome) was developed by refluxing combined with anti-solvent precipitation. This TQ delivery system was optimized by a three-factor, three-level Box-Behnken design. The optimized TQ-phytosome size was (45.59 ± 1.82 nm) and the vesicle size was confirmed by transmission electron microscopy. The in vitro release pattern of the formulation indicated a biphasic release pattern, where an initial burst release was observed within 2 h, followed by a prolonged release. A remarkable increase in dose-dependent cytotoxicity was evident from the significant decrease in IC50 value of TQ-phytosomes (4.31 ± 2.21 µM) against the A549 cell line. The differential effect of TQ-phytosomes in cell cycle analysis was observed, where cancer cells were accumulated on G2-M and pre-G1 phases. Furthermore, increased apoptotic induction and cell necrosis of TQ-phytosomes were revealed with the annexin V staining technique via activation of caspase-3. In reactive oxygen species (ROS) analysis, TQ-phytosomes acted to significantly increase ROS generation in A549 cells. In conclusion, the sustained release profile with significantly-improved anticancer potential could be obtained with TQ by this phytosomal nanocarrier platform.

Thermoresponsive sol-gel improves ocular bioavailability of Dipivefrin hydrochloride and potentially reduces the elevated intraocular pressure in vivo

The present study involves the development of Dipivefrin hydrochloride (DV) containing Poloxamers (P407 and P188)-Carbopol-934 (CP) based thermoresponsive-gels for the management of elevated intraocular pressure (IOP). Optimal formulation was evaluated for gelation temperature (T_gel), physicochemical and viscoelastic properties, in-vitro gel dissolution and drug release studies. The in-vivo safety, precorneal retention, ocular pharmacokinetics and efficacy in reducing IOP were also evaluated. T_gel of DV-containing thermoresponsive-gels were between 35.1 and 38.9 °C and it was Poloxamers and CP concentrations dependent. The optimal formulation (F8), composed of 20% P407, 5% P188 and 0.15% CP (w/v), had a T_gel of 35 °C. Its viscosity indicated good flow at room temperature and ability to convert to gel at ocular temperature and the rheology studies revealed favorable characteristics for its ocular use. In precorneal retention experiment, F8 indicated significantly higher area under concentrations curves as compared to DV-aqueous suspension (DV-AqS). In-vivo ocular pharmacokinetics indicated a significant improvement in ophthalmic bioavailability of epinephrine (active form of DV). F8 was non-irritant to the eyes and showed a successful, continuous and superior ability to reduce IOP compared to DV-AqS in rabbits. In conclusion, our developed system could be an appropriate substitute to the conventional DV eye preparations in the management of elevated IOP.

Alaofi A, Awan ZA, Alqarni HM, Alhakamy NA. Optimization of Thymoquinone-Loaded Coconut Oil Nanostructured Lipid Carriers for the Management of Ethanol-Induced Ulcer

In the global incidence of peptic ulcer, with the associated rates of hospitalizations and mortality are increasing, in the United States, peptic ulcer disease affects approximately 4.6 million people annually, with an estimated 10% of the US population having evidence of a duodenal ulcer. The present research aims to find a novel treatment for ethanol induced ulcer by loading thymoquinone (TQ) on a nanostructured lipid carrier (NLC), using Compritol® 888 and coconut oil. The TQ-loaded coconut oil NLC was formulated using melt emulsification combined with a sonication method using Poloxamer 188 as a surfactant. Finally, the optimization of the formulations was performed on a three-factor, three-level Box-Behnken statistical design, with 85.63% entrapment efficiency of TQ in the optimized formulation. A biphasic release pattern of the formulation was recorded in an in vitro drug release study, where the initial burst release of the drug was observed in the first 2 h, followed by a gradual release. Later, the TQ-loaded coconut oil NLC was found to protect the gastric mucous membrane more effectively (78.95% in.; p < 0.01) in an alcohol-induced ulcer model, whereas the TQ suspension showed 30.87% inhibition (p < 0.05) of the ulcerative index, when compared with the ulcer control group. The histopathological evaluations of the stomach in ulcer-induced animals demonstrated protection potential of TQ-loaded coconut oil NLC against an alcohol-induced gastric ulcer. In a nutshell, the entrapment of TQ within the NLC was found to deliver the entrapped drug more effectively when administered through an oral route to possess a gastroprotective effect.

Thymoquinone-encapsulated chitosan nanoparticles coated with polysorbate 80 as a novel treatment agent in a reserpine-induced depression animal model

Depression is a mental illness with a high prevalence in humans reaching 21% of the worldwide population.The present study aims to evaluate the antidepressant effect of different formulations of Thymoquinone; free Thymoquinone (TQ), Thymoquinone-loaded Chitosan nanoparticles (TQ-TPP-Cs NPs) and Thymoquinone-loaded Chitosan nanoparticles coated with polysorbate 80 (TQ-TPP-Cs NPs-PSb80) that have been prepared to avoid the low bioavailability of TQ. Rats were randomly separated into control rats, depression control induced by reserpine, rat model treated with TQ, rat model treated with TQ-TPP-Cs NPs and rat model treated with TQ-TPP-Cs NPs-PSb80. The results indicate that TQ-TPP-Cs NPs loaded with polysorbate 80 was more efficient in ameliorating the behavioral and neurochemical changes induced by reserpine than TQ and TQ-TPP-Cs NPs. Formulationswere characterized for size, morphology, encapsulation efficiency and in vitro drug release before their use in treatment. Reserpine induced a reduction in motor activity and swimming time and increased immobility time as indicated from the open field test (OFT) and forced swimming test (FST). In addition, a significant decrease in the monoamine neurotransmitters serotonin (5-HT), norepinephrine (NE) and dopamine (DA) was recorded in the cortex, hippocampus and striatum of reserpine-treated rats. The present data suggest that the antidepressant efficacy of TQ could be enhanced by engaging TQ with chitosan nanoparticles as a drug carrier and the formulations were modified by coating with polysorbate 80.

Nanocarriers: more than tour de force for thymoquinone

Introduction: Thymoquinone (TQ), 2-isopropyl-5-methylbenzo-1, 4-quinone, the main active constituent of Nigella sativa (NS) plant, has been proven to be of great therapeutic aid in various in vitro and in vivo conditions. Despite the promising therapeutic activities of TQ, this molecule is not yet in the clinical trials, restricted by its poor biopharmaceutical properties including photo-instability.Area covered: This review compiles the different types of polymeric and lipidic nanocarriers (NCs), encapsulating TQ for their improved oral bioavailability, and augmented in vitro and in vivo efficacy, evidenced on various pathologies. Furthermore, we provide a comprehensive overview of TQ in relation to its encapsulation approaches advancing the delivery and improving the efficacy of TQ.Expert opinion: TQ was first identified in the essential oil of Nigella sativa L. black seed. TQ has not been used in formulations because it is a highly hydrophobic drug having poor aqueous solubility. To deal with the poor physicochemical problems associated with TQ, various NCs encapsulating TQ have been tried in the past. Nevertheless, these NCs could be impending in bringing forth this potential molecule to clinical reality. This will also be beneficial for a large research community including pharmaceutical & biological sciences and translational researchers.

Enhanced oral bioavailability and hepatoprotective activity of thymoquinone in the form of phospholipidic nano-constructs

Background: The poor biopharmaceutical properties of thymoquinone (TQ) obstruct its development as a hepatoprotective agent. To surmount the delivery challenges of TQ, phospholipid nanoconstructs (PNCs) were constructed.Method: PNCs were constructed employing microemulsification technique and systematic optimization by three-factor three level Box-Behnken design.Result: Optimized PNC composition exhibited nano size (<100 nm), spherical morphology, within acceptable range of polydispersity index (0.55), high drug entrapment efficiency (>90%), controlled drug release pattern, and neutral surface charge (zeta potential of -0.65 mV). After oral administration of a single dose of PNC, it showed a relative bioavailability of 386.03% vis-à-vis plain TQ suspension. Further, TQ-loaded PNC demonstrated significant enhanced hepato-protective effect vis-à-vis pure TQ suspension and silymarin, as evidenced by reduction in the ALP, ALT, AST, bilirubin, and albumin level and ratified by histopathological analysis.Conclusion: TQ-loaded PNCs can be efficient nano-platforms for the management of hepatic disorders and promising drug delivery systems to enhance oral bioavailability of this hydrophobic molecule.

Novel thymoquinone loaded chitosan-lecithin micelles for effective wound healing: Development, characterization, and preclinical evaluation

While the wound healing activity of thymoquinone (TQ) is well known, its clinical effectiveness remains limited due to the inherently low aqueous solubility, resulting in suboptimal TQ exposure in the wound sites. To address these problems, TQ loaded chitosan-lecithin micelles for wound healing were prepared and its efficacy was determined in vivo in the excision wound model. Firstly, the co-block polymer of chitosan and soya lecithin was synthesized which has low critical micelle concentration (CMC). Its employment in the development of TQ loaded polymeric micelles by Self-assembly method resulted in the stable polymeric micelle composition having requisite small particle size (<100 nm), narrow size distribution (close to zero) and high entrapment efficiency (98.77 %) of TQ. The designed nano-carriers not only substantially entrapped the drug but also controlled the release rate of TQ. The TQ-polymeric micelle hydrogel exhibited superior wound healing efficacy to the native TQ and Silver Sulphadiazine.

Thymoquinone (2-Isoprpyl-5-methyl-1, 4-benzoquinone) as a chemopreventive/anticancer agent: Chemistry and biological effects

Cancer remains the topmost disorders of the mankind and number of cases is unceasingly growing at unprecedented rates. Although the synthetic anti-cancer compounds still hold the largest market in the modern treatment of cancer, natural agents have always been tried and tested for potential anti-cancer properties. Thymoquinone (TQ), a monoterpene and main ingredient in the essential oil of Nigella sativa L. has got very eminent rankings in the traditional systems of medicine for its anti-cancer pharmacological properties. In this review we summarized the diverse aspects of TQ including its chemistry, biosynthesis, sources and pharmacological properties with a major concern being attributed to its anti-cancer efficacies. The role of TQ in different aspects involved in the pathogenesis of cancer like inflammation, angiogenesis, apoptosis, cell cycle regulation, proliferation, invasion and migration have been described. The mechanism of action of TQ in different cancer types has been briefly accounted. Other safety and toxicological aspects and some combination therapies involving TQ have also been touched. A detailed literature search was carried out using various online search engines like google scholar and pubmed regarding the available research and review accounts on thymoquinone upto may 2019. All the articles reporting significant addition to the activities of thymoquinone were selected. Additional information was acquired from ethno botanical literature focusing on thymoquinone. The compound has been the centre of attention for a long time period and researched regularly in quite considerable numbers for its various physicochemical, medicinal, biological and pharmacological perspectives. Thymoquinone is studied for various chemical and pharmacological activities and demonstrated promising anti-cancer potential. The reviewed reports confirmed the strong anti-cancer efficacy of thymoquinone. Further in-vitro and in-vivo research is strongly warranted regarding the complete exploration of thymoquinone in ethnopharmacological context.

Solidified SNEDDS for the oral delivery of rifampicin: Evaluation, proof of concept, in vivo kinetics, and in silico GastroPlusTM simulation

The present investigation was performed to develop a rifampicin (RIF)-loaded solidified self-nanoemulsifying drug delivery system (SNEDDS) (solidified RIF-OF1) for in vitro and in vivo evaluations. Optimized formulations were tested for their powder flow characteristics, loading efficiency, and in vitro dissolution (at pH-1.2, 6.8 and 7.4). Compatibility studies were also performed. The formulations were also tested for hemocompatibility, intestinal permeation, histopathological effects, and in vivo pharmacokinetics. Additionally, an in silico simulation study using GastroPlus was performed. At different varied pH values, we observed immediate release (T85% within 15 min) based on the dissolution profile. This could be due to labrasol-assisted RIF solubilization. In vitro hemolysis study of the reconstituted RIF-OF1 revealed normal architecture of erythrocytes compared to the positive control (lysed and fragmented). Through in vivo permeation and biopsy studies, a rationale for facilitated intestinal permeation of RIF with components deemed physiological safe (normal anatomy of mucosal membrane evidenced from biopsy study) could be established. The in vitro-in vivo correlation (IVIVC) plus module of GastroPlusTM simulation showed a good IVIVC between in vitro release and in vivo absorption with a predicted systemic absorption of ∼96.5%. Solidified SNEDDS showed improved pharmacokinetic profiles compared to RIF suspension. Solid RIF-SNEDDS was demonstrated to be a suitable carrier for enhanced intestinal permeation and oral bioavailability. Hence, it may serve as a suitable alternative to conventional delivery systems for tuberculosis treatment.

Development and evaluation of doxorubicin self nanoemulsifying drug delivery system with Nigella Sativa oil against human hepatocellular carcinoma

OBJECTIVE

The development of self nano emulsifying co-delivery system of doxorubicin and Nigella sativa oil for potentiating the anticancer effects against HepG2 cell lines.

MATERIALS AND METHODS

SNEDDS were formulated by using Labrafil and N. sativa oil (3:2% w/w), Kolliphor RH40 (15% w/w), glycerol (5% w/w) as oil phase, surfactant and co-surfactant while deionized water (75% v/v) used as an aqueous phase. Optimized SNEDDS was evaluated for drug release and in vitro anticancer efficacy in liver cancer (HepG2) cell line.

RESULTS AND DISCUSSION

The selected formulation (F6) has a mean particle size of 79.7 nm with PDI 0.098 and the minimum viscosity of 16.42 cps with % transmittance of 1.332 with maximum drug release of 96.968% in 32 h as compared to DOX alone. Stability data showed stable emulsion in both 25⁰C and -4⁰C. F6 showed improved efficacy in HepG2 cells by cytotoxicity, showed significant results p<.05 with 2.5 μg/ml of (inhibitory concentration) IC50.

CONCLUSION

The overall study displayed that co-delivery of DOX and Nigella sativa oil in the form of SNEDDS may be an efficient carrier for further in vivo studies using oral delivery in human hepatocellular carcinoma in mammals.

Protective Roles of Thymoquinone Nanoformulations: Potential Nanonutraceuticals in Human Diseases

The focus on nanotechnology for improved bioavailability and drug delivery is of increasing importance for control of different human diseases. Therefore, numerous nanoformulations have been developed for the oral bioavailability of different drugs. This review introduces applications of nanomedicine to enhance the biological activities of thymoquinone (TQ) to control different diseases in several in vivo studies as a preliminary investigation for human disease treatment with nano-TQ. Nano-TQ effectively augments the anticancer roles of doxorubicin by upregulation of P53 and downregulation of Bcl2 and potentiates paclitaxel's apoptosis in MCF-7 breast cancer cells. Moreover, nano-TQ protects against diabetes, inflammation, CNS, and hepatotoxicity, mainly by enhancement of organs' antioxidant status. We summarize the pros and cons of several FDA approved nanoparticle-based therapeutics and discuss the roadblocks in clinical translation, along with potential nano-TQ strategies to overcome these roadblocks. From this review, we can conclude that nano-TQ may be considered as a promising nutraceutical for human health.

Spice-Derived Bioactive Ingredients: Potential Agents or Food Adjuvant in the Management of Diabetes Mellitus

Spices possess tremendous therapeutic potential including hypoglycemic action, attributed to their bioactive ingredients. However, there is no study that critically reviewed the hypoglycemic potency, safety and the bioavailability of the spice-derived bioactive ingredients (SDBI). Therefore, the aim of the study was to comprehensively review all published studies regarding the hypoglycemic action of SDBI with the purpose to assess whether the ingredients are potential hypoglycemic agents or adjuvant. Factors considered were concentration/dosages used, the extent of blood glucose reduction, the IC50 values, and the safety concern of the SDBI. From the results, cinnamaldehyde, curcumin, diosgenin, thymoquinone (TQ), and trigonelline were showed the most promising effects and hold future potential as hypoglycemic agents. Conclusively, future studies should focus on improving the tissue and cellular bioavailability of the promising SDBI to achieve greater potency. Additionally, clinical trials and toxicity studies are with these SDBI are warranted.

Neuropharmacological Potential and Delivery Prospects of Thymoquinone for Neurological Disorders

Thymoquinone (TQ) is an active ingredient isolated from Nigella sativa and has various pharmacological activities, such as protection against oxidative stress, inflammation, and infections. In addition, it might be a potential neuropharmacological agent because it exhibits versatile potential for attenuating neurological impairments. It features greater beneficial effects in toxin-induced neuroinflammation and neurotoxicity. In various models of neurological disorders, it demonstrates emergent functions, including safeguarding various neurodegenerative diseases and other neurological diseases, such as stroke, schizophrenia, and epilepsy. TQ also has potential effects in trauma mediating and chemical-, radiation-, and drug-induced central nervous system injuries. Considering the pharmacokinetic limitations, research has concentrated on different TQ novel formulations and delivery systems. Here, we visualize the neuropharmacological potential, challenges, and delivery prospects of TQ, specifically focusing on neurological disorders along with its chemistry, pharmacokinetics, and toxicity.

Measuring the emulsification dynamics and stability of self-emulsifying drug delivery systems

Self-emulsifying drug delivery systems (SEDDS) are one of the most promising technologies in the drug delivery field, particularly for addressing solubility and bioavailability issues of drugs. The development of these drug carriers excessively relies in visual observations and indirect determinations. The present manuscript intended to describe a method able to measure the emulsification of SEDDS, both micro and nano-emulsions, able to measure the droplet size and to evaluate the physical stability of these formulations. Additionally, a new process to evaluate the physical stability of SEDDS after emulsification was also proposed, based on a cycle of mechanical stress followed by a resting period. The use of a multiparameter continuous evaluation during the emulsification process and stability was of upmost value to understand SEDDS emulsification process. Based on this method, SEDDS were classified as fast and slow emulsifiers. Moreover, emulsification process and stabilization of emulsion was subject of several considerations regarding the composition of SEDDS as major factor that affects stability to physical stress and the use of multicomponent with different properties to develop a stable and robust SEDDS formulation. Drug loading level is herein suggested to impact droplets size of SEDDS after dispersion and SEDDS stability to stress conditions. The proposed protocol allows an online measurement of SEDDS droplet size during emulsification and a rationale selection of excipients based on its emulsification and stabilization performance.