High efficacy, rapid onset nanobiolosomes of sildenafil as a topical therapy for erectile dysfunction in aged rats

Dermal drug delivery via bilosomes: a synergistic integration for better therapeutic outcomes

The dermal route is commonly used to deliver the drugs at the targeted site and achieve maximum therapeutic efficacy. The stratum corneum, the uppermost layer of the skin, presents a significant diffusional barrier for most drugs. Various nanoformulations face challenges such as limited drug absorption and inadequate retention at the targeted site, frequently hindering therapeutic efficacy. Researchers are increasingly exploring innovative strategies that leverage nanotechnology and specialized carriers to address these challenges and enhance the outcomes of dermal medications. A novel drug delivery system, bilosomes, has been designed as a potential vesicular carrier system for the dermal route. Bilosomes are colloidal, lipid-based vesicles stabilized with bile salts, offering greater stability during storage and transportation. The lipid bilayer of bilosomes imparts ultra-flexibility, facilitating penetration through the stratum corneum. This review explores the use of bilosomes in dermal formulations for treating diverse diseases, their developmental techniques, and characterization, and it sheds light on their advantages over traditional lipid nanocarriers.

Nanotechnology-based drug delivery platforms for erectile dysfunction: addressing efficacy, safety, and bioavailability concerns

Erectile dysfunction (ED), is a common and multidimensional sexual disorder, which comprises changes among any of the processes of the erectile response such as organic, relational, and psychological. However, both endocrine and nonendocrine causes of ED produce substantial health implications including depression and anxiety due to poor sexual performance, eventually affecting man's life eminence. Marginally invasive interventions following ED consist of lifestyle modifications, oral drugs, injections, vacuum erection devices, etc. Nevertheless, these conventional treatment regimens follow certain drawbacks such as efficacy and safety issues, and navigate to the development of novel therapeutic approaches such as nanomedicine for ED management. Nanotechnology-centred drug delivery platforms are being explored to minimize these limitations with better in vitro and in vivo effectiveness. Moreover, nanomedicine and nanocarrier-linked approaches are rapidly developing science in the nanoscale range, which contributes to site-specific delivery in a controlled manner and has generated considerable interest prominent to their potential to enhance bioavailability, decrease side effects, and avoidance of first-pass metabolism. This review provides an overview of recent discoveries regarding various nanocarriers and nano-delivery methods, along with current trends in the clinical aspects of ED. Additionally, strategies for clinical translation have been incorporated.

Emerging Trends in Bilosomes as Therapeutic Drug Delivery Systems

In recent years, there has been a notable surge in the utilization of stabilized bile acid liposomes, chemical conjugates, complexes, mixed micelles, and other drug delivery systems derived from bile acids, often referred to as bilosomes. The molecular structure and interactions of these amphiphilic compounds provide a distinctive and captivating subject for investigation. The enhanced stability of new generation bilosomes inside the gastrointestinal system results in the prevention of drug degradation and an improvement in mucosal penetration. These characteristics render bilosomes to be a prospective nanocarrier for pharmaceutical administration, prompting researchers to investigate their potential in other domains. This review paper discusses bilosomes that have emerged as a viable modality in the realm of drug delivery and have significant promise for use across several domains. Moreover, this underscores the need for additional investigation and advancement in order to comprehensively comprehend the prospective uses of bilosomes and their effectiveness in the field of pharmaceutical administration. This review study explores the current scholarly attention on bilosomes as prospective carriers for drug delivery. Therapeutic areas where bilosomes have shown outstanding performance in terms of drug delivery are outlined in the graphical abstract.

Bioavailability enhancement of sildenafil citrate via hydrogel-forming microneedle strategy in combination with cyclodextrin complexation

Sildenafil citrate (SIL) as a first-line treatment for erectile dysfunction is currently reported to have poor solubility and bioavailability. Moreover, SIL undergoes first-pass metabolism when taken orally and its injection can lead to discomfort. In this study, we introduce a novel transdermal delivery system that integrates hydrogel-forming microneedles with the inclusion complex tablet reservoir. The hydrogel-forming microneedle was prepared from a mixture of polymers and crosslinkers through a crosslinking process. Importantly, the formulations showed high swelling capacity (>400 %) and exhibited adequate mechanical and penetration properties (needle height reduction < 10 %), penetrating up to five layers of Parafilm® M (assessed to reach the dermis layer). Furthermore, to improve the solubility of SIL in the reservoir, the SIL was pre-complexed with β-cyclodextrin. Molecular docking analysis showed that SIL was successfully encapsulated into the β-cyclodextrin cavity and was the most suitable conformation compared to other CD derivatives. Moreover, to maximize SIL delivery, sodium starch glycolate was also added to the reservoir formulation. As a proof of concept, in vivo studies demonstrated the effectiveness of this concept, resulting in a significant increase in AUC (area under the curve) compared to that obtained after administration of pure SIL oral suspension, inclusion complex, and Viagra® with relative bioavailability > 100 %. Therefore, the approach developed in this study could potentially increase the efficacy of SIL in treating erectile dysfunction by being non-invasive, safe, avoiding first-pass metabolism, and increasing drug bioavailability.

Novel Vesicular Bilosomal Delivery Systems for Dermal/Transdermal Applications

The application of therapeutically active molecules through the dermal/transdermal route into the skin has evolved as an attractive formulation strategy in comparison to oral delivery systems for the treatment of various disease conditions. However, the delivery of drugs across the skin is limited due to poor permeability. Dermal/transdermal delivery is associated with ease of accessibility, enhanced safety, better patient compliance, and reduced variability in plasma drug concentrations. It has the ability to bypass the first-pass metabolism, which ultimately results in steady and sustained drug levels in the systemic circulation. Vesicular drug delivery systems, including bilosomes, have gained significant interest due to their colloidal nature, improved drug solubility, absorption, and bioavailability with prolonged circulation time for a large number of new drug molecules. Bilosomes are novel lipid vesicular nanocarriers comprising bile salts, such as deoxycholic acid, sodium cholate, deoxycholate, taurocholate, glycocholate or sorbitan tristearate. These bilosomes are associated with high flexibility, deformability, and elasticity attributed to their bile acid component. These carriers are advantageous in terms of improved skin permeation, increased dermal and epidermal drug concentration, and enhanced local action with reduced systemic absorption of the drug, resulting in reduced side effects. The present article provides a comprehensive overview of the biopharmaceutical aspects of dermal/transdermal bilosome delivery systems, their composition, formulation techniques, characterization methods, and applications.

Liposomes encapsulation by pH driven improves the stability, bioaccessibility and bioavailability of urolithin A: A comparative study

Urolithin A (UroA) is gut metabolites of ellagitannins possessing a vast range of biological activities, but its poor water solubility and low bioavailability hinder its potential applications. This study utilized the pH dependent dissolution characteristics of UroA and employed a simple pH-driven method to load UroA into liposomes. The characterization and stability of obtained liposomes under different conditions were evaluated, and their oral bioavailability was tested by pharmacokinetics, and compared with UroA liposomes prepared using traditional thin film dispersion (TFM-ULs). Results indicated that liposomes could effectively encapsulate UroA. The UroA liposomes prepared by the pH-driven method (PDM-ULs) showed lower particle size, polydispersity index, zeta potential, and higher encapsulation efficiency than TFM-ULs. Interestingly, better thermal stability, storage stability, in vitro digestion stability, and higher bioaccessibility were also found on PDM-ULs. Moreover, pharmacokinetic experiments in rats demonstrated that PDM-ULs could significantly improve the bioavailability of UroA, with an absorption efficiency 1.91 times that of TFM-ULs. Therefore, our findings suggest that liposomes prepared by pH-driven methods have great potential in improving the stability and bioavailability of UroA.

Breaking barriers: bilosomes gel potentials to pave the way for transdermal breast cancer treatment with Tamoxifen

OBJECTIVE

Breast cancer affects women globally, regardless of age or location. On the other hand, Tamoxifen (TXN), a class II biopharmaceutical drug is acting as a prophylactic/treating agent for women at risk of and/or with hormone receptor-positive breast cancer. However, its oral administration has life-threatening side effects, which have led researchers to investigate alternative delivery methods. One such method is transdermal drug delivery utilizing bile salts as penetration enhancers, aka Bilosomes.

METHODS

Bilosomes formulations were optimized statistically for the outcome of vesicle shape, size, and entrapment efficiency using two types of bile, i.e. sodium taurocholate and sodium cholate. These bilosomes were then loaded into HPMC base gel and further characterized for their morphology, drug content, pH, viscosity, spreadability and eventually ex-vivo skin penetration and deposition studies.

RESULTS

Findings showed that sodium cholate has superiority as a penetration enhancer over sodium taurocholate in terms of morphological characterizes, zeta potential, and cumulative amounts of tamoxifen permeated per unit area (15.13 ± 0.71 μg/cm2 and 6.51 ± 0.6 μg/cm2 respectively). In fact, bilosomes designed with sodium cholate provided around 9 folds of skin deposition compared to TXN non-bilosomal gel.

CONCLUSION

Bilosomes gels could be a promising option for locally delivering tamoxifen to the breast through the skin, offering an encouraging transdermal solution.

Exploring the application of sildenafil for high-fat diet-induced erectile dysfunction based on interleukin-18-mediated NLRP3/Caspase-1 signaling pathway

Background

Inflammation is a key risk factor for heart disease and has also been linked to erectile dysfunction (ED). Sildenafil is a phosphodiesterase type 5 inhibitor with a strong antioxidant effect. Interleukin (IL)-18 is a proinflammatory factor. Excessive production and release of IL-18 disrupt the balance between IL-18 and IL-18 binding proteins in certain inflammatory diseases, leading to the occurrence of pathological inflammation.

Aim

We evaluated the effects of sildenafil on erectile function in a rat model of high-fat diet-induced ED.

Methods

Male Sprague Dawley rats (6 weeks old) were divided into 5 groups: control, ED, sildenafil, IL-18, and IL-18 + sildenafil. Subsequently, intracavernous pressure and mean arterial pressure were used to assess the erectile function of these rats. The expression of endothelial nitric oxide synthase, pyroptosis factors, and the ratio of smooth muscle cells and collagen fibers were evaluated in the serum and corpora tissue.

Outcomes

Exploring the role and mechanism of sildenafil in ED through NLRP3-mediated pyroptosis pathway.

Results

In comparison to the ED and IL-18 groups, there were statistically significant increases in the ratio of intracavernous pressure to mean arterial pressure, endothelial nitric oxide synthase expression, and the ratio of smooth muscle cells to collagen fibers following sildenafil intervention (P < .05). The sildenafil group and IL-18 + sildenafil group also showed statistically significant decreases the expression of NLRP3, caspase-1, and gasdermin D (P < .05).

Clinical Implications

Sildenafil can improve erectile dysfunction by inhibiting inflammation.

Strengths and Limitations

Strengths are that the relationship between pyroptosis and ED has been verified through in vitro and in vivo experiments. The limitation is that the conclusions drawn from animal and cells experiments need to be confirmed in clinical research.

Conclusion

Sildenafil may reduce the effect of IL-18-induced inflammation in high-fat diet-induced ED rats through NLRP3/caspase-1 pyroptosis pathway.

Hydrogel forming microneedle-mediated transdermal delivery of sildenafil citrate from polyethylene glycol reservoir: An ex vivo proof of concept study

Erectile dysfunction (ED) is a disorder that often occurs in men worldwide. One of the drugs used as the first-line therapy for erectile dysfunction is sildenafil citrate (SC). Unfortunately, SC was commonly found in oral, injection, and transdermal dosage forms with some limitations, mainly related to low oral bioavailability caused by the occurrence of first-pass metabolism in the liver, and poor patient comfort and compliance. Therefore, it was essential to develop dosage forms to overcome these limitations. We developed hydrogel-forming microneedles (HFM) that can facilitate transdermal delivery of SC by penetrating the stratum corneum. HFM was made using polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) as polymers and several variations of tartaric acid as crosslinking agents. The evaluation of swelling properties, mechanical resistance, and penetration ability showed that the HFM produced had good insertion properties and swelling capabilities ranging from 300% to 700%. This HFM was designed to be integrated with a polyethylene glycol (PEG) reservoir prepared using several types of PEG with different molecular weights. The ex vivo permeation study showed that up to 80% of SC (equivalent to 20.2 ± 0.29 mg/mL) was delivered transdermally from this combined dosage form. For the first time, SC has been successfully developed into an HFM that was integrated with a PEG reservoir which was non-irritating, safe, and painless. It also had promising results for increasing the effectiveness of ED therapy.

Novel Siprulina platensis Bilosomes for Combating UVB Induced Skin Damage

The recent interest in bioactive compounds from natural sources has led to the evolution of the skin care industry. Efforts to develop biologically active ingredients from natural sources have resulted in the emergence of enhanced skin care products. Spirulina (SPR), a nutritionally enriched cyanobacteria-type microalga, is rich in nutrients and phytochemicals. SPR possesses antioxidant, immunomodulatory, and anti-inflammatory activities. Spirulina-loaded bilosomes (SPR-BS), a novel antiaging drug delivery system, were designed for the first time by incorporation in a lecithin−bile salt-integrated system for bypassing skin delivery obstacles. The optimized BS had good entrapment efficiency, small particle size, optimal zeta potential, and sustained drug release pattern. Blank and SPR-loaded BS formulations were safe, with a primary irritancy index of <2 based on the Draize test. In vivo tests were conducted, and photoprotective antiaging effects were evaluated visually and biochemically by analyzing antioxidant, anti-inflammatory, and anti-wrinkling markers following ultraviolet (UV) B irradiation. Results of biochemical marker analysis and histopathological examination confirmed the superior antiaging effect of SPR-BS compared with SPR. Thus, SPR-loaded BS is a promising nanoplatform for SPR delivery, can be used for treating UV-induced skin damage, and offers maximum therapeutic outcomes.

Prostaglandins as a Topical Therapy for Erectile Dysfunction: A Comprehensive Review

INTRODUCTION

Erectile dysfunction (ED) is a substantial cause of dissatisfaction among many men. This discontentment has led to the emergence of various drug treatment options for this problem.

OBJECTIVES

Unfortunately, due to various interactions, contraindications, and side effects, systemic therapies such as phosphodiesterase-5 inhibitors (including sildenafil, tadalafil, vardenafil, avanafil, etc.) are not welcomed in many patients. These problems have led researchers to look for other ways to reduce these complications.

METHODS

This article holistically reviews the efficacy of topical prostaglandins and their role in treating ED. We sought to provide a comprehensive overview of recent findings on the current topic by using the extensive literature search to identify the latest scientific reports on the topic.

RESULTS

In this regard, topical and transdermal treatments can be suitable alternatives. In diverse studies, prostaglandins, remarkably PGE1 (also known as alprostadil), have been suggested to be an acceptable candidate for topical treatment.

CONCLUSION

Numerous formulations of PGE1 have been used to treat patients so far. Still, in general, with the evolution of classical formulation methods toward modern techniques (such as using nanocarriers and skin permeability enhancers), the probability of treatment success also increases.

A Brain-Targeted Approach to Ameliorate Memory Disorders in a Sporadic Alzheimer's Disease Mouse Model via Intranasal Luteolin-Loaded Nanobilosomes

Impaired memory and cognitive function are the main features of Alzheimer's disease (AD). Unfortunately, currently available treatments cannot cure or delay AD progression. Moreover, the blood-brain barrier hampers effective delivery of treatment to the brain. Therefore, we aimed to evaluate the impact of intranasally delivered luteolin on AD using bile-salt-based nano-vesicles (bilosomes). Different bilosomes were prepared using 23-factorial design. The variables were defined by the concentration of surfactant, the molar ratio of cholesterol:phospholipid, and the concentration of bile salt. Results demonstrated optimized luteolin-loaded bilosomes with particle size (153.2 ± 0.98 nm), zeta potential (-42.8 ± 0.24 mV), entrapment efficiency% (70.4 ± 0.77%), and % drug released after 8 h (80.0 ± 1.10%). In vivo experiments were conducted on an AD mouse model via intracerebroventricular injection of 3 mg/kg streptozotocin. We conducted behavioral, biochemical marker, histological, and immune histochemistry assays after administering a luteolin suspension or luteolin bilosomes (50 mg/kg) intranasally for 21 consecutive days. Luteolin bilosomes improved short-term and long-term spatial memory. They also exhibited antioxidant properties and reduced levels of proinflammatory mediators. They also suppressed both amyloid β aggregation and hyperphosphorylated Tau protein levels in the hippocampus. In conclusion, luteolin bilosomes are an effective, safe, and non-invasive approach with superior cognitive function capabilities compared to luteolin suspension.

The upregulation of tryptophan hydroxylase-2 expression is important for premature ejaculation treatment with the selective serotonin reuptake inhibitor

BACKGROUND

Although there was some evidence to suggest that the serotonergic system in the brain played an important role in premature ejaculation (PE), tryptophan hydroxylase-2 (TPH2) is considered to be the key enzyme for the synthesis of 5-hydroxytryptamine (5-HT) and few studies have reported that brain TPH2 is involved in the regulation of ejaculation.

OBJECTIVES

This study aimed to investigate whether changes in brain TPH2 levels were associated with PE and to explore the effects of acute administration of dapoxetine on TPH2 expression in the brain of rats with rapid ejaculation.

MATERIALS AND METHODS

Based on the ejaculation frequency, the male rats were split into three groups: "rapid," "normal," and "sluggish" ejaculators. The level of 5-HT in the brain was determined by an enzyme-linked immunosorbent assay. TPH2 expression was detected by western blot analysis and immunohistochemistry.

RESULTS

The results showed that the concentration of 5-HT and the expression of TPH2 in rapid rats were the lowest, while those in sluggish rats were the highest. Correlation analysis also indicated the level of TPH2 was positively correlated with ejaculation latency (r = 0.8633, p < 0.0001) and negatively correlated with ejaculation frequency (r = -0.874, p < 0.001). In addition, dapoxetine acute administration to rapid rats resulted in upregulation of TPH2 expression in the brain.

DISCUSSION

There was an important link between the level of TPH2 and the change of ejaculation behaviors. Decreased expression of TPH2 in relevant brain regions will lead to rapid ejaculation. Moreover, the effect of dapoxetine on prolonging ejaculation may be due to the upregulation of TPH2 expression.

CONCLUSION

We found the correlation between the level of TPH2 in the brain and PE. The findings in this study will open up a novel way for future research in PE therapy.

Intranasal Zolmitriptan-Loaded Bilosomes with Extended Nasal Mucociliary Transit Time for Direct Nose to Brain Delivery

This study aimed at delivering intranasal zolmitriptan directly to the brain through preparation of bilosomes incorporated into a mucoadhesive in situ gel with extended nasal mucociliary transit time. Zolmitriptan-loaded bilosomes were constructed through a thin film hydration method applying Box-Behnken design. The independent variables were amount of sodium deoxycholate and the amount and molar ratio of cholesterol/Span® 40 mixture. Bilosomes were assessed for their entrapment efficiency, particle size and in vitro release. The optimal bilosomes were loaded into mucoadhesive in situ gel consisting of poloxamer 407 and hydroxypropyl methylcellulose. The systemic and brain kinetics of Zolmitriptan were evaluated in rats by comparing intranasal administration of prepared gel to an IV solution. Statistical analysis suggested an optimized bilosomal formulation composition of sodium deoxycholate (5 mg) with an amount and molar ratio of cholesterol/Span® 40 mixture of 255 mg and 1:7.7, respectively. The mucoadhesive in situ gel containing bilosomal formulation had a sol-gel temperature of 34.03 °C and an extended mucociliary transit time of 22.36 min. The gelling system possessed enhanced brain bioavailability compared to bilosomal dispersion (1176.98 vs. 835.77%, respectively) following intranasal administration. The gel revealed successful brain targeting with improved drug targeting efficiency and direct transport percentage indices. The intranasal delivery of mucoadhesive in situ gel containing zolmitriptan-loaded bilosomes offered direct nose-to-brain drug targeting with enhanced brain bioavailability.

Bilosomes as effective delivery systems to improve the gastrointestinal stability and bioavailability of epigallocatechin gallate (EGCG)

Epigallocatechin gallate (EGCG) has a variety of biological activities, but exhibits poor stability and low bioavailability. In this study, EGCG bilosome was prepared and characterized, and its stability during different storage conditions (pH, NaCl concentration, and temperature) and in gastrointestinal fluid was evaluated and compared with liposomes and niosomes. Among them, EGCG niosomes had the highest pH stability, and the existence of sodium cholate reduced the stability of bilosomes in acidic medium. EGCG stability was significantly increased in the presence of salt ions (0-100 mM NaCl) and under different temperatures (25 °C, 37 °C) when delivered as niosomes and bilosomes. Retention rate of EGCG in bilosomes was 71.64 ± 4.05% after incubation in simulated intestinal fluid for 2 h, which was significantly higher than retention rate of EGCG liposomes (24.02 ± 3.95%) and niosomes (55.74 ± 6.85%), thus indicating greater gastrointestinal stability of EGCG bilosomes. Furthermore, bioavailability of EGCG encapsulated in bilosomes was improved by 1.98 times. Overall, these findings indicate that EGCG bilosomes, as a new delivery system, had great potential application as a means to improve stability and bioavailability of EGCG.

Novel rhein integrate transphytosomes as non-invasive local therapy for osteoarthritis to ameliorate cartilage deterioration in MIA-arthritic rats

Rhein (RH), a natural chondroprotective agent, suffers from poor systemic availability (20-25%) after oral administration concomitant to side effects on the gastrointestinal tract and liver. We present a new approach for non-invasive local targeted delivery of rhein to ameliorate cartilage deterioration employing cartilage-homing phospholipids nanocarriers. This is the first work to elaborate RH loaded transphytosome (RH-T-PHY) as novel nanovesicular systems for transdermal drug delivery based on an advantageous hybrid between phytosomes and transfersomes or bilosomes. Here, we developed transphytosomes through incorporating various edge activators (EAs) such as Tween 80, Span 80 and sodium deoxycholate into the lipid bilayer of RH phytosomes to affix the flexibility. RH-T-PHY with high flexibility and entrapment efficacy showed the highest significant skin permeation compared to conventional phytosomes. Additionally, RH-T-PHY have a magnificent potential in maintaining high chondroprotective activity as demonstrated by enhanced repair, regeneration of chondrocytes and GAG formation in MIA-induced osteoarthritis (OA) rat model. Besides, histological examination of vital organs revealed the formulation safety. Confocal laser microscopy images revealed the highest drug availability in the articular cartilage of RH-T-PHY treated group. Conclusively, novel RH-T-PHY can serve as a promising alternative means for delivery of chondroprotective drugs for effective non-invasive local therapy of OA.