Bilosomes as a promising nanoplatform for oral delivery of an alkaloid nutraceutical:improved pharmacokinetic profile and snowballed hypoglycemic effect in diabetic rats

Diabetes mellitus is a life-threatening metabolic disease. At the moment, there is no effective treatment available to combat it. In this study, we aimed to develop berberine-loaded bilosomes (BER-BLS) to boost the oral bioavailability and therapeutic efficacy of berberine, a natural antidiabetic medication. The BER-BLS was fabricated using a thin-film hydration strategy and optimized using a central composite design (face-centered). The average vesicle size, entrapment efficiency, and surface charge of the optimized BER-BLS preparation were 196.5 nm, 89.7%, (−) 36.4 mV, respectively. In addition, it exhibited higher stability and better-sustained release of berberine than the berberine solution (BER-SOL). BER-BLS and BER-SOL were administered to streptozocin-induced diabetic rats. The optimized BER-BLS formulation had a significant hypoglycemic impact, with a maximum blood glucose decrease of 41%, whereas BER-SOL only reduced blood glucose by 19%. Furthermore, the pharmacological effect of oral BER-BLS and BER-SOL corresponded to 99.3% and 31.7%, respectively, when compared to subcutaneous insulin (1 IU). A pharmacokinetic analysis found a 6.4-fold rise in the relative bioavailability of berberine in BER-BLS when compared to BER-SOL at a dosage of 100 mg/kg body weight. Histopathological investigation revealed that BER-BLS is suitable for oral administration. Our data demonstrate that BLS is a potential nanocarrier for berberine administration, enhancing its oral bioavailability and antidiabetic activity

Cholesterol level affects surface charge of lipid membranes in saline solution

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Neuroprotective effect of ranolazine improves behavioral discrepancies in a rat model of scopolamine-induced dementia

BackgroundRanolazine (Rn), an antianginal agent, acts in the central nervous system and has been used as a potential treatment agent for pain and epileptic disorders. Alzheimer’s disease (AD) is one of the most prevalent neurodegenerative diseases and the leading factor in dementia in the elderly.AimWe examined the impact of Rn on scopolamine (Sco)-induced dementia in rats.MethodsThirty-two albino male rats were divided into four groups: control, Rn, Sco, and Rn + Sco.ResultsA significant decrease in the escape latency in the Morris water maze test after pre-treatment with Rn explained better learning and memory in rats. Additionally, Rn significantly upregulated the activities of the antioxidant enzymes in the treated group compared to the Sco group but substantially reduced acetylcholinesterase activity levels in the hippocampus. Moreover, Rn dramatically reduced interleukin-1 β (IL-1β) and IL-6 and upregulated the gene expression of brain-derived neurotrophic factor (BDNF). Furthermore, in the Sco group, the hippocampal tissue’s immunohistochemical reaction of Tau and glial factor activating protein (GFAP) was significantly increased in addition to the upregulation of the Caspase-3 gene expression, which was markedly improved by pre-treatment with Rn. The majority of pyramidal neurons had large vesicular nuclei with prominent nucleoli and appeared to be more or less normal, reflecting the all-beneficial effects of Rn when the hippocampal tissue was examined under a microscope.ConclusionOur findings indicated that Rn, through its antioxidative, anti-inflammatory, and anti-apoptotic effects, as well as the control of the expression of GFAP, BDNF, and Tau proteins, has a novel neuroprotective impact against scopolamine-induced dementia in rats

Funktionelle Untersuchungen zur Histidinkinase CaNik1p von Candida albicans

CaNik1p is a group III HK of the most frequent human fungal pathogen Candida albicans. The relevance of this group of enzymes for fungicidal activity was shown by the construction of Saccharomyces cerevisiae transformants, in which CaNik1p and other group III HKs were expressed. To investigate the role of different domains of CaNik1p for fungicidal activity, wild-type and mutated variants of CaNIK1 were constructed and heterologously expressed in S. cerevisiae. We could show for the first time a direct interaction between fludioxonil and CaNik1p, an example of group III HKs. The yeast strains, which expressed variants of the protein, which were mutated in the conserved HisKA, HATPase_c and REC domains, showed complete loss of sensitivity against the tested antifungals. The sensitivity to antifungals correlated with the phosphorylation state of the MAP kinase Hog1p after treatment with fludioxonil. However, fludioxonil did not interfere with the histidine kinase activity of the protein as revealed from in vitro kinase assays using the purified protein and monitoring ATP consumption or autophosphorylation of the protein. Group III HKs are characterized by consecutive HAMP domains in the N-terminal part of the protein. As the function of these domains is largely unknown, we deleted them from the protein. Expression of CaNik1p?HAMP led to growth inhibition of the transformed S. cerevisiae that correlated with constitutive phosphorylation of Hog1p. This could be reversed by additional point mutation in the conserved His510 of the HisKA domain or by expression in S. cerevisiae single gene deletion mutants of the response regulator SSK1 or one of the components of theHog1MAPK module. In conclusion, treatment with antifungals and deletion of HAMP domains led to severe growth inhibition, which correlated with the activation of the MAP kinase Hog1, and for which the functionalities of the conserved domainsof the HK CaNik1p were essential.CaNik1p ist eine Histidinkinase (HK) der Gruppe III aus dem humanpathogenen Pilz Candida albicans. Die Relevanz dieser Enzymgruppe für die Wirkung von Fungiziden wurde durch die Herstellung von Saccharomyces cerevisiae – Transformanten gezeigt, in denen CaNik1p und andere Gruppe III HKs exprimiert wurden. Um die Rolle von verschiedenen Domänen von CaNik1p für die fungizide Wirkung zu untersuchen, wurden Punktmutationen in den konservierten Domänen HisKA, HATPase_c und REC eingeführt. Mit dem rekombinant hergestellten, aufgereinigten Protein CaNik1p konnten wir diese Wechselwirkung mit dem Wirkstoff Fludioxonil über Sättigungstransferdifferenz-NMR erstmals zeigen. Außerdem erwiesen sich die Transformanten, die die mutierten Proteine exprimierten, als resistent gegen die Fungizide. Die Sensitivität gegenüber Fungiziden korrelierte mit dem Phosphorylierungszustandder MAP kinase Hog1p nach Behandlung mit Fludioxonil. Fludioxonil inhibierte jedoch die Kinaseaktivität des Proteins nicht, wie wir durch In-vitro Kinaseaktivitätstests mit dem gereinigten Protein zeigen konnten. Die Kinaseaktivität konnte selbst in den Proteinmutanten noch nachgewiesen werden. Gruppe III HK sind durch eine Abfolge von HAMP Domänen im N-terminalen Bereich der Proteine charakterisiert. Da die Funktion dieser Domänen noch weitgehend unverstanden ist, entfernten wir sie aus dem Protein. Die Expression dieses verkürzten Proteins CaNik1pDHAMP führte zur Wachstumshemmung der S. cerevisiae-Transformante, was mit der konstitutiven Phosphorylierung von Hog1 korrelierte.Durch zusätzliche Punktmutation in der HisKA-Domäne(H510Q) oder durch Expression in S. cerevisiae Mutanten, in denen einzelne Gene des HOG-Signalweges deletiert waren, konnte dieser Effekt aufgehoben werden. Die Behandlung mit Fungiziden und die Deletion der HAMP Domänen führten zur Reduktion des Wachstums, für die die Funktionalität der konservierten Proteindomänen essentiell war

Spironolactone-Loaded LeciPlexes as Potential Topical Delivery Systems for Female Acne: In Vitro Appraisal and Ex Vivo Skin Permeability Studies

Spironolactone (SP), an aldosterone antagonist with anti-androgen properties, has shown promising results in the treatment of female acne. However, its systemic side effects limit its clinical benefits. This study aimed to prepare and evaluate LeciPlexes for SP topical delivery. LeciPlexes were prepared by a one-step procedure and characterized using various techniques. Optimum LeciPlex preparation was incorporated into 1% methylcellulose gel and SP permeability was tested ex vivo in Sprague-Dawley rat skin. The maximum drug encapsulation efficiency obtained was 93.6 ± 6.9% and was dependent on the drug/phospholipid and surfactant/phospholipid ratios. A zeta potential of +49.3 ± 3.5 to +57.7 ± 3.3 mV and a size of 108 ± 25.3 to 668.5 ± 120.3 nm were observed for the LeciPlexes. FT-IR and DSC studies confirmed the incorporation of SP into the LeciPlexes through hydrophobic and hydrogen bonding interactions. SP release from the LeciPlex formulations was significantly slower than from the drug suspension. Cumulative SP permeated through rat skin from LeciPlex gel was about 2-fold higher than SP control gel. Cumulative SP deposited in the stratum corneum and other skin layers from the LeciPlex gel was about 1.8- and 2.6-fold higher than SP control gel, respectively. This new SP LeciPlex formulation is a promising carrier for the treatment of female acne

Atorvastatin-loaded nanostructured lipid carriers (NLCs): strategy to overcome oral delivery drawbacks

Atorvastatin (AT) is a widely used lipid-regulating drug to reduce cholesterol and triglycerides. Its poor aqueous solubility and hepatic metabolism require development of drug delivery systems able to improve its solubility and bypass hepatic effect. For this purpose, atorvastatin nanostructured lipid carriers (AT-NLCs) were prepared and characterized. AT-NLCs were prepared by emulsification using high-speed homogenization followed by ultrasonication. The prepared NLCs showed particle size between 162.5 ± 12 and 865.55 ± 28 nm while zeta potential values varied between −34 ± 0.29 and −23 ± 0.36 mV. They also showed high encapsulation efficiency (>87%) and amorphous state of the drug in lipid matrix. Pharmacokinetic parameters of optimized formulation (NLC-1; composed of 2% Gelucire® 43/01, 8% Capryol® PGMC, 2% Pluronic®F68 and 0.5% lecithin) revealed 3.6- and 2.1-fold increase in bioavailability as compared to atorvastatin suspension and commercial product (Lipitor®), respectively. Administration of NLC-1 led to significant reduction (p < .05) in the rats’ serum levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL) and significant increase in high-density lipoprotein (HDL). This improvement was confirmed histologically by minimizing the associated hepatic steatosis. These investigations demonstrated the superiority of NLCs for improvement of oral bioavailability and in vivo performance of AT

Influence of Stabilizer on the Development of Luteolin Nanosuspension for Cutaneous Delivery: An In Vitro and In Vivo Evaluation

Luteolin is a natural drug used as an antioxidant and anti-inflammatory, but unfortunately, it possesses low water solubility, which hinders its delivery via the skin. The main objective of this study was to prepare a luteolin-loaded nanosuspension by the antisolvent precipitation/sonication technique and study the effects of four stabilizers (two nonionic stabilizers, Pluronic F127 and Tween 80, and two polymeric stabilizers, HPMC and alginate) on the physicochemical properties of the prepared formulations. The selected formulations were incorporated into a gel base to evaluate their skin permeability and anti-inflammatory efficacy. The particle size was in the nanosize range (in the range from 468.1 ± 18.6 nm to 1024.8 ± 15.9 nm), while the zeta potential was negative and in the range from −41.7 ± 6.3 mV to −15.3 ± 1.9 mV. In particular, alginate-stabilized nanosuspensions showed the smallest particle size, the highest zeta potential value, and excellent stability due to the dual stabilizing effects (electrostatic and steric effects). The DSC results revealed a less crystalline structure of luteolin in lyophilized NS2 and NS12. Formulations stabilized by 1% Pluronic (NS2) and 2% alginate (NS12) were incorporated into a carbopol 940 gel base and showed good organoleptic character (homogenous with no evidenced phase separation or grittiness). In vitro dissolution studies showed that NS12 enhanced luteolin release rates, indicating the effect of particle size on the drug release pattern. On the other hand, NS2 showed enhanced skin permeability and anti-inflammatory effect in a carrageenan-induced paw edema model, revealing the surface activity role of the stabilizers. In conclusion, while alginate increased the nanosuspension stability by means of dual stabilizing effects, Pluronic F127 improved the skin delivery and pharmacodynamic efficacy of luteolin

Influence of Stabilizer on the Development of Luteolin Nanosuspension for Cutaneous Delivery: An In Vitro and In Vivo Evaluation

Luteolin is a natural drug used as an antioxidant and anti-inflammatory, but unfortunately, it possesses low water solubility, which hinders its delivery via the skin. The main objective of this study was to prepare a luteolin-loaded nanosuspension by the antisolvent precipitation/sonication technique and study the effects of four stabilizers (two nonionic stabilizers, Pluronic F127 and Tween 80, and two polymeric stabilizers, HPMC and alginate) on the physicochemical properties of the prepared formulations. The selected formulations were incorporated into a gel base to evaluate their skin permeability and anti-inflammatory efficacy. The particle size was in the nanosize range (in the range from 468.1 ± 18.6 nm to 1024.8 ± 15.9 nm), while the zeta potential was negative and in the range from −41.7 ± 6.3 mV to −15.3 ± 1.9 mV. In particular, alginate-stabilized nanosuspensions showed the smallest particle size, the highest zeta potential value, and excellent stability due to the dual stabilizing effects (electrostatic and steric effects). The DSC results revealed a less crystalline structure of luteolin in lyophilized NS2 and NS12. Formulations stabilized by 1% Pluronic (NS2) and 2% alginate (NS12) were incorporated into a carbopol 940 gel base and showed good organoleptic character (homogenous with no evidenced phase separation or grittiness). In vitro dissolution studies showed that NS12 enhanced luteolin release rates, indicating the effect of particle size on the drug release pattern. On the other hand, NS2 showed enhanced skin permeability and anti-inflammatory effect in a carrageenan-induced paw edema model, revealing the surface activity role of the stabilizers. In conclusion, while alginate increased the nanosuspension stability by means of dual stabilizing effects, Pluronic F127 improved the skin delivery and pharmacodynamic efficacy of luteolin

Long-Acting Paliperidone Parenteral Formulations Based on Polycaprolactone Nanoparticles; the Influence of Stabilizer and Chitosan on In Vitro Release, Protein Adsorption, and Cytotoxicity

Long-acting preparations containing the antipsychotic paliperidone for intramuscular injection has drawn considerable attention to achieve harmless long-term treatment. This study aimed to develop paliperidone loaded polycaprolactone (PCL) nanoparticles and investigate the influence of PCL/drug ratio, stabilizer type, and chitosan coating on physicochemical properties, protein adsorption, and cellular toxicity. Results showed that chitosan coating produced enlarged particle sizes, shifted the surface charges from negative into positive and did not influence encapsulation efficiencies. Chitosan coating relatively sustained the drug release especially in pluronic stabilized formulations. Pluronic F127 based formulations exhibited the least protein adsorption (384.3 &mu;g/mL). Chitosan coating of Tween 80 and polyvinyl alcohol stabilized formulations significantly (p &lt; 0.05) increased protein adsorption. Cellular viability was concentration-dependent and negatively affected by stabilizers. All formulations did not show cellular death at 1.56 &mu;g/mL. Inflammatory responses and oxidative stress were less affected by Tween 80 compared with other stabilizers. Chitosan minimized all aspects of cellular toxicity. Collectively, stabilizer type and chitosan coating play critical roles in developing safe and effective long-acting PCL nanoparticles intended for parenteral drug delivery. The coated formulations containing Tween 80 and Pluronic F127 as stabilizers are warranted a future in vivo study to delineate its safety and efficacy profiles

Polymeric nanoparticles based topical gel of poorly soluble drug: Formulation, ex-vivo and in vivo evaluation

The study was conducted to evaluate the potential application of nanocapsules and nanospheres as topical drug delivery systems for indomethacin (as model drug). Both were prepared by nanoprecipitation using poly (ɛ-caprolactone) and hydroxypropyl β-cyclodextrin polymers and evaluated for morphology, particle size, zeta potential, EE% and in vitro drug release then incorporated in methylcellulose and Carbopol 940 gel bases and evaluated for in vitro release. The selected formulations and market product were evaluated for ex vivo human skin permeation and anti-inflammatory and analgesic activities by paw edema and hot plate methods respectively. Results showed that nanocapsules had slight higher EE% and larger particle sizes than nanospheres. In vitro release and zeta potential were nearly similar. Methylcellulose exhibited higher in vitro release than Carbopol 940 after 3 h (except NS2). Ex vivo skin permeation studies showed significant higher cumulative amount of IND (and flux) from NC1/MC and NS1/MC (1573.06 ± 14.23 µg/cm2 and 1452.24 ± 23.18 µg/cm2 respectively) than market product. They also showed enhancement ratio and permeability coefficient rate of ∼1.5 and ∼2 respectively. NC1/MC proved to be significantly higher pharmacodynamic effects than market product. All results showed that NC1/MC could provide a promising formula as a topical delivery of indomethacin