A Novel Drug Delivery Carrier Comprised of Nimodipine Drug Solution and a Nanoemulsion: Preparation, Characterization, in vitro, and in vivo Studies

Tumor targeted cancer membrane-camouflaged ultra-small Fe nanoparticles for enhanced collaborative apoptosis and ferroptosis in glioma

Glioma is recognized as the most common and aggressive primary brain tumor in adults. Owing to the occurrence of drug resistance and the failure of drug to penetrate the blood-brain barrier (BBB), there is no effective strategy for the treatment of glioma. The main objective of this study was to develop a biomimetic glioma C6 cell membrane (C6M) derived nanovesicles (DOX-FN/C6M-NVs) loaded with doxorubicin (DOX) and ultra-small Fe nanoparticles (FN) for accomplishing the effective brain tumor-targeted delivery of DOX and improving anti-cancer efficacy via inducing collaborative apoptosis and ferroptosis. The findings revealed that employing C6M-NVs as a carrier significantly improved the therapeutic efficacy by enabling evasion of immune surveillance, facilitating targeted drug delivery to tumor sites, and minimizing cardiotoxicity and adverse effects associated with DOX. DOX-FN/C6M-NVs exhibited more potent anti-tumor effects as compared with free DOX by promoting DOX-mediated apoptosis and accelerating ferroptosis via the mediation of FN. This study suggested that DOX-FN/C6M-NVs as the potential inducer of ferroptosis and apoptosis conferred effective tumor suppression in the treatment of glioma.

Nose-to-Brain Targeting via Nanoemulsion: Significance and Evidence

Background: Non-invasive and patient-friendly nose-to-brain pathway is the best-suited route for brain delivery of therapeutics as it bypasses the blood–brain barrier. The intranasal pathway (olfactory and trigeminal nerves) allows the entry of various bioactive agents, delivers a wide array of hydrophilic and hydrophobic drugs, and circumvents the hepatic first-pass effect, thus targeting neurological diseases in both humans and animals. The olfactory and trigeminal nerves make a bridge between the highly vascularised nasal cavity and brain tissues for the permeation and distribution, thus presenting a direct pathway for the entry of therapeutics into the brain. Materials: This review portrays insight into recent research reports (spanning the last five years) on the nanoemulsions developed for nose-to-brain delivery of actives for the management of a myriad of neurological disorders, namely, Parkinson’s disease, Alzheimer’s, epilepsy, depression, schizophrenia, cerebral ischemia and brain tumours. The information and data are collected and compiled from more than one hundred Scopus- and PubMed-indexed articles. Conclusions: The olfactory and trigeminal pathways facilitate better biodistribution and bypass BBB issues and, thus, pose as a possible alternative route for the delivery of hydrophobic, poor absorption and enzyme degradative therapeutics. Exploring these virtues, intranasal nanoemulsions have proven to be active, non-invasiveand safe brain-targeting cargos for the alleviation of the brain and other neurodegenerative disorders.

The role of traditional herbal medicine for ischemic stroke: from bench to clinic-A critical review

BACKGROUND

Ischemic stroke (IS) is a leading cause of death and severe long-term disability worldwide. Over the past few decades, considerable progress has been made in anti-ischemic therapies. However, IS remains a tremendous challenge, with favourable clinical outcomes being generally difficult to achieve from candidate drugs in preclinical phase testing. Traditional herbal medicine (THM) has been used to treat stroke for over 2,000 years in China. In modern times, THM as an alternative and complementary therapy have been prescribed in other Asian countries and have gained increasing attention for their therapeutic effects. These millennia of clinical experience allow THM to be a promising avenue for improving clinical efficacy and accelerating drug discovery.

PURPOSE

To summarise the clinical evidence and potential mechanisms of THMs in IS.

METHODS

A comprehensive literature search was conducted in seven electronic databases, including PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, the Chinese National Knowledge Infrastructure, the VIP Information Database, the Chinese Biomedical Literature Database, and the Wanfang Database, from inception to 17 June 2022 to examine the efficacy and safety of THM for IS, and to investigate experimental studies regarding potential mechanisms.

RESULTS

THM is widely prescribed for IS alone or as adjuvant therapy. In clinical trials, THM is generally administered within 72 h of stroke onset and are continuously prescribed for over 3 months. Compared with Western medicine (WM), THM combined with routine WM can significantly improve neurological function defect scores, promote clinical total effective rate, and accelerate the recovery time of stroke with fewer adverse effects (AEs). These effects can be attributed to multiple mechanisms, mainly anti-inflammation, antioxidative stress, anti-apoptosis, brain blood barrier (BBB) modulation, inhibition of platelet activation and thrombus formation, and promotion of neurogenesis and angiogenesis.

CONCLUSIONS

THM may be a promising candidate for IS management to guide clinical applications and as a reference for drug development.

Excitatory Synaptic Transmission in Ischemic Stroke: A New Outlet for Classical Neuroprotective Strategies

Stroke is one of the leading causes of death and disability in the world, of which ischemia accounts for the majority. There is growing evidence of changes in synaptic connections and neural network functions in the brain of stroke patients. Currently, the studies on these neurobiological alterations mainly focus on the principle of glutamate excitotoxicity, and the corresponding neuroprotective strategies are limited to blocking the overactivation of ionic glutamate receptors. Nevertheless, it is disappointing that these treatments often fail because of the unspecificity and serious side effects of the tested drugs in clinical trials. Thus, in the prevention and treatment of stroke, finding and developing new targets of neuroprotective intervention is still the focus and goal of research in this field. In this review, we focus on the whole processes of glutamatergic synaptic transmission and highlight the pathological changes underlying each link to help develop potential therapeutic strategies for ischemic brain damage. These strategies include: (1) controlling the synaptic or extra-synaptic release of glutamate, (2) selectively blocking the action of the glutamate receptor NMDAR subunit, (3) increasing glutamate metabolism, and reuptake in the brain and blood, and (4) regulating the glutamate system by GABA receptors and the microbiota–gut–brain axis. Based on these latest findings, it is expected to promote a substantial understanding of the complex glutamate signal transduction mechanism, thereby providing excellent neuroprotection research direction for human ischemic stroke (IS).

Biocompatible poly(ethylene succinate) polyester with molecular weight dependent drug release properties

In the present study, we demonstrate that well-known molecular weight-dependent solubility properties of a polymer can also be used in the field of controlled drug delivery. To prove this, poly(ethylene succinate) (PES) polyesters with polycondensation time regulated molecular weights were synthesized via catalyst-free direct polymerization in an equimolar ratio of ethylene glycol and succinic acid monomers at 185 °C. DSC and contact angle measurements revealed that increasing the molecular weight (M_w, 4.3-5.05 kDa) through the polymerization time (40-80 min) increased the thermal stability (T_m= ∼61-80 °C) and slightly the hydrophobicity (Θ_w= ∼27-41°) of the obtained aliphatic polyester. Next, this biodegradable polymer was used for the encapsulation of Ca²⁺ channel blocker Nimodipine (NIMO) to overcome the poor water solubility and enhance the bioavailability of the drug. The drug/ polymer compatibility was proved by the means of solubility (δ) and Flory-Huggins interaction (miscibility) parameters (χ). The nanoprecipitation encapsulation of NIMO into PES with increasing M_w resulted in the formation of spherical 270 ± 103 nm NIMO-loaded PES nanoparticles (NPs). Furthermore, based on the XRD measurements, the encapsulated form of NIMO-loaded PES NPs showed lower drug crystallinity, which enhanced not only the water solubility but even the water stability of the NIMO in an aqueous medium. The in-vitro drug release experiments demonstrated that the release of NIMO drug could be accelerated or even prolonged by the molecular weights of PES as well. Due to the low crystallinity of PES polyester and low particle size of the encapsulated NIMO drug led to enhance solubility and releasing process of NIMO from PES with lower M_w (4.3 kDa and 4.5 kDa) compared to pure crystalline NIMO. However, further increasing the molecular weight (5.05 kDa) was already reduced the amount of drug release that provides the prolonged therapeutic effect and enhances the bioavailability of the NIMO drug.

A thermoreversible antibacterial zeolite-based nanoparticles loaded hydrogel promotes diabetic wound healing via detrimental factor neutralization and ROS scavenging

BACKGROUND

As recovery time of diabetic wound injury is prolonged by the production of detrimental factors, including reactive oxygen species (ROS) and inflammatory cytokines, attenuating the oxidative stress and inflammatory reactions in the microenvironment of the diabetic wound site would be significant.

EXPERIMENTAL DESIGN

In our study, we prepared thermoreversible, antibacterial zeolite-based nanoparticles loaded hydrogel to promote diabetic wound healing via the neutralization of detrimental factors such as inflammatory cytokines and ROS.

RESULTS

The cerium (Ce)-doped biotype Linde type A (LTA) zeolite nanoparticles synergistically eliminated mitochondrial ROS and neutralized free inflammatory factors, thus remodeling the anti-inflammatory microenvironment of the wound and enhancing angiogenesis. Moreover, the thermoreversible hydrogel composed of Pluronic F127 and chitosan demonstrated strong haemostatic and bactericidal behavior.

CONCLUSIONS

In conclusion, the obtained thermoreversible, antibacterial, zeolite-based nanoparticles loaded hydrogels represent a multi-targeted combination therapy for diabetic wound healing.

Preparation, Characterization, and In Vitro/In Vivo Evaluation of 3-O-β-D-Galactosylated Resveratrol-Loaded Polydopamine Nanoparticles

3-O-β-D-galactosylated resveratrol (Gal-Res) was synthesized from resveratrol (Res) and 3-O-β-D-galactose (Gal) in our previous study. In order to improve the pH sensitivity and bioavailability of Gal-Res, Gal-Res nanoparticles (Gal-Res NPs) were prepared using polydopamine (PDA) as a drug carrier. The drug loading (DL %) and entrapment efficiency (EE %) of Gal-Res NPs were 46.80% and 88.06%. The average particle size, polydispersity index (PDI), and Zeta potential of Gal-Res NPs were 179.38 ± 2.83 nm, 0.129 ± 0.013, and - 28.05 ± 0.36 mV, respectively. The transmission electron microscope (TEM) showed that Gal-Res NPs had uniform spherical morphology. Compared with the fast release of raw Gal-Res, the in vitro release of Gal-Res NPs was slow and pH-sensitive. The results of the blood vessel irritation and hemolysis test demonstrated that Gal-Res NPs had good hemocompatibility. The pharmacokinetics study in rats showed that area under the curve of plasma drug concentration time (AUC_0→600) and half-life (t_1/2) of Gal-Res NPs were enhanced 1.82-fold and 2.19-fold higher than those of raw Gal-Res. The in vivo biodistribution results showed that Gal-Res NPs were more distributed in liver tissue than Gal-Res. Gal-Res NPs with high bioavailability and liver accumulation were hopeful drug delivery systems (DDS) to treat liver diseases.

Long-Acting Risperidone Dual Control System: Preparation, Characterization and Evaluation In Vitro and In Vivo

Schizophrenia, a psychiatric disorder, requires long-term treatment; however, large fluctuations in blood drug concentration increase the risk of adverse reactions. We prepared a long-term risperidone (RIS) implantation system that can stabilize RIS release and established in-vitro and in-vivo evaluation systems. Cumulative release, drug loading, and entrapment efficiency were used as evaluation indicators to evaluate the effects of different pore formers, polymer ratios, porogen concentrations, and oil–water ratios on a RIS implant (RIS-IM). We also built a mathematical model to identify the optimized formulation by stepwise regression. We also assessed the crystalline changes, residual solvents, solubility and stability after sterilization, in-vivo polymer degradation, pharmacokinetics, and tissue inflammation in the case of the optimized formulation. The surface of the optimized RIS microspheres was small and hollow with 134.4 ± 3.5 µm particle size, 1.60 SPAN, 46.7% ± 2.3% implant drug loading, and 93.4% entrapment efficiency. The in-vitro dissolution behavior of RIS-IM had zero-order kinetics and stable blood concentration; no lag time was released for over three months. Furthermore, the RIS-IM was not only non-irritating to tissues but also had good biocompatibility and product stability. Long-acting RIS-IMs with microspheres and film coatings can provide a new avenue for treating schizophrenia.

Effect of Dihydropyridine Enrichment in the Microstructure of the Palisade Layer on the Stability of Fat Nano-emulsions

Relationship between the stability of fat nano-emulsions and the incorporated drug at the molecular level are rarely known. Herein, fat nano-emulsions containing dihydropyridine drugs were prepared and the microstructure of their palisade layers were investigated.The prepared 1.0 mg/mL nimodipine nano-emulsion was found to contain 65.50% drug in the palisade layer. The increasing drug concentration led to a decrease-increase-decrease trend in centrifugal stability constant, particle size and proton nuclear magnetic resonance (¹H NMR) signal intensity of the lecithin trimethyl ammonium group in the nimodipine and felodipine nano-emulsions. The ¹H NMR spectra of test solutions including nano-emulsions suggest that increasing drugs penetrated into the palisade layer, resulting in the lecithin arrangement from loose to tight, and then from monolayer to bilayer. Nimodipine and felodipine nano-emulsions showed two valley values at concentrations of 0.15 and 0.75 mg/mL, and 0.30 and 0.90 mg/mL respectively, which indicated that the nano-emulsion has two more stable states corresponding to the tightly arranged mono- and bi-palisade layer. These two concentrations are positively correlated with lipophilicity of nimodipine and felodipine. Further, nimodipine liposomes were prepared to validate the effect of drugs on the arrangement of lecithin in the palisade layer. ¹H NMR characterizations of the liposomes showed a similar profile to that of nano-emulsions. These results demonstrated that the increasing drug concentration could cause a rearrangement of lecithin in the palisade layer, thus affecting emulsion stability.

Towards precision nanomedicine for cerebrovascular diseases with emphasis on Cerebral Cavernous Malformation (CCM)

Introduction: Cerebrovascular diseases encompass various disorders of the brain vasculature, such as ischemic/hemorrhagic strokes, aneurysms, and vascular malformations, also affecting the central nervous system leading to a large variety of transient or permanent neurological disorders. They represent major causes of mortality and long-term disability worldwide, and some of them can be inherited, including Cerebral Cavernous Malformation (CCM), an autosomal dominant cerebrovascular disease linked to mutations in CCM1/KRIT1, CCM2, or CCM3/PDCD10 genes.Areas covered: Besides marked clinical and etiological heterogeneity, some commonalities are emerging among distinct cerebrovascular diseases, including key pathogenetic roles of oxidative stress and inflammation, which are increasingly recognized as major disease hallmarks and therapeutic targets. This review provides a comprehensive overview of the different clinical features and common pathogenetic determinants of cerebrovascular diseases, highlighting major challenges, including the pressing need for new diagnostic and therapeutic strategies, and focusing on emerging innovative features and promising benefits of nanomedicine strategies for early detection and targeted treatment of such diseases.Expert opinion: Specifically, we describe and discuss the multiple physico-chemical features and unique biological advantages of nanosystems, including nanodiagnostics, nanotherapeutics, and nanotheranostics, that may help improving diagnosis and treatment of cerebrovascular diseases and neurological comorbidities, with an emphasis on CCM disease.

Rebaudioside A/TPGS mixed nanomicelles as promising nanocarriers for nimodipine ocular delivery

Nimodipine (NMD), a calcium channel blocker, has demonstrated benefits in treating glaucoma. However, its ocular therapeutic application remains limited due to its poor aqueous solubility, which restrains the development of an ophthalmic formulation. Thus, the present study aimed to formulate an NMD micelle ophthalmic solution to enhance the potential of NMD in an ocular topical formulation to treat glaucoma. The NMD micelle ophthalmic solution was formulated with nanocarriers composed of rebaudioside A and D-α-tocopheryl polyethylene glycol 1000 succinate. Spherical mixed micelles were optimized and obtained at a small micelle size 13.429 ± 0.181 nm with a narrow size distribution (polydispersity index 0.166 ± 0.023) and high encapsulation efficiency rate (99.59 ± 0.09%). Compared with free NMD, NMD in micelles had much greater in vitro membrane permeability and antioxidant activity. The NMD micelle ophthalmic solution was well tolerated in rabbit eyes. It profoundly improved the in vivo intraocular permeation of NMD, and in vivo intraocular pressure reduction and improved miosis were also observed. Accordingly, this NMD micelle ophthalmic solution might be a promising ocular formulation to treat glaucoma. Graphical abstract.