Lymphatic Uptake Research Articles

Lymphatic targeting of cilnidipine by designing and developing a nanostructured lipid carrier drug delivery system

Objective The objective of current research is to design, develop, and optimize a cilnidipine (CLN) nanostructured lipid carrier (NLC)-based drug delivery system for the effective treatment of hypertension (HT). Significance Oral administration of CLN-loaded NLC (CLN NLC) containing glyceryl monostearate (GMS) as a solid and isopropyl myristate (IPM) as a liquid lipid may show remarkable lymphatic uptake through payer patches. Methods The emulsification probe sonication technique was used followed by optimization using 32 factorial designs. Results The optimized batch showed a mean particle size of 115.4 ± 0.22 nm with encapsulation efficiency of 98.32 ± 0.23%, polydispersity index (PDI) of 0.342 ± 0.03, and zeta potential (ZP, ζ) was −60.5 ± 0.24 which indicate excellent physical stability. In vitro studies showed a controlled release of CLN NLCs. Pharmacokinetics studies determined the C max of NLCs (373.47 ± 15.1) indicates 2.3-fold enhancement compared with plain drug (160.64 ± 7.63). Pharmacodynamic studies indicated that CLN NLCs were maintaining systolic blood pressure in a controlled manner without any signs of side effects. Conclusion CLN NLCs significantly improved lymphatic delivery and proved to be effective in the treatment and management of HT. It has been proved that CLN NLCs are found to be better than any traditional CLN dosage form due to enhancement in solubility, absorption, bioavailability, intestinal permeability, avoidance of first-pass metabolism, P-glycoprotein efflux and reduction in dose-related side effects, achievement of controlled and sustained release action.

Phototheranostic LPP-QDs-IR-820 Nanocomposites for Specific NIR-II Imaging of Lymphatic and Photothermal Therapy of Cervical Tumors.

Precise theranostics of tumors is intricately linked to the early detection and monitoring of lymph nodes (LN) and metastases, making the targeted localization of LNs essential for tumor identification. However, designing LN-targeting probes remains a significant challenge due to issues such as lymphatic uptake, biocompatibility, and fluorescence stability. To address these challenges, near-infrared II (NIR-II) fluorescence probes are developed through meticulous analysis of LN physiological structure and passive targeting strategy for LN detection and tumor therapy. An LPP-QDs-IR-820 nanocomposite (NCs) is engineered, comprising the IR-820 molecules and ultrabright PbS@CdS quantum dots (QDs), which are encapsulated within a liposome-SH-mPEG2000 polymer matrix. These NCs demonstrates remarkable lymphatic enrichment, facilitating real-time tracking of LN via electrostatic repulsion and extracellular matrix effects. Importantly, the NCs exhibit negligible in vivo toxicity and high biocompatibility. The intense NIR-II fluorescence emissions of IR-820 and PbS@CdS QDs confer upon the NCs a high NIR-II fluorescence quantum yield (6%). The cervical tumors and their deep microvessels are clearly observed via NIR-II fluorescence imaging. Moreover, the photothermal properties of IR-820 enable the NCs to achieve a photothermal conversion efficiency of 36.56%, leading to effective photothermal therapy in cervical tumor mice.

Investigation of Mirabegron-loaded Nanostructured Lipid Carriers for Improved Bioabsorption: Formulation, Statistical Optimization, andIn-VivoEvaluation.

Overactive bladder (OAB) is a usual medical syndrome that affects the bladder, and Mirabegron (MBG) is preferred medicine for its control. Currently, available marketed formulations (MYRBETRIQ® granules and MYRBETRIQ® ER tablets) suffer from low bioavailability (29-35%) hampering their therapeutic effectiveness and compromising patient compliance. By creating MBG nanostructured lipid carriers (MBG-NLCs) for improved systemic availability and drug release, specifically in oral administration of OAB treatment, this study aimed to address these issues. MBG-NLCs were fabricated using a hot-melt ultrasonication technique. MBG-GMS; MBG-oleic acid interaction was assessed by in silico molecular docking. QbD relied on the concentration of Span 80 (X1) and homogenizer speed (X2) as critical material attribute (CMA) and critical process parameter (CPP) respectively, while critical quality attributes (CQA) such as particle size (Y1) and cumulative drug release at 24h (Y2) were estimated as dependent variables. 32 factorial design was utilized to investigate the interconnection in variables that are dependent and independents. Optimized MBG-NLCs with a particle size of 194.4 ± 2.25nm were suitable for lymphatic uptake. A PDI score of 0.275 ± 0.02 and zeta potential of -36.2 ± 0.721mV indicated a uniform monodisperse system with stable dispersion properties. MBG-NLCs exhibited entrapment efficiency of 77.3 ± 1.17% and a sustained release in SIF of 94.75 ± 1.60% for 24h. MBG-NLCs exhibited the Higuchi model with diffusion as a release mechanism. A pharmacokinetic study in Wistar rats exhibited a 1.67-fold higher bioavailability as compared to MBG suspension. Hence, MBG-NLCs hold promise for treating OAB by improving MBG's oral bio absorption.

Exploration of Abiraterone acetate loaded Nanostructured lipid carriers for bioavailability improvement and circumvention of fast-fed variability.

Abiraterone acetate (ABA), a biopharmaceutical class IV drug suffers from solubility and permeability pitfalls resulting in limited oral bioavailability and positive food effect, i.e. multi-fold enhancement in drug absorption in the presence of food. This poses difficulties to physicians towards the estimation of dose and dosage regimen required for efficacious therapy of prostate cancer (PCa). Nanostructured lipid carriers (NLC) have demonstrated tremendous outcomes in enhancing the oral bioavailability of various entities along with food effect attenuation. In this study, Quality by design and multivariate analysis was employed for optimization of ABA loaded NLC (ABA NLC). The optimal size, PDI and zeta potential obtained using QbD were 134.6nm, 0.163 and -15.7mV respectively. Ex vivo qualitative and quantitative intestinal permeability studies demonstrated improved traversion of NLC through the intestinal segments. In vitro dissolution profile in biorelevant fast and fed gastric and intestinal media revealed minimal differences for ABA NLC compared to ABA. In vivo pharmacokinetics was performed to decipher the efficacy of ABA NLC in mitigating the food effect of ABA. The studies demonstrated 14.51-fold and 1.94-fold improvement in oral bioavailability during fasted and fed state respectively as compared to free ABA. The absorption mechanism of ABA NLC using chylomicron flow blocking approach conveyed lymphatic uptake as the major mechanism. Cmax fast/fed ratio was 0.9758 whereas, AUC fast/fed ratio was 0.9386, which being nearly equivalent, confirmed the food effect attenuation. Therefore, the results of the study demonstrate optimal pharmacokinetics of ABA NLC and its utility in circumventing the fast fed variability.

Modeling drug transport and absorption in subcutaneous injection of monoclonal antibodies: Impact of tissue deformation, devices, and physiology

The pharmaceutical industry has experienced a remarkable increase in the use of subcutaneous injection of monoclonal antibodies (mAbs), attributed mainly to its advantages in reducing healthcare-related costs and enhancing patient compliance. Despite this growth, there is a limited understanding of how tissue mechanics, physiological parameters, and different injection devices and techniques influence the transport and absorption of the drug. In this work, we propose a high-fidelity computational model to study drug transport and absorption during and after subcutaneous injection of mAbs. Our numerical model includes large-deformation mechanics, fluid flow, drug transport, and blood and lymphatic uptake. Through this computational framework, we analyze the tissue material responses, plume dynamics, and drug absorption. We analyze different devices, injection techniques, and physiological parameters such as BMI, flow rate, and injection depth. Finally, we compare our numerical results against the experimental data from the literature.

Inter-Antibody Variability in the Clinical Pharmacokinetics of Monoclonal Antibodies Characterized Using Population Physiologically Based Pharmacokinetic Modeling.

The objective of this work was to develop a population physiologically based pharmacokinetic (popPBPK) model to characterize the variability in the clinical PK of monoclonal antibodies (mAbs) following intravenous (IV) and subcutaneous (SC) administration. An extensive literature search was conducted and clinical PK data for FDA-approved as well as non-approved mAbs were collected. Training and validation datasets of 44 and 9 mAbs exhibiting linear pharmacokinetics were used for model development. The variability in antibody PK was captured by accounting for different rate constants of pinocytosis (CLup) and intracellular degradation (kdeg) for different mAbs. Typical values for CLup and kdeg and their respective inter-antibody variabilities (ωClup, ωKdeg) were estimated to be 0.32 L/h/L and 26.1 h-1 (73% and 46%). Varied absorption profiles following SC dosing were characterized by incorporating inter-antibody variability in local degradation (kSC) and rate of lymphatic uptake (S_Lu) of mAbs. Estimates for typical kSC and S_Lu values, and ωKsc,ωS_Lu, were found to be 0.0015 h-1 and 0.54 (193%, and 49%). FDA-approved mAbs showed less local degradation (0.0014 h-1 vs. 0.0038 h-1) compared with other clinically tested mAbs, whereas no substantial differences in physiological processes involved in disposition were observed. To evaluate the generalizability of estimated PK parameters and model validation, the final popPBPK model was used to simulate the range of expected PK for mAbs following SC administration of nine different mAbs that were not used for model-building purposes. The predicted PK of all nine mAbs was within the expected range specified a priori. Thus, the popPBPK model presented here may serve as a tool to predict the clinical PK of mAbs with linear disposition before administering them to humans. The model may also support preclinical-to-clinical translation and 'first-in-human' dose determination for mAbs.

A multi-scale numerical study of monoclonal antibodies uptake by initial lymphatics after subcutaneous injection

This paper studies the transport of monoclonal antibodies through skin tissue and initial lymphatics, which impacts the pharmacokinetics of monoclonal antibodies. Our model integrates a macroscale representation of the entire skin tissue with a mesoscale model that focuses on the papillary dermis layer. Our results indicate that it takes hours for the drugs to disperse from the injection site to the papillary dermis before entering the initial lymphatics. Additionally, we observe an inhomogeneous drug distribution in the interstitial space of the papillary dermis, with higher drug concentrations near initial lymphatics and lower concentrations near blood capillaries. To validate our model, we compare our numerical simulation results with experimental data, finding a good alignment. Our parametric studies on the drug molecule properties and injection parameters suggest that a higher diffusion coefficient increases the transport and uptake rate while binding slows down these processes. Furthermore, shallower injection depths lead to faster lymphatic uptake, whereas the size of the injection plume has a minor effect on the uptake rate. These findings advance our understanding of drug transport and lymphatic absorption after subcutaneous injection, offering valuable insights for optimizing drug delivery strategies and the design of biotherapeutics.

Assessment of ex-vivo intestinal permeability and lymphatic uptake of curcumin and piperine-loaded nanostructured lipid carriers

Assessment of ex-vivo intestinal permeability and lymphatic uptake of curcumin and piperine-loaded nanostructured lipid carriers

D-α-tocopheryl polyethylene glycol succinate-decorated dual drug-loaded lipidic nanocarriers: A strategic approach for targeting lymphatic uptake and p-gp efflux modulation to enhance oral bioavailability in HIV-1 viral reservoirs

The toxicity potential and inadequate bioavailability of antiretroviral therapy restrict their effectiveness in completely eradicating HIV-1 from viral reservoirs, as the drugs encounter difficulties in accessing these reservoirs. This study presents a combinatorial d-α-tocopheryl polyethylene glycol succinate (TPGS)-decorated nano-structured lipid carrier of Etravirine (ETR) and Darunavir Ethanolate (DRVE) that was formulated, optimized, and characterized to achieve synergistic effects against HIV-1 infection. The effectiveness of the combinatorial approach was evaluated by in silico studies, and their docking score and free binding energy showed that both drugs demonstrate synergistic effects against their respective enzymes. The cellular research of ED (ETR and DRVE) in TMZ-b1 cell lines also showed that the best ratio of ETR and DRVE (1:6.5 μg/mL) produced a combined effect. The formulation, termed ED-TPGS-NLCs, underwent optimization using central composite rotational design (CCRD) through a modified emulsification process, followed by characterization based on globule size, polydispersity index (PDI), percentage entrapment efficiency, percentage drug loading, and transmission electron microscopy (TEM) analysis. In vitro release studies demonstrated a notable improvement of drug release from the optimized lipid nanosystem, conforming to the Korsmeyer-Peppas kinetics model. Besides, the in-vitro studies, the intestinal permeation enhancement study, the intestinal depth analysis, and the pharmacokinetic assessment of the optimized formulation in Wistar rats were performed to improve permeation and increase plasma drug concentration. ED-TPGS-NLCs also stopped HIV-1 infection in TMZ-b1 cell lines by 50 %, and the lowest concentration needed to do this was about 58 times lower than purified ED suspension. These studies ensure that ED-TPGS-NLCs were taken up due to the formation of chylomicrons and inhibit the p-gp efflux system by TPGS and solutol to inhibit the first-pass hepatic metabolism, which helps to improve the intestinal permeation and enhance plasma drug concentration, leading to enhanced oral bioavailability of ED. Hence, the improved bioavailability of ED in the nanoformulation also enhanced the anti-retroviral efficacy and improved the safety margins of ED-TPGS-NLCs. These findings can also reduce the side effects of high doses of antiretroviral drugs.

In Vitro Predictive Model for Intestinal Lymphatic Uptake: Exploration of Additional Enhancers and Inhibitors.

Drug absorption via chylomicrons holds significant implications for both pharmacokinetics and pharmacodynamics. However, a mechanistic understanding of predicting in vivo intestinal lymphatic uptake remains largely unexplored. This study aimed to delve into the intestinal lymphatic uptake of drugs, investigating both enhancement and inhibition using various excipients through our previously established in vitro model. It also examined the applicability of the model by assessing the lymphatic uptake enhancement of a lymphotropic formulation with linoleoyl polyoxyl-6 glycerides using the same model. The model successfully differentiated among olive, sesame, and peanut oils in terms of lymphatic uptake. However, it did not distinguish between oils containing long-chain fatty acids and coconut oil. Coconut oil, known for its abundance of medium-chain fatty acids, outperformed other oils. This heightened uptake was attributed to the superior emulsification of this oil in artificial chylomicron media due to its high content of medium-chain fatty acids. Additionally, the enhanced uptake of the tested formulation with linoleoyl polyoxyl-6 glycerides underscored the practical applicability of this model in formulation optimization. Moreover, data suggested that increasing the zeta potential of Intralipid® using sodium lauryl sulfate (SLS) and decreasing it using (+/-) chloroquine led to enhanced and reduced uptake in the in vitro model, respectively. These findings indicate the potential influence of the zeta potential on intestinal lymphatic uptake in this model, though further research is needed to explore the possible translation of this mechanism in vivo.

Nanoparticle-mediated delivery of tetrahydrobiopterin restores endothelial function in diabetic rats

Endothelial dysfunction, underlying the vascular complications of diabetes and other cardiovascular disorders, may result from uncoupling of endothelial nitric oxide synthase (eNOS) activity due to decreased levels of tetrahydrobiopterin (BH4), a critical co-factor for eNOS. Some clinical trials attempting to deliver exogenous BH4 as a potential therapeutic strategy in vascular disease states have failed due to oxidation of BH4 in the circulation. We sought to develop a means of protecting BH4 from oxidation while delivering it to dysfunctional endothelial cells. Polymeric and solid lipid nanoparticles (NPs) loaded with BH4 were delivered by injection or oral gavage, respectively, to streptozotocin-induced diabetic rats. BH4 was measured in coronary endothelial cells and endothelium-dependent vascular reactivity was assessed in vascular rings. Lymphatic uptake of orally delivered lipid NPs was verified by sampling mesenteric lymph. BH4-loaded polymeric NPs maintained nitric oxide production by cultured endothelial cells under conditions of oxidative stress. BH4-loaded NPs, delivered via injection or ingestion, increased coronary endothelial BH4 concentration and improved endothelium-dependent vasorelaxation in diabetic rats. Pharmacodynamics assessment indicated peak concentration of solid lipid NPs in the systemic bloodstream 6 hours after ingestion, with disappearance noted by 48 hours. These studies support the feasibility of utilizing NPs to deliver BH4 to dysfunctional endothelial cells to increase nitric oxide bioavailability. BH4-loaded NPs could provide an innovative tool to restore redox balance in blood vessels and modulate eNOS-mediated vascular function to reverse or retard vascular disease in diabetes.

Quality by design (QbD) approach-based development of optimized nanocarrier to achieve quality target product profile (QTPP)-targeted lymphatic delivery

Background. Insulin, commonly used for diabetes treatment, needs better ways to improve its effectiveness and safety due to its challenges with poor permeability and stability. Various system has been developed for oral peptide delivery. The non-targeted system can prevent gastric and enzymatic degradation of peptides but cannot increase the bulk transport of peptides across the membrane. However, the non-selectivity is the limitation of the existing system. Numerous carbohydrate-binding receptors overexpressed on intestinal macrophage cells (M-cells) of gut-associated lymphoid tissue. It is the most desirable site for receptor-mediated endocytosis and lymphatic drug delivery of peptides. Objective. The prime objective of the study was to fabricate mannose ligand conjugated nanoparticles (MNPs) employing a quality-by-design approach to address permeability challenges after oral administration. Herein, the study’s secondary objective of this study is to identify the influencing factor for producing quality products. Considering this objective, the Lymphatic uptake of NPs was selected as a quality target product profile (QTPP), and a systematic study was conducted to identify the critical formulation attributes (CFAs) and critical process parameters (CPP) influencing critical quality attributes (CQAs). Mannosylated Chitosan concentrations (MCs) and TPP concentrations were identified as CFAs, and stirring speed was identified as CPP. Methods. MNPs were prepared by the inotropic gelation method and filled into the enteric-coated capsule to protect from acidic environments. The effect of CFAs and CPP on responses like particle size (X) and entrapment (Y) was observed by Box-Behnken design (BBD). ANOVA statistically evaluated the result to confirm a significant level (p < 0.05). The optimal conditions of NPs were obtained by constructing an overlay plot and determining the desirability value. HPLC and zeta-seizer analysis characterized the lyophilized NPs. Cell-line studies were performed to confirm the safety and M-cell targeting of NPs to enhance Insulin oral bioavailability. Results. The morphology of NPs was revealed by SEM. The developed NPs showed a nearly oval shape with the average size, surface potential, and % drug entrapment were 245.52 ± 3.37 nm, 22.12 ± 2.13 mV, and 76.15 ± 1.3%, respectively. MTT assay result exhibited that MNPs safe and Confocal imaging inference that NPs selectively uptake by the M-cell. Conclusion. BBD experimental design enables the effective formulation of optimized NPs. The statistical analysis estimated a clear assessment of the significance of the process and formulation variable. Cell line study confirms that NPs are safe and effectively uptake by the cell.

Lymphatic Uptake of a Highly Lipophilic Protease Inhibitor Prodrug from a Lipid-Based Formulation is Limited by Instability in the Intestine

Dabigatran etexilate (DABE) is a lipophilic double alkyl ester prodrug of dabigatran (DAB) which is a serine protease inhibitor used clinically as an anticoagulant. Recently, translocation of serine protease enzymes, including trypsin, from the gut into the mesenteric lymph and then blood has been associated with organ failure in acute and critical illnesses (ACIs). Delivery of DABE into mesenteric lymph may thus be an effective strategy to prevent organ failure in ACIs. Most drugs access the mesenteric lymph in low quantities following oral administration, as they are rapidly transported away from the intestine via the blood. Here, we examine the potential to deliver DABE into the mesenteric lymph by promoting association with lymph lipid transport pathways via co-administration with a lipid-based formulation (LBF). A series of self-emulsifying LBFs were designed and tested in vitro for their potential to form stable DABE loaded emulsions and keep DABE solubilised and stable over time in simulated gastrointestinal conditions. The LBFs were found to form fine emulsions with a droplet size of 214 ± 30 nm and DABE was stable in the formulation. The stability of DABE in vitro in simulated intestinal conditions, plasma and lymph samples was also evaluated to ensure stability in collected samples and to evaluate whether the prodrug is likely to release active DAB. Ultimately, a highly uniform and stable self-emulsifying Type III A LBF of DABE was chosen for progression into in vivo studies in male Sprague Dawley rats to confirm the lymphatic uptake and plasma pharmacokinetics. Both in vitro and in vivo in plasma and lymph, DABE was rapidly converted to an intermediate and DAB. The main species present in vivo in both plasma and lymph was DAB and mass transport of DABE and DAB in lymph was minimal (∼0.5 % of dose). Importantly, the concentration of DABE in lymph was substantially (20–176 fold) higher than in plasma, supporting that if the prodrug were stable and did not convert to DAB in the intestine, it would be lymphatically transported. Future studies will therefore focus on optimizing the design of the prodrug and formulation to improve stability during absorption and further promote lymphatic uptake.

Impact of conjugation to different lipids on the lymphatic uptake and biodistribution of brush PEG polymers

Delivery to peripheral lymphatics can be achieved following interstitial administration of nano-sized delivery systems (nanoparticles, liposomes, dendrimers etc) or molecules that hitchhike on endogenous nano-sized carriers (such as albumin). The published work concerning the hitchhiking approach has mostly focussed on the lymphatic uptake of vaccines conjugated directly to albumin binding moieties (ABMs such as lipids, Evans blue dye derivatives or peptides) and their subsequent trafficking into draining lymph nodes. The mechanisms underpinning access and transport of these constructs into lymph fluid, including potential interaction with other endogenous nanocarriers such as lipoproteins, have largely been ignored. Recently, we described a series of brush polyethylene glycol (PEG) polymers containing end terminal short-chain or medium-chain hydrocarbon tails (1C2 or 1C12, respectively), cholesterol moiety (Cho), or medium-chain or long-chain diacylglycerols (2C12 or 2C18, respectively). We evaluated the association of these materials with albumin and lipoprotein in rat plasma, and their intravenous (IV) and subcutaneous (SC) pharmacokinetic profiles. Here we fully detail the association of this suite of polymers with albumin and lipoproteins in rat lymph, which is expected to facilitate lymph transport of the materials from the SC injection site. Additionally, we characterise the thoracic lymph uptake, tissue and lymph node biodistribution of the lipidated brush PEG polymers following SC administration to thoracic lymph cannulated rats. All polymers had moderate lymphatic uptake in rats following SC dosing with the lymph uptake higher for 1C2-PEG, 2C12-PEG and 2C18-PEG (5.8%, 5.9% and 6.7% dose in lymph, respectively) compared with 1C12-PEG and Cho-PEG (both 1.5% dose in lymph). The enhanced lymph uptake of 1C2-PEG, 2C12-PEG and 2C18-PEG appeared related to their association profile with different lipoproteins. The five polymers displayed different biodistribution patterns in major organs and tissues in mice. All polymers reached immune cells deep within the inguinal lymph nodes of mice following SC dosing. The ability to access these immune cells suggests the potential of the polymers as platforms for the delivery of vaccines and immunotherapies. Future studies will focus on evaluating the lymphatic targeting and therapeutic potential of drug or vaccine-loaded polymers in pre-clinical disease models.

Enhancing lymphatic uptake of Darunavir Ethanolate through TPGS-enriched lipid nanocarriers for oral delivery

Darunavir ethanolate (DRVE) is a promising molecule against wild-type protease inhibitors in human immunodeficiency virus (HIV) infection. It has a 37% oral bioavailability. In this study, the d-alpha-Tocopheryl Polyethylene Glycol 1000 Succinate (TPGS)-decorated DRVE-loaded lipid nanocarriers (DRVE-TPGS-LNCs) were optimized via central composite rotatable design using a modified solvent emulsification method. Various characteristic features of DRVE-TPGS-LNCs, such as globule size, polydispersity index, zeta potential, % entrapment efficiency, and % drug loading, were determined and found to be 116.5 ± 2.52 nm, 0.269 ± 0.0221, −10.8 ± 0.265 mV, 94.31% ± 10.75%, and 8.79% ± 0.937%, respectively. The spherical shape was evaluated by cryo-transmission electron microscopy. In-vitro study demonstrated % cumulative drug release of 81.70% ± 7.35% at pH 1.2 and 73.03% ± 7.17% at pH 6.8 after 12 h of drug release study. Moreover, the intestinal permeation and confocal microscope studies revealed approximately two-fold increased permeation in optimized nanoformulation across the gut sac compared to a drug suspension, and the inhibition of p-glycoprotein efflux was also confirmed by obtaining a minimum efflux ratio (0.253) of the optimized formulation compared to a drug suspension. The pharmacokinetic study demonstrated that the relative bioavailability of TPGS-DRVE-LNCs and drug suspension were found to be 19.85 ± 1.75 and 8.72 ± 0.753 μg.h/mL, respectively, which is approximately 2.25-fold more than the drug suspension which means approximately threefold increase in oral bioavailability compared to the drug suspension. The increased bioavailability in optimized DRVE-TPGS-LNCs was due to improved lymphatic uptake and p-glycoprotein efflux inhibition. Thus, the improved bioavailability of DRVE can meet the need to reduce the high dose of antiretroviral drugs to minimize the peripheral adverse reactions associated with the dose-related burden.

Enhanced meningeal lymphatic drainage ameliorates lipopolysaccharide-induced brain injury in aged mice

BackgroundSepsis-associated encephalopathy (SAE) is an acute cerebral dysfunction caused by sepsis. Neuroinflammation induced by sepsis is considered a potential mechanism of SAE; however, very little is known about the role of the meningeal lymphatic system in SAE.MethodsSepsis was established in male C57BL/6J mice by intraperitoneal injection of 5 mg/kg lipopolysaccharide, and the function of meningeal lymphatic drainage was assessed. Adeno-associated virus 1-vascular endothelial growth factor C (AAV1-VEGF-C) was injected into the cisterna magna to induce meningeal lymphangiogenesis. Ligation of deep cervical lymph nodes (dCLNs) was performed to induce pre-existing meningeal lymphatic dysfunction. Cognitive function was evaluated by a fear conditioning test, and inflammatory factors were detected by enzyme-linked immunosorbent assay.ResultsThe aged mice with SAE showed a significant decrease in the drainage of OVA-647 into the dCLNs and the coverage of the Lyve-1 in the meningeal lymphatic, indicating that sepsis impaired meningeal lymphatic drainage and morphology. The meningeal lymphatic function of aged mice was more vulnerable to sepsis in comparison to young mice. Sepsis also decreased the protein levels of caspase-3 and PSD95, which was accompanied by reductions in the activity of hippocampal neurons. Microglia were significantly activated in the hippocampus of SAE mice, which was accompanied by an increase in neuroinflammation, as indicated by increases in interleukin-1 beta, interleukin-6 and Iba1 expression. Cognitive function was impaired in aged mice with SAE. However, the injection of AAV1-VEGF-C significantly increased coverage in the lymphatic system and tracer dye uptake in dCLNs, suggesting that AAV1-VEGF-C promotes meningeal lymphangiogenesis and drainage. Furthermore, AAV1-VEGF-C reduced microglial activation and neuroinflammation and improved cognitive dysfunction. Improvement of meningeal lymphatics also reduced sepsis-induced expression of disease-associated genes in aged mice. Pre-existing lymphatic dysfunction by ligating bilateral dCLNs aggravated sepsis-induced neuroinflammation and cognitive impairment.ConclusionThe meningeal lymphatic drainage is damaged in sepsis, and pre-existing defects in this drainage system exacerbate SAE-induced neuroinflammation and cognitive dysfunction. Promoting meningeal lymphatic drainage improves SAE. Manipulation of meningeal lymphangiogenesis could be a new strategy for the treatment of SAE.

Hydroxymethylnitrofurazone lymphatic uptake with nanostructured lipid carrier after oral administration in rats.

Background: Leishmaniasis, caused by the protozoan Leishmania sp., infects phagocyte cells present in lymphatic organs. This study demonstrates the influence of nanostructured lipid carrier-loaded hydroxymethylnitrofurazone (NLC-NFOH) on lymphatic uptake using a chylomicron-blocking flow model in rats. Method: Lymphatic uptake of NFOH was assessed 1h after oral administration of dimethyl sulfoxide with NFOH or NLC-NFOH with and without cycloheximide pretreatment. Result: Dimethyl sulfoxide with NFOH and NLC-NFOH showed NFOH serum concentrations of 0.0316 and 0.0291μg/ml, respectively. After chylomicron blocking, NFOH was not detected. Conclusion: Despite log P below 5, NFOH was successfully taken up by the lymphatic system. Long-chain fatty acids and particle size might be main factors in these findings. NLC-NFOH is a promising and convenient platform for treating leishmaniasis via oral administration.

Intradermal delivery of the antiretroviral drugs cabotegravir and rilpivirine by dissolving microarray patches: Investigation of lymphatic uptake

The lymphatic system possesses the main viral replication sites in the body following viral infection. Unfortunately, current antiretroviral agents penetrate the lymph nodes insufficiently when administered orally and, therefore, cannot access the lymphatic system sufficiently to interrupt this viral replication. For this reason, novel drug delivery systems aimed at enhancing the lymphatic uptake of antiretroviral drugs are highly desirable. Dissolving polymeric microarray patches (MAPs) may help to target the lymph intradermally. MAPs are intradermal drug delivery systems used to deliver many types of compounds. The present work describes a novel work investigating the lymphatic uptake of two anti-HIV drugs: cabotegravir (CAB) and rilpivirine (RPV) when delivered intradermally using dissolving MAPs containing nanocrystals of both drugs. Maps were formulated using NCs obtained by solvent-free milling technique. The polymers used to prepare the NCs of both drugs were PVA 10 Kda and PVP 58 Kda. Both NCs were submitted to the lyophilization process and reconstituted with deionized water to form the first layer of drug casting. Backing layers were developed for short application times and effective skin deposition. In vivo biodistribution profiles of RPV and CAB after MAP skin application were investigated and compared with the commercial intramuscular injection using rats. After a single application of RPV MAPs, a higher concentration of RPV was delivered to the axillary lymph nodes (AL) (Cmax 2466 ng/g – Tmax 3 days) when compared with RPV IM injection (18 ng/g - Tmax 1 day), while CAB MAPs delivered slightly lower amounts of drug to the AL (5808 ng/g in 3 days) when compared with CAB IM injection (9225 ng/g in 10 days). However, CAB MAPs delivered 7726 ng/g (Tmax 7 days) to the external lumbar lymph nodes, which was statistically equivalent to IM delivery (Cmax 8282 ng/g - Tmax 7 days). This work provides strong evidence that MAPs were able to enhance the delivery of CAB and RPV to the lymphatic system compared to the IM delivery route.

Fabrication of TPGS decorated Etravirine loaded lipidic nanocarriers as a neoteric oral bioavailability enhancer for lymphatic targeting

Etravirine (ERVN) is a potential NNRTI (non-nucleoside reverse transcriptase inhibitor) in treating HIV infection. It possesses extremely low oral bioavailability. The present research aims to optimize the formulation and characterization of TPGS-enriched ERVN-loaded lipid-based nanocarriers (NLCs) for HIV-infected patients. The formulation, ERVN–TPGS–NLCs, was optimized by central composite rotational design using a modified-solvent emulsification process. Various characterization parameters of NLCs were evaluated, including globule size of 121.56 ± 2.174 nm, PDI of 0.172 ± 0.042, the zeta potential of − 7.32 ± 0.021 mV, %EE of 94.42 ± 8.65% of ERVN and %DL was 8.94 ± 0.759% of ERVN and spherical shape was revealed by TEM. PXRD was also performed to identify the crystallinity of the sample. In-vitro drug release showed % a cumulative drug release of 83.72 ± 8.35% at pH 1.2 and 90.61 ± 9.11% at pH 6.8, respectively, whereas the % cumulative drug release from drug suspension (ERVN-S) was found to be 21.13 ± 2.01% at pH 1.2 and 24.84 ± 2.51 at pH 6.8 at the end of 48 h. Further, the intestinal permeation study and confocal microscope showed approximately three-fold and two-fold increased permeation in ERVN–TPGS–NLCs and ERVN-NLCs across the gut sac compared to ERVN-S. Hemolysis compatibility and lipolysis studies were performed to predict the in-vivo fate of the formulation. The pharmacokinetic study revealed a 3.13-fold increment in the relative bioavailability, which agrees with the ex-vivo studies, and lymphatic uptake was validated by using cycloheximide along with designed formulation, which showed the impact of lymphatic uptake in AUC. This study ensures that ERVN–TPGS–NLCs take lymphatic uptake to minimize the first-pass metabolism followed by improved oral bioavailability of ERVN. Thus, the enhanced bioavailability of ERVN can reduce the high dose of ERVN to minimize the adverse effects related to dose-related burden.Graphical abstract

Advancements in Nutraceutical Delivery: Integrating Nanotechnology and Microencapsulation for Enhanced Efficacy and Bioavailability

Abstract Nutraceuticals, derived from various foods, have gained significance for promoting health and managing diseases. Despite their nutritional value, challenges such as low solubility, poor diffusion, gastrointestinal instability, and limited bioavailability impede their effectiveness as preventive agents. Nanotechnology-driven drug delivery systems, including liposomes, nanospheres, nanoemulsions, micelles, and nanocrystals, offer innovative solutions to enhance efficacy and oral bioavailability. These advanced formulations not only augment the physicochemical properties and therapeutic efficacy of nutraceuticals but also enable targeted delivery. A diverse range of nanocarriers, encompassing liposomes to inorganic nanoparticles, addresses specific challenges in nutraceutical formulations, exhibiting unique properties such as heightened stability, palatability, and lymphatic uptake for increased bioavailability. Lipid nanocarriers facilitate the permeation of neuroprotective nutraceuticals through the blood–brain barrier, while liposomal delivery systems shield bioactives from oxidation and light, accommodating both hydrophilic and lipophilic compounds. In addition, polymeric nanocarriers, exemplified by micelles, outperform lipidic counterparts, ensuring controlled release. Natural sources contribute to the development of polymeric nanoparticles, offering controlled delivery with reduced toxicity. Polysaccharides and proteins diversify delivery platforms, encompassing the loading of nutraceuticals and functional nutrients. Nanotechnology emerges as a pivotal player in advancing the solubility, bioavailability, and stability of bioactives, with ongoing research focused on refining formulations, like curcumin, for effective cancer and inflammation management. While these advancements hold promise, careful consideration of challenges, including toxicity and cost, is imperative to fully unlock the potential of nanotechnology in nutraceutical delivery, ensuring both safety and cost-effectiveness. The significance of microencapsulation and nanotechnology in the nutraceutical delivery system is thoroughly explored in this comprehensive review.