Pro-inflammatory macrophage polarization enhances the anti-cancer efficacy of self-assembled galactomannan nanoparticles entrapped with hydrazinocurcumin Abstract Galactomannan (GM), a natural polymer, is recognized to specifically target macrophage mannose receptors (CD206). Interestingly, some reports indicate that GM has an ability to induce pro-inflammatory (M1-like, tumericidal) polarization in macrophages, suggesting its potential use as an anti-cancer agent. Hydrazinocurcumin (HC), a pyrazole derivative of curcumin, is reported to possess increased anti-cancer efficacy over curcumin. Moreover, HC-encapsulated nanoparticles (NPs) have been reported to re-polarize tumor-associated macrophages (TAMs) from anti-inflammatory (M2-like, tumor-promoting) to pro-inflammatory phenotype. To club the therapeutic properties of both GM and HC, we synthesized self-assembled amphiphilic PEGylated GM NPs loaded with HC (PSGM-HCNPs) and evaluated their potential to re-polarize TAMs towards M1-like phenotype. PSGM-HCNPs re-polarized IL-4 polarized RAW 264.7 cells via a phenotypic switch from M2- to M1-like by elevating ROS level, decreasing CD206 and arginase-1 expressions and increasing pro-inflammatory cytokines’ secretion. Conditioned medium (CM) taken from re-polarized RAW 264.7 cells containing residual PSGM-HCNPs elevated ROS, arrested cell cycle, and induced apoptosis in 4T1, breast cancer cells, and Ehrlich’s ascites carcinoma (EAC) cells. Decreased levels of MMP-2, MMP-9, and Bcl-2 with increased levels of Bax in both 4T1 and EAC cells indicated anti-metastatic and apoptosis-inducing potential of the CM. Treatment of PSGM-HCNPs in EAC-bearing mice reduced tumor burden, increased their survival time, decreased CD206+F4/80+ cells, and increased TNF-α+F4/80+ cells signifying decrease in M2- and increase in M1-like skewness among ascitic TAMs.

Delivery of therapeutic miRNA using polymer-based formulation Abstract MicroRNAs (miRNAs) are short non-coding RNAs that play important roles in many cellular processes such as development, proliferation, differentiation, and apoptosis. For this reason, miRNAs have been proposed and investigated as biomarkers and therapeutics for various diseases such as cancer, diabetes, and cardiovascular disease. However, delivery of miRNAs and their antagomirs to target sites remains challenging because of poor cellular uptake and degradation by nucleases. Various delivery systems have been investigated for enhanced delivery of miRNAs to cells, organs, and tissues of interest, thereby enabling evaluation of their biological functions and clinical trials. In particular, non-viral, polymer-based carriers have shown advantages such as versatility of structural modifications and protection of unstable miRNA. Herein, we review properties and applications of poly (lactic-co-glycolic acid), chitosan, polyethyleneimine, and polyamidoamine dendrimers as carriers for effective delivery systems of miRNA mimic or anti-miRNAs that directly target essential miRNAs and/or their target genes. A number of miRNAs in clinical trials appear to use chemically modified miRNAs without any particular delivery system except one study with liposomal miRNA. With more accumulation of positive research results on polymeric delivery of miRNA in vitro and in vivo, we expect that polymeric delivery system will accelerate advancement of miRNA therapeutics to clinical study in the near future.

Tumor growth inhibition by mSTEAP peptide nanovaccine inducing augmented CD8 + T cell immune responses Abstract Poly(lactic-co-glycolic) acid (PLGA) has been successfully used in drug delivery and biomaterial applications, but very little attention has been directed towards the potential in vivo effects of peptide-loaded PLGA nanoparticles (NPs), specifically the potency of intravenous (IV) STEAP peptide-loaded PLGA-NP (nanovaccine) dosing and whether STEAP-specific CD8+ T cells directly play a key role in tumor inhibition. To address these concerns, syngeneic prostate cancer mouse models were established and treated with either mSTEAP peptide emulsified in incomplete Freund’s adjuvant (IFA) via subcutaneous (SC) injection or mSTEAP peptide nanovaccine containing the same amount of peptide via IV or SC injection. Meanwhile, mice were treated with either CD8b mAb followed by nanovaccine treatment, free mSTEAP peptide, or empty PLGA-NPs. Immune responses in these mice were examined using cytotoxicity assays at 14 days after treatment. Tumor size and survival in various treatment groups were measured and monitored. The results demonstrated that mSTEAP peptide nanovaccine resulted in tumor inhibition by eliciting a significantly stronger CD8+ T cell immune response when compared with the controls. Moreover, the survival periods of mice treated with mSTEAP nanovaccine were significantly longer than those of mice treated with mSTEAP peptide emulsified in IFA or the treatment controls. Additionally, it was observed that the peptide nanovaccine was mainly distributed in the mouse liver and lungs after IV injection. These findings suggest that the peptide nanovaccine is a promising immunotherapeutic approach and offers a new opportunity for prostate cancer therapies.

Macrophage polarization in wound healing: role of aloe vera/chitosan nanohydrogel Abstract The balance between M1 and M2 macrophages plays an important role in wound healing. Interestingly, this immune response can be modulated by natural biomaterials such as chitosan nanohydrogel (Ch) and aloe vera (AV). Therefore, we aimed to improve wound recovery response by exploiting the potential healing properties of Ch and AV. Wounds were created in rats and were treated daily with either saline (control), AV, Ch, or different ratios of AV (volume):Ch (weight) (1:1), (2:1), and (3:1). M1 (iNOS, TNF-α) and M2 (CD163, TGF-β) responses were analyzed at days 3, 7, 14, 21, and 28. Wound healing increased within the third and seventh days in AV-Ch (3:1) (P < 0.001 and P < 0.002, respectively). In the treated groups, immunohistochemistry of iNOS expression decreased on the third day (P < 0.0001) while CD163 increased (P < 0.0001) on the 3rd, 7th, and 14th days. The gene expression of TGF-β decreased on the third day in AV group (P < 0.03) and on the 21st and 28th days in Ch-treated group (P < 0.00). TNF-α expression decreased in AV, Ch, and AV-Ch (3:1 v/w) on the 14th and 28th days (P < 0.00). TGF-β and TNF-α proteins decreased on the 28th day compared to the control and AV-Ch (3:1 v/w), respectively. AV-Ch (1 and 3:1 v/w) and Ch resulted in optimum wound repair by decreasing M1 after 3 days and increasing M2 after 14. Thus, Ch nanohydrogel, especially in combination with 1:1 and 1:3 ratio to AV, could be a proper candidate for modulating macrophages in response to wound healing.

Recent advances in cyclosporine drug delivery: challenges and opportunities Abstract Cyclosporine has been established as a gold standard for its immunosuppressant action. Apart from this, the molecule is boon in treating broad spectrum of diseases like rheumatoid arthritis, psoriasis, and dry eye syndrome. The broad spectrum of cyclosporine demands efficient delivery systems by several routes. Neoral® and Sandimmune® are currently available formulations for oral route, whereas Restasis® is used for ocular delivery of cyclosporine. The available formulations serve the purpose only to a limited extent due to constraints like high molecular weight, low solubility, low permeability, bitter taste, and narrow therapeutic index of cyclosporine. Therefore, several novel formulations like microemulsion, self-emulsifying systems, nanoparticles, and microspheres were developed to overcome these constraints, exploring different routes like oral, ocular, and topical for cyclosporine. Additionally, iontophoresis and ultrasound-mediated delivery has also been studied to improve its poor permeability in topical delivery, whereas biodegradable implants were reported to increase the retention time in cornea and prolonged the release of cyclosporine by ocular route. Although these recent advances in cyclosporine delivery look promising, its clinical translation require in depth studies to deliver safe, efficacious, and stable formulation of cyclosporine. This review focuses on challenges of cyclosporine delivery and the recent advancements for overcoming the constraints.

Anti-pollution cosmetic-based one-step formation of w/o/w multiple emulsion containing D-biotin for skin protection: fabrication and in vitro and in vivo evaluation Abstract Continuous contact of air pollutants on human skin has produced early ageing and led to roughness, dryness, poor elasticity, increased wrinkling and irregular pigmentation of the skin. The present study was carried out to fabricate an anti-pollution cosmetic-based w/o/w multiple emulsion containing D-biotin, prepared by a one-step formation as protection for the skin against the effects of air pollutants and further used for in vitro and in vivo evaluation. A similar multiple emulsion without D-biotin was also prepared in the same way. Each of the tested multiple emulsions (CB2 and CF2) was applied to the cheeks of 15 human volunteers for a testing period of 90 days. Both emulsions were assessed for skin melanin, erythema, hydration and elasticity values. The droplet sizes of CB2 and CF2 stored in the dark were 10.92 ± 0.23 and 15.4 ± 0.12 μm, respectively. The size distributions of CB2 and CF2 ranged from 4.55 ± 0.1 to 26.056 ± 0.34 μm and from 1.97.16 ± 1.2 to 45.13 ± 2.17 μm, respectively. The rheological parameters showed non-Newtonian, pseudo-plastic and shear thinning behaviour, while pH remained within an acceptable range. No considerable physical changes were observed. The skin irritation testing indicated that CB2 and CF2 were safe after application and did not cause any skin irritation. The skin melanin, erythema, moisture and elasticity values of both the right and left cheeks of the volunteers were measured at baseline visits: 15, 30, 45, 60, 75 and 90 days of time intervals. While CB2 showed insignificant effects, therefore, it was demonstrated that CF2 decreased skin erythema content and increased skin elasticity and hydration significantly but had an insignificant effect on skin melanin content with respect to time. Good sensory attributes were also achieved. Therefore, CF2 is a promising new approach for protection of the skin from the deleterious effects of air pollutants.

Chlorpheniramine maleate containing chitosan-based nanoparticle-loaded thermosensitive in situ gel for management in allergic rhinitis Abstract The aim of the present study was to fabricate a thermosensitive gel containing chlorpheniramine maleate (CPM)–loaded nanoparticles following intranasal administration for effective treatment of allergic rhinitis. Chitosan-based nanoparticles were prepared by a precipitation method followed by the addition of developed NPs within the poloxamer 407– and carbopol 934P–based mucoadhesive thermoreversible gel. Developed formulations were evaluated for particle size, PDI, % entrapment efficiency, and % cumulative drug permeation. NP3 formulation was found to be optimized on the basis of minimum particle size (143.9 nm), maximum entrapment efficiency (80.10 ± 0.414%), and highest drug permeation (90.92 ± 0.531%). The optimized formulation NP3 was then formulated into thermoreversible in situ gel. This intensifies the contact between the nasal mucosa and the drug and increases and facilitates the drug absorption which results in increased bioavailability. G4 formulation was selected as the optimized formulation on the basis of gelation ability and mucoadhesive strength. Histology was carried out to examine the damage caused by the optimized G4 formulation. Results revealed no visual signs of tissue damage thus indicated safe nasal delivery of nanoparticulate in situ gel formulation G4. Thus, intranasal CPM NP–loaded in situ gel was found to be a promising formulation for the management of allergic rhinitis.

Novel bergamot oil nanospanlastics combined with PUVB therapy as a clinically translatable approach for vitiligo treatment Abstract The impact of nanomedicine has grown in the current decade; however, only very few clinical translational attempts have been realized. Therefore in the present study, we hypothesized that bergamot oil, a psoralen-containing oil, would produce an optimized melanogenic effect in the clinical treatment of vitiligo when loaded within an elastic nanocarrier (spanlastics) and combined with PUVB for activation of psoralens. Spanlastics were prepared and characterized for particle size, physical stability, in vitro release, thermal behavior, deformability, morphology, and in vitro photostability. The efficacy of the selected formula was tested histopathologically on rat skin and clinically translated in patients suffering from vitiligo. Results revealed that the spanlastics were of reasonable nanosize, deformable, and provided sustained release of bergamot oil. The incorporation of bergamot oil within spanlastics improved its photostability and its photodynamic activity. Spanlastics exhibited promising clinical results in terms of extent and onset of repigmentation in vitiligo patients. Therefore, it can be concluded that spanlastics can be introduced as a promising nanotreatment modality for vitiligo.

The maximum possible amount of drug in rapidly separating microneedles Abstract There is an increasing concern on the drug loading capacity of microneedles (MNs) to meet higher drug dosage requirement. The present study describes the fabrication of modified rapidly separating polyvinyl alcohol (PVA)-based MNs (RS-P-MNs) with high drug loading using a mechanical agitation process. The drugs encapsulated within the PVA polymer gel by mechanical agitation served as an encapsulating agent for drugs that provide a high drug loading capacity and also release of drugs in a controlled manner. The various parameters such as microscopic analysis, atomic force microscopy (AFM), drug loading, drug delivery efficiency, mechanical test, skin penetration ability, and in vitro and in vivo analyses indicate the great potential of the RS-P-MNs. The maximum drug loading capacity of RS-P-MNs was measured to be approximately 900 ng per microneedle, which was almost a hundred times than the traditional drug encapsulating mode. The in vitro and in vivo results suggested that the controlled release of drugs is due to the encapsulating mode (mechanical agitation) of drugs. The prepared RS-P-MNs with high drug loading in this study provided a gentle and controlled release of drugs instead of the robust release of drugs from traditional MNs. Graphical abstract

Accelerated and scarless wound repair by a multicomponent hydrogel through simultaneous activation of multiple pathways Abstract Scarless healing of injury remains a clinical challenge because of its complicated and overlapping phases of inflammation, clearing, and regeneration. Curcumin has been already established as a potential wound healing agent for normal and diabetic-impaired wounds. Herein, the question has been addressed whether a well-known antioxidant cerium oxide nanoparticle (CNP) can potentiate the activity of curcumin to promote a cellular program for scarless healing. In this study, we have developed a biocompatible poly (acrylamide) hydrogel (PAGE)-based dressing material comprising of CNP and curcumin (ACC) and tested its wound healing activity in an animal model of acute wound. Characterization of the CNP- and curcumin-entrapped hydrogel dressing (ACC) demonstrated high loading efficiency and sustained release of curcumin. In a full-thickness acute wound healing model of rat, a single application of ACC dressing demonstrated higher wound healing efficacy (78%) and negligible scarring compared to dressings containing only curcumin or CNP in 7 days. Enhanced cell proliferation, higher collagen content, advanced wound maturity, re-epithelialization, and granulation tissue formation were observed using the combination of curcumin and CNP (ACC). Study of cellular mechanisms identified MCP-1 and TGF-β as the key drivers of differential and accelerated healing observed in the ACC group. These, coupled with the upregulation of growth-related signaling pathways (HER2/ErbB2, TGF-β-Smad2/3, MAPK/ERK, AKT, and VEGF), promoted almost scarless healing in animals treated with ACC. The optimized combination of curcumin and CNP used in our study shows distinct advantage and can be a better agent for complete wound healing.