Advanced nanoscale delivery systems for mRNA-based vaccines

The effectiveness of messenger RNA (mRNA) vaccines, especially those designed for COVID-19, relies heavily on sophisticated delivery systems that ensure efficient delivery of mRNA to target cells. A variety of nanoscale vaccine delivery systems (VDSs) have been explored for this purpose, including lipid nanoparticles (LNPs), liposomes, and polymeric nanoparticles made from biocompatible polymers such as poly(lactic-co-glycolic acid), as well as viral vectors and lipid-polymer hybrid complexes. Among these, LNPs are particularly notable for their efficiency in encapsulating and protecting mRNA. These nanoscale VDSs can be engineered to enhance stability and facilitate uptake by cells. The choice of delivery system depends on factors like the specific mRNA vaccine, target cell types, stability requirements, and desired immune response. In this review, we shed light on recent advances in delivery mechanisms for self-amplifying RNA (saRNA) vaccines, emphasizing groundbreaking studies on nanoscale delivery systems aimed at improving the efficacy and safety of mRNA/saRNA vaccines.

Astaxanthin-loaded alginate-chitosan gel beads activate Nrf2 and pro-apoptotic signalling pathways against oxidative stress

Oxidative stress (OS) plays a crucial role in disease development. Astaxanthin (ATX), a valuable natural compound, may reduce OS and serve as a treatment for diseases like neurodegenerative disorders and cancer. Nuclear factor-erythroid 2-related factor 2 (Nrf2) regulates antioxidant enzymes and OS management. We evaluated ATX's antioxidant activity via Alg-CS/ATX gel beads in vitro. ATX-encapsulated alginate-chitosan (Alg-CS/ATX) gel beads were synthesized and structurally/morphologically characterized by SEM, FT-IR, and XRD. Their biological effects were examined in human umbilical vein endothelial cells (HUVECs) treated with H2O2 through MTT assay, Annexin V/PI, cell cycle studies, and western blotting. Alg-CS effectively carried ATX, with high capacity and reduced pore size. Alg-CS/ATX displayed an 84% encapsulation efficiency, maintaining stability for 30 days. In vitro studies showed a 1.4-fold faster release at pH 5.4 than at neutral pH, improving ATX's therapeutic potential. HUVECs treated with Alg-CS/ATX showed enhanced viability via increased Nrf2 expression. Alg-CS gel beads exhibit significant potential as a biocompatible vehicle for delivering ATX to combat OS with considerable opportunity for clinical applications.

Atherosclerosis preventive effects of marrubiin against (TNF-α)-induced oxidative stress and apoptosis

Introduction

Atherosclerosis is a complicated cascade of inflammatory processes, oxidative stress, and apoptosis, making it the most prevalent cardiovascular disease. The onset and progression of cardiovascular diseases are greatly influenced by oxidative stress. Targeting oxidative stress is an effective strategy for treating such diseases. Marrubiin is a bioactive furan labdane diterpenoid acts as a strong antioxidant to protect against oxidative damage. This study aimed to investigate the protective effects of marrubiin against oxidative stress and apoptosis in a cellular model of the vascular system.

Methods

Human umbilical vein endothelial cells were treated with varying concentration of marrubiin and its IC50 value was determined. The antioxidant potential of marrubiin was assessed by measuring the intracellular level of glutathione (GSH) using a colorimetric technique. Since apoptosis plays a significant role in the plaque rupture, the study also evaluated the protective effects of marrubiin on the expression of key genes involved in apoptotic pathways.

Results

Cells treated with marrubiin showed increased GSH levels compared to cell therapy control cells, indicating marrubiin's ability to counteract the effects of TNF-α's on GSH levels. Furthermore real-time PCR analysis demonstrated that marrubiin upregulated Bcl-xl while downregulating caspase3 and Nox4 in treated cells. These findings suggest that marrubiin protects against apoptosis and oxidative stress.

Conclusion

Based on our findings, marrubiin is recommended as a preventive/therapeutic treatment for diseases caused by elevated intracellular reactive oxygen species levels in cardiovascular diseases.

SARS-CoV-2 vaccine-triggered autoimmunity: Molecular mimicry and/or bystander activation of the immune system

Induced autoimmunity or autoinflammatory-like conditions as a rare vaccine-related adverse event have been reported following COVID-19 vaccination. Such inadvertent adverse reactions have raised somewhat concerns about the long-term safety of the developed vaccines. Such multifactorial phenomena may be related to the cross-reactivity between the viral-specific antigens with the host self-proteins through molecular mimicry mechanism and/or nonspecific bystander activation of the non-target antigen-independent immunity by the entities of the vaccine products. However, due to the low incidence of the reported/identified individuals and insufficient evidence, autoimmunity following the COVID-19 vaccination has not been approved. Thereby, it seems that further designated studies might warrant post-monitoring of the inevitable adverse immunologic reactions in the vaccinated individuals, especially among hypersensitive cases, to address possible immunological mechanisms induced by the viral vaccines, incorporated adjuvants, and even vaccine delivery systems.

Advanced nanoscale drug delivery systems for bone cancer therapy

Bone tumors are relatively rare, which are complex cancers and mostly involve the long bones and pelvis. Bone cancer is mainly categorized into osteosarcoma (OS), chondrosarcoma, and Ewing sarcoma. Of these, OS is the most intimidating cancer of the bone tissue, which is mostly found in the log bones in young children and older adults. Conspicuously, the current chemotherapy modalities used for the treatment of OS often fail mainly due to (i) the non-specific detrimental effects on normal healthy cells/tissues, (ii) the possible emergence of drug resistance mechanisms by cancer cells, and (iii) difficulty in the efficient delivery of anticancer drugs to the target cells. To impose the maximal therapeutic impacts on cancerous cells, it is of paramount necessity to specifically deliver chemotherapeutic agents to the tumor site and target the diseased cells using advanced nanoscale multifunctional drug delivery systems (DDSs) developed using organic and inorganic nanosystems. In this review, we provide deep insights into the development of various DDSs applied in targeting and eradicating OS. We elaborate on different DDSs developed using biomaterials, including chitosan, collagen, poly(lactic acid), poly(lactic-co-glycolic acid), polycaprolactone, poly(ethylene glycol), polyvinyl alcohol, polyethyleneimine, quantum dots, polypeptide, lipid NPs, and exosomes. We also discuss DDSs established using inorganic nanoscale materials such as magnetic NPs, gold, zinc, titanium NPs, ceramic materials, silica, silver NPs, and platinum NPs. We further highlight anticancer drugs' role in bone cancer therapy and the biocompatibility of nanocarriers for OS treatment.

Fabrication of mesoporous silica nanoparticles for targeted delivery of sunitinib to ovarian cancer cells

INTRODUCTION

Mesoporous silica nanoparticles (MSNPs) are considered innovative multifunctional structures for targeted drug delivery owing to their outstanding physicochemical characteristics.

METHODS

MSNPs were fabricated using the sol-gel method, and polyethylene glycol-600 (PEG600) was used for MSNPs modification. Subsequently, sunitinib (SUN) was loaded into the MSNPs, MSNP-PEG and MSNP-PEG/SUN were grafted with mucin 16 (MUC16) aptamers. The nanosystems (NSs) were characterized using FT-IR, TEM, SEM, DLS, XRD, BJH, and BET. Furthermore, the biological impacts of MSNPs were evaluated on the ovarian cancer cells by MTT assay and flow cytometry analysis.

RESULTS

The results revealed that the MSNPs have a spherical shape with an average dimension, pore size, and surface area of 56.10 nm, 2.488 nm, and 148.08 m2g-1, respectively. The cell viability results showed higher toxicity of targeted MSNPs in MUC16 overexpressing OVCAR-3 cells as compared to the SK-OV-3 cells; that was further confirmed by the cellular uptake results. The cell cycle analysis exhibited that the induction of sub-G1 phase arrest mostly occurred in MSNP-PEG/SUN-MUC16 treated OVCAR-3 cells and MSNP-PEG/SUN treated SK-OV-3 cells. DAPI staining showed apoptosis induction upon exposure to targeted MSNP in MUC16 positive OVCAR-3 cells.

CONCLUSION

According to our results, the engineered NSs could be considered an effective multifunctional targeted drug delivery platform for the mucin 16 overexpressing cells.

Targeted Delivery of Sunitinib by MUC-1 Aptamer-Capped Magnetic Mesoporous Silica Nanoparticles

Magnetic mesoporous silica nanoparticles (MMSNPs) are being widely investigated as multifunctional novel drug delivery systems (DDSs) and play an important role in targeted therapy. Here, magnetic cores were synthesized using the thermal decomposition method. Further, to improve the biocompatibility and pharmacokinetic behavior, mesoporous silica was synthesized using the sol-gel process to coat the magnetic cores. Subsequently, sunitinib (SUN) was loaded into the MMSNPs, and the particles were armed with amine-modified mucin 1 (MUC-1) aptamers. The MMSNPs were characterized using FT-IR, TEM, SEM, electrophoresis gel, DLS, and EDX. MTT assay, flow cytometry analysis, ROS assessment, and mitochondrial membrane potential analysis evaluated the nanoparticles' biological impacts. The physicochemical analysis revealed that the engineered MMSNPs have a smooth surface and spherical shape with an average size of 97.6 nm. The biological in vitro analysis confirmed the highest impacts of the targeted MMSNPs in MUC-1 overexpressing cells (OVCAR-3) compared to the MUC-1 negative MDA-MB-231 cells. In conclusion, the synthesized MMSNP-SUN-MUC-1 nanosystem serves as a unique multifunctional targeted delivery system to combat the MUC-1 overexpressing ovarian cancer cells.

Injectable thermosensitive chitosan/gelatin hydrogel for dental pulp stem cells proliferation and differentiation

Introduction: Biocompatible and biodegradable scaffolds based on natural polymers such as gelatin and chitosan (CS) provide suitable microenvironments in dental tissue engineering. In the present study, we report on the synthesis of injectable thermosensitive hydrogel (PNIPAAm-g-CS copolymer/gelatin hybrid hydrogel) for osteogenic differentiation of human dental pulp stem cells (hDPSCs). Methods: The CS-g-PNIPAAm was synthesized using the reaction of carboxyl terminated PNIPAAm with CS, which was then mixed with various amounts of gelatin solution in the presence of genipin as a chemical crosslinker to gain a homogenous solution. The chemical composition and microstructures of the fabricated hydrogels were confirmed by FT-IR and SEM analysis, respectively. To evaluate the mechanical properties (e.g., storage and loss modulus of the gels), the rheological analysis was considered. Calcium deposition and ALP activity of DPSCs were carried out using alizarin red staining and ALP test. While the live/dead assay was performed to study its toxicity, the real-time PCR was conducted to investigate the osteogenic differentiation of hDPSCs cultured on prepared hydrogels. Results: The hydrogels with higher gelatin incorporation showed a slightly looser network compared to the other ones. The hydrogel with less gelatin indicates a rather higher value of G', indicating a higher elasticity due to more crosslinking reaction of amine groups of CS via a covalent bond with genipin. All the hydrogels contained viable cells with negligible dead cells, indicating the high biocompatibility of the prepared hydrogels for hDPSCs. The quantitative results of alizarin red staining displayed a significant rise in calcium deposition in hDPSCs cultured on prepared hydrogels after 21 days. Further, hDPSCs cultured on hydrogel with more gelatin displayed the most ALP activity. The expression of late osteogenic genes such as OCN and BMP-2 were respectively 6 and 4 times higher on the hydrogel with more gelatin than the control group after 21 days. Conclusion: The prepared PNIPAAm-g-CS copolymer/gelatin hybrid hydrogel presented great features (e.g., porous structure, suitable rheological behavior, and improved cell viability), and resulted in osteogenic differentiation necessary for dental tissue engineering.

Self-amplifying mRNA vaccines: Mode of action, design, development and optimization

The mRNA-based vaccines are quality-by-design (QbD) immunotherapies that provide safe, tunable, scalable, streamlined and potent treatment possibilities against different types of diseases. The self-amplifying mRNA (saRNA) vaccines, as a highly advantageous class of mRNA vaccines, are inspired by the intracellular self-multiplication nature of some positive-sense RNA viruses. Such vaccine platforms provide a relatively increased expression level of vaccine antigen(s) together with self-adjuvanticity properties. Lined with the QbD saRNA vaccines, essential optimizations improve the stability, safety, and immunogenicity of the vaccine constructs. Here, we elaborate on the concepts and mode-of-action of mRNA and saRNA vaccines, articulate the potential limitations or technical bottlenecks, and explain possible solutions or optimization methods in the process of their design and development.

Recombinant production and characterization of L-glutaminase (glsA) as a promiscuity therapeutic enzyme

Because of the therapeutical impacts of hydrolytic enzymes in different diseases, in particular malignancies, we aimed to produce a recombinant putative L-glutaminase (GLS A_SL-1) from a recently characterized halo-thermotolerant Bacillus sp. SL-1. For this purpose, the glsA gene was identified and efficiently overexpressed in the Origami™ B (DE3) strain. The yield of the purified GLS A_SL-1 was ~ 20 mg/L, indicating a significant expression of recombinant enzyme in the Origami. The enzyme activity assay revealed a significant hydrolytic effect of the recombinant GLS A_SL-1 on L-asparagine (Asn) (i.e., K_m 39.8 μM, k_cat 19.9 S^-1) with a minimal affinity for L-glutamine (Gln). The GLS A_SL-1 significantly suppressed the growth of leukemic Jurkat cells through apoptosis induction (47.5%) in the IC₅₀ dosage of the enzyme. The GLS A_SL-1 could also change the Bax/Bcl2 expression ratio, indicating its apoptotic effect on cancer cells. The in silico analysis was conducted to predict structural features related to the histidine-tag exposure in the N- or C-terminal of the recombinant GLS A_SL-1. In addition, molecular docking simulation for substrate specificity revealed a greater binding affinity of Asn to the enzyme binding-site residues than Gln, which was confirmed in experimental procedures as well. In conclusion, the current study introduced a recombinant GLS A_SL-1 with unique functional and structural features, highlighting its potential pharmaceutical and medical importance. GLS A_SL-1 represents the first annotated enzyme from Bacillus with prominent asparaginase activity, which can be considered for developing alternative enzymes in therapeutic applications. KEY POINTS: • Hydrolytic enzymes have critical applications in different types of human malignancies. • A recombinant L-glutaminase (GLS A_SL-1) was produced from halo-thermotolerant Bacillus sp. SL-1. • GLS A_SL-1 displayed a marked hydrolytic activity on L-asparagine compared to the L-glutamine. • GLS A_SL-1 with significant substrate promiscuity may be an alternative for developing novel pharmaceuticals.

Optogenetics: A new tool for cancer investigation and treatment

Despite the progress made in the diagnosis and treatment of cancer, it has remained the second cause of death in industrial countries. Cancer is a complex multifaceted disease with unique genomic and proteomic hallmarks. Optogenetics is a biological approach, in which the light-sensitive protein modules in combination with effector proteins that trigger reversibly fundamental cell functions without producing a long-term effect. The technology was first used to address some key issues in neurology. Later on, it was also used for other diseases such as cancer. In the case of cancer, there exist several signaling pathways with key proteins that are involved in the initiation and/or progression of cancer. Such aberrantly expressed proteins and the related signaling pathways need to be carefully investigated in terms of cancer diagnosis and treatment, which can be managed with optogenetic tools. Notably, optogenetics systems offer some advantages compared to the traditional methods, including spatial-temporal control of protein or gene expression, cost-effective and fewer off-target side effects, and reversibility potential. Such noticeable features make this technology a unique drug-free approach for diagnosis and treatment of cancer. It can be used to control tumor cells, which is a favorable technique to investigate the heterogeneous and complex features of cancerous cells. Remarkably, optogenetics approaches can provide us with outstanding tool to extend our understanding of how cells perceive, respond, and behave in meeting with complex signals, particularly in terms of cancer evasion from the anticancer immune system functions.

Multifunctional Magnetic Nanoparticles for MRI-guided Co-delivery of Erlotinib and L-Asparaginase to Ovarian Cancer

AIM(S)

The use of magnetic nanoparticles (MNPs) in biomedical applications has been wildly opted due to their unique properties. The objective of this study was to evaluate the effects of aptamer-armed MNPs in ovarian cancer treatment and as T2 weighted MRI contrast agent.

METHODS

Here, we designed MNPs loaded with erlotinib (ERL/SPION-Val-PEG) and conjugated them with anti-mucin16 (MUC16) aptamer to introduce new image-guided nanoparticles (NPs) for targeted drug delivery as well as non-invasive magnetic resonance imaging (MRI) contrast agents. Also, the combination of our nanosystem (NS) along with L-Asparaginase (L-ASPN) led to synergistic effects in terms of reducing cell viability in ovarian cancer cells, which could suggest a novel combination therapy.

RESULTS

The mean size of our NS was about 63.4 ± 3.4 nm evaluated by DLS analysis and its morphology was confirmed using TEM. Moreover, the functional groups, as well as magnetic properties of our NS, were examined by FT-IR and VSM tests, respectively. The loading efficacy of erlotinib on MNPs was about 80% and its release reached 70.85% over 7 days in the pH value of 5.4. The MR images and flow cytometry results revealed that the cellular uptake of ERL/SPION-Val-PEG-MUC16 NPs in cells with MUC16 overexpression was considerably higher than unarmed NPs. In addition, T2-weight MR images of ovarian cancer-bearing mice indicated significant signal intensity changes at the tumor site 4 h after intravenous injection compared to the non-target MNPs.

CONCLUSIONS

Our data suggest ERL/SPION-Val-PEG NPs as an image-guided co-drug delivery system for ovarian cancer.

Synthesis and biological impacts of pollen shells/Fe3O4 nanoparticles composites on human MG-63 osteosarcoma cells

INTRODUCTION

Cell-adhesive surfaces play a pivotal role in biomedical engineering, as most biological reactions take place on surfaces. Pollen shell (PSh) ofPistacia vera L., as a new medical device, has previously been reported to cause cytotoxicity and apoptosis in MG-63 bone cancer cells.

METHODS

Iron oxide nanoparticles (Fe3O4NPs) were synthesized and their reaction to PShs was gauged at different concentrations, and then characterized using field emission scanning electron microscopy (FESEM), Fourier-transform infrared spectroscopy, energy dispersion X-ray spectrometer, X-ray diffraction spectra, dynamic light scattering, and vibrating sample magnetometer. Then, the biological impacts of PShs/Fe3O4NPs composites on MG-63 cells were investigated in-vitro using MTT assay, quantitative polymerase chain reaction (qPCR), Annexin V/propidium iodide, FESEM, and DAPI staining.

RESULTS

Fe3O4NPs with a size range of 24-40 nm and a zeta potential value of -37.4 mV were successfully assembled on the PShs. The viability of MG-63 cells was significantly decreased when cultured on the magnetic PShs as compared to non-magnetic PShs, in Fe3O4 concentration and time-dependent manner. In contrast, magnetic PShs had a positive effect on the viability of normal human bone marrow-derived mesenchymal stem cells (hBM-MSCs). The analysis of apoptosis-related genes in cancer cells revealed that loading Fe3O4NPs on PShs increased expression of BAX/BCL2 and caspase-3 genes. The increased apoptotic activity of combined PShs/Fe3O4NPs was further confirmed by flow cytometric measurement, morphological analysis, and DAPI staining.

CONCLUSION

The incorporation of Fe3O4NPs into PShs could effectively increase anticancer effects on MG-63 cells via the mitochondria-mediated apoptosis pathway, evident by upregulation of BAX/BCL2 ratio and caspase-3.

Bioactive Chitosan-Based Organometallic Scaffolds for Tissue Engineering and Regeneration

Captivating achievements in developing advanced hybrid biostructures through integrating natural biopolymers with inorganic materials (e.g., metals and metalloids) have paved the way towards the application of bioactive organometallic scaffolds (OMSs) in tissue engineering and regenerative medicine (TERM). Of various biopolymers, chitosan (CS) has been used widely for the development of bioactive OMSs, in large part due to its unique characteristics (e.g., biocompatibility, biodegradability, surface chemistry, and functionalization potential). In integration with inorganic elements, CS has been used to engineer advanced biomimetic matrices to accommodate both embedded cells and drug molecules and serve as scaffolds in TERM. The use of the CS-based OMSs is envisioned to provide a new pragmatic potential in TERM and even in precision medicine. In this review, we aim to elaborate on recent achievements in a variety of CS/metal, CS/metalloid hybrid scaffolds, and discuss their applications in TERM. We also provide comprehensive insights into the formulation, surface modification, characterization, biocompatibility, and cytotoxicity of different types of CS-based OMSs.

Exosomes as versatile nanoscaled biocompartments in cancer therapy and/or resistance

Cancer remains to be a major hurdle to global health. Exosomes as a versatile bio-derived platform, hold a bright prospect in nano-scaled delivery/targeting strategies. Shreds of evidence indicate that exosomes have a critical role in drug resistance in cancer cells through various mechanisms including shuttling of miRNAs, drug efflux transporters, and anti-apoptotic signaling. Exosomes' cargo, particularly miRNAs, may exert both resistance and in a few cases sensitivity to the anticancer agents in targeted cells. Therefore, the source and components of the exosomes should be carefully considered before any application. Our aim in this editorial is to further highlight the role of exosomes in the development of resistance to therapy in cancer cells. As a new chapter for drug delivery, the challenges should be elucidated before exosomes emerge as novel nanoplatforms for cancer therapy.

TEM1-targeting PEGylated PLGA shikonin nanoformulation for immunomodulation and eradication of ovarian cancer

Introduction: Tumor endothelial marker 1 (TEM1) is expressed by tumor vascular endothelial cells in various cancers. Methods: Here, we developed poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) PEGylated with polyethylene glycol (PEG) and functionalized with anti-TEM1 antibody fragment (78Fc) and loaded them with necroptosis-inducing agent shikonin (SHK) (78Fc-PLGA-SHK NPs). Results: The nanoformulation showed a smooth spherical shape (~120 nm; the ζ potential of -30 mV) with high drug entrapment and bioconjugation efficiencies (~92% and ~90%, respectively) and a sustained-release profile in serum. Having significant toxicity in vitro (e.g., MS1 and TC1 cells), the nanoformulation dramatically increased the cytotoxicity in the TC1 murine lung carcinoma subcutaneous and intravenous/metastatic models as aggressive tumor models. The injection of the 78Fc-PLGA-SHK NPs to the MS1-xenograft mice resulted in significantly higher accumulation and effects in the TEM1-positive tumor targets, while they were excreted via urine track without retaining in the liver/spleen. In the TC1 subcutaneous model, C57/BL6 mice treated with the 78Fc-PLGA-SHK NPs revealed a significant therapeutic effect. The mice, which were tumor-free after receiving the nanoformulation, were re-challenged with the TC1 cells to investigate the immune response. These animals became tumor-free a week after the injection of TC1 cells. Conclusion: Based on these findings, we propose the 78Fc-PLGA-SHK NPs as a highly effective immunostimulating nanomedicine against the TEM1-expressing cells for targeted therapy of solid tumors including ovarian cancer.

Biocompatibility Evaluation of Hollow Pollen Grains/Fe3 O4 Nanoparticles Composites as Potential Medical Devices

Recently, pollen grains (PGs) have been introduced as drug carriers and scaffolding building blocks. This study aimed to assess the in-vitro biocompatibility of Pistacia vera L. hollow PGs/Fe3O4 nanoparticles (HPGs/Fe3O4NPs) composites using human adipose-derived mesenchymal stem cells (hAD-MSCs). In this regard, iron oxide nanoparticles (Fe3O4NPs) were assembled on the surface of HPGs at different concentrations. The biocompatibility of the prepared composites was assessed through MTT assay, apoptosis-related gene expression and field emission scanning electron microscopy (FE-SEM) analysis. Compared to the bare HPGs, the HPGs/Fe3O4NPs exhibited a biphasic impact on hAD-MSCs. The composite containing 1% Fe3O4NPs demonstrated no cytotoxicity up to 21 days while higher Fe3O4NPs contents and long-term exposure revealed adverse effects on the hAD-MSCs’ growth. The obtained result was verified by the qRT-PCR and morphological analysis carried out through FE-SEM which suggests that a narrow region below 1% Fe3O4NPs may be the optimum choice for medicinal applications of HPGs/Fe3O4NPs microdevices.

Impacts of oxidants and antioxidants on the emergence and progression of Alzheimer's disease

The brain shows a high sensitivity to oxidative stress (OS). Thus, the maintenance of homeostasis of the brain regarding the reduction-oxidation (redox) situation is crucial for the regular function of the central nervous systems (CNS). The imbalance between the reactive oxygen species (ROS) and the cellular mechanism might lead to the emergence of OS, causing profound cell death as well as tissue damages and initiating neurodegenerative disorders (NDDs). Characterized by the cytoplasmic growth of neurofibrillary tangles and extracellular β-amyloid plaques, Alzheimer's disease (AD) is a complex NDD that causes dementia in adult life with severe manifestations. Nuclear factor erythroid 2-related factor 2 (NRF2) is a key transcription factor that regulates the functional expression of OS-related genes and the functionality of endogenous antioxidants. In the case of oxidative damage, NRF2 is transferred to the nucleus and attached to the antioxidant response element (ARE) that enhances the sequence to initiate transcription of the cell-protecting genes. This review articulates various mechanisms engaged with the generation of active and reactive species of endogenous and exogenous oxidants and focuses on the antioxidants as a body defense system regarding the NRF2-ARE signaling path in the CNS.

Hollow pollen grains as scaffolding building blocks in bone tissue engineering

Introduction: The current study, for the first time, suggests nature-made pollen grains (PGs) of Pistacia vera L. as a potential candidate for using as scaffolding building blocks with encapsulation capability of bioactive compounds, such as bone morphogenetic protein 4 (BMP4).

Methods: A modified method using KOH (5%, 25ºC) was developed to produce nonallergic hollow pollen grains (HPGs), confirmed by energy dispersive X-ray (EDX) analysis, field emission scanning electron microscopy (FESEM), and DNA and protein staining techniques. The in-vitro study was conducted on human adipose-derived mesenchymal stem cells (hAD-MSCs) to investigate the applicability of HPGs as bone scaffolding building blocks. Cytocompability was evaluated by FESEM, MTT assay, and gene expression analysis of apoptotic markers (BAX and BCL2). The osteoconductive potential of HPGs was assessed by alkaline phosphatase (ALP) activity measurement and gene expression analysis of osteogenic markers (RUNX2 and osteocalcin).

Results: Findings demonstrated that HPGs can be considered as biocompatible compounds increasing the metabolic activities of the cells. Further, the bioactive nature of HPGs resulted in suitable cellular adhesion properties, required for a potent scaffold. The investigation of apoptotic gene expression indicated a reduced BAX/BCL2 ratio reflecting the protective effect of HPGs on hAD-MSCs. The increased ALP activity and expression of osteogenic genes displayed the osteoconductive property of HPGs. Moreover, the incorporation of BMP4 in HPGs initiated a synergistic effect on osteoblast maturation.

Conclusion: Owing to the unique compositional and surface nanotopographical features of the Pistacia vera L. HPG, this microscale architecture provides a favorable microenvironment for the bottom-up remodeling of bone.

Targeted combined therapy in 2D and 3D cultured MCF-7 cells using metformin and erlotinib-loaded mesoporous silica magnetic nanoparticles

AIM

This research aims to develop potential therapeutic nanostructures (NSs) encapsulating metformin (MET) and erlotinib (ER) for combinational therapy in breast cancer.

METHODS

The ER and MET, both were loaded on mesoporous silica magnetic nanoparticles conjugated with polyethylene glycol and methotrexate to achieve targeted NSs. The developed NSs were characterised using SEM, DLS, and FTIR. Afterward, MTT, Trypan blue, and DNA extraction assays were operated for biological evaluations in the 2D and 3D MCF-7 cells.

RESULTS

Physicochemical approaches indicated the mean diameter of 69.4 nm ± 9.5 (PDI = 0.64), and neutral charge (2 mv) for the developed NSs. MET and ER-loaded NSs exhibited 62.56% ± 4.41 and 67.73% ± 3.03 drug release amount in pH = 5.4, respectively. MTT assay revealed that ER- and MET-loaded NSs had less metabolic activity (≈ 20%) in comparison with non-targeted NSs.

CONCLUSION

Overall, our combined ER and MET-loaded targeted NSs result in a synergistic inhibitory impact on MCF-7 cells.

Stimuli-responsive graphene oxide and methotrexate-loaded magnetic nanoparticles for breast cancer-targeted therapy

Aim: Nanocomposites of graphene oxide (GO) loaded with PEGylated superparamagnetic iron oxide nanoparticles and grafted with methotrexate and stimuli-responsive linkers (GO-SPION-MTX) were developed for photothermal and chemotherapy of breast cancer. Methods: PEGylated SPIONs were synthesized and conjugated with chemotherapeutic targeting agent MTX, which were then loaded on GO to prepare GO-SPION-MTX nanocomposites. To evaluate the photothermal effect of the nanocomposites, they were examined in breast cancer cell lines with low doses of near-infrared (NIR) laser radiation with/without acetazolamide. Results: The GO-SPION-MTX nanocomposites were found to be internalized by the folate-receptor-positive cancer cells and induce high cytotoxicity on exposure to NIR laser rays. Conclusion: Our findings suggest that the GO-SPION-MTX nanocomposite can potentially be used as a multimodal nanomedicine/theranostic against breast cancer.

Folate receptor-mediated delivery of 1-MDT-loaded mesoporous silica magnetic nanoparticles to target breast cancer cells

Aims: The efficiency of mesoporous silica magnetic nanoparticles (MSMNP) as a targeted drug-delivery system was investigated. Methods: The superparamagnetic iron oxide nanoparticles (NP) were synthesized, coated with mesoporous silica and conjugated with polyethylene glycol and methotrexate. Next, 1-methyl-D-tryptophan was loaded into the prepared nanosystems (NS). They were characterized using transmission electron microscopy, scanning electron microscopy, dynamic light scattering, vibrating sample magnetometer, x-ray powder diffraction, Fourier transform-infrared spectroscopy and the Brunauer-Emmett-Teller method and their biological impacts on breast cancer cells were evaluated. Results: The prepared NSs displayed suitable properties and showed enhanced internalization by folate-receptor-expressing cells, exerting efficient cytotoxicity, which was further enhanced by the near-infrared radiation irradiation. Conclusion: On the basis of our findings, the engineered NS is a promising multifunctional nanomedicine/theranostic for solid tumors.

Antibacterial and Cellular Behaviors of Novel Zinc-Doped Hydroxyapatite/Graphene Nanocomposite for Bone Tissue Engineering

Bacteria are one of the significant causes of infection in the body after scaffold implantation. Effective use of nanotechnology to overcome this problem is an exciting and practical solution. Nanoparticles can cause bacterial degradation by the electrostatic interaction with receptors and cell walls. Simultaneously, the incorporation of antibacterial materials such as zinc and graphene in nanoparticles can further enhance bacterial degradation. In the present study, zinc-doped hydroxyapatite/graphene was synthesized and characterized as a nanocomposite material possessing both antibacterial and bioactive properties for bone tissue engineering. After synthesizing the zinc-doped hydroxyapatite nanoparticles using a mechanochemical process, they were composited with reduced graphene oxide. The nanoparticles and nanocomposite samples were extensively investigated by transmission electron microscopy, X-ray diffraction, and Raman spectroscopy. Their antibacterial behaviors against Escherichia coli and Staphylococcus aureus were studied. The antibacterial properties of hydroxyapatite nanoparticles were found to be improved more than 2.7 and 3.4 times after zinc doping and further compositing with graphene, respectively. In vitro cell assessment was investigated by a cell viability test and alkaline phosphatase activity using mesenchymal stem cells, and the results showed that hydroxyapatite nanoparticles in the culture medium, in addition to non-toxicity, led to enhanced proliferation of bone marrow stem cells. Furthermore, zinc doping in combination with graphene significantly increased alkaline phosphatase activity and proliferation of mesenchymal stem cells. The antibacterial activity along with cell biocompatibility/bioactivity of zinc-doped hydroxyapatite/graphene nanocomposite are the highly desirable and suitable biological properties for bone tissue engineering successfully achieved in this work.

Recent advances in breast cancer immunotherapy: The promising impact of nanomedicines

Breast cancer (BC) is one of the prevalent cancers among women. Generally, the treatment of BC is mostly based on several prominent strategies, including chemotherapy, surgery, endocrine therapy, molecular targeted therapy, and radiation. Owing to the growing knowledge about the complexity of BC pathobiology, immunotherapy as a promising treatment modality has substantially improved the patients' care in the clinic. Immunotherapy is used to harness the patient's immune system to recognize and battle devious cancer cells. As a novel therapy approach, this emerging strategy targets the key molecular entities of tumor tissue. To achieve maximal therapeutic impacts, the dynamic interplay between cancer and immune cells needs to be fully comprehended. The key molecular machinery of solid tumors can be targeted by nanoscale immunomedicines. While discussing the potential biomarkers involved in the initiation and progression of BC, we aimed to provide comprehensive insights into the immunotherapy and articulate the recent advances in terms of the therapeutic strategies used to control this disease, including immune checkpoint inhibitors, vaccines, chimeric antigen receptor T cells therapy, and nanomedicines.

Astaxanthin protects mesenchymal stem cells from oxidative stress by direct scavenging of free radicals and modulation of cell signaling

Recent evidence has shown that mesenchymal stem cells (MSCs) play vital roles in cell therapy of ischemia/hypoxia damaged tissues. However, after the transplantation, they might undergo apoptosis due to oxidative stress. Thus, some strategies have been developed to support stem cells in harsh conditions, including pre-treatment of the cells with antioxidants. Of various antioxidants, in this study, astaxanthin (ATX) was used to protect adipose-derived MSCs against oxidative stress. The MSCs were exposed to different doses of hydrogen peroxide, and then the expression of key genes involved in the redox signaling pathway was studied, including nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and NADPH quinine oxidoreductase 1 (NQO1). The balance of intracellular reactive oxygen species was detected with the H2DCFDA molecular probe. Additionally, for the detection of apoptosis and protective effect of ATX, the DAPI/Phallacidin and annexin V cell staining were performed. The results of cellular studies revealed that ATX reduced the H₂O₂-induced cell apoptosis and oxidative stress. Furthermore, after the induction of oxidative stress, the cells' native antioxidants (HO-1 and NQO1) were overexpressed but they were modulated with ATX treatments (p < 0.023). Based on our findings, ATX could increase the expression of Nrf2 as a key transcription factor of antioxidant enzymes (p < 0.05). These findings support the notion that ATX can act as an effective antioxidant in the pre-treatment of MSCs before cell therapy. Thus, to enhance the viability of stem cells during the transplantation in harsh conditions, the concurrent use of ATX in cell therapy modalities is proposed.

Role of cellulose family in fibril organization of collagen for forming 3D cancer spheroids: In vitro and in silico approach

Introduction: Cell aggregation of three-dimensional (3D) culture systems (the so-called spheroids) are designed as in vitro platform to represent more accurately the in vivo environment for drug discovery by using semi-solid media. The uniform multicellular tumor spheroids can be generated based on the interaction of cells with extracellular matrix (ECM) macromolecules such as collagen and integrin. This study aimed to investigate the possible interactions between the cellulose family and collagen using both in vitro and in silico approaches. Methods: The 3D microtissue of JIMT-1 cells was generated using hanging drop method to study the effects of charge and viscosity of the medium containing cellulose family. To determine the mode of interaction between cellulose derivatives (CDs) and collagen-integrin, docking analysis and molecular simulation were further performed using open source web servers and chemical simulations (GROMACS), respectively. Results: The results confirmed that the addition of CDs into the 3D medium can promote the formation of solid spheroids, where methylcellulose (MC) yielded uniform spheroids compared to carboxymethyl cellulose (CMC). Moreover, the computational analysis showed that MC interacted with both integrin and collagen, while sodium carboxymethyl cellulose (NaCMC) only interacted with collagen residues. The stated different behaviors in the 3D culture formation and collagen interaction were found in the physicochemical properties of CDs. Conclusion: Based on in vitro and in silico findings, MC is suggested as an important ECM-mimicking entity that can support the semi-solid medium and promote the formation of the uniform spheroid in the 3D culture.

Smart stimuli-responsive biopolymeric nanomedicines for targeted therapy of solid tumors

Solid tumors form a permissive microenvironment with irregular features, including high pressured tumor interstitial fluid with acidic pH, co-adaptation of cancer cells with other cells like the immune system cells, abnormal metabolism and anomalous overexpression of various pieces of molecular machinery. The functional expressions of several oncomarkers in different solid tumors have led to the development of targeted drug-delivery systems (DDSs). As a new class of DDSs, stimuli-responsive nanomedicines (SRNMs) have been developed using advanced nanobiomaterials such as biopolymers that show excellent biocompatibility with low inherent immunogenicity. In this review, we aim to overview different types of SRNMs, present deep insights into the stimuli-responsive biopolymers and discuss the most up-to-date progress in the design and development of SRNMs used as advanced DDSs for targeted therapy of cancer.

BioImpacts: An emerging global journal

The toddling BioImpacts has now grown into a young adult with strong opinions and perspectives, to a high-quality journal, and it has not been raised but by a family of professional editors, reviewers, authors, and even readers who had fantasized about a bright future and that fantasies are now coming true one-by-one.

COVID-19 clinical implications: the significance of nanomedicine

COVID-19 pandemic has profoundly affected the lives of humans worldwide. We no longer experience the same quality of life and need to come up with effective solutions to combat the clinical implications. The vast knowledge about the pathways that regulate the virus entry and molecular signaling of the pathogenesis of coronavirus are the key factor for the development of de novo diagnostic/therapeutic strategies. Meanwhile, the emergence of nanotechnology, could offer enormous help in the battle against coronavirus. In this editorial, the role of molecular elements in the pathobiology of the disease and the significance of nanoscaled pharmaceuticals is highlighted.

Bioactive polymeric scaffolds for osteogenic repair and bone regenerative medicine

The loss of bone tissue is a striking challenge in orthopedic surgery. Tissue engineering using various advanced biofunctional materials is considered a promising approach for the regeneration and substitution of impaired bone tissues. Recently, polymeric supportive scaffolds and biomaterials have been used to rationally promote the generation of new bone tissues. To restore the bone tissue in this context, biofunctional polymeric materials with significant mechanical robustness together with embedded materials can act as a supportive matrix for cellular proliferation, adhesion, and osteogenic differentiation. The osteogenic regeneration to replace defective tissues demands greater calcium deposits, high alkaline phosphatase activity, and profound upregulation of osteocalcin as a late osteogenic marker. Ideally, the bioactive polymeric scaffolds (BPSs) utilized for bone tissue engineering should impose no detrimental impacts and function as a carrier for the controlled delivery and release of the loaded molecules necessary for the bone tissue regeneration. In this review, we provide comprehensive insights into different synthetic and natural polymers used for the regeneration of bone tissue and discuss various technologies applied for the engineering of BPSs and their physicomechanical properties and biological effects.

Antisense LNA-loaded nanoparticles of star-shaped glucose-core PCL-PEG copolymer for enhanced inhibition of oncomiR-214 and nucleolin-mediated therapy of cisplatin-resistant ovarian cancer cells

We aimed to inhibit overexpressed oncomiR-214 in cisplatin (CIS)-resistant ovarian cancer (OC) and perform targeted therapy of sensitized cells using a novel polymeric drug delivery system (DDS). A system of nanoparticles (NPs) of star-shaped glucose-core polycaprolactone-polyethylene glycol (Glu-PCL-PEG) block copolymer containing cisplatin (CIS-PCL NPs) and locked nucleic acid (LNA) anti-miR-214 (LNA-PCL NPs) were prepared and anti-nucleolin aptamer was conjugated to the surface of prepared NPs to prepare Ap-CIS-PCL NPs and Ap-LNA-PCL NPs, respectively. The cancer-targeting ability of the NPs was confirmed and the CIS-resistant A2780 (A2780 R) cells were transfected with Ap-LNA-PCL NPs to inhibit oncomiR-214 and sensitize the cells to CIS. Next, the miR-214-inhibited cells were exposed to the Ap-CIS-NPs and the deracination efficiency of targeted DDS was evaluated. The oncomiR-214 in A2780 R cells were harnessed by Ap-LNA-PCL NPs, and nucleolin-mediated endocytosis of targeted polymeric DDSs containing CIS into miR-214-inhibited A2780 R cells caused enhanced apoptosis, which was further confirmed by apoptosis detection and evaluation of downstream genes expression. Targeted inhibition of miR-214 using the developed NPs containing LNA can decrease drug-resistant properties of cancer cells and may enhance the efficiency of targeted DDSs.

Formulation and Evaluation of Eudragit RL-100 Nanoparticles Loaded In-Situ Forming Gel for Intranasal Delivery of Rivastigmine

Purpose: Rivastigmine hydrogen tartrate (RHT) is commonly used for the treatment of mild to moderate Alzheimer’s disease (AD). The aim of this work was to formulate in-situ pluronic F-127 (PF-127) hydrogels containing Eudragit RL-100 (EU-RL) nanoparticles (NPs) in order to improve the therapeutic efficacy of RHT through the nasal route.

Methods: The NPs were prepared using different polymer to drug ratios and evaluated for their physicochemical characteristics, cellular uptake and in vitro cytotoxicity against lung adenocarcinoma cells (A459). PF-127 nanoformulations were prepared via cold method and analyzed in terms of physicochemical properties and drug release profiles. The nanoformulations and plain drug gel were then assessed by ex vivo permeation studies across the sheep nasal mucosa.

Results: The EU-RL NPs exhibited a particle size within the range of 118 to 154 nm and positive zeta potential values of 22.5 to 30 mV with an approximately spherical shape. Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and X-ray powder diffraction (XRPD) suggested no drug to polymer interaction through the preparation of nanoformulations. The RHT-loaded NPs exhibited an acceptable cytocompatibility with a time- and dose-dependent cellular internalization.

Conclusion: Our results clearly indicated the potential of nanoformulations as controlled release systems to improve the therapeutic efficacy of RHT through the intranasal administration

Therapeutic impacts of enzyme-responsive smart nanobiosystems

An important arena of the sophisticated nanosystems (NSs) is the combination of the responsive features of NSs with the biocatalytic properties of enzymes. The development of such smart drug delivery systems (DDSs) has seminal effectiveness in targeting, imaging, and monitoring of cancer. These NSs can exhibit site-specific delivery of the toxic cargo in response to the endogenous/exogenous stimuli. Enzyme responsive/targeted DDSs display enhanced accumulation of cargo molecules in the tumor microenvironment (TME) with a spatiotemporal controlled-release behavior. Based on the unique features of enzyme responsive/targeted DDSs, they offer incredible promise in overcoming some limitations of the currently used conventional DDSs. Taken all, targeting TME with the enzyme-responsive targeted DDSs may lead to versatile clinical outcomes in various malignancies.

Aptamedicine: a new treatment modality in personalized cancer therapy

Aptamers ( Aps ) are short single-strand nucleic acids exhibiting unique 3D structure which facilitate their targeting potential against various cancer molecular markers ( CMMs ). Such features of Aps not only make them as suitable homing agents in targeted drug delivery systems (DDSs) but also candidate them as macromolecules that inhibit the interaction of the target ligand with other proteins. On the other hand, the conjugation of Aps with another therapeutic molecule such as antisense oligonucleotides (ASOs), siRNAs/miRNAs, Aps , toxins, chemotherapeutic agents, DNAzymes/Ribozymes provides hopeful strategy to eradicate the malignancies and overcome the off-target unwanted side effects. Such prominent features of Aps make them a promising treatment modality to overcome the tumor complexity and heterogeneity, which can be consequently applied for personalized therapy of cancer by using bispecific Ap-based therapeutics.

PEGylated gold nanoparticles-ribonuclease induced oxidative stress and apoptosis in colorectal cancer cells

Introduction: Currently, drug-induced reactive oxygen species (ROS) mediating apoptosis pathway have extensively been investigated in designing effective strategies for colorectal cancer (CRC) chemotherapy. Bovine pancreatic ribonuclease A (RNase A) represents a new class of cytotoxic and non-mutagenic enzymes, and has gained more attention as a potential anticancer modality; however, the cytosolic ribonuclease inhibitors (RIs) restrict the clinical application of this enzyme. Nowadays, nanotechnology-based diagnostic and therapeutic systems have provided potential solutions for cancer treatments.

Methods: In this study, the gold nanoparticles (AuNPs) were synthesized, stabilized by polyethylene glycol (PEG), functionalized, and covalently conjugated with RNase A. The physicochemical properties of engineered nanobiomedicine (AuNPs-PEG-RNase A) were characterized by scanning electron microscope (SEM), dynamic light scattering (DLS), and UV-vis spectrum. Then, its biological impacts including cell viability, apoptosis, and ROS production were evaluated in the SW-480 cells.

Results: The engineered nanobiomedicine, AuNPs-PEG-RNase A, was found to effectively induce apoptosis in SW-480 cells and result in a significant reduction in cancer cell viability. Besides, the maximum production of ROS was obtained after the treatment of cells with an IC50 dose of AuNPs-PEG-RNase A.

Conclusion: Based on the efficient ROS-responsiveness and the anticancer activity of RNase A of the engineered nanomedicine, this nanoscaled biologics may be considered as a potential candidate for the treatment of CRC.

Lactobacillus plantarum induces apoptosis in gastric cancer cells via modulation of signaling pathways in Helicobacter pylori

Introduction: Gastric cancer is considered the second prevalent cause of death around the world. This type of cancer is generally induced by Helicobacter pylori which could colonize within the gastric mucosa of the infected cases. To date, triple antibiotic therapy has routinely been utilized for controlling the H. pylori- induced infection. However, this strategy has been unsuccessful, in large part because of issues such as occurring point mutations in the H. pylori genome that can induce resistance to the antibiotics administered. Recently, it has been shown that different probiotics may have strong anti-cancer effects, in which they are capable of inhibiting H. pylori by both immunological and non-immunological mechanisms. Here, we aimed at finding possible anti-cancer impacts of the probiotic bacterium Lactobacillus plantarum on gastric cancer, AGS cells. Methods: The anti-cancer effects of the conditioned media of the locally isolated L. plantarum on the AGS cells were evaluated by different analyses such as flow cytometry, DNA ladder assay, DAPI staining, and RT-PCR. Results: Our findings showed that the conditioned media of L. plantarum can inhibit both H. pylori and AGS cells through up-/down-regulation of PTEN, Bax, TLR4, and AKT genes. The exudates of the probiotic L. plantarum bacteria can increase the expression of PTEN, Bax, and TLR4, and also decrease the expression of AKT gene. Conclusion: In agreement with different reports, our results proved the anti-cancer effects of the locally isolated L. plantarum through some immunological cell signaling pathways. Accordingly, it seems the probiotics could be considered as at least a complementary treatment for different types of malignancies.

Targeted delivery of doxorubicin by magnetic mesoporous silica nanoparticles armed with mucin-1 aptamer

Distinctive physicochemical features make mesoporous silica magnetic nanoparticles (SPION@SiO₂) as a multifunctional nanosystem (NS) for the targeted delivery of therapeutic agents. In the present study, we engineered the mucin-1 (MUC-1) conjugated SPION@SiO₂ (SPION@SiO₂-MUC-1) for the targeted delivery of doxorubicin (DOX) to the breast cancer cells. Superparamagnetic iron oxide nanoparticles (SPIONs) were synthesised using thermal decomposition technique, and then, coated with mesoporous silica to modify their biocompatibility and reduce undesired cytotoxic effects. Subsequently, DOX was loaded onto the silica porous structures, which was then nanoparticles (NPs) grafted with 5'-amine-modified MUC-1 aptamers. Transmission electron microscopy and particle size analysis by differential light scattering exhibited spherical and monodisperse NPs with a size range of 5-27 nm. The FT-IR spectroscopy confirmed the surface modification of the engineered NS. The surface area and pore size of the SPION@SiO₂-COOH NSs were calculated by BJH and BET calculations. The MTT assay revealed higher cytotoxicity of MUC-1 grafted SPION@SiO₂ NSs in the MUC-1-positive MCF-7 cells as compared to the control MUC-1-negative MDA-MB-231 cells. The flow cytometry analysis of the SPION@SiO₂-MUC-1 NSs revealed a higher uptake as compared to the non-targeted nanocomposite (NC) in MCF-7 cells. In conclusion, the engineered SPION@SiO₂-MUC-1 NS is proposed to serve as an effective multifunctional targeted nanomedicine/theranostics against MUC-1 overexpressing cancer cells.