From stem cells to extracellular vesicles: a new horizon in tissue engineering and regenerative medicine.

In the fields of tissue engineering and regenerative medicine, extracellular vesicles (EVs) have become viable therapeutic tools. EVs produced from stem cells promote tissue healing by regulating the immune system, enhancing cell proliferation and aiding remodeling processes. Recently, EV has gained significant attention from researchers due to its ability to treat various diseases. Unlike stem cells, stem cell-derived EVs show lower immunogenicity, are less able to overcome biological barriers, and have a higher safety profile. This makes the use of EVs derived from cell-free stem cells a promising alternative to whole-cell therapy. This review focuses on the biogenesis, isolation, and characterization of EVs and highlights their therapeutic potential for bone fracture healing, wound healing, and neuronal tissue repair and treatment of kidney and intestinal diseases. Additionally, this review discusses the potential of EVs for the treatment of cancer, COVID-19, and HIV. In summary, the use of EVs derived from stem cells offers a new horizon for applications in tissue engineering and regenerative medicine.

Development and In-Vitro Evaluation of Eugenol-Based Nanostructured Lipid Carriers for Effectual Topical Treatment Against C. albicans.

The main objective of the experiment is to develop and evaluate hydrogel-bearing nanostructured lipid carriers (NLCs) loaded with ketoconazole (KTZ) for the effective treatment of candidiasis. The eugenol was used as a liquid lipid (excipient) for the development of KTZ-loaded NLCs and was explored for anti-fungal effect. The production of NLCs involves high energy processes to generate spherical, uniform particles, having a higher percentage of entrapment efficiency (%EE) for KTZ with 89.83 ± 2.31 %. The data from differential scanning calorimeter (DSC), powder x-ray diffraction (PXRD), and attenuated total reflectance (ATR) demonstrated the KTZ dispersion in NLCs. The NLCs loaded hydrogel possessed optimum spreadability and exhibited shear thinning behavior, indicating the ease of application of the final formulation. The 6.41-fold higher transdermal flux (Jss) was governed for KTZ from KTZ-NLC than coarse-KTZ, which explains the usefulness of NLCs. The KTZ-NLCs exhibited significant 2.58 and 6.35-fold higher retention in the stratum corneum and viable epidermis of the skin. The cell cytotoxicity studies using human dermal fibroblast cell (HDFS) lines depicted the usefulness of NLCs in reducing cell toxicities for KTZ. The KTZ-NLCs were found to inhibit planktonic growth and hyphal transition and showed a larger zone of inhibition against C. albicans strains with a MIC-50 value of 0.39 µg/mL. The antibiofilm activity of KTZ-NLCs at lower concentrations, in contrast to plain KTZ, explained the interaction of developed NLCs with fungal membranes. The overall results depicted the effectiveness of the loading KTZ in the lipid matrix to achieve antifungal activity against C. albicans.

Exosomes: Recent Advances and Challenges as Targeted Therapeutic Delivery Vesicles.

The exosome is a naturally derived nanostructured lipid vesicle that ranges from 40-100 nm in size and is utilized to transport drugs, and biological macromolecules, including therapeutic RNA and proteins. It is a membrane vesicle actively released by cells to transport cellular components with a purpose for biological events. The conventional isolation technique has several drawbacks, including low integrity, low purity, long processing time, and sample preparation. Therefore, microfluidic technologies are more widely accepted for the isolation of pure exosomes, but due to cost and expertise requirements, this technology is also facing challenges. The bioconjugation of small and macro-molecules to the surface of exosomes is a very interesting and emerging approach for achieving the specific target, therapeutic purpose, in vivo imaging, and many more. Although emerging strategies resolve a few challenges, exosomes are still unexplored complex nano-vesicles with excellent properties. This review has briefly elaborated on contemporary isolation techniques and loading approaches. We have also discussed the surface-modified exosomes by different conjugation methods and their applications as targeted drug delivery vesicles. The challenges associated with the exosomes, patents, and clinical investigations are the main highlight of this review.

Lentinan: An unexplored novel biomaterial in drug and gene delivery applications.

Recently, lentinan (LNT) has been utilized for its diversified potential in research with an extended role from nutritional or medicinal applications to a novel biomaterial. LNT is a biocompatible, multifunctional polysaccharide employed as a pharmaceutical additive in engineering customized drug or gene carriers with an improved safety profile. Its triple helical structure containing hydrogen bonding offers more extraordinary binding sites for the attachments of dectin-1 receptors and polynucleotide sequences (poly(dA)). Hence, the diseases expressing dectin-1 receptors can be specifically targeted through so-designed LNT-engineered drug carriers. Gene delivery using poly(dA)-s-LNT complexes and composites has exhibited greater targetability and specificity. The achievement of such gene applications is assessed through the pH and redox potential of the extracellular cell membrane. The steric hindrance-acquiring behavior of LNT shows promise as a system stabilizer in drug carrier engineering. LNT shows viscoelastic gelling behavior temperature-dependently and therefore needs to explore more to meet topical disease applications. The immunomodulatory and vaccine adjuvant properties of LNT help in mitigating viral infections too. This review highlights the new role of LNT as a novel biomaterial, particularly in drug delivery and gene delivery applications. In addition, its importance in achieving various biomedical applications is also discussed.

A review on albumin as a biomaterial for ocular drug delivery.

Development of ocular drug delivery system is one of the most technically challenging tasks, when compared with other routes of drug delivery. Eye (an intricate organ) is highly sophisticated and sensitive organ due to presence of various structurally differed anatomical layers, which many times limits the drug delivery approaches. Despite several limitations, many advancements have been made as evidence from various recent studies involving improvement of both residence time and permeation of the drug at the ocular region. In the last few decades, albumin(s) based ophthalmic products have been gained most attention to solve the major challenges associated with conventional ocular drug delivery systems. Interestingly, an albumin-based micro, nano, conjugates, and genetically fused target specific to ligand(s) formulation being exploited through many studies for successful ocular delivery of bioactives (mostly repurposed drugs). Past and current studies suggested that albumin(s) based ocular drug delivery system is multifunctional in nature and capable of extending both drug residence time and sustaining the release of drugs to deliver desired pharmacological outcomes. Despite wide applications, still complete progress made in albumin based ocular drug delivery is limited in literature and missing in market. So, herein we presented an overview to explore the key concepts of albumin-based nanocarrier(s) including strategies involved in the treatment of ocular disease, that have yet to be explored.

COVID-19 vaccines: rapid development, implications, challenges and future prospects.

COVID-19 has affected millions of people and put an unparalleled burden on healthcare systems as well as economies throughout the world. Currently, there is no decisive therapy for COVID-19 or related complications. The only hope to mitigate this pandemic is through vaccines. The COVID-19 vaccines are being developed rapidly, compared to traditional vaccines, and are being approved via Emergency Use Authorization (EUA) worldwide. So far, there are 232 vaccine candidates. One hundred and seventy-two are in preclinical development and 60 in clinical development, of which 9 are approved under EUA by different countries. This includes the United Kingdom (UK), United States of America (USA), Canada, Russia, China, and India. Distributing vaccination to all, with a safe and efficacious vaccine is the leading priority for all nations to combat this COVID-19 pandemic. However, the current accelerated process of COVID-19 vaccine development and EUA has many unanswered questions. In addition, the change in strain of SARS-CoV-2 in UK and South Africa, and its increasing spread across the world have raised more challenges, both for the vaccine developers as well as the governments across the world. In this review, we have discussed the different type of vaccines with examples of COVID-19 vaccines, their rapid development compared to the traditional vaccine, associated challenges, and future prospects.

Theranostic Potential of Targeted Nanoparticles for Brain Cancer.

Cancer is one of the most important causes of morbidity and mortality all across the world. On an average, every year approximately 238,000 new cases of brain and other central nervous system tumors are diagnosed around the world. Amongst all, tumors of brain account for nearly 85% to 90% of all primary central nervous system (CNS) tumors. Regardless of tremendous scientific efforts to develop newer diagnostic techniques and latest therapy, the management of brain cancer is still a challenge in neuro-oncology. Inadequate concentration of chemotherapeutics at the site of tumor restricts the complete destruction of malignant cells due to the presence of blood brain barrier. Besides, there is a necessity for improvement in tumor imaging for better characterization and visualization of tumor cells for surgical procedure. Nanoparticles offer the advantages upon many of these concerns i.e., diagnosis, capability to target therapeutic agents to the tumor sites and the ability of getting across the blood-brain barrier. Thus utilization of nanoparticles may lead to breakthrough in brain cancer management.

Ano-Genital Warts and HIV Status- A Clinical Study.

INTRODUCTION: Ano-Genital Warts (AGW) like other Sexually Transmitted Diseases (STD) is associated with Human Immunodeficiency Virus (HIV) infection. This study of AGW was done in HIV positive and HIV negative patients. AIM: To study the risk factors and clinical presentations of ano-genital warts in HIV positive and negative patients. MATERIALS AND METHODS: A comparative, cross-sectional, descriptive study of 25 HIV positive and 25 HIV negative (n=50) AGW patients between 15-60 years of both sex was conducted in Dr. D. Y. Patil Hospital and Research Centre from July 2014 to July 2016. RESULTS: Significant association of HIV positivity (p<0.05) was observed between age group of 15-30 years and HIV negative status (p<0.05) in age group of 31-45 years. HIV positive status significantly higher in patients with self-admitted multiple sexual partners (p<0.01), homosexuality (p<0.05) and presentation with anal warts (p<0.01). HIV negative status correlated significantly with single sexual partner admission (p<0.01) and hetero-sexuality (p<0.05). Gender did not show significant association with number of sexual partners or HIV positivity. Extra-genital or only genital warts had no association with HIV status. Co-STDs though more in number in ser-positive group, did not show any significant association with HIV positivity (p>0.05). No patient presented with changes of malignancy. Four were adolescents below 19 years. Two patients had atypical presentations of giant condylomata i.e., Buschke-Lowenstein Tumour (BLT). CONCLUSION: HIV positivity was significantly associated with the risk factors of age below 30 years, homo sexuality and multiple sexual partners. Anal warts were significantly common in HIV positive patients. Four adolescents with AGW underline the need for high risk behaviour counselling. No patient had malignant ano-genital warts. Follow up of these patients with Human Papilloma Virus (HPV) sub-typing is necessary.

Insight to drug delivery aspects for colorectal cancer.

Colorectal cancer (CRC) is the third most common cancer diagnosed worldwide in human beings. Surgery, chemotherapy, radiotherapy and targeted therapies are the conventional four approaches which are currently used for the treatment of CRC. The site specific delivery of chemotherapeutics to their site of action would increase effectiveness with reducing side effects. Targeted oral drug delivery systems based on polysaccharides are being investigated to target and deliver chemotherapeutic and chemopreventive agents directly to colon and rectum. Site-specific drug delivery to colon increases its concentration at the target site, and thus requires a lower dose and hence abridged side effects. Some novel therapies are also briefly discussed in article such as receptor (epidermal growth factor receptor, folate receptor, wheat germ agglutinin, VEGF receptor, hyaluronic acid receptor) based targeting therapy; colon targeted proapoptotic anticancer drug delivery system, gene therapy. Even though good treatment options are available for CRC, the ultimate therapeutic approach is to avert the incidence of CRC. It was also found that CRCs could be prevented by diet and nutrition such as calcium, vitamin D, curcumin, quercetin and fish oil supplements. Immunotherapy and vaccination are used nowadays which are showing better results against CRC.

Development of liposomes entrapped in alginate beads for the treatment of colorectal cancer.

BACKGROUND: Folic Acid conjugated liposomes encapsulating Oxaliplatin (L-OHP) were entrapped in alginate beads and further coated with Eudragit-S-100 for effective delivery to colon tumors. METHODS: Liposomes were prepared by cast film method and folic acid was coupled on the surface of liposomes. They were further entrapped in alginate beads which were Eudragit coated for degradation in the colonic region. The prepared beads were characterized for shape and surface morphology, percentage entrapment efficiency and drug release studies. The in vitro drug release was investigated using a USP dissolution paddle type apparatus in different simulated gastrointestinal fluids. In vivo studies of the beads containing free drug, folic acid coupled and uncoupled liposomes bearing L-OHP was administered orally at the dose of 10mg L-OHP/kg body weight to tumor bearing NUDE/SCID mice. RESULTS: γ-Scintigraphic study showed that Eudragit coated alginate beads entered into the colon of Balb/c mice between 4.20 and 4.50h after oral administration. In vivo data showed that folic acid coupled liposomes entrapped in alginate beads delivered 2.82 ± 0.58 and 21.52 ± 2.76 µg L-OHP/g tissues in the colon and tumor after 12h, reflecting its targeting potential to colon and tumor. CONCLUSION: The results clearly demonstrate that Eudragit coated calcium alginate beads bearing folic acid coupled liposome can be used as a prospective carrier for drug delivery to colon specific tumor.

Eudragit S100 Coated Citrus Pectin Nanoparticles for Colon Targeting of 5-Fluorouracil.

In the present study, Eudragit S100 coated Citrus Pectin Nanoparticles (E-CPNs) were prepared for the colon targeting of 5-Fluorouracil (5-FU). Citrus pectin also acts as a ligand for galectin-3 receptors that are over expressed on colorectal cancer cells. Nanoparticles (CPNs and E-CPNs) were characterized for various physical parameters such as particle size, size distribution, and shape etc. In vitro drug release studies revealed selective drug release in the colonic region in the case of E-CPNs of more than 70% after 24 h. In vitro cytoxicity assay (Sulphorhodamine B assay) was performed against HT-29 cancer cells and exhibited 1.5 fold greater cytotoxicity potential of nanoparticles compared to 5-FU solution. In vivo data clearly depicted that Eudragit S100 successfully guarded nanoparticles to reach the colonic region wherein nanoparticles were taken up and showed drug release for an extended period of time. Therefore, a multifaceted strategy is introduced here in terms of receptor mediated uptake and pH-dependent release using E-CPNs for effective chemotherapy of colorectal cancer with uncompromised safety and efficacy.

Targeting liver cancer via ASGP receptor using 5-FU-loaded surface-modified PLGA nanoparticles.

CONTEXT: Liver cancer is widespread liver malignancy in the world, for an estimated one million deaths annually. OBJECTIVE: In present work, lactobionic acid conjugated PLGA nanoparticles (LDNPs) bearing 5-Fluorouracil (5-FU) were developed for targeted delivery to hepatocellular carcinoma. MATERIALS AND METHODS: Lactobionic acid conjugated PLGA was used to prepare LDNPs using modified emulsion diffusion method. RESULTS: They were characterised for particle morphology, particle size (below 150 nm), zeta potential and polydispersity index (PDI ∼0.35), entrapment efficiency (∼60.23%), and cumulative percent drug release. DISCUSSION: LDNPs in ex-vivo cell line studies on human cancer cell line HepG2 exhibited significantly higher cytotoxicity compared to 5-FU and DNPs (unconjugated PLGA NPs) with growth inhibition 50% (GI50) of 66.7 µg/mL, 50.2 µg/mL and 35.5 µg/mL, respectively. In vivo studies exhibited higher drug concentration about 37.52 ± 0.68% in liver as compared to other organs and plasma. CONCLUSION: Thus, LDNPs showed high drug loading, specificity, biocompatibility and efficacy in treatment of liver cancer.

Low Density Lipid Nanoparticles for Solid Tumor Targeting.

One of the most significant characteristics of cancer cells is their rapid dividing ability and overexpression of LDL receptors, which offers an opportunity for the selective targeting of these cells. 5-Fluorouracil (5-FU)-encapsulated low density lipid nanoparticles (LDLN) were prepared by the emulsion congealing method which mimics the plasma-derived LDL by acquiring the apolipoprotein B-100 from the blood. The average particle size, transmission electron microscope (TEM), and drug content of the prepared LDLN dispersion were found to be 161±3.5 nm, with spherical shape, and 0.370±0.05 mg/mL, respectively. In vitro release studies revealed a sustained profile which decreased with a lapse of time. In vivo studies of 5-FU serum concentration and biodistribution revealed a 5-FU serum concentration of 8.5% in tumor cells and about 2.1% in the liver at the end of 24 hr from LDLN. Tumor growth suppression studies showed 185.42% average tumor growth and 89.76% tumor height as compared to the control exhibiting tumor growth at 1166.47% and tumor height at 176.07%. On the basis of these collective data, it is suggested that a higher accumulation of LDLN, when given as an IV, in solid tumors is attributed to the active uptake of LDLN via LDL receptors via apolipoprotein B-100.

Development and validation of the HPLC method for simultaneous estimation of Paclitaxel and topotecan.

A simple, rapid, accurate and precise high performance liquid chromatography (HPLC) method for simultaneous analysis of Paclitaxel and Topotecan was developed. Different analytical parameters, such as linearity, accuracy, precision, specificity with intentional degradation, limit of detection and limit of quantification (LOQ), were determined according to the ICH guidelines. Acetonitrile-water (70:30, 0.1% trifluoroacetic acid) was run on a Phenomenex Luna C-18(2) column in isocratic mode at a flow rate of 1.2 mL/min for simultaneous analysis of the two drugs using a UV detector set at 227 nm. The proposed method showed a retention time (Rt) of 14.56 min for Topotecan and 23.81 min for Paclitaxel with a continuous run up to 30 min. The linearity of the calibration curves for each analyte in the desired concentration range was found to be good (r(2) > 0.9995). The recovery ranged from 97.9 to 101% for each drug with a relative standard deviation (%RSD) of <2%. Peaks corresponding to each of the drugs exhibited  positive values for the minimum peak purity index over the entire range of integrated chromatographic peak indicating high purity of the peaks. Stability analysis revealed that the drugs remained stable for sufficient time. Thus, the developed method was found to be robust and it can be employed to quantify Paclitaxel and Topotecan in commercial sample and rat blood/serum.

Peptide and protein delivery using new drug delivery systems.

Pharmaceutical and biotechnological research sorts protein drug delivery systems by importance based on their various therapeutic applications. The effective and potent action of the proteins/peptides makes them the drugs of choice for the treatment of numerous diseases. Major research issues in protein delivery include the stabilization of proteins in delivery devices and the design of appropriate target-specific protein carriers. Many efforts have been made for effective delivery of proteins/peptidal drugs through various routes of administrations for successful therapeutic effects. Nanoparticles made of biodegradable polymers such as poly lactic acid, polycaprolactone, poly(lactic-co-glycolic acid), the poly(fumaric-co-sebacic) anhydride chitosan, and modified chitosan, as well as solid lipids, have shown great potential in the delivery of proteins/peptidal drugs. Moreover, scientists also have used liposomes, PEGylated liposomes, niosomes, and aquasomes, among others, for peptidal drug delivery. They also have developed hydrogels and transdermal drug delivery systems for peptidal drug delivery. A receptor-mediated delivery system is another attractive strategy to overcome the limitation in drug absorption that enables the transcytosis of the protein across the epithelial barrier. Modification such as PEGnology is applied to various proteins and peptides of the desired protein and peptides also increases the circulating life, solubility and stability, pharmacokinetic properties, and antigenicity of protein. This review focuses on various approaches for effective protein/peptidal drug delivery, with special emphasis on insulin delivery.

Insulin delivery through nasal route using thiolated microspheres.

The aim of the present study was to investigate the potential of developed thiolated microspheres for insulin delivery through nasal route. In the present study, cysteine was immobilized on carbopol using EDAC. A total of 269.93 µmol free thiol groups per gram polymer were determined. The prepared nonthiolated and thiolated microspheres were studied for particle shape, size, drug content, swellability, mucoadhesion and in vitro insulin release. The thiolated microspheres exhibited higher mucoadhesion due to formation of covalent bonds via disulfide bridges with the mucus gel layer. Drug permeation through goat nasal mucosa of nonthiolated and thiolated microspheres were found as 52.62 ± 2.4% and 78.85 ± 3.1% in 6 h, respectively. Thiolated microspheres bearing insulin showed better reduction in blood glucose level (BGL) in comparison to nonthiolated microspheres as 31.23 ± 2.12% and 75.25 ± 0.93% blood glucose of initial BGL were observed at 6 h after nasal delivery of thiolated and nonthiolated microspheres in streptozotocin-induced diabetic rabbits.

A new horizon in modifications of chitosan: syntheses and applications.

Chitosan is a naturally occurring biopolymer having diversified applications not only in the pharmaceutical field, but also in the biomedical profession. The presence of functional groups, i.e., hydroxyl, acetamido, and amine in the chitosan parent backbone, makes it a suitable candidate for chemical modification, and introduces desired physicochemical and biochemical properties, without any changes in its fundamental skeleton. The various modifications, i.e., alkylation, acylation, quaternization, hydroxyalkylation, carboxyalkylation, thiolation, sulfation, phosphorylation, enzymatic modifications, oligomerization, and graft copolymerization with assorted modifications, and their pharmaceutical and biomedical applications, are discussed in this article. Additionally, it is also limelighted how the chemically engineered chitosan has established a better place with regard to the vista of applications in the arena of sciences such as pharmaceutical, biomedical, biotechnological, tissue engineering, the textile industry, chemistry, the food industry, and many more. This review, hopefully, could enrich knowledge and bring forth new thoughts in line with progress in chitosan polymer science.

Liposomes a vesicular nanocarrier: potential advancements in cancer chemotherapy.

The indispensable obligation behind the successful therapy of a disease is to deliver the effective drug/bioactive concentration with sustained release manner at the diseased organs without any exposure to the healthy tissues. Novel drug-delivery systems increase the concentration and persistence of drug at the vicinity of the target site and thereby minimize the undesired side effects of the drug to the normal tissues of body. With advances in nanotechnology, several new drug delivery approaches have become available that may fulfil the requirement of safe and effective drug therapy. Among these techniques, vesicular drug-delivery systems, particularly liposomes, are under rigorous research for their applicability to deliver FDA-approved and newer drugs. Liposomes have been widely investigated as one of the most widely used nanocarriers in cancer therapy and have shown their potential in spatial and temporal release of bioactive agents for the effective treatment of various life-threatening diseases, including cancer. Various targeted and triggered-release approaches of bioactive substances using liposomes further improve the applicability of liposomes in cancer therapeutics. Thus, keeping these points in view, the present review has been focussed on application of liposomes for development of liposome technology and its novel applications for effective cancer therapy.

Chitosan: a potential polymer for colon-specific drug delivery system.

INTRODUCTION: There is an enormous growth and awareness of the potential applications of natural polymers for colon delivery of therapeutic bioactives. Chitosan (CH), a cationic polysaccharide, has a number of vital applications in the field of colon delivery and has attracted a great deal of attention from formulation scientists, academicians and environmentalists due to its unique properties. AREAS COVERED: CH has been widely explored for the delivery of drugs, peptides, proteins and genes to the colon for different therapeutic applications. Sustained and controlled delivery can be achieved with CH-based formulations like CH-coated tablets, capsules, beads, gels, microparticles and nanoparticles. This review mainly focuses on various aspects of CH-based formulations, particularly development of colon-specific delivery of drug. EXPERT OPINION: The vital properties of CH make it a versatile excipient, not only for sustained/controlled release applications but also as biodegradable, biocompatible, bioadhesive polymer. The colon is recognized as the preferred absorption site for orally administered protein and peptide drugs. The main problem associated with CH is limited solubility at higher pH due to reduced cationic nature, which also reduces mucoadhesiveness. The application of newer targeting moiety with CH-based formulations for highly site-specific delivery of bioactive has to be evaluated for further improvement of therapeutic index (bioavailability).

Development of surface-functionalised nanoparticles for FGF2 receptor-based solid tumour targeting.

The surface-functionalised gelatin nanoparticles (GNPs) containing cisplatin were developed and characterised for breast cancer targeting using fibroblast growth factor-2 (FGF2) receptors which are overexpressed on breast cancer cells. The GNPs were prepared using two-step desolvation method and then the surface of GNPs was functionalised with activated heparin. They were characterised for surface morphology, particle size and size distribution, surface charge, entrapment efficiency and in vitro drug release. The results revealed that the mean diameter of GNPs was 173 ± 2.2 nm with smooth surface, which was increased to 189 ± 3.4 nm after coupling with heparin (H-GNPs). The targeting effect of H-GNPs and GNPs was investigated by in vitro cell uptake study on human breast cancer MDA-MB-231 cell line, which exhibited greater uptake of H-GNPs as compared to GNPs. Therefore, it is suggested that H-GNPs can be used as an effective carrier for solid tumour targeting.