Aerosol Delivery of Paclitaxel-Containing Self-Assembled Nanocochleates for Treating Pulmonary Metastasis: An Approach Supporting Pulmonary Mechanics

Nanostructured lipid carriers (NLCs): A promising candidate for lung cancer targeting

Lung cancer stands as the foremost health issue and the principal reason for mortality worldwide. It is projected that India will see over 1.73 million new cases and more than 880,000 deaths related to cancer, with lung cancer being a significant contributor. The efficiency of existing chemotherapy procedures is not optimal because of less soluble nature and short half-life of anticancer substances. More precipitated toxicity and non-existence of targeting propensity can lead to severe side effects, non-compliance, and inconvenience for patients. Nonetheless, the domain of nanomedicine has undergone a revolution in the past few years with the advent of novel drug delivery mechanisms that tackle the drawbacks of conventional approaches. Diverse nanoparticle-based drug delivery methods, including liposomes, nanoparticles, nanostructured lipid carrier and solid lipid nanoparticle that encapsulated chemotherapy drugs, are currently employed for efficient lung cancer therapy. NLCs, recognized as the second-generation lipid nanocarriers, are a focused drug delivery mechanism that has garnered significant interest owing to their multitude of advantages such as increased stability, minimal toxicity, prolonged shelf life, superior encapsulation capability, and biocompatible nature. This review focuses on the NLCs carrier system, discussing its preparation methods, types, characterization, applications, and future prospects in lung cancer treatment.

Natural Products-Based Inhaled Formulations for Treating Pulmonary Diseases

Given the unique physiological and pathological characteristics of the lung, the direct, inhalable route is more conducive to pulmonary drug delivery and disease control than traditional systemic drug delivery, significantly circumventing drug loss, off-target effects, systemic and organ toxicity, etc., and is widely regarded as the preferred regimen for pulmonary drug delivery. However, very few lung diseases are currently treated with the preferred inhaled formulations, such as asthma, chronic obstructive pulmonary disease and pulmonary hypertension. And there is a lack of appropriate inhaled formulations for other critical lung diseases, such as lung cancer and pulmonary fibrosis, due to the fact that the physicochemical properties of the drugs and their pharmacokinetic profiles do not match the physiology of the lung, and conventional inhalation devices are unable to deliver them to the specific parts of the lung. Phytochemicals of natural origin, due to their wide availability and clear safety profile, hold great promise for the preparation of inhalable formulations to improve the current dilemma in the treatment of lung diseases. In particular, the preparation of inhalable formulations based on nano- and microparticulate carriers for drug delivery to deep lung tissues, which overcome the shortcomings of conventional inhalation therapies while targeting the drug activity directly to a specific part of the lung, may be the best approach to change the current dilemma of lung disease treatment. In this review, we discuss recent advances in nano- and micron-carrier-based inhalation formulations for the delivery of natural products for the treatment of pulmonary diseases, which may represent an opportunity for practical clinical translation of natural products.

Curcumin and quercetin loaded nanocochleates gel formulation for localized application in breast cancer therapy

After surgical excision of breast cancer, chemotherapy is recommended to eradicate any undiagnosed cancer cells and lower the likelihood of the cancer recurring. Curcumin and quercetin are two old flavonoid medicines used to treat breast cancer. Besides ambient popularity, they possess poor water solubility and poor bioavailability, limiting their usefulness. Hence to overcome these limitations, the present research aims to formulate curcumin and quercetin-loaded nanocochleates and convert them into a gel for localized application to enhance the breast cancer treatment. In this research article, we have developed curcumin and quercetin-loaded nanocochleates gel for breast cancer adjuvant therapy. The particle size, zeta potential encapsulation efficiency, and drug release of quercetin nanocochleates were 327 nm, -16.8 mV, 83.28 %, and 80.23 %, respectively, and that of curcumin nanocochleates were 328.6 nm, -15.0 mV, 82.30 %, and 77.19 %, respectively. The quercetin and curcumin-loaded nanocochleates gel was further characterized for pH, spreadability, and viscosity. The in vitro drug release behaviour of gel is controlled compared to plain quercetin and quercetin nanocochleates. The release of quercetin and curcumin from nanocochleates gel was 78.19 %, and 77.19 %, respectively. The MTT assay results showed quercetin and curcumin-loaded nanocochleates have maximum inhibition compared to control, quercetin alone, quercetin liposomes, and quercetin nanocochleates. Thus the quercetin and curcumin combination nanocochleates gel formulation can be a better option for the localized application in the breast cancer treatment.

A Comparative Study of Quercetin-Loaded Nanocochleates and Liposomes: Formulation, Characterization, Assessment of Degradation and In Vitro Anticancer Potential

Quercetin, a flavonoid, has antioxidant and anti-inflammatory properties and the potential to inhibit the proliferation of cancer, but its therapeutic efficacy is lowered due to poor solubility and bioavailability. Quercetin-loaded nanocochleates (QN) were developed using a trapping method by the addition of calcium ions into preformed negatively charged liposomes (QL) prepared by a thin-film hydration method. Liposomes were optimized by varying the concentration of Dimyristoyl phosphatidyl glycerol and quercetin by applying D-optimal factorial design using Design-Expert^® software. Stable rods were observed using TEM with an average particle size, zeta potential and encapsulation efficiency of 502 nm, −18.52 mV and 88.62%, respectively, for QN which were developed from spherical QL showing 111.06 nm, −40.33 mV and 74.2%, respectively. In vitro release of quercetin from QN and QL was extended to 24 h. Poor bioavailability of quercetin is due to its degradation in the liver, so to mimic in vivo conditions, the degradation of quercetin released from QL and QN was studied in the presence of rat liver homogenate (S9G) and results revealed that QN, due to its unique structure, i.e., series of rolled up solid layers, shielded quercetin from the external environment and protected it. The safety and biocompatibility of QL and QN were provenby performing cytotoxicity studies on fibroblast L929 cell lines. QN showed superior anticancer activity compared to QL, as seen for human mouth cancerKB cell lines. Stability studies proved that nanocochleates were more stable than liposomal formulations. Thus, nanocochleates might serve as pharmaceutical nanocarriers for the improved efficacy of drugs with low aqueous solubility, poor bioavailability, poor targeting ability and stability.

Cholesterol Microdomain Enhances the Biofilm Eradication of Antibiotic Liposomes

Resistance and tolerance of biofilms to antibiotics is the greatest challenge in the treatment of bacterial infections. Therefore, developing an effective strategy against biofilms is a top priority. Liposomes are widely used as antibiotic drug carriers; however, common liposomes lack affinity for biofilms. Herein, biofilm-targeted antibiotic liposomes are created by simply adjusting their cholesterol content. The tailored liposomes exhibit significantly enhanced bacterial inhibition and biofilm eradication effects that are positively correlated with the cholesterol content of liposomes. The experiments further demonstrate that this enhanced effect can be ascribed to the effective drug release through the pores, which are formed by the combination of cholesterol microdomains in liposomal lipid bilayers with membrane-damaged toxins in biofilms. Consequently, liposome encapsulation with a high cholesterol concentration improves noticeably the pharmacodynamics and biocompatibility of antibiotics after pulmonary administration. This work may provide a new direction for the development of antibiofilm formulations that can be widely used for the treatment of infections caused by bacterial biofilms.

Aerosol Delivery of Surfactant Liposomes for Management of Pulmonary Fibrosis: An Approach Supporting Pulmonary Mechanics

Excessive architectural re-modeling of tissues in pulmonary fibrosis due to proliferation of myofibroblasts and deposition of extracellular matrix adversely affects the elasticity of the alveoli and lung function. Progressively destructive chronic inflammatory disease, therefore, necessitates safe and effective non-invasive airway delivery that can reach deep alveoli, restore the surfactant function and reduce oxidative stress. We designed an endogenous surfactant-based liposomal delivery system of naringin to be delivered as an aerosol that supports pulmonary mechanics for the management of pulmonary fibrosis. Phosphatidylcholine-based liposomes showed 91.5 ± 2.4% encapsulation of naringin, with a mean size of 171.4 ± 5.8 nm and zeta potential of −15.5 ± 1.3 mV. Liposomes with the unilamellar structure were found to be spherical and homogeneous in shape using electron microscope imaging. The formulation showed surface tension of 32.6 ± 0.96 mN/m and was able to maintain airway patency of 97 ± 2.5% for a 120 s test period ensuring the effective opening of lung capillaries and deep lung delivery. In vitro lung deposition utilizing Twin Stage Impinger showed 79 ± 1.5% deposition in lower airways, and Anderson Cascade Impactor deposition revealed a mass median aerodynamic diameter of 2.35 ± 1.02 μm for the aerosolized formulation. In vivo efficacy of the developed formulation was analyzed in bleomycin-induced lung fibrosis model in rats after administration by the inhalation route. Lactate dehydrogenase activity, total protein content, and inflammatory cell infiltration in broncho-alveolar lavage fluid were substantially reduced by liposomal naringin. Oxidative stress was minimized as observed from levels of antioxidant enzymes. Masson’s Trichrome staining of lung tissue revealed significant amelioration of histological changes and lesser deposition of collagen. Overall results indicated the therapeutic potential of the developed non-invasive aerosol formulation for the effective management of pulmonary fibrosis.