Self-assembled nanomicelles of amphiphilic clotrimazole glycyl-glycine analogue augmented drug delivery, apoptosis and restrained melanoma tumour progression

Auranofin-loaded PLGA nanoparticles alleviate cognitive deficit induced by streptozotocin in rats model: modulation of oxidative stress, neuroinflammatory markers, and neurotransmitters

Alzheimer's disease remains an unsolved neurological puzzle with no cure. Current therapies offer only symptomatic relief, hindered by limited uptake through the blood-brain barrier. Auranofin, an FDA-approved compound, exhibits potent antioxidative and anti-inflammatory properties targeting brain disorders. Yet, its oral bioavailability challenge prompts the exploration of nanoformulation-based solutions enhancing blood-brain barrier penetrability. The study aimed to investigate the neuroprotective potential of auranofin nanoparticles in streptozotocin-induced AD rats. Auranofin-containing polylactic-co-glycolic acid nanoparticles were formulated by the multiple emulsion solvent evaporation method. Characterization was done by determining entrapment efficiency, particle size distribution, surface charge, and morphology. An in vivo study was performed by administering streptozotocin (3 mg/kg/i.c.v., days 1 and 3), auranofin (5 and 10 mg/kg), auranofin nanoparticles (2.5 and 5 mg/kg), and donepezil (2 mg/kg) for 14 days orally. Behavioral deficits were evaluated using the open field test, Morris water maze, objective recognition test, change in oxidative stress levels, and AD markers in the brain. Following the decapitation of the rats, the brains were excised to isolate the hippocampus. Subsequent analyses included the quantification of biochemical and neuroinflammatory markers, as well as the assessment of neurotransmitter levels. The characterization of auranofin nanoparticles showed an entrapment efficiency of 98%, an average particle size of 101.5 ± 10.3 nm, a surface charge of 27.5 ± 5.10 mV, and a polydispersity index of 0.438 ± 0.12. In vivo, administration of auranofin and auranofin nanoparticles significantly reversed streptozotocin-induced cognitive deficits, biochemical alteration, neuroinflammatory markers, and neurotransmitter levels. The present finding suggests that auranofin nanoparticles have more significant neuroprotective potential than auranofin alone. The therapeutic efficacy may be attributed to its antioxidant and anti-inflammatory properties, as well as its positive neuromodulatory effects. Therefore, our findings suggest that it could be a promising candidate for Alzheimer's disease therapy.

Dipeptide nanostructures: Synthesis, interactions, advantages and biomedical applications

Short peptides are important in the design of self-assembled materials due to their versatility and flexibility. Self-assembled dipeptides, a group of peptide nanostructures, have highly attractive uses in the field of biomedicine. Recently these materials have proved to be important nanostructures because of their biocompatibility, low-cost and simplicity of synthesis, functionality/easy tunability and nano dimensions. Although there are different studies on peptide and protein-based nanostructures, more information about self-assembled nanostructures for dipeptides is still required to discover the advantages, challenges, importance, synthesis, interactions, and applications. This review describes and discusses the self-assembled dipeptide nanostructures especially for biomedical applications.

Fatty acid chain length impacts nanonizing capacity of albumin-fatty acid nanomicelles: Enhanced physicochemical property and cellular delivery of poorly water-soluble drug

This study aimed to design the ideal nanonizing vehicle for poorly water-soluble model curcumin (CCM) using fattigation-platform nanotechnology, and to investigate the effects of fatty acid salts chain length on nanonizing CCM and its efficient delivery to different cancer cells. HSA-fatty acid conjugates were synthesized by EDC/NHS coupling. Fattigation-platform nanomicelles (NMs), prepared by film hydration, exhibited uniform and spherical morphology, although, each NM varied in particle size, zeta potential, and critical micelle concentration according to the types of fatty acid. Preliminary solubility studies of albumin conjugates with 5 types of fatty acid salts of different chain lengths revealed that C14 exhibited the highest solubilization of CCM. CCM-loaded HSA-C14 NMs demonstrated the highest drug content (5.35 ± 0.48%) and loading efficiency (95.93 ± 1.87%) compared to other NMs. It exhibited enhanced drug release rate and reduced micelle size in biorelevant dissolution medium. Interestingly, this solubilization approach was well applied in poorly water-soluble docetaxel trihydrate (DTX). Preliminary solubility results of DTX was also corresponded to the stable nanonization phenomenon in biorelevant dissolution medium. Compared to the CCM EtOH solution, HSA-C14 NMs showed higher internalization in cancer cell lines A549 and MCF-7, and consequently, exhibited significantly increased cytotoxicity against both cell lines. Therefore, this study provides a new solubilization approach for poorly water-soluble drugs using fatty acid salts of different chain lengths and their micellar formations via nanonization, which could be a promising tool for targeted cancer therapy using poorly water-soluble drugs.

Folate-grafted glycyl-glycine-melphalan conjugate self-assembled amphilphilc nanomicelles augmented drug delivery, cytotoxicity and cellular uptake in human ovarian cancer cells

Objectives: Folic acid was coupled to melphalan using glycyl-glycine (FA-Gly-Gly-Melphalan) to synthesize self-assembled nanomicelles for targeting ovarian cancer cells, SKOV3.Methods and Results: FA-Gly-Gly-Melphalan self-assembled nanomicelles were prepared with critical micellar concentration (CMC) of 12-μg/ml. The mean particle size of FA-Gly-Gly-Melphalan self-assembled nanomicelles was measured to be 95.9 ± 3.4-nm significantly (P < 0.05) higher than 73.8 ± 6.3-nm of Gly-Gly-Melphalan self-assembled nanomicelles. Subsequently, zeta-potential of FA-Gly-Gly-Melphalan self-assembled nanomicelles was estimated to be -28.0 ± 1.5-mV significantly (P < 0.05) lower than -36.6 ± 2.7-mV of Gly-Gly-Melphalan self-assembled nanomicelles. The IC₅₀ of FA-Gly-Gly-Melphalan self-assembled nanomicelles was estimated to be 4.1-μg/ml significantly (P < 0.001) lower than 14.2-μg/ml of Gly-Gly-Melphalan self-assembled nanomicelles and >18-μg/ml of melphalan. FA-Gly-Gly-Melphalan self-assembled nanomicelles preferentially accumulated in cytoplasm of SKOV3 cells nearby nucleus via receptor mediated endocytosis pathway after 24-h of incubation period, whilst Gly-Gly-Melphalan self-assembled nanomicelles were not incorporated sufficiently.Conclusion: FA-Gly-Gly-Melphalan self-assembled nanomicelles warrant in depth in vivo study for their safety, efficacy, and potency in clinical settings.

Biological Evaluation of Noscapine analogues as Potent and Microtubule-Targeted Anticancer Agents

In present investigation, an attempt was undertaken to modify the C-9 position of noscapine (Nos), an opium alkaloid to yield 9 -hydroxy methyl and 9 -carbaldehyde oxime analogues for augmenting anticancer potential. The synthesis of 9-hydroxy methyl analogue of Nos was carried out by Blanc reaction and 9-carbaldehyde oxime was engineered by oxime formation method and characterized using FT-IR, ¹H NMR, ¹³C NMR, mass spectroscopy, and so on techniques. In silico docking techniques informed that 9-hydroxy methyl and 9-carbaldehyde oxime analogues of Nos had higher binding energy score as compared to Nos. The IC50 of Nos was estimated to be 46.8 µM signficantly (P < 0.05) higher than 8.2 µM of 9-carbaldehyde oxime and 4.6 µM of 9-hydroxy methyl analogue of Nos in U87, human glioblastoma cells. Moreover, there was significant (P < 0.05) difference between the IC50 of 9-carbaldehyde oxime and 9-hydroxy methyl analogue of Nos. Consistent to in vitro cytotoxicity data, 9-hydroxy methyl analogue of Nos induced significantly (P < 0.05) higher degree of apoptosis of 84.6% in U87 cells as compared to 78.5% and 64.3% demonstrated by 9-carbaldehyde oxime and Nos, respectively. Thus the higher therapeutic efficacy of 9-hydroxy methyl analogue of Nos may be credited to higher solubility and inhibitory constant (K).

Comparative Gene Expression Analysis in WM164 Melanoma Cells Revealed That β-β-Dimethylacrylshikonin Leads to ROS Generation, Loss of Mitochondrial Membrane Potential, and Autophagy Induction

Skin cancer is currently diagnosed as one in every three cancers. Melanoma, the most aggressive form of skin cancer, is responsible for 79% of skin cancer deaths and the incidence is rising faster than in any other solid tumor type. Previously, we have demonstrated that dimethylacrylshikonin (DMAS), isolated from the roots of Onosma paniculata (Boraginaceae), exhibited the lowest IC₅₀ values against different tumor types out of several isolated shikonin derivatives. DMAS was especially cytotoxic towards melanoma cells and led to apoptosis and cell cycle arrest. In this study, we performed a comprehensive gene expression study to investigate the mechanism of action in more detail. Gene expression signature was compared to vehicle-treated WM164 control cells after 24 h of DMAS treatment; where 1192 distinct mRNAs could be identified as expressed in all replicates and 89 were at least 2-fold differentially expressed. DMAS favored catabolic processes and led in particular to p62 increase which is involved in cell growth, survival, and autophagy. More in-depth experiments revealed that DMAS led to autophagy, ROS generation, and loss of mitochondrial membrane potential in different melanoma cells. It has been reported that the induction of an autophagic cell death represents a highly effective approach in melanoma therapy.

Synthesis of Novel Shikonin Derivatives and Pharmacological Effects of Cyclopropylacetylshikonin on Melanoma Cells

Despite much research in the last centuries, treatment of malignant melanoma is still challenging because of its mostly unnoticeable metastatic spreading and aggressive growth rate. Therefore, the discovery of novel drug leads is an important goal. In a previous study, we have isolated several shikonin derivatives from the roots of Onosma paniculata Bureau & Franchet (Boraginaceae) which evolved as promising anticancer candidates. β,β-Dimethylacrylshikonin (1) was the most cytotoxic derivative and exhibited strong tumor growth inhibitory activity, in particular, towards melanoma cells. In this study, we synthesized eighteen novel shikonin derivatives in order to obtain compounds which exhibit a higher cytotoxicity than 1. We investigated their cytotoxic potential against various melanoma cell lines and juvenile skin fibroblasts. The most active compound was (R)-1-(1,4-dihydro-5,8-dihydroxy-1,4-dioxonaphthalen-2-yl)-4-methylpent-3-enyl cyclopropylacetate (cyclopropylacetylshikonin) (6). It revealed significant stronger tumor growth inhibitory activity towards two melanoma cell lines derived from metastatic lesions (WM164 and MUG-Mel2). Further investigations have shown that 6 induced apoptosis caspase-dependently, increased the protein levels of cleaved PARP, and led to double-stranded DNA breaks as shown by phosphorylation of H2AX. Cell membrane damage and cell cycle arrest were not observed.