Preparation and in vitro evaluation of protective effects of Silibinin-loaded polymeric micelles on human hair against UV-B radiation

BACKGROUND

The purpose of this study was to investigate the protective effect of Silibinin-loaded polymeric micelles from human hair against UV-B radiation.

METHODS

Eight formulations with different concentrations of Silibinin, Pluronic F-127, and Labrasol-Labrafil were made by a solvent evaporation method, and the selected formulation was chosen by examining their properties like particle size and loading efficiency. Six groups of human hair, including a group that received the selected formulation, were exposed to UV-B radiation and by calculating its factors such as peak-to-valley roughness, RMS roughness, FTIR, and the amount of protein loss, the protective effect of the selected formulation was judged.

RESULTS

According to the results, the loading efficiency and particle size of the selected formulation were 45.34% and 43.19 nm. The Silibinin release profile had two parts, fast and slow, which were suitable for creating a drug depot on hair. Its zeta potential also confirmed the minimum electrostatic interference between the formulation and hair surface. The zeta potential of selected formulation was -5.9 mv. Examination of AFM images showed that the selected formulation was able to prevent the increase in peak-to-valley roughness and RMS roughness caused by UV-B radiation. RMS roughness after 600 h of UV radiation in Groups 5 and 6 was significantly lower than the negative control group and the amount of this factor did not differ significantly between 0 and 600, so it can be concluded that the selected formulation containing Silibinin and the positive control group was able to prevent the increase of RMS roughness and hair destruction. In other hands, the two positive control groups and the selected formulation containing Silibinin were able to effectively reduce hair protein loss.

CONCLUSION

Silibinin-loaded polymeric micelles were able to effectively protect hair from structural and chemical changes caused by UV-B radiation.

Silibinin solubilization: combined effect of co-solvency and inclusion complex formation

OBJECTIVE

Belonging to the class II drugs according to the biopharmaceutics classification system, silibinin (SLB) benefits from high permeability but suffers poor solubility that negatively affects the development of any delivery system. This research aimed to improve SLB solubility by combined use of co-solvency and complexation phenomena.

METHODS

Solubility studies were performed using the phase solubility analysis according to the shake-flask method in the presence of ethanol and 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) as a co-solvent and inclusion complexing agent, respectively. SLB release studies from chitosan nanoparticles were carried out in double-wall, diffusion cells using the optimized drug release medium.

RESULTS

SLB solubility was mathematically optimized constraining to using the lowest concentrations of ethanol and HP-β-CD. SLB solubility increased linearly with the increase of HP-β-CD concentration. The solubility in PBS-ethanol mixtures followed a log-linear model. SLB solubility in the presence of the ethanol co-solvent and HP-β-CD complexing agent was optimized by adopting a genetic algorithm suggesting the phosphate buffer saline solution supplemented by 6%v/v ethanol and 8 mM HP-β-CD as an optimized medium. The optimized solution was examined to study SLB release from chitosan nanoparticles (4.5 ± 0.2% drug loading) at 37 °C under static conditions. The sigmoidal release profile of SLB from the particles indicated a combination of erosion and diffusion mechanisms governing drug release from the nanoparticles.

CONCLUSION

SLB solubility in a buffered solution supplemented by ethanol co-solvent and HP-β-CD complexing agent is a function of free drug present in the semi-aqueous media, the drug-ligand binary complex, and the drug/ligand/co-solvent ternary complex.

Tackling of Renal Carcinogenesis in Wistar Rats by Silybum marianum Total Extract, Silymarin, and Silibinin via Modulation of Oxidative Stress, Apoptosis, Nrf2, PPARγ, NF-κB, and PI3K/Akt Signaling Pathways

The present work was designed to assess the efficacy of Silybum marianum total extract (STE), silymarin (Sm), and silibinin (Sb) against experimentally induced renal carcinogenesis in male Wistar rats and their roles in regulating oxidative stress, inflammation, apoptosis, and carcinogenesis. The diethylnitrosamine (DEN)/2-acetylaminofluorene (AAF)/carbon tetrachloride (CCl4)-administered rats were orally treated with STE (200 mg/kg b.w.), Sm (150 mg/kg b.w.), and Sb (5 mg/kg b.w.) every other day either from the 1st week or from the 16th week of carcinogen administration to the end of 25th week. The treatments with STE, Sm, and Sb attenuated markers of toxicity in serum, decreased kidney lipid peroxidation (LPO), and significantly reinforced the renal antioxidant armory. The biochemical results were further confirmed by the histopathological alterations. The treatments also led to suppression of proinflammatory mediators such as NF-κβ, p65, Iκβα, and IL-6 in association with inhibition of the PI3K/Akt pathway. Furthermore, they activated the expressions of PPARs, Nrf2, and IL-4 in addition to downregulation of apoptotic proteins p53 and caspase-3 and upregulation of antiapoptotic mediator Bcl-2. The obtained data supply potent proof for the efficacy of STE, Sm, and Sb to counteract renal carcinogenesis via alteration of varied molecular pathways.

Oral Administration of Silibinin Ameliorates Cognitive Deficits of Parkinson's Disease Mouse Model by Restoring Mitochondrial Disorders in Hippocampus

Besides motor disorder, cognitive dysfunction is also common in Parkinson's disease (PD). Essentially no causal therapy for cognitive dysfunction of PD exists at present. In this study, a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of PD was used to analyze the neuroprotective potential of orally administered silibinin, a proverbial hepatoprotective flavonoid derived from the herb milk thistle (Silybum marianum). Results demonstrated that silibinin administration significantly attenuated MPTP-induced cognitive impairment in behavioral tests. Nissl staining results showed that MPTP injection significantly increases the loss of neurons in the hippocampus. However, these mice were protected by oral administration of silibinin, accompanying reduction in the cell apoptosis in the hippocampus. The hippocampal aggregates of α-synuclein (α-syn) appeared in MPTP-injected mice, but were significantly decreased by silibinin treatment. MPTP injection induced oxidative stress, as evidenced by increased malondialdehyde (MDA) and decreased superoxide dismutase (SOD). The oxidative stress was alleviated by silibinin treatment. Mitochondrial disorder including the decline of mitochondrial membrane potential (MMP) was another signature in the hippocampus of MPTP-treated mice, accompanying increased mitochondrial fission and decreased fusion. Silibinin administration restored these mitochondrial disorders, as expected for the protection against MPTP injury. These findings suggest that silibinin has a potential to be further developed as a therapeutic candidate for cognitive dysfunction in PD.

The hepatoprotective effect of silibinin after hepatic ischemia/reperfusion in a rat model is confirmed by immunohistochemistry and qRT-PCR

OBJECTIVES

We investigated the positive effect of silibinin after IV administration as silibinin-hydroxypropyl-β-cyclodextrin lyophilized product, by measuring gene expression and liver tissue protein levels of tumor necrosis factor-α, interleukin-6, monocyte chemoattractant protein-1, matrix metalloproteinases matrix metalloproteinases and tissue inhibitor of matrix metalloproteinases-2.

METHODS

63 Wistar rats of age 13.24±4.40 weeks underwent ischemia/reperfusion (I/R) injury of the liver. The animals were randomized into three groups: Sham (S; n = 7); Control (C; n-28); silibinin (Si; n-28). The C and Si groups underwent 45 min ischemia. Si received silibinin-hydroxypropyl-β-cyclodextrin intravenously immediately before reperfusion at a dose of 5 mg/kg. Both groups were further divided into 4 subgroups, based on euthanasia time (i.e., 60, 120, 180 and 240 min).

KEY FINDINGS

qRT-PCR results confirmed the statistically significant reduction of the expression of the pro-inflammatory factors at 240 min after I/R injury (tumor necrosis factor-α: P < 0.05; MCR1: P < 0.05) and matrix metalloproteinases (matrix metalloproteinases 2: P < 0.05; matrix metalloproteinases 3: P < 0.05) and the increase of tissue inhibitor of matrix metalloproteinases-2 in liver tissue in the Si group. Moreover, results of immunohistochemistry levels confirmed that at 240 min pro-inflammatory factors (tumor necrosis factor-α: P < 0.05; MCR1: P < 0.05) and matrix metalloproteinases ( matrix metalloproteinases 2: P < 0.05; matrix metalloproteinases 3: P < 0.05) had a statistically significantly lower expression in the Si group while tissue inhibitor of matrix metalloproteinases-2 had a higher expression.

CONCLUSIONS

Silibinin may have a beneficial effect on the protection of the liver.

Silibinin-hydroxypropyl-β-cyclodextrin (SLB-HP-β-CD) complex prevents apoptosis in liver and kidney after hepatic ischemia-reperfusion injury

BACKGROUND

We investigated the protective effect of silibinin on rat liver and kidney after hepatic inschemia/reperfusion (I/R) injury.

METHODS AND MATERIALS

Sixty three male Wistar-type rats (median age 13 weeks; average weight 314 g) were subjected to I/R injury of the liver. They were randomly divided into three groups: Sham (n = 7), Control (C, n = 28) and Silibinin (Si, n = 28). The last group received intravenously silibinin. The C and Si groups were each subdivided in four subgroups according to euthanasia times (i.e., 60, 120, 180, 240 min). We assessed expression of caspase-3 and TUNEL assay, and biochemical and histological parameters.

RESULTS

At 240 min, expression of caspase-3 and TUNEL assay were statistically significantly lower in the Si compared to the C group for both liver and kidney. SGOT and SGPT were also statistically significantly lower in the Si than in the C group at all time points. Histological parameters of the liver were also improved in the Si group.

CONCLUSION

Silibinin was found to exhibit a protective effect on liver and kidney after hepatic I/R injury. The present results are encouraging for further studies and future clinical application.

A Simple HPLC Method for the Quantitative Determination of Silybin in Rat Plasma: Application to a Comparative Pharmacokinetic Study on Commercial Silymarin Products

Silybin (SBN) is a major active constituent of silymarin, a mixture of flavonoids found in fruits and seeds of milk thistle. The aim of this study was to describe a simple bioanalytical method for quantifying SBN in rat plasma. A simple protein deproteinization procedure with acetonitrile (ACN) was employed for plasma sample preparation. A reversed column and gradient elution of a mobile phase (mixture of phosphate buffer (pH 5.0) and ACN) were used for chromatographic separation. The selectivity, linearity (50–5000 ng/mL), precision, accuracy, recovery, matrix effect, and stability for this method were validated as per the current Food and Drug Administration (FDA) guidelines. Our method for SBN was applied to a comparative pharmacokinetic study on four different commercial silymarin products. This in vivo rat study demonstrated that product #4 significantly enhanced the relative oral bioavailability of SBN, as compared to product #1–3. Therefore, the bioanalytical method proposed herein could serve as a promising alternative for preclinical pharmacokinetic studies on silymarin products and, by extension, clinical use after partial modification and validation.