Formulation Strategies for Enhancing the Bioavailability of Silymarin: The State of the Art

Synthesis, characterization and hepatoprotective effect of silymarin phytosome nanoparticles on ethanol-induced hepatotoxicity in rats

Introduction

Silymarin proved to be a beneficial herbal medicine against many hepatic disorders such as alcoholic liver disease (ALD). However, its application is restricted due to its low bioavailability and consequently decreased efficacy. We herein used a nano-based approach known as "phytosome", to improve silymarin bioavailability and increase its efficacy.

Methods

Phytosome nanoparticles (NPs) were synthesized using thin film hydration method. NPs size, electrical charge, morphology, stability, molecular interaction, entrapment efficiency (EE %) and loading capacity (LC %) were determined. Moreover, in vitro toxicity of NPs was investigated on mesenchymal stem cells (MSCs) viability using MTT assay. In vivo experiments were performed using 24 adult rats that were divided into four groups including control, ethanol (EtOH) treatment, silymarin/EtOH treatment and silymarin phytosome/EtOH, with 6 mice in each group. Experimental groups were given 40% EtOH, silymarin (50 mg/kg) and silymarin phytosome (200 mg/kg) through the gastric gavage once a day for 3 weeks. Biochemical parameters, containing ALP, ALT, AST, GGT, GPx and MDA were measured before and after experiment to investigate the protective effect of silymarin and its phytosomal form. And histopathological examination was done to evaluate pathological changes.

Results

Silymarin phytosome NPs with the mean size of 100 nm were produced and were well tolerated in cell culture. These NPs showed a considerable protective effect against ALD through inverting the biochemical parameters (ALP, ALT, AST, GGT, GPx) and histopathological alterations.

Conclusion

Silymarin phytosomal NPs can be used as an efficient treatment for ALD.

Regulation of Gut Microflora by Lactobacillus casei Zhang Attenuates Liver Injury in Mice Caused by Anti-Tuberculosis Drugs

The gut-liver axis may provide a new perspective for treating anti-tuberculosis drug-induced liver injury (ATDILI). Herein, the protective effect of Lactobacillus casei (Lc) was investigated by modulating gut microflora (GM) and the toll like receptor 4 (TLR4)-nuclear factor (NF)-κB-myeloiddifferentiationfactor 88 (MyD88) pathway. C57BL/6J mice were given three levels of Lc intragastrically for 2 h before administering isoniazid and rifampicin for 8 weeks. Blood, liver, and colon tissues, as well as cecal contents, were collected for biochemical and histological examination, as well as Western blot, quantitative real time polymerase chain reaction (qRT-PCR), and 16S rRNA analyses. Lc intervention decreased alkaline phosphatase (ALP), superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA), and tumor necrosis factor (TNF)-α levels (p < 0.05), recovered hepatic lobules, and reduced hepatocyte necrosis to alleviate liver injury induced by anti-tuberculosis drugs. Moreover, Lc also increased the abundance of Lactobacillus and Desulfovibrio and decreased Bilophila abundance, while enhancing zona occludens (ZO)-1 and claudin-1 protein expression compared with the model group (p < 0.05). Furthermore, Lc pretreatment reduced the lipopolysaccharide (LPS) level and downregulated NF-κB and MyD88 protein expression (p < 0.05), thus restraining pathway activation. Spearman correlation analysis indicated that Lactobacillus and Desulfovibrio were positively correlated with ZO-1 or occludin protein expression and negatively correlated with pathway protein expression. Desulfovibrio had significant negative relationships with alanine aminotransferase (ALT) and LPS levels. In contrast, Bilophila had negative associations with ZO-1, occludin, and claudin-1 protein expressions and positive correlations with LPS and pathway proteins. The results prove that Lactobacillus casei can enhance the intestinal barrier and change the composition of the gut microflora. Moreover, Lactobacillus casei may also inhibit TLR4-NF-κB-MyD88 pathway activation and alleviate ATDILI.

Pharmaceutical prospects of Silymarin for the treatment of neurological patients: an updated insight

Background

Silymarin is a polyphenolic flavonoid complex extricated from dried fruits and seeds of the plant Silybum marianum L. Chemically, it is a mixture of flavonolignan complexes consisting of silybin, isosilybin, silychristin, silydianin, a minor quantity of taxifolin, and other polyphenolic compounds, which possess different bio medicinal values.

Purpose

This review critically looks into the current status, pharmaceutical prospects and limitations of the clinical application of Silymarin for treating neurological disorders. In particular, Silymarin's medicinal properties and molecular mechanisms are focused on providing a better-compiled understanding helpful in its neuro-pharmacological or therapeutic aspects.

Methods

This review was compiled by the literature search done using three databases, i.e., PubMed (Medline), EMBASE and Science Direct, up to January 2023, using the keywords-Silymarin, neurological disorders, cognitive disorders, Type 2 Diabetes, pharmaceutical prospects and treatment. Then, potentially relevant publications and studies (matching the eligible criteria) were retrieved and selected to explain in this review using PRISMA 2020 (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) study flow chart.

Result

Since its discovery, it has been widely studied as a hepatoprotective drug for various liver disorders. However, in the last 10-15 years, several research studies have shown its putative neuroprotective nature against various brain disorders, including psychiatric, neurodegenerative, cognitive, metabolic and other neurological disorders. The main underlying neuroprotective mechanisms in preventing and curing such disorders are the antioxidant, anti-inflammatory, anti-apoptotic, pro-neurotrophic and pro-estrogenic nature of the bioactive molecules.

Conclusion

This review provides a lucid summary of the well-studied neuroprotective effects of Silymarin, its underlying molecular mechanisms and current limitations for its usage during neurological disorders. Finally, we have suggested a future course of action for developing it as a novel herbal drug for the treatment of brain diseases.

A systematic review of the protective effects of silymarin/silibinin against doxorubicin-induced cardiotoxicity

PURPOSE

Although doxorubicin chemotherapy is commonly applied for treating different malignant tumors, cardiotoxicity induced by this chemotherapeutic agent restricts its clinical use. The use of silymarin/silibinin may mitigate the doxorubicin-induced cardiac adverse effects. For this aim, the potential cardioprotective effects of silymarin/silibinin against the doxorubicin-induced cardiotoxicity were systematically reviewed.

METHODS

In this study, we performed a systematic search in accordance with PRISMA guideline for identifying all relevant studies on "the role of silymarin/silibinin against doxorubicin-induced cardiotoxicity" in different electronic databases up to June 2022. Sixty-one articles were obtained and screened based on the predefined inclusion and exclusion criteria. Thirteen eligible papers were finally included in this review.

RESULTS

According to the echocardiographic and electrocardiographic findings, the doxorubicin-treated groups presented a significant reduction in ejection fraction, tissue Doppler peak mitral annulus systolic velocity, and fractional shortening as well as bradycardia, prolongation of QT and QRS interval. However, these echocardiographic abnormalities were obviously improved in the silymarin plus doxorubicin groups. As well, the doxorubicin administration led to induce histopathological and biochemical changes in the cardiac cells/tissue; in contrast, the silymarin/silibinin co-administration could mitigate these induced alterations (for most of the cases).

CONCLUSION

According to the findings, it was found that the co-administration of silymarin/silibinin alleviates the doxorubicin-induced cardiac adverse effects. Silymarin/silibinin exerts its cardioprotective effects via antioxidant, anti-inflammatory, anti-apoptotic activities, and other mechanisms.

Use of Milk Thistle in Farm and Companion Animals: A Review

Milk thistle, Silybum marianum, is a medicinal plant grown for its bioactive compounds with well-documented antioxidant and hepatoprotective properties. Milk thistle has a well-established pharmacological reputation for treatments of human liver disease, but it is also used in animals. This review summarizes the experimental evidence of milk thistle's effects on animals when administered as silymarin extract (feed additive) or a feed ingredient, if administered as seed or expeller/cake with the seed residue still containing the bioactive components. The use as a feed additive or feed ingredient is motivated by the complexity of silymarin registration as a veterinary drug. In farm animals, the drug improves the animals' performance and product quality and oxidative stability, supports liver function during the productive life-cycle, improves gut-health and morphology, and can reduce intestinal pathogens. In dogs and cats, the treatment is focused on acute and chronic liver diseases including the detoxification processes and support of drug treatments including chemotherapy. In equine athletes, milk seed cake showed positive effects and a faster return of cortisol to the resting values before exercise occurred. In aquaculture, it confirms its usefulness in supporting animal health and performance. In certain studies it is not clear what has been administered, and the composition and doses are not always clearly reported. A few studies reported no effects, but none reported problems connected to milk thistle administration. However, the overall picture shows that the use of milk thistle results in improved or restored health parameters or better animal performance.

Silymarin in combination with ATRA enhances apoptosis induction in human acute promyelocytic NB4 cells

Although all-trans retinoic acid (ATRA) is an efficient pattern in acute promyelocytic leukemia (APL) therapy, further studies are required due to the extant clinical limitations of ATRA. It has been reported that Silymarin, an anti-cancer herbal substance extracted from milk thistle (Silybum marianum), is able to regulate apoptosis in various types of cancer cells through different mechanisms of action. This study investigated the apoptosis-inducing effect of Silymarin (SM) alone and in combination with ATRA on human acute promyelocytic NB4 cells. Examination using MTT assay indicated that SM treatment leads to growth inhibition in NB4 cells in a dose-dependent manner. The IC50 values of SM and ATRA were calculated 90 μM and 2 μM, respectively. Cell cycle analysis by flow cytometry revealed that a more increase in the sub-G1 phase (a sign of apoptosis) when cells were exposed to SM in combination with ATRA. The incidence of apoptosis was confirmed through Hoechst 33258 staining and Annexin V-FITC analysis. The results showed that Silymarin enhances ATRA-induced apoptosis. The flow cytometric analysis also indicated an enhancement in levels of ROS in the treated cells with both compounds. The real-time PCR illustrated that SM targets apoptosis by down-regulation in Survivin and Bcl-2 while up-regulation in Bax. The findings showed that the combination of the two compounds is more effective in the induction of apoptosis in NB4 cells. Molecular docking studies indicated that Sylibin, as a primary compound of the SM, binds to the BH3 domain of Bcl-2 and the BIR domain of Survivin with various affinities. Based on the findings, it seems that SM used alone and in combination with ATRA may be beneficial for inducing apoptosis in APL cells.

Enhancement of in-vitro anti-oral cancer activities of silymarin using dispersion of nanostructured lipid carrier in mucoadhesive in-situ gel

Silymarin (SME) shows multiple therapeutic actions against several cancers, however, low aqueous solubility and poor bioavailability issues restrict its clinical use. In this study, SME was loaded in nanostructured lipid carriers (NLCs) and further incorporated in mucoadhesive in-situ gel (SME-NLCs-Plx/CP-ISG) for localized treatment of oral cancer. Using a 3³ Box-Behnken design (BBD), an optimized SME-NLC formula was developed with the ratios of solid lipids, surfactant concentration, and sonication time as independent variables, while particle size (PS), polydispersity index (PDI), and % encapsulation efficiency (EE) as dependent variables, resulting in 315.5 ± 0.1 nm PS, 0.341 ± 0.01 PDI, and 71.05 ± 0.05 % EE. Structural studies confirmed the formation of SME-NLCs. SME-NLCs incorporated in-situ gel demonstrated a sustained release for SME, indicating enhanced retention on the buccal mucosal membrane. The in-situ gel containing SME-NLCs showed a marked decrease in IC₅₀ value (24.90 ± 0.45 µM) than SME-NLCs (28.40 ± 0.89 µM) and plain SME (36.60 ± 0.26 µM). The studies demonstrated that Reactive oxygen species (ROS) generation potential and SME-NLCs-Plx/CP-ISG induced apoptosis at Sub-G0 phase owing to higher penetration of SME-NLCs led to higher inhibition against human KB oral cancer cells. Therefore, SME-NLCs-Plx/CP-ISG can be the alternative to chemotherapy and surgery with site-specific delivery of SME to oral cancer patients.

Bio-Actives from Natural Products with Potential Cardioprotective Properties: Isolation, Identification, and Pharmacological Actions of Apigenin, Quercetin, and Silibinin

Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality worldwide. As a result, pharmaceutical and non-pharmaceutical interventions modifying risk factors for CVDs are a top priority of scientific research. Non-pharmaceutical therapeutical approaches, including herbal supplements, have gained growing interest from researchers as part of the therapeutic strategies for primary or secondary prevention of CVDs. Several experimental studies have supported the potential effects of apigenin, quercetin, and silibinin as beneficial supplements in cohorts at risk of CVDs. Accordingly, this comprehensive review focused critically on the cardioprotective effects/mechanisms of the abovementioned three bio-active compounds from natural products. For this purpose, we have included in vitro, preclinical, and clinical studies associated with atherosclerosis and a wide variety of cardiovascular risk factors (hypertension, diabetes, dyslipidemia, obesity, cardiac injury, and metabolic syndrome). In addition, we attempted to summarize and categorize the laboratory methods for their isolation and identification from plant extracts. This review unveiled many uncertainties which are still unexplored, such as the extrapolation of experimental results to clinical practice, mainly due to the small clinical studies, heterogeneous doses, divergent constituents, and the absence of pharmacodynamic/pharmacokinetic analyses.

Formulation Strategies for Enhancing Pharmaceutical and Nutraceutical Potential of Sesamol: A Natural Phenolic Bioactive

Natural plants and their products continue to be the major source of phytoconstituents in food and therapeutics. Scientific studies have evidenced the benefits of sesame oil and its bioactives in various health conditions. Various bioactives present in it include sesamin, sasamolin, sesaminol, and sesamol; among these, sesamol represents a major constituent. This bioactive is responsible for preventing various diseases including cancer, hepatic disorders, cardiac ailments, and neurological diseases. In the last decade, the application of sesamol in the management of various disorders has attracted the increasing interest of the research community. Owing to its prominent pharmacological activities, such as antioxidant, antiinflammatory, antineoplastic, and antimicrobial, sesamol has been explored for the above-mentioned disorders. However, despite the above-mentioned therapeutic potential, its clinical utility is mainly hindered owing to low solubility, stability, bioavailability, and rapid clearance issues. In this regard, numerous strategies have been explored to surpass these restrictions with the formulation of novel carrier platforms. This review aims to describe the various reports and summarize the different pharmacological activities of sesamol. Furthermore, one part of this review is devoted to formulating strategies to improve sesamol's challenges. To resolve the issues such as the stability, low bioavailability, and high systemic clearance of sesamol, novel carrier systems have been developed to open a new avenue to utilize this bioactive as an efficient first-line treatment for various diseases.

Silymarin Encapsulated Liposomal Formulation: An Effective Treatment Modality against Copper Toxicity Associated Liver Dysfunction and Neurobehavioral Abnormalities in Wistar Rats

Wilson's disease causes copper accumulation in the liver and extrahepatic organs. The available therapies aim to lower copper levels by various means. However, a potent drug that can repair the damaged liver and brain tissue is needed. Silymarin has hepatoprotective, antioxidant, and cytoprotective properties. However, poor oral bioavailability reduces its efficacy. In this study, a "thin film hydration method" was used for synthesizing silymarin-encapsulated liposome nanoparticles (SLNPs) and evaluated them against copper toxicity, associated liver dysfunction and neurobehavioral abnormalities in Wistar rats. After copper toxicity induction, serological and behavioral assays were conducted to evaluate treatment approaches. Histological examination of the diseased rats revealed severe hepatocyte necrosis and neuronal vacuolation. These cellular degenerations were mild in rats treated with SLNPs and a combination of zinc and SLNPs (ZSLNPs). SLNPs also decreased liver enzymes and enhanced rats' spatial memory significantly (p = 0.006) in the diseased rats. During forced swim tests, SLNPs treated rats exhibited a 60-s reduction in the immobility period, indicating reduced depression. ZSLNPs were significantly more effective than traditional zinc therapy in decreasing the immobility period (p = 0.0008) and reducing liver enzymes, but not in improving spatial memory. Overall, SLNPs enhanced oral silymarin administration and managed copper toxicity symptoms.

Synthesized nanoliposome-encapsulated kaempferol attenuates liver health parameters and gene expression in mice challenged by cadmium-induced toxicity

In the present research, we encapsulated a flavonoid called kaempferol into nanoliposomal structures and the health-promoting effects of synthesized nanoliposome-loaded kaempferol (NLK) were evaluated in mice challenged by cadmium-induced . The NLK characteristics, such as size, zeta potential, and polydispersity index, were 218.4 nm, -28.55 mV, and 0.29, respectively. The in vivo experiment revealed that the mice receiving water containing cadmium (2 mg/kg body weight/day) showed significant (p < 0.05) weight loss, an increase in liver enzyme activities, and hepatic oxidative stress. Dietary supplementation with NLK at concentrations of 2.5 and 5 mg/kg mice body weight notably (p < 0.05) improved the body weight, liver enzyme activities, hepatic oxidative stress, and antioxidant potential of the liver. Our findings elucidated that NLK could alleviate the toxicity of cadmium in mice challenged by cadmium-induced toxicity.

Silymarin as a preventive or therapeutic measure for chemotherapy and radiotherapy-induced adverse reactions: a comprehensive review of preclinical and clinical data

PURPOSE

Thus far, silymarin has been examined in several studies for prevention or treatment of various chemotherapy or radiotherapy-induced adverse reactions. In this review, we try to collect all available human, animal, and pre-clinical data in this field.

METHODS

The search was done in Scopus, PubMed, Medline, and systematic reviews in the Cochrane database, using the following keywords: "Cancer," "Chemotherapy," "Radiotherapy," "Mucositis," "Nephrotoxicity," "Dermatitis," "Ototoxicity," "Cardiotoxicity," "Nephrotoxicity," "Hepatotoxicity," "Reproductive system," "Silybum marianum," "Milk thistle," and "Silymarin" and "Silybin." We included all relevant in vitro, in vivo, and human studies up to the date of publication.

RESULTS

Based on 64 included studies in this review, silymarin is considered a safe and well-tolerated compound, with no known clinical drug interaction. Notably, multiple adverse reactions of chemotherapeutic agents are effectively managed by its antioxidant, anti-apoptotic, anti-inflammatory, and anti-immunomodulatory properties. Clinical trials suggest that oral silymarin may be a promising adjuvant with cancer treatments, particularly against hepatotoxicity (n = 10), nephrotoxicity (n = 3), diarrhea (n = 1), and mucositis (n = 3), whereas its topical formulation can be particularly effective against radiodermatitis (n = 2) and hand-foot syndrome (HFS) (n = 1).

CONCLUSION

Further studies are required to determine the optimal dose, duration, and the best formulation of silymarin to prevent and/or manage chemotherapy and radiotherapy-induced complications.

Self-Nanoemulsifying Drug Delivery System for Enhanced Bioavailability of Madecassic Acid: In vitro and in vivo Evaluation

Purpose

Madecassic acid (MCA) is a natural triterpenoid isolated from centellae herba that has diverse biological effects, such as anti-inflammatory, antioxidant, and anticancer activities. However, the efficacy of MCA is limited by low oral bioavailability caused by its extremely poor aqueous solubility. This study aimed to develop a self-nanoemulsifying drug delivery system (SNEDDS) for MCA to improve its oral absorption.

Methods

The utilized oil phases, surfactants, and co-surfactants for SNEDDS were selected based on the solubility of MCA and emulsification efficiency. The optimized formulation was characterized for pharmaceutical properties and its pharmacokinetic behavior was examined in rats. Besides, the intestinal absorption property of MCA was investigated using in situ single-pass intestinal perfusion and intestinal lymphatic transport.

Results

The optimized nanoemulsion formula consists of Capryol 90:Labrasol:Kolliphor ELP:Transcutol HP in a weight ratio of 1:2.7:2.7:3.6 (w/w/w/w). MCA-loaded SNEDDS presented a small droplet size (21.52 ± 0.23 nm), with a zeta potential value of -3.05 ± 0.3 mV. Compared with pure MCA, SNEDDS had a higher effective permeability coefficient and showed 8.47-fold and 4.01-fold of maximum plasma concentration (C_max) and area under the plasma concentration-time curve (AUC), respectively. Cycloheximide was pretreated before the experiment to evaluate the degree of lymphatic uptake. The results showed that cycloheximide greatly influenced the absorption of SNEDDS, resulting in 82.26% and 76.98% reduction in C_max and AUC, respectively.

Conclusion

This study reports the MCA-loaded SNEDDS with distinctly enhanced in vitro and in vivo performance compared with pure MCA and concludes that the SNEDDS formulation could be a viable and effective strategy for improving the dissolution rate and bioavailability of poor aqueous-soluble ingredients.

Co-Treatments of Gardeniae Fructus and Silymarin Ameliorates Excessive Oxidative Stress-Driven Liver Fibrosis by Regulation of Hepatic Sirtuin1 Activities Using Thioacetamide-Induced Mice Model

Gardeniae Fructus (GF, the dried ripe fruits of Gardenia jasminoides Ellis) has traditionally been used to treat various diseases in East Asian countries, such as liver disease. Silymarin is a well-known medicine used to treat numerous liver diseases globally. The present study was purposed to evaluate the synergistic effects of GF and silymarin on the thioacetamide (TAA)-induced liver fibrosis of a mouse model. Mice were orally administered with distilled water, GF (100 mg/kg, GF 100), silymarin (100 mg/kg, Sily 100), and GF and silymarin mixtures (50 and 100 mg/kg, GS 50 and 100). The GS group showed remarkable amelioration of liver injury in the serum levels and histopathology by observing the inflamed cell infiltrations and decreases in necrotic bodies through the liver tissue. TAA caused liver tissue oxidation, which was evidenced by the abnormal statuses of lipid peroxidation and deteriorations in the total glutathione in the hepatic protein levels; moreover, the immunohistochemistry supported the increases in the positive signals against 4-hydroxyneal and 8-OHdG through the liver tissue. These alterations corresponded well to hepatic inflammation by an increase in F4/80 positive cells and increases in pro-inflammatory cytokines in the hepatic protein levels; however, administration with GS, especially the high dose group, not only remarkably reduced oxidative stress and DNA damage in the liver cells but also considerably diminished pro-inflammatory cytokines, which were driven by Kupffer cell activations, as compared with each of the single treatment groups. The pharmacological properties of GS prolonged liver fibrosis by the amelioration of hepatic stellate cells’ (HSCs’) activation that is dominantly expressed by huge extracellular matrix (ECM) molecules including α-smooth muscle actin, and collagen type1 and 3, respectively. We further figured out that GS ameliorated HSCs activated by the regulation of Sirtuin 1 (Sirt1) activities in the hepatic protein levels, and this finding excellently reenacted the transforming growth factor-β-treated LX-2-cells-induced cell death signals depending on the Sirt1 activities. Future studies need to reveal the pharmacological roles of GS on the specific cell types during the liver fibrosis condition.

Silymarin-Functionalized Selenium Nanoparticles Prevent LPS-Induced Inflammatory Response in RAW264.7 Cells through Downregulation of the PI3K/Akt/NF-κB Pathway

Silymarin exhibits an anti-inflammatory property in various cancers and inflammatory diseases. In our previous work, silymarin-mediated selenium nanoparticles (SeNPs) (Si-SeNPs) were developed using a green synthesis technique, and its potential as an anticancer agent was confirmed. In order to further examine the extended comprehensive potential of Si-SeNPs, this investigation focuses on studying the enhanced anti-inflammatory effect of Si-SeNPs in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Enzyme-linked immunosorbent assay and quantitative reverse transcription-polymerase chain reaction were used to evaluate the expression of pro-inflammatory mediators and cytokines. Western blotting and immunofluorescence assays were conducted to assess the protein expression of p-PI3K, p-Akt, p-NF-κB, and p-IκBα. Compared to silymarin, Si-SeNPs exhibited a significantly increased inhibitory effect on LPS-induced release of nitric oxide and the expression of pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α) and interleukin 1β (IL-1β) in RAW264.7 cells. A western blot assay indicated that Si-SeNPs downregulated the PI3K/Akt and NF-κB signaling pathways. The immunofluorescence assay suggested that Si-SeNPs inhibited the nuclear translocation and the activation of NF-κB. In addition, 740 Y-P (PI3K agonist) was used to demonstrate that activating the PI3K/Akt signal could partially reverse the inflammatory response, suggesting a causal role of the PI3K/Akt signaling pathway in the anti-inflammatory effect of Si-SeNPs. Consequently, these findings indicate that Si-SeNPs could be a functional agent of the attenuation of LPS-induced inflammatory responses in RAW264.7 macrophages through inhibiting the PI3K/Akt/NF-κB signaling pathway. In addition, biosynthesized Si-SeNPs could be more effective at reducing inflammation than only silymarin extracts. Thus, this study lays an experimental foundation for the clinical application of using biosynthesized SeNPs as a novel candidate in the field of inflammation-associated diseases.

The new antioxidant 1-benzoyl-6-hydroxy-2,2,4-trimethyl-1,2-dihydroquinoline has a protective effect against carbon tetrachloride-induced hepatic injury in rats

Liver diseases with the central pathogenetic mechanism of oxidative stress are one of the main causes of mortality worldwide. Therefore, dihydroquinoline derivatives, which are precursors of hepatoprotectors and have antioxidant activity, are of interest. We have previously found that some compounds in this class have the ability to normalize redox homeostasis under experimental conditions. Here, we initially analyzed the hepatoprotective potential of the dihydroquinoline derivative 1-benzoyl-6-hydroxy-2,2,4-trimethyl-1,2-dihydroquinoline (BHDQ) for carbon tetrachloride (CCl ₄)-induced liver injury in rats. Results suggested that BHDQ normalized the alanine aminotransferase, aspartate aminotransferase, and gamma-glutamyl transpeptidase in serum. We also observed an improvement in liver tissue morphology related to BHDQ. Animals with CCl ₄-induced liver injuries treated with BHDQ had less oxidative stress compared to animals with CCl ₄-induced liver injury. BHDQ promoted activation changes in superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione transferase on control values in animals with CCl ₄-induced liver injury. BHDQ also activated gene transcription in Sod1 and Gpx1 via nuclear factor erythroid 2-related factor 2 and forkhead box protein O1 factors. Therefore, the compound of concern has a hepatoprotective effect by inhibiting the development of necrotic processes in the liver tissue, through antioxidation.

Drug Delivery Systems and Flavonoids: Current Knowledge in Melanoma Treatment and Future Perspectives

Melanoma is an aggressive form of skin cancer with a high prevalence in the population. An early diagnosis is crucial to cure this disease. Still, when this is not possible, combining potent pharmacological agents and effective drug delivery systems is essential to achieve optimal treatment and improve patients' quality of life. Nanotechnology application in biomedical sciences to encapsulate anticancer drugs, including flavonoids, in order to enhance therapeutic efficacy has attracted particular interest. Flavonoids have shown effectiveness against various types of cancers including in melanoma, but they show low aqueous solubility, low stability and very poor oral bioavailability. The utilization of novel drug delivery systems could increase flavonoid bioavailability, thereby potentiating its antitumor effects in melanoma. This review summarizes the potential of different flavonoids in melanoma treatment and the several nanosystems used to improve their biological activity, considering published information that reported improved biological and pharmacological properties of encapsulated flavonoids.

A randomized trial assessing the efficacy of Silymarin on endometrioma-related manifestations

To study the effect of silymarin on the Interleukin-6 (IL-6) level, size of endometrioma lesion, pain, sexual function, and Quality of Life (QoL) in women diagnosed with endometriosis. This randomized, double-blind placebo-controlled clinical trial was performed on 70 women with endometriosis which was divided into two groups of intervention and control. The intervention was 140 mg silymarin (or matching placebo) administered twice daily for 12 weeks. The volume of endometrioma lesions, the level of IL-6 concentration in serum, pain, sexual function, and QoL were analyzed before and after the intervention. The means of endometrioma volume (P = 0.04), IL-6 (P = 0.002), and pain (P < 0.001) were reduced significantly in the silymarin group after intervention. However, the QoL and female sexual function did not improve substantially in the two groups (P > 0.05). Silymarin significantly reduced interleukin-6 levels, sizes of endometrioma lesions, and pain-related symptoms. The trial has been registered in the Iranian Registry of Clinical Trials (IRCT20150905023897N5) on 4th February 2020 (04/02/2020) ( https://en.irct.ir/trial/42215 ) and the date of initial participant enrollment was 2nd March 2020 (02/03/2020).

Silibinin: a toxicologist's herbal medicine?

Silymarin is an herbal remedy, commonly called milk thistle, or St. Mary's Thistle, and has been used for over 2000 years. It has been available as a capsule of the plant extract in Europe since 1974 to treat hepatic disorders. To date toxicologists have relied on animal studies, human case series, or retrospective reviews to decide on its use. In the U.S. the ability to use IV silibinin, its pharmacologically active purified flavonolignan, is hindered by its lack of availability as a Food and Drug Administration approved pharmaceutical preparation. This commentary reviews the in vitro studies, animal studies, and human retrospective analyses which form the basis for its clinical use. Despite the numerous publications, summarized in this issue in a systematic review, the mortality rate from Amanita mushroom ingestion remains stubbornly the same over four decades of use, and hovers around 10%. Although in the retrospective systematic review the use of silibinin, or penicillin, compared to routine care is statistically significantly superior when the primary outcome is fatality. Despite this there is no quality randomized trial to definitively demonstrate its utility. While, intravenous silibinin has a low toxicity, unanswered is whether it is useful in protecting the liver in cases of amanitin-containing mushrooms toxicity, and whether earlier administration would likely improve outcomes.

Enhanced bioavailability and hepatoprotective effect of silymarin by preparing silymarin-loaded solid dispersion formulation using freeze-drying method

This study aimed to develop a solid dispersion formulation of silymarin (Silymarin-SD) using freeze-drying method to enhance its oral bioavailability (BA) by inhibiting the intestinal first-pass effect and increasing its solubility and permeability. Silymarin-SD formulation (i.e., silymarin:tween 80:hydroxypropyl cellulose (HPC) = 1:1:3 (w/w/w) significantly increased silymarin permeability in the duodenum, jejunum, and ileum by decreasing the efflux ratio of silymarin and by inhibiting silymarin-glucuronidation activity, in which tween 80 played a crucial role. As a result, orally administered Silymarin-SD formulation increased plasma silymarin concentrations and decreased silymarin-glucuronide in rats compared with silymarin alone and silymmarin:D-α-tocopherol polyethylene glycol 1000 succinate (1:1, w/w) formulation. In addition to modulating intestinal first-pass effect, Silymarin-SD formulation showed a significantly higher cumulative dissolution for 120 min compared with that of silymarin from the physical mixture (PM) of the same composition as Silymarin-SD and silymarin alone; the relative BA of silymarin-SD increased to 215% and 589% compared with silymarin-PM and silymarin alone, respectively. This could be attributed to the amorphous status of the Silymarin-SD formulation without chemical interaction with excipients, such as tween 80 and HPC. Moreover, the hepatoprotective effect of Silymarin-SD in acetaminophen-induced acute hepatotoxicity, as estimated from the alanine aminotransferase and aspartate aminotransferase values, was superior to that of silymarin. In conclusion, the increase in the dissolution rate and intestinal permeability of silymarin, and the inhibition of silymarin-glucuronidation by the Silymarin-SD formulation, prepared using tween 80 and HPC, increased its plasma concentration and resulted in a superior hepatoprotective effect compared to silymarin.

Silymarin nanocrystals-laden chondroitin sulphate-based thermoreversible hydrogels; A promising approach for bioavailability enhancement

Hydrogels has gained tremendous interest as a controlled release drug delivery. However, currently it is a big challenge to attain high drug-loading as well as stable and sustained release of hydrophobic drugs. The poor aqueous solubility and low bioavailability of many drugs have driven the need for research in new formulations. This manuscript hypothesized that incorporation of nanocrystals of hydrophobic drug, such as silymarin into thermoreversible hydrogel could be a solution to these problems. Herein, we prepared nanocrystals of silymarin by antisolvent precipitation technique and characterized for morphology, particle size, polydispersity index (PDI) and zeta potential. Moreover, physical cross-linking of hydrogel formulations based on chondroitin sulphate (CS), kappa-Carrageenan (κ-Cr) and Pluronic® F127 was confirmed by Fourier transformed infrared spectroscopy (FT-IR). The hydrogel gelation time and temperature of optimized hydrogel was 14 ± 3.2 s and 34 ± 0.6 °C, respectively. The release data revealed controlled release of silymarin up to 48 h and in-vivo pharmacokinetic profiling was done in rabbits and further analyzed by high-performance liquid chromatography (HPLC). It is believed that the nanocrystals loaded thermoreversible injectable hydrogel system fabricated in this study provides high drug loading as well as controlled and stable release of hydrophobic drug for extended period.

Evaluation of the efficacy of oral nano-silymarin formulation in hospitalized patients with COVID-19: A double-blind placebo-controlled clinical trial

Considering the outbreak pandemic of Coronavirus Disease 2019 (COVID-19), the lack of effective therapeutic strategies for the management of this viral disease, and the increasing evidence on the antiviral potential of silymarin, this study aimed to investigate the effectiveness of silymarin nanomicelles on the symptom's resolution time, laboratory parameters, and liver enzymes in patients with COVID-19. The participants were assigned to the nano-silymarin (n = 25) (receiving SinaLive soft gel, containing 70 mg silymarin as nanomicelles) or placebo groups (n = 25) three times daily for two weeks. Patients' symptoms and laboratory findings were assessed at baseline and during the follow-up period (one week and one month after the beginning of the treatment). No significant differences were observed between the two groups in terms of symptoms resolution time, laboratory parameters, and hospitalization duration (p > 0.05). However, the alanine aminotransferase level decreased significantly in the treatment group, compared to the placebo group (p < 0.001). Concomitant use of dexamethasone and remdesivir with silymarin might make the effects of silymarin on the improvement of patients' condition unclear. Further clinical trials are recommended with diverse dosages and larger sample sizes.

Phytosomes as a Plausible Nano-Delivery System for Enhanced Oral Bioavailability and Improved Hepatoprotective Activity of Silymarin

Silymarin, a phyto-constituent derived from the plant Silybum marianum, has been widely acknowledged for its hepatoprotective activities. Nevertheless, its clinical utility is adversely hampered by its poor water-solubility and its limited oral bioavailability. The aim of this study was to investigate the efficacy of phospholipid-based phytosomes for enhancing the oral bioavailability of silymarin. The phytosomes were prepared using the solvent evaporation technique and were optimized using a full factorial design. The optimized silymarin phytosomal formulation was then characterized for particle size, surface morphology, aqueous solubility, and in vitro drug release. Furthermore, in vivo antioxidant activity, hepatoprotective activity and oral bioavailability of the optimized formula were investigated in a rat model. The prepared silymarin phytosomes were discrete particles with a porous, nearly smooth surface and were 218.4 ± 2.54 nm in diameter. In addition, the optimized silymarin phytosomal formulation showed a significant improvement in aqueous solubility (~360 µg/mL) compared to pure silymarin and manifested a higher rate and extent of silymarin release from the optimized formula in dissolution studies. The in vivo assessment studies revealed that the optimized silymarin phytosomal formulation efficiently exerted a hepatoprotective effect in a CCl₄-induced hepatotoxicity rat model via restoring the normal levels of antioxidant enzymes and ameliorating cellular abnormalities caused by CCl₄-intoxication. Most notably, as compared to pure silymarin, the optimized silymarin phytosomal formulation significantly improved silymarin oral bioavailability, as indicated by a 6-fold increase in the systemic bioavailability. Collectively, phytosomes might represent a plausible phospholipid-based nanocarrier for improving the oral bioavailability of phyto-constituents with poor aqueous solubility.

Comparative efficacy of silibinin and nano-silibinin on lead poisoning in Male Wistar rats

Lead (Pb) is an environmental neurotoxin that can lead to toxicity. It has shown that tissues can be exposed to oxidative stress in lead poisoning. Since silymarin is a natural agent with antioxidant effects, this study aimed to investigate the antioxidant and chelation effects of silibinin and nano-silibinin on the oxidative stress status in lead-poisoned rats. Sixty male Wistar rats randomly divided into ten groups (n = 6). Control and Pb groups treated with or without silibinin and nano-silibinin for six days. Following measuring of weight and blood lead levels, biochemical antioxidant parameters evaluated. Finally, a histopathological examination of the liver performed. In this experiment, silibinin and more efficiently nano-silibinin prevented weight loss and blood lead level elevation induced by lead. Also, they increased the attenuated levels of superoxide dismutase (SOD) activity, catalase (CAT), total thiol molecules (TTM), glutathione (GSH), and total antioxidant capacity (TAC). Lead-induced elevation of lipid peroxidation products (MDA) and nitric oxide (NO) normalized to the standard level in silibinin and especially nano-silibinin groups. These data suggested that silibinin and especially nano-silibinin can decrease blood lead levels and prevent weight loss and oxidative stress in the lead-poisoned rat's model.

Silibinin Schiff Base Derivatives Counteract CCl4-Induced Acute Liver Injury by Enhancing Anti-Inflammatory and Antiapoptotic Bioactivities

Background

Purpose

Patients and Methods

Results

Conclusion

Nanocarriers for Drug Delivery: An Overview with Emphasis on Vitamin D and K Transportation

Mounting evidence shows that supplementation with vitamin D and K or their analogs induces beneficial effects in various diseases, e.g., osteoarticular, cardiovascular, or carcinogenesis. The use of drugs delivery systems via organic and inorganic nanocarriers increases the bioavailability of vitamins and analogs, enhancing their cellular delivery and effects. The nanotechnology-based dietary supplements and drugs produced by the food and pharmaceutical industries overcome the issues associated with vitamin administration, such as stability, absorption or low bioavailability. Consequently, there is a continuous interest in optimizing the carriers' systems in order to make them more efficient and specific for the targeted tissue. In this pioneer review, we try to circumscribe the most relevant aspects related to nanocarriers for drug delivery, compare different types of nanoparticles for vitamin D and K transportation, and critically address their benefits and disadvantages.

Nanoparticles as phytochemical carriers for cancer treatment: News of the last decade

INTRODUCTION

The development and application of novel therapeutic medicines for the treatment of cancer are of vital importance to improve the disease's outcome and survival rate. One noteworthy treatment approach is the use of biologically active compounds present in natural products. Even though these phytocompounds present anti-inflammatory, antioxidant, and anticancer properties, their use is limited essentially due to poor systemic delivery, low bioavailability, and water solubility concerns. To make full use of the anticancer potential of natural products, these limitations need to be technologically addressed. In this sense, nanotechnology emerges as a promising drug delivery system strategy.

AREAS COVERED

In this review, the benefits and potential of nanodelivery systems for natural products encapsulation as promising therapeutic approaches for cancer, which were developed during the last decade, are highlighted.

EXPERT OPINION

The nanotechnology area has been under extensive research in the medical field given its capacity for improving the therapeutic potential of drugs by increasing their bioavailability and allowing a targeted delivery to the tumor site. Thereby, the nanoencapsulation of phytocompounds can have a direct impact on the recognized therapeutic activity of natural products towards cancer.

Biological Activities, Pharmacokinetics and Toxicity of Nootkatone: A Review

Abstract:

Plant-based drugs have a significant impact on modern therapeutics due to their vast array of pharmacological activities. The integration of herbal plants in the current healthcare system has emerged as a new field of research. It can be used for the identification of novel lead compound candidates for future drug development. Nootkatone is a sesquiterpene derivative and an isolate of grapefruit. Shreds of evidence illustrate that nootkatone targets few molecular mechanisms to exhibit its pharmacological activity and yet needs more exploration to be established. The current review is related to nootkatone, drafted through a literature search using research articles and books from different sources, including Science Direct, Google Scholar, Elsevier, PubMed, and Scopus. It has been reported to possess a wide range of pharmacological activities such as anti-inflammatory, anticancer, antibacterial, hepatoprotective, neuroprotective, and cardioprotective. Although preclinical studies in experimental animal models suggest that nootkatone has therapeutic potential, it is further warranted to evaluate its toxicity and pharmacokinetic parameters before being applied to humans. Hence in the present review, we have summarized the scientific knowledge on nootkatone with a particular emphasis on its pharmacological properties to encourage researchers for further exploration in preclinical and clinical settings.

Hydroxypropyl-β-cyclodextrin Enhances Oral Absorption of Silymarin Nanoparticles Prepared Using PureNano™ Continuous Crystallizer

The oral bioavailability of drugs is limited by factors such as poor membrane permeability, low solubility, and low dissolution rate. Silymarin (SLM) is a health-food active ingredient that is good for immunosuppression and tumor suppression. However, obtaining a good oral bioavailability is difficult owing to its poor solubility and low dissolution ability. To overcome these concerns, we previously prepared SLM nanoparticles (NPs) using the high-pressure crystallization method (PureNano^TM) and freeze-dried them with erythritol (Ery) or hydroxypropyl-β-CyD (HP-β-CyD) as a water-soluble dispersion stabilizer. In the present study, we investigated the mechanism underlying the improved absorption of SLM/hypromellose (HPMC)/HP-β-CyD NPs after oral administration. The SLM/HPMC nano-suspension prepared using PureNano^TM exhibited a narrow size distribution. The size of the SLM/HPMC/HP-β-CyD NPs was approximately 250 nm after hydration. The SLM/HPMC/HP-β-CyD NPs were rapidly dissolved, and demonstrated a high solubility under supersaturated conditions. Additionally, they exhibited good wettability and their membrane permeability was improved compared with that of SLM original powder. These results suggest that the formulation of SLM NPs using PureNano^TM and freeze-drying with HP-β-CyD improves the absorption of SLM after oral administration by enhancing solubility, wettability, and membrane permeability.

Silymarin is an ally against insulin resistance: A review

Silymarin is obtained from the Milk thistle plant Silybum marianum and has been used over the centuries to treat principally liver disease, although it has also been studied for its beneficial effects in cardioprotection, neuroprotection, immune modulation, and cancer among others. Importantly, silymarin's active component silybin is a flavonolignan that exhibits different activities such as; scavenger, anti-oxidant, anti-inflammatory, and recently revealed, insulin-sensitizing properties which have been explored in clinical trials in patients with insulin resistance. In this review, we summarize the most relevant research of silymarin's effect on lipid and carbohydrate metabolism, focusing the attention on insulin resistance, which is well known to play a crucial role in metabolic disease progression.

A comprehensive review on phytochemicals for fatty liver: are they potential adjuvants?

Non-alcoholic fatty liver disease (NAFLD) is considered the hepatic manifestation of metabolic syndrome and, as such, is associated with obesity. With the current and growing epidemic of obesity, NAFLD is already considered the most common liver disease in the world. Currently, there is no official treatment for the disease besides weight loss. Although there are a few synthetic drugs currently being studied, there is also an abundance of herbal products that could also be used for treatment. With the World Health Organization (WHO) traditional medicine strategy (2014-2023) in mind, this review aims to analyze the mechanisms of action of some of these herbal products, as well as evaluate toxicity and herb-drug interactions available in literature.

Role of Silymarin in Cancer Treatment: Facts, Hypotheses, and Questions

The flavonoid silymarin extracted from the seeds of Sylibum marianum is a mixture of 6 flavolignan isomers. The 3 more important isomers are silybin (or silibinin), silydianin, and silychristin. Silybin is functionally the most active of these compounds. This group of flavonoids has been extensively studied and they have been used as hepato-protective substances for the mushroom Amanita phalloides intoxication and mainly chronic liver diseases such as alcoholic cirrhosis and nonalcoholic fatty liver. Hepatitis C progression is not, or slightly, modified by silymarin. Recently, it has also been proposed for SARS COVID-19 infection therapy. The biochemical and molecular mechanisms of action of these substances in cancer are subjects of ongoing research. Paradoxically, many of its identified actions such as antioxidant, promoter of ribosomal synthesis, and mitochondrial membrane stabilization, may seem protumoral at first sight, however, silymarin compounds have clear anticancer effects. Some of them are: decreasing migration through multiple targeting, decreasing hypoxia inducible factor-1α expression, inducing apoptosis in some malignant cells, and inhibiting promitotic signaling among others. Interestingly, the antitumoral activity of silymarin compounds is limited to malignant cells while the nonmalignant cells seem not to be affected. Furthermore, there is a long history of silymarin use in human diseases without toxicity after prolonged administration. The ample distribution and easy accessibility to milk thistle-the source of silymarin compounds, its over the counter availability, the fact that it is a weed, some controversial issues regarding bioavailability, and being a nutraceutical rather than a drug, has somehow led medical professionals to view its anticancer effects with skepticism. This is a fundamental reason why it never achieved bedside status in cancer treatment. However, in spite of all the antitumoral effects, silymarin actually has dual effects and in some cases such as pancreatic cancer it can promote stemness. This review deals with recent investigations to elucidate the molecular actions of this flavonoid in cancer, and to consider the possibility of repurposing it. Particular attention is dedicated to silymarin's dual role in cancer and to some controversies of its real effectiveness.

In silico formulation prediction of drug/cyclodextrin/polymer ternary complexes by machine learning and molecular modeling techniques

Ternary cyclodextrin (CD) complexes (drug/CD/polymer) can effectively improve the solubility of water-insoluble drugs with large size than binary CD formulations. However, ternary formulations are screened by a trial-and-error approach, which is laborious and material-wasting. Current research aims to develop a prediction model for ternary CD formulations by combined machine learning and molecular modeling. 596 ternary formulations data were collected to build a prediction model by machine learning. The random forest model achieved good performance with R² = 0.887 in S_T prediction and R² = 0.815 in S_T/S_B prediction. Two ternary formulations (Hydrocortisone/β-CD/HPMC and dovitinib/γ-CD/CMC) were used to validate the prediction model. Molecular modeling results showed that HPMC not only warped around hydrocortisone but also prevented CD molecules from self-aggregation to increase solubility. In conclusion, a prediction model for the ternary CD formulations was successfully developed, which will significantly accelerate the formulation screening process to benefit the formulation development of water-insoluble drugs.

A Customized Screening Tool Approach for the Development of a Self-Nanoemulsifying Drug Delivery System (SNEDDS)

The present study focused on establishing a novel, (pre-)screening approach that enables the development of promising performing self-nanoemulsifying drug delivery systems (SNEDDSs) with a limited number of experiments. The strategic approach was based on first identifying appropriate excipients (oils/lipids, surfactants, and co-solvents) providing a high saturation solubility for lipophilic model compounds with poor aqueous solubility. Excipients meeting these requirements were selected for SNEDDS development, and a special triangular mixture design was applied for determining excipient ratios for the SNEDDS formulations. Celecoxib and fenofibrate were used as model drugs. Formulations were studied applying a specific combination of in vitro characterization methods. Specifications for a promising SNEDDS formulation were self-imposed: a very small droplet size (< 50 nm), a narrow size distribution of these droplets (PDI < 0.15) and a high transmittance following SNEDDS dispersion in water (> 99% in comparison with purified water). Excipients that provided a nanoemulsion after dispersion were combined, and ratios were optimized using a customized mapping method in a triangular mixture design. The best performing formulations were finally studied for their in vitro release performance. Results of the study demonstrate the efficiency of the customized screening tool approach. Since it enables successful SNEDDS development in a short time with manageable resources, this novel screening tool approach could play an important role in future SNEDDS development.

PEG-Modified tert-Octylcalix[8]arenes as Drug Delivery Nanocarriers of Silibinin

The hepatoprotective properties of silibinin, as well its therapeutic potential as an anticancer and chemo-preventive agent, have failed to progress towards clinical development and commercialization due to this material's unfavorable pharmacokinetics and physicochemical properties, low aqueous solubility, and chemical instability. The present contribution is focused on the feasibility of using PEGylated calixarene, in particular polyoxyethylene-derivatized tert-octylcalix[8]arene, to prepare various platforms for the delivery of silibinin, such as inclusion complexes and supramolecular aggregates thereof. The inclusion complex is characterized by various instrumental methods. At concentrations exceeding the critical micellization concentration of PEGylated calixarene, the tremendous solubility increment of silibinin is attributed to the additional solubilization and hydrophobic non-covalent interactions of the drug with supramolecular aggregates. PEG-modified tert-octylcalix[8]arenes, used as drug delivery carriers for silibinin, were additionally investigated for cytotoxicity against human tumor cell lines.

Recent Advancement in Chitosan-Based Nanoparticles for Improved Oral Bioavailability and Bioactivity of Phytochemicals: Challenges and Perspectives

The excellent therapeutic potential of a variety of phytochemicals in different diseases has been proven by extensive studies throughout history. However, most phytochemicals are characterized by a high molecular weight, poor aqueous solubility, limited gastrointestinal permeability, extensive pre-systemic metabolism, and poor stability in the harsh gastrointestinal milieu. Therefore, loading of these phytochemicals in biodegradable and biocompatible nanoparticles (NPs) might be an effective approach to improve their bioactivity. Different nanocarrier systems have been developed in recent decades to deliver phytochemicals. Among them, NPs based on chitosan (CS) (CS-NPs), a mucoadhesive, non-toxic, and biodegradable polysaccharide, are considered the best nanoplatform for the oral delivery of phytochemicals. This review highlights the oral delivery of natural products, i.e., phytochemicals, encapsulated in NPs prepared from a natural polymer, i.e., CS, for improved bioavailability and bioactivity. The unique properties of CS for oral delivery such as its mucoadhesiveness, non-toxicity, excellent stability in the harsh environment of the GIT, good solubility in slightly acidic and alkaline conditions, and ability to enhance intestinal permeability are discussed first, and then the outcomes of various phytochemical-loaded CS-NPs after oral administration are discussed in detail. Furthermore, different challenges associated with the oral delivery of phytochemicals with CS-NPs and future directions are also discussed.

Cold-Active Lipase-Based Biocatalysts for Silymarin Valorization through Biocatalytic Acylation of Silybin

Extremophilic biocatalysts represent an enhanced solution in various industrial applications. Integrating enzymes with high catalytic potential at low temperatures into production schemes such as cold-pressed silymarin processing not only brings value to the silymarin recovery from biomass residues, but also improves its solubility properties for biocatalytic modification. Therefore, a cold-active lipase-mediated biocatalytic system has been developed for silybin acylation with methyl fatty acid esters based on the extracellular protein fractions produced by the psychrophilic bacterial strain Psychrobacter SC65A.3 isolated from Scarisoara Ice Cave (Romania). The extracellular production of the lipase fraction was enhanced by 1% olive-oil-enriched culture media. Through multiple immobilization approaches of the cold-active putative lipases (using carbodiimide, aldehyde-hydrazine, or glutaraldehyde coupling), bio-composites (S1–5) with similar or even higher catalytic activity under cold-active conditions (25 °C) have been synthesized by covalent attachment to nano-/micro-sized magnetic or polymeric resin beads. Characterization methods (e.g., FTIR DRIFT, SEM, enzyme activity) strengthen the biocatalysts’ settlement and potential. Thus, the developed immobilized biocatalysts exhibited between 80 and 128% recovery of the catalytic activity for protein loading in the range 90–99% and this led to an immobilization yield up to 89%. The biocatalytic acylation performance reached a maximum of 67% silybin conversion with methyl decanoate acylating agent and nano-support immobilized lipase biocatalyst.

The Emerging Role of Nanomedicine in the Management of Nonalcoholic Fatty Liver Disease: A State-of-the-Art Review

Nonalcoholic fatty liver disease (NAFLD) is a common chronic liver disease that can lead to end-stage liver disease needing a liver transplant. Many pharmacological approaches are used to reduce the disease progression in NAFLD. However, current strategies remain ineffective to reverse the progression of NAFLD completely. Employing nanoparticles as a drug delivery system has demonstrated significant potential for improving the bioavailability of drugs in the treatment of NAFLD. Various types of nanoparticles are exploited in this regard for the management of NAFLD. In this review, we cover the current therapeutic approaches to manage NAFLD and provide a review of recent up-to-date advances in the uses of nanoparticles for the treatment of NAFLD.

Phytochemicals and Their Possible Mechanisms in Managing COVID-19 and Diabetes

For the writing of this manuscript, we searched information published from 2000 to 2021, through PubMed, Web of Science, Springer, and Science Direct. Focusing on the effects related to respiratory diseases, in addition to possible direct effects towards SARS-CoV-2, coupled with diabetes. Diabetes is a metabolic disease that is characterized by affecting the function of glucose, in addition to insulin insufficiency. This leads to patients with such pathologies as being at greater risk for developing multiple complications and increase exposure to viruses infections. This is the case of severe acute respiratory disease coronavirus 19 (SARS-CoV-2), which gave rise to coronavirus disease 2019 (COVID-19), declared an international public health emergency in March of 2020 Currently, several strategies have been applied in order to prevent the majority of the consequences of COVID-19, especially in patients with chronic diseases such as diabetes. Among the possible treatment options, we found that the use of phytochemical compounds has exhibited beneficial effects for the prevention and inhibition of infection by SARS-CoV-2, as well as for the improvement of the manifestations of diabetes.

Enhanced Bioavailability of AC1497, a Novel Anticancer Drug Candidate, via a Self-Nanoemulsifying Drug Delivery System

AC1497 is an effective dual inhibitor of malate dehydrogenase 1 and 2 targeting cancer metabolism. However, its poor aqueous solubility results in low bioavailability, limiting its clinical development. This study was conducted to develop an effective self-nanoemulsifying drug delivery system (SNEDDS) of AC1497 to improve its oral absorption. Based on the solubility of AC1497 in various oils, surfactants, and cosurfactants, Capryol 90, Kolliphor RH40, and Transcutol HP were selected as the components of SNEDDS. After testing various weight ratios of Capryol 90 (20–30%), Kolliphor RH40 (35–70%), and Transcutol HP (10–35%), SNEDDS-F4 containing 20% Capryol 90, 45% Kolliphor RH40, and 35% Transcutol HP was identified as an optimal SNEDDS with a narrow size distribution (17.8 ± 0.36 nm) and high encapsulation efficiency (93.6 ± 2.28%). Drug release from SNEDDS-F4 was rapid, with approximately 80% of AC1497 release in 10 min while the dissolution of the drug powder was minimal (<2%). Furthermore, SNEDDS-F4 significantly improved the oral absorption of AC1497 in rats. The maximum plasma concentration and area under the plasma concentration–time curve of AC1497 were, respectively 6.82- and 3.14-fold higher for SNEDDS-F4 than for the drug powder. In conclusion, SNEDDS-F4 with Capryol 90, Kolliphor RH40, and Transcutol HP (20:45:35, w/w) effectively improves the solubility and oral absorption of AC1497.

Nanoformulations of Ursolic Acid: A Modern Natural Anticancer Molecule

Background: Ursolic acid (UA) is a natural pentacyclic triterpene derived from fruit, herb, and other plants. UA can act on molecular targets of various signaling pathways, inhibit the growth of cancer cells, promote cycle stagnation, and induce apoptosis, thereby exerting anticancer activity. However, its poor water-solubility, low intestinal mucosal absorption, and low bioavailability restrict its clinical application. In order to overcome these deficiencies, nanotechnology, has been applied to the pharmacological study of UA.

Objective: In this review, we focused on the absorption, distribution, and elimination pharmacokinetics of UA in vivo, as well as on the research progress in various UA nanoformulations, in the hope of providing reference information for the research on the anticancer activity of UA.

Methods: Relevant research articles on Pubmed and Web of Science in recent years were searched selectively by using the keywords and subheadings, and were summarized systematically.

Key finding: The improvement of the antitumor ability of the UA nanoformulations is mainly due to the improvement of the bioavailability and the enhancement of the targeting ability of the UA molecules. UA nanoformulations can even be combined with computational imaging technology for monitoring or diagnosis.

Conclusion: Currently, a variety of UA nanoformulations, such as micelles, liposomes, and nanoparticles, which can increase the solubility and bioactivity of UA, while promoting the accumulation of UA in tumor tissues, have been prepared. Although the research of UA in the nanofield has made great progress, there is still a long way to go before the clinical application of UA nanoformulations.

Systematic review of pharmacokinetics and potential pharmacokinetic interactions of flavonolignans from silymarin

Silymarin is an extract from the seeds (fruits) of Silybum marianum that contains flavonolignans and flavonoids. Although it is frequently used as a hepatoprotective agent, its application remains somewhat debatable, in particular, due to the low oral bioavailability of flavonolignans. Moreover, there are claims of its potential interactions with concomitantly used drugs. This review aims at a systematic summary and critical assessment of known information on the pharmacokinetics of particular silymarin flavonolignans. There are two known major reasons for poor systemic oral bioavailability of flavonolignans: (1) rapid conjugation in intestinal cells or the liver and (2) efflux of parent flavonolignans or formed conjugates back to the lumen of the gastrointestinal tract by intestinal cells and rapid excretion by the liver into the bile. The metabolism of phase I appears to play a minor role, in contrast to extensive conjugation and indeed the unconjugated flavonolignans reach low plasma levels after common doses. Only about 1%-5% of the administered dose is eliminated by the kidneys. Many in vitro studies tested the inhibitory potential of silymarin and its components toward different enzymes and transporters involved in the absorption, metabolism, and excretion of xenobiotics. In most cases, effective concentrations are too high to be relevant under real biological conditions. Most human studies showed no silymarin-drug interactions explainable by these suggested interferences. More interactions were found in animal studies, likely due to the much higher doses administered.