Identification and characterization of β-sitosterol target proteins

Synthesis of a Side Chain Alkyne Analogue of Sitosterol as a Chemical Probe for Imaging in Plant Cells

Clickable chemical tools are essential for studying the localization and role of biomolecules in living cells. For this purpose, alkyne-based close analogs of the respective biomolecules are of outstanding interest. Here, in the field of phytosterols, we present the first alkyne derivative of sitosterol, which fulfills the crucial requirements for such a chemical tool as follows: very similar in size and lipophilicity to the plant phytosterols, and correct absolute configuration at C-24. The alkyne sitosterol FB-DJ-1 was synthesized, starting from stigmasterol, which comprised nine steps, utilizing a novel alkyne activation method, a Johnson-Claisen rearrangement for the stereoselective construction of a branched sterol side chain, and a Bestmann-Ohira reaction for the generation of the alkyne moiety.

The use of beta-sitosterol for the treatment of prostate cancer and benign prostatic hyperplasia

Herbal supplements are widely used to enhance prostate health. These supplements may contain several types of plant sterols, vitamins, and minerals. By weight, however, plant sterols make up an abundant ingredient component, with saw palmetto extract or its primary component, beta-sitosterol, often comprising the most abundant sterol. Saw palmetto extract/beta-sitosterol has been shown to promote anti-tumorigenic processes in prostate cancer cells and rodent models of prostate cancer. It has also been shown to inhibit the 5α-reductase enzyme, thereby behaving similarly to finasteride and dutasteride, which are widely used to treat prostatic enlargement, or benign prostatic hyperplasia (BPH). The aim of this study is to critically examine in vitro, in vivo, and human clinical studies to assess the safety and clinical utility of herbal supplements containing saw palmetto extract/beta-sitosterol for prostate health. The results of this study suggest multiple mechanisms through which beta-sitosterol represses prostate cancer in vitro and in vivo, particularly through its pro-apoptotic effect on prostate epithelial cells. Multiple studies also show that beta-sitosterol significantly improves lower urinary tract symptoms (LUTS) associated with BPH, but to an extent that is generally less effective than that achieved by pharmaceutical grade alpha-adrenergic receptor antagonists or 5α-reductase inhibitors. This latter finding suggests that supplements containing beta-sitosterol might be most appropriate for younger men with minimal LUTS who don't wish to embark on a clinical drug regimen for BPH treatment.

β-Sitosterol as a Promising Anticancer Agent for Chemoprevention and Chemotherapy: Mechanisms of Action and Future Prospects

Cancer is one of the primary causes of death worldwide, and its incidence continues to increase yearly. Despite significant advances in research, the search for effective and nontoxic preventive and therapeutic agents remains greatly important. Cancer is a multimodal disease, where various mechanisms play significant roles in its occurrence and progression. This highlights the need for multitargeted approaches that are not only safe and inexpensive but also provide effective alternatives for current therapeutic regimens. β-Sitosterol (SIT), the most abundant phytosterol found in various plant foods, represents such an option. Preclinical evidence over the past few decades has overwhelmingly shown that SIT exhibits multiple anticancer activities against varied cancers, such as liver, cervical, colon, stomach, breast, lung, pancreatic, and prostate cancers, in addition to leukemia, multiple myeloma, melanoma, and fibrosarcoma. In this article, we present the latest advances and perspectives on SIT-systematically summarizing its antitumor mechanisms of action into 7 main sections and combining current challenges and prospects-for its use as a promising agent for cancer prevention and treatment. In particular, SIT plays a role in cancer prevention and treatment mainly by enhancing apoptosis, inducing cell cycle arrest, bidirectionally regulating oxidative stress, improving metabolic reprogramming, inhibiting invasion and metastasis, modulating immunity and inflammation, and combating drug resistance. Although SIT holds such great promise, the poor aqueous solubility and bioavailability coupled with low targeting efficacy limit its therapeutic efficacy and clinical application. Further research on novel drug delivery systems may improve these deficiencies. Overall, through complex and pleiotropic mechanisms, SIT has good potential for tumor chemoprevention and chemotherapy. However, no clinical trials have yet proven this potential. This review provides theoretical basis and rationality for the further design and conduct of clinical trials to confirm the anticancer activity of SIT.

Assessing the Mechanism of Action of “Fructus Ligustri Lucidi-Cuscutae Semen” in Prostate Cancer Treatment Using Network Pharmacology and Molecular Docking

Objective

To explore the mechanism of action of “Fructus Ligustri Lucidi-Cuscutae Semen” in the treatment of prostate cancer using network pharmacology and molecular docking.

Methods

The active ingredients and targets of “Fructus Ligustri Lucidi-Cuscutae Semen” were obtained by searching the TCMSP and DrugBank databases. These were matched and corrected using the UniProt platform. A drug “active ingredient-target” network map was constructed using Cytoscape 3.8.0. Prostate cancer-related targets were acquired from GeneCards, Disgenet, DrugBank, and other databases. The protein-protein interaction (PPI) network between the drug and prostate cancer was constructed with BioGenet; the crossover network of the two targets was extracted derive the key targets of “Fructus Ligustri Lucidi-Cuscutae Semen” for prostate cancer treatment. We used the Metascape platform for GO and KEGG enrichment analysis of the key targets. AutoDockTools1.5.6 and PyMOL software were used to perform molecular docking.

Results

We obtained 13 active ingredients, 221 drug targets, 1511 prostate cancer targets (including 221 key targets), and 305 KEGG pathways from “Fructus Ligustri Lucidi-Cuscutae Semen.” Paclitaxel, quercetin, kaempferol, TP53, β-sitosterol, EGFR, and ESR1 in “Fructus Ligustri Lucidi-Cuscutae Semen” showed good docking activity.

Conclusion

“Fructus Ligustri Lucidi-Cuscutae Semen” is a valuable clinical guide for the treatment of prostate cancer with multicomponent, multitarget, and multipathway characteristics.

Beta-Sitosterol Modulates the Migration of Vascular Smooth Muscle Cells via the PPARG/AMPK/mTOR Pathway

INTRODUCTION

The increased migration of vascular smooth muscle cells (VSMCs) is an essential pathological factor in the early development of atherosclerosis. Beta-sitosterol (BS), a natural phytosterol abundant in plant seeds, exhibits various bioactivities, including cardioprotective effects. However, its effects on VSMC migration and underlying mechanisms remain to be explored.

METHOD AND RESULT

BS inhibited the proliferation and migration of angiotensin II-induced A7r5 cells and reduced intracellular oxidative stress. Targets related to VSMC migration and the targets of BS were screened, cross-referenced, and analyzed by network pharmacology combined with molecular docking technology. The identified targets were verified at the protein and gene levels using Western blotting and quantitative PCR, respectively. BS was observed to activate peroxisome proliferator-activated receptor-γ (PPARG) and adenosine 5'-monophosphate-activated protein kinase (AMPK) and negatively regulate mammalian target of rapamycin (mTOR) expression. Furthermore, a PPARG inhibitor reversed the BS-induced activation of AMPK and mTOR.

CONCLUSION

This study indicated that regulation of the PPARG/AMPK/mTOR signaling pathway could potentially contribute to the inhibitory effects of BS on angiotensin II-induced VSMC migration.

The Search for Putative Hits in Combating Leishmaniasis: The Contributions of Natural Products Over the Last Decade

Despite advancements in the areas of omics and chemoinformatics, potent novel biotherapeutic molecules with new modes of actions are needed for leishmaniasis. The socioeconomic burden of leishmaniasis remains alarming in endemic regions. Currently, reports from existing endemic areas such as Nepal, Iran, Brazil, India, Sudan and Afghanistan, as well as newly affected countries such as Peru, Bolivia and Somalia indicate concerns of chemoresistance to the classical antimonial treatment. As a result, effective antileishmanial agents which are safe and affordable are urgently needed. Natural products from both flora and fauna have contributed immensely to chemotherapeutics and serve as vital sources of new chemical agents. This review focuses on a systematic cross-sectional view of all characterized anti-leishmanial compounds from natural sources over the last decade. Furthermore, IC50/EC50, cytotoxicity and suggested mechanisms of action of some of these natural products are provided. The natural product classification includes alkaloids, terpenes, terpenoids, and phenolics. The plethora of reported mechanisms involve calcium channel inhibition, immunomodulation and apoptosis. Making available enriched data pertaining to bioactivity and mechanisms of natural products complement current efforts geared towards unraveling potent leishmanicides of therapeutic relevance.

The protective effects of β-sitosterol and vermicularin from Thamnolia vermicularis (Sw.) Ach. against skin aging in vitro

Aged skin, featured with dryness and wrinkles, has received mounting attention due to its adverse influences on beauty. β-Sitosterol and vermicularin are two common active ingredients of Thamnolia vermicularis (Sw.) Ach., a traditional Chinese medicine, of which the anti-aging effect has been discovered. Their protective performance against skin aging was assayed by co-culturing with skin cells in this work. Results showed that β-sitosterol promoted the biosynthesis of hyaluronic acid by increasing the expression of hyaluronic acid synthases in fibroblasts and enhanced the expression of skin barrier functional proteins including aquaporin 3, loricrin, filaggrin and involucrin in keratinocytes, which conduced to the moisture retention within skin. Moreover, vermicularin might function as an anti-wrinkle agent by preventing the loss of collagen type I. Specifically, vermicularin reduced the amount of reactive oxygen species within hydrogen-peroxide-induced fibroblasts; together with suppressing the activation of mitogen-activated protein kinases, it could inhibit the production of matrix metalloproteinases-1. The present research will contribute to the development of the compounds as anti-aging ingredients for future applications in cosmetic formulations and functional food as well as promote further studies of raw materials containing alike compounds.

Metabolomics and physiological analyses reveal β-sitosterol as an important plant growth regulator inducing tolerance to water stress in white clover

β-sitosterol influences amino acids, carbohydrates, organic acids, and other metabolite metabolism and homeostasis largely contributing to better tolerance to water stress in white clover. β-sitosterol (BS) could act as an important plant growth regulator when plants are subjected to harsh environmental conditions. Objective of this study was to examine effects of BS on growth and water stress tolerance in white clover based on physiological responses and metabolomics. White clover was pretreated with or without BS and then subjected to water stress for 7 days in controlled growth chambers. Physiological analysis demonstrated that exogenous application of BS (120 μM) could significantly improve stress tolerance associated with better growth performance and photosynthesis, higher leaf relative water content, and less oxidative damage in white clover in response to water stress. Metabolic profiling identified 78 core metabolites involved in amino acids, organic acids, sugars, sugar alcohols, and other metabolites in leaves of white clover. For sugars and sugar alcohol metabolism, the BS treatment enhanced the accumulation of fructose, glucose, maltose, and myo-inositol contributing to better antioxidant capacity, growth maintenance, and osmotic adjustment in white clover under water stress. The application of BS was inclined to convert glutamic acid into proline, 5-oxoproline, and chlorophyll instead of going to pyruvate and alanine; the BS treatment did not significantly affect intermediates of tricarboxylic acid cycle (citrate, aconitate, and malate), but promoted the accumulation of other organic acids including lactic acid, glycolic acid, glyceric acid, shikimic acid, galacturonic acid, and quinic acid in white clover subjected to water stress. In addition, cysteine, an important antioxidant metabolite, was also significantly improved by BS in white clover under water stress. These altered amino acids and organic acids metabolism could play important roles in growth maintenance and modulation of osmotic and redox balance against water stress in white clover. Current findings provide a new insight into BS-induced metabolic homeostasis related to growth and water stress tolerance in plants.

Phytochemical analysis and evaluation of the antioxidant and antiproliferative effects of Tucumã oil nanocapsules in breast adenocarcinoma cells (MCF-7)

In this work was to develop an inedited nanocapsule with tucumã oil (Astrocaryum vulgare). The oil presents of phytosterols (squalene and β-sitosterol), all-trans-beta-carotene, acids oleic and palmitic. Antioxidant activity showed a good performance in DPPH and ABTS assays. The nanocapsules were prepared and demonstrated in their characterization particle size (206 ± 0.69 nm). The cytogenotoxicity evaluation was performed using the MTT, dichlorofluorescein, nitric oxide and dsDNA PicoGreen® assays. Antitumor efficacy assays in MCF-7 cells demonstrated that free oil and tucumã nanocapsules had IC₅₀ of 130 and 50 μg/mL, respectively. Thus, previous studies of toxicity are relevant, as they generate future subsidies, aiming at the potential application of nanostructures and in addition, the promising effect of NCs of tucumã oil on the antiproliferative effect in breast adenocarcinoma cells was evidenced.

Edible oleogels: an opportunity for fat replacement in foods

The scientific and industrial communities have been giving great attention to the development of new bio-based materials with potential use in innovative technological applications. Among these materials are the structures with gel-like behavior that can be used in the cosmetic, pharmaceutical and food industries, aiming at controlling the physical properties of the final products. In the past ten years, words like oleogels and organogels have been increasingly used, the existing number of manuscripts and patents being proof of this tendency. In the food industry, oleogels can be used to control phase separation, and decrease the mobility and migration of the oil phase, providing solid-like properties without using high levels of saturated fatty acids as well as to be a carrier of bioactive compounds. In most cases, their main features are related to the reorganization process of gelators after an increase of the temperature, above the melting or glass transition temperature of the materials, known as the direct method, but it is also possible to develop oleogels by indirect methods, such as emulsification and the solvent exchange technique. In the direct methods, the reorganization is able to physically entrap oil leading to different physicochemical properties, the rheological behavior and texture properties being the frequently most studied ones. This review overviews the use of food grade and bio-based structurants to produce edible oleogels, aiming at fat replacement and structure-tailoring. Gelation mechanisms and oil phases used during oleogel production are discussed, as well as the current food applications and future trends for this kind of structure.

Critical Analysis on Characterization, Systemic Effect, and Therapeutic Potential of Beta-Sitosterol: A Plant-Derived Orphan Phytosterol

Beta-sitosterol (BS) is a phytosterol, widely distributed throughout the plant kingdom and known to be involved in the stabilization of cell membranes. To compile the sources, physical and chemical properties, spectral and chromatographic analytical methods, synthesis, systemic effects, pharmacokinetics, therapeutic potentials, toxicity, drug delivery and finally, to suggest future research with BS, classical as well as on-line literature were studied. Classical literature includes classical books on ethnomedicine and phytochemistry, and the electronic search included Pubmed, SciFinder, Scopus, the Web of Science, Google Scholar, and others. BS could be obtained from different plants, but the total biosynthetic pathway, as well as its exact physiological and structural function in plants, have not been fully understood. Different pharmacological effects have been studied, but most of the mechanisms of action have not been studied in detail. Clinical trials with BS have shown beneficial effects in different diseases, but long-term study results are not available. These have contributed to its current status as an "orphan phytosterol". Therefore, extensive research regarding its effect at cellular and molecular level in humans as well as addressing the claims made by commercial manufacturers such as the cholesterol lowering ability, immunological activity etc. are highly recommended.