Administration of Piceatannol Complexed with α-Cyclodextrin Improves Its Absorption in Rats

Predicting phase-I metabolism of piceatannol: an in silico study

Piceatannol is a natural compound found in plants and can be derived from resveratrol. While resveratrol has been extensively researched for its effects and how the body processes it, there are concerns about its use. These concerns include its limited absorption in the body, the need for specific dosages, potential interactions with other drugs, lack of standardization, and limited clinical evidence to support its benefits. Interestingly, Piceatannol, another compound derived from resveratrol, has received less attention from researchers but appears to offer advantages. It has better bioavailability and seems to have a more favorable therapeutic profile compared to resveratrol. Surprisingly, no previous attempts have been made to explore or predict the metabolites of piceatannol when it interacts with the enzyme cytochrome P450. This study aims to fill that gap by predicting how piceatannol is metabolized by cytochrome P450 and assessing any potential toxicity associated with its metabolites. This research is interesting because it's the first of its kind to investigate the metabolic fate of piceatannol, especially in the context of cytochrome P450. The findings have the potential to significantly contribute to the field of piceatannol research, particularly in the food industry where this compound has applications and implications.

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Exploring the therapeutic potential of naturally occurring piceatannol in non-communicable diseases

Piceatannol is a naturally occurring hydroxylated resveratrol analogue that can be found in a variety of fruits and vegetables. It has been documented to have a wide range of beneficial effects, including anti-inflammatory, antioxidant, anti-aging, anti-allergic, antidiabetic, neuroprotective, cardioprotective, and chemopreventive properties. Piceatannol has significantly higher antioxidant activity than resveratrol. Piceatannol has been shown in preclinical studies to have the ability to inhibit or reduce the growth of cancers in various organs such as the brain, breast, lung, colon, cervical, liver, prostate, and skin. However, the bioavailability of Piceatannol is comparatively lower than resveratrol and other stilbenes. Several approaches have been reported in recent years to enhance its bioavailability and biological activity, and clinical trials are required to validate these findings. This review focuses on several aspects of natural stilbene Piceatannol, its chemistry, and its mechanism of action, and its promising therapeutic potential for the prevention and treatment of a wide variety of complex human diseases.

The anti-Toxoplasma activity of the plant natural phenolic compound piceatannol

Toxoplasma gondii is an obligate intracellular protozoan that infects the nucleated cells of warm-blooded animals and causes life-threatening disease in immunocompromised patients. Due to the limited effectiveness and prominent side effects of existing drugs, there is an urgent need to develop new therapeutic options against T. gondii. Piceatannol is a natural plant compound with multiple functions such as antibacterial, antileukemic and antiparasitic activities. In the present study, the anti-T. gondii activity of piceatannol was evaluated. Piceatannol potently inhibited Toxoplasma with a half-maximal effective concentration (EC₅₀) of 28.10 μM. Piceatannol showed a significant inhibitory effect on intracellular proliferation, inhibiting intracellular parasites at a rate of 98.9% when treatment with 100 μM piceatannol. However, the invasion ability of tachyzoites was not affected by piceatannol. By immunofluorescence assay, we noted that the parasite showed abnormalities in cell division after exposure to piceatannol. To determine the in vivo effect of piceatannol on acute infection, a model was established by infecting BALB/c mice with the virulent RH strain of T. gondii. Mice infected with 500 tachyzoites showed a significant therapeutic effect when treated with 15 mg/kg of piceatannol. These results suggest that piceatannol is a promising drug for the treatment of T. gondii.

Biotransformation of Piceatannol, a Dietary Resveratrol Derivative: Promises to Human Health

SCOPE

To evaluate the health-promoting potentials of piceatannol (PIC), a dietary resveratrol derivative, its biotransformation is examined.

METHODS AND RESULTS

The biotransformation is tested in human/rat hepatic microsomes and cytosols; its pharmacokinetic profiles are assessed in rats. Although limited phase I metabolism exists in microsomes, PIC is rapidly converted to two pharmacologically active metabolites, namely rhapontigenin (RHA) and isorhapontigenin (ISO) in cytosols. Such biotransformation is completely blocked by entacapone, a well-known catechol-O-methyltransferase (COMT) inhibitor, demonstrating that the O-methylation is mediated by COMT. Moreover, PIC is identified as a substrate inhibitor of COMT, suggesting its potential benefits in Alzheimer's disease. Due to extensive phase II metabolism including glucuronidation, sulfation, and O-methylation, PIC displays rapid clearance and at least 4.02% ± 0.61% and 17.70% ± 0.91% of PIC is converted to RHA and ISO, respectively, in rats after intravenous administration. Similarly, PIC serves as an effective precursor of ISO upon oral administration.

CONCLUSION

Since PIC and its metabolites possess pleiotropic health-promoting activities, it has emerged as a promising nutraceutical candidate for further development. This study also reinforces the importance of in vivo testing in nutritional researches as the active metabolite(s) may be absent from the in vitro system.

Albumin Nano-Encapsulation of Piceatannol Enhances Its Anticancer Potential in Colon Cancer Via Downregulation of Nuclear p65 and HIF-1α

Piceatannol (PIC) is known to have anticancer activity, which has been attributed to its ability to block the proliferation of cancer cells via suppression of the NF-kB signaling pathway. However, its effect on hypoxia-inducible factor (HIF) is not well known in cancer. In this study, PIC was loaded into bovine serum albumin (BSA) by desolvation method as PIC–BSA nanoparticles (NPs). These PIC–BSA nanoparticles were assessed for in vitro cytotoxicity, migration, invasion, and colony formation studies and levels of p65 and HIF-1α. Our results indicate that PIC–BSA NPs were more effective in downregulating the expression of nuclear p65 and HIF-1α in colon cancer cells as compared to free PIC. We also observed a significant reduction in inflammation induced by chemical colitis in mice by PIC–BSA NPs. Furthermore, a significant reduction in tumor size and number of colon tumors was also observed in the murine model of colitis-associated colorectal cancer, when treated with PIC–BSA NPs as compared to free PIC. The overall results indicate that PIC, when formulated as PIC–BSA NPs, enhances its therapeutic potential. Our work could prompt further research in using natural anticancer agents as nanoparticels with possible human clinical trails. This could lead to the development of a new line of safe and effective therapeutics for cancer patients.

Progress to Improve Oral Bioavailability and Beneficial Effects of Resveratrol

Resveratrol (3,5,4'-trihydroxystilbene; RSV) is a natural nonflavonoid polyphenol present in many species of plants, particularly in grapes, blueberries, and peanuts. Several in vitro and in vivo studies have shown that in addition to antioxidant, anti-inflammatory, cardioprotective and neuroprotective actions, it exhibits antitumor properties. In mammalian models, RSV is extensively metabolized and rapidly eliminated and therefore it shows a poor bioavailability, in spite it of its lipophilic nature. During the past decade, in order to improve RSV low aqueous solubility, absorption, membrane transport, and its poor bioavailability, various methodological approaches and different synthetic derivatives have been developed. In this review, we will describe the strategies used to improve pharmacokinetic characteristics and then beneficial effects of RSV. These methodological approaches include RSV nanoencapsulation in lipid nanocarriers or liposomes, nanoemulsions, micelles, insertion into polymeric particles, solid dispersions, and nanocrystals. Moreover, the biological results obtained on several synthetic derivatives containing different substituents, such as methoxylic, hydroxylic groups, or halogens on the RSV aromatic rings, will be described. Results reported in the literature are encouraging but require additional in vivo studies, to support clinical applications.

The Therapeutic Potential of Piceatannol, a Natural Stilbene, in Metabolic Diseases: A Review

Metabolic disease comprises a set of risk factors highly associated with obesity and insulin resistance and is a consequence of central adiposity, hyperglycemia, and dyslipidemia. Furthermore, obesity increases the risk of the development of metabolic disease due to ectopic fat deposition, low-grade inflammation, and systemic energy disorders caused by dysregulated adipose tissue function. Piceatannol is a naturally occurring polyphenolic stilbene found in various fruits and vegetables and has been reported to exhibit anticancer and anti-inflammatory properties. In addition, recently reported beneficial effects of piceatannol on hypercholesterolemia, atherosclerosis, and angiogenesis underscore its therapeutic potential in cardiovascular disease. However, investigation of its role in metabolic disease is still in its infancy. This review intensively summarizes in vitro and in vivo studies supporting the potential therapeutic effects of piceatannol in metabolic disease, including inhibition of adipogenesis and lipid metabolism in adipocytes, and regulation of hyperlipidemia, hyperglycemia, insulin resistance, and fatty acid-induced inflammation and oxidative stress.

Piceatannol Attenuates Renal Fibrosis Induced by Unilateral Ureteral Obstruction via Downregulation of Histone Deacetylase 4/5 or p38-MAPK Signaling

Piceatannol, a resveratrol metabolite, is a phenolic compound found in red wine and grapes. We investigated the effect of piceatannol on renal fibrosis and histone deacetylase (HDAC) expression in a mouse model of unilateral ureteral obstruction (UUO). Fibrosis was established by UUO and piceatannol was intraperitoneally injected for 2 weeks. Piceatannol suppressed extracellular matrix (ECM) protein deposition including collagen type I and fibronectin as well as connective tissue growth factor (CTGF) and α-smooth muscle actin (α-SMA) in UUO kidneys. However, the expressions of epithelial-mesenchymal transition (EMT) marker genes, such as N-cadherin and E-cadherin, were not changed in the kidneys after UUO. Masson’s trichrome staining and fluorescence immunostaining showed that piceatannol administration attenuated collagen deposition in UUO kidneys. HDAC1, HDAC4, HDAC5, HDAC6, and HDAC10 protein expression was upregulated in UUO kidneys, whereas that of HDAC8 was downregulated. Piceatannol treatment significantly reduced HDAC4 and HDAC5 protein expression. Further, piceatannol attenuated phosphorylation of p38 mitogen-activated protein kinase (p38-MAPK) in UUO kidneys, but not that of transforming growth factor beta1-Smad2/3. These results suggest that class I HDACs and class IIa/b HDACs are involved in renal fibrosis development. Piceatannol may be a beneficial therapeutic agent for treating renal fibrosis via reduction of HDAC4 and HDAC5 protein expression or suppression of the p38-MAPK signaling pathway.