Fyn kinase is a direct molecular target of delphinidin for the inhibition of cyclooxygenase-2 expression induced by tumor necrosis factor-alpha

Blackcurrants shape gut microbiota profile and reduce risk of postmenopausal osteoporosis via the gut-bone axis: Evidence from a pilot randomized controlled trial

This study aimed to investigate the effects of blackcurrant (BC) on gut microbiota abundance and composition, inflammatory and immune responses, and their relationship with bone mass changes. The effects of BC on bone mineral density (BMD), gut microbiota, and blood inflammatory and immune biomarkers were evaluated using DXA, stool and fasting blood collected from a pilot three-arm, randomized, double-blind, placebo-controlled clinical trial. Fifty-one peri- and early postmenopausal women aged 45-60 years were randomly assigned into one of three treatment groups for 6 months: control, low BC (392 mg/day) and high BC (784 mg/day); and 40 women completed the trial. BC supplementation for 6 months effectively mitigated the loss of whole-body BMD (P<.05). Six-month changes (%) in peripheral IL-1β (P=.056) and RANKL (P=.052) for the high BC group were marginally significantly lower than the control group. Six-month changes in whole-body BMD were inversely correlated with changes in RANKL (P<.01). In proteome analysis, four plasma proteins showed increased expression in the high BC group: IGFBP4, tetranectin, fetuin-B, and vitamin K-dependent protein S. BC dose-dependently increased the relative abundance of Ruminococcus 2 (P<.05), one of six bacteria correlated with BMD changes in the high BC group (P<.05), suggesting it might be the key bacteria that drove bone protective effects. Daily BC consumption for 6 months mitigated bone loss in this population potentially through modulating the gut microbiota composition and suppressing osteoclastogenic cytokines. Larger-scale clinical trials on the potential benefits of BC and connection of Ruminococcus 2 with BMD maintenance in postmenopausal women are warranted. Trial Registration: NCT04431960, https://classic.clinicaltrials.gov/ct2/show/NCT04431960.

Dihydromyrcenol Modulates Involucrin Expression through the Akt Signaling Pathway

The epidermis serves as a protective barrier against external threats and is primarily composed of keratinocytes, which ultimately form corneocytes. Involucrin, a protein integral to the cornified envelope, plays a pivotal role in preserving the functional integrity of the skin barrier. Previous studies have shown that Akt plays an important role in keratinocyte differentiation and skin barrier development. This study investigated whether dihydromyrcenol (DHM), a plant-derived terpene, could increase involucrin production in keratinocytes and sought to elucidate the possible underlying mechanisms. To accomplish this objective, we assessed the alterations in involucrin by DHM through quantitative PCR and Western blot on the HaCaT cell line. The changes in the promoter levels were investigated using luciferase assays. Furthermore, upstream mechanisms were explored through the use of siRNA and inhibitors. To strengthen our findings, the results were subsequently validated in primary cells and 3D skin equivalents. DHM significantly increased involucrin mRNA and protein levels in a concentration-dependent manner. In addition, the Fyn-Akt signaling pathway was found to be required for DHM-induced involucrin expression, as inhibition of Fyn or Akt blocked the increase in involucrin mRNA induced by DHM. The transcription factor Sp1, which is recognized as one of the transcription factors for involucrin, was observed to be activated in response to DHM treatment. Moreover, DHM increased epidermal thickness in a 3D human skin model. These findings suggest that the modulation of involucrin expression with DHM could improve skin barrier function and highlight the importance of manipulating the Akt pathway to achieve this improvement.

Comprehensive and critical view on the anti-inflammatory and immunomodulatory role of natural phenolic antioxidants

The immune response encompasses innate and adaptive immunity, each with distinct and specific activities. The innate immune system is constituted by phagocytic cells, macrophages, monocytes and neutrophils, the cascade system, and different classes of receptors such as toll-like receptors that are exploited by the innate immune cells. The adaptive immune system is antigen-specific, encompassing memory lymphocytes and the corresponding specific receptors. Inflammation is understood as an activation of different signaling pathways such as toll-like receptors or nuclear factor kappa-light-chain-enhancer of activated B cells, with an increase in nitric oxide, inflammatory cytokines and chemokines. Increased oxidative stress has been identified as main source of chronic inflammation. Phenolic antioxidants modulate the activities of lymphocytes and macrophages by impacting cytokines and nitric oxide release, exerting anti-inflammatory effect. The nuclear-factor kappa-light-chain-enhancer of activated B cells signaling pathway and the mitogen-activated protein kinase pathway are targeted, alongside an increase in nuclear factor erythroid 2-related factor mediated antioxidant response, triggering the activity of antioxidant enzymes. The inhibitive potential on phospholipase A2, cyclooxygenase and lipoxygenase in the arachidonic acid pathway, and the subsequent reduction in prostaglandin and leukotriene generation, reveals the potential of phenolics as inflammation antagonists. The immunomodulative potential encompasses the capacity to interfere with proinflammatory cytokine synthesis and with the expression of the corresponding genes. A diet rich in antioxidants can result in prevention of inflammation-related pathologies. More investigations are necessary to establish the role of these antioxidants in therapy. The appropriate delivery system and the prooxidant effects exhibited at large doses, or in the presence of heavy metal cations should be regarded.

Target discovery of bioactive natural products with native-compound-coupled CNBr-activated Sepharose 4B beads (NCCB): Applications, mechanisms and outlooks

Natural products (NPs) represent a treasure trove for drug discovery and development due to their chemical structural diversity and a broad spectrum of biological activities. Uncovering the biological targets and understanding their molecular mechanism of actions are crucial steps in the development of clinical therapeutics. However, the structural complexity of NPs and intricate nature of biological system present formidable challenges in target identification of NPs. Although significant advances have been made in the development of new chemical tools, these methods often require high levels of synthetic skills for preparing chemical probes. This can be costly and time-consuming relaying on operationally complicated procedures and instruments. In recent efforts, we and others have successfully developed an operationally simple and practical chemical tool known as native-compound-coupled CNBr-activated Sepharose 4B beads (NCCB) for NP target identification. In this approach, a native compound readily reacts with commercial CNBr-activated Sepharose 4B beads with a process that is easily performed in any biology laboratory. Based on NCCB, our group has identified the direct targets of more than 60 NPs. In this review, we will elucidate the application scopes, including flavonoids, quinones, terpenoids and others, characteristics, chemical mechanisms, procedures, advantages, disadvantages, and future directions of NCCB in specific target discovery.

Mur ligase F as a new target for the flavonoids quercitrin, myricetin, and (-)-epicatechin

MurC, D, E, and F are ATP-dependent ligases involved in the stepwise assembly of the tetrapeptide stem of forming peptidoglycan. As highly conserved targets found exclusively in bacterial cells, they are of significant interest for antibacterial drug discovery. In this study, we employed a computer-aided molecular design approach to identify potential inhibitors of MurF. A biochemical inhibition assay was conducted, screening twenty-four flavonoids and related compounds against MurC-F, resulting in the identification of quercitrin, myricetin, and (-)-epicatechin as MurF inhibitors with IC50 values of 143 µM, 139 µM, and 92 µM, respectively. Notably, (-)-epicatechin demonstrated mixed type inhibition with ATP and uncompetitive inhibition with D-Ala-D-Ala dipeptide and UM3DAP substrates. Furthermore, in silico analysis using Sitemap and subsequent docking analysis using Glide revealed two plausible binding sites for (-)-epicatechin. The study also investigated the crucial structural features required for activity, with a particular focus on the substitution pattern and hydroxyl group positions, which were found to be important for the activity. The study highlights the significance of computational approaches in targeting essential enzymes involved in bacterial peptidoglycan synthesis.

Chemistry and Pharmacological Actions of Delphinidin, a Dietary Purple Pigment in Anthocyanidin and Anthocyanin Forms

Anthocyanins are naturally occurring water-soluble flavonoids abundantly present in fruits and vegetables. They are polymethoxyderivatives of 2-phenyl-benzopyrylium or flavylium salts. Delphinidin (Dp) is a purple-colored plant pigment, which occurs in a variety of berries, eggplant, roselle, and wine. It is found in a variety of glycosidic forms ranging from glucoside to arabinoside. Dp is highly active in its aglycone form, but the presence of a sugar moiety is vital for its bioavailability. Several animal and human clinical studies have shown that it exerts beneficial effects on gut microbiota. Dp exhibits a variety of useful biological activities by distinct and complex mechanisms. This manuscript highlights the basic characteristics, chemistry, biosynthesis, stability profiling, chemical synthesis, physicochemical parameters along with various analytical methods developed for extraction, isolation and characterization, diverse biological activities and granted patents to this lead anthocyanin molecule, Dp. This review aims to open pathways for further exploration and research investigation on the true potential of the naturally occurring purple pigment (Dp) in its anthocyanidin and anthocyanin forms beyond nutrition.

Delphinidin diminishes in vitro interferon-γ and interleukin-17 producing cells in patients with psoriatic disease

The anthocyanidin delphinidin reduces psoriasiform lesions and inflammatory mediators in human cell culture systems. Its role in psoriatic disease has not yet been investigated. We assessed delphinidin's in vitro immunomodulatory effect on ex vivo stimulated peripheral blood mononuclear cells (PBMCs) from 50 individuals [26 with psoriasis, 10 with psoriatic arthritis (PsA) and 14 healthy controls (HCs)]. Cells were either left untreated or stimulated with PMA plus ionomycin in the presence or absence of delphinidin. Intracellular production of interferon-γ (IFNγ), interleukin-17A (IL-17A), and interleukin-10 (IL-10) was measured flow cytometrically. Delphinidin dose-dependently reduced IFNγ⁺ T cells from patients and HCs. The mean IFNγ decrease in CD4⁺ T subpopulations was 42.5 ± 28% for psoriasis patients, 51.8 ± 21.5% for PsA patients and 49 ± 17% for HCs (p < 0.001 for all). Similarly, IFNγ reduction in CD8⁺ T cells was 34 ± 21.6% for psoriasis patients, 47.1 ± 22.8% for PsA and 44.8 ± 14.3% for HCs (P < 0.001 for all). An inhibitory effect of delphinidin was also noted in IFNγ producing NKs and NKTs from psoriasis individuals. Delphinidin also significantly decreased IL-17⁺ CD4⁺ T cells in all tested subjects, with marginal effect on the increase of IL-10-producing T regulatory subsets. In conclusion, delphinidin exerts a profound in vitro anti-inflammatory effect in psoriasis and psoriatic arthritis by inhibiting IFNγ⁺ innate and adaptive cells and T helper (Th) 17 cells. If this effect is also exerted in vivo, delphinidin may be regarded as a nutraceutical with immunosuppressive potential.

Synergistic Interaction in the Analgesic-Like Effects of Maqui Berry and Citrus Is Antagonized by Sweeteners

Although physiologically pain has a protective function, in many diseases, it is one of the most prominent symptoms. Today, new trends are focused on finding more natural alternatives to conventional treatments to alleviate it. Thereby, the purpose of this investigation was to obtain preclinical data of the antinociceptive properties of a lyophilized obtained from a newly designed maqui-citrus beverage alone and added with different sweeteners. To achieve this objective, maqui berry and citrus pharmacological activity were studied separately, as well as the interaction of both ingredients. In addition, due to the controversy generated regarding the intake of sugars, related to different metabolic diseases, the influence of different sweeteners (stevia, sucralose, or sucrose) was studied to determine their possible influence on the bioactive compounds of this product. For the attainment of our goals, a pharmacological evaluation, using the 1% formalin test, a nociceptive pain model in mice, was performed by using a sub-efficacious dosage of Maqui (25 mg/kg, i.p.) alone and combined with citrus, and then compared with the effects obtained in the presence of the different sweeteners. As a result, the antinociceptive response of the maqui was synergized in the presence of citrus in the neurogenic and inflammatory phases of the formalin test. However, this response was partially or totally reduced in the presence of the sweeteners. Our study gives preclinical evidence that a combination of maqui and citrus might exert beneficial actions to relieve pain, whereas the presence of sweeteners could reduce or avoid it.

Antinociceptive effects of maqui-berry (Aristotelia chilensis (Mol.) Stuntz)

Maqui-berry is characterised by presenting a high concentration of (poly)phenols, accounting anthocyanins (cyanidin and delphinidin) for over 85% of the total. These coloured flavonoids have demonstrated potential neurological activity, but the evidence of their antinociceptive properties is scarce. In order to cover this gap, different doses (suitable for human administration) of a maqui-berry powder (1.6% anthocyanin), using enteral and parenteral routes of administration, were compared at central and peripheral levels using a nociceptive pain model (formalin test) in mice. Gastric damage analysis as possible adverse effects of analgesic and anti-inflammatory drugs was also explored. Dose-antinociceptive response was confirmed using both routes of administration and in both neurogenic and inflammatory phases of the formalin test, without gastric damage. In conclusion, these preliminary data provide evidence of pharmacological properties of maqui-berry to alleviate nociceptive pain.

Caffeoyl-Prolyl-Histidine Amide Inhibits Fyn and Alleviates Atopic Dermatitis-Like Phenotypes via Suppression of NF-κB Activation

Caffeic acid (CA) is produced from a variety of plants and has diverse biological functions, including anti-inflammation activity. It has been recently demonstrated that caffeoyl-prolyl-histidine amide (CA-PH), which is CA conjugated with proline-histidine dipeptide, relieves atopic dermatitis (AD)-like phenotypes in mouse. In this study, we investigated the molecular mechanism underlying CA-PH-mediated alleviation of AD-like phenotypes using cell line and AD mouse models. We confirmed that CA-PH suppresses AD-like phenotypes, such as increased epidermal thickening, infiltration of mast cells, and dysregulated gene expression of cytokines. CA-PH suppressed up-regulation of cytokine expression through inhibition of nuclear translocation of NF-κB. Using a CA-PH affinity pull-down assay, we found that CA-PH binds to Fyn. In silico molecular docking and enzyme kinetic studies revealed that CA-PH binds to the ATP binding site and inhibits Fyn competitively with ATP. CA-PH further suppressed spleen tyrosine kinase (SYK)/inhibitor of nuclear factor kappa B kinase (IKK)/inhibitor of nuclear factor kappa B (IκB) signaling, which is required for nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation. In addition, chronic application of CA-PH, in contrast with that of glucocorticoids, did not induce up-regulation of regulated in development and DNA damage response 1 (REDD1), reduction of mammalian target of rapamycin (mTOR) signaling, or skin atrophy. Thus, our study suggests that CA-PH treatment may help to reduce skin inflammation via down-regulation of NF-κB activation, and Fyn may be a new therapeutic target of inflammatory skin diseases, such as AD.

Fyn kinase mediates pro-inflammatory response in a mouse model of endotoxemia: Relevance to translational research

Systemic inflammation resulting from the release of pro-inflammatory cytokines and the chronic activation of the innate immune system remains a major cause of morbidity and mortality in the United States. After having demonstrated that Fyn, a Src family kinase, regulates microglial neuroinflammatory responses in cell culture and animal models of Parkinson's disease, we investigate here its role in modulating systemic inflammation using an endotoxic mouse model. Fyn knockout (KO) and their wild-type (WT) littermate mice were injected once intraperitoneally with either saline or 5 mg/kg lipopolysaccharide (LPS) and were killed 48 h later. LPS-induced mortality, endotoxic symptoms and hypothermia were significantly attenuated in Fyn KO, but not WT, mice. LPS reduced survival in Fyn WT mice to 49% compared to 84% in Fyn KO mice. Fyn KO mice were also protected from LPS-induced deficits in horizontal and vertical locomotor activities, total distance traveled and stereotypic movements. Surface body temperatures recorded at 24 h and 48 h post-LPS dropped significantly in Fyn WT, but not in KO, mice. Importantly, endotoxemia-associated changes to levels of the serum pro-inflammatory cytokines tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6), splenocyte apoptosis and inducible nitric oxide synthase (iNOS) production in hepatocytes were also significantly attenuated in Fyn KO mice. Likewise, pharmacologically inhibiting Fyn with 10 mg/kg dasatinib (oral) significantly attenuated LPS-induced increases in plasma TNF-α and IL-6 protein levels and hepatic pro-IL-1β messenger ribonucleic acids (mRNAs). Collectively, these results indicate that genetic knockdown or pharmacological inhibition of Fyn dampens systemic inflammation, demonstrating for the first time that Fyn kinase plays a critical role in mediating the endotoxic inflammatory response.

The Multifunctional Benefits of Naturally Occurring Delphinidin and Its Glycosides

Delphinidin (Del) and its glycosides are water-soluble pigments, belonging to a subgroup of flavonoids. They are health-promoting candidates for pharmaceutical and nutraceutical uses, as indicated by exhibiting antioxidation, anti-inflammation, antimicroorganism, antidiabetes, antiobesity, cardiovascular protection, neuroprotection, and anticancer properties. Glycosylation modification of Del is associated with increased stability and reduced biological activity. Del and its glycosides can be the alternative inhibitors of CBRs, ERα/β, EGFR, BCRP, and SGLT-1, and virtual docking indicates that the sugar moiety may not effectively interact with the active sites of the targets. Structure-based characteristics confer the multifunctional properties of Del and its glycosides. Because of their health-promoting effects, Del and its glycosides are promising and have been developed as potential pharmaceuticals. However, more investigation on the underlying mechanisms of Del and its glycosides in mediating cellular processes with high specificity are still needed. The research progression of Del and its glycosides over the last 10 years is comprehensively reviewed in this article.

A Close Look at Echium amoenum Processing, Neuroactive Components, and Effects on Neuropsychiatric Disorders

Pharmacological researches in the area of herbal medicine have considerably increased over the last two centuries. Echium amoenum (known as Gol-e-Gavzaban in Persian) is a medicinal plant that has been widely used in Iranian folk medicine. In this review, databases including PubMed, Scopus, and Google Scholar were searched up. Data collecting was completed by January 2019 and available scientific reports regarding the processing methods, main chemical constituents, and effects of E. amoenum on different neuropsychiatric disorders are summarized. Thirteen five studies met the inclusion criteria. According to results, the important phytochemicals of the plant was phenolic compounds, fatty acids, rosmarinic acid, anthocyanidins, and flavonoids. Also, experimental and clinical studies demonstrated the effectiveness of E. amoenum in the treatment of several neuropsychiatric disorders such as anxiety, depression, ischemic stroke, seizure, Alzheimer's disease, and pain. Many of these effects are, at least in part, due to its rosmarinic acid or polyphenolic compounds such as flavonoids and natural pigments such as anthocyanins. Also, fatty acids such as gamma-linolenic acid play critical role in neuroactive properties of this herb. Among these effects, only the antidepressant and anxiolytic properties of the plant extract have been examined both experimentally and clinically. There was some controversy over its toxicity effects. It seems that E. amoenum protects neurons via attenuation of oxidative stress and inflammation as well as blocking of apoptosis in the nervous system. However, more studies are necessary for assessing exact mechanisms of action in neuropsychiatric disorders, finding of bioactive ingredients, and processing methods of this plant.

Effect of hydroalcoholic Echium amoenum extract on scopolamine-induced learning and memory impairment in rats

CONTEXT

Scopolamine, a muscarinic receptor antagonist, causes memory loss that resembles Alzheimer's disease (AD). Echium amoenum L. (Boraginaceae) is a famous medicinal plant of Iran that is traditionally used as a sedative and mood enhancer.

OBJECTIVE

This study evaluates the effect of hydroalcoholic extract of E. amoenum flowers on scopolamine-induced memory impairment in rats.

MATERIALS AND METHODS

Fifty male Wistar rats were randomly divided into five groups. Control group received normal saline, model group received scopolamine (0.7 mg/kg, IP, daily for 21 days), and test groups received E. amoenum extract (50, 75, and 100 mg/kg, IP, daily for 21 days) 30 min before each scopolamine injection. The elevated plus maze (EPM), shuttle box, novel object and rotarod tests were performed after treatment. Brain levels of malondialdehyde (MDA) and total antioxidant capacity (TCA) were also determined.

RESULTS

Scopolamine-treated rats spent more time exploring the novel object compared to the control, and E. amoenum extract at all three doses significantly decreased the time spent exploring the novel object (p < 0.05). E. amoenum extract (75 and 100 mg/kg) significantly elongated the secondary latency in rats receiving scopolamine in the shuttle box test (p < 0.05). In addition, treatment with 75 and 100 mg/kg doses of E. amoenum extract significantly ameliorated scopolamine-induced motor in coordination in rotarod test (p < 0.05). It also significantly increased the time spent in the open arms and reduced the time spent in the closed arms of EPM (p < 0.05). Treatment of scopolamine-exposed rats with E. amoenum extract significantly increased TCA and reduced MDA level of brain (p < 0.05).

DISCUSSION AND CONCLUSIONS

E. amoenum extract shows protective effect against scopolamine-induced impairment and is suggested to be tested in clinical trials to evaluate the efficacy on AD.

Polyphenol Extracts from Red Wine and Grapevine: Potential Effects on Cancers

Wine has been popular worldwide for many centuries and currently remains an important component of our diet. Scientific interest in wine and its health effects has grown considerably since the 1990s with the emergence of the “French Paradox” concept, correlating moderate wine consumption, a characteristic of the Mediterranean diet, and low incidence of coronary heart diseases. Since then, the positive effects on health, health promotion, disease prevention, and disease prognosis of moderate wine consumption, in particular red wine, have been attributed to its polyphenolic compounds such as resveratrol, quercetin, and other flavonoids acting as antioxidants. Several epidemiological, in vivo and in vitro, studies have reported that moderate red wine or red wine polyphenolic extract consumption may be active in the prevention and treatment of chronic diseases such as cardiovascular disease, metabolic syndrome, degenerative pathologies, and cancer. The aim of this review is to summarize the current findings about the effects of red wine polyphenols on cancer and to discuss how the polyphenolic composition of red wine may influence its chemopreventive properties.

Polyphenol Extracts from Red Wine and Grapevine: Potential Effects on Cancers

Wine has been popular worldwide for many centuries and currently remains an important component of our diet. Scientific interest in wine and its health effects has grown considerably since the 1990s with the emergence of the "French Paradox" concept, correlating moderate wine consumption, a characteristic of the Mediterranean diet, and low incidence of coronary heart diseases. Since then, the positive effects on health, health promotion, disease prevention, and disease prognosis of moderate wine consumption, in particular red wine, have been attributed to its polyphenolic compounds such as resveratrol, quercetin, and other flavonoids acting as antioxidants. Several epidemiological, in vivo and in vitro, studies have reported that moderate red wine or red wine polyphenolic extract consumption may be active in the prevention and treatment of chronic diseases such as cardiovascular disease, metabolic syndrome, degenerative pathologies, and cancer. The aim of this review is to summarize the current findings about the effects of red wine polyphenols on cancer and to discuss how the polyphenolic composition of red wine may influence its chemopreventive properties.

Anti-inflammatory effect of delphinidin on intramedullary spinal pressure in a spinal cord injury rat model

Delphinidin, a flavonoid polyphenolic compound, is widely found in nature and is used as a food supplement due to its pharmacological activity. The aims of the present study were to examine the anti-inflammatory effect of delphinidin in alleviating spinal cord injury (SCI)-induced inflammation in a rat model and to determine the underlying mechanisms in SCI. The Basso, Beattie, Bresnahan (BBB) scores of rats were assessed to evaluate the effect of delphinidin on the recovery of motor function. ELISA kits were also used to analyze the activities of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2) and caspase-3. In addition, the protein expression levels of nuclear factor (NF)-κB, activator protein 1 (AP-1) and p38-MAPK protein expression were measured using western blot analysis. Treatment with delphinidin significantly increased the BBB scores, as well as inhibited the intramedullary spinal pressure in SCI rats. Delphinidin treatment also significantly suppressed the levels of inflammatory factors and NF-κB protein expression in SCI rats. Finally, treatment with delphinidin significantly inhibited NF-κB stimulation, COX-2 activity, PGE2 production, and AP-1 and p38-MAPK protein expression in SCI rats. These results suggest that the anti-inflammatory effect of delphinidin alleviated inflammation in the SCI rat model via alleviation of the intramedullary spinal pressure through the NF-κB and p38-MAPK signaling pathways.

GRID and docking analyses reveal a molecular basis for flavonoid inhibition of Src family kinase activity

Flavonoids reduce cardiovascular disease risk through anti-inflammatory, anti-coagulant and anti-platelet actions. One key flavonoid inhibitory mechanism is blocking kinase activity that drives these processes. Flavonoids attenuate activities of kinases including phosphoinositide-3-kinase, Fyn, Lyn, Src, Syk, PKC, PIM1/2, ERK, JNK and PKA. X-ray crystallographic analyses of kinase-flavonoid complexes show that flavonoid ring systems and their hydroxyl substitutions are important structural features for their binding to kinases. A clearer understanding of structural interactions of flavonoids with kinases is necessary to allow construction of more potent and selective counterparts. We examined flavonoid (quercetin, apigenin and catechin) interactions with Src family kinases (Lyn, Fyn and Hck) applying the Sybyl docking algorithm and GRID. A homology model (Lyn) was used in our analyses to demonstrate that high-quality predicted kinase structures are suitable for flavonoid computational studies. Our docking results revealed potential hydrogen bond contacts between flavonoid hydroxyls and kinase catalytic site residues. Identification of plausible contacts indicated that quercetin formed the most energetically stable interactions, apigenin lacked hydroxyl groups necessary for important contacts and the non-planar structure of catechin could not support predicted hydrogen bonding patterns. GRID analysis using a hydroxyl functional group supported docking results. Based on these findings, we predicted that quercetin would inhibit activities of Src family kinases with greater potency than apigenin and catechin. We validated this prediction using in vitro kinase assays. We conclude that our study can be used as a basis to construct virtual flavonoid interaction libraries to guide drug discovery using these compounds as molecular templates.

Protective effects of Echium amoenum Fisch. and C.A. Mey. against cerebral ischemia in the rats

Background:

This study was designed to evaluate the protective effect of Echium amoenum total anthocyanin extract (ETAE) on partial/transient cerebral ischemia in the rats.

Materials and Methods:

Rats received ETAE (50, 100 and 200 mg/kg, i.p.) 30 min before the induction of cerebral ischemia. Cerebral ischemia was induced by bilateral common carotid arteries occlusion (BCCAO) for 30 min, followed by 72 h reperfusion. The neurological deficit, brain performance, and sensory motor function were assessed 48 h and 72 h after surgery. After sacrification, the brains were evaluated for myeloperoxidase (MPO) activity and histopathological changes.

Results:

Our results showed that motor function significantly decreased in ischemia/reperfusion (I/R) group as compared to the sham group. Histopathological analysis exhibited the shrinkage and atrophy of the neurons in I/R group. ETAE at the dose of 200 mg/kg improved spontaneous activity and memory induced by cerebral ischemia compared to the control group and also decreased brain MPO activity following cerebral ischemia. However, it could not affect the ability to climbing, body proprioception, vibrissae touch and brain water content. In addition, pretreatment with ETAE at higher doses significantly reduced ischemia-induced neuronal loss of the brain.

Conclusion:

The anthocyanin rich fraction from E. amoenum was found to have protective effects against some brain damages postischemic reperfusion. However, further researches are required for investigating the exact mechanisms of the effect of this plant in the prevention of cerebral ischemia in human.

Phytochemical regulation of Fyn and AMPK signaling circuitry

During the past decades, phytochemical terpenoids, polyphenols, lignans, flavonoids, and alkaloids have been identified as antioxidative and cytoprotective agents. Adenosine monophosphate-activated protein kinase (AMPK) is a kinase that controls redox-state and oxidative stress in the cell, and serves as a key molecule regulating energy metabolism. Many phytochemicals directly or indirectly alter the AMPK pathway in distinct manners, exerting catabolic metabolism. Some of them are considered promising in the treatment of metabolic diseases such as type II diabetes, obesity, and hyperlipidemia. Another important kinase that regulates energy metabolism is Fyn kinase, a member of the Src family kinases that plays a role in various cellular responses such as insulin signaling, cell growth, oxidative stress and apoptosis. Phytochemical inhibition of Fyn leads to AMPK-mediated protection of the cell in association with increased antioxidative capacity and mitochondrial biogenesis. The kinases may work together to form a signaling circuitry for the homeostasis of energy conservation and expenditure, and may serve as targets of phytochemicals. This review is intended as a compilation of recent advancements in the pharmacological research of phytochemicals targeting Fyn and AMPK circuitry, providing information for the prevention and treatment of metabolic diseases and the accompanying tissue injuries.

Enforced expression of miR-101 enhances cisplatin sensitivity in human bladder cancer cells by modulating the cyclooxygenase-2 pathway

Alterations in microRNA (miRNA) expression have been shown to be involved in the tumor response to chemotherapy. However, the possible role of miR‑101 in cisplatin sensitivity in human bladder cancer cells remains unclear. In this study, quantitative polymerase chain reaction and western blotting were utilized to determine the expression profiles of miR‑101 and cyclooxygenase‑2 (COX‑2) in human bladder cancer cells. The effect of miR‑101 and small interfering RNA (siRNA) against COX‑2 on cell viability was evaluated using MTT assays, and apoptosis levels were determined using fluorescence‑activated cell sorting analysis of Annexin V/propidium iodide‑stained cells. Luciferase reporter plasmids were constructed to confirm direct targeting. This study found that the expression of miR‑101 was downregulated in the cisplatin‑resistant cell line T24/CDDP as compared with that in the parental line, T24. Furthermore, overexpression of miR‑101 significantly increased the anti‑proliferative effects and apoptosis induced by cisplatin, whereas knockdown of miR‑101 significantly decreased the anti‑proliferative effects and apoptosis induced by cisplatin. In addition, downregulation of miR‑101 induced cell survival and cisplatin resistance through the upregulation of COX‑2 expression. Luciferase gene reporter assays confirmed that COX‑2 was a direct target gene of miR‑101. Inhibition of COX‑2 using COX‑2 siRNA abrogated the cisplatin resistance induced by miR‑101 downregulation. These results suggest that miR‑101 may provide a novel mechanism for understanding cisplatin resistance in bladder cancer by modulating the COX‑2 pathway.

Investigating flavonoids as molecular templates for the design of small-molecule inhibitors of cell signaling

Epidemiological and clinical trials reveal compelling evidence for the ability of dietary flavonoids to lower cardiovascular disease risk. The mechanisms of action of these polyphenolic compounds are diverse, and of particular interest is their ability to function as protein and lipid kinase inhibitors. We have previously described structure-activity studies that reinforce the possibility for using flavonoid structures as templates for drug design. In the present study, we aim to begin constructing rational screening strategies for exploiting these compounds as templates for the design of clinically relevant, antiplatelet agents. We used the platelet as a model system to dissect the structural influence of flavonoids, stilbenes, anthocyanidins, and phenolic acids on inhibition of cell signaling and function. Functional groups identified as relevant for potent inhibition of platelet function included at least 2 benzene rings, a hydroxylated B ring, a planar C ring, a C ring ketone group, and a C-2 positioned B ring. Hydroxylation of the B ring with either a catechol group or a single C-4' hydroxyl may be required for efficient inhibition of collagen-stimulated tyrosine phosphorylated proteins of 125 to 130 kDa, but may not be necessary for that of phosphotyrosine proteins at approximately 29 kDa. The removal of the C ring C-3 hydroxyl together with a hydroxylated B ring (apigenin) may confer selectivity for 37 to 38 kDa phosphotyrosine proteins. We conclude that this study may form the basis for construction of maps of flavonoid inhibitory activity on kinase targets that may allow a multitargeted therapeutic approach with analogue counterparts and parent compounds.

NADPH oxidase is a novel target of delphinidin for the inhibition of UVB-induced MMP-1 expression in human dermal fibroblasts

We investigated the reported antiphotoaging effects of the major anthocyanidin delphidin and sought to identify its specific molecular target during UVB-induced MMP-1 expression. Delphinidin treatment significantly inhibited UVB-induced MMP-1 expression in primary cultured human dermal fibroblasts (HDF), an effect associated with the suppression of MKK4-JNK1/2, MKK3/6-p38 and MEK-ERK1/2 phosphorylation. Further investigation revealed that delphinidin significantly inhibited UVB-induced ROS production and NOX activity. Interestingly, the inhibitory effect of delphinidin on UVB-induced NOX activity was stronger than that of apocynin, a pharmaceutical NOX inhibitor. Fractioned cell analysis results using a Western blot assay showed that this effect occurred through the inhibition of UVB-induced P47(phox) (a NOX subunit) translocation from the cytosol to the membrane. Pull down assays demonstrated that delphinidin binds directly to P47(phox) in vitro. Collectively, our results suggest that delphinidin targets NOX, resulting in the suppression of UVB-induced MMP-1 expression in human dermal fibroblasts.

The molecular basis for the pharmacokinetics and pharmacodynamics of curcumin and its metabolites in relation to cancer

This review addresses the oncopharmacological properties of curcumin at the molecular level. First, the interactions between curcumin and its molecular targets are addressed on the basis of curcumin's distinct chemical properties, which include H-bond donating and accepting capacity of the β-dicarbonyl moiety and the phenylic hydroxyl groups, H-bond accepting capacity of the methoxy ethers, multivalent metal and nonmetal cation binding properties, high partition coefficient, rotamerization around multiple C-C bonds, and the ability to act as a Michael acceptor. Next, the in vitro chemical stability of curcumin is elaborated in the context of its susceptibility to photochemical and chemical modification and degradation (e.g., alkaline hydrolysis). Specific modification and degradatory pathways are provided, which mainly entail radical-based intermediates, and the in vitro catabolites are identified. The implications of curcumin's (photo)chemical instability are addressed in light of pharmaceutical curcumin preparations, the use of curcumin analogues, and implementation of nanoparticulate drug delivery systems. Furthermore, the pharmacokinetics of curcumin and its most important degradation products are detailed in light of curcumin's poor bioavailability. Particular emphasis is placed on xenobiotic phase I and II metabolism as well as excretion of curcumin in the intestines (first pass), the liver (second pass), and other organs in addition to the pharmacokinetics of curcumin metabolites and their systemic clearance. Lastly, a summary is provided of the clinical pharmacodynamics of curcumin followed by a detailed account of curcumin's direct molecular targets, whereby the phenotypical/biological changes induced in cancer cells upon completion of the curcumin-triggered signaling cascade(s) are addressed in the framework of the hallmarks of cancer. The direct molecular targets include the ErbB family of receptors, protein kinase C, enzymes involved in prostaglandin synthesis, vitamin D receptor, and DNA.

Novel factors in the pathogenesis of psoriasis and potential drug candidates are found with systems biology approach

Psoriasis is a multifactorial inflammatory skin disease characterized by increased proliferation of keratinocytes, activation of immune cells and susceptibility to metabolic syndrome. Systems biology approach makes it possible to reveal novel important factors in the pathogenesis of the disease. Protein-protein, protein-DNA, merged (containing both protein-protein and protein-DNA interactions) and chemical-protein interaction networks were constructed consisting of differentially expressed genes (DEG) between lesional and non-lesional skin samples of psoriatic patients and/or the encoded proteins. DEGs were determined by microarray meta-analysis using MetaOMICS package. We used STRING for protein-protein, CisRED for protein-DNA and STITCH for chemical-protein interaction network construction. General network-, cluster- and motif-analysis were carried out in each network. Many DEG-coded proteins (CCNA2, FYN, PIK3R1, CTGF, F3) and transcription factors (AR, TFDP1, MEF2A, MECOM) were identified as central nodes, suggesting their potential role in psoriasis pathogenesis. CCNA2, TFDP1 and MECOM might play role in the hyperproliferation of keratinocytes, whereas FYN may be involved in the disturbed immunity in psoriasis. AR can be an important link between inflammation and insulin resistance, while MEF2A has role in insulin signaling. A controller sub-network was constructed from interlinked positive feedback loops that with the capability to maintain psoriatic lesional phenotype. Analysis of chemical-protein interaction networks detected 34 drugs with previously confirmed disease-modifying effects, 23 drugs with some experimental evidences, and 21 drugs with case reports suggesting their positive or negative effects. In addition, 99 unpublished drug candidates were also found, that might serve future treatments for psoriasis.

Effect of Echium amoenum Fisch. et Mey a Traditional Iranian Herbal Remedy in an Experimental Model of Acute Pancreatitis

Acute pancreatitis is a morbid inflammatory condition of pancreas with limited specific therapy. Enhanced oxidative stress plays an important role in induction and progression of acute pancreatitis. So reducing oxidative stress may relieve this pathogenic process. Echium amoenum Fisch. and Mey has been implemented in Iranian folk medicine for several centuries. Antioxidant, analgesic, immunomodulatory, and anxiolytic properties of E. amoenum suggest that this plant may have beneficial effects in the management of acute pancreatitis. The aim of this study was to evaluate the protective effect of petals of E. amoenum extract (EAE) on a murine model of pancreatitis. Acute pancreatitis was induced by five intraperitoneal (i.p.) injection of cerulein (50 μg/kg) with 1h intervals which was characterized by pancreatic inflammation and increase in the serum level of digestive enzymes, in comparison to normal mice. EAE (100, 200, and 400 mg/kg) was administered i.p., 30 minutes before induction of pancreatitis. Pretreatment with EAE (400 mg/kg) reduced significantly the inflammatory response of cerulein-induced acute pancreatitis by ameliorating pancreatic edema, amylase and lipase serum levels, proinflammatory cytokines, myeloperoxidase activity, lipid peroxidation and pathological alteration. These results show that EAE attenuates the severity of cerulein-induced acute pancreatitis with an anti-inflammatory, immunomodulatory and antioxidant effects.

Molecular mechanisms of the cardiovascular protective effects of polyphenols

Epidemiological studies have reported a greater reduction in cardiovascular risk and metabolic disorders associated with diets rich in polyphenols. The antioxidant effects of polyphenols are attributed to the regulation of redox enzymes by reducing reactive oxygen species production from mitochondria, NADPH oxidases and uncoupled endothelial NO synthase in addition to also up-regulating multiple antioxidant enzymes. Although data supporting the effects of polyphenols in reducing oxidative stress are promising, several studies have suggested additional mechanisms in the health benefits of polyphenols. Polyphenols from red wine increase endothelial NO production leading to endothelium-dependent relaxation in conditions such as hypertension, stroke or the metabolic syndrome. Numerous molecules contained in fruits and vegetables can activate sirtuins to increase lifespan and silence metabolic and physiological disturbances associated with endothelial NO dysfunction. Although intracellular pathways involved in the endothelial effects of polyphenols are partially described, the molecular targets of these polyphenols are not completely elucidated. We review the novel aspects of polyphenols on several targets that could trigger the health benefits of polyphenols in conditions such as metabolic and cardiovascular disturbances.

Target molecules of food phytochemicals: food science bound for the next dimension

Phytochemicals are generally defined as secondary metabolites in plants that play crucial roles in their adaptation to a variety of environmental stressors. There is a great body of compelling evidence showing that these metabolites have pronounced potentials for regulating and modulating human health and disease onset, as shown by both experimental and epidemiological approaches. Concurrently, enormous efforts have been made to elucidate the mechanism of actions underlying their biological and physiological functions. For example, the pioneering work of Tachibana et al. uncovered the receptor for (-)-epigallocatechin-3-gallate (EGCg) as the 67 kDa laminin receptor, which was shown to partially mediate the functions of EGCg, such as anti-inflammatory, anti-allergic, and anti-proliferative activities. Thereafter, several protein kinases were identified as binding proteins of flavonoids, including myricetin, quercetin, and kaempferol. Isothiocyanates, sulfur-containing phytochemicals present in cruciferous plants, are well known to target Keap1 for activating the transcription factor Nrf2 for inducing self-defensive and anti-oxidative gene expression. In addition, we recently identified CD36 as a cell surface receptor for ursolic acid, a triterpenoid ubiquitously occurring in plants. Importantly, the above mentioned target proteins are indispensable for phytochemicals to exhibit, at least in part, their bioactivities. Nevertheless, it is reasonable to assume that some of the activities and potential toxicities of metabolites are exerted via their interactions with unidentified, off-target proteins. This notion may be supported by the fact that even rationally designed drugs occasionally display off-target effects and induce unexpected outcomes, including toxicity. Here we update the current status and future directions of research related to target molecules of food phytochemicals.

Cyanidin-3-glucoside suppresses B[a]PDE-induced cyclooxygenase-2 expression by directly inhibiting Fyn kinase activity

Benzo[a]pyrene-7,8-diol-9,10-epoxide (B[a]PDE) is a well-known carcinogen that is associated with skin cancer. Abnormal expression of cyclooxygenase-2 (COX-2) is an important mediator in inflammation and tumor promotion. We investigated the inhibitory effect of cyanidin-3-glucoside (C3G), an anthocyanin present in fruits, on B[a]PDE-induced COX-2 expression in mouse epidermal JB6 P+ cells. Pretreatment with C3G resulted in the reduction of B[a]PDE-induced expression of COX-2 and COX-2 promoter activity. The activation of activator protein-1 (AP-1) and nuclear factor-κB (NF-κB) induced by B[a]PDE was also attenuated by C3G. C3G attenuated the B[a]PDE-induced phosphorylation of MEK, MKK4, Akt, and mitogen-activated protein kinases (MAPKs), but no effect on the phosphorylation of the upstream MAPK regulator Fyn. However, kinase assays demonstrated that C3G suppressed Fyn kinase activity and C3G directly binds Fyn kinase noncompetitively with ATP. By using PP2, a pharmacological inhibitor for SFKs, we showed that Fyn kinase regulates B[a]PDE-induced COX-2 expression by activating MAPKs, AP-1 and NF-κB. These results suggest that C3G suppresses B[a]PDE-induced COX-2 expression mainly by blocking the activation of the Fyn signaling pathway, which may contribute to its chemopreventive potential.

Molecular targets of phytochemicals for cancer prevention

Although successful for a limited number of tumour types, the efficacy of cancer therapies, especially for late-stage disease, remains poor overall. Many have argued that this could be avoided by focusing on cancer prevention, which has now entered the arena of targeted therapies. During the process of identifying preventive agents, dietary phytochemicals, which are thought to be safe for human use, have emerged as modulators of key cellular signalling pathways. The task now is to understand how these chemicals perturb these pathways by modelling their interactions with their target proteins.

Polyphenols as small molecular inhibitors of signaling cascades in carcinogenesis

Multiple lines of evidences suggest that oxidative stress induced by reactive oxygen species are closely related to multi-stage carcinogenesis. Polyphenols, a group of chemicals with more than one phenol unit or building block per molecule, have been recognized for possessing many health benefits including cancer-preventive effects mainly due to their antioxidant activity. However, polyphenols can directly bind with signaling molecules involved in carcinogenesis and regulate its activity. Moreover, it is noteworthy that the binding between the polyphenol and the target protein is determined by their structural relationship, which implies that different polyphenols have different target proteins, leading to divergent chemopreventive effects. Extracellular stimuli transmit signals into a cell by activating their target signaling cascades involved in carcinogenesis. As an example, Src family kinase, a family of proto-oncogenic tyrosine kinases activated by a variety of oxidative stress and proinflammatory agents, is known to regulate cell proliferation, differentiation, survival and angiogenesis. Src family kinase subsequently activates downstream signal cascades including mitogen-activated protein kinase, phosphoinositol-3-kinase, and nuclear factor-kappaB, thereby inducing cell proliferation and causing cancer. Recent studies demonstrate that polyphenols can directly target signaling cascades involved in inflammation and the development of cancer. Inhibition of the kinases by polyphenols contributes to the attenuation of carcinogenesis. Therefore, the development of polyphenols as direct inhibitors against target proteins is regarded as a rational approach for chemoprevention. This review describes and discusses recent results about the direct interactions of polyphenols and protein kinases in cancer chemoprevention.

Flavonoids as protein kinase inhibitors for cancer chemoprevention: direct binding and molecular modeling

Protein kinases play crucial roles in the regulation of multiple cell signaling pathways and cellular functions. Deregulation of protein kinase function has been implicated in carcinogenesis. The inhibition of protein kinases has emerged as an important target for cancer chemoprevention and therapy. Accumulated data revealed that flavonoids exert chemopreventive effects through acting at protein kinase signaling pathways, more than as conventional hydrogen-donating antioxidants. Recent studies show that flavonoids can bind directly to some protein kinases, including Akt/protein kinase B (Akt/PKB), Fyn, Janus kinase 1 (JAK1), mitogen-activated protein kinase kinase 1 (MEK1), phosphoinositide 3-kinase (PI3K), mitogen-activated protein (MAP) kinase kinase 4 (MKK4), Raf1, and zeta chain-associated 70-kDa protein (ZAP-70) kinase, and then alter their phosphorylation state to regulate multiple cell signaling pathways in carcinogenesis processes. In this review, we report recent results on the interactions of flavonoids and protein kinases, especially their direct binding and molecular modeling. The data suggest that flavonoids act as protein kinase inhibitors for cancer chemoprevention that were thought previously as conventional hydrogen-donating antioxidant. Moreover, the molecular modeling data show some hints for creating natural compound-based protein kinase inhibitors for cancer chemoprevention and therapy.