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Scientific research on tomato products has demonstrated an array of health benefits. A comprehensive examination of current research indicates that the carotenoid lycopene contributes to various benefits through its synergistic relationship with other micronutrients. [ABSTRACT FROM AUTHOR]

The activity of cAMP-dependent and cAMP-independent protein kinases, a class of enzymes involved in the regulation of cell proliferation was measured in rat colonic epithelium. Sequential cell populations harvested by a stepwise scraping technique from colonic crypt regions were identified by histology and incorporation of [3H]-thymidine into DNA. cAMP-independent phosphorylation of casein, in the presence of [gamma-32P]ATP, was markedly suppressed by quercetin, a bioflavonoid known to inhibit G-type casein kinase, protein kinase-C and tyrosine protein kinase. Conversely, the cyclic nucleotide regulatable form requiring histone as substrate was responsive to the action of the heat stable protein kinase inhibitor. The protein kinase species were characterised and partially purified by DEAE-cellulose chromatography. The activity of cAMP-dependent protein kinase in colonic cytosols (pmol 32P/min/mg protein, means (SE)) increased from 129.4 (15.9) in superficial cell populations to 238.5 (31.4) in lower crypt cell fractions (p less than 0.01). Colonic cAMP-independent protein kinase activity increased from 87.3 (15.6) in surface cell preparations to 178.1 (30.0) in lower crypt cell populations (p less than 0.02). A comparable activity gradient was observed in membrane fractions. The activity gradient persisted when the results were expressed as a function of cellular DNA. These findings indicate that protein kinases display a defined topological segregation along the colonic crypt regions and that during migration to the lumen colonic cells attenuate enzyme signals supposedly related to tissue growth. [ABSTRACT FROM PUBLISHER]

This study was undertaken to investigate a possible relationship between endogenous secretion of growth hormone (GH) during ovarian stimulation and treatment outcome in patients undergoing in-vitro fertilization (IVF) and embryo transfer. Plasma samples obtained from 19 women who had successfully completed all stages of IVF/embryo transfer were analysed retrospectively. Based on the increase in GH during treatment, 11 GH responders and eight GH non-responders were identified. Mean daily GH concentrations for the GH responders and GH non-responders were 3.5 +/- 1.8 and 1.8 +/- 0.8, 5.4 +/- 2.3 and 0.5 +/- 0.2, and 9.0 +/- 1.9 and 0.7 +/- 0.1 ng/ml (P < 0.05) for days 10, 11 and 12 respectively. Plasma insulin-like growth factor-I slightly increased with treatment in both groups. No significant difference between these groups was found in relation to treatment duration, number of human menopausal gonadotrophin ampoules used, oestradiol peak values, and number of oocytes retrieved or fertilization rate. Seven of the 11 GH responder women conceived in comparison with one pregnancy among eight GH non-responder patients (P < 0.05). In view of the absence of differences in the clinical and laboratory parameters, we suggest that the occurrence of pregnancies among GH responder patients might be related to a positive local effect of GH or its mediators on uterine receptivity at the time of nidation. [ABSTRACT FROM AUTHOR]

Skin aging is associated with the increased production of mitochondrial reactive oxygen species (mtROS) due to mitochondrial dysfunction, and various phytonutrients and estrogens have been shown to improve skin health. Thus, the aim of the current study was to examine damage to dermal fibroblasts by chemically induced mitochondrial dysfunction and to study the mechanism of the protective effects of carotenoids, polyphenols, and estradiol. Rotenone, a Complex I inhibitor, caused mitochondrial dysfunction in human dermal fibroblasts, substantially reducing respiration and ATP levels, followed by increased mitochondrial and cytosolic ROS, which resulted in apoptotic cell death, an increased number of senescent cells, increased matrix metalloproteinase-1 (MMP1) secretion, and decreased collagen secretion. Pre-treatment with carotenoid-rich tomato extracts, rosemary extract, and estradiol reversed these effects. These protective effects can be partially explained by a cooperative activation of antioxidant response element (ARE/Nrf2) transcriptional activity by the protective compounds and rotenone, which led to the upregulation of antioxidant proteins such as NQO1. To determine if ARE/Nrf2 activity is crucial for cell protection, we inhibited it using the Nrf2 inhibitors ML385 and ochratoxin A. This inhibition markedly reduced the protective effects of the test compounds by diminishing their effect to reduce cytosolic ROS. Our study results indicate that phytonutrients and estradiol protect skin cells from damage caused by mtROS, and thus may delay skin cell senescence and improve skin health.

Background: Cellular metabolism and exposure to solar irradiation result in generation of free radicals which are destructive and can lead to premature aging. Antioxidants and free radical scavengers such as carotenoids successfully protect from these free radicals by quenching and neutralizing them thereby strengthening skin barrier which leads to improved skin moisturization, desquamation, and a more youthful look. This study was designed to evaluate the consumer-perceived efficacy of an oral supplement (Lumenato™) containing a mix of tomato carotenoids and oil-soluble vitamins in improving skin appearance after 12 weeks of supplement use., Materials and Methods: Plasma levels of phytoene, phytofluene, zeta-carotene, and lycopene were quantitated before and after 1-, 2-, 3-, and 4-week administration of Lumenato by 24 healthy volunteers. Part II of the study addressed skin visual attributes as assessed by validated tools (questionnaires). A total of 60 females, aged 35 to 55 years, completed part II of the study. The subjects answered questionnaires pertaining to their assessment of skin appearance before and after 12 weeks of taking the supplement., Results: There was a significant increase (p < 0.001) in plasma levels of phytoene, phytofluene, and zeta-carotene after 1- to 4-week treatment with Lumenato. After 12 weeks of using the supplement, the score of different skin parameters was reported to significantly improve (p < 0.001). Improvement was recorded in skin elasticity, firmness, brightness, skin tone, reduction in dark spots and periorbital dark circles, skin hydration, texture and fine lines and wrinkles. A significant (p < 0.001) improvement in overall skin condition after using the supplement was observed. The subjects noticed statistically significant (p < 0.001) improvement in skin elasticity, firmness, brightness, skin tone, reduction in dark spots and periorbital dark circles, skin hydration, texture and fine lines and wrinkles after 12 weeks of using the supplement. The overall skin condition also exhibited a significant improvement (p < 0.001). Self-assessed improvement of the face was identified at the first time point (4 weeks) and improved significantly (p < 0.001) for the 12 weeks of use. Interestingly, these improvements persisted even after treatment was stopped., Conclusion: Based on the confines and conditions of this study, the use of oral supplement containing a mix of tomato carotenoids significantly increased plasma levels of phytoene, phytofluene, and zeta-carotene, and continuous use resulted in improved facial skin attributes which were palpable by the consumers and continued even after treatment was stopped., (© 2021 Lycored LTD. Journal of Cosmetic Dermatology published by Wiley Periodicals LLC.)

Scope: Two experiments were performed to test the effects of rich tomato extract (Golden Tomato Extract, GTE) on human skin. In one experiment, the effects of this extract on gene expression in cultured human dermal fibroblasts were examined. In a second experiment, human subjects consumed the extract and trans-epidermal water loss (TEWL), and aspects of skin appearance were monitored., Methods and Results: Primary human dermal fibroblasts in culture were treated with the extract. After six hours, RNA was extracted, and gene expression was examined using Affymetrix Human Clariom D array processing. For the clinical study, 65 human subjects consumed a capsule once a day for 16 weeks, and various skin parameters were assessed at predetermined time intervals. Among the genes upregulated by GTE are genes that augment innate immunity, enhance DNA repair, and the ability to detoxify xenobiotics. GTE significantly reduced TEWL in subjects who had high TEWL at baseline, but it had no effect on TEWL in subjects who had lower TEWL at baseline., Conclusions: Golden tomato extract may provide benefits to the skin by enhancing innate immunity and other defense mechanisms in the dermis and by providing antioxidants to the skin surface to optimize TEWL and the appearance of the skin., (© 2021 Lycored. Journal of Cosmetic Dermatology published by Wiley Periodicals LLC.)

Microgravity is known to impact bone health, similar to mechanical unloading on Earth. In the absence of countermeasures, bone formation and mineral deposition are strongly inhibited in Space. There is an unmet need to identify nutritional countermeasures. Curcumin and carnosic acid are phytonutrients with anticancer, anti-inflammatory, and antioxidative effects and may exhibit osteogenic properties. Zinc is a trace element essential for bone formation. We hypothesized that these nutraceuticals could counteract the microgravity-induced inhibition of osteogenic differentiation and function. To test this hypothesis, we cultured 7F2 murine osteoblasts in simulated microgravity (SMG) in a Random Positioning Machine in the presence and absence of curcumin, carnosic acid, and zinc and evaluated cell proliferation, function, and differentiation. SMG enhanced cell proliferation in osteogenic medium. The nutraceuticals partially reversed the inhibitory effects of SMG on alkaline phosphatase (ALP) activity and did not alter the SMG-induced reduction in the expression of osteogenic marker genes in osteogenic medium, while they promoted osteoblast proliferation and ALP activity in the absence of traditional osteogenic media. We further observed a synergistic effect of the intermix of the phytonutrients on ALP activity. Intermixes of phytonutrients may serve as convenient and effective nutritional countermeasures against bone loss in space.

Skin ageing is influenced by several factors including environmental exposure and hormonal changes. Reactive oxygen species (ROS), which mediate many of the effects of these factors, induce inflammatory processes in the skin and increase the production of matrix metalloproteinases (MMPs) in dermal fibroblasts, which leads to collagen degradation. Several studies have shown the protective role of estrogens and a diet rich in fruits and vegetables on skin physiology. Previous studies have shown that dietary carotenoids and polyphenols activate the cell's antioxidant defense system by increasing antioxidant response element/Nrf2 (ARE/Nrf2) transcriptional activity and reducing the inflammatory response. The aim of the current study was to examine the protective effect of such dietary-derived compounds and estradiol on dermal fibroblasts under oxidative stress induced by H 2 O 2 . Human dermal fibroblasts were used to study the effect of H 2 O 2 on cell number and apoptosis, MMP-1, and pro-collagen secretion as markers of skin damage. Treatment of cells with H 2 O 2 led to cell death, increased secretion of MMP-1, and decreased pro-collagen secretion. Pre-treatment with tomato and rosemary extracts, and with estradiol, reversed the effects of the oxidative stress. This was associated with a reduction in intracellular ROS levels, probably through the measured increased activity of ARE/Nrf2. Conclusions: This study indicates that carotenoids, polyphenols, and estradiol protect dermal fibroblasts from oxidative stress-induced damage through a reduction in ROS levels.

Dietary intake and tissue levels of carotenoids have been associated with a reduced risk of several chronic diseases, including cardiovascular diseases, type 2 diabetes, obesity, brain-related diseases and some types of cancer. However, intervention trials with isolated carotenoid supplements have mostly failed to confirm the postulated health benefits. It has thereby been speculated that dosing, matrix and synergistic effects, as well as underlying health and the individual nutritional status plus genetic background do play a role. It appears that our knowledge on carotenoid-mediated health benefits may still be incomplete, as the underlying mechanisms of action are poorly understood in relation to human relevance. Antioxidant mechanisms - direct or via transcription factors such as NRF2 and NF-κB - and activation of nuclear hormone receptor pathways such as of RAR, RXR or also PPARs, via carotenoid metabolites, are the basic principles which we try to connect with carotenoid-transmitted health benefits as exemplified with described common diseases including obesity/diabetes and cancer. Depending on the targeted diseases, single or multiple mechanisms of actions may play a role. In this review and position paper, we try to highlight our present knowledge on carotenoid metabolism and mechanisms translatable into health benefits related to several chronic diseases.

Anticancer activities of plant polyphenols have been demonstrated in various models of neoplasia. However, evidence obtained in numerous in vitro studies indicates that proliferation arrest and/or killing of cancer cells require quite high micromolar concentrations of polyphenols that are difficult to reach in vivo and can also be (geno)toxic to at least some types of normal cells. The ability of certain polyphenols to synergize with one another at low concentrations can be used as a promising strategy to effectively treat human malignancies. We have recently reported that curcumin and carnosic acid applied at non-cytotoxic concentrations synergistically cooperate to induce massive apoptosis in acute myeloid leukemia cells, but not in normal hematopoietic and non-hematopoietic cells, via sustained cytosolic calcium overload. Here, we show that the two polyphenols can also synergistically suppress the growth of DU145 and PC-3 metastatic prostate cancer cell cultures. However, instead of cell killing, the combined treatment induced a marked inhibition of cell proliferation associated with G 0 /G 1 cell cycle arrest. This was preceded by transient elevation of cytosolic calcium levels and prolonged dissipation of the mitochondrial membrane potential, without generating oxidative stress, and was associated with defective oxidative phosphorylation encompassing mitochondrial dysfunction. The above effects were concomitant with a significant downregulation of mRNA and protein expression of the oncogenic kinase SGK1, the mitochondria-hosted mTOR component. In addition, a moderate decrease in SGK1 phosphorylation at Ser422 was observed in polyphenol-treated cells. The mTOR inhibitor rapamycin produced a similar reduction in SGK1 mRNA and protein levels as well as phosphorylation. Collectively, our findings suggest that the combination of curcumin and carnosic acid at potentially bioavailable concentrations may effectively target different types of cancer cells by distinct modes of action. This and similar combinations merit further exploration as an anticancer modality.

In the last few decades, Endocrine Disrupting Chemicals (EDCs) have taken significant roles in creating harmful effects to aquatic organisms. Many proposed treatment applications are time consuming, expensive and focus mainly on waste water treatment plants (WWTP), which are indeed a major aquatic polluting source. Nonetheless, the marine environment is the ultimate sink of many pollutants, e.g. EDCs, and has been largely neglected mainly due to the challenge in treating such salty and immense open natural ecosystems. In this study we describe the bromination and the yet unpresented degradation process of high concentrations (5 mg/L) of phenolic EDCs, by the marine red macroalgaeGracilaria sp. As shown, 17α-Ethinylestradiol (EE2), a well-known contraceptive drug, and one of the most persistent phenol EDCs in the environment, was eliminated from both the medium and tissues of the macroalga, in addition to the degradation of all metabolites as verified by the nil estrogenic activity recorded in the medium. Validation of the proposed bromination-degradation route was reinforced by identifying Bisphenol A (BPA) brominated degradation products only, following 168H of incubation in the presence of Gracilaria sp. As demonstrated in this assay for EE2, BPA and finally for paracetamol, it is likely that the phenol scavenging activity is nonspecific and, thus, possibly even a wider scope of various other phenol-based pollutants might be treated in coastal waters. As far as we know, Gracilaria sp. is the only marine sessile organism able of degrading various phenol based pollutants. The worldwide distribution of many Gracilaria species and their wide aquaculture knowhow, suggest that bioremediation based on these seaweeds is a possible cost effective progressive solution to the treatment of a wide scope of phenols at the marine environment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Among the vast variety of plant-derived phytochemicals, the group of carotenoids has continuously been investigated in order to optimize their potential application in the area of dietary intervention and medicine. One organ which has been especially targeted in many of these studies and clinical trials is the human prostate. Without doubt, carotenoids (and their endogenous derivatives-retinoids and other apo-carotenoids) are involved in intra- and intercellular signaling, cell growth and differentiation of prostate tissue. Due to the accumulation of new data on the role of different carotenoids such as lycopene (LC) and β-carotene (BC) in prostatic physiology and pathology, the present review aims to cover the past ten years of research in this area. Data from experimental studies are presented in the first part of the review, while epidemiological studies are disclosed and discussed in the second part. The objective of this compilation is to emphasize the present state of knowledge regarding the most potent molecular targets of carotenoids and their main metabolites, as well as to propose promising carotenoid agents for the prevention and treatment of prostatic diseases.

Oral carotenoids and polyphenols have been suggested to induce photo-protective effects. The aim of the study was to test whether the combination of carotenoids and polyphenols produce greater protective effects from UV-induced damage to skin cells. Such damage is characterized by inflammation and oxidative stress; thus, the photo-protective effect can be partially explained by modulating the nuclear factor kappa B (NFκB) and antioxidant response element/Nrf2 (ARE/Nrf2) transcription systems, known as important regulators of these two processes. Indeed, it was found in keratinocytes that carotenoids and polyphenols inhibit UVB-induced NFκB activity and release of cytokine IL-6. A combination of tomato extract with rosemary extract inhibited UVB-induced release of IL-6 more than each of the compounds alone. Moreover, this combination synergistically activated ARE/Nrf2 transcription systems. Inflammatory cytokines such as IL-6 and TNFα induce the expression of matrix metalloproteinases (MMPs), which leads to collagen breakdown; thus, it is important to note that carnosic acid reduced TNFα-induced MMP-1 secretion from human dermal fibroblasts. The in vitro results suggest beneficial effects of phytonutrient combinations on skin health. To assure that clinical experiments to prove such effects in humans are feasible, the human bioavailability of carotenoids from tomato extract was tested, and nearly a twofold increase in their plasma concentrations was detected. This study demonstrates that carotenoids and polyphenols cooperate in balancing UV-induced skin cell damage, and suggests that NFκB and ARE/Nrf2 are involved in these effects.

Among the vast variety of plant-derived phytochemicals, the group of carotenoids has continuously been investigated in order to optimize their potential application in the area of dietary intervention related to chronic diseases. One organ that has been especially targeted in many of these studies and clinical trials is the human prostate. Without doubt, carotenoids (and their endogenous derivatives-retinoids and apo-carotenoids) are involved in a plethora of intra- and intercellular signaling, cell growth, and differentiation of prostate tissue. Due to the accumulation of new data on the role of different carotenoids, such as lycopene (LYC) and β-carotene (BC), in prostatic physiology and pathology, the present review aimed to cover the past ten years of research in this regard. Data from experimental studies are presented in the first part of the review, while epidemiological studies are disclosed in this second part. The objective of this compilation was to emphasize the present state of knowledge about the most potent molecular targets of carotenoids, as well as to propose promising carotenoid agents for the prevention and possible treatment of prostatic diseases.

The bone protective effects of carotenoids have been demonstrated in several studies, and the inhibition of RANKL-induced osteoclast differentiation by lycopene has also been demonstrated. We previously reported that carotenoid oxidation products are the active mediators in the activation of the transcription factor Nrf2 and the inhibition of the NF-ƙB transcription system by carotenoids. Here, we demonstrate that lycopene oxidation products are more potent than intact lycopene in inhibiting osteoclast differentiation. We analyzed the structure-activity relationship of a series of dialdehyde carotenoid derivatives (diapocarotene-dials) in inhibiting osteoclastogenesis. We found that the degree of inhibition depends on the electron density of the carbon atom that determines the reactivity of the conjugated double bond in reactions such as Michael addition to thiol groups in proteins. Moreover, the carotenoid derivatives attenuated the NF-ƙB signal through inhibition of IƙB phosphorylation and NF-ƙB translocation to the nucleus. In addition, we show a synergistic inhibition of osteoclast differentiation by combinations of an active carotenoid derivative with the polyphenols curcumin and carnosic acid with combination index (CI) values < 1. Our findings suggest that carotenoid derivatives inhibit osteoclast differentiation, partially by inhibiting the NF-ƙB pathway. In addition, carotenoid derivatives can synergistically inhibit osteoclast differentiation with curcumin and carnosic acid.

Oxidative stress is implicated in the pathogenesis of essential hypertension, a risk factor for cardiovascular morbidity and mortality. Tomato carotenoids such as lycopene and the colorless carotenoids phytoene and phytofluene induce the antioxidant defense mechanism. This double-blind, randomized, placebo-controlled study aimed to find effective doses of Tomato Nutrient Complex (TNC) to maintain normal blood pressure in untreated hypertensive individuals. The effect of TNC treatment (5, 15 and 30 mg lycopene) was compared with 15 mg of synthetic lycopene and a placebo over eight weeks. Results indicate that only TNC treatment standardized for 15 or 30 mg of lycopene was associated with significant reductions in mean systolic blood pressure (SBP). Treatment with the lower dose standardized for 5 mg of lycopene or treatment with 15 mg of synthetic lycopene as a standalone had no significant effect. To test carotenoid bioavailability, volunteers were treated for four weeks with TNC providing 2, 5 or 15 mg lycopene. The increase in blood levels of lycopene, phytoene, and phytofluene was dose dependent. Results suggest that only carotenoid levels achieved by the TNC dose of 15 mg lycopene or higher correlate to a beneficial effect on SBP in hypertensive subjects while lower doses and lycopene alone do not.

Acute myeloid leukemia (AML) is an aggressive hematologic malignancy characterized by extremely heterogeneous molecular and biologic abnormalities that hamper the development of effective targeted treatment modalities. While AML cells are highly sensitive to cytotoxic Ca2+ overload, the feasibility of Ca2+- targeted therapy of this disease remains unclear. Here, we show that apoptotic response of AML cells to the synergistically acting polyphenols curcumin (CUR) and carnosic acid (CA), combined at low, non-cytotoxic doses of each compound was mediated solely by disruption of cellular Ca2+ homeostasis. Specifically, activation of caspase cascade in CUR+CA-treated AML cells resulted from sustained elevation of cytosolic Ca2+ (Ca2+cyt) and was not preceded by endoplasmic reticulum stress or mitochondrial damage. The CUR+CA-induced Ca2+cyt rise did not involve excessive influx of extracellular Ca2+ but, rather, occurred due to massive Ca2+ release from intracellular stores concomitant with inhibition of Ca2+cyt extrusion through the plasma membrane. Notably, the CUR+CA combination did not alter Ca2+ homeostasis and viability in non-neoplastic hematopoietic cells, suggesting its cancer-selective action. Most importantly, co-administration of CUR and CA to AML-bearing mice markedly attenuated disease progression in two animal models. Collectively, our results provide the mechanistic and translational basis for further characterization of this combination as a prototype of novel Ca2+-targeted pharmacological tools for the treatment of AML., Competing Interests: The authors declare no conflicts of interest.

Epidemiological studies have consistently shown that regular consumption of fruits and vegetables is strongly associated with reduced risk of developing chronic diseases, such as cancer. It is now accepted that the actions of any specific phytonutrient alone do not explain the observed health benefits of diets rich in fruits and vegetables as nutrients that were taken alone in clinical trials did not show consistent preventive effects. The considerable cost and complexity of such clinical trials requires prudent selection of combinations of ingredients rather than single compounds. Indeed, synergistic inhibition of prostate and mammary cancer cell growth was evident when using combinations of low concentrations of various carotenoids or carotenoids with retinoic acid and the active metabolite of vitamin-D. In this study we aimed to develop simple and sensitive in vitro methods which provide information on potent combinations suitable for inclusion in clinical studies for cancer prevention. We, thus, used reporter gene assays of the transcriptional activity of the androgen receptor in hormone-dependent prostate cancer cells and of the electrophile/antioxidant response element (EpRE/ARE) transcription system. We found that combinations of several carotenoids (e.g., lycopene, phytoene and phytofluene), or carotenoids and polyphenols (e.g., carnosic acid and curcumin) and/or other compounds (e.g., vitamin E) synergistically inhibit the androgen receptor activity and activate the EpRE/ARE system. The activation of EpRE/ARE was up to four fold higher than the sum of the activities of the single ingredients, a robust hallmark of synergy. Such combinations can further be tested in the more complex in vivo models and human studies., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Aberrant activation of the nuclear factor kappa B (NFkB) transcription system contributes to cancer progression, and has a harmful effect on bone health. Several major components of the NFkB pathway such as IkB Kinase (IKK) and the NFkB subunits contain cysteine residues that are critical for their activity. The interaction of electrophiles with these cysteine residues results in NFkB inhibition. Carotenoids, hydrophobic plant pigments, are devoid of electrophilic groups, and we have previously demonstrated that carotenoid derivatives, but not the native compounds activate the Nrf2 transcription system. The aim of the current study was to examine whether carotenoid derivatives inhibit NFkB, and, if so, to determine the molecular mechanism underpinning the inhibitory action. We report in the present study that a mixture of oxidized derivatives, prepared by ethanol extraction from partially oxidized lycopene preparation, inhibited NFkB reporter gene activity. In contrast, the intact carotenoid was inactive. A series of synthetic dialdehyde carotenoid derivatives inhibited reporter activity as well as several stages of the NFkB pathway in both cancer and bone cells. The activity of the carotenoid derivatives depended on the reactivity of the electrophilic groups in reactions such as Michael addition to sulfhydryl groups of proteins. Specifically, carotenoid derivatives directly interacted with two key proteins of the NFkB pathway: the IKKβ and the p65 subunit. Direct interaction with IKKβ was found in an in vitro kinase assay with a recombinant enzyme. The inhibition by carotenoid derivatives of p65 transcriptional activity was observed in a reporter gene assay performed in the presence of excess p65. This inhibition action resulted, at least in part, from direct interaction of the carotenoid derivative with p65 leading to reduced binding of the protein to DNA as evidenced by electrophoretic mobility shift assay (EMSA) experiments. Importantly, we found by using mutation in key cysteine residues of both p65 and IKK that specific thiol groups are essential for NFkB inhibition by carotenoid derivatives. In conclusion, we propose that electrophilic carotenoid derivatives contribute to cancer prevention as well as bone health maintenance via the inhibition of the NFkB transcription system. Pivotal thiol groups of both IKK and p65 play a key role in this process., (Copyright © 2014 Elsevier Inc. All rights reserved.)