Associations between serum carotenoid levels and the risk of non-Hodgkin lymphoma: a case-control study.

Limited studies have investigated the effects of serum carotenoids on the risk of non-Hodgkin lymphoma (NHL), and the findings have been inconclusive. This study aims to assess the association between serum total or specific carotenoid levels and NHL risk. This 1:1 matched, hospital-based case-control study enrolled 512 newly diagnosed (within 1 month) NHL patients and 512 healthy controls who were matched by age (±5 years) and sex in Urumqi, China. Serum carotenoid levels were measured by HPLC. Conditional logistic regression showed that higher serum total carotenoid levels and their subtypes (e.g. α-carotene, ß-carotene, ß-cryptoxanthin and lycopene) were dose-dependently associated with decreased NHL risk. The multivariable-adjusted OR and their 95 % CI for NHL risk for quartile 4 (v. quartile 1) were 0·31 (95 % CI 0·22, 0·48; Pfor trend < 0·001) for total carotenoids, 0·52 (95 % CI 0·33, 0·79; Pfor trend: 0·003) for α-carotene, 0·63 (95 % CI 0·42, 0·94; Pfor trend: 0·031) for ß-carotene, 0·73 (95 % CI 0·49, 1·05; Pfor trend: 0·034) for ß-cryptoxanthin and 0·51 (95 % CI 0·34, 0·75; Pfor trend: 0·001) for lycopene. A null association was observed between serum lutein + zeaxanthin and NHL risk (OR 0·89, 95 % CI 0·57, 1·38; Pfor trend: 0·556). Significant interactions were observed after stratifying according to smoking status, and inverse associations were more evident among current smokers than past or never smokers for total carotenoids, α-carotene and lycopene (Pfor heterogeneity: 0·047, 0·042 and 0·046). This study indicates that higher serum carotenoid levels might be inversely associated with NHL risk, especially among current smokers.

Serum carotenoids and colorectal cancer risk: A case-control study in Guangdong, China.

SCOPE: Previous epidemiological studies on the association between circulating carotenoids and the risk of colorectal cancer drew inconclusive conclusions. This study aimed to examine serum carotenoids in relation to colorectal cancer risk in a Chinese population. METHODS AND RESULTS: One case-control study beginning from July 2010, consecutively recruited 538 eligible colorectal cancer cases and 564 age (5-year interval) and sex frequency-matched controls. Serum levels of α-carotene, ß-carotene, ß-cryptoxanthin, lycopene and lutein/zeaxanthin were detected by HPLC. Unconditional logistic regression was used to estimate the odds ratio (OR) and 95% confidence internal (CI) after adjusting for various confounders. Serum levels of α-carotene, ß-cryptoxanthin and lycopene were found to be inversely associated with colorectal cancer risk. The adjusted ORs of the highest quartile relative to the lowest quartile serum level were 0.49 (95% CIs 0.33-0.72) for α-carotene, 0.44 (95% CIs 0.29-0.66) for ß-cryptoxanthin, and 0.36 (95% CIs 0.24-0.54) for lycopene, respectively. The association between serum ß-carotene, lutein/zeaxanthin and colorectal cancer risk was not statistically significant. CONCLUSION: The results indicated that the incidence of colorectal cancer was associated with lower serum levels of α-carotene, ß-cryptoxanthin and lycopene among Chinese population residing in Guangdong.

Nonalcoholic Fatty Liver Disease and Insulin Resistance: New Insights and Potential New Treatments.

Nonalcoholic fatty liver disease (NAFLD) is one of the most common chronic liver disorders worldwide. It is associated with clinical states such as obesity, insulin resistance, and type 2 diabetes, and covers a wide range of liver changes, ranging from simple steatosis to non-alcoholic steatohepatitis (NASH), liver cirrhosis, and hepatocellular carcinoma. Metabolic disorders, such as lipid accumulation, insulin resistance, and inflammation, have been implicated in the pathogenesis of NAFLD, but the underlying mechanisms, including those that drive disease progression, are not fully understood. Both innate and recruited immune cells mediate the development of insulin resistance and NASH. Therefore, modifying the polarization of resident and recruited macrophage/Kupffer cells is expected to lead to new therapeutic strategies in NAFLD. Oxidative stress is also pivotal for the progression of NASH, which has generated interest in carotenoids as potent micronutrient antioxidants in the treatment of NAFLD. In addition to their antioxidative function, carotenoids regulate macrophage/Kupffer cell polarization and thereby prevent NASH progression. In this review, we summarize the molecular mechanisms involved in the pathogenesis of NAFLD, including macrophage/Kupffer cell polarization, and disturbed hepatic function in NAFLD. We also discuss dietary antioxidants, such as ß-cryptoxanthin and astaxanthin, that may be effective in the prevention or treatment of NAFLD.

Higher intake of cryptoxanthin is related to low body mass index and body fat in Japanese middle-aged women.

OBJECTIVES: The prevalence of cardiovascular diseases increases with age, especially in postmenopausal women. In this study, we investigated the dietary patterns associated with body mass and body fat in Japanese middle-aged women. STUDY DESIGN: Cross-sectional. MAIN OUTCOME MEASURES: This study used baseline data collected in a previous study in 88 women aged 40-60 years. Participants were assessed for age, menopausal status, lifestyle factors, body composition, and dietary habits using a brief-type self-administered diet history questionnaire, which provides information on the amounts of nearly 100 nutritional factors consumed during the previous month. Classifying body mass index (BMI) as low (≤22kg/m2) or high (>22kg/m2) and percentage body fat as low (≤25%) or high (>25%), we sought to identify the nutritional factors associated with BMI and percentage body fat. RESULTS: Consumption differences between high/low BMI and high/low body fat percentage groups were not significant for any nutritional factors except cryptoxanthin. Multiple logistic regression analysis adjusting for age, menopausal status, working, exercise, and smoking revealed that higher cryptoxanthin intake was associated with low BMI (adjusted odds ratio, 1.22 per 100µg/day increase of cryptoxanthin intake; 95% confidence interval, 1.01-1.52) and low body fat percentage (adjusted odds ratio, 1.36 per 100µg/day increase of cryptoxanthin intake; 95% confidence interval, 1.13-1.70). CONCLUSIONS: Higher intake of cryptoxanthin was shown to be related to low body mass and body fat in Japanese middle-aged women.

Absorption, metabolism, and functions of ß-cryptoxanthin.

ß-Cryptoxanthin, a carotenoid found in fruits and vegetables such as tangerines, red peppers, and pumpkin, has several functions important for human health. Most evidence from observational, in vitro, animal model, and human studies suggests that ß-cryptoxanthin has relatively high bioavailability from its common food sources, to the extent that some ß-cryptoxanthin-rich foods might be equivalent to ß-carotene-rich foods as sources of retinol. ß-Cryptoxanthin is an antioxidant in vitro and appears to be associated with decreased risk of some cancers and degenerative diseases. In addition, many in vitro, animal model, and human studies suggest that ß-cryptoxanthin-rich foods may have an anabolic effect on bone and, thus, may help delay osteoporosis.

The Influence of Iron and Zinc Supplementation on the Bioavailability of Provitamin A Carotenoids from Papaya Following Consumption of a Vitamin A-Deficient Diet.

Iron deficiency anemia, zinc and vitamin A deficiencies are serious public health problems in Cameroon, as in many developing countries. Local vegetables which are sources of provitamin A carotenoids (PACs) can be used to improve vitamin A intakes. However, traditional meals are often unable to cover zinc and iron needs. The aim of this study was to determine the bioavailability of 3 PACs (α-carotene, ß-carotene, and ß-cryptoxanthin) in young men, who were fed with a vitamin A-free diet and received iron and zinc supplementation. Twelve healthy participants were divided into three groups and were supplemented with elemental iron (20 mg of iron fumarate), 20 mg of zinc sulfate or iron+zinc (20 mg of iron in the morning and 20 mg of zinc in the evening) for 11 d. They were given a vitamin A- and PAC-free diet from the 6th to the 11th day, followed by a test meal containing 0.55 kg of freshly peeled papaya as a source of PACs. Blood samples were collected four times successively on the 11th day (the test meal day), at T0 (just after the test meal), after 2 h (T2), after 4 h (T4) and after 7 h (T7). Ultracentrifugation was used to isolate serum chylomicrons. Retinol appearance and PAC postprandial concentrations were determined. The supplementation with zinc, iron and iron+zinc influenced the chylomicron appearance of retinol and PACs differently as reflected by retention times and maximum absorption peaks. Iron led to highest retinol levels in the chylomicron. Zinc and iron+zinc supplements were best for optimal intact appearance of α-carotene, ß-carotene and ß-cryptoxanthin respectively. Supplementation with iron led to the greatest bioavailability of PACs from papaya and its conversion to retinol.

ß-Cryptoxanthin Synergistically Enhances the Antitumoral Activity of Oxaliplatin through ΔNP73 Negative Regulation in Colon Cancer.

BACKGROUND: The acquired resistance to chemotherapy represents the major limitation in the treatment of cancer. New strategies to solve this failure and improve patients' outcomes are necessary. The cancer preventive effect of ß-cryptoxanthin has been widely described in population studies. Few reports support its putative use as an antitumoral compound. Here we focus on the therapeutic potential of ß-cryptoxanthin individually or in combination with oxaliplatin in colon cancer and try to decipher the molecular basis underlying its effect. METHODS: Apoptosis, viability and proliferation assays, mouse models, and an intervention study in 20 healthy subjects were performed. A PCR array was carried out to unravel the molecular putative basis of the ß-cryptoxanthin effect, and further signaling experiments were conducted. Comet Assay was completed to evaluate the genotoxicity of the treatments. RESULTS: ß-Cryptoxanthin differentially regulates the expression of the P73 variants in vitro, in vivo, and in a human intervention study. This carotenoid decreases the proliferation of cancer cells and cooperates with oxaliplatin to induce apoptosis through the negative regulation of ΔNP73. The antitumoral concentrations of oxaliplatin decrease in the presence of ß-cryptoxanthin to achieve same percentage of growth inhibition. The genotoxicity in peripheral blood mononuclear cells of mice decreased in the combined treatment. CONCLUSIONS: We propose a putative novel therapeutic strategy for the treatment of colon cancer based on the combination of ß-cryptoxanthin and oxaliplatin. The combined regimen produced more benefit than either individual modality without increasing side effects. In addition, the concentration-limiting toxicity of oxaliplatin is reduced in the presence of the carotenoid.

Multicarotenoids at Physiological Levels Inhibit Metastasis in Human Hepatocarcinoma SK-Hep-1 Cells.

Several studies have demonstrated that single carotenoid, including lycopene, ß-carotene, and α-carotene, exhibits antimetastatic effects; however, little is known whether multicarotenoids have similar effects. Herein, we investigated the antimetastatic effect of multicarotenoids at physiological serum levels in Taiwanese (MCT at 1.4 µM) and American (MCA at 1.8 µM) populations using human hepatocarcinoma SK-Hep-1 cells in comparison with single carotenoid, such as lycopene (0.3 or 0.6 µM, respectively), α-carotene (0.1 µM), ß-carotene (0.4 µM), lutein (0.4 or 0.5 µM, respectively), and ß-cryptoxanthin (0.2 µM). Results reveal that MCA treatment exhibited an additive inhibition on invasion, migration and adhesion at 24 and 48 h of incubation, whereas MCT treatment possessed additive inhibition at 48 h of incubation. The antimetastatic action of MCT and MCA involved additive reduction on activities of matrix metalloproteinase (MMP)-2, -9, and protein expression of Rho and Rac 1 but additive promotion on protein expression of tissue inhibitor of MMP (TIMP)-1 and -2. All of these effects were stronger in MCA than in MCT at 24 and 48 h of incubation. These results demonstrate that multi-carotenoids effectively inhibit metastasis of human hepatocarcinoma SK-Hep-1 cells. More in vivo studies are needed to confirm these findings.

Effect of kumquat (Fortunella crassifolia) pericarp on natural killer cell activity in vitro and in vivo.

Natural killer (NK) cells play a key role in innate immune defense against infectious disease and cancer. A reduction of NK activity is likely to be associated with increased risk of these types of disease. In this study, we investigate the activation potential of kumquat pericarp acetone fraction (KP-AF) on NK cells. It is shown to significantly increase IFN-γ production and NK cytotoxic activity in human KHYG-1 NK cells. Moreover, oral administration of KP-AF significantly improves both suppressed plasma IFN-γ levels and NK cytotoxic activity per splenocyte in restraint-stressed mice. These results indicate that raw kumquat pericarp activates NK cells in vitro and in vivo. To identify the active constituents, we also examined IFN-γ production on KHYG-1 cells by the predicted active components. Only ß-cryptoxanthin increased IFN-γ production, suggesting that NK cell activation effects of KP-AF may be caused by carotenoids such as ß-cryptoxanthin.

Prediction of fruit and vegetable intake from biomarkers using individual participant data of diet-controlled intervention studies.

Fruit and vegetable consumption produces changes in several biomarkers in blood. The present study aimed to examine the dose-response curve between fruit and vegetable consumption and carotenoid (α-carotene, ß-carotene, ß-cryptoxanthin, lycopene, lutein and zeaxanthin), folate and vitamin C concentrations. Furthermore, a prediction model of fruit and vegetable intake based on these biomarkers and subject characteristics (i.e. age, sex, BMI and smoking status) was established. Data from twelve diet-controlled intervention studies were obtained to develop a prediction model for fruit and vegetable intake (including and excluding fruit and vegetable juices). The study population in the present individual participant data meta-analysis consisted of 526 men and women. Carotenoid, folate and vitamin C concentrations showed a positive relationship with fruit and vegetable intake. Measures of performance for the prediction model were calculated using cross-validation. For the prediction model of fruit, vegetable and juice intake, the root mean squared error (RMSE) was 258.0 g, the correlation between observed and predicted intake was 0.78 and the mean difference between observed and predicted intake was - 1.7 g (limits of agreement: - 466.3, 462.8 g). For the prediction of fruit and vegetable intake (excluding juices), the RMSE was 201.1 g, the correlation was 0.65 and the mean bias was 2.4 g (limits of agreement: -368.2, 373.0 g). The prediction models which include the biomarkers and subject characteristics may be used to estimate average intake at the group level and to investigate the ranking of individuals with regard to their intake of fruit and vegetables when validating questionnaires that measure intake.

[ß-Cryptoxanthin and the risk for lifestyle-related disease: findings from recent nutritional epidemiologic studies].

  Antioxidant micronutrients, such as vitamins and carotenoids, exist in abundance in fruits and vegetables and have been known to contribute to the body's defense against reactive oxygen species. Numerous recent epidemiologic studies have demonstrated that a high dietary consumption of fruit and vegetables rich in carotenoids or with high serum carotenoid concentrations results in lower risks of certain cancers, diabetes, and cardiovascular disease. These epidemiologic studies have suggested that antioxidant carotenoids may have a protective effect against several lifestyle-related diseases. ß-Cryptoxanthin is a carotenoid pigment found in Japanese mandarin (Citrus unshiu MARC.) fruit, which is mainly produced in Japan. Our nutritional epidemiologic survey, the Mikkabi Study, utilized data derived from health examinations of inhabitants performed in the town of Mikkabi in Shizuoka, Japan. In this survey, we measured serum ß-cryptoxanthin as a specific biomarker to estimate the consumption of Japanese mandarin fruit. From the cross-sectional analyses from the Mikkabi Study, we found inverse associations of serum ß-cryptoxanthin with the risks for atherosclerosis, insulin resistance, liver dysfunction, metabolic syndrome, low bone mineral density, and oxidative stress. In this review, recent epidemiologic studies about the associations between serum ß-cryptoxanthin with the risk for several lifestyle-related diseases were reviewed.

Dietary intake of carotenoids and risk of type 2 diabetes.

BACKGROUND AND AIMS: Carotenoids may reduce diabetes risk, due to their antioxidant properties. However, the association between dietary carotenoids intake and type 2 diabetes risk is still unclear. Therefore, the objective of this study was to examine whether higher dietary carotenoid intakes associate with reduced type 2 diabetes risk. METHODS AND RESULTS: Data from 37,846 participants of the European Prospective Investigation into Cancer and Nutrition- Netherlands study were analyzed. Dietary intakes of ß-carotene, α-carotene, ß-cryptoxanthin, lycopene, lutein & zeaxanthin and the sum of these carotenoids were assessed using a validated food frequency questionnaire. Incident type 2 diabetes was mainly self-reported, and verified against general practitioner information. Mean ±SD total carotenoid intake was 10 ± 4 mg/day. During a mean ±SD follow-up of 10 ± 2 years, 915 incident cases of type 2 diabetes were ascertained. After adjustment for age, sex, diabetes risk factors, dietary intake, waist circumference and BMI, higher ß-carotene intakes associated inversely with diabetes risk [Hazard Ratio quartile 4 versus quartile 1 (HR(Q4)): 0.78 (95%CI:0.64,0.95), P-linear trend 0.01]. For α-carotene, a borderline significant reduced risk was observed, with a HR(Q4) of 0.85 (95%CI:0.70,1.03), and P-linear trend 0.05. ß-cryptoxanthin, lycopene, lutein & zeaxanthin, and the sum of all carotenoids did not associate with diabetes risk. CONCLUSIONS: This study shows that diets high in ß-carotene and α-carotene are associated with reduced type 2 diabetes in generally healthy men and women.

Prevention and reversal of lipotoxicity-induced hepatic insulin resistance and steatohepatitis in mice by an antioxidant carotenoid, ß-cryptoxanthin.

Excessive hepatic lipid accumulation promotes macrophages/Kupffer cells activation, resulting in exacerbation of insulin resistance and progression of nonalcoholic steatohepatitis (NASH). However, few promising treatment modalities target lipotoxicity-mediated hepatic activation/polarization of macrophages for NASH. Recent epidemiological surveys showed that serum ß-cryptoxanthin, an antioxidant carotenoid, was inversely associated with the risks of insulin resistance and liver dysfunction. In the present study, we first showed that ß-cryptoxanthin administration ameliorated hepatic steatosis in high-fat diet-induced obese mice. Next, we investigated the preventative and therapeutic effects of ß-cryptoxanthin using a lipotoxic model of NASH: mice fed a high-cholesterol and high-fat (CL) diet. After 12 weeks of CL diet feeding, ß-cryptoxanthin administration attenuated insulin resistance and excessive hepatic lipid accumulation and peroxidation, with increases in M1-type macrophages/Kupffer cells and activated stellate cells, and fibrosis in CL diet-induced NASH. Comprehensive gene expression analysis showed that ß-cryptoxanthin down-regulated macrophage activation signal-related genes significantly without affecting most lipid metabolism-related genes in the liver. Importantly, flow cytometry analysis revealed that, on a CL diet, ß-cryptoxanthin caused a predominance of M2 over M1 macrophage populations, in addition to reducing total hepatic macrophage and T-cell contents. In parallel, ß-cryptoxanthin decreased lipopolysaccharide-induced M1 marker mRNA expression in peritoneal macrophages, whereas it augmented IL-4-induced M2 marker mRNA expression, in a dose-dependent manner. Moreover, ß-cryptoxanthin reversed steatosis, inflammation, and fibrosis progression in preexisting NASH in mice. In conclusion, ß-cryptoxanthin prevents and reverses insulin resistance and steatohepatitis, at least in part, through an M2-dominant shift in macrophages/Kupffer cells in a lipotoxic model of NASH.

Antioxidant micronutrients and the risk of renal cell carcinoma in the Women's Health Initiative cohort.

BACKGROUND: Renal cell carcinoma (RCC) is the eighth leading cancer among women in incidence and commonly is diagnosed at a more advanced stage. Oxidative stress has been considered to play an important role in the pathogenesis of RCC. Various dietary micronutrients have antioxidant properties, including carotenoids and vitamins C and E; thus, diets rich in these nutrients have been evaluated in relation to RCC prevention. The objective of this study was to explore the correlation between antioxidant micronutrients and the risk of RCC. METHODS: In total, 96,196 postmenopausal women who enrolled in the Women's Health Initiative (WHI) between 1993 and 1998 and were followed through July 2013 were included in this analysis. Dietary micronutrient intake was estimated from the baseline WHI food frequency questionnaire, and data on supplement use were collected using an interview-based inventory procedure. RCC cases were ascertained from follow-up surveys and were centrally adjudicated. The risks for RCC associated with intake of α-carotene, ß-carotene, ß-cryptoxanthin, lutein plus zeaxanthin, lycopene, vitamin C, and vitamin E were analyzed using Cox proportional hazards regression adjusted for confounders. RESULTS: Two hundred forty women with RCC were identified during follow-up. Lycopene intake was inversely associated with RCC risk (P = .015); compared with the lowest quartile of lycopene intake, the highest quartile of intake was associated with a 39% lower risk of RCC (hazard ratio, 0.61; 95% confidence interval, 0.39-0.97). No other micronutrient was significantly associated with RCC risk. CONCLUSIONS: The current results suggest that further investigation into the correlation between lycopene intake and the risk of RCC is warranted.

Higher intake of carotenoid is associated with a lower risk of colorectal cancer in Chinese adults: a case-control study.

PURPOSE: The associations between specific carotenoid intake and colorectal cancer risk remain inconsistent. The aim of this study was to examine the association between specific dietary carotenoid intake with colorectal cancer risk in Chinese adults. METHOD: From July 2010 to October 2013, 845 eligible colorectal cancer cases and 845 frequency-matched controls (age and sex) completed in-person interviews. A validated food frequency questionnaire was used to estimate dietary intake. Multivariate logistical regression models were used to calculate the odds ratio (OR) and 95% confidence intervals (95% CIs) of colorectal cancer risk after adjusting for various confounders. RESULTS: A strong inverse association was found between ß-cryptoxanthin intake and colorectal cancer risk. Compared with the lowest quartile, the highest quartile intake showed a risk reduction of 77% (OR 0.23, 95% CI 0.17-0.33, P trend < 0.01) after adjustment for various confounding variables. The inverse associations were also observed for α-carotene (OR 0.50, 95% CI 0.37-0.68, P trend < 0.01), ß-carotene (OR 0.67, 95% CI 0.49-0.91, P trend < 0.01), and lycopene (OR 0.51, 95% CI 0.37-0.70, P trend < 0.01). There was no statistically significant association between lutein/zeaxanthin intake and colorectal cancer risk. These findings were consistent across cancer site, sources of controls, and smoking status. The inverse associations between dietary α-carotene, ß-cryptoxanthin, and lycopene intake and colorectal cancer risk were found in both males and females, while inverse associations between ß-carotene intake and colorectal cancer risk were only observed in males. CONCLUSIONS: Consumption of α-carotene, ß-carotene, ß-cryptoxanthin, and lycopene was inversely associated with colorectal cancer risk. No significant association was found between lutein/zeaxanthin intake and colorectal cancer risk.

Plasma carotenoids and retinol and overall and breast cancer risk: a nested case-control study.

Experimental studies suggest that carotenoids and retinol may play a role in carcinogenesis, but epidemiological evidence is lacking. We investigated the prospective associations between plasma concentrations of major carotenoids and retinol, and overall and breast cancer risk. A nested case-control study included all first incident cancer cases diagnosed in the SU.VI.MAX cohort between 1994 and 2002 (n = 159 cases, 1 matched control/case). Baseline plasma concentrations of carotenoids and retinol were measured by high-performance liquid chromatography. Conditional logistic regression was used to assess odds ratios for an increase of 0.1 µmol/L [odds ratio (OR)] and 95% confidence intervals (CI). Plasma ß-carotene (OR = 0.95, 95% CI = 0.90-0.99, Ptrend = 0.04) and ß-cryptoxanthin concentrations (OR = 0.89, 95% CI = 0.81-0.99, Ptrend = 0.03) were inversely associated with overall cancer risk. Plasma ß-cryptoxanthin concentration was inversely associated with breast cancer risk (OR = 0.83, 95% CI = 0.71-0.96, Ptrend = 0.02). The OR between plasma lycopene concentration and overall cancer risk was 1.07 (0.99-1.15), Ptrend = 0.06. This association turned significant (Ptrend = 0.01) when excluding cancer cases diagnosed during the first year of follow-up. This prospective study suggests an inverse association between plasma concentrations of ß-cryptoxanthin and both overall and breast cancer risk, and an inverse association between ß-carotene and overall cancer risk. The direct association between lycopene concentration and cancer risk deserves further investigation.

ß-Cryptoxanthin alleviates diet-induced nonalcoholic steatohepatitis by suppressing inflammatory gene expression in mice.

Recent nutritional epidemiological surveys showed that serum ß-cryptoxanthin inversely associates with the risks for insulin resistance and liver dysfunction. Consumption of ß-cryptoxanthin possibly prevents nonalcoholic steatohepatitis (NASH), which is suggested to be caused by insulin resistance and oxidative stress from nonalcoholic fatty liver disease. To evaluate the effect of ß-cryptoxanthin on diet-induced NASH, we fed a high-cholesterol and high-fat diet (CL diet) with or without 0.003% ß-cryptoxanthin to C56BL/6J mice for 12 weeks. After feeding, ß-cryptoxanthin attenuated fat accumulation, increases in Kupffer and activated stellate cells, and fibrosis in CL diet-induced NASH in the mice. Comprehensive gene expression analysis showed that although ß-cryptoxanthin histochemically reduced steatosis, it was more effective in inhibiting inflammatory gene expression change in NASH. ß-Cryptoxanthin reduced the alteration of expression of genes associated with cell death, inflammatory responses, infiltration and activation of macrophages and other leukocytes, quantity of T cells, and free radical scavenging. However, it showed little effect on the expression of genes related to cholesterol and other lipid metabolism. The expression of markers of M1 and M2 macrophages, T helper cells, and cytotoxic T cells was significantly induced in NASH and reduced by ß-cryptoxanthin. ß-Cryptoxanthin suppressed the expression of lipopolysaccharide (LPS)-inducible and/or TNFα-inducible genes in NASH. Increased levels of the oxidative stress marker thiobarbituric acid reactive substances (TBARS) were reduced by ß-cryptoxanthin in NASH. Thus, ß-cryptoxanthin suppresses inflammation and the resulting fibrosis probably by primarily suppressing the increase and activation of macrophages and other immune cells. Reducing oxidative stress is likely to be a major mechanism of inflammation and injury suppression in the livers of mice with NASH.

Certain carotenoids enhance the intracellular glutathione level in a murine cultured macrophage cell line by inducing glutamate-cysteine-ligase.

SCOPE: Glutathione (GSH) increases in RAW264 murine macrophage cells exposed to ß-carotene or ß-cryptoxanthin, however, the underlying mechanism has not been clarified. In the present study, we investigated the expression of glutamate-cysteine-ligase (GCL), the rate-limiting enzyme in GSH synthesis, in these cells. METHODS AND RESULTS: Both the protein and mRNA expression of GCL increased in a ß-carotene concentration-dependent manner. Buthionine sulfoximine, a GCL inhibitor, abolished the ß-carotene-induced GSH increase without affecting the ß-carotene-induced GCL protein expression. Both cycloheximide, a translation inhibitor, and actinomycin D, a transcription inhibitor, completely suppressed the ß-carotene-induced GCL protein expression and the concomitant GSH increase. Actinomycin D inhibited the ß-carotene-induced Gcl mRNA expression as well. Similarly to ß-carotene, ß-cryptoxanthin upregulated the GCL protein expression, but lutein did not. The c-Jun N-terminal kinase (JNK) inhibitor, SP600125, suppressed the ß-carotene-induced GSH increase, whereas a p38 mitogen-activated protein kinase inhibitor or an extracellular signal-regulated kinase 1/2 inhibitor did not. The JNK inhibitor also suppressed the ß-carotene-induced GCL protein expression, and consistently ß-carotene induced JNK phosphorylation. CONCLUSION: These findings revealed that certain carotenoids induce the Gcl mRNA expression in RAW264 cells and subsequently the GCL protein expression, which concomitantly enhances the intracellular GSH level, in a JNK pathway-related manner.

Serum carotenoid levels and risk of lung cancer death in US adults.

Lung cancer is one of the most common cancers worldwide and is the leading cause of cancer-induced death in the USA. Although much attention has been focused on the anti-carcinogenic effect of consuming carotenoid-containing food or supplements, the results have been inconsistent. We investigated whether serum carotenoid levels were associated with the mortality risk of lung cancer in US adults using data from a nationally representative sample. The data were obtained from the Third Nutrition and Health Examination Survey (NHANES III) database and the NHANES III Linked Mortality File. A total of 10,382 participants aged over 20,years with available serum carotenoid levels and no other missing information on questionnaires and biomarkers at baseline (NHANES III) were included in the present study. Of the 10,382 participants, 161 subjects died due to lung cancer. We found that high serum levels of alpha-carotene and beta-cryptoxanthin at baseline were significantly associated with a lower risk of lung cancer death. When we stratified the risk by current smoking status, the risk of death of current smokers was significantly decreased to 46% (95% confidence interval, 31-94%) for alpha-carotene and 61% (95% confidence interval, 19-80%) for beta-cryptoxanthin. By contrast, no association was observed among never/former smokers at baseline. High serum levels of alpha-carotene and beta-cryptoxanthin are associated with a lower risk of lung cancer death in US adults.

Specific carotenoid intake is inversely associated with the risk of breast cancer among Chinese women.

The protective effect of dietary carotenoid intake on the risk of breast cancer is inconclusive. Moreover, data on dietary carotenoids in relation to breast cancer in non-Western populations are scarce. The aim of the present study was to examine the association between dietary carotenoid intake and the risk of breast cancer among Chinese women. A total of 561 cases and 561 controls who were frequency matched by age (5-year interval) and residence were recruited in the present case-control study. Dietary intake information was collected by a face-to-face interview using a validated FFQ. The OR and 95 % CI were assessed by multivariate logistic regression after adjusting for various potential confounders. An inverse association was observed between the consumption of α-carotene, ß-carotene, ß-cryptoxanthin and lutein/zeaxanthin and the risk of breast cancer. The multivariate-adjusted OR for the highest quartile of intake compared with the lowest quartile of intake were 0·61 (95 % CI 0·43, 0·88) for α-carotene, 0·54 (95 % CI 0·38, 0·78) for ß-carotene, 0·38 (95 % CI 0·26, 0·52) for ß-cryptoxanthin and 0·49 (95 % CI 0·34, 0·71) for lutein/zeaxanthin. Lycopene intake was not found to be associated with the risk of breast cancer, with the adjusted OR of 0·89 (95 % CI 0·61, 1·30). These inverse associations were more evident among pre-menopausal women and women who were exposed to second-hand smoke. The protective effect of specific carotenoid intake was observed for all subtypes of hormone receptor status of breast cancer. The present study indicated that a greater intake of specific carotenoids was associated with a decreased risk of breast cancer among Chinese women residing in Guangdong.