Progress 04/01/17 to 03/31/20
Outputs
Target Audience:Consumers, particularly people with obesity and high sugar consumption, will benefit from the potential health benefits of sweet red pepper and red pepper products, and from knowledge of BCX as a dietary biological active component. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?The project has provided an ideal training environment for PhD students of Tufts School of Nutrition. This project helped greatly two PH.D. graduate students to understand how dietary components and molecular pathways can influence inflammation and chronic disease development. This project utilizing biochemistry and molecular biology techniques assisted these two students to become research scientists in the field of nutrition and chronic disease prevention. How have the results been disseminated to communities of interest?Nationally, we have reported our finding as abstracts at the American Society of Nutrition (ASN) annual meeting (2018, 2019 and 2020 as an e-poster), at the 11th Gordon Research Conference on Carotenoids (2018); and at the 256th American Chemical Society annual meeting (2018). Internationally, we presented "Vitamin A independent biological function of β-cryptoxanthin: Implications for chronic disease prevention" at the 5th International vitamin Conference, Sydney, Australia (2019); "Phytochemical carotenoids and chronic disease prevention" at the International conference on Oncology, Zhengzhou, China (2019), and "Function of carotenoid β-cryptoxanthin: Implications for cancer prevention" at the International conference on food and Nutrition, Kobe, Japan (2019). We have published 9 manuscripts and 3 manuscripts (accepted or in revision) generated from the project. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
The prevalence of non-alcoholic fatty liver disease (NAFLD) is positively associated with the obesity epidemic and the risks for hepatocellular carcinoma (HCC), which is on the rise in the United States, where it continues to increase both in incidence and death rate. We investigated the role of provitamin A carotenoid, β-cryptoxanthin (BCX), in sweet red pepper and its products in preventing high refined carbohydrate (HRCD)/sugar-related inflammation, NAFLD and HCC. We addressed the molecular mechanisms of BCX protection in the presence or absence of carotenoid cleavage enzymes (BCO1 and BCO2 to generating vitamin A). In support of Objective 1 and 2, we have successfully completed the following projects: Project 1: Ablation of carotenoid cleavage enzymes (BCO1 and BCO2) induced NAFLD by altering FXR/miR-34a/SIRT1 pathway.Wild type mice (WT) and BCO1/BCO2 double knockout mice (BCO1/BCO2 DKO) were fed standard rodent chow diet for 24 weeks. All BCO1/BCO2 DKO mice developed liver steatosis and had significantly higher levels of triglyceride and total cholesterol levels in the liver and plasma compared to WT. These hepatic changes in the BCO1/BCO2 DKO mice were associated with significant: 1) decreases in nuclear protein levels of farnesoid X receptor (FXR), and mRNA levels of FXR, small heterodimer partner, and sirtuin 1 (SIRT1); 2) alterations to the microRNAs (miR-34a, miR-33, miR-122) related to triglyceride accumulation and cholesterol metabolism; and 3) increases in hepatic oxidative stress markers (HO-1, SOD1, SOD2, GPX, catalase) and mRNA and protein levels of lipogenesis markers. The present study provided novel experimental evidence that the ablation of both BCO1/BCO2 led to the development of NAFLD, indicating that BCO1/BCO2 could play a significant role in maintaining normal hepatic lipid and cholesterol homeostasis, potentially through the activation of the FXR/miR-34a/SIRT1 pathway. Project 2: β-Cryptoxanthin alleviates high-refined-carbohydrate diet (HRCD)-induced NAFLD by regulating SIRT1 independent of carotenoid cleavage enzymes.BCO1/BCO2 DKO mice and WT mice were randomly assigned to either the HRCD (66.5 % of energy as carbohydrate including sucrose and maltodextrin) or the HRCD with BCX feeding for 24 weeks. The dose of BCX (10 mg BCX/kg diet, paprika extract rich in 11% BCX) was equivalent to that on daily human consumption of 3-4 ounces of a sweet red pepper. We found that hepatic levels of BCX, but not vitamin A (retinol and retinyl palmitate), were significantly higher (33-fold) in the DKO mice than in the WT mice. BCX feeding significantly reduced hepatic steatosis score in both WT and BCO1/BCO2 DKO mice compared to their respective HRCD counterparts. Moreover, BCX feeding significantly reduced hepatic concentrations of triglyceride and total cholesterol levels in BCO1/BCO2 DKO mice, compared to the corresponding HRCD group. These hepatic changes by BCX feeding were related to the significant upregulation of mRNA and protein levels of nicotinamide phosphoribosyltransferase (NAMPT) and SIRT1, downregulation of mRNA levels of the cholesterol biosynthesis marker (HMG-CoAR) and lipogenesis markers (SREBP-1C, ACC, FAS), and increases in mRNA levels of the fatty acid β-oxidation marker. In mesenteric adipose tissue, BCX significantly down-regulated the inflammatory cytokine IL-6 and up-regulated Sirt1 and fatty acid β-oxidation marker Acox1 and in DKO mice but significantly suppressed lipogenesis marker Acc1 in WT mice. The present study provided compelling experimental evidence that 1) BCX has protective effects against HRCD-induced NAFLD potentially by regulating NAMPT/SIRT1 pathway independent of carotenoid cleavage enzymes; and 2) the protective effects of dietary BCX are achieved through different molecular mechanisms in the liver-mesenteric adipose tissue axis. Project 3: Ablation of systemic SIRT1 activity suppressed high-refined carbohydrate diet (HRCD)-promoted hepatocellular carcinoma by increased acetylated-p53.Male and female SIRT1 homozygous mice deleted the catalytic activity (Sirt1Y/Y) from C57/BL6J background and respective wild type (WT) mice were injected intraperitoneally with a liver-specific carcinogen, diethylnitrosamine (DEN), and fed a HRCD for 24 weeks. We observed that female WT mice developed tumors in the liver (37.5%), but none of Sirt1Y/Y mice developed tumors in the liver. In male mice, all WT and Sirt1Y/Y mice developed liver tumors. However, Sirt1Y/Y mice exhibited significant decreased tumor numbers and tumor volume in the liver compared to the respective WT mice. The reduction in liver tumor number and tumor volume was associated with significant increased protein levels of acetylated-p53 and its downstream target, p27 in the livers of Sirt1Y/Y compared with WT mice. Moreover, Sirt1Y/Y mice showed significant decreased protein levels of cyclin D1 and anti-apoptotic marker Bcl-2. Fatty acid β-oxidation markers (CPT1, UCP1, UCP3) were significantly increased in Sirt1Y/Y compared with WT mice. The study suggests that SIRT1 can function differently in HCC tumors compared to corresponding normal hepatic tissues. SIRT1 activity may arise as a result of being "hijacked" by tumor cells, thereby promoting HCC development by reducing acetylated-p53, which can contribute to the reduction of fatty acid β-oxidation and promoting cell senescence. Project 4: Xanthophyll β-cryptoxanthin inhibits high-refined carbohydrate diet-promoted liver cancer progression in mice.Two-week-old male wild-type (WT) and BCO1-/-/BCO2-/- double knock-out (DKO) mice were given a single intraperitoneal injection of DEN (25 mg/kg body weight) to initiate hepatic carcinogenesis. At six weeks of age, all animals were fed HRCD with or without BCX (10 mg/kg diet) for 24 weeks. BCX feeding increased hepatic vitamin A levels in WT mice, but not in DKO mice that showed a significant accumulation of hepatic BCX. Compared to their respective HRCD littermates, both WT and DKO fed BCX had significantly lower HCC multiplicity (58-60%), average tumor size (21-24%), and total tumor volume (51-58%), and the steatosis scores. The chemopreventive effects of BCX were associated with increased p53 protein acetylation and gluconeogenesis markers (phosphoenolpyruvate carboxykinase, glucose 6-phosphatase) and decreased protein levels of a glycolysis marker (lactate dehydrogenase) and of the hypoxia-inducible factor-1α and its downstream targets, matrix metalloproteinase 2/9 in tumors. We concluded that the BCX feeding may alleviate HRCD-promoted HCC progression by modulating the acetylation of p53, hypoxic tumor microenvironment and glucose metabolism, independent of BCO1 and BCO2. In summary, through this work, we have achieved our goal by demonstrating that dietary BCX feeding inhibits high refined carbohydrate/sugar diet-promoted NAFLD and HCC development. The protective effect of BCX is effective in the presence or absence of carotenoid cleavage enzymes (BCO1 and BCO2), indicating that the BCX molecule itself has a unique biological function without generating vitamin A. This was also supported by dietary BCX, which is effective against HRCD-promoted HCC progression, and was associated with increased tumor suppressor p53 function and decreased glucose metabolism in tumors. These studies provided valuable insights into the mechanisms underlying the beneficial effect of BCX from sweet red peppers against NALFD and HCC development. Although BCO1/BCO2 polymorphisms have been associated with variations in the status of human and animal carotenoid levels, we believe that consumers, particularly people with obesity and high sugar consumption, would benefit from the health benefits of sweet red pepper and red pepper products, and from knowledge of BCX as a dietary bioactive component against NAFLD and HCC development.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
Xia H, Liu C, Li CC, Fu M, Hu KQ, Aizawa K, Hiroyuki S. Zhao LP, Wang X-D. Dietary tomato powder inhibits high fat diet-promoted hepatocellular carcinoma with alteration of gut microbiota in mice lacking carotenoid cleavage enzymes. Cancer Prev Res (Phila). 11, 797-810, 2018
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
Li CC, Liu C, Fu M, Hu KQ, Aizawa K, Cheng J, von Lintig J, Wang X-D. Tomato powder inhibits hepatic steatosis and inflammation potentially through restoring SIRT1 activity and adiponectin function independent of carotenoid cleavage enzymes in mice. Mol Nutr Food Res. 62(8):1700738, 2018
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
Cheng C, Miao B, Hu KQ, Fu X and Wang X-D. Apo-10-lycopenoic acid inhibits cancer cell migration and angiogenesis and induces peroxisome proliferator-activated receptor gamma. Journal Nutritional Biochemistry 56, 26-34, 2018
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
Lim JY, Liu C, Hu KQ, Smith DE, Wang X-D. Ablation of carotenoid cleavage enzymes (BCO1 and BCO2) induced hepatic steatosis by altering the farnesoid X receptor/miR-34a/sirtuin 1 pathway. Arch Biochem. Biophys. 654: 1-9, 2018
- Type:
Journal Articles
Status:
Published
Year Published:
2019
Citation:
Lim JY, Liu C, Hu KQ, Smith DE, Wu D, Lamon-Fava S, Ausman LM, Wang XD. Dietary beta-cryptoxanthin prevents inhibits high-refined carbohydrate diet-induced fatty liver via differential protective mechanisms depending on carotenoid cleavage enzymes in male mice. J Nutr. 149: 15531564, 2019
- Type:
Journal Articles
Status:
Published
Year Published:
2019
Citation:
Rakica JM, Liu C, Veeramachaneni S, Wu D, Pauld L, Chen O, Ausman LM, Wang XD. Lycopene inhibits cigarette smoke-induced chronic obstructive pulmonary disease and lung carcinogenesis via modulation of reverse cholesterol transport in ferrets. Cancer Prevention Research 12: 421-432, 2019.
- Type:
Journal Articles
Status:
Published
Year Published:
2020
Citation:
Lim JY and Wang XD. Mechanistic understanding of beta-cryptoxanthin and lycopene in cancer prevention in animal models. Biochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids. (Accepted, e-pub ahead of print), 2020
- Type:
Journal Articles
Status:
Published
Year Published:
2020
Citation:
Rakica JM and Wang XD. Role of lycopene in smoke-promoted chronic obstructive pulmonary disease and lung carcinogenesis. Archives of Biochemistry and Biophysics (accepted, e-pub ahead of print) 2020
- Type:
Journal Articles
Status:
Published
Year Published:
2020
Citation:
Lim JY, Liu C, Hu KQ, Smith DE, Wu D, Lamon-Fava S, Ausman LM, Wang XD. Dietary beta-cryptoxanthin prevents inhibits high-refined carbohydrate diet-promoted hepatocellular carcinoma in mice. Mol Nutr Food Res. (Accepted, e-pub ahead of print), 2020
- Type:
Journal Articles
Status:
Accepted
Year Published:
2020
Citation:
Liu C, Rafacho B, and Wang X-D. Xanthophyll beta-cryptoxanthin treatment inhibits hepatic steatosis without altering vitamin A status in beta-carotene 910-oxygenase knockout mice. HBSN (accepted) 2020
- Type:
Journal Articles
Status:
Under Review
Year Published:
2020
Citation:
Rakica JM, Liu C, Veeramachaneni S, Wu D, Paul L, Chen O, Ausman LM, Wang X-D. Dietary lycopene attenuates smoke-promoted nonalcoholic steatohepatitis by preventing suppression of antioxidant enzymes in ferrets. J. Nutritional Biochemistry (in revision).
- Type:
Journal Articles
Status:
Under Review
Year Published:
2020
Citation:
Chiaverelli RA, Liu C, Hu KQ, Lim JY, von Lintig J, Wang X-D. Intact beta-cryptoxanthin prevents lung inflammation independent of carotenoid cleavage enzymes. J. Nutritional Biochemistry (in revision).
|
Progress 04/01/18 to 03/31/19
Outputs
Target Audience:Consumers, particularly people with obesity and high sugar consumption, will benefit from the potential health benefits of sweet red pepper and red pepper products (e.g., paprika), and from knowledge of beta-cryptoxanthin as a dietary biological active component. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?The project greatly helped the graduate students understand how dietary components (high sugar diet) and genetic factors (carotenoid cleavage enzymes and sirtuins) can influence inflammation and chronic disease development. It provided an ideal training environment for PhD students of Tufts School of Nutrition, and visiting scientists. This project utilizing biochemistry and molecular biology techniques both in vivo and in vitro will assist graduate students and postdoctoral scholars to become research scientist in the field of nutrition and chronic disease prevention. How have the results been disseminated to communities of interest?We presented our research findings in the 2018 American Nutrition Society meeting, the 2018 NIFA/AFRI project director meeting and the 2018 Gordon Research conference on Carotenoids. We have published 4 manuscripts and submitted 2 manuscripts for publication. We will present our new research findings in the 2019 NIFA/AFRI project director meeting and in the 2019 American Nutrition Society meeting. What do you plan to do during the next reporting period to accomplish the goals?1) We will complete an intervention study with purified BCX on HRCD-promoted liver cancer in both WT and BCO1-/-/BCO2-/- double knockout mice; 2) We will continue to examine molecular targets and mechanisms for preventing HRCD-induced inflammation by BCX feeding in mice; 3) We will complete an intervention study of BCX and SRPE on liver cancer in sirt1+/+ WT, sirt1+/y heterozygous, and sirt1y/y homozygous mice; and 4) We will submit 2-3 manuscripts generated from the project for publication.
Impacts
What was accomplished under these goals?
In the past year (2018-2019), we investigated the role of bioactive components (e.g., β-cryptoxanthin (BCX)) in sweet red pepper and its products in preventing high refined carbohydrate (HRCD)/sugar-related inflammation and non-alcoholic fatty liver disease (NAFLD). Our investigation provided evidence that dietary BCX effectively prevents the development of HRCD-induced NAFLD in both the presence and absence of carotenoid cleavage enzymes (called BCO1 and BCO2 producing vitamin A and other metabolites). Notably, our data suggest that the mechanisms involved are different, indicating that the BCX molecule, when not cleaved, exerts independent functions. There were no significant differences in the liver levels of vitamin A between the groups, implying that intact BCX has unique roles in the prevention of HRCD-induced NAFLD, without generating vitamin A. Additionally, we observed that the protective effects of BCX against NAFLD are achieved through different molecular mechanisms in the liver-adipose tissue axis. Implications: BCX-induced mitigation of fatty liver in the absence of BCO1/BCO2 suggests that intact dietary BCX plays a role in the prevention of NAFLD. Although BCO1/BCO2 polymorphisms have been associated with variations in the status of human and animal carotenoid levels, we believe that consumers, particularly people with obesity and high sugar consumption, would benefit from the health benefits of sweet red pepper and red pepper products, and from knowledge of BCX as a dietary bioactive component. Study 1: Beta-Cryptoxanthin prevents non-alcoholic fatty liver disease through different mechanisms in the presence or absence of carotenoid cleavage enzymes in male mice β-Cryptoxanthin (BCX), a provitamin A carotenoid, is cleaved by carotenoid cleavage enzymes including β-carotene-15, 15'-oxygenase (BCO1) to generate vitamin A, and β-carotene-9', 10'-oxygenase (BCO2) which yields bioactive apo-carotenoids. Dietary supplementation of BCX can prevent non-alcoholic fatty liver disease (NAFLD), which is the most common chronic liver disease worldwide. We investigated whether BCX-mediated protection against NAFLD proceeds through the liver-mesenteric adipose tissue axis depending on the presence or absence of BCO1/BCO2. Six-week-old male wild type (WT) mice (n=30) and congenic BCO1-/-/BCO2-/- double KO (DKO) mice (n=30) were randomly fed either a high-refined carbohydrate diet (HRCD, 66.5% CHO) or HRCD with BCX (10 mg/kg diet) for 24 weeks. Results showed that hepatic levels of BCX, but not retinol and retinyl palmitate, were significantly (P < 0.001) higher (33-fold) in the DKO mice than in the WT mice. BCX significantly reduced hepatic steatosis and total cholesterol levels in both WT and DKO mice in comparison with their HRCD counterparts (P < 0.01 and P < 0.001, respectively), albeit through different mechanisms. In the liver, BCX significantly (P < 0.05) down-regulated mRNA for cholesterol synthesis genes Hmgcr and Hmgs1 and nuclear bile acid receptor Fxr, and up-regulated cholesterol catabolism gene Cyp7a1 in DKO mice in comparison with their HRCD counterparts. Furthermore, BCX significantly (P < 0.05) up-regulated antioxidant enzymes Sod1 and Cat in DKO mice in comparison with HRCD littermates. In WT mice, BCX significantly (P < 0.05) up-regulated hepatic mRNA for cholesterol efflux gene Abcg5 and nuclear receptor small heterodimer partner Shp in comparison with their HRCD counterparts. In mesenteric adipose tissue, BCX significantly down-regulated (P < 0.05) the inflammatory cytokine Il6 and up-regulated fatty acid β-oxidation marker Acox1 and Sirt1 in DKO mice but significantly (P < 0.05) suppressed lipogenesis marker Acc1 in WT mice. We concluded that the protective effects of dietary BCX against HRCD-induced NAFLD are achieved through different molecular mechanisms in the liver-mesenteric adipose tissue axis and depend on the carotenoid cleavage enzymes. Study 2: Intact beta-cryptoxanthin prevents inflammation independent of carotenoid cleavage enzymes We investigated intact BCX protective effects against cigarette smoke (CS) induced-lung inflammation, independent of BCO1/BCO2. BCO1-/-/BCO2-/- double knockout mice (DKO) and wild type (WT) mice with full expression of BCO1/BCO2, fed BCX (20 mg/kg diet), exposed to CS, resulted in significantly decreased neutrophil and macrophage infiltration, percentage of bronchiolar membranes with hyperplastic epithelium, and average distance between alveolated airspaces (Lm) in lung tissue, with no genotype or sex differences, compared to mice with CS-exposure alone. Furthermore, we found that the inflammatory lung lesion development was associated with decreased IL-6 and TNF-α and matrix metalloproteinases mRNA expression, respectively, in lung tissue, again without sex differences. By HPLC analysis, in WT mice, hepatic BCX was detected with a significant increase in hepatic retinol without change in retinyl ester concentration with BCX feeding. In DKO mice, BCX feeding significantly accumulated hepatic BCX with no change in retinol or retinyl ester concentration, compared with control diet-fed mice. In vitro, BCX and BCX metabolite, 3-OH-β-apo-10'-carotenal (3OH-BA10C), pretreatment inhibited lipopolysaccharide-induced mRNA expression of IL-6 and TNF-α and pAKT dose-dependently (1 to 4 µM) in human bronchial epithelial cell line, BEAS-2B, at comparable doses. This study demonstrates that BCX, either intact, independent of carotenoid cleavage enzymes, is an anti-inflammatory agent, preventing CS-induced lung inflammation and lesions. Study 3 Ablation of sirtuin 1 deacetylase activity induces cellular senescence and disrupts circadian clock in mice Sirtuin 1 (SIRT1), a NAD+-dependent protein/histone deacetylase has the capability to extend life span, delay aging, and prevent aging-related diseases. There are several reports showing that there is no significant decline in the SIRT1 protein with age, indicating that SIRT1 protein levels alone may not reflect deacetylase activity. We investigated the causal effect of systemic ablation of SIRT1 deacetylase activity on aging-related pulmonary disease development in mice. We used Sirt1y/y homozygous male mice carrying a point mutation (H355Y) that ablates the deacetylase activity, along with their wild type littermates (Sirt1+/+), and followed them for 6, 10 and 18 months of age. Results showed that Sirt1y/y homozygous mice developed severe pulmonary emphysema at the ages of 6, 10 and 18 months, with the respective incidences of 33%, 100% and 100%, while the Sirt1+/+ wild-type mice only developed emphysema (13% incidence) at 18 months of age. The development of emphysema in Sirt1y/y mice was accompanied with higher protein levels of matrix metalloproteinase (MMP)-2, MMP9, and tissue inhibitor of metalloproteinase-1, and ratio of cleaved/total anti-poly (ADP-ribose) polymerase. The ablation of SIRT1 activity significantly up-regulated mRNA expression of hypoxia-inducible factor-1α and retinoic acid receptor-beta, while p21 protein and phosphorylated AMPK increased and phosphorylated ribosomal S6 decreased, suggesting the association of ablation of SIRT1 activity with cellular quiescence and senescence. Additionally, the lack of SIRT1 activity down-regulated the mRNA expression of circadian clock genes (BMAL1, NPAS2, CRY1, CRY2) in the lungs of Sirt1y/y mice, as compared with that of Sirt1+/+ mice. There were no inflammatory responses in the lungs (e.g., inflammatory cell infiltrations, mRNA expressions of IL-6 and TNFα) in Sirt1y/y homozygous mice compared to Sirt1+/+ mice. In the present study, we demonstrated that the lacking of SIRT1 enzymatic activity plays a major role in the susceptibility of organs to aging and pulmonary emphysema development by inducing cellular senescence and disrupting circadian clock genes.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
Lim JY, Liu C, Hu KQ, Smith DE, Wang X-D. Ablation of carotenoid cleavage enzymes (BCO1 and BCO2) induced hepatic steatosis by altering the farnesoid X receptor/miR-34a/sirtuin 1 pathway. Arch Biochem. Biophys. 654: 1-9, 2018
- Type:
Journal Articles
Status:
Submitted
Year Published:
2019
Citation:
Lim JY, Liu C, Hu KQ, Smith DE, Wu D, Lamon-Fava S, Ausman LM, Wang X-D. ?-Cryptoxanthin alleviates high-refined-carbohydrate diet-induced through differential protective mechanisms depending on carotenoid cleavage enzymes in male mice. J. Nutrition (Submitted).
- Type:
Conference Papers and Presentations
Status:
Submitted
Year Published:
2019
Citation:
?-Cryptoxanthin prevents non-alcoholic fatty liver disease through different mechanisms depending on the presence or absence of carotenoid cleavage enzymes.Ji Ye Lim, Ch un Liu, Kang-Quan Hu, Donald E. Smith, Dayong Wu, Stefania Lamon-Fava, Lynne M. Ausman, Xiang-Dong Wang
- Type:
Conference Papers and Presentations
Status:
Submitted
Year Published:
2019
Citation:
Ablation of sirtuin 1 deacetylase activity induces pulmonary emphysema by inducing cellular senescence and disrupting circadian clock in mice.
Kang-Quan Hu, Hui Xia, Chun Liu, Michael W. McBurney, Xiang-Dong Wang
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
Cheng C, Mioao B, Hu KQ, Fu X and Wang X-D. Apo-10-lycopenoic acid inhibits cancer cell migration and angiogenesis and induces peroxisome proliferator-activated receptor ?. Journal Nutritional Biochemistry 56, 26-34, 2018.
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
Li CC, Liu C, Fu M, Hu KQ, Aizawa K, Cheng J, von Lintig J, Wang X-D. Tomato powder inhibits hepatic steatosis and inflammation potentially through restoring SIRT1 activity and adiponectin function independent of carotenoid cleavage enzymes in mice. Mol Nutr Food Res. 62(8):1700738, 2018
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
Xia H, Liu C, Li CC, Fu M, Hu KQ, Aizawa K, Hiroyuki S. Zhao LP, Wang X-D. Dietary tomato powder inhibits high fat diet-promoted hepatocellular carcinoma with alteration of gut microbiota in mice lacking carotenoid cleavage enzymes. Cancer Prev Res (Phila). 11, 797-810, 2018
- Type:
Journal Articles
Status:
Under Review
Year Published:
2019
Citation:
Chiaverelli RA, Liu C, Hu KQ, von Lintig J, Wang X-D. Intact ?-cryptoxanthin prevents lung inflammation independent of carotenoid cleavage enzymes. J. Nutritional Biochemistry (in revision).
|
Progress 04/01/17 to 03/31/18
Outputs
Target Audience:Consumers, particularly people (both adults and children) with obesity and high sugar consumption, will benefit from the potential health benefits of sweet red pepper and red pepper products, and nutrition scientists will benefit from knowledge of functionality of BCX as a dietary component. Farmers of these vegetables (sweet red pepper, butternut squash, and pumpkins) and fruits (tangerines and oranges) will benefit commercially and economically as well. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?The project provides an ideal training environment for PhD students of Tufts School of Nutrition. This project helped greatly the graduate student on the project to understand how dietary components (high sugar diet) and genetic factors (carotenoid cleavage enzymes) can influence inflammation and fatty liver disease development. This project utilizing biochemistry and molecular biology techniques will assist graduate students to become research scientist in the field of nutrition and chronic disease prevention. How have the results been disseminated to communities of interest?We will report our research findings at the upcoming 2018 American Nutrition Society meeting and the 2018 Gordon Research conference on Carotenoids. We have submitted a manuscript generated from the project. What do you plan to do during the next reporting period to accomplish the goals?1) We will conduct an intervention study with BCX and SRPE on HRCD-promoted hepatic cellular carcinoma (HCC) in both WT and BCO1-/-/BCO2-/- double knockout mice with a very low dose of carcinogen (DEN 25 mg/kg body weight in saline for initiation of tumorigenesis); 2) We will examine molecular targets and mechanisms for preventing HRCD-promoted tumorigenesis by BCX and SRPE feeding in mice; 3) We will conduct an intervention study of BCX and SRPE on hepatic carcinogenesis in sirt1+/+ WT, sirt1+/y heterozygous, and sirt1y/y homozygous mice; and 4) We will determine SIRT1 as a molecular target for BCX and SRPE preventing fatty liver diseases and HCC development.
Impacts
What was accomplished under these goals?
Study 1: Ablation of carotenoid cleavage enzymes (BCO1 and BCO2) induced NAFLD by altering FXR/miR-34a/SIRT1 pathway in mice Non-alcoholic fatty liver disease (NAFLD) is the most commonly occurring chronic liver disease worldwide. Both genetic and environmental factors are related to susceptibility to NAFLD. β-Carotene-15, 15'-oxygenase (BCO1) and β-carotene-9', 10'-oxygenase (BCO2) are essential enzymes in carotenoid metabolism. While BCO1/BCO2 polymorphisms have been associated with alterations to human and animal carotenoid levels, recent studies have suggested that BCO1 or BCO2 may have specific functions beyond the cleavage of carotenoids. In the present study, we investigated the effect of ablation of both BCO1/BCO2 in the development of NAFLD and its underlying molecular mechanism(s). Wild type mice (WT, n=8) and BCO1/BCO2 double knockout mice (BCO1/BCO2 DKO, n=8) of a C57BL/6J genetic background, were fed standard rodent chow diet for 24 weeks. (Results) There were no changes in body weight or liver weights between WT and BCO1/BCO2 DKO groups. However, all BCO1/BCO2 DKO mice developed liver steatosis (8/8) and had significantly higher levels of hepatic triglyceride and total cholesterol levels in the liver and plasma compared to WT (0/8, P < 0.05). These hepatic changes in the BCO1/BCO2 DKO mice were associated with significant: 1) increases in mRNA and protein levels of lipogenesis markers (SCD1, ACC, CD36), and decreases in the gene expressions of fatty acid β-oxidation markers (CPT-1, SIRT3, PPARα); 2) upregulation of the cholesterol metabolism markers (CYP7A1, CYP8B1, HMG-CoAR); 3) alterations to the microRNAs (miR-34a, miR-33, miR-122) related to TG accumulation and cholesterol metabolism; 4) increases in hepatic oxidative stress markers (HO-1, SOD1, SOD2, GPX, catalase); and 5) decreases in nuclear protein levels of farnesoid X receptor (FXR), and mRNA levels of FXR, small heterodimer partner (SHP), and sirtuin 1 (SIRT1). Taken together, the present study provided novel experimental evidence that the ablation of both BCO1/BCO2 led to the development of NAFLD, indicating that BCO1/BCO2 could play a significant role in maintaining normal hepatic lipid and cholesterol homeostasis, potentially through the activation of the FXR/miR-34a/SIRT1 pathway. Study 2 β-Cryptoxanthin alleviates high-refined-carbohydrate diet-induced NAFLD by regulating NAMPT/SIRT1 independent of carotenoid cleavage enzymes in mice. We have previously reported that a high-refined carbohydrate diet (HRCD) is more likely to contribute to non-alcoholic fatty liver disease (NAFLD) than a high-fat diet with the same caloric content. The HRCD effect is associated with decreased functions of sirtuin 1 (SIRT1). β-Cryptoxanthin (BCX), a provitamin A carotenoid found primarily in red sweet peppers, has been shown to be protective against NAFLD. BCX can be cleaved by β-carotene-15, 15'-oxygenase (BCO1), and β-carotene-9', 10'-oxygenase (BCO2) to produce bioactive metabolites. BCO1/BCO2 polymorphisms have been observed in human and rodents. In this study, we investigated whether the protective effect of BCX against HRCD-induced NAFLD was dependent on, or independent of BCO1/BCO2, and whether the upregulation of SIRT1 was the underlying mechanism of its physiological actions. At 6 weeks of age, BCO1/BCO2 double knockout (BCO1/BCO2 DKO) mice and wild type (WT) mice from a C57BL/6J genetic background were randomly assigned to either the HRCD (n=15, 66.5 % of energy as carbohydrate including sucrose and maltodextrin) or the HRCD with BCX (n=15, 10 mg BCX/kg diet) group for 24 weeks. The dose of BCX (paprika extract rich in 11% BCX from OmniActive) was equivalent to that on daily human consumption of 3-4 ounces of a sweet red pepper. BCX feeding significantly reduced hepatic steatosis score in both WT and BCO1/BCO2 DKO mice compared to their respective HRCD counterparts (P < 0.05). Moreover, BCX feeding significantly reduced hepatic concentrations of triglyceride and total cholesterol levels in BCO1/BCO2 DKO mice, compared to the corresponding HRCD group. These hepatic changes by BCX feeding were related to the significant upregulation of mRNA and protein levels of nicotinamide phosphoribosyltransferase (NAMPT) and SIRT1, downregulation of mRNA levels of the cholesterol biosynthesis marker (HMG-CoAR) and lipogenesis markers (SREBP-1C, ACC, FAS), and increases in mRNA levels of the fatty acid β-oxidation marker (PPARα). In conclusion, our results provided compelling experimental evidence that BCX has protective effects against HRCD-induced NAFLD potentially by regulating NAMPT/SIRT1 pathway independent of carotenoid cleavage enzymes.
Publications
- Type:
Conference Papers and Presentations
Status:
Submitted
Year Published:
2018
Citation:
Ji Ye Lim, Chun Liu, Kang-Quan Hu, Donald E. Smith, Xiang-Dong Wang. Ablation of carotenoid cleavage enzymes (BCO1 and BCO2) induced NAFLD by altering FXR/miR-34a/SIRT1 pathway in mice. (The manuscript has been submitted and the abstract will be presented in the 2018 ASN meeting.
- Type:
Conference Papers and Presentations
Status:
Submitted
Year Published:
2018
Citation:
Ji Ye Lim, Chun Liu, Kang-Quan Hu, Donald E. Smith, Xiang-Dong Wang. Beta-Cryptoxanthin alleviates high-refined-carbohydrate diet-induced NAFLD by regulating NAMPT/SIRT1 independent of carotenoid cleavage enzymes in mice. Abstract will be presented in the 2018 ASN meeting.
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