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Glucose restriction can extend normal cell lifespan and impair precancerous cell growth through epigenetic control of hTERT and p16 expression. Li Y, Liu L, Tollefsbol TO. FASEB J. 2009 Dec 17. [Epub ahead of print] PMID: 20019239 doi: 10.1096/fj.09-149328 Cancer cells metabolize glucose at elevated rates and have a higher sensitivity to glucose reduction. However, the precise molecular mechanisms leading to different responses to glucose restriction between normal and cancer cells are not fully understood. We analyzed normal WI-38 and immortalized WI-38/S fetal lung fibroblasts and found that glucose restriction resulted in growth inhibition and apoptosis in WI-38/S cells, whereas it induced lifespan extension in WI-38 cells. Moreover, in WI-38/S cells glucose restriction decreased expression of hTERT (human telomerase reverse transcriptase) and increased expression of p16(INK4a). Opposite effects were found in the gene expression of hTERT and p16 in WI-38 cells in response to glucose restriction. The altered gene expression was partly due to glucose restriction-induced DNA methylation changes and chromatin remodeling of the hTERT and p16 promoters in normal and immortalized WI-38 cells. Furthermore, glucose restriction resulted in altered hTERT and p16 expression in response to epigenetic regulators in WI-38 rather than WI-38/S cells, suggesting that energy stress-induced differential epigenetic regulation may lead to different cellular fates in normal and precancerous cells. Collectively, these results provide new insights into the epigenetic mechanisms of a nutrient control strategy that may contribute to cancer therapy as well as antiaging approaches.

n-3 fatty acids and gene expression. Deckelbaum RJ, Worgall TS, Seo T. Am J Clin Nutr. 2006 Jun;83(6 Suppl):1520S-1525S. Review. Erratum in: Am J Clin Nutr. 2006 Oct;84(4):949. PMID: 16841862 Accumulating evidence in both humans and animal models clearly indicates that a group of very-long-chain polyunsaturated fatty acids, the n-3 fatty acids (or omega-3), have distinct and important bioactive properties compared with other groups of fatty acids. n-3 Fatty acids are known to reduce many risk factors associated with several diseases, such as cardiovascular diseases, diabetes, and cancer. The mechanisms whereby n-3 fatty acids affect gene expression are complex and involve multiple processes. As examples, n-3 fatty acids regulate 2 groups of transcription factors, such as sterol-regulatory-element binding proteins and peroxisome proliferator-activated receptors, that are critical for modulating the expression of genes controlling both systemic and tissue-specific lipid homeostasis. Modulation of specific genes by n-3 fatty acids and cross-talk between these genes are responsible for many effects of n-3 fatty acids.

The effect of select nutrients on serum high-density lipoprotein cholesterol and apolipoprotein A-I levels. Mooradian AD, Haas MJ, Wong NC. Endocr Rev. 2006 Feb;27(1):2-16. Epub 2005 Oct 21. Review. PMID: 16243964 One of the factors contributing to the increased risk of developing premature atherosclerosis is low plasma concentrations of high-density lipoprotein (HDL) cholesterol (HDLc). Multiple potential mechanisms account for the cardioprotective effects of HDL and its main protein apolipoprotein A-I (apo A-I). The low plasma concentrations of HDL could be the result of increased fractional clearance and reduced expression of apo A-I. To this end, nutrients play an important role in modulating the fractional clearance rate, as well as the rate of apo A-I gene expression. Because medical nutrition therapy constitutes the cornerstone of management of dyslipidemias, it is essential to understand the mechanisms underlying the changes in HDL level in response to alterations in dietary intake. In this review, we will discuss the effect of select nutrients on serum HDLc and apo A-I levels. Specifically, we will review the literature on the effect of carbohydrates, fatty acids, and ketones, as well as some of the nutrient-related metabolites, such as glucosamine and the prostanoids, on apo A-I gene expression. Because there are multiple mechanisms involved in the regulation of serum HDLc levels, changes in gene transcription do not necessarily correlate with clinical observations on serum levels of HDLc.

The present study, thus, raises the possibility that DHA may exert pro-apoptotic and antitumoral effects through proteasomal regulation of beta-catenin levels and alterations in the expression of TCF-beta-catenin target genes. Docosahexaenoic acid induces proteasome-dependent degradation of beta-catenin, down-regulation of survivin and apoptosis in human colorectal cancer cells not expressing COX-2. Calviello G, Resci F, Serini S, Piccioni E, Toesca A, Boninsegna A, Monego G, Ranelletti FO, Palozza P. Carcinogenesis. 2007 Jun;28(6):1202-9. Epub 2006 Dec 20. PMID: 17183061 doi:10.1093/carcin/bgl254

These data indicate that fish oil feeding downregulated the endogenous PPAR-activation system and increased antioxidant gene expressions to protect against ROS excess Fish oil feeding alters liver gene expressions to defend against PPARalpha activation and ROS production. Takahashi M, Tsuboyama-Kasaoka N, Nakatani T, Ishii M, Tsutsumi S, Aburatani H, Ezaki O. Am J Physiol Gastrointest Liver Physiol. 2002 Feb;282(2):G338-48. PMID: 11804856

Floyd Chilton and colleagues wanted to examine whether theses fatty acids might have other effects, and developed a dietary intervention strategy in which 27 healthy humans were fed a controlled diet mimicking the w6/w3 ratios of early humans over 5 weeks. They then looked at the gene levels of immune signals and cytokines (protein immune messengers), that impact autoimmunity and allergy in blood cells and found that many key signaling genes that promote inflammation were markedly reduced compared to a normal diet, including a signaling gene for a protein called PI3K, a critical early step in autoimmune and allergic inflammation responses. This study demonstrates, for the first time in humans, that large changes in gene expression are likely an important mechanism by which these omega fatty acids exert their potent clinical effects

DHA and EPA generally modulated different sets of genes, although a few common effects were noted. In our approach, we used preneoplastic adenoma cells which are a relevant model for target cells of chemoprevention. If verified with real time PCR, these results identify genes and targets for chemoprevention of colon cancer. Modulation of gene expression in eicosapentaenoic acid and docosahexaenoic acid treated human colon adenoma cells. Habermann N, Lund EK, Pool-Zobel BL, Glei M. Genes Nutr. 2009 Mar;4(1):73-6. Epub 2009 Feb 21. PMID: 19234733 doi: 10.1007/s12263-009-0112-y.

Rosmarinic acid antagonizes activator protein-1-dependent activation of cyclooxygenase-2 expression in human cancer and nonmalignant cell lines. Scheckel KA, Degner SC, Romagnolo DF. J Nutr. 2008 Nov;138(11):2098-105. PMID: 18936204

"As far as I can tell, MK-4 is capable of performing all the functions of vitamin K. MK-4 can even activate blood clotting factors, which is a role traditionally ascribed to vitamin K1. Babies are often born clotting deficient, which is why we give newborns vitamin K1 injections in the U.S. to prevent hemorrhaging. In Japan, they give children MK-4 to prevent hemorrhage, an intervention that is very effective. Could that have to do with the fact that Japan has half the infant mortality rate of the U.S.? Today, I found another difference between MK-4 and MK-7. I was reading a paper about SXR-independent effects of vitamin K2 on gene expression. The investigators found that MK-4 strongly activates transcription of two specific genes in osteoblast cells. Osteoblasts are cells that create bone tissue. The genes are GDF15 and STC2 and they're involved in bone and cartilage formation. They tested K1 and MK-7, and in contrast to MK-4, they did not activate transcription of the genes in the slightest. This shows that MK-4 has effects on gene expression in bone tissue that MK-7 doesn't have. That being said, MK-7 may still have a place in a healthy diet. Just because it can't do everything MK-4 can, doesn't mean it has no role. It may be able to fill in for MK-4 in some functions, or reduce the dietary need for MK-4. But no one really knows at this point. Hunter-gatherers would have had a source of longer menaquinones, including MK-7, from livers. So it's possible that we're adapted to a modest MK-7 intake on top of MK-4. "

Berberine is a novel cholesterol-lowering drug working through a unique mechanism distinct from statins. Kong W, Wei J, Abidi P, Lin M, Inaba S, Li C, Wang Y, Wang Z, Si S, Pan H, Wang S, Wu J, Wang Y, Li Z, Liu J, Jiang JD. Nat Med. 2004 Dec;10(12):1344-51. Epub 2004 Nov 7. PMID: 15531889 doi:10.1038/nm1135 We identify berberine (BBR), a compound isolated from a Chinese herb, as a new cholesterol-lowering drug. Oral administration of BBR in 32 hypercholesterolemic patients for 3 months reduced serum cholesterol by 29%, triglycerides by 35% and LDL-cholesterol by 25%. Treatment of hyperlipidemic hamsters with BBR reduced serum cholesterol by 40% and LDL-cholesterol by 42%, with a 3.5-fold increase in hepatic LDLR mRNA and a 2.6-fold increase in hepatic LDLR protein. Using human hepatoma cells, we show that BBR upregulates LDLR expression independent of sterol regulatory element binding proteins, but dependent on ERK activation. BBR elevates LDLR expression through a post-transcriptional mechanism that stabilizes the mRNA. Using a heterologous system with luciferase as a reporter, we further identify the 5' proximal section of the LDLR mRNA 3' untranslated region responsible for the regulatory effect of BBR. These findings show BBR as a new hypolipidemic drug with a mechanism of action different from that of statin drugs.

Berberine lowers blood glucose in type 2 diabetes mellitus patients through increasing insulin receptor expression. Zhang H, Wei J, Xue R, Wu JD, Zhao W, Wang ZZ, Wang SK, Zhou ZX, Song DQ, Wang YM, Pan HN, Kong WJ, Jiang JD. Metabolism. 2009 Sep 3 doi:10.1016/j.metabol.2009.07.029 Liver function was improved greatly in these patients by showing reduction of liver enzymes. Our results confirmed the activity of BBR on InsR in humans and its relationship with the glucose-lowering effect. Together with our previous report, we strongly suggest BBR as an ideal medicine for T2DM with a mechanism different from metformin and rosiglitazone.

Berberine inhibits adipogenesis in high-fat diet-induced obesity mice. Hu Y, Davies GE. Fitoterapia. 2009 Oct 25. [Epub ahead of print] PMID: 19861153 doi:10.1016/j.fitote.2009.10.010 Our previous studies illustrated that berberine inhibited adipogenesis in murine-derived 3T3-L1 preadipocytes and human white preadipocytes. In this study, the effects of berberine on the adipogenesis of high-fat diet-induced obesity (FD) or normal diet (ND) mice and possible transcriptional impact are investigated. The results demonstrated that in FD mice, berberine reduced mouse weight gain and food intake and serum glucose, triglyceride, and total cholesterol levels accompanied with a down-regulation of PPARgamma expression and an up-regulation of GATA-3 expression. Berberine had no adverse effects on ND mice. These encouraging findings suggest that berberine has excellent pharmacological potential to prevent obesity.

"June 21, 2006 | Michael O'Riordan Rome, Italy - One of the possible ways in which long-chain omega-3 fatty acids play a role in decreasing cardiovascular events is by entering advanced atherosclerotic plaques. According to the results of a new study, investigators were able to show that the incorporation of eicosapentaenoic acid (EPA) into advanced plaque was associated with a decreased expression of various matrix metalloproteinases (MMPs) involved in causing plaque instability, as well as with decreased plaque inflammation. These are results of the Omacor Carotid Endarterectomy Intervention (OCEAN) study, presented here this week at the International Symposium on Atherosclerosis by Dr Philip Calder (University of Southampton, UK). "By increasing the availability of omega-3 fatty acids, they appear in advanced atherosclerotic plaques, indicated in this study by the carotid artery, and this results in lower numbers of macrophages, foam cells, and T cells, as well as the lower expression of inflammatory markers," said Calder. "Histologically, this results in a plaque that appears to be less inflamed and more stable. This may contribute to reduced mortality in patients consuming omega-3 fatty acids, for example, in the GISSI Prevenzione trial.""

Conjugated linoleic acid promotes human adipocyte insulin resistance through NFkappaB-dependent cytokine production. Chung S, Brown JM, Provo JN, Hopkins R, McIntosh MK. J Biol Chem. 2005 Nov 18;280(46):38445-56. Epub 2005 Sep 9. PMID: 16155293 doi: 10.1074/jbc.M508159200 Collectively, these data demonstrate for the first time that trans-10, cis-12 CLA promotes NFkappaB activation and subsequent induction of IL-6, which are at least in part responsible for trans-10, cis-12 CLA-mediated suppression of peroxisome proliferator-activated receptor gamma target gene expression and insulin sensitivity in mature human adipocytes. In summary, our in vitro data demonstrate that a physiological level of trans-10, cis-12 CLA activates NFκB- and ERK1/2-dependent cytokine production, which together suppress PPARγ and Glut4 levels and lead to impaired glucose uptake. Studies are currently under way examining 1) how CLA regulates PPARγ and the expression of its target genes, 2) the specific signaling role of SV cells and adipocytes in mediating the TG-lowering actions of CLA, and 3) the CLA-induced, upstream signal that activates NFκB and ERK1/2.

Expression of the multiple sclerosis-associated MHC class II Allele HLA-DRB1*1501 is regulated by vitamin D.\nRamagopalan SV, Maugeri NJ, Handunnetthi L, Lincoln MR, Orton SM, Dyment DA, Deluca GC, Herrera BM, Chao MJ, Sadovnick AD, Ebers GC, Knight JC.\nPLoS Genet. 2009 Feb;5(2):e1000369. Epub 2009 Feb 6.\nPMID: 19197344 [

Inhibitions of vascular endothelial growth factor expression and foam cell formation by EGb 761, a special extract of Ginkgo biloba, in oxidatively modified low-density lipoprotein-induced human THP-1 monocytes cells. Liu HJ, Wang XL, Zhang L, Qiu Y, Li TJ, Li R, Wu MC, Wei LX, Rui YC. Phytomedicine. 2009 Jan 7. [Epub ahead of print] PMID: 19135347

Mice fed fish oil and curcumin showed a significantly reduced tumor volume, 25% (P < 0.04) and 43% (P < 0.005), respectively, and importantly, a combination of curcumin and fish oil diet showed > 72% (P < 0.0001) tumor volume reduction. Expression and activity of iNOS, COX-2, and 5-LOX are downregulated, and p21 is upregulated in tumor xenograft fed curcumin combined with fish oil diet when compared to individual diets. The preceding results evidence for the first time that curcumin combined with omega-3 fatty acids provide synergistic pancreatic tumor inhibitory properties. Prevention and treatment of pancreatic cancer by curcumin in combination with omega-3 fatty acids. Swamy MV, Citineni B, Patlolla JM, Mohammed A, Zhang Y, Rao CV. Nutr Cancer. 2008;60 Suppl 1:81-9. PMID: 19003584

Impact of fish oil enriched total parenteral nutrition on DNA synthesis, cytokine release and receptor expression by lymphocytes in the postoperative period. Schauder P, Röhn U, Schäfer G, Korff G, Schenk HD. Br J Nutr. 2002 Jan;87 Suppl 1:S103-10. PMID: 11895146 doi:10.1079/BJN2001463

"Vitamin D is not just a sun-derived vitamin, but is a crucial steroid precursor that is transformed into one of the most potent hormones in the human body for strength, power, lung function and regulating gene expression in every organ system. Athletes need Vitamin D. Dr. Cannell has written quite extensively about the role of vitamin D in athletes"

Bioactive vitamin D or calcitriol is a steroid hormone that has long been known for its important role in regulating body levels of calcium and phosphorus, and in mineralization of bone. More recently, it has become clear that receptors for vitamin D are present in a wide variety of cells, and that this hormone has biologic effects which extend far beyond control of mineral metabolism. The active form of vitamin D binds to intracellular receptors that then function as transcription factors to modulate gene expression. Like the receptors for other steroid hormones and thyroid hormones, the vitamin D receptor has hormone-binding and DNA-binding domains. The vitamin D receptor forms a complex with another intracellular receptor, the retinoid-X receptor, and that heterodimer is what binds to DNA. In most cases studied, the effect is to activate transcription, but situations are also known in which vitamin D suppresses transcription. Each of the forms of vitamin D is hydrophobic, and is transported in blood bound to carrier proteins. The major carrier is called, appropriately, vitamin D-binding protein. The halflife of 25-hydroxycholecalciferol is several weeks, while that of 1,25-dihydroxycholecalciferol is only a few hours. The vitamin D receptor binds several forms of cholecalciferol. Its affinity for 1,25-dihydroxycholecalciferol is roughly 1000 times that for 25-hydroxycholecalciferol, which explains their relative biological potencies