Friday, March 21, 2014

Dietary betaine may help prevent NTDs

BACKGROUND: Low maternal intake of dietary choline and betaine (a choline derivative) has recently been investigated as a possible risk factor for neural tube defects (NTDs)
METHODS: This case-control study examined the NTD risk associated with choline and betaine in 409 Mexican-American women who gave birth during 1995 to 2000 in the 14-county border region of Texas RESULTS: Using data from the food frequency questionnaire and the lowest quartiles of intake as the reference categories, a protective association was suggested between higher intakes of choline and betaine and NTD risk although the 95% confidence intervals for all risk estimates included 1.0. For choline intake in the second, third, and fourth quartiles, adjusted odds ratios were 1.2, 0.80, and 0.89, respectively. Betaine appeared more protective with odds ratios of 0.62, 0.73, and 0.61, respectively, for the second, third, and fourth quartiles of intake.
CONCLUSION: Study findings suggest that dietary betaine may help to prevent NTDs.

Lavery, A.M., et al., Dietary intake of choline and neural tube defects in Mexican Americans. Birth Defects Res A Clin Mol Teratol, 2014

Thursday, February 27, 2014

Betaine suppressed amyloid-beta formation, a component of senile plaques related to Alzheimer disease

Betaine was an endogenous catabolite of choline, which could be isolated from vegetables and marine products. Betaine could promote the metabolism of homocysteine in healthy subjects and was used for hyperlipidemia, coronary atherosclerosis, and fatty liver in clinic. Recent findings shown that Betaine rescued neuronal damage due to homocysteine induced Alzheimer's disease (AD) like pathological cascade, including tau hyperphosphorylation and amyloid-beta (Abeta) deposition. Abeta was derived from amyloid precursor protein (APP) processing, and was a triggering factor for AD pathological onset. Here, we demonstrated that Betaine reduced Abeta levels by altering APP processing in N2a cells stably expressing Swedish mutant of APP. Betaine increased alpha-secretase activity, but decreased beta-secretase activity. Our data indicate that Betaine might play a protective role in Abeta production.

Liu, X.P., et al., Betaine suppressed Abeta generation by altering amyloid precursor protein processing. Neurol Sci, 2014

Prognostic value of choline and betaine depends on intestinal microbiota-generated metabolite TMAO

AIMS: Recent metabolomics and animal model studies show trimethylamine-N-oxide (TMAO), an intestinal microbiota-dependent metabolite formed from dietary trimethylamine-containing nutrients such as phosphatidylcholine (PC), choline, and carnitine, is linked to coronary artery disease pathogenesis. Our aim was to examine the prognostic value of systemic choline and betaine levels in stable cardiac patients. METHODS AND RESULTS: We examined the relationship between fasting plasma choline and betaine levels and risk of major adverse cardiac events (MACE = death, myocardial infraction, stroke) in relation to TMAO over 3 years of follow-up in 3903 sequential stable subjects undergoing elective diagnostic coronary angiography. In our study cohort, median (IQR) TMAO, choline, and betaine levels were 3.7 (2.4-6.2)muM, 9.8 (7.9-12.2)muM, and 41.1 (32.5-52.1)muM, respectively. Modest but statistically significant correlations were noted between TMAO and choline (r = 0.33, P < 0.001) and less between TMAO and betaine (r = 0.09, P < 0.001). Higher plasma choline and betaine levels were associated with a 1.9-fold and 1.4-fold increased risk of MACE, respectively (Quartiles 4 vs. 1; P < 0.01, each). Following adjustments for traditional cardiovascular risk factors and high-sensitivity C-reactive protein, elevated choline [1.34 (1.03-1.74), P < 0.05], and betaine levels [1.33 (1.03-1.73), P < 0.05] each predicted increased MACE risk. Neither choline nor betaine predicted MACE risk when TMAO was added to the adjustment model, and choline and betaine predicted future risk for MACE only when TMAO was elevated. CONCLUSION: Elevated plasma levels of choline and betaine are each associated with incident MACE risk independent of traditional risk factors. However, high choline and betaine levels are only associated with higher risk of future MACE with concomitant increase in TMAO.

Wang, Z., et al., Prognostic value of choline and betaine depends on intestinal microbiota-generated metabolite trimethylamine-N-oxide. Eur Heart J, 2014

Betaine supplementation improved high fructose- induced hyperuricemia, insulin resistance, dyslipidemia and systemic inflammation in rats

High fructose intake causes metabolic syndrome, being an increased risk of chronic kidney disease development in humans and animals. In this study, we examined the influence of betaine on high-fructose-induced renal damage involving renal inflammation, insulin resistance and lipid accumulation in rats and explored its possible mechanisms. Betaine was found to improve high-fructose-induced metabolic syndrome including hyperuricemia, dyslipidemia and insulin resistance in rats with systemic inflammation. Betaine also showed a protection against renal dysfunction and tubular injury with its restoration of the increased glucose transporter 9 and renal-specific transporter in renal brush bolder membrane and the decreased organic anion transporter 1 and adenosine-triphosphatebinding cassette transporter 2 in the renal cortex in this model. These protective effects were relevant to the anti-inflammatory action by inhibiting the production of inflammatory cytokines including interleukin (IL)-1â, IL-18, IL-6 and tumor necrosis factor-á in renal tissue of high-fructose-fed rat, being more likely to suppress renal NOD-like receptor superfamily, pyrin domain containing 3 inflammasome activation than nuclear factor êB activation. Subsequently, betaine with anti-inflammation ameliorated insulin signaling impairment by reducing the up-regulation of suppressor of cytokine signaling 3 and lipid accumulation partly by regulating peroxisome proliferator-activated receptor á/palmityltransferase 1/carnitine/organic cation transporter 2 pathway in kidney of high-fructose-fed rats. These results indicate that the inflammatory inhibition plays a pivotal role in betaine’s improvement of high-fructose-induced renal injury with insulin resistance and lipid accumulation in rats.

Fan, C.-Y., et al., Betaine supplementation protects against high-fructose-induced renal injury in rats. The Journal of Nutritional Biochemistry, 2014. 25(3): p. 353-62

Friday, January 31, 2014

Use of betaine in liver injury

Betaine, also known as trimethylglycine, is an important human nutrient obtained from a variety of foods and also can be synthesized from choline. Betaine is much more abundant in kidney and liver compared to other mammalian organs. The principal role of betaine in the kidney is osmoprotection in cells of the medulla and it enters these cells via the betaine/gamma-aminobutyric acid (GABA) transporter protein (BGT1), which is upregulated by hyperosmotic stress. This process has been studied in great detail. In liver, the main role of betaine is a methyl donor in the methionine cycle. However, recent studies showed that BGT1 is much more abundant in liver compared to kidney medulla. Despite this, the role of BGT1 in liver has received little attention. Entry of betaine into liver cells is a necessary first step for its action at the cellular level. Increased interest in betaine has developed because of a number of therapeutic uses. These include treatment of nonalcoholic fatty liver and hyperhomocysteinemia, a risk factor for atherosclerotic disease. Several important questions need to be addressed to better understand the potential of betaine as a therapeutic agent for other liver diseases, such as alcohol-induced injury. Heavy alcohol consumption is the most common cause for liver-related deaths and altered liver metabolism may contribute to hepatic, vascular, coronary, and cerebral diseases.

Kempson, S.A. et al, Betaine transport in kidney and liver: use of betaine in liver injury. Cell Physiol Biochem, 2013. 32(7): p. 32-40

Thursday, January 16, 2014

Inadequate betaine and choline intake may contribute to autism metabolic abnormalities

Abnormalities in folate-dependent one-carbon metabolism have been reported in many children with autism. Because inadequate choline and betaine can negatively affect folate metabolism and in turn downstream methylation and antioxidant capacity, we sought to determine whether dietary intake of choline and betaine in children with autism was adequate to meet nutritional needs based on national recommendations. Three-day food records were analyzed for 288 children with autism (ASDs) who participated in the national Autism Intervention Research Network for Physical Health (AIR-P) Study on Diet and Nutrition in children with autism. Plasma concentrations of choline and betaine were measured in a subgroup of 35 children with ASDs and 32 age-matched control children. The results indicated that 60-93% of children with ASDs were consuming less than the recommended Adequate Intake (AI) for choline. Strong positive correlations were found between dietary intake and plasma concentrations of choline and betaine in autistic children as well as lower plasma concentrations compared to the control group. We conclude that choline and betaine intake is inadequate in a significant subgroup of children with ASDs and is reflected in lower plasma levels. Inadequate intake of choline and betaine may contribute to the metabolic abnormalities observed in many children with autism and warrants attention in nutritional counseling.

Hamlin, J. C., Pauly, M., Melnyk, S., Pavliv, O., Starrett, W., Crook, T. A. and James, S. J., 2013. Dietary intake and plasma levels of choline and betaine in children with autism spectrum disorders. Autism Res Treat: 578429

Thursday, January 9, 2014

The relationship between betaine, homocysteine, and BHMT expression in hibernating and active mammalian brain

Elevated homocysteine is an important risk factor that increases cerebrovascular and neurodegenerative disease morbidity. In mammals, B vitamin supplementation can reduce homocysteine levels. Whether, and how, hibernating mammals, that essentially stop ingesting B vitamins, maintain homocysteine metabolism and avoid cerebrovascular impacts and neurodegeneration remain unclear. Here, we compare homocysteine levels in the brains of torpid bats, active bats and rats to identify the molecules involved in homocysteine homeostasis. We found that homocysteine does not elevate in torpid brains, despite declining vitamin B levels. At low levels of vitamin B6 and B12, we found no change in total expression level of the two main enzymes involved in homocysteine metabolism (methionine synthase and cystathionine beta-synthase), but a 1.85-fold increase in the expression of the coenzyme-independent betaine-homocysteine S-methyltransferase (BHMT). BHMT expression was observed in the amygdala of basal ganglia and the cerebral cortex where BHMT levels were clearly elevated during torpor. This is the first report of BHMT protein expression in the brain and suggests that BHMT modulates homocysteine in the brains of hibernating bats. BHMT may have a neuroprotective role in the brains of hibernating mammals and further research on this system could expand our biomedical understanding of certain cerebrovascular and neurodegenerative disease processes.

Zhang, Y., et al., Homocysteine homeostasis and betaine-homocysteine s-methyltransferase expression in the brain of hibernating bats. PLoS One, 2013. 8(12): p. e85632