m 6A RNA Methylation Decreases Atherosclerotic Vulnerable Plaque Through Inducing T Cells

ABSTRACT Introduction: Knockdown of fat mass and obesity-associated gene (FTO) can induce N6-methyladenosine (m 6A) ribonucleic acid (RNA) methylation. The objective of this study was to explore the effect of m 6A RNA methylation on atherosclerotic vulnerable plaque by FTO knockdown. Methods: A total of 50 New Zealand white rabbits were randomly divided into pure high-fat group, sham operation group, vulnerable plaque group, empty load group, and FTO knockdown group (10 rabbits/group). Results: Flow cytometry showed that helper T (Th) cells in the FTO knockdown group accounted for a significantly higher proportion of lymphocytes than in the vulnerable plaque group and empty load group (P<0.05). Th cells were screened by cell flow. The level of m 6A RNA methylation in the FTO knockdown group was significantly higher than in the vulnerable plaque group and empty load group (P<0.05). The levels of total cholesterol, triglyceride, and low-density lipoprotein C were higher at the 12th week than at the 1st week, but the high-density lipoprotein C level was lower at the 12th week than at the 1st week. At the 12th week, the interleukin-7 level was significantly lower in the adeno-associated virus-9 (AVV9)-FTO short hairpin RNA group than in the control and AVV9-green fluorescent protein groups (P<0.001). Conclusion: After successfully establishing a vascular parkinsonism rabbit model, m 6A RNA methylation can decrease Th cells and vulnerable atherosclerotic plaques.

Risk Assessment of "Other Substances" –L-arginine and Arginine Alpha-ketoglutarate

The Norwegian Scientific Committee for Food Safety (Vitenskapskomiteen for mattrygghet, VKM) has, at the request of the Norwegian Food Safety Authority (Mattilsynet; NFSA), assessed the risk of "other substances" in food supplements and energy drinks sold in Norway. VKM has assessed the risk of doses given by NFSA. The risk assessments are the scientific basis for NFSA in its efforts to regulate the use of "other substances". "Other substances" are described in the food supplement directive 2002/46/EC as substances other than vitamins or minerals that have a nutritional or physiological effect. It is added mainly to food supplements, but also to energy drinks and other foods. VKM has not in this series of risk assessments of "other substances" evaluated any claimed beneficial effects from these substances, only possible adverse effects. The present report is a risk assessment of the amino acid L-arginine and L-arginine alpha-ketoglutarate (AAKG), a salt of arginine. It is based on published articles retrieved from a literature search and previous risk assessments of L-arginine. According to information from NFSA, L-arginine is an ingredient in food supplements sold in Norway. NSFA has requested a risk assessment of L-arginine, which according to the information provided by NFSA is found in food supplements in the doses 3000, 3500, 4000, 4500, 5000, 5500, 6000 and 6800 mg/day. Arginine alpha-ketoglutarate is found in food supplements in doses of 1000 and 2000 mg/day. Arginine is a constituent of all food proteins. Dairy products, beef, pork, poultry, wild game and seafood, as well as plant sources such as wheat germ and flour, oatmeal and nuts are good sources of arginine. Arginine is a conditionally essential amino acid, meaning that under most circumstances endogenous synthesis by the human body is sufficient. However, the biosynthetic pathway may under certain conditions produce insufficient amounts. In such cases a dietary supply is needed. Individuals with poor nutrition or certain physical conditions are examples of vulnerable groups. Under normal conditions, endogenous production of arginine is 15-20 g/day. The requirements for L-arginine in adults are 117 mg/kg body weight (bw) per day (WHO, 2007), i.e. for a 70 kg adult person, the requirement is 8.2 g per day. The mean daily dietary intake for all life stage and gender groups of arginine is approximately 4.2 g/day (1988–1994 NHANES III, USA). Arginine is physiologically active in the L-form, which is synthesised by endothelial cells and excreted with urine. The major part of body L-arginine is found in proteins. However, L-arginine is also substrate of nitric-oxide, a potent vasodilator, which may play a major role in regulating blood pressure and improve vascular function. Arginine, supplied as alpha-ketoglutarate, has been observed to increase nitric-oxide production and is mostly studied in athletes because of its claimed enhancing effect on physical performance. Due to the lack of adequate scientific information, a no observed adverse effect level (NOAEL) or lowest observed adverse effect level (LOAEL) of arginine has not been identified, thus a tolerable upper intake level for arginine has not been established. Most studies of arginine supplements have been of relatively short duration. The two most relevant randomised placebo-controlled trials for the current risk assessment are those published by Monti et al. (2012) and Lucotti et al. (2009). Both provided a daily dose of 6.4 g arginine, for a duration of 6 and 18 months, respectively. In both studies, adverse events did not differ between arginine and placebo groups. Thus, based on the studies reviewed as well as previous reports, VKM will use the value 6.4 g/day as value for comparison in the risk characterisation of L-arginine. The dose 6.4 g/day of arginine corresponds to 91 mg/kg bw per day in a 70 kg person. AAKG is one of several compounds that have been used as a source of arginine in food supplements. It has been studied in healthy athletic men without serious adverse side effects. However, studies of AAKG supplementation are too scarce to draw conclusions for this specific arginine compound. No data are available indicating whether children or adolescents have different tolerance levels than adults for L-arginine. No tolerance level is set for L-arginine specifically for children or adolescents. The conclusions are therefore based on the assumption of similar tolerance for children and adolescents, per kg body weight, as for adults. VKM concludes that: In adults (≥18 years), the specified doses of 3000, 3500, 4000, 4500, 5000, 5500 and 6000 mg/day of L-arginine in food supplement are considered unlikely to cause adverse health effects. The dose 6800 mg/day may represent a risk of adverse health effects. In adolescents (14 to <18 years), the specified doses 3000, 3500, 4000, 4500, 5000, 5500 mg/day L-arginine in food are considered unlikely to cause adverse health effects, whereas the doses 6000 and 6800 mg/day may represent a risk of adverse health effects. In children (10 to <14 years), the specified doses 3000 and 3500 mg/day L-arginine in food supplements are considered unlikely to cause adverse health effects, whereas the doses 4000, 4500, 5000, 5500, 6000 and 6800 mg/day may represent a risk of adverse health effects. Children below 10 years were not included in the terms of reference. No dosage of arginine alpha-ketoglutarate in food supplements can be evaluated, due to lack of data. In terms of the arginine content of AAKG, a dose of 1000 mg AAKG contains 544 mg arginine and 450 mg alpha-ketoglutarate (based on the molecular weight of 174.2 g/mol for arginine and 144.1 g/mol for alpha-ketoglutarate). A dose of 2000 mg AAKG, the highest dose found in food supplements sold in Norway, contains 1088 mg arginine and 900 mg alpha-ketoglutarate. This amount of arginine is well below the lowest specified dose of 3000 mg/day L-arginine found in food supplements.

Asociación entre el polimorfismo rs9939609 del gen FTO con la ingesta energética, macronutrientes y consumo de alcohol en población chilena / Association of the FTO (rs9939609) genotype with energy intake

Background: Fat-mass-associated-gene (FTO) is associated with higher energy intake and specific food preferences. Aim: To investigate the association of the FTO genotype with energy intake, macronutrient and alcohol consumption. Material and Methods: Four hundred and nine participants of the GENADIO (Genes, Environment, Diabetes and Obesity) study were included. Energy intake, macronutrient and alcohol consumption were the outcomes of interest. The association of FTO (rs9939609) genotype with these outcomes was investigated using linear regression analyses, adjusting for confounding variables. Results: After adjusting for socio-demographic factors, being a carrier of the risk allele for the FTO gene was associated with a higher energy intake (173 kcal per each extra copy of the risk variant [95% confidence intervals (CI): 45; 301], (P = 0.008). After adjusting for lifestyle factors and body mass index, the association was slightly attenuated but remained significant (144 kcal [95% CI: 14; 274], p = 0.030). Conclusions: The FTO genotype is associated with a higher energy intake.

Asociación entre el polimorfismo rs9939609 del gen FTO y marcadores de adiposidad en población adulta chilena / Association between FTO (ns9939609) genotype and adiposity markers in Chilean adults

Background: Numerous studies have identified the role of Fat-mass-associated-gene (FTO) in the development of obesity. Aim: To investigate the association of FTO gene with adiposity markers in Chilean adults. Material and Methods: 409 participants were included in this cross-sectional study. The association between FTO (rs9939609) genotype and adiposity markers was determined using linear regression analyses. Adiposity markers included were: body weight, body mass index, fat mass, waist circumference, hip circumference and waist/hip ratio. Results: A fully adjusted model showed a significant association between FTO genotype and body weight (2.16 kg per each extra copy of the risk allele [95% confidence intervals (CI): 0.45 to 3.87], p = 0.014), body mass index (0.61 kg.m-2 [95% CI: 0.12 to 1.20], p = 0.050) and fat mass (1.14% [95% CI: 0.39 to 1.89], p = 0.010). The greater magnitude of association was found between the FTO gene and fat mass when the outcomes were standardized to z-score. Conclusions: This study confirms an association between the FTO gene and adiposity markers in Chilean adults, which is independent of major confounding factors.

Alpha-Ketoglutarate: Physiological Functions and Applications

Alpha-ketoglutarate (AKG) is a key molecule in the Krebs cycle determining the overall rate of the citric acid cycle of the organism. It is a nitrogen scavenger and a source of glutamate and glutamine that stimulates protein synthesis and inhibits protein degradation in muscles. AKG as a precursor of glutamate and glutamine is a central metabolic fuel for cells of the gastrointestinal tract as well. AKG can decrease protein catabolism and increase protein synthesis to enhance bone tissue formation in the skeletal muscles and can be used in clinical applications. In addition to these health benefits, a recent study has shown that AKG can extend the lifespan of adult Caenorhabditis elegans by inhibiting ATP synthase and TOR. AKG not only extends lifespan, but also delays age-related disease. In this review, we will summarize the advances in AKG research field, in the content of its physiological functions and applications.

Identification of a New Selective Chemical Inhibitor of Mutant Isocitrate Dehydrogenase-1

BACKGROUND: Recent genome-wide sequencing studies have identified unexpected genetic alterations in cancer. In particular, missense mutations in isocitrate dehydrogenase-1 (IDH1) at arginine 132, mostly substituted into histidine (IDH1-R132H) were observed to frequently occur in glioma patients. METHODS: We have purified recombinant IDH1 and IDH1-R132H proteins and monitored their catalytic activities. In parallel experiments, we have attempted to find new selective IDH1-R132H chemical inhibitor(s) from a fragment-based chemical library. RESULTS: We have found that IDH1, but not IDH1-R132H, can catalyze the conversion of isocitrate into alpha-ketoglutarate (alpha-KG). In addition, we have observed that IDH1-R132H was more efficient than IDH1 in converting alpha-KG into (R)-2-hydroxyglutarate (R-2HG). Moreover, we have identified a new hit molecule, e.g., 2-(3-trifluoromethylphenyl)isothioazol-3(2H)-one as a new selective IDH1-R132H inhibitor. CONCLUSIONS: We have observed an underlying biochemical mechanism explaining how a heterozygous IDH1 mutation contributes to the generation of R-2HG and increases cellular histone H3 trimethylation levels. We have also identified a novel selective IDH1-R132H chemical hit molecule, e.g., 2-(3-trifluoromethylphenyl)isothioazol-3(2H)-one, which could be used for a future lead development against IDH1-R132H.

Protective role of alpha-ketoglutarate against massive doses of cyanide in rats.

Cyanide is a highly toxic cellular poison that requires immediate and aggressive treatments. Combination of sodium nitrite (SN) and sodium thiosulfate (STS) is the treatment of choice but oral treatment of alpha-ketoglutarate (A-KG) has also been shown to significantly antagonize cyanide poisoning in laboratory animals. This study reports the efficacy of various treatment regimens as : (i) repeated doses of A-KG after simultaneous treatment of A-KG and STS, (ii) repeated doses of A-KG after pre-treatment of SN, STS and A-KG, (iii) repeated doses of STS after pre-treatment of SN, STS and A-KG, and (iv) repeated doses of A-KG and STS after pretreatment of SN, STS and A-KG on mortality of female rats exposed to massive doses of potassium cyanide. A maximum of 40-folds protection was observed when A-KG at 1.0 g kg-1 after 2 hr and 0.5 g kg-1 after 4 hr was repeated following the pre-treatment of SN (0.025 g kg-1; subcutaneous; -45 min), STS (1.0 g kg-1; intraperitoneal; -15 min) and A-KG (2.0 g kg-1; oral; -10 min). Similar protection was also conferred by repeating 0.5 g kg-1 each of A-KG and STS 2 hr after pre-treatment of SN, STS and A-KG. Also, 38-folds protection after simultaneous administration of 2.0 g kg-1 A-KG and 1.0 g kg-1 STS, followed by 2.0 g kg-1 A-KG after 2 hr was noteworthy. The results indicate that repeated treatment of A-KG alone after simultaneous treatment of A-KG and STS or repeated treatment of A-KG alone or with STS after pre-treatment of A-KG, SN and STS have immense potential in challenging extremely high doses of cyanide as compared to the antidotes given once. The study has implications in the development of A-KG as an alternate treatment for cyanide poisoning.