Hepatic Folate Research Articles

A Case Report of Low-Dose Steroid Induced Psychosis in an Older Adult with Rheumatoid Arthritis

IntroductionRheumatoid arthritis (RA) is typically known for its intra-articular manifestations in the joints, and steroids are considered one of the first-line medications for it. Steroids are known for neuropsychiatric manifestations, but it is rarely reported in low-dose steroids.Objectives We describe a case of psychosis in an older adult with RA precipitated by low-dose prednisone with no past history of neuropsychiatric symptoms from steroids in the past five years.MethodsMiss X is a 63-year-old female with past history of RA, major depressive disorder, hypothyroidism, chronic obstructive pulmonary disease, and hypertension, presented with one-week history of irritable mood, increased psychomotor agitation, decreased need for sleep and appetite, and delusions of grandeur and persecution. Her depression had been treated with oral duloxetine 60mg twice daily, oral buspirone 10mg at night, and oral trazodone 150mg at night. She did have a urinary tract infection a week prior, but the psychotic symptoms persisted with antibiotic treatment. Miss X had also been on a monthly taper regimen of low-dose oral prednisone for RA (from 15mg to 5mg) for the past three months and had completed the regimen one week ago. On mental status examination, she was alert and oriented to time, place, and person. Her mood was irritable with lability. She demonstrated tangential speech along with persecutory and grandiose delusions. Attention and concentration was normal with intact immediate and remote memory and impaired recent memory. Abstract ability, judgment, and insight were impaired. Physical examination and vital signs were within normal limits. Laboratory investigations of complete blood count, urine analysis, urine drug screen, thyroid function panel, renal function panel, hepatic function panel, serum sodium, potassium, calcium, thiamine, vitamin B12, folate, and vitamin D did not show any significant abnormalities.ResultsMiss X was admitted to the inpatient psychiatric unit with the diagnosis of medication-induced psychotic disorder, with onset after medication use as per The Diagnostic and Statistical Manual of Mental Disorders 5th edition- Text Revision. Oral olanzapine 10mg at night and oral lithium 300mg twice daily was started along with her home medications of oral duloxetine 60 mg twice daily and oral trazodone 150mg at night. During hospital stay, oral olanzapine was gradually increased to 15mg in the night but had to be reduced back to 10mg in the night due to sedation. Miss X’s symptoms improved during hospital stay and she was discharged on the 13th day of hospitalization with the same psychotropic medication regimen.ConclusionsOur case demonstrates the need for caution in prescribing steroids in older adults as it can precipitate neuropsychiatric symptoms even with a change in use or after withdrawal of steroids.Disclosure of InterestNone Declared

One-carbon metabolite supplementation to heifers for the first 14 d of the estrous cycle alters the plasma and hepatic one-carbon metabolite pool and methionine-folate cycle enzyme transcript abundance in a dose-dependent manner.

The objective of this study was to determine the dose of folate and vitamin B12 in beef heifers fed rumen protected methionine and choline required to maintain increased B12 levels and intermediates of the methionine-folate cycle in circulation. Angus heifers (n = 30; BW = 392.6 ± 12.6 kg) were individually fed and assigned to one of five treatments: 0XNEG: Total mixed ration (TMR) and saline injections at day 0 and 7 of the estrous cycle, 0XPOS: TMR, rumen protected methionine (MET) fed at 0.08% of the diet DM, rumen protected choline (CHOL) fed at 60 g/d, and saline injections at day 0 and 7, 0.5X: TMR, MET, CHOL, 5 mg B12, and 80 mg folate at day 0 and 7, 1X: TMR, MET CHOL, 10 mg vitamin B12, and 160 mg folate at day 0 and 7, and 2X: TMR, MET, CHOL, 20 mg B12, and 320 mg folate at day 0 and 7. All heifers were estrus synchronized but not bred, and blood was collected on day 0, 2, 5, 7, 9, 12, and 14 of a synchronized estrous cycle. Heifers were slaughtered on day 14 of the estrous cycle for liver collection. Serum B12 concentrations were greater in the 0.5X, 1X, and 2X, compared with 0XNEG and 0XPOS on all days after treatment initiation (P < 0.0001). Serum folate concentrations were greater for the 2X treatment at day 5, 7, and 9 of the cycle compared with all other treatments (P ≤ 0.05). There were no differences (P ≥ 0.19) in hepatic methionine-cycle or choline analyte concentrations by treatment. Concentrations of hepatic folate cycle intermediates were always greater (P ≤ 0.04) in the 2X treatment compared with the 0XNEG and 0XPOS heifers. Serum methionine was greater (P = 0.04) in the 0.5X and 2X heifers compared with 0XNEG, and S-adenosylhomocysteine (SAH) tended (P = 0.06) to be greater in the 0.5X heifers and the S-adenosylmethionine (SAM):SAH ratio was decreased (P = 0.05) in the 0.5X treatment compared with the 0XNEG, 0XPOS, and 2X heifers. The hepatic transcript abundance of MAT2A and MAT2B were decreased (P ≤ 0.02) in the 0.5X heifers compared with the 0XNEG, 0XPOS, and 2X heifers. These data support that beef heifers fed rumen protected methionine and choline require 20 mg B12 and 320 mg folate once weekly to maintain increased concentrations of B12 and folate in serum. Furthermore, these data demonstrate that not all supplementation levels are equal in providing positive responses, and that some levels, such as the 0.5X, may result in a stoichiometric imbalance in the one-carbon metabolism pathway that results in a decreased SAM:SAH ratio.

Effect of Methotrexate on Liver in Patient with Rheumatoid Arthritis

Background: Methotrexate helps your immune system from assaulting your body's cells by calming it down. This helps to lessen the inflammation that causes rheumatoid arthritis's swollen and stiff joints, psoriasis' thickened skin, and Crohn's disease's gut damage. Because of its powerful effectiveness and safety, In the treatment of rheumatoid arthritis, methotrexate (MTX) is used as an anchor disease-modifying anti-rheumatic drug (DMARD) (RA).Although MTX aids a huge percentage of RA patients, it is not without adverse effects. When treating rheumatoid arthritis patients with the MTX, wide a variety of adverse effects, from minor to severe, can occur, leading to therapy termination. One putative harmful effect of methotrexate on the due to a local folate deficiency, there is a reduction in hepatic folate stores and toxicity. When MTX used with other medications, further research is needed to improve efficacy while reducing adverse effects. The management of MTX therapy is also reviewed, as well as options for dealing with adverse effects that may arise. Objective: The purpose of this study was to see how methotrexate affected individuals after 6 to 12 months of treatment for rheumatoid arthritis. Methods: Data was collected at the Shalamar hospital, Pakistan, between January 2021 and June 2022. Non-Probability Purposive Sample is the sampling strategy used in this investigation. Following the assignment of a study subject, the research took around 6 months to complete. After giving their informed consent, 120 patients between the ages of 30 and 50 were involved in this study. Data will be acquired using data collection technologies when an informed written permission form has been completed. Result: In this study 120 Rheumatoid Arthritis patients were studied, with 64 males (53.3%) and 56 women (46.7%) having an average age of 40 to 45 years and a range of 30 to 50 years. took part in the study, as shown in the graph (Table 3). In this study, 4 patients are 30 to 35 years old and have a percentage of (3.3%), 18 patients are 36 to 40 years old and have a percentage of (15%), another age group is 41 to 45 years old and has a percentage of (47.5%), and the last age group is 46 to 50 years old and has a percentage of (34.2%), as shown in the table (Table 2). The (Table 5) indicates the usual range of LFTs before Methotrexate, which is completely normal with no fluctuation in LFT parameters. As demonstrated in (Tables 6 and 8) where we examine the before and after effects of Methotrexate on the basis of patient immunity in 79 patients, the values of LFTs alter and become higher in comparison to normal, with a percentage of (65.8%). We compare the impact of Methotrexate on the basis of Gender using cross tabulation, which shows that LFTs were high in 41 males (67.1%) and 38 females (64.9%), as indicated in (Table 10). Finally, we compare the effect of Methotrexate on the basis of age factor as shown in (Table 11). After MTX therapy, RA patients experienced gastrointestinal side effects such as nausea, vomiting, and diarrhea, implying that MTX therapy will definitely affect the LFTs level and, most likely, according to the current study, will raise the LFTs level in blood, which will be treated promptly before further serious complications arise. A timely follow-up will be advised to all patients with consistently high LFTs levels. Conclusion: In this study, we discussed rheumatoid arthritis and the effects of methotrexate on rheumatoid arthritis patients' lives. It would appear that methotrexate is gaining popularity in the treatment of rheumatoid arthritis. Although there is risk of infection &amp; probable cancer, the hazards are much outweighed by the potential therapeutic benefits. We also talked about R.A. diagnostic procedures. We covered the many characteristics of this autoimmune condition as well as several diagnostic approaches in this study.

Dietary modulations of folic acid affect the development of diethylnitrosamine induced hepatocellular carcinoma in a rat model.

The present study evaluated the role of dietary folate modulations in the development of hepatocellular carcinoma (HCC) in a rat model. Male Wistar rats were given diethylnitrosamine (DEN) carcinogen for a period of 18weeks in addition to different folate modulations. Biochemical parameters were assayed and liver tissues were examined using various histopathological stains viz. Hematoxylin and eosin (H&E), Masson's trichrome, Immunohistochemistry (IHC) staining for arginase-1 and α-smooth muscle actin (SMA). Serum folate and hepatic folate stores were decreased and increased in folate deficiency (FD) and folate oversupplemented (FO) group respectively. Analysis of serum liver function tests revealed deranged liver functioning in all the groups. H&E staining of rat liver demonstrated vague nodularity from 2nd to 8th week, fibrosis from 10th to 15th week, cirrhosis and HCC from 16th to 18th week. Combining the observations of H&E with IHC for arginase-1, 14 (50%), 11 (39.3%) and 17 (58.6%) rats showed HCC positivity in FN (folate normal), FD and FO diets respectively. IHC for α-SMA depicted increased staining with progression of the disease from fibrosis to cirrhosis in all the dietary groups. Collectively, findings of all the histopathological stains, revealed increase in the number of cirrhotic cases and decrease in the number of HCC cases in FD group, indicating delayed progression of HCC with FD. Moreover, FO led to more number of HCC and reduction in the number of cirrhotic cases, signifying early progression of HCC.

Derangement of hepatic polyamine, folate, and methionine cycle metabolism in cystathionine beta-synthase-deficient homocystinuria in the presence and absence of treatment: Possible implications for pathogenesis

Cystathionine beta-synthase deficient homocystinuria (HCU) is a life-threatening disorder of sulfur metabolism. Our knowledge of the metabolic changes induced in HCU are based almost exclusively on data derived from plasma. In the present study, we present a comprehensive analysis on the effects of HCU upon the hepatic metabolites and enzyme expression levels of the methionine-folate cycles in a mouse model of HCU.HCU induced a 10-fold increase in hepatic total homocysteine and in contrast to plasma, this metabolite was only lowered by approximately 20% by betaine treatment indicating that this toxic metabolite remains unacceptably elevated. Hepatic methionine, S-adenosylmethionine, S-adenosylhomocysteine, N-acetlymethionine, N-formylmethionine, methionine sulfoxide, S-methylcysteine, serine, N-acetylserine, taurocyamine and N-acetyltaurine levels were also significantly increased by HCU while cysteine, N-acetylcysteine and hypotaurine were all significantly decreased. In terms of polyamine metabolism, HCU significantly decreased spermine and spermidine levels while increasing 5′-methylthioadenosine. Betaine treatment restored normal spermine and spermidine levels but further increased 5′-methylthioadenosine.HCU induced a 2-fold induction in expression of both S-adenosylhomocysteine hydrolase and methylenetetrahydrofolate reductase. Induction of this latter enzyme was accompanied by a 10-fold accumulation of its product, 5-methyl-tetrahydrofolate, with the potential to significantly perturb one‑carbon metabolism. Expression of the cytoplasmic isoform of serine hydroxymethyltransferase was unaffected by HCU but the mitochondrial isoform was repressed indicating differential regulation of one‑carbon metabolism in different sub-cellular compartments. All HCU-induced changes in enzyme expression were completely reversed by either betaine or taurine treatment. Collectively, our data show significant alterations of polyamine, folate and methionine cycle metabolism in HCU hepatic tissues that in some cases, differ significantly from those observed in plasma, and have the potential to contribute to multiple aspects of pathogenesis.

Dietary Intakes of Folic Acid During Pregnancy Determines Maternal Re-Set of Metabolism Post-Birth in Wistar Rat Dams (FS08-06-19)

ObjectivesNutrition during pregnancy alters the “re-set” of maternal metabolism and in turn the mother’s metabolic phenotype later in life. Folic acid (FA, synthetic folate) consumed at intakes above requirements during pregnancy by rats leads to increased weight gain and altered DNA methylation in central and peripheral pathways regulating food intake. The objectives of this study were to examine the effects of intakes below and above FA dietary requirements on the re-set of energy metabolic pathways in Wistar rat mothers early post-birth. MethodsPregnant Wistar rats (n = 12/group) were fed an AIN93G diet with 5 levels of FA: 0X, 1X (control, 2 mg FA/kg), 2.5X, 5X or 10X. Dams were fed 1X-FA during lactation up to 1-week post-weaning (PW) when maternal metabolism is thought to re-set to homeostasis and then terminated. Weekly body weight, food intake, expression of hypothalamic food-intake neurons, mRNA and protein expression of folate-related and energy metabolic genes, and glucoregulatory hormones were measured. The homeostatic model assessment of insulin resistance (HOMA-IR) was used as a surrogate index of insulin resistance. ResultsBelow (0X) and above (5X and 10X) FA requirements during pregnancy suppressed expression of hepatic folate metabolism (methyltetrahydrofolate (MTHF) reductase, and methionine synthase; P < 0.05) genes and led to higher 5-MTHF (P < 0.005) in blood compared to control suggesting dysregulation of 1-carbon pathways. Dams fed 0X- and 5X-FA also had higher plasma insulin and HOMA-IR than controls and changes in glucose and lipid metabolism-regulating genes in muscle (Glucose transporter-4, and Peroxisome-proliferator activated receptors; P < 0.05) but not liver or adipose at 1-week PW. The diets did not affect expression of hypothalamic food intake neurons nor body weight or food intake of the dams from birth to 1-week PW. ConclusionsFA below (0X) or above (5X, 10X) requirements during pregnancy induce dysregulation of 1-carbon pathways and delay re-set of energy metabolic pathways in Wistar rat dams by 4-weeks after birth, potentially programming long-term negative metabolic effects. Funding SourcesThis research was supported by: Canadian Institute of Health Research, Institute of Nutrition, Metabolism and Diabetes (CIHR-INMD); EP supported by NSERC Alexander Graham Bell Canada Graduate Scholarships-Doctoral Program (CGS D).

The A2B Adenosine Receptor Antagonist Alloxazine Exacerbates NASH and Disrupts Cellular Folate Metabolism in Methionine and Choline Deficient Mice

Nonalcoholic fatty liver disease is characterized by hepatic lipid accumulation of greater than 5% and is a rising healthcare problem in the United States. Approximately 25–30% of the US population may have a fatty liver and 10–15% of these patients will progress to more severe disease known as nonalcoholic steatohepatitis (NASH). There are no approved treatments for NASH and the factors that result in the transition from fatty liver to NASH are not well defined. Folate and one‐carbon metabolism are implicated in the pathogenesis of NASH and are important pathways for the biosynthesis of many important molecules like creatine, phosphatidylcholine, purines, and thymidine. Additionally, the purine adenosine modulates immune cells by signaling to cell surface receptors on macrophages in the liver. In the present study, mice were fed a methionine and choline deficient diet to induce NASH lesions and treated with a putative A2B adenosine receptor antagonist, alloxazine, to probe the role of this adenosine receptor in NASH. MCD diet feeding reduced purine and thymidine nucleotides in the liver; potentially limiting the availability of crucial molecules for regeneration of liver tissue. MCD mice showed reduced activating transcription factor 4 (ATF4) expression, which has been shown to regulate mitochondrial folate metabolism and formate production which is required for purine biosynthesis. Alloxazine treatment exacerbated hepatic lipid accumulation and caused severe lobular inflammation in MCD mice. Alloxazine also disrupted hepatic folate metabolism and reduced the concentration of formate without altering concentrations of S‐adenosylmethionine and S‐adenosylhomocysteine. These data suggest that in addition to its function as an A2B adenosine receptor antagonist, alloxazine also impairs cellular folate metabolism. These data provide a novel link between folate and lipid metabolism, and inflammation in NASH.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

High-fat diet consumption reduces hepatic folate transporter expression via nuclear respiratory factor-1.

Folate is an essential micronutrient for biological function. The liver, a primary organ for folate metabolism and storage, plays an important role in folate homeostasis. Proton-coupled folate transporter (PCFT) and reduced folate carrier (RFC) are the major folate transporters responsible for folate uptake at basolateral membrane of hepatocytes. Low serum folate levels are frequently associated with obesity. We investigated the mechanism that regulated folate status in a mouse model with diet-induced obesity. Mice (C57BL/6J) were fed a high-fat diet (60% kcal fat) for 8weeks. Mice displayed increased hepatic lipid accumulation and decreased folate levels in the liver and serum compared to mice fed a normal chow diet (10% kcal fat). High-fat diet-fed mice had low expression of PCFT and RFC and decreased nuclear respiratory factor-1 (NRF-1)/DNA-binding activity. Treatment with NRF-1 siRNA or palmitic acid reduced folate transporter expression in hepatocytes. Inhibition of NRF-1 mediated folate transporter expression significantly reduced intracellular folate levels. These results suggest that chronic consumption of high-fat diets impairs folate transporter expression via NRF-1-dependent mechanism, leading to reduced hepatic folate storage. Understanding the regulation of folate homeostasis in obesity may have an important implication in current guideline of folate intake. KEY MESSAGES: Serum and liver folate levels are decreased in diet-induced obese mice. Chronic high-fat diet consumption impairs expression of hepatic PCFT and RFC. NRF-1 regulates hepatic folate transporters expression and folate levels.

Genetically determined folate deficiency is associated with abnormal hepatic folate profiles in the spontaneously hypertensive rat.

Increased levels of plasma cysteine are associated with obesity and metabolic disturbances. Our recent genetic analyses in spontaneously hypertensive rats (SHR) revealed a mutated Folr1 (folate receptor 1) as the quantitative trait gene associated with diminished renal Folr1 expression, lower plasma folate levels, hypercysteinemia, hyperhomocysteinemia and metabolic disturbances. To further analyse the effects of the Folr1 gene expression on folate metabolism, we used mass spectrometry to quantify folate profiles in the plasma and liver of an SHR-1 congenic strain, with wild type Folr1 allele on the SHR genetic background, and compared them with the SHR strain. In the plasma, concentration of 5-methyltetrahydrofolate (5mTHF) was significantly higher in SHR-1 congenic rats compared to SHR (60+/-6 vs. 42+/-2 nmol/l, P<0.01) and 5mTHF monoglutamate was the predominant form in both strains (>99 % of total folate). In the liver, SHR-1 congenic rats showed a significantly increased level of 5mTHF and decreased concentrations of dihydrofolate (DHF), tetrahydrofolate (THF) and formyl-THF when compared to the SHR strain. We also analysed the extent of folate glutamylation in the liver. Compared with the SHR strain, congenic wild-type Folr1 rats had significantly higher levels of 5mTHF monoglutamate. On the other hand, 5mTHF penta- and hexaglutamates were significantly higher in SHR when compared to SHR-1 rats. This inverse relationship of rat hepatic folate polyglutamate chain length and folate sufficiency was also true for other folate species. These results strongly indicate that the whole body homeostasis of folates is substantially impaired in SHR rats compared to the SHR-1 congenic strain and might be contributing to the associated metabolic disturbances observed in our previous studies.

A Black Cohosh Extract Causes Hematologic and Biochemical Changes Consistent with a Functional Cobalamin Deficiency in Female B6C3F1/N Mice.

Black cohosh rhizome, available as a dietary supplement, is most commonly marketed as a remedy for dysmenorrhea and menopausal symptoms. A previous subchronic toxicity study of black cohosh dried ethanolic extract (BCE) in female mice revealed a dose-dependent ineffective erythropoiesis with a macrocytosis consistent with the condition known as megaloblastic anemia. The purpose of this study was to investigate potential mechanisms by which BCE induces these particular hematological changes. B6C3F1/N female mice (32/group) were exposed by gavage to vehicle or 1,000 mg/kg BCE for 92 days. Blood samples were analyzed for hematology, renal and hepatic clinical chemistry, serum folate and cobalamin, red blood cell (RBC) folate, and plasma homocysteine and methylmalonic acid (MMA). Folate levels were measured in liver and kidney. Hematological changes included decreased RBC count; increased mean corpuscular volume; and decreased reticulocyte, white blood cell, neutrophil, and lymphocyte counts. Blood smear evaluation revealed increased Howell-Jolly bodies and occasional basophilic stippling in treated animals. Plasma homocysteine and MMA concentrations were increased in treated animals. Under the conditions of our study, BCE administration caused hematological and clinical chemistry changes consistent with a functional cobalamin, and possibly folate, deficiency. Further studies are needed to elucidate the mechanism by which BCE causes increases in homocysteine and MMA.

Disruption of redox homeostasis in liver function and activation of apoptosis on consumption of aspartame in folate deficient rat model

This study assesses the effect of long-term intake of aspartame on liver function and apoptosis signaling pathway in the Wistar albino rats. Several reports have suggested that methanol is one of the major metabolites of Aspartame. Non-primate animals are usually resistant to methanol-induced metabolic acidosis due to high levels of hepatic folate content; hence a folate deficiency model was induced by treating animals with methotrexate (MTX) prior to aspartame exposure. The aspartame treated MTX animals exhibited a marked significant increase in hepatic alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP) and lactic acid dehydrogenase (LDH) activity compared to controls. Aspartame treated MTX animals additionally exhibited down-regulation of genes namely B-cell lymphoma 2 (Bcl2) expression and up-regulation of Bcl-2-associated X protein (Bax), Fas-associated protein with death domain (FADD) and Caspase 3, 9 genes and apoptotic protein expression, indicating the augmentation of hepatic apoptosis. Nuclear condensation, micro vacuole formation in the cytoplasm and necrosis were observed in the liver of the aspartame treated animals on histopathology evaluation. Additionally, Immunohistochemical analysis revealed a significant increase in positive cells expressing Fas, FADD, Bax and Caspase 9 protein, indicating an increase in apoptotic protein expression in the liver. Thus, Aspartame may act as a chemical stressor which alters the functional status of liver, leading to hepatotoxicity.

Gene specific epigenetic regulation of hepatic folate transport system is responsible for perturbed cellular folate status during aging and exogenous modulation.

The present study was designed to identify the molecular mechanism of folate modulation and aging on aberrant liver folate transporter system. An in vivo rat model was used, in which weanling, young and adult rats were given folate deficient diet for 3 and 5 months and after 3 months of folate deficiency, one group received physiological folate repletion (2 mg/kg diet) and another group received over supplemented folate diet (8 mg/kg diet) for another 2 months. In adult group, 3 and 5 months of folate deficiency decreased serum and tissue folate levels with decreased uptake of folate, further associated with decreased expression levels of reduced folate carrier (RFC) and increased expression levels of folate exporter (ABCG2) at both mRNA and protein levels, which in turn regulated by promoter hypermethylation of RFC and promoter hypomethylation of ABCG2 gene. Promoter hypermethylation of RFC and promoter hypomethylation of ABCG2 may be attributed to the down regulation of RFC and up regulation of ABCG2 at mRNA and protein levels in conditions of 3 and 5 months of folate deficiency in the adult group.

Aspartame induced cardiac oxidative stress in Wistar albino rats

Abstract Aspartame (non-nutritive sweetener) is consumed by millions of people in products like beverages, instant breakfasts, desserts, breathe mints, sugar free chewing gum, vitamins, and pharmaceutical. On a weight basis, metabolism of aspartame generates approximately 50% phenylalanine, 40% aspartic acid and 10% methanol. The detailed mechanisms of their effects on cardiac tissue are still unclear. The present study aimed to clarify whether longer time aspartame consumption has any effect on heart of Wistar albino rats. Animals were randomly divided into 4 groups of 6 animals (group-1: control, group-2: folate deficient diet fed animals, group-3: control animals treated with aspartame, group-4: folate deficient diet fed animals treated with aspartame). Aspartame was given orally (40 mg/kg·bw/day), dissolved in normal saline and for 90 days. Since human beings have very low hepatic folate content, the folate deficient diet fed animals were used to mimic the human methanol metabolism. Aspartame consumption increased significantly plasma corticosterone level, suggesting that aspartame may act as a chemical stressor. There was a significant increase in lipid peroxidation, nitric oxide and protein carbonyl, and significant decrease in protein thiol, cardiac membrane bound ATPases (Na+, K+, Ca++, Mg++), enzymatic (SOD, CAT, GPX, G6PD, GR) and non-enzymatic antioxidants (GSH, Vit-C, Vit-E) as well as a significant increase in heart rate and heart marker enzymes (CK and CK-MB). It may be due to excessive generation of free radicals, which impairs cardiac function. Aspartame metabolite methanol or formaldehyde may be the causative factors behind these changes. However, up regulation of Hsp70 in immunohistochemical analysis of cardiac tissue might be a protective response to oxidative stress induced by aspartame metabolites and structural damages in cardiac tissue.

Effect of in ovo feeding of folic acid on the folate metabolism, immune function and epigenetic modification of immune effector molecules of broiler.

This study was conducted to investigate the effect of in ovo feeding (IOF) of folic acid on the folate metabolism, immune function and the involved epigenetic modification of broilers. A total of 400 (Cobb) hatching eggs were randomly divided into four groups (0, 50, 100 and 150 µg injection of folic acid at embryonic age 11 d), and chicks hatched from each treatment were randomly divided into six replicates with 12 broilers/replicate after incubation. The results indicated that, in ovo, 100- and 150-µg folic acid injections improved the hatchability. The average daily gain and feed conversion ratio increased in the 150-µg group during the late growth stage. Simultaneously, in the 100- and 150-µg groups, an increase was observed in hepatic folate content and the expression of methylenetetrahydrofolate reductase (d1 and 42) and methionine synthase reductase (d21). IgG and IgM concentrations, as well as plasma lysozyme activity of broilers, showed a marked increase along with increasing folic acid levels. The splenic expression levels of IL-2 and IL-4 were up-regulated, whereas that of IL-6 was down-regulated, in the 100- and 150-µg folic acid treatment groups. In addition, histone methylation in IL-2 and IL-4 promoters exhibited an enrichment of H3K4m2 but a loss of H3K9me2 with the increased amount of folic acid additive. In contrast, a decrease in H3K4m2 and an increase in H3K9me2 were observed in the IL-6 promoter in folic acid treatments. Furthermore, in ovo, the 150-µg folic acid injection improved the chromatin tightness of the IL-2 and IL-4 promoter regions. Our findings suggest that IOF of 150 µg of folic acid can improve the growth performance and folate metabolism of broilers, and enhance the relationship between immune function and epigenetic regulation of immune genes, which are involved with the alterations in chromatin conformation and histone methylation in their promoters.

Effects of excessive dietary methionine on oxidative stress and dyslipidemia in chronic ethanol-treated rats.

BACKGROUND/OBJECTIVEThe aim of this study was to examine the effect of high dietary methionine (Met) consumption on plasma and hepatic oxidative stress and dyslipidemia in chronic ethanol fed rats.MATERIALS/METHODSMale Wistar rats were fed control or ethanol-containing liquid diets supplemented without (E group) or with DL-Met at 0.6% (EM1 group) or 0.8% (EM2 group) for five weeks. Plasma aminothiols, lipids, malondialdehyde (MDA), alanine aminotransferase (ALT), and aspartate aminotransferase were measured. Hepatic folate, S-adenosylmethionine (SAM), and S-adenosylhomocysteine (SAH) were measured.RESULTSDL-Met supplementation was found to increase plasma levels of homocysteine (Hcy), triglyceride (TG), total cholesterol (TC), and MDA compared to rats fed ethanol alone and decrease plasma ALT. However, DL-Met supplementation did not significantly change plasma levels of HDL-cholesterol, cysteine, cysteinylglycine, and glutathione. In addition, DL-Met supplementation increased hepatic levels of folate, SAM, SAH, and SAM:SAH ratio. Our data showed that DL-Met supplementation can increase plasma oxidative stress and atherogenic effects by elevating plasma Hcy, TG, and TC in ethanol-fed rats.CONCLUSIONThe present results demonstrate that Met supplementation increases plasma oxidative stress and atherogenic effects by inducing dyslipidemia and hyperhomocysteinemia in ethanol-fed rats.

Folate deficiency in rat pups during weaning causes learning and memory deficits.

Folate is essential for fetal development, and its deficiency during gestation causes behavioural deficits in the offspring. The present study investigated its influence during weaning on brain function in the pups of rats that were put on a folate-deficient (FD) diet on postnatal day (PND) 1. Systemic folate deficiency in pups on the FD diet (n 15) was evident from the dramatically lower hepatic folate concentrations (median 23·7, range 8·1-48·4 ng/mg protein) and higher homocysteine concentrations (median 27·7, range 14·7-45·5 pmol/mg protein), respectively, compared with those of pups on the normal diet (ND; n 9) (median 114·5, range 64·5-158·5 ng/mg protein and median 15·5, range 11·6-18·9 pmol/mg protein) on PND 23. Brain folate concentrations although low were similar in pups on the FD diet (median 10·5, range 5·5-24·5 ng/mg protein) and ND (median 11·1, range 7·1-24·2 ng/mg protein). There was a high accumulation of homocysteine in the brain of FD pups, mostly in the hippocampus (median 58·1, range 40·8-99·7 pmol/mg protein) and cerebellum (median 69·1, range 50·8-126·6 pmol/mg protein), indicating metabolic folate deficiency despite normal brain folate concentrations. Developmental deficits or autistic traits were more frequent in the FD group than in the ND group and repetitive self-grooming occurred, on average, three times (range 1-8) v. once (range 0-3) during 5 min, respectively. Long-term memory or spatial learning and set-shifting deficits affected 12 to 62% of rats in the FD group compared with none in the ND group. Post-weaning folic acid supplementation did not correct these deficits. These observations indicate that folate deficiency during weaning affects postnatal development even when gestational folate supply is normal.

Dietary l-methionine supplementation mitigates gamma-radiation induced global DNA hypomethylation: Enhanced metabolic flux towards S-adenosyl-l-methionine (SAM) biosynthesis increases genomic methylation potential

The objective of this study was to examine the effect of 60Co-gamma (γ) radiation on modulation of genomic DNA methylation, if any, of mice maintained (6weeks) on normal control diet (NCD) and l-methionine supplemented diet (MSD). To elucidate the possible underlying mechanism(s), we exposed the animals to γ-radiation (2, 3 and 4Gy) and investigated the profile of downstream metabolites and enzymes involved in S-adenosyl-l-methionine (SAM) generation. Liver samples were also subjected to histopathological examinations. Compared to NCD fed and irradiated animals, hepatic folate, choline and l-methionine levels decreased moderately, while hepatic SAM levels increased in MSD fed and irradiated animals. Under these conditions, a marked modulation of methionine adenosyltransferase (MAT) and l-methionine synthase (MSase) activities was observed. Concomitant with increase in liver SAM pool, increased DNA methyltransferase (dnmt) activity in MSD fed mice indicated enhanced metabolic flux towards DNA methylation. Further results showed that genomic DNA methylation and 5-methyl-2′-deoxy cytidine residues were maintained at normal levels in MSD fed and irradiated mice compared to NCD fed and irradiated animals. In conclusion, our results suggest that increasing supply of preformed methyl groups, via dietary l-methionine supplementation might significantly increase methylation potential of radiation stress compromised DNA methylation cycle.

Vitamin B12 and Folic Acid Imbalance Modifies NK Cytotoxicity, Lymphocytes B and Lymphoprolipheration in Aged Rats

Different vitamin B12 and folic acid concentrations could exacerbate the immune response. The aim was to evaluate different dietary folic acid and vitamin B12 levels on the immune response in aged rats. Male Sprague Dawley aged rats were assigned to three folic acid groups (deficient, control, supplemented) each in absence of vitamin B12 for 30 days. Several parameters of innate and acquired immune responses were measured. Serum and hepatic folate levels increased according to folic acid dietary level, while vitamin B12 levels decreased. There was a significant decrease in natural killer cell-mediated cytotoxicity in the spleen for the vitamin B12 deficient diet and folic acid control diet groups. Significant changes in CD45 lymphocyte subsets were also observed according to dietary imbalance. Lymphoproliferative response to concanavalin A and phytohemagglutinin did not differ significantly between groups. The spleen response to lipopolysaccharide increased significantly, but was unmodified for the other organs. An imbalance between dietary vitamin B12 and folic acid concentrations alters some immunological parameters in aged rats. Therefore, the ratio between folate and vitamin B12 could be as important as their absolute dietary concentrations.

Vitamin D is not linked to folate status and mRNA expression of intestinal proton-coupled folate transporter

In vitro studies discovered intestinal proton-coupled folate transporter (PCFT) as a vitamin D hormone-responsive gene. In vivo effects of vitamin D on PCFT and folate status are currently not available. Three experiments were conducted. At first, vitamin D receptor knockout (VDR(-/-)) mice and corresponding wild-type (WT) mice were compared for their plasma and hepatic folate concentration and PCFT mRNA expression in intestinal mucosa. In a second experiment with rats, we analyzed the folate status of offspring in response to a maternal vitamin D-adequate (1,000IU/kg) or vitamin D-deficient (0IU/kg) diet that was fed for 11weeks. Finally, the plasma folate concentration of healthy individuals was studied at baseline (in winter) and in response to an oral treatment for 8weeks with 2,000IU vitamin D3 per day or a placebo, respectively. Here, we show that folate status and intestinal PCFT mRNA abundance did not differ between the VDR(-/-) and the WT mice. No effect of vitamin D on folate status was also found in rat dams and their offspring, and plasma folate levels of individuals did not change in response to vitamin D. Current data from studies with model animals and humans provide no indication for a vitamin D effect on intestinal uptake and status of folate.

Maternal folic acid–deficient diet causes congenital malformations in the mouse eye

The eye is a very complex structure derived from the neural tube, surface ectoderm, and migratory mesenchyme from a neural crest origin. Because structures that evolve from the neural tube may be affected by a folate/folic acid (FA) deficiency, the aim of this work was to investigate whether a maternal folic acid-deficient diet may cause developmental alterations in the mouse eye. Female C57BL/6J mice (8 weeks old) were assigned into two different folic acid groups for periods ranging between 2 and 16 weeks. Animals were killed at gestation day 17. Hepatic folate was analyzed, and the eyes from 287 fetuses were macroscopically studied, sectioned and immunolabeled with anti-transforming growth factor (TGF)-β2 and anti-TGF-βRII. Mice exposed to a FA-deficient diet exhibited numerous eye macroscopic anomalies, such as anophthalmia and microphthalmia. Microscopically, the eye was the most affected organ (43.7% of the fetuses). The highest incidence of malformations occurred from the 8th week onward. A statistically significant linear association between the number of maternal weeks on the FA-deficient diet and embryonic microscopic eye malformations was observed. The optic cup derivatives and structures forming the eye anterior segment showed severe abnormalities. In addition, TGF-β2 and TGF-βRII expression in the eye was also altered. This study suggests that an adequate folic acid/folate status plays a key role in the formation of ocular tissues and structures, whereas a vitamin deficiency is negatively associated with a normal eye development even after a short-term exposure.