Guanidinoacetic Acid and Creatine are Associated with Cardiometabolic Risk Factors in Healthy Men and Women: A Cross-Sectional Study

Food-sourced guanidinoacetic acid and methylation cycle biomarkers in individuals aged one year and older: a population-based cross-sectional study

PURPOSE

Several preliminary studies suggest dietary guanidinoacetic acid (GAA) might impact methyl group availability and/or methylation biomarkers, fueling ongoing debates. This study aimed to explore the relationship between dietary GAA intake and plasma indicators of the methylation cycle in individuals aged one year and older, using data from the 2001-2002 National Health and Nutrition Examination Survey (NHANES).

METHODS

Dietary information was obtained from individuals who completed a 24-hour Dietary Recall, with total daily intake of GAA calculated by aggregating all relevant food items. Relevant variables related to the methylation cycle, such as red blood cell (RBC) folate and serum folate, vitamin B12, total homocysteine (tHCy), and methylmalonic acid (MMA), were identified from the NHANES 2001-2002 laboratory assessments.

RESULTS

A total of 9,115 individuals (51.3% females) were included in the final analysis. Linear regression unveiled a significant association between higher GAA intake and diminished RBC folate (p < 0.001), serum folate (p < 0.001), and MMA levels (p = 0.007). It also revealed an elevation in tHCy levels with increased GAA intake (p < 0.001). These associations remained significant even after adjusting for demographic variables and dietary factors pertinent to the methylation cycle (p < 0.05).

CONCLUSION

Our findings suggest that dietary exposure to GAA (resulting in conversion to creatine) could be considered a nutritional factor associated with the consumption of methyl groups in the general population.

Comparative effects of dietary herbal mixture or guanidinoacetic acid supplementation on growth performance, cecal microbiota, blood profile, excreta gas emission, and meat quality in Hanhyup-3-ho chicken

Phytogenic feed additives are renowned for their growth promotion, gut health enhancement, and disease prevention properties, which is important factors for sustaining prolonged poultry rearing. The study aimed to evaluate the effect of herbal mixture (mixture of ginseng and artichoke) or guanidinoacetic acid (GAA) on growth performance, cecal microbiota, excretal gas emission, blood profile, and meat quality in Hanhyup-3-ho chicken. A total of 360 one-day-old chickens (half males and half females) were allocated into one of 3 dietary treatments (12 replicate cages/treatment; 10 broilers/replicate cage) for 100 d of age. Experimental diets were CON: basal diet; TRT1: basal diet combined with 0.05% herbal mixture; and TRT2: basal diet combined with 0.06% GAA. All birds received a basal diet during the first 30 d, but from d 31 to 100, an experimental diet was supplied. The addition of 0.05% herbal mixture improved the average body weight gain and feed conversion ratio from d 31 to 100 as well as the overall experimental period. The cecal Lactobacillus, Escherichia coli, and Salmonella count remained consistent across all dietary treatments. Blood albumin and Superoxide Dismutase (SOD) levels increased in the herbal mixture supplemented diet. Additionally, there was a notable reduction in excretal NH3 and H2S emissions in the herbal mixture group. Furthermore, the herbal mixture group exhibited increased breast muscle weight, improved breast muscle color, improved water holding capacity, and a decrease in abdominal fat compared to the control group. Additionally, the supplementation of 0.06% GAA did not demonstrate any statistically significant impact on any evaluated parameter throughout the experiment. The results from the present investigation underscore the potential of ginseng together with artichoke extract supplementation as a viable feed additive, conferring improvements in growth performance, feed efficiency, excreta gas emission, meat quality parameters, and defense mechanism against oxidative stress in Hanhyup-3-ho chicken.

Metabolomics and Lipidomics Signatures of Insulin Resistance and Abdominal Fat Depots in People Living with Obesity

The liver, skeletal muscle, and adipose tissue are major insulin target tissues and key players in glucose homeostasis. We and others have described diverse insulin resistance (IR) phenotypes in people at risk of developing type 2 diabetes. It is postulated that identifying the IR phenotype in a patient may guide the treatment or the prevention strategy for better health outcomes in populations at risk. Here, we performed plasma metabolomics and lipidomics in a cohort of men and women living with obesity not complicated by diabetes (mean [SD] BMI 36.0 [4.5] kg/m2, n = 62) to identify plasma signatures of metabolites and lipids that align with phenotypes of IR (muscle, liver, or adipose tissue) and abdominal fat depots. We used 2-step hyperinsulinemic-euglycemic clamp with deuterated glucose, oral glucose tolerance test, dual-energy X-ray absorptiometry and abdominal magnetic resonance imaging to assess muscle-, liver- and adipose tissue- IR, beta cell function, body composition, abdominal fat distribution and liver fat, respectively. Spearman’s rank correlation analyses that passed the Benjamini−Hochberg statistical correction revealed that cytidine, gamma-aminobutyric acid, anandamide, and citrate corresponded uniquely with muscle IR, tryptophan, cAMP and phosphocholine corresponded uniquely with liver IR and phenylpyruvate and hydroxy-isocaproic acid corresponded uniquely with adipose tissue IR (p < 7.2 × 10−4). Plasma cholesteryl sulfate (p = 0.00029) and guanidinoacetic acid (p = 0.0001) differentiated between visceral and subcutaneous adiposity, while homogentisate correlated uniquely with liver fat (p = 0.00035). Our findings may help identify diverse insulin resistance and adiposity phenotypes and enable targeted treatments in people living with obesity.

Homoarginine in the cardiovascular system: Pathophysiology and recent developments

Upcoming experimental and epidemiological data have identified the endogenous non-proteinogenic amino acid L-homoarginine (L-hArg) not only as a novel biomarker for cardiovascular disease but also as being directly involved in the pathogenesis of cardiac dysfunction. The association of low L-hArg levels with adverse cardiovascular events and mortality has proposed the idea of nutritional supplementation to rescue pathways inversely associated with cardiovascular health. Subsequent clinical and experimental studies contributed significantly to our knowledge of potential effects on the cardiorenal axis, acting either as a biomarker or a cardiovascular active agent. In this review article, we provide a comprehensive summary of the L-hArg metabolism, pathophysiological aspects, and current developments in the field of experimental and clinical evidence in favor of protective cardiovascular effects. Establishing a reliable biomarker to identify patients at high risk to die of cardiovascular disease represents one of the main goals for tackling this disease and providing individual therapeutic guidance.

A metabolome-wide association study of in utero metal and trace element exposures with cord blood metabolome profile: Findings from the Boston Birth Cohort

BACKGROUND

Exposure to metals lead (Pb), mercury (Hg), and cadmium (Cd) and trace elements selenium (Se) and manganese (Mn) has been linked to the developmental origins of cardiometabolic diseases, but the mechanisms are not well-understood.

OBJECTIVE

Conduct a metabolome-wide association study to understand how in utero exposure to Pb, Hg, Cd, Se, and Mn affects the metabolic programming of fetuses.

METHODS

We used data from the Boston Birth Cohort, which enrolled mother-child pairs from Boston, MA. We measured metals and trace elements in maternal red blood cells (RBCs) collected 24-72 h after delivery, and metabolites in cord blood collected at birth. We used multivariable linear regression to examine associations of metals and trace elements with metabolites and Bonferroni correction to account for multiple comparisons. We assessed non-linear associations of metals and trace elements with metabolites using restricted cubic spline plots.

RESULTS

This analysis included 670 mother-child pairs (57% non-Hispanic Black and 24% Hispanic). After Bonferroni correction, there were 25 cord metabolites associated with at least one of the metals or trace elements. Pb was negatively associated with the xenobiotic piperine, Cd was positively associated with xenobiotics cotinine and hydroxycotinine, and Hg was associated with 8 lipid metabolites (in both directions). Se and Mn shared associations with 6 metabolites (in both directions), which mostly included nucleotides and amino acids; Se was additionally associated with 7 metabolites (mostly amino acids, nucleotides, and carnitines) and Mn was additionally associated with C36:4 hydroxy phosphatidylcholine. Restricted cubic spline plots showed that most associations were linear.

DISCUSSION

Maternal RBC metal and trace element concentrations were associated in a dose-dependent fashion with cord blood metabolites. What remains to be determined is whether these metals- and trace elements-associated changes in cord metabolites can influence a child's risk of cardiometabolic diseases.

Multiplatform metabolomics for an integrative exploration of metabolic syndrome in older men

BACKGROUND

Metabolic syndrome (MetS), a cluster of factors associated with risks of developing cardiovascular diseases, is a public health concern because of its growing prevalence. Considering the combination of concomitant components, their development and severity, MetS phenotypes are largely heterogeneous, inducing disparity in diagnosis.

METHODS

A case/control study was designed within the NuAge longitudinal cohort on aging. From a 3-year follow-up of 123 stable individuals, we present a deep phenotyping approach based on a multiplatform metabolomics and lipidomics untargeted strategy to better characterize metabolic perturbations in MetS and define a comprehensive MetS signature stable over time in older men.

FINDINGS

We characterize significant changes associated with MetS, involving modulations of 476 metabolites and lipids, and representing 16% of the detected serum metabolome/lipidome. These results revealed a systemic alteration of metabolism, involving various metabolic pathways (urea cycle, amino-acid, sphingo- and glycerophospholipid, and sugar metabolisms…) not only intrinsically interrelated, but also reflecting environmental factors (nutrition, microbiota, physical activity…).

INTERPRETATION

These findings allowed identifying a comprehensive MetS signature, reduced to 26 metabolites for future translation into clinical applications for better diagnosing MetS.

FUNDING

The NuAge Study was supported by a research grant from the Canadian Institutes of Health Research (CIHR; MOP-62842). The actual NuAge Database and Biobank, containing data and biologic samples of 1,753 NuAge participants (from the initial 1,793 participants), are supported by the Fonds de recherche du Québec (FRQ; 2020-VICO-279753), the Quebec Network for Research on Aging, a thematic network funded by the Fonds de Recherche du Québec - Santé (FRQS) and by the Merck-Frost Chair funded by La Fondation de l'Université de Sherbrooke. All metabolomics and lipidomics analyses were funded and performed within the metaboHUB French infrastructure (ANR-INBS-0010). All authors had full access to the full data in the study and accept responsibility to submit for publication.

Obesity Connected Metabolic Changes in Type 2 Diabetic Patients Treated With Metformin

Metformin is widely used in the treatment of Type 2 Diabetes Mellitus (T2DM). However, it is known to have beneficial effects in many other conditions, including obesity and cancer. In this study, we aimed to investigate the metabolic effect of metformin in T2DM and its impact on obesity. A mass spectrometry (MS)-based metabolomics approach was used to analyze samples from two cohorts, including healthy lean and obese control, and lean as well as obese T2DM patients on metformin regimen in the last 6 months. The results show a clear group separation and sample clustering between the study groups due to both T2DM and metformin administration. Seventy-one metabolites were dysregulated in diabetic obese patients (30 up-regulated and 41 down-regulated), and their levels were unchanged with metformin administration. However, 30 metabolites were dysregulated (21 were up-regulated and 9 were down-regulated) and then restored to obese control levels by metformin administration in obese diabetic patients. Furthermore, in obese diabetic patients, the level of 10 metabolites was dysregulated only after metformin administration. Most of these dysregulated metabolites were dipeptides, aliphatic amino acids, nucleic acid derivatives, and urea cycle components. The metabolic pattern of 62 metabolites was persistent, and their levels were affected by neither T2DM nor metformin in obesity. Interestingly, 9 metabolites were significantly dysregulated between lean and obese cohorts due to T2DM and metformin regardless of the obesity status. These include arginine, citrulline, guanidoacetic acid, proline, alanine, taurine, 5-hydroxyindoleacetic acid, and 5-hydroxymethyluracil. Understanding the metabolic alterations taking place upon metformin treatment would shed light on possible molecular targets of metformin, especially in conditions like T2DM and obesity.

Risk of Adverse Outcomes in Females Taking Oral Creatine Monohydrate: A Systematic Review and Meta-Analysis

Creatine Monohydrate (CrM) is a dietary supplement routinely used as an ergogenic aid for sport and training, and as a potential therapeutic aid to augment different disease processes. Despite its increased use in recent years, studies reporting potential adverse outcomes of CrM have been mostly derived from male or mixed sex populations. A systematic search was conducted, which included female participants on CrM, where adverse outcomes were reported, with meta-analysis performed where appropriate. Six hundred and fifty-six studies were identified where creatine supplementation was the primary intervention; fifty-eight were female only studies (9%). Twenty-nine studies monitored for adverse outcomes, with 951 participants. There were no deaths or serious adverse outcomes reported. There were no significant differences in total adverse events, (risk ratio (RR) 1.24 (95% CI 0.51, 2.98)), gastrointestinal events, (RR 1.09 (95% CI 0.53, 2.24)), or weight gain, (mean difference (MD) 1.24 kg pre-intervention, (95% CI -0.34, 2.82)) to 1.37 kg post-intervention (95% CI -0.50, 3.23)), in CrM supplemented females, when stratified by dosing regimen and subject to meta-analysis. No statistically significant difference was reported in measures of renal or hepatic function. In conclusion, mortality and serious adverse events are not associated with CrM supplementation in females. Nor does the use of creatine supplementation increase the risk of total adverse outcomes, weight gain or renal and hepatic complications in females. However, all future studies of creatine supplementation in females should consider surveillance and comprehensive reporting of adverse outcomes to better inform participants and health professionals involved in future trials.

Is Homoarginine a Protective Cardiovascular Risk Factor?

A series of recent epidemiological studies have implicated the endogenous nonproteinogenic amino acid l-homoarginine as a novel candidate cardiovascular risk factor. The association between homoarginine levels and the risk of adverse cardiovascular outcomes is inverse (ie, high cardiovascular risk is predicted by low rather than high homoarginine levels), which makes it plausible to normalize systemic homoarginine levels via oral supplementation. The emergence of homoarginine as a potentially treatable protective cardiovascular risk factor has generated a wave of hope in the field of cardiovascular prevention. Herein, we review the biochemistry, physiology, and metabolism of homoarginine, summarize the strengths and weaknesses of the epidemiological evidence linking homoarginine to cardiovascular disease and its potential protective cardiovascular effects, and identify priorities for future research needed to define the clinical utility of homoarginine as a prognostic factor and therapeutic target in cardiovascular disease.

Age-Related Changes in Serum Guanidinoacetic Acid in Women

Guanidinoacetic acid (GAA) is a fundamental intermediate in cellular bioenergetics, with circulating levels of GAA often reflects disturbances in its conversion due to many intrinsic and extrinsic factors, including gender or age. Here, we evaluated serum GAA in 172 healthy women aged 18 to 65 years, with age found to significantly predict serum GAA concentrations (r=0.29; P=0.03). This perhaps nominates serum GAA as a novel gender-specific proxy of impaired bioenergetics with aging.

Elevated uric acid levels in premenopausal female systemic lupus erythematosus patients: Association with potential or existing renal damage

Do premenopausal female systemic lupus erythematosus (SLE) patients have a low incidence of hyperuricaemia (HU) as healthy premenopausal females? As of yet, there have been few studies. This study aims to investigate the serum uric acid (UA) levels of premenopausal female SLE patients and the associated clinical risk factors. 107 premenopausal female SLE patients were divided into two groups: the high UA SLE group (n = 45) and the normal UA SLE group (n = 62). In total, 50 age-matched healthy premenopausal females served as the control group. Serum UA concentration, kidney damage index, lupus index, disease activity score of lupus and serum lipid index were collected and compared between the SLE subgroups. Binary logistic regression and multiple linear regression analyses were used to analyse the association of high UA levels with clinical features. The mean UA level of the SLE group was significantly higher than that of the control group (509.73 ± 150.28 μmol/L vs 296.78 ± 69.87 μmol/L, P < 0.001), as was the incidence of HU (42.06% vs 14.00%, P = 0.01). The UA levels of the high UA SLE group and the normal UA SLE group were 515.91 ± 120.64 μmol/L and 245.71 ± 63.18 μmol/L, respectively, which was statistically significant ( P < 0.001). None of the patients with HU had current or previous gout attacks. The frequency of patients with renal manifestations in the high UA SLE group was significantly higher than that in the normal UA SLE group (χ2 = 26.278, P < 0.001). In the SLE group, the medications azathioprine and cyclosporine were not associated with HU ( P = 0.689), as analysed by binary linear regression. Using multiple linear regression analysis, it was found that urinary blood ( P = 0.048), creatinine ( P = 0.016), triglycerides ( P = 0.029), peripheral white blood cells ( P = 0.007) and renal manifestation ( P < 0.001) were associated with HU in the SLE group. Our results demonstrate that premenopausal SLE patients had higher levels of UA than healthy premenopausal females, which may be associated with potential or existing renal damage.