Effects of amino acid derivatives on physical, mental, and physiological activities

Red Meat Amino Acids for Beginners: A Narrative Review

Meat is a major source of dietary protein and fat across the globe. Red and white meat are the major terms consumers use to refer to types of meat; however, these terms do not fully encompass the range of nutrients provided by meat sources. Red meat refers to meat from mammalian skeletal muscle, while white meat refers to poultry. Red and white meat both provide a wide range of nutritional components in the context of fatty acids, amino acids and micronutrients. Importantly, it has been demonstrated that amino acid profiles differ between red meat and white meat as well as between different sources of red meat. Red meat is a complete source of dietary amino acids, meaning it contains all essential amino acids (EAAs), and in addition, it contains all the non-essential amino acids (NEAAs). Red meat is also the most abundant source of bioavailable heme-iron essential for muscle growth and cardiovascular health. Red meat has been indicated as a major contributor to the rising incidence of metabolic disorders and even colorectal cancer. However, it is important to note that while red meat consumption is linked to these conditions, it is typically the overconsumption of red meat that is associated with obesity and other metabolic symptoms. Similarly, the preparation of red meat is a key factor in its link to colorectal cancer as some methods of preparation produce carcinogens while others do not. Finally, red meat may also be situationally more beneficial to some groups than others, particularly in the cases of sex and aging. For pregnant women, increases in red meat consumption may be beneficial to increase the intake of semi-essential amino acids, while in the elderly, increases in red meat consumption may better preserve muscle mass compared with other dietary protein sources.

Flexible Semi-synthesis of UFM11-82-Propargylamine by Aminolysis with Valine-Propargylamine

We report a novel semi-synthetic strategy of UFM11-82-propargylamine by N-S acyl transfer to give UFM11-80R thioester and subsequent aminolysis with valine-propargylamine. The use of the valine-propargylamine molecule overcomes the inability of the valine site to efficiently undergo the N-S acyl transfer. This strategy benefits from the availability of raw materials for bulk expression, and the resulting probe shows high selectivity toward UFM1-specific proteases in buffers and cell lysates.

Targeted and non-targeted metabolic characteristics of 6,7-dihydroxy-2,4- dimethoxyphenanthrene during simulated gastrointestinal digestion

6,7-dihydroxy-2,4-dimethoxyphenanthrene (PC4), isolated and identified from Chinese yam, was one of the important characteristic active ingredients. The present study established simulated gastrointestinal digestion and caco-2 intestinal epithelial models to investigate the digestive and metabolic characteristics of PC4. The results indicated that PC4 was mainly digested and metabolized in the intestine, with a digestion rate of 94 %, producing active characteristic metabolites including 2,6-dimethoxy-4-phenanthrenol (MC1) and 1-methoxyphenanthrene (MC2). Molecular docking indicated that the COX-2 enzyme inhibitory activity of MC1 might be superior to that of the prototype PC4. During 24 h co-incubation of PC4 with caco-2 monolayer epithelial, the signal pathway related to lipid decomposition was up-regulated within 0-12 h, while the diabetes complications AGE-RAGE was inhibited just in 0-6 h period significantly. The research database provided scientific basis for the digestion and metabolism of PC4, and laid theoretical foundation for the scientific development of Chinese yam functional foods.

Multi-Omics Revealed Resveratrol and β-Hydroxy-β-methyl Butyric Acid Alone or in Combination Improved the Jejunal Function in Tibetan Sheep

Previous research studies confirmed that both resveratrol (RES) and β-hydroxy-β-methyl butyric acid (HMB) improved growth performance by altering intestinal microbiota. However, the mechanism underlying of RES and HMB on intestinal function remains unclear in ruminant. In this study, supplements of RES and HMB alone or in combination were evaluated as promoters of antioxidant capacity, immune response and barrier function, and modulators of the microbiota and metabolite profiles in the jejunum of Tibetan sheep. A total of 120 two-month-old Tibetan rams were randomly divided into four treatments (n = 30 per treatment), which were supplemented with a basal diet with 1.5 g RES/d (RES group), 1.25 g HMB/d (HMB group), 1.5 g RES/d plus 1.25 g HMB/d (RES-HMB group), and without additions (Control group). The results showed that RES and HMB improved the antioxidant capacity (CAT, GSH-Px, SOD, and T-AOC), immunity (IgA, IgG, and IgM), and digestive enzyme activity (α-amylase, lipase, and chymotrypsin) of the experimental lambs (p < 0.05). Additionally, jejunal morphology including villus width, villus height, and muscle layer thickness exhibited a significant difference when rams were fed diets supplemented with RES and HMB (p < 0.05). Furthermore, the determination of fermentation parameters showed that the butyrate concentration in the RES-HMB group was greater than those in the C and RES groups (p < 0.05). When compared to the C group, barrier-related gene expression (MUC-2, ZO-1, and IL-10) was significantly increased in the RES-HMB group (p < 0.05). Dietary RES and (or) HMB supplementation significantly increased the abundance of Methanobrevibacter, Actinobacteriota and Bacillus (p < 0.05). The abundance of differential bacteria was positively associated with butyrate concentration (p < 0.05). Metabolome analysis revealed that alpha ketoglutarate, succinic semialdehyde, and diacetyl as well as butanoate metabolism pathways connected to the improvements in butyrate concentration by RES and (or) HMB supplementation. Collectively, our results suggested that RES and (or) HMB supplementation improved butyrate concentration via regulating the microbial community (Methanobrevibacter, Actinobacteriota and Bacillus) and metabolism (alpha ketoglutarate, succinic semialdehyde, and diacetyl), thus contributing to jejunal morphology, antioxidant capacity, immune response, digestive enzyme activity, and barrier function.

An Amino Acid Mixture to Counteract Skeletal Muscle Atrophy: Impact on Mitochondrial Bioenergetics

Skeletal muscle atrophy (SMA) is caused by a rise in muscle breakdown and a decline in protein synthesis, with a consequent loss of mass and function. This study characterized the effect of an amino acid mixture (AA) in models of SMA, focusing on mitochondria. C57/Bl6 mice underwent immobilization of one hindlimb (I) or cardiotoxin-induced muscle injury (C) and were compared with controls (CTRL). Mice were then administered AA in drinking water for 10 days and compared to a placebo group. With respect to CTRL, I and C reduced running time and distance, along with grip strength; however, the reduction was prevented by AA. Tibialis anterior (TA) muscles were used for histology and mitochondria isolation. I and C resulted in TA atrophy, characterized by a reduction in both wet weight and TA/body weight ratio and smaller myofibers than those of CTRL. Interestingly, these alterations were lightly observed in mice treated with AA. The mitochondrial yield from the TA of I and C mice was lower than that of CTRL but not in AA-treated mice. AA also preserved mitochondrial bioenergetics in TA muscle from I and C mice. To conclude, this study demonstrates that AA prevents loss of muscle mass and function in SMA by protecting mitochondria.

The microbiota-gut-brain axis: A crucial immunomodulatory pathway for Bifidobacterium animalis subsp. lactis' resilience against LPS treatment in neonatal rats

An imbalanced gut microflora may contribute to immune disorders in neonates due to an immature gut barrier. Bacterial toxins, particularly, can trigger the immune system, potentially resulting in uncontrolled gut and systemic inflammation. Previous research has revealed that Bifidobacterium animalis subsp. lactis (B. lactis) could protect against early-life pathogen infections by enhancing the gut barrier. However, the effects of B. lactis on a compromised immune system remain uncertain. Hence, this study concentrated on the immunomodulatory effects and mechanisms of B. lactis in neonatal rats intraperitoneally injected with lipopolysaccharide (LPS), a bacterial toxin and inflammatory mediator. First, B. lactis significantly alleviated the adverse effects induced by LPS on the growth, development, and body temperature of neonatal rats. Second, B. lactis significantly reduced the immune responses and damage induced by LPS, affecting both systemic and local immune responses in the peripheral blood, gut, and brain. Notably, B. lactis exhibited extra potent neuroprotective and neurorepair effects. Our research found that pre-treatment with B. lactis shaped the diverse gut microecology by altering both microbial populations and metabolic biomolecules, closely linked to immunomodulation. Overall, this study elucidated the multifaceted roles of B. lactis in neonatal hosts against pathogenic infection and immune disorder, revealing the existence of the microbiota-gut-brain axis.

Antibacterial Ingredients and Modes of the Methanol-Phase Extract from the Fruit of Amomum villosum Lour

Epidemics of infectious diseases threaten human health and society stability. Pharmacophagous plants are rich in bioactive compounds that constitute a safe drug library for antimicrobial agents. In this study, we have deciphered for the first time antibacterial ingredients and modes of the methanol-phase extract (MPE) from the fruit of Amomum villosum Lour. The results have revealed that the antibacterial rate of the MPE was 63.64%, targeting 22 species of common pathogenic bacteria. The MPE was further purified by high performance liquid chromatography (Prep-HPLC), and three different constituents (Fractions 1-3) were obtained. Of these, the Fraction 2 treatment significantly increased the cell membrane fluidity and permeability, reduced the cell surface hydrophobicity, and damaged the integrity of the cell structure, leading to the leakage of cellular macromolecules of Gram-positive and Gram-negative pathogens (p < 0.05). Eighty-nine compounds in Fraction 2 were identified by ultra HPLC-mass spectrometry (UHPLC-MS) analysis, among which 4-hydroxyphenylacetylglutamic acid accounted for the highest 30.89%, followed by lubiprostone (11.86%), miltirone (10.68%), and oleic acid (10.58%). Comparative transcriptomics analysis revealed significantly altered metabolic pathways in the representative pathogens treated by Fraction 2 (p < 0.05), indicating multiple antibacterial modes. Overall, this study first demonstrates the antibacterial activity of the MPE from the fruit of A. villosum Lour., and should be useful for its application in the medicinal and food preservative industries against common pathogens.

Composition Analysis and Nutritional Value Evaluation of Amino Acids in the Fruit of 161 Jujube Cultivars

Amino acids are an essential group of compounds involved in protein synthesis and various metabolic and immune reactions in the human body. Chinese jujubes (Ziziphus jujuba Mill.) are an important fruit and medicinal plant which are native to China and have been introduced into around 50 countries. However, systematic research on the composition and content diversity of amino acids in the jujube is still lacking. In this experiment, the amino acid composition and the contents of the dominant amino acids in the fruit of 161 cultivars of jujube were determined by HPLC. Of the twenty-one kinds of amino acids detected, a total of fourteen kinds of amino acids were detected, of which eight kinds of amino acids were relatively high, including five essential amino acids (threonine, valine, isoleucine, leucine, and phenylalanine) and three nonessential amino acids (glycine, alanine, and proline). However, the contents of the remaining six amino acids were relatively low (aspartic acid, glutamic acid, histidine, serine, arginine, and tryptophan). Therefore, the eight primary amino acids were used as the index to evaluate the amino acids of 161 jujube varieties. Proline accounts for 56.8% of the total amino acid content among the eight amino acids. The total content of the eight primary amino acids in most jujube varieties was 1-1.5 g/100 g, and the highest content of 'Zaoqiangmalianzao' was 2.356 g/100 g. The average content of proline was 6.01-14.84 times that of the other seven amino acids. According to the WHO/FAO revised model spectrum of ideal essential amino acids for humans, 19 cultivars met the E/T (essential amino acids/total amino acids) standard, and their values ranged from 35% to 45%; 12 cultivars meet E/NE (non-essential amino acids) ≥ 60%. All cultivars reached the requirement of BC (branched-chain amino acids)/E ≥ 40% with 15 cultivars over 68%. One hundred and fifty-seven cultivars reach the standard of BC/A (aromatic amino acids) ≈ 3.0~3.5. The amino acid ratio coefficient analysis showed that phenylalanine was the first limiting amino acid of all the jujube cultivars. The SRC (the score of amino acid ratio coefficient) values of 134 cultivars were between 50% and 70%, with 12 cultivars over 70%, indicating that jujube fruits are of high nutritional value in terms of amino acids. Based on the principal component analysis and comprehensive ranking of amino acid nutritional value, the top five cultivars were screened from the 161 ones tested, i.e., 'Tengzhouchanghongzao', 'Xinzhengxiaoyuanzao', 'Hanguowudeng', 'Xuputiansuanzao', and 'Lichengxiaozao'. This study established, firstly, a complete basic data analysis of amino acid content in jujube fruit which could be used to select germplasm resources suitable for developing functional amino acid food, and provide theoretical support for the high value utilization of amino acids in jujubes.

Biomolecular glass with amino acid and peptide nanoarchitectonics

Glass is ubiquitous in life and widely used in various fields. However, there is an urgent need to develop biodegradable and biorecyclable glasses that have a minimal environmental footprint toward a sustainable society and a circular materials economy. Here, we report a family of eco-friendly glasses of biological origin fabricated using biologically derived amino acids or peptides through the classic heating-quenching procedure. Amino acids and peptides with chemical modification at their ends are found able to form a supercooled liquid before decomposition and eventually glass upon quenching. These developed glasses exhibit excellent glass-forming ability and optical characteristics and are amenable to three-dimensional-printed additive manufacturing and mold casting. Crucially, the glasses show biocompatibility, biodegradability, and biorecyclability beyond the currently used commercial glasses and plastic materials.

Ginsenoside Rg1 can reverse fatigue behavior in CFS rats by regulating EGFR and affecting Taurine and Mannose 6-phosphate metabolism

Background: Chronic fatigue syndrome (CFS) is characterized by significant and persistent fatigue. Ginseng is a traditional anti-fatigue Chinese medicine with a long history in Asia, as demonstrated by clinical and experimental studies. Ginsenoside Rg1 is mainly derived from ginseng, and its anti-fatigue metabolic mechanism has not been thoroughly explored. Methods: We performed non-targeted metabolomics of rat serum using LC-MS and multivariate data analysis to identify potential biomarkers and metabolic pathways. In addition, we implemented network pharmacological analysis to reveal the potential target of ginsenoside Rg1 in CFS rats. The expression levels of target proteins were measured by PCR and Western blotting. Results: Metabolomics analysis confirmed metabolic disorders in the serum of CFS rats. Ginsenoside Rg1 can regulate metabolic pathways to reverse metabolic biases in CFS rats. We found a total of 34 biomarkers, including key markers Taurine and Mannose 6-phosphate. AKT1, VEGFA and EGFR were identified as anti-fatigue targets of ginsenoside Rg1 using network pharmacological analysis. Finally, biological analysis showed that ginsenoside Rg1 was able to down-regulate the expression of EGFR. Conclusion: Our results suggest ginsenoside Rg1 has an anti-fatigue effect, impacting the metabolism of Taurine and Mannose 6-phosphate through EGFR regulation. This demonstrates ginsenoside Rg1 is a promising alternative treatment for patients presenting with chronic fatigue syndrome.

Effectiveness and safety of kamikihito, a traditional Japanese medicine, in managing anxiety among female patients with intractable chronic constipation

BACKGROUND AND PURPOSE

The prevalence of anxiety in patients with chronic constipation is particularly high and these individuals are not necessarily satisfied by normal treatments targeting the gastrointestinal tract. Kamikihito, a traditional Japanese Kampo medicine, has been widely used to date in treating anxiety and neurosis in Japan. We conducted a single-arm, open-label pilot study of female patients with intractable chronic constipation and anxiety who took kamikihito by mouth for 12 weeks.

MATERIALS AND METHODS

Validated symptom questionnaires on anxiety and gastrointestinal symptoms [the Profile of Mood States, second edition (POMS2); the State-Trait Anxiety Inventory (STAI); and the Gastrointestinal Symptom Rating Scale (GSRS)] were completed at each study visit. Plasma, salivary, and stool samples were also assessed to evaluate levels of clinical bioactive substances linked to stress and inflammation, oxidative levels, the metabolome profile, and gut microbiota.

RESULTS

Twenty-four patients completed this study. Anxiety was significantly reduced at four and 12 weeks (Tension-Anxiety subscale of the POMS2, p = 0.006 and p = 0.039; Trait anxiety score of the STAI, p < 0.001 and p = 0.034), while the total GSRS score was improved at 12 weeks (p = 0.039). Targeted metabolomics in plasma showed significant alterations in some metabolites associated with psychological symptoms, such as O-phosphoethanolamine. No significant differences were found between pre- and posttreatment levels of clinical bioactive substances related to stress and inflammation, oxidative levels, and the gut microbiota in this cohort. No serious adverse events occurred.

CONCLUSION

Kamikihito ameliorated psychological and gastrointestinal symptoms in patients with chronic constipation. In parallel with the onset of efficacy, kamikihito modulated some anxiety-related metabolites. Kamikihito was safe and well-tolerated.

An open-label, single-center pilot study to test the effects of an amino acid mixture in older patients admitted to internal medicine wards

OBJECTIVE

Older patients are frequently subjected to prolonged hospitalization and extended bed rest, with a negative effect on physical activity and caloric intake. This results in a consistent loss of muscle mass and function, which is associated with functional decline and high mortality. The aim of this study was to investigate the effect of 1 wk of oral amino acid (AA) supplementation in older patients subjected to low mobility during hospitalization.

METHODS

Hospitalized older patients (69-87) were included in the control group (n = 50) or were administered 25 g of AA mixture (n = 44) twice daily throughout 7 d of low mobility. We collected data related to length of stay as primary outcome measure. In-hospital mortality, 90-d postdischarge mortality, 90-d postdischarge rehospitalization, and falls also were considered. Moreover, variations of anthropometric measures, body composition and muscle architecture/strength, circulating interleukins, and oxidative stress markers between the beginning and the end of the supplementation period were analyzed as secondary outcomes.

RESULTS

Similar values were reported between the two groups regarding age (76.6 ± 6.8 versus 79 ± 7.2 y old), body weight (61.5 ± 14.3 versus 62.1 ± 16.1 kg), and body mass index (28.7 ± 4.15 versus 28.1 ± 3.62 kg/m2). Although no difference in terms of in-hospital, 90-d postdischarge, or overall mortality rate was observed between the two groups, a reduction in length of stay, 90-d postdischarge hospitalization, and falls was observed in the AA supplementation group rather than in controls. Furthermore, the AA mixture limited muscle architecture/strength impairment and circulating oxidative stress, which occurred during hospitalization-related bed rest. The latter data was associated with increased circulating levels of anti-inflammatory cytokines interleukin-4 and -10.

CONCLUSIONS

These results suggest that the AA mixture limits several alterations associated with low mobility in older hospitalized patients, such as length of stay, 90-d postdischarge hospitalization, and falls, preventing the loss of muscle function, as well as the increase of circulating interleukins and oxidative stress markers.

Dietary strategies for mitigating osteosarcopenia in older adults: a narrative review

The synchronic loss of bone mineral density and decrease in muscle mass, strength, and function defines the scenario of osteosarcopenia, which is associated with an increased risk of falls and fractures in older adults. An important role in preventing muscle and bone loss is played by nutritional factors, in particular the intake of proteins, calcium, magnesium and vitamin D. This review summarizes the available literature concerning the influence of protein intake and supplementation (vitamin D, Ca, Mg, branched-chain amino acids) on the decline of musculoskeletal integrity in healthy older adults. Furthermore, in this paper, we attempted to give some suggestions to build up adequate nutritional and dietary strategies against the age-related loss of muscle and bone mass.

Maternal HMB treatment affects bone and hyaline cartilage development in their weaned piglets via the leptin/osteoprotegerin system

It has been demonstrated in animal studies that prenatal administration of β-hydroxy-β-methylbutyrate (HMB, metabolite of leucine) influences general growth and mechanical endurance of long bones in newborn offspring in sex-dependent manner. The present experiment was conducted to evaluate the effect of HMB treatment of pregnant sows on bone development in offspring at weaning. From 70th day until the 90th day of gestation, sows received either a basal diet (n = 12) or the same diet supplemented with HMB (n = 12) at the dose of 0.2 g/kg of body weight/day. Femora obtained from six males and females in each group weaned at the age of 35 days were examined. Maternal HMB treatment significantly enhanced body weight and changed bone morphology increasing femur mechanical strength in both sexes. Maternal HMB supplementation also elevated bone micro- and macroelement concentrations and enhanced content of proteoglycans in articular cartilage. Based on the obtained results, it can be concluded that maternal HMB supplementation in the mid-gestation period significantly accelerated bone development in both sexes by upregulation of a multifactorial system including leptin and osteoprotegerin. However, the sex (irrespective of the HMB treatment) was the factor which influenced the collagen structure in cartilages and trabecular bone, as demonstrated both by the Picrosirius red staining and performed analysis of thermal stability of collagenous tissues. The structural differences in collagen between males and females were presumably related to a different collagen maturity. No studies conducted so far provided a detailed morphological analysis of bone, articular cartilage, growth plate and the activities of the somatotropic and pituitary-gonadal axes, as well as leptin/osteoprotegerin system in weaned offspring prenatally treated with HMB. This study showed also the relationship between the maternal HMB treatment and bone osteometric and mechanical traits, hormones, and growth and bone turnover markers such as leptin, osteoprotegerin and insulin-like growth factor-1.

On the effects of tyrosine supplementation on interference control in a randomized, double-blind placebo-control trial

Exerting cognitive control is an effortful endeavor that is strongly modulated by the availability of dopamine (DA) and norepinephrine (NE), which are both synthesized from the amino acid precursor tyrosine. Supplementing tyrosine may increase the synthesis of both catecholamines. This has been suggested to improve executive functioning and potentially even counteract depletion effects in this domain. Yet, it has remained unclear whether tyrosine also improves interference control and whether subliminally and consciously triggered response conflicts are subject to the same modulation. We investigated this question in a double-blind intra-individual study design. N = 26 young healthy subjects performed two consecutive cognitive control tasks that triggered automatic incorrect response tendencies; once with tyrosine supplementation and once with a placebo. The results show that tyrosine decreased the size of consciously perceived conflicts in a Simon Task, but not a Flanker task, thus suggesting that stimulus-response conflicts might be modulated differently from stimulus-stimulus conflicts. At the same time, tyrosine supplementation increased the size of subliminally triggered conflicts whenever a different, consciously perceived conflict was also present. This suggests that control-related DA and NE release may increase visuo-motor priming, especially when no conflict-specific top-down control may be triggered to counteract subliminal priming effects. Also, these subliminal conflicts might be aggravated by concurrent control investments in other kinds of conflict. Taken together, our data suggest that beneficial effects of tyrosine supplementation do not require depletion effects, but may be limited to situations where we consciously perceive a conflict and the associated need for conflict-specific control.

L-tyrosine supplementation does not ameliorate skeletal muscle dysfunction in zebrafish and mouse models of dominant skeletal muscle α-actin nemaline myopathy

L-tyrosine supplementation may provide benefit to nemaline myopathy (NM) patients, however previous studies are inconclusive, with no elevation of L-tyrosine levels in blood or tissue reported. We evaluated the ability of L-tyrosine treatments to improve skeletal muscle function in all three published animal models of NM caused by dominant skeletal muscle α-actin (ACTA1) mutations. Highest safe L-tyrosine concentrations were determined for dosing water and feed of wildtype zebrafish and mice respectively. NM TgACTA1^D286G-eGFP zebrafish treated with 10 μM L-tyrosine from 24 hours to 6 days post fertilization displayed no improvement in swimming distance. NM TgACTA1^D286G mice consuming 2% L-tyrosine supplemented feed from preconception had significant elevations in free L-tyrosine levels in sera (57%) and quadriceps muscle (45%) when examined at 6–7 weeks old. However indicators of skeletal muscle integrity (voluntary exercise, bodyweight, rotarod performance) were not improved. Additionally no benefit on the mechanical properties, energy metabolism, or atrophy of skeletal muscles of 6–7 month old TgACTA1^D286G and KIActa1^H40Y mice eventuated from consuming a 2% L-tyrosine supplemented diet for 4 weeks. Therefore this study yields important information on aspects of the clinical utility of L-tyrosine for ACTA1 NM.

Synergistic effects of citrulline supplementation and exercise on performance in male rats: evidence for implication of protein and energy metabolisms

Background: Exercise and citrulline (CIT) are both regulators of muscle protein metabolism. However, the combination of both has been under-studied yet may have synergistic effects on muscle metabolism and performance. Methods: Three-month-old healthy male rats were randomly assigned to be fed ad libitum for 4 weeks with either a citrulline-enriched diet (1 g·kg^-1·day^-1) (CIT) or an isonitrogenous standard diet (by addition of nonessential amino acid) (Ctrl) and trained (running on treadmill 5 days·week^-1) (ex) or not. Maximal endurance activity and body composition were assessed, and muscle protein metabolism (protein synthesis, proteomic approach) and energy metabolism [energy expenditure, mitochondrial metabolism] were explored. Results: Body composition was affected by exercise but not by CIT supplementation. Endurance training was associated with a higher maximal endurance capacity than sedentary groups (P<0.001), and running time was 14% higher in the CITex group than the Ctrlex group (139±4 min versus 122±6 min, P<0.05). Both endurance training and CIT supplementation alone increased muscle protein synthesis (by +27% and +33%, respectively, versus Ctrl, P<0.05) with an additive effect (+48% versus Ctrl, P<0.05). Mitochondrial metabolism was modulated by exercise but not directly by CIT supplementation. However, the proteomic approach demonstrated that CIT supplementation was able to affect energy metabolism, probably due to activation of pathways generating acetyl-CoA. Conclusion: CIT supplementation and endurance training in healthy male rats modulates both muscle protein and energy metabolisms, with synergic effects on an array of parameters, including performance and protein synthesis.

Guanidinoacetic acid versus creatine for improved brain and muscle creatine levels: a superiority pilot trial in healthy men

In this randomized, double-blind, crossover trial, we evaluated whether 4-week supplementation with guanidinoacetic acid (GAA) is superior to creatine in facilitating creatine levels in healthy men (n = 5). GAA (3.0 g/day) resulted in a more powerful rise (up to 16.2%) in tissue creatine levels in vastus medialis muscle, middle-cerebellar peduncle, and paracentral grey matter, as compared with creatine (P < 0.05). These results indicate that GAA as a preferred alternative to creatine for improved bioenergetics in energy-demanding tissues.

Taurine drinking ameliorates hepatic granuloma and fibrosis in mice infected with Schistosoma japonicum

In schistosomiasis, egg-induced hepatic granuloma formation is a cytokine-mediated, predominantly CD4⁺ Th2 immune response that can give rise to hepatic fibrosis. Hepatic fibrosis is the main cause of increased morbidity and mortality in humans with schistosome infection. Taurine has various physiological functions and hepatoprotective properties as well as anti-inflammatory and immunomodulatory activity. However, little is known about the role of taurine in schistosome egg-induced granuloma formation and fibrosis. We aimed to evaluate the therapeutic potential of taurine as preventative treatment for Schistosoma japonicum infection. Mice infected with S. japonicum cercariae were supplied with taurine drinking water (1% w/v) for 4 weeks starting at 4 weeks post-infection. Taurine supplementation significantly improved the liver pathologic findings, reduced the serum levels of aminotransferases and area of hepatic granuloma, and prevented fibrosis progression. In addition, taurine decreased the expression of the granulomatous and fibrogenic mediators transforming growth factor β1, tumor necrosis factor α, monocyte chemotactic protein 1α and macrophage inflammatory protein 1α as well as the endoplasmic reticulum stress marker glucose-regulated protein 78. Thus, taurine can significantly attenuate S. japonicum egg-induced hepatic granuloma and fibrosis, which may depend in part on the downregulation of some relevant cytokine/chemokines and reducing the endoplasmic reticulum stress response.

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Taurine has potential as preventative & therapeutic treatment for schistosomiasis.

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Taurine reduced the development of liver pathology caused by S. japonicum infection.

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Taurine attenuated S. japonicum egg-induced hepatic granuloma and fibrosis.