Is taurine a functional nutrient?

First Insights into the Urinary Metabolome of Captive Giraffes by Proton Nuclear Magnetic Resonance Spectroscopy

The urine from 35 giraffes was studied by untargeted ¹H-NMR, with the purpose of obtaining, for the first time, a fingerprint of its metabolome. The metabolome, as downstream of the transcriptome and proteome, has been considered as the most representative approach to monitor the relationships between animal physiological features and environment. Thirty-nine molecules were unambiguously quantified, able to give information about diet, proteins digestion, energy generation, and gut-microbial co-metabolism. The samples collected allowed study of the effects of age and sex on the giraffe urinary metabolome. In addition, preliminary information about how sampling procedure and pregnancy could affect a giraffe’s urinary metabolome was obtained. Such work could trigger the setting up of methods to non-invasively study the health status of giraffes, which is utterly needed, considering that anesthetic-related complications make their immobilization a very risky practice.

Hypotaurine promotes longevity and stress tolerance via the stress response factors DAF-16/FOXO and SKN-1/NRF2 in Caenorhabditis elegans

Hypotaurine, an important sulfur-containing and nonpeptidic amino acid, is a precursor of taurine and an antioxidant.

The effects of taurine supplementation on oxidative stress indices and inflammation biomarkers in patients with type 2 diabetes: a randomized, double-blind, placebo-controlled trial

BACKGROUND

Reduced serum level of taurine in type 2 diabetes mellitus (T2DM) was shown to be associated with the metabolic alterations and clinical complications of diabetes. Dietary supplementation with taurine may attenuate oxidative stress and inflammatory responses in T2DM as well as alleviate diabetes-induced complications. Hence, this study evaluated the effect of taurine supplementation on oxidative stress and inflammatory biomarkers in patients with T2DM.

METHODS

Fifty patients with T2DM were randomly allocated to two groups to consume either taurine (containing 1000 mg taurine), or placebo (containing crystalline microcellulose) three times per day for 8 weeks. Anthropometric data, dietary intake, serum total antioxidant capacity (TAC), malondialdehyde (MDA), the activities of antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT), serum levels of tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and high-sensitivity C-reactive protein (hs-CRP) were assessed before and after intervention.

RESULTS

There was a significant increase in SOD (5.1%, p = 0.004) and CAT (4.22%, p = 0.001) after 8 weeks of taurine supplementation. In addition, serum levels of MDA (26.33%, p = 0.001), hs-CRP (16.01%, p = 0.001), and TNF-α (11.65%, p = 0.03) significantly decreased in the taurine group compared with baseline. Following treatment, the taurine group had fewer serum levels of MDA (p = 0.04), hs-CRP (p = 0.002) and TNF-α (p = 0.006) than the placebo group. Also, a significant increase was observed in SOD (p = 0.007), and CAT (p = 0.001) in the taurine group compared with the placebo group. There were no differences in the serum levels of IL-6 or TAC.

CONCLUSIONS

The findings of this study showed that taurine supplementation improved some oxidative stress indices and inflammatory biomarkers in patients with T2DM.Trial registration The protocol of this clinical trial is registered with the Iranian Registry of Clinical Trials (http://www.IRCT.IR, identifier: IRCT20121028011288N16).

Therapeutic role of taurine as antioxidant in reducing hypertension risks in rats

AIM

The current investigation focused on the therapeutic role of the administration of taurine on hypertensive rats to reduce or cure the hazard effects of hypertension problems.

METHODOLOGY

This research included 2 experiments; 1st was done to survey the variations that might occur in blood pressure (BP) of male rats because of the fed 8% NaCl diet for 4 weeks. 2nd experiment, it contains normal control rats', hypertensive rats were served as hypertension recovery group and hypertensive rats were took orally by the help of gastric tube 50 mg taurine/100 g b.wt/day for four weeks and served as taurine group.

RESULTS

1st experimental, clarified a significant elevation in BP, body weight, serum cholesterol, triglycerides, LDL, activities of serum cardiac enzymes, endothelin-1, ADMA, MDA and TNF-α in hypertensive rats' group. On contrary, there is a significant reduction in serum level of TNO and antioxidant enzymes level in relation to the control group. A numerical variation but not statistically significant was happened in HDL in hypertensive rats' group as compared to their matching results in control rats' group. 2nd experimental taurine significantly reduced the BP as compared with hypertensive control. Furthermore, a significant improvement occurred in the mean value of most investigation parameters in hypertensive animal group which treated with taurine.

CONCLUSION

The previous data could be concluded that, there is an obvious amelioration effects of taurine on hypertensive rats by reducing the hazard effects of hypertension problems. The primary mechanisms were discussed according to existing published investigations.

Safety and efficacy of taurine as an add-on treatment for tics in youngsters

BACKGROUND AND PURPOSE

The pathophysiological model of tics generally describes disruption of γ-aminobutyric acid transmission, and taurine is found to be an agonist of γ-aminobutyric acid receptors. The study aimed to evaluate the safety and efficacy of taurine as an add-on treatment for tics.

METHODS

Four hundred and four youngsters with tic disorders were randomly assigned to 12 weeks of either oral taurine or placebo. The Yale Global Tic Severity Scale was used to measure tic severity. The primary outcome measure was global severity scores reduced by more than 60% compared with baseline scores.

RESULTS

Three hundred and eighty-two patients were successfully treated. At week 4, no significant differences were found in the treatment effect and the total occurrence of adverse drug reactions between the taurine and placebo groups. At week 12, the proportion of significant improvement in tics was significantly higher in the taurine group than the placebo group (53.4% with taurine versus 34.5% without taurine; relative risk 1.546; P < 0.001), and no group differences were found in the total occurrence of adverse drug reactions.

CONCLUSIONS

Taurine is safe and effective for tics.

Urinary Taurine Excretion and Risk of Late Graft Failure in Renal Transplant Recipients

Taurine is a sulfur containing nutrient that has been shown to protect against oxidative stress, which has been implicated in the pathophysiology leading to late graft failure after renal transplantation. We prospectively investigated whether high urinary taurine excretion, reflecting high taurine intake, is associated with low risk for development of late graft failure in renal transplant recipients (RTR). Urinary taurine excretion was measured in a longitudinal cohort of 678 stable RTR. Prospective associations were assessed using Cox regression analyses. Graft failure was defined as the start of dialysis or re-transplantation. In RTR (58% male, 53 ± 13 years old, estimated glomerular filtration rate (eGFR) 45 ± 19 mL/min/1.73 m²), urinary taurine excretion (533 (210–946) µmol/24 h) was significantly associated with serum free sulfhydryl groups (β = 0.126; P = 0.001). During median follow-up for 5.3 (4.5–6.0) years, 83 (12%) patients developed graft failure. In Cox regression analyses, urinary taurine excretion was inversely associated with graft failure (hazard ratio: 0.74 (0.67–0.82); P < 0.001). This association remained significant independent of potential confounders. High urinary taurine excretion is associated with low risk of late graft failure in RTR. Therefore, increasing taurine intake may potentially support graft survival in RTR. Further studies are warranted to determine the underlying mechanisms and the potential of taurine supplementation.

Metabolic and chemical regulation of tRNA modification associated with taurine deficiency and human disease

Modified uridine containing taurine, 5-taurinomethyluridine (τm5U), is found at the anticodon first position of mitochondrial (mt-)transfer RNAs (tRNAs). Previously, we reported that τm5U is absent in mt-tRNAs with pathogenic mutations associated with mitochondrial diseases. However, biogenesis and physiological role of τm5U remained elusive. Here, we elucidated τm5U biogenesis by confirming that 5,10-methylene-tetrahydrofolate and taurine are metabolic substrates for τm5U formation catalyzed by MTO1 and GTPBP3. GTPBP3-knockout cells exhibited respiratory defects and reduced mitochondrial translation. Very little τm5U34 was detected in patient's cells with the GTPBP3 mutation, demonstrating that lack of τm5U results in pathological consequences. Taurine starvation resulted in downregulation of τm5U frequency in cultured cells and animal tissues (cat liver and flatfish). Strikingly, 5-carboxymethylaminomethyluridine (cmnm5U), in which the taurine moiety of τm5U is replaced with glycine, was detected in mt-tRNAs from taurine-depleted cells. These results indicate that tRNA modifications are dynamically regulated via sensing of intracellular metabolites under physiological condition.

Bone microstructure of mice after prolonged taurine treatment

Taurine, a sulphur - containing amino acid, has been termed a functional nutrient. Its synthetic form is a common ingredient in supplements and energy drinks. There is no information concerning taurine impact on bone microstructure after prolonged supplemental use. Also, differences in bone parameters of mice following taurine exposure are unknown. In this study, a detailed microstructure of compact and trabecular bone tissues of mice subchronically exposed to taurine was determined. Animals (n=12) were segregated into three groups: E1 group - mice received 20 mg/kg b.w. of taurine per day during 8 weeks; E2 group - mice were fed by taurine at a dose of 40 mg/kg b.w. for 8 weeks and a control (C) group. Decreased density of secondary osteons, increased sizes of primary osteon's vascular canals (P<0.05) were observed in taurine - treated animals. Cortical bone thickness, trabecular thickness were decreased (P<0.05) in E1 group, and relative volume of trabecular bone was lower (P<0.05) in E2 group as compared to C group. According to our results, prolonged taurine exposure at the doses used in this study can negatively affect both compact and trabecular bone tissues microstructure.

Integration of Metabolomics and Lipidomics Reveals Metabolic Mechanisms of Triclosan-Induced Toxicity in Human Hepatocytes

Triclosan (TCS), an extensively used antimicrobial agent, has raised considerable concern due to its hepatocarcinogenic potential. However, previous hepatotoxicity studies primarily focused on the activation of specific intracellular receptors, the underlying mechanisms still warrant further investigation at the metabolic level. Herein, we applied metabolomics in combination with lipidomics to unveil TCS-related metabolic responses in human normal and cancerous hepatocytes. Endogenous and exogenous metabolites were analyzed for the identification of metabolic biomarkers and biotransformation products. In L02 normal cells, TCS exposure induced the up-regulation of purine metabolism and amino acid metabolism, caused lipid accumulation, and disturbed energy metabolism. These metabolic disorders in turn enhanced the overproduction of reactive oxygen species (ROS), leading to the alteration of antioxidant enzyme activities, down-regulation of endogenous antioxidants, and peroxidation of lipids. TCS-induced oxidative stress is thus considered to be one crucial factor for hepatotoxicity. However, in HepG2 cancer cells, TCS underwent fast detoxification through phase II metabolism, accompanied by the enhancement of energy metabolism and elevation of antioxidant defense system, which contributed to the potential effects of TCS on human hepatocellular carcinoma development. These different responses of metabolism between normal and cancerous hepatocytes provide novel and robust perspectives for revealing the mechanisms of TCS-triggered hepatotoxicity.

Taurine enhances mouse cochlear neural stem cell transplantation via the cochlear lateral wall for replacement of degenerated spiral ganglion neurons via sonic hedgehog signaling pathway

The aim of this paper is to investigate the potential beneficial effects of taurine in cochlear neural stem cell (NSC) transplantation and elucidate the underlying molecular mechanism. The NSC cells were isolated from neonatal Balb/c mice and an auditory neuropathy gerbil model was established by microinjection of ouabain. The spiral ganglion neurons (SGN) were characterized with immunofluorescence stained with Tuj1 antibody. Cell proliferation was determined by BrdU incorporation assay and the morphologic index was measured under the light microscope. The relative protein level was determined by immunoblotting. The hearing of the animal model was scored by click- and tone burst-evoked auditory brainstem response (ABR). Here we consolidated our previous finding that taurine stimulated SGN density and the proliferation index, which were completely abolished by Shh inhibitor, cyclopamine. Transplantation of cochlear NSCs combined with taurine significantly improved ouabain-induced auditory neuropathy in gerbils. In addition, cyclopamine antagonized taurine's effect on glutamatergic and GABAergic neuron population via suppression of VGLUT1 and GAT1 expression. Mechanistically, taurine evidently activated the Sonic HedgeHog pathway and upregulated Shh, Ptc-1, Smo and Gli-1 proteins, which were specifically blockaded by cyclopamine. Here, for the first time demonstrated we that co-administration with taurine significantly improved NSC transplantation and the Shh pathway was identified in this beneficial effect.

Creating a New Pathway in Corynebacterium glutamicum for the Production of Taurine as a Food Additive

Taurine is a biologically and physiologically valuable food additive. However, commercial taurine production mainly relies on environmentally harmful chemical synthesis. Herein, for the first time in bacteria, we attempted to produce taurine in metabolically engineered Corynebacterium glutamicum. The taurine-producing strain was developed by introducing cs, cdo1, and csad genes. Interestingly, while the control strain could not produce taurine, the engineered strains successfully produced taurine via the newly introduced metabolic pathway. Furthermore, we investigated the effect of a deletion strain of the transcriptional repressor McbR gene on taurine production. As a result, sulfur accumulation and l-cysteine biosynthesis were reinforced by the McbR deletion strain, which further increased the taurine production by 2.3-fold. Taurine production of the final engineered strain Tau11 was higher than in other previously reported strains. This study demonstrated a potential approach for eco-friendly biosynthesis as an alternative to the chemical synthesis of a food additive.

Long term treatment of metformin impedes development of chemoresistance by regulating cancer stem cell differentiation through taurine generation in ovarian cancer cells

Development of resistance poses a significant challenge to effective first-line platinum based therapy for epithelial ovarian cancer patients. Cancer Stem Cells are envisaged as a critical underlying factor for therapy resistance. Thus, there is a critical need for developing approaches to diminish the enrichment of cancer stem cells and acquirement of resistance. Administration of metformin, a commonly prescribed drug against Type II diabetes exhibited promising effect in the management of ovarian cancer. However, the effect of long term administration of low dose of metformin as an adjuvant to cisplatin and paclitaxel during acquirement of chemoresistant phenotype has not been investigated so far. Using two isogenic cellular chemoresistant models (A2780 and OAW42) developed in the presence or absence of metformin, we demonstrated the ability of metformin to impede the development of resistance through increased drug sensitivity, increased proliferation, and reduced migratory abilities of the resistant cells. Metformin introduction also decreased the cancer stem cell population, expression of specific biomarkers and pluripotent genes. Further metabolic profiling of these cells using ¹H-Nuclear Magnetic Resonance spectroscopy revealed significant modulation in taurine and histidine levels in resistant cells developed in the presence of metformin. Intriguingly, taurine treatment considerably reduced the cancer stem cell population and chemoresistance in resistant cells, indicating a novel role of taurine in differentiation of ovarian cancer stem cells. Altogether this is the first report on the potential role of metformin for targeting the cancer stem cell population via up regulation of taurine, leading to impediment in the acquirement of chemoresistance.

Prolonging healthy aging: Longevity vitamins and proteins

It is proposed that proteins/enzymes be classified into two classes according to their essentiality for immediate survival/reproduction and their function in long-term health: that is, survival proteins versus longevity proteins. As proposed by the triage theory, a modest deficiency of one of the nutrients/cofactors triggers a built-in rationing mechanism that favors the proteins needed for immediate survival and reproduction (survival proteins) while sacrificing those needed to protect against future damage (longevity proteins). Impairment of the function of longevity proteins results in an insidious acceleration of the risk of diseases associated with aging. I also propose that nutrients required for the function of longevity proteins constitute a class of vitamins that are here named "longevity vitamins." I suggest that many such nutrients play a dual role for both survival and longevity. The evidence for classifying taurine as a conditional vitamin, and the following 10 compounds as putative longevity vitamins, is reviewed: the fungal antioxidant ergothioneine; the bacterial metabolites pyrroloquinoline quinone (PQQ) and queuine; and the plant antioxidant carotenoids lutein, zeaxanthin, lycopene, α- and β-carotene, β-cryptoxanthin, and the marine carotenoid astaxanthin. Because nutrient deficiencies are highly prevalent in the United States (and elsewhere), appropriate supplementation and/or an improved diet could reduce much of the consequent risk of chronic disease and premature aging.

Liver Antioxidant Enzyme Activities Increase After Taurine in Ovariectomized Rats

The present study was performed to know the effects of taurine on the lipid level of plasma and liver, lipid peroxidation and antioxidative enzyme activities of liver tissue in ovariectomized (OVX) rats fed cholesterol. Twenty-four female SD rats (200 ± 5 g) were grouped; sham and ovariectomy groups, which were each randomly subgrouped; fed control and control supplemented with taurine (20 g/kg diet). The serum total cholesterol, TG (triglyceride), LDL-cholesterol, athrogenic index, and HDL-cholesterol of taurine diet group were not statistically different. Also the levels of liver total cholesterol, triglyceride were not considerably different in different diets. The lipid peroxidation of malondialdehyde concentration was considerably lower in taurine-feeding group than control-feeding group in ovariectomy group. The superoxide dismutase activity in liver tissue was significantly higher in rats fed taurine than in rats fed control diet in OVX rats. GSH-Px (glutathione peroxidase) activity was statistically greater at the rats fed taurine diets compared to rats fed control diet in ovariectomy group. Activity of catalase was higher in taurine group than in control group in ovariectomy group, but it was not significantly different. In conclusion, taurine supplementation was beneficial on antioxidative enzyme activities of liver tissue in ovariectomized rats fed cholesterol.

Taurine Alleviate Hexabromocyclododecane-Induced Cytotoxicity in PC12 Cells via Inhibiting Oxidative Stress

Hexabromocyclododecane (HBCD) is a widely used brominated flame retardant. Its adverse effects on brain had been observed. Taurine, a sulfur amino acid, take part in many brain physiological functions and exhibits protective effects on a variety of detrimental situations. In this paper, we explored the protections of taurine on cytotoxicity induced by HBCD in PC12 cells. PC12 cells were pretreated with taurine (1 mM, 3 mM and 9 mM) for 30 min before 10 μM HBCD treatment for 24 h. Then, the cell survival was assayed by the lactate dehydrogenase (LDH) release and trypan blue dyeing method. The formation of reactive oxygen species (ROS) and a collapse of mitochondrial membrane potential (MMP) were evaluated with a fluorescence microplate reader using the non-fluorescent probe 2'7'-dichlorofluorescin diacetate (DCFH-DA) and the fluorescent cationic dyestuff Rhodamine 123 (Rh 123), respectively. Further, the activity of many antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and the content of glutathione (GSH) were tested by kits. Our results displayed that taurine significantly decreased the cell death induced by HBCD, prevented ROS production and disruption of mitochondrial membrane potential, and reversed the decline of SOD, CAT, GPx activity and GSH content induced by HBCD. These results suggested that taurine could alleviate cytotoxicity induced by HBCD in PC12 cells through inhibition of oxidative stress.

Protection of Taurine Against Arsenic-Induced DNA Damage of Mice Kidneys

The purpose of this study was to explore the protective capacity of taurine on arsenic (As)-induced neurotoxicity. Thirty mice were used and ten rats in each group. We treated the As exposure group with 4 ppm As2O3 for 60 days by drinking water and the protective group with 4 ppm As2O3 and 150 mg/kg taurine. Drinking water was only given in the control group. Pathologic changes and DNA damage in the mice kidney were examined by HE staining, immunohistochemistry and comet assay. Abnormal morphological changes were found in the kidney of As exposed mouse. Moreover, 8-hydroxy-2-deoxyguanosine (8-OHdG) expression and comet number, tail moment, and tail length of comet were markedly elevated in the As intoxication mice. However, histopathological changes and low expression of 8-OHdG were shown in the protective group. Our results indicate that supplementation of taurine protects against the histopathologic changes and DNA damage of mouse kidneys in As exposure group.

Randomised clinical trial: oral taurine supplementation versus placebo reduces muscle cramps in patients with chronic liver disease

BACKGROUND

Painful muscle cramps occur in the majority of patients with cirrhosis impacting significantly on quality of life and sleep patterns. They are frequently unrecognised or overlooked. Current management is based on anecdotal evidence or case study reports.

AIM

To investigate the effect of oral taurine supplementation on frequency, duration, and intensity of muscle cramps in patients with chronic liver disease.

METHODS

Patients with chronic liver disease who experienced three or more muscle cramps/week were enrolled in a double-blinded, randomised control, crossover, taurine dose-variable study. Each participant received either taurine supplementation or placebo for 4 weeks then crossed to the alternative arm. Primary outcome data for frequency, duration, and intensity of muscle cramps was recorded by participants. Participants recorded frequency, duration, and location of muscle cramps. Biochemical parameters, including serum taurine and methionine levels, were measured at each time point. Linear mixed models were used to analyse outcomes.

RESULTS

Forty-nine patients were enrolled in the study and 30 patients completed the protocol. Participants who were unable to complete the protocol were not included in the final analysis due to the absence of outcome data. The mean age of participants was 54.7 years and 70% were males. Oral taurine supplementation increased serum taurine levels (P < 0.001). There were no adverse side effects associated with taurine supplementation. Participants receiving 2 g taurine/d experienced a reduction in cramp frequency (seven cramps fewer/fortnight, P = 0.03), duration (89 minutes less/fortnight P = 0.03), and severity (1.4 units less on a Likert scale P < 0.004) compared to placebo.

CONCLUSIONS

Oral supplementation with 2 g taurine/d results in a clinically significant reduction in the frequency, duration, and intensity of muscle cramps in patients with chronic liver disease. Taurine should be considered as a safe and effective intervention in the management of muscle cramps in individuals with chronic liver disease. This study was registered with the Australian New Zealand Clinical Trials Register: ACTRN12612000289819.

Taurine enhances mouse cochlear neural stem cells proliferation and differentiation to sprial gangli through activating sonic hedgehog signaling pathway

To investigate the molecular mechanism underlying taurine-stimulated proliferation and differentiation of cochlear neural stem cells (NSCs) and potential involvement of Sonic Hedgehog (Shh) pathway. The NSCs were characterized with immunofluorescence stained with nestin antibody. Cell viability was determined by MTT assay. The relative proliferation was measured by BrdU incorporation assay. The morphologic index was measured under light microscope. The relative protein level was determined by immunoblotting. Here we presented our findings that taurine stimulated proliferation and neurite outgrowth of NSCs, which was completely abolished by Shh inhibitor cyclopamine. In addition, cyclopamine antagonized taurine's effect on glutamatergic and GABAergic neuron population via suppressing expressions of Ptc-1, Smo and Gli-1. Our data supported the critical role of Shh pathway underlying the protective effect of taurine on auditory neural system.

Genome-wide association studies identified variants for taurine concentration in Japanese Black beef

We performed genome-wide association studies (GWAS) using the BovineSNP50 array to detect significant single nucleotide polymorphisms (SNPs) that may affect the concentration of 22 free amino acids and three peptides in Japanese Black beef cattle. A total of 574 Japanese Black cattle and 40,657 SNPs from the array were used for this study. Genome-wide significant SNPs were detected for β-alanine (three SNPs on chromosomes 22 and 29) and taurine (26 SNPs on chromosome 22). Importantly, the top two SNPs for taurine were highly significant (p = 6.2 × 10^-21 ), and the frequency of the increase-concentration allele (Q) for taurine was found to be 0.73. The Q allele frequency of this population was similar to that of the other unrelated Japanese Black cattle, but different from that of the other breeds. In addition, the significant SNPs were not associated with carcass traits or fatty acid compositions. Interestingly, the top three of the four most significant SNPs for taurine were located near solute carrier family 6, member 6 (SLC6A6), which is a membrane transporter for taurine. We also found two associated variants in the 5'-upstream region of SLC6A6; however, they were less significantly associated than the SNPs from the BovineSNP50 array.

Effects and Mechanisms of Taurine as a Therapeutic Agent

Taurine is an abundant, β-amino acid with diverse cytoprotective activity. In some species, taurine is an essential nutrient but in man it is considered a semi-essential nutrient, although cells lacking taurine show major pathology. These findings have spurred interest in the potential use of taurine as a therapeutic agent. The discovery that taurine is an effective therapy against congestive heart failure led to the study of taurine as a therapeutic agent against other disease conditions. Today, taurine has been approved for the treatment of congestive heart failure in Japan and shows promise in the treatment of several other diseases. The present review summarizes studies supporting a role of taurine in the treatment of diseases of muscle, the central nervous system, and the cardiovascular system. In addition, taurine is extremely effective in the treatment of the mitochondrial disease, mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS), and offers a new approach for the treatment of metabolic diseases, such as diabetes, and inflammatory diseases, such as arthritis. The review also addresses the functions of taurine (regulation of antioxidation, energy metabolism, gene expression, ER stress, neuromodulation, quality control and calcium homeostasis) underlying these therapeutic actions.

Rice bran nutraceutics: A comprehensive review

Agro-industry yields ample quantity of several byproducts with considerable importance. These byproducts are mostly under-utilized, often used as animal feed or rejected as waste; hence their true potential is not harnessed. The use of such superfluous resources is of not only economic significance but also a form of commercial recycling. Rice bran is an important byproduct of rice milling industry with a global potential of 29.3 million tons annually. It is gaining great attention of the researchers due to its nutrient-rich composition, easy availability, low cost, high antioxidant potential, and promising effects against several metabolic ailments. Bioactive components of rice bran, mainly γ-oryzanol, have been reported to possess antioxidant, anti-inflammatory, hypocholesterolemic, anti-diabetic, and anti-cancer activities. Rice bran oil contains appreciable quantities of bioactive components and has attained the status of "Heart oil" due to its cardiac-friendly chemical profile. Nutraceutics have successfully been extracted from rice bran using several extraction techniques such as solvent extraction, supercritical fluid extraction, microwave-, and ultrasonic-assisted extraction. Current paper is an attempt to highlight bioactive moieties of rice bran along with their extraction technologies and health benefits.

Effect of taurine on immune function in mice with T-cell lymphoma during chemotherapy

OBJECTIVE

To observe the effect of taurine on immune function in mice with T-cell lymphoma during chemotherapy.

METHODS

A total of 40 C57BL/6 mice were selected and randomly divided into 4 groups, namely model group, chemotherapy group, taurine group and chemotherapy + taurine group, each containing 10 mice. Hypodermic injection was adopted to inoculate EL-4 cells in order to establish model of T-cell lymphoma. When the tumor achieved the size of 1 cm³, intervention treatments were given to the groups respectively. Mice in model group received 0.2 mL of normal saline which was intraperitoneally injected on Days 1, 8 and 15 with 3 weeks as a cycle; mice in chemotherapy group were administered with 80 mg/kg body weight of gemcitabine which was also intraperitoneally injected on Days 1, 8 and 15 with 3 weeks as a cycle; mice in taurine group were administered with 80 mg/kg body weight of taurine intraperitoneally injected daily for consecutive 8 d; mice in chemotherapy + taurine group were treated in the same manner as the mice in taurine group and chemotherapy group. Five mice were sacrificed at 2 and 3 weeks after intervention respectively, and the tumor tissues were collected and weighted after removal of auxiliary tissue, then the tumor inhibition rate was calculated. The thymus and spleen of mice sacrificed at 3 weeks after intervention were collected and weighted, and thymus and spleen indexes were calculated. Enzyme linked immunosorbent assay was used to detect the serum levels of IL-4, IL-10, IL-12 and IFN-γ in mice of each group.

RESULTS

The tumor weights in chemotherapy group, taurine group and chemotherapy + taurine group after 2 and 3 weeks of treatment were significantly lower than that in model group (P < 0.05); the tumor weight in chemotherapy + taurine group after 2 and 3 weeks of treatment was significantly lower than that in chemotherapy group (P < 0.05); the tumor inhibition rate in chemotherapy + taurine group was significantly higher than that in chemotherapy group and taurine group (P < 0.05); the thymus and spleen indexes in taurine group and chemotherapy + taurine group were significantly higher than those in chemotherapy group and model group (P < 0.05); the thymus and spleen indexes in chemotherapy group were significantly lower than those in model group (P < 0.05); after 3 weeks of treatment, the serum levels of IL-4, IL-12 and IFN-γ in chemotherapy group, taurine group and chemotherapy + taurine group were significantly lower than those in model group (P < 0.05); the IL-4 level in taurine group and chemotherapy + taurine group was significantly lower than that in chemotherapy group (P < 0.05); the serum level of IL-10 in chemotherapy group and chemotherapy + taurine group was significantly higher than that in model group and taurine group (P < 0.05); the serum level of IFN-γ in taurine group and chemotherapy + taurine group was significantly lower than that in model group and chemotherapy group (P < 0.05); after treatment of 3 weeks, the serum levels of IL-4 and IL-10 in chemotherapy group, taurine group and chemotherapy + taurine group were significantly lower than those in model group (P < 0.05), and IL-12 level was significantly higher than that in model group (P < 0.05); the level of IFN-γ in taurine group and chemotherapy + taurine group was significantly higher than that in model group (P < 0.05), while the level of IFN-γ in chemotherapy group was significantly lower than that in the other 3 groups (P < 0.05).

CONCLUSIONS

Taurine can effectively enhance the immune function of mice with T-cell lymphoma during chemotherapy, reduce the toxicity of chemotherapy.

Molecular mechanisms of nickel induced neurotoxicity and chemoprevention

Nickel (Ni) is widely used in many industrial sectors such as alloy, welding, printing inks, electrical and electronics industries. Excessive environmental or occupational exposure to Ni may result in tumor, contact dermatitis, as well as damages to the nervous system. In recent years, more and more research has demonstrated that Ni induced nerve damages are related to mitochondrial dysfunction. In this paper, we try to characterize Ni induced neurotoxicity as well as the underlying mechanisms, and how to find new drugs for chemoprevention, by reviewing chemicals with neuroprotective effects on Ni induced neurotoxicity.

Ammonia-induced mitochondrial dysfunction and energy metabolism disturbances in isolated brain and liver mitochondria, and the effect of taurine administration: relevance to hepatic encephalopathy treatment

INTRODUCTION

Ammonia-induced oxidative stress, mitochondrial dysfunction, and energy crisis are known as some the major mechanisms of brain injury in hepatic encephalopathy (HE). Hyperammonemia also affects the liver and hepatocytes. Therefore, targeting mitochondria seems to be a therapeutic point of intervention in the treatment of HE. Taurine is an abundant amino acid in the human body. Several biological functions including the mitochondrial protective properties are attributed to this amino acid. The aim of this study is to evaluate the effect of taurine administration on ammonia-induced mitochondrial dysfunction.

MATERIAL AND METHODS

Isolated mice liver and brain mitochondria were exposed to different concentrations of ammonia (1, 5, 10, and 20 mM) and taurine (1, 5, and 10 mM), and several mitochondrial indices were assessed.

RESULTS

It was found that ammonia inhibited mitochondrial dehydrogenases activity caused collapse of mitochondrial membrane potential (MMP), induced mitochondrial swelling (MPP), and increased reactive oxygen species (ROS) in isolated liver and brain mitochondria. Furthermore, a significant amount of lipid peroxidation (LPO), along with glutathione (GSH) and ATP depletion, was detected in ammonia exposed mitochondria. Taurine administration (5 and 10 mM) mitigated ammonia-induced mitochondrial dysfunction.

CONCLUSIONS

The current investigation demonstrates that taurine is instrumental in preserving brain and liver mitochondrial function in a hyperammonemic environment. The data suggest taurine as a potential protective agent with a therapeutic capability against hepatic encephalopathy and hyperammonemia.

Nutritional and functional properties of fishmeal produced from fresh by-products of cod (Gadus morhua L.) and saithe (Pollachius virens)

Fresh by-products of whitefish such as cod and saithe is processed to fishmeal (FM) on-board seagoing Norwegian trawlers. The aim of this study was to document the properties of whitefish FM (WFM) protein with respect to, physicochemical and bioactive properties. Analysis of the proximate composition of representative seasonal WFM batches show that the production is robust without much variance. The mean protein (61.9 ± 1.2), fat (8.9 ± 1.1%), moisture (5 ± 1.2%) and ash content (22.4 ± 0.8%), reflect the use of lean and bony raw-material. The WFM has a low content of free amino acids (0.7%) and biogenic amines (< 1000 mg/kg) that confirm the high quality and freshness of the raw material. Amino-acid analysis identified the presence of all nutritionally essential amino acids. The WFM physicochemical properties was comparable to soy-bean meal (SBM) by analysis of solubility, water-holding capacity (WHC), the emulsion stability (ES). Proteolytic degradation of the WFM was used to demonstrate the presence of bioactive peptides with inhibiting activity against angiotensin-converting enzyme (ACE) activity, in vitro. Taken together, WFM produced from fresh by-products is an excellent protein source with attributes of interest beyond the aquafeed-market.

Beneficial effects of fermented sardinelle protein hydrolysates on hypercaloric diet induced hyperglycemia, oxidative stress and deterioration of kidney function in wistar rats

This study investigated the potential effects of fermented sardinelle protein hydrolysates (FSPHs) obtained by two proteolytic bacteria, Bacillus subtilis A26 (FSPH-A26) and Bacillus amyloliquefaciens An6 (FSPH-An6), on hypercaloric diet (HCD) induced hyperglycemia and oxidative stress in rats. Effects of FSPHs on blood glucose level, glucose tolerance, α-amylase activity and hepatic glycogen content were investigated, as well as their effect on the oxidative stress state. Biochemical findings revealed that, while undigested sardinelle proteins did not exhibit hypoglycemic activity, oral administration of FSPHs to HCD-fed rats reduced significantly α-amylase activity as well as glycemia and hepatic glycogen levels. Further, the treatment with FSPHs improved the redox status by decreasing the levels of lipid peroxidation products and increasing the activities of the antioxidant enzymes (superoxide dismutase, glutathione peroxidase and catalase) and the level of glutathione in the liver and kidneys, as compared to those of HCD-fed rats. FSPHs were also found to exert significant protective effects on liver and kidney functions, evidenced by a marked decrease in alkaline phosphatase activity and a modulation of creatinine and uric acid contents. These results indicated the beneficial effect of FSPHs on the prevention from hyperglycemia and oxidative stress.

Taurine treatment preserves brain and liver mitochondrial function in a rat model of fulminant hepatic failure and hyperammonemia

Ammonia-induced mitochondrial dysfunction and energy crisis is known as a critical consequence of hepatic encephalopathy (HE). Hence, mitochondria are potential targets of therapy in HE. The current investigation was designed to evaluate the role of taurine treatment on the brain and liver mitochondrial function in a rat model of hepatic encephalopathy and hyperammonemia. The animals received thioacetamide (400mg/kg, i.p, for three consecutive days at 24-h intervals) as a model of acute liver failure and hyperammonemia. Several biochemical parameters were investigated in the serum, while the animals' cognitive function and locomotor activity were monitored. Mitochondria was isolated from the rats' brain and liver and several indices were assessed in isolated mitochondria. Liver failure led to cognitive dysfunction and impairment in locomotor activity in the rats. Plasma and brain ammonia was high and serum markers of liver injury were drastically elevated in the thioacetamide-treated group. An assessment of brain and liver mitochondrial function in the thioacetamide-treated animals revealed an inhibition of succinate dehydrogenase activity (SDA), collapsed mitochondrial membrane potential, mitochondrial swelling, and increased reactive oxygen species (ROS). Furthermore, a significant decrease in mitochondrial ATP was detected in the brain and liver mitochondria isolated from thioacetamide-treated animals. Taurine treatment (250, 500, and 1000mg/kg) decreased mitochondrial swelling, ROS, and LPO. Moreover, the administration of this amino acid restored brain and liver mitochondrial ATP. These data suggest taurine to be a potential protective agent with therapeutic capability against hepatic encephalopathy and hyperammonemia-induced mitochondrial dysfunction and energy crisis.

Effects of S-Adenosylmethionine and Its Combinations With Taurine and/or Betaine on Glutathione Homeostasis in Ethanol-induced Acute Hepatotoxicity

Background

Exposure to ethanol abuse and severe oxidative stress are risk factors for hepatocarcinoma. The aim of this study was to evaluate the effects of S-adenosylmethionine (SAMe) and its combinations with taurine and/or betaine on the level of glutathione (GSH), a powerful antioxidant in the liver, in acute hepatotoxicity induced by ethanol.

Methods

To examine the effects of SAMe and its combinations with taurine and/or betaine on ethanol-induced hepatotoxicity, AML12 cells and C57BL/6 mice were pretreated with SAMe, taurine, and/or betaine, followed by ethanol challenge. Cell viability was detected with an MTT assay. GSH concentration and mRNA levels of GSH synthetic enzymes were measured using GSH reductase and quantitative real-time reverse transcriptase-PCR. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were measured with commercially available kits.

Results

Pretreatment of SAMe, with or without taurine and/or betaine, attenuated decreases in GSH levels and mRNA expression of the catalytic subunit of glutamate-cysteine ligase (GCL), the rate-limiting enzyme for GSH synthesis, in ethanol-treated cells and mice. mRNA levels of the modifier subunit of GCL and glutathione synthetase were increased in mice treated with SAMe combinations. SAMe, taurine, and/or betaine pretreatment restored serum ALT and AST levels to control levels in the ethanol-treated group.

Conclusions

Combinations of SAMe with taurine and/or betaine have a hepatoprotective effect against ethanol-induced liver injury by maintaining GSH homeostasis.

Quality changes of salmon by-products during storage: Assessment and quantification by NMR

Safe utilization of fish by-products is an important task due to increasing fish consumption. It can provide new valuable food/feed and will increase the economical profit and sustainability of the fishery industry. NMR spectroscopy is a reliable tool able to monitor qualitative and quantitative changes in by-products. In this work the trichloroacetic acid extracts of salmon backbones, heads and viscera stored at industrially relevant temperatures (4 and 10°C) were studied using NMR. Twenty-five metabolites were detected and the possibility of salmon by-products utilization as a source of anserine, phosphocreatine and taurine was discussed. Statistical data elaboration allowed determining the main processes occurring during by-products storage: formation of trimethylamine and biogenic amines, proteolysis and different types of fermentations. By-products freshness was evaluated using a multi-parameter approach: the trimethylamine and biogenic amines concentration changes were compared with Ki and H-values and safe temperatures and times for storage of salmon by-products were proposed.

Impact of an Energy Drink on the Structure of Stomach and Pancreas of Albino Rat: Can Omega-3 Provide a Protection?

BACKGROUND AND OBJECTIVES

A controversy developed between the benefits of energy drinks (EDs) versus the possible health threats since its revolution. Lack of information was a call to assess the effect of chronic consumption of Power Horse (PH) as one of the EDs, on the structure of pancreas and fundic mucosa of stomach in rats, and possible protective role of Omega-3.

MATERIALS AND METHODS

Thirty two adult male albino rats were divided equally into 4 groups; control received group which only received a standard diet, Omega-3 group, PH group which given PH and PH plus Omega-3 group received both PH plus Omega-3 for 4 weeks. Biochemical assessment of blood glucose, serum insulin, gastrin, tumor necrosis factor alpha (TNF-α) and inducible nitric oxide synthetase (iNOS) was performed. The antioxidant activity and histopathological examination of both pancreatic tissue and fundic mucosa of stomach were assessed.

RESULTS

Administration of PH significantly increased serum insulin and glucose levels while it significantly reduced serum gastrin level compared to control. PH also caused oxidants/antioxidants imbalance in both pancreas and fundic mucosa. The latter revealed degenerative changes and increased apoptosis which was evident by increased caspase-3 immunoexpression. Pancreas exhibited signs of β-cells overstimulation. Fundic mucosa showed reduced number of parietal cells, gastrin hormone expression compared to control group. Omega-3 administration could alleviate, to some extent, these changes. It significantly decreased TNF-α, iNOS and reduced glutathione (GSH) as well as significantly increasing superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities compared to the group which received PH alone.

CONCLUSION

Power Horse intake significantly injures islet cells, pancreatic acini as well as the glandular cells of the fundic mucosa. Omega-3 decreases these detrimental effects mostly through its antioxidant and anti-inflammatory action.

Metabolic disturbances in plasma as biomarkers for Huntington's disease

Huntington's disease (HD), caused by expanded CAG repeats encoding a polyglutamine tract in the huntingtin protein, presents with a predominant degeneration of neurons in the striatum and cortex. Although a few studies have identified substantial metabolite alterations in plasma, the picture of plasma metabolomics of HD has not been clearly depicted yet. Using a global metabolomics screening for plasma from 15 HD patients and 17 controls, HD patient group was separated from the control group by a panel of metabolites belonging to carnitine, amino acid and phosphatidylcholine species. The quantification of 184 related metabolites (including carnitine, amino acid and phosphatidylcholine species) in 29 HD patients, 9 presymptomatic HD carriers and 44 controls further showed one up-regulated (glycine) and 9 down-regulated metabolites (taurine, serotonin, valine, isoleucine, phosphatidylcholine acyl-alkyl C36:0 and C34:0 and lysophosphatidylcholine acyl C20:3). To understand the biosynthetic alterations of phosphatidylcholine in HD, we examined the expression levels and activities of a panel of key enzymes responsible for phosphatidylcholine metabolism. The results showed down-regulation of PCYT1A and increased activity of phospholipase A2 in HD leukocytes. These metabolic profiles strongly indicate that disturbed metabolism is involved in pathogenesis of HD and provide clue for the development of novel treatment strategies for HD.

Immunomodulatory properties of shellfish derivatives associated with human health

Some vital components of marine shellfish are documented as an important source for both nutritional and pharmacological applications.

Taurine Attenuates Hepatic Inflammation in Chronic Alcohol-Fed Rats Through Inhibition of TLR4/MyD88 Signaling

Accumulating evidence indicates that overconsumption of ethanol contributes in many ways to the pathogenesis of hepatic injury. Although studies indicate that taurine decreases lipogenesis, oxidative stress, and inflammatory cytokines, the protective effect of taurine against alcohol-induced liver injury is still unclear. To clarify the precise signaling involved in the beneficial effect of taurine on alcohol-induced liver injury, rats were randomly divided into four treatment groups: (1) control (Ctl), (2) alcohol (Alc), (3) Alc+taurine (Tau), and (4) Alc+silymarin (Sil). The Tau and Sil groups had lower lymphocyte infiltration and significantly lower TLR-4/MyD88 and IκB/NFκB compared to the Alc group. The inducible nitric oxide synthase (iNOS), C-reactive protein (CRP), tumor necrosis factors (TNF)-α, interleukin (IL)-6, and IL-1β were also significantly lower in the Tau and Sil groups than in the Alc group. The experimental results indicated that hepatoprotection against alcohol-induced inflammation may be mediated by decreased TLR-4/MyD88 signaling.

Methodological and metabolic considerations in the study of caffeine-containing energy drinks

Caffeine-containing energy drinks are popular and widely available beverages. Despite large increases in consumption, studies documenting the nutritional, metabolic, and health implications of these beverages are limited. This review provides some important methodological considerations in the examination of these drinks and highlights their potential impact on the gastrointestinal system, liver, and metabolic health. The gastrointestinal system is important as it comes into contact with the highest concentration of energy drink ingredients and initiates a chain of events to communicate with peripheral tissues. Although energy drinks have diverse compositions, including taurine, ginseng, and carnitine, the most metabolically deleterious ingredients appear to be simple sugars (such as glucose and fructose) and caffeine. In combination, these last two ingredients have the greatest metabolic impact and potential influence on overall health.

The neuroprotective effects of taurine against nickel by reducing oxidative stress and maintaining mitochondrial function in cortical neurons

Previous studies have indicated that oxidative stress and mitochondrial dysfunction are involved in the toxicity of nickel. Taurine is recognized as an efficient antioxidant and is essential for mitochondrial function. To investigate whether taurine could protect against the neurotoxicity of nickel, we exposed primary cultured cortical neurons to various concentrations of nickel chloride (NiCl2; 0.5mM, 1mM and 2mM) for 24h or to 1mM NiCl2 for various periods (0 h, 12h, 24h and 48 h). Our results showed that taurine efficiently reduced lactate dehydrogenase (LDH) release induced by NiCl2. Along with this protective effect, taurine pretreatment not only significantly reversed the increase of ROS production and mitochondrial superoxide concentration, but also attenuated the decrease of superoxide dismutase (SOD) activity and glutathione (GSH) concentration in neurons exposed to NiCl2 for 24h. Moreover, nickel exposure reduced ATP production, disrupted the mitochondrial membrane potential and decreased mtDNA content. These types of oxidative damage in the mitochondria were efficiently ameliorated by taurine pretreatment. Taken together, our results indicate that the neuroprotective effects of taurine against the toxicity of nickel might largely depend on its roles in reducing oxidative stress and improving mitochondrial function. Taurine may have great pharmacological potential in treating the adverse effects of nickel in the nervous system.

Taurine Concentrations Decrease in Critically Ill Patients With Shock Given Enteral Nutrition

BACKGROUND

Nutrition studies in the intensive care unit (ICU) have shown that adequate enteral nutrition (EN) support has clinical benefits. However, the course of amino acid concentrations in plasma has never been investigated in patients admitted with shock receiving EN. We hypothesized that plasma concentrations, when deficit, increase during EN and that persistent deficiency is associated with poor outcome.

METHODS

In 33 septic or cardiogenic shock patients receiving EN, plasma amino acid concentrations were measured during 5 days. Changes in amino acid concentrations, correlations with clinical outcome variables, and regression analyses were studied.

RESULTS

On ICU admission, several plasma concentrations were deficient. Plasma concentrations of almost all amino acids increased. In contrast, taurine decreased by >50%, from 47.6 µmol/L on admission to 20.0 µmol/L at day 1, and remained low at day 5. Taurine (admission) correlated with time on mechanical ventilation (R = -0.42, P = .015). Taurine decrease within 24 hours correlated with Acute Physiology and Chronic Health Evaluation II predicted mortality (R = 0.43, P = .017) and Sequential Organ Failure Assessment score (R = 0.36, P = .05). Regression analyses confirmed correlations.

CONCLUSIONS

Several amino acids were deficient in plasma on ICU admission but increased during EN. Taurine concentrations declined and were associated with longer periods of mechanical ventilation and ICU support. Fast taurine decline correlated with severity of organ failure. These findings support the role of taurine during ischemia, reperfusion, and inflammation. Taurine may be an essential candidate to enrich nutrition support for critically ill patients, although more research is required.

Characterization of protein, lipid and mineral contents in common Norwegian seaweeds and evaluation of their potential as food and feed

BACKGROUND

The objectives of this study were to examine protein and amino acid composition, lipid and fatty acid composition, along with a range of essential minerals in common Norwegian seaweed species representing the red (Palmaria palmata and Vertebrata lanosa), green (Cladophora rupestris, Enteromorpha intestinalis and Ulva lactuca) and brown (Alaria esculenta, Laminaria digitata, Laminaria hyperborea, Fucus vesiculosus and Pelvetia canaliculata) classes and assess their potential as alternatives to cereals in food and feed. As macroalgae accumulate heavy metals, arsenic, cadmium and mercury were also analyzed.

RESULTS

Proteins ranged from 34 to 123 g kg(-1) dry weight (DW) and the essential amino acid levels may cover both human and salmonid requirements. Lipids were low (6-58 g kg(-1) DW), but the red algae had high relative content of long-chained omega-3 fatty acids (32-34 % of the fatty acids). Iodine contents were particularly high in the Laminaria species. Of the heavy metals only arsenic levels may be of concern.

CONCLUSION

In total, the red alga P. palmata was regarded as the best alternative to cereals in food and feed. For several of the other species, single-component extraction for the ingredients market may be better than using the whole product.

Mechanisms Underlying Taurine Protection Against Glutamate-Induced Neurotoxicity

Taurine appears to exert potent protections against glutamate (Glu)-induced injury to neurons, but the underlying molecular mechanisms are not fully understood. The possibly protected targets consist of the plasma membrane and the mitochondrial as well as endoplasmic reticulum (ER) membranes. Protection may be provided through a variety of effects, including the prevention of membrane depolarization, neuronal excitotoxicity and mitochondrial energy failure, increases in intracellular free calcium ([Ca2+]i), activation of calpain, and reduction of Bcl-2 levels. These activities are likely to be linked spatially and temporally in the neuroprotective functions of taurine. In addition, events that occur downstream of Glu stimulation, including altered enzymatic activities, apoptotic pathways, and necrosis triggered by the increased [Ca2+]i, can be inhibited by taurine. This review discusses the possible molecular mechanisms of taurine against Glu-induced neuronal injury, providing a better understanding of the protective processes, which might be helpful in the development of novel interventional strategies.