Taurine reduces inflammatory responses after spinal cord injury

Inflammation: A Target for Treatment in Spinal Cord Injury

Spinal cord injury (SCI) is a significant cause of disability, and treatment alternatives that generate beneficial outcomes and have no side effects are urgently needed. SCI may be treatable if intervention is initiated promptly. Therefore, several treatment proposals are currently being evaluated. Inflammation is part of a complex physiological response to injury or harmful stimuli induced by mechanical, chemical, or immunological agents. Neuroinflammation is one of the principal secondary changes following SCI and plays a crucial role in modulating the pathological progression of acute and chronic SCI. This review describes the main inflammatory events occurring after SCI and discusses recently proposed potential treatments and therapeutic agents that regulate inflammation after insult in animal models.

Triad1 Promotes the Inflammatory Response and Neuronal Apoptosis to Aggravate Acute Spinal Cord Injury in Rats

Objective

Spinal cord injury (SCI) is one of the most devastating central injuries, resulting in serious locomotor deficits. Triad1 is known to play an important role in SCI, but its effects on the inflammatory response and physiological behavior have not been thoroughly studied. This study is aimed at examining the effects of Triad1 on the inflammatory response and neuronal injury in acute SCI in rats.

Methods

Twenty-four male Sprague–Dawley (SD) rats were randomly divided into a control group, SCI group, sh-NC group, and Triad1 knockout group (sh-Triad1). The Basso Beattie Bresnahan locomotor rating scale was utilized for the assessment of the motor ability of rats. Hematoxylin and eosin (H&E), Luxol fast blue (LFB), and TUNEL staining were used to assess the pathological injury, demyelination, and neuronal apoptosis, respectively. ELISA was used to detect the levels of IL-1β, IL-10, and TNF-α, and qRT-PCR was used to examine the expression level of Triad1. Furthermore, the protein levels of Triad1, Bax, Bcl-2, and cleaved caspase-3 were determined using western blotting.

Results

The Triad1 expression level was upregulated in damaged spinal cord tissue. Knockdown of Triad1 improved motor function and reduced SCI as well as apoptosis of spinal cord neurons. In addition, the knockdown of Triad1 inhibited the inflammatory response caused by SCI.

Conclusion

Knockdown of Triad1 can reduce SCI in rats with acute SCI by inhibiting the inflammatory response and apoptosis.

N-Chlorotaurine Reduces the Lung and Systemic Inflammation in LPS-Induced Pneumonia in High Fat Diet-Induced Obese Mice

Lung infection can evoke pulmonary and systemic inflammation, which is associated with systemic severe symptoms, such as skeletal muscle wasting. While N-chlorotaurine (also known as taurine chloramine; TauCl) has anti-inflammatory effects in cells, its effects against pulmonary and systemic inflammation after lung infection has not been elucidated. In the present study, we evaluated the anti-inflammatory effect of the taurine derivative, TauCl against Escherichia coli-derived lipopolysaccharide (LPS)-induced pneumonia in obese mice maintained on a high fat diet. In this study, TauCl was injected intraperitoneally 1 h before intratracheal LPS administration. While body weight was decreased by 7.5% after LPS administration, TauCl treatment suppressed body weight loss. TauCl also attenuated the increase in lung weight due to lung edema. While LPS-induced acute pneumonia caused an increase in cytokine/chemokine mRNA expression, including that of IL-1β, -6, TNF-α, MCP-1, TauCl treatment attenuated IL-6, and TNF-alpha expression, but not IL-1β and MCP-1. TauCl treatment partly attenuated the elevation of the serum cytokines. Furthermore, TauCl treatment alleviated skeletal muscle wasting. Importantly, LPS-induced expression of Atrogin-1, MuRF1 and IκB, direct or indirect targets for NFκB, were suppressed by TauCl treatment. These findings suggest that intraperitoneal TauCl treatment attenuates acute pneumonia-related pulmonary and systemic inflammation, including muscle wasting, in vivo.

Taurine alleviates endoplasmic reticulum stress, inflammatory cytokine expression and mitochondrial oxidative stress induced by high glucose in the muscle cells of olive flounder (Paralichthysolivaceus)

The aim of the present study was to evaluate the effects of taurine on endoplasmic reticulum stress, inflammatory cytokine expression and mitochondrial oxidative stress induced by high glucose in primary cultured muscle cells of olive flounder (Paralichthys olivaceus). Three experimental groups were designed as follows: muscle cells of olive flounder incubated with three kinds of medium containing 5 mM glucose (control), 33 mM glucose (HG) or 33 mM glucose + 10 mM taurine (HG + T), respectively. Results showed that taurine addition significantly alleviated the decreased activity of superoxide dismutase (SOD) and the ratio of reduced to oxidized glutathione (GSH/GSSG) induced by high glucose. The increase of cellular reactive oxygen species (ROS), malondialdehyde content and cell apoptosis induced by high glucose were alleviated by taurine. Besides, gene expression of glucose-regulated protein 78, PKR-like ER kinase, tumor necrosis factor-α, interleukin-6, interleukin-1β, interleukin-8, muscle atrophy F-box protein and muscle RING-finger protein 1 were significantly up-regulated in the HG group, and taurine addition decreased the expression of these genes. High glucose led to the swelling of the endoplasmic reticulum (ER). Meanwhile, the nuclear translocation of nuclear factor κB (NF-κB) and the release of cytochrome C from mitochondria induced by high glucose were suppressed by taurine addition. These results demonstrated that taurine alleviated ERS, inflammation and mitochondrial oxidative stress induced by high glucose in olive flounder muscle cells. The ROS production, NF-κB signaling pathway and mitochondria function were the main targets of the biological effects of taurine under high glucose condition.

Taurine Supplementation as a Neuroprotective Strategy upon Brain Dysfunction in Metabolic Syndrome and Diabetes

Obesity, type 2 diabetes, and their associated comorbidities impact brain metabolism and function and constitute risk factors for cognitive impairment. Alterations to taurine homeostasis can impact a number of biological processes, such as osmolarity control, calcium homeostasis, and inhibitory neurotransmission, and have been reported in both metabolic and neurodegenerative disorders. Models of neurodegenerative disorders show reduced brain taurine concentrations. On the other hand, models of insulin-dependent diabetes, insulin resistance, and diet-induced obesity display taurine accumulation in the hippocampus. Given the possible cytoprotective actions of taurine, such cerebral accumulation of taurine might constitute a compensatory mechanism that attempts to prevent neurodegeneration. The present article provides an overview of brain taurine homeostasis and reviews the mechanisms by which taurine can afford neuroprotection in individuals with obesity and diabetes. We conclude that further research is needed for understanding taurine homeostasis in metabolic disorders with an impact on brain function.

Therapeutic Induction of Energy Metabolism Reduces Neural Tissue Damage and Increases Microglia Activation in Severe Spinal Cord Injury

Neural tissue has high metabolic requirements. Following spinal cord injury (SCI), the damaged, tissue suffers from a severe metabolic impairment, which aggravates axonal degeneration and, neuronal loss. Impaired cellular energetic, tricarboxylic acid (TCA) cycle and oxidative, phosphorylation metabolism in neuronal cells has been demonstrated to be a major cause of neural tissue death and regeneration failure following SCI. Therefore, rewiring the spinal cord cell metabolism may be an innovative therapeutic strategy for the treatment of SCI. In this study, we evaluated the therapeutic effect of the recovery of oxidative metabolism in a mouse model of severe contusive SCI. Oral administration of TCA cycle intermediates, co-factors, essential amino acids, and branched-chain amino acids was started 3 days post-injury and continued until the end of the experimental procedures. Metabolomic, immunohistological, and biochemical analyses were performed on the injured spinal cord sections. Administration of metabolic precursors enhanced spinal cord oxidative metabolism. In line with this metabolic shift, we observed the activation of the mTORC1 anabolic pathway, the increase in mitochondrial mass, and ROS defense which effectively prevented the injury-induced neural cell apoptosis in treated animals. Consistently, we found more choline acetyltransferase (ChAT)-expressing motor neurons and increased neurofilament positive corticospinal axons in the spinal cord parenchyma of the treated mice. Interestingly, oral administration of the metabolic precursors increased the number of activated microglia expressing the CD206 marker suggestive of a, pro-resolutive, M2-like phenotype. These molecular and histological modifications observed in treated animals ultimately led to a significant, although partial, improvement of the motor functions. Our data demonstrate that rewiring the cellular metabolism can represent an effective strategy to treat SCI.

The nephroprotective properties of taurine-amikacin treatment in rats are mediated through HSP25 and TLR-4 regulation

Amikacin (AMK) is one of the most effective aminoglycoside antibiotics. However, nephrotoxicity is a major deleterious and dose-limiting side effect associated with its clinical use especially in high dose AMK-treated patients. The present study assessed the ability of taurine (TAU) to alleviate or prevent AMK-induced nephrotoxicity if co-administrated with AMK focusing on inflammation, apoptosis, and fibrosis. Male Sprague Dawley rats were assigned to six equal groups. Group 1: rats received saline (normal control), group 2: normal rats received 50 mg kg^-1 TAU intraperitoneally (i.p.). Groups 3 and 4: received AMK (25 or 50 mg kg^-1; i.p.). Groups 5 and 6: received TAU (50 mg kg^-1; i.p.) concurrently with AMK (25 or 50 mg kg^-1; i.p.) for 3 weeks. AMK-induced nephrotoxicity is evidenced by elevated levels of serum creatinine (CRE), blood urea nitrogen (BUN), and uric acid (UA). Histopathological investigations provoked damaging changes in the renal tissues. Heat shock proteins (HSP)25 and Toll-like receptor-4 (TLR-4) elevated levels were involved in the induction of inflammatory reactions and focal fibrosis. The improved activation of TLR-4 may stimulate monocytes to upgrade Interleukin (IL)-18 production rather than IL-10. TAU proved therapeutic effectiveness against AMK-induced renal toxicity through downregulation of HSP25, TLR-4, caspase-3, and IL-18 with up-regulation of IL-10 levels.

Effect of taurine associated gold nanoparticles on oxidative stress in muscle of mice exposed to overuse model

Muscle overuse and its consequent muscle damage has no cure. Therefore, the present study aimed to investigate the regulatory role of tau-AuNPs on muscle recovery of muscle overuse model. The animals (Male Swiss mice) were randomly divided into four groups: Control (Ctr; n=6); tau-AuNPs (n=6); overuse (n=6); and overuse plus tau-AuNPs (n=6). Exercise sessions were performed for 21 consecutive days, and one exercise model was applied daily in the following sequence: low intensity, moderate intensity, and high intensity. The mice were then sacrificed. The quadriceps muscles were surgically removed for subsequent biochemical analysis (oxidative stress parameters, DNA damage markers and muscle differentiation protein). The overuse group significantly increased the oxidative stress parameters and DNA damage markers, whereas tau-AuNPs significantly decreased the oxidative stress parameters in the overuse animal model. However, there were no significant differences observed between overuse group and overuse plus tau-AuNPs administrated group in relation to DNA damage markers including DNA damage frequency and index levels when compared to control and tau-AuNPs groups. Muscle differentiation protein Myf-5 was increased in the overuse plus tau-AuNPs administration group when compared to control group. In conclusion, tau-AuNPs had significant effect on reducing oxidative stress parameters and increasing myogenic regulatory protein Myf-5 in the overuse group. However, it did not have significant effect on reducing DNA damage.

A systematic review of preclinical studies on the efficacy of taurine for the treatment of rheumatoid arthritis

Due to the undesirable effects of conventional medical therapies prescribed for rheumatoid arthritis (RA), complementary therapies, especially nutritional agents, have recently gained great attention. Recent animal and in vitro researches have shown benefits of taurine (Tau), a sulfur-containing amino acid, in RA and suggest that Tau may be a therapeutic candidate in RA; however, no systematic review exists regarding Tau and RA. Accordingly, this paper systematically reviewed the available researches regarding Tau and RA and plausible underlying mechanisms. We searched electronic databases like Scopus, WOS, PubMed, Embase, ProQuest, Cochrane Library, and a search engine Google Scholar until December 2020 and we have applied search alert services to detect related papers published after the primary search. We did not have any restriction in publication date and/or language. We found no clinical study; thus we considered related animal and in vitro researches. Furthermore, we checked the citations or references of these researches and grey literature to detect possible studies. We did not consider reviews, book chapters, conference abstracts, and articles about Tau in health problems other than RA. Eighteen articles were entered in present systematic review. Animal and in vitro researches showed that Tau either directly or indirectly (via Tau derivatives such as Tau-chloramine, Tau-bromamine, taurochenodeoxycholic acid, and taurolidine) could control RA by different mechanisms such as reducing inflammation, suppressing oxidative stress, and inducing apoptosis. This review serves convincing clues about the efficacy of Tau in RA and explains the importance of additional clinical investigations.

Bromamine T, a stable active bromine compound, prevents the LPS‑induced inflammatory response

Inflammation is the most common cause of most acute and chronic debilitating diseases. Towards unveiling novel therapeutic options for patients with such complications, N‑bromotaurine (TauNHBr) has emerged as a potential anti‑inflammatory agent; however, its therapeutic efficacy is hindered due to its relatively poor stability. To address this challenge, the present study focused on examining the effects of a stable active bromine compound, named bromamine T (BAT). The present study examined the protective properties of BAT against lipopolysaccharide (LPS)‑mediated inflammation in vitro, by using LPS‑stimulated murine J774.A1 macrophages (Mφs), as well as in vivo, by using a murine LPS‑mediated air‑pouch model. Additionally, its efficacy was compared with that of taurine, a known potent anti‑inflammatory molecule. In LPS‑stimulated J774A.1 Mφs, BAT and taurine were very effective in reducing the secretion of pro‑inflammatory mediators. The in vitro experiments indicated that LPS‑mediated inflammation was attenuated due to the protective properties of BAT and of taurine, probably through the inhibition of phosphorylated p65 NF‑κB subunit (Ser 536) nuclear translocation. The in vivo experiments also revealed that BAT and taurine inhibited LPS‑mediated inflammation by reducing total cell/polymorphonuclear cell (PMN) infiltration in the air‑pouch and by decreasing pouch wall thickness. The analysis of exudates obtained from pouches highlighted that the inhibitory effects of BAT and taurine on the secretion of pro‑inflammatory cytokines were similar to those observed in vitro. Notably, the effect of BAT at the highest concentration tested was superior to that of taurine at the highest concentration. Taken together, the findings of the present study indicate that BAT prevents the LPS‑induced inflammatory response both in vitro and in vivo.

Taurine supplementation reduces myeloperoxidase and matrix-metalloproteinase-9 levels and improves the effects of exercise in cognition and physical fitness in older women

Immunosenescence contributes to cognitive impairment and neurodegeneration, and those conditions could be attenuated by non-pharmacological anti-inflammatory strategies, such as exercise and supplementation with the amino acid taurine. Since taurine body content decreases with aging, we investigated the effects of supplementation (alone and combined with exercise) on oxidative stress, extracellular matrix degradation, white blood cells, neurotrophins, cognition and physical fitness of elderly women. Forty-eight women (83.58 ± 6.98 years) were enrolled into exercise training only (EO: n = 13), taurine supplementation (TS: n = 12), exercise training + taurine supplementation (ETTS: n = 11), and control group (CG: n = 12). All interventions lasted 14 weeks. Exercise was applied twice a week, and taurine was given once a day (1.5 g). Data collection occurred before and after interventions with the determination of myeloperoxidase (MPO), matrix metalloproteinase-9 (MMP-9), brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF) levels, and white blood cell counts (WBC). Montreal cognitive assessment (MoCA) and physical fitness tests were also evaluated. Concentration of MPO and MMP-9 decreased after intervention in TS (p < 0.05). No effect of time or time × group was observed for WBC parameters; however, univariate analysis showed a significant decrease in lymphocytes for TS, while an increase in monocytes occurred in the CG (p < 0.05). MoCA scores decreased over time in the CG (p < 0.05). Improvements in physical fitness occurred in ETTS (better agility and aerobic capacity), mostly likely due to exercise and boosted by taurine supplementation. No changes in BDNF levels were observed (p > 0.05), while NGF concentration were undetectable in almost subjects. Exercise together with taurine supplementation appears to be a valuable strategy to enhance health-related outcomes in older persons.

Dietary taurine supplementation attenuates lipopolysaccharide-induced inflammatory responses and oxidative stress of broiler chickens at an early age

This study was conducted to investigate the effect of taurine as a prophylactic treatment on antioxidant function and inflammatory responses of broilers challenged with lipopolysaccharide (LPS). A total of 256 one-day-old male Arbor Acres broiler chicks were randomly assigned to four treatments with eight replicates of eight birds (eight birds per cage). Four treatment groups were designated as follows: 1) in the CON group, broilers fed a basal diet; 2) in the LPS group, LPS-challenged broilers fed a basal diet; 3) in the LPS + T1 group, LPS-challenged broilers fed a basal diet supplemented with 5.0 g/kg taurine; and 4) in the LPS + T2 group, LPS-challenged broilers fed a basal diet supplemented with 7.5 g/kg taurine. The LPS-challenged broilers were intraperitoneally injected with 1 mg/kg body weight (BW) of LPS at 16, 18, and 20 d of age, whereas the CON group received an injection of sterile saline. The results showed that broilers injected with LPS exhibited decreased (P < 0.05) the average daily gain (ADG) and the 21-d BW (P < 0.05), while taurine supplementation alleviated the negative effects of LPS. Additionally, the LPS-induced increases (P < 0.05) in serum alanine transaminase and aspartate transaminase activities were reversed by taurine supplementation. The taurines could alleviate the hepatic oxidative stress, with the presence of lower content of malondialdehyde (P < 0.05), higher content of glutathione (P < 0.05), and an increased glutathione peroxidase (GSH-Px) activity (P < 0.05). The concentrations of interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) in the liver were measured by ELISA kits, and the result showed that dietary taurine supplementation prevented these cytokines increases in the liver of LPS-induced broilers. Taurine reduced the genes expression of IL-1β, TNF-α, IL-6, cyclooxygenase-2, and inducible nitric oxide synthase, whereas it boosted the expression levels of antioxidant-related genes (nuclear factor erythroid 2-related factor 2, heme oxygenase-1, glutamate-cysteine ligase catalytic subunit, and GSH-Px) in the liver of LPS-induced broilers. In conclusion, dietary taurine supplementation in broilers mitigated LPS-induced defects in ADG, oxidative stress, and inflammatory responses.

The Anti-Inflammatory Effect of Taurine on Cardiovascular Disease

Taurine is a non-protein amino acid that is expressed in the majority of animal tissues. With its unique sulfonic acid makeup, taurine influences cellular functions, including osmoregulation, antioxidation, ion movement modulation, and conjugation of bile acids. Taurine exerts anti-inflammatory effects that improve diabetes and has shown benefits to the cardiovascular system, possibly by inhibition of the renin angiotensin system. The beneficial effects of taurine are reviewed.

Role of taurine, its haloamines and its lncRNA TUG1 in both inflammation and cancer progression. On the road to therapeutics? (Review)

For one century, taurine is considered as an end product of sulfur metabolism. In this review, we discuss the beneficial effect of taurine, its haloamines and taurine upregulated gene 1 (TUG1) long non‑coding RNA (lncRNA) in both cancer and inflammation. We outline how taurine or its haloamines (N‑Bromotaurine or N‑Chlorotaurine) can induce robust and efficient responses against inflammatory diseases, providing insight into their molecular mechanisms. We also provide information about the use of taurine as a therapeutic approach to cancer. Taurine can be combined with other chemotherapeutic drugs, not only mediating durable responses in various malignancies, but also circumventing the limitations met from chemotherapeutic drugs, thus improving the therapeutic outcome. Interestingly, the lncRNA TUG1 is regarded as a promising therapeutic approach, which can overcome acquired resistance of cancer cells to selected strategies. In this regard, we can translate basic knowledge about taurine and its TUG1 lncRNA into potential therapeutic options directed against specific oncogenic signaling targets, thereby bridging the gap between bench and bedside.

ddhCTP produced by the radical-SAM activity of RSAD2 (viperin) inhibits the NAD+ -dependent activity of enzymes to modulate metabolism

Radical S-adenosylmethionine (SAM) domain-containing protein 2 (RSAD2; viperin) is a key enzyme in innate immune responses that is highly expressed in response to viral infection and inflammatory stimuli in many cell types. Recently, it was found that RSAD2 catalyses transformation of cytidine triphosphate (CTP) to its analogue 3'-deoxy-3',4'-didehydro-CTP (ddhCTP). The cellular function of this metabolite is unknown. Here, we analysed the extra- and intracellular metabolite levels in human induced pluripotent stem cell (hiPSC)-derived macrophages using high-resolution LC-MS/MS. The results together with biochemical assays and molecular docking simulations revealed that ddhCTP inhibits the NAD⁺ -dependent activity of enzymes including that of the housekeeping enzyme glyceraldehyde 3-phosphate dehydrogenase (GAPDH). We propose that ddhCTP regulates cellular metabolism in response to inflammatory stimuli such as viral infection, pointing to a broader function of RSAD2 than previously thought.

Synergistic effect of ascorbic acid and taurine in the treatment of a spinal cord injury-induced model in rats

Spinal cord injury (SCI) results in severe damage, which causes functional alterations together with loss of autonomic functions, sensations, and muscle functioning. This injury leads to apoptosis of neurons and oligodendrocytes, which further leads to dysfunction of the spinal cord due to axonal degeneration and demyelination. Taurine is non-proteogenic and an essential amino acid, which plays a major role in the growth and development of brain cells. Ascorbic acid, also known as vitamin C, is found in various foods and is known to prevent scurvy. In this study, we have investigated the therapeutic effect of ascorbic acid and taurine against SCI-induced rats. The rats were divided into the following groups: sham, control, 100 mg/kg of taurine, 100 mg/kg of ascorbic acid, and 100 mg/kg of taurine + 100 mg/kg of ascorbic acid. Treatment was continued daily for 45 consecutive days. The combined treatment of taurine and ascorbic acid decreased caspase-3, bax, pro-NGF, and p53 mRNA expression by more than 30% compared to individual treatments. The combined treatment of taurine and ascorbic acid reduced caspase-3 and p53 expression by 33.7% and 44%, respectively, compared to individual treatments. The combined treatment of taurine and ascorbic acid decreased mRNA expression of interleukin-6 (IL-6), cyclooxygenase-2, tumor necrosis factor-alpha (TNF-α), and inducible nitric oxide synthase (iNOS) compared to the individual treatments of taurine and ascorbic acid. The combined treatment of taurine and ascorbic acid also significantly recovered altered antioxidant markers, and induced lipid peroxidation to near normal levels. In summary, apoptotic, inflammatory and oxidative stress markers were significantly decreased in SCI-induced rats treated with taurine and ascorbic acid.

A Novel Approach towards Synthesis and Characterization of Non-Cytotoxic Gold Nanoparticles Using Taurine as Capping Agent

Metal gold nanoparticles are of great interest due to their unique physico-chemical properties and their potential to be used as nano-probes in biosensors, drug delivery, and therapeutic applications. Currently, many capping agents are used for metal gold nanoparticles, such as cetyltrimethylammonium bromide (CTAB) and tri-sodium citrate that have been reported to be toxic and hinders biological applications. To address this issue, we report, for the first time, the use of taurine as a stable non-cytotoxic capping agent for synthesizing gold nanoparticles by using an in situ wet-chemical method. This facile method resulted in monodisperse gold nanospheres with a high yield and stability. Monodisperse gold nanospheres with average diameters of 6.9 nm and 46 nm were synthesized at a high yield with controlled morphology. Temperature played a critical role in determining the size of the taurine-capped gold nanoparticles. The subtle changes in the reaction parameters had a tremendous effect on the final size of nanoparticles and their stability. The synthesized nanoparticles were characterized by using optical spectroscopy, a ZetaSizer, a NanoSight, Fourier Transform Infrared (FTIR) spectroscopy, X-ray Diffraction (XRD), X-ray Photon Spectroscopy (XPS) and Electron Microscopy to understand their physico-chemical properties. Taurine was explored as a capping and stabilizing agent for gold nanospheres, which were evaluated for their toxicity responses towards human liver carcinoma cells (HepG2) via MTT assay.

A combined treatment of curcumin, piperine, and taurine alters the circulating levels of IL-10 and miR-21 in hepatocellular carcinoma patients: a pilot study

Background

Investigating and evaluating possible alternative therapeutic strategies to control hepatocellular carcinoma (HCC) is a critical need because of its high prevalence and being one of the most lethal cancers. Curcumin and taurine showed potent anti-tumor activities in pre-clinical and clinical studies by targeting multiple pathways. Thus, this study was designed to assess the effect of a combined treatment consisted of curcumin, piperine, and taurine on circulating levels of interleukin-10 (IL-10), and microRNAs miR-141 and miR-21.

Methods

Twenty eligible HCC patients administrated an oral dose of 4 g curcumin, 40 mg piperine, and 500 mg taurine daily for three successive treatment cycles, each was a 30-day. The level of IL-10 along with the expression levels of miR-141, and miR-21 were monitored in serum before starting the treatment and after each cycle. Patients were followed-up for a period of 24 months.

Results

The combined treatment was able to produce a significant decrease in the levels of serum IL-10, and miR-21 while it resulted in a non-significant up-regulation of serum miR-141 expression level. At the end of the follow-up period, the median overall survival (OS) rate was found to be 17.00 months with a worse OS in patients with high baseline levels of circulating IL-10 and miR-21 compared to those with low levels. In contrast, a low baseline level of circulating miR-141 was associated with poor prognosis.

Conclusions

The combined treatment may be able to increase the OS rate by altering the circulating level of IL-10 and miR-21.

Taurine and its analogs in neurological disorders: Focus on therapeutic potential and molecular mechanisms

Taurine is a sulfur-containing amino acid and known as semi-essential in mammals and is produced chiefly by the liver and kidney. It presents in different organs, including retina, brain, heart and placenta and demonstrates extensive physiological activities within the body. In the several disease models, it attenuates inflammation- and oxidative stress-mediated injuries. Taurine also modulates ER stress, Ca2+ homeostasis and neuronal activity at the molecular level as part of its broader roles. Different cellular processes such as energy metabolism, gene expression, osmosis and quality control of protein are regulated by taurine. In addition, taurine displays potential ameliorating effects against different neurological disorders such as neurodegenerative diseases, stroke, epilepsy and diabetic neuropathy and protects against injuries and toxicities of the nervous system. Several findings demonstrate its therapeutic role against neurodevelopmental disorders, including Angelman syndrome, Fragile X syndrome, sleep-wake disorders, neural tube defects and attention-deficit hyperactivity disorder. Considering current biopharmaceutical limitations, developing novel delivery approaches and new derivatives and precursors of taurine may be an attractive option for treating neurological disorders. Herein, we present an overview on the therapeutic potential of taurine against neurological disorders and highlight clinical studies and its molecular mechanistic roles. This article also addresses the neuropharmacological potential of taurine analogs.

Napabucasin prevents brain injury in neuronal neonatal rat cells through suppression of apoptosis and inflammation

The present study investigates the protective effect of napabucasin on the expression of apoptosis markers and inflammatory factors in the neuronal rat cells with post-isolation damage. The level of ROS determined by the fluorescence measurement in the neuronal rat cells with post-isolation damage was 310.21 RFU compared to 21.45 RFU in sham cell cultures. Napabucasin treatment decreased ROS level in the neuronal rat cells with post-isolation damage in dose based manner. ROS level decreased to 278.67, 203.65, 163.32 and 26.87 RFU, respectively in 1, 2, 3 and 4 μM napabucasin treated cell cultures. Treatment with napabucasin increased GSH level significantly (P < 0.05) in the neuronal rat cells with post-isolation damage. Napabucasin treatment at with 1, 2, 3 and 4 μM concentrations increased SOD activity to 2.4, 3.6, 5.1 and 6.1 U/mg, respectively. Treatment with napabucasin increased the activity of catalase in dose based manner. Napabucasin treatment increased Gpx in injured brain cells of neonatal rats. A significant (P < 0.05) increase in the activity of AChE was observed in neuronal rat cells with post-isolation damage on treatment with napabucasin. Treatment with napabucasin reduced the level of TNF-α and IL-6 significantly (P < 0.05) compared to untreated group. Napabucasin treatment decreased the expression of Bax, caspase-3 and p53 proteins in the neuronal rat cells with post-isolation damage. Napabucasin treatment protects post-isolation damage in the neuronal cells of neonatal rats by suppression of apoptosis and oxidative stress. Therefore, napabucasin can be used for the treatment of brain injury.

Taurine Attenuates Doxorubicin-Induced Toxicity on B16F10 Cells

This study aimed to investigate the effect of doxorubicin co-treatment with taurine on B16F10 melanoma cells. Frequently, Doxorubicin is used in the treatments of many different kinds of cancers, some of which are soft tissue sarcomas, hematological malignancies and carcinomas. However, the clinical application of doxorubicin is compromised by its severe adverse effects, including cardiotoxicity. In the present study, the efficacy of doxorubicin co-treatment with taurine was investigated. B16F10 cell viability was evaluated using MTT assays, trypan blue dye exclusion assays, and fluorescent staining technique. Apoptotic cells were detected by flow cytometry and the proteins associated with apoptosis and cellular differentiations were assessed by immunoblotting. Doxorubicin inhibited cell growth and induced cell death in B16F10 cells. Interestingly, doxorubicin co-treatment with taurine inhibited apoptosis in B16F10 cells. These results indicate that doxorubicin co-treatment with taurine attenuates doxorubicin-induced cytotoxicity and reduces ROS production in B16F10 cells.

Protective effects of taurine against inflammation, apoptosis, and oxidative stress in brain injury

The protective effect of taurine against inflammation, apoptosis and oxidative stress in traumatic brain injury was investigated in the present study. Taurine is a non-proteogenic and essential amino acid in animals. It plays a critical nutritional role in brain cell growth, differentiation, and development. Taurine is involved in regeneration and neuroprotection in the injured nervous system, and is an effective antioxidant against lead-, cadmium-, and exercise-induced oxidative stress. Astrocytes and neuron cells were co-cultured and cells were treated with different concentrations of taurine (100, 200 and 300 mg/l) for 72 h, and the levels of reactive oxygen species, malondialdehyde, reduced glutathione, glutathione peroxidase, superoxide dismutase, catalase, acetylcholinesterase, tumor necrosis factor-α, interleukin-6, caspase-3, p53, B-cell lymphoma 2 and Bcl-2-associated X protein were determined. These inflammatory, apoptotic, and oxidative stress markers were substantially increased in injured cells, and returned to normal levels following taurine supplementation. Thus, taurine supplementation may be effective against oxidative stress, apoptosis, and inflammation in injured brain cells.

High dose Allura Red, rather than the ADI dose, induces structural and behavioral changes in the medial prefrontal cortex of rats and taurine can protect it

Allura Red is a food color that can lead to neurotoxicity. Taurine is an organic compound that can act as a neuroprotectant. This study aimed to assess the effects of Allura Red with or without taurine consumption on rats' medial Prefrontal Cortex (mPFC). The subjects were divided into six groups as follows: distilled water, taurine (200 mg/kg/day), and low (7 mg/kg/day = acceptable daily dose), and high (70 mg/kg/day) doses of Allura Red with or without taurine consumption for six weeks. The results of novel objects recognition and eight-arm radial maze tests indicated impairment of memory in the Allura Red groups. Subsequently, their brains were analyzed using stereological methods. Both doses of Allura Red caused an increase in working and reference memory errors during the acquisition and retention phases in comparison to the distilled water group (p < 0.01). Additionally, the high dose of Allura Red led to a reduction in the volume of mPFC (35%) and its subdivisions, number of neurons (59%) and glial cells (46%), length of dendrites, and number of spines (mushroom and thin) per dendritic length in comparison to the distilled water group (p < 0.05). The low dose group only showed a reduction in the number of glial cells. However, simultaneous treatment of rats with taurine plus Allura Red prevented the above-mentioned changes. The acceptable daily dose of Allura Red could bring about impairment in spatial learning and memory as well as in the number of glial cells. On the other hand, the high dose of Allura Red could impair learning, memory, and mPFC structure. Thus, taurine could act as a neuroprotectant.

Modulatory effects of taurine on metabolic and oxidative stress parameters in a mice model of muscle overuse

OBJECTIVE

The aim of this study was to investigate the regulatory effects of taurine on the biochemical parameters of muscle injury by overuse.

METHODS

Male Swiss mice were divided into four groups: control (Ctrl), overuse (Ov), taurine (Tau), and overuse plus taurine (OvTau). High-intensity exercise sessions were administered for 21 d with concomitant subcutaneous injections of taurine (150 mg/kg). The mice were then sacrificed. The quadriceps muscles were surgically removed for subsequent histologic analysis and evaluation of mitochondrial function, oxidative stress parameters, tissue repair, and DNA damage markers.

RESULTS

The Ov group showed significant differences compared with the Ctrl group (all P <0.05). The fiber area decreased by 49.34%, whereas the centralized nuclei contents (Ctrl = 1.33%; Ov = 28.67%), membrane potential (Ctrl_suc = 179.05 arbitrary fluorescence units (AFUs), Ctrl_suc+ADP = 198.11 AFUs; Ov_suc = 482.95 AFUs, Ov_suc+ADP = 461.6 AFUs), complex I activity (Ctrl = 20.45 nmol ⋅ min ⋅ mg protein, Ov = 45.25 nmol ⋅ min ⋅ mg protein), hydrogen peroxide (Ctrl_suc = 1.08 relative fluorescence unit (RFU) ⋅ sec ⋅ mg protein, Ctrl_suc+ADP = 0.23 RFU ⋅ sec ⋅ mg protein; Ov_suc = 5.02 RFU ⋅ sec ⋅ mg protein, Ov_suc+ADP = 0.26 RFU ⋅ sec ⋅ mg protein) and malondialdehyde (Ctrl = 0.03 nmol ⋅ mg ⋅ protein, Ov = 0.06 nmol ⋅ mg ⋅ protein) levels, and DNA damage (Ctrl_freq = 7.17%, Ov_freq = 31.17%; Ctrl_index = 4.17, Ov_index = 72.5) were increased. Taurine administration reduced the number of centralized nuclei (OvTau = 5%), hydrogen peroxide levels (OvTau_suc = 2.81 RFU ⋅ sec ⋅ mg protein, OvTaus_suc+ADP = 1.54 RFU ⋅ sec ⋅ mg protein), membrane potential (OvTau_suc = 220.18 AFUs, OvTaus_suc+ADP = 235.28 AFUs), lipid peroxidation (OvTau = 0.02 nmol/mg protein), and DNA damage (OvTau_freq = 21.33%, OvTau_index = 47.83) and increased the fiber area by 54% (all P <0.05).

CONCLUSION

Taken together, these data suggest that taurine supplementation modulates various cellular remodeling parameters after overuse-induced muscle damage, and that these positive effects may be related to its antioxidant capacity.

Taurine supplementation reduces neuroinflammation and protects against white matter injury after intracerebral hemorrhage in rats

Intracerebral hemorrhage (ICH) initiates a neuroinflammatory cascade that contributes to substantial neuronal damage and neurological deterioration. Taurine, an abundant amino acid in the nervous system, is reported to reduce inflammatory injury in various central nervous system diseases, but its role and the possible underlying mechanisms in the pathology following ICH remains unclear. This study was designed to evaluate the effect of taurine supplementation on neurological deficits, acute inflammatory responses and white matter injury in a model of ICH in rats. Adult male Sprague-Dawley (SD) rats subjected to collagenase-induced ICH injury were injected intravenously with different concentrations of taurine or vehicle 10 min after ICH and subsequently daily for 3 days. Behavioral studies, brain water content, and assessments of hemorrhagic lesion volume were quantified at day 1 and day 3 post-ICH. Neuronal damage, peri-hematomal inflammatory responses, and white matter injury were determined at 24 h, meanwhile, the content of hydrogen sulfide (H₂S) along with the expression of cystathionine-β-synthase (CBS) and P2X7 receptor (P2X7R) in peri-hematomal tissues was analyzed to investigate the possible anti-inflammatory mechanism of taurine. Treatment with a high dosage of taurine (50 mg/kg) significantly attenuated functional deficits and reduced brain edema and hemorrhagic lesion volume after ICH. Taurine administration also resulted in significant amelioration of neuronal damage and white matter injury. These changes were associated with marked reductions in neutrophil infiltration, glial activation, and expression levels of inflammatory mediators. Moreover, the anti-inflammatory effect of taurine was accompanied by increased H₂S content, enhanced CBS expression, and less expression of P2X7R. Our study demonstrated that the high dosage of taurine supplementation effectively mitigated the severity of pathological inflammation and white matter injury after ICH, and the mechanism may be related to upregulation of H₂S content and reduced P2X7R expression.

Potential Benefits of Ameliorating Metabolic and Nutritional Abnormalities in People With Profound Developmental Disabilities

Background:

People with profound developmental disabilities have some of the most severe neurological impairments seen in society, have accelerated mortality due to huge medical challenges, and yet are often excluded from scientific studies. They actually have at least 2 layers of conditions: (1) the original disability and (2) multiple under-recognized and underexplored metabolic and nutritional imbalances involving minerals (calcium, zinc, and selenium), amino acids (taurine, tryptophan), fatty acids (linoleic acid, docosahexaenoic acid, arachidonic acid, adrenic acid, Mead acid, plasmalogens), carnitine, hormones (insulinlike growth factor 1), measures of oxidative stress, and likely other substances and systems.

Summary:

This review provides the first list of metabolic and nutritional abnormalities commonly found in people with profound developmental disabilities and, based on the quality of life effects of similar abnormalities in neurotypical people, indicates the potential effects of these abnormalities in this population which often cannot communicate symptoms.

Key messages:

We propose that improved understanding and management of these disturbed mechanisms would enhance the quality of life of people with profound developmental disabilities. Such insights may also apply to people with other conditions associated with disability, including some diseases requiring stem cell implantation and living in microgravity.

Protective effects of taurine in traumatic brain injury via mitochondria and cerebral blood flow

In mammalian tissues, taurine is an important natural component and the most abundant free amino acid in the heart, retina, skeletal muscle, brain, and leukocytes. This study is to examine the taurine's protective effects on neuronal ultrastructure, the function of the mitochondrial respiratory chain complex, and on cerebral blood flow (CBF). The model of traumatic brain injury (TBI) was made for SD rats by a fluid percussion device, with taurine (200 mg/kg) administered by tail intravenous injection once daily for 7 days after TBI. It was found that CBF was improved for both left and right brain at 30 min and 7 days post-injury by taurine. Reaction time was prolonged relative to the TBI-only group. Neuronal damage was prevented by 7 days taurine. Mitochondrial electron transport chain complexes I and II showed greater activity with the taurine group. The improvement by taurine of CBF may alleviate edema and elevation in intracranial pressure. Importantly taurine improved the hypercoagulable state.

Neuroprotective effect of allicin in a rat model of acute spinal cord injury

AIMS

This study aims to investigate the effect of allicin on motor functions and histopathologic changes after spinal cord injury and the mechanism underlying its neuroprotective effects.

MAIN METHODS

The motor function of rats was evaluated with the Basso, Beattie, and Bresna test. Histopathologic changes were evaluated by hematoxylin and eosin and Nissl staining. Spinal cord oxidative stress markers were determined by measuring glutathione and malondialdehyde content and superoxide dismutase activity using commercial kits. Inflammatory factors were determined by measuring tumor necrosis factor-α, interleukin-1β and interleukin-6 using ELISA assay. Apoptosis was examined using TUNEL staining. The effect of allicin on Nrf2 protein levels and localization was assessed using immunofluorescence staining and Western blotting analysis.

KEY FINDINGS

Results demonstrated that allicin accelerated the motor functional recovery and protected neuron damage against spinal cord injury (SCI). SCI-induced oxidative stress, inflammatory response and cell apoptosis in the spinal cord were also prevented by allicin. In addition, we observed that SCI increased Nrf2 nuclear expression, and allicin treatment further increased Nrf2 nuclear translocation in neurons and astrocytes. siRNA-mediated Nrf2 gene knockdown completely blocked the effect of allicin on spinal cord tissue.

SIGNIFICANCE

Our finding suggests that allicin promotes the recovery of motor function after SCI in rats, and this effect may be related to its anti-oxidant, anti-inflammatory and anti-apoptotic effects. Allicin mediated Nrf2 nuclear translocation may be involved in the protective effect as well.

Phase IV prospective clinical study to evaluate the effect of taurine on liver function in postsurgical adult patients requiring parenteral nutrition

BACKGROUND

Taurine's role in bile acid metabolism and anti-inflammatory activity could exert a protective effect on hepatobiliary complications associated with parenteral nutrition (PN). In this study, the effects of 2 amino acid solutions, with and without taurine, on liver function administered to nonacutely ill postsurgical patients as part of a short-term PN regimen were prospectively compared.

METHODS

Adult patients randomly received (double-blind) Tauramin 10% or a standard PN solution without taurine as the control (1.5 g amino acid/kg body weight [bw]/d; infusion rate of ≤4 mg glucose/kg bw/d) for a period of 5-30 days. γ-Glutamyl transpeptidase (GGT) and other indicators of liver function, glucose metabolism, lipid profile, inflammation markers, and treatment safety data were collected.

RESULTS

Thirty-five patients receiving taurine PN and 39 receiving control PN were enrolled (intention-to-treat [ITT] population). Most patients (n = 62) discontinued after day 7 of follow-up (per-protocol [PP] population: n = 24 and n = 27, respectively). ITT patients with high GGT values after 5 days of PN comprised 68.6% and 64.1%, respectively. The mean change in GGT values with respect to the baseline values was 167 ± 192 and 157 ± 185 IU/L, respectively. Low-density lipoprotein (LDL) cholesterol levels after 7 days of PN were significantly decreased in the taurine PN group of PP patients (-2.83 ± 30.9 vs 23.9 ± 27.0 mg/dL for control PN; P < .05). None of the adverse events reported (taurine PN: n = 6; control PN: n = 7) were treatment related.

CONCLUSION

PN solutions with and without taurine had similar effects on liver function parameters, except for an LDL reduction in PN with taurine, when administered to nonacutely ill postsurgical patients in the short term (5-7 days).

Taurine improves functional and histological outcomes and reduces inflammation in traumatic brain injury

We investigated the effect of taurine on inflammatory cytokine expression, on astrocyte activity and cerebral edema and functional outcomes, following traumatic brain injury (TBI) in rats. 72 rats were randomly divided into sham, TBI and Taurine groups. Rats subjected to moderate lateral fluid percussion injury were injected intravenously with taurine (200mg/kg) or saline immediately after injury or daily for 7days. Functional outcome was evaluated using Modified Neurological Severity Score (mNSS). Glial fibrillary acidic protein (GFAP) of the brain was measured using immunofluorescence. Concentration of 23 cytokines and chemokines in the injured cortex at 1 and 7days after TBI was assessed by Luminex xMAP technology. The results showed that taurine significantly improved functional recovery except 1day, reduced accumulation of GFAP and water content in the penumbral region at 7days after TBI. Compared with the TBI group, taurine significantly suppressed growth-related oncogene (GRO/KC) and interleukin (IL)-1β levels while elevating the levels of regulated on activation, normal T cell expressed and secreted (RANTES) at 1day. And taurine markedly decreased the level of 17 cytokine: eotaxin, Granulocyte colony-stimulating factor (G-CSF), Granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon-gamma (IFN-γ), IL-1α, IL-1β, IL-4, IL-5, IL-6, IL-10, IL-12p70, IL-13, IL-17, leptin, monocyte chemotactic protein-1 (MCP-1), tumor necrosis factor-alpha (TNF-α), vascular endothelial growth factor (VEGF), and only increased the level of MIP-1α in a week. The results suggest that taurine effectively mitigates the severity of brain damage in TBI by attenuating the increase of astrocyte activity and edema as well as pro-inflammatory cytokines.

Anti-interleukin-6 receptor antibody reduces neuropathic pain following spinal cord injury in mice

The present study reports the beneficial effects of an anti-mouse interleukin-6 (IL-6) receptor antibody (MR16-1) on neuropathic pain in mice with spinal cord injury (SCI). Following laminectomy, contusion SCI models were produced using an Infinite Horizon (IH)-impactor. MR16-1 was continuously injected for 14 days using Alzet osmotic pumps. A mouse IL-6 ELISA kit was then used to analyze IL-6 levels in the spinal cord tissue between 12 and 72 h after injury. Motor and sensory functions were evaluated each week using the Basso Mouse Scale (BMS), plantar von Frey and thermal threshold tests. Histological examinations were performed 42 days after SCI. Between 24 and 72 h after SCI, the expression levels of IL-6 were significantly decreased in the MR16-1 treated group. Six weeks after surgery, the BMS score of the MR16-1-treated group indicated significant recovery of neurological functions. MR16-1-treated mice in the SCI group exhibited lower paw withdrawal thresholds in the plantar von Frey and thermal tests, which were used to evaluate allodynia. MR16-1 treatment significantly increased the area of Luxol fast blue-stained tissue, representing spared myelin sheaths. These results indicate that the continuous inhibition of IL-6 signaling by MR16-1 between the early and sub-acute phases following SCI leads to neurological recovery and the suppression of hyperalgesia and allodynia. Overall, our data suggest that the inhibition of severe inflammation may be a promising neuroprotective approach to limit secondary injury following SCI and that an anti-IL-6 receptor antibody may have clinical potential for the treatment of SCI.

Novel nutritional substrates in surgery

Pharmaco-nutrients have beneficial effects on protective and immunological mechanisms in patients undergoing surgery, which are important for recovery after injury and in combating infectious agents. The aim of this review article was to outline the potential of the administration of nutritional substrates to surgical patients and the underlying mechanisms that make them particularly important in peri-operative care. Surgery causes a stress response, which has catabolic effects on the body's substrate stores. The amino acid glutamine is a stimulating agent for immune cells. It activates protective mechanisms through its role as a precursor for antioxidants and it improves the barrier function of the gut. Arginine also enhances the function of the immune system, since it is the substrate for T-lymphocytes. Furthermore, n-3 PUFA stabilise surgery-induced hyper-inflammation. Taurine is another substrate that may counteract the negative effects of surgical injury on acid–base balance and osmotic balance. These pharmaco-nutrients rapidly become deficient under the influence of surgical stress. Supplementation of these nutrients in surgical patients may restore their protective and immune-enhancing actions and improve clinical outcome. Moreover, pre-operative fasting is still common practice in the Western world, although fasting has a negative effect on the patient's condition and the recovery after surgery. This may be counteracted by a simple intervention such as administering a carbohydrate-rich supplement just before surgery. In conclusion, there are various nutritional substrates that may be of great value in improving the condition of the surgical patient, which may be beneficial for post-operative recovery.

Heteroarylketones inhibit astroglial interleukin-6 expression via a STAT3/NF-κB signaling pathway

Background

Elevated brain levels of the pleiotropic cytokine interleukin-6, which is mainly secreted from activated local astrocytes, contribute to pathological events including neuroinflammation and neurodegeneration. Thus, inhibition of pathological IL-6 expression provides a rationale strategy for targeting the onset or further progression of neurological disorders including Alzheimer's disease, multiple sclerosis, Parkinson's disease and traumatic brain injury. The purpose of this study was to identify and to characterize new potent inhibitors of astrocytic IL-6 expression for further therapeutic development of novel anti-inflammatory and neuroprotective drugs.

Methods

Oncostatin M (OSM)-treated human glioma U343 cells were used as model for induction of astrocytic IL-6 expression. This model was characterized by immunoblotting, siRNA technique, ELISA and qRT-PCR and used to screen low molecular weight compound libraries for IL-6-lowering effects. To validate bioactive compounds identified from library screens, bacterial lipopolysaccharide was used to induce IL-6 expression in cultivated primary astrocytes and in mice in vivo. To dissect underlying molecular mechanisms, protein extracts from OSM-treated U343 cells were analyzed by phospho-specific immunoblotting and immunocytochemistry as well as by co-immunoprecipitation.

Results

OSM-treatment (100 ng/ml; 24 h) led to 30-fold increase of IL-6 secretion from U343 cells. The temporal profile of IL-6 mRNA induction displayed a biphasic induction pattern with peak synthesis at 1 h (6.5-fold) and 16 h (5.5-fold) post stimulation. IL-6 protein release did not show that biphasic pattern and was detected as early as 3 h post stimulation reaching a maximum at 24 h. The screen of compound libraries identified a set of heteroarylketones (HAKs) as potent inhibitors of IL-6 secretion. HAK compounds affected the second peak in IL-6 mRNA synthesis, whereas the first peak was insensitive to HAK treatment. HAK compounds also suppressed lipopolysaccharide-induced IL-6 expression in primary murine astrocytes as well as in brain and plasma samples from lipopolysaccharide-treated mice. Finally, HAK compounds were demonstrated to specifically suppress the OSM-induced phosphorylation of STAT3 at serine 727 and the physical interaction of pSTAT3^S727 with p65.

Conclusion

Heteroarylketone compounds are potent inhibitors of IL-6 expression in vitro and in vivo and may represent a new class of potent anti-inflammatory and neuroprotective drugs.