Taurine: A Source And Application For The Relief Of Visual Fatigue Part 2
Sep 27, 2023
3.2.1. Reducing Retinal Stress Damage: Oxidation, Inflammation, Apoptosis
The main cause of visual fatigue is the eye's continuous work or the eye or the exposure of the eye to strong light and oxygen. This situation promotes enhanced ocular metabolism followed by an increase in peroxides and, therefore, vulnerability to oxidative damage, which begins to occur [78]. Current studies have shown that one of the most essential protective effects of taurine on cells is its antioxidant effect, mediated by three different processes: First, taurine neutralizes the neutrophil oxidant hypochlorous acid, and the resulting reaction product, chloramine taurate, is also better at hindering the onset of inflammation [79,80]. Second, taurine reduces superoxide production by mitochondrial metabolism [81,82]. Third, ROS produced by cellular metabolism or external environmental stimuli tends to attack antioxidant enzymes, leading to increased oxidative damage [82,83], whereas taurine can effectively protect these antioxidant enzymes from ROS attack, thus counteracting oxidative stress [33,84]. It is well known that light exposure tends to lead to retinal stress damage and damage or loss of photoreceptors and dietary taurine supplementation can increase the concentration of taurine in the retina that is reduced by light exposure, reduce light exposure-induced retinal MDA overproduction and increase retinal superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity in the retina.
Cistanche can act as an anti-fatigue and stamina enhancer, and experimental studies have shown that the decoction of Cistanche tubulosa could effectively protect the liver hepatocytes and endothelial cells damaged in weight-bearing swimming mice, upregulate the expression of NOS3, and promote hepatic glycogen synthesis, thus exerting anti-fatigue efficacy. Phenylethanoid glycoside-rich Cistanche tubulosa extract could significantly reduce the serum creatine kinase, lactate dehydrogenase, and lactate levels, and increase the hemoglobin (HB) and glucose levels in ICR mice, and this could play an anti-fatigue role by decreasing the muscle damage and delaying the lactic acid enrichment for energy storage in mice. Compound Cistanche Tubulosa Tablets significantly prolonged the weight-bearing swimming time, increased the hepatic glycogen reserve, and decreased the serum urea level after exercise in mice, showing its anti-fatigue effect. The decoction of Cistanchis can improve endurance and accelerate the elimination of fatigue in exercising mice, and can also reduce the elevation of serum creatine kinase after load exercise and keep the ultrastructure of skeletal muscle of mice normal after exercise, which indicates that it has the effects of enhancing physical strength and anti-fatigue. Cistanchis also significantly prolonged the survival time of nitrite-poisoned mice and enhanced the tolerance against hypoxia and fatigue.
Click on fatigue causes
【For more info:george.deng@wecistanche.com / WhatsApp:8613632399501】
At the same time, taurine also inhibited caspase-1 expression in the apoptotic signaling pathway of photoreceptor cells, suggesting that dietary taurine may reduce photochemical stress-induced retinal damage by mediating retinal antioxidant and anti-apoptotic mechanisms, which also suggests that taurine has an indispensable and important physiological role in the structural and functional development of the retina [85]. In a study by Diego et al. [86], it was again confirmed that taurine is an essential nutrient for the maintenance of regular physiological activity of retinal cells, especially in the presence of light-induced photoreceptor damage, and that the retina has a higher requirement for taurine. Moreover, taurine significantly improved taurine levels and photoreceptor survival in retinal dystrophy rats reduced the release of pro-inflammatory factors and oxidative stress damage in the retina, and effectively repaired and reduced RPE cell damage [87]. This suggests that taurine may reduce damage to retinal function through anti-inflammatory and antioxidant pathways [88]. In addition, taurine can also prevent retinal and optic nerve morphological changes by reducing the retinal oxidative stress pathway and inhibiting Endothelin-1 (a potent vasoconstrictor involved in glaucomatous retinal vascular dysregulation and oxidative stress)-induced retinal cell apoptosis [89].
Studies have shown that the visual function of the eye declines with age. Retinal damage in some animal models of aging may also be closely related to taurine deficiency [90]. Wang et al. used targeted metabolomics to analyze and compare the metabolites in the eyes of 6-week-old C57 BL6/J young mice with those of 73-week-old aged mice. The results of the assay showed that senescent mice had reduced electroretinogram responses and a reduced number of photoreceptors compared to young mice, and impaired taurine metabolism was observed [91]. In vivo and ex vivo experimental studies have shown that taurine ameliorates AMD damage by reducing the retinal apoptotic pathway [92].
The above studies have shown that taurine has a vital role in maintaining normal visual and photoreceptor functions. Taurine can effectively improve stress damage, especially oxidative stress damage, arising in the retina. In addition, taurine can also play a role in protecting retinal function from stress damage through anti-inflammatory and anti-apoptotic effects, thus relieving visual fatigue.
3.2.2. Reducing Retinal Excitotoxic Damage and Providing Neuroprotection
The bipolar cells, photoreceptors, and ganglion cells of the eye contain high concentrations of glutamate, an important neurotransmitter, which, when overloaded, triggers excitotoxicity and apoptotic signaling, leading to retinal dysfunction [93]. Furthermore, retinal excitotoxic damage is also the basis for loss of visual function [94,95]. This retinal excitotoxic damage also includes overstimulation of glutamate receptors, especially the N-methyl-D-aspartic acid (NMDA) subtype of glutamate receptors, which causes calcium inward flow and disrupts intracellular environmental homeostasis, triggering pro-apoptotic pathways [96]. Therefore, induction of retinal damage in rats by intravitreal injection of NMDA has been used as a representative animal model of excitotoxic retinal damage [97]. In contrast, taurine has been shown to provide neuroprotection through a pathway that reduces intracellular free calcium, thereby exerting resistance to glutamate-induced excitotoxicity [98]. Also, taurine is a potential neuromodulator of glutamate transmission [99]. Taurine can effectively inhibit glutamate-induced excitotoxicity and protect retinal function from damage through long-term dietary supplementation of the taurine pathway [100]. In addition, experimental data show that taurine is effective in scavenging a wide range of reactive oxygen and nitrogen species at different physiological concentrations [101]. Therefore, the reducing effect of dietary taurine on retinal oxidative stress may not only be due to its ability to restore and strengthen the retinal antioxidant defense but also due to taurine’s ability to enhance free radical bursting and thus prevent NMDA-induced retinal damage by reducing retinal oxidative stress [102].
The Royal College of Surgeons (RCS) rat is a commonly used animal model for retinitis pigmentosa. The main manifestations of this rat are impaired phagocytosis of RPE cells [103–106] with progressive photoreceptor degeneration [107–110], increased retinal glial cell proliferation, altered retrograde axonal transport of retinal ganglion cells (RGC) and loss of RGC [111–113]. One study claimed that the first sign of retinal degeneration in RCS rats was a significant decrease in taurine levels. Data show that retinal taurine is supplied by RPE cells and Müller cells [91,114]. At the same time, taurine depletion also increases retinal glial cell proliferation and impairs the phagocytosis of RPE cells [35]. This suggests that taurine is indispensable for maintaining normal RPE function and that ameliorating the detrimental damage to RPE cells by taurine supplementation may be a potential dietary intervention strategy. Indeed, the addition of 0.2 M taurine to the drinking water of RCS rats revealed a significant reduction in the number of microglia in the outer retinal layer, an effective reduction in glial fibrillary acidic protein (GFAP) content in Müller cells, a significant reduction in oxidative stress in the outer and inner retinal nuclei and also improved maintenance of retinal synaptic connections. This suggests that dietary taurine may act to improve photoreceptor damage and increase retinal electrical responses by mediating various neuroprotective mechanisms [88].
In addition, taurine may also play a role in improving retinal damage by improving retinal synaptic connections, maintaining the balance of the Bcl-2/Bax ratio (which determines apoptosis), and reducing reactive glial proliferation in retinal Müller cells [115]. In conclusion, the above studies suggest that taurine may play a role in improving the normal function and morphology of the damaged RPE, RGC, and photoreceptors by reducing excitotoxicity in the retina as well as a variety of neuroprotective mechanisms, thereby alleviating visual fatigue.
The health effects of taurine on the retina and its necessity are detailed in Table 3.
4. Conclusions
Visual fatigue is mainly caused by a decline or impairment of retinal function, especially when prolonged eye use leads to an excessive accumulation of metabolic waste in the eye that cannot be cleared, causing various stress injuries. Taurine is considered an essential nutrient for the function and survival of retinal photoreceptors, RGCs, and RPE cells [36,87,116], and its depletion increases the susceptibility of the retina to light exposure damage [35,36] and also increases glial cell proliferation and oxidative stress in the retina, impairing the normal phagocytic capacity of the RPE [35]. In addition, numerous clinical [117,118] and animal studies [33,119,120] have shown that taurine depletion can induce impaired retinal function and even pathological eye disease. Taurine supplementation is effective in improving retinal photoreceptor degeneration [88,121] and retinal and optic nerve damage [33,90]. However, the current research on the protective effect of taurine on the retina is mainly focused on its antioxidant effect, Research on non-antioxidant pathways to improve retinal damage may be an important direction for future research. In addition, taurine, as a natural amino acid, has a high safety profile and is allowed to be added to functional drinks and other food products in many countries. Due to the important protective role of taurine in the retina and its high food safety, its application in the development of functional foods for the relief of visual fatigue is very promising. Therefore, in the future development of functional foods for the relief of visual fatigue, research on the synergistic effect of taurine in combination with other functional ingredients can be enhanced to clarify the optimal formulation ratio between taurine and other functional ingredients, to maximize the visual fatigue relief function of the products.
A rational selection and extraction study of raw materials is one of the necessary and effective means to maximize their function in formulation. Therefore, this paper systematically reviews the endogenous synthesis pathways and exogenous dietary distribution of taurine in the human body, as well as its extraction and industrial production. Both chemical synthesis and bio-fermentation methods are suitable for the industrial production of taurine of high purity, but each has certain disadvantages. Extraction methods, on the other hand, are not suitable for the industrial production of higher-purity taurine but are of great importance for the development of functional food ingredients. This is because the body obtains taurine through exogenous means by consuming a certain dose of taurine-rich food, which is then digested, absorbed, and metabolized by the body to truly replenish the body with the required amount of taurine. This process emphasizes not only the level of taurine content in food but also the relationship between dose and efficacy. The selection of suitable raw materials and extraction methods can effectively increase the content of taurine in raw materials and reduce the dosage of the raw materials themselves, which improves the utilization of raw materials, enriches the range of raw materials available for the formulation of functional foods for the relief of visual fatigue, improves the novelty of product formulations and also facilitates researchers to diversify the design of functional food dosage forms according to the characteristics of the population. It is also very suitable for the research and development of new food ingredients as well as functional food ingredients.
In conclusion, taurine has an important protective effect on retinal function, mainly due to its antioxidant and neuroprotective effects, and is essential for the function and survival of retinal photoreceptors, RGC, and RPE cells. However, as the amount of taurine synthesized by the human body is not sufficient to meet the health needs of the body, it needs to be obtained through dietary supplementation. This suggests the importance and necessity of dietary taurine supplementation in promoting ocular health. This paper, therefore, provides a systematic review of the sources of taurine, including the endogenous metabolic and exogenous dietary routes, as well as a detailed review of the distribution and production of exogenous taurine. The physiological mechanisms underlying the production of visual fatigue are summarized and the research progress of taurine in relieving visual fatigue is reviewed, including the safety of consumption and the mechanism of action in relieving visual fatigue, to provide some reference and inspiration for the development and application of taurine in functional foods for relieving visual fatigue.
Author Contributions: Conceptualization, H.D.; methodology, H.D.; software, J.G.; validation, W.S.; formal analysis, H.D.; investigation, H.D.; resources, W.S.; data curation, J.G.; writing—original draft preparation, H.D. and W.S.; writing—review and editing, W.Y.; visualization, H.D.; supervision, W.Y.; project administration, W.Y.; funding acquisition, W.Y. All authors have read and agreed to the published version of the manuscript.
Funding: This research was funded by the National Natural Science Foundation of China, grant number 32172244, and the Academic Research Projects of Beijing Union University, grant numbers XP202006 and ZK70202004.
Institutional Review Board Statement: Not applicable.
Informed Consent Statement: Not applicable.
Data Availability Statement: Not applicable.
Acknowledgments: The authors would like to thank Wenjie Yan for his guidance and financial help.
Conflicts of Interest: The authors declare no conflict of interest.
References
1. Le, Z.; Antonov, E.; Mao, Q.; Petrov, V.; Wang, Y.; Wang, W.; Shevkolenko, M.; Dong, W. Anti-Fatigue Glasses Based on Microprisms for Preventing Eyestrain. Sensors 2022, 22, 1933. [CrossRef] [PubMed]
2. Zheng, F.; Hou, F.; Chen, R.; Mei, J.; Huang, P.; Chen, B.; Wang, Y. Investigation of the Relationship Between Subjective Symptoms of Visual Fatigue and Visual Functions. Front. Neurosci. 2021, 15, 686740. [CrossRef] [PubMed]
3. Vilela, M.A.; Pellanda, L.C.; Fassa, A.G.; Castagno, V.D. “Prevalence of asthenopia in children: A systematic review with meta-analysis. J. Pediatr. 2015, 91, 320–325. [CrossRef] [PubMed]
4. Toda, I.; Fujishima, H.; Tsubota, K. Ocular fatigue is the major symptom of dry eye. Acta Ophthalmol. 1993, 71, 347–352. [CrossRef] [PubMed]
5. Sheppard, A.L.; Wolffsohn, J.S. Digital eye strain: Prevalence, measurement and amelioration. BMJ Open Ophthalmol. 2018, 3, e000146. [CrossRef]
6. Abdi, S.; Rydberg, A. Asthenopia in Schoolchildren, Orthoptic and Ophthalmological Findings and Treatment. Doc. Ophthalmol. 2005, 111, 65–72. [CrossRef]
7. Portello, J.K.; Rosenfield, M.; Bababekova, Y.; Estrada, J.M.; Leon, A. Computer-related visual symptoms in office workers. Ophthalmic Physiol. Opt. 2012, 32, 375–382. [CrossRef]
8. Reddy, S.C.; Low, C.K.; Lim, Y.P.; Low, L.L.; Mardina, F.; Nursaleha, M.P. Computer vision syndrome: A study of knowledge and practices in university students. Nepal. J. Ophthalmol. 2013, 5, 161–168. [CrossRef]
9. Fan, B.; Zhang, C.; Chi, J.; Liang, Y.; Bao, X.; Cong, Y.; Yu, B.; Li, X.; Li, G.-Y. The Molecular Mechanism of Retina Light Injury Focusing on Damage from Short Wavelength Light. Oxidative Med. Cell Longev. 2022, 2022, 8482149. [CrossRef]
10. Ayaki, M.; Kuze, M.; Kondo, M.; Tsubota, K.; Negishi, K. Association between Retinal Nerve Fiber Layer Thickness and Eye Fatigue. BioMed Res. Int. 2019, 2019, 3014567-8. [CrossRef]
11. Yang, S.; Zhou, J.; Li, D. Functions and Diseases of the Retinal Pigment Epithelium. Front. Pharmacol. 2021, 12, 727870. [CrossRef] [PubMed]
12. Upadhyay, M.; Milliner, C.; Bell, B.A.; Bonilha, V.L. Oxidative stress in the retina and retinal pigment epithelium (RPE): Role of aging, and DJ-1. Redox Biol. 2020, 37, 101623. [CrossRef] [PubMed]
13. Subramaniam, M.D.; Iyer, M.; Nair, A.P.; Venkatesan, D.; Mathavan, S.; Eruppakotte, N.; Kizhakkillach, S.; Chandran, M.K.; Roy, A.; Gopalakrishnan, A.V.; et al. Oxidative stress and mitochondrial transfer: A new dimension towards ocular diseases. Genes Dis. 2022, 9, 610–637. [CrossRef] [PubMed]
14. Ruiz-Pastor, M.J.; Kutsyr, O.; Lax, P.; Cuenca, N. Decrease in DHA and other fatty acids correlates with photoreceptor degeneration in retinitis pigmentosa. Exp. Eye Res. 2021, 209, 108667. [CrossRef]
15. Suzumura, A.; Terao, R.; Kaneko, H. Protective Effects and Molecular Signaling of n-3 Fatty Acids on Oxidative Stress and Inflammation in Retinal Diseases. Antioxidants 2020, 9, 920. [CrossRef]
16. Kim, M.J.; Kim, D.H.; Kwak, H.S.; Yu, I.-S.; Um, M.Y. Protective Effect of Chrysanthemum boreale Flower Extracts against A2E-Induced Retinal Damage in ARPE-19 Cell. Antioxidants 2022, 11, 669. [CrossRef]
17. Di Pierdomenico, J.; García-Ayuso, D.; Pinilla, I.; Cuenca, N.; Vidal-Sanz, M.; Agudo-Barriuso, M.; Villegas-Pérez, M.P. Early Events in Retinal Degeneration Caused by Rhodopsin Mutation or Pigment Epithelium Malfunction: Differences and Similarities. Front. Neuroanat. 2017, 11, 14. [CrossRef]
18. Cuenca, N.; Fernández-Sánchez, L.; Campello, L.; Maneu, V.; De la Villa, P.; Lax, P.; Pinilla, I. Cellular responses following retinal injuries and therapeutic approaches for neurodegenerative diseases. Prog. Retin. Eye Res. 2014, 43, 17–75. [CrossRef]
19. de Hoz, R.; Rojas, B.; Ramírez, A.I.; Salazar, J.J.; Gallego, B.I.; Triviño, A.; Ramírez, J.M. Retinal Macroglial Responses in Health and Disease. BioMed Res. Int. 2016, 2016, 2954721. [CrossRef]
20. Liu, B.; Hunter, D.J.; Smith, A.A.; Chen, S.; Helms, J.A. The capacity of neural crest-derived stem cells for ocular repair. Birth Defects Res. Part C Embryo Today Rev. 2014, 102, 299–308. [CrossRef]
21. Peng, L.; Parpura, V.; Verkhratsky, A. EDITORIAL Neuroglia as a Central Element of Neurological Diseases: An Underappreciated Target for Therapeutic Intervention. Curr. Neuropharmacol. 2014, 12, 303–307. [CrossRef] [PubMed]
22. Zhang, X.; Cheng, M.; Chintala, S.K. Kainic Acid–Mediated Upregulation of Matrix Metalloproteinase-9 Promotes Retinal Degeneration. Investig. Ophthalmol. Vis. Sci. 2004, 45, 2374–2383. [CrossRef] [PubMed]
23. Roche, S.L.; Ruiz-Lopez, A.M.; Moloney, J.N.; Byrne, A.M.; Cotter, T.G. Microglial-induced Müller cell gliosis is attenuated by progesterone in a mouse model of retinitis pigmentosa. Glia 2018, 66, 295–310. [CrossRef] [PubMed]
24. Di Pierdomenico, J.; Garcia-Ayuso, D.; Agudo-Barriuso, M.; Vidal-Sanz, M.; Villegas-Perez, M.P. Role of microglial cells in photoreceptor degeneration. Neural Regen. Res. 2019, 14, 1186–1190. [CrossRef]
25. Kalloniatis, M.; Napper, G.A. Retinal neurochemical changes following application of glutamate as a metabolic substrate. Clin. Exp. Optom. 2002, 85, 27–36. [CrossRef]
26. Barabas, P.; Kovacs, I.; Kardos, J.; Schousboe, A. Exogenous glutamate and taurine exert differential actions on light-induced release of two endogenous amino acids in isolated rat retina. J. Neurosci. Res. 2003, 73, 731–736. [CrossRef]
27. Payet, O.; Maurin, L.; Bonne, C.; Muller, A. Hypoxia stimulates glutamate uptake in whole rat retinal cells in vitro. Neurosci. Lett. 2004, 356, 148–150. [CrossRef]
28. Zhao, L.; Zabel, M.K.; Wang, X.; Ma, W.; Shah, P.; Fariss, R.N.; Qian, H.; Parkhurst, C.N.; Gan, W.B.; Wong, W.T. Microglial phagocytosis of living photoreceptors contributes to inherited retinal. EMBO Mol. Med. 2015, 7, 1179–1197. [CrossRef]
29. Chen, F.; Mi, M.; Zhang, Q.; Wei, N.; Chen, K.; Xu, H.; Yuan, J.; Zhou, Y.; Lang, H.; Yu, X.; et al. Taurine Buffers Glutamate Homeostasis in Retinal Cells in vitro under Hypoxic Conditions. Ophthalmic Res. 2010, 44, 105–112. [CrossRef]
30. Ripps, H.; Shen, W. Review: Taurine: A “very essential” amino acid. Mol. Vis. 2012, 18, 2673–2686.
31. Wójcik, O.P.; Koenig, K.L.; Zeleniuch-Jacquotte, A.; Costa, M.; Chen, Y. The potential protective effects of taurine on coronary heart disease. Atherosclerosis 2010, 208, 19–25. [CrossRef] [PubMed]
32. EFSA Panel on Additives and Products or Substances Used in Animal Feed (FEEDAP). Scientific Opinion on the safety and efficacy of taurine as a feed additive for all animal species. EFSA J. 2012, 10, 2736.
33. Froger, N.; Cadetti, L.; Lorach, H.; Martins, J.; Bemelmans, A.; Dubus, E.; Degardin, J.; Pain, D.; Forster, V.; Chicaud, L.; et al. Taurine Provides Neuroprotection against Retinal Ganglion Cell Degeneration. PLoS ONE 2012, 7, e42017. [CrossRef]
34. Hayes, K.C.; Care, R.; Schmidt, S.Y. Retinal degeneration associated with taurine deficiency in the cat. Science 1976, 188, 949–953. [CrossRef] [PubMed]
35. Martínez-Vacas, A.; Di Pierdomenico, J.; Valiente-Soriano, F.J.; Vidal-Sanz, M.; Picaud, S.; Villegas-Pérez, M.P.; García-Ayuso, D. Glial Cell Activation and Oxidative Stress in Retinal Degeneration Induced by β-Alanine Caused Taurine Depletion and Light Exposure. Int. J. Mol. Sci. 2021, 23, 346. [CrossRef] [PubMed]
36. Hadj-Saïd, W.; Froger, N.; Ivkovic, I.; Jiménez-López, M.; Dubus, É.; Dégardin-Chicaud, J.; Simonutti, M.; Quénol, C.; Neveux, N.; Villegas-Pérez, M.P.; et al. Quantitative and Topographical Analysis of the Losses of Cone Photoreceptors and Retinal Ganglion Cells Under Taurine Depletion. Investig. Ophthalmol. Vis. Sci. 2016, 57, 4692–4703. [CrossRef]
37. Zeng, K.; Xu, H.; Mi, M.; Zhang, Q.; Zhang, Y.; Chen, K.; Chen, F.; Zhu, J.; Yu, X. Dietary Taurine Supplementation Prevents Glial Alterations in Retina of Diabetic Rats. Neurochem. Res. 2009, 34, 244–254. [CrossRef]
38. Wu, D.; Song, L.; Zhu, C.; Zhang, X.; Guo, H.; Yang, C. Solubility of taurine and its application for the crystallization process improvement. J. Mol. Liq. 2017, 241, 326–333. [CrossRef]
39. Wang, L.W. Effect of taurine supplementation on athletic performance of sports athletes. Food Res. Dev. 2022, 43, 231–232.
40. Tevatia, R.; Allen, J.; Rudrappa, D.; White, D.; Clemente, T.E.; Cerutti, H.; Demirel, Y.; Blum, P. The taurine biosynthetic pathway of microalgae. Algal Res. 2015, 9, 21–26. [CrossRef]
41. Vitvitsky, V.; Garg, S.K.; Banerjee, R. Taurine Biosynthesis by Neurons and Astrocytes. J. Biol. Chem. 2011, 286, 32002–32010. [CrossRef] [PubMed]
42. Lund, E.K. Health benefits of seafood; Is it just the fatty acids? Food Chem. 2013, 140, 413–420. [CrossRef]
43. Wang, F. Extraction, Isolation, and Purification of Taurine from Zea mays. Master’s Thesis, Nanjing Agricultural University, Nanjing, China, 2014.
44. Xie, Z.; Yao, Y.; Liu, B.; Chen, X.; Fang, T. Research progress of taurine extraction and detection methods. Food Ind. Sci. Technol. 2019, 40, 323–331. [CrossRef]
45. Huang, X.; Hou, S.; Li, G.; Cai, D.K.; Su, Z. A review of taurine as an active ingredient in Chinese medicine. Chin. Folk. Remedies 2005, 9, 64–65. [CrossRef]
46. Uchida, M.; Kurushima, H.; Ishihara, K.; Murata, Y.; Toyota, K.; Ishida, N.; Niwa, K.; Araki, T. Characterization of fermented seaweed sauce prepared from nori (Pyropia yezoensis). J. Biosci. Bioeng. 2017, 123, 327–332. [CrossRef]
47. Lv, R.; Chen, R.; Chen, X.; Fang, T. Research progress on the extraction of natural taurine from abalone offal. Anhui Agric. Bull. 2019, 25, 14–16+83. [CrossRef]
48. Zhang, M.D.; Zan, N.; Li, S.R.; Zhou, Y.J. Research progress on the processing and detection technology of taurine and its application. Agric. Prod. Process. 2019, 19, 68–72+74. [CrossRef]
49. Wang, C.; Li, J.; Cao, Y.; Huang, J.; Lin, H.; Zhao, T.; Liu, L.; Shen, P.; McClements, D.J.; Chen, J.; et al. Extraction and characterization of pectic polysaccharides from Choerospondias axillaris peels: Comparison of hot water and ultrasound-assisted extraction methods. Food Chem. 2023, 401, 134156. [CrossRef]
50. Vinatoru, M. Ultrasonically assisted extraction (UAE) of natural products some guidelines for good practice and reporting. Ultrason. Sonochem. 2015, 25, 94–95. [CrossRef]
51. Martín-García, B.; Pasini, F.; Verardo, V.; Díaz-De-Cerio, E.; Tylewicz, U.; Gómez-Caravaca, A.M.; Caboni, M.F. Optimization of Sonotrode Ultrasonic-Assisted Extraction of Proanthocyanidins from Brewers' Spent Grains. Antioxidants 2019, 8, 282. [CrossRef]
52. Ji, L.; Liu, T.; Wang, Y.; Li, X.; Li, H.; Jiang, X.; Sun, Y. Study on the extraction process of taurine in kui clams. China Agric. Sci. Technol. Her. 2017, 19, 132–138. [CrossRef]
53. Jiang, X. Process study of taurine extraction from emerald mussel. Food Sci. Technol. 2006, 1, 62–64.
54. Qian, A.; Yan, S.; Yu, Y.; Lin, X. Exploration of pre-treatment methods for the determination of taurine in seafood. China Agron. Bull. 2006, 5, 94–97.
55. Qian, Q. Research progress on the extraction of active substances such as taurine, polysaccharides, and peptides from marine organisms. Food Ind. Sci. Technol. 2013, 34, 383–387. [CrossRef]
56. Ma, C.-C.; Butler, D.; Milligan, V.; Hammann, B.A.; Luo, H.; Brazdil, J.F.; Liu, D.; Chaudhari, R.V.; Subramaniam, B. Continuous Process for the Production of Taurine from Monoethanolamine. Ind. Eng. Chem. Res. 2020, 59, 13007–13015. [CrossRef]
57. Bulychev, E.Y.; Rubanyak, N.Y. Commercial Synthesis of 2-Aminoethanesulfonic Acid (Taurine). Pharm. Chem. J. 2013, 46, 740–741. [CrossRef]
58. Yeh, S.; Deng, J.; Liu, Q.-S.; Deng, B. Research progress of taurine nutrition and its application in cat food. Guangdong Anim. Husb. Vet. Sci. Technol. 2021, 46, 21–26+43.
59. Joo, Y.-C.; Ko, Y.J.; You, S.K.; Shin, S.K.; Hyeon, J.E.; Musaad, A.S.; Han, S.O. Creating a New Pathway in Corynebacterium glutamicum for the Production of Taurine as a Food Additive. J. Agric. Food Chem. 2018, 66, 13454–13463. [CrossRef]
60. Jenny. High-Voltage Pulsed Electric Field-Assisted Enzymatic Digestion of Mussel Meat for the Preparation of Taurine. Master’s Thesis, Jilin University, Changchun, China, 2020. [CrossRef]
61. Liu, X.; Huang, L.; Bai, Y.; Liu, X.; Li, S. Extracting bio-zinc and taurine from Pinctada martensii meat. J. Food Sci. 2020, 85, 1125–1131. [CrossRef]
62. Guo, Z.; Ge, X.; Han, L.; Yang, L.; Yu, Q. Ultrasound-assisted extraction and purification of taurine from bovine liver. J. Food Compos. Anal. 2020, 90. prepublish. [CrossRef]
63. Wang, F.; Guo, X.-Y.; Zhang, D.-N.; Wu, Y.; Wu, T.; Chen, Z.-G. Ultrasound-assisted extraction and purification of taurine from the red algae Porphyra yezoensis. Ultrason. Sonochem. 2015, 24, 36–42. [CrossRef] [PubMed]
64. Hu, K.-L.; Gao, R.-C.; Yang, F.-S.; Liu, W.-T.; Yang, J.-F. Study on the process of taurine preparation by enzymatic digestion of Philippine clam boiling liquid. J. Light Ind. 2018, 33, 26–33.
65. Liu, Y.; Zhang, Z.; Tong, H.; Sun, K.; Song, X. Optimization of enzymatic process conditions of oyster taurine extraction by neutral protease using response surface methodology. Food Sci. 2011, 32, 25–28.
66. Chen, J.; Ouyang, J.; Liu, Z.; Zhou, L.; Huang, H.; Ying, X. Research progress on the synthesis process and crystallization purification of taurine. Mod. Chem. 2021, 41, 57–62. [CrossRef]
67. Scientific Committee on Food (SCF). Opinion on Caffeine, T aurine and D-Glucurono-γ-Lactone as Constituents of So-Called “Energy” Drinks; SCF: Brussels, Belgium, 1999; pp. 1–12.
68. Sanz-Serrano, J.; Vettorazzi, A.; Muruzabal, D.; Azqueta, A.; de Cerain, A.L. In Vitro Genotoxicity Assessment of Functional Ingredients: Betaine, Choline, and Taurine. Foods 2021, 10, 339. [CrossRef]
69. Menzie, J.; Prentice, H.; Wu, J.-Y. Neuroprotective mechanisms of taurine against ischemic stroke. Brain Sci. 2013, 3, 877–907. [CrossRef]
70. Zhang, M.; Bi, L.F.; Fang, J.H.; Su, X.L.; Da, G.L.; Kuwamori, T.; Kagamimori, S. Beneficial effects of taurine on serum lipids in overweight or obese non-diabetic subjects. Amino Acids 2004, 26, 267–271. [CrossRef]
71. Murakami, S.; Kondo, Y.; Nagata, T. Effects of long-term treatment with taurine in mice fed a high-fat diet: Improvement in cholesterol metabolism and vascular lipid accumulation by taurine. Adv. Exp. Med. Biol. 2000, 483, 177–186.
72. Sturman, J.A.; Messing, J.M. High Dietary Taurine Effects on Feline Tissue Taurine Concentrations and Reproductive Performance. J. Nutr. 1992, 122, 82–88. [CrossRef]
73. Shao, A.; Hathcock, J.N. Risk assessment for the amino acids taurine, l-glutamine, and l-arginine. Regul. Toxicol. Pharmacol. 2008, 50, 376–399. [CrossRef]
74. Wang, X.; Chen, Y. Study on the safety evaluation of taurine, vitamin E and inositol complex powder. Clin. Res. Chin. Med. 2020, 12, 1–5.
75. Shu, Z.; Zhou, X.; Zhao, P.; Zhao, F. Toxicological safety evaluation of Qili taurine vitamin drink. Beverage Ind. 2016, 19, 5–9.
76. Zhao, K.; AI, F.; Zheng, L.; Chen, X.; Lin, J. Safety study of selenium-rich yeast and taurine formulated products. Strait J. Prev. Med. 2019, 25, 47–49.
77. Geng, K.J.; Liu, X. Safety and functionality of combined tablets of milk mineral salts and taurine. J. Food Saf. 2022, 2, 86–90. [CrossRef]
78. Duan, H.; Yan, W.J. Research progress on raw materials and their efficacious components for the function of relieving visual fatigue. Food Ind. Sci. Technol. 2022, 1–13. [CrossRef]
79. Kim, C.; Cha, Y.-N. Taurine chloramine produced from taurine under inflammation provides anti-inflammatory and cytoprotective effects. Amino Acids 2013, 46, 89–100. [CrossRef]
80. Marcinkiewicz, J.; Grabowska, A.; Bereta, J.; Stelmaszynska, T. Taurine chloramine, a product of activated neutrophils, inhibits in vitro the generation of nitric oxide and other macrophage inflammatory mediators. J. Leukoc. Biol. 1995, 58, 667–674. [CrossRef] [PubMed]
81. Schaffer, S.; Kim, H.W. Effects and Mechanisms of Taurine as a Therapeutic Agent. Biomol. Ther. 2018, 26, 225–241. [CrossRef]
82. Jong, C.J.; Azuma, J.; Schaffer, S. Mechanism underlying the antioxidant activity of taurine: Prevention of mitochondrial oxidant production. Amino Acids 2011, 42, 2223–2232. [CrossRef]
83. Nita, M.; Grzybowski, A. The Role of the Reactive Oxygen Species and Oxidative Stress in the Pathomechanism of Age-related Ocular Diseases and Other Pathologies of the Anterior and Posterior Eye Segments in Adults. Oxid. Med. Cell Longev. 2016, 2016, 3164734. [CrossRef]
84. Gaucher, D.; Arnault, E.; Husson, Z.; Froger, N.; Dubus, E.; Gondouin, P.; Dherbécourt, D.; Degardin, J.; Simonutti, M.; Fouquet, S.; et al. Taurine deficiency damages retinal neurons: Cone photoreceptors and retinal ganglion cells. Amino Acids 2012, 43, 1979–1993. [CrossRef] [PubMed]
85. Yu, X.; Chen, K.; Wei, N.; Zhang, Q.; Liu, J.; Mi, M. Dietary taurine reduces retinal damage produced by photochemical stress via antioxidant and anti-apoptotic mechanisms in Sprague–Dawley rats. mechanisms in Sprague-Dawley rats. Br. J. Nutr. 2007, 98, 711–719. [CrossRef] [PubMed]
86. García-Ayuso, D.; Di Pierdomenico, J.; Hadj-Said, W.; Marie, M.; Agudo-Barriuso, M.; Vidal-Sanz, M.; Villegas-Pérez, M.P. Taurine Depletion Causes ipRGC Loss and Increases Light-Induced Photoreceptor Degeneration. Investig. Ophthalmol. Vis. Sci. 2018, 59, 1396–1409. [CrossRef] [PubMed]
87. Martínez-Vacas, A.; Di Pierdomenico, J.; Gallego-Ortega, A.; Valiente-Soriano, F.J.; Vidal-Sanz, M.; Picaud, S.; Villegas-Pérez, M.P.; García-Ayuso, D. Systemic taurine treatment affords functional and morphological neuroprotection of photoreceptors and restores retinal pigment epithelium function in RCS rats. Redox Biol. 2022, 57, 102506. [CrossRef] [PubMed]
88. Castelli, V.; Paladini, A.; D’Angelo, M.; Allegretti, M.; Mantelli, F.; Brandolini, L.; Cocchiaro, P.; Cimini, A.; Varrassi, G. Taurine and oxidative stress in retinal health and disease. CNS Neurosci. Ther. 2021, 27, 403–412. [CrossRef]
89. Agarwal, R.; Arfuzir, N.N.N.; Iezhitsa, I.; Agarwal, P.; Sidek, S.; Ismail, N.M. Taurine protects against retinal and optic nerve damage induced by endothelin-1 in rats via antioxidant effects. Neural Regen. Res. 2018, 13, 2014–2021. [CrossRef] [PubMed]
90. Militante, J.; Lombardini, J.B. Age-Related Retinal Degeneration in Animal Models of Aging: Possible Involvement of Taurine Deficiency and Oxidative Stress. Neurochem. Res. 2004, 29, 151–160. [CrossRef]
91. Wang, Y.; Grenell, A.; Zhong, F.; Yam, M.; Hauer, A.; Gregor, E.; Zhu, S.; Lohner, D.; Zhu, J.; Du, J. Metabolic signature of the aging eye in mice. Neurobiol. Aging 2018, 71, 223–233. [CrossRef]
92. Dayang, W.; Dongbo, P. Taurine reduces blue light-induced retinal neuronal cell apoptosis in vitro. Cutan. Ocul. Toxicol. 2018, 37, 240–244. [CrossRef]
93. Park, J.-S.; Park, J.-H.; Kim, K.-Y. Neuroprotective effects of myristargenol A against glutamate-induced apoptotic HT22 cell death. RSC Adv. 2019, 9, 31247–31254. [CrossRef]
94. Araszkiewicz, A.; Zozulinska-Ziolkiewicz, D. Retinal neurodegeneration in the course of diabetes-pathogenesis and clinical perspective. Curr. Neuropharmacol. 2016, 14, 805–809. [CrossRef] [PubMed]
95. Ishikawa, M. Abnormalities in Glutamate Metabolism and Excitotoxicity in the Retinal Diseases. Scientifica 2013, 2013, 528940. [CrossRef] [PubMed]
96. Choi, D. Glutamate neurotoxicity and diseases of the nervous system. Neuron 1988, 1, 623–634. [CrossRef] [PubMed]
97. Agarwal, R.; Agarwal, P. Rodent models of glaucoma and their applicability for drug discovery. Expert Opin. Drug Discov. 2017, 12, 261–270. [CrossRef] [PubMed]
98. Leon, R.; Wu, H.; Jin, Y.; Wei, J.; Buddhala, C.; Prentice, H.; Wu, J.Y. Protective function of taurine in glutamate-induced apoptosis in cultured neurons. J. Neurosci. Res. 2009, 87, 1185–1194. [CrossRef]
99. Bulley, S.; Shen, W. Reciprocal regulation between taurine and glutamate response via Ca2+- dependent pathways in retinal third-order neurons. J. Biomed. Sci. 2010, 17 (Suppl. 1), S5. [CrossRef]
100. Yu, X.; Xu, Z.; Mi, M.; Xu, H.; Zhu, J.; Wei, N.; Chen, K.; Zhang, Q.; Zeng, K.; Wang, J.; et al. Dietary taurine supplementation ameliorates diabetic retinopathy via anti-excitotoxicity of glutamate in streptozotocin-induced Sprague-Dawley rats. excitotoxicity of glutamate in streptozotocin-induced Sprague-Dawley rats. Neurochem. Res. 2007, 33, 500–507. [CrossRef]
101. Oliveira, M.W.; Minotto, J.B.; de Oliveira, M.R.; Zanotto-Filho, A.; Behr, G.A.; Rocha, R.F.; Moreira, J.C.; Klamt, F. Scavenging and antioxidant potential of physiological taurine concentrations against different reactive oxygen/nitrogen species. Pharmacol. Rep. 2010, 62, 185–193. [CrossRef]
102. Jafri, A.J.A.; Agarwal, R.; Iezhitsa, I.; Agarwal, P.; Ismail, N.M. Taurine protects against NMDA-induced retinal damage by reducing retinal oxidative stress. Amino Acids 2019, 51, 641–646. [CrossRef]
103. Audo, I.; Mohand-Said, S.; Boulanger-Scemama, E.; Zanlonghi, X.; Condroyer, C.; Démontant, V.; Boyard, F.; Antonio, A.; Méjécase, C.; El Shamieh, S.; et al. MERTK mutation update in inherited retinal diseases. Hum. Mutat. 2018, 39, 887–913. [CrossRef]
104. Edwards, R.B.; Szamier, R.B. Defective Phagocytosis of Isolated Rod Outer Segments by RCS Rat Retinal Pigment Epithelium in Culture. Science 1977, 197, 1001–1003. [CrossRef] [PubMed]
105. Li, L.; Turner, J.E. Inherited retinal dystrophy in the RCS rat: Prevention of photoreceptor degeneration by pigment epithelial cell transplantation. Exp. Eye Res. 1988, 47, 911–917. [CrossRef] [PubMed]
106. Valiente-Soriano, F.J.; Salinas-Navarro, M.; Di Pierdomenico, J.; García-Ayuso, D.; Lucas-Ruiz, F.; Pinilla, I.; Cuenca, N.; Vidal-Sanz, M.; Villegas-Pérez, M.P.; Agudo-Barriuso, M. Tracing the retina to analyze the integrity and phagocytic capacity of the retinal pigment epithelium. Sci. Rep. 2020, 10, 7273. [CrossRef] [PubMed]
107. García-Ayuso, D.; Di Pierdomenico, J.; Vidal-Sanz, M.; Villegas-Pérez, M.P. Retinal Ganglion Cell Death as a Late Remodeling Effect of Photoreceptor Degeneration. Int. J. Mol. Sci. 2019, 20, 4649. [CrossRef] [PubMed]
108. Di Pierdomenico, J.; García-Ayuso, D.; González-Herrero, M.E.R.; García-Bernal, D.; Blanquer, M.; Bernal-Garro, J.M.; GarcíaHernández, A.M.; Vidal-Sanz, M.; Villegas-Pérez, M.P. Bone Marrow-Derived Mononuclear Cell Transplants Decrease Retinal Gliosis in Two Animal Models of Inherited Photoreceptor Degeneration. Int. J. Mol. Sci. 2020, 21, 7252. [CrossRef]
109. Di Pierdomenico, J.; Scholz, R.; Valiente-Soriano, F.J.; Sánchez-Migallón, M.C.; Vidal-Sanz, M.; Langmann, T.; Agudo-Barriuso, M.; García-Ayuso, D.; Villegas-Pérez, M.P. Neuroprotective Effects of FGF2 and Minocycline in Two Animal Models of Inherited Retinal Degeneration. Investig. Ophthalmol. Vis. Sci. 2018, 59, 4392–4403. [CrossRef]
110. Dowling, J.E.; Sidman, R.L. Inherited retinal dystrophy in the rat. J. Cell Biol. 1962, 14, 73–109. [CrossRef]
111. García-Ayuso, D.; Di Pierdomenico, J.; Agudo-Barriuso, M.; Vidal-Sanz, M.; Villegas-Pérez, M. Retinal remodeling following photoreceptor degeneration causes retinal ganglion cell death. Neural Regen. Res. 2018, 13, 1885–1886. [CrossRef]
112. García-Ayuso, D.; Salinas-Navarro, M.; Nadal-Nicol, F.M.; Ortín-Martínez, A.; Agudo-Barriuso, M.; Vidal-Sanz, M.; Villegas-Pérez, M.P. Sectorial loss of retinal ganglion cells in inherited photoreceptor degeneration is due to RGC death. Br. J. Ophthalmol. 2014, 98, 396–401. [CrossRef]
113. Villegas-P, M.P.; Lawrence, J.M.; Vidal-Sanz, M.; Lavail, M.M.; Lund, R.D. Ganglion cell loss in RCS rat retina: A result of compression of axons by contracting intraretinal vessels linked to the pigment epithelium. J. Comp. Neurol. 1998, 392, 58–77. [CrossRef]
114. Rascher, K.; Servos, G.; Berthold, G.; Hartwig, H.-G.; Warskulat, U.; Heller-Stilb, B.; Häussinger, D. Light deprivation slows but does not prevent the loss of photoreceptors in taurine transporter knockout mice. Vis. Res. 2004, 44, 2091–2100. [CrossRef] [PubMed]
115. Fan, Y.; Lai, J.; Yuan, Y.; Wang, L.; Wang, Q.; Yuan, F. Taurine Protects Retinal Cells and Improves Synaptic Connections in Early Diabetic Rats. Curr. Eye Res. 2019, 45, 52–63. [CrossRef] [PubMed]
116. García-Ayuso, D.; Di Pierdomenico, J.; Valiente-Soriano, F.J.; Martínez-Vacas, A.; Agudo-Barriuso, M.; Vidal-Sanz, M.; Picaud, S.; Villegas-Pérez, M.P. β-alanine supplementation induces taurine depletion and causes alterations of the retinal nerve fiber layer and axonal transport by retinal ganglion cells. Exp. Eye Res. 2019, 188, 107781. [CrossRef] [PubMed]
117. Horvath, G.-A.; Hukin, J.; Stockler-Ipsiroglu, S.; Aroichane, M. Eye findings on vigabatrin and taurine treatment in two patients with succinic semialdehyde dehydrogenase deficiency. Neuropediatrics 2016, 47, 263–267. [CrossRef] [PubMed]
118. Preising, M.N.; Görg, B.; Friedburg, C.; Qvartskhava, N.; Budde, B.S.; Bonus, M.; Toliat, M.R.; Pfleger, C.; Altmüller, J.; Herebian, D.; et al. Biallelic mutation of human SLC6A6 encoding the taurine transporter TAUT is linked to early retinal degeneration. FASEB J. 2019, 33, 11507–11527. [CrossRef]
119. Jammoul, F.; Dégardin, J.; Pain, D.; Gondouin, P.; Simonutti, M.; Dubus, E.; Caplette, R.; Fouquet, S.; Craft, C.M.; Sahel, J.A.; et al. Taurine deficiency damages photoreceptors and retinal ganglion cells in vigabatrin-treated neonatal rats. Mol. Cell Neurosci. 2010, 43, 414–421. [CrossRef]
120. Tao, Y.; Yang, J.; Ma, Z.; Yan, Z.; Liu, C.; Ma, J.; Wang, Y.; Yang, Z.; Huang, Y.F. The Vigabatrin Induced Retinal Toxicity is Associated with Photopic Exposure and Taurine Deficiency: An In Vivo Study. Cell Physiol. Biochem. 2016, 40, 831–846. [CrossRef]
121. Lambuk, L.; Iezhitsa, I.; Agarwal, R.; Bakar, N.S.; Agarwal, P.; Ismail, N.M. Antiapoptotic effect of taurine against NMDA-induced retinal excitotoxicity in rats. Neurotoxicology 2018, 70, 62–71. [CrossRef]
Disclaimer/Publisher's Note: The statements, opinions, and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions, or products referred to in the content.
【For more info:george.deng@wecistanche.com / WhatsApp:8613632399501】
