Taurine Attenuates Doxorubicin-Induced Toxicity on B16F10 Cells

Taurine induces upregulation of p53 and Beclin1 and has antitumor effect in human nasopharyngeal carcinoma cells in vitro and in vivo

Taurine is an amino acid that has several physiological functions. Previously, we reported the apoptosis-inducing effect of taurine in human nasopharyngeal carcinoma (NPC) cells in vitro. However, the effect of taurine on NPC cell growth in vivo has not been elucidated. Autophagy plays an important role in cell metabolism and exhibits antitumor effects under certain conditions. In this study, we investigated the effects of taurine on apoptosis- and autophagy-related molecules in NPC cells in vitro and in vivo. In our in vitro study, NPC cells (HK1-EBV) were treated with taurine, and Western blot and immunocytochemical analyses revealed that taurine co-upregulated Beclin 1 and p53, with autophagy upregulation. In the in vivo study, we used a nude mouse model with subcutaneous xenografts of HK1-EBV cells. Once the tumors reached 2-3 mm in diameter, the mice were provided with distilled water (control group) or taurine dissolved in distilled water (taurine-treated group) ad libitum (day 1) and sacrificed on day 13. The volume and weight of the tumors were significantly lower in the taurine-treated group. Using immunohistochemistry (IHC), we confirmed that taurine treatment reduced the distinct cancer nest areas. IHC analyses also revealed that taurine promoted apoptosis, as evidenced by an increase in cleaved caspase-3, accompanied by upregulation of p53. Additionally, taurine increased LC3B and Beclin 1 expression, which are typical autophagy markers. The present study demonstrated taurine-mediated tumor growth suppression. Therefore, taurine may be a novel preventive strategy for NPC.

Taurine as a Natural Antioxidant: From Direct Antioxidant Effects to Protective Action in Various Toxicological Models

Natural antioxidants have received tremendous attention over the last 3 decades. At the same time, the attitude to free radicals is slowly changing, and their signalling role in adaptation to stress has recently received a lot of attention. Among many different antioxidants in the body, taurine (Tau), a sulphur-containing non-proteinogenic β-amino acid, is shown to have a special place as an important natural modulator of the antioxidant defence networks. Indeed, Tau is synthesised in most mammals and birds, and the Tau requirement is met by both synthesis and food/feed supply. From the analysis of recent data, it could be concluded that the direct antioxidant effect of Tau due to scavenging free radicals is limited and could be expected only in a few mammalian/avian tissues (e.g., heart and eye) with comparatively high (>15-20 mM) Tau concentrations. The stabilising effects of Tau on mitochondria, a prime site of free radical formation, are characterised and deserve more attention. Tau deficiency has been shown to compromise the electron transport chain in mitochondria and significantly increase free radical production. It seems likely that by maintaining the optimal Tau status of mitochondria, it is possible to control free radical production. Tau's antioxidant protective action is of great importance in various stress conditions in human life, and is related to commercial animal and poultry production. In various in vitro and in vivo toxicological models, Tau showed AO protective effects. The membrane-stabilizing effects, inhibiting effects on ROS-producing enzymes, as well as the indirect AO effects of Tau via redox balance maintenance associated with the modulation of various transcription factors (e.g., Nrf2 and NF-κB) and vitagenes could also contribute to its protective action in stress conditions, and thus deserve more attention.

Taurine Has Potential Protective Effects against the Chronic Cardiotoxicity Induced by Doxorubicin in Mice

Doxorubicin (DOX) is an effective anticancer anthracycline drug; however, the cardiotoxicity limits its application. The aim of the present study was to investigate the potential protective effect of taurine against DOX-induced chronic cardiotoxicity in mice. We found that exogenous supplementation of taurine can inhibit the weight loss of mice caused by DOX. The increased activity of myocardial enzymes creatine kinase (CK) and lactate dehydrogenase (LDH) in response to DOX treatment were significantly hampered. In addition, taurine supplementation alleviated the decrease in superoxide dismutase (SOD) activity, glutathione (GSH) content, glutathione peroxidase 4 (Gpx4) expression, and the increase in malondialdehyde (MDA) content caused by DOX. Besides, taurine alleviated myocardial myofibrillar disruption and mitochondrial edema. Furthermore, our results showed that taurine decreased the expressions of cleaved caspase-3 and Bax/Bcl2, thereby inhibiting apoptosis. These collective data demonstrated that exogenous taurine supplementation has a potentially protective effect against the myocardial damage caused by doxorubicin in mice by enhancing antioxidant capacity and reducing oxidative damage and apoptosis.

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.