Protective effects of esculetin against doxorubicin-induced toxicity correlated with oxidative stress in rat liver: In vivo and in silico studies.

Doxorubicin (DOX) is widely used in cancer treatment but the dose-related toxicity of DOX on organs including the liver limit its use. Therefore, there is great interest in combining DOX with natural compounds with antioxidant properties to reduce toxicity and increase drug efficacy. Esculetin is a natural coumarin derivative with biological properties encompassing anti-inflammatory and antioxidant activities. In light of these properties, this study was meticulously crafted to investigate the potential of esculetin in preventing doxorubicin (DOX)-induced hepatotoxicity in Sprague-Dawley rats. The rats were divided into a total of six groups: control group, DOX group (administered DOX at a cumulative dose of 5 mg/kg intraperitoneally every other day for 2 weeks), E50 group (administered 50 mg/kg of esculetin intraperitoneally every day), E100 group (administered 100 mg/kg of esculetin intraperitoneally every day) and combined groups (DOX + E50 and DOX + E100) in which esculetin was administered together with DOX. The treatments, both with DOX alone and in combination with E50, manifested a reduction in catalase (CAT mRNA) levels in comparison to the control group. Notably, the enzymatic activities of superoxide dismutase (SOD), CAT, and glutathione peroxidase (GPx) witnessed significant decreases in the liver of rats treated with DOX. Moreover, DOX treatment induced a statistically significant elevation in malondialdehyde (MDA) levels, coupled with a concurrent decrease in glutathione (GSH) levels. Additionally, molecular docking studies were conducted. However, further studies are needed to confirm the hepatoprotective properties of esculetin and to precisely elucidate its mechanisms of action.

Naringenin Ameliorate Carbon Tetrachloride-Induced Hepatic Damage Through Inhibition of Endoplasmic Reticulum Stress and Autophagy in Rats.

Hepatic fibrosis emerges upon exposure of liver to various chemicals and if not treated, it develops various diseases such as cirrhosis and cancer. Carbon tetrachloride (CCl4) is a widely used toxin in animal models to develop hepatic fibrosis. Accumulation of unfolded proteins in cells causes stress in the endoplasmic reticulum (ER) and various mechanisms are involved in the cell to reduce the damage caused by these unfolding proteins. The most well known of these is the unfolded protein response. Further, autophagy works to remove these proteins if the damage cannot be repaired and is permanent. In our study, we investigated the effects of naringenin (NRG), a flavanon abundant in citrus fruits, on ER stress and autophagy in CCl4-injured rat liver. The animals were given 0.2 mL/kg of CCl4 for 10 days and treatment group was administered 100 mg/kg of NRG for 14 days. Histopathological examination was performed to show liver damage and to determine the therapeutic properties of the active substance. Transmission electron microscopy (TEM) analysis was carried out to establish cell level damage and effect of treatment. In addition, levels of ER stress and autophagy markers of liver were measured. According to our findings, TEM demonstrated positive effect of NRG and histological examinations reported ameliorative effects. In addition, NRG reduced levels of ER stress markers and inhibited autophagy significantly compared to CCl4-treated group. As a result, NRG significantly reduced damage in hepatocytes and provided a significant amelioration.

The Effects of Monosodium Glutamate and Tannic Acid on Adult Rats.

BACKGROUND: Monosodium glutamate (MSG) is a widely-used flavor enhancer and stabilizer in ready-made or packaged foods. The excessive use of MSG has been shown to increase oxidative stress in different organ systems and causes glucose metabolism disorders, obesity, and coronary diseases. OBJECTIVES: In this study, the antioxidant activity of tannic acid was investigated experimentally with respect to its protective effects against overdosed MSG-induced oxidative stress in rats. The study took place in Turkey in August 2013. METHODS: Four groups (n = 7) of three- to four-month-old Sprague-Dawley female rats were used in this study. The first group was the control, who were administered saline. The second group received tannic acid (50 mg/kg, 3 days) intraperitoneally (i.p.). The third group received MSG (2 g/kg, 7 days) i.p., and the fourth group received both tannic acid (50 mg/kg, 3 days, pretreatment) and MSG (2 g/kg, 7 days) i.p. The animals were euthanized ten days later. Blood was collected for determining the hematological values and blood glucose levels. Superoxide dismutase (SOD) and malondialdehyde (MDA) levels were determined in the brain, liver, and kidney homogenates, and in the erythrocyte hemolysate. Histopathological examination of the brain, liver, and kidneys was conducted through hematoxylin-eosin staining. RESULTS: The data showed that the tannic acid treatment statistically decreased the MDA levels in the brain tissues of the group administered MSG and tannic acid (P < 0.001) when compared to the corresponding values of the control group. The SOD activities in the blood hemolysates of the MSG and tannic acid group increased when compared to the corresponding values for the MSG group (P < 0.01). Additionally, we found that pretreatment with tannic acid reduced blood glucose levels in comparison to the levels of the MSG group (P = 0.029). The results of our study show that tannic acid pretreatment in adult rats decreased blood glucose levels and oxidative stress. CONCLUSIONS: In the literature, it was observed that short-term MSG exposure does not cause significant histological changes in the kidneys, liver, or brain cortex. These findings should be re-evaluated in additional long-term studies.

Is the 1254T>C polymorphism in the DMT1 gene associated with Parkinson's disease?

Parkinson's disease (PD) is a late-onset neurodegenerative disorder with both familial and sporadic presentation. The main pathological characteristic of PD is the death of dopaminergic neurons in the substantia nigra (SN) pars compacta. PD is the second most common neurodegenerative disease worldwide, after Alzheimer's disease. Recent studies have suggested increased levels of iron and iron-binding proteins in the brains of patients with PD. Divalent metal transporter 1 (DMT1) is one protein responsible for iron transport. Postmortem studies have shown an important increase in DMT1 levels in the SN of patients with PD. Our aim is to determine whether there is an association between DMT1 polymorphisms and PD. We analyzed two single nucleotide polymorphisms (1254T>C and IVS4+44C>A) in the DMT1 gene in patients with 97 Parkinson's disease and in 100 healthy controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). No association was found between the IVS4+44C>A polymorphism and PD, but the TT genotype and T allele of the 1254T>C polymorphism in the DMT1 gene were associated with PD (P=0.002 and P=0.012, respectively). In contrast to a previous study, our results suggest that the TT genotype and T allele of the 1254T>C polymorphism may be a risk factor for PD.