Water Soluble Vitamin E Administration in Wistar Rats with Non-alcoholic Fatty Liver Disease

The efficacy of vitamin E in preventing arthrofibrosis after joint replacement

BACKGROUND

Arthrofibrosis is a joint disorder characterized by excessive scar formation in the joint tissues. Vitamin E is an antioxidant with potential anti-fibroblastic effect. The aim of this study was to establish an arthrofibrosis rat model after joint replacement and assess the effects of vitamin E supplementation on joint fibrosis.

METHODS

We simulated knee replacement in 16 male Sprague-Dawley rats. We immobilized the surgical leg with a suture in full flexion. The control groups were killed at 2 and 12 weeks (n = 5 per group), and the test group was supplemented daily with vitamin E (0.2 mg/mL) in their drinking water for 12 weeks (n = 6). We performed histological staining to investigate the presence and severity of arthrofibrosis. Immunofluorescent staining and α2-macroglobulin (α2M) enzyme-linked immunosorbent assay (ELISA) were used to assess local and systemic inflammation. Static weight bearing (total internal reflection) and range of motion (ROM) were collected for functional assessment.

RESULTS

The ROM and weight-bearing symmetry decreased after the procedure and recovered slowly with still significant deficit at the end of the study for both groups. Histological analysis confirmed fibrosis in both lateral and posterior periarticular tissue. Vitamin E supplementation showed a moderate anti-inflammatory effect on the local and systemic levels. The vitamin E group exhibited significant improvement in ROM and weight-bearing symmetry at day 84 compared to the control group.

CONCLUSIONS

This model is viable for simulating arthrofibrosis after joint replacement. Vitamin E may benefit postsurgical arthrofibrosis, and further studies are needed for dosing requirements.

Pyrethroid-Induced Organ Toxicity and Anti-Oxidant-Supplemented Amelioration of Toxicity and Organ Damage: The Protective Roles of Ascorbic Acid and α-Tocopherol

The pyrethroid toxicants, fatal at high doses, are found as remnants of crop pesticides and ingredients of commercially available insecticides. The toxic effects of high-content insecticidal pyrethroid formulations are available in 0.05 g, 1.17 g, and 0.04 g pyrethroid-instilled products, namely burning coils, pyrethroid-soaked mats, and liquid formulations of pyrethroids that release pyrethroid vapor/smoke upon heating. They provided 5.46 g/kg, 21.15 g/kg, and 4.24 g/kg of toxicants to the experimental animals over a total of 3 weeks/5 h per os (p.o.) administration, producing necrosis, hyperemia, and fatty changes in the liver; fiber separation in cardiac muscles; atrophy, lymphatic infiltration, blood vessel congestion, and hyperemia in the heart tissues of the experimental animals. The glomerular tuft necrosis, cytoplasmic degeneration of renal tubular cells, necrotic tubules, congestion, and dilatation of blood vessels were observed in the kidney tissue of intoxicated animals. Air-space enlargement, interstitial inflammation, lymphocyte infiltration aggregates, connective tissue infiltration by inflammatory cells, and hyperemia were found in the lung tissues. The pyrethroid toxicants also produced nervous tissue degeneration and decreased neurons in the brain, which were observed through histopathological examinations of the brain, lungs, heart, kidneys, and liver. The protective effects of ascorbic acid (AA/vitamin C) and α-tocopherol (E307/vitamin E) at 100 mg/kg oral doses administered daily for the entire period of the toxicant exposure of three weeks to the experimental mice, aged between 3-4 months and weighing ≈30 g, ameliorated the tissue damage, as observed through the histopathological examinations. The ascorbic acid caused recovery of the liver, kidney, brain, and heart tissue damage, while α-tocopherol was effective at ameliorating the damage in the kidneys and lung tissue compared with the control groups. The high levels of tissue damage recovery suggested a prophylactic effect of the concurrent use of ascorbic acid and α-tocopherol for the subjects under the exposure of pyrethroids.

Phyllanthus Niruri Standardized Extract Alleviates the Progression of Non-Alcoholic Fatty Liver Disease and Decreases Atherosclerotic Risk in Sprague-Dawley Rats

Non-alcoholic fatty liver disease (NAFLD) is one of the major global health issues, strongly correlated with insulin resistance, obesity and oxidative stress. The current study aimed to evaluate anti-NAFLD effects of three different extracts of Phyllanthus niruri (P. niruri). NAFLD was induced in male Sprague-Dawley rats using a special high-fat diet (HFD). A 50% methanolic extract (50% ME) exhibited the highest inhibitory effect against NAFLD progression. It significantly reduced hepatomegaly (16%) and visceral fat weight (22%), decreased NAFLD score, prevented fibrosis, and reduced serum total cholesterol (TC) (48%), low-density lipoprotein (LDL) (65%), free fatty acids (FFAs) (25%), alanine aminotransferase (ALT) (45%), alkaline phosphatase (ALP) (38%), insulin concentration (67%), homeostatic model assessment of insulin resistance (HOMA-IR) (73%), serum atherogenic ratios TC/high-density lipoprotein (HDL) (29%), LDL/HDL (66%) and (TC-HDL)/HDL (64%), hepatic content of cholesterol (43%), triglyceride (29%) and malondialdehyde (MDA) (40%) compared to a non-treated HFD group. In vitro, 50% ME of P. niruri inhibited α-glucosidase, pancreatic lipase enzymes and cholesterol micellization. It also had higher total phenolic and total flavonoid contents compared to other extracts. Ellagic acid and phyllanthin were identified as major compounds. These results suggest that P. niruri could be further developed as a novel natural hepatoprotective agent against NAFLD and atherosclerosis.

Oxidative Stress as a Critical Factor in Nonalcoholic Fatty Liver Disease Pathogenesis

SIGNIFICANCE

Nonalcoholic fatty liver disease (NAFLD), characterized by liver triacylglycerol build-up, has been growing in the global world in concert with the raised prevalence of cardiometabolic disorders, including obesity, diabetes, and hyperlipemia. Redox imbalance has been suggested to be highly relevant to NAFLD pathogenesis. Recent Advances: As a major health problem, NAFLD progresses to the more severe nonalcoholic steatohepatitis (NASH) condition and predisposes susceptible individuals to liver and cardiovascular disease. Although NAFLD represents the predominant cause of chronic liver disorders, the mechanisms of its development and progression remain incompletely understood, even if various scientific groups ascribed them to the occurrence of insulin resistance, dyslipidemia, inflammation, and apoptosis. Nevertheless, oxidative stress (OxS) more and more appears as the most important pathological event during NAFLD development and the hallmark between simple steatosis and NASH manifestation.

CRITICAL ISSUES

The purpose of this article is to summarize recent developments in the understanding of NAFLD, essentially focusing on OxS as a major pathogenetic mechanism. Various attempts to translate reactive oxygen species (ROS) scavenging by antioxidants into experimental and clinical studies have yielded mostly encouraging results.

FUTURE DIRECTIONS

Although augmented concentrations of ROS and faulty antioxidant defense have been associated to NAFLD and related complications, mechanisms of action and proofs of principle should be highlighted to support the causative role of OxS and to translate its concept into the clinic. Antioxid. Redox Signal. 26, 519-541.

Relevant Aspects of Nutritional and Dietary Interventions in Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is the main cause of liver disease worldwide. NAFLD is linked to circumstances such as type 2 diabetes, insulin resistance, obesity, hyperlipidemia, and hypertension. Since the obesity figures and related comorbidities are increasing, NAFLD has turned into a liver problem that has become progressively more common. Currently, there is no effective drug therapy for NAFLD; therefore, interventions in lifestyles remain the first line of treatment. Bearing in mind that adherence rates to this type of treatment are poor, great efforts are currently focused on finding novel therapeutic agents for the prevention in the development of hepatic steatosis and its progression to nonalcoholic steatohepatitis and cirrhosis. This review presents a compilation of the scientific evidence found in the last years showing the results of interventions in lifestyle, diet, and behavioral therapies and research results in human, animal and cell models. Possible therapeutic agents ranging from supplementation with vitamins, amino acids, prebiotics, probiotics, symbiotics, polyunsaturated fatty acids and polyphenols to interventions with medicinal plants are analyzed.

Efficacy and mechanism of action of vitamin E in treatment of nonalcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is closely related to oxidative stress. Vitamin E (VE) is an effective antioxidant, which can relieve NAFLD symptoms by improving the balance between oxidation and anti-oxidation. However, recent research indicates that the mechanism of action of VE is not only limited to anti-oxidation, but also involves adjusting glucose and lipid metabolism disorders. Currently, the efficacy of VE in the treatment of NAFLD remains controversial, and its indications, dosage and treatment duration remain to be optimized. In this paper we review recent progress of clinical application of VE in the treatment of NAFLD and discuss the underlying mechanism.