Inhibitory effect of vitamin D3 on 3'methyl-4-dimethyl-amino-azobenzene-induced rat hepatocarcinogenesis: a study on antioxidant defense enzymes

The association of vitamin D status with oxidative stress biomarkers and matrix metalloproteinases in patients with knee osteoarthritis

Objective

The association of vitamin D status with osteoarthritis (OA) has been demonstrated previously. The current study was performed to examine the association of vitamin D status with oxidative stress markers and matrix metalloproteinases (MMPs) in patients with knee OA.

Methods

This case-control study was conducted on 124 subjects with mild to moderate knee OA and 65 healthy controls. Demographic data was collected from all participants at baseline. Serum levels of vitamin D as well as markers of oxidative stress including malondialdehyde (MDA), total oxidant status (TOS), superoxide dismutase (SOD), oxidative stress index (OSI), paraoxonase-1 (PON-1), glutathione peroxidase (GPX), catalase (CAT), and total antioxidant capacity (TAC) were evaluated for each participant. Furthermore, serum concentrations of MMP-1, MMP-3, MMP-13, and cartilage oligomeric matrix protein (COMP) were measured.

Results

The results of the present study indicated that individuals with vitamin D insufficiency had higher levels of MDA, TOS, SOD, and OSI as well as lower levels of PON-1 and TAC. Based on the linear regression analysis, serum vitamin D levels were inversely correlated with MDA, TOS, SOD, OSI, MMP-1, and MMP-13 and positively associated with TAC levels (p < 0.0001). Patients with sufficient vitamin D levels had lower MMP-1 and MMP-13 levels compared to patients with vitamin D insufficiency (p < 0.001 and p < 0.001, respectively).

Conclusion

Findings from this study showed a strong association between vitamin D deficiency and increased oxidative stress and MMPs activity in patients with knee OA.

Role of Vitamin D in Liver Disease and Complications of Advanced Chronic Liver Disease

Vitamin D is a crucial nutrient with many pleiotropic effects on health and various chronic diseases. The purpose of this review is to provide a detailed report on the pathophysiological mechanisms underlying vitamin D deficiency in patients with chronic liver disease, addressing the different liver etiologies and the condition of advanced chronic liver disease (cirrhosis) with related complications. To date, patients with liver disease, regardless of underlying etiology, have been shown to have reduced levels of vitamin D. There is also evidence of the predictive role of vitamin D values in complications and progression of advanced disease. However, specific indications of vitamin D supplementation are not conclusive concerning what is already recommended in the general population. Future studies should make an effort to unify and validate the role of vitamin D supplementation in chronic liver disease.

Vitamin D3 supplementation alleviates chemically-induced cirrhosis-associated hepatocarcinogenesis

Vitamin D₃ (VD₃) deficiency has been associated with increased risk for cirrhosis and hepatocellular carcinoma, a highly incident malignant neoplasia worldwide. On the other hand, VD₃ supplementation has shown some beneficial effects in clinical studies and rodent models of chronic liver disease. However, preventive effects of dietary VD₃ supplementation in cirrhosis-associated hepatocarcinogenesis is still unknow. To investigate this purpose, male Wistar rats submitted to a combined diethylnitrosamine- and thioacetamide-induced model were concomitantly supplemented with VD₃ (5,000 and 10,000 IU/kg diet) for 25 weeks. Liver samples were collected for histological, biochemical and molecular analysis. Serum samples were used to measure 25-hydroxyvitamin D [25(OH)D] and alanine aminotransferase levels. Both VD₃ interventions decreased hepatic collagen deposition and pro-inflammatory p65 protein levels, while increased hepatic antioxidant catalase and glutathione peroxidase activities and serum 25(OH)D, without a clear dose-response effect. Nonetheless, only the highest concentration of VD₃ increased hepatic protein levels of VD receptor, while decreased the number of large preneoplastic glutathione-S-transferase- (>0.5 mm²) and keratin 8/18-positive lesions, as well the multiplicity of hepatocellular adenomas. Moreover, this intervention increased hepatic antioxidant Nrf2 protein levels and glutathione-S-transferase activity. In summary, dietary VD₃ supplementation - in special the highest intervention - showed antifibrotic and antineoplastic properties in chemically-induced cirrhosis-associated hepatocarcinogenesis. The positive modulation of Nrf2 antioxidant axis may be mechanistically involved with these beneficial effects, and may guide future clinical studies.

Effect of Vitamin D on Paraxonase-1, Total Antioxidant Capacity, and 8-Isoprostan in Children with Attention Deficit Hyperactivity Disorder

METHOD

In this double-blind, randomized, placebo-controlled trial, 75 children (aged 6-12) diagnosed with ADHD were randomly assigned into two groups. The supplementation group received vitamin D3 (2000 IU), and the control group received a placebo for 3 months. Blood samples were collected at baseline and after intervention to analyze the 25(OH)D, paraxonase-1 activity (PON-1), Total Antioxidant Capacity (TAC), and 8-isoprostan levels.

RESULTS

A significant rise in circulating 25(OH)D was observed in the vitamin D group versus the placebo group at the end of the study. There was no reduction in 8-isoprostan levels in the vitamin D group compared to the placebo group. Serum paraxonase-1 and TAC concentration decreased in both groups, but these alterations were not statistically significant in the treatment group versus the placebo group at the end of the intervention.

CONCLUSION

Vitamin D supplementation for 3 months did not have beneficial effects on biomarkers of oxidative stress status. To confirm these findings, further studies on children are suggested.

Vitamin D: Possible Therapeutic Roles in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a unique type of liver cancer instigated by underlying liver diseases. Pre-clinical evidence suggests that HCC progression, like other cancers, could be aided by vitamin D deficiency. Vitamin D is a lipid-soluble hormone usually obtained through sunlight. Vitamin D elucidates its biological responses by binding the vitamin D receptor; thus, promoting skeletal mineralization, and maintain calcium homeostasis. Other reported Vitamin D functions include specific roles in proliferation, angiogenesis, apoptosis, inflammation, and cell differentiation. This review highlighted studies on vitamin D's functional roles in HCC and discussed the specific therapeutic targets from various in vivo, in vitro and clinical studies over the years. Furthermore, it described recent advancements in vitamin D's anticancer effects and its metabolizing enzymes' roles in HCC development. In summary, the review elucidated specific vitamin D-associated target genes that play critical functions in the inhibition of tumorigenesis through inflammation, oxidative stress, invasion, and apoptosis in HCC progression.

Role of Vitamin D on glycemic control and oxidative stress in type 2 diabetes mellitus

Background:

Vitamin D deficiency may play a key role in the development of impaired glucose tolerance, type 2 diabetes mellitus (T2DM), and metabolic syndrome. Several studies have shown that Vitamin D has an antioxidant property. We aimed to investigate 25-hydroxy Vitamin D (25[OH]D) levels in patients with T2DM and in nondiabetic healthy controls and to ascertain the impact of 25(OH)D levels on glycemic control and oxidative stress in T2DM patients.

Materials and Methods:

Thirty male patients with T2DM and twenty age- and socioeconomic status-matched male healthy controls were included in the study. Fasting and postprandial blood sugar and glycated hemoglobin (HbA1c) were measured. Enzyme activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx) was determined by spectrophotometric assay, and serum levels of 25(OH)D were measured using radioimmunoassay.

Results:

Serum Vitamin D levels were significantly lower in patients with T2DM than healthy controls (P = 0.015). There was a significantly lower GPx activity in patients with T2DM than controls (P = 0.048), but the difference in SOD activity did not reach statistical significance. There was a significant negative correlation between serum Vitamin D levels and HbA1c (P = 0.016), but no statistical correlation was shown between serum Vitamin D levels and GPx and SOD.

Conclusion:

We conclude that low level of Vitamin D might play a significant role in T2DM pathogenesis. Hence, Vitamin D supplementation may improve glycemic control and oxidative stress in T2DM.

Correlation between vitamin D levels and muscle fatigue risk factors based on physical activity in healthy older adults

PURPOSE

The purpose of this study was to investigate the relationship of serum vitamin D levels with physical activity, obesity, muscle fatigue biomarkers, and total antioxidant capacity (TAC) in healthy older adults.

METHODS

A total of 85 healthy older subjects aged 64-96 years were recruited in this study. Based on estimated energy expenditure scores, the participants were classified into three groups: inactive (n=25), moderate (n=20), and physically active (n=35). Serum 25(OH)D (25-hydroxy vitamin D) levels, metabolic syndrome parameters, TAC activity, muscle fatigue biomarkers (Ca, creatine kinase, lactic acid dehydrogenase, troponin I, hydroxyproline), physical activity, body fatness, and fatigue score (visual analog scale) were estimated using immunoassay techniques and prevalidated questionnaires, respectively.

RESULTS

Physical activity was estimated in 64.6% of the participants. Males showed higher physical activity (42.5%) compared to females (26.25%). Compared to participants with lower activity, significant reduction in body mass index, waist circumference, hips, fasting blood sugar, triglycerides, total cholesterol, HDL-cholesterol, and LDL-cholesterol were observed in moderate and physically active participants. Also, significant increase in the levels of serum 25(OH)D concentrations, calcium, and TAC activity along with reduction in the levels of muscle fatigue biomarkers: creatine kinase, lactic acid dehydrogenase, troponin I, hydroxyproline, and fatigue scores (visual analog scale) were reported in physically active participants compared to those of lower physical activity. In all participants, serum 25(OH)D concentrations correlated positively with Ca, TAC, physical activity scores, and negatively with body mass index, lipid profile, fatigue scores (visual analog scale), and muscle fatigue biomarkers. Stepwise regression analysis showed that serum 25(OH)D concentrations, physical activity, Ca, TAC, and demographic parameters explained approximately 61.4%-85.8% of reduction in both fatigue scores and muscle fatigue biomarkers with substantial improvement in muscle performance in healthy older adults.

CONCLUSION

The data showed that considerable levels of 25(OH)D concentrations, calcium intake, and lower obesity positively correlated with the improvement in the muscle relief and performance of physically active participants. These results demonstrate that 25(OH)D concentrations and calcium might prevent muscle fatigue by regulation of the biosynthesis of creatine kinase, lactic acid dehydrogenase, troponin I, and hydroxyproline via a proposed antifree radical mechanism reported by higher TAC activity. It was suggested that vitamin D status could be reported as a marker of the improvement of muscle performance, especially in healthy older adults with lower physical activity.

Wnt/beta-catenin signaling activates and determines hepatic zonal expression of glutathione S-transferases in mouse liver

Glutathione S-transferases (GSTs) play an essential role in the elimination of xenobiotic-derived electrophilic metabolites and also catalyze certain steps in the conversion of endogenous molecules. Their expression is controlled by different transcription factors, such as the antioxidant-activated Nrf2 or the constitutive androstane receptor. Here, we show that the Wnt/beta-catenin pathway is also involved in the transcriptional regulation of GSTs: GSTm2, GSTm3, and GSTm6 are overexpressed in mouse hepatomas with activating Ctnnb1 (encoding beta-catenin) mutations and in transgenic hepatocytes expressing activated beta-catenin. Inversely, GSTm expression is reduced in mice with hepatocyte-specific knock out of Ctnnb1. Activation of beta-catenin-dependent signaling stimulates GSTm expression in vitro. Activation of beta-catenin in mouse hepatoma cells activates GSTm3 promoter-driven reporter activity, independently of beta-catenin/T-cell factor sites, via a retinoid X receptor-binding site. By contrast, GSTm expression is inhibited upon Ras activation in mouse liver tumors and transgenic hepatocytes. Recent studies by different groups have shown that beta-catenin-dependent signaling is involved in the transcriptional control of "perivenous" expression of various cytochrome P450s in mouse liver, whereas Ras signaling was hypothesized to antagonize the perivenous hepatocyte phenotype. In synopsis with our present results, it now appears that the Wnt/beta-catenin pathway functions as a master regulator of the expression of both phase I and phase II drug-metabolizing enzymes in perivenous hepatocytes from mouse liver.

Head and neck cancer in India--review of practices for prevention policy

India, with a population of over a billion is likely to increase global concern on cancer, particularly that of head and neck. The increasing immigration of Indians is likely to influence other parts of the world and an analysis of cancer-related practices could serve as a model for defining cancer-prevention strategies across the globe. The objective of this study was to review the anti- and pro-carcinogenic practices in India pertaining to head and neck cancer. The published literature on practices, compounds/chemicals/crude reparations related to the head and neck cancer in India was retrieved for analysis, while unauthentic or local information was discarded. The anti-carcinogenic practices prevalent in India consisted of classically varied diet being predominantly vegetarian, along with spices, condiments, beverages etc. The pro-carcinogenic practices predominantly include all shades of alcoholism and tobacco intake. Moreover, the diverse culture of the country reflects unique regional practices. The enormous diversity in practices related to head and neck cancer in India is very unique and interesting. Cancer prevention strategies need to focus on these trends to define a better global prevention.

Ganglioneuroblastoma-associated vitamin D deficiency rickets

Vitamin D deficiency is the most common cause of rickets mainly in breast-fed dark-skinned, African or Asian children receiving inadequate sunlight exposure. We report a case of a 1.5 year-old Afro-Italian male infant living in South Italy who came to our observation with the typical clinical picture of vitamin D deficiency rickets. The child was exclusively breast-fed for 8 months without vitamin D supplements. Owing to the rarity of vitamin D deficiency rickets in the South of Italy he underwent several investigations, which demonstrated the association with an abdominal ganglioneuroblastoma. To our knowledge, ganglioneuroblastoma has never been reported in association with vitamin D deficiency rickets. Although the association between these 2 rare conditions may be coincidental, the protective action of vitamin D against cancer suggests that vitamin D deficiency might have contributed to the development of ganglioneuroblastoma in our patient.

Function of oval cells in hepatocellular carcinoma in rats

AIM: To study oval cells pathological characteristics and relationship with the occurrence of hepatocellular carcinoma (HCC); to observe the form and structural characteristics of oval cells; to explore the expression characteristics of C-kit, PCNA mRNA and c-myc gene during the occurrence and development of HCC and the effect of ulinastatin (UTI) on C-kit and PCNA expression.

METHODS: One hundred and twenty-five SD rats fed on 3,3'-diaminobenzidine (DAB) to construct HCC models were divided into control group, cancer-inducing group and UTI intervention group. In each group, rat liver samples were collected at weeks 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22 and 24 respectively to study pathological distribution characteristics of oval cells in the process of carcinogenesis under optical microscope. Oval cells were separated by the methods of improved density gradient centrifugation and their structural characteristics were observed under optical microscope and electronic microscope respectively; the oval cells expressing C-kit and PCNA in the collected samples were observed by the methods of immunohistochemistry and image analysis and the expression of c-myc mRNA was also detected by reverse transcription polymerase chain reaction (RT-PCR).

RESULTS: Oval cells proliferated firstly in the portal area then gradually migrated into hepatic parenchyma in the inducing group and intervention group. The oval cells distributed inside and outside the carcinoma nodes. The oval cells presented the characteristics of undifferentiated cells: a high ratio of nucleolus and cellular plasm and obvious nucleoli, rare organelle in plasm. Only a few mitochondria and endoplasmic reticulum and some villus-like apophysis on surface of cells could be seen. Cells stained with C-kit and PCNA antibody were mainly oval cells distributed in the portal area. The expression of c-myc mRNA increased with the progression of HCC. However, in the intervention group, UTI could retard its increase.

CONCLUSION: Oval cells work throughout the development of HCC, and might play important roles in this process. c-myc gene may be a kind of promoter gene of HCC, and play a key role in hepatic injury and development of HCC. UTI could retard the occurrence of HCC.