In silico AND BIOCHEMICAL STUDIES ON THE MODULATORY EFFECTS OF CALCIFEROL ON PROSTATE AND LIVER CANCER

Cancer is a large group of diseases characterised by the rapid proliferation of abnormal cells. This disease group contributes to global mortality, with prostate cancer (CaP) and hepatocellular carcinoma (HCC) at the forefront. The liver is one of the sites of synchronous distant metastases where metastatic prostate cancer spreads to. Incidentally, the increased prevalence of vitamin D (VD) deficiency is also a global public health challenge. VD is a lipid-soluble vitamin known for primary roles in skeletal mineralisation. However, it is crucial to understand VD’s role in carcinogenesis. This study examined VD metabolism in prostate cancer (CaP) and hepatocellular carcinoma (HCC). Bioinformatics techniques were used to evaluate dysregulated genomic networks in CaP and HCC. The expression of prostate cancer-related transcriptional factors was analysed with immunohistochemistry techniques. Also, in silico antioxidant and anti-inflammatory potentials of VD were evaluated using molecular docking. In the HCC in vivo study, rats were divided into four experimental groups. Groups one and two were administered 30 mg/kg diethylnitrosamine (DEN) for eleven weeks, with groups three and four receiving normal saline. Before DEN administration, endogenous VD was depleted. Additionally, groups one and three received VD-deficient diet, while groups two and four took VD diet. Using enzyme-linked immunosorbent assay (ELISA), various inflammatory cytokines and cancer biomarkers were evaluated, while quantification of antioxidant parameters and lipids were carried out using spectrophotometric methods. Findings from this study showed synergistic network of events between circadian rhythm (CR), inflammation, oxidative stress, and VD metabolism. In CaP and HCC, VD metabolic gene disruption resulted in significant (p < 0.05) alteration of CR genes. Also, significant (p < 0.05) correlations between the disrupted VD metabolic genes and CR genes, inflammatory, and oxidative stress genes were observed. Meanwhile, racial differences in the expression and correlations of CR gene networks were observed in CaP. Results from CaP studies showed significant (p < 0.05) differential expression of VD and CR genes in African Americans (AA) in comparison to European Americans (EA), which could account for more aggressive subtypes in AA. In silico studies showed varying types of VD are strong antioxidant and anti-inflammatory agents via respective binding to KEAP1, Interleukin 1 (IL-1β), and Tumour necrosis factor (TNF-α). Following the in silico analysis, in vivo rat experimental results also showed ameliorative effects of VD in oxidative stress and inflammation. In the rats, dietary VD significantly (p < 0.05) reduce oxidative stress through increased antioxidant enzyme activities, including glutathione S-transferase and nitric oxide. Furthermore, inflammatory effects were reduced with the inclusion of the VD diet. Increased IL-1β and TNF-α production observed in VD deficient group was systematically reduced (p < 0.05) with dietary VD. In line with other results from this study, histopathological examinations indicate dietary VD could prevent cancer progression at the inflammation stage. Therefore, VD deficiency as a part activates and triggers cancer deterioration through alteration of non-classical pathways. In conclusion, increased vitamin D uptake in deficient cases could play integral roles in mitigating cancer progression hence a possible cancer preventive regime

Hesperidin prevents lipopolysaccharide-induced endotoxicity in rats

Context: Lipopolysaccharide (LPS) is a major trigger of septic shock resulting in multiple organ damage through excessive stimulation of the host’s immune cells resulting in the release of cytokines. Previous studies have shown that hesperidin has several beneficial properties against inflammation and oxidative stress. Objective: The influence of hesperidin on endotoxemia, endothelial dysfunction, inflammation, and oxidative stress was investigated using a murine model of sepsis. Materials and methods: Rats were pretreated for 15 d with three doses (50 mg/kg, 100 mg/kg, and 200 mg/kg) of hesperidin prior to LPS administration. Afterwards, the levels of biomarkers of endotoxemia, endothelial dysfunction, and oxidative stress were assessed. Reverse transcriptase PCR technique was used to assess the expression of hepatic proinflammatory cytokines. Results: Hesperidin pretreatment significantly (p < 0.05) reduced circulating endotoxin, as well as the levels of bactericidal permeability increasing protein and procalcitonin, and the associated endothelial dysfunction by reducing the levels of plasma soluble intercellular adhesion molecules 1 and inducible nitric oxide (iNO) synthase. There was also down-regulation of the expression of gene for interleukin 1α, interleukin 1β, interleukin 1 receptor, interleukin 6, and tumor necrosis factor α (TNFα) in the liver of rats treated with LPS as a result of hesperidin pretreatment. Hesperidin also showed anti-oxidative properties through the significant (p < 0.05) reduction of NO, hydroperoxides, and thiobarbituric acid reactive substances and increase of glutathione, glutathione reductase, glutathione peroxidase, and glutathione-S-transferase in the organs. Conclusion: Different doses of hesperidin can prevent endotoxemia-induced oxidative stress as well as inflammatory and endothelial perturbation in rats when administered for as few as 15 d before exposure to endotoxin

Naringin enhances reverse cholesterol transport in high fat/low streptozocin induced diabetic rats

Naringin, a citrus-derived flavonoid with antihyperglycemic, antihyperlipidemic, and antioxidant properties, is reported to be a useful nutraceutical in the management of diabetes and its complications. This study investigated the mechanism of antiatherogenic properties of naringin in type 2 diabetes (T2DM) using high fat-low streptozocin rat model of T2DM. Rats were treated daily with 50, 100 and 200 mg/kg naringin orally for 21days. Levels of biomarkers of T2DM, lipid profile and activity of paraoxonase (PON) were assayed spectrophotometrically. The levels of expression of hepatic 3-hydroxy-3-methyl-glutaryl-CoA reductase (Hmgcr), scavenger receptor class B member 1 (Scarb1), aryl hydrocarbon receptor (Ahr), hepatic Lipase (Lipc), and lecithincholesterol acyltransferase (Lcat) were assessed using relative reverse transcriptase polymerase chain reaction technique. Naringin treatment resulted in a dose-dependent significant (p < 0.05) decrease in the levels of plasma cholesterol and triglyceride from 84.84 ± 1.62 to 55.59 ± 1.50 mg/dL and 123.03 ± 15.11 to 55.00 ± 0.86 mg/dL, respectively, at 200 mg/kg naringin. In the liver, Scarb1 and Ahr were significantly (p < 0.05) upregulated at 200 mg/kg naringin while Lipc and Lcat were significantly (p < 0.05) upregulated by 50 mg/kg naringin. T2DM-induced decrease in PON activities in the plasma, liver and HDL was significantly (p < 0.05) reversed by 200 mg/kg naringin treatment. These genes play critical roles in reverse cholesterol transport and hence our results showed that the antiatherogenic property of naringin in T2DM involves enhancement of reverse cholesterol transport and PON activity

Time-Course Effects of Acute Aflatoxin B1 Exposure on Hepatic Mitochondrial Lipids and Oxidative Stress in Rats

Aflatoxins are secondary metabolites of certain Aspergillus species, that contaminate staple foods, particularly in developing countries. Aflatoxin B1 (AFB1) is the most toxic and common of the major types of aflatoxins. AFB1 is hepatotoxic and has been implicated in increasing the risk of hepatocellular carcinoma (HCC). We have previously shown that subacute exposure to AFB1 for 7 days disrupts hepatic lipids; therefore, this study determined the timecourse effects of acute aflatoxin exposure on hepatic mitochondrial lipids and oxidative stress. To achieve this, thirty male albino rats were randomly assigned to six groups. The groups received an oral dose of 1 mg/kg body weight AFB1 or vehicle only (controls) for one, four, or seven days, respectively. Twenty-four hours after the last dose, the animals were sacrificed and liver excised. Mitochondria and cytosolic fractions were obtained from the liver after which lipids (cholesterol, triacylglycerols) were determined in the mitochondria while biomarkers of oxidative stress (glutathione, glutathione transferase (GST), glutathione peroxidase (GPx), glutathione reductase, nitric oxide (NO), malonaldehyde (MDA), thioredoxin reductase (TR), and superoxide dismutase (SOD) were determined spectrophotometrically in the mitochondria and cytosolic fractions. The expression of genes (Nrf2, Acc, Nqo1, and HmgCoa) were determined using quantitative RT-PCR Results showed that AFB1 significantly increased mitochondrial cholesterol at day seven (treatment vs. control, p = 0.016). It also increased the concentrations of NO and MDA at day one and day seven while the activity of GPx and concentration of GSH were increased at day seven (p = 0.030) and day one (p = 0.025) alone, respectively, compared to control. The activities of cytosolic GR (p = 0.014), TR (p = 0.046) and GST (p = 0.044) were increased at day seven. AFB1 significantly increased the expression of Nrf2 (p = 0.029) and decreased the expression of Acc (p = 0.005) at day one. This study revealed that AFB1 disrupts hepatic mitochondrial lipids and antioxidant capacity. These changes were dependent on the timing of exposure and did not follow a linear time-course trend. These alterations could be part of the hepatic mitochondria response mechanism to acute AFB1 toxicity

Effects of Naringin on Apoptosis and Oxidative Stress in Type 2 Diabetic Rats

Oxidative stress and apoptosis have been reported to play major roles in the pathogenesis of Type 2 Diabetes Mellitus (T2DM) through insulin resistance and β-cell dysfunction. Naringin is a citrus derived flavonoid that has been reported for its antioxidant properties. Even though effects of naringin in T2DM related oxidative stress has been reported, varying dose concentration in oxidative stress and mechanism of action involving T2DM related apoptosis is far-fetched. This research studied the effects of naringin at varying dose concentration on apoptosis, biomarkers of organ function and oxidative stress in high fat diet/low-streptozotocin-induced T2DM in albino Wistar rats. Diabetic rats were treated with naringin at 50mg/kg, 100mg/kg and 200mg/kg body weight for 21 days. Some biomarkers of organ function and oxidative stress in the animals were assayed using spectrophotometric techniques. The levels of expression of caspases and apoptotic regulators were quantified using semi-quantitative reverse transcriptase polymerase chain reaction (RT PCR). Enzyme - linked immunosorbent assay was used to determine inducible nitric oxide synthase (iNOS) level. Naringin treatment shows a dose dependent significant (p<0.05) reduction in the plasma concentration of γ- glutamyltransferase, alkaline phosphatase and aspartate aminotransferase. Increasing dosage of Naringin significantly (p<0.05) reduced lipid peroxidation, glutathione- s-transferase, glutathione peroxidase and glutathione reductase activities in the liver. Naringin treatment also showed a significant (p<0.05) increase in the expression of caspase 3 and reduction in BCL-2 as against the diabetic control. In addition, there was dose dependent decrease in plasma CO2 concentration and increase in the plasma iNOS concentration as compared to the diabetic control. This result highlights positive effect of naringin as an antioxidant, its role in apoptosis and also reverting the effects of organ damage in type 2 diabetes

Effects of Quercetin on L-Arginine-Induced Acute Pancreatitis in Rats

This study evaluated the effect of quercetin on oxidative stress in a rat model of L-arginine-induced acute pancreatitis. Thirty male rats were randomly divided into five experimental groups thus: control, L-arginine group (2g/Kg body weight, i.p), and other groups were treated with 12.5mg/Kg body weight, 25mg/Kg body weight and 50mg/Kg body weight an hour after L-argnine administration. Twenty four hours thereafter, the rats were sacrificed and blood collected by cardiac puncture and organs were excised for the assay of plasma lipase and α-amylase activities as well as the activities of some antioxidant enzymes and levels of reduced glutathione, lipid peroxidation and chloramine. Acute pancreatitis was assessed by a significantly (p<0.05) increase in the activities of plasma lipase and α-amylase 24hours after L-arginine administration. All the quercetin dosages significantly (p<0.05) reversed the activities of these enzymes. L-arginine administration resulted in significant (p<0.05) reduction in the activity of glutathione-s-transferase in the lungs, pancreas and spleen as well as in the level of erythrocyte reduced glutathione. Only rats treated with 50mg/kg quercetin had a significant (p<0.05) reversal. However, all the quercetin treated groups had significant (p<0.05) increase in the level of erythrocyte reduced glutathione. Superoxide dismutase and peroxidase activities significantly (p<0.05) reduced while myeloperoxidase activity significantly (p<0.05) increased in the organs of rats as a result of L-arginine administration. These alterations were prevented by quercetin. These results show that quercetin protects the rat tissues from oxidative damage in L-arginine-induced pancreatitis.

Anti-inflammatory and antioxidant activities of fractions and compound from Ricinodendron heudelotii (Baill.)

Medicinal plants have been documented over the years to play vital role in promoting human health. The study evaluated the anti-inflammatory and anti-oxidant activities of different fractions and isolated compound from Ricinodendron heudelotii leaves. The leaves of Ricinodendron heudelotii were extracted with ethanol and further partitioned sequentially using petroleum ether, ethylacetate and butanol. Bioassay–guided fractionation of the ethylacetate fraction was done using repeated column chromatographic technique while the structural elucidation of pure compound was carried out using mass spectra, 13C and 1H NMR analyses. Antioxidant potential of the fractions and isolated compound were evaluated with 2,2-Azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays and anti-inflammatory effect of fractions was measured by their inhibitory potency on nitric oxide (NO). Corilagin, an amorphous tannin was isolated and structurally elucidated. Corilagin showed scavenging effect against ABTS and DPPH radicals which vary in a dose dependent manner. It also showed an antioxidant potential with IC50 value of 0.003 mg/mL comparable to vitamin C 0.001 mg/mL) used as standard. The butanol and ethylacetate fractions exhibited significant (p < 0.05) NO inhibition of 60 and 69% respectively after treatment of RAW 264.7 macrophages with lipopolysaccharide. These results demonstrated the role of isolated corilagin as a promising potent antioxidant while the ethylacetate and butanol fractions suppressed the expression of an inflammation mediator by inhibiting nitric oxide

Gas chromatography-mass spectrometry identification of anticancer phytochemicals in Aframomum danielli (LB579)

Aframomum danielli is one of the African spices used in folklore medicine for the management of several diseases. This study identified the phytochemical components present in the n-hexane seed extract of the A. danielli by gas chromatography-mass spectrometry (GC-MS) analysis and also evaluated the anti-cancer potential of the identified phytochemicals by performing molecular docking against human Vascular Endothelial Growth Factor (VEGF) using Molegro Virtual Docker. The GC-MS analysis identified the presence of phytochemical components caryophyllene (RT: 18.479), humulene (RT: 19.189), 2-butanone (RT: 22.976), benzenesulfonamide (RT: 31.651) and 2-pyridine acetic acid (RT: 32.446). 2-Butanone was the strongest binding ligand (-65.744 kcal/mol) while caryophyllene was the weakest bind lingand (-56.311 kcal/mol). These compounds showed relative strong docking to VEGF with docking energies comparable to an anticancer drug, bevacizumab (-77.883 kcal/mol). This in silico molecular docking study has shown that these phytochemical components could be responsible for anti-cancer properties of A. danielli

Effects of Ginger Juice Aflatoxin-Induced Oxidative Stress in Rats

This study was carried out to investigate the antioxidant properties of the fresh juice of ginger against aflatoxin-exposure in rats. The preventive potential and antioxidant capacity of the juice was evaluated by assaying the activities of antioxidant enzymes and lipid peroxidation content in some organs and erythrocytes of rats. Twenty rats were randomly divided into four experimental groups thus: group 1 served as control, group 2 received ginger juice (2mL/Kg of 10% juice)alone, group 3 received aflatoxins (3.65mg/kg body weight) alone while group 4 was pre-treated with ginger juice for 7days prior to aflatoxin administration. In the erythrocytes, aflatoxin treatment resulted in significant (p<0.05) increase in erythrocyte osmotic fragility and lipid peroxidation with a concomitant significant (p<0.05) decrease in the level of reduced glutathione. Pre-treatment of rats with ginger juice significantly (p<0.05) prevent these changes by maintaining the activity of superoxide dismutase and preventing the increase in lipid peroxidation in the organs. Ginger juice pre-treatment also significantly (p<0.05) increased the activities of hepatic glutathione-S-transferase, peroxidase and superoxide dismutase. It is concluded that ginger juice has preventive effect in rats with aflatoxicosis by promoting the antioxidant defense systems