Correlation of Clinical and Histopathological Grades in Oral Submucous Fibrosis Patients with Oxidative Stress Markers in Saliva

This study aimed to correlate the oxidative stress marker levels in saliva with the clinical stage based on mouth opening, fibrotic bands and histopathological grades of oral submucous fibrosis (OSF) patients. The study included patients clinically diagnosed with OSF (n = 63) and equal number of age and gender matched controls. Patients with OSF were defined by mouth opening stage, fibrotic bands and histopathological grades. Unstimulated saliva from both control and OSF patients were analysed for oxidative markers like lipid peroxides (LPO), non-enzymic antioxidants [reduced glutathione (GSH), vitamin A, vitamin E, vitamin C] and enzymatic antioxidants [glutathione peroxidase (GPx), superoxide dismutase (SOD)] and correlated with different stages and grades. Total salivary protein and LPO were significantly increased in OSF group with no significant change in the levels of GSH compared to controls. In OSF patients, a significant decrease in the levels of vitamins A, C and E was observed. The activities of salivary SOD and GPx were significantly decreased in OSF patients compared to controls. These changes significantly correlated with the increasing and differing grades of OSF that reflects increased oxidative stress with the progress of OSF.

Ulcer protective effect of Terminalia arjuna on gastric mucosal defensive mechanism in experimental rats

The methanol extract of the bark of Terminalia arjuna (Combretaceae) (TAE) showed marked antiulcer and ulcer healing activity against 80% ethanol (ETH), diclofenac sodium (DIC) and dexamethasone (DEX) induced ulcer models dose dependently at doses of 100, 400 and 200 mg/kg body weight respectively. Pre-, post and co-administration of TAE offered 100% protection to the gastric mucosa against ETH, DIC and DEX induced ulcers as observed from the ulcer score. Gastric mucosal analysis of DEX induced rats were associated with changes in the levels of protein, protein bound carbohydrate complexes, lipid peroxides (LPO), glutathione (GSH) and activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) compared with control rats. Co-administration with TAE in DEX rats (DEX + TAE) favorably altered the levels of LPO, GSH and also the activities of SOD and CAT in gastric mucosa, whereas the activities of GPx remained unaltered in all groups. In DEX + TAE rats, the levels of protein and protein bound carbohydrate complexes were increased when compared with DEX rats. The results indicate that the gastroprotective effect of TAE is probably related to its ability to maintain the membrane integrity by its antilipid peroxidative activity that protects the gastric mucosa against oxidative damage and its ability to strengthen the mucosal barrier, the first line of defense against exogenous and endogenous ulcerogenic agents.

Regulation of Intracellular Calcium Levels and Urokinase Activity in MDA MB 231 Cells by Quercetin

BACKGROUND

The common plant bioflavonoid, quercetin, is cytotoxic to various tumor cell lines, particularly breast cancer, by affecting the protein-kinase-C-dependent signal pathways and by cell cycle regulation. However, its role in breast cancer metastasis has not been studied so far. Increased uPA activity is evident in highly metastatic breast cancer, which is calcium dependent.

METHODS

MDA MB 231 cells were treated with various concentrations of quercetin (15-45 microg/ml). The cytotoxic effect of quercetin was assessed by MTT assay and DNA fragmentation analysis. Intracellular calcium levels were measured using Fura-2, a specific Ca2+ fluorescence indicator. Calcium uptake and release in cells treated with quercetin were measured using radioactive 45Ca2+. Urokinase enzyme activity was assayed by a casein zymogram.

RESULTS

Quercetin elicited dose- and time-dependent cytotoxicity as evidenced by the MTT assay. The maximum effect was observed at 48 h with a quercetin concentration of (45 microg/ml). DNA agarose gel electrophoresis showed dose-dependent DNA fragmentation on quercetin treatment. Quercetin caused significant depletion of cytosolic calcium levels and decreased calcium uptake from the intracellular stores. Casein zymogram showed a marked reduction of urokinase activity as evident by clear lysis bands on a dark background on treatment with quercetin.

CONCLUSION

Quercetin was found to exhibit cytotoxicity in the highly invasive breast cancer cell line MDA MB 231 in a dose- and time-dependent manner. Quercetin inhibited calcium dependent urokinase activity and hence may prove to be an effective antimetastatic agent.

Histone H1 inhibits the proliferation of MCF 7 and MDA MB 231 human breast cancer cells

Purified histone H1 exerts extracellular functions suggesting novel histone functions. The cytotoxic effects of histone H1 have lead to its choice as a pharmacological tool in breast cancer. Hence the present study was aimed at investigating the effect of exogenous histone H1 on the proliferation of estrogen receptor positive (MCF 7) and estrogen receptor negative (MDA MB 231) human breast cancer cells. Cells were incubated with various concentrations of histone H1 and antiproliferative activity was assessed by MTT assay. Proliferation of breast cancer cells was assessed from the activity of ornithine decarboxylase (ODC) using [(14)C] labeled ornithine. Histone H1-mediated cellular effects, such as anchorage dependent growth and apoptosis, were assessed by colony formation assay, fluorescence microscopy after acridine orange/propidium iodide staining and DNA fragmentation analysis. Histone H1 was significantly cytotoxic as it inhibited colony formation, ODC activity and induced apoptosis in both estrogen receptor positive and estrogen receptor negative cells. These results suggest that histone H1-induced antiproliferative effects on human breast cancer cells could possibly involve inhibition of ODC.

Cigarette smoking induces heat shock protein 70 kDa expression and apoptosis in rat brain: Modulation by bacoside A

Cigarette smoking is associated with the development of several diseases and antioxidants play a major role in the prevention of smoking-related diseases. Apoptosis is suggested as a possible contributing factor in the pathogenesis of smoking-induced toxicity. Therefore the present study was designed to investigate the influence of chronic cigarette smoke exposure on apoptosis and the modulatory effect of bacoside A (triterpenoid saponin isolated from the plant Bacopa monniera) on smoking-induced apoptosis in rat brain. Adult male albino rats of Wistar strain were exposed to cigarette smoke and simultaneously administered with bacoside A (10 mg/kg b.w./day, orally) for a period of 12 weeks. Expression of brain hsp70 was analyzed by Western blotting. Apoptosis was identified by DNA fragmentation, terminal deoxynucleotidyl transferase-mediated deoxy uridine triphosphate nick end labeling (TUNEL) staining and transmission electron microscopy. The results showed that exposure to cigarette smoke induced hsp70 expression and apoptosis as characterized by DNA laddering, increased TUNEL-positive cells and ultrastructural apoptotic features in the brain. Administration of bacoside A prevented expression of hsp70 and neuronal apoptosis during cigarette smoking. We speculate that apoptosis may be responsible for the smoking-induced brain damage and bacoside A can protect the brain from the toxic effects of cigarette smoking.

Effect of histone H1 on estrogen receptor status of human breast cancer MCF 7 cells

The effects of exogenous histone H1 on estrogen receptor status of human breast cancer MCF 7 cells were investigated in presence and absence of estrogen. Exogenous histone H1 was significantly cytotoxic in a dose- and time-dependent manner. Cell cycle analysis revealed a significant increase in the percentage of cell accumulation in G0/G1 phase. In histone H1-treated cells, a significant decrease in the estrogen receptor content and an increase in the dissociation constant (KD) of ER was observed compared to control.

Effect of bacoside A on brain antioxidant status in cigarette smoke exposed rats

Free radicals mediated oxidative stress has been implicated in the pathogenesis of smoking-related diseases and antioxidant nutrients are reported to prevent the oxidative damage induced by smoking. Therefore, the present study was conducted to evaluate the antioxidant role of bacoside A (triterpenoid saponin isolated from Bacopa monniera) against chronic cigarette smoking induced oxidative damage in rat brain. Adult male albino rats were exposed to cigarette smoke for a period of 12 weeks and simultaneously administered with bacoside A (10 mg/kg b.w./day, p.o.). Antioxidant status of the brain was assessed from the levels of reduced glutathione, vitamin C, vitamin E, and vitamin A and the activities of superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase. The levels of copper, iron, zinc and selenium in brain and serum ceruloplasmin activity were also measured. Oxidative stress was evident from the diminished levels of both enzymatic and non-enzymatic antioxidants. Alterations in the levels of trace elements with accumulation of copper and iron, and depletion of zinc and selenium were also observed. Bacoside A administration improved the antioxidant status and maintained the levels of trace elements. These results suggest that chronic cigarette smoke exposure enhances oxidative stress, thereby disturbing the tissue defense system and bacoside A protects the brain from the oxidative damage through its antioxidant potential.

Effect of bacoside A on membrane-bound ATPases in the brain of rats exposed to cigarette smoke

Membrane-bound enzymes play a vital role in neuronal function through maintenance of membrane potential and impulse propagation. We have evaluated the harmful effects of chronic cigarette smoking on membrane-bound ATPases and the protective effect of Bacoside A in rat brain. Adult male albino rats were exposed to cigarette smoke for a period of 12 weeks and simultaneously administered with Bacoside A (the active principle isolated from Bacopa monniera) at a dosage of 10 mg/kg b.w/day, p.o. The levels of lipid peroxides as marker for evaluating the extent of membrane damage, the activities of Na+/K+-ATPase, Ca2+-ATPase and Mg2+-ATPase, and associated cations sodium (Na+), potassium (K+), calcium (Ca2+), and magnesium (Mg2+) were investigated in the brain. Neuronal membrane damage was evident from the elevated levels of lipid peroxides and decreased activities of membrane-bound enzymes. Disturbances in the electrolyte balance with accumulation of Na+ and Ca2+ and depletion of K+ and Mg2+ were also observed. Administration of Bacoside A inhibited lipid peroxidation, improved the activities of ATPases, and maintained the ionic equilibrium. The results of our study indicate that Bacoside A protects the brain from cigarette smoking induced membrane damage.

Effect of Solanum trilobatum on the antioxidant status during diethyl nitrosamine induced and phenobarbital promoted hepatocarcinogenesis in rat

AIM

The methanolic extract of Solanum trilobatum (ST) is cytotoxic and exerts an inhibitory effect on tumor growth and in the present study, its role on the antioxidant status of N-diethylnitrosamine (DEN) induced and phenobarbital (PB) promoted hepatocarcinogenesis was assessed.

METHODS

The protective role of ST on DEN induced and PB promoted hepatocarcinogenesis in Wistar rats was assessed from total nodular incidence, nodule multiplicity and volume of persistent nodules after an experimental period of 3 and 6 months following co-administration. The levels of thiobarbituric reactive substances (TBARS), glutathione (GSH) and activities of antioxidant enzymes were assessed in the haemolysate and liver of experimental animals to evaluate the antioxidant status.

RESULTS

In DEN+PB+ST animals, the nodular incidence, multiplicity and volume reduced significantly compared to DEN+PB treated animals. In DEN+PB animals, the levels of TBARS increased significantly, whereas the levels of GSH and the activities of antioxidant enzymes-superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase and glucose 6 phosphate dehydrogenase showed significant alterations compared to control both in the haemolysate and liver. However, in DEN+PB+ST animals, the levels of TBARS decreased significantly and the levels of GSH increased with favorable alterations in the activities of antioxidant enzymes in both the haemolysate and liver.

CONCLUSION

The present results suggest that ST exerts its chemopreventive effects by modulating the antioxidant status during DEN induced hepatocarcinogenesis.

Protective Effect ofIndigofera oblongifoliain CCl4-Induced Hepatotoxicity

The present study aimed at assessing the protective effect of Indigofera oblongifolia on carbon tetrachloride (CCl4-induced hepatotoxicity. Hepatotoxicity was induced in male Wistar rats using CCl4 (1 mL/day at an interval of 72 hours). CCl4-induced animals were treated with I. oblongifolia at different doses. Hepatoprotection was assessed from activities of marker enzymes in serum and antioxidant status in the liver after an experimental period of 10 days. The activities of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase were significantly (P < .001) increased in serum of CCl4-induced animals when compared with control animals. Antioxidant status was significantly lowered in CCl4-treated animals with a significant (P < .001) increase in the levels of lipid peroxides [thiobarbituric acid-reactive substances (TBARS)], significantly lower levels of glutathione (GSH), and lowered activities of superoxide dismutase (SOD), catalase (CAT), and GSH peroxidase (GPx). The protective effect of I. oblongifolia was evident from lowering of levels of marker enzymes in serum and maintenance of antioxidant status in the liver as seen from lowered levels of TBARS, increased levels of GSH, and increased activities of SOD, CAT, and GPx. These results show the protective effect of I. oblongifolia and suggest the antioxidant property of the extract.

Histone H1 modulates the antioxidant status in 9,10-dimethylbenz[a]anthracene-induced experimental breast cancer

AIM

Oxidative stress is implicated in the pathogenicity of cancer cells and contributes towards the response to antineoplastic agents. This study was aimed at assessing the antioxidant status in 9,10-dimethylbenz[a]anthracene-induced experimental animals treated with histone H1.

METHODS

Histone H1 was injected and the antioxidant status was assessed in erythrocytes and tumour tissue of experimental animals. The antioxidant status was monitored from the levels of lipid peroxides as thiobarbituric acid reactants and conjugated dienes in the haemolysate, serum, glutathione, and plasma vitamins A, E, C and ceruloplasmin. In the haemolysate, activities of antioxidant enzymes, including superoxide dismutase, catalase, glutathione reductase, gamma-glutamyl transpeptidase, glutathione S-transferase, glutathione peroxidase and glucose-6-phosphate dehydrogenase, were assayed and erythrocyte fatty acid composition was analyzed by gas chromatography-mass spectrometry. All of the above parameters except fatty acid composition were assessed within the tumour tissue to assess the antioxidant status.

RESULTS

Treatment with histone H1 enhanced the antioxidant in erythrocyte at the end of the 2nd and 4th week by significantly decreasing thiobarbituric acid-reactive substances and conjugated dienes, by increasing glutathione levels, activities of antioxidant enzymes and favourably altering the erythrocyte fatty acid composition. Within the tumour tissue, a significant atrophy with significant alteration in antioxidant and antioxidant enzyme status was evident in treatment.

CONCLUSION

These results validate the role of histone H1 as an antitumour agent in breast cancer.

Creatine kinase isoenzyme patterns upon chronic exposure to cigarette smoke: protective effect of Bacoside A

Cigarette smoking is implicated as a major risk factor in the development of cardiovascular and cerebrovascular diseases. Creatine kinase (CK) and its isoforms (CK-MM, MB, BB) have been advocated as sensitive markers in the assessment of cardiac and cerebral damage. Therefore, in the present study, we report the isoenzyme patterns of CK in rats upon exposure to cigarette smoke and the protective effect of Bacoside A against chronic smoking induced toxicity. Adult male albino rats were exposed to cigarette smoke and simultaneously administered with Bacoside A, the active constituent from the plant Bacopa monniera, for a period of 12 weeks. The activity of CK was assayed in serum, heart and brain, and its isoenzymes in serum were separated electrophoretically. Rats exposed to cigarette smoke showed significant increase in serum CK activity with concomitant decrease in heart and brain. Also cigarette smoke exposure resulted in a marked increase in all the three isoforms in serum. Administration of Bacoside A prevented these alterations induced by cigarette smoking. Cigarette smoking is known to cause free radical mediated lipid peroxidation leading to increased membrane permeability and cellular damage in the heart and brain resulting in the release of CK into the circulation. The protective effect of Bacoside A on the structural and functional integrity of the membrane prevented the leakage of CK from the respective tissues, which could be attributed to its free radical scavenging and anti-lipid peroxidative effect.

Histone H1 modulates immune status in experimental breast cancer

BACKGROUND

Breast cancer chemotherapy aims at employing cytotoxic agents that swing the balance between tumor cell invasion and host immune cells in favor of the latter. This study aimed at assessing the effect of exogenous histone H1 in maintaining the immune status of animals in experimental breast cancer taking advantage of its tumor-suppressive activity.

METHODS

Histone H1 was injected intratumorally as a single injection in tumor-bearing animals. Tumor response was assessed from changes in tumor volume, survival time and the immune status of animals from total and differential blood cell counts, levels of circulating immune complexes, thromboxane B2 and IgA in serum. Immune response was assessed from the macrophage count in the tumor and peritoneal exudates after activation.

RESULTS

Histone H1 treatment significantly inhibited tumor growth, enhanced mean survival time and significantly improved the immune response and status.

CONCLUSION

These results indicate that histone H1 plays a vital role in maintaining the immune status.

Oxidative and non-oxidative activation of murine peritoneal macrophages by histone H1

The present study aimed at assessing the role of histone H1 in activating macrophages. Histone H1, injected intraperitoneally at a dose of 1 mg/kg body weight as multiple regimens weekly, significantly increased the number of peritoneal macrophages post 21 days of injection. The oxidative and non-oxidative activation of peritoneal macrophages by histone H1 was assessed. For the assessment of oxidative activation the levels of superoxide radical and nitric oxide radical were assessed. The oxidative activation was evident from release of significantly high levels of superoxide and nitric oxide radicals liberated by macrophages of animals treated with histone H1 (P < 0.001) than in untreated animals. In addition, the higher activities of superoxide dismutase indicated protective effect of histone H1, to keep away the macrophages from noxious effects of superoxide. The catalase activity was decreased significantly in macrophages of histone H1 treated animals. The levels of reduced glutathione were significantly (P < 0.001) lowered in treated animals, whereas the levels of lipid peroxides generated were non-significant. The non-oxidative activation was assessed from the activities of lysosomal enzymes released and also from cytolysis of NO-insensitive L929 cells. The activities of lysosomal enzymes-acid phosphatase and beta-glucuronidase released were significantly high in treated animals than in untreated animals (P < 0.001). Histone H1 stimulated the cytolysis of macrophages in L929 cells than in untreated animals. These results suggest that histone H1 stimulates macrophages by oxidative and non-oxidative mechanisms, which favor its future therapeutic prospects.

In vitro and in vivo adhesion testing of mucoadhesive drug delivery systems

Bioadhesive tablets were prepared by physical mixing of polymers and drug, then granulating and compressing into a tablet. The mucoadhesion was evaluated by shear stress measurement, detachment force measurement, and X-ray photography of the rabbit gastrointestinal tract. The strong interaction between the polymer and the mucous lining of the tissue helps increase contact time and permit localization. Polymers like hydroxypropyl methylcellulose K4M (HPMC K4M), hydroxypropyl methylcellulose 100 cps (HPMC 100 cps), carbopol-934, sodium carboxy methylcellulose (Na CMC), guar gum, and polyvinylpyrrolidone (PVP) were tested by shear stress measurement and detachment force measurement methods. HPMC K4M, showing maximum bioadhesion, was used in further studies. Adhesion was maximum between pH 5 and pH 6. Maximum adhesion was observed in the duodenum, followed by the jejunum and ileum. Barium sulfate (BaSO4) matrix tablets containing polymer and drug were subjected to X-ray studies in rabbits, and it was found that the tablet was mucoadhesive even after 8 hr. Enteric coating did not show any effect on mucoadhesion after passing from the stomach.