Studies on the Respiratory Chain-linked Dihydrodiphosphopyridine Nucleotide Dehydrogenase

Mito-TEMPO mitigates 5-fluorouracil-induced intestinal injury via attenuating mitochondrial oxidative stress, inflammation, and apoptosis: an in vivo study

BACKGROUND

Recent evidences highlight role of mitochondria in the development of 5-fluorouracil (5-FU)-induced intestinal toxicity. Mitochondria-targeted antioxidants are well-known for their protective effects in mitochondrial oxidative stress- mediated diseases. In the present study, we investigated protective effect of Mito-TEMPO in 5-FU-induced intestinal toxicity.

METHODS

Mito-TEMPO (0.1 mg/kg b.w.) was administered intraperitoneally to male BALB/c mice for 7 days, followed by co-administration of 5-FU for next 4 days (intraperitoneal 12 mg/kg b.w.). Protective effect of Mito-TEMPO on intestinal toxicity was assessed in terms of histopathological alterations, modulation in inflammatory markers, apoptotic cell death, expression of 8-OhDG, mitochondrial functional status and oxidative stress.

RESULTS

5-FU administered animals showed altered intestinal histoarchitecture wherein a shortening and atrophy of the villi was observed. The crypts were disorganized and inflammatory cell infiltration was noted. Mito-TEMPO pre-protected animals demonstrated improved histoarchitecture with normalization of villus height, better organized crypts and reduced inflammatory cell infiltration. The inflammatory markers and myeloperoxidase activity were normalized in mito-TEMPO protected group. A significant reduction in intestinal apoptotic cell death and expression of 8-OhDG was also observed in mito-TEMPO group as compared to 5-FU group. Further, mtROS, mtLPO and mitochondrial antioxidant defense status were improved by mito-TEMPO.

CONCLUSION

Mito-TEMPO exerted significant protective effect against 5-FU-induced intestinal toxicity. Therefore, it may be used as an adjuvant in 5-FU chemotherapy.

Protective effects of β-caryophyllene on mitochondrial damage and cardiac hypertrophy pathways in isoproterenol-induced myocardial infarcted rats

The cardiac mitochondrial damage and cardiac hypertrophy pathways are intimately associated with the pathology of myocardial infarction (MI). The protective effects of β-caryophyllene on mitochondrial damage and cardiac hypertrophy pathways in isoproterenol-induced myocardial infarcted rats were investigated. Isoproterenol (100 mg/kg body weight) was administered to induce MI. The ST-segment, QT interval, and T wave were widened, and the QRS complex and P wave were shortened in the electrocardiogram (ECG) and the serum cardiac diagnostic markers and heart mitochondrial lipid peroxidation products, calcium ions, and reactive oxygen species (ROS) were elevated and the heart mitochondrial antioxidants, tricarboxylic acid cycle, and respiratory chain enzymes were lessened in isoproterenol-induced myocardial infarcted rats. The heart mitochondrial damage was noted in the transmission electron microscopic study. The whole heart weight was increased and the subunits of nicotinamide adenine dinucleotide phosphate - oxidase 2 (Nox 2) genes such as cybb and p22-phox and cardiac hypertrophy genes such as atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), β -myosin heavy chain (β-MHC), and actin alpha skeletal muscle-1(ACTA-1) were highly expressed in the rat's heart by reverse transcription-polymerase chain reaction study. The β-caryophyllene (20 mg/kg body weight) pre- and co-treatment orally, daily for 21 days reversed changes in ECG and lessened cardiac diagnostic markers, ROS, and whole heart weight and ameliorated mitochondrial damage and Nox/ANP/BNP/β-MHC/ACTA-1cardiac hypertrophy pathways in isoproterenol-induced myocardial infarcted rats. The observed effects might be due to the antioxidant, anti-mitochondrial damaging, and anti-cardiac hypertrophic mechanisms of β-caryophyllene.

Sesamol Supplementation Mitigates Isoproterenol-Induced Cardiac Toxicity in Rats by Stabilizing Cardiac Mitochondrial and Lysosomal Enzymes

The current investigation was intended to evaluate the antimyocardial ischemic effects of sesamol on lactate dehydrogenase (LDH) isoenzymes, DNA damage, and mitochondrial and lysosomal enzyme activities in isoproterenol (ISO)-induced myocardial infarction (MI) in male albino Wistar strain rats. Rats that received ISO (85 mg/kg body weight (B.W) subcutaneously) for the first 2 consecutive days showed significant reduction in the activities of tricarboxylic acid (TCA) cycle enzymes (isocitrate dehydrogenase, α-ketoglutarate dehydrogenase, malate dehydrogenase, and succinate dehydrogenase) and respiratory chain enzymes (cytochrome c oxidase and nicotinamide adenine dinucleotide hydrogen (NADH) dehydrogenase) in the heart mitochondria. The activities of the lysosomal enzymes (α-and β-glucosidases, α and β-galactosidases, β-glucuronidase and β-N-acetyl glucosaminidase and cathepsin-B and cathepsin-D) were increased significantly in the heart homogenate of ISO-induced MI rats. ISO injection also increased the % of tail DNA, tail length, and tail moment and decreased the % of head DNA. Pretreatment with sesamol (50 mg/kg B.W) every day for a period of 9 days prevented the above abnormalities induced by ISO. In conclusion, it can be inferred that administration of sesamol has a potent beneficial role against ISO-induced damage to the mitochondria, lysosomes, and DNA, thereby preventing MI.

An in vivo and in vitro model on the protective effect of corilagin on doxorubicin-induced cardiotoxicity via regulation of apoptosis and PI3-K/AKT signaling pathways

Globally, doxorubicin (DOX)-induced cardio dysfunction is a serious cause of morbidity and mortality in cancerous patients. An adverse event of cardiotoxicity is the main deem to restrict in the clinical application by oncologists. Corilagin (CN) is well known for its antioxidative, anti-fibrosis, and anticancer effects. Herein, we aimed to evaluate the action of CN on DOX-induced experimental animals and H9c2 cells. The myocardium-specific marker, CK-MB, and the influx of mitochondrial calcium levels were measured by using commercial kits. Biochemical indices reflecting oxidative stress and antioxidant attributes such as malondialdehyde, glutathione peroxidase, reduced glutathione, superoxide dismutase, and catalase were also analyzed in DOX-induced cardiotoxic animals. In addition, mitochondrial ROS were measured by DCFH-DA in H9c2 cells under fluorescence microscopy. DOX induction significantly increased oxidative stress levels and also modulated apoptosis/survival protein expressions in myocardial tissues. Western blots were used to measure the expressional levels of Bax/Bcl-2, caspase-3, PI3-K/AKT, and PPARγ signaling pathways. Histological studies were executed to observe morphological changes in myocardial tissues. All of these DOX-induced effects were attenuated by CN (100 mg/kg bw). These in vitro and in vivo results point towards the fact that CN might be a novel cardioprotective agent against DOX-induced cardiotoxicity through modulating cardio apoptosis and oxidative stress.

Acute toxicity studies and protective effects of Cinnamon cassia bark extract in streptozotocin-induced diabetic rats

The medicinal properties of Cinnamon cassia (C. cassia) bark have been reported for their clinical importance for many diseases including diabetes. However, there is no clear evidence so far regarding dose selection for its hepato- and nephroprotective effect in diabetic condition. Hence, the present study aims at evaluating in vitro antioxidant activity, the acute toxicity, and dose fixation of C. cassia bark for their effective medicinal values in streptozotocin (STZ)-induced rats. All the extracts exhibited potential in vitro antioxidant activity and showed a dose-dependent (1000, 2000, 3000, 4000, and 5000 mg/kg BW) acute toxicity by in vivo model. The levels of aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), urea, and creatinine showed a significant elevation in animals treated with the highest dose. In further studies along with histopathological studies, animals treated with STZ (60 mg/kg BW) followed by a different dose (300, 400, and 500 mg/kg BW) of ethanolic extract of the C. cassia bark and glibenclamide (3 mg/kg BW) revealed that the altered level of mitochondrial enzymes, hepatic, and renal marker in STZ-induced animals were restored in C. cassia bark extract-treated group as of control. These results could be of scientific support for the use of the ethanolic extract of the C. cassia bark in folk medicine for the management of diabetes and its associated complications.

Mitochondria-targeted antioxidant, mito-TEMPO mitigates initiation phase of N-Nitrosodiethylamine-induced hepatocarcinogenesis

Targeting mitochondrial oxidative stress during initial stages of hepatocarcinogenesis can be an effective and promising strategy to prevent hepatocellular carcinoma (HCC). In the present study, mitochondria targeted antioxidant, mito-TEMPO was administered to male BALB/c mice at a dosage 0.1 mg/kg b.w. (intraperitoneal) twice a week, followed by single N-Nitrosodiethylamine (NDEA) intraperitoneal injection (10 mg/kg b.w.). After 24 h of NDEA administration, animals were sacrificed, blood and liver tissue were collected. Liver injury markers, histoarchitecture, antioxidant defence status, mitochondrial reactive oxygen species (ROS), lipid peroxidation (LPO), mitochondrial dysfunction analysis, and mitochondrial membrane potential were investigated. Mito-TEMPO pre-treatment protected animals from the damaging effects of NDEA as observed by normalization of liver injury markers. NDEA metabolism resulted in a significantly increased intracellular and mitochondrial ROS generation with concomitant increase in LPO formation. The activity of mitochondrial complex I, complex II, malate dehydrogenase were significantly reduced and mitochondrial membrane potential was increased. Mito-TEMPO effectively scavenged NDEA-induced ROS generation and reduced LPO formation. A significant improvement was also observed in the activity of mitochondrial complex I, complex II, malate dehydrogenase and normalisation of mitochondrial membrane potential. Results suggested that mito-TEMPO had significant impact on the initiation phase of hepatocarcinogensis which could be one of the reason for its reported chemopreventive effect.

Hepatoprotective effects of Psidium guajava on mitochondrial enzymes and inflammatory markers in carbon tetrachloride-induced hepatotoxicity

OBJECTIVE

The present investigation was aimed to evaluate the hepatoprotective potential of ethanolic extract of Psidium guajava (P. guajva) and its isolated quercetin fraction on carbon tetrachloride (CCl₄)-induced hepatotoxicity.

MATERIALS AND METHODS

The rats were divided into 6 groups and each group contained 6 rats. CCl₄ (1.5 ml/kg b.w.) was used to induce the hepatotoxicity. Ethanolic extract of P. guajava (300 mg/kg b.w.), isolated quercetin fraction (20 mg/kg b.w.) were used as a treatment and silymarin (25 mg/kg b.w.) was used as a standard drug. After the study period, the liver tissues were collected and evaluate the levels of liver functional markers, mitochondrial enzymes, histopathological analysis and the expressions of inflammatory markers.

RESULTS

The levels of liver functional markers were increased and protein, albumin and A/G ratio levels were decreased and the decreased levels of mitochondrial enzymes were noted in CCl₄-induced rats and the levels were restored near to normal significantly when the administration ethanolic extract of P. guajava, isolated quercetin fraction and silymarin. The normal architecture of liver tissues were altered and the mRNA expressions were up-regulated in CCl₄-induced rats and the liver tissues were normalized and the mRNA and protein expressions were down-regulated near to normal significantly when the administration of ethanolic extract of P. guajava, isolated quercetin fraction and silymarin.

CONCLUSION

From these results, the isolated quercetin fractions have better activity than that of the ethanolic extract of P. guajava leaves. Hence, the isolated quercetin may be used as the safest drug for hepatotoxicity in future.

Sinapic acid safeguards cardiac mitochondria from damage in isoproterenol-induced myocardial infarcted rats

Myocardial infarction (MI) is a life-threatening disease. In this study, we examined the anti-mitochondrial damaging effects of sinapic acid (SA) in isoproterenol (ISO)-induced myocardial infarcted rats. Myocardial infarcted rats were prepared by injecting ISO (100 mg/kg body weight) on the 9th and 10th day. Rats were pretreated and cotreated with SA (12 mg/kg body weight) orally, daily for 10 days. A considerable increase in serum lactate dehydrogenase, creatine kinase, myoglobin, and cardiac troponin-T was noticed in the ISO-induced rats. ISO also significantly amplified lipid peroxidation and calcium ions, and depleted the antioxidant system and mitochondrial enzymes in rat's heart mitochondria. SA treatment improved the distorted above- mentioned biochemical parameters in ISO-treated rats with its anti-mitochondrial damaging effects. This ultrastructural study on heart mitochondria and in vitro studies also confirmed the effects of SA. The current findings are suggestive of SA's cardioprotective effects.

A magnetic nanoparticle functionalized reduced graphene oxide-based drug carrier system for a chemo-photodynamic cancer therapy

The proposed work shows the dual therapeutic impact of an external stimulus responsive CPT loaded MrGO-AA-g-4-HC carrier system for cancer treatments.

Ursolic acid modulates MMPs, collagen-I, α-SMA, and TGF-β expression in isoproterenol-induced myocardial infarction in rats

In the present study, the modulatory effect of ursolic acid (UA) on cardiac fibrosis and mitochondrial and lysosomal enzymes activity in isoproterenol-induced myocardial infarction (MI) in rats were examined. Isoproterenol hydrochloride (ISO; 85 mg/kg body weight) was administered subcutaneously for first two consecutive days. ISO-induced MI in rats significantly decreased the activities of mitochondrial tricarboxylic acid cycle enzymes and respiratory chain enzymes while increased the activities of lysosomal glycohydrolases and cathepsins. The expression of matrix metalloproteinase 2 (MMP-2), MMP-9, collagen type I, α-smooth muscle actin (α-SMA), and transforming growth factor-β (TGF-β) were upregulated in ISO-induced MI in rats. UA administration to rats showed increased activities of mitochondrial tricarboxylic acid cycle enzymes and respiratory chain enzymes and decreased activities of lysosomal glycohydrolases and cathepsins in ISO-induced rats. Furthermore, expression of MMP-2, MMP-9, collagen type I, α-SMA, and TGF-β downregulated in UA-administered rats. Thus, our results demonstrate that UA has an anti-fibrotic effect and attenuates the mitochondrial and lysosomal dysfunction in ISO-induced MI in rats.

Folate receptor targeted delivery of paclitaxel to breast cancer cells via folic acid conjugated graphene oxide grafted methyl acrylate nanocarrier

The adaptability, joint with a large surface area, electronic flexibility, high intrinsic mobility, high mechanical strength and supreme thermal conductivity have condensed graphene family materials attractive as technological tools of the drug delivery system. In this present study, investigate a modified graphene oxide-methyl acrylate (GO-g-MA) nanocarrier for targeted anti-cancer drug delivery in breast cancer cells and the GO-g-MA fascinated with folic acidas a targeting ligand to target the cancer cells. Paclitaxel (PTX) was assembled through π-π stacking, hydrophophic interaction on the surface of the GO-g-MA/FA carrier. Structural modification of GO-g-MA, functionalization of targeting ligands GO-g-MA/FA and drug loaded GO-g-MA/FA-PTX was characterized and confirmed through FTIR, XRD, SEM,TEM and AFM analysis. The in-vitro drug release pattern of PTX from the GO-g-MA/FA was examined in different pH ranges. An MTT assay was performed to evaluate the cytotoxicity behaviour of the carrier and PTX loaded nanocarrier in the human breast cancer cell line (MDA-MB-231). GO-g-MA/FA-PTX carrier showed that 39% of cytotoxic effect. Furthermore, the in-vivo (DMBA induced breast cancer rats) studies were carried out and treatment with PTX- loaded GO-g-MA/FA nanocarrier attenuates the levels of mitochondrial citric acids enzymes to near normal.

Berbamine ameliorates isoproterenol-induced myocardial infarction by inhibiting mitochondrial dysfunction and apoptosis in rats

Berbamine (BBM), a bisbenzylisoquinoline alkaloid from roots, bark, and stem of Berberis plant such as Berberis aristata has a wide range of pharmacological activities. However, the evidence for the cardioprotective effect of BBM is inadequate and the molecular mechanism of BBM remains unclear. This study investigated the underlying molecular mechanism of BBM-mediated cardioprotection on isoproterenol (ISO)-induced mitochondrial dysfunction and apoptosis in rats. The assays of mitochondria antioxidant status, mitochondrial marker enzymes, and electron microscopic analysis of mitochondria revealed BBM significantly prevented the mitochondrial dysfunction induced by ISO. The ISO-induced elevation of mitochondrial oxidative stress was also curbed by BBM. Furthermore, pretreatment with BBM protected the heart tissue from ISO-induced apoptosis as evident from decreased terminal dUTP nickend-labeling positive cells and decreased expression of Bax, cytochrome c, cleaved caspase-9, and caspase-3, and poly (ADP-ribose) polymerase and increased expression of Bcl-2 in ISO-induced rats. These current findings suggest that BBM exerts a significant cardioprotective effect on ISO-induced myocardial infarction in rats.

Cardioprotective effect of zingerone against oxidative stress, inflammation, and apoptosis induced by cisplatin or gamma radiation in rats

Despite their clinical benefits in cancer treatment, the deleterious effects on heart following chemo/radiotherapy are of increasing importance. Zingerone, a natural polyphenol, possesses multiple biological activities, such as antioxidant and anti-inflammatory. Thus, the current study was designed to assess the potential cardioprotective effects of zingerone against cisplatin or γ-radiation. Zingerone was given by intragastric intubation (25 mg/kg) daily for three successive weeks prior to the induction of cardiotoxicity using a single dose of cisplatin (20 mg/kg, i.p.) or a whole body γ-irradiation at a single dose of 6 Gy. Zingerone pre-treatment significantly reduced the abnormalities in heart histology and the increase in the cardiotoxicity indices, serum lactate dehydrogenase, and creatine kinase-MB activities, as well as plasma cardiac troponin T and B-natriuretic peptide, induced by cisplatin or γ-radiation. Further, zingerone, except for superoxide dismutase, notably ameliorated the state of oxidative stress as evidenced by a significant decrease in malondialdehyde level accompanied with a significant increase in the reduced glutathione content and catalase activity. Additionally, zingerone mitigated the increase in the inflammatory markers including serum level of tumor necrosis factor-alpha, cardiac myeloperoxidase activity, and cyclooxygenase-2 protein expression. Moreover, zingerone alleviated the elevation of caspase-3 gene expression and the prominent nuclear DNA fragmentation and attenuated the decrease in mitochondrial complexes' activities. This study sheds the light on a probable protective role of zingerone as an antioxidant, anti-inflammatory, and antiapoptotic agent against cisplatin- or γ-radiation-induced cardiotoxicity and holds a potential in regard to therapeutic intervention for chemo/radiotherapy mediated cardiac damage.

Lycopene Prevents Mitochondrial Dysfunction during d-Galactosamine/Lipopolysaccharide-Induced Fulminant Hepatic Failure in Albino Rats

Functional perturbation of mitochondria is associated with fulminant hepatic failure (FHF). d-Galactosamine/lipopolysaccharide (d-GalN/LPS)-induced FHF is a renowned model to evaluate the efficacy of hepatoprotective agents. Lycopene is an antioxidant and phytonutrient from the carotenoid family. The health benefits of lycopene are prominent against cancer and cardiovascular, lung, liver, and skin problems. Recent studies have demonstrated the hepatoprotective, antidyslipidemic, and antioxidant roles of lycopene. The current study was designed to appraise the ability of lycopene to prevent mitochondrial dysfunction during the d-GalN/LPS-induced FHF. The administration of d-GalN/LPS (300 mg and 30 μg/kg body weight, respectively) to the experimental rats induced several disturbances in mitochondrial function. The lipid peroxide and hydrogen peroxide levels were increased (p < 0.05). The activities of mitochondrial antioxidants, tricarboxylic acid (TCA) cycle, and electron transport chain enzymes and the cellular adenosine triphosphate (ATP) content were decreased (p < 0.05). Lycopene (10 mg/kg body weight for 6 days) pretreatment attenuated lipid peroxidation and prohibited the excessive synthesis of hydrogen peroxide. The d-GalN/LPS-induced impairment in ATP production and increased enzyme activities were effectively prevented by the lycopene administration. The lycopene-mediated mitochondrial protection was mainly ascribed to the strong antioxidant potential of this phytonutrient. Molecular modeling results obtained show evidence that lycopene inhibits several lipoxygenases and provides rationale for the observed prevention of lipid peroxidation in the mitochondrial membrane. The carotenoid lycopene combatted oxidative stress, scavenged free radicals, prevented ROS generation, and inhibited the toxic effects of d-GalN/LPS during FHF.

Galangin, a natural flavonoid reduces mitochondrial oxidative damage in streptozotocin-induced diabetic rats

Objective: We designed this study to observe the effect of galangin on damaged mitochondria in the liver of diabetic rats.

Methods: Male albino Wistar rats were made diabetic by injecting streptozotocin (STZ) intraperitoneally (40 mg kg⁻¹ body weight (BW)). Galangin (8 mg kg⁻¹ BW) or glibenclamide (600 µg kg⁻¹ BW) was given orally daily once for 45 days to both healthy and diabetic rats.

Results: Diabetic rats showed significant (P < 0.05) increase in liver mitochondrial oxidant [Thiobarbituric acid reactive substance (TBARS)] level and a significant decrease in enzymatic [superoxide dismutase (SOD), glutathione peroxidase (GPx)] and non-enzymatic (reduced glutathione (GSH)) antioxidant levels when compared with healthy rats. The mitochondrial enzymes isocitrate dehydrogenase (ICDH), alpha-ketoglutarate dehydrogenase (α-KGDH), succinate dehydrogenase (SDH) and malate dehydrogenase (MDH) and mitochondrial respiratory chain enzymes NADH-dehydrogenase and Cytochrome c-oxidase were decreased significantly (P < 0.05) in diabetic rats when compared with healthy rats. A natural flavonoid galangin administered to hyperglycemia-induced rats resulted in the following findings as compared to hyperglycemia-induced control rats: the oxidant levels decreased significantly (P < 0.05); the enzymatic and non-enzymatic antioxidant levels increased significantly (P < 0.05) and the function of mitochondrial enzymes and the mitochondrial respiratory chain enzymes increased significantly (P < 0.05).

Conclusion: From the results, we conclude that galangin could maintain liver mitochondrial function in diabetic rats.

Metabolic adaptability in hexavalent chromium-treated renal tissue: an in vivo study

Background

Hexavalent chromium [Cr(VI)], an environmental pollutant that originates mostly from anthropogenic sources, is a serious threat to human health. After entering into cells, Cr(VI) is capable of producing excessive free radicals and causing tissue damage. The present study aims to reveal the toxic manifestation of Cr(VI) on the metabolic activity of renal tissue.

Methods

Male Swiss albino mice were treated orally with potassium dichromate (K₂Cr₂O₇) at a dose of 10 mg/kg body weight for a period of 30 days. Important tricarboxylic acid (TCA) cycle enzyme activities like isocitrate dehydrogenase, succinate dehydrogenase and malate dehydrogenase, as well as the activities of enzymes involved in oxidative phosphorylation such as Nicotinamide adenine dinucleotide (NADH) dehydrogenase, were measured. Additionally, transaminase and protease (pronase, cathepsin and trypsin) activities, tissue protein and free amino nitrogen were estimated in renal tissue. Glucose-6-phosphatase, glucose-6-phosphate dehydrogenase and alkaline phosphatase activities, as well as lactic acid, pyruvic acid and chromium contents, of kidneys were determined following standard protocols. Kidney histology was performed by hematoxylin and eosin staining.

Results

Cr(VI) suppresses the rate-limiting enzymes of the TCA cycle and oxidative phosphorylation indicating an inhibition of renal ATP production. It decreases protease activity by eliminating the protein substrates and alters the gluconeogenic pathway. Cr(VI) worsens the normophysiological attributes of renal tissue by enhancing the activity of alkaline phosphatase, pointing towards kidney disease. Histopathological observations confirmed these biochemical results through the presence of chronic tubular nephritis and altered glomerular structure. Cr(VI) retention occurs to a greater extent in renal tissue, which intensifies the toxic manifestation of this pollutant in the kidney.

Conclusions

Cr(VI) disrupts the metabolic interaction between carbohydrates and proteins in mammalian renal tissue.

New amino acid-Schiff base derived from s-allyl cysteine and methionine alleviates carbon tetrachloride-induced liver dysfunction

In spite of the tremendous stride in modern medicine, conventional drugs used in the hepatotoxic management are mostly inadequate. The present study aims in the synthesis of novel Schiff base compound derived using s-allyl cystiene and methionine. The newly synthesized compound, 2-((2-((2-(allylthio)-1-carboxyethyl)imino)ethylidene)amino)-4-(methylthio)butanoic acid (ACEMB) was characterized using UV-visible spectrophotometer, FTIR, ¹HNMR, and GC-MS. ACEMB showed potent in vitro antioxidant property. Chronic administration of ACEMB prior to CCl₄ intoxication: i) attenuated the leakage of liver injury markers, such as, enzymes (AST, ALT, GGT, ALP and LDH) and biomolecules (bilirubin) into the blood circulation; ii) normalized the concentration of total proteins, albumin and globulin to control level; and iii) protected the liver against dyslipidemia. These effects of ACEMB show the preservation of endoplasmic reticulum function against CCl₄ toxicity in the liver. The protective effect of ACEMB was due to its antioxidant property, which was revealed by reduced oxidative stress (TBARS and HP) and enhanced functions of the endogenous antioxidative system (SOD, catalase, GPx, GST, GSH, vitamin E and C) against CCl₄ intoxication. Also, ACEMB protected the functional activities of the various mitochondrial tricarboxylic acid cycle and oxidative phosphorylation enzymes. The biochemical alterations are in concurrence with the histological observations, wherein ACEMB pretreatment prevented the vacuolation, degeneration of nuclei and necrosis of hepatocytes. In addition, in silico analysis reveals the interaction of ACEMB in the active site of cytochrome P450. ACEMB mediates hepatoprotective effect by substituting itself as an antioxidant and decreasing oxidative stress, thereby diminishing the intracellular organelle dysfunction against CCl₄ toxicity in the liver.

Beneficial influence of ellagic acid on biochemical indexes associated with experimentally induced colon carcinogenesis

OBJECTIVE

To elucidate the key biochemical indexes associated with 1, 2-dimethylhydrazine (DMH)-induced colon carcinogenesis and the modulatory efficacy of a dietary polyphenol, ellagic acid (EA).

MATERIALS AND METHODS

Wistar rats were chosen to study objective, and were divided into 4 groups; Group 1-control rats; Group 2-rats received EA (60 mg/kg body weight/day, orally); rats in Group 3-induced with DMH (20 mg/kg body weight) subcutaneously for 15 weeks; DMH-induced Group 4 rats were initiated with EA treatment. We examined key citric acid cycle enzymes such as isocitrate dehydrogenase, alpha-ketoglutarate dehydrogenase, succinate dehydrogenase, malate dehydrogenase and the activities of respiratory chain enzymes NADH dehydrogenase and Cytochrome-C-oxidase and membrane-bound enzyme profiles (Na +/K + ATPase, Ca 2+ ATPase and Mg 2+ ATPase), activities of lysosomal proteases such as β-D-glucuronidase, β-galactosidase and N-acety-β-D-glucosaminidase and cellular thiols (oxidized glutathione, protein thiols, and total thiols).

RESULTS

It was found that administration of DMH to rats decreased both mitochondrial and membrane-bound enzymes activities, increased activities of lysosomal enzymes and further modulates cellular thiols levels. Treatment with EA significantly restored the mitochondrial and ATPases levels and further reduced lysosomal enzymes to near normalcy thereby restoring harmful effects induced by DMH.

CONCLUSION

EA treatment was able to effectively restore the detrimental effects induced by DMH, which proves the chemoprotective function of EA against DMH-induced experimental colon carcinogenesis.

Ameliorating effect of Kalpaamruthaa on altered energy metabolism in BCR-ABL+ cell line induced leukemic mouse model

OBJECTIVE

To evaluate the protective effect of Kalpaamruthaa (KA), a modified Siddha preparation, in BCR-ABL+ leukemic mouse model.

METHODS

BCR-ABL leukemia was induced in 6-10-week-old female BALB/c mice by a single tail vein injection of the 12B1 cell line. Leukemia-induced animals were treated with KA at a dosage of 200 mg/kg body weight dissolved in 0.5 mL of olive oil for 14 days by gastrogavage. Imatinib mesylate was used as the control drug. Glycolytic, gluconeogenic, mitochondrial, tricarboxylic acid cycle and respiratory chain enzymes in the spleen and liver of mouse were compared between the control and experiment groups by biochemical assays.

RESULTS

Leukemia-bearing mice showed a significant increase in glycolytic enzymes and a signififi cant decrease in gluconeogenic enzymes, tricarboxylic acid cycle and respiratory chain enzymes as compared with control animals. Treatment with KA signififi cantly reversed the changes seen in the levels of the glycolytic enzymes, gluconeogenic enzymes and mitochondrial enzymes.

CONCLUSION

The presence of various flfl avonoids and polyphenols in the drug KA might have resulted in the amelioration of altered glucose metabolism resulting in the regression of leukemia.

Rotenone causing dysfunctional mitochondria and lysosomes in cerebral ganglions of Lumbricus terrestris degenerate giant fibers and neuromuscular junctions

Rotenone is well-documented to cause neurodegenerative condition such as Parkinson's, in the exposed systems. However, its detrimental effect on particular sites of neuronal pathway is still under investigation. We aimed at elucidating the impact of rotenone on cerebral ganglions (CG) of Lumbricus terrestris which control movement and behaviour of the worms. Worms were exposed to 0-0.4 ppm/mL of rotenone. Mitochondrial and lysosomal integrities were found to be affected beyond 0.2 ppm/mL of rotenone. Activities of cholinergic enzymes and the expression of tyrosine hydroxylase showed an impaired neuronal transmission in CGs at the dose of 0.2 ppm/mL of rotenone. Histopathological and immunoflourescent analyses showed neuronal apoptosis, reduced nucleic acid content and inhibited of neurosecretion at 0.3 ppm/mL. Electron microscopy showed that the neurons and neuromuscular junctions were affected at 0.2 ppm/mL. Dose-dependent changes were also observed in the motor function such as burrowing behaviours and locomotion. Conduction velocity (CV) and locomotion assessment showed that the CV of lateral giant fiber (LGF) was reduced while that of MGF remains unaffected at 0.2 ppm, the dose at which the burrowing behaviour was also not affected. LGF, cholinergic enzymes and tyrosine hydroxylase are primarily targeted by rotenone affecting locomotion at 0.2 ppm/mL while MGF, neuropile and the burrowing behaviour were affected at 0.3 ppm/mL. We demonstrate, in addition to dose-dependent effects, that the bioaccumulation factors range 0.28-0.32 ppm/μg of rotenone cause degenerative impact on giant fibers affecting neuronal behaviors/locomotion of worms. We also propose worms for studying mechanisms of neuronal pathology caused by chemicals prevailing in earth's atmosphere.

Assessment of hepatoprotective and nephroprotective potential of withaferin A on bromobenzene-induced injury in Swiss albino mice: possible involvement of mitochondrial dysfunction and inflammation

Bromobenzene is a well-known environmental toxin which causes liver and kidney damage through CYP450-mediated bio-activation to generate reactive metabolites and, consequently, oxidative stress. The present study aimed to evaluate the possible protective role of withaferin A against bromobenzene-induced liver and kidney damage in mice. Withaferin A (10 mg/kg) was administered orally to the mice for 8 days before intragastric intubation of bromobenzene (10 mmol/kg). As results of this experiment, the levels of liver and kidney functional markers, lipid peroxidation, and cytokines (TNF-α and IL-1β) presented an increase and there was a decrease in anti-oxidant activity in the bromobenzene-treated group of mice. Pre-treatment with withaferin A not only significantly decreased the levels of liver and kidney functional markers and cytokines but also reduced oxidative stress, as evidenced by improved anti-oxidant status. In addition, the mitochondrial dysfunction shown through the decrease in the activities of mitochondrial enzymes and imbalance in the Bax/Bcl-2 expression in the livers and kidneys of bromobenzene-treated mice was effectively prevented by pre-administration of withaferin A. These results validated our conviction that bromobenzene caused liver and kidney damage via mitochondrial pathway and withaferin A provided significant protection against it. Thus, withaferin A may have possible usage in clinical liver and kidney diseases in which oxidative stress and mitochondrial dysfunction may be existent.

Exploring the Potential Role of Chemopreventive Agent, Hesperetin Conjugated Pegylated Gold Nanoparticles in Diethylnitrosamine-Induced Hepatocellular Carcinoma in Male Wistar Albino Rats

Liver cancer is the fifth most common cancer and is still one of the leading causes of death world wide, due to food additives, alcohol, fungal toxins, air, toxic industrial chemicals, and water pollutants. Chemopreventive drugs play a potential role in liver cancer treatment. Obviously in the production of anticancer drugs, the factors like poor solubility, bioavailability, biocompatibility, limited chemical stability, large amount of dose etc., plays a major role. Against this backdrop, the idea of designing the chemopreventive nature of bio flavanoid hesperetin (HP) drug conjugated with pegylated gold nanoparticles to increasing the solubility, improve bioavailability and enhance the targeting capabilities of the drug during diethylnitrosamine (DEN) induced liver cancer in male wistar albino rats. The dose fixation studies and the toxicity of pure HP and HP conjugated gold nanoparticles (Au-mPEG(5000)-S-HP) were analysed. After concluded the dose fixation and toxicity studies the experimental design were segregated in six groups for the anticancer analysis of DEN induced HCC for 16 weeks. After the experimental period the body weight, relative liver weight, number of nodules and size of nodules, the levels of tumor markers like CEA, AFP and the level of lipid peroxidation, lipid hydroperoxides and the activities of antioxidant enzymes were assessed. The administration of DEN to rats resulted in increased relative liver weight and serum marker enzymes aspartate transaminase, alanine transaminase, alkaline phosphatase, lactate dehydrogenase, and gamma glutamyl transpeptidase. The levels of lipid peroxides elevated (in both serum and tissue) with subsequent decrease in the final body weight and tissue antioxidants like superoxide dismutase, catalase, reduced glutathione, glutathione peroxidise, and glutathione reductase. HP supplementation (20 mg/kg b.wt) significantly attenuated these alterations, thereby showing potent anticancer effect in liver cancer and the HP loaded gold nanoparticels (Au-mPEG(5000)-S-HP) treated animals shows the better treatment than the pure HP due to the solubility of drug, bioavailability and the target drug delivery of the biodegradable polymer. Histological observations were also carried out, which added supports to the chemopreventive action of the pure HP and HP loaded gold nanoparticles (Au-mPEG(5000)-S-HP) against DEN induction during liver cancer progression. These findings suggest that HP loaded gold nanoparticels (Au-mPEG(5000)-S-HP) shows better efficacy than the pure HP against lipid peroxidation, hepatic cell damage and protects the antioxidant system in DEN induced hepatocellular carcinogenesis.

Preventive effects of zingerone on cardiac mitochondrial oxidative stress, calcium ion overload and adenosine triphosphate depletion in isoproterenol induced myocardial infarcted rats

Cardiac mitochondrial oxidative stress, calcium ion (Ca²⁺) overload and adenosine triphosphate (ATP) depletion play an important role in the pathogenesis of myocardial infarction.

RETRACTED: Cadmium induced cardiac oxidative stress in rats and its attenuation by GSP through the activation of Nrf2 signaling pathway

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. Western Blots from Figures 8B and 9A appear similar to Blots from Figure 4A of the article previously published by the authors in Biochemistry and Cell Biology 93 (2015) 210-226 https://doi.org/10.1139/bcb-2014-0114 and Figures 12 and 14 of the article previously published by the corresponding author et al in Biomedicine & Preventive Nutrition 4 (2014) 561-577 https://doi.org/10.1016/j.bionut.2014.08.003, although the Western Blots purportedly described different samples. Also, sections within the panels from Figures 10 and 11D appear unusually similar to each other. The explanation provided by the corresponding author was not satisfactory and the Editor decided to retract the article.

Hepatoprotective effect of grape seed proanthocyanidins on Cadmium-induced hepatic injury in rats: Possible involvement of mitochondrial dysfunction, inflammation and apoptosis

The present study was undertaken to evaluate the possible ameliorative role of grape seed proanthocyanidins (GSP) against Cadmium (Cd) induced hepatic inflammation, apoptosis and hepatic mitochondrial toxicity in rats. Male Wistar rats were distributed in four experimental groups: control, GSP, Cd and Cd + GSP. Exposure to a hepatotoxic dose of Cd (5 mg/kg BW) caused liver damage, coupled with enhanced reactive oxygen species (ROS) generation, increased inflammation and apoptosis in liver with increased DNA damage in hepatocytes of rats. Mitochondria were isolated from the hepatic tissues of rats from each group. Our results showed significant decrease in the tri-carboxylic acid cycle enzymes, increased mitochondrial swelling, inhibition of cytochrome c oxidase activity and complex I-III, II-III and IV mediated electron transfer, decreased mitochondrial ATPases, a reduction in calcium content and mitochondrial oxygen consumption in Cd treated rats. All these molecular changes caused by Cd were alleviated by the pre-supplementation with GSP (100 mg/kg BW). The ultra structural changes in the liver also support our findings. From our results, it is clearly indicated that the free radical scavenging, metal chelating and antioxidant potentials of GSP might be the possible reason, responsible for the rescue action against Cd induced mitochondrial damage in the liver of rats.

Oxidation of NADH and ROS production by respiratory complex I

Kinetic characteristics of the proton-pumping NADH:quinone reductases (respiratory complexes I) are reviewed. Unsolved problems of the redox-linked proton translocation activities are outlined. The parameters of complex I-mediated superoxide/hydrogen peroxide generation are summarized, and the physiological significance of mitochondrial ROS production is discussed. This article is part of a Special Issue entitled Respiratory complex I, edited by Volker Zickermann and Ulrich Brandt.

Effect of Solanum surattense on mitochondrial enzymes in diabetic rats and in vitro glucose uptake activity in L6 myotubes

BACKGROUND

S. surattense is widely used in Siddha medicine for various ailments.

OBJECTIVE

The aim was to evaluate the impact of alcoholic leaf-extract of S. surattense on mitochondrial enzymes in streptozotocin (STZ) induced diabetic rats and to study the in vitro muscle glucose uptake activity on L6 myotubes.

MATERIALS AND METHODS

The male albino Wistar rats were randomly divided into five groups of six animals each. Diabetes was induced by intraperitoneal injection of STZ (40 mg/kg body weight). After being confirmed the diabetic rats were treated with alcoholic leaf-extract of S. surattense (100 mg/kg body weight) for 45 days. The biochemical estimations (liver mitochondrial enzymes, antioxidants, thiobarbituric acid reactive substances [TBARS]) and histopathological studies were performed. Further, the in vitro muscle glucose uptake activity in L6 myotubes and messenger RNA (mRNA) expression of glucose transporter-4 (GLUT-4) was performed.

RESULTS

In diabetic rats, the activities of liver mitochondrial enzymes were found to be significantly lowered. The mitochondrial TBARS level increased, whereas the activities/level of enzymatic and non-enzymatic antioxidants decreased in diabetic rats. Administration of S. surattense to diabetic rats significantly reversed the above parameters toward normalcy. Furthermore in diabetic rats, the histopathological studies showed growth of adipose tissue and shrinkage of islets in the pancreas, liver showed fatty change with mild inflammation of portal triad, and kidney showed messangial capillary proliferation of glomeruli and fatty infiltration of tubules. Treatment with S. surattense brought back these changes to near normalcy. The extract was analyzed for in vitro muscle glucose uptake activity in L6 myotubes and mRNA expression of GLUT-4 by semi-quantitative reverse transcriptase-polymerase chain reaction. One nano gram per millilitre of S. surattense leaf-extract gave 115% glucose uptake on L6 myotubes. It also showed elevated levels of GLUT-4 mRNA transcripts, when compared with control cells.

CONCLUSION

These studies strongly support the anti-diabetic nature of S. surattense.

Luteolin, a bioflavonoid, attenuates azoxymethane-induced effects on mitochondrial enzymes in BALB/c mice

Colon cancer (CRC) is a serious health problem throughout the world. Development of novel drugs without side effects for this cancer is crucial. Luteolin (LUT), a bioflavonoid, has many beneficial effects such as antioxidant, anti-inflammatory and anti-proliferative potential. was a potent chemical carcinogen used for the induction of colon cancer. Colon carcinogenesis was initiated by intraperitoneal injection of azoxymethane (AOM) to mice at the dose of 15 mg/body kg weight in Balb/C mice for 3 weeks. Mice were treated with LUT at the dose of 1.2 mg /body kg weight orally. Mitochondrial enzymes such as isocitrate dehydrogenase (ICDH), α-keto dehydrogenase (α-KDH), succinate dehydrogenase (SDH) and the activities of respiratory chain enzymes NADH dehydrogenase and cytochrome c oxidase were found to be elevated in AOM-treated animals. Treatment with LUT decreased the activities of all the parameters significantly. Hence, LUT might be a potent anticancer agent against colorectal cancer.

Epigallocatechin gallate potentially attenuates Fluoride induced oxidative stress mediated cardiotoxicity and dyslipidemia in rats

The present study was undertaken to evaluate the cardioprotective role of (-)-epigallocatechin-gallate (EGCG) against Fluoride (F) induced oxidative stress mediated cardiotoxicity in rats. The animals exposed to F as sodium Fluoride (NaF) (25mg/kg BW) for 4 weeks exhibited a significant increase in the levels of cardiac troponins T and I (cTnT & I), cardiac serum markers, lipid peroxidative markers and plasma total cholesterol (TC), triglycerides (TG), phospholipids (PL), free fatty acids (FFA), low density lipoprotein cholesterol, very low density lipoprotein cholesterol as well as cardiac lipids profile (TC, TG and FFA) with the significant decrease of high density lipoprotein cholesterol and cardiac phospholipids. F intoxication also decreased the levels of mitochondrial enzymes such as ICDH, SDH, MDH, α-KGDH and NADH in the cardiac tissue of rats. The mitochondrial Ca(2+) ion level was also significantly reduced along with the significant decrease in the levels of enzymatic and non enzymatic antioxidants. Furthermore, F treatment significantly increased the DNA fragmentation, up regulate cardiac pro-apoptotic markers, inflammatory markers and down-regulate the anti-apoptotic markers in the cardiac tissue. Pre administration of EGCG (40mg/kg/bw) in F intoxicated rats remarkably recovered all these altered parameters to near normalcy through its antioxidant nature. Thus, results of the present study clearly demonstrated that treatment with EGCG prior to F intoxication has a significant role in protecting F-induced cardiotoxicity and dyslipidemia in rats.

Silibinin potentially attenuates arsenic-induced oxidative stress mediated cardiotoxicity and dyslipidemia in rats

Cardiac dysfunction is one of the major causes of mortality and morbidity throughout the world. Chronic exposure of arsenic (As) mainly leads to cardiotoxic effect. Cardiotoxicity was induced by the sodium arsenite as the source of As (5 mg/kg BW, PO) for 4 weeks. As intoxication significantly (p < 0.05) increased the serum cardiac markers, viz. creatine kinase-MB, lactate dehydrogenase, aspartate transaminase, alanine transaminase and alkaline phosphatase, oxidative stress markers in heart, plasma total cholesterol (TC), triglycerides (TG), phospholipids (PL), free fatty acids (FFA), low density lipoprotein cholesterol, very low density lipoprotein cholesterol as well as cardiac lipid profile (TC, TG and FFA) and significantly (p < 0.05) decreased the level of serum high density lipoprotein cholesterol, cardiac PL, mitochondrial enzymes such as ICDH, SDH, MDH, α-KDH and NADH dehydrogenase, levels of enzymatic antioxidant, nonenzymatic antioxidants and membrane-bound ATPases in heart. In addition, As-intoxicated rats showed a significant (p < 0.05) up-regulation of myocardial NADPH (NOX) oxidase sub units such as NOX2 and NOX4 as well as Keap-1 and down-regulation of Nrf2 and HO-1 protein expressions. Pre-administration of silibinin (SB) (75 mg/kg BW) remarkably recovered all these altered parameters to near normalcy in As-induced cardiotoxic rat. Moreover, the light microscopic and transmission electron microscopic study further supports the protective efficacy of SB on the heart mitochondria. In conclusion, our data demonstrate that SB has a potential to extenuate the arsenic-induced cardiotoxicity and dyslipidemia in rat.

Arsenic-induced hepatic mitochondrial toxicity in rats and its amelioration by diallyl trisulfide

The present investigation was aimed to investigate the possible protective role of diallyl trisulfide (DATS) against arsenic (As)-induced hepatic mitochondrial toxicity in rats. Mitochondria were isolated from the liver tissue of rats from all the groups. Lipid profile, lipid peroxidation, antioxidant enzyme activities, hepatic function enzymes, mitochondrial swelling, cytochrome c oxidase activity, mitochondrial Ca(+)-ATPase and Na(+)/K(+)-ATPase activity, mitochondrial calcium content and mitochondrial enzyme activities were measured. Short-term As exposure (5 mg/kg bw/d for 28 d) caused liver damage as evidenced by changes in activities of liver enzymes. The effects of As were coupled with enhanced reactive oxygen species generation, mitochondrial swelling, inhibition of cytochrome c oxidase, complex I-mediated electron transfer, decreased Ca(2+)-ATPase and Na(+)/K(+)-ATPase activity, a reduction in mitochondrial calcium content, changes in indices of hepatic mitochondrial oxidative stress, significant increase in mitochondrial lipid peroxidation products and alterations in mitochondrial lipid profile. Significant decreases in mitochondrial antioxidants and tricarboxylic acid cycle enzymes were also found in the liver mitochondria of As-induced hepatic mitochondrial toxicity in rats. As also increased hepatic caspase-3 activity and DNA fragmentation. All these apoptosis-related molecular changes caused by As could be alleviated by supplementation with DATS, which likely suggests a protective role against As-induced hepatotoxic changes and hepatic mitochondrial toxicity. The protective effect of DATS on the liver mitochondria was evidenced by altering all the changes induced by As. Free radical scavenging and metal chelating activities of DATS may be the mechanism, responsible for the protective action against As-induced mitochondrial damage in liver.

Amelioration of bromobenzene hepatotoxicity by Withania somnifera pretreatment: Role of mitochondrial oxidative stress

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Administration of bromobenzene to rats caused increased levels of liver marker enzymes, lipid peroxidation, TNF-α, IL-1β, VEGF, depletion in levels of mitochondrial enzymes and antioxidants.

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Pre-treatment with Withania somnifera normalized the levels of liver marker enzymes, TNF-α, IL-1β, VEGF, mitochondrial enzymes, antioxidants and ameliorated histopathological manifestations in bromobenzene-treated rats.

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Molecular dockings studies showed strong interactions between pro-inflammatory mediator NF-ƙB and various active components of W. somnifera (Withaferin A, Withanolide D and Withanolide E), thus blocking it from causing progressive tissue damage.

The present study investigated the possible protective role of Withania somnifera (Linn.) Dunal (Solanaceae) root powder against bromobenzene-induced oxidative damage in rat liver mitochondria. Administration of bromobenzene (10 mmol/kg body weight) to rats resulted in increased levels of liver marker enzymes, lipid peroxidation, TNF-α, IL-1β and VEGF. There was also marked depletion in the levels of mitochondrial enzymes and antioxidant activity. Pre-treatment with W. somnifera significantly decreased the levels of liver marker enzymes, TNF-α, IL-1β, VEGF and ameliorated histopathological manifestations in bromobenzene-treated rats. The molecular docking analysis predicted that the pro-inflammatory mediator NF-κB showed significant interaction with selected various active components of W. somnifera (withaferin A, withanolide D and withanolide E). This study demonstrates a good protective effect of W. somnifera against bromobenzene-induced oxidative stress.

(-)-Epigallocatechin-gallate (EGCG) stabilize the mitochondrial enzymes and inhibits the apoptosis in cigarette smoke-induced myocardial dysfunction in rats

The present study brings out the preventive role of (-)-epigallocatechin-gallate (EGCG) on cardiac mitochondrial metabolism and apoptosis in cigarette smoke (CS)-exposed rats. The CS-exposed rats showed significantly decreased activities of TCA cycle enzymes and mitochondrial enzymatic antioxidants, on the other hand, mitochondrial lipid peroxidation was increased and GSH level was decreased. Further, CS exposure was found to induce cardiac apoptosis through release of cytochrome c into the cytosol, cleavage of pro-caspase-3 to active caspase-3, up-regulation of pro-apoptotic (Bax) and down-regulation of antiapoptotic (Bcl-2) molecules. The CS-induced apoptosis was further confirmed by mitochondrial and nuclear ultra structural apoptotic features as evaluated by electron microscopic studies. EGCG supplementation shelters the activities of TCA cycle enzymes and antioxidant enzymes, with concomitant decrease in lipid peroxidation and increase in GSH level. EGCG administration inhibited apoptosis through the inhibition of cytochrome c release into cytosol, activation of pro-caspase-3, down regulation of Bax and significant up regulation of Bcl-2. EGCG reversed the ultra structural apoptotic alterations of mitochondria and nucleus. The present study has provided experimental evidences that the EGCG treatment enduring to cardio protection at mitochondrial level.

Mitigating role of baicalein on lysosomal enzymes and xenobiotic metabolizing enzyme status during lung carcinogenesis of Swiss albino mice induced by benzo(a)pyrene

The lungs mainly serve as a primary site for xenobiotic metabolism and constitute an important defense mechanism against inhalation of carcinogens. Our current study aimed to evaluate the chemotherapeutic efficacy of baicalein (BE) in Swiss albino mice exposed to tobacco-specific carcinogen benzo(a)pyrene [B(a)P] for its ability to mitigate pulmonary carcinogenesis. Here, we report that altered activities/levels of lysosomal enzymes (cathepsin-D, cathepsin-B, acid phosphatase, β-D-galactosidase, β-D-glucuronidase, and β-D-N-acetyl glucosaminidase), phase I biotransformation enzymes (cytochrome P450, cytochrome b5, NADPH-cytochrome P450 reductase, and NADH-cytochrome b5 reductase), and phase II enzymes (glutathione S-transferase, UDP-glucuronyl transferase, and DT-diaphorase) were observed in the B(a)P-induced mice. Treatment with BE significantly restored back the activities/levels of lysosomal enzymes, phase I and phase II biotransformation enzymes. Moreover, assessment of lysosomal abnormalities by transmission electron microscopic examination revealed that BE treatment effectively counteract B(a)P-induced oxidative damages. Protein expression levels studied by immunohistochemistry, immunofluorescence, and immunoblot analysis of CYP1A1 revealed that BE treatment effectively negate B(a)P-induced upregulated expression of CYP1A1. Further analysis of scanning electron microscopic studies in lung was carried out to substantiate the anticarcinogenic effect of BE. The overall data suggest that BE treatment significantly inhibits lysosomal and microsomal dysfunction, thus revealing its potent anticarcinogenic effect.

Baicalein abrogates reactive oxygen species (ROS)-mediated mitochondrial dysfunction during experimental pulmonary carcinogenesis in vivo

Our current study aimed to evaluate the chemotherapeutic efficacy of baicalein (BE) in Swiss albino mice, which is exposed to benzo(a)pyrene [B(a)P] for its ability to alleviate mitochondrial dysfunction and systolic failure. Here, we report that oral administration of B(a)P (50 mg/kg body weight)-induced pulmonary genotoxicities in mice was assessed in terms of elevation in reactive oxygen species (ROS) generation and DNA damage in lung mitochondria. MDA-DNA adducts were formed in immunohistochemical analysis, which confirmed nuclear DNA damage. mRNA expression levels studied by RT-PCR analysis of voltage-dependent anion channel (VDAC) and adenine nucleotide translocase (ANT) were found to be significantly decreased and showed a marked increase in membrane permeability transition pore (MPTP) opening. Accompanied by up-regulated Bcl-xL and down-regulated Bid, Bim and Cyt-c proteins studied by immunoblot were observed in B(a)P-induced lung cancer-bearing animals. Administration of BE (12 mg/kg body weight) significantly reversed all the above deleterious changes. Moreover, assessment of mitochondrial enzyme system revealed that BE treatment effectively counteracts B(a)P-induced down-regulated levels/activities of isocitrate dehydrogenase, α-ketoglutarate dehydrogenase, succinate dehydrogenase, malate dehydrogenase, NADH dehydrogenase, cytochrome-C-oxidase and ATP levels. Restoration of mitochondria from oxidative damage was further confirmed by transmission electron microscopic examination. Further analysis of lipid peroxidation, superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, glutathione reductase, reduced glutathione, vitamin E and vitamin C in lung mitochondria was carried out to substantiate the antioxidant effect of BE. The overall data conclude that chemotherapeutic efficacy of BE might have strong mitochondria protective and restoration capacity in sub-cellular level against lung carcinogenesis in Swiss albino mice.

(-) Epicatechin attenuates mitochondrial damage by enhancing mitochondrial multi-marker enzymes, adenosine triphosphate and lowering calcium in isoproterenol induced myocardial infarcted rats

Cardiac mitochondrial damage plays an important role in the pathology of myocardial infarction. The protective effects of (-) epicatechin on cardiac mitochondrial damage in isoproterenol induced myocardial infarction were evaluated in rats. Rats were pretreated with (-) epicatechin (20 mg/kg body weight) daily for a period of 21 days. After the pretreatment period, isoproterenol (100 mg/kg body weight) was injected subcutaneously into rats twice at an interval of 24 h to induce myocardial infarction. Isoproterenol induced myocardial infarcted rats showed a significant increase in the levels of cardiac diagnostic markers, heart mitochondrial lipid peroxidation, calcium, and a significant decrease in the activities/levels of heart mitochondrial glutathione peroxidase, glutathione reductase, reduced glutathione, isocitrate, succinate, malate, α-ketoglutarate and NADH-dehydrogenases, cytochrome-C-oxidase and adenosine triphosphate. (-) Epicatechin pretreatment showed significant protective effects on all the biochemical parameters evaluated. The in vitro study revealed the superoxide and hydroxyl radical scavenging activity of (-) epicatechin. The possible mechanisms for the beneficial effects of (-) epicatechin on cardiac mitochondria could be attributed to scavenging of free radicals, decreasing calcium, increasing multi-enzymes (antioxidant, tricarboxylic acid cycle and respiratory chain enzymes), reduced glutathione and adenosine triphosphate. Thus, (-) epicatechin attenuated mitochondrial damage in isoproterenol induced myocardial infarcted rats.

Mechanistic clues in the protective effect of ellagic acid against apoptosis and decreased mitochondrial respiratory enzyme activities in myocardial infarcted rats

Our previous study described the cardioprotective effects of ellagic acid in an isoproterenol-induced myocardial infarction model. In this study, we are reporting the mechanism of protective action of ellagic acid with respect to apoptosis and mitochondrial respiratory enzymes. Ellagic acid (7.5 and 15 mg/kg) was administered orally as a pretreatment for 10 days. Then, isoproterenol (100 mg/kg) was injected subcutaneously to rats at an interval of 24 h for 2 days. Myocardial infarction was quantified by planimetry. Apoptosis was measured by apoptotic gene expressions. The levels of mitochondrial respiratory enzymes were also measured. Isoproterenol-induced myocardial infarcted rats showed increased infarct size, a decrease in myocardial expression of the Bcl-2 gene and an increase in myocardial expression of the BAX gene. Fas ligand and caspases were markedly elevated along with compromised respiratory marker enzymes in isoproterenol-induced rats. Ellagic acid pretreatment reduced the infarct size, regulated apoptotic gene expressions and enhanced the activities of mitochondrial respiratory marker enzymes and cell viability, thereby protecting the myocardium against isoproterenol-induced myocardial infarction. The decreased infarct size associated with inhibited apoptosis and increased respiratory marker enzymes provide insight on the role of ellagic acid in antiapoptotic mechanism, and it may be the reason for its cardioprotective activity.

Protective effect of morin on cardiac mitochondrial function during isoproterenol-induced myocardial infarction in male Wistar rats

Altered mitochondrial function and free radical-mediated tissue damage have been suggested as an important pathological event in isoproterenol (ISO)-induced cardiotoxicity. This study was undertaken to know the preventive effect of morin on mitochondrial damage in ISO-induced cardiotoxicity in male Wistar rats. Myocardial infarction (MI) in rats was induced by ISO (85 mg/kg) at an interval of 24 hours for 2 days. Morin was given to rats as pre-treatment for 30 days orally using an intragastric tube. ISO-treated rats showed a significant elevation of mitochondrial thiobarbituric acid reactive substances (TBARS) and hydrogen peroxide (HP) level and pre-treatment with morin significantly prevented the increase of TBARS and HP level to near normality. The level of enzymic and non-enzymic antioxidants was decreased significantly in ISO-treated rats and pre-treatment with morin significantly increased the levels of superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, glutathione reductase, and reduced glutathione to normality. The activities of mitochondrial enzymes such as isocitrate dehydrogenase, alpha-ketoglutarate dehydrogenase, succinate dehydrogenase, and malate dehydrogenase were decreased significantly in ISO-treated myocardial ischemic rats and upon pre-treatment with morin restored these enzymes activity to normality. In addition, the decreased activities of cytochrome-C oxidase and NADH-dehydrogenases were observed in ISO-treated rats and pre-treatment with morin prevented the activities of cytochrome-C oxidase and NADH-dehydrogenase to normality. Pre-treatment with morin favorably restored the biochemical and functional parameters to near normal indicating morin to be a significant protective effect on cardiac mitochondrial function against ISO-induced MI in rats.

Lipoic acid mitigates bisphenol A-induced testicular mitochondrial toxicity in rats

Bisphenol A (BPA) is one of the highest volume chemicals produced worldwide. BPA is used in the production of polycarbonate plastics and epoxy resins used in manufacturing plastic baby bottles and lining of food cans. In this study, we investigated the BPA-induced testicular oxidative stress and perturbation of mitochondrial marker enzymes in male albino rats and its amelioration by α-lipoic acid (LA). Rats were administered a dose of BPA (10 mg/kg body weight) orally for 14 days. This resulted in decreased testes weight, total testicular protein content, testicular enzymes such as acid phosphatase, alkaline phosphatase and lactate dehydrogenase and decline in activities of marker mitochondrial enzymes such as succinate dehydrogenase, malate dehydrogenase, isocitrate dehydrogenase, monoamine oxidase and NADH dehydrogenase. The serum testosterone and total antioxidant status were reduced. Besides, it also affected the activities of testicular antioxidant enzymes such as glutathione reductase, glutathione peroxidase, superoxide dismutase and catalase. BPA also caused lipid peroxidation and decrease in reduced glutathione content of mitochondria. The co-administration of LA (20 mg/kg body weight; orally for 14 days) together with BPA resulted in restoration of the mitochondrial marker enzyme activities and increasing enzymatic and non-enzymatic antioxidants of mitochondria. The obtained results demonstrated that LA has a potential role in mitigating BPA-induced mitochondrial toxicity through antioxidant mechanism or by direct free radical scavenging activity.

Ameliorative effect of methanol extract of Rubia cordifolia in N-nitrosodiethylamine-induced hepatocellular carcinoma

CONTEXT

Rubia cordifolia Linn. (Rubiaceae) is a medicinal plant used in the ayurvedic system of medicine. It is also known as Indian Madder or Manjistha and is traditionally used as an antiinflammatory, antiseptic, and galactopurifier, but its anticancer propertis are yet not known.

OBJECTIVE

The ameliorative effect of the Rubia cordifolia methanol extract on N-nitrosodiethylamine-induced experimental hepatocellular carcinogenesis in rats.

MATERIALS AND METHODS

Changes in liver weight, serum markers of liver damage, hydroxyl radicals, lipid peroxidation, levels of enzymic and nonenzymic antioxidants; mitochondrial and respiratory chain enzymes were also investigated using various biochemical parameters and histopathological studies. Male albino rats of Wistar strain were divided into four groups for a study period of 3 months. Animals of group I and group IV served as control and drug control, respectively. Hepatocellular carcinoma was induced in animals of groups II and III with 0.02% N-nitrosodiethylamine.

RESULTS

Upon Rubia cordifolia methanol extract co-treatment (250, 500, and 750 mg/kg bodyweight) in group III alone levels of serum marker enzymes and antioxidants increased significantly in a dose-dependent manner. The levels of hydroxyl radicals and lipid peroxidation decreased. Mitochondrial enzymes and respiratory chain enzymes, which were decreased in N-nitrosodiethylamine-induced rats, increased significantly in RC treated rats. Further histological analysis of liver confirmed the prevention of pathological changes caused by N-nitrosodiethylamine on Rubia cordifolia supplementation.

DISCUSSION AND CONCLUSION

These findings demonstrate that Rubia cordifolia can be a source of potent antioxidants for treatment of diseases such as cancer.