Rat Liver Mitochondria Research Articles

Comparing the Effect of Grape Fermentative Product and Fresh Red Grape Juice on Antioxidant Biomarkers of Liver Mitochondria Isolated From Rats in Vitro

Background: Mitochondria are a source of reactive oxygen species (ROS), and several natural compounds are used as antioxidant agents. This study aimed to investigate and compare the effects of fresh grape juice red wine on oxidative stress biomarkers in rat liver mitochondria. Materials and Methods: In this regard, mitochondria were isolated from the liver of 27 male Wistar rats (220-250 g). The isolated mitochondria were cultured in different doses of red wine and fresh red grape juice for 24, 48, and 72 h. After treatment, total antioxidant capacity, lipid peroxidation, total thiol groups, and catalase activity were determined in the isolated mitochondria of the rat liver. Results: The results confirmed the oxidant/antioxidant effects of red wine and fresh red grape juice at different times. Conclusion: According to the results, the fresh red grape juice showed higher antioxidant properties than red wine in the liver mitochondrial samples.

The mitochondria-targeted derivative of the classical uncoupler of oxidative phosphorylation carbonyl cyanide m-chlorophenylhydrazone is an effective mitochondrial recoupler.

The synthesis of a mitochondria-targeted derivative of the classical mitochondrial uncoupler carbonyl cyanide-m-chlorophenylhydrazone (CCCP) by alkoxy substitution of CCCP with n-decyl(triphenyl)phosphonium cation yielded mitoCCCP, which was able to inhibit the uncoupling action of CCCP, tyrphostin A9 and niclosamide on rat liver mitochondria, but not that of 2,4-dinitrophenol, at a concentration of 1-2 μM. MitoCCCP did not uncouple mitochondria by itself at these concentrations, although it exhibited uncoupling action at tens of micromolar concentrations. Thus, mitoCCCP appeared to be a more effective mitochondrial recoupler than 6-ketocholestanol. Both mitoCCCP and 6-ketocholestanol did not inhibit the protonophoric activity of CCCP in artificial bilayer lipid membranes, which might compromise the simple proton-shuttling mechanism of the uncoupling activity on mitochondria.

<p><strong>Edible mushroom <em>Morchella esculenta</em> (L.) Pers. mycelium protects DNA and mitochondria from radiation induced damages</strong></p>

Mushrooms have gained great attraction not only for their nutritional and medicinal values but also for diversity of their bioactive components. Morchella esculenta, commonly called Morel, is an edible and nutritious mushroom. In the present study, we evaluated the radioprotective effect of cultured mycelium of M. esculenta against radiation induced damages in mouse spleen lymphocyte DNA and rat liver mitochondria. The mitochondria were exposed to 450 Gy g-radiation and lipid peroxidation caused by radiation was studied by LOOH assay and TBARS assay. M. esculenta extract at a concentration of 200 and 50 µg/mL significantly inhibited the formation of LOOH and TBARS formation in mitochondria. The protective effect of M. esculenta against radiation-induced damage to DNA in the spleen lymphocyte was measured using comet assay. Spleen lymphocytes were exposed to γ-radiation at a dose of 6 Gy in the presence and absence of the extract and the strand break were analyzed. The extract inhibited the strand break significantly. The study indicate that M. esculenta mycelia protect mitochondria form oxidative stress and DNA from deleterious effects induced by radiation and has potential for the development of safe and non-toxic radio protector with significant nutritional properties.

Functional activity of permeability transition pore in energized and deenergized rat liver mitochondria

Functional activity of permeability transition pore in energized and deenergized rat liver mitochondria

State of the antioxidant protection system of rat liver in ischemia and reperfusion

Purpose: determination of the state of the antioxidant protection system of the cytosolic fraction and suspension of rat liver mitochondria after experimental ischemia and reperfusion. Materials and methods: the study was conducted using white mature rats, divided into 3 groups: the control group (n = 15); The 2nd group of animals (n = 15), from which the liver was taken after 15 minutes of liver ischemia; the 3rd group of rats (n = 15), from which the liver was taken after a 15-minute reperfusion period, followed by a 15-minute ischemic period. Mitochondrial suspension and cytosolic fraction were isolated from liver tissue. Results: the obtained research results showed the presence of certain pathobiochemical changes in the suspension of mitochondria and the cytosolic fraction after ischemia or reperfusion. In the mitochondrial suspension during the reperfusion period it was found an adaptive increase in the activity of glutathione peroxidase by 39% and glutathione reductase by 61%. In the cytosolic fraction, it was the most remarkable increase of the total antioxidant capacity by 38% already during ischemia and a progressive decrease in the level of reduced glutathione form by 26% in ischemic and 55% in reperfusion period. The change in the state of the antioxidant system occurred against the background of an increase in the number of products of oxidative modifications of biomolecules by 40% during ischemia and 2.2 times after reperfusion. Conclusion: The results indicate the need to develop not only a mitochondria-oriented correction of oxidative disorders, but also active support for the components of the cytosol, which provide the main accumulation of free radical damage products and their subsequent removal from the cell, which is essential for survival.

Співвідношення редокс-форм убіхінону в мітохондріях печінки щурів за умов різної забезпеченості раціону нутрієнтами

The relationship between the quantitative ratio of redox forms of ubiquinone and the degree of free radical damage to mitochondrial proteins in rat liver against the background of nutritional imbalance was investigated. The animals were divided into the following experimental groups: I – animals receiving full-value semi-synthetic ration (control group); II – animals receiving high-sucrose diet; III – animals receiving low-protein high-sucrose diet. The content of total and oxidized ubiquinone was determined spectrophotometrically at 275 nm, the content of reduced ubiquinone was determined by the difference between the content of total and oxidized ubiquinone. The intensity of the oxidative modification of proteins was assessed by the accumulation of carbonyl derivatives in the reaction with 2,4-dinitrophenylhydrazine (2,4-DNPH), the content of free SH-groups was assessed by using the Elman reagent. It was found that the most pronounced decrease in the content of total ubiquinone (almost twice) and the redistribution of its redox forms (reduction of the content of reduced ubiquinone by 7.2 times against the background of an increase in the level of oxidized ubiquinone by 2 times) in rat liver mitochondria is observed in animals that received a diet high in sucrose against the background of alimentary protein deprivation. In addition, the animals of this group showed the most pronounced free radical oxidation of mitochondrial proteins, as evidenced by a 3.5-fold increase in the content of carbonyl derivatives and a 2.6-fold decrease in the content of free protein SH- groups. It was shown that nutritional protein deficiency is a critical factor affecting the intensity of free radical processes in mitochondria. The established changes in the ratio of the redox forms of ubiquinone and the degree of oxidative modification of mitochondrial proteins in rat liver could be considered as prerequisites for deepening the energy imbalance and violation of the functional activity of mitochondria under conditions of nutritional imbalance.

Bisindolylpyrrole triggers transient mitochondrial permeability transitions to cause apoptosis in a VDAC1/2 and cyclophilin D-dependent manner via the ANT-associated pore

Bisindolylpyrrole at 0.1 μM is cytoprotective in 2% FBS that is counteracted by cyclosporin-A (CsA), an inhibitor of cyclophilin-D (CypD). We hypothesized that the cytoprotective effect might be due to transient mitochondrial permeability transition (tPT). This study tested the hypothesis that bisindolylpyrrole can trigger tPT extensively, thereby leading to cell death under certain conditions. Indeed, CsA-sensitive tPT-mediated apoptosis could be induced by bisindolylpyrrole at > 5 μM in HeLa cells cultured in 0.1% FBS, depending on CypD and VDAC1/2, as shown by siRNA knockdown experiments. Rat liver mitochondria also underwent swelling in response to bisindolylpyrrole, which proceeded at a slower rate than Ca2+-induced swelling, and which was blocked by the VDAC inhibitor tubulin and the ANT inhibitor bongkrekate, indicating the involvement of the ANT-associated, smaller pore. We examined why 0.1% FBS is a prerequisite for apoptosis and found that apoptosis is blocked by PKC activation, which is counteracted by the overexpressed defective PKCε. In mitochondrial suspensions, bisindolylpyrrole triggered CsA-sensitive swelling, which was suppressed selectively by pretreatment with PKCε, but not in the co-presence of tubulin. These data suggest that upon PKC inactivation the cytoprotective compound bisindolylpyrrole can induce prolonged tPT causing apoptosis in a CypD-dependent manner through the VDAC1/2-regulated ANT-associated pore.

Protonophoric action of BAM15 on planar bilayers, liposomes, mitochondria, bacteria and neurons

Small molecules capable of uncoupling respiration and ATP synthesis in mitochondria are protective towards various cell malfunctions. Recently (2-fluorophenyl){6-[(2-fluorophenyl)amino](1,2,5-oxadiazolo[3,4-e]pyrazin-5-yl)}amine (BAM15), a new compound of this type, has become popular as a potent mitochondria-selective depolarizing agent producing minimal adverse effects. To validate protonophoric mechanism of BAM15 action, we examined its behavior in bilayer lipid membranes (BLM). BAM15 proved to be a typical anionic protonophore with the activity on planar membranes being suppressed upon decreasing membrane dipole potential. In both planar BLM and liposomes, BAM15 induced proton conductance with the potency close to that of the classical protonophoric uncoupler carbonyl cyanide m-chlorophenyl hydrazone (CCCP). In isolated rat liver mitochondria (RLM), BAM15 caused membrane potential collapse, increased respiration rate and induced Ca2+ efflux at concentrations slightly higher than those for CCCP. Surprisingly, the uncoupling action of BAM15 on isolated RLM, in contrast to that of CCCP, was partially reversed by carboxyatractyloside (CATR), an inhibitor of adenine nucleotide translocase, thereby indicating involvement of this protein in the BAM15-induced uncoupling. BAM15 inhibited growth of Bacillus subtilis at micromolar concentrations. In electrophysiological experiments on molluscan neurons, BAM15 caused plasma membrane depolarization and suppression of electrical activity, but the effect developed more slowly than that of CCCP.

Diazinon impairs bioenergetics and induces membrane permeability transition on mitochondria isolated from rat liver

ABSTRACT Diazinon (DZN) is a broad-spectrum insecticide extensively used to control pests in crops and animals. Several investigators demonstrated that DZN produced tissue toxicity especially to the liver. In addition, the mitochondrion was implicated in DZN-induced toxicity, but the precise role of this organelle remains to be determined. The aim of this study was thus to examine the effects of DZN (50 to 150 μM) on the bioenergetics and mitochondrial permeability transition (MPT) associated processes in isolated rat liver mitochondria. DZN inhibited state-3 respiration in mitochondria energized with glutamate plus malate, substrates of complex I, and succinate, substrate of complex II of the respiratory chain and decreased the mitochondrial membrane potential resulting in inhibition of ATP synthesis. MPT was estimated by the extent of mitochondrial swelling, in the presence of 10 µM Ca2+. DZN elicited MPT in a concentration-dependent manner, via a mechanism sensitive to cyclosporine A, EGTA, ruthenium red and N-ethylmaleimide, which was associated with mitochondrial Ca2+ efflux and cytochrome c release. DZN did not result in hydrogen peroxide accumulation or glutathione oxidation, but this insecticide oxidized endogenous NAD(P)H and protein thiol groups. Data suggest the involvement of mitochondria, via apoptosis, in the hepatic cytotoxicity attributed to DZN.

The Effects of PK11195 and Protoporphyrin IX Can Modulate Chronic Alcohol Intoxication in Rat Liver Mitochondria under the Opening of the Mitochondrial Permeability Transition Pore.

Decades of active research have shown that mitochondrial dysfunction, the associated oxidative stress, impaired anti-stress defense mechanisms, and the activation of the proapoptotic signaling pathways underlie pathological changes in organs and tissues. Pathologies caused by alcohol primarily affect the liver. Alcohol abuse is the cause of many liver diseases, such as steatosis, alcoholic steatohepatitis, fibrosis, cirrhosis, and, potentially, hepatocellular cancer. In this study, the effect of chronic alcohol exposure on rat liver mitochondria was investigated. We observed an ethanol-induced increase in sensitivity to calcium, changes in the level of protein kinase Akt and GSK-3β phosphorylation, an induction of the mitochondrial permeability transition pore (mPTP), and strong alterations in the expression of mPTP regulators. Moreover, we also showed an enhanced effect of PK11195 and PPIX, on the parameters of the mPTP opening in rat liver mitochondria (RLM) isolated from ethanol-treated rats compared to the RLM from control rats. We suggest that the results of this study could help elucidate the mechanisms of chronic ethanol action on the mitochondria and contribute to the development of new therapeutic strategies for treating the effects of ethanol-related diseases.

Effect of betulin and betulonic acid on isolated rat liver mitochondria and liposomes

The paper considers the effects of plant triterpenoid betulin and its derivative betulonic acid on rat liver mitochondria and liposomes. It was found that betulonic acid and, to a lesser extent, betulin, activate mitochondrial respiration in states 2 and 4 and inhibit ADP- and DNP-stimulated (uncoupled) respiration. The effect of betulonic acid resulted in a significant decrease of the respiratory control and ADP/O ratios and decrease in Δψ. The effects of both compounds were most pronounced in the case of succinate-fueled mitochondrial respiration. This may include both the possible protonophore effect of betulonic acid and the inhibition of respiratory chain complexes by both compounds. Both agents enhanced H2O2 production in succinate-fueled mitochondria, while betulonic acid exerted an antioxidant effect with NAD-dependent substrates. Betulin was found to induce mitochondrial aggregation, but had no effect on membrane permeability. A similar pattern was found on liposomes. As revealed by the laurdan generalized polarization (GP) technique, betulin increased laurdan GP in lecithin liposomes, indicating a decrease in membrane fluidity. Measurements of GP as a function of fluorescence excitation wavelength gave an ascending line for high concentrations of betulin, which can be interpreted as phase heterogeneity of the lipid/betulin system. High concentrations of betulin (> 60 mol%) was also demonstrated to cause permeabilization of lecithin liposomes. Betulonic acid was much less effective in inducing the aggregation of mitochondria and liposomes and had no effect on membrane permeability. The possible mechanisms of betulin and betulonic acid effect on rat liver mitochondria and liposomes are discussed.

Structural and Functional Features of Ca2+ Transport Systems in Liver Mitochondria of Rats with Experimental Hyperthyroidism.

We analyzed structural and functional features of the main mitochondrial Ca2+-transporting systems, mitochondrial Ca2+ uniporter complex (MCUC) and Ca2+-dependent cyclosporin A-sensitive mitochondrial permeability transition pore (MPT pore), in rats with hyperthyroid state. It was found that, the rate of Ca2+ accumulation by rat liver mitochondria in this pathology increases by 1.3 times, which can be associated with higher level of the channel-forming subunit of the uniporter MCU and lower content of dominant-negative subunit of this complex MCUb. At the same time, the level of the regulatory subunit MICU1 remained unchanged. It was shown that calcium retention capacity of liver mitochondria in rats with experimental hyperthyroidism decreased by 2 times in comparison with the control, which attested to reduced resistance of liver mitochondria of hyperthyroid rats to induction of the MPT pore. The observed changes are consistent with the data on increased amount of cyclophilin D, a mitochondrial matrix peptidyl-prolyl isomerase that is known to modulate the MPT pore opening and expression of the Ppif gene that encodes mitochondrial cyclophilin D in rats with experimental hyperthyroidism.

A facile synthesis of silver nanowires and their evaluation in the mitochondrial membrane potential.

Silver nanowires (AgNWs) with a high-aspect-ratio were successfully synthesized by a green method using Lavandula angustifolia plant extract. The morphology of the AgNWs was evaluated as a function of the concentration of precursor salt and nucleating agent. Furthermore, AgNWs were analyzed in a biological model using rat liver mitochondria by measuring their effect on membrane potential. The scanning electron microscopy (SEM), X-ray diffraction (XRD), and transmission electron microscopy (TEM) techniques structurally characterized the nanowires obtained. Also, ultraviolet-visible spectroscopy (UV-Vis) investigated the optical properties of AgNWs. Structural studies show AgNWs fcc with lengths up to 100μm and diameters ranging from 60 to 130nm growing in the [110] orientation. Both the CuSO4 nucleating agent and the centrifugation process are essential for the growth of nanowires. Furthermore, inhibition of mitochondrial membrane potential (MMP) depends on the concentration of the nanowires (NWs), suggesting dissipation of the electron transport chain. In this way, AgNWs can be used as a potential tool to verify biological reactions, such as modulation of metabolic pathways, together with the evaluation of a possible influence of biotic or abiotic factors in organisms.

Diazoxide affects mitochondrial bioenergetics by the opening of mKATP channel on submicromolar scale

BackgroundCytoprotection afforded by mitochondrial ATP-sensitive K+-channel (mKATP-channel) opener diazoxide (DZ) largely depends on the activation of potassium cycle with eventual modulation of mitochondrial functions and ROS production. However, generally these effects were studied in the presence of Mg∙ATP known to block K+ transport. Thus, the purpose of our work was the estimation of DZ effects on K+ transport, K+ cycle and ROS production in rat liver mitochondria in the absence of Mg∙ATP.ResultsWithout Mg·ATP, full activation of native mKATP-channel, accompanied by the increase in ATP-insensitive K+ uptake, activation of K+-cycle and respiratory uncoupling, was reached at ≤0.5 μM of DZ,. Higher diazoxide concentrations augmented ATP-insensitive K+ uptake, but not mKATP-channel activity. mKATP-channel was blocked by Mg·ATP, reactivated by DZ, and repeatedly blocked by mKATP-channel blockers glibenclamide and 5-hydroxydecanoate, whereas ATP-insensitive potassium transport was blocked by Mg2+ and was not restored by DZ. High sensitivity of potassium transport to DZ in native mitochondria resulted in suppression of mitochondrial ROS production caused by the activation of K+-cycle on sub-micromolar scale. Based on the oxygen consumption study, the share of mKATP-channel in respiratory uncoupling by DZ was found.ConclusionsThe study of mKATP-channel activation by diazoxide in the absence of MgATP discloses novel, not described earlier, aspects of mKATP-channel interaction with this drug. High sensitivity of mKATP-channel to DZ results in the modulation of mitochondrial functions and ROS production by DZ on sub-micromolar concentration scale. Our experiments led us to the hypothesis that under the conditions marked by ATP deficiency affinity of mKATP-channel to DZ can increase, which might contribute to the high effectiveness of this drug in cardio- and neuroprotection.

Physiological Role of Glutamate Dehydrogenase in Cancer Cells.

increased growth rates and final densities of several human metastatic cancer cells. To assess whether glutamate dehydrogenase (GDH) in cancer cells may catalyze the reverse reaction of fixation, its covalent regulation and kinetic parameters were determined under near-physiological conditions. Increased total protein and phosphorylation were attained in -supplemented metastatic cells, but total cell GDH activity was unchanged. Higher Vmax values for the GDH reverse reaction vs. forward reaction in both isolated hepatoma (HepM) and liver mitochondria [rat liver mitochondria (RLM)] favored an -fixing role. GDH sigmoidal kinetics with , ADP, and leucine fitted to Hill equation showed nH values of 2 to 3. However, the K0.5 values for were over 20 mM, questioning the physiological relevance of the GDH reverse reaction, because intracellular in tumors is 1 to 5 mM. In contrast, data fitting to the Monod–Wyman–Changeux (MWC) model revealed lower Km values for , of 6 to 12 mM. In silico analysis made with MWC equation, and using physiological concentrations of substrates and modulators, predicted GDH N-fixing activity in cancer cells. Therefore, together with its thermodynamic feasibility, GDH may reach rates for its reverse, -fixing reaction that are compatible with an anabolic role for supporting growth of cancer cells.

Modulatory Effects of Ethyl Acetate and Methanol Fractions of the Stem Bark Extract of Alstonia boonei on Mitochondrial-Mediated Apoptosis

ABSTRACT Methanol and ethyl acetate fractions (MF and EF, respectively) of Alstonia boonei stem bark were investigated for their mitochondrial-mediated apoptosis in rat liver mitochondria. With Ca2+, EF potentiated the Ca2+-induced mitochondrial membrane permeability transition (MMPT) pore opening with induction fold of 2, 3, 4, and 5 at 10, 20, 40, and 80 µg mL−1, respectively, while the MF reversed Ca2+-induced MMPT pore at the same concentrations. Both MF and EF inhibited the lipid peroxidation. The EF enhanced mitochondrial ATPase activity, cytochrome c release, and caspase 3 and 9 activities. Terpenes were the most abundant natural products in EF. EF has bioactive agents that can modulate mitochondrial-mediated apoptosis.

A High Resolution Mass Spectrometry Study Reveals the Potential of Disulfide Formation in Human Mitochondrial Voltage-Dependent Anion Selective Channel Isoforms (hVDACs).

The voltage-dependent anion-selective channels (VDACs), which are also known as eukaryotic porins, are pore-forming proteins, which allow for the passage of ions and small molecules across the outer mitochondrial membrane (OMM). They are involved in complex interactions that regulate organelle and cellular metabolism. We have recently reported the post-translational modifications (PTMs) of the three VDAC isoforms purified from rat liver mitochondria (rVDACs), showing, for the first time, the over-oxidation of the cysteine residues as an exclusive feature of VDACs. Noteworthy, this peculiar PTM is not detectable in other integral membrane mitochondrial proteins, as defined by their elution at low salt concentration by a hydroxyapatite column. In this study, the association of tryptic and chymotryptic proteolysis with UHPLC/High Resolution nESI-MS/MS, allowed for us to extend the investigation to the human VDACs. The over-oxidation of the cysteine residues, essentially irreversible in cell conditions, was as also certained in VDAC isoforms from human cells. In human VDAC2 and 3 isoforms the permanently reduced state of a cluster of close cysteines indicates the possibility that disulfide bridges are formed in the proteins. Importantly, the detailed oxidative PTMs that are found in human VDACs confirm and sustain our previous findings in rat tissues, claiming for a predictable characterization that has to be conveyed in the functional role of VDAC proteins within the cell. Data are available via ProteomeXchange with identifier PXD017482.

Effect of Copper on the Mitochondrial Carnitine/Acylcarnitine Carrier Via Interaction with Cys136 and Cys155. Possible Implications in Pathophysiology.

The effect of copper on the mitochondrial carnitine/acylcarnitine carrier (CAC) was studied. Transport function was assayed as [3H]carnitine/carnitine antiport in proteoliposomes reconstituted with the native protein extracted from rat liver mitochondria or with the recombinant CAC over-expressed in E. coli. Cu2+ (as well as Cu+) strongly inhibited the native transporter. The inhibition was reversed by GSH (reduced glutathione) or by DTE (dithioerythritol). Dose-response analysis of the inhibition of the native protein was performed from which an IC50 of 1.6 µM for Cu2+ was derived. The mechanism of inhibition was studied by using the recombinant WT or Cys site-directed mutants of CAC. From the dose-response curve of the effect of Cu2+ on the recombinant protein, an IC50 of 0.28 µM was derived. Inhibition kinetics revealed a non-competitive type of inhibition by Cu2+. However, a substrate protection experiment indicated that the interaction of Cu2+ with the protein occurred in the vicinity of the substrate-binding site. Dose-response analysis on Cys mutants led to much higher IC50 values for the mutants C136S or C155S. The highest value was obtained for the C136/155S double mutant, indicating the involvement of both Cys residues in the interaction with Cu2+. Computational analysis performed on the WT CAC and on Cys mutants showed a pattern of the binding energy mostly overlapping the binding affinity derived from the dose-response analysis. All the data concur with bridging of Cu2+ with the two Cys residues, which blocks the conformational changes required for transport cycle.

A combination extract of kaffir lime, galangal, and lemongrass maintains blood lipid profiles, hepatocytes, and liver mitochondria in rats with nonalcoholic steatohepatitis

Kaffir lime leaves and the rhizomes of galangal and lemongrass are the main ingredients in several Thai foods with desirable medicinal effects. Based on their beneficial activities, this study aimed to indicate the chemical properties and in vivo efficacy of a combination of the herbs at a 1:2:1 ratio in a water extract form. Its volatile constituents were analyzed by gas chromatography coupled with mass spectrometer, which mainly consists of eucalyptol, citronellal, and citral. Clinicohistopathological and electron microscopic studies demonstrated that the extract corrected blood cholesterol, LDL, HDL, and triglyceride levels similarly as simvastatin treatment in association with its antioxidative properties, as indicated by the levels of superoxide dismutase and malondialdehyde in serum and the increment of nuclear factor erythroid 2-related factor 2 levels in hepatocytes. Hepatitis was significantly less severe in rats fed the extract for 14 days than in simvastatin-treated rats. Regarding its immunomodulatory properties, the extract also accelerated hepatic resolution from steatohepatitis during hypercholesterolemia as indicated by the upregulation of vimentin, cytokeratin, and CD206+. Interestingly, liver mitochondria were also preserved in hypercholesterolemic rats treated with the extract in relation to their architecture and the expression of haloacid dehalogenase-like hydrolase domain-containing protein 3 as well as metabolic and energy regulators. Therefore, the study concluded that the water extract of kaffir lime leaves and the rhizomes of galangal and lemongrass has beneficial effects on blood cholesterol, the severity of steatohepatitis, and the maintenance of mitochondrial architecture via its antioxidative and immunomodulatory activities.

Aged garlic extract and its constituent, S-allyl-L-cysteine, induce the apoptosis of neuroblastoma cancer cells due to mitochondrial membrane depolarization.

Aged garlic extract (AGE) has been demonstrated to have therapeutic properties in tumors; however its mechanisms of action have not yet been fully elucidated. A previous study revealed that AGE exerts an anti-proliferative effect on a panel of both sensitive [wild-type (WT)] and multidrug-resistant (MDR) human cancer cells. Following treatment of the cells with AGE, cytofluorimetric analysis revealed the occurrence of dose-dependent mitochondrial membrane depolarization (MMD). In this study, in order to further clarify the mechanisms of action of AGE, the effects of AGE on mitochondria isolated from rat liver mitochondria (RLM) were also examined. AGE induced an effect on the components of the electrochemical gradient (ΔµH+), mitochondrial membrane potential (ΔΨm) and mitochondrial electrochemical gradient (ΔpHm). The mitochondrial membrane dysfunctions of RLM induced by AGE, namely the decrease in both membrane potential and chemical gradient were associated with a higher oxidation of both the endogenous glutathione and pyridine nucleotide content. To confirm the anti-proliferative effects of AGE, experiments were performed on the human neuroblastoma (NB) cancer cells, SJ-N-KP and the MYCN-amplified IMR5 cells, using its derivative S-allyl-L-cysteine (SAC), with the aim of providing evidence of the anticancer activity of this compound and its possible molecular mechanism as regards the induction of cytotoxicity. Following treatment of the cells with SAC at 20 mM, cell viability was determined by MTT assay and apoptosis was detected by flow cytometry, using Annexin V-FITC labeling. The percentages of cells undergoing apoptosis was found to be 48.0% in the SJ-N-KP and 50.1% in the IMR5 cells. By cytofluorimetric analysis, it was suggested that the target of SAC are the mitochondria. Mitochondrial activity was examined by labeling the cells with the probe, 5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethylimidacarbocyanine iodide (JC-1). Following treatment with SAC at 50 mM, both NB cell lines exhibited a marked increase in MMD. On the whole, the findings of this study indicate that both natural products, AGE and SAC, cause cytotoxicity to tumor cells via the induction of mitochondrial permeability transition (MPT).