Atractylenolide III induces apoptosis by regulating the Bax/Bcl-2 signaling pathway in human colorectal cancer HCT-116 Cells in vitro and in vivo.

Atractylodes is the dry root of atractylodes macrocephala koidz and has been commonly used as a traditional Chinese medicine (TCM). Atractylenolide III, a main component of atractylodes, has displayed significant effects on anti-inflammation and anticancer. However, the effects of atractylenolide III on growth inhibition and apoptosis induction in colon cancer remain unclear. The results showed that atractylenolide III significantly inhibited the cell growth and induce cellular apoptosis in HCT-116 cells in a concentration dependence manner in vitro. Mechanistic studies further showed that atractylenolide III could regulate the Bax/Bcl-2 apoptotic signaling pathway through promoting the expression of proapoptotic related gene/proteins Bax, caspase-9 and caspase-3 but inhibiting the expression of antiapoptotic related gene/protein Bcl-2 in HCT-116 cells. Furthermore, atractylenolide III also significantly inhibited the tumor growth of HCT-116 tumor xenografts bearing in nude mice through inducing apoptosis by upregulation of the expressions of Bax, cleaved caspase-3 and p53 but downregulation of the expressions of Bcl-2 in HCT-116 tumor tissues in vivo. The studies may provide the scientific rationale for the understanding of the anticancer effect of atractylenolide III. Therefore, atractylenolide III may have the potential to be developed as a promising novel anticancer agent for the treatment of colorectal cancer clinically.

The effects of L-carnitine on renal function and gene expression of caspase-9 and Bcl-2 in monosodium glutamate-induced rats.

BACKGROUND: Monosodium glutamate (MSG) is frequently consumed as a flavor enhancer or food additive. Possible damages induced by MSG effects on some organs have been stated in experimental animal models. The aim of the present study was to evaluate the protective effects of L-carnitine (L-ca) on the renal tissue in MSG-Induced Rats. METHODS: In this regard, 60 male rats were randomly divided into six groups (n = 10/each): 1 (Control); 2 (sham); 3 (L-carnitine 200 mg/kg b.w); 4 (MSG 3 g/kg b.w); 5 (MSG + L-carnitine 100 mg/kg); and 6 (MSG + L-carnitine 200 mg/kg). After 6 months, the rats were sacrificed, the blood sample collected and the kidneys harvested for evaluation of biochemical analytes, genes expression, and histopathological changes. RESULTS: MSG significantly increased the serum level of MDA, BUN, creatinine, uric acid and renal Caspase-9, NGAL and KIM-1 expression, but it decreased the serum activity also renal expression of SOD, catalase, GPX, and Bcl-2 expression compared to the control group. Treatment with L-ca significantly reduced the serum BUN, creatinine, uric acid and MDA level and increased catalase, GPX and SOD compared to the MSG group. However, only administration of L-ca 200 significantly decreased the caspase-9, NGAL and KIM-1; also, it increased the Bcl-2 expression in the kidney compared to the MSG group. CONCLUSIONS: Our findings indicated that L-carnitine had a major impact on the cell protection and might be an effective therapy in ameliorating the complications of the kidney induced by MSG via its antioxidant and anti-apoptotic properties.

Murrayanine Induces Cell Cycle Arrest, Oxidative Stress, and Inhibition of Phosphorylated p38 Expression in A549 Lung Adenocarcinoma Cells.

BACKGROUND Murrayanine is a carbazole alkaloid derived from Murraya koenigii, which has been used in traditional Chinese medicine in the treatment of cancer. This study aimed to investigate the effects of murrayanine on human lung adenocarcinoma cells in vitro and to investigate the mechanisms of its action. MATERIAL AND METHODS A549 human lung adenocarcinoma cells and MRC-5 human lung fibroblasts were grown in culture, and an MTT assay determined cell viability. Cells were treated for 24 h with increasing doses of murrayanine (0, 9, 18, and 36 µM). Fluorescence, using 4', 6-diamidino-2-phenylindole (DAPI), acridine orange, ethidium bromide, and propidium iodide (PI), were used for the detection of apoptosis. The cell cycle was studied with fluorescence-activated cell sorting (FACS), and Western blot evaluated protein expression. RESULTS Murrayanine treatment resulted in significant dose-dependent inhibition of the growth of A549 cells (p<0.05), with an IC50 of 9 µM, and arrested the cells at the G2/M phase of the cell cycle, reduced the expression of cyclin D and E, CDK2, 4, and 6, and increased the expression of p21 and p27. Murrayanine treatment increased apoptosis of the A549 cells and increased cleaved of caspase-3 and caspase-9, and the Bax/Bcl-2 ratio. Murrayanine treatment increased levels of reactive oxygen species (ROS), disrupted the mitochondrial membrane potential, inhibited invasion, and inhibited phosphorylation of p38 mitogen-activated protein kinase (MAPK) of the A549 cells. CONCLUSIONS Murrayanine induced cell cycle arrest, oxidative stress, and inhibited the expression of phosphorylated p38 in A549 adenocarcinoma cells.

Radix Tetrastigma Hemsleyani Flavone Suppresses Cutaneous Squamous Cell Carcinoma A431 Cells via Proteasome Inhibition.

BACKGROUND Radix Tetrastigma Hemsleyani Flavone (RTHF) has detoxification and anti- inflammation activity and is widely used. Here, we report that RTHF inhibits cell proliferation and induces apoptosis in cutaneous squamous cell carcinoma A431 cells and is a potential strategy for cancer therapy. MATERIAL AND METHODS A431 cells were cultured in different concentrations of RTHF. The inhibition of cell proliferation was assessed by MTT assay, cell apoptosis was shown through FCM, and cell invasion was assessed by Transwell methods. Enzyme proteasome assay was used to detect the activity of proteasome and DUB. Expression of apoptosis-related and ubiquitin proteasome pathway-associated proteins were assessed by PCR and Western blot. RESULTS RTHF obviously suppressed the proliferation and induced apoptosis of A431 cells in a dose-dependent manner. Transwell assay showed that RTHF inhibited the cell metastasis significantly. Enzyme proteasome assay show that the RTHF treatment of activity of proteasome and DUB was significantly lower than in control. RTHF increased the expression of Bax and inhibited Bcl-2, pro-caspase3, and pro-caspase9 activity. The expression of USP14, UCHL5, and POH1 decreased and ub-prs increased significantly in the treatment group. CONCLUSIONS Our study reveals that RTHF-mediated inhibition of DUBs and proteasome may provide a potential strategy for cancer therapy.

[Role of green tea polyphenols in noise-induced hearing loss].

Objective: To investigate the role and mechanism of action of green tea polyphenols in noise-induced hearing loss. Methods: Male specific pathogen-free guinea pigs were randomly divided into normal control group with 9 guinea pigs, noise exposure group with 36 guinea pigs, and green tea polyphenol intervention group with 36 guinea pigs. Auditory brainstem response (ABR) threshold shift was examined before noise exposure and at 1, 3, 7, and 14 days of noise exposure. The surface preparation of cochlear basilar membrane was used for hair cell count and the morphology of hair cells was also observed. Western blot was used to observe the expression of cysteinyl aspartate-specific protease-9 (caspase-9) and cysteinyl aspartate-specific protease-3 (caspase-3) in cochlear tissue. Results: Both the noise exposure group and the green tea polyphenol intervention group had an increase in ABR threshold after noise exposure, and the green tea polyphenol intervention group had a significantly lower ABR threshold shift than the noise exposure group at all time points (P<0.05). Both groups had enlargement, atrophy, or loss of hair cells after noise exposure, and at 7 and 14 days of noise exposure, the noise exposure group had a significantly higher rate of abnormal hair cells than the green tea polyphenol intervention group (P<0.05). Both groups had an increase in the expression of caspase-9 and caspase-3 after noise exposure, and the noise exposure group had a significantly greater increase than the green tea polyphenol intervention group (P<0.05). Conclusion: Green tea polyphenols can reduce noise-induced hearing loss and hair cell injury, possibly by regulating the expression of caspase-9 and caspase-3.

Anticancer activity of Ashwagandha against human head and neck cancer cell lines.

BACKGROUND: The aim of this study was to determine the apoptotic activity of methanol extract of Ashwagandha (MEAG) and in human head and neck squamous cell carcinoma (HNSCC) cells and to investigate the underlying mechanisms. METHODS: We investigated the effects of MEAG on programmed cell death in HNSCC cells using a Live/Dead assay, detection of nuclear morphologic changes, Mitotracker, siRNA knockdown, and RT-PCR. RESULTS: Treatment with MEAG showed dose-dependent growth-inhibitory activity that attribute to caspase-dependent apoptosis. Loss of mitochondrial membrane potential, release of cytochrome c, and activation of caspase 9 suggested that MEAG leads to activation of mitochondria-mediated apoptosis. MEAG selectively upregulated the expression of Bim protein at the transcriptional level and induced the translocation of Bim into the mitochondria. Knockdown of Bim by siRNA partially blocked MEAG-mediated apoptosis. MEAG also caused an increase in truncated Bid (t-Bid), cleaved caspase-8, and death receptor 5 (DR5). Interestingly, withaferin A (WA), a bioactive component of MEAG, clearly induced apoptosis accompanied by upregulation of Bim, t-Bid, caspase-8, and DR5 similar to the effects of MEAG. CONCLUSIONS: These suggest that MEAG and WA may be potential natural materials for the treatment of HNSCC.

Lantana camara Induces Apoptosis by Bcl-2 Family and Caspases Activation.

Breast cancer is one of the most common cancers worldwide, and the second most fatal cancer in women after lung cancer. Because there are instances of cancer resistance to existing therapies, studies focused on the identification of novel therapeutic drugs are very important. In this study, we identified a natural anticancer agent from Lantana camara, a flowering plant species of the genus Verbena. The extract obtained from the L. camara exhibited cell death properties in the human breast cancer cell line, MCF-7. We found that the apoptosis induced by treatment with the L. camara extract was regulated by the Bcl-2 family. Bid and Bax was increased and Bcl-2 was decreased by L. camara extract. L. camara extract modulated cleavage of caspase-8, and caspase-9, as well as poly (ADP-ribose) polymerase (PARP). Our results support the potential use of the L. camara extract as an anti-breast cancer drug.

Effect of arecoline on regeneration of injured peripheral nerves.

The present study provides in vitro and in vivo evaluation of arecoline on peripheral nerve regeneration. In the in vitro study, we found that arecoline at 50 µg/ml could significantly promote the survival and outgrowth of cultured Schwann cells as compared to the controls treated with culture medium only. In the in vivo study, we evaluated peripheral nerve regeneration across a 10-mm gap in the sciatic nerve of the rat, using a silicone rubber nerve chamber filled with the arecoline solution. In the control group, the chambers were filled with normal saline only. At the end of the fourth week, morphometric data revealed that the arecoline-treated group at 5 µg/ml significantly increased the number and the density of myelinated axons as compared to the controls. Immunohistochemical staining in the arecoline-treated animals at 5 µg/ml also showed their neural cells in the L4 and L5 dorsal root ganglia ipsilateral to the injury were strongly retrograde-labeled with fluorogold and lamina I-II regions in the dorsal horn ipsilateral to the injury were significantly calcitonin gene-related peptide-immunolabeled compared with the controls. In addition, we found that the number of macrophages recruited in the distal sciatic nerve was increased as the concentration of arecoline was increased. Electrophysiological measurements showed the arecoline-treated groups at 5 and 50 µg/ml had a relatively larger nerve conductive velocity of the evoked muscle action potentials compared to the controls. These results indicate that arecoline could stimulate local inflammatory conditions, improving the recovery of a severe peripheral nerve injury.

Preferential inhibition of hepatocellular carcinoma by the flavonoid Baicalein through blocking MEK-ERK signaling.

Baicalein is a purified flavonoid extracted from the roots of Scutellaria baicalensis or Scutellaria radix. Although previous studies have suggested that Baicalein possesses an in vitro anti-hepatocellular carcinoma activity, its in vivo effects and mechanisms of action are still not completely understood. In this study, Baicalein at concentrations of 40-120 µM exhibited significant cytotoxicity to three hepatocellular carcinoma (HCC) cell lines but marginal cytotoxicity to a normal liver cell line in vitro. Compared to a standard chemotherapy drug, 5-fluorouracil (5-FU), Baicalein had greater effect on HCC cells but less toxicity on normal liver cells. Treatment with Baicalein dramatically reduced mitochondrial transmembrane potential, and activated caspase-9 and caspase-3. Blockade of Baicalein-induced apoptosis with a pan-caspase inhibitor partially attenuated Baicalein-induced growth inhibition in HCC. Baicalein treatment significantly inhibited tumor growth of HCC xenografts in mice. Induction of apoptosis was demonstrated in Baicalein-treated xenograft tumors by the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Furthermore, Baicalein treatment dramatically decreased the levels of phosphorylation of MEK1, ERK1/2 and Bad in vitro and in vivo. Overexpression of human MEK1 partially blocked Baicalein-induced growth inhibition. Consequently, these findings suggest that Baicalein preferentially inhibits HCC tumor growth through inhibition of MEK-ERK signaling and by inducing intrinsic apoptosis.

Lipid-soluble ginseng extract induces apoptosis and G0/G1 cell cycle arrest in NCI-H460 human lung cancer cells.

This study was performed to elucidate the anticancer mechanism of a lipid-soluble ginseng extract (LSGE) by analyzing induction of apoptosis and arrest of cell cycle progression using the NCI-H460 human lung cancer cell line. Proliferation of NCI-H460 cells was potently inhibited by LSGE in a dose-dependent manner. The cell cycle arrest at the G0/G1 phase in NCI-H460 cells was induced by LSGE. The percentage of G0/G1 phase cells significantly increased, while that of S phase cells decreased after treatment with LSGE. The expression levels of cyclin-dependent kinase2 (CDK2), CDK4, CDK6, cyclin D3 and cyclin E related to G0/G1 cells progression were also altered by LSGE. In addition, LSGE-induced cell death occurred through apoptosis, which was accompanied by increasing the activity of caspases including caspase-8, caspase-9 and caspase-3. Consistent with enhancement of caspase activity, LSGE increased protein levels of cleaved caspase-3, caspase-8, caspase-9, and poly-ADP-ribose polymerase (PARP). These apoptotic effects of LSGE were inhibited by the pan-caspase inhibitor Z-VAD-fmk. These findings indicate that LSGE inhibits NCI-H460 human lung cancer cell growth by cell cycle arrest at the G0/G1 phase and induction of caspase-mediated apoptosis.

Reduction in lipopolysaccharide-induced apoptosis of fibroblasts obtained from a patient with gingival overgrowth during nifedipine-treatment.

OBJECTIVE: We have previously demonstrated that the mechanism of nifedipine (NIF)-induced gingival overgrowth is related to the observation that proliferation and cell cycle progression of gingival fibroblasts derived from NIF reactive patient (NIFr) are greater than those from NIF non-reactive patient (NIFn). Gingival overgrowth has also been reported to be a result of inhibited apoptosis of gingival fibroblasts. Apoptosis in fibroblasts is induced by lipopolysaccharide (LPS). Thus, we focused upon evaluating whether there is a difference in LPS-induced apoptosis between NIFn and NIFr. METHODS: Both NIFn and NIFr were arrested in DMEM containing 0.5% FBS, stimulated by LPS, and assayed for apoptosis, cell cycle analysis, Western blotting, and caspase activity. RESULTS: Compared to NIFn, the number of apoptotic cells was significantly decreased and the percentage of cells in S and G(2)/M phase was significantly increased in NIFr. The levels of Bax and cytochrome c proteins in NIFr were not up-regulated by LPS compared with NIFn. Both NIFn and NIFr displayed the following changes in protein expression: increased Bad, decreased Bcl-xL, and unchanged Bcl-2 and p53. Caspase-3 and -9 activities were significantly increased by LPS in NIFn but were unchanged in NIFr. Caspase-2 activity remained constant whilst caspase-8 activity significantly increased upon LPS treatment in both NIFn and NIFr. CONCLUSION: Bad, Bax, cytochrome c, p53, and caspases-2, -3, -8, and -9 are pro-apoptotic proteins. Bcl-2 and Bcl-xL are anti-apoptotic proteins. Thus, the mechanism of NIF-induced gingival overgrowth might be related to decreased apoptosis in NIFr through a reduction of Bax, cytochrome c, and caspase-3 and -9.

Discovery and preclinical evaluation of a novel class of cytotoxic propynoic acid carbamoyl methyl amides (PACMAs).

Herein, we discovered a series of propynoic acid carbamoyl methyl-amides (PACMAs) with potent cytotoxicity against a panel of cancer cell lines. These compounds interrupted cell cycle progression at low micromolar concentrations and induced early and late stage apoptosis. A representative compound suppressed tumor growth without apparent toxicity in an MDA-MB-435 mouse xenograft model. We used a Kinexus 628-antibody microarray and the Ingenuity Pathway Analysis (IPA) bioinformatics tools to better understand their mechanisms. The IPA analysis revealed the initiation of Nrf2-mediated oxidative stress through modulating the expression of SOD1 and STIP1 by compound 1. The involvement of the oxidative stress pathway was further validated by measuring the levels of the PACMA-induced mitochondrial superoxide species. To our knowledge, this is the first report on the discovery and biological evaluations of PACMAs as anticancer agents. Their broad-spectrum in vitro cytotoxicity, possibly through an oxidative stress-mediated pathway, and in vivo efficacy warrant further preclinical investigations.

Typhonium flagelliforme induces apoptosis in CEMss cells via activation of caspase-9, PARP cleavage and cytochrome c release: its activation coupled with G0/G1 phase cell cycle arrest.

ETHNOPHARMACOLOGICAL RELEVANCE: The plant Typhonium flagelliforme (TF), commonly known as 'rodent tuber' in Malaysia, is often used as traditional remedy for cancer, including leukemia. AIM OF THE STUDY: We had previously identified morphologically that the linoleic acid rich fraction (DCM/F7) from the tubers of this plant induces selective anti-proliferative effects and apoptosis in CEMss cells. In this present study, we subjected the same DCM/F7 fraction to cell based activity analyses in order to determine the possible mechanism of cell death in leukemic CEMss cells in vitro. MATERIALS AND METHODS: Extraction of Typhonium flagelliforme tuber has done and fractionation has been done by vacuum liquid column chromatography. The anti-proliferative activity was assayed using MTT and the apoptosis detection was done by Annexin V and DNA laddering assay. Colorimetric caspase assay and immunoblot analysis were employed to detect the expression of protein associated with cell death. Cell cycle analysis was done using flow cytometry. RESULTS: We found that the cancer inhibitory effect of the DCM/F7 fraction in CEMss cells was 3 ± 0.08 µg/ml (IC(50)). An early apoptotic induction in CEMss cells was observed by Annexin V assay, which showed a clear dose-dependent DNA fragmentation being observed in gel electrophoresis at 10 and 20 µg/ml. The DCM/F7 fraction at 3 µg/ml significantly arrested CEMss cells at G0/G1 phase (p<0.05). A constant but increasing pattern-related Sub-G0/G1 index was observed between 12 and 72 h treatment. In relation to this, we further investigated the biochemical events leading to cell death and found that the DCM/F7 fraction increased the cellular levels of caspase-3 and -9 on treated cells. Our results indicated that cytochrome c from mitochondria into the cytosol increased gradually as the DCM/F7 concentration increases, which later lead to the subsequent cleavage of PARP in to 85kDa fragments. On the contrary, Bcl-2 protein was found to decrease concomitantly during treatment. CONCLUSIONS: Collectively, results presented in this study demonstrated that the DCM/F7 fraction inhibited the proliferation of leukemia cells, leading to the programmed cell death, which was confirmed to be through the mitochondrial pathway.

Catalpol protects primary cultured cortical neurons induced by Abeta(1-42) through a mitochondrial-dependent caspase pathway.

It has been reported that catalpol, an iridoid glucoside, isolated from the root of Rehmannia glutinosa, protected cells from damage induced by a variety of toxic stimulus such as LPS, MPP(+) and rotenone. Here, we further evaluated the effect of catalpol against Abeta(1-42)-induced apoptosis in primary cortical neuron cultures. In the present study, the primary cortical neuron culture treated with Abeta(1-42) was severed as cell model of Alzheimer's disease (AD) in vitro. By exposure to Abeta(1-42) (5 microM) for 72 h in cultures, neuronal apoptosis occurred characterized by enhancement of activities of caspases and reactive oxygen species (ROS) as well as Bax increase, loss of mitochondrial membrane potential and cytochrome c release. Pretreatment with catalpol (0.5mM) for 30 min prior to Abeta(1-42) treatment attenuated neuronal apoptosis not only by reversing intracellular ROS accumulation, Bax level, mitochondrial membrane potential and, cytochrome c release to some extent, but also through regulating the activity and cleavage of caspase-3 and caspase-9. Thus, catalpol protects primary cultured cortical neurons induced by Abeta(1-42) through a mitochondrial-dependent caspase pathway.

Cirsilineol inhibits proliferation of cancer cells by inducing apoptosis via mitochondrial pathway.

Cirsilineol (4',5-dihydroxy-3',6,7-trimethoxyflavone) is a compound isolated from the herb of Artemisia vestita Wall (Compositae). In this study, we aimed at examining the anti-proliferative activity of cirsilineol against multiple types of cancer cells and the underlying mechanisms. Cirsilineol significantly inhibited proliferation of Caov-3, Skov-3, PC3 and Hela cells in a concentration-dependent manner. The compound also dose-dependently induced apoptosis in Caov-3 cells, as determined by annexin V/propidium iodide staining. Besides, cirsilineol induced a remarkable change in mitochondrial membrane potential and caused release of cytochrome c to cytosol. Furthermore, the compound caused a marked activation of capase-3, caspase-9 and poly (ADP-ribose) polymerase (PARP). These results suggested that the induction of apoptosis via the mitochondrial pathway was involved in the anti-proliferative activity of cirsilineol against cancer cells.

Zinc inhibits ethanol-induced HepG2 cell apoptosis.

Alcohol consumption produces a variety of metabolic alterations in liver cells, associated with ethanol oxidation and with nonoxidative metabolism of ethanol, among others apoptosis of hepatocytes. As zinc is known as a potent antioxidant and an inhibitor of cell apoptosis, the aim of this paper was to investigate whether zinc supplementation could inhibit ethanol-induced HepG2 apoptosis, and whether this inhibition was connected with attenuation of oxidative stress and modulation of FasR/FasL system expression. The results indicated that zinc supplementation significantly inhibited ethanol-induced HepG2 cell apoptosis (measured by cytochrome c release from mitochondria and caspase-3 activation) by attenuation of reactive oxygen species (ROS) production, increase in the cellular level of GSH, inhibition of ethanol-induced sFasR and FasL overexpression and caspase-8 activation. These results indicate that zinc can inhibit ethanol-induced hepatocyte apoptosis by several independent mechanisms, among others by an indirect antioxidative effect and probably by inhibition of caspase-8 and caspase-9 activation.

Investigations of the cytotoxicity of epigallocatechin-3-gallate against PC-3 cells in the presence of Cd2+ in vitro.

The epidemiological studies and recent data have provided convinced evidence that green tea and its major constituent epigallocatechin gallate (EGCG) might have the potential to lower the risk of cancers in humans. Metal ions, such as zinc and cadmium, which are necessary to our health, are important factors inducing many diseases including prostate cancer in the condition of absence or excess. EGCG can satisfactorily exhibit complex chemistry with metal ions because of multiple hydroxyl states, which in turn changes their bioactivities and metabolism pathways. This paper presents the results of an investigation of the cytotoxicity of EGCG against PC-3 prostate cancer cells in the presence and absence of Cd2+ in vitro. The results showed that both EGCG and Cd2+ suppressed viability and clonegenecity of PC-3 cells, and the suppression effect was enhanced when EGCG added with Cd2+. Although Cd2+ up-regulated the 67 kDa laminin receptor (67LR), which is a migration-associated protein, the cell migration ability was not significantly increased after each treatment. We also found that EGCG and Cd2+ directly interacted with mitochondrial, and the mixture of EGCG and Cd2+ (EGCG+Cd2+) significantly caused loss of the mitochondrial membrane potential, decrease of the ATP content and activation of caspase-9 compared with EGCG treated alone. Taken together, these findings suggest that Cd2+ enhanced the cytotoxicity of EGCG to PC-3 cells by up-regulating the 67LR and the mitochondria-mediated apoptosis pathway.

Stabilization of mitochondrial membrane potential and improvement of neuronal energy metabolism by Ginkgo biloba extract EGb 761.

Ginkgo biloba extract EGb 761 has been used for many years to treat age-related cognitive disorders including Alzheimer's disease. EGb 761 given shortly after initiating mitochondrial damage by sodium nitroprusside (nitric oxide donor) improved the mitochondrial membrane potential of PC12 cells significantly and dose dependently. Under these conditions, EGb 761 also reversed the decrease in ATP production. In addition, similar protection against oxidative damage was found in dissociated brain cells and isolated brain mitochondria after in vitro or in vivo treatment with EGb 761. Moreover, PC12 cells bearing an Alzheimer's disease-related mutation in the amyloid precursor protein, which leads to enhanced beta amyloid production, showed greater benefit from treatment with EGb 761 than did control cells. Taken together, our findings clearly show stabilization and protection of mitochondrial function as a specific and very sensitive property of EGb 761 at therapeutically relevant doses.