s-trans-trans-farnesylthiosalicylic-acid and Disease-Models--Animal

Farnesylthiosalisylic acid (FTS) is a potent non-toxic anticancer drug that targets oncogenic and pathologically activated Ras. The mechanism of action of FTS is well understood. It interferes with the binding of activated Ras proteins to their escort chaperons and with Ras tethering to the plasma membrane. This agent has been evaluated successfully in phase II clinical trials of pancreatic and lung cancer patients. It is generally agreed that Ras proteins play an important role in cancer, but they also drive activation of the immune system. Therefore we hypothesized that inhibiting Ras might be beneficial in autoimmune and inflammatory conditions. Over the past decade we have extensively studied the effects of FTS in multiple animal models of such diseases. We were able to show potent anti-inflammatory properties of FTS in autoimmune disease models such as systemic lupus erythematous, antiphospholipd syndrome, Guillain-Barré syndrome, multiple sclerosis, and inflammatory bowel diseases. Its potential was also shown in type I and type II diabetes. Animal models of contact dermatitis, allergic inflammation, and proliferative nephritis were studied as well. We have also investigated the molecular mechanisms, signaling pathways, and inflammatory mediators underlying these conditions. In this review we summarize our (and others) published data, and conclude that FTS has great potential as a safe anti-inflammatory drug.

Topics: Animals; Anti-Inflammatory Agents; Autoimmune Diseases; Diabetes Mellitus, Type 2; Disease Models, Animal; Farnesol; Humans; Protein Binding; ras Proteins; Salicylates

Ras activation is a frequent event in hepatocellular carcinoma (HCC). Combining a RAS inhibitor with traditional clinical therapeutics might be hampered by a variety of side effects, thus hindering further clinical translation. Herein, we report on integrating an IR820 nanocapsule-augmented sonodynamic therapy (SDT) with the RAS inhibitor farnesyl-thiosalicylic acid (FTS). Using cellular and tumor models, we demonstrate that combined nanocapsule-augmented SDT with FTS induces an anti-tumor effect, which not only inhibits tumor progression, and enables fluorescence imaging. To dissect the mechanism of a combined tumoricidal therapeutic strategy, we investigated the scRNA-seq transcriptional profiles of an HCC xenograft following treatment.. Integrative single-cell analysis identified several clusters that defined many corresponding differentially expressed genes, which provided a global view of cellular heterogeneity in HCC after combined SDT/FTS treatment. We conclude that the combination treatment suppressed HCC, and did so by inhibiting endothelial cells and a modulated immunity. Moreover, hepatic stellate secretes hepatocyte growth factor, which plays a key role in treating SDT combined FTS. By contrast, enrichment analysis estimated the functional roles of differentially expressed genes. The Gene Ontology terms "cadherin binding" and "cell adhesion molecule binding" and KEGG pathway "pathway in cancer" were significantly enriched by differentially expressed genes after combined SDT/FTS therapy.. Thus, some undefined mechanisms were revealed by scRNA-seq analysis. This report provides a novel proof-of-concept for combinatorial HCC-targeted therapeutics that is based on a non-invasive anti-tumor therapeutic strategy and a RAS inhibitor.

Topics: Animals; Antineoplastic Agents; Carcinoma, Hepatocellular; Cell Line, Tumor; Combined Modality Therapy; Diathermy; Disease Models, Animal; Endothelial Cells; Farnesol; Female; Gene Expression Regulation, Neoplastic; Hep G2 Cells; Humans; Liver Neoplasms; Mice, Inbred BALB C; Mice, Nude; ras Proteins; Salicylates; Sequence Analysis, RNA

Alzheimer's disease (AD), a leading cause of dementia, becomes a serious health issue for individuals and society around the world. AD is a neurodegenerative disease characterized by the deposition of amyloid-β (Aβ) peptides and neurofibrillary tangles (NFT) and the loss of large numbers of neurons. To date, there is no effective treatment for AD, and thus, to enhance neurogenesis in the AD brain may be a therapeutic strategy. RAS signaling pathway involves in synaptic plasticity and memory formation, which is overexpressed in brains with AD. This study used Aβ. The results demonstrated that FTS could prevent Aβ. In conclusion, these findings suggest that FTS as a RAS inhibitor could be a potential therapeutic agent for the treatment of AD.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Animals; Disease Models, Animal; Doublecortin Protein; Extracellular Signal-Regulated MAP Kinases; Farnesol; Injections, Intraperitoneal; Male; MAP Kinase Signaling System; Maze Learning; Mice; Mice, Inbred ICR; Molecular Structure; Neuroprotective Agents; ras Proteins; Salicylates; Stereoisomerism

Rheumatoid arthritis (RA) is an autoimmune disease characterized by pronounced inflammation and leucocyte infiltration in affected joints. Despite significant therapeutic advances, a new targeted approach is needed. Our objective in this work was to investigate the anti-inflammatory effects of the Ras inhibitor farnesylthiosalicylic acid (FTS) on adjuvant-induced arthritis (AIA) in rats, an experimental model for RA. Following AIA induction in Lewis rats by intradermal injection of heat-killed Mycobacterium tuberculosis, rats were treated with either FTS or dexamethasone and assessed daily for paw swelling. Joints were imaged by magnetic resonance imaging and computerized tomography and analysed histologically. The anti-inflammatory effect of FTS was assessed by serum assay of multiple cytokines. After adjuvant injection rats demonstrated paw swelling, leucocyte infiltration, cytokine secretion and activation of Ras-effector pathways. Upon FTS treatment these changes reverted almost to normal. Histopathological analysis revealed that the synovial hyperplasia and leucocyte infiltration observed in the arthritic rats were alleviated by FTS. Periarticular bony erosions were averted. Efficacy of FTS treatment was also demonstrated by inhibition of CD4(+) and CD8(+) T cell proliferation and of interferon (IFN)-γ, tumour necrosis factor (TNF)-α, interleukin (IL)-6 and IL-17 release. The Ras effectors PI3K, protein kinase B (AKT), p38, and extracellular-regulated kinase (ERK) were significantly attenuated and forkhead box protein 3 (FoxP3) transcription factor, a marker of regulatory T cells, was significantly increased. Thus, FTS possesses significant anti-inflammatory and anti-arthritic properties and accordingly shows promise as a potential therapeutic agent for RA. Its effects are apparently mediated, at least in part, by a decrease in proinflammatory cytokines.

Topics: Animals; Anti-Inflammatory Agents; Arthritis, Experimental; Arthritis, Rheumatoid; Cytokines; Disease Models, Animal; Farnesol; Inflammation Mediators; Joints; Male; ras GTPase-Activating Proteins; Rats; Salicylates; Signal Transduction; T-Lymphocyte Subsets

We have recently designed and developed a dual-functional drug carrier that is based on poly(ethylene glycol) (PEG)-derivatized farnesylthiosalicylate (FTS, a nontoxic Ras antagonist). PEG5K-FTS2 readily form micelles (20-30 nm) and hydrophobic drugs such as paclitaxel (PTX) could be effectively loaded into these micelles. PTX formulated in PEG5K-FTS2 micelles showed an antitumor activity that was more efficacious than Taxol in a syngeneic mouse model of breast cancer (4T1.2). In order to further improve our PEG-FTS micellar system, four PEG-FTS conjugates were developed that vary in the molecular weight of PEG (PEG2K vs PEG5K) and the molar ratio of PEG/FTS (1/2 vs 1/4) in the conjugates. These conjugates were characterized including CMC, drug loading capacity, stability, and their efficacy in delivery of anticancer drug PTX to tumor cells in vitro and in vivo. Our data showed that the conjugates with four FTS molecules were more effective than the conjugates with two molecules of FTS and that FTS conjugates with PEG5K were more effective than the counterparts with PEG2K in forming stable mixed micelles. PTX formulated in PEG5K-FTS4 micelles was the most effective formulation in inhibiting the tumor growth in vivo.

Topics: Animals; Breast Neoplasms; Disease Models, Animal; Drug Carriers; Farnesol; Female; HCT116 Cells; Hemolysis; Humans; Inhibitory Concentration 50; Magnetic Resonance Spectroscopy; Mammary Neoplasms, Experimental; MCF-7 Cells; Mice; Mice, Inbred BALB C; Micelles; Paclitaxel; Polyethylene Glycols; Salicylates

Activation of Ras and its downstream signaling pathways, likely contribute to the development of hepatocarcinoma. We have previously shown that intraperitoneal injections of the Ras inhibitor S-trans, trans-farnesylthiosalicyclic acid (FTS) blocks Ras activation and prevents heptocarcinoma development in rats receiving weekly injections of the carcinogene diethylnitrosamine (DEN) for 16 wk. Using this in vivo model, we evaluated the relationship between the tumor preventive effect of Ras inhibition and activation of downstream signaling pathways, cell proliferation, cell cycle events, and angiogenesis. Western blotting, quantitative PCR, immunohistochemistry, and transcription factor activity assays were used. DEN-induced activation of NFkB and Stat3 was abrogated by FTS treatment. FTS treatment showed no effect on DEN-induced elevation of TNFα, interleukin 6 and TLR4, known activators of these transcription factors. FTS significantly reduced phosphorylation of the MAPkinase p38 and of the p70S6 kinase, a surrogate marker for mTor activation, without affecting ERK and AKT phosphorylation. These events were associated with reduced c-myc and cyclin D expression as well as reduced cell proliferation in transformed, GSTp-positive hepatocytes. Moreover, FTS treatment shifted cell proliferation from transformed hepatocytes to apparently normal, GSTp negative hepatocytes. FTS treatment did not down-regulate expression of angiogenesis markers HIFα, VEGF, VEGF receptor1, and placenta growth factor. FTS treatment inhibits important signaling pathways involved in cellular proliferation leading to strongly reduced proliferation of transformed hepatocytes without affecting normal hepatocytes. This re-adjustment of the proliferation balance likely contributes to the tumor preventive of FTS in the context of Ras inhibition in hepatocarcinogenesis.

Topics: Animals; Anticarcinogenic Agents; Carcinogens; Cell Cycle; Cell Proliferation; Cyclin D; Diethylnitrosamine; Disease Models, Animal; Down-Regulation; Farnesol; Inflammation; Liver Neoplasms, Experimental; Male; Neovascularization, Pathologic; NF-kappa B; p38 Mitogen-Activated Protein Kinases; Phosphorylation; Proto-Oncogene Proteins c-myc; ras Proteins; Rats; Rats, Wistar; Salicylates; STAT3 Transcription Factor

The Ras superfamily of guanosine-triphosphate (GTP)-binding proteins regulates a diverse spectrum of intracellular processes involved in inflammation and fibrosis. Farnesythiosalicylic acid (FTS) is a unique and potent Ras inhibitor which decreased inflammation and fibrosis in experimentally induced liver cirrhosis and ameliorated inflammatory processes in systemic lupus erythematosus, neuritis and nephritis animal models. FTS effect on Ras expression and activity, muscle strength and fibrosis was evaluated in the dy(2J)/dy(2J) mouse model of merosin deficient congenital muscular dystrophy. The dy(2J)/dy(2J) mice had significantly increased RAS expression and activity compared with the wild type mice. FTS treatment significantly decreased RAS expression and activity. In addition, phosphorylation of ERK, a Ras downstream protein, was significantly decreased following FTS treatment in the dy(2J)/dy(2J) mice. Clinically, FTS treated mice showed significant improvement in hind limb muscle strength measured by electronic grip strength meter. Significant reduction of fibrosis was demonstrated in the treated group by quantitative Sirius Red staining and lower muscle collagen content. FTS effect was associated with significantly inhibition of both MMP-2 and MMP-9 activities. We conclude that active RAS inhibition by FTS was associated with attenuated fibrosis and improved muscle strength in the dy(2J)/dy(2J) mouse model of congenital muscular dystrophy.

Topics: Animals; Base Sequence; Blotting, Western; Disease Models, Animal; DNA Primers; Farnesol; Fibrosis; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Mice; Mice, Inbred C57BL; Muscle Strength; Muscular Dystrophies; ras Proteins; Salicylates

In the present work, we have evaluated the possibility of preventing liver carcinogenesis in rats at two stages of development. In the first series of experiments, we induced foci of altered hepatocytes, (FAH) which represent the first events in rodent liver carcinogenesis, using the chemical mutagens diethylnitrosamine (DEN) and acetylaminofluorene (AAF). In the second part of the work, we used repeated weekly injections of DEN only that gave rise to significant fibrosis at 11 weeks and the development of malignant tumours at 16 weeks. We chose to assess the chemopreventive effect of three different drugs: pioglitazone, lanreotide and S-trans-trans-farnesylthiosalicylic acid (FTS). Pioglitazone (PGZ) is an agonist of peroxisome proliferator-activated receptor gamma (PPARg), itself a member of the nuclear receptor superfamily, responsible for the modulation of a number of metabolic pathways, including cell differentiation, metabolism of lipids and inflammation. Lanreotide (LAN) is a somatostatin analogue that has an inhibitory effect on the release of several hormones, such as growth hormone and serotonine. FTS is a specific antagonist of the protoocogene Ras, tested here based on the rationale that Ras is activated in many hepatocellular carcinomas (HCC). We showed that both PGZ and LAN were efficient in the first, pre-neoplastic model, by reducing the size of FAH, decreasing proliferation specifically in FAH by interacting with proteins of the cell cycle. We could also demonstrate that LAN increased apoptosis. In the second model, LAN was able to diminish the number of established HCC by decreasing proliferation, in parallel with an anti-fibrotic action. Furthermore, enhanced apoptosis and antiangiogenic effects were observed when LAN was given from the start of the carcinogenic induction by DEN. The cellular mechanisms leading to its effects warrant further investigations. FTS also strongly inhibited the appearance of FAH and HCC in the second model, through a complete inhibition of Ras activation and the induction of pro-apoptotic pathways. On the contrary, PGZ did not prevent the appearance of neoplastic lesions. For these reasons, we did not analyse further its mechanism of action in the second model. Altogether, the results we obtained demonstrate an activity of both LAN and FTS, at the early onset of liver carcinogenesis, and later on when advanced fibrosis, cirrhosis and HCC are induced. These anti-tumoural effects could be complementary and will

Topics: Animals; Antineoplastic Agents; Carcinoma, Hepatocellular; Disease Models, Animal; Farnesol; Humans; Hypoglycemic Agents; Liver Neoplasms; Peptides, Cyclic; Pioglitazone; Salicylates; Somatostatin; Thiazolidinediones

We hypothesized that Ras proximate 1 (Rap1) functions as an additional target for farnesylthiosalicylic acid (FTS) or its derivatives, and that the inhibition of Rap1 in lymphocytes by these agents may represent a method for treating inflammatory disorders. Indeed, we found that FTS-amide (FTS-A) was able to inhibit the elicitation phase of delayed cutaneous hypersensitivity in vivo. This effect was associated with the inhibition of Rap1 more than with the inhibition of Harvey rat sarcoma viral oncogene (Ras). Moreover, FTS-A inhibited Rap1 and contact sensitivity far better than FTS. We suggest that FTS-A may serve as a possible therapeutic tool in contact sensitivity in particular and T-cell-mediated inflammation in general.

Topics: Amides; Animals; Cell Membrane; Disease Models, Animal; Farnesol; Female; Green Fluorescent Proteins; Guanosine Triphosphate; Humans; Immunohistochemistry; Jurkat Cells; Lymphocytes; Mice; Mice, Inbred BALB C; Phospholipase D; rap1 GTP-Binding Proteins; ras Proteins; Salicylates; Shelterin Complex; Skin; T-Lymphocytes; Telomere-Binding Proteins; Tumor Necrosis Factor-alpha

Anaplastic thyroid carcinomas are deadly tumors that are highly invasive, particularly into the bones. Although oncogenic Ras can transform thyroid cells into a severely malignant phenotype, thyroid carcinomas do not usually harbor ras gene mutations. Therefore, it is not known whether chronically active Ras contributes to thyroid carcinoma cell proliferation, although galectin-3 (Gal-3), which is strongly expressed in thyroid carcinomas but not in benign tumors or normal glands, is known to act as a K-Ras chaperone that stabilizes and drives K-Ras.GTP nanoclustering and signal robustness. Here, we examined the possibility that thyroid carcinomas expressing high levels of Gal-3 exhibit chronically active K-Ras. Using cell lines representing three types of malignant thyroid tumors--papillary, follicular, and anaplastic--we investigated the possible correlation between Gal-3 expression and active Ras content, and then examined the therapeutic potential of the Ras inhibitor S-trans, trans-farnesylthiosalicylic acid (FTS; Salirasib) for thyroid carcinoma. Thyroid carcinoma cells strongly expressing Gal-3 showed high levels of K-Ras.GTP expression, and K-Ras.GTP transmitted strong signals to extracellular signal-regulated kinase. FTS disrupted interactions between Gal-3 and K.Ras, strongly reduced K-Ras.GTP and phospho-extracellular signal-regulated kinase expression, and enhanced the expression of the cell cycle inhibitor p21 as well as of the thyroid transcription factor 1, which is involved in thyroid cell differentiation. FTS also inhibited anaplastic thyroid carcinoma cell proliferation in vitro and tumor growth in nude mice. We conclude that wild-type K-Ras.GTP in association with Gal-3 contributes to thyroid carcinoma malignancy and that Ras inhibition might be a useful treatment strategy against these deadly tumors.

Topics: Animals; Cell Differentiation; Cell Line, Tumor; Cell Membrane; Cell Proliferation; Cyclin-Dependent Kinase Inhibitor p21; Disease Models, Animal; Down-Regulation; Enzyme Activation; Extracellular Signal-Regulated MAP Kinases; Farnesol; Galectin 3; Gene Expression Regulation, Neoplastic; Guanosine Triphosphate; Humans; Mice; Nuclear Proteins; Protein Transport; Proto-Oncogene Proteins; Proto-Oncogene Proteins p21(ras); ras Proteins; Salicylates; Signal Transduction; Thyroid Neoplasms; Thyroid Nuclear Factor 1; Transcription Factors; Xenograft Model Antitumor Assays

EAE is a common animal model for multiple sclerosis (MS). Immunomodulatory treatments such as glatiramer acetate (GA, Copaxone) are beneficial in EAE but are not universally effective in the clinic. The Ras inhibitor farnesylthiosalycylic acid (FTS, Salirasib), efficiently ameliorate EAE as well. Here we demonstrate a synergistic beneficial effect of the combined GA and FTS treatment on EAE; 22.5% of the combined-treatment mice developed disease compared to 87.5%, 77.5% and 82.5% of mice treated with vehicle, GA and FTS, respectively, results supported by MRI, histological, immunological and biochemical data. Such a combined treatment may improve clinical outcome in MS patients.

Topics: Animals; Carrier Proteins; CD3 Complex; Cell Proliferation; Cytokines; Demyelinating Diseases; Disease Models, Animal; DNA Helicases; Drug Synergism; Drug Therapy, Combination; Encephalomyelitis, Autoimmune, Experimental; Enzyme Inhibitors; Enzyme-Linked Immunosorbent Assay; Extracellular Signal-Regulated MAP Kinases; Farnesol; Female; Forkhead Transcription Factors; Glatiramer Acetate; Immunosuppressive Agents; Leukemic Infiltration; Magnetic Resonance Imaging; Mice; Mice, Inbred C57BL; Peptides; Poly-ADP-Ribose Binding Proteins; RNA Helicases; RNA Recognition Motif Proteins; Salicylates; Spinal Cord; Spleen; Statistics, Nonparametric; Time Factors

The Ras inhibitor S-trans,trans-farnesylthiosalicylic acid (FTS, Salirasib) interferes with Ras membrane interactions that are crucial for Ras-dependent transformation. It remains unknown whether modifications of the carboxyl group of FTS can affect its activity. Here we show that specific modifications of the FTS carboxyl group by esterification or amidation yield compounds with improved growth inhibitory activity, compared to FTS, as shown in Panc-1 and U87 cells. The most potent compounds were FTS-methoxymethyl ester and FTS-amide. However, selectivity toward active Ras-GTP, as known for FTS, was apparent with the amide derivatives of FTS. FTS-amide exhibited the overall highest efficacy in inhibition of Ras-GTP and cell growth. This new compound significantly inhibited growth of both Panc-1 tumors and U87 brain tumors. Thus amide derivatives of the FTS carboxyl group provide potent cell-growth inhibitors without loss of selectivity toward the active Ras protein and may serve as new candidates in cancer therapy.

Topics: Amides; Animals; Antineoplastic Agents; Cell Line, Tumor; Cyclic AMP-Dependent Protein Kinases; Disease Models, Animal; Disease Progression; Enzyme Inhibitors; Extracellular Signal-Regulated MAP Kinases; Farnesol; Humans; MAP Kinase Signaling System; Mice; Mice, Nude; Molecular Structure; Neoplasms; Oncogene Protein p21(ras); Salicylates; Xenograft Model Antitumor Assays

Myocardial injury, developed after a period of ischemia/reperfusion (I/R) results in the destruction of functional heart tissue, this being replaced by scar tissue. Intracellular signaling pathways mediating cardiomyocyte death are partially understood and involve the activation of Ras. p38-MAPK, JNK and Mst-1 are downstream effectors of Ras protein. We hypothesized that S-farnesylthiosalicylic acid (FTS), a synthetic small molecule that detaches Ras from the inner cell membrane, consequently inhibiting Ras activity, reduces I/R myocardial injury in vitro and in vivo. Wistar rat hearts were isolated, mounted on the Langendorff apparatus and subjected to ischemia (30 min, 37 degrees C) and reperfusion. During the reperfusion period, the hearts were perfused with FTS (1 microM) solution or control buffer. Left anterior descending (LAD) ligation and subsequent reperfusion was performed in two groups of Wistar rats. Rats received 5mg/kg FTS or PBS according to two protocols: (A) FTS or PBS were administered daily 7 days prior, immediately before and 14 days (every other day) after LAD occlusion or (B) every other day for 14 days post-I/R. Hearts from FTS-treated rats (Langendorff) and FTS-treated rats (protocol A) showed a significant improvement in myocardial performance and smaller scar tissue compared with the PBS group. Infarct size in the FTS-treated group was 12.7+/-2% vs. 23.7+/-4% in the PBS-treated (in vitro) group and 17.3+/-2.5% vs. 36+/-7% compared with control I/R rats (in vivo) p<0.05. These effects may be associated with the down regulation of JNK as a short-term effector and with Mst-1 in the long-term remodeling process.

Topics: Animals; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Administration Schedule; Farnesol; Heart Function Tests; In Vitro Techniques; Male; Myocardial Reperfusion Injury; Myocardium; ras Proteins; Rats; Rats, Inbred Lew; Rats, Wistar; Salicylates

Ras proteins play a role in receptor-mediated signaling pathways and are activated after traumatic brain injury. S-trans-trans-farnesylthiosalicylic acid (FTS), a synthetic Ras inhibitor, acts primarily on the active, GTP-bound form of Ras and was shown to improve neurobehavioral outcome after closed head injury (CHI) in mice. To gain a better understanding of the neuroprotective mechanism of FTS, we used diffusion-weighted imaging (DWI) in a rat model of CHI. Apparent diffusion coefficients (ADC) and transverse relaxation times (T2) were measured in injured rat brains after treatment with vehicle or FTS (5 mg/kg). Neuroprotection by FTS was also assessed in terms of the neurological severity score. One week after injury, significantly better recovery was observed in the FTS-treated rats than in the controls (p = 0.0191). T2 analysis of the magnetic resonance images revealed no differences between the two groups. In contrast, they differed significantly in ADC, particularly at 24 h post-CHI (p < 0.05): in the vehicle-treated rats ADC had decreased to approximately 26% below baseline, whereas it had increased to about 10% above baseline in the FTS-treated rats. As the magnitude of ADC reduction is strongly linked to blood perfusion deficit, these results suggest that the neuroprotective mechanism of FTS might be related to an improvement in cerebral perfusion. We propose that FTS, which is currently being tested in humans for anti-cancer indications, should also be considered as a new strategy for the management of head injury.

Topics: Animals; Brain Injuries; Diffusion Magnetic Resonance Imaging; Disease Models, Animal; Farnesol; Male; Motor Activity; ras Proteins; Rats; Recovery of Function; Salicylates; Time Factors

EAN induced in Lewis rats by immunization with peripheral bovine myelin was treated by the Ras inhibitor farnesylthiosalicylate (FTS). Treatment from day 0 with FTS (5 mg/kg intraperitoneally twice daily) attenuated peak clinical scores (mean+/-S.E., 2.5+/-0.5 compared to 4.1+/-0.5 in saline treated controls, p=0.018, t-test) but not recovery. Treatment from day 10 with FTS attenuated peak disability (2.5+/-0.6, p=0.032 compared to saline treated controls) and improved recovery (0.84+/-0.42, untreated controls 2.4+/-0.6, p=0.028 by repeated measures ANOVA). Effects were confirmed by rotarod and nerve conduction studies. An inactive analogue, geranylthiosalicylate, had no clinical effect. Inhibition of Ras is of potential use in the treatment of inflammatory neuropathies.

Topics: Analysis of Variance; Animals; Behavior, Animal; Body Weight; Cell Proliferation; Cells, Cultured; Concanavalin A; Disease Models, Animal; Dose-Response Relationship, Immunologic; Drug Interactions; Electromyography; Enzyme Inhibitors; Farnesol; Female; Lymphocytes; Motor Activity; Mycobacterium tuberculosis; Myelin Proteins; Neural Conduction; Neuritis, Autoimmune, Experimental; ras Proteins; Rats; Rats, Inbred Lew; Rotarod Performance Test; Salicylates; Severity of Illness Index

Neointimal formation with and without previous vascular injury is common after balloon dilation and in transplant arteriosclerosis. It involves proliferation and migration of medial smooth muscle cells and inflammation, processes that are regulated by Ras proteins and their down-stream effectors. Farnesylthiosalicylate (FTS) is a Ras inhibitor that interferes with Ras membrane anchorage and affects Ras proteins in their active state. In the present study, we tested the hypothesis that systemic administration of FTS will suppress intimal thickening in the rat carotid injury model.. The effects of FTS on rat vascular smooth muscle cells (VSMC) and splenocytes proliferation were evaluated in vitro. The in vivo effects of FTS on the neointima of balloon-injured male Wistar rats, treated daily for 2 weeks with FTS (5 mg/kg weight, intraperitoneally) were evaluated by determination of Ras, Ras-GTP, and active ERK levels (3 days after injury), and by quantitative determination of the extent of intimal thickening and immunohistochemistry for Ras, iNOS, NFkB, and Ki-67 (2 weeks after injury). FTS inhibited VSMC and splenocyte proliferation as well as interferon-gamma secretion by splenocytes in a dose-dependent manner. Compared with controls, FTS treatment resulted in a strong decrease in Ras-GTP and active ERK, and it significantly reduced intimal thickening after the injury. Ras expression appeared predominantly at areas of neointima regardless of the treatment group. NFkB and iNOS-positive cell numbers were reduced in sections of FTS treated rats.. FTS appears to act as a potent inhibitor of intimal thickening in a model of experimental arterial injury.

Topics: Animals; Carotid Artery Injuries; Carotid Artery, Common; Cell Division; Cells, Cultured; Disease Models, Animal; Endothelium, Vascular; Enzyme Activation; Farnesol; GTP-Binding Proteins; Immunohistochemistry; Interferon-gamma; Male; Mitogen-Activated Protein Kinases; Muscle, Smooth, Vascular; ras Proteins; Rats; Rats, Wistar; Salicylates; Spleen; Tunica Intima

Cerebellar granule neurons undergo apoptosis when switched from a medium containing high potassium (HK) to one that has low potassium (LK). LK-induced cell death is blocked by GW5074 [5-Iodo-3-[(3,5-dibromo-4-hydroxyphenyl) methylene]-2-indolinone], a synthetic drug that inhibits c-Raf activity in vitro. GW5074 has no direct effect on the activities of several apoptosis-associated kinases when assayed in vitro. In contrast to its effect in vitro, treatment of neurons with GW5074 causes c-Raf activation (when measured in vitro in the absence of the drug) and stimulates the Raf-MEK-ERK pathway. Treatment of neurons with GW5074 also leads to an increase in the activity of B-Raf, which is not inhibited by GW5074 in vitro at concentrations at which the drug exerts its neuroprotective effect. PD98059 and U0126, two distinct inhibitors of MEK, block the activation of ERK by GW5074 but have no effect on its ability to prevent cell death. Overexpression of a dominant-negative form of Akt does not reduce the efficacy of GW5074, demonstrating an Akt-independent mechanism of action. Neuroprotection is inhibited by SN-50, a specific inhibitor of nuclear factor-kappa B (NF-kappaB) and by the Ras inhibitor S-trans, trans-farnesylthiosalicylic acid (FTS) implicating NF-kappaB and Ras in the neuroprotective signaling pathway activated by GW5074. In addition to preventing LK-induced apoptosis, treatment with GW5074 protects against the neurotoxic effects of MPP+ and methylmercury in cerebellar granule neurons, and glutathione depletion-induced oxidative stress in cortical neurons. Furthermore, GW5074 prevents neurodegeneration and improves behavioral outcome in an animal model of Huntington's disease. Given its neuroprotective effect on distinct types of cultured neurons, in response to different neurotoxic stimuli, and in an animal model of neurodegeneration, GW5074 could have therapeutic value against neurodegenerative pathologies in humans.

Topics: Animals; Cell Death; Cells, Cultured; Disease Models, Animal; Enzyme Inhibitors; Farnesol; Huntington Disease; Indoles; Mitogen-Activated Protein Kinase Kinases; Mitogen-Activated Protein Kinases; Neurodegenerative Diseases; Neurons; Neuroprotective Agents; Neurotoxins; Nitro Compounds; Phenols; Propionates; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins c-raf; Rats; Rats, Sprague-Dawley; Salicylates; Signal Transduction

Stimulation and proliferation of lymphocytes require activation of Ras. S-farnesylthiosalicylic acid (FTS) is a synthetic substance that detaches Ras from the inner cell membrane and induces its rapid degradation. Antiphospholipid antibodies (aPL) are a heterogeneous group of antibodies detected in patients with antiphospholipid syndrome (APS), which is associated with thrombosis, pregnancy losses, and thrombocytopenia.. To examine the effect of FTS treatment on aPL levels in a genetic autoimmune model (the MRL/lpr mice) and in an induced model of APS.. Female Balb/C mice immunized once with beta2-glycoprotein I (beta2-GPI) in complete Freund's adjuvant (CFA) and female MRL/lpr mice were treated intraperitoneally with either FTS (5 mg/Kg/day) or saline 3-5 times a week. aPL and anti-beta2-GPI antibodies were measured by ELISA.. FTS treatment 3 times a week resulted in significant decreases of aPL and anti-beta2-GPI antibodies in both animal models. In contrast, more frequent treatment (5 times a week) had no significant effect on autantibody levels in both animal models. We further compared 2 protocols in the induced APS model, one for alternate day treatment and the other for daily treatment on the first 3 days each week, and found a decrease in autoantibody levels only in the alternate day protocol.. Inhibition of Ras activation by FTS is effective in decreasing autoantibody levels in models of APS. The differential modulation of immune function by alternate day compared to daily treatment may provide better understanding of the role of Ras activation in this system.

Topics: Animals; Antibodies, Antiphospholipid; Antiphospholipid Syndrome; Autoantibodies; beta 2-Glycoprotein I; Disease Models, Animal; Enzyme Inhibitors; Enzyme-Linked Immunosorbent Assay; Farnesol; Female; Freund's Adjuvant; Glycoproteins; Mice; Mice, Inbred BALB C; Mice, Inbred MRL lpr; ras Proteins; Salicylates; Time Factors

Traumatic brain injury activates N-methyl-d-aspartate receptors (NMDAR) inducing activation of the Ras protein (a key regulator of cell growth, survival, and death) and its effectors. Thus, trauma-induced increase in active Ras-GTP might contribute to traumatic brain injury pathology. Based on this hypothesis, a new concept of neuroprotection is proposed, examined here by investigating the effect of the Ras inhibitor S-trans, trans-farnesylthiosalicylic acid (FTS) in a mouse model of closed head injury (CHI). Mice subjected to CHI were treated systemically 1 h later with FTS (5 mg/kg) or vehicle. After 1 h, Ras-GTP in the contused hemisphere showed a significant (3.8-fold) increase, which was strongly inhibited by FTS (82% inhibition) or by the NMDA-receptor antagonist MK-801 (53%). Both drugs also decreased active (phosphorylated) extracellular signal-regulated kinase. FTS prevented the CHI-induced reduction in NMDAR binding in cortical, striatal, and hippocampal regions, measured by [3H]-MK-801 autoradiography, and decreased lesion size by 50%. It also reduced CHI-induced neurologic deficits, indicated by the highly significant (P < 0.0001) 60% increase in extent of recovery. Thus, FTS provided long-term neuroprotection after CHI, rescuing NMDAR binding in the contused hemisphere and profoundly reducing neurologic deficits. These findings suggest that nontoxic Ras inhibitors such as FTS may qualify as neuroprotective drugs.

Topics: Animals; Brain Injuries; Disease Models, Animal; Enzyme Inhibitors; Farnesol; Guanosine Triphosphate; Head Injuries, Closed; Male; Mice; Mice, Inbred C57BL; Mitogen-Activated Protein Kinases; Neuroprotective Agents; ras Proteins; Receptors, N-Methyl-D-Aspartate; Recovery of Function; Salicylates

Atherosclerosis is a multifactorial disorder involving inflammatory processes. These responses are associated with robust activation of signaling cascades by diverse cell surface receptors in a variety of cell types. The processes that are involved in atherosclerosis would likely require intact Ras pathways, which play a key role in the control of cell growth, differentiation, and apoptosis.. We examined whether the Ras inhibitor farnesyl thiosalicylic acid (FTS) can suppress atherogenesis in the apolipoprotein E-deficient mouse model. Mice were treated with FTS or a control regimen 3 times weekly for 6 weeks and fed a normal chow diet. Two additional groups included FTS-treated and control-treated mice that were fed a high-fat diet for 10 weeks. FTS reduced both fatty streaks and advanced lesions compared with the control treatment. Ras inhibition in vivo was evidenced by the reduced content of the active form of Ras (Ras-GTP) in aortas of FTS-treated mice. Splenocytes from the FTS-treated versus control mice exhibited reduced proliferation to oxidized LDL (OxLDL) but not to concanavalin A. IgG anti-OxLDL antibody levels were reduced in FTS-treated mice compared with controls. Whereas no effect of FTS was evident on plaque T lymphocyte and macrophage content, lesional vascular cell adhesion molecule-1 and nuclear factor-kappaB expression were considerably reduced compared with controls.. FTS suppressed atherosclerotic plaques in apolipoprotein E-deficient mice, providing a useful tool for research in atherosclerosis.

Topics: Animals; Aorta; Apolipoproteins E; Arteriosclerosis; Autoantibodies; Cell Division; Cells, Cultured; Cholesterol; Dietary Fats; Disease Models, Animal; Enzyme Inhibitors; Farnesol; Injections, Intraperitoneal; Lipoproteins, LDL; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; NF-kappa B; ras Proteins; Salicylates; Spleen; Treatment Outcome; Triglycerides; Vascular Cell Adhesion Molecule-1