A data-guided approach for the evaluation of zeolites for hydrogen storage with the aid of molecular simulations

CONTEXT

This study employs a data-guided approach to evaluate zeolites for hydrogen storage, utilizing molecular simulations. The development of efficient and practical hydrogen storage materials is crucial for advancing clean energy technologies. Zeolites have shown promise as potential candidates due to their unique porous structure and tunable properties. However, the selection and design of suitable zeolites for hydrogen storage remain challenging. Therefore, this work aims to address this materials science question by utilizing molecular simulations and data-guided approaches to evaluate zeolites' performance for hydrogen storage. The results obtained from this study provide valuable insights into the evaluation of zeolites for hydrogen storage. Through molecular simulations, we analyze the adsorption behavior of hydrogen molecules in various zeolite structures. The performance of different zeolite frameworks in terms of hydrogen storage capacity, adsorption energy, and diffusion properties is assessed. Linde type A zeolite (LTA) had the highest capacity with a hydrogen capacity of 4.8wt% out of the 233 investigated zeolites. Furthermore, we investigate the influence of different factors such as mass (M), density (D), helium void fraction (HVF), accessible pore volume (APV), gravimetric surface area (GSA), and largest overall cavity diameter (Di) on the hydrogen storage performance of zeolites. The results show that Di, D, and M have a negative effect on the percentage weight capacity, while GSA and VSA have the highest positive contribution to the percentage weight. This study, therefore, provides new insights into the factors that affect their hydrogen storage capacity by exhibiting the importance of considering multiple factors when evaluating the performance of zeolites and demonstrates the potential of combining different computational methods to provide a more comprehensive understanding of materials. The current study contributes to the understanding of zeolite-based materials for hydrogen storage applications, aiding in the development of more efficient and practical hydrogen storage systems.

METHODS

Computational techniques were employed to investigate the hydrogen storage properties of zeolites. Molecular simulations were performed using classical force fields and molecular dynamics methods. The calculations were carried out at a force field level of theory with the GGA functional. To accurately capture the thermodynamics and kinetics of hydrogen adsorption, enhanced sampling techniques such as Monte Carlo simulations and molecular dynamics with metadynamics were utilized. We employed Grand Canonical Monte Carlo (GCMC) simulations to model hydrogen adsorption in zeolite structures for hydrogen storage. Our approach involved performing a substantial number of Monte Carlo steps (10,000) to ensure system equilibration and precise results. We defined a cutoff distance for particle interactions as 12.5 Ǻ and considered 0.000e framework charge per cell and 0.000e sorbate charge in energy calculations. The choice of an appropriate simulation cell size (50 × 50 × 50) Ǻ was crucial, mirroring real-world conditions. We specified lower and upper fugacity values (1 to 10 atm) to capture the range of gas pressures in the simulations. These methodical steps collectively enabled us to accurately model hydrogen adsorption within zeolites, forming the core of our hydrogen storage evaluation. In this research, we utilized DFT calculations to thoroughly investigate the interactions between zeolites and hydrogen. We employed pseudopotentials to describe electron behavior in zeolite systems, choosing them in line with DFT norms and basis set compatibility. Our simulation cell design replicated zeolite periodicity and eliminated boundary effects. Pre-geometry optimization was performed with HyperChem29, ensuring stable conformations with strict convergence criteria. We utilized 6-31 + G(d) and LanL2DZ basis sets for light and heavy atoms, aligning with field standards for computational efficiency and precision. A machine learning algorithm was used to rank the importance of various structural features such as mass (M), density (D), helium void fraction (HVF), accessible pore volume (APV), gravimetric surface area (GSA), and largest overall cavity diameter (Di) and how they affect the capacity of the zeolites. Machine learning analysis was performed with the Scikit-learn library, an open-source Python tool. We employed a range of machine learning models, including SVMs, random forests, and neural networks, primarily for data analysis and feature extraction. Pearson correlation analysis, a classical statistical technique, was used to evaluate linear relationships between variables and assess the strength and direction of these relationships. It served as a complementary tool to understand the interplay of variables in our dataset, distinguishing it from machine learning algorithms. Further quantum chemical calculations were also performed to calculate the adsorption energy, global reactivity electronic descriptors, and natural bond orbital analysis in order to provide insights into the interaction of the zeolites with hydrogen. The simulations and data analysis were performed using BIOVIA material studio software, Gaussian, and Origin Pro software.

Mechanism by which a novel non-thiazolidinedione peroxisome proliferator-activated receptor gamma agonist, FK614, ameliorates insulin resistance in Zucker fatty rats

AIM

The aim of this study was to examine the mechanism by which a novel non-thiazolidinedione (TZD) peroxisome proliferator-activated receptor (PPAR) gamma agonist, FK614, ameliorates insulin resistance in Zucker fatty rats.

METHODS

FK614 (1, 3.2 or 10 mg/kg) and a TZD PPARgamma agonist, pioglitazone (1, 3.2 or 10 mg/kg), were orally administered to Zucker fatty rats (genetically obese and insulin resistant) once a day for 14 days, and an oral glucose tolerance test was performed. The expression levels of various genes in the white adipose tissue (WAT) of Zucker fatty rats treated with FK614 (3.2 mg/kg), pioglitazone (10 mg/kg) and another TZD PPARgamma agonist, rosiglitazone (3.2 mg/kg), were determined using a real-time reverse transcription-polymerase chain reaction method. Morphometric analysis of the WAT of Zucker fatty rats treated with FK614 (3.2 mg/kg) and pioglitazone (10 mg/kg) was performed. Glucose transport activity in the isolated soleus muscle of FK614-treated Zucker fatty rats was also investigated.

RESULTS

FK614 and pioglitazone both improved glucose tolerance in Zucker fatty rats. FK614 significantly increased the expression levels of acyl CoA oxidase, a PPAR-responsive gene, and adipocyte fatty acid-binding protein (aP2), an adipocyte differentiation marker gene, in epididymal WAT. It also significantly decreased the level of gene expression of tumour necrosis factor-alpha, an insulin resistance-inducing factor in retroperitoneal WAT, as did pioglitazone and rosiglitazone. FK614 and pioglitazone both significantly increased the total number of adipocytes and decreased their average size in WAT, mainly by increasing the number of small adipocytes. Additionally, administration of FK614 to Zucker fatty rats enhanced insulin sensitivity for glucose uptake in the soleus muscle.

CONCLUSION

This study suggests the possibility that FK614 induces adipocyte differentiation in Zucker fatty rats by stimulating PPARgammain vivo, thereby changing the character of WAT and improving insulin sensitivity throughout the body.

Intravenous injection of oligodeoxynucleotides to the NF-kappaB binding site inhibits hepatic metastasis of M5076 reticulosarcoma in mice

We have developed synthetic double-stranded oligodeoxynucleotides (ODN) as 'decoy' cis elements that block the binding of nuclear factors to promoter regions of targeted genes, resulting in the inhibition of gene transactivation in vivo. In the present study, we employed decoy ODN targeting the transcription factor nuclear factor-kappaB (NF-kappaB) binding cis-elements to hepatic metastasis of murine reticulosarcoma M5076 in mice. Intravenous inoculation of M5076 into mice caused a marked increase in gene expression of interleukin-1beta, tumor necrosis factor-alpha and intercellular adhesion molecule-1 in the liver, whereas intravenous treatment with NF-kappaB decoy ODN reduced M5076-induced transactivation of these genes. Treatment with NF-kappaB decoy ODN, but not scrambled decoy ODN, significantly inhibited hepatic metastasis of M5076 in mice, and furthermore the combined treatment of NF-kappaB decoy ODN with an anti-cancer drug resulted in complete inhibition of hepatic metastasis in half of the mice, without affecting myelosuppression induced by the anti-cancer drug. Here, NF-kappaB decoy ODN inhibited hepatic metastasis of M5076 in mice possibly through a decrease in transactivation of important NF-kappaB-driven genes and also potentiated the anti-metastatic effect of an anti-cancer drug, demonstrating the first successful in vivo therapy for cancer metastasis using NF-kappaB decoy ODN as a novel molecular decoy approach.

Cachexia induction by EL-4 lymphoma in mice and possible involvement of impaired lipoprotein lipase activity

Several lines of evidence have postulated that reduction in the activity of lipoprotein lipase (LPL) is involved in cachexia induction in cancer patients. Recently we have demonstrated that murine melanoma B16 has the ability to reduce the LPL activity and thereby induce cachexia symptoms in mice following intraperitoneal inoculation. In order to further investigate the relationship between LPL activity and cachectic syndrome, cachexia models other than melanoma B16 are required. However, there are few animal cachexia models in which LPL activity is involved in the induction of cachectic symptoms. In this study, cachectic symptoms and plasma LPL activity were investigated in mice bearing EL-4 mouse lymphoma. In EL-4 bearing mice the body weight including tumor weight in the abdominal cavity was rather higher than that of normal mice without tumor, whereas weights of carcass wet and gastrocnemius muscle were significantly decreased in EL-4 bearing mice. Elevated blood levels of triglyceride and non-esterified fatty acid were observed in mice bearing EL-4, associated with the impaired plasma LPL activity. Overall, this study indicated that EL-4 lymphoma in mice results in a severe cachexia which is possibly related to impaired LPL activity and also provided a useful cachexia model for understanding the role of LPL in the development of cancer cachexia.

Ponalrestat, an aldose reductase inhibitor, inhibits cachexia syndrome in nude mice bearing human melanomas G361 and SEKI

Our recent study has demonstrated that ponalrestat, an aldose reductase inhibitor, activates lipoprotein lipase (LPL) activity in the adipose tissue and alleviates the cachectic symptoms induced by B16 melanoma in mice. In this study, the effect of ponalrestat on cachexia symptoms in nude mice bearing human melanomas G361 and SEKI was investigated because it has been suggested that the suppression of LPL has an important role in cachexia induction by these two melanomas in nude mice. Mice bearing G361 subcutaneously did not gain weight and became cachectic, associated with the tumor growth. Tumor growth was not affected by ponalrestat, nevertheless treatment with ponalrestat resulted in an amelioration of the reduction in the weight of body mass, epididymal fat, gastrocnemius muscle, carcass and whole body lipid induced by the presence of G361. A severe weight loss observed in nude mice bearing SEKI was also partially attenuated by ponalrestat treatment. Overall, this study showed that ponalrestat is effective in the attenuation of the cachectic symptoms induced by human melanomas G361 and SEKI in nude mice, suggesting that ponalrestat has a potential usefulness for the treatment of cancer cachexia.

Ponalrestat, an aldose reductase inhibitor, inhibits cachexia syndrome induced by colon26 adenocarcinoma in mice

Our recent study has demonstrated that ponalrestat, an aldose reductase inhibitor, activates lipoprotein lipase activity and alleviates B16 melanoma-induced cachexia in mice. In this study, the effect of ponalrestat on murine adenocarcinoma colon26-induced cachexia was investigated in mice. Mice bearing colon26 subcutaneously lost weight and became cachectic, associated with the tumor growth. Although tumor growth was slightly stimulated when tumor bearing mice were treated with ponalrestat: nevertheless, the drug attenuated the reduction in the weight of body mass, epididymal fat, gastrocnemius muscle and carcass induced by colon26, as well as significantly prolonged the survival of the colon26 bearing mice. Ponalrestat inhibited the production of interleukin-1 (IL-1) from human monocytes stimulated by Lipopolysaccharide (LPS) in vitro, and also suppressed LPS-induced increase of IL-1 in the blood in mice. Overall, this study showed that ponalrestat suppresses IL-1 production both in vitro and in vivo, and inhibits the cachectic symptoms induced by colon26 adenocarcinoma in mice, suggesting that ponalrestat has a therapeutic potential for the treatment of cancer cachexia.

Effects of a novel pyridylsulphonyl thiazole derivative, FR115092, on autoimmune and mitomycin C-induced thrombocytopenia in mice

Dapsone (4,4'-diaminodiphenyl sulphone), an antileprotic and antimalarial drug, has been reported to be of therapeutic benefit in idiopathic thrombocytopenic purpura in the clinic. However, adverse reactions such as haemolytic anaemia have often been observed. In this study, we found that dapsone increased the number of platelets and decreased the number of red blood cells in male (NZWxBXSB)F1 (W/BF1) mice, an animal model of idiopathic thrombocytopenic purpura. In studies to prepare derivatives of dapsone with weaker side effects than the parent compound, FR115092 (2-[5-(2-pyridylsulphonyl)thiazolyl]amine) was discovered. The effect of FR115092 on the number of blood cells was studied and compared with dapsone in mice. FR 115092 increased the number of platelets without reducing the number of red blood cells in W/BF1 mice. This drug significantly suppressed the increase in circulating autoantibodies against platelets and increased the number of megakaryocytes. Furthermore, FR115092 inhibited the reduction of the number of platelets in mitomycin C-induced thrombocytopenic mice, as a consequence of its enhancement of growth and maturation of megakaryocytes. These findings suggest that FR115092 may be effective against various thrombocytopenias, without inducing haemolytic anaemia.

Activation of lipoprotein lipase and inhibition of B16 melanoma-induced cachexia in mice by ponalrestat, an aldose reductase inhibitor

Lipoprotein lipase (LPL) is a key regulatory enzyme responsible for the hydrolysis of triglyceride (TG)-rich lipoproteins. The reduction in LPL activity is observed in tumor bearing animals and cancer patients with cachectic symptoms, suggesting an involvement of LPL in inducing cancer cachexia. During a screening program for anti-cachectic agents we found that ponalrestat, an aldose reductase inhibitor, activates LPL activity. Ponalrestat increased the activity of LPL in adipose tissue in mice. The effect of ponalrestat on B16 melanoma-induced cachectic symptoms was next investigated in mice. The decrease in the weight of epididymal fat, carcass and whole body lipid was observed in mice following intraperitoneal inoculation of B16, compared to mice without the tumor inoculation. Treatment with ponalrestat resulted in the attenuation of the decrease in the tissue weight. The increase in the levels of TG and non-esterified fatty acid, and a decrease in the level of glucose in the blood, which was induced by the presence of tumor, were also restored to those of normal mice following ponalrestat treatment. The reduction in locomotor activity in tumor bearing mice was partially restored by the treatment with ponalrestat. Overall, this study demonstrated that ponalrestat, an aldose reductase inhibitor, possesses potent LPL activating activity and that the cachexia induced by B16 melanoma was alleviated by treatment with 'ponalrestat, suggesting that ponalrestat, a LPL activating agent, has a therapeutic potential for the treatment of cancer cachexia.

Intratumoral injection of oligonucleotides to the NF kappa B binding site inhibits cachexia in a mouse tumor model

Cancer cachexia, characterized by anorexia, weight loss and progressive tissue wasting, has been postulated to be mediated by various cytokines. However, the precise mechanism of cachexia induction is not fully explained. We have developed synthetic double-stranded oligodeoxynucleotides (ODN) as 'decoy' cis-elements that block the binding of nuclear factors to promoter regions of targeted genes, resulting in the inhibition of gene transactivation in vivo as well as in vitro. This novel molecular strategy could be useful for treating a broad range of human diseases including cancer. In this study, we injected decoy ODN targeting the transcriptional factor, NF-kappa B (NF kappa B) binding cis-elements, which are essential for transactivation of gene expression of cytokines, directly into tumors of adenocarcinoma colon26 in mice, in order to examine whether or not cachexia is alleviated by inhibiting the action of cytokines. Tumor growth was not affected by transfection of NF kappa B decoy ODN as compared with scrambled decoy ODN. Nevertheless, transfection of NF kappa B decoy, but not scrambled decoy, ODN resulted in attenuation of the reductions in body weight, epididymal fat, gastrocnemius muscle mass and food intake, which were induced by the tumor presence. Interleukin 6 mRNA in the tumor was also markedly decreased by the transfection of NF kappa B decoy ODN. It is known that the transcriptional factor E2F plays a pivotal role in the coordinated transactivation of cell cycle regulatory genes. Therefore, we hypothesized that the introduction of synthetic double-stranded DNA with high affinity for E2F in vivo as 'decoy' cis-elements might inhibit the tumor growth of colon26, resulting in turn in inhibition of cachexia induction. However, injection of E2F decoy ODN failed to inhibit tumor growth and cachexia induction, as compared with mismatched decoy ODN. Overall, the present study demonstrated that cachexia induced by adenocarcinoma colon26 was inhibited by blocking of NF kappa B, using a novel molecular decoy strategy, without an effect on tumor growth, and also that tumor growth and cachexia induction in the colon26 model were not affected by E2F decoy ODN. These results suggest that cytokines regulated by NF kappa B may play a pivotal role in the induction of cachexia by colon26, providing a new therapeutic strategy for cancer cachexia.

Anti-cachectic effect of FK317, a novel anti-cancer agent, in colon26 and LX-1 models in mice

The effects of FK317 (11-acetyl-8-carbamoyloxymethyl-4-formyl-6- methoxy-14-oxa-1,11-diazatetracyclo[7.4.1.0(2, 7). 0(10, 2] tetradeca-2,4,6-trien-9-yl acetate), a novel anti-cancer agent, on murine adenocarcinoma colon26- and human lung carcinoma LX-1-induced cachexia were investigated in mice. Mice bearing colon26 or LX-1 s.c. lost weight and became cachectic, associated with tumor growth. FK317 and mitomycin C (MMC) inhibited the growth of both tumors. FK317 ameliorated the weight loss induced by the presence of colon26 or LX-1, while MMC enhanced it. An attenuation of the reduction in the weights of epididymal fat, gastrocnemius muscle and carcass was observed in FK317-treated tumor-bearing mice in both cachexia models, but not in MMC-treated mice. The decreases in the circulating levels of triglyceride, glucose and non-esterified fatty acid, which were induced by the presence of colon26, was partially inhibited by treatment with FK317. Overall, this study revealed that FK317 is a potent anti-cancer drug with anti-cachectic activity, suggesting that FK317 has potential utility for the treatment of cancer.

FK317, a novel substituted dihydrobenzoxazine, exhibits potent antitumor activity against human tumor xenografts in nude mice

The antitumor effects of FK317, a novel substituted dihydrobenzoxazine, were evaluated using human tumor xenografts (small cell lung cancer, non-small cell lung cancer, stomach cancer, colon cancer, pancreatic cancer, breast cancer, cervical cancer and ovarian cancer). Tumor growth-inhibitory effects and the effective dose-range of FK317 were much stronger and broader, respectively, than those of reference drugs such as mitomycin C, adriamycin, cisplatin, taxol and irinotecan. Furthermore, the body weight decrease and myelosuppression in FK317-treated mice were less than in the animals given any of the reference drugs. To explain this tumor selectivity, the distribution of FK317 was investigated after dosing tumor-bearing mice with the 14C-labelled compound. The concentration of FK317 in tumor tissues was relatively low, and long tumor retention was not observed. However, thin-layer chromatographic separation revealed that the radioactivity in the tumor resided mainly in strongly cytotoxic metabolites, while that in other tissues resided mainly in non-cytotoxic metabolites. These results suggest that FK317 shows strong antitumor activity without side effects, and one reason for this is its specific metabolite pattern. FK317 is now undergoing phase I clinical trials.

Different effects of FK317 on multidrug-resistant tumor in vivo and in vitro

FK317, a novel substituted dihydrobenzoxazine, was examined for antitumor effects on multidrug-resistant (MDR) tumor cells in vitro and in vivo. In nude mice, FK317 markedly inhibited the growth of s.c. implanted KB-V1 vinblastine (VLB)-resistant human epidermal carcinoma KB cells, as well as the parent cells (KB-3-1). However, KB-V1 showed much greater resistance to FK317 than to VLB and adriamycin (ADM) in the in vitro study. This resistance was reversed by the addition of verapamil, whereby intracellular accumulation of FK317 in the KB-V1 cells was also decreased. After incubation of FK317 in human and mouse blood, it was shown to be rapidly metabolized to a monodeacetylated form, and slowly metabolized further to a dideacetylated form. With the removal of the acetyl groups from FK317, resistance indexes in KB-V1 and SBC-3/ADM, ADM-resistant human lung carcinoma, decreased. In addition, photolabeling of P-glycoprotein with [3H]azidopine in KB-V1 plasma membrane was completely inhibited by FK317, but not by the deacetylated metabolites. These results indicate that FK317 is metabolized to deacetylated forms, which do not bind to P-glycoprotein and are incorporated into MDR cells, causing cytotoxic effects.

Synthesis and effects of novel thiazole derivatives against thrombocytopenia

5-(2-Pyridylsulfonyl)-2-thiazolamine (2) was effective both in mitomycin C (MMC)-induced thrombocytopenia and in an animal model of idiopathic thrombocytopenic purpura (ITP). It also suppressed the increase of autoantibodies against platelets in the ITP model and showed no blood toxicity. Chemical modification of 2 led to the discovery of more potent compounds against MMC-induced thrombocytopenia.

FK317: a novel substituted dihydrobenzoxazine with potent antitumor activity which does not induce vascular leak syndrome

PURPOSE

FK973, a substituted dihydrobenzoxazine, is an antitumor antibiotic which has shown high therapeutic efficacy in a phase I study, but its development has been abandoned because of the side effect of vascular leak syndrome (VLS) in the clinical study. This study was performed to investigate whether or not FK317, a new benzmethoxy derivative of FK973, retains the antitumor activity of FK973 without the side effect of VLS.

METHODS

VLS was evaluated by the volume of pleural effusion in rats. Cytotoxic activities were determined by a tetrazolium-based colorimetric assay (MTT assay) against murine (B16, P388) and human (HeLa S3, KB) tumor cell lines. Antitumor activities against murine ascitic leukemia (P388, L1210), murine solid tumors (reticulum cell sarcoma M5076, Colon 38 carcinoma) and human xenografts (mammary carcinoma MX-1, lung carcinoma LX-1) were examined.

RESULTS

FK973 (1.8 mg/kg) given i.v. to rats induced pleural effusion, one of the elements of VLS, 36 days after the first dosing, but did not 28 days after dosing. This model reflects clinical VLS delayed-type effusion with high protein concentrations. In contrast, FK317 (1.0-3.2 mg/kg) did not induce pleural effusion at all. FK317 had stronger cytotoxic effects against in vitro cultured B16, P388, HeLa S3 and KB tumor cell lines, and in in vivo experiments, FK317 showed equivalent antitumor activity against P388, M5076 and MX-1, and more potent antitumor activity against L1210, Colon 38 and LX-1 compared with FK973.

CONCLUSION

These results suggest that FK317 retains the antitumor activity of FK973 and does not induce VLS, and FK317 is a drug with high clinical potential for treating tumors in humans.

Cytotoxic mechanisms of FK317, a new class of bioreductive agent with potent antitumor activity

FK317 is a member of a new class of bioreductive agents that exhibit strong cytotoxicity against various human cancer cells. The effect of FK317 was found to be stronger than that of mitomycin C (MMC), adriamycin (ADR) or cisplatin (CDDP). Alkaline elution analysis indicated that FK317 formed interstrand DNA-DNA and DNA-protein cross-links in cells. On the other hand, no DNA single-strand breaks were observed in the cells treated with FK317. In a cell-free system the deacetylated metabolites produced cross-linked DNA under reductive conditions, though FK317 itself did not form DNA-DNA cross-links. In order to elucidate the metabolic activation mechanisms, we established an FK317-resistant subline from human non-small cell lung cancer cells (Lu99) by stepwise and brief exposure (1 h) to FK317. The resistant subline (Lu99/317) showed cross-resistance to MMC and carboquone (CQ), but not to ADR or CDDP. DT-diaphorase, which is one of the activation enzymes of MMC and CQ, was deficient in Lu99/317 cells as determined by enzyme activity assay. However, the levels of NADPH:cytochrome P450 reductase, which is another activation enzyme for MMC and CQ, were comparable in resistant and parent cell lines. Treatment of the cells with dicumarol, an inhibitor of DT-diaphorase, reduced the cytotoxicity of FK317 to Lu99 cells, but not to Lu99/317 cells. These results indicate that deacetylation of FK317 is necessary for its reductive activation, and deacetylated FK317 is reduced by DT-diaphorase to form an active metabolite, which produces DNA-DNA interstrand and DNA-protein cross-links that lead to cell death.

Discovery of FR115092: a novel antinephritic agent

A series of dapsone-related 4-aminopheynl and 2-aminothiazolyl derivatives was prepared, and their antinephritic activity and blood toxicity were evaluated. 5-(2-Pyridylsulfonyl)-2-thiazolamine (FR115092, 26) was effective against two nephritis models, namely graft-versus-host disease (GVHD) and autoimmune W/BF1 mice, and showed none of the blood toxicity observed with dapsone.

Effect of FR143430, a novel cytokine suppressive agent, on adenocarcinoma colon26-induced cachexia in mice

Cancer cachexia, characterized by weight loss and progressive tissue wasting, has been postulated to be mediated by cytokines. In this study the effect of FR143430, (2-(4-fluorophenyl)-4, 5, 6, 7-tetrahydro-3-(4-pyridyl)pyrazolo[1, 5-a]pyrimidine monohydrochloride), an inhibitor of Interleukin-1 and Tumor necrosis factor-a (TNF- a), on adenocarcinoma colon26-induced cachexia was investigated in mice. Tumor growth was not affected. Nevertheless, treatment with FR143430 (0.1 to lmg) into the tumor resulted in the attenuation of the reduction in body weight, food intake, epididymal fat and carcass weight, the decrease in the circulating levels of triglyceride and glucose, and the increase in the circulating levels of total cholesterol, non esterified free fatty acid (NEFA) and total protein, which were induced by the presence of the tumor. However, oral treatment with FR143430 failed to show an inhibitory effect on cachexia induction. Overall, this study demonstrated that the cachexia induced by colon26 was alleviated by the injection of FR143430 into the tumor in sufficient quantity, without any effect on tumor growth, suggesting the potential utility of cytokine suppressive agents e for the treatment of cancer cachexia.

Effects of a new non-steroidal 5 alpha-reductase inhibitor, FK143, on the prostate gland in beagle dogs

FK143 (4-[3-[3-[bis(4-isobutylphenyl)methylamino]benzoyl]-1H-indol-1-yl] - butyric acid) is a new non-steroidal inhibitor of steroid 5 alpha-reductase (5 alpha-reductase). The effects of FK143 on prostate size and histopathology of mature male beagle dogs were investigated and compared with those of finasteride (a steroidal 5 alpha-reductase inhibitor), and allylestrenol and chlormadinone acetate (CMA) (androgen receptor antagonists). FK143 was orally administered to the dogs daily for 12 weeks. At doses of 10 and 32 mg/kg, FK143 significantly reduced prostate volume to about 60% of the initial value, and dogs treated with FK143 showed a dose-dependent glandular epithelial atrophy in the prostate. FK143 showed no abnormal changes in organ weights and histopathology of the adrenal, testis, pituitary and liver. The degree of prostate reduction in the dogs treated with FK143 (10 and 32 mg/kg) was almost the same as that by finasteride (1.0 mg/kg) and smaller than that by allylestrenol (10 mg/kg) or CMA (10 mg/kg). However, allylestrenol increased liver weights, and CMA increased liver and reduced adrenal weights. These results demonstrate that FK143 can decrease the volume of the dog prostate without any influence on other organs, and they suggest that FK143 is a good candidate for the treatment for benign prostatic hyperplasia.

Association of interleukin-6 in the cerebrospinal fluid during crisis of calf with ammoniated feed syndrome

Ammoniated feed syndrome (AFS) in cattle is a neurotoxic syndrome caused by feeding specific ammoniated forage. To clarify the pathophysiology of AFS, we examined the association of interleukin-6 (IL-6) in the brain. By feeding milk either from cows fed such ammoniated forage or milk added with 4-methyl-imidazole, newborn calves showed a neurotoxic crisis of hyperexcitability, ataxia, muscle tremor, circling, roaring, epileptoid seizure, sweating and marked fever response. Although these calves had no pathological lesions in the brain, we detected a rise in IL-6 in the cerebrospinal fluid (CSF). Tumor necrosis factor-alpha (TNF-alpha) was not detected in the CSF. In the sera, IL-6 and TNF-alpha hardly changed during the experiment. Administration of recombinant human IL-6 into the lateral ventricle resulted in fever. Thus, we believe IL-6 in the CSF is related to the fever response in newborn calves with AFS.

Mechanism of growth inhibition by calpain inhibitor in MCF-7 cells

BACKGROUND

A calpain inhibitor, calpeptin, inhibited the cell growth of ER (estrogen receptor) positive breast cancer cells, such as MCF-7, T-47D, and ZR-75-1 in the presence of E2. The mechanism of this inhibition has not been clarified yet.

MATERIALS AND METHODS

MCF-7 cells were employed to investigate the mechanism of the inhibition. We studied the effect of calpeptin on the secretion of insulin-like growth factor-I (IGF-I) and transforming growth factor (TGF-alpha).

RESULTS

The secretion of IGF-I or TGF-alpha was not changed by calpeptin either in the presence or absence of E2. Moreover, the binding of IGF-I or TGF-alpha to MCF-7 cells augmented by the addition of E2 was not affected by calpeptin.

CONCLUSIONS

These results indicated that the inhibition of cell growth in MCF-7 by calpeptin was not due to the modulation of autocrine growth factors and their receptors.

New antitumor substances, FR901463, FR901464 and FR901465. II. Activities against experimental tumors in mice and mechanism of action

FR901463, FR901464 and FR901465, novel antitumor substances, were isolated from the fermentation broth of Pseudomonas sp. No. 2663. Their antitumor activities were examined in three mouse tumor systems and one human tumor system. The three FR compounds prolonged the life of mice bearing murine ascitic tumor P388 leukemia (T/C values were 160%, 145% and 127% for FR901463, FR901464 and FR901465, respectively), and inhibited the growth of a human solid tumor, A549 lung adenocarcinoma, with different effective dose ranges. FR901464 exhibited most prominent effects on these tumor systems among the three FR compounds. FR901464 also inhibited the growth of murine solid tumors, Colon 38 carcinoma and Meth A fibrosarcoma. To address the involvement of transcriptional activation ability of the three FR compounds in the antitumor effect, we selected FR901464 as a candidate compound and investigated cell cycle transition, chromatin status and endogenous gene expression in FR901464-treated tumor cells having elevated transcriptional activity. FR901464 induced characteristic G1 and G2/M phase arrest in the cell cycle and internucleosomal degradation of genomic DNA with the same kinetics as activation of SV40 promoter-dependent cellular transcription in M-8 tumor cells. In contrast to the potent activation of the viral promoter, FR901464 suppressed the transcription of some inducible endogenous genes but not house keeping genes in M-8 cells. These results suggest that FR901464 may induce a dynamic change of chromatin structure, giving rise to strong antitumor activity, and therefore may represent a new type of drug for cancer chemotherapy.

A new aromatase inhibitor, FR901537. II. Pharmacological and antitumor effects

The pharmacological and antitumor effects of FR901537, a new aromatase inhibitor, isolated from Bacillus sp. No. 3072, were studied. Treatment for four consecutive days with FR901537 inhibited the androstenedione-induced increase in the uterus weight in immature rats. FR901537 had no effect on the uterus, adrenal glands, ovary or pituitary weights in mature rats following 14 days of treatment. The antitumor activity of FR901537 on 7,12-dimethylbenz(a)anthracene-induced mammary tumors was studied in ovariectomized, testosterone propionate (TP)-treated rats as a postmenopausal tumor model. Ovariectomy caused the regression of the mammary tumors and the growth of tumors was remarkably stimulated following TP treatment. Further, in the rats treated with FR901537 and TP, the TP-induced tumor growth was significantly inhibited by FR901537. These results suggest that FR901537 is a promising drug in the treatment of estrogen-dependent mammary tumors in postmenopausal women.

Role of tissue factor in the antitumor effect of recombinant human tumor necrosis factor-alpha in mice

Recombinant tumor necrosis factor-alpha (rTNF-alpha) inhibited tumor growth of Meth A fibrosarcoma (Meth A) solid tumor in mice, and the antitumor effect of rTNF-alpha was significantly decreased by pretreatment with small doses or rTNF-alpha in mice. In in vitro experiments, incubation of human umbilical vein endothelial cells with rTNF-alpha enhanced procoagulant activity (PCA), which was drastically augmented after an addition of the conditioned medium of Meth A tumor cells. Furthermore, rTNF-alpha-induced PCA was decreased by pretreatment with rTNF-alpha in endothelial cells. This PCA was completely blocked after the addition of anti-human tissue factor (TF) murine monoclonal antibody. These results imply that in vivo antitumor effects of rTNF-alpha are mediated by expression of TF in endothelial cells, which is augmented by tumor released factor(s).

Potentiation of the toxicity of tumor necrosis factor by tumors in mice

Tumor necrosis factor-alpha (TNF-alpha) was reported to be important in the induction of septic shock. After i.v. injection of recombinant TNF-alpha (rTNF-alpha), BALB/c mice bearing Meth A fibrosarcoma (Meth A), but not normal mice, died of shock. Tumor cells are known to release many biological components. In this study, we examined the role of the tumor in the toxicity of rTNF-alpha in mice. Meth A cells maintained i.p. in mice were cultured for 24 hr in vitro. Conditioned medium (CM) obtained from the Meth A cells was given i.v. to mice, and 2 to 7 days later, i.v. injection of rTNF-alpha induced death in the animals. rTNF-alpha treatment 4 days after Meth A CM gave the maximum effect. rTNF-alpha did not induce death in mice treated with CM from spleen cells. However, after the Meth A cells were passaged 2 or 3 times in in vitro culture, the CM did not potentiate the toxicity of rTNF-alpha in mice. rTNF-alpha induced symptoms of disseminated intravascular coagulation (DIC) on coagulation parameters in the blood, and high plasma tissue factor (TF) activity in Meth A CM-treated mice and Meth A tumor-bearing mice. These results suggest that factor(s) are released from tumor cells activated by interaction with host cells, and injection of rTNF-alpha and the factor(s) results in the induction of DIC syndrome leading to host death.

Binding sites of droloxifene in the cytosol of 7,12-dimethylbenz[a]anthracene-induced rat mammary tumor cells

The binding sites, other than the estrogen receptor (ER), of the antiestrogens droloxifene (DROL, (E)-a-[p-[2-(dimethylamino)ethoxy]-phenyl]-a'-ethyl-3-stilbenol) and tamoxifen (TAM), and estradiol-17 beta (E2) in the cytosol of 7,12-dimethylbenz[a]anthracene-induced rat mammary ER-positive tumor cells were studied using a high-performance liquid chromatography (HPLC) gel filtration assay. The cytosol was incubated with 3H-labeled drug with or without unlabeled drug, and separated by HPLC gel filtration. 3H-E2 produced two major peaks of radioactivity at fractions No. 40 and No. 70. The peak at fraction No. 70 was identified as the ER in an ER-enzyme-immuno assay. This peak was dose-dependently inhibited by unlabeled DROL or TAM, DROL being a more potent inhibitor than TAM. The peak at fraction No. 40 was also inhibited by co-incubation with unlabeled DROL or TAM. 3H-DROL or 3H-TAM provided only one peak at fraction No. 43. This peak was thought to be an antiestrogen binding site (AEBS), because it was inhibited by unlabeled antiestrogen but not by E2. The results suggest that the antiestrogens DROL and TAM have a higher affinity for the AEBS than for the ER in the absence of E2, while in the presence of E2 both have an affinity for the ER and inhibit E2 binding to the ER.

The effect of droloxifene on the insulin-like growth factor-I-stimulated growth of breast cancer cells

Insulin-like growth factor-I (IGF-I) is an important mitogen in breast cancer. We studied here the effects of a new antiestrogen drug, droloxifene (DROL, (E)-alpha-[p-[2-(dimethylamino) ethoxy]-phenyl]-alpha'-ethyl-3-stilbenol) and tamoxifen (TAM) on the IGF-I-stimulated growth of estrogen receptor (ER) positive breast cancer cells, MCF-7 and their mechanism of action. IGF-I secretion from MCF-7 was increased by the addition of estrogen. Externally added IGF-I stimulated the growth of MCF-7 but not ER negative breast cancer cells, MDA-MB-231. DROL and TAM inhibited the IGF-I-stimulated growth of MCF-7. A 2 hr treatment with both drugs did not block IGF-I binding to the receptors in MCF-7. However, a 4 day treatment with DROL decreased the number of IGF-I receptors without altering the binding affinity in MCF-7. These results suggest that DROL can exert its antitumor activity against ER positive breast cancer not only by blocking the E2 binding to the ER, but also by counteracting the mitogenic effect of IGF-I.

FR901228, a novel antitumor bicyclic depsipeptide produced by Chromobacterium violaceum No. 968. III. Antitumor activities on experimental tumors in mice

The antitumor activities of FR901228, (E)-(1S,4S,10S,21R)-7-[(Z)- ethylidene]-4,21-diisopropyl-2-oxa-12,13-dithia-5,8,20,23- tetraazabicyclo[8,7,6]-tricos-16-ene-3,6,9,19,22-pentanone, isolated from Chromobacterium violaceum No. 968, were studied in animals. FR901228 (ip) prolonged the life of mice bearing such murine ascitic tumors as P388 and L1210 leukemias and B16 melanoma, and inhibited (iv) the growth of murine solid tumors (Colon 38 carcinoma, M5076 reticulum cell sarcoma and Meth A fibrosarcoma) and human solid tumors (Lu-65 and LC-6 lung carcinomas, and SC-6 stomach adenocarcinoma) implanted in normal and nude mice, respectively. Its antitumor activity was especially potent against murine Meth A fibrosarcoma and human SC-6 stomach adenocarcinoma which were refractory to mitomycin C or cisplatin. FR901228 also was more effective against mitomycin C-, cyclophosphamide-, vincristine- and 5-fluorouracil-resistant P388 leukemias than against non-resistant P388 in mice. These results suggest that FR901228 will be a new type of drug for the treatment of cancer.

The estrogenic and antiestrogenic activities of droloxifene in human breast cancers

The effects of a new antiestrogen, droloxifene (DROL, (E)-alpha-[p-[2-(dimethylamino)ethoxy]-phenyl]-alpha'-ethyl-3- stilbenol), on human breast cancer cells in vitro and in vivo were studied. Since phenol red has a binding affinity to the estrogen receptor (ER), we studied the activities of drugs in medium with or without this indicator. Estradiol-17 beta (E2) stimulated the growth of ER-positive breast cancer cells, MCF-7, ZR-75-1 and T-47D, in medium without phenol red, but not in medium containing this indicator. In medium without phenol red, DROL had no marked effects on the growth of MCF-7 and ZR-75-1, but slightly stimulated the growth of T-47D. Tamoxifen (TAM) stimulated the growth of these 3 cells. DROL dose-dependently inhibited the E2-induced stimulation of growth of these cells in medium without phenol red, but TAM inhibited the growth only at high concentrations. The growth of ER-negative breast cancer cells, MDA-MB-231, was not influenced by E2, DROL or TAM. DROL was more effective than TAM against ER-positive Br-10 breast carcinoma in nude mice, but neither drug had effects on ER-negative MX-1 breast carcinoma. These results suggest that DROL shows an antitumor effect on ER-positive breast cancers, being less estrogenic and more antiestrogenic than TAM.

The efficacy of combined treatment with recombinant human tumor necrosis factor-alpha and 5-fluorouracil is dependent on the development of capillaries in tumor

The antitumor effects of recombinant human tumor necrosis factor-alpha (rTNF-alpha) and 5-fluorouracil (5-FU) in combination treatment were examined on Meth A fibrosarcoma implanted intradermally in mice. Growth of the tumor was inhibited when rTNF-alpha was given i.v. on day 7 or 11 after implantation, but the effect was countered when 5-FU was additionally given i.p. once a day on days 1-4 after implantation. Conversely, 5-FU given on days 5-8 after implantation augmented the antitumor effects of rTNF-alpha. Injection of carbon particles showed that fine capillaries did not develop in the tumors of mice treated with 5-FU on days 1-4 after implantation, but that a delicate network of capillaries developed in the tumors of both the mice treated with 5-FU on days 5-8 after implantation and the controls given saline. The results show that the timing of 5-FU treatment is important when attempting to enhance the antitumor effects of rTNF-alpha, and suggest that these effects are directly associated with newly formed fine capillaries in the tumor.

Antiestrogenic and antitumor effects of droloxifene in experimental breast carcinoma

The pharmacological effects of droloxifene [E)-a [p-[2-(dimethylamino)ethoxy]phenyl]-a'-ethyl-3-stilbenol, FK435), a new antiestrogen drug, were studied and compared with those of tamoxifen in animals and in vitro cultured cells. Droloxifene showed about 20-fold and 3-fold higher affinity to estrogen receptors (ER) in the rat uterus and human ER positive MCF-7 breast carcinoma cells, respectively, than tamoxifen, and was more active in decreasing uterine weight of mature rats and 17 beta-estradiol-treated immature rats. Tamoxifen increased uterus growth in immature rats, but droloxifene did not, suggesting that droloxifene has no estrogenic effects. Both drugs inhibited the growth of in vitro cultured MCF-7 cells, with droloxifene being the more active agent, but this effect of both drugs was countered by 17 beta-estradiol. Neither drug, however, had effects on the in vitro growth of human ER negative MDA-MB-231 breast carcinoma cells. In vivo, both drugs inhibited the growth of MCF-7 carcinoma implanted subcutaneously in BALB/c nu/nu mice, but not the growth of human ER negative MX-1 breast carcinoma. The results suggest that droloxifene has antitumor effects on human ER positive breast cancers, and would be useful for the treatment of estrogen-dependent breast cancers.

Effect of FK973, a new antitumor antibiotic, on the cell cycle of L1210 cells in vitro

Our previous study showed that FK973 (11-acetyl-8-carbamoyloxymethyl-4-formyl-14-oxa-1,11- diazatetracyclo[7.4.1.0(2,7)0(10,12)]tetradeca-2,4,6-trien-6 ,9-diyl diacetate), a novel substituted dihydrobenzoxazine, which is a derivative of the fermentation product of Streptomyces sandaensis No. 6897, had strong antitumor effects on experimental tumors in vitro and in vivo. In this report, we investigated its effect on the cell cycle of murine leukemia L1210 cells in vitro by means of DNA/5-bromo-2'-deoxyuridine double staining and compared these effects with those of other antitumor drugs. Both FK973 and mitomycin C arrested the cells in the G2 phase. Vinblastine arrested the cells in the M phase and cytosine arabinoside, in the G1 phase. Although FK973 and mitomycin C were shown to act on the cell cycle in a similar way, FK973 was slower in producing its effect. From the results, FK973 arrests the cells in the G2 phase, and it appears that FK973 must be converted into the activated form in the cells for the development of its antitumor effects.

Important role of serotonin in the antitumor effects of recombinant human tumor necrosis factor-alpha in mice

The possible involvement of chemical mediator(s) in the induction of the antitumor effects of recombinant human tumor necrosis factor-alpha (rTNF-alpha) on Meth A fibrosarcoma (Meth A) in mice was studied. On day 7 after intradermal implantation of Meth A in mice, rTNF-alpha caused tumor necrosis and inhibited the tumor growth. Ketanserin, cyproheptadine, and spiperone [serotonin (5-HT) receptor blockers] inhibited or attenuated the antitumor effects of rTNF-alpha, but the other types of receptor blockers tested (histamine H1 and H2, adrenaline alpha and beta, dopamine, and acetylcholine receptor blockers) did not. The large i.v. doses of 5-HT caused tumor necrosis and inhibited tumor growth in mice when given i.v. on day 7 but not when given on day 3 after Meth A implantation, which effects closely resemble those of rTNF-alpha. Its anti-tumor effects were completely inhibited by the 5-HT receptor blockers. 5-HT, like rTNF-alpha, showed no cytotoxicity against in vitro cultured Meth A cells. The results suggest that 5-HT is, at least in part, important for the induction of antitumor effects of rTNF-alpha on Meth A in mice.

Antitumor activity and hematotoxicity of a new, substituted dihydrobenzoxazine, FK973, in mice

FK973, a new, substituted dihydrobenzoxazine (11-acetyl-8-carbamoyloxymethyl-4-formyl-14-oxa-1,11- diazatetracyclo[7.4.1.0.0]tetra-deca-2,4,6-trien-6,9-diyl diacetate), was obtained by chemical modification of a novel antibiotic which was isolated from the fermentation products of Streptomyces sandaensis No. 6897. FK973 had cytotoxic effects against in vitro cultured human and murine tumor cells. FK973 in doses of 0.032-5.6 mg/kg (i.p.) had stronger antitumor activities and higher chemotherapeutic ratio than mitomycin C against such murine ascitic tumors as P388 and L1210 leukemia, B16 melanoma, M5076 reticulum cell sarcoma of ovarian origin, Colon 26 carcinoma, Ehrlich carcinoma, and MH134 hepatoma. In tests against murine and human solid tumors implanted s.c. in normal mice and nude mice, respectively, FK973 (i.v.) inhibited growth of murine tumors (M5076 sarcoma, Colon 38 carcinoma, B16 melanoma, and Lewis lung carcinoma) by 66-100% and human tumors (LX-1 lung, MX-1 mammary, and SC-6 stomach carcinoma) by 84-99%. In studies with drug-resistant P388 leukemia, FK973 was also effective against vincristine-resistant P388, moderately effective against mitomycin C (MMC)- and adriamycin-resistant P388, and partially effective against cyclophosphamide-resistant P388 cells in mice. Leukopenic effects of FK973 and MMC in mice were comparable at doses which gave antitumor activity almost equally. FK973 had no effect on the numbers of platelets and red blood cells, whereas MMC markedly decreased both. FK973 decreased the numbers of colony forming units in spleen and in culture and the effect was less than that of MMC. Therefore, FK973 may give weaker myelosuppression than MMC. The results suggest that FK973 will be a beneficial drug for the treatment of cancer.

Recombinant human tumor necrosis factor-alpha: thrombus formation is a cause of anti-tumor activity

In a previous study we showed that recombinant human tumor necrosis factor-alpha (rTNF-alpha) has no cytolytic effect on Meth A fibrosarcoma cells in vitro but that it has a strong anti-tumor activity in vivo. In the present work, we define the in vivo mode of action of rTNF-alpha on solid-form Meth A fibrosarcoma implanted intradermally (i.d.) in mice. rTNF-alpha exhibited strong anti-tumor activity when given intravenously (i.v.) 7 or 10 days after tumor implantation, but not when given 3 days after implantation. Light and electron microscopy showed that rTNF-alpha impaired microcirculation by producing fibrin-like substances in newly formed microcapillaries in 7-day-old tumor tissue. An anti-coagulant, dicoumarol, abrogated the effect of rTNF-alpha. Injection of carbon particles showed that the development of capillaries in 7-day-old tumors was more extensive than in 3-day-old tumors, and suggested that the anti-tumor activity of rTNF-alpha depends upon a fully developed fine network of induced capillaries in the tumor. Electron microscopy showed that rTNF-alpha increases the number of primary and secondary lysosomes in the cytoplasm of 7-day-old tumor cells. The results suggest that rTNF-alpha selectively stems the blood flow in newly formed microcapillaries, eventually leading to autolysis of the tumor cells.

Recombinant human tumor necrosis factor-alpha: evidence of an indirect mode of antitumor activity

The antitumor activity of recombinant human tumor necrosis factor (rTNF-alpha) was examined on murine tumors in mice and in cultured cells in vitro. Mice were implanted intradermally with Meth A fibrosarcoma (Meth A) on day 0. rTNF-alpha caused tumor necrosis and inhibited the tumor growth when given i.v. on day 7 or 10, but not when given on day 3. When rTNF-alpha was given i.v. in doses of 0.1-3.2 micrograms/mouse twice a week for 3 weeks beginning on day 7 or 11, the growth of solid Meth A, Colon 26 adenocarcinoma, Colon 38 carcinoma, Sarcoma-180, and M5076 reticulum cell sarcoma tumors implanted s.c. or intradermally was markedly inhibited, and the life of the mice bearing these tumors, except M5076 reticulum cell sarcoma, was prolonged. The growth of Meth A implanted i.m. was also markedly inhibited by rTNF-alpha given i.v. However, the life of mice bearing i.p. Colon 26 adenocarcinoma, MH134 hepatoma, Sarcoma-180, and Ehrlich carcinoma was not prolonged by rTNF-alpha given i.p. nine times (days 1-9) in doses up to 1.0 or 3.2 micrograms/mouse. Only in the case of mice bearing i.p. Meth A, the life was slightly prolonged by i.p. treatment with rTNF-alpha but not by i.v. treatment. In experiments against in vitro cultured cells, rTNF-alpha did not show any direct cytotoxicity against mouse tumor cells: Meth A, Colon 26 adenocarcinoma, Colon 38 carcinoma, and Sarcoma-180, but had a cytotoxic effect against L929 mouse fibroblast. The results suggest that rTNF-alpha is a unique antitumor drug with potent necrotizing activity against solid tumors in mice, and that this activity may derive from indirect mechanisms related to the growth of tumors and not to the direct cytotoxicity of the drug.