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Drug resistance and toxicity are the most widespread limitations in the pursuit of sufficient antitumor effectiveness and successful control of oncological diseases, including colorectal cancer (CRC). Herein the objective was to investigate some hematological side effects of the chemotherapeutic regimen FOLFOX-4, their relation to dihydropyrimidine dehydrogenase (DPD) levels and the associated alterations in CRC patients' plasma free-radical scavenging properties and extent of oxidative molecular damage. Thirty-eight patients with histologically confirmed CRC diagnoses, assigned to chemotherapy with the FOLFOX-4 regimen, were recruited. The diagnostic methods included a complete physical examination, blood routine test and general biochemistry. The DPD levels were assayed. The patients' plasma free-radical scavenging properties and extent of molecular oxidative damage were determined by spectrophotometry and enhanced chemiluminescence. The clinico-pathological and demographics characteristics of the patients were in agreement with the reports from retrospective cohort studies. The FOLFOX-4 regimen induced a decrease in plasma free-radical scavenging properties and increased extent of lipid peroxidation. White blood cells, granulocytes and lymphocytes decreased significantly after the first cycle of the therapy. The patients' DPD level decreased statistically significantly in the case of severe reduction (more than 25%) of white blood cells and granulocyte counts. The obtained data are in agreement with already known facts concerning the side effects of the FOLFOX-4 regimen and associated changes in redox homeostasis. Genetic predisposition to effectively metabolize and tolerate the applied therapy, i.e. DPD levels, could modulate some aspects of the observed changes in the aforementioned parameters. [ABSTRACT FROM AUTHOR]

Based on the pharmacophore model of melatonin (MT 1) receptor, we recently synthesized a series of indole derivatives that showed anticonvulsant activity with low neurotoxicity and hepatotoxicity in rodents. In the present study, the three most potent C3-modified derivatives with hydrazine structure 3c , 3e , and 3f , with 2-chlorophenyl, 2-furyl, and 2-thienyl fragments, respectively, were selected, and their neurobiological activity was explored in mice. In Experiment #1, the dose-dependent anxiolytic effect of a single i.p. administration of the novel compounds at doses of 10, 30, and 60 mg/kg were studied in the open field (OF) test. In Experiment#2, the analgesic effect of 3c , 3e , and 3f (30–100 mg/kg) was tested in the hot plate test and formalin test. Experiment#3 was designed to assess the antidepressant-like activity of 3c , 3e , and 3f (10–60 mg/kg). The forced swimming test (FST) and tail suspension test (TST)-induced effect on markers of oxidative stress in the frontal cortex (FC), and the hippocampus was evaluated. Melatonin was used in the same doses as melatonin analogs in all three experiments as a positive control. Desipramine (10 mg/kg) was also applied as a control in the FST. The three melatonin analogs bearing hydrazide/hydrazone substitution at 3C of the indol scaffold demonstrated improved antidepressant-like activity compared to the melatonin. The tested substances are devoided of anxiolytic effects. The antioxidant activity of the melatonin analogs and analgesic potential is comparable to that of melatonin. The 3C substitution with hydrazide/hydrazone moiety substantially contributes to the antidepressant and antioxidant activity of the melatonin analogs. [ABSTRACT FROM AUTHOR]

We have recently identified several aroylhydrazone-based molecular hybrids with antiseizure activity. We aimed to investigate the analgesic activity of these molecules further. Male ICR mice were injected intraperitoneally with the tested substances or with the vehicle only (controls). We performed hot plate tests, formalin test and maximal electroshock (MES) test and further studied the cytokine proteome in the brain. In silico analysis was performed for prediction of the physicochemical parameters and activity. The furan-substituted aroylhydrazone-based 2H-chromene hybrid showed a significant increase of the latent time as compared with the baseline values (p <.05). Both the chlorine-substituted and the methyl-substituted aroylhydrazone-based coumarin derivatives significantly decreased the first phase of the formalin test (p <.05). We also found suppression of all the cytokines which were overexpressed in the model of acute seizures (MES test) and in the formalin paw test. The in silico model predicted hydroxymethylglutaryl coenzyme A synthetase 2 (HMGCS2) enhancer activity. Further testing is needed to confirm the mechanism of the potentially beneficial effects of the tested substances and to evaluate the toxicity and efficacy of the proposed molecules. [ABSTRACT FROM AUTHOR]

Epilepsy is one of most reported neurological disorders after migraine, stroke and Alzheimer's disease. Empiric clinical data reveal that seizures and epilepsy more likely affect men than women. The aim of present study was to investigate the effect of steroid adrenal and gonadal hormones on the intensity, dynamics and latency of kainic acid-evoked seizure and lethality in a rat model of epileptogenesis. After surgical adrenalectomy/gonadectomy, male rats wereat randomassorted in groups and treated from postoperative day 1 to day 5 with corticosterone (30 mg/kg), estradiol (0.03 mg/kg), progesterone (75 mg/kg), dihydroprogesterone (75 mg/kg) and dihydrotestosterone (0.75 mg/kg). Spontaneous recurrent seizures generated by kainic acid were assessed. The treatment with corticosterone eliminated the aggravation of kainic acid-evoked seizures produced by adrenalectomy/gonadectomy. The application of corticosterone decreased the seizure intensity by 31% and prevented seizure-associated animal death. The effect of estradiol treatment was quite opposite. Estradiol treatment exacerbated the somatic and behavioural aspects of kainic acid-evoked epilepsy-like syndrome. The hormone increased the intensity of kainic acid-evoked seizures by 31%, decreased the latency of clonic weak seizures by 49% and enhanced the associated lethality by 133%. The treatment with progesterone or dihydroprogesterone produced minor alterations in intensity and latency of kainic acid-evoked seizures in the operated male rats. The application of dihydrotestosterone significantly aggravated the kainic acid-evoked seizures. In summary, hormonal unbalance could play an important role for seizure susceptibility in epileptogenesis. Corticosterone has better anti-seizure activity than progesterone and testosterone has significant pro-convulsive activity. [ABSTRACT FROM PUBLISHER]

Pregabalin and gabapentin are amino-acid derivatives of gamma-aminobutyric acid. They have a high affinity to the α2δ protein in the central nervous system and both have been shown to be effective for neuropathic pain disorder. The aim of this study was to investigate the efficacy of gabapentin and pregabalin in animal models of neuropathic pain, and to correlate with clinical outcomes in patients with diabetic neuropathy. Gabapentin (60 mg/kg) and pregabalin (30 mg/kg) attenuate mechanical, tactile and heat hypersensitivity in rats with chronic constriction injury of the sciatic nerve and streptozotocin (STZ)-induced diabetes. There is no evidence that one of the drugs is superior to another at the different rat models and tests. In the incisional pain model, there was partial efficacy of gabapentin. Our clinical data suggest that relative to the baseline pain score, the treatment with pregabalin at doses of 300 mg/day or gabapentin at doses of 900 mg/day would be effective and well tolerated in patients diagnosed with moderate diabetic polyneuropathy. The study suggested that pregabalin may provide better analgesic outcomes than gabapentin on the sixth month of treatment. In conclusion, the comparative effects of gabapentinoids in animal models of neuropathic pain and neuropathic patients are suggestive of similar pathophysiological mechanisms being involved, but successful outcome is determined by a patient's individuality and the drug nature as well as the drug tolerability. [ABSTRACT FROM AUTHOR]

Several peptides, including penetratin and Tat, are known to translocate across the plasma membrane. Dynorphin opioid peptides are similar to cell-penetrating peptides in a high content of basic and hydrophobic amino acid residues. We demonstrate that dynorphin A and big dynorphin, consisting of dynorphins A and B, can penetrate into neurons and non-neuronal cells using confocal fluorescence microscopy/immunolabeling. The peptide distribution was characterized by cytoplasmic labeling with minimal signal in the cell nucleus and on the plasma membrane. Translocated peptides were associated with the endoplasmic reticulum but not with the Golgi apparatus or clathrin-coated endocytotic vesicles. Rapid entry of dynorphin A into the cytoplasm of live cells was revealed by fluorescence correlation spectroscopy. The translocation potential of dynorphin A was comparable with that of transportan-10, a prototypical cell-penetrating peptide. A central big dynorphin fragment, which retains all basic amino acids, and dynorphin B did not enter the cells. The latter two peptides interacted with negatively charged phospholipid vesicles similarly to big dynorphin and dynorphin A, suggesting that interactions of these peptides with phospholipids in the plasma membrane are not impaired. Translocation was not mediated via opioid receptors. The potential of dynorphins to penetrate into cells correlates with their ability to induce non-opioid effects in animals. Translocation across the plasma membrane may represent a previously unknown mechanism by which dynorphins can signal information to the cell interior. [ABSTRACT FROM AUTHOR]

Opioid and non-opioid effects of acute and chronic morphine administration on behaviour, cardiovascular responses, cell proliferation and apoptosis and nitric-oxide synthase (NOS) activity were studied in rats. A novel score-point scale was introduced to quantify the signs of opioid withdrawal syndrome. NOS inhibitor L-NAME (N G -nitro-L-arginine methyl ester) was applied to reveal the role of NOS/NO pathway in the modulation of morphine-induced in vivo and in vitro responses. The obtained data showed that chronic co-administration of L-NAME drastically attenuated naloxone-precipitated withdrawal syndrome and prevented the development of morphine tolerance to cardiovascular action of morphine. The apoptotic process was very much restricted by L-NAME supplementation of chronic morphine treatment, which resulted in few apoptotic cells, less low molecular weight genomic DNA and preservation of high molecular weight non-fragmented genomic DNA. The study provides new data for nitroxidergic modulation of opioid tolerance and dependence.

Treatment of osteoporosis remains a therapeutic challenge. The effect of Apium Nodiflorum extract on development of experimental osteoporosis, pain thresholds and carrageenan-induced inflammation has been studied in ovariectomized osteoporotic Wistar rats. After osteoporosis verification rats were randomized and received vehicle only, HPLC-standardized Apium extract (equal to 2.4 mg/kg Quercetin) or Genistein (2.5 mg/kg) for 8 weeks. To verify the effect of Apium on the development of osteoporosis, bone mineral density (BMD) and bone mineral content (BMC), bone histology and plasma levels of IL-6 and RANKL were measured 6 months after ovariectomy and 8 weeks after treatment with Apium extract or Genistein as comparator. Inflammatory hyperalgesia was induced by intraplantar injection of 1% Carrageenan. Apium extract and Genistein impeded the development of osteoporosis (significant differences were shown for BMC and BMD levels in drug vs. vehicle treated rats) and improved bone histology and histological score. Apium and Genistein decreased IL-6 level. Both treatments alleviated mechanical hyperalgesia, decreased exudative reaction and lowered inflammatory pain threshold. The results suggested that Apium extract could be an alternative therapy for post-menopausal osteoporosis.