Investigation of thiosemicarbazide free or within chitosan nanoparticles in a murine model of vulvovaginal candidiasis.

Vulvovaginal candidiasis is a serious health problem affecting numerous women around the world. Its treatment is based on antifungals which may not provide an effective cure because of the resistance presented by its etiological pathogens Candida spp. Candida albicans is the most prevalent species related to vulvovaginal candidiasis. Here, we evaluated the in vivo antifungal potential of thiosemicarbazide and thiosemicarbazide encapsulated within chitosan nanoparticles in a murine model of vulvovaginal candidiasis. The results demonstrated the antifungal capacity of free or nanoencapsulated thiosemicarbazide within chitosan to reduce the fungal load in the vaginal tissue of infected mice. In addition, histological analyses indicated the absence or a mild to moderate infection in thiosemicarbazide-treated groups. Statistical tests confirmed the existence of significant differences between the treated and the control groups. Therefore, our results suggest a potential application of thiosemicarbazide and encapsulated thiosemicarbazide as an alternative vulvovaginal candidiasis therapy.

Apoptotic mechanisms of N1-acetylacetone, N4-4-methoxy-salicylidene-thiosemicarbazide chelating with Nickel(II) on HL60 leukemia cells.

Thiosemicarbozone complexes that have a broad spectrum of biological activity are formed as a result of condensation reaction between thiosemicarbazide [H2N(C=S)-NH-NH2] and carbonyl-containing compounds. A new Nickel(II) complexes with N1-acetylacetone, N4-4-methoxy-salicylidene-thiosemicarbazidato ligand was synthesized and characterized. We studied the antileukemic activity of the Ni(II) thiosemicarbazone compound and assessed their potential for drug development. Specifically, the effects of this Ni(II) thiosemicarbazone compound on intracellular signal nodes and apoptotic pathways were investigated. According to our results, the Ni(II) thiosemicarbazone compound has apoptotic activity against HL60 cells. Moreover, while Ni(II) thiosemicarbazone compound significantly increased levels of p53 and cleaved caspase-3 proteins, it decreased level of Phospho-Akt1 protein in HL60 cells. The Ni(II) thiosemicarbazone compound could induce HL60 cell apoptosis through inhibiting of PI3K/Akt pathway. These results showed that Ni(II) thiosemicarbozone compound might be an antileukemic agent.

[Research of anti-inflammatory activity of the thiosemicarbaziden-morpholinilacetic acid].

Studying of synthesis and anti-inflammatory activity of a number of new derivatives of N-acylsubstituted of thiosemicarbazide and product of their heterocyclization (thiadiazole). In work the following reagents are used: hydrazide of N-morfolinilacetic acids, allil-, benzoil-, 4-brom-benzoil isothiocyanates. IR spectrums of compounds are removed on a spectrometer from Fourier converter by "AVATAR-320" in tablets with KBr, 1H NMR spectra were recorded on Bruker DRX500 spectrometer with a frequency of 500 MHz in DMSO-d6 solution relative to internal tetramethylsilane standard. X-ray diffraction analysis was carried out on four circuitous automatic diffractometer "Xcalibur". Mass spectra were recorded on a device FINNIGAN MAT.INCOS 50 direct input material with an ionization energy of 70 eV. Thin-layer chromatographic (TLC) analysis was performed on plates «Sorbfil¼ system benzene-isopropanol-ammonia 10:5:2, display iodine vapor. Melting point defined on the device «Boetius¼. Anti-inflammatory activity of compounds is studied on white not purebred rats. Statistical processing of results was carried out with use of the software package of "Statistica 6,0". The experimental results showed that, among the received new hydrazide derivatives of N-morpholinilacetyc acids are compounds (II-IV and VI), which have anti-inflammatory activity. It is possible that novel anti-inflammatory properties associated with their antibacterial properties due to the presence in their chemical structure and thiosemicarbazides 1,3,4-thiadiazol-2 (3H)-thione fragments. The obtained results allow us to recommend the test compounds for advanced pre-clinical trials to study their properties. Based on N-hydrazide morpholinil acetic acid, a number of new N-acyl-substituted derivatives of thiosemicarbazide is synthesized and described, composition and structure of which is proved by IR, 1H NMR spectroscopy and X-ray analysis. In an experimentation rats is founded anti-inflammatory activity of N-acyl-substituted thiosemicarbazide.

[Effect of semicarbazide on the peroxidation processes and Lewis carcinoma growth in mice].

Effects of various doses of semicarbazide on Lewis carcinoma metastasing and peroxidation processes in C57B1 mice have been investigated. In the animals with inoculated Lewis carcinoma, the semicarbazide in the dose of 1/120 LD50 had practical influence on the tumour growth and inhibited the metastasing into mice lungs (P < 0.05). Importantly, this dose significantly inhibited the formation of free radicals and active forms of oxygen against the background of decrease of the aldehydes level that was related to the acceptor properties of the drug.

Vascular adhesion protein-1 inhibition provides antiinflammatory protection after an intracerebral hemorrhagic stroke in mice.

The systemic immune response has a vital role in propagating the damage of an intracerebral hemorrhage (ICH). Vascular adhesion protein-1 (VAP-1), a semicarbazide (SCZ)-sensitive-amine-oxidase, was found in previous studies to have a role in migration of immune cells. In this study, we hypothesize that VAP-1 inhibition may decrease brain injury by attenuating the transmigration of immune cells to the injury site, and by doing so, reduce cerebral edema and improve neurobehavioral function in mice. Two VAP-1 inhibitors, LJP1586 and SCZ were given 1 hour after ICH induction by either collagenase or autologous blood injection. The VAP-1 siRNA, a VAP-1 gene silencer, and human recombinant AOC3 protein, a VAP-1 analogue, were delivered by intracerebroventricular injection. Postassessment included neurobehavioral testing, brain edema measurement, quantification of neutrophil infiltration and microglia/macrophage activation, and measurement of intercellular adhesion molecule-1 (ICAM-1), P-selectin, monocyte chemoattractant protein-1 (MCP-1), and tumor necrosis factor-α (TNF-α) expression 24 hours after ICH. We found that LJP1586 and SCZ reduced brain edema and neurobehavioral deficits 24 hours after ICH induction. These two drugs were also found to decrease levels of ICAM-1, MCP-1, TNF-α, and inhibit neutrophilic infiltration and microglia/macrophage activation. We conclude that VAP-1 inhibition provided antiinflammation effect by reducing adhesion molecule expression and immune cell infiltration after ICH.

Synthesis of some novel N4-(naphtha[1,2-d]thiazol-2-yl)semicarbazides as potential anticonvulsants.

A series of N(4)-(naphtha[1,2-d]thiazol-2-yl)semicarbazides were designed and synthesized to meet the structural requirements essential for anticonvulsant activity. Anticonvulsant activity was determined after intraperitoneal (i.p.) administration to mice by maximal electroshock (MES) and subcutaneous pentylenetetrazole (scPTZ)-induced seizure tests and minimal motor impairment was determined by rotorod test. A majority of the compounds exhibited significant anticonvulsant activity after intraperitoneal administration. Some of the selected compounds were evaluated orally in rats for activity in scPTZ test at several time points (50 mg/kg). The most active compounds carry bromo, fluoro and nitro substituents at 4-position in the phenyl ring. The biochemical estimations of malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) from brain homogenate not only clearly implicated the role of free radicals in PTZ-induced convulsion but also explained the possible mechanism of protective effect of semicarbazides, through the reduced formation of MDA and increased formation of SOD and GSH-Px.

Cyclization of thiosemicarbazide derivatives of 5-arylidene-2,4-dioxothiazolidine-3-acetic acids to 1,3,4-thiadiazoles and their pharmacological properties.

By the reaction of (5-arylidene-2,4-dioxothiazolidin-3-yl)acetyl chlorides with 4-phenylthiosemicarbazide, acylthiosemicarbazide derivatives 4-6 were obtained. The cyclization of 4-6 in acid medium led to 1,3,4-thiadiazole derivatives 7-9. The structure of the compounds was confirmed by elemental analysis and IR, H NMR, 13C NMR and MS spectra. The effects of compounds 7 and 9 on the central nervous system (CNS) of mice were studied.

Chemical-induced, nonlethal, developmental model of dissecting aortic aneurysm.

BACKGROUND: A chemical-induced, nonlethal, dissecting aortic aneurysm (DAA) is described following in utero exposure to semicarbazide, an inhibitor of the vascular enzyme semicarbazide sensitive amine oxidase (SSAO). METHODS: Sprague-Dawley rat dams were given semicarbazide (0.096-49.000 mg/kg/day) by IP injection on gestation days (GDs) 14-20, a period of rapid aortic development. Newborn rats (day 1) were killed and their thoracic organs were removed en bloc for near-serial cross sections and routine histopathology, Movat stain for elastin, and immunohistochemistry to differentiate cells involved in the evolution of the DAA. In subsequent experiments, pups from treated dams (0.096-6.125 mg/kg/day) were allowed to survive for 7 or 28 days. RESULTS: DAA occurred in nearly 100% of the rats at all doses except the lowest tested (1.530, 0.096 mg/kg/day). Dissections frequently extended to the carotids and, less frequently, to the abdominal aorta. Remodeling of vascular lesions proceeded by organization of collections of blood in vascular media (the "false lumen"), proliferation of vascular smooth muscle cells, fibrosis, and formation of irregular frayed elastic lamellae in healed vascular media. Biochemical quantitation and Western blot analysis of main extracellular matrix proteins on GD 20 showed no overt difference in expression of collagen type I, fibrillin-1, or elastin. CONCLUSION: This developmental model provides investigators an opportunity to explore the pathologic mechanisms of DAA and to examine the potential long-term effects of vascular remodeling of DAA.

Fos-like immunoreactivity in the brain associated with freezing or escape induced by inhibition of either glutamic acid decarboxylase or GABAA receptors in the dorsal periaqueductal gray.

GABAergic neurons exert tonic control over the neural substrates of aversion in the dorsal periaqueductal gray (dPAG). It has been shown that electrical stimulation of this region at freezing or escape thresholds activates different neural circuits in the brain. Since electrical stimulation activates cell bodies and fibers of passage, it is necessary to use chemical stimulation that activates only post-synaptic receptors. To investigate this issue further, reduction of GABA transmission was performed with local injections of either the GABA-A receptor antagonist bicuculline or the glutamic acid decarboxylase (GAD) inhibitor semicarbazide into the dorsolateral periaqueductal gray (dlPAG). Local infusions of semicarbazide (5.0 microg/0.2 microl) or bicuculline (40 ng/0.2 microl) into this region caused freezing and escape, respectively. The results obtained showed that freezing behavior induced by semicarbazide was associated with an increase in Fos expression in the laterodorsal nucleus of the thalamus (LD) and ventrolateral periaqueductal gray (vlPAG), while bicuculline-induced escape was related to widespread increase in Fos labeling, notably in the columns of the periaqueductal gray, hypothalamus nuclei, the central amygdaloid nucleus (Ce), the LD, the cuneiform nucleus (CnF) and the locus coeruleus (LC). Thus, the present data support the notion that freezing and escape behaviors induced by GABA blockade in the dlPAG are neurally segregated: freezing activates only structures that are mainly involved in sensory processing, and bicuculline-induced escape activates structures involved in both sensory processing and motor output of defensive behavior. Therefore, the freezing elicited by activation of dlPAG appears to be related to the acquisition of aversive information, whereas most brain structures involved in the defense reaction are recruited during escape.

Enhancement of acoustic evoked potentials and impairment of startle reflex induced by reduction of GABAergic control of the neural substrates of aversion in the inferior colliculus.

The neural network of the inferior colliculus (IC), implicated in the generation of defensive behavior to aversive acoustic stimuli, is under tonic GABAergic control. Dopamine also seems to have a modulatory role in these neural circuits. It is still unclear how such changes in transmission of acoustic information influence the motor expression of the defensive behavior. Startle reaction to a sudden noise has been used as an effective way to measure the motor reactivity of rats to fearful acoustic stimuli. In this work we examined the processing of sensorial information--assessed by the recording of auditory evoked potentials (AEP)--and the behavioral effects--evaluated by the freezing and startle responses--during the reduction of GABA levels caused by microinjections of semicarbazide (SMC, 6 microg/0.2 microl), a glutamic acid decarboxylase inhibitor, into the IC. These data were compared to the effects of the overall arousal elicited by apomorphine (APO, 0.5 mg/kg, i.p.). The results obtained show that IC microinjections of SMC induced freezing behavior, enhanced the AEP and impaired the startle reaction to a loud sound. On the other hand, APO changed neither the AEP nor the startle in the same experimental conditions. These results suggest that the release of GABAergic control of the neural substrates of aversion in the IC results in an increased processing of auditory information along with an inhibitory influence on the motor pathways responsible for the startle response.

Dorsolateral and ventral regions of the periaqueductal gray matter are involved in distinct types of fear.

Stepwise increases in the electrical stimulation of the dorsolateral periaqueductal gray (dlPAG) produces alertness, then freezing and finally escape. This paper examines whether this freezing is (i) caused by Pavlovian fear conditioning to the contextual cues present during stimulation and (ii) the result of the stimulation of neurons located inside the dlPAG or elsewhere. To this end, freezing behavior was assessed in rats exposed either to the same or a different environment (context shift test) following the application of either footshocks or stimulation of the dlPAG at the freezing threshold. Rats submitted to footshocks presented freezing to the context 24h later whereas rats submitted to the dlPAG stimulation showed freezing only immediately after the stimulation, regardless of the context. In the second experiment, aversive states generated by activation of the dlPAG were assessed either by measuring the thresholds for freezing and escape responses or the duration of these responses following microinjections of semicarbazide inside the dlPAG. The duration of freezing behavior was also measured in rats submitted to a contextual fear-conditioning paradigm using footshocks as unconditioned stimulus. Lesions of the ventral periaqueductal gray (vPAG) disrupted conditioned freezing to contextual cues associated to footshocks but vPAG lesions did not change the threshold of either freezing or escape responses elicited by electrical stimulation of the dlPAG. Lesions of the vPAG did not change the amount of freezing or escape responses produced by microinjections of semicarbazide into the dlPAG. These results indicate that stimulation of dlPAG neurons produce freezing behavior independent of any contextual fear conditioning and add to previously reported evidence showing that the vPAG is a critical structure for the expression of conditioned fear. In contrast, the neural substrate of unconditioned dlPAG stimulation-induced freezing is likely to elaborate unconditioned fear responses to impending danger, which have been implicated in panic disorder.

Influence of dietary osteolathyrogens on the eggshell quality of laying hens.

1. Laying hens were fed osteolathyrogens, either semicarbazide hydrochloride at 0.3 or 0.4 g/kg or beta-aminopropionitrile fumarate at 0.5 or 0.6 g/kg diet to examine their effects on eggshell quality. 2. Shell quality characteristics considered for evaluation were shell surface area, shell thickness, shell weight, percentage shell, shape index and the specific gravity of eggs. Measurement of shell quality traits revealed that the hens fed osteolathyrogens laid eggs with significantly lower specific gravities and proportion of shell by weight. These differences were not explained by differences in shell thickness or weight or the shape index of eggs. 3. It was concluded that osteolathyrogens cause hens to lay eggs with poor shell quality and such eggs are weak and fragile.

Existence of gamma-aminobutyric acid and its biosynthetic and metabolic enzymes in rat salivary glands.

To obtain more insight into the physiological role of gamma-aminobutyric acid (GABA) in rat salivary glands, we measured the concentration of GABA and the activities of its biosynthetic and metabolic enzymes, glutamate decarboxylase (GAD) and GABA transaminase (GABA-T). The GABA concentrations in rat parotid and submandibular glands were 10.0 and 14.3 nmol/g weight, respectively, which were 0.6-0.8% of the levels in the brain (cerebellum and medulla oblongata), whereas glutamic acid (Glu) was abundant in the two glands. These GABA levels in the two glands were significantly decreased by administration of semicarbazide (200 mg/kg, i.p.), a GAD inhibitor, and increased by gabaculine (50 mg/kg, i.p.), a GABA-T inhibitor. The activities of both GAD and GABA-T were also detected in homogenates of the two salivary glands, but they were lower than those in the brain. However, kinetic analysis showed that the values of Michaelis constants for Glu and GABA in both enzyme reactions in these two glands were similar to those in the brain. These results indicate that GABA and its biosynthetic and metabolic enzymes are present in rat salivary glands as well as the brain.

Some correlations between local anesthetic-induced convulsions and gamma-aminobutyric acid in rat spinal cord.

The effects of local anesthetics (procaine and lidocaine) on the gamma-aminobutyric acid (GABA) and L-glutamic acid (Glu) levels in rat spinal cord were studied during the convulsive process. The present study also investigated the influence of central GABA manipulations on the local anesthetic-induced convulsions. An increase in spinal GABA levels was observed at the preconvulsive and convulsive states after administration of procaine (170 mg/kg, i.p.) or lidocaine (120 mg/kg, i.p.), which induced clonic convulsions; in the depressive state, GABA levels returned to normal; in all states, Glu levels were unchanged. Semicarbazide (25-100 mg/kg, i.p.), a glutamic acid decarboxylase inhibitor, produced a decrease in spinal GABA content and strongly enhanced both local anesthetic-induced convulsions as shown by a shortening of the latency and an increase in the mortality. Aminooxyacetic acid (AOAA; 10-40 mg-kg, i.p.), a GABA transaminase inhibitor, dose-dependently increased spinal GABA content and markedly suppressed procaine-induced convulsions. However, lidocaine-induced convulsions were enhanced by AOAA. These results suggest that the spinal GABA neuron may respond to the convulsions induced by local anesthetics. Furthermore, there is a clear relationship between spinal GABA content and procaine-induced, but not lidocaine-induced, convulsions.

Flight behavior induced by microinjection of GABA antagonists into periventricular structures in detelencephalated rats.

Behavioral effects of unilateral microinjections into periventricular structures of bicuculline, a classic GABA-A antagonist, and semicarbazide, a glutamic acid decarboxylase blocker, were studied in detelencephalated rats. These drugs produced a behavioral activation together with jumps. However, the characteristics of this behavioral activation differed as the injections were made in dorsal periaqueductal gray matter or medial hypothalamus. These data show close similarities to those observed with intact animals suggesting that GABA-A receptors are involved in the neural control of expression of flight behavior and functions in an intact manner and possibly independent of influences from forebrain structures. At variance with intact animals, these drugs produced contralateral turning behavior when locally injected into MH, pointing to some kind of inhibitory control exerted by telencephalic structures on the expression of circling behavior from diencephalic regions.

Teratogenic effect of semicarbazide in Wistar rats.

Five groups of pregnant Wistar rats were injected intraperitoneally with a single dose of semicarbazide (SC) on day 5, 7, 10, 13, or 15 of gestation. The lots in each group received either 50, 75, 100 or 150 mg/kg SC. A sixth group received 17 mg/kg of the drug during the entire course of pregnancy. SC produced a significantly smaller number of live fetuses with respect to controls. This toxic effect after injection at days 7 and 10 of gestation was highest for all single doses. The mean of fetal weight decreased with respect to controls with almost all of the SC treatment studied. The number of implantations and live fetuses was significantly decreased in the rats receiving the continuous treatment. Most abnormalities in the 21-day-old fetuses were found in the brain, kidney, intestines and liver; skeletal anomalies were seen in the skull, sternum and ribs. SC also produced high postnatal mortality rates during the first month of life with the single doses as well as with the continuous treatment. Thus, SC produced signs of toxicity and/or teratogenic effects in rats with all doses administered.

[New evidence for a GABA-ergic component in the mechanism of action of benzodiazepine tranquilizers]. / Novye dokazatel'stva GAMK-ergicheskogo komponenta v mekhanizme deistviia benzdiazepinovykh trankvilizatorov.

Studies of impulse summation in the rabbit central nervous system have shown that valproate, an agent potentiating GABA-ergic inhibition, reduces while thiosemicarbazide and bicuculline that lower GABA inhibitory effects increase impulse summation. It has been also discovered that the action of phenazepam and diazepam is potentiated by valproate and reduced by thiosemicarbazide and bicuculline. According to the authors' data, diphenylhydantoin, an anticonvulsant having no GABA-positive effect fails to produce selective reduction of impulse summation. The data presented may be regarded as new evidence gained in the whole body for participation of the GABA-ergic mechanisms in the development of benzodiazepine effects.

[Effect of stimulants on the tranquilizing, hypnotic and myorelaxant action of phenazepam]. / Vliianie stimuliatorov na trankviliziruiushchee, snotvornoe i miorelaksantnoe deistvie fenazepama.

It has been established in experiments on mice and rats that sydnocarb, strychnine, corasol and thiosemicarbazide are correctors as regards the myorelaxant effect of phenazepam. The correcting effect of the drugs manifests to a greater degree under conditions of eliminating the side effects that developed. Electroencephalographic studies on the combined action of phenazepam and sydnocarb on the sleep cycles in rats have shown sydnocarb to reduce the hypnotic effect of the tranquilizer. Under conflict situation sydnocarb or strychnine exert no effect on the tranquilizing action of phenazepam. Conversely, corasol and thiosemicarbazide diminish the anxiolytic effect of the tranquilizer. The data obtained allowed one to recommend that sydnocarb and strychnine be introduced in medical practice as correctors of the side effects produced by phenazepam.

Convulsive seizure induced by intracerebral injection of semicarbazide (an anti-vitamin B6) in the mouse.

The direct injection of semicarbazide (SC), an antivitamin B6 (anti-B6), into the lateral ventricle of the mouse brain induced convulsion and tremors at a smaller dose after a shorter latent period than that in systemic administration. The symptoms were prevented by pyridoxine, aminooxyacetic acid or acetone, while they enhanced by pyridoxal, pyridoxal phosphate, or some other anti-B6. In mice fed a vitamin B6 (B6)-deficient diet, convulsion and tremors occurred at smaller doses of SC than those in mice given control food, and were counteracted by pyridoxine. On the other hand, mice into which SC had been injected in the neighboring site of the lambda first showed running fits, which was followed by convulsion and tremors.