ß-lactam Structured, 4-(4-(Methylsulfonyl)phenyl)-1-pentyl-3-phenoxyazetidin-2-one: Selectively Targets Cancerous B Lymphocyte Mitochondria.

BACKGROUND: ß lactam-structured Cox-2 inhibitors, possesses anti-proliferative and anti-inflammatory effects. OBJECTIVE: In this research, the actions of a synthetic ß lactam-structured Cox-2 inhibitor with 4-(4- (Methylsulfonyl) phenyl)-1-pentyl-3-phenoxyazetidin-2-one on cellular viability of cancerous lymphoblast obtained from patients with acute lymphocytic leukemia (ALL) and normal lymphocytes obtained from healthy donors were compared. METHODS: % the cell viability of cancerouslymphoblasts and normal lymphocytes treated with ß lactam derivatives were assayed with MTT test. Early apoptosis and necrosis were detected by double staining of annexin V/ propidium iodide and activity of caspase 3 as the final mediator in apoptotic mode of cell death was evaluated by colorimetric assay. RESULTS: Our results showed that ß lactam derivatives inhibited the proliferation of cancerous lymphoblast but not normal lymphocytes in a concentration-dependent mode by inducing apoptosis. Treatment with ß lactam derivatives resulted in a rapid loss of mitochondrial trans-membrane potential and induction of reactive oxygen species (ROS) formation, and cytochrome c release in cytosol of mitochondria resulted in activation of procaspase-9 and formation of active apoptosome. CONCLUSION: These findings suggest that 4-(4-(Methylsulfonyl)phenyl)-1-pentyl-3-phenoxyazetidin-2-one as a ß lactam could induce ROS-mediated death signaling throughmitochondrial pathway that results in apoptosis in only cancerous lymphoblast cells. The stimulationof apoptosis by ß lactams may provide a pivotal mechanismfor their anticancer effect in acute lymphocytic leukemia cells.

Pharmacokinetics, pharmacodynamics, safety, and tolerability of hyzetimibe (HS-25) in healthy Chinese subjects.

Hyzetimibe (HS-25) is a new cholesterol absorption inhibitor. We performed the first-in-human study to assess the safety, tolerability, and pharmacokinetics (including the effect of food) and pharmacodynamics (effect on blood lipid level) following single (1, 3, 5, 10, 20, and 30 mg) and multiple (5, 10, and 20 mg) ascending-dose of hyzetimibe in healthy subjects. An increase of exposure (area under the plasma concentration-time curve and maximum plasma concentration) to hyzetimibe and hyzetimibe-glucuronide (HS-25M1) was observed in an approximately dose-proportional manner. A terminal half-life of approximately 21 hours was observed with doses ranging between 5 and 30 mg. Steady state was achieved by day 8 of once-daily dosing with 1.6- and 1.2-fold accumulation for hyzetimibe and hyzetimibe-glucuronide, respectively. Food did not have any effect on hyzetimibe and hyzetimibe-glucuronide exposure. Administration of hyzetimibe once daily for 10 days reduced the levels of low-density lipoprotein cholesterol levels in healthy subjects and these recovered after discontinuation of this drug. All of the adverse events were mild or moderate in severity, and the majority of them were unrelated to hyzetimibe, with no dose-dependent trends. These findings suggest that hyzetimibe could be a potential treatment for hypercholesterolemia.

Antimycobacterial and phototoxic evaluation of novel 6-fluoro/nitro-4-oxo-7-(sub)-4H-[1,3]thiazeto[3,2-a]quinoline-3-carboxylic acid.

Several newer 6-fluoro/nitro-4-oxo-7-(sub)-4H-[1,3]thiazeto[3,2-a]quinoline-3-carboxylic acids (10-11a-q) were synthesised from 3,4-difluoro aniline and 3-fluoro-4-nitro aniline by nine-step synthesis. The compounds were evaluated for in vitro and in vivo antimycobacterial activities against Mycobacterium tuberculosis H37Rv (MTB), multidrug-resistant M. tuberculosis (MDR-TB) and Mycobacterium smegmatis (MC2) as well as being tested for their ability to inhibit the supercoiling activity of DNA gyrase from M. smegmatis. Among the synthesised compounds, 7-(1,4-dioxa-8-azaspiro[4.5]dec-8-yl)-6-nitro-4-oxo-4H-[1,3]thiazeto[3,2-a]quinoline-3-carboxylic acid (11l) was found to be the most active compound in vitro, with minimum inhibitory concentrations (MICs) of 0.09 microM and <0.09 microM against MTB and MTR-TB, respectively. Compound 11l was found to be 4 times and >506 times more potent than isoniazid against MTB and MDR-TB, respectively. In the in vivo animal model, 11l decreased the bacterial load in lung and spleen tissues by 30% and 42%, respectively, at a dose of 50 mg/kg body weight.

Antihypertensive effect of CS-905, a novel dihydropyridine calcium blocker, in conscious hypertensive dogs.

CS-905, (+-)-3-(1-diphenylmethylazetidin-3-yl)5-isopropyl 2-amino-1,4-dihydro-6-methyl-4-(m-nitrophenyl)-3,5-pyridine-dicarboxy lat e, is a novel dihydropyridine calcium blocker. Both CS-905 and nicardipine, when administered orally, produced a dose-dependent fall of blood pressure in conscious perinephritic hypertensive dogs. Unlike the hypotensive effect of nicardipine, that of CS-905 has a gradual onset and is long-lasting, with little increase in the heart rate and plasma renin activity (PRA). The lack of both tachycardia and increase of PRA is probably mostly due to the slow onset of antihypertensive action following CS-905.

Central dopaminergic actions of YM-14673, a new TRH analogue, in rodents.

The effects of a new TRH analogue, YM-14673 (N alpha-[[(S)-4-oxo-2-azetidinyl]carbonyl]-L-histidyl-L-prolinamide dihydrate) on spontaneous movement, sniffing, climbing, licking, biting and circling behaviors were compared with those of TRH and methamphetamine, in rodents. YM-14673 in a dose of 1 mg/kg (i.p.) enhanced spontaneous motor activity in rats, and induced sniffing and climbing behaviors in mice. The licking and biting behaviors were not induced by administration of YM-14673 even in a high dose (30-100 mg/kg i.p.) to mice. In addition, ipsilateral circling did not follow the i.p. administration of YM-14673 in rats receiving cis-flupenthixol unilaterally into the striatum. YM-14673 was about 20-30 times more potent than TRH to induce sniffing and climbing behaviors and to increase spontaneous movement. The sniffing and climbing behaviors induced by administration of YM-14673 and TRH were antagonized by treatment with haloperidol and alpha-methyl-para-tyrosine (alpha-MT). Methamphetamine (0.5-10 mg/kg i.p.), unlike YM-14673, showed significant pharmacological effects in all behavioral experiments, so that the pharmacological profile of YM-14673 was different from that of methamphetamine. These results suggest that both YM-14673 and TRH induced behavioral changes, presumably due to facilitatory effects on the central dopaminergic system.

Effects of a new TRH analogue, YM-14673, on disturbance of passive avoidance learning in senescence-accelerated mice.

Effects of a new TRH analogue, YM-14673 (N alpha-[[(S)-4-oxo-2-azetidinyl]carbonyl]-L-histidyl-L-prolinamide dihydrate), on disturbance of passive avoidance behavior were observed in senescence-accelerated mice (SAM). Latency of step-through in SAM-P/8/Ta (SAM-P/8, senescence-prone substrain) was significantly shorter than that in SAM-R/1/Ta (SAM-R/1, senescence-resistant substrain). Successive oral administration of YM-14673 (1 and 10 mg/kg) and TRH (10 mg/kg) for 3 weeks prolonged the shortened latency of step-through. These results suggest that YM-14673 is more potent than TRH in antiamnesic activities.

Effects of a new analog of thyrotropin-releasing hormone, N alpha-[(S)-4-oxo-2-azetidinyl) carbonyl]-L-histidyl-L-prolinamide dehydrate (YM-14673) on spinal reflex potentials and flexor reflexes in spinalized rats.

Experiments were performed on spinalized rats, transected at the Cl level. The intravenous administration of TRH and its analog YM-14673 (N alpha-[(S)-4-oxo-2-azetidinyl) carbonyl]-L-histidyl-L-prolinamide dehydrate) produced marked increases in the amplitude of mono- and polysynaptic reflex potentials and those of the withdrawal flexor reflexes. The effects of YM-14673 were stronger and longer-lasting than those of TRH. The stimulant action of TRH and YM-14673 on the flexor reflexes was not antagonized by prazosin, chlorpromazine, haloperidol or cyproheptadine, suggesting no involvement of the release of catecholamines or serotonin in the stimulant effects of TRH and its analog. Therefore, YM-14673 may be beneficial for the treatment of several spinal motor neuron diseases.

Beneficial renal effects of CS-905, a novel dihydropyridine calcium blocker, in SHR.

CS-905 is a potent dihydropyridine calcium blocker that has a gradual and long-lasting antihypertensive action with little tachycardia in SHR. In this study, we investigated chronic and acute effects of CS-905 on renal functions in SHR. To examine the chronic effects, 23 week-old male SHR were treated with CS-905 (1 or 3 mg/kg/day, p.o.) or 0.3% CMC (carboxymethylcellulose). After the 15 week-treatment, the agent dose-relatedly lowered systolic blood pressure measured 24 hr after the final administration (184 +/- 2 and 173 +/- 3 mmHg at 1 and 3 mg/kg/day vs. 218 +/- 4 mmHg for the control group). Natriuresis and the reduction of urinary protein excretion were also observed in the CS-905 treated groups. Urinary NAG (N-acetyl-beta-D-glucosaminidase) activity tended to decrease, but not significantly. Histopathological changes observed in the SHR kidney were reduced by chronic treatment with CS-905. On a single oral administration in 38 week-old SHR, CS-905 caused natriuresis at a dose of 3 mg/kg, but did not affect urinary protein excretion and urinary NAG activity. These effects of CS-905 on renal functions may be beneficial in the treatment of hypertension.

Effects of a new TRH analogue, YM-14673, on spontaneous motor activity in rats.

The effects of a new TRH analogue, YM-14673 (N alpha-[[(S)-4-oxo-2-azetidinyl]carbonyl]-L-histidyl-L-prolinamide dihydrate) on spontaneous motor activity (SMA) were compared with those of TRH in rats. Intraperitoneal, oral and intracerebral administrations of YM-14673 caused a significant and dose-dependent increase in SMA. TRH also showed similar actions as YM-14673 did, except after oral dosing. These actions of YM-14673 were about 20-100 times more potent than those of TRH. Pretreatment with haloperidol, alpha-methyl-p-tyrosine (alpha-MT) and amino-oxyacetic acid (AOAA) but not atropine, inhibited the ability of both YM-14673 and TRH to increase SMA. Focal microinjection into the nucleus accumbens of both YM-14673 and TRH induced about 100 times more potent increases in SMA than similar injections into the dorsal striatum. It is suggested that YM-14673 possesses more potent facilitatory effects on SMA than TRH, and that these appear to be mediated mainly by the mesolimbic dopaminergic system rather than by the nigrostriatal one. Other possible mechanisms are also discussed.

Antihypertensive effects of CS-905, a novel dihydropyridine Ca++ channel blocker.

CS-905 is a novel dihydropyridine calcium blocker. A single oral administration of CS-905 or nicardipine at doses of 0.3-3.0 mg/kg produced a dose-dependent reduction of blood pressure in conscious SHR. CS-905, when administered orally in conscious SHR, was more than 3 times as potent as nicardipine. Unlike the hypotensive effect of nicardipine, that of CS-905 has a gradual onset and is long-lasting, with little increase in heart rate. An intravenous administration of CS-905 also produced a hypotension with a slow onset and long duration in SHR, but CS-905 was 3 times less potent than nicardipine by intravenous administration. This difference may be attributed to the first pass effect, which was associated with nicardipine but not with CS-905. The blood pressure lowering effects of CS-905 was most potent in DOCA-salt hypertensive rats, followed by SHR, RHR and normotensive rats, in this order. CS-905 is expected to be an antihypertensive agent that is effective on a once a day regimen in clinical settings.

Effects of a new analogue of thyrotropin-releasing hormone on pentobarbital-induced sleeping time in rodents.

The effects of a new analogue of TRH, YM-14673 (N-[[(S)-4-oxo-2-azetidinyl]carbonyl]-L-histidyl-L-prolinamide dihydrate) on pentobarbital-sleeping time were observed in comparison with those of TRH in rodents. The YM-14673 was administered intravenously, orally and intramuscularly. In all cases it reduced pentobarbital-sleeping time in rats and/or mice in a dose-dependent manner. The analeptic activity of YM-14673 was about 10 times greater than that of TRH. Analeptic action was also observed with successive intravenous injections of YM-14673, once daily for 5 and 14 days in mice, suggesting that the drug induced no tolerance. In addition, there was evidence that the pituitary-thyroid axis was not necessary for the analeptic effects of YM-14673. In particular, it was noted that hypophysectomy did not reduce the antagonism by YM-14673 of pentobarbital-induced sleep and intracerebrally administered YM-14673 produced analeptic actions in mice. Pretreatment with atropine and baclofen antagonized the ability of YM-14673 to reduce sleep, induced by pentobarbital in mice. However, the analeptic action of YM-14673 was not reduced by the administration of haloperidol and phentolamine. These results suggest that YM-14673 produced facilitatory effects on the central nervous system, independent of an effect on the pituitary gland, and that the antagonizing effects by YM-14673 on the actions of pentobarbital may be affected by activation of the central cholinergic system as well as by inhibition of the GABA-ergic system.

Effects of YM-14673, a new TRH analogue, on responses to morphine in rodents.

The influence of YM-14673 (N alpha-[[(S)-4-oxo-2-azetidinyl]-carbonyl]-L-histidyl-L-prolinamide dihydrate), a new thyrotropin releasing hormone (TRH) analogue, on morphine-induced hypothermia, development of cerebral ischemia and analgesia was investigated in rodents. YM-14673, in doses not affecting the normal rectal temperature, antagonized morphine-induced hypothermia in mice. Morphine-induced hypothermia was also antagonized by administration of TRH, in doses increasing normal rectal temperature. Morphine increased the appearance rate of convulsions in rats subjected to bilateral occlusion of the carotid artery. YM-14673, unlike TRH, reduced the appearance rate of convulsions increased by morphine in the ischemic rats. Morphine-induced analgesia measured by the hot plate method was not affected by both YM-14673 and TRH. Naloxone antagonized the effect of morphine in the 3 models. These results suggest that YM-14673 possesses physiological opioid antagonistic properties.

Effects of YM-14673, a new TRH analogue, on neurological deficits in rats with experimental cerebral hematoma.

Effects of YM-14673, a new thyrotropin-releasing hormone (TRH) analogue, on neurological deficits were observed in comparison with those of TRH and citidine diphosphate choline (CDP-choline) in rats with an experimental hematoma. Unilateral cerebral hematoma was prepared by injection of 0.25 ml of autologous blood into the region around capsula interna, putamen and caudate nucleus of the left cerebral hemisphere of the rats. The drug was administered once or multiple times a day immediately after the surgical operation for 7 days and measurement of neurological deficits was conducted every day for 7 days. Neurological deficits, such as hemiplegia, were observed maximally on the 3rd day after the operation and then gradually recovered in the saline-treated group. YM-14673 (0.1, 0.3 mg/kg i.p.) accelerated the recovery of neurological deficits. Single i.p. administration of TRH did not affect the neurological deficits; however, multiple administration (7 times a day for 7 days) of TRH accelerated the recovery of neurological deficits. CDP-choline, a cerebral metabolic enhancer, even in a dose of 300 mg/kg (i.p.) did not show any influence on neurological deficits. These results suggest that YM-14673 ameliorated neurological deficits in the cerebral hematoma models, presumably due to TRH-like activity. Possible mechanisms of the pharmacological actions of YM-14673 are also discussed.

Effects of a new thyrotropin-releasing hormone derivative on behavioral changes after focal cerebral ischemia in rats.

We observed the effects of a new thyrotropin-releasing hormone derivative, YM-14673 (N alpha-[[(S)-4-oxo-2-azetidinyl]carbonyl]-L-histidyl-L-prolinamide dihydrate), on behavioral changes in rats for 3 weeks after focal cerebral ischemia. Under halothane anesthesia, the left middle cerebral artery was occluded via a transretro-orbital approach. YM-14673 was administered just after the operation and once a day for 3 weeks. Neurologic deficits, including hemiplegia and abnormal posture, and disturbance of passive avoidance learning were present in solvent-treated control rats for the entire 3 weeks. YM-14673 at 0.1 or 0.3 mg/kg i.p. or 1 mg/kg p.o. significantly accelerated the recovery of neurologic deficits and ameliorated cognitive disturbance compared with the solvent-treated controls although the drug at 0.1 and 0.3 mg/kg i.p. did not influence the size of the ischemic infarct. YM-14673 mitigated the behavioral disturbances in this model of chronic focal cerebral ischemia. We also discuss the suitability of this model for the evaluation of drugs.

Effects of a new TRH analogue, YM-14673 on a passive avoidance test as a possible criterion of improvement in cognitive disturbance in rodents.

Effects of a new TRH analogue, YM-14673 (N alpha-[[(S)-4-oxo-2-azetidinyl]carbonyl]-L-histidyl-L-prolinamide dihydrate) on cognitive disturbance of passive avoidance response were studied in rodents in comparison with those of TRH and CDP-choline. The latency for entering from the illuminated into the dark compartments was shortened in anoxia and scopolamine-treated rats, cycloheximide-treated mice and cerebral ischemic gerbils. The shortened latency in these models was prolonged by administration of both YM-14673 and TRH in doses without effect on spontaneous movement. YM-14673 was about 10 times more potent than TRH in ameliorating the cognitive disturbance, whereas CDP-choline showed no influence on the learning ability. These results suggest that YM-14673 and TRH possess facilitatory effects on cerebral function and that YM-14673 was distinct from CDP-choline in pharmacological profile.

Induction of endothelial cell migration by proline analogs and its relevance to angiogenesis.

The proline analogs cis-4-hydroxy-L-proline, 3,4-dehydro-L-proline, and 2-azetidinecarboxylic acid induced increases in the migration rate of retinal capillary endothelial cells, aortal endothelial cells, corneal endothelial cells, aortal smooth muscle cells, and retinal pericytes. cis-4-hydroxy-D-proline did not. The optimal concentration for migration induction by any of the active agents was approximately 10(-5) M. At higher concentrations (5 x 10(-4) M) migration was not induced or was inhibited. When tested by subcutaneous implant assays in rabbits, cis-4-hydroxy-L-proline and 2-azetidinecarboxylic acid consistently elicited a marked angiogenic response. Whereas these compounds are known to modulate collagen synthesis and secretion, the concentrations at which they are effective inducers of migration suggest that they may have a more specific target than general collagen synthesis.

N-aryl 3-halogenated azetidin-2-ones and benzocarbacephems, inhibitors of beta-lactamases.

N-(3-Carboxy-6-methylphenyl)-3-fluoroazetidin-2-one and a series of related N-aryl-3-halo- and -3,3-dihaloazetidinones 3, in which the halo substituent is a fluorine or a bromine atom, were prepared by using the Wasserman procedure of cyclization of beta-bromopropionamides as a key step. Their affinities for the TEM-1 beta-lactamase were determined and compared with those of a series of tricyclic azetidinones, the benzocarbacephems 2, and known beta-lactamase inhibitors. The beta-lactams 2 and 3 behave as competitive inhibitors and not as substrates of the enzyme; neither halogen substitution (series 3) nor ring strain (series 2) induces enzymatic hydrolysis.

Antagonizing effects of YM-14673, a new TRH derivative, on behavioral and electroencephalographic changes in reserpinized animals.

Effects of YM-14673 (N alpha-[[S)-4-oxo-2-azetidinyl)-carbonyl]-L-histidyl-L-prolinamide dihydrate), a new TRH derivative, on reserpine-induced behavioural and electroencephalographic changes were observed in comparison with those of TRH. YM-14673 antagonized reserpine-induced hypothermia and decrease in convulsion threshold in mice. The number of PGO waves recorded from the lateral geniculate body was decreased by administration of YM-14673 in reserpinized cats. The anti-reserpine activity of intravenous YM-14673 was about 8-20 times more potent than that of TRH. In inhibiting reserpine-induced hypothermia, the oral ED2 degrees C relative to IV ED2 degrees C as an indirect indication of absorption rate of the drugs was 15 for both YM-14673 and TRH. These results suggest that YM-14673 possesses more potent facilitatory effects on the central monoamine systems than TRH.

Evidence for the combined involvement of serotonergic and alpha 2 adrenergic mechanisms in the analgesic activity of tazadolene succinate.

The analgesic activity of tazadolene succinate was assessed in mice and rats subsequent to pretreatment with various depletors and antagonists of monoamine neurotransmitters. In the mouse warm plate assay, reserpine was confirmed to cause a profound antagonism of tazadolene analgesia. However, yohimbine, Sch 23390 and haloperidol, antagonists of alpha 2 adrenergic, D1 dopaminergic and D2 dopaminergic receptors respectively, did not block tazadolene, nor did the serotonin depletor, p-chlorophenylalanine. But mice treated with both the depletor and yohimbine were significantly resistant to the analgesic effects of tazadolene. Combined treatments of haloperidol or prazosin (an alpha1 adrenergic antagonist) and p-chlorophenylalanine were not similarly effective. In the rat, reserpine blocked tazadolene analgesia in both the hot plate and air induced writhing assays. Likewise, combined treatment with yohimbine and p-chlorophenylalanine also antagonized the analgesia. These results confirm the monoamine dependence of tazadolene analgesia and indicate that both serotonergic and alpha 2 adrenergic mechanisms are involved. The results further suggest that these systems may be in parallel and integrated such that either one is capable of the primary expression of the analgesic effect of tazadolene. Thus, the unique analgesia properties of tazadolene are apparently due to the ability of this compound to activate both serotonergic and alpha 2 adrenergic antinociceptive systems.

Effects of a new TRH analogue, YM-14673 on the central nervous system.

The effects of a new TRH analogue, YM-14673 (N alpha-[[S)-4-oxo-2-azetidinyl)carbonyl]-L-histidyl-L-prolinamide dihydrate) on the central nervous system were compared with those of TRH. YM-14673 was 10-40 times more potent than TRH in antagonizing pentobarbital-induced sleep and hypothermia, and ethanol-induced hypothermia in mice. YM-14673 accelerated recovery from disturbed consciousness induced by concussive head trauma in mice and normalized the behavior and spontaneous EEG disturbed by electrolytic lesion of the hypothalamus in cats with 25-100 times greater potency than that of TRH. In the tests on pentobarbital sleeping time and EEG disturbance, the cerebral activating activity of YM-14673 was 8-36 times longer-lasting than that of TRH. These results indicate that YM-14673 possesses potent arousal effects on the central nervous system. The mode of action of YM-14673 was also discussed.