Panx1 knockout promotes preneoplastic aberrant crypt foci development in a chemically induced model of mouse colon carcinogenesis.

Colorectal cancer, which is the third leading cause of cancer-related deaths worldwide, is a multistep disease, featuring preneoplastic aberrant crypt foci (ACF) as the early morphological manifestation. The roles of hemichannel-forming transmembrane Pannexin 1 (Panx1) protein have not been investigated in the context of colon carcinogenesis yet, although it has contrasting roles in other cancer types. Thus, this study was conducted to examine the effects of Panx1 knockout (Panx1-/- ) on the early events of chemically induced colon carcinogenesis in mouse. Wild type (WT) and Panx1-/- female C57BL6J mice were submitted to a chemically induced model of colon carcinogenesis by receiving six intraperitoneal administrations of 1,2-dimethylhydrazine (DMH) carcinogen. Animals were euthanized 8 h (week 7) or 30 weeks (week 37) after the last DMH administration in order to evaluate sub-acute colon toxicity outcomes or the burden of ACF, respectively. At week 7, Panx1 genetic ablation increased DMH-induced genotoxicity in peripheral blood cells, malondialdehyde levels in the colon, and apoptosis (cleaved caspase-3) in colonic crypts. Of note, at week 37, Panx1-/- animals showed an increase in aberrant crypts (AC), ACF mean number, and ACF multiplicity (AC per ACF) by 56%, 57% and 20%, respectively. In essence, our findings indicate that Panx1 genetic ablation promotes preneoplastic ACF development during chemically induced mouse colon carcinogenesis, and a protective role of Panx1 is postulated.

Road Less Traveled: Drug Hypersensitivity to Fluoroquinolones, Vancomycin, Tetracyclines, and Macrolides.

While fluoroquinolones, vancomycin, macrolides, and tetracyclines are generally safe antibiotics, they can induce both immediate and delayed hypersensitivity reactions (HSRs). Historically, less has been published on allergies to these antibiotics compared to beta lactams, but the prevalence of non-beta lactam HSRs is increasing. To fluoroquinolones, immediate HSRs are more common than delayed reactions. Both IgE and non-IgE mechanisms, such as the mast cell receptor Mas-related G protein-coupled receptor X2 (MRGPRX2), have been implicated in fluoroquinolone-induced anaphylaxis. Skin testing for fluoroquinolones is controversial, and the gold standard for diagnosis is a graded dose challenge. To vancomycin, the most common reaction is vancomycin infusion reaction (previously called "red man syndrome"), which is caused by infusion rate-dependent direct mast cell degranulation. Severity can range from flushing and pruritis to angioedema, bronchospasm, and hypotension that mimic type I HSRs. MRGPRX2 has been implicated in vancomycin infusion reactions. IgE-mediated HSRs to vancomycin are rare. Vancomycin skin testing yields high false positive rates. Thus, direct provocation challenge with slower infusion rate and/or antihistamine pre-treatment is preferred if symptoms are mild to moderate, and desensitization can be considered if symptoms are severe. To tetracyclines, non-IgE-mediated and delayed HSRs predominate with cutaneous reactions being the most common. There is no standardized skin testing for tetracyclines, and avoidance is generally recommended after a severe reaction because of the paucity of data for testing. Graded dose challenges and desensitizations can be considered for alternative or index tetracyclines if there are no alternatives. With macrolides, urticaria/angioedema is the most common immediate HSR, and rash is the most common delayed HSR. The predictive value for skin testing to macrolides is similarly poorly defined. In general, HSRs to fluroquinolones, vancomycin, macrolides, and tetracyclines are challenging to diagnose given the lack of validated skin testing and in vitro testing. Direct provocation challenge remains the gold standard for diagnosis, but the benefits of confirming an allergy may not outweigh the risk of a severe reaction. Skin testing, direct provocation challenge, and/or desensitization to the index non-beta lactam antibiotic or alternatives in its class may be reasonable approaches depending on the clinical context and patient preferences.

Nesfatin-130-59 Injected Intracerebroventricularly Increases Anxiety, Depression-Like Behavior, and Anhedonia in Normal Weight Rats.

Nesfatin-1 is a well-established anorexigenic peptide. Recent studies indicated an association between nesfatin-1 and anxiety/depression-like behavior. However, it is unclear whether this effect is retained in obesity. The aim was to investigate the effect of nesfatin-130-59-the active core of nesfatin-1-on anxiety and depression-like behavior in normal weight (NW) and diet-induced (DIO) obese rats. Male rats were intracerebroventricularly (ICV) cannulated and received nesfatin-130-59 (0.1, 0.3, or 0.9 nmol/rat) or vehicle 30 min before testing. Nesfatin-130-59 at a dose of 0.3 nmol reduced sucrose consumption in the sucrose preference test in NW rats compared to vehicle (⁻33%, p < 0.05), indicating depression-like/anhedonic behavior. This dose was used for all following experiments. Nesfatin-130-59 also reduced cookie intake during the novelty-induced hypophagia test (-62%, p < 0.05). Moreover, nesfatin-130-59 reduced the number of entries into the center zone in the open field test (-45%, p < 0.01) and the visits of open arms in the elevated zero maze test (-39%, p < 0.01) in NW rats indicating anxiety. Interestingly, DIO rats showed no behavioral alterations after the injection of nesfatin-130-59 (p > 0.05). These results indicate an implication of nesfatin-130-59 in the mediation of anxiety and depression-like behavior/anhedonia under normal weight conditions, while in DIO rats, a desensitization might occur.

Artemin promotes oncogenicity, metastasis and drug resistance in cancer cells.

Artemin (ARTN) is a member of glial cell line-derived neurotrophic factor (GDNF) family of ligands, and its signaling is mediated via a multi-component receptor complex including the glycosylphosphatidylinositol-anchored GDNF family receptors a (GFRa1, GFRa3) and RET receptor tyrosine kinase. The major mechanism of ARTN action is via binding to a non-signaling co-receptor. The major function of ARTN is to drive the molecule to induce migration and axonal projection from sympathetic neurons. It also promotes the survival, proliferation and neurite outgrowth of sympathetic neurons in vitro. ARTN triggers oncogenicity and metastasis by the activation of the AKT signaling pathway. Recent studies have reported that the expression of ARTN in hepatocellular carcinoma is associated with increased tumor size, quick relapse and shorter survival. Furthermore, ARTN promotes drug resistance such as antiestrogens, doxorubicin, fulvestrant, paclitaxel, tamoxifen and trastuzumab. Moreover, ARTN also stimulates the radio-therapeutic resistance. This review highlights the proposed roles of ARTN in cancer cells and discusses recent results supporting its emerging role as an oncogenic, metastatic and drug-resisting agent with a special focus on how these new insights may facilitate rational development of ARTN for targeted therapies in the future.

Immunization with DISC1 protein in an animal model of ADHD influences behavior and excitatory amino acids in prefrontal cortex and striatum.

The Disrupted-in-schizophrenia 1 (DISC1) gene is involved in vulnerability to neuropsychiatric disorders. Naples high-excitability (NHE) rat model neuropsychiatric problems characterized by an unbalanced mesocortical dopamine system. Here, we assessed behavioral and neurochemical effects of immunization against multimeric rat DISC1 protein in adult NHE rats, an animal model of attention-deficit hyperactivity disorder and their Random-Bred (NRB) controls. Males of both lines received subcutaneous injections of vehicle (PB), adjuvant only (AD) or recombinant rat DISC1 protein purified from E. coli, suspended in AD (anti-DISC1) at age of 30, 45 and 60 postnatal days (pnd). At 75 pnd, the rats were exposed to a Làt maze and 2 days later to an Olton eight-arm radial maze, and horizontal (HA) and vertical activities (VA) were monitored. Non-selective (NSA) and selective spatial attention (SSA) were monitored in the Làt and in the Olton maze by duration of rearings and working memory, respectively. Post mortem neurochemistry in the prefrontal cortex (PFc), dorsal (DS) and ventral (VS) striatum of L-Glutamate, L-Aspartate and L-Leucine was performed. All immunized rats showed a clear humoral IgM (but not IgG) immune response against the immunogen, indicating that immunological self-tolerance to DISC1 can be overcome by immunization. NHE rats exhibited a higher unspecific IgM response to adjuvant, indicating an immunological abnormality. The sole anti-DISC1 immunization-specific behavioral in the NHE rats was an increased horizontal activity in the Làt maze. Adjuvant treatment increased vertical activity in both lines, but in the NRB controls it increased rearing and decreased horizontal activity. Liquid chromatography/tandem mass spectrometry analysis of soluble or membrane-trapped neurotransmitters aspartate, glutamate and leucine revealed increased soluble aspartate levels in the ventral striatum of NRB controls after anti-DISC1 immunization. Immune activation by adjuvant independent of simultaneous DISC1 immunization led to other specific changes in NHE and control NRB rats. In DISC1-immunized NHE rats, horizontal activity in Lat maze correlated with membrane-trapped glutamate in PFc and in the NRB rats, duration of rearing in Olton maze correlated with membrane-trapped glutamate in PFc and aspartate in dorsal striatum. In addition to non-specific immune activation (by AD), the postnatal anti-DISC1 immune treatment led to behavioral changes related to mechanisms of activity and attention and had influenced amino acids and synaptic markers in striatum and neocortex in the adult NHE as well as control animals.

Involvement of CART in estradiol-induced anorexia.

Since estradiol exercises inhibitory effect on food intake, we wanted to find out if this influence of estradiol is mediated by cocaine- and amphetamine-regulated transcript peptide (CART), a well established anorectic agent in the brain. Ovariectomized (OVX) rats, replaced with estradiol to produce estrous-phase like conditions, showed a significant decrease in food intake as compared with that in OVX controls. Intracerebroventricular (icv) administration of CART (0.5-1 µg/rat) to OVX rats, resulted in a dose-dependent reduction in the food intake. The lower dose (0.25 µg) had no effect, and was considered subeffective. In estradiol replaced OVX rats, CART at subeffective dose, further reduced food intake. However, CART failed to reduce food intake in estradiol replaced OVX rats pretreated with anti-estrogenic agent tamoxifen (3 mg/kg, subcutaneous). Administration of CART antibody (1:500 dilution/rat, i.c.v.) significantly attenuated estradiol-induced anorexia in the OVX rats. While estradiol replacement significantly increased CART-immunoreactivity in the cells/fibers of paraventricular nucleus (PVN) of OVX rats, fibers in the anteroventral periventricular nucleus (AVPV), and cells/fibers in the arcuate nucleus (ARC) showed considerable reduction. These changes were attenuated following concurrent injection of tamoxifen to the estradiol replaced OVX rats. However, CART-immunoreactive cells/fibers in the periventricular area did not respond to any of the treatments. We suggest that estradiol treatment might influence the hypothalamic CART system in a site specific manner. While increased CART activity in the PVN might produce anorexia, reduction of CART in ARC and AVPV might represent a compensatory homeostatic response.

Biocompatibility of acellular nerves of different mammalian species for nerve tissue engineering.

To explore the biocompatibility of acellular nerves of different mammalian species, for the acellular nerves derived from rats and rabbits, the morphology, immunocompatibility, and cytocompatibility with bone marrow stromal cells (BMSCs) were evaluated. The results indicated that the tridimensional architecture and main proteins of endoneurial tubes in both biomaterials were well retained. The nerve scaffolds did not show immunogenicity or cytotoxicity, but facilitated growth of BMSCs and secretion of neurotrophic factors in vitro. In conclusion, acellular nerves of different species possess favorable biocompatibility, and xenogenic acellular nerves combined with BMSCs have potential to replace allografts for peripheral nerve reconstruction.

Relapse of experimental autoimmune encephalomyelitis after discontinuation of FTY720 (Fingolimod) treatment, but not after combination of FTY720 and pathogenic autoantigen.

FTY720 (Fingolimod) is known to have a significant therapeutic effect on experimental autoimmune encephalomyelitis (EAE). Here, we used an EAE mouse model, which had been established by immunizing C57BL/6J mice with a partial peptide of myelin oligodendrocyte glycoprotein (MOG35₋55), to examine the relapse of EAE upon discontinuation of treatment with FTY720 alone or in combination with MOG35₋55. Relapse was confirmed to occur in all animals (n=6) within one week after discontinuation of FTY720, with increase in the number of lymphocytes infiltrating the spinal cord and demyelination. However, in the case of combination therapy with FTY720 and MOG35₋55, relapse following discontinuation of treatment was completely suppressed. The autoantigenic peptide might serve to suppress the clonal selection of relapse-associated autoantigen-specific T cells.

Mouse H6 Homeobox 1 (Hmx1) mutations cause cranial abnormalities and reduced body mass.

BACKGROUND: The H6 homeobox genes Hmx1, Hmx2, and Hmx3 (also known as Nkx5-3; Nkx5-2 and Nkx5-1, respectively), compose a family within the NKL subclass of the ANTP class of homeobox genes. Hmx gene family expression is mostly limited to sensory organs, branchial (pharyngeal) arches, and the rostral part of the central nervous system. Targeted mutation of either Hmx2 or Hmx3 in mice disrupts the vestibular system. These tandemly duplicated genes have functional overlap as indicated by the loss of the entire vestibular system in double mutants. Mutants have not been described for Hmx1, the most divergent of the family. RESULTS: Dumbo (dmbo) is a semi-lethal mouse mutation that was recovered in a forward genetic mutagenesis screen. Mutants exhibit enlarged ear pinnae with a distinctive ventrolateral shift. Here, we report on the basis of this phenotype and other abnormalities in the mutant, and identify the causative mutation as being an allele of Hmx1. Examination of dumbo skulls revealed only subtle changes in cranial bone morphology, namely hyperplasia of the gonial bone and irregularities along the caudal border of the squamous temporal bone. Other nearby otic structures were unaffected. The semilethality of dmbo/dmbo mice was found to be ~40%, occured perinatally, and was associated with exencephaly. Surviving mutants of both sexes exhibited reduced body mass from ~3 days postpartum onwards. Most dumbo adults were microphthalmic. Recombinant animals and specific deletion-bearing mice were used to map the dumbo mutation to a 1.8 Mb region on Chromosome 5. DNA sequencing of genes in this region revealed a nonsense mutation in the first exon of H6 Homeobox 1 (Hmx1; also Nkx5-3). An independent spontaneous allele called misplaced ears (mpe) was also identified, confirming Hmx1 as the responsible mutant gene. CONCLUSION: The divergence of Hmx1 from its paralogs is reflected by different and diverse developmental roles exclusive of vestibular involvement. Additionally, these mutant Hmx1 alleles represent the first mouse models of a recently-discovered Oculo-Auricular syndrome caused by mutation of the orthologous human gene.

Nesfatin-1 increases anxiety- and fear-related behaviors in the rat.

RATIONALE: Nesfatin-1, derived from the protein NEFA/nucleobindin2 (NUCB2), is a newly identified peptide that acts as a potent satiety agent. It has been reported that peptides involved in the regulation of ingestive behavior are also involved in the regulation of the stress response. However, the relation between nesfatin-1 and stressor-related behaviors like anxiety and/or fear has not yet been investigated. OBJECTIVE: The effects of intracerebroventricular (ICV) injection of nesfatin-1 (0, 5, and 25 pmol/3 microl) were assessed in several paradigms that are thought to reflect anxiety and/or fear in rats. RESULTS: Consistent with an anxiogenic effect, nesfatin-1 dose-dependently decreased the percentage of time spent on the open arms of the elevated plus maze, increased latency to approach, and decreased consumption of a palatable snack in an anxiogenic (unfamiliar) environment. Moreover, ICV nesfatin-1 increased the fear-potentiated startle response and the time spent freezing to both context and conditioned cues in a conditioned emotional response test. CONCLUSIONS: These findings suggest that in addition to its role as a satiety peptide, nesfatin-1 may also be involved in the mediation of anxiety- and/or fear-related responses.

Symptom and quality of life results of an international randomised phase III study of adjuvant vaccination with Bec2/BCG in responding patients with limited disease small-cell lung cancer.

AIMS: This study reports the symptom and HRQOL results in which standard treatment was compared to standard therapy plus Bec2, an anti-idiotypic antibody that mimics GD3, a ganglioside antigen. METHODS: Five hundred and fifteen LD SCLC patients were randomised to receive five vaccinations of Bec2 (2.5mg)/BCG vaccine arm (VA) or an observational arm (OA) administered over a 10-week period. Survival was the primary end-point; HRQOL was a secondary end-point, assessed using the EORTC QLQ-C30/LC 13. RESULTS: There was no improvement in survival or progression-free survival in the vaccination arm. At baseline patients in both arms demonstrated significantly impaired scores on the global QOL scale, when compared to a normative population. However, HRQOL and symptom scores between the two treatment arms were not statistically different at any time point. CONCLUSION: We found no benefits to patient HRQOL by additional vaccination with Bec2/BCG to LD SCLC for patients who have been undergoing standard therapy.

Production of reactive oxygen species from aggregating proteins implicated in Alzheimer's disease, Parkinson's disease and other neurodegenerative diseases.

The deposition of abnormal protein fibrils is a prominent pathological feature of many different 'protein conformational' diseases, including some important neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), motor neurone disease and the 'prion' dementias. Some of the fibril-forming proteins or peptides associated with these diseases have been shown to be toxic to cells in culture. A clear understanding of the molecular mechanisms responsible for this toxicity should shed light on the probable link between protein deposition and cell loss in these diseases. In the case of the beta-amyloid (Abeta), which accumulates in the brain in AD, there is good evidence that the toxic mechanism involves the production of reactive oxygen species (ROS). By means of an electron spin resonance (ESR) spin-trapping method, we have shown recently that solutions of Abeta liberate readily detectable amounts of hydroxyl radicals upon incubation in vitro followed by the addition of small amounts of Fe(II). We have also obtained similar results with alpha-synuclein, which accumulates in Lewy bodies in PD. Our data suggest that hydrogen peroxide accumulates during Abeta or alpha-synuclein incubation and that this is subsequently converted to hydroxyl radicals, on addition of Fe (II), by Fenton's reaction. Consequently, we now support the idea that one of the fundamental molecular mechanisms underlying the pathogenesis of cell death in AD, PD, and possibly some other protein conformational diseases, could be the direct production of ROS during formation of the abnormal protein aggregates. This hypothesis suggests a novel approach to the therapy of this group of diseases.

Glial cell line-derived neurotrophic factor has a dose dependent influence on noise-induced hearing loss in the guinea pig cochlea.

We examined the effectiveness of glial cell line-derived neurotrophic factor (GDNF) to attenuate cochlear damage from intense noise stress. Subjects were exposed to 115 dB SPL one octave band noise centered at 4 kHz for 5 h. They received artificial perilymph with or without GDNF into the left scala tympani at 0.5 microliter/h from 4 days before noise exposure through 8 days following noise exposure. Different concentrations of GDNF (1 ng/ml, 10 ng/ml, 100 ng/ml, and 1 microgram/ml) were applied chronically directly into the guinea pig cochlea via a microcannula and osmotic pump. Noise-induced hearing loss was assessed with pure tone auditory brainstem responses (at 2, 4, 8 and 20 kHz), measured prior to surgery, 1 day before noise exposure, and 7 days following noise exposure. Subjects were killed on day 8 following exposure for histological preparation and quantitative assessment of hair cell (HC) damage. A dose-dependent protective effect of GDNF on both sensory cell preservation and hearing function was found in the treated ears. At 1 ng/ml, GDNF showed no significant protection; at 10 ng/ml, GDNF showed significant HC protection; and at 100ng/ml, it was greater and bilateral. At 1 microgram/ml, GDNF appeared to have a toxic effect under noise stress in some cochleae. These findings indicate that GDNF at certain concentrations can effectively protect the inner ear from noise-induced hearing loss.

Chronic intracerebroventricular administration of recombinant CART(42-89) peptide inhibits and causes weight loss in lean and obese Zucker (fa/fa) rats.

OBJECTIVE: Hypothalamic neuropeptide CART (cocaine-amphetamine-regulated transcript) is a leptin-dependent endogenous satiety factor in the rat, and single central injections of recombinant CART(42-89) lowers food intake in rats and mice. To assess the potential role of CART as a long-term regulator of food intake, we investigated the effects of continuous infusion of recombinant CART(42-89) on food consumption and body weight. RESEARCH METHODS AND PROCEDURES: Two doses of CART(42-89) were tested: 12 or 4.8 microg/d. Adult male, both lean (+/?) and Zucker (fa/fa) obese, rats were equipped with intracerebroventricular cannulae in the right lateral ventricle. The cannulae were connected to subcutaneously placed osmotic mini-pumps. Pumps were filled with either CART(42-89) or vehicle (50 mM phosphate-buffered saline, pH 7.4). The pumps delivered a continuous infusion of CART(42-89) or vehicle, and food intake and body weight were followed for 10 days (12 microg/d) or 7 days (4.8 microg/d). Animals given the low dose had the pump removed on Day 7, and from half of the group, trunk blood was collected after decapitation, whereas the other half of the group had their mini-pumps removed and were followed for another 7 days before being decapitated. RESULTS: Animals receiving the high doses displayed overt motor disturbances, whereas the low dose was devoid of such behavioral side effects. Both doses significantly lowered food intake with maximal effect on days 3 to 5 of the infusion period. The high dose of CART decreased body weight of normal animals to 85% of initial weight at days 3 to 5, whereas the weight of Zucker (fa/fa) obese rats dropped to 95% of the initial weight. In animals receiving 4.8 microg/d, moderate effects on body weight were seen between days 4 and 6 of the treatment period, but soon after termination of the treatment animals regained lost weight. To assess the biological activity of the contents of the osmotic mini-pumps, the pumps were removed from the subcutaneous implantation site, and 5 microL of their contents were injected intracerebroventricularly to naive animals kept on a restricted feeding schedule. The content of pumps from animals receiving 4.8 microg/d of CART(42-89) potently inhibited food intake, confirming full biological activity despite being kept for 7 days at body temperature. DISCUSSION: Due to obvious effects on motor behavior, it is impossible with certainty to conclude that the observed effects on feeding and body weight are primary interference with satiety centers or secondary to effects on locomotor pathways. Also, the present experiments suggest that hypothalamic appetite-regulating neurons are subject to pharmacological desensitization upon prolonged exposure to CART peptide. The underlying mechanism of such desensitization is as yet unknown.

Therapeutic benefit of ciliary neurotrophic factor in progressive motor neuronopathy depends on the route of delivery.

Ciliary neurotrophic factor (CNTF) has demonstrated therapeutic effects in several mouse mutants with motoneuronal degeneration. However, the poor bioavailability and toxic side effects of recombinant CNTF protein have complicated its use in patients with amyotrophic lateral sclerosis. CNTF gene transfer strategies were developed but faced the question of whether CNTF should be delivered to motoneuron cell bodies or to their axons or muscle targets. To address this issue, we have used an adenoviral vector (AdCNTF) coding for a secretable form of CNTF and compared different routes of its administration in the mouse mutant progressive motor neuronopathy (pmn). Intramuscular, intravenous, and intracerebroventricular injections of AdCNTF or the control vector AdlacZ resulted in transgene expression in skeletal muscle fibers, hepatocytes, and ependymal cells, respectively, as determined by histochemistry and reverse transcription-polymerase chain reaction. AdCNTF intramuscularly treated and intravenously treated pmn mice showed a 25% increase in mean life span and a reduced degeneration of phrenic myelinated nerve fibers, which correlated with elevated CNTF serum bioactivities. In contrast, intracerebroventricular AdCNTF administration did not affect the mean life span or motor axonal degeneration of pmn mice. The differential efficacy of peripheral and central CNTF vector administrations might be of interest for future studies in human motor neuron diseases.

[Brain-derived growth factor: current aspects]. / Factor de crecimiento derivado del cerebro: aspectos de actualidad.

INTRODUCTION: The neurotrophins are a family of proteins which are closely related structurally and functionally and include nerve growth factor (NGF), brain derived nerve factor (BDNF) and neurotrophin-3 (NT-3), neurotrophin-4/5 (NT-4/5) and more recently neurotrophin-6 (NT-6). BDNF is one of the most important endogenous proteins for control of survival, growth and differentiation of certain neurone populations both in the peripheral and central nervous systems. DEVELOPMENT: The ARNmt of the BDNF is found in nearly all regions of the brain. The highest levels are those of the hippocampus and cerebral cortex. The large number of effects attributed to BDNF are probably due to the union of this protein to its specific receptor on the cell surface, which leads to the formation of a complex which enables transmission of the signal caused by activation of the specific neurone pathway. Since discovery, BDNF has been detected and/or measured by different methods from biological assay to the application of molecular biology techniques. These methods have permitted analysis of the biochemical characteristics of this factor and its behaviour in different tissues. CONCLUSIONS: In this paper we review the most relevant aspects of distribution, biological actions of BDNF on different neurone populations, its clinical usefulness in neurological disorders, routes of administration and side effects.

Systemic hemodynamic, neurohormonal, and renal effects of a steady-state infusion of human brain natriuretic peptide in patients with hemodynamically decompensated heart failure.

BACKGROUND: Human brain natriuretic peptide (hBNP) is a promising agent for the treatment of decompensated cardiac failure. However, the systemic hemodynamic, neurohormonal, and renal effects of hBNP have been incompletely studied in human heart failure. METHODS AND RESULTS: The effects of a continuous 4-hour infusion of hBNP were determined in 16 decompensated heart failure patients in an invasive, randomized, double-blind, placebo-controlled study. Patients were evaluated during three 4-hour study periods: baseline, treatment (placebo [n = 4] versus hBNP 0.025 or 0.05 microgram/kg/min [n = 12]), and post-treatment. Urinary volume losses were replaced hourly to separate the vasodilatory and diuretic effects of hBNP. Two patients in the hBNP group were excluded from the analysis because of adverse events. hBNP significantly (P < .001) reduced right atrial pressure and pulmonary capillary wedge pressure by approximately 30% and 40%, respectively. hBNP also significantly lowered systemic vascular resistance from 1722 +/- 139 to 1101 +/- 83 dynes.s.cm-5 (P < .05). These unloading effects of hBNP produced a 28% increase in cardiac index (P < .05) with no change in heart rate. Compared to placebo, hBNP decreased plasma norepinephrine and aldosterone. Renal hemodynamics were unaffected by hBNP; however, most patients were resistant to its natriuretic effect. CONCLUSIONS: 1) The predominant hemodynamic effects of hBNP were a decrease in cardiac preload and systemic vascular resistance. 2) hBNP also improved cardiac output without increasing heart rate. 3) Plasma norepinephrine and aldosterone levels decreased during hBNP infusion. 4) hBNP is pharmacologically active and has potential in the therapy for decompensated heart failure.

Intrathecal ciliary neurotrophic factor delivery for treatment of amyotrophic lateral sclerosis (phase I trial).

OBJECTIVE: This Phase I trial of ciliary neurotrophic factor (CNTF) delivered intrathecally for the treatment of patients with amyotrophic lateral sclerosis was designed to determine the safety of this new mode of administration as well as the pharmacokinetics and drug distribution. METHODS: CNTF was administered using a drug pump implanted into the lumbar subarachnoid space in each of four patients with amyotrophic lateral sclerosis. Escalating doses (0.4, 0.8, 1.6, 4, and 8 micrograms/h) were infused for 48 hours per week in 2-week cycles until the highest tolerated dose was achieved. Patients were observed for side effects, and standardized muscle and respiratory function tests were performed. Cerebrospinal fluid (CSF) levels of CNTF were determined using simultaneous lumbar and cervical taps. Plasma and CSF levels of antibodies, CSF cells and protein, and routine blood chemistries were monitored, as were weight and vital signs. RESULTS: Pharmacokinetic studies of four patients demonstrated that the distribution and clearance of recombinant human (rH)CNTF are similar to those of many small, water-soluble agents (morphine, baclofen, clonidine) and that the steady-state concentration of rHCNTF at the cervical level was 18 to 36% of that at the lumbar level. Lumbar CSF levels were in the range of 44 to 1230 ng/ml. Intrathecally administered rHCNTF had different adverse effects than the systemically delivered drug. With intrathecal administration, no asthenia, fever, chills, nausea, weight loss, increased cough, or sputum production was found. All patients who received rHCNTF intrathecally experienced dose-related CSF pleocytosis (primarily lymphocytic) and rises in protein levels. No clinical signs of meningeal irritation, such as stiff neck, photophobias, or nausea, were seen. However, one patient who had lumbar spinal stenosis developed severe burning and cramping leg pain. A second patient developed a severe headache and leg and back cramping. No abnormal clinical chemistry or hematological findings were encountered. Plasma levels of rHCNTF were below detection. Antibodies to rHCNTF were found in the systemic circulation of only one patient. The gradual decline in motor strength and performance of standard skills did not improve or worsen. CONCLUSIONS: In this first trial of a recombinant neurotrophic factor to be administered intrathecally by drug pump, the CNTF was well distributed along the spinal canal. Pain syndromes (headache, radicular pain) that were dose-related occurred in two patients, but systemic side effects, which had been observed with subcutaneous rHCNTF, did not occur. Intrathecal drug pump delivery of neurotrophic factors may be the most appropriate way in which to test the efficacy of these high-molecular weight proteins, because high CSF levels can be achieved without significant systemic side effects.