Long-term treatment of aged Long Evans rats with a dietary supplement containing neuroprotective peptides (N-PEP-12) to prevent brain aging: effects of three months daily treatment by oral gavage.

Aging is associated with morphological and functional changes in the brain, resulting in the deterioration of cognitive performance. Growth factors like BDNF are suggested to be involved in the regulation of age-related processes in the brain. A novel dietary supplement produced from purified nerve cell proteins, N-PEP-12, has shown to share properties with naturally occurring peptide growth factors by stimulating neurite outgrowth and beneficial effects on neuronal survival and protection against metabolic stress in cell cultures. The current study investigates the effects of long-term intake on age-dependent memory decline by assessing cognitive performance and synaptic density. All the experiments were performed in aged Long Evans rats randomly assigned to saline or N-PEP-12 once daily by gavage over a period of three months. Behavioral tests were performed in the Morris Water Maze after one, two and three months of treatment. Histological examinations were performed in the hippocampal formation and in the entorhinal cortex by measuring the synaptic density. This study shows that the oral intake of N-PEP-12 has beneficial effects on the cognitive performance of aged animals and that these effects go along with an increase in the synaptic density. Thus, N-PEP-12 may help maintain memory and learning performance during the aging process.

Safety profile of Cerebrolysin: clinical experience from dementia and stroke trials.

The safety of Cerebrolysin has been shown through many years of clinical use, observations from postmarketing surveillance studies, and safety data from randomized, controlled clinical trials. The reported events showed that adverse reactions to Cerebrolysin were generally mild and transient. Most common adverse events included vertigo, agitation and feeling hot. In the controlled clinical trials analyzed for this report, the incidence of adverse events was similar in Cerebrolysin- and placebo-treated groups. Cerebrolysin seems to be safe when used in combination with recombinant tissue-type plasminogen activator or cholinesterase inhibitors such as donepezil or rivastigmine. To our knowledge, Cerebrolysin was not associated with major changes in vital signs or laboratory parameters.

Combination treatment in Alzheimer's disease: results of a randomized, controlled trial with cerebrolysin and donepezil.

Treatment with neurotrophic agents might enhance and/or prolong the effects of cholinesterase inhibitors (ChEIs) in Alzheimer's disease (AD). We compared the safety and efficacy of the neurotrophic compound Cerebrolysin (10 ml; n=64), donepezil (10 mg; n=66) and a combination of both treatments (n=67) in mild-to-moderate (mini-mental state examination-MMSE score 12-25) probable AD patients enrolled in a randomized, double-blind trial. Primary endpoints were global outcome (Clinician's Interview-Based Impression of Change plus caregiver input; CIBIC+) and cognition (change from baseline in AD Assessment Scale-cognitive subscale+; ADAS-cog+) at week 28. Changes in functioning (AD Cooperative Study-Activities of Daily Living scale, ADCS-ADL) and behaviour (Neuropsychiatric Inventory, NPI) were secondary endpoints. Treatment effects in cognitive, functional and behavioral domains showed no significant group differences; whereas improvements in global outcome favored Cerebrolysin and the combination therapy. Cognitive performance improved in all treatment groups (mean±SD for Cerebrolysin: -1.7±7.5; donepezil: -1.2±6.1; combination: -2.3±6.0) with best scores in the combined therapy group at all study visits. Cerebrolysin was as effective as donepezil, and the combination of neurotrophic (Cerebrolysin) and cholinergic (donepezil) treatment was safe in mild-to-moderate AD. The convenience of exploring long-term synergistic effects of this combined therapy is suggested.

Efficacy and safety of Cerebrolysin in moderate to moderately severe Alzheimer's disease: results of a randomized, double-blind, controlled trial investigating three dosages of Cerebrolysin.

BACKGROUND: cerebrolysin is a neuropeptide preparation mimicking the effects of neurotrophic factors. This subgroup analysis assessed safety and efficacy of Cerebrolysin in patients with moderate to moderately severe Alzheimer's disease (AD) (ITT data set: N = 133; MMSE: 14-20) included in a dose-finding study (ITT data set: N = 51; MMSE: 14-25). Results of the mild AD subgroup (ITT data set: N = 118; MMSE: 21-25) are also presented. METHODS: patients with AD received 100 ml IV infusions of Cerebrolysin (10, 30 or 60 ml diluted in saline; N = 32, 34 and 35, respectively) or placebo (saline; N = 32) over twelve weeks (5 days per week for 4 weeks and 2 days per week for another 8 weeks). Primary efficacy criteria ADAS-cog+ (Alzheimer's Disease Assessment Scale Cognitive Subpart Modified) and CIBIC+ (Clinical Interview-based Impression of Change with Caregiver Input) were assessed 24 weeks after baseline. RESULTS: at week 24, Cerebrolysin improved the global clinical function significantly with all three dosages and induced significant improvements in cognition, initiation of activities of daily living (ADL) and neuropsychiatric symptoms at 10-, 30- and 60-ml doses, respectively. Treatment effects on total ADL and other secondary parameters (MMSE, Trail-making test) were not significant. Cerebrolysin was safe and well tolerated. CONCLUSIONS: these results demonstrate the efficacy of Cerebrolysin in moderate to moderately severe AD, showing dose-specific effects similar to those reported for patients with mild to moderate AD. The benefits of Cerebrolysin in advanced AD need to be confirmed in larger trials.

Neuroprotection of cerebrolysin in tissue culture models of brain ischemia: post lesion application indicates a wide therapeutic window.

All attempts to reduce neuronal damage after acute brain ischemia by the use of neuroprotective compounds have failed to prove efficacy in clinical trials so far. One of the main reasons might be the relatively narrow time window for intervention. In this study 2 different tissue culture models of ischemia, excitotoxic lesion by the use of glutamate and oxygen-glucose deprivation (OGD), were used to investigate the effects of delayed application of Cerebrolysin (Cere) on neuronal survival. This drug consists of low molecular weight peptides with neuroprotective and neurotrophic properties similar to naturally occurring growth factors. After both types of lesion, acute as well as delayed treatment with Cere resulted in a dose dependent and significant rescue of neurons. In the model of excitotoxic cell death significant drug effects were found even when the treatment started with a delay of 96 hours after addition of glutamate. In the OGD model pronounced effects were found after 48 hours delay of treatment, and even after 72 hours a small but significant rescue of neurons was detected. The neuroprotective effects of a single addition of Cerebrolysin to the culture medium resulted in significant protection until end of the experiments which was up to 2 weeks after the initial lesion. A shift of the efficacious dosages from low to high concentrations indicates that most likely active compounds are used up, indicating that multiple dosing might even increase the effect size. In conclusion the results indicate that Cere displays a relatively wide therapeutic time window which might be explained by a combination of acute neuroprotective properties and neurotrophic efficacy.

A peptide preparation protects cells in organotypic brain slices against cell death after glutamate intoxication.

Cerebrolysin has been shown to have neurotrophic and neuroprotective potential similar to NGF or BDNF. In the present study organotypic brain slices were utilized to determine the neuroprotective effects of Cerebrolysin, in a glutamate lesion paradigm mimicking a key event in ischemia. The study focused on the effects of Cerebrolysin on both necrotic and apoptotic cell death. Two specific DNA intercalating dyes were used to distinguish the type of cell death. The drug effect was evaluated both microscopically and quantitatively before, 24 hours after and then again 8 days after the lesion. Cerebrolysin was added either before and after the lesion or after the lesion only. The most pronounced effect was seen with the drug added both prior to and after the glutamate lesioning. A treatment after the lesion only also counteracted necrosis and apoptosis. The results render the drug relevant for treating acute as well as chronic neurodegenerative diseases.

N-PEP-12--a novel peptide compound that protects cortical neurons in culture against different age and disease associated lesions.

The neuroprotective potency of N-PEP-12, a novel, proprietary compound consisting of biopeptides and amino acids was investigated. Lesion models have been applied in neuronal cultures of embryonic chicken cortex, pre-treated with N-PEP-12 from the first day onwards. On day 8 in vitro neurons were lesioned and cell viability was measured 24 and 48 hours later. To simulate acute brain ischemia, cytotoxic hypoxia was induced by sodium cyanide or by iodoacetate and excitotoxicity by L-glutamate. Ionomycin for up to 48 hours induced calcium overload. The cytoskeleton was disrupted by addition of colchicine. N-PEP-12 shows dose-dependent neuroprotection in all different models. The effect size depends on the recovery time but also on the extent of the lesion. In cases of mild to moderate lesion pronounced dose-dependent effects could be demonstrated. This indicates that chronic exposure to N-PEP-12 is able to prevent neuronal cell death associated to conditions occurring during normal aging and neurological disorders like ischemic stroke, hypoxia, brain trauma, or AD.

Brix from xenopus laevis and brx1p from yeast define a new family of proteins involved in the biogenesis of large ribosomal subunits.

A clone was isolated from a cDNA library from early embryos of Xenopus laevis that codes for a highly charged protein containing 339 amino acids. Two putative nuclear localization signals could be identified in its sequence, but no other known motifs or domains. Closely related ORFs are present in the genomes of man, C. elegans, yeast and Arabidopsis. A fusion protein with GFP expressed in HeLa cells or Xenopus oocytes was found to be localized in the nucleolus and coiled (Cajal) bodies. Moreover, immunoprecipitation experiments demonstrated that the new Xenopus protein interacts with 5S, 5.8S and 28S RNAs of large ribosomal subunits. The name Brix (biogenesis of ribosomes in Xenopus) is proposed for this protein and the corresponding gene. In Saccharomyces cerevisiae, the essential gene YOL077c, now named BRX1, codes for the Brix homolog, which is also localized in the nucleolus. Depletion of Brx1 p in a conditional yeast mutant leads to defects in rRNA processing, and a block in the assembly of large ribosomal subunits.

Isolation of a chymotrypsinogen B-like enzyme from the archaeon Natronomonas pharaonis and other halobacteria.

A protease of a molecular mass of approximately 30kDa was isolated and purified from the haloalkaliphilic archaeon Natronomonas (formerly Natronobacterium) pharaonis. The enzyme hydrolyzed synthetic peptides, preferentially at the carboxyl terminus of phenylalanine or leucine, as well as large proteins. Hydrolysis occurred over the range of pH from 6 to 12, with an optimum at pH 10. The temperature optimum was 61 degrees C. The enzyme was nearly equally active over the range of salt concentration from 0.5 to 4M (NaCl or KCl). A strong cross-reaction with a polyclonal antiserum against human chymotrypsin was observed. Enzymatic activity was inhibited by typical serine protease inhibitors. There was significant homology between N-terminal and internal sequences from autolytic fragments and the sequence of bovine chymotrypsinogen B; the overall amino acid composition was similar to that of vertebrate chymotrypsinogens. Evidence for a zymogen-like processing of the protease was obtained. Cell extracts from other halobacteria exhibited similar proteolytic activity and immunoreactivity. The data suggested a widespread distribution of a chymotrypsinogen B-like protease among halo- and haloalkaliphilic Archaea.