Front Aging Neurosci. 2014 Dec 3;6:319. doi: 10.3389/fnagi.2014.00319. eCollection 2014.
Copper-uptake is critical for the down regulation of synapsin and dynamin induced by neocuproine: modulation of synaptic activity in hippocampal neurons.
Castro PA1, Ramirez A2, Sepúlveda FJ3, Peters C3, Fierro H3, Waldron J3, Luza S4, Fuentealba J3, Muñoz FJ5, De Ferrari GV6, Bush AI4, Aguayo LG3, Opazo CM4.
Extracellular and intracellular copper and zinc regulate synaptic activity and plasticity, which may impact brain functionality and human behavior. We have found that a metal coordinating molecule, Neocuproine, transiently increases free intracellular copper and zinc levels (i.e., min) in hippocampal neurons as monitored by Phen Green and FluoZin-3 fluorescence, respectively. The changes in free intracellular zinc induced by Neocuproine were abolished by the presence of a non-permeant copper chelator, Bathocuproine (BC), indicating that copper influx is needed for the action of Neocuproine on intracellular Zn levels. Moreover, Neocuproine decreased the mRNA levels of Synapsin and Dynamin, and did not affect the expression of Bassoon, tubulin or superoxide dismutase (SOD). Western blot analysis showed that protein levels of synapsin and dynamin were also down regulated in the presence of Neocuproine and that these changes were accompanied by a decrease in calcium transients and neuronal activity. Furthermore, Neocuproine decreased the number of active neurons, effect that was blocked by the presence of BC, indicating that copper influx is needed for the action of Neocuproine. We finally show that Neocuproine blocks the epileptiform-like activity induced by bicuculline in hippocampal neurons. Collectively, our data indicates that presynaptic protein configuration and function of primary hippocampal neurons is sensitive to transient changes in transition metal homeostasis. Therefore, small molecules able to coordinate transitio
BMC Bioinformatics. 2014 Dec 8;15 Suppl 16:S11. doi: 10.1186/1471-2105-15-S16-S11. Epub 2014 Dec 8.
Genetic algorithm with logistic regression for prediction of progression to Alzheimer's disease.
Johnson P, Vandewater L, Wilson W, Maruff P, Savage G, Graham P, Macaulay LS, Ellis KA, Szoeke C, Martins RN, Rowe CC, Masters CL, Ames D, Zhang P.
Assessment of risk and early diagnosis of Alzheimer's disease (AD) is a key to its prevention or slowing the progression of the disease. Previous research on risk factors for AD typically utilizes statistical comparison tests or stepwise selection with regression models. Outcomes of these methods tend to emphasize single risk factors rather than a combination of risk factors. However, a combination of factors, rather than any one alone, is likely to affect disease development. Genetic algorithms (GA) can be useful and efficient for searching a combination of variables for the best achievement (eg. accuracy of diagnosis), especially when the search space is large, complex or poorly understood, as in the case in prediction of AD development.
Multiple sets of neuropsychological tests were identified by GA to best predict conversions between clinical categories, with a cross validated AUC (area under the ROC curve) of 0.90 for prediction of HC conversion to MCI/AD and 0.86 for MCI conversion to AD within 36 months.
This study showed the potential of GA application in the neural science area. It demonstrated that the combination of a small set of variables is superior in performance than the use of all the single significant variables in the model for prediction of progression of disease. Variables more frequently selected by GA might be more important as part of the algorithm for prediction of disease development.
The company informs on it's web page: "The company is tracking measures of brain volume and cognition in the current 12 month extension study that will be completed at the end of the year. Further analysis of the results is ongoing."
So it is IMO not only expecting abeta to go down in the Pet scan with PBT2 ( evident after Masters's July presentation) but also it seems to expect hippocampus atrophy results and also cognition results to be stronger after 2y than after the first year. The Company has seen also the interim results during the first year while we investors have seen only one data point if that, we have no data about ApoE4 combination with BDNFmet etc.
Nobody knows what is the right dosage of PBT2. 250mg is almost only 10% what was used in the animal studies with excellet results. To compensate the low dosage, it could be that long treatment time perhaps compensates it, but nobody knows, not even the company. In any case PBT2 is not in any standstill.
cont.... This work is relevant to neurological and psychiatric disorders in which disturbed Cu homeostasis could contribute to altered synaptic transmission, including Wilson's, Menkes, Alzheimer's, and prion-related diseases.
Another mouse paper:
J Neurophysiol. 2014 May;111(10):1927-39.
In vivo and in vitro analyses of amygdalar function reveal a role for copper.
Gaier ED1, Rodriguiz RM2, Zhou J2, Ralle M3, Wetsel WC4, Eipper BA1, Mains RE5.
Mice with a single copy of the peptide amidating monooxygenase (Pam) gene (PAM(+/-)) are impaired in contextual and cued fear conditioning. These abnormalities coincide with deficient long-term potentiation (LTP) at excitatory thalamic afferent synapses onto pyramidal neurons in the lateral amygdala. Slice recordings from PAM(+/-) mice identified an increase in GABAergic tone (Gaier ED, Rodriguiz RM, Ma XM, Sivaramakrishnan S, Bousquet-Moore D, Wetsel WC, Eipper BA, Mains RE. J Neurosci 30: 13656-13669, 2010). Biochemical data indicate a tissue-specific deficit in Cu content in the amygdala; amygdalar expression of Atox-1 and Atp7a, essential for transport of Cu into the secretory pathway, is reduced in PAM(+/-) mice. When PAM(+/-) mice were fed a diet supplemented with Cu, the impairments in fear conditioning were reversed, and LTP was normalized in amygdala slice recordings. A role for endogenous Cu in amygdalar LTP was established by the inhibitory effect of a brief incubation of wild-type slices with bathocuproine disulfonate, a highly selective, cell-impermeant Cu chelator. Interestingly, bath-applied CuSO₄ had no effect on excitatory currents but reversibly potentiated the disynaptic inhibitory current. Bath-applied CuSO₄ was sufficient to potentiate wild-type amygdala afferent synapses. The ability of dietary Cu to affect signaling in pathways that govern fear-based behaviors supports an essential physiological role for Cu in amygdalar function at both the synaptic and behavioral levels. This work is relevant to neurological and psychiatric disorders in which disturbed Cu homeostasis could contribute to altered synaptic transmission, including Wilson's, Men
This paper is a rat study (cerebellum granule cells), almost 1y old, but gives understanding of Cu balance.
Brain Res. 2014 Jan 13;1542:20-31. doi: 10.1016/j.brainres.2013.10.029. Epub 2013 Oct 23.
Multiple effects of copper on NMDA receptor currents.
Marchetti C, Baranowska-Bosiacka I, Gavazzo P.
Copper (Cu) is an essential metal present in the human brain and released from synaptic vesicles following neuronal depolarization. Cu is known to reduce the NMDA receptor (NR) current with IC50≈20 µM. We have studied the effect of Cu on the NR current in cultured neonatal rat cerebellum granule cells (CGC) and in transiently transfected HEK293 cells (HEK), expressing either GluN1/GLUN2A or GluN1/GluN2B receptors. In CGCs, Cu causes a potentiation of the NR current at concentrations
Where is this info comming from ??
The daily volumes are today lower than in earlier short reports. So with this level of trading it would take some 55 days to cover. 2 wks ago this figure was 27 days.The present level of trading will take this figure even higher for the next short report.
We should have some cognition data so that we do not need to speculate. We had high Abeta levels and we had also hippocampus atrophy and so neurodegeneration for sure had started and IMO there has also been deterioration in cognition measures during the 1st year. May be that placebo cognition has deteriorated less than expected because there was also less hippocampus atrophy than expected. In 3-4 months we have more info.
There has been some speculation if the Imagine study population can ever demonstrate cognition differences because the possible deterioration is only in a very early stage.
MCI cases may develop AD, but not all of them do. But prodromal cases will develop AD. In the Imagine study there were no MCI cases but only prodromal or mild AD cases. So according that selection all Imagine cases were determined to develop AD.
According the paper below when the AD starts it will go forward. So I would say that there was some cognition deterioration after 1y but we have no info .
Alzheimers Dement. 2014 Nov;10(6):743-751.e1. doi: 10.1016/j.jalz.2013.11.005. Epub 2014 Feb 28.
Aβ and cognitive change: Examining the preclinical and prodromal stages of Alzheimer's disease.
Lim YY1, Maruff P2, Pietrzak RH3, Ellis KA4, Darby D5, Ames D6, Harrington K5, Martins RN7, Masters CL5, Szoeke C8, Savage G9, Villemagne VL10, Rowe CC11; AIBL Research Group.
High β-amyloid (Aβ) is associated with faster memory decline in healthy individuals and adults with mild cognitive impairment (MCI). However, longer prospective studies are required to determine if Aβ-related memory decline continues and whether it is associated with increased rate of disease progression.
Healthy controls (HCs; n = 177) and adults with MCI (n = 48) underwent neuroimaging for Aβ and cognitive assessment at baseline. Cognition was reassessed 18 and 36 months later.
Compared with low-Aβ HCs, high-Aβ HC and MCI groups showed moderate decline in episodic and working memory over 36 months. Those with MCI with low Aβ did not show any cognitive decline. Rates of disease progression were increased in the high-Aβ HC and MCI groups.
In healthy individuals, high Aβ likely indicates that Alzheimer's disease (AD)-related neurodegeneration has begun. Once commenced, the rate of decline in cognitive function remains constant across the preclinical and prodromal stages of AD.
I think this Lim YY et al paper was discussed here on the board when it was e-published. After that they changed the abstract slightly. I have not seen but the abstract.
To me the most important message is that cognitive decline is mediated by hippocampus atrophy because HA can be slowed down by PBT2 (trend). The question perhaps is if the power of the extension study is enough to confirm the effect of PBT2 better now during the second year and if there is any possibility to connect these measurements to cognition.
It is very difficult to compare 2 different study populations in spite there are similarities. Predicting anything by comparisons is perhaps dangerous. But I am hopeful with the early signs we had in the Imagine study, but cognition will be a big challenge because placebo is missing. FDA knows how important hippocampus is in cognition and it also knows that accumulation of Abeta will precedes AD.
Copper seems to be a difficult issue . We have it in blood, nerve endings, brain, CSF, as non-ceruloplasmin copper etc. It could be a very up-stream issue in AD as the first paper perhaps tells. I do not think the Masters's paper adds much to my understanding, it does not seem so important from the point of copper dynamics but "Our data indicate that there is a brain specific alteration in Cu levels in AD localized to the soluble extracted material, which is not reflected in erythrocytes. Further studies using metalloproteomics approaches will be able to elucidate the metabolic mechanism(s) that results in the decreased brain Cu levels during the progression of AD".
This is also important paper
Int J Alzheimers Dis. 2013;2013:623241. doi: 10.1155/2013/623241. Epub 2013 Oct 21.
Decreased copper in Alzheimer's disease brain is predominantly in the soluble extractable fraction.
Rembach A1, Hare DJ, Lind M, Fowler CJ, Cherny RA, McLean C, Bush AI, Masters CL, Roberts BR.
Alzheimer's disease (AD) is the leading cause of dementia and represents a significant burden on the global economy and society. The role of transition metals, in particular copper (Cu), in AD has become of significant interest due to the dyshomeostasis of these essential elements, which can impart profound effects on cell viability and neuronal function. We tested the hypothesis that there is a systemic perturbation in Cu compartmentalization in AD, within the brain as well as in the periphery, specifically within erythrocytes. Our results showed that the previously reported decrease in Cu within the human frontal cortex was confined to the soluble (P
I think this paper below needs to be reposted after the paper above.
J Alzheimers Dis. 2014;38(4):809-22. doi: 10.3233/JAD-131247.
Meta-analysis of serum non-ceruloplasmin copper in Alzheimer's disease.
Squitti R1, Simonelli I, Ventriglia M, Siotto M, Pasqualetti P, Rembach A, Doecke J, Bush AI.
The fraction of copper not bound to ceruloplasmin seems altered in Alzheimer's disease (AD). We have addressed this notion evaluating all the studies carried out from 1996 until March 2013 by means of meta-analysis. We performed our analysis on diverse indices evaluating the relationship between copper and ceruloplasmin in general circulation, namely 'Non-Cp copper', '% Non-Cp copper', and 'Adjusted copper'. For Non-Cp copper and % Non-Cp copper, the correct stoichiometry between copper and ceruloplasmin (6-8 atoms of copper for each ceruloplasmin molecule) in healthy controls has been adopted as criterion for the study to be included in the meta-analysis evaluating data with the canonic Walshe's formula for Non-Cp copper. Copper to ceruloplasmin ratio (Cu:Cp), which is an internal quality control check for ceruloplasmin calibration, was used as an index of the actual stoichiometry in the specimens. Adjusted (Adj-Cp) copper, even though less reliable, was calculated, allowing the evaluation of all the studies selected. An additional meta-analysis of systemic total copper was re-calculated accounting for all the studies carried out from 1983 to March 2013. Ten studies were analyzed in the meta-analysis for Non-Cp copper and % Non-Cp copper reaching a pooled total of 599 AD subjects and 867 controls. For Adj-Cp copper, 14 studies were analyzed with a pooled total of 879 AD and 1,712 controls. 27 studies were considered for systemic total copper meta-analysis, with a pooled total of 1,393 AD and 2,159 controls. All the copper indices analyzed were significantly higher in AD subjects compared to healthy controls.
Biochem J. 2014 Dec 4. [Epub ahead of print]
Cu2+ accentuates distinct misfolding for Aβ(1-40) and Aβ(1-42) peptides, and potentiates membrane disruption.
Matheou CJ, Younan ND, Viles JH.
Central to Alzheimer's Disease is the misfolding of amyloid-beta (Aβ) peptide, which generates an assorted population of amorphous aggregates, oligomers and fibres. Metal ion homeostasis is disrupted in the brains of sufferers of Alzheimer's disease and causes heightened Alzheimer's disease phenotype in animal models. Here we illustrate that substochiometric Cu2+ effects the misfolding pathway of Aβ(1-40), and the more toxic Aβ(1-42), in markedly different ways. Cu2+ accelerates Aβ(1-40) fibre formation, in contrast, for Aβ(1-42) substoichiometric levels of Cu2+ almost exclusively promotes the formation of oligomeric and protofibrillar assemblies. Indeed, mature Aβ(1-42) fibres are disassembled into oligomers when Cu2+ is added. These Cu2+ stabilised oligomers of Aβ(1-42) interact with the lipid-bilayer, disrupting the membrane and increasing permeability. Our investigation of Aβ(1-40)/Aβ(1-42) mixtures with Cu2+ revealed that Aβ(1-40) neither contributed nor perturbed formation of Aβ(1-42) oligomers, though Cu2+-Aβ(1-42) will frustrate Cu2+-Aβ(1-40) fibre growth. Small amounts of Cu2+ accentuates differences in the propensity of Aβ(1-40) and Aβ(1-42) to form synaptotoxic oligomers, providing an explanation for the connection between disrupted Cu2+ homeostasis and elevated Aβ(1-42) neurotoxicity in Alzheimer's disease.
Those who sold to balance their taxes buy now back. They trust on Prana but they are realistic and do not want to pay taxes if it is possible.
The last time shorts went up was 08/15/ 2014 (settlement date) and since that downwards. It was 3.779M but now "only" 3.420M. Still high !