Mysterious Mechanisms of Memory Formation: Are the Answers Hidden in Synapses?

Neurological manifestations of encephalitic alphaviruses, traumatic brain injuries, and organophosphorus nerve agent exposure

Encephalitic alphaviruses (EEVs), Traumatic Brain Injuries (TBI), and organophosphorus nerve agents (NAs) are three diverse biological, physical, and chemical injuries that can lead to long-term neurological deficits in humans. EEVs include Venezuelan, eastern, and western equine encephalitis viruses. This review describes the current understanding of neurological pathology during these three conditions, provides a comparative review of case studies vs. animal models, and summarizes current therapeutics. While epidemiological data on clinical and pathological manifestations of these conditions are known in humans, much of our current mechanistic understanding relies upon animal models. Here we review the animal models findings for EEVs, TBIs, and NAs and compare these with what is known from human case studies. Additionally, research on NAs and EEVs is limited due to their classification as high-risk pathogens (BSL-3) and/or select agents; therefore, we leverage commonalities with TBI to develop a further understanding of the mechanisms of neurological damage. Furthermore, we discuss overlapping neurological damage mechanisms between TBI, NAs, and EEVs that highlight novel medical countermeasure opportunities. We describe current treatment methods for reducing neurological damage induced by individual conditions and general neuroprotective treatment options. Finally, we discuss perspectives on the future of neuroprotective drug development against long-term neurological sequelae of EEVs, TBIs, and NAs.

Messenger RNA transcription levels of neuronal soluble N-ethylmaleimide-sensitive factor attachment protein receptor complex components in the olfactory nerve system of the anadromous Pacific salmon, masu salmon Oncorhynchus masou

Anadromous Pacific salmon (genus Oncorhynchus) are known for homing behavior to their natal rivers based on olfactory imprinted memories during seaward migration. The SNARE complex is a regulator of vesicle exocytosis from the presynaptic membrane. Our previous study suggested that its component genes (Snap25, Stx1, and Vamp2) are more highly expressed in the olfactory nervous system (ONS) during the migration stages associated with olfactory imprinting in the evolutionary species of Pacific salmon, such as chum (O. keta) and pink (O. gorbuscha) salmon. Masu salmon (O. masou) has a significantly different life history from these species, living longer in rivers and being a more primitive Pacific salmon species. In this study, the transcription of snare mRNAs in the ONS was analyzed using mainly male wild masu salmon. Five cDNAs encoding masu salmon SNAREs, which are well conserved among vertebrates, were isolated and sequenced. Each snare mRNA was highly expressed in age 1+ (yearling) parr prior to smoltification, particularly in the olfactory bulb. Their transcription status was significantly different from that of chum and pink salmon, which showed high expression in earlier under-yearling juveniles. The present results and our previous studies indicate that snare mRNAs are highly transcripted until the seaward migration, reflecting neural development and neuroplasticity of the ONS for olfactory imprinting.

The Role of Acetylation and Methylation of Rat Hippocampal Histone H3 in the Mechanism of Aluminum-Induced Neurotoxicity

Aluminum is a known neurotoxin and a major environmental contributor to neurodegenerative diseases such as Alzheimer's disease (AD). We uesd a subchronic aluminum chloride exposure model in offspring rats by continuously treating them with AlCl3 solution from the date of birth until day 90 in this research. Then evaluated the neurobehavioral changes in rats, observed the ultrastructural changes of hippocampal synapses and neurons, and examined the level of hippocampal acetylated histone H3 (H3ac), the activity and protein expression of hippocampal HAT1 and G9a, and the protein expression level of H3K9 dimethylation (H3K9me2). The findings demonstrated that aluminum-treated offspring rats had impaired learning and memory abilities as well as ultrastructural alterations in hippocampal synapses and neurons. The level of histone H3ac was decreased along with decreased protein expression and activity of HAT1, while level of H3K9me2 was increased along with increased protein expression and activity of G9a.

Cognition and Pain: A Review

Cognition is defined as the brain's ability to acquire, process, store, and retrieve information. Pain has been described as an unpleasant sensory or emotional experience, and for experiencing pain consciously, cognitive processing becomes imperative. Moreover, evaluation of pain strongly depends on cognition as it requires learning and recall of previous experiences. There could be a possible close link between neural systems involved in cognition and pain processing, and studies have reported an association between pain and cognitive impairment. In this narrative review, we explore the available evidence that has investigated cognitive changes associated with pain. We also examine the anatomical, biochemical, and molecular association of pain and neuro-cognition. Additionally, we focus on the cognitive impairment caused by analgesic medications. There is a need to improve our understanding of pathophysiology and cognitive impairment mechanisms associated with chronic pain and its treatment. This area provides a diverse opportunity for grounding future research, aiding institution of timely interventions to prevent chronic pain and associated cognitive decline, ultimately improving patient care.

In vitro comparison of major memory-support dietary supplements for their effectiveness in reduction/inhibition of beta-amyloid protein fibrils and tau protein tangles: key primary targets for memory loss

Memory loss is primarily caused by the accumulation of both brain plaques [(consisting of beta-amyloid protein (Aβ) 1–42)] and neurofibrillary tangles (consisting of paired helical and straight filaments containing tau protein). Neuroinflammation is the third key and important factor that leads to accelerated memory loss and eventual dementia. Brain plaques, tangles and inflammation is the trilogy mainly responsible for causing memory loss that has now been documented for over 20 years in the scientific literature. The present investigation used in vitro quantitative methods to directly compare the ability of major memory-support dietary supplements to reduce pre-formed Aβ 1–42 fibrils (21 supplements tested) and tau protein paired helical/straight filaments (13 supplements tested)—two of the three most important targets for memory loss. Additionally, 18 different manufacturers of cat’s claw (Uncaria tomentosa) were directly compared for their ability to inhibit/reduce Aβ 1–42 fibrils and/or tau paired helical/straight filaments based on recent findings that PTI-00703 cat’s claw is a specific and potent inhibitor/reducer of all three targets -brain plaques, tangles and inflammation (Snow et al. in Sci Rep 9:561, 2019). In the present investigation quantitative Thioflavin T fluorometry was used on a comparative weight-to-weight basis at increasing concentrations with ingredients tested from the actual capsules the consumer ingests. Major memory-support dietary supplements were directly compared for their ability to inhibit and disaggregate/reduce both Aβ 1–42 fibrils and/or tau paired helical/straight filaments. Dietary supplements touted to enhance memory comparatively tested included Prevagen, FOCUSfactor, PROCERA AVH, Alpha Brain, NAD⁺OVIM, BRAIN JUICE, Cebria, EXCELEROL, NOOCUBE, US Doctor’s Clinical Brain Power ADVANCED, healthycell pro, LUMONOL, Brain Awake, BRAIN ARMOR, brainMD (BRAIN & MEMORY POWER BOOST), Brain Support, Clarity (BRAIN HEALTH FORMULA), brainMD (NEUROVITE PLUS), neuriva (Original and Plus) and percepta. This is the first paper to actually comparatively test these memory-support supplements for their ability to reduce Aβ fibrils and tau protein tangles. Percepta (PTI-00703 cat’s claw and a specific oolong tea extract) was determined to be the most effective and potent memory support dietary supplement to disaggregate/disrupt Aβ 1–42 fibrils (range of 25–89%) and tau paired helical/straight filaments (range of 26–86%) at all 3–4 doses tested in comparison to other major memory-support dietary supplements tested. This was at least more than double (> 50%) for percepta reducing Aβ 1–42 fibrils and in comparison to the other 20 memory-support dietary supplements tested. The ranking order for memory-support supplement effects based on reducing Aβ 1–42 fibrils (Aβ 1–42: memory-support supplement at 1:0.1 weight-to-weight in a 3-day study) was percepta (69.6% reduction) >>> Alpha Brain (34.9% reduction) = US Doctor’s Clinical Brain Power ADVANCED (32.4%) = BRAIN JUICE (30.1%) = neuriva Plus (27%) = neuriva Original (27%) > NEUROVITE PLUS (22.9%) = NOOCUBE (19.9%) = EXCELEROL (17.3%) = healthycell pro (17.2%) > Prevagen (12.9%) > PROCERA AVH (6.5%) = FOCUSfactor (5.5%) > Cebria (0%) = Brain Awake (0%) = Brain Support (0%) = brainMD (BRAIN & MEMORY POWER BOOST) (0%) = NAD⁺OVIM (0%) = BRAIN ARMOR (0%) = LUMONOL (0%). The ranking order for memory support supplement effects on reducing tau paired helical/straight filaments (tau:memory supplement at 1:1 weight-to-weight at 3 days) was percepta (85.7% reduction) >>> neuriva Plus (57.9%) >> BRAIN JUICE (41.9%) = EXCELEROL (41.0%) = neuriva Original (38.4%) = US Doctor’s Clinical Brain Power ADVANCED (38.3%) = healthycell pro (37.6%) >> Alpha Brain (27.9%) >> NOOCUBE (17.6%) >> FOCUSfactor (8.7%) > Cebria (3.6%) = PROCERA AVH (0%) = Prevagen (0%). Congo red staining, Thioflavin S fluorescence, circular dichroism (CD) spectroscopy and electron microscopy confirmed the positive results observed with the supplement percepta. CD spectroscopy demonstrated that percepta caused a marked inhibition of beta-sheet secondary folding of tau protein into paired helical filaments. PTI-00703 cat’s claw (main ingredient in percepta) was also identified as the most potent cat’s claw bark powder (Uncaria tomentosa) to reduce and inhibit Aβ 1–42 fibrils and tau tangles in comparison to 17 other manufacturers of cat’s claw extracts. Although there are thousands of brain memory-support dietary supplements in the marketplace today, none of them have been directly compared and analyzed for their ability to reduce and/or inhibit two major targets of memory loss i.e. Aβ 1–42 fibrils and tau paired helical/straight filaments (major constituents of brain plaques and tangles). In our comparison studies, we show that percepta has the most potent ability to disaggregate/reduce Aβ 1–42 fibrils and tau protein paired helical/straight filaments as demonstrated by a variety of methods most likely due to the specific polyphenol content in PTI-00703 cat’s claw (i.e. polyphenols and proanthocyanidins) as we have previously shown (Snow et al. in Sci Rep 9:561, 2019). Memory-support dietary supplements tested that also contained polyphenols and/or cat’s claw in their product demonstrated some Aβ fibril and tau protein tangle reducing activity, but were much less effective than percepta. Percepta’s main ingredient, PTI-00703 cat’s claw, has previously been shown to reduce brain amyloid plaques and Aβ 1–42/40 insoluble/soluble levels in brain (in plaque-producing transgenic mice) with marked concurrent memory improvements (shown by Morris water maze testing) (Snow et al. in Sci Rep 9:561, 2019). The present investigation further confirms that percepta is one of the best dietary supplements that causes a marked reduction and inhibition of Aβ fibrils and tau tangle filaments -two important major targets for memory-support. In addition, PTI-00703 cat’s claw was the most effective cat’s claw (Uncaria tomentosa) ingredient for reducing /disaggregating and inhibiting Aβ 1–42 fibrils and tau protein paired helical/straight filaments in comparison to 17 other manufacturers of cat’s claw extracts tested.

Place and Environment in the Ongoing Evolution of Cognitive Neuroscience

Cognitive science today increasingly is coming under the influence of embodied, embedded, extended, and enactive perspectives, superimposed on the more traditional cybernetic, computational assumptions of classical cognitive research. Neuroscience has contributed to a greatly enhanced understanding of brain function within the constraints of the traditional cognitive science approach, but interpretations of many of its findings can be enriched by the newer alternative perspectives. Here, we note in particular how these frameworks highlight the cognitive requirements of an animal situated within its particular environment, how the coevolution of an organism's biology and ecology shape its cognitive characteristics, and how the cognitive realm extends beyond the brain of the perceiving animal. We argue that these insights of the embodied cognition paradigm reveal the central role that "place" plays in the cognitive landscape and that cognitive scientists and philosophers alike can gain from paying heed to the importance of a concept of place. We conclude with a discussion of how this concept can be applied with respect to cognitive function, species comparisons, ecologically relevant experimental designs, and how the "hard problem" of consciousness might be approached, among its other implications.

Risk of Alcohol Abuse in Humans with Attention-deficit/Hyperactivity Disorder Symptoms

The relationship between attention-deficit/hyperactivity disorder (ADHD) and the risk of alcohol abuse is widely studied. Even though this topic has been of interest for several years, it is heavily debated. We studied various papers and conducted a systematic review using PubMed as the main source of data collection. We found that several studies put forward the concept of a positive association between alcohol abuse and ADHD symptoms, but a minority of them also showed opposing and contradictory results. We discovered that this inconsistency observed in studies could be a result of a biased approach in studies and a subjective attempt in interpretations. These biases could be studied in terms of sample size involved in the analysis, age at which studies are conducted among other statistical parameters. We believe that the deviations in the outcomes prove that the studies may be incomplete and that a standardized method of interpretation is required. Therefore, this paper recommends the need for further research to explore the connection between alcohol abuse in patients showing ADHD symptoms.