Sialic Acid and Sialylated Oligosaccharide Supplementation during Lactation Improves Learning and Memory in Rats

Sialic acids (Sia) are postulated to improve cognitive abilities. This study evaluated Sia effects on rat behavior when administered in a free form as N-acetylneuraminic acid (Neu5Ac) or conjugated as 6′-sialyllactose (6′-SL). Rat milk contains Sia, which peaks at Postnatal Day 9 and drops to a minimum by Day 15. To bypass this Sia peak, a cohort of foster mothers was used to raise the experimental pups. A group of pups received a daily oral supplementation of Neu5Ac to mimic the amount naturally present in rat milk, and another group received the same molar amount of Sia as 6′-SL. The control group received water. After weaning, rats were submitted to behavioral evaluation. One year later, behavior was re-evaluated, and in vivo long-term potentiation (LTP) was performed. Brain samples were collected and analyzed at both ages. Adult rats who received Sia performed significantly better in the behavioral assessment and showed an enhanced LTP compared to controls. Within Sia groups, 6′-SL rats showed better scores in some cognitive outcomes compared to Neu5Ac rats. At weaning, an effect on polysialylated-neural cell adhesion molecule (PSA-NCAM) levels in the frontal cortex was only observed in 6′-SL fed rats. Providing Sia during lactation, especially as 6′-SL, improves memory and LTP in adult rats.

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How does intraarticular dexmedetomidine injection effect articular cartilage and synovium? An animal study

BMC Anesthesiology ◽

10.1186/s12871-020-01148-x ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Başak Akça ◽

Aysun Ankay Yılbaş ◽

Filiz Üzümcügil ◽

Berkem Büyükakkuş ◽

Elham Bahador Zırh ◽

...

Keyword(s):

Pain Relief ◽

Knee Joint ◽

Animal Study ◽

Left Knee ◽

Control Group ◽

Sprague Dawley ◽

Adult Rats ◽

Arthroscopic Knee ◽

The Right

Abstract Background Intraarticular injections are widely used to provide pain relief after arthroscopic procedures and minimize the use of opioids. Dexmedetomidine has been proven to potentiate pain relief and postpone the demand for the first analgesic drug when it is used intraarticularly following arthroscopic knee procedures. However, the effects of dexmedetomidine on articular structures have not yet been evaluated. Our aim was to determine the effects of intraarticular dexmedetomidine injection on articular structures such as cartilage and synovium. Design Animal study. Methods Twenty adult rats (Sprague-Dawley) were enrolled in the study. Following appropriate aseptic and anesthetic conditions, dexmedetomidine (100 mcg/ml) (0.25 ml) was injected into the right knee joint (the study group) and normal saline solution (0.25 ml) into the left knee joint (the control group) of the rats. Four rats were sacrificed from each group on days 1, 2, 7, 14, and 21, and knee joint samples were obtained. Histologists evaluated the articular and periarticular regions and the synovium using histological sections, and a five-point scale was used to grade the inflammatory changes in a blinded manner. Results The groups were found to be similar in terms of median congestion scores, edema and inflammation scores, subintimal fibrosis, neutrophil activation and cartilage structure at each of the time intervals. Conclusion In our placebo-controlled, in vivo trial, the intraarticular use of dexmedetomidine seemed to be safe with respect to the studied histopathological parameters. However, complementary studies investigating the histopathological effects, analgesic dosage and adverse effects of dexmedetomidine on damaged articular structure models are needed.

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Lactose malabsorption and colonic fermentations alter host metabolism in rats

British Journal Of Nutrition ◽

10.1017/s0007114512005557 ◽

2013 ◽

Vol 110 (4) ◽

pp. 625-631 ◽

Cited By ~ 12

Author(s):

Virginie Alexandre ◽

Patrick C. Even ◽

Christiane Larue-Achagiotis ◽

Jean-Marc Blouin ◽

François Blachier ◽

...

Keyword(s):

Colonic Mucosa ◽

Portal Blood ◽

Control Group ◽

Adult Rats ◽

Lactose Malabsorption ◽

Host Interactions ◽

Enhanced Production ◽

Host Metabolism ◽

Experimental Group

Lactose malabsorption is associated with rapid production of high levels of osmotic compounds, such as organic acids and SCFA in the colon, suspected to contribute to the onset of lactose intolerance. Adult rats are lactase deficient and the present study was conducted to evaluatein vivothe metabolic consequences of acute lactose ingestion, including host–microbiota interactions. Rats received diets of 25 % sucrose (S25 control group) or 25 % lactose (L25 experimental group). SCFA and lactic acid were quantified in intestinal contents and portal blood. Expression of SCFA transporter genes was quantified in the colonic mucosa. Carbohydrate oxidation (Cox) and lipid oxidation (Lox) were computed by indirect calorimetry. Measurements were performed over a maximum of 13 h. Time, diet and time × diet variables had significant effects on SCFA concentration in the caecum (P< 0·001,P= 0·004 andP= 0·007, respectively) and the portal blood (P< 0·001,P= 0·04 andP< 0·001, respectively). Concomitantly, expression of sodium monocarboxylate significantly increased in the colonic mucosa of the L25 group (P= 0·003 att= 6 h andP< 0·05 att= 8 h). During 5 h after the meal, the L25 group's changes in metabolic parameters (Cox, Lox) were significantly lower than those of the S25 group (P= 0·02). However, after 5 h, L25 Cox became greater than S25 (P= 0·004). Thus, enhanced production and absorption of SCFA support the metabolic changes observed in calorimetry. These results underline the consequences of acute lactose malabsorption and measured compensations occurring in the host's metabolism, presumably through the microbiota fermentations and microbiota–host interactions.

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Neurobehavioral and Ultrastructural Changes Induced by Phytosynthesized Silver-Nanoparticle Toxicity in an In Vivo Rat Model

Nanomaterials ◽

10.3390/nano12010058 ◽

2021 ◽

Vol 12 (1) ◽

pp. 58

Author(s):

Razvan Vlad Opris ◽

Vlad Toma ◽

Alina Mihaela Baciu ◽

Remus Moldovan ◽

Bogdan Dume ◽

...

Keyword(s):

Brain Regions ◽

Time Dependent ◽

Ultrastructural Changes ◽

Control Group ◽

Adult Rats ◽

Male Adult ◽

Cornus Mas ◽

Transmission Electron ◽

Altered Cell

(1) Background: The study aimed to assess neurobehavioral, ultrastructural, and biochemical changes induced by silver nanoparticles synthesized with Cornus mas L. extract (AgNPs-CM) in rat brains. (2) Methods: The study included 36 male adult rats divided into three groups. Over a period of 45 days, AgNPs-CM (0.8 and 1.5 mg/kg b.w.) were administered daily by gavage to two of the groups, while the control group received the vehicle used for AgNP. After treatment, OFT and EPM tests were conducted in order to assess neurobehavioral changes. Six of the animals from each group were sacrificed immediately after completion of treatment, while the remaining six were allowed to recuperate for an additional 15 days. Transmission electron microscopy (TEM), GFAP immunohistochemistry, and evaluation of TNFα, IL-6, MDA, and CAT activity were performed on the frontal cortex and hippocampus. (3) Results: Treated animals displayed a dose- and time-dependent increase in anxiety-like behavior and severe ultrastructural changes in neurons, astrocytes, and capillaries in both brain regions. Immunohistochemistry displayed astrogliosis with altered cell morphology. TNFα, IL-6, MDA, and CAT activity were significantly altered, depending on brain region and time post exposure. (4) Conclusions: AgNPs-CM induced neurobehavioral changes and severe cell lesions that continued to escalate after cessation of exposure.

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Effects of perfluorooctane sulfonate and its alternatives on long-term potentiation in the hippocampus CA1 region of adult rats in vivo

Toxicology Research ◽

10.1039/c5tx00184f ◽

2016 ◽

Vol 5 (2) ◽

pp. 539-546 ◽

Cited By ~ 18

Author(s):

Qian Zhang ◽

Wei Liu ◽

Qiao Niu ◽

Yu Wang ◽

Huimin Zhao ◽

...

Keyword(s):

Health Effects ◽

Perfluorooctane Sulfonate ◽

Long Term Potentiation ◽

Adult Rats ◽

Ca1 Region ◽

Term Potentiation

With the limited but ongoing usage of perfluorooctane sulfonate (PFOS), the health effects of both PFOS and its alternatives are far from being understood.

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In Vivo Roles for Matrix Metalloproteinase-9 in Mature Hippocampal Synaptic Physiology and Plasticity

Journal of Neurophysiology ◽

10.1152/jn.00202.2007 ◽

2007 ◽

Vol 98 (1) ◽

pp. 334-344 ◽

Cited By ~ 102

Author(s):

Ozlem Bozdagi ◽

Vanja Nagy ◽

Kimberly T. Kwei ◽

George W. Huntley

Keyword(s):

Synaptic Plasticity ◽

Proteolytic Activity ◽

Neutralizing Antibodies ◽

Long Term Potentiation ◽

Receptor Activation ◽

Synaptic Function ◽

Loss Of Function ◽

Adult Rats ◽

Area Ca1

Extracellular proteolysis is an important regulatory nexus for coordinating synaptic functional and structural plasticity, but the identity of such proteases is incompletely understood. Matrix metalloproteinases (MMPs) have well-known, mostly deleterious roles in remodeling after injury or stroke, but their role in nonpathological synaptic plasticity and function in intact adult brains has not been extensively investigated. Here we address the role of MMP-9 in hippocampal synaptic plasticity using both gain- and loss-of-function approaches in urethane-anesthetized adult rats. Acute blockade of MMP-9 proteolytic activity with inhibitors or neutralizing antibodies impairs maintenance, but not induction, of long-term potentiation (LTP) at synapses formed between Schaffer-collaterals and area CA1 dendrites. LTP is associated with significant increases in levels of MMP-9 and proteolytic activity within the potentiated neuropil. By introducing a novel application of gelatin-substrate zymography in vivo, we find that LTP is associated with significantly elevated numbers of gelatinolytic puncta in the potentiated neuropil that codistribute with immunolabeling for MMP-9 and for markers of synapses and dendrites. Such increases in proteolytic activity require NMDA receptor activation. Exposing intact area CA1 neurons to recombinant-active MMP-9 induces a slow synaptic potentiation that mutually occludes, and is occluded by, tetanically evoked potentiation. Taken together, our data reveal novel roles for MMP-mediated proteolysis in regulating nonpathological synaptic function and plasticity in mature hippocampus.

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Intracerebroventricular injection of oxidant and antioxidant molecules affects long-term potentiation in urethane anaesthetized rats

Physiological Research ◽

10.33549/physiolres.930973 ◽

2008 ◽

pp. 269-273

Author(s):

A Viggiano ◽

E Viggiano ◽

M Monda ◽

A Viggiano ◽

S Ascione ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Dentate Gyrus ◽

Long Term Potentiation ◽

Control Group ◽

High Frequency Stimulation ◽

Perforant Pathway ◽

Term Potentiation ◽

Stimulation Of

Production of superoxide anions in the incubation medium of hippocampal slices can induce long-term potentiation (LTP). Other reactive oxygen species (ROS) such as hydrogen peroxide are able to modulate LTP and are likely to be involved in aging mechanisms. The present study explored whether intracerebroventricular (ICV) injection of oxidant or antioxidant molecules could affect LTP in vivo. With this aim in mind, field excitatory post-synaptic potentials (fEPSPs) elicited by stimulation of the perforant pathway were recorded in the dentate gyrus of the hippocampal formation in urethane-anesthetized rats. N-acetyl-Lcysteine, hydrogen peroxide (H2O2) or hypoxanthine/xanthineoxidase solution (a superoxide producing system) were administrated by ICV injection. The control was represented by a group injected with saline ICV. Ten minutes after the injection, LTP was induced in the granule cells of the dentate gyrus by high frequency stimulation of the perforant pathway. Neither the H2O2 injection or the N-acetyl-L-cysteine injection caused any variation in the fEPSP at the 10-min post-injection time point, whereas the superoxide generating system caused a significant increase in the fEPSP. Moreover, at 60 min after tetanic stimulation, all treatments attenuated LTP compared with the control group. These results show that ICV administration of oxidant or antioxidant molecules can modulate LTP in vivo in the dentate gyrus. Particularly, a superoxide producing system can induce potentiation of the synaptic response. Interestingly, ICV injection of oxidants or antioxidants prevented a full expression of LTP compared to the saline injection.

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Sex differences in the behavioral and synaptic consequences of a single exposure to cannabinoid at puberty and adulthood

10.1101/415067 ◽

2018 ◽

Author(s):

Milene Borsoi ◽

Antonia Manduca ◽

Anissa Bara ◽

Olivier Lassalle ◽

Anne-Laure Pelissier-Alicot ◽

...

Keyword(s):

Sex Differences ◽

Social Behavior ◽

Pyramidal Neurons ◽

Long Term Potentiation ◽

Adult Males ◽

Adult Rats ◽

Term Potentiation ◽

Cannabis Consumption

AbstractHeavy cannabis consumption among adolescents is associated with significant and lasting neurobiological, psychological and health consequences that depend on the age of first use. Chronic exposure to cannabinoid (CB) agonists during adolescence alters social behavior and prefrontal cortex (PFC) activity in adult rats. However, sex differences on social behavior as well as PFC synaptic plasticity after acute CB activation remain poorly explored. Here, we determined the consequences of a single CB activation differently affects PFC in males and females by assessing social behavior and PFC neuronal and synaptic functions in rats during pubertal or adulthood periods, 24h after a single in-vivo cannabinoid exposure (SCE). During puberty, SCE reduced play behavior in females but not males. In contrast, SCE impaired sociability in both sexes at adulthood. General exploration and memory recognition remained normal at both ages and both sexes. At the synaptic level, SCE ablated endocannabinoid-mediated long-term depression (eCB-LTD) in the PFC of females of both ages and heightened excitability of PFC pyramidal neurons at adulthood, while males were spared. In contrast, SCE was associated to impaired long-term potentiation in adult males. Together, the data indicate behavioral and synaptic sex differences in response to a single in-vivo exposure to cannabinoid at puberty and adulthood.

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Associative spike timing-dependent potentiation of the basal dendritic excitatory synapses in the hippocampus in vivo

Journal of Neurophysiology ◽

10.1152/jn.00188.2016 ◽

2016 ◽

Vol 115 (6) ◽

pp. 3264-3274 ◽

Cited By ~ 6

Author(s):

Thomas K. Fung ◽

Clayton S. Law ◽

L. Stan Leung

Keyword(s):

Current Source ◽

Long Term Potentiation ◽

Spike Timing ◽

Stratum Radiatum ◽

Adult Rats ◽

Synaptic Excitation ◽

Stratum Oriens ◽

Term Potentiation

Spike timing-dependent plasticity in the hippocampus has rarely been studied in vivo. Using extracellular potential and current source density analysis in urethane-anesthetized adult rats, we studied synaptic plasticity at the basal dendritic excitatory synapse in CA1 after excitation-spike (ES) pairing; E was a weak basal dendritic excitation evoked by stratum oriens stimulation, and S was a population spike evoked by stratum radiatum apical dendritic excitation. We hypothesize that positive ES pairing—generating synaptic excitation before a spike—results in long-term potentiation (LTP) while negative ES pairing results in long-term depression (LTD). Pairing (50 pairs at 5 Hz) at ES intervals of −10 to 0 ms resulted in significant input-specific LTP of the basal dendritic excitatory sink, lasting 60–120 min. Pairing at +10- to +20-ms ES intervals, or unpaired 5-Hz stimulation, did not induce significant basal dendritic or apical dendritic LTP or LTD. No basal dendritic LTD was found after stimulation of stratum oriens with 200 pairs of high-intensity pulses at 25-ms interval. Pairing-induced LTP was abolished by pretreatment with an N-methyl-d-aspartate receptor antagonist, 3-(2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP), which also reduced spike bursting during 5-Hz pairing. Pairing at 0.5 Hz did not induce spike bursts or basal dendritic LTP. In conclusion, ES pairing at 5 Hz resulted in input-specific basal dendritic LTP at ES intervals of −10 ms to 0 ms but no LTD at ES intervals of −20 to +20 ms. Associative LTP likely occurred because of theta-rhythmic coincidence of subthreshold excitation with a backpropagated spike burst, which are conditions that can occur naturally in the hippocampus.

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Abundant GFP Expression and LTP in Hippocampal Acute Slices by In Vivo Injection of Sindbis Virus

Journal of Neurophysiology ◽

10.1152/jn.2001.86.2.1037 ◽

2001 ◽

Vol 86 (2) ◽

pp. 1037-1042 ◽

Cited By ~ 15

Author(s):

Massimo D'Apuzzo ◽

Georgia Mandolesi ◽

Gerald Reis ◽

Erin M. Schuman

Keyword(s):

Hippocampal Neurons ◽

Sindbis Virus ◽

Fluorescent Protein ◽

Hippocampal Slices ◽

Pyramidal Cells ◽

Long Term Potentiation ◽

Neuronal Structure ◽

Adult Rats ◽

Acute Hippocampal Slices

Virus-mediated gene transfer into neurons is a powerful tool for the analysis of neuronal structure and function. Recombinant sindbis virus has been previously used to study protein function in hippocampal neuron cultures as well as in hippocampal organotypic slice cultures. Nevertheless, some concern still exists about the physiological relevance of these cultured preparations. Acute hippocampal slices are a widely used preparation for the study of synaptic transmission, but currently recombinant gene delivery is usually achieved only through time-consuming transgenic techniques. In this study, we show that a subregion of the CA1 area in acute hippocampal slices can be specifically altered to express a gene of interest. A sindbis virus vector carrying an enhanced green fluorescent protein (EGFP) reporter was injected in vivo into the hippocampus of adult rats. After 18 h, rats were killed, and acute hippocampal slices, infected in the CA1 field, were analyzed morphologically and electrophysiologically. Infected slices showed healthy and stable electrophysiological responses as well as long-term potentiation. In addition, infected pyramidal cells were readily recognized in living slices by two-photon imaging. Specifically, the introduction of an EGFP-Actin fusion protein greatly enhanced the detection of fine processes and dendritic spines. We propose this technique as an efficient tool for studying gene function in adult hippocampal neurons.

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Analysis of the Kinesiology of Skate Skiing and Roller Skiing

Baltic Journal of Sport and Health Sciences ◽

10.33607/bjshs.v3i70.492 ◽

2018 ◽

Vol 3 (70) ◽

Author(s):

Jiří Suchý ◽

Bronislav Kračmar

Keyword(s):

Frontal Plane ◽

Gluteus Medius ◽

Shoulder Girdle ◽

Lower Limbs ◽

Bipedal Walking ◽

Free Form ◽

Control Group ◽

Step Cycle ◽

Cross Country

The peak of human locomotive ontogenesis is unsupported bipedal walking. We can assume that the patterns for locomotion in sport correspond to the patterns for walking. In this study the coordination of motion in six selected key muscle groups and one control group was observed during the use of cross-country skis with ski-poles on snow (free form, skating), and compared with the coordination using roller skis with poles on asphalt. The comparison was carried out skating up a slight slope. Intraindividual analysis of these forms of locomotion was based on surface electromyography (EMG) synchronized with digital video recorded in vivo on site. The data acquired were evaluated by calculating the area under the EMG curve recorded for each muscle under observation. The probability values acquired in this way roughly show the activation and work of the monitored muscle. An ordering of local maximums within a given step cycle was established in order to judge the coordination of motion. The measured data confirmed the phenomenon of triple extension in the lower limbs as well as the phenomenon of pelvic stabilisation in the frontal plane in the single-support position. This stabilisation is ensured by the musculus gluteus medius, which was the only muscle measured to show a different ordering of local EMG curve maximums (timing) when comparing the whole cycle of skiing locomotion on asphalt and on snow. The peaks of activity for this muscle were localised outside the activity peaks of the musculus latissimus dorsi, which is considered the deciding muscle for locomotion realised through the shoulder girdle, but which also performs a stabilising function. Thus both muscles alternate in ensuring stability. The results of the pilot study described demonstrate sufficient kinesiological correspondence between locomotion on skis and on roller skis with poles to confirm the suitability of regular use of roller skis as a specific training instrument for skiing.Keywords: human locomotion, electromyography, skating on cross-country skis and on roller skis.

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