Olfactory training with Aromastics: olfactory and cognitive effects

Abstract Purpose The olfactory system can be successfully rehabilitated with regular, intermittent stimulation during multiple daily exposures to selected sets of odors, i.e., olfactory training (OT). OT has been repeatedly shown to be an effective tool of olfactory performance enhancement. Recent advancements in studies on OT suggest that its beneficial effects exceed olfaction and extend to specific cognitive tasks. So far, studies on OT provided compelling evidence for its effectiveness, but there is still a need to search for an optimal OT protocol. The present study examined whether increased frequency of OT leads to better outcomes in both olfactory and cognitive domains. Method Fifty-five subjects (28 females; Mage = 58.2 ± 11.3 years; 26 patients with impaired olfaction) were randomly assigned to a standard (twice a day) or intense (four times a day) OT. Olfactory and cognitive measurements were taken before and after OT. Results OT performed twice a day was more effective in supporting olfactory rehabilitation and interventions targeted to verbal semantic fluency than OT performed four times a day, even more so in subjects with lower baseline scores. Conclusions OT is effective in supporting olfactory rehabilitation and interventions targeted to verbal semantic fluency. However, it may be prone to a ceiling effect, being efficient in subjects presenting with lower baseline olfactory performance and lower verbal semantic fluency.

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Olfactory Ensheathing Cells Mediate Neuroplastic Mechanisms After Olfactory Training in Mouse Model

American Journal of Rhinology and Allergy ◽

10.1177/1945892419885036 ◽

2019 ◽

Vol 34 (2) ◽

pp. 217-229 ◽

Cited By ~ 1

Author(s):

Boo-Young Kim ◽

JuYeon Park ◽

EuiJin Kim ◽

ByungGuk Kim

Keyword(s):

Olfactory System ◽

Olfactory Receptors ◽

Olfactory Ensheathing Cells ◽

Control Group ◽

Messenger Ribonucleic Acid ◽

Beneficial Effects ◽

Olfactory Neuroepithelium ◽

Ensheathing Cells ◽

Olfactory Training ◽

Stimulation Of

Background Several studies have reported beneficial effects of olfactory training (OT) on the olfactory nervous system. However, the mechanisms underlying the regeneration of the olfactory system induced by OT are still under investigation. Objectives To determine the key mechanisms involved in the olfactory system recovery and to assess the neuroplastic effects of OT. Methods Thirty healthy female C57BL/6 mice were randomly allocated to 4 groups: control, n = 6; anosmia (no treatment), n = 8; OT, n = 8; and steroid treatment; n = 8. Except for the control group, mice were administered 3-methylindole. Anosmia was assessed using a food-finding test (FFT). The olfactory neuroepithelium was for histological examinations, gene ontology with pathway analyses, RNA, and protein studies. Results FFT was significantly reduced at 3 weeks in the OT mice versus steroids (78.27 s vs 156.83 s, P < .008) and controls (78.27 s vs 13.14 s, P < .003), although final outcome in the FFT was similar in these groups. Expression of olfactory and neurogenesis marker was higher in the olfactory neuroepithelium of the OT group than in the anosmia group without treatment. The mechanisms underlying olfactory regeneration might be related to early olfactory receptor stimulation, followed by neurotrophic factor stimulation of neuronal plasticity. Conclusion OT can improve olfactory function and accelerate olfactory recovery. The mechanisms underlying olfactory regeneration might be related to an initial stimulation of olfactory receptors followed by neurogenesis. Olfactory ensheathing cells might play an important role in olfactory regeneration following OT, based on the observed changes in messenger ribonucleic acid (mRNA) and protein expression, as well as the findings of the gene analysis.

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Beneficial Effects of Akkermansia muciniphila Are Not Associated with Major Changes in the Circulating Endocannabinoidome but Linked to Higher Mono-Palmitoyl-Glycerol Levels as New PPARα Agonists

Cells ◽

10.3390/cells10010185 ◽

2021 ◽

Vol 10 (1) ◽

pp. 185

Author(s):

Clara Depommier ◽

Rosa Maria Vitale ◽

Fabio Arturo Iannotti ◽

Cristoforo Silvestri ◽

Nicolas Flamand ◽

...

Keyword(s):

Metabolic Syndrome ◽

Univariate Analysis ◽

Metabolic Effects ◽

Peroxisome Proliferator ◽

Peroxisome Proliferator Activated Receptor ◽

Akkermansia Muciniphila ◽

Beneficial Effects ◽

Daily Ingestion ◽

Before And After ◽

Palmitoyl Glycerol

Akkermansia muciniphila is considered as one of the next-generation beneficial bacteria in the context of obesity and associated metabolic disorders. Although a first proof-of-concept of its beneficial effects has been established in the context of metabolic syndrome in humans, mechanisms are not yet fully understood. This study aimed at deciphering whether the bacterium exerts its beneficial properties through the modulation of the endocannabinoidome (eCBome). Circulating levels of 25 endogenous endocannabinoid-related lipids were quantified by liquid chromatography with tandem mass spectrometry (LC-MS/MS) in the plasma of overweight or obese individuals before and after a 3 months intervention consisting of the daily ingestion of either alive or pasteurized A. muciniphila. Results from multivariate analyses suggested that the beneficial effects of A. muciniphila were not linked to an overall modification of the eCBome. However, subsequent univariate analysis showed that the decrease in 1-Palmitoyl-glycerol (1-PG) and 2-Palmitoyl-glycerol (2-PG), two eCBome lipids, observed in the placebo group was significantly counteracted by the alive bacterium, and to a lower extent by the pasteurized form. We also discovered that 1- and 2-PG are endogenous activators of peroxisome proliferator-activated receptor alpha (PPARα). We hypothesize that PPARα activation by mono-palmitoyl-glycerols may underlie part of the beneficial metabolic effects induced by A. muciniphila in human metabolic syndrome.

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Reduction in mobility and COVID-19 transmission

Nature Communications ◽

10.1038/s41467-021-21358-2 ◽

2021 ◽

Vol 12 (1) ◽

Cited By ~ 7

Author(s):

Pierre Nouvellet ◽

Sangeeta Bhatia ◽

Anne Cori ◽

Kylie E. C. Ainslie ◽

Marc Baguelin ◽

...

Keyword(s):

Predictive Ability ◽

Control Measures ◽

Social Distancing ◽

Beneficial Effects ◽

Mobility Data ◽

Strict Control ◽

Before And After ◽

Proxy Measure ◽

Lower Transmission ◽

The Relationship

AbstractIn response to the COVID-19 pandemic, countries have sought to control SARS-CoV-2 transmission by restricting population movement through social distancing interventions, thus reducing the number of contacts. Mobility data represent an important proxy measure of social distancing, and here, we characterise the relationship between transmission and mobility for 52 countries around the world. Transmission significantly decreased with the initial reduction in mobility in 73% of the countries analysed, but we found evidence of decoupling of transmission and mobility following the relaxation of strict control measures for 80% of countries. For the majority of countries, mobility explained a substantial proportion of the variation in transmissibility (median adjusted R-squared: 48%, interquartile range - IQR - across countries [27–77%]). Where a change in the relationship occurred, predictive ability decreased after the relaxation; from a median adjusted R-squared of 74% (IQR across countries [49–91%]) pre-relaxation, to a median adjusted R-squared of 30% (IQR across countries [12–48%]) post-relaxation. In countries with a clear relationship between mobility and transmission both before and after strict control measures were relaxed, mobility was associated with lower transmission rates after control measures were relaxed indicating that the beneficial effects of ongoing social distancing behaviours were substantial.

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Brain Training and Sulforaphane Intake Interventions Separately Improve Cognitive Performance in Healthy Older Adults, Whereas a Combination of These Interventions Does Not Have More Beneficial Effects: Evidence from a Randomized Controlled Trial

Nutrients ◽

10.3390/nu13020352 ◽

2021 ◽

Vol 13 (2) ◽

pp. 352

Author(s):

Rui Nouchi ◽

Qingqiang Hu ◽

Toshiki Saito ◽

Natasha Yuriko dos Santos Kawata ◽

Haruka Nouchi ◽

...

Keyword(s):

Older Adults ◽

Active Control ◽

Processing Speed ◽

Cognitive Functions ◽

Controlled Trial ◽

Memory Performance ◽

Brain Training ◽

Beneficial Effects ◽

Before And After ◽

Double Blinded

Background: Earlier studies have demonstrated that a single-domain intervention, such as a brain-training (BT) game alone and a sulforaphane (SFN) intake, positively affects cognition. This study examined whether a combined BT and SFN intake intervention has beneficial effects on cognitive function in older adults. Methods: In a 12-week double-blinded randomized control trial, 144 older adults were randomly assigned to one of four groups: BT with SFN (BT-S), BT with placebo (BT-P), active control game (AT) with SFN (AT-S), and active control game with placebo (AT-P). We used Brain Age in BT and Tetris in AT. Participants were asked to play BT or AT for 15 min a day for 12 weeks while taking a supplement (SFN or placebo). We measured several cognitive functions before and after the intervention period. Results: The BT (BT-S and BT-P) groups showed more improvement in processing speed than the active control groups (AT-S and AT-P). The SFN intake (BT-S and AT-S) groups recorded significant improvements in processing speed and working memory performance unlike the placebo intake groups (BT-P and AT-P). However, we did not find any evidence of the combined intervention’s beneficial effects on cognition. Discussion: We discussed a mechanism to improve cognitive functions in the BT and SFN alone interventions.

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Hemodynamic Responses in Lower Limb Lymphedema Patients Undergoing Physical Therapy

Biology ◽

10.3390/biology10070642 ◽

2021 ◽

Vol 10 (7) ◽

pp. 642

Author(s):

Bianca Brix ◽

Olivier White ◽

Christian Ure ◽

Gert Apich ◽

Paul Simon ◽

...

Keyword(s):

Physical Therapy ◽

Lymphatic System ◽

Orthostatic Intolerance ◽

Hemodynamic Responses ◽

Stand Test ◽

Beneficial Effects ◽

Sit To Stand ◽

Complete Decongestive Therapy ◽

Before And After ◽

Baseline Values

Background: Lymphedema arises due to a malfunction of the lymphatic system, leading to extensive tissue swelling. Complete decongestive therapy (CDT), which is a physical therapy lasting for 3 weeks and includes manual lymphatic drainages (MLD), leads to fluid mobilization and increases in plasma volume. Here, we investigated hemodynamic responses induced by these fluid shifts due to CDT and MLD. Methods: Hemodynamic parameters were assessed continuously during a sit-to-stand test (5 min baseline, 5 min of standing, and 5 min of recovery). This intervention was repeated on days 1, 2, 7, 14, and 21 of CDT, before and after MLD. Volume regulatory hormones were assessed in plasma samples. Results: A total number of 13 patients took part in this investigation. Resting diastolic blood pressure significantly decreased over three weeks of CDT (p = 0.048). No changes in baseline values were shown due to MLD. However, MLD led to a significant decrease in heart rate during orthostatic loading over all epochs on therapy day 14, as well as day 21. Volume regulatory hormones did not show changes over lymphedema therapy. Conclusion: We did not observe any signs of orthostatic hypotension at rest, as well as during to CDT, indicating that lymphedema patients do not display an elevated risk of orthostatic intolerance. Although baseline hemodynamics were not affected, MLD has shown to have potential beneficial effects on hemodynamic responses to a sit-to-stand test in patients undergoing lymphedema therapy.

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Olfactory Training Using Heavy and Light Weight Molecule Odors

Perception ◽

10.1177/0301006616672881 ◽

2016 ◽

Vol 46 (3-4) ◽

pp. 343-351 ◽

Cited By ~ 11

Author(s):

Sophia C. Poletti ◽

Elisabeth Michel ◽

Thomas Hummel

Keyword(s):

Molecular Weight ◽

Olfactory Dysfunction ◽

Light Weight ◽

Short Term ◽

Olfactory Loss ◽

Short Term Exposure ◽

Before And After ◽

Phenyl Ethyl Alcohol ◽

A Prospective Study ◽

Olfactory Training

Background Repeated short-term exposure to odors is known to improve olfaction in patients with acquired olfactory dysfunction. The aim was to find out whether differences in molecular weight of odors used for olfactory training influences olfaction. We hypothesized a greater improvement following training with light weight molecule (LWM) odors. Methods A prospective study was performed in patients with posttraumatic (PTOL) and postviral olfactory loss (PVOL). Olfactory training was performed over a period of 5 months. One group ( n = 48) used four odors containing heavy weight molecules (HWM; >150 g/mol) and another ( n = 48) containing LWM (<150 g/mol). Olfaction was tested before and after the training using the Sniffin’ Sticks test. Results Olfactory training was associated with olfactory improvement, with the improvement in PVOL patients being three times greater than that seen in the PTOL group. Compared with LWM training, HWM training was associated with a significantly greater improvement in Phenyl Ethyl Alcohol (PEA) threshold scores in PVOL patients; however, no such improvement could be shown for other subtests or in PTOL patients. Conclusion Overall, training was associated with olfactory improvement. With the exception of threshold scores in PVOL, there were no significant differences between LWM and HWM groups.

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Plant Foods Rich in Antioxidants and Human Cognition: A Systematic Review

Antioxidants ◽

10.3390/antiox10050714 ◽

2021 ◽

Vol 10 (5) ◽

pp. 714

Author(s):

Luciana Baroni ◽

Anna Rita Sarni ◽

Cristina Zuliani

Keyword(s):

Young Adult ◽

Human Cognition ◽

Cognitive Assessments ◽

Cross Sectional ◽

Cognitive Domains ◽

Plant Foods ◽

Beneficial Effects ◽

System Integrity ◽

Plant Antioxidants ◽

The Impact

Oxidative stress can compromise central nervous system integrity, thereby affecting cognitive ability. Consumption of plant foods rich in antioxidants could thereby protect cognition. We systematically reviewed the literature exploring the effects of antioxidant-rich plant foods on cognition. Thirty-one studies were included: 21 intervention, 4 cross-sectional (one with a cohort in prospective observation as well), and 6 prospective studies. Subjects belonged to various age classes (young, adult, and elderly). Some subjects examined were healthy, some had mild cognitive impairment (MCI), and some others were demented. Despite the different plant foods and the cognitive assessments used, the results can be summarized as follows: 7 studies reported a significant improvement in all cognitive domains examined; 19 found significant improvements only in some cognitive areas, or only for some food subsets; and 5 showed no significant improvement or no effectiveness. The impact of dietary plant antioxidants on cognition appears promising: most of the examined studies showed associations with significant beneficial effects on cognitive functions—in some cases global or only in some specific domains. There was typically an acute, preventive, or therapeutic effect in young, adult, and elderly people, whether they were healthy, demented, or affected by MCI. Their effects, however, are not attributable only to anti-oxidation.

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Cyclosporine increases ischemia-induced endothelial progenitor cell mobilization through manipulation of the CD26 system

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00543.2007 ◽

2008 ◽

Vol 294 (3) ◽

pp. R811-R818 ◽

Cited By ~ 31

Author(s):

Chao-Hung Wang ◽

Wen-Jin Cherng ◽

Ning-I Yang ◽

Chia-Ming Hsu ◽

Chi-Hsiao Yeh ◽

...

Keyword(s):

Critical Role ◽

Serum Levels ◽

Blood Levels ◽

Short Term ◽

Endothelial Progenitor ◽

Beneficial Effects ◽

Dpp Iv ◽

Before And After ◽

Cell Mobilization

Cyclosporin A (CsA) improves the success rate of transplantation. The CD26/dipeptidylpeptidase IV (DPP IV) system plays a critical role in mobilizing endothelial progenitor cells (EPCs) from bone marrow. This study investigated whether CsA manipulates CD26/DPP IV activity and increases EPC mobilization. C57BL/6 mice were divided into control and CsA-treated groups. Before and after hindlimb ischemia was induced, circulating EPC number and serum levels of different cytokines were measured. Compared with the controls, CsA treatment significantly increased the blood levels of stroma-derived factor-1α and stem cell factor after ischemic stress ( P < 0.001). The CsA group displayed a significant increase in the number of circulating EPCs (sca-1+KDR+ and c-kit+CD31+ EPCs, both P < 0.05). In vivo, CsA caused a significant increase in the numbers of EPCs incorporated into the Matrigel and ischemic limbs ( P < 0.05). In the peripheral blood, CsA significantly decreased CD26+ cell numbers and attenuated the plasma CD26/DPP IV activity ( P < 0.001). Furthermore, short-term CsA treatment significantly improved the perfusion of ischemic limbs and decreased the spontaneous digital amputation rate. In summary, CsA manipulates the mobilization of EPCs into the circulation via the CD26/DPP IV system. Short-term CsA treatment has beneficial effects on angiogenesis of ischemic tissues.

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The Usefulness of Impedance Cardiography for Predicting Beneficial Effects of Cardiac Rehabilitation in Patients with Heart Failure

BioMed Research International ◽

10.1155/2013/595369 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Grzegorz Gielerak ◽

Paweł Krzesiński ◽

Ewa Piotrowicz ◽

Ryszard Piotrowicz

Keyword(s):

Heart Failure ◽

Cardiac Rehabilitation ◽

Exercise Tolerance ◽

Impedance Cardiography ◽

The Other ◽

Pronounced Increase ◽

Fluid Content ◽

Beneficial Effects ◽

Patients With Heart Failure ◽

Before And After

Aim. Cardiac rehabilitation (CR) is an important part of heart failure (HF) treatment. The aim of this paper was to evaluate if thoracic fluid content (TFC) measured by impedance cardiography (ICG) is a useful parameter for predicting the outcome of CR.Methods. Fifty HF patients underwent clinical and noninvasive haemodynamic (TFC) assessments before and after 8-week CR.Results. As a result of CR, the patients’ exercise tolerance improved, especially in terms of peak VO2(18.7 versus 20.8 mL × kg−1× min−1;P=0.025). TFC was found to identify patients with significantly improved peak VO2after CR. “High TFC” patients (TFC > 27.0 kOhm−1), compared to those of “low TFC” (TFC < 27.0 kOhm−1), were found to have more pronounced increase in peak VO2(1.3 versus 3.1 mL × kg−1× min−1;P=0.011) and decrease in TFC (4.0 versus 0.7 kOhm−1;P<0.00001). On the other hand, the patients with improved peak VO2(n=32) differed from those with no peak VO2improvement in terms of higher baseline TFC values (28.4 versus 25.3 kOhm−1;P=0.039) and its significant decrease after CR (2.7 versus 0.2 kOhm−1;P=0.012).Conclusions. TFC can be a useful parameter for predicting beneficial effects of CR worth including in the process of patients’ qualification for CR.

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Parametric Studies of Pipe Diffuser on Performance of a Highly Loaded Centrifugal Compressor

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4027867 ◽

2014 ◽

Vol 136 (12) ◽

Cited By ~ 2

Author(s):

Ge Han ◽

Xingen Lu ◽

Shengfeng Zhao ◽

Chengwu Yang ◽

Junqiang Zhu

Keyword(s):

Centrifugal Compressor ◽

Performance Enhancement ◽

Detailed Comparison ◽

Flow Distortion ◽

Flow Solver ◽

Beneficial Effects ◽

Physical Mechanisms ◽

Parametric Studies ◽

Compressor Performance ◽

Highly Loaded

Pipe diffusers with several different geometries were designed for a highly loaded centrifugal compressor originally using a wedge diffuser. Parametric studies on the effect of pipe diffuser performance of a highly loaded centrifugal compressor by varying pipe diffuser inlet-to-impeller exit radius ratio, throat length, divergence angle, and throat area on centrifugal compressor performance were performed using a state-of-the-art multiblock flow solver. An optimum design of pipe diffuser was obtained from the parametric study, and the numerical results indicate that this pipe diffuser has remarkable advantageous effects on the compressor performance. Furthermore, a detailed comparison of flow visualization between the pipe diffuser and the wedge diffuser was conducted to identify the physical mechanism that account for the beneficial effects of the pipe diffuser on the performance and stability of the compressor. It was found that the performance enhancement afforded by the pipe diffuser is a result of the unique diffuse inlet flow pattern. Alleviating flow distortion in the diffuser inlet and reducing the possibility of a flow separation in discrete passages are the physical mechanisms responsible for improving the highly loaded centrifugal compressor performance.

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