The effect of monoamines reuptake inhibitors on aerobic exercise performance in bank voles from a selection experiment

Exercise performance depends on both physiological abilities (e.g., muscle strength) and behavioral characteristics (e.g., motivation). We tested the hypothesis that evolution of increased aerobic exercise performance can be facilitated by evolution of neuropsychological mechanisms responsible for motivation to undertake physical activity. We used a unique model system: lines of bank voles Myodes glareolus selected for high swim-induced aerobic metabolism ("aerobic" A lines). In generation 21, voles from the 4 A lines achieved a 57% higher "voluntary maximum" swim-induced aerobic metabolism (VO_{2}swim) than voles from 4 unselected, "control" C lines. In C lines, VO_{2}swim was 9% lower than the maximum forced-exercise aerobic metabolism (VO_{2}run; P=0.007), while in A lines it was even higher than VO_{2}run, although not significantly (4%, P=0.15). Thus, we hypothesized that selection changed both the aerobic capacity and the neuronal mechanisms behind motivation to undertake activity. We investigated the influence of reuptake inhibitors of dopamine (DARI), serotonin (SSRI), and norepinephrine (NERI) on VO_{2}swim. The drugs decreased VO_{2}swim both in C and A lines (% decrease compared with saline: DARI 8%, P<0.001; SSRI 6%, P<0.001; NERI 8%, P<0.001), but the proportional response differed between selection directions only for NERI (stronger effect in C lines: P=0.008) and the difference was marginally non-significant for SSRI (P=0.07) and DARI (P=0.06). Thus, the results suggest that all the 3 monoamines are involved in signaling pathways controlling the motivation to be active and that norepinephrine could have played a role in the evolution of increased aerobic exercise performance in our animal model

Is Experimental Evolution of an Increased Aerobic Exercise Performance in Bank Voles Mediated by Endocannabinoid Signaling Pathway?

The level of physical activity achieved in a given situation depends on both physiological abilities and behavioral characteristics (motivation). We used a unique animal model to test a hypothesis that evolution of an increased aerobic exercise performance can be facilitated by evolution of motivation to undertake physical activity, mediated by brain endocannabinoid system. Bank voles (Myodes glareolus) from “aerobic” A lines selected for 22 generations for high swim-induced aerobic metabolism (VO2swim) achieved 65% higher “voluntary maximum” VO2swim than voles from unselected, “control” C lines. In C lines, VO2swim was 24% lower than the maximum forced-running aerobic metabolism (VO2run), while in A lines VO2swim and VO2run were practically the same. Thus, the selection changed both the aerobic capacity and motivation to exercise at the top performance level. We applied a pharmacological treatment manipulation to test a hypothesis that the endocannabinoid signaling pathway 1) affects the voles performance in the aerobic exercise trials, and 2) has been modified in the selection process. Administration of the CB1 receptor antagonist (Rimonabant) did not affect the level of metabolism, but administration of the endocannabinoid reuptake inhibitor (AM404) decreased VO2swim both in A and C lines (4%, p = 0.03) and tended to decrease VO2run (2%, p = 0.07). The significant effect of AM404 suggests the involvement of endocannabinoids in signaling pathways controlling the motivation to be active. However, the response to AM404 did not differ between A and C lines (interaction effect, p ≥ 0.29). Thus, the results did not provide a support to the hypothesis that modifications of endocannabinoid signaling have played a role in the evolution of increased aerobic exercise performance in our experimental evolution model system.Summary StatementThe results corroborated involvement of endocannabinoids in the regulation of physical activity, but did not support the hypothesis that modification of endocannabinoid signaling played a role in the evolution of increased aerobic exercise performance in our experimental evolution model

Mechanizmy neurofizjologiczne leżące u podstaw zwiększonej wydolności nornic rudych selekcjonowanych na wysoki metabolizm tlenowy uzyskiwany podczas pływania

Poziom aktywności fizycznej zależy zarówno od biomechanicznych i fizjologicznych ograniczeń organizmu (np, sity mięśni), jak i cech behawioralnych (np. motywacji, która jest "generowana" przez układ nerwowy). Celem pracy było zbadanie, czy ewolucja zwiększonej wydolności tlenowej może być wsparta przez ewolucję motywacji do podjęcia aktywności fizycznej, Hipotezy dotyczące roli sygnalizacji monoaminergicznej (dopaminergicznej, noradrenergicznej, serotoninergicznej) lub endokannabinoidowej w regulacji motywacji do podejmowania wysiłku były testowane w oparciu o unikalny model zwierzęcy - linie nornic rudych (Myodesglareolus) selekcjonowane w kierunku wysokiego tempa metabolizmu tlenowego uzyskiwanego podczas pływania (linie A) oraz nieselekcjonowane linie kontrolne (linie C), W pokoleniu 19 nornice z linii A osiągnęły o 61% wyższy metabolizm tlenowy podczas pływania (VChs^m) niż nornice z linii C. Ponieważ podczas pomiarów nornice mogły energicznie pływać lub po prostu unosić się na powierzchni wody, poziom VO2swim zależał zarówno od wydolności tlenowej jak i motywacji do podjęcia intensywnej aktywności. Poziom metabolizmu osiągany podczas wysiłku, który zależy głównie od wydolności tlenowej (wymuszony bieg na bieżni, VO2^rn) był wyższy niż VChswim u nornic z linii C (korygowane na masę ciała LSM ± SE [mlC^/min]: bieg: 4,73±0,13, pływanie: 4,31±0,13; p=0,008), podczas gdy nornice z linii A osiągnęły podobny poziom VO2run i VO2 swim (bieg: 6,09±0,13, pływanie: 6,31±0,13; p=0,13), W kolejnych pokoleniach wyniki były podobne, Zatem pod wpływem selekcji zmianie uległa zarówno wydolność tlenowa, jak i mechanizmy neuronalne odpowiedzialne za motywację do podjęcia intensywnej aktywności fizycznej, W celu testowania hipotezy badano wpływ manipulacji farmakologicznej na VO2 swim, Użyto nieselektywnego inhibitora wychwytu zwrotnego (RI) dopaminy/noradrenaliny (DARI/NERI, bupropion), selektywnych RI dopaminy (DARI, wanokseryna), serotoniny (SSRI, fluoksetyna), noradrenaliny (NERI, reboksetyna) i endokannabinoidów (eCBRI, AM404) oraz antagonistę receptora endokannabinoidowego CB1 (CBlAnta, rimonabant), DARI/NERI i CB1Anta nie wpłynęły znacząco na mierzone cechy, DARI, SSRI, NERI i eCBRI obniżyły poziom VO2 swim u nornic z linii A i C (spadek % w porównaniu z pomiarem po zastrzyku kontrolnym, pozbawionym leku: DARI 8%, p<0,001; SSRI 6%, p<0,001; NERI 8%, p<0,001; eCBRI 4%, p=0,03). Wyniki sugerują, że zarówno sygnalizacja monoaminergiczna jak i endokannabinoidowa bierze udział w kontroli motywacji do podejmowania wysiłku fizycznego, Brak różnicy w odpowiedzi na zastrzyk z DARI, SSRI i eCBRI pomiędzy nonicami z linii A i C sugeruje, że dopamina, serotoninia i endonkannabinoidy nie miały udziału w ewolucji zwiększonej wydolności tlenowej w przedstawionym modelu zwierzęcym. Jednak proporcjondna odpowiedź na lek (stosunek VO2swim uzyskany po zastrzyku zawierającym lek do VO2swim po zastrzyku kontrolnym) różniła się między liniami A i C dla NERI (o 8% silniejszy efekt w liniach C w stosunku do linii A: p = 0,008), Wynik sugeruje, że nora&endina miała udział w ewolucji zwiększonej wydolności tlenowej w przedstawionym modelu zwierzęcym. Ponieważ eksperyment eweolucyjny nadal trwa, wyniki kolejnych badań (np. badanie zawartości neurotransmiterów w tkance mózgowej) mogą pomóc w znalezieniu odpowiedzi na pytanie który mechanizm neurobiologiczny bierze udział w zmienionej motywacji do aktywności nornic z linii A.The level of physical activity achieved in a given situation depends on both physiological abilities (e.g. muscle strength) and behavioral characteristics (e.g. motivation), The objective of the study was to test the hypothesis that evolution of increased aerobic exercise performance can be facilitated by evolution of motivation to undertake physical activity mediated by monoaminergic (dopaminergic, noradrenergic, serotoninergic) or endocannabinoid signaling, The study was based on a unique model: four lines of bank voles (Myodes glareolus) selected for high swim-induced aerobic metabolism ("aerobic" A lines) and four lines of unselected voles ("control" C lines), In generation 19, voles from the A lines achieved 61% higher aerobic metabolism during swimming (VO2swim) than voles from C lines, Because the voles could vigorously swim or just float on the water surface, the level of VO2swim depended both on aerobic capacity and motivation to undertake intensive activity, C-lines voles achieved higher level of metabolism during an exercise that depends mainly on aerobic capacity (forced running, VO2run) than during swimming (mass-adjusted LSM±SE [mlO2/min]; run: 4.73±0.13, swim: 4.31±0.13; p=0,008), while A-lines voles achieved similar VO2run and VO2swim (^m: 6.09±0.13, swim: 6.31±0.13, p=0,13), Thus, the selection changed both aerobic capacity and neuronal mechanisms behind motivation to undertake activity, In a set of pharmacological manipulation experiments the influence of a nonselective reuptake inhibitor (RI) of dopamine/noradrenaline (DARI/NERI, bupropion), selective RIs of dopamine (DARI, vanoxerine), serotonin (SSRI, fluoxetine), noradrenaline (NERI, reboxetine) and endocannabinoids (eCBRI, AM404), and an endocannabinoid receptor CB1 antagonist (CB1Anta, rimonabant) on VO2 swim was investigated, DARI/NERI and CB1Anta had no significant effect on the measured traits, DARI, SSRI, NERI and eCBRI decreased VO2 swim in voles from A and C lines (% decrease compared with saline: DARI 8%, p<0,001; SSRI 6%, p<0,001; NERI 8%, p<0,001; eCBRI 4%, p=0,03), The results suggest that all the three monoamines and endocannabinoids are involved in signaling pathways controlling the motivation to be active, Because there was no significant difference in the response to DARI, SSRI and eCBRI between voles from A and C lines, the results did not support the hypothesis that an alternation of dopaminergic, serotoninergic or endocannabinoid signaling pathway have played a role in the evolution of increased aerobic exercise performance in the experimental evolution model, However, the proportional response (the ratio of a VO2swim achieved after drug to that after vehicle) differed between selection directions in case of NERI (8% stronger effect in C lines when compared to A lines: p=0,008), Thus, noradrenaline could have played a role in the evolution of increased aerobic exercise performance in the animal model, As the selection experiment is continued, further studies (for example analyses of neurotransmitters content in brain tissue) can answer the question which neurobiological mechanism underlies the evolutionary changes in motivation to be active

Evaluation of cytocompatibility and bioactivity of PLGA and PLGA-based nanocomposite biomaterials in osteoblasts’ culture.

The aim of this investigation was to test the biocompatibility of two-dimensional bioresorbable films of poly(lactide-co-glycolide) acid (PLGA) and three-component nanocomposites consisting of PLGA and calcium alginate fibers modified by nanoadditives (nanohydroksyapatite or nanosilica). As the targeted application is bone tissue their effects on cell morphology, proliferation and differentiation were estimated using normal human osteoblasts (NHOst). The composite films supported cell differentiation toward mature osteoblasts while the proliferation of seeded cells was delayed in comparison to the control sample (Thermanox®) and pure PLGA, as revealed by fluorescent microscopy and mineralization test.Celem pracy było zbadanie biozgodności resorbowalnych folii polimerowych PGLA (kopolimer kwasu glikolowego i mlekowego) oraz folii kompozytowych polimerowo-włóknistych, których osnowę stanowił PGLA, a fazę włóknistą alginian wapnia modyfikowany nanododatkami (hydroksyapatytem lub krzemionką). Ponieważ potencjalnym miejscem implantacji badanych biomateriałów jest tkanka kostna ich wpływ na morfologię, proliferację i różnicowanie komórek badano w hodowli komórkowej ludzkich osteoblastów (NHOst). Folie kompozytowe miały korzystny wpływ na różnicowanie komórek, jednak proliferacja osteoblastów przylegających do tych materiałów przebiegała wolniej w porównaniu do próby kontrolnej (Thermanox®) i folii z samego PGLA, na co wskazywały wyniki badań mineralizacji i obserwacje w mikroskopie fluorescencyjnym

Design and Development of a New Type of Hybrid PLGA/Lipid Nanoparticle as an Ursolic Acid Delivery System against Pancreatic Ductal Adenocarcinoma Cells

Despite many attempts, trials, and treatment procedures, pancreatic ductal adenocarcinoma (PDAC) still ranks among the most deadly and treatment-resistant types of cancer. Hence, there is still an urgent need to develop new molecules, drugs, and therapeutic methods against PDAC. Naturally derived compounds, such as pentacyclic terpenoids, have gained attention because of their high cytotoxic activity toward pancreatic cancer cells. Ursolic acid (UA), as an example, possesses a wide anticancer activity spectrum and can potentially be a good candidate for anti-PDAC therapy. However, due to its minimal water solubility, it is necessary to prepare an optimal nano-sized vehicle to overcome the low bioavailability issue. Poly(lactic-co-glycolic acid) (PLGA) polymeric nanocarriers seem to be an essential tool for ursolic acid delivery and can overcome the lack of biological activity observed after being incorporated within liposomes. PLGA modification, with the addition of PEGylated phospholipids forming the lipid shell around the polymeric core, can provide additional beneficial properties to the designed nanocarrier. We prepared UA-loaded hybrid PLGA/lipid nanoparticles using a nanoprecipitation method and subsequently performed an MTT cytotoxicity assay for AsPC-1 and BxPC-3 cells and determined the hemolytic effect on human erythrocytes with transmission electron microscopic (TEM) visualization of the nanoparticles and their cellular uptake. Hybrid UA-loaded lipid nanoparticles were also examined in terms of their stability, coating dynamics, and ursolic acid loading. We established innovative and repeatable preparation procedures for novel hybrid nanoparticles and obtained biologically active nanocarriers for ursolic acid with an IC50 below 20 &micro;M, with an appropriate size for intravenous dosage (around 150 nm), high homogeneity of the sample (below 0.2), satisfactory encapsulation efficiency (up to 70%) and excellent stability. The new type of hybrid UA-PLGA nanoparticles represents a further step in the development of potentially effective PDAC therapies based on novel, biologically active, and promising triterpenoids

Novel Liposomal Formulation of Baicalein for the Treatment of Pancreatic Ductal Adenocarcinoma: Design, Characterization, and Evaluation

Pancreatic cancer (PC) is one of the deadliest cancers so there is an urgent need to develop new drugs and therapies to treat it. Liposome-based formulations of naturally-derived bioactive compounds are promising anticancer candidates due to their potential for passive accumulation in tumor tissues, protection against payload degradation, and prevention of non-specific toxicity. We chose the naturally-derived flavonoid baicalein (BAI) due to its promising effect against pancreatic ductal adenocarcinoma (PDAC) and encapsulated it into a liposomal bilayer using the passive loading method, with an almost 90% efficiency. We performed a morphological and stability analysis of the obtained BAI liposomal formulation and evaluated its activity on two-dimensional and three-dimensional pancreatic cell models. As the result, we obtained a stable BAI-encapsulated liposomal suspension with a size of 100.9 nm ± 2.7 and homogeneity PDI = 0.124 ± 0.02, suitable for intravenous administration. Furthermore, this formulation showed high cytotoxic activity towards AsPC-1 and BxPC-3 PDAC cell lines (IC50 values ranging from 21 ± 3.6 µM to 27.6 ± 4.1 µM), with limited toxicity towards normal NHDF cells and a lack of hemolytic activity. Based on these results, this new BAI liposomal formulation is an excellent candidate for potential anti-PDAC therapy