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Objective: Our aim was to investigate the relation between unilateral hippocampal and/or nigral alpha-synucleinopathy and cognitive dysfunction, anxiety and anhedonia. Materials and Methods: Female Sprague-Dawley rats were stereotactically injected adeno-associated viruses carrying alpha-synuclein (α-syn) into unilateral dentate gyrus (DG), substantia nigra (SN) or both SN + DG. The animals were tested for motor functions and memory, spatial learning, anxiety and hedony. Levels of α-syn and synaptophysin were evaluated by Western blot (WB) analysis. Results: In apomorphine-induced rotation test, a mild motor dysfunction was found in SN-α-syn group compared to control. DG- α-syn group showed memory impairment in novel object recognition test. All the α-syn injected groups spent more time to find the platform compared to controls in Morris water maze but this difference did not reach statistical significance. DG-α-syn group consumed more sucrose solution in sucrose consumption test and spent more time on the open arm in elevated plus maze, while the opposite was observed in SN-α-syn group compared to controls. We showed α-syn protein expression in the injected areas of all α-syn groups by WB and immunohistochemical staining. In WB analysis, both hippocampal and striatal synaptophysin expression levels were lower in the α-syn groups compared to controls. Conclusion: Parkinson’s disease (PD) is characterized by both motor and non-motor symptoms (NMS). However, an animal model recapitulating NMS with the background of dopaminergic denervation is still lacking. This model may help to investigate hippocampal α-syn pathology correlated especially with cognitive dysfunction and other NMS of PD.

INTRODUCTION: Our aim is to reduce the side effects and increase the efficiency of donepezil by formulating donepezil-loaded poly(lactic-co-glycolic acid)-block-poly(ethylene glycol) nanoparticles (NPs) directly targeting amyloid beta (Aβ) fibrils in the brain and evaluate behavioral changes in this fibril model of AD. METHODS: AD model was developed by intracerebroventricular injection of pre-aggregated β25-35 fibrils. Rats were intravenously administered either solvent, donepezil-loaded NPs (15µg/kg) or free donepezil (1mg/kg) 3 times for a week except for naïve controls. The effect of treatments on anxiety, motor functions, and cognitive functions was tested by elevated plus maze, locomotor activity, novel object recognition, and Morris’s water maze tests, respectively. RESULTS: Accumulation of Aβ25-35 fibrils in brain sections was confirmed. Anxiety-like behavior was observed in the Aβ Alzheimer and free donepezil treatment groups while donepezil-loaded NP treatment showed hypo-anxiety-like behavior. Donepezil-loaded NPs were successful in treatment of short-term memory deficit better than free donepezil injection. In Morris’s water maze, both donepezil-loaded NPs and free donepezil groups found the platform in shorter time compared to Aβ Alzheimer group. In locomotor activity test, both donepezil treated groups moved less than the Aβ Alzheimer group and naïve controls. After the pharmacological experiments, acetylcholinesterase activity was determined and showed an increase in Aβ Alzheimer group compared to controls. Donepezil-loaded NPs inhibited the acetylcholinesterase activity more efficiently than the free donepezil group. CONCLUSION: Targeting with donepezil-loaded PLGA-b-PEG-NPs increases efficiency, helps to inhibit acetylcholinesterase activity more substantially, improves cognitive decline due to its longer duration of action and destabilizing effect on amyloid fibrils.

Parkinson’s disease (PD) is a progressive disease due to dopaminergic cell loss in the substantia nigra and dopaminergic terminal lost in the striatum, which is the projection area of substantia nigra. It is characterized by resting tremor, bradykinesia, rigidity, and postural instability. In PD, non-motor symptoms such as cognitive impairment, anhedonia, apathy, and autonomic nervous system impairments affect quality of life as much as motor symptoms. PD may affect multiple systems and the underlying mechanisms are not known. However, developing new methods of treatment to slow or stop the rate of disease progression, to lessen or to cure the symptoms is crucial. The aim of this review was to discuss the alternative treatments that may be useful for both motor and non-motor symptoms. Symptomatic treatments with dopaminergic drugs aim to relieve motor symptoms and to increase the patient’s life standards for a limited time. However, possible neuroprotective treatments that inhibit neuronal cell death can extend life span and provide higher quality of life. Lewy bodies, which are formed mainly from misfolded and native alpha-synuclein protein, is a pathologic hallmark of PD. Therefore, inhibiting the protein misfolding or clearing the aggregates could be a promising new therapeutic approach for the disease.

Precipitation with polyelectrolytes is a promising alternative to conventional methods for purification of monoclonal antibodies (mAb). This study focuses on clarification of a monoclonal antibody by precipitation of the model impurity bovine serum albumin (BSA) with cationic polyelectrolytes. Different types of cationic polyelectrolytes with different functional amine groups and molecular weights are screened for their capability to precipitate BSA in mixture with mAb. Due to the high BSA depletion and mAb recovery achieved, two cationic polyelectrolytes, polyethyleneimine (PEI) and polyallylamine (PAA) with a molecular weight of 65 kDa were selected as most suitable precipitation agents. Additionally, influences of different parameters (polyelectrolyte, BSA and NaCl concentration and pH value) were analyzed by the use of design of experiments (DoE). Herewith, a fast identification of influencing factors and factor interaction was achieved. With DoE, two regression models for the analysis of BSA depletion in dependence of influencing factors were established. This enabled the analysis of the robustness of precipitation as initial clarification step of downstream process of mAb.

Background Cognitive dysfunction is one of the most disabling non-motor symptoms of Parkinson's disease (PD), though its pathological correlates still remain elusive. Hippocampal Lewy pathology has recently been correlated by compelling evidence from post-mortem and imaging studies. Animal models recapitulating cognitive impairment in PD are essential to better understand the underlying pathophysiology. To investigate the hippocampal involvement in cognitive dysfunction of PD, we generated an experimental model by inducing midbrain and hippocampal α-synuclein pathology simultaneously. Methods Rats were injected either with human α-synuclein or green fluorescent protein (GFP) expressing adeno-associated viral vectors (AAV), or saline bilaterally into substantia nigra (SN) and dentate gyrus (DG). A group of untreated animals were used as naive controls. Cognitive and behavioral changes were evaluated with tests probing for spatial learning, short-term memory, anxiety and hedonistic behavior. Immunohistochemical staining, immunoblotting and stereological analysis were performed for pathological characterization. Results Bilateral α-synuclein overexpression in SN and DG led to mild but significant motor impairment as well as dysfunctions in short-term memory and spatial learning. There was no hedonistic deficit, whereas a hypo-anxious state was induced. While stereological analysis revealed no significant neuronal loss in any sectors of cornu ammonis, there was considerable decrease (43%) in TH+-neurons in SN pars compacta supporting the well-known vulnerability of nigral dopaminergic neurons to α-synuclein mediated neurodegeneration. On the other hand, synaptophysin levels decreased in similar amounts both in striatum and hippocampus, suggesting comparable synaptic loss in target areas. Interestingly, phosphorylated-S129-α-synuclein staining revealed significant expression in CA2 characterized by more mature and dense cellular accumulations compared to CA1-CA3 sub-regions displaying more diffuse grain-like aggregates, suggesting preferential susceptibility of CA2 to produce α-synuclein induced pathology. Conclusion Bilateral α-synuclein overexpression in DG and SN reproduced partial motor and hippocampus related cognitive deficits. Using this model, we showed a predisposition of CA2 for pathological α-synuclein accumulation, which may provide further insights for future experimental and clinical studies.

Acne vulgaris is one of the most common diseases of the youth. Systemic isotretinoin is the only drug which acts on all of the etiopathogenic mechanisms of acne. Isotretinoin has some well-known side effects. Besides these, there is a suspicion whether it affects fertility or not. Previously, we conducted a study about isotretinoin's effect on ovarian reserve which showed deteriorative reserve. In this study, we aimed to evaluate the long-term effects of systemic isotretinoin on female fertility.Of the 82 female patients who were enrolled in the first study, 79 patients were included in this study. Twelve months after the end of systemic isotretinoin treatment, patients were reevaluated by using the same parameters which include anti-Mullerian hormone (AMH), ovarian volume (OV), antral follicle count (AFC), follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol, free testosterone and total testosterone.The changes in the mean AMH, OV and AFC were statistically significant between the sixth and eighteenth months (the end of systemic isotretinoin treatment and 12 months treatment free). The mean AMH, OV and AFC values at the beginning and at the 18th month were statistically similar.The deteriorative effects of systemic isotretinoin treatment on ovarian reserve, which can be accepted as an indicator of female fertility, diminish in time.

Background/objective: Acne vulgaris is one of the most common diseases of the youth. Systemic isotretinoin is the only drug which acts on all of the etiopathogenic mechanisms of acne. Isotretinoin has some well-known side effects. Besides these, there is a suspicion whether it causes infertility or not. In this study, we aimed to evaluate the effects of systemic isotretinoin on male fertility.Methods: Eighty one male patients, who were older than 18 years of age, and had severe or refractory acne vulgaris were included in the study. They were given a total dose of 120 mg/kg of systemic isotretinoin over a period of six months. Before and after the study, the spermiogram parameters of the patients were evaluated to show any possible effect on male fertility. The patients' total testosterone, follicle stimulating hormone and luteinizing hormone levels were also evaluated.Results: All of the spermiogram parameters changed positively (p

WOS: 000229817600006 The interaction of pentoxifylline (PTX) with Zn(II) in the presence and absence of cysteine at physiological pH (7.40) was investigated for the first time by square-wave and cyclic voltammetry techniques. The Zn( II) - PTX complex was found to be an electroinactive inert complex, the composition of the formed complex is 1 : 1 ( metal : ligand), and the logarithm of its stability constant ( log beta(1 : 1)) was determined as 3.46 by direct monitoring of the current of free zinc( II). The logarithm of the stability constant ( log beta(1 : 2)) and stoichiometry of the complexation of Zn( II) with cysteine were determined to be 9.94 and 1 : 2, respectively. The stability constants were in agreement with those calculated from electronic spectral data. In the presence of cysteine, Zn( II) - PTX dissociated and an irreversible peak for Zn( II) - cysteine appeared at - 1.342 V. Cysteine prevents complex formation of Zn( II) with PTX.

The interaction of pentoxifylline (PTX), a methylxanthine derivative drug, with cysteine on the hanging mercury drop electrode studied by square-wave voltammetry, cyclic voltammetry and UV-Vis spectroscopy at phosphate buffer (pH 7.4) in the presence and absence of UV irradiation. The addition of PTX to cysteine solution results in the decrease of peak currents of mercurous cysteine thiolate and the shift of its voltammetric reversible peak towards positive potentials. Electrochemical data indicated a 1:1 molecular complex formation of PTX with cysteine by means of electrostatic interaction and intermolecular forces. For the long UV irradiation times (25–85 min), voltammogram of the cysteine solution gave the reduction peaks of sulphonyl radical (−0.056 V), disulfidic anion (−0.684 V) and free cystine (−0.800 V) due to probably the formation of thiyl radical. With adding of PTX to the UV irradiated cysteine solution, a new peak at −0.292 V was observed. The peak at −0.292 V was also obtained for the cysteine and PTX mixture under UV irradiation, but the peaks of sulphonyl radical and disulphidic anion were no seen. As a result, this irreversible peak at −0.292 V may be assigned to the reduction of an electroactive species which is formed from PTX–cysteine complex under UV irradiation. PTX prevents the formation of thiyl radical and its further oxidation.

The voltammetric behaviour of pentoxifylline (1-(5′-oxohexyl)-3,7-dimethylxanthine, PTX) was studied in several supporting electrolytes (Britton–Robinson buffer of pH 2–12, 0.1 M NH3/NH4Cl buffer (pH 9.08), 0.1 M Na2B4O7 (pH 9.30), 0.1 M KCl (pH 6.22). At 0.1 M Britton–Robinson buffer (pH 7.46) PTX gives two peaks at −0.150 V and −1.524 V, respectively. At low pH values (pH < 5.50), the second peak was obscured by the hydrogen evolution while the first peak is well defined at 0.1 M KNO3 supporting electrolyte (pH 6.22). The potential of the second peak is practically pH-independent in the pH range of 6.50–11.00. The peaks (at −0.150 V and −1.524 V) are attributed to the reduction of Hg(I)-PTX complex and carbonyl group at 5′-oxohexyl moiety of the molecule, respectively. The relationship between peak current of carbonyl group and concentration of PTX is linear in 1.48 × 10−5 − 1.34 × 10−4 M concentration range in 0.1 M KCl (pH 6.22). It was observed that PTX has adsorption/desorption characteristics. A plausible mechanism is proposed for the electrode reaction of PTX on the mercury electrode.