Multi-target-directed ligands: application to the Alzheimer's disease

The MTDL (multi-target-directed ligand) design strategy is used to develop single chemical entities that are able to simultaneously modulate multiple targets. The development of such compounds might disclose new avenues for the treatment of a variety of pathologies (e.g. cancer, AIDS, neurodegenerative diseases), for which an effective cure is urgently needed. This strategy has been successfully applied to Alzheimer’s disease (AD) due to its multifactorial nature, involving cholinergic dysfunction, amyloid aggregation, and oxidative stress. Despite many biological entities have been recognized as possible AD-relevant, only four achetylcholinesterase inhibitors (AChEIs) and one NMDA receptor antagonist are used in therapy. Unfortunately, such compounds are not disease-modifying agents behaving only as cognition enhancers. Therefore, MTDL strategy is emerging as a powerful drug design paradigm: pharmacophores of different drugs are combined in the same structure to afford hybrid molecules. In principle, each pharmacophore of these new drugs should retain the ability to interact with its specific site(s) on the target and, consequently, to produce specific pharmacological responses that, taken together, should slow or block the neurodegenerative process. To this end, the design and synthesis of several examples of MTDLs for combating neurodegenerative diseases have been published. This seems to be the more appropriate approach for addressing the complexity of AD and may provide new drugs for tackling the multifactorial nature of AD, and hopefully stopping its progression. According to this emerging strategy, in this work thesis different classes of new molecular structures, based on the MTDL approach, have been developed. Moreover, curcumin and its constrained analogs have currently received remarkable interest as they have a unique conjugated structure which shows a pleiotropic profile that we considered a suitable framework in developing MTDLs. In fact, beside the well-known direct antioxidant activity, curcumin displays a wide range of biological properties including anti-inflammatory and anti-amyloidogenic activities and an indirect antioxidant action through activation of the cytoprotective enzyme heme oxygenase (HO-1). Thus, since many lines of evidence suggest that oxidative stess and mitochondria impairment have a cental role in age-related neurodegenerative diseases such as AD, we designed mitochondria-targeted antioxidants by connecting curcumin analogs to different polyamine chains that, with the aid of electrostatic force, might drive the selected antioxidant moiety into mitochondria.

Valutazione della proteinuria e del follow-up clinico e clinicopatologico in cani affetti da Leishmaniosi canina

Introduzione: la leishmaniosi canina (CanL) è una malattia infettiva, trasmessa da vettore e sostenuta da un protozoo, la Leishmania infantum. La CanL ha assunto sempre più importanza sia in medicina veterinaria che in medicina umana. La leishmaniosi è fortemente associata allo sviluppo di una nefropatia cronica. Disegno dello studio: studio di coorte retrospettivo. Obiettivo: individuare le alterazioni clinico-patologiche prevalenti al momento dell’ammissione e durante il follow-up del paziente, per identificare quelle con un valore prognostico maggiore. Materiali e metodi: 167 cani, per un totale di 187 casi trattati, con diagnosi sierologica e/o citologica di Leishmaniosi e dati ematobiochimici completi, elettroforesi sierica, analisi delle urine e biochimica urinaria comprensiva di proteinuria (UPC) ed albuminuria (UAC), profilo coagulativo (ATIII, d-Dimeri, Fibrinogeno) e marker d’infiammazione (CRP). Dei pazienti inclusi è stato seguito il follow-up clinico e clinicopatologico per un periodo di tempo di due anni e sono stati considerati. Risultati: Le alterazione clinicopatologiche principali sono state anemia (41%), iperprotidemia (42%), iperglobulinemia (75%), ipoalbuminemia (66%), aumento della CRP (57%), incremento dell’UAC (78%), aumento dell’UPC (70%), peso specifico inadeguato (54%) e riduzione dell’ATIII (52%). Il 37% dei pazienti non era proteinurico e di questi il 27% aveva già un’albuminuria patologica. Il 38% dei pazienti aveva una proteinuria nefrosica (UPC>2,5) e il 22% era iperazotemico. I parametri clinicopatologici hanno mostrato una tendenza a rientrare nella normalità dopo il 90° giorno di follow-up. La creatinina sierica, tramite un analisi multivariata, è risultata essere il parametro correlato maggiormente con l’outcome del paziente. Conclusione: i risultati ottenuti in funzione dell’outcome dei pazienti hanno mostrato che i soggetti deceduti durante il follow-up, al momento dell’ammissione avevano valori di creatinina, UPC e UAC più elevati e ingravescenti. Inoltre l’UAC può venire considerato un marker precoce di nefropatia e la presenza di iperazotemia all’ammissione, in questi pazienti, ha un valore prognostico negativo.

Sleep motor activity in parkinsonian syndromes at onset: a prospective study to determine potential diagnostic and prognostic markers

Aim of this study is to describe the possible diagnostic value of sleep disturbances in the differential diagnosis of neurodegenerative diseases characterized by parkinsonism at onset. 42 consecutive patients with parkinsonian features and disease duration up to 3 years were included in the BO-ProPark study. Each patient was evaluated twice, at baseline (T0) and 16 months later (T1). Patients were diagnosed as Parkinson disease (PD, 27 patients), PD plus (PD with cognitive impairment/dementia or dysautonomia, 4 patients) and parkinsonian syndrome (PS, 11 patients). All patients underwent a full night video-polysomnography scored by a neurologist blinded to the clinical diagnosis. Sleep efficiency and total sleep time were reduced in all patients; wake after sleep onset was higher in patients with atypical parkinsonisms than in PD patients. No significant differences between groups of patients were detected in other sleep parameters. The mean percentage of epochs with enhanced tonic muscle EMG activity during REM sleep was higher in PD plus and PS than in PD. No difference in phasic muscle EMG activity during REM sleep was seen between the two groups. REM behaviour disorder was more frequent in PD plus and PS than in PD patients. Our data suggest that REM sleep motor control is more frequently impaired at disease onset in patients with PS and PD plus compared to PD patients. The presence of RBD or an enhanced tonic muscle EMG activity in a patient with recent onset parkinsonian features should suggest a diagnosis of atypical parkinsonism, rather than PD. More data are needed to establish the diagnostic value of these features in the differential diagnosis of parkinsonisms. The evaluation of sleep disorders may be a useful tool in the differential diagnosis of parkinsonism at onset.