Parkinson's disease (PD) is a chronic neurodegenerative disorder that affects the brain areas controlling the coordination of movements and balance. Patients also have different nonmotor symptoms such as loss of smell, cognitive impairment or rapid-eye-movement (REM) sleep behavior disorder (RBD), which may appear years before the onset of the disease. These symptoms are caused by the accumulation of the protein alpha-synuclein in neurons in the Lewy bodies, protein clumps that are the pathological hallmark of Parkinson’s disease. Detecting the presence of this protein in an early stage of PD would be useful to diagnose the disease before its onset and start treating the symptoms from the beginning.
In the study published in The Lancet Neurology journal, researchers evaluated whether a biopsy in the submandibular gland can detect aggregates of alpha-synuclein. These biopsies were performed in 21 patients with RBD, in 24 with Parkinson's disease and 26 healthy people. In about 90% of patients with sleep disorders and 70% of those with Parkinson the protein was detected by a submandibular gland biopsy, while it was not found in any of the healthy people. "These results show that the biopsy is useful as a confirmatory test to diagnose PD in those people whose disease has not begun," explains Dr. Alex Iranzo, neurologist at the Sleep Disorders Multidisciplinary Unit of the Hospital Clinic and researcher at the IDIBAPS Neurophysiology and functional studies of the nervous system team. "In addition, it is a minimally invasive and a well tolerated test," he adds.
"Identifying synuclein aggregates in the submandibular gland can confirm the diagnosis of Parkinson, very useful in cases of uncertain diagnosis. Also, identifying people with sleep disorders that have these aggregates could be helpful, for example, to design therapeutic strategies to block the progression of this protein to the central nervous system, where they cause the classic symptoms of Parkinson's disease," explains Dr. Eduard Tolosa.
Dolores Vilas†, Alex Iranzo, MD†, Prof Eduardo Tolosa, Iban Aldecoa†, Joan Berenguer, Isabel Vilaseca, Carles Martí, Mónica Serradell, Francisco Lomeña, Llucia Alós, Carles Gaig, Joan Santamaria, Ellen Gelpi
Published Online: 30 March 2016 DOI: http://dx.doi.org/10.1016/S1474-4422(16)00080-6
Ugonjwa wa Parkinson ni ugonjwa wa neurodegenerative ambao huathiri sehemu za ubongo zinazodhibiti uratibu wa harakati na usawa. Wagonjwa pia wana dalili tofauti za nonmotor, kama vile kupoteza harufu, kupungua kwa utambuzi, au ugonjwa wa tabia ya usingizi wa harakati ya haraka ya jicho (REM), ambayo inaweza kuonekana miaka kabla ya kuanza kwa ugonjwa. Matatizo haya hutokana na mkusanyiko wa protini ya alpha-synuclein katika neuroni katika miili ya Lewy, makundi ya protini ambayo ni alama ya ugonjwa wa Parkinson. Kugundua uwepo wa protini hii katika hatua ya mapema ya ugonjwa wa Parkinson itakuwa muhimu kugundua ugonjwa kabla ya kuanza kwake na kuanza kutibu dalili kutoka mwanzo. Katika utafiti uliochapishwa katika jarida la The Lancet Neurology, watafiti walichunguza ikiwa upasuaji wa viungo vya chini ya kidonda cha mandibular unaweza kugundua jumla ya alpha-synuclein. Biopsy hizo zilifanywa kwa wagonjwa 21 wenye RBD, 24 wenye ugonjwa wa Parkinson na 26 wenye afya. Katika asilimia 90 ya wagonjwa wenye matatizo ya usingizi na asilimia 70 ya wagonjwa wenye ugonjwa wa Parkinson, protini hiyo iligunduliwa kwa kutumia uchunguzi wa kibofu cha chini ya kidole, wakati haikugunduliwa kwa watu wenye afya. "Hii ni matokeo ya utafiti wa utafiti wa ubongo wa binadamu, ambao unaonyesha kuwa ni muhimu kwa wagonjwa ambao bado hawajaanza ugonjwa wa Parkinson, ""alisema Dk Alex Iranzo, mtaalamu wa neva katika kitengo cha Sleep Disorders Multidisciplinary Unit cha Kliniki ya Hospitali na mtafiti katika timu ya IDIBAPS ya Neurophysiology na Functional Studies ya mfumo wa neva." "Zaidi ya hayo, ni mtihani usio na madhara makubwa na unaovumiliwa vizuri", aongezea. "Kutambua synuclein aggregates katika gland submandibular inaweza kuthibitisha utambuzi wa Parkinson, muhimu sana katika kesi ya utambuzi usio na uhakika. "Kujulikana kwa watu wenye matatizo ya usingizi ambayo yana viungo hivi inaweza kusaidia, kwa mfano, kubuni mikakati ya matibabu ya kuzuia maendeleo ya protini hii kwenye mfumo wa neva wa kati, ambapo husababisha dalili za kawaida za ugonjwa wa Parkinson. """ "Mwanamke huyo, ambaye pia ni mwanasayansi wa utafiti wa afya, anaitwa ""Dolores Villas,"" na anaongozwa na Iván Aldecoa, ""Joain Berenguer,"" ""Isabel Villaseca,"" ""Carles Martí,"" ""Mónica Serradell,"" ""Francisco Lomeña,"" ""Lucia Alves,"" ""Carles Gaig,"" ""Joain Santamaria,"" na ""Ellen Gelpi."""