Unusual strobing light and sound treatment reverses Alzheimer's in mice
Could an hour's exposure every day to a specifically calibrated flickering light and droning sound help clear your brain of the toxic proteins that cause Alzheimer's disease? An intriguing new MIT study raises this possibility after successful mouse experiments showed marked neurological improvements through simple visual and auditory stimulation.
Back in 2016 Li-Huei Tsai and colleagues at MIT's Picower Institute for Learning and Memory were investigating the correlation between impaired gamma oscillations in the brain and Alzheimer's disease. These gamma oscillations can range anywhere from 25 to 100 Hertz, but there has long been a hypothesis that 40 Hz is the magic frequency for optimal brain functioning.
Using optogenetic technology the researchers specifically stimulated individual neurons in an animal's hippocampus, discovering dramatic reductions in both amyloid and tau proteins after just one hour of stimulation at 40 Hz. Fascinatingly, the researchers then discovered similar effects could be generated in the mouse brain through simple external exposure to a light flickering at 40 Hz.
In a newly published study the MIT team explored the effects of adding sound stimuli to the treatment. The results reveal similar effects, with an hour's exposure to 40 Hz tones per day significantly reducing amyloid build-up in both the auditory cortex and hippocampus of mouse brains.
"What we have demonstrated here is that we can use a totally different sensory modality to induce gamma oscillations in the brain," says Tsai. "And secondly, this auditory-stimulation-induced gamma can reduce amyloid and tau pathology in not just the sensory cortex but also in the hippocampus. When we combine visual and auditory stimulation for a week, we see the engagement of the prefrontal cortex and a very dramatic reduction of amyloid."
The dual visual and auditory treatment proved much more effective than each stimulation by itself. The broader neurological effects of this combined treatment demonstrated enhanced microglia activity in the prefrontal cortex. This suggests the body's innate immune response was heightened by the external stimulation.
The exciting results are not without significant limitations. A large amount of the beneficial effects from the stimulation treatment noticeably faded one week after the treatments had been stopped, meaning there may not be any long-term benefits from the stimulation. It is also unclear exactly why 40 Hz is the perfect frequency to generate these effects, so further study is needed to uncover the molecular mechanisms behind this particular phenomenon.
Underlying all these limitations is of course the fact that the research so far has only been established in mouse models. The entire field of Alzheimer's research is filled with studies that proved promising in animal models, yet could never be replicated in humans.
The research team has already conducted safety tests in humans for the combined visual and auditory treatment, with enrollments underway for a larger trial targeting early-stage Alzheimer's patients. It conceivably will take years to ascertain how effective this technique is in slowing, or reversing, Alzheimer's symptoms in humans, but it is undeniably a fascinating hypothetical treatment.
The new study was published in the journal Cell.
"Uchunguzi wa ""stroboscopic"" wa sauti na mwanga wa kawaida unageuza ugonjwa wa Alzheimer kwa panya: Je, saa moja ya kila siku ya mwangaza wa kila siku na sauti ya sauti inaweza kusaidia kuondoa protini za sumu zinazosababisha ugonjwa wa Alzheimer?" Utafiti mpya wa MIT unaonyesha uwezekano huu baada ya majaribio ya mafanikio ya panya kuonyesha maboresho ya neva kupitia uchochezi rahisi wa kuona na kusikia. Li Hui-Tsai na wenzake katika Taasisi ya Picower ya MIT ya Kujifunza na Kumbukumbu walikuwa wakichunguza uhusiano kati ya kutofaulu kwa oscillations za gamma katika ubongo na ugonjwa wa Alzheimer. "Gamma oscillations inaweza kuenea kutoka 25 hadi 100 Hz, lakini kwa muda mrefu imekuwa nadharia kwamba 40 Hz ni ""majabu"" mzunguko kwa ajili ya utendaji bora wa ubongo." Kwa kutumia teknolojia ya optogenetic, watafiti walichochea neuroni za kipekee katika hippocampus ya mnyama, wakigundua kupunguzwa kwa amyloid na protini za tau baada ya saa moja tu ya kuchochea kwa 40 Hz. Watafiti walipata athari kama hizo katika ubongo wa panya kupitia mfiduo wa nje kwa mwanga wa 40 Hz. Katika utafiti wa hivi karibuni uliochapishwa, timu ya MIT ilichunguza athari za kuongeza vichocheo vya sauti kwa matibabu. Matokeo ya utafiti huo yanaonyesha athari kama hizo, na saa moja ya kuambukizwa kwa sauti za 40 Hz kwa siku hupunguza kwa kiasi kikubwa amyloid katika cortex ya kusikia na hippocampus ya ubongo wa panya. "Kile tumeonyesha hapa ni kwamba tunaweza kutumia njia tofauti kabisa ya hisia kuchochea oscillations gamma katika ubongo", anasema Tsai. "Na kwa pili, gamma hii inayosababishwa na kuchochea kusikia inaweza kupunguza ugonjwa wa amyloid na tau sio tu katika cortex ya hisia lakini pia katika hippocampus. """ "Wakati tunashirikiana stimulation ya kuona na kusikia kwa wiki moja, tunaona ushiriki wa prefrontal cortex na kupunguzwa sana kwa amyloid. """ Matibabu ya kuona na kusikia yalithibitika kuwa yenye matokeo zaidi kuliko kila kichocheo kikiwa peke yake. Athari kubwa za neva za matibabu haya ya pamoja zilionyesha utendaji wa microglia ulioimarishwa katika cortex ya mbele. Hii inaonyesha kwamba mwitikio wa kinga wa mwili uliongezeka kwa sababu ya kichocheo cha nje. Matokeo hayo yenye kusisimua yana mipaka mingi. Matokeo mazuri ya matibabu ya kuchochea yalionekana kufifia wiki moja baada ya matibabu kusimamishwa, ikimaanisha kuwa kunaweza kuwa na faida yoyote ya muda mrefu kutoka kwa kuchochea. Kwa hiyo, haijulikani kwa nini 40Hz ni frequency kamili ya kuzalisha athari hizi, hivyo utafiti zaidi inahitajika kufunua utaratibu wa molekuli nyuma ya jambo hili maalum. Chini ya mapungufu haya yote ni ukweli kwamba utafiti hadi sasa umeanzishwa tu katika mifano ya panya. Utafiti wa Alzheimer's umeonyesha kuwa utafiti huo unaonyesha matokeo mazuri katika mifano ya wanyama, lakini haukuweza kuiga kwa wanadamu. Timu ya utafiti tayari imefanya majaribio ya usalama kwa wanadamu kwa matibabu ya pamoja ya kuona na kusikia, na uandikishaji unaendelea kwa jaribio kubwa linalolenga wagonjwa wa Alzheimer's katika hatua ya mapema. "Inawezekana itachukua miaka kadhaa kugundua jinsi mbinu hii inavyofanya kazi katika kupunguza au kubadilisha dalili za Alzheimer kwa wanadamu, lakini bila shaka ni matibabu ya ""wazo"" ya kuvutia." Utafiti huo mpya ulichapishwa katika jarida la Cell.