You can grow new brain cells. Here's how | Sandrine Thuret | TED

Translator: Socorro Rodríguez Holguín Reviewer: Enara Caride

É posible que os adultos fagamos que nos medren novas neuronas?

Can we, as adults, grow new nerve cells?

Aínda hai certa incertidume sobre este asunto,

There's still some confusion about that question,

as this is a fairly new field of research.

en tanto que é unha área de investigación moi novidosa.

For example, I was talking to one of my colleagues, Robert,

Por exemplo, falando cun colega meu, Robert,

who is an oncologist,

un oncólogo,

and he was telling me,

comentábame,

"Sandrine, isto é desconcertante.

"Sandrine, this is puzzling.

Some of my patients that have been told they are cured of their cancer

Algúns pacientes meus, logo de saber que están curados dun cancro

aínda desenvolven síntomas de depresión".

still develop symptoms of depression."

And I responded to him,

E eu respondinlle,

"Well, from my point of view that makes sense.

"Ben, na miña opinión iso ten lóxica.

The drug you give to your patients that stops the cancer cells multiplying

A droga que lle dás, que frea a proliferación das células cancerosas

also stops the newborn neurons being generated in their brain."

tamén frea o nacemento de neuronas no cerebro.

And then Robert looked at me like I was crazy and said,

E Robert quedou a mirar para min como se eu tolease e dixo,

"But Sandrine, these are adult patients --

"Pero Sandrine, son pacientes adultos,

adults do not grow new nerve cells."

aos adultos non nos medran neuronas novas."

And much to his surprise, I said, "Well actually, we do."

E, para as súa sorpresa, díxenlle, "Medránnos, si".

E isto é o que chamamos neuroxénese.

And this is a phenomenon that we call neurogenesis.

[Neurogenesis]

[Neuroxénese]

Pero Robert non é neurocientífico;

Now Robert is not a neuroscientist,

and when he went to medical school he was not taught what we know now --

e cando el estudaba Medicina non se ensinaba o que sabemos agora:

that the adult brain can generate new nerve cells.

que o cerebro adulto pode xerar novas células nerviosas.

So Robert, you know, being the good doctor that he is,

Así que Robert, como bo científico que é

wanted to come to my lab

quixo vir ao meu laboratorio

to understand the topic a little bit better.

para entender isto un pouco mellor.

And I took him for a tour

E leveino nunha visita guiada

a unha das partes máis excitantes do cerebro

of one of the most exciting parts of the brain

no que a neuroxénese se refire:

when it comes to neurogenesis --

and this is the hippocampus.

ao hipocampo.

Esta estrutura gris no centro do cerebro.

So this is this gray structure in the center of the brain.

And what we've known already for very long,

E da que sabemos hai tempo

que é importante para a aprendizaxe, a memoria, o estado de ánimo e a emoción.

is that this is important for learning, memory, mood and emotion.

However, what we have learned more recently

Sen embargo, o que sabemos só desde hai pouco

is that this is one of the unique structures of the adult brain

é que é unha das únicas estruturas do cerebro adulto

onde se poden xerar novas neuronas.

where new neurons can be generated.

And if we slice through the hippocampus

Se seccionamos o hipocampo

and zoom in,

e miramos nel con aumento,

o que poden ver aqui en azul

what you actually see here in blue

is a newborn neuron in an adult mouse brain.

é unha neurona recén nacida nun cerebro de rato adulto.

So when it comes to the human brain --

No caso do cerebro humano,

my colleague Jonas Frisén from the Karolinska Institutet,

o meu colega Jonas Frisén do Instituto Karolinska,

has estimated that we produce 700 new neurons per day

ten estimado que producimos 700 neuronas novas ao día

no hipocampo.

in the hippocampus.

You might think this is not much,

Poden pensar que non son moitas,

compared to the billions of neurons we have.

comparadas cos miles de millóns de neuronas que temos.

But by the time we turn 50,

Pero aos cincuenta anos,

we will have all exchanged the neurons we were born with in that structure

teremos renovado todas as neuronas desta estrutura coas que nacimos

with adult-born neurons.

con neuronas nacidas sendo adultos.

So why are these new neurons important and what are their functions?

Entón, por que son importantes estas novas neuronas e que funcións cumpren?

First, we know that they're important for learning and memory.

Primeiro, sabemos que son importantes para a aprendizaxe e a memoria.

E no laboratorio temos amosado

And in the lab we have shown

that if we block the ability of the adult brain

que se bloqueamos a capacidade do cerebro adulto

to produce new neurons in the hippocampus,

para producir novas neuronas no hipocampo,

then we block certain memory abilities.

bloquéanse certas capacidades de memoria.

And this is especially new and true for spatial recognition --

E isto é especialmente novidoso e certo no caso do recoñecemento espacial,

so like, how you navigate your way in the city.

ou sexa, como recorremos o noso camiño pola cidade.

We are still learning a lot,

Aínda estamos a aprender moito,

and neurons are not only important for memory capacity,

e as neuronas son importantes non só para a capacidade de memoria,

but also for the quality of the memory.

senón tamén para a súa calidade.

And they will have been helpful to add time to our memory

E son de axuda para engadir tempo á nosa memoria

and they will help differentiate very similar memories, like:

e tamén para diferenciar entre memorias moi parecidas, a saber:

how do you find your bike

como atopas a túa bicicleta

that you park at the station every day in the same area,

que aparcas na estación todos os días na mesma zona,

pero en lugares lixeiramente distintos?

but in a slightly different position?

E o que é máis interesante para o meu colega Robert

And more interesting to my colleague Robert

is the research we have been doing on neurogenesis and depression.

é a investigación que estamos a facer sobre neuroxénese e depresión.

Así, nun modelo animal da depresión,

So in an animal model of depression,

we have seen that we have a lower level of neurogenesis.

temos atopado que se dá un baixo nivel de neuroxénese.

And if we give antidepressants,

E cando administramos antidepresivos,

then we increase the production of these newborn neurons,

auméntase a produción destas novas neuronas,

and we decrease the symptoms of depression,

e diminúen os síntomas de depresión

establishing a clear link between neurogenesis and depression.

o que establece unha relación clara entre neuroxénese e depresión.

But moreover, if you just block neurogenesis,

Pero ademais, bloqueando só a neuroxénese,

then you block the efficacy of the antidepressant.

bloquéase a eficacia do antidepresivo.

So by then, Robert had understood

Así que para entón, Robert entendera

that very likely his patients were suffering from depression

que probablemente os seus pacientes sufrían de depresión

even after being cured of their cancer,

despois de curarse do cancro,

because the cancer drug had stopped newborn neurons from being generated.

porque o anticanceríxeno detivera a xeneración de novas neuronas.

And it will take time to generate new neurons

E precísase un tempo para xerar novas neuronas

that reach normal functions.

que acaden as súas funcións normais.

So, collectively, now we think we have enough evidence

Así, en conxunto, pensamos que temos evidencia de abondo

to say that neurogenesis is a target of choice

para afirmar que a neuroxénese é unha clara alternativa

if we want to improve memory formation or mood,

se queremos mellorar a formación de memorias e o estado anímico,

or even prevent the decline associated with aging,

ou mesmo previr o declive asociado ao avellentamento,

ou asociado ao estrés.

or associated with stress.

So the next question is:

Xa que logo, a seguinte pregunta é:

podemos controlar a neuroxénese?

can we control neurogenesis?

A resposta é si.

The answer is yes.

And we are now going to do a little quiz.

E agora imos facer unha pequena proba.

I'm going to give you a set of behaviors and activities,

Voulles indicar unha serie de condutas e actividades,

and you tell me if you think they will increase neurogenesis

e vanme dicir se pensan que aumentan a neuroxénese

ou que a diminúen.

or if they will decrease neurogenesis.

Are we ready?

Listos?

OK, let's go.

OK, imos aló.

Que opinan da aprendizaxe?

So what about learning?

Increasing?

Auméntaa?

Yes.

Si.

Learning will increase the production of these new neurons.

Aprender aumentará a produción destas novas neuronas.

How about stress?

E o estrés?

Yes, stress will decrease the production of new neurons in the hippocampus.

Si, o estrés diminúe a produción de novas neuronas no hipocampo.

How about sleep deprivation?

Que hai da privación de sono?

Indeed, it will decrease neurogenesis.

Efectivamente, diminúe a neuroxénese.

E o sexo?

How about sex?

Oh, wow!

Oh, vaia!

(Laughter)

(Risos)

Yes, you are right, it will increase the production of new neurons.

Si, acertaron, aumenta a produción de novas neuronas.

However, it's all about balance here.

Non obstante, aquí hai que buscar o equilibrio.

We don't want to fall in a situation --

Non queremos chegar a unha situación,

(Risos)

(Laughter)

na que demasiado sexo leve á privaciónd de sono.

about too much sex leading to sleep deprivation.

(Laughter)

(Risos)

How about getting older?

E que din de facerse vello?

So the neurogenesis rate will decrease as we get older,

A taxa de neuroxénese diminúe ao facerse vello,

but it is still occurring.

pero aínda ocorre.

E xa para rematar, que din de correr?

And then finally, how about running?

I will let you judge that one by yourself.

Vou deixar que xulguen por si mesmos.

So this is one of the first studies

Este é un dos primeiros estudos

that was carried out by one of my mentors, Rusty Gage from the Salk Institute,

levados a cabo polo un dos meus mentores, Rusty Gage, do Instituto Salk,

showing that the environment can have an impact

que amosa que o ambiente pode ter un impacto

na produción de novas neuronas.

on the production of new neurons.

Aquí poden ver unha sección do hipocampo dun rato

And here you see a section of the hippocampus of a mouse

that had no running wheel in its cage.

que non tiña roda de exercicio na súa gaiola.

And the little black dots you see are actually newborn neurons-to-be.

Os pequenos puntos negros que ven son novas neuronas formándose.

And now, you see a section of the hippocampus of a mouse

E agora, poden ver a sección do hipocampo dun rato

that had a running wheel in its cage.

con roda de exercicio na gaiola.

Poden ver o incremento masivo

So you see the massive increase

of the black dots representing the new neurons-to-be.

de puntos negros que representan novas neuronas en formación.

So activity impacts neurogenesis, but that's not all.

Así que a actividade inflúe na neuroxénese pero isto non é todo.

What you eat will have an effect

O que comemos tamén ten efecto

on the production of new neurons in the hippocampus.

na produción de novas neuronas no hipocampo.

So here we have a sample of diet --

Aquí temos a mostra dunha dieta,

of nutrients that have been shown to have efficacy.

de nutrintes que se teñen demostrado eficaces.

And I'm just going to point a few out to you:

E voulles sinalar algúns:

Calorie restriction of 20 to 30 percent will increase neurogenesis.

Unha restrición calórica do 20 ao 30 por cento aumenta a neuroxénese.

O xaxún intermitente -- espaciar o tempo entre comidas --

Intermittent fasting -- spacing the time between your meals --

will increase neurogenesis.

aumenta a neuroxénese.

Intake of flavonoids,

A inxesta de flavonoides,

que se atopan no chocolate negro ou nas arandeiras,

which are contained in dark chocolate or blueberries,

aumenta a neuroxénese.

will increase neurogenesis.

Omega-3 fatty acids,

Os ácidos graxos Omega-3,

present in fatty fish, like salmon,

presentes en peixes graxos, como o salmón,

aumentan a produción desas novas neuronas.

will increase the production of these new neurons.

Conversely, a diet rich in high saturated fat

Pola contra, unha dieta rica en graxas saturadas

will have a negative impact on neurogenesis.

ten un impacto negativo na neuroxénese.

Ethanol -- intake of alcohol -- will decrease neurogenesis.

O etanol -- a inxesta de alcohol -- diminúe a neuroxénese.

However, not everything is lost;

Sen embargo, non todo está perdido;

resveratrol, which is contained in red wine,

o resveratrol, que se atopa no viño,

has been shown to promote the survival of these new neurons.

tense demostrado que promove a supervivencia destas novas neuronas.

So next time you are at a dinner party,

Así que a próxima vez que vaian de cea,

you might want to reach for this possibly "neurogenesis-neutral" drink.

poden procurar acadar ese punto de bebida 'neutral' para a neuroxénese.

(Laughter)

(Risos)

E, para rematar, deixen que apunte unha última cousa,

And then finally, let me point out the last one --

a quirky one.

unha un tanto curiosa.

So Japanese groups are fascinated with food textures,

Aos xaponeses fascínalle as texturas das comidas,

and they have shown that actually soft diet impairs neurogenesis,

e tense demostrado que as dietas blandas prexudican á neuroxénese,

a diferenza da comida que require masticar, ou os alimentos crocantes.

as opposed to food that requires mastication -- chewing -- or crunchy food.

So all of this data,

Todos estes datos,

where we need to look at the cellular level,

para os que temos que mirar a nivel celular,

has been generated using animal models.

conseguíronse usando modelos animais.

But this diet has also been given to human participants,

Pero esta dieta tamén se ten administrado a humanos,

and what we could see is that the diet modulates memory and mood

e o que puidemos ver é que a dieta modula a memoria e o estado de ánimo

na mesma dirección que modula a neuroxénese,

in the same direction as it modulates neurogenesis,

such as: calorie restriction will improve memory capacity,

isto é: a restrición calórica mellora a capacidade de memoria,

whereas a high-fat diet will exacerbate symptoms of depression --

mentres que unha dieta alta en graxas exacerba os síntomas da depresión,

as opposed to omega-3 fatty acids, which increase neurogenesis,

ao contrario que os ácidos graxos Omega-3, que incrementan a neuroxénese,

and also help to decrease the symptoms of depression.

e tamén axudan a diminuír os síntomas depresivos.

So we think that the effect of diet

Así que nós pensamos que o efecto da dieta

on mental health, on memory and mood,

na saúde mental, a memoria e o estado de ánimo,

está realmente mediado pola produción de novas neuronas no hipocampo.

is actually mediated by the production of the new neurons in the hippocampus.

And it's not only what you eat,

E non é só o que comemos,

but it's also the texture of the food, when you eat it

tamén é a textura dos alimentos, cándo os comes

e a cantidade deles que inxires.

and how much of it you eat.

On our side -- neuroscientists interested in neurogenesis --

Pola nosa banda -- os neurocientíficos interesados na neuroxénese --

we need to understand better the function of these new neurons,

precisamos entender mellor a función destas novas neuronas,

and how we can control their survival and their production.

e como poder controlar a súa supervivencia e a súa produción.

We also need to find a way to protect the neurogenesis of Robert's patients.

Tamén temos que atopar a forma de protexer a neuroxénese dos pacientes de Robert.

And on your side --

E pola súa banda,

I leave you in charge of your neurogenesis.

déixoos a cargo da súa propia neuroxénese.

Thank you.

Grazas.

(Applause)

(Aplausos)

Margaret Heffernan: Fantastic research, Sandrine.

Margaret Heffernan: Estupenda investigación, Sandrine.

Now, I told you you changed my life --

Teño que dicirche que vés de cambiame a vida.

I now eat a lot of blueberries.

Vou comer un montón de arandeiras.

Sandrine Thuret: Very good.

Sandrine Thuret: Moi ben.

MH: I'm really interested in the running thing.

MH: Interésame moito o de correr.

Do I have to run?

Teño que correr?

Or is it really just about aerobic exercise,

Ou vale calquera exercicio aeróbico,

que leve osíxeno ao cerebro?

getting oxygen to the brain?

Could it be any kind of vigorous exercise?

Sirve calquera clase de exercicio intenso?

ST: Polo de agora,

ST: So for the moment,

we can't really say if it's just the running itself,

non podemos dicir con seguridade se é correr en sí,

pero penso que calquera cousa que aumente a produción

but we think that anything that indeed will increase the production --

or moving the blood flow to the brain,

ou o fluxo de sangue ao cerebro,

should be beneficial.

debería ser beneficiosa.

MH: Entón non teño que ter unha roda de exercicio na oficina?

MH: So I don't have to get a running wheel in my office?

ST: Non, non fai falla!

ST: No, you don't!

MH: Oh, what a relief! That's wonderful.

MH: Uf, que alivio! É marabilloso.

Sandrine Thuret, thank you so much.

Sandrine Thuret, moitas grazas.

ST: Grazas a ti, Margaret.

ST: Thank you, Margaret.

(Applause)

(Aplausos)