Why do some people go bald? - Sarthak Sinha

Zašto neki ljudi ćelave? - Sartak Sinha (Sarthak Sinha)

Prevodilac: Mile Živković Lektor: Milenka Okuka

What do Charles Darwin, Michael Jordan, and Yoda have in common?

Šta imaju zajedničko Čarls Darvin, Majkl Džordan i Joda?

They, like many other historical and fictive individuals, are bald,

Poput mnogih drugih istorijskih i stvarnih ličnosti, oni su ćelavi,

in some cases by their own choice.

u nekim slučajevima je to lični izbor.

For centuries, a shining dome has been a symbol of intelligence,

Glava koja se presijava, vekovima je bila simbol inteligencije,

but despite this, many balding people still wish their hair would return.

ali uprkos ovome, mnogi ćelavi ljudi bi ipak želeli da im se vrati kosa.

Scientists have long pondered,

Naučnici su se dugo pitali,

"Why do some people lose their hair, and how can we bring it back?"

zašto neki ljudi gube kosu i kako se ona može vratiti.

The full-headed among us have about 100,000 to 150,000 hairs on our scalps,

Oni među nama sa punom grivom imaju oko 100 000 do 150 0000 dlaka na glavi

and scientists have discovered two things about this dense thicket.

i naučnici su otkrili dve stvari u vezi sa ovim gustim šipražjem.

Firstly, the sprouting hair we see is mostly made up of keratin,

Prvo, kosa koja niče i koju vidimo većinom se sastoji od keratina,

the protein leftover from dead cells that are forced upwards

proteina koji ostaje od mrtvih ćelija koje se guraju nagore

as new cells grow beneath them.

dok nove ćelije rastu pod njima.

Secondly, the structures that drive hair growth

Drugo, strukture koje vode rast dlake

are called hair follicles,

nazivaju se folikulima kose

a network of complex organs that forms before we're born,

i predstavljaju mrežu složenih organa koji se formiraju pre našeg rođenja

and grows hair in an everlasting cycle.

i uz koje kosa raste u neprekidnom ciklusu.

This cycle has three main phases.

Ovaj ciklus ima tri glavne faze.

The first is anagen, the growth phase,

Prva je anagen, faza rasta,

which up to 90% of your hair follicles are experiencing right now,

kroz koju trenutno prolazi do 90% vaših folikula kose

causing them to push up hair at a rate of one centimeter per month.

i od koje kosa raste nagore brzinom od jednog centimetra mesečno.

Anagen can last for two to seven years, depending on your genes.

Anagen može trajati od dve do sedam godina u zavisnosti od vaših gena.

After this productive period,

Nakon ovog produktivnog perioda,

signals within the skin instruct some follicles to enter a new phase

signali unutar kože navode neke folikule na početak nove faze

known as catagen, or the regressing stage,

koja se zove katagen, ili faza regresije,

causing hair follicles to shrink to a fraction of their original length.

pri čemu se folikuli kose skupljaju na mali deo svoje prvobitne veličine.

Catagen lasts for about two to three weeks

Katagen traje oko dve do tri nedelje

and cuts blood supply to the follicle, creating a club hair,

i prekida dovod krvi do folikula, stvarajući mrtvu dlaku

meaning it's ready to be shed.

koja je spremna da opadne.

Finally, hairs enter telogen, the resting phase,

Konačno, dlaka ulazi u telogen, ili fazu odmaranja,

which lasts for ten to twelve weeks,

koja traje od deset do dvanaest nedelja

and affects about 5-15% of your scalp follicles.

i pogađa oko 5 do 15% vaših folikula kože glave.

During telogen, up to 200 club hairs can be shed in a day,

Tokom telogena, i do 200 mrtvih dlaka može da opadne za jedan dan,

which is quite normal.

što je prilično normalno.

Then, the growth cycle begins anew.

Ciklus rasta onda počinje iznova.

But not all heads are hairy,

Ali nisu sve glave dlakave,

and, in fact, some of them grow increasingly patchy over time

i neke od njih zapravo postaju sve više proćelave tokom vremena

in response to bodily changes.

kao odgovor na promene u telu.

95% of baldness in men can be attributed to male pattern baldness.

95% ćelavosti kod muškaraca može se pripisati muškom tipu ćelavosti.

Baldness is inherited,

Ćelavost je nasledna,

and in people with this condition,

i kod ljudi sa ovom boljkom,

follicles become incredibly sensitive to the effects of dihydrotestosterone,

folikuli postaju izuzetno osetljivi na efekte dihidrotestosterona,

a hormonal product made from testosterone.

hormonskog proizvoda koji nastaje od testosterona.

DHT causes shrinkage in these overly sensitive follicles,

DHT izaziva smanjivanje kod ovih preosetljivih folikula,

making hair shorter and wispier.

od čega kosa postaje kraća i pramenastija.

But loss isn't sudden.

Ali gubitak nije iznenadan.

It happens gradually, along a metric known as the Norwood Scale,

Dešava se postepeno, po šablonu poznatom kao Norvudova skala,

which describes the severity of hair loss.

koja opisuje ozbiljnost gubitka kose.

First, hair recedes along the temples,

Kosa se prvo povlači kod slepoočnica,

then hair on the crown begins to thin in a circular pattern.

a onda počinje da se proređuje kosa na temenu u kružnoj putanji.

At the highest rating on the scale,

Na najvišem stupnju skale,

these balding areas meet and expand dramatically,

ove površine koje ćelave susreću se i dramatično šire,

eventually leaving only a ring of sparse hair around the temples

ostavljajući na kraju samo prsten retke kose oko slepoočnica

and the back of the head.

i na zadnjem delu glave.

Genetics isn't all that drives hair loss.

Genetika nije jedina odgovorna za ćelavost.

Long periods of stress can release signals that shock follicles

Dugi periodi stresa mogu da pošalju signale koji šokiraju folikule

and force them into the resting phase prematurely.

i nateraju ih da pre vremena stupe u fazu odmaranja.

Some women experience this after childbirth.

Neke žene ovo doživljavaju nakon porođaja.

Follicles might also lose the ability to go into anagen, the growth phase.

Folikuli takođe mogu izgubiti sposobnost da stupe u fazu rasta, anagen.

People going through chemotherapy treatment temporarily experience this.

Ovo se privremeno događa ljudima koji prolaze kroz hemoterapiju.

But while balding may look permanent,

Ali iako ćelavost izgleda trajna,

scientific investigation has revealed the opposite.

naučna istraživanja su otkrila da je situacija suprotna.

Below the skin's surface,

Ispod površine kože,

the roots that give rise to our hair actually remain alive.

koreni iz kojih naša kosa raste zapravo ostaju živi.

Using this knowledge,

Koristeći ovo znanje,

scientists have developed drugs that shorten the resting phase,

naučnici su razvili lekove koji skraćuju fazu odmora

and force follicles into anagen.

i folikule teraju u anagen.

Other drugs combat male pattern baldness

Drugi lekovi se bore protiv muškog tipa ćelavosti

by blocking the conversion of testosterone to DHT

tako što blokiraju prelaz iz testosterona u DHT

so that it doesn't affect those sensitive follicles.

tako da on ne pogađa te osetljive folikule.

Stem cells also play a role in regulating the growth cycle,

Stem ćelije takođe igraju ulogu u upravljanju ciklusom rasta

and so scientists are investigating whether they can manipulate

i naučnici istražuju da li uz pomoć njih mogu da manipulišu

the activity of these cells to encourage follicles to start producing hair again.

aktivnošću ovih ćelija kako bi podstakli folikule da ponovo proizvode kosu.

And in the meantime,

U međuvremenu,

while scientists hone their hair-reviving methods,

dok naučnici usavršavaju metode za vraćanje kose u život,

anyone going bald, or considering baldness,

svako ko ćelavi ili razmatra tu mogućnost

can remember that they're in great company.

može da se seti da je u sjajnom društvu.