BONHEUR YvesMelanin ni ijambo rituruka mu kigereki risobanura kwirabura cg umukara. Akenshi iyo rivuzwe duhita twumva abirabura, kandi koko niko bimeze kuko uyu musemburo ushinzwe ibara ry’uruhu uba mwinshi ku bafite uruhu rwirabura bakaba banatuye ahaba izuba ryinshi.
Ubwoko bw’ingenzi bwa melanin bubaho ni eumelanin na pheomelanin. Eumelanin (soma: emelanine) ikaba ariyo itanga ibara ry’igitaka n’umukara, mu gihe pheomelanin (soma: fewomelanine) iboneka nk’umutuku n’umuhondo. Iyi misemburo ikorwa n’urusobe rw’uturemangingo tuzwi nka melanocytes.
Ese melanin iboneka mu bantu bose ku rugero rumwe?
Nkuko twabivuze hejuru melanin, iboneka mu bantu bose, gusa si ku rugero rumwe.
Urugero: umuntu wirabura cyane aba afite eumelanin nyinshi, naho uwera cyane akaba afite pheomelanin nyinshi.
Melanocytes (uturemangingo dukora melanin) ntidukora ku rugero rumwe mu bantu bose; iyi niyo mpamvu habaho abirabura, abera n’abasa umuhondo. Mu birabura melanin ntikorwa ku rugero rungana, ariyo mpamvu habaho ibikara n’inzobe, kandi bose birabura.
Abantu bose ntibagira melanin ku rugero rumwe, uko iba nyinshi mu mubiri niko uruhu rwirabura.
Akamaro ka melanin ku mubiri
1. Ni ingenzi ku bwonko n’ibindi bice by’umubiri imbere
Melanin igira akamaro gakomeye mu gutanga ibara ry’uruhu n’umusatsi. Hafi ya buri karemangingo k’umubiri usangamo melanin by’umwihariko ku bwonko n’imyakura ngo bikore neza, ku mboni y’ijisho (iris) kugira ngo tubone neza ndetse no mu turemangingofatizo ngo tubashe kwiyongera.
Iyo umubiri ubuze melanin nibwo habaho nyamweru (albinism)
2. Ifasha gushwanyaguza ibibyara uburozi
Uko umubiri ukora hagenda haboneka ibisigazwa kandi uko byibika muri wo bibyara uburozi bwangiza bimwe mu bice by’umubiri harimo n’uruhu.
Melanin ifasha umubiri kwangiza ibyo byakabyaye uburozi nuko ikarinda ingaruka zari guterwa nabwo cyane cyane ku ruhu.
3. Ifasha kwinjiza vitamin D mu mubiri
Vitamin D ni imwe muri vitamine z’ingenzi cyane, kuko ifasha umubiri kwinjiza Calcium n’indi myunyungugu y’ingenzi yitabazwa mu gukura kw’amagufa no gusana uruhu.
Melanin, umusemburo uboneka ku ruhu ufasha kwinjiza no kuringaniza urugero rw’iyi vitamin mu mubiri. Uretse ibi kandi ifasha kurinda imirasire mibi y’izuba, cyane cyane aho ricana cyane, ishobora gutera kanseri.
Niyo mpamvu uzasanga ku bantu baba hafi y’umurongo ugabanyamo isi 2 (kuri equateur), aho izuba riva cyane baba birabura kurusha abatuye ku mpera z’isi (Mu burayi, pole nord na pole sud).Ku bantu batuye ahatava izuba cg batagera ku zuba, ni ngombwa gufata inyongera za vitamin D cg kurya ibyo ibonekamo cyane
4. Ituma uruhu rudasaza vuba
Kujya ku zuba kenshi byangiza uruhu bigatuma rusaza rukanazana iminkanyari ariko kandi ku bafite uruhu rwirabura siko bigenda kuko biratinda.
Niyo mpamvu uzasanga umuntu munganya imyaka ariko w’uruhu rwera agaragaza gusaza ku ruhu no kuzana iminkanyari kurenza wowe kuko melanin yawe iba yakoze akazi ishinzwe ko kurinda uruhu.
5. Ifasha mu myororokere
Aha wenda wabyumvamo amakabyankuru ariko si ugukabya. Melanin irinda ko DNA yakangirika, igatuma umubiri winjiza UV ikenewe gusa kandi ikarinda kwangirika kwa vitamin B9 (folic acid). Iyi vitamin ni ingenzi ku mugore utwite kuko irinda umwana we kuba yazavukana ubusembwa cyangwa ubumuga.
MU GUSOZA
Si ibi gusa byiza bya melanin ahubwo twaguhitiyemo iby’ingenzi.
Bumwe mu buryo bukoreshwa n’abatuye ahava izuba cyane (cyane cyane muri Afurika) mu guhindura uruhu, bwangiza bikomeye uyu musemburo wa melanin.
Amavuta akoreshwa mu kwitukuza cg gukesha uruhu (cyane cyane abonekamo hydroquinone) yangiza bikomeye melanin, bityo uruhu rukangirika mu buryo bworoshye.
