An investigation into kojic acid-associated mitochondrial toxicity and inflammation in melanoma cells (SK-MEL-1) = Uphenyo ku-esidi yekojiki ehlobaniswa nokukhinyabezeka kwemayithokhondriya nokuvuvukala ezinhlayiyeni zemelanoma (SK-MEL-1).

Abstract

ojic acid (KA), 5-hydroxy-2-(hydroxymethyl)-4H-pyran-4-one, is used in agriculture, food, and cosmetics. KA is known to have antimicrobial, antifungal, antioxidant, and anti-inflammatory properties. The cosmetic industry's increasing interest in KA is due to its ability to inhibit tyrosinase activity resulting in skin lightening. The mitochondria play a key role in maintaining homeostasis and ensuring efficient melanin production. Therefore, mitochondrial dysfunction has severe effects on the skin. This study investigates mitochondrial stress, antioxidant responses, protein kinase signalling and inflammation in human melanoma (SK-MEL-1) cells. The mitochondria are important in processing metabolites and supplying the cell with energy in the form of ATP. KA interacts with key mitochondrial homeostasis proteins. Our results found an increase in macromolecule damage specifically lipid peroxidation and protein oxidation. Due to oxidative conditions, increased Nrf2 expression was observed. LON protease is ATP-dependent and regulated by Sirtuin 3 expression. Mitochondrial function was affected illustrated by decreased ATP production leading to decreased LON protease and Sirtuin 3 protein expression. Following increased oxidative stress, KA suppressed the expression of protein kinases but increased inflammatory mediators. There was decreased expression of phospho-Akt, Akt, phospho-GSK3β, p38 and ERK1/2. The mediation of the NLRP3 inflammasome involves priming and activation. At concentrations with high proliferation, NFκB gene and protein expression was activated. The protein kinase signalling pathways are known as mediators of inflammation; however, protein and gene expression of inflammatory mediators was increased following KA treatment. The inflammasome was subsequently activated as shown by an increase in intracellular caspase 1 levels as well as NLRP3, ILβ and IL-6 expression. KA induced mitochondrial stress and suppressed mitochondrial homeostasis proteins. The increased Nrf2 expression could have further downregulated LON protease expression and increased macromolecule damage. Oxidative conditions could have activated the inflammasome pathway independent of protein kinase signalling. In conclusion, KA displayed mitochondrial toxicity following acute exposure by suppressing mitochondrial homeostasis, protein kinase pathways and initiating inflammation.

Iqoqa.

I-esidi yeKojic (KA), 5-hydroxy-2-(hydroxymethyl)-4H-pyran-4- eyodwa, iyasetshenziswa kwezolimo, ekudleni nasezimonyweni. I-KA yaziwa ngokuba ne-antimicrobial, antifungal, antioxidant, nezinto ezibanga ukuvuvukala. Luyakhula uthando lwezimboni zezimonyo ekuthandeni i-KA ngenxa yobukhona bayo ukuphazamisa ukusebenza kwetyrosinase okuholela ekutheni isikhumba sibe mhlophe. Kunokumqoka kakhulu okwenziwa imayithokhondriya ekugcineni usimamisoluzinzo lobunjalomzimba nokuqinisekisa ukukhiqizwa okwanele kwemvikelambala, imelanin. Ngakho ke, ukungasebenzi kwemayithokhondriya kunemithelela emibi esikhunjeni. Lolu cwaningo luphenya ngengcindezi yemayithokhondriya, ukusebenza kwe-antioxidant, ukukhombisa iphrotheyini khinasi nokuvuvukala kwezinhlayiya (SK-MEL-1) zemelanoma yomuntu. Imayithokhondriya ibalulekile ekuqhubeni umsebenzi wokugaya ukudla nokunika inhlayiya amandla ayisimo se-ATP. I-KA iyahlangana namaphrotheyini asemqoka osimamisoluzinzo lobunjalomzimba bemayithokhondriya. Imiphumela yethu yathola kukhula ukulimala emolekhiyulini enkulu okuyiliphidi iphreroksideyishini nokuncipha kwezinhlayiyabugesi ezihambayo zamaphrotheyini. Ngenxa yezimo zokuncipha kwezinhlayiyabugesi ezihambayo, kwabhekwa ukukhula kokuziveza kweNrf2. Okubalulekile empilweni nasekusebenzeni kwezinhlayiya, kuyi-LON, I-LON phrothizi kuncike kuyi-ATP futhi kulawulwa ukuziveza kweSirtuin 3. Umsebenzi wemayithokhondriya kwaphazamiseka kwaboniswa ukuncipha komkhiqizo we-ATP okwaholela ekuncipheni kweLON phrothizi nokuziveza kwephrotheyini iSirtuin 3. Ukulandela ukukhula kwengcindezi yokuncipha kwezinhlayiyabugesi zamaphrotheyini, i-KA yacindezela ukuziveza kwephrotheyini yekinases kodwa kwakhulisa ukuvuvukala kwezixhumanisi zengxube ezihlanganisayo. Kwaba nokuncipha kokuziveza kwephospho-Akt, i-Akt, i-phospho-GSK3β, i-p38 a ne-ERK1/2. Isihlanganisi seNLRP3 inflammasome sibandakanya ukulungiselela nokukhuthaza. Kusilinganisobungako esineproliferation ephezulu, ukuziveza kofuzo lweNFκB kanye nephrotheyini kwakhuthazeka. Ukukhombisa izindlela kwephrotheyini ikinase kwaziwa ngokuthi ukuvuvukala kwezixhumanisi; nokho, ukuziveza kwezixhumanisi zamaphrotheyini nawofuzo avuvukele kwakhula kulandela ukwelashwa kweKA. I-inflammasome yakhuthazwa njengoba yayiboniswa ngokukhula kwamazinga loku-1 lezinhlayiya zokufanayo kwecaspase nokuziveza kweNLRP3, i--β ne- IL-6. I-KA iletha ingcindezi yemayithokhondriya ibuye icindezele amaphrotheyini osimamisoluzinzo lobunjalomzimba bemayithokhondriya. Ukukhula kokuziveza kweNrf2 bekungeza ukwehlisa ukulawulwa kokuziveza kweLON phrothizi nokukhula kokulimala kwemolekhiyuli enkulu. Izimo zokuncipha kwezinhlayiyabugesi ezihambayo ngabe kukhuthaze izindlela ze-inflammasome ezizimele ezikhombisa iphrotheyini yekhinasi. Ucwaningo lwaphetha ngokuthi i-KA yabonisa ubuthi bemayithokhondriya kulandela ukungavimbeki kwabo okunamandla ngokuthi bucindezele usimamisoluzinzo lobunjalomzimba lwemayithokhondriya, izindlela zephrotheyini khinasi nokuqala kokuvuvukala.