Sains Malaysiana 52(2)(2023): 441-465

http://doi.org/10.17576/jsm-2023-5202-10

Artocarpus heterophyllus Lam. Stem Bark Inhibits Melanogenesis through Regulation of ROS, cAMP, and MAPK Pathways

(Artocarpus heterophyllus Lam. Kulit Batang Merencat Melanogenesis melalui Pengawalaturan Laluan ROS, cAMP dan MAPK)

HAZWANI MAT SAAD¹, CHUN HOE TAN², SUGUMARAN MANICKAM³, SIEW HUAH LIM⁴ & KAE SHIN SIM^1,*

¹Institute of Biological Sciences, Faculty of Science, Universiti Malaya, Jalan Profesor Diraja Ungku Aziz, 50603 Kuala Lumpur, Federal Territory, Malaysia

²Department of Biotechnology, Faculty of Applied Science, Lincoln University, 47301 Petaling Jaya, Selangor Darul Ehsan, Malaysia

³Rimba Ilmu Botanical Garden, UM Sustainability Development Centre, Level 6, Research and Innovation Management Complex, Universiti Malaya, Jalan Profesor Diraja Ungku Aziz, 50603 Kuala Lumpur, Federal Territory, Malaysia

⁴Department of Chemistry, Faculty of Science, Universiti Malaya, Jalan Profesor Diraja Ungku Aziz, 50603 Kuala Lumpur, Federal Territory, Malaysia

Received: 17 August 2022/Accepted: 23 November 2022

Abstract

Natural-based skin-lightening cosmeceutical products are attracting high popularity nowadays due to their relatively high bioavailability upon application. Artocarpus species have been highlighted with such potential, and our previous studies have reported that Artocarpus heterophyllusLam. stem bark extract exhibited a potent anti-melanogenic activity by reducing melanin content and inhibiting cellular tyrosinase activity in B16F10 melanoma cells. Hence, this study aimed to identify the bioactive fraction from A. heterophyllus Lam. stem bark and determine its anti-melanogenic mechanisms in B16F10 melanoma cells. Our results showed that a fraction (H-3) demonstrated the most pronounced anti-melanogenic effect at 12.00 µg/mL by reducing melanin content to 22.86 ± 2.90% and inhibiting cellular tyrosinase activity at treatment concentration 33-fold lower than kojic acid, without being cytotoxic against B16F10 melanoma cells. Moreover, treatment with H-3 for 24 and 48 h substantially scavenged intracellular reactive oxygen species (ROS) of hydrogen peroxide-challenged B16F10 melanoma cells by 1.8 and 4.4%, respectively. Based on the microarray profiling and qPCR analysis, H-3 downregulated Creb3l1, Creb3l2, Creb3l3, Mitf, Tyr, Tyrp1, and Dct genes in B16F10 melanoma cells, whereas the expression of Map3k20, Mapk14 (p38), and Foxo3 genes was markedly increased. Altogether, these results demonstrated that H-3 exhibited its anti-melanogenic activity in B16F10 melanoma cells through scavenging ROS and concurrent inhibition of the cAMP and activation of the p38/MAPK signaling pathways. These findings indicate that H-3 has the potential to be used as a skin lightening cosmeceutical agent in the treatment of skin hyperpigmentation.

Keywords: B16F10 melanoma cells; melanin; microarray profiling; microphthalmia-associated transcription factor; tyrosinase

Abstrak

Produk kosmetik pencerah kulit berasaskan sumber semula jadi mempunyai kepopularan yang tinggi pada masa kini kerana bioketersediaannya yang tinggi apabila digunakan. Spesies Artocarpus telah diserlahkan dengan potensi sedemikian dan kajian kami yang terdahulu telah melaporkan bahawa ekstrak kulit batang Artocarpus heterophyllus Lam. menunjukkan aktiviti anti-melanogenik yang kuat dengan menurunkan kandungan melanin serta menghalang aktiviti tirosinase sel pada sel melanoma B16F10. Oleh itu, kajian ini bertujuan untuk mengenal pasti fraksi bioaktif daripada kulit batang A. heterophyllus Lam. dan menentukan mekanisme anti-melanogenesis dalam sel melanoma B16F10. Hasil menunjukkan bahawa fraksi H-3 menunjukkan kesan anti-melanogenik yang ketara pada 12.00 µg/mL dengan menurunkan kandungan melanin kepada 22.86 ± 2.90% serta menghalang aktiviti tirosinase sel pada kepekatan 33 kali ganda lebih rendah berbanding asid kojik tanpa kesan ketoksikan pada sel melanoma B16F10. Tambahan pula, rawatan dengan H-3 selama 24 dan 48 jam dapat menghapuskan spesies oksigen reaktif (ROS) intrasel daripada sel melanoma B16F10 yang dicabar dengan H₂O₂ dengan ketara masing-masing sebanyak 1.8 dan 4.4%. Berdasarkan profil jujukan mikroarai dan analisis qPCR, H-3 menurunkan pengekspresan gen Creb3l1, Creb3l2, Creb3l3, Mitf, Tyr, Tyrp1 dan Dct dalam sel B16F10, manakala pengekspresan gen Map3k20, Mapk14 (p38), dan Foxo3 telah meningkat dengan ketara. Secara amnya, keputusan ini menunjukkan bahawa H-3 menunjukkan aktiviti anti-melanogenesis dalam sel melanoma B16F10 dengan mengikis ROS intrasel dan pada masa yang sama menghalang laluan isyarat cAMP serta mengaktifkan isyarat laluan p38/MAPK. Penemuan ini menunjukkan bahawa H-3 berpotensi untuk digunakan sebagai agen kosmetik pencerah kulit dalam rawatan hiperpigmentasi kulit.

Kata kunci: Faktor transkripsi berkaitan mikroftalmia; melanin; profil mikroatur; sel melanoma B16F10; tirosinase

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^*Corresponding author; email: simkaeshin@um.edu.my