Quercetin 3-O-galactoside (Q3G) is a common dietary flavanol that has been shown to possess several bioactivities, including anti-melanogenesis. However, how Q3G exerts its anti-melanogenic effect has not been studied. The current study, therefore aimed to investigate the anti-melanogenesis potential of Q3G and elucidate the underlying action mechanism in α-melanocyte-stimulating hormone (α-MSH)-induced hyperpigmentation model of B16F10 murine melanoma cells. Results showed that α-MSH stimulation significantly increased tyrosinase (TYR) and melanin production, which were significantly downregulated by Q3G treatment. The treatment with Q3G suppressed the transcriptional and protein expressions of melanogenesis-related enzymes TYR, tyrosinase related protein-1 (TRP-1), and TRP-2, along with the melanogenic transcription factor microphthalmia-associated transcription factor (MITF) in B16F10 cells. It was shown that Q3G downregulated MITF expression and suppressed its transcriptional activity by inhibiting the cAMP-dependent protein kinase A (PKA)-mediated activation of CREB and GSK3β. In addition, MAPK-regulated MITF activation signaling was also involved in the inhibition of melanin production by Q3G. The results suggest that the anti-melanogenic properties of Q3G rationalize further studies in vivo to confirm its action mechanism and consequent utilization as a cosmetic ingredient against hyperpigmentation.

Melanin protects the skin against UV damage, whereas excessive melanin accumulation causes abnormal pigmentation and even melanoma. It has been reported that Rosa rugosa exhibits antioxidant, anti-bacterial, anti-tumor, and anti-inflammation activities. The current study evaluated the melanogenesis-suppressing effect of R. rugosa extract and its solvent fractions (H₂O, n-BuOH, 85% aq. MeOH, and n-hexane). The effect of R. rugosa on the extra/intra-cellular melanin and intracellular active tyrosinase levels, melanogenesis-related gene and protein expression, and PKA/CREB signaling pathway activation was investigated in α-MSH-induced B16F10 cells. The results showed that R. rugosa effectively suppressed melanin secretion and tyrosinase activity at non-cytotoxic concentrations. R. rugosa extract down-regulated the melanogenesis-related expression of genes and proteins of tyrosinase, microphthalmia-associated transcription factor (MITF), tyrosinase-related protein (TRP)-1, and TRP-2. Furthermore, R. rugosa effectively inhibited the phosphorylation of the PKA/CREB proteins. Finally, the total polyphenol content of R. rugosa crude extract and its H₂O, n-BuOH, 85% aq. MeOH, and n-hexane solvent fractions were 1383.9 ± 44.5, 2004.7 ± 43.4, 7270.3 ± 54.5, 2064.1 ± 34.8, and 1091.1 ± 26.2 mg gallic acid equivalent/100 g extract, respectively. The anti-melanogenesis effect of R. rugosa was suggested to be exhibited by downregulating the PKA/CREB signaling pathway potentially due to a high content of polyphenols. Overall, R. rugosa crude extract and its solvent fractions could be considered sources of bioactive ingredients that can be used against hyperpigmentation.

Obesity and related complications are significant health issues in modern society, largely attributed to a sedentary lifestyle and a carbohydrate-rich diet. Since anti-obesity drugs often come with severe side effects, preventative measures are being sought globally, including dietary changes and functional foods that can counteract weight gain. In this context, plant-based metabolites are extensively studied for their advantageous biological effects against obesity. Several plants within the Artemisia genus have been reported to possess anti-adipogenic properties, preventing adipocytes from maturing and accumulating lipids. The present study investigated the anti-adipogenic potential of two sesquiterpenoids, reynosin and santamarine, isolated from A. scoparia in adipose-induced 3T3-L1 preadipocytes. Differentiating 3T3-L1 adipocytes treated with these isolated compounds displayed fewer adipogenic characteristics compared to untreated mature adipocytes. The results indicated that cells treated with reynosin and santamarine accumulated 55.0% and 52.5% fewer intracellular lipids compared to untreated control adipocytes, respectively. Additionally, the mRNA expression of the key adipogenic marker, transcription factor PPARγ, was suppressed by 87.2% and 91.7% following 60 μM reynosin and santamarine treatment, respectively, in differentiated adipocytes. Protein expression was also suppressed in a similar manner, at 92.7% and 82.5% by 60 μM reynosin and santamarine treatment, respectively. Likewise, SERBP1c and C/EBPα were also downregulated at both gene and protein levels in adipocytes treated with samples during differentiation. Further analysis suggested that the anti-adipogenic effect of the compounds might be a result of AMPK activation and the subsequent suppression of MAPK phosphorylation. Overall, the present study suggested that sesquiterpenoids, reynosin, and santamarine were two potential bioactive compounds with anti-adipogenic properties. Further research is needed to explore other bioactive agents within A. scoparia and elucidate the in vivo action mechanisms of reynosin and santamarine.

Journal of Animal Science and Technology (JAST) is a peer-reviewed, open access journal publishing original research, review articles and notes in all fields of animal science. Topics covered by the journal include: genetics and breeding, physiology, nutrition of monogastric animals, nutrition of ruminants, animal products (milk, meat, eggs and their by-products) and their processing, grasslands and roughages, livestock environment, animal biotechnology, animal behavior and welfare.