Diallyl trisulfide (DATS) protects cardiac cells against advanced glycation end-product-induced apoptosis by enhancing FoxO3A-dependent upregulation of miRNA-210.

Diabetic cardiomyopathy is a common complication of diabetes, resulting in cardiac hypertrophy and heart failure associated with excessive reactive oxygen species and mitochondria-mediated apoptosis generation. Mitogen-activated protein kinase-c-Jun N-terminal kinase (MAPK-JNK), regulated by microRNA (miR)-210, affects mitochondrial function and is activated by advanced glycation end-products (AGE) in cardiac cells. Diallyl trisulfide (DATS), an antioxidant in garlic oil, inhibits stress-induced cardiac apoptosis. This study examined whether DATS enhances miR-210 expression to attenuate cardiac apoptosis. We investigated the DATS-mediated attenuation mechanism of AGE-enhanced cardiac apoptosis by modulating miR-210 and its upstream transcriptional regulator, FoxO3a. We found FoxO3a binding sites in the miR-210 promoter region. Our results indicated that DATS treatment inhibited AGE-induced JNK activation, phosphoprotein c-Jun nuclear transactivation, and cardiac apoptosis and reversed the AGE-induced reduction in cardiac miR-210 levels. The luciferase activity after DATS treatment was significantly lower than that of the control and was reversed following AGE treatment. We also showed that FoxO3a, upregulated by DATS treatment, may bind to the miR-210 promoter to enhance its expression and downregulates JNK expression to attenuate AGE-induced cardiac apoptosis. Oral administration of DATS enhanced FoxO3a expression in the heart and reduced diabetes-induced heart apoptosis. Our findings indicate that DATS mediates AGE-induced cardiac cell apoptosis attenuation by promoting FoxO3a nuclear transactivation to enhance miR-210 expression and regulate JNK activation. Our results suggest that DATS can be used as a cardioprotective agent, and miR-210 is a critical regulator in inhibiting diabetic cardiomyopathy.

Activation of PI3K/Akt mediates the protective effect of diallyl trisulfide on doxorubicin induced cardiac apoptosis.

Diallyl trisulfide (DATS), an organosulfide compound derived from garlic, is renowned for its potent antioxidant properties, particularly in countering the generation of reactive oxygen species (ROS). It has also gained recognition as a potential agent for preventing heart-related conditions. Doxorubicin (Dox), a commonly used chemotherapeutic drug, is known to induce severe cardiac complications by promoting ROS production. Therefore, it was imperative to investigate whether DATS possesses cardioprotective capabilities against Dox-induced cardiac apoptosis and elucidate the underlying mechanisms. In this study, we observed that the intracellular ROS levels and cardiac apoptosis were heightened in H9c2 cells exposed to Dox (1 µM). However, treatment with 10 µM DATS effectively mitigated the Dox-induced ROS generation and apoptotic signaling, concurrently activating the PI3K/Akt pathway. Notably, the anti-apoptotic effects of DATS were attenuated when PI3K siRNA and the LY294002 PI3K inhibitor were employed. Furthermore, the TUNEL assay results demonstrated a significant reduction in Dox-induced apoptosis with DATS treatment. In summary, our findings indicate that DATS can activate the PI3K/Akt pathway, reducing ROS production in cardiac cells exposed to Dox, and subsequently rescue cardiac cells from apoptosis.

Paeoniflorin found in Paeonia lactiflora root extract inhibits melanogenesis by regulating melanin-related signal transduction in B16F10 cells.

BACKGROUND: Skin pigmentation is modulated by various processes, with melanogenesis playing a key role. Melanin is synthesized by the catalysis of melanogenesis-related enzymes, such as tyrosinase and tyrosine-related proteins TRP-1 and TRP-2. Paeoniflorin is the main bioactive component of Paeonia suffruticosa Andr., Paeonia lactiflora., or Paeonia veitchii Lynch and has been used for centuries for its anti-inflammatory, anti-oxidant, and anti-carcinogenic properties. AIMS & METHODS: In this study, melanin biosynthesis in mouse melanoma (B16F10) cells was induced using α-melanocyte-stimulating hormone (α-MSH), and then cells were co-treated with paeoniflorin to evaluate its potential anti-melanogenic effect. RESULTS: α-MSH stimulation increased melanin content, tyrosinase activity, and melanogenesis-related markers in a dose-dependent manner. However, treatment with paeoniflorin reversed α-MSH-induced upregulation of melanin content and tyrosinase activity. Furthermore, paeoniflorin inhibited cAMP response element-binding protein activation and TRP-1, TRP-2, and microphthalmia-associated transcription factor protein expression in α-MSH-stimulated B16F10 cells. CONCLUSION: Overall, these findings show the potential of paeoniflorin as a depigmenting agent for cosmetic products.

Galangin Reverses H2O2-Induced Dermal Fibroblast Senescence via SIRT1-PGC-1α/Nrf2 Signaling.

UV radiation and H2O2 are the primary factors that cause skin aging. Both trigger oxidative stress and cellular aging. It has been reported that deacetylase silent information regulator 1 (SIRT1), a longevity gene, enhances activation of NF-E2-related factor-2 (Nrf2), as well as its downstream key antioxidant gene hemeoxygenase-1 (HO-1), to protect cells against oxidative damage by deacetylating the transcription coactivator PPARγ coactivator-1α (PGC-1α). Galangin, a flavonoid, possesses anti-oxidative and anti-inflammatory potential. In the present study, we applied Ultraviolet B/H2O2-induced human dermal fibroblast damage as an in vitro model and UVB-induced photoaging of C57BL/6J nude mice as an in vivo model to investigate the underlying dermo-protective mechanisms of galangin. Our results indicated that galangin treatment attenuates H2O2/UVB-induced cell viability reduction, dermal aging, and SIRT1/PGC-1α/Nrf2 signaling activation. Furthermore, galangin treatment enhanced Nrf2 activation and nuclear accumulation, in addition to inhibiting Nrf2 degradation. Interestingly, upregulation of antioxidant response element luciferase activity following galangin treatment indicated the transcriptional activation of Nrf2. However, knockdown of SIRT1, PGC-1α, or Nrf2 by siRNA reversed the antioxidant and anti-aging effects of galangin. In vivo evidence further showed that galangin treatment, at doses of 12 and 24 mg/kg on the dorsal skin cells of nude mice resulted in considerably reduced UVB-induced epidermal hyperplasia and skin senescence, and promoted SIRT1/PGC-1α/Nrf2 signaling. Furthermore, enhanced nuclear localization of Nrf2 was observed in galangin-treated mice following UVB irradiation. In conclusion, our data indicated that galangin exerts anti-photoaging and antioxidant effects by promoting SIRT1/PGC-1α/Nrf2 signaling. Therefore, galangin is a potentially promising agent for cosmetic skin care products against UV-induced skin aging.

Protective effects of galangin against H2O2/UVB-induced dermal fibroblast collagen degradation via hsa-microRNA-4535-mediated TGFß/Smad signaling.

This study aimed to investigate the mechanism underlying the protective effects of galangin against H2O2/UVB-induced damage using in vitro and in vivo models of photodamage. Moreover, we identified the involvement of miRNA regulation in this process. The H2O2/UVB-treated HS68 human dermal fibroblasts and UVB-induced C57BL/6J nude mice were used as in vitro and in vivo models of photodamage. The results showed that galangin treatment alleviated H2O2/UVB-induced reduction in cell viability, TGFß/Smad signaling impairment, and dermal aging. Based on the results of microRNA array analyses and database searches, hsa-miR-4535 was identified as a potential candidate miRNA that targets Smad4. In vitro, galangin treatment activated Smad2/3/4 complex and inhibited hsa-miR-4535 expression in H2O2/UVB-exposed cells. In vivo, topical application of low (12 mg/kg) and high doses (24 mg/kg) of galangin to the dorsal skin of C57BL/6J nude mice significantly alleviated UVB-induced skin photodamage by promoting TGFß/Smad collagen synthesis signaling, reducing epidermal hyperplasia, wrinkle formation, and skin senescence, as well as inhibiting hsa-miR-4535 expression. Taken together, our findings indicate a link between hsa-miR-4535 and TGFß/Smad collagen synthesis signaling and suggest these factors to be involved in the photo-protective mechanism of galangin in dermal fibroblasts against H2O2/UVB-induced aging. The evidence indicated that galangin with anti-aging properties can be considered as a supplement in skin care products.

MicroRNA-210 repression facilitates advanced glycation end-product (AGE)-induced cardiac mitochondrial dysfunction and apoptosis via JNK activation.

Hyperglycemia results in the formation of reactive oxygen species which in turn causes advanced glycation end products (AGEs) formation, leading to diabetic cardiomyopathy. Our previous study showed that AGE-induced reactive oxygen species-dependent apoptosis is mediated via protein kinase C delta (PKCδ)-enhanced mitochondrial damage in cardiomyocytes. By using microRNA (miRNA) database, miRNA-210 was predicted to target c-Jun N-terminal kinase (JNK), which were previously identified as downstream of PKCδ in regulating mitochondrial function. Therefore, we hypothesized that miR-210 mediates PKCδ-dependent upregulation of JNK to cause cardiac mitochondrial damage and apoptosis following AGE exposure. AGE-exposed cells showed activated cardiac JNK, PKCδ, and apoptosis, which were reversed by treatment with a JNK inhibitor and PKCδ-KD (deficient kinase). Cardiac miR-210 and mitochondrial function were downregulated following AGE exposure. Furthermore, JNK was upregulated and involved in AGE-induced mitochondrial damage. Interestingly, luciferase activity of the miR-210 mimic plus JNK WT-3'-untranslated region overexpressed group was significantly lower than that of miR-210 mimic plus JNK MT-3'UTR group, indicating that JNK is a target of miR-210. Moreover, JNK activation induced by AGEs was reduced by treatment with the miR-210 mimic and reversed by treatment with the miR-210 inhibitor, indicating the regulatory function of miR-210 in JNK activation following AGE exposure. Additionally, JNK-dependent mitochondrial dysfunction and apoptosis were reversed following treatment with the miR-210 mimic, while the miR-210 inhibitor showed no effect on JNK-induced mitochondrial dysfunction and apoptosis in AGE-exposed cardiac cells. Taken together, our study showed that PKCδ-enhanced JNK-dependent mitochondrial damage is mediated through the reduction of miR-210 in cardiomyocytes following AGE exposure.

Extracts of Jasminum sambac flowers fermented by Lactobacillus rhamnosus inhibit H2 O2 - and UVB-induced aging in human dermal fibroblasts.

Ultraviolet (UV) irradiation is a crucial factor that leads to skin photoaging and results in increased DNA damage, oxidative stress, and collagen degradation. Jasmine flowers have been utilized as a traditional medicine in Asia to treat various diseases, including dermatitis, diarrhea, and fever. Furthermore, the fermented broth of Lactobacillus rhamnosus has been reported to exert protective effects on the skin. In the present study, jasmine flower extract was fermented with L. rhamnosus. We investigated the antioxidant and collagen-promoting effects on UVB/H2 O2 -induced HS68 dermal fibroblast cell damage. The results indicated that treatment with the fermented flower extracts of Jasminum sambac (F-FEJS) could enhance the viability of HS68 cells. Furthermore, the UVB/H2 O2 -induced excessive production of reactive oxygen species, degradation of collagen, activation of MAPKs, including P38, ERK, and JNK, and premature senescence were remarkably attenuated by F-FEJS in dermal fibroblast cells. The nuclear accumulation of p-c-jun, which is downstream of MAPK, and the inactivation of p-smad2/3, which is one of the crucial transcription factors that enhance collagen synthesis, were reversed in response to F-FEJS treatment in UVB/H2 O2 -exposed cells. Notably, the expression of antioxidant genes, such as HO-1, and the nuclear translocation of Nrf2 were further enhanced by F-FEJS in UVB/H2 O2 -treated cells. Interestingly, the F-FEJS-induced increase in ARE luciferase activity indicated the activation of Nrf2/ARE signaling. In conclusion, our findings demonstrated that F-FEJS can effectively ameliorate UVB/H2 O2 -induced dermal cell aging and may be considered a promising ingredient in skin aging therapy.

Seven traditional Chinese herbal extracts fermented by Lactobacillus rhamnosus provide anti-pigmentation effects by regulating the CREB/MITF/tyrosinase pathway.

Skin pigmentation is resulted from several processes, such as melanin synthesis transportation and abnormal melanin accumulation in keratinocytes. Various studies have suggested that seven traditional Chinese herbal extracts from Atractylodes macrocephala, Paeonia lactiflora, Bletilla striata, Poria cocos, Dictamnus dasycarpus, Ampelopsis japonica and Tribulus terrestris (which we collectively named ChiBai), show several protective effects toward skin-related diseases. Lactobacillus rhamnosus, a lactic acid bacterium, has been reported to treat skin inflammation and atopic dermatitis. In this study, the broth produced by the cofermentation of ChiBai with Lactobacillus rhamnosus was studied for its effects on skin pigmentation through in vitro and in vitro experiments. In the in vitro experiments, we found that the fermented broth of ChiBai (FB-ChiBai) suppressed alpha-melanocyte stimulating hormone (α-MSH)-induced melanogenesis in B16F0 murine melanoma cells without any cytotoxicity at a concentration of 0.5%. FB-ChiBai significantly attenuated melanin production, tyrosinase activities and melanogenesis-related signaling pathways. Treatment with FB-ChiBai also reduced the nuclear translocation and promoter binding activities of MITF. In the in vivo experiments, FB-ChiBai was topically applied to the dorsal skin of C57BL/6J nude mice and concurrently irradiated with UVB, three times a week for 8 weeks. The results indicated that FB-ChiBai alleviated UVB-induced hyperpigmentation by reducing epidermal hyperplasia and inhibiting the CREB/MITF/tyrosinase pathway. In conclusion, our data indicated that the anti-melanogenic effects of FB-ChiBai are mediated by the inhibition of CREB/MITF/tyrosinase signaling pathway. The findings suggest that FB-ChiBai can protect against UV-B irradiation and that it might be used as an agent in cosmetic products to protect against UVB-induced hyperpigmentation.

Diallyl Trisulfide (DATS) Suppresses AGE-Induced Cardiomyocyte Apoptosis by Targeting ROS-Mediated PKCδ Activation.

Chronic high-glucose exposure results in the production of advanced glycation end-products (AGEs) leading to reactive oxygen species (ROS) generation, which contributes to the development of diabetic cardiomyopathy. PKCδ activation leading to ROS production and mitochondrial dysfunction involved in AGE-induced cardiomyocyte apoptosis was reported in our previous study. Diallyl trisulfide (DATS) is a natural cytoprotective compound under various stress conditions. In this study, the cardioprotective effect of DATS against rat streptozotocin (STZ)-induced diabetic mellitus (DM) and AGE-induced H9c2 cardiomyoblast cell/neonatal rat ventricular myocyte (NRVM) damage was assessed. We observed that DATS treatment led to a dose-dependent increase in cell viability and decreased levels of ROS, inhibition of PKCδ activation, and recuded apoptosis-related proteins. Most importantly, DATS reduced PKCδ mitochondrial translocation induced by AGE. However, apoptosis was not inhibited by DATS in cells transfected with PKCδ-wild type (WT). Inhibition of PKCδ by PKCδ-kinase-deficient (KD) or rottlerin not only inhibited cardiac PKCδ activation but also attenuated cardiac cell apoptosis. Interestingly, overexpression of PKCδ-WT plasmids reversed the inhibitory effects of DATS on PKCδ activation and apoptosis in cardiac cells exposed to AGE, indicating that DATS may inhibit AGE-induced apoptosis by downregulating PKCδ activation. Similar results were observed in AGE-induced NRVM cells and STZ-treated DM rats following DATS administration. Taken together, our results suggested that DATS reduced AGE-induced cardiomyocyte apoptosis by eliminating ROS and downstream PKCδ signaling, suggesting that DATS has potential in diabetic cardiomyopathy (DCM) treatment.

Roles of p38α and p38ß mitogen­activated protein kinase isoforms in human malignant melanoma A375 cells.

Skin cancer is one of the most common cancers worldwide. Melanoma accounts for ~5% of skin cancers but causes the large majority of skin cancer­related deaths. Recent discoveries have shown that the mitogen­activated protein kinase (MAPK) signaling pathway is critical for melanoma development and progression. Many oncogenic pathways that cause melanoma tumorigenesis have been identified, most of which are due to RAF/MEK/ERK (MAPK) pathway activation. However, the precise role of p38 remains unclear. Using specific short hairpin (sh) RNA to silence p38α and p38ß, the present findings demonstrated that p38α was a crucial factor in regulating cell migration in the A375 melanoma cell line. Silencing p38α downregulated the expression of epithelial­mesenchymal transition markers, such as matrix metallopeptidase (MMP) 2, MMP9, twist family bHLH transcription factor 1, snail family transcriptional repressor 1 and vimentin, while mesenchymal­epithelial transition markers, such as E­cadherin, were upregulated. Of note, the results also demonstrated that p38α silencing impaired vascular endothelial growth factor expression, which regulates tumor angiogenesis. Furthermore, p38α knockdown inhibited cell proliferation in melanoma cells. In addition, silencing p38α induced senescence­like features, but not cell cycle arrest. Expression of the senescence markers p16, p21, p53 and ß­galactosidase was upregulated, and an increase in the number of senescence­associated ß­galactosidase­positive cells was observed in a p38α knockdown stable clone. However, no significant difference was found between control and p38ß stable knockdown cells. Taken together, the present results suggested that p38α knockdown impaired migration and proliferation, and increased senescence, in A375 melanoma cells. However, p38ß may not be involved in melanoma tumorigenesis. Therefore, targeting p38α may be a valuable approach towards inhibiting tumor growth and metastasis in patients with melanoma.