scholarly journals Novel Chemically Modified Curcumin (CMC) Analogs Exhibit Anti-Melanogenic Activity in Primary Human Melanocytes

2021 ◽  
Vol 22 (11) ◽  
pp. 6043
Author(s):  
Shilpi Goenka ◽  
Sanford R. Simon

Hyperpigmentation is a dermatological condition characterized by the overaccumulation and/or oversecretion of melanin pigment. The efficacy of curcumin as an anti-melanogenic therapeutic has been recognized, but the poor stability and solubility that have limited its use have inspired the synthesis of novel curcumin analogs. We have previously reported on comparisons of the anti-melanogenic activity of four novel chemically modified curcumin (CMC) analogs, CMC2.14, CMC2.5, CMC2.23 and CMC2.24, with that of parent curcumin (PC), using a B16F10 mouse melanoma cell model, and we have investigated mechanisms of inhibition. In the current study, we have extended our findings using normal human melanocytes from a darkly pigmented donor (HEMn-DP) and we have begun to study aspects of melanosome export to human keratinocytes. Our results showed that all the CMCs downregulated the protein levels of melanogenic paracrine mediators, endothelin-1 (ET-1) and adrenomedullin (ADM) in HaCaT cells and suppressed the phagocytosis of FluoSphere beads that are considered to be melanosome mimics. All the three CMCs were similarly potent (except CMC2.14, which was highly cytotoxic) in inhibiting melanin production; furthermore, they suppressed dendricity in HEMn-DP cells. CMC2.24 and CMC2.23 robustly suppressed cellular tyrosinase activity but did not alter tyrosinase protein levels, while CMC2.5 did not suppress tyrosinase activity but significantly downregulated tyrosinase protein levels, indicative of a distinctive mode of action for the two structurally related CMCs. Moreover, HEMn-DP cells treated with CMC2.24 or CMC2.23 partially recovered their suppressed tyrosinase activity after cessation of the treatment. All the three CMCs were nontoxic to human dermal fibroblasts while PC was highly cytotoxic. Our results provide a proof-of-principle for the novel use of the CMCs for skin depigmentation, since at low concentrations, ranging from 5 to 25 µM, the CMCs (CMC2.24, CMC2.23 and CMC2.5) were more potent anti-melanogenic agents than PC and tetrahydrocurcumin (THC), both of which were ineffective at melanogenesis at similar doses, as tested in HEMn-DP cells (with PC being highly toxic in dermal fibroblasts and keratinocytes). Further studies to evaluate the efficacy of CMCs in human skin tissue and in vivo studies are warranted.

2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Cynthia St. Hilaire ◽  
Hui Jin ◽  
Yuting Huang ◽  
Dan Yang ◽  
Alejandra Negro ◽  
...  

Objective: The objective of this study was to develop a patient-specific induced pluripotent stem cell (iPSC)-based disease model to understand the process by which CD73-deficiency leads to vascular calcification in the disease, Arterial Calcification due to Deficiency of CD73 (ACDC). Approach & Results: ACDC is an autosomal recessive disease resulting from mutations in the gene encoding for CD73, which converts extracellular AMP to adenosine. CD73-deficiency manifests with tortuosity and vascular calcification of the medial layer of lower-extremity arteries, a pathology associated with diabetes and chronic kidney disease. We previously identified that dermal fibroblasts isolated from ACDC patients calcify in vitro, however in vivo studies of the vasculature are limited, as murine models of CD73 deficiency do not recapitulate the human disease phenotype. Thus, we created iPSCs from ACDC patients and control fibroblasts. ACDC and Control iPSCs form teratomas when injected in immune-compromised mice, however ACDC iPSC teratomas exhibit extensive calcifications. Control and ACDC iPSCs were differentiated down the mesenchymal lineage (MSC) and while there was no difference in chondrogenesis and adipogenesis, ACDC iMSCs underwent osteogenesis sooner than control iPSC, have higher activity of tissue-nonspecific alkaline phosphatase (TNAP), and lower levels of extracellular adenosine. During osteogenic simulation, TNAP activity in ACDC cells significantly increased adenosine levels, however, not to levels needed for functional compensatory stimulation of the adenosine receptors. Inhibition of TNAP with levimisole ablates this increase in adenosine. Treatment with an A2b adenosine receptor (AR) agonist drastically reduced TNAP activity in vitro, and calcification in ACDC teratomas, as did treatment with etidronate, which is currently being tested in a clinical trial on ACDC patients. Conclusions: These results illustrate a pro-osteogenic phenotype in CD73-deficient cells whereby TNAP activity attempts to compensate for CD73 deficiency, but subsequently induces calcification that can be reversed by activation of the A2bAR. The iPSC teratoma model may be used to screen other potential therapeutics for calcification disorders.


2016 ◽  
Vol 68 (1) ◽  
pp. 125-133 ◽  
Author(s):  
Qiuyan Zhang ◽  
Dongli Li ◽  
Yue Liu ◽  
Hui Wang ◽  
Changyuan Zhang ◽  
...  

Three curcumin analogs(S1-S3) containing sulfone were investigated for their effects on human prostate cancer PC-3, colon cancer HT-29, lung cancer H1299 and pancreatic cancer BxPC-3 cells. The three compounds were approximately 16-to 96-fold more active than curcumin in these cell lines as determined by the MTT assay. The effects of these compounds on cell growth were further studied in prostate cancer PC-3 cells in both two dimensional (2D) and three dimensional (3D) cultures. S1-S3strongly inhibited the growth and induced cell death in PC-3 cells, and the effects of these compounds were associated with suppression of nuclear factor kappa B (NF-?B) transcriptional activity. Moreover, treatment of PC-3 cells with all three compounds caused a decrease in the level of phosphorylated signal transducer and activator of transcription-3 (p-STAT3) (Tyr705),but not p-STAT3(Ser727). Only S1and S2decreased the presence of phosphorylated Akt (p-Akt) in PC-3 cells. These curcumin analogs warrant further in vivo studies for anticancer activities in suitable animal models.


2019 ◽  
Vol 10 (4) ◽  
pp. 437-447 ◽  
Author(s):  
D.R. Michael ◽  
T.S. Davies ◽  
K.E. Loxley ◽  
M.D. Allen ◽  
M.A. Good ◽  
...  

Neurodegeneration has been linked to changes in the gut microbiota and this study compares the neuroprotective capability of two bacterial consortia, known as Lab4 and Lab4b, using the established SH-SY5Y neuronal cell model. Firstly, varying total antioxidant capacities (TAC) were identified in the intact cells from each consortia and their secreted metabolites, referred to as conditioned media (CM). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Crystal Violet (CV) assays of cell viability revealed that Lab4 CM and Lab4b CM could induce similar levels of proliferation in SH-SY5Y cells and, despite divergent TAC, possessed a comparable ability to protect undifferentiated and retinoic acid-differentiated cells from the cytotoxic actions of rotenone and undifferentiated cells from the cytotoxic actions of 1-methyl-4-phenylpyridinium iodide (MPP+). Lab4 CM and Lab4b CM also had the ability to attenuate rotenone-induced apoptosis and necrosis with Lab4b inducing the greater effect. Both consortia showed an analogous ability to attenuate intracellular reactive oxygen species accumulation in SH-SY5Y cells although the differential upregulation of genes encoding glutathione reductase and superoxide dismutase by Lab4 CM and Lab4b CM, respectively, implicates the involvement of consortia-specific antioxidative mechanisms of action. This study implicates Lab4 and Lab4b as potential neuroprotective agents and justifies their inclusion in further in vivo studies.


2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Li-Juan Fu ◽  
Yu-Bin Ding ◽  
Lan-Xiang Wu ◽  
Chun-Jie Wen ◽  
Qiang Qu ◽  
...  

DNA (cytosine-5-) methylation silencing of GSTP1 function occurs in prostate adenocarcinoma (PCa). Previous studies have shown that there is an inverse relationship between dietary lycopene intake and the risk of PCa. However, it is unknown whether lycopene reactivates the tumor suppressor gene glutathioneS-transferase-π(GSTP1) by demethylation of the hypermethylated CpGs that act to silence the GSTP1 promoter. Here, we demonstrated that lycopene treatment significantly decreased the methylation levels of the GSTP1 promoter and increased the mRNA and protein levels of GSTP1 in an androgen-independent PC-3 cell line. In contrast, lycopene treatment did not demethylate the GSTP1 promoter or increase GSTP1 expression in the androgen-dependent LNCaP cell line. DNA methyltransferase (DNMT) 3A protein levels were downregulated in PC-3 cells following lycopene treatment; however, DNMT1 and DNMT3B levels were unchanged. Furthermore, the long interspersed element (LINE-1) and short interspersed element ALU were not demethylated when treated by lycopene. In LNCaP cells, lycopene treatment did not affect any detected DNMT protein expression, and the methylation levels of LINE-1 and ALU were decreased. These results indicated that the protective effect of lycopene on the prostate is different between androgen-dependent and androgen-independent derived PCa cells. Further, in vivo studies should be conducted to confirm these promising results and to evaluate the potential role of lycopene in the protection of the prostate.


Blood ◽  
2008 ◽  
Vol 111 (12) ◽  
pp. 5727-5733 ◽  
Author(s):  
Jorge P. Pinto ◽  
Sara Ribeiro ◽  
Helena Pontes ◽  
Shifaan Thowfeequ ◽  
David Tosh ◽  
...  

Abstract Hepcidin is the principal iron regulatory hormone, controlling the systemic absorption and remobilization of iron from intracellular stores. Recent in vivo studies have shown that hepcidin is down-regulated by erythropoiesis, anemia, and hypoxia, which meets the need of iron input for erythrocyte production. Erythropoietin (EPO) is the primary signal that triggers erythropoiesis in anemic and hypoxic conditions. Therefore, a direct involvement of EPO in hepcidin regulation can be hypothesized. We report here the regulation of hepcidin expression by EPO, in a dose-dependent manner, in freshly isolated mouse hepatocytes and in the HepG2 human hepatocyte cell model. The effect is mediated through EPOR signaling, since hepcidin mRNA levels are restored by pretreatment with an EPOR-blocking antibody. The transcription factor C/EBPα showed a pattern of expression similar to hepcidin, at the mRNA and protein levels, following EPO and anti-EPOR treatments. Chromatin immunoprecipitation experiments showed a significant decrease of C/EBPα binding to the hepcidin promoter after EPO supplementation, suggesting the involvement of this transcription factor in the transcriptional response of hepcidin to EPO.


Foods ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 1486
Author(s):  
Valentina Nanni ◽  
Gabriele Di Marco ◽  
Gianni Sacchetti ◽  
Antonella Canini ◽  
Angelo Gismondi

Plant secondary metabolites possess chemopreventive and antineoplastic properties, but the lack of information about their exact mechanism of action in mammalian cells hinders the translation of these compounds in suitable therapies. In light of this, firstly, Origanum vulgare L. hydroalcoholic extract was chemically characterized by spectrophotometric and chromatographic analyses; then, the molecular bases underlying its antitumor activity on B16-F10 and A375 melanoma cells were investigated. Oregano extract induced oxidative stress and inhibited melanogenesis and tumor cell proliferation, triggering programmed cell death pathways (both apoptosis and necroptosis) through mitochondria and DNA damage. By contrast, oregano extract was safe on healthy tissues, revealing no cytotoxicity and mutagenicity on C2C12 myoblasts, considered as non-tumor proliferating cell model system, and on Salmonella strains, by the Ames test. All these data provide scientific evidence about the potential application of this food plant as an anticancer agent in in vivo studies and clinical trials.


2001 ◽  
Vol 21 (7) ◽  
pp. 2435-2448 ◽  
Author(s):  
Moonkyoung Um ◽  
Jun Yamauchi ◽  
Shigeaki Kato ◽  
James L. Manley

ABSTRACT TATA-binding protein (TBP) is a key general transcription factor required for transcription by all three nuclear RNA polymerases. Although it has been intensively analyzed in vitro and inSaccharomyces cerevisiae, in vivo studies of vertebrate TBP have been limited. We applied gene-targeting techniques using chicken DT40 cells to generate heterozygous cells with one copy of theTBP gene disrupted. Such TBP-heterozygous (TBP-Het) cells showed unexpected phenotypic abnormalities, resembling those of cells with delayed mitosis: a significantly lower growth rate, larger size, more G2/-M- than G1-phase cells, and a high proportion of sub-G1, presumably apoptotic, cells. Further evidence for delayed mitosis in TBP-Het cells was provided by the differential effects of several cell cycle-arresting drugs. To determine the cause of these defects, we first examined the status of cdc2 kinase, which regulates the G2/M transition, and unexpectedly observed more hyperphosphorylated, inactive cdc2 in TBP-Het cells. Providing an explanation for this, mRNA and protein levels of cdc25B, the trigger cdc2 phosphatase, were significantly and specifically reduced. These properties were all due to decreased TBP levels, as they could be rescued by expression of exogeneous TBP, including, in most but not all cases, a mutant form lacking the species-specific N-terminal domain. Our results indicate that small changes in TBP concentration can have profound effects on cell growth in vertebrate cells.


2021 ◽  
Vol 12 ◽  
Author(s):  
Jing Mu ◽  
Huisheng Ma ◽  
Hong Chen ◽  
Xiaoxia Zhang ◽  
Mengyi Ye

The aim of this study was to investigate the role of luteolin in the mechanism of ultraviolet radiation B (UVB)-induced photoaging. An in vivo photoaging model was established using UVB irradiation of bare skin on the back of rats, and an in vitro photoaging model was established using UVB irradiation of human dermal fibroblasts (HDF). Skin damage was observed using hematoxylin-eosin (HE) and Masson staining, skin and cellular reactive oxygen species (ROS) levels were detected by DHE and DCF fluorescent probes, mitochondrial membrane potential was detected by JC-1 staining, and protein expressions were detected by immunofluorescence and Western Blot. Results from animal experiments showed that luteolin reduced UVB-induced erythema and wrinkle formation. Results from cellular assays showed that luteolin inhibited UVB-induced decrease in cell viability. In addition, in vitro and in vivo experiments showed that luteolin reduced oxidative stress levels, decreased activation of matrix metalloproteinases (MMPs) and increased collagen expression. Continued cellular experiments using 3-TYP, an inhibitor of Sirtuin 3 (SIRT3), revealed a loss of cellular protection by luteolin and a decrease in collagen, suggesting that luteolin acts by targeting and promoting SIRT3. luteolin is involved in the protection of skin cells against UVB radiation-induced ageing via the SIRT3/ROS/mitogen-activated protein kinases (MAPK) axis and it may be a promising therapeutic agent for the prevention of UVB photoaging.


Molecules ◽  
2021 ◽  
Vol 26 (22) ◽  
pp. 6898
Author(s):  
Lei Wang ◽  
Hyun-Soo Kim ◽  
Jun-Geon Je ◽  
Xiaoting Fu ◽  
Caoxing Huang ◽  
...  

Skin is the largest organ of humans. Overexposure to ultraviolet (UV) is the primary environmental factor that causes skin damage. The compound, (-)-loliode, isolated from the brown seaweed Sargassum horneri, showed strong antioxidant and anti-inflammatory activities in in vitro and in vivo models. To further explore the potential of (-)-loliode in cosmetics, in the present study, we investigated the photoprotective effect of (-)-loliode in vitro in skin cells and in vivo in zebrafish. The results indicated that (-)-loliode significantly reduced intracellular reactive oxygen species (ROS) level, improved cell viability, and suppressed apoptosis of UVB-irradiated human keratinocytes. In addition, (-)-loliode remarkably attenuated oxidative damage, improved collagen synthesis, and inhibited matrix metalloproteinases expression in UVB-irradiated human dermal fibroblasts. Furthermore, the in vivo test demonstrated that (-)-loliode effectively and dose-dependently suppressed UVB-induced zebrafish damage displayed in decreasing the levels of ROS, nitric oxide, lipid peroxidation, and cell death in UVB-irradiated zebrafish. These results indicate that (-)-loliode possesses strong photoprotective activities and suggest (-)-loliode may an ideal ingredient in the pharmaceutical and cosmeceutical industries.


Biomolecules ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1240
Author(s):  
Xiaohe Li ◽  
Yunqian Zhai ◽  
Buri Xi ◽  
Wei Ma ◽  
Jianwei Zhang ◽  
...  

Skin fibrotic diseases, such as keloids, are mainly caused by pathologic scarring of wounds during healing and characterized by benign cutaneous overgrowths of dermal fibroblasts. Current surgical and therapeutic modalities of skin fibrosis are unsatisfactory. Pinocembrin, a natural flavonoid, has been shown to possess a vast range of pharmacological activities including antimicrobial, antioxidant, anti-inflammatory, and anti-tumor activities. In this study we explored the potential effect and mechanisms of pinocembrin on skin fibrosis in vitro and in vivo. In vitro studies indicated that pinocembrin dose-dependently suppressed proliferation, migration, and invasion of keloid fibroblasts and mouse primary dermal fibroblasts. The in vivo studies showed that pinocembrin could effectively alleviate bleomycin (BLM)-induced skin fibrosis and reduce the gross weight and fibrosis-related protein expression of keloid tissues in xenograft mice. Further mechanism studies indicated that pinocembrin could suppress TGF-β1/Smad signaling and attenuate TGF-β1-induced activation of skin fibroblasts. In conclusion, our results demonstrate the therapeutic potential of pinocembrin for skin fibrosis.


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