1
|
Tüzün BS, Karadağ BT, Oran S, Öztürk Ş, Yilmaz FF, Fafal T, Kivçak B. Determination of phytochemical contents by LC/QTOF/MS and evaluation of in-vitro biological activities of 2 Peltigera lichens from Bursa. AN ACAD BRAS CIENC 2024; 96:e20230657. [PMID: 38896692 DOI: 10.1590/0001-3765202420230657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 02/03/2024] [Indexed: 06/21/2024] Open
Abstract
Lichens are symbiotic associations of algae and fungi. They are edible as food and have been used in traditional medicine for years. It is aimed to screen Peltigera praetextata (Flörke ex Sommerf.) Zopfand and Peltigera elisabethae Gyeln. phytochemically by LC/QTOF/MS and according to the constituents to evaluate the antioxidant, tyrosinase inhibitory, and antibacterial activities. In total 54 of metabolites detected by LC/QTOF/MS were common in both species. According to LC/QTOF/MS scanning results, alkaloids, iridoid glycosides, phenolics, cyanogenetic glycosides, and terpenic structures were detected. DPPH, ABTS, superoxide radical scavenging activities, and metal chelating capacity IC50 values were 84.55, 9.349; 51.27, 9.127; 95.01, 58.65 and 20.57, 70.08 µg/mL., respectively. The CUPRAC reducing power was determined as 4.69 and 9.57 TEACCUPRAC, respectively. Tyrosinase inhibitor activity were found to be 86.95 and 196.7 µg/mL. Both lichens did not show antimicrobial effects. As a result of the antioxidant and tyrosinase inhibitor activities it was seen that their activities were significant and further in vivo studies could be carried out on this lichens.
Collapse
Affiliation(s)
- Burcu S Tüzün
- Ege University, Department of Pharmacognosy, Faculty of Pharmacy, Erzene District, Bornova, 35040, Izmır, Turkıye
| | - Başak T Karadağ
- Ege University, Department of Pharmacognosy, Faculty of Pharmacy, Erzene District, Bornova, 35040, Izmır, Turkıye
| | - Seyhan Oran
- Uludag University, Deparment of Botany, Faculty of Science, Görükle District, Nilüfer, 16285, Bursa, Turkıye
| | - Şule Öztürk
- Uludag University, Deparment of Botany, Faculty of Science, Görükle District, Nilüfer, 16285, Bursa, Turkıye
| | - Fethiye F Yilmaz
- Ege University, Deparment of Pharmaceutical Microbiology, Faculty of Pharmacy, Erzene District, Bornova, 35040, Izmır, Turkıye
| | - Tuğçe Fafal
- Ege University, Department of Pharmacognosy, Faculty of Pharmacy, Erzene District, Bornova, 35040, Izmır, Turkıye
| | - Bijen Kivçak
- Ege University, Department of Pharmacognosy, Faculty of Pharmacy, Erzene District, Bornova, 35040, Izmır, Turkıye
| |
Collapse
|
2
|
Demirbaş A, Eker H. Is there a correlation the between the second to fourth digit ratio and vitiligo? A cross‐sectional study. J Cosmet Dermatol 2022; 21:3146-3151. [DOI: 10.1111/jocd.15069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 04/22/2022] [Accepted: 05/05/2022] [Indexed: 11/30/2022]
Affiliation(s)
- Abdullah Demirbaş
- Department of Dermatology, Faculty of Medicine Kocaeli University Kocaeli Turkey
| | - Hediye Eker
- Department of Dermatology Selçuk University Konya Turkey
| |
Collapse
|
3
|
Khumpeerawat P, Duangjinda M, Phasuk Y. Factors affecting gene expression associated with the skin color of black-bone chicken in Thailand. Poult Sci 2021; 100:101440. [PMID: 34547619 PMCID: PMC8463778 DOI: 10.1016/j.psj.2021.101440] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 07/03/2021] [Accepted: 08/15/2021] [Indexed: 11/19/2022] Open
Abstract
The objective of this study was to investigate the effect of breed, sex, and age on the gene expression level of melanocortin 1 receptor (MC1R), DOPA chrome tautomerase (DCT), tyrosinase-related protein 1 (TYRP1), tyrosinase (TYR), and agouti signaling protein (ASIP) genes in Thai commercial chicken lines. All chicken have received Newscastle vaccination, and no antibiotics or any drugs were used in this study. Four chicken breeds including Black-Chinese, KU-Phuparn, Sri Mok, and Pradu Hang Dam were used in this study. These breeds can be classified by their skin color into 3 group including black (Black Chinese and KU-Phuparn), light black (Sri Mok), and yellowish white (Pradu Hang Dam). One hundred chickens per breed were used in this study. Breast skin tissue was randomly collected from 8 chickens (4 males, 4 females) per breed at 4, 8, 12, and 16 wk of age. The mRNA expression was analyzed using qRT-PCR and the gene expression level was calculated as 2-ΔΔCT. From the results, breed significantly (P < 0.01) affected the expression level for the 5 genes evaluated. Birds with the black skin color had greater TYRP1 and TYR gene expression when compared to chickens with light black and yellowish-white skin color, respectively. Whereas, chickens with yellowish-white skin color had greater ASIP gene expression when compared to chickens having the other skin colors. Sex significantly affected DCT, TYRP1, and TYR gene expression where the gene expression in males was greater when compared to females (P < 0.05). Age affected all gene expression levels (P < 0.01). At 4 wk of age, MC1R, DCT, TYRP1, and TYR gene expression was the highest and decreased as bird age increased (P < 0.05); however, ASIP gene expression was greatest at 8 wk of age. After 8 wk of age all gene expression for the genes evaluated in this study decreased as age increased. In addition, an interaction between breed and sex (P < 0.05) impacted DCT and ASIP gene expression. The results from this study showed that all genes evaluated can be used as candidate markers to further improve the blackness of the chicken's skin because the most desired skin color is black in the Thai black-bone chicken population.
Collapse
Affiliation(s)
- Panuwat Khumpeerawat
- Department of Animal Science, Faculty of Agricultural, Khon Kaen University, Mueang Khon Kaen 40000, Thailand
| | - Monchai Duangjinda
- Department of Animal Science, Faculty of Agricultural, Khon Kaen University, Mueang Khon Kaen 40000, Thailand; Network Center for Animal Breeding and Omics Research, Faculty of Agricultural, Khon Kaen University, Mueang Khon Kaen 40000, Thailand.
| | - Yupin Phasuk
- Department of Animal Science, Faculty of Agricultural, Khon Kaen University, Mueang Khon Kaen 40000, Thailand; Network Center for Animal Breeding and Omics Research, Faculty of Agricultural, Khon Kaen University, Mueang Khon Kaen 40000, Thailand
| |
Collapse
|
4
|
Al Samahy O, Othman D, Gad D, Baky Fahmy MA. Efficacy of topical testosterone in management of scrotal hypoplasia and agenesis. J Pediatr Urol 2021; 17:515.e1-515.e8. [PMID: 33678558 DOI: 10.1016/j.jpurol.2021.02.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 01/19/2021] [Accepted: 02/15/2021] [Indexed: 02/08/2023]
Abstract
BACKGROUND Scrotal hypoplasia or agenesis may posses difficulty during orchidopexy or end with social anxiety around excessively small scrotal size when compared to peers, and where there may be concerns regarding the future sexual life. OBJECTIVE Any conservative modality applicable to ameliorate scrotal underdevelopment partially or completely will be useful either solely or before reconstructive surgery. STUDY DESIGN Seventeen child (3-8 years) were diagnosed with bilateral scrotal hypoplasia (SH) in 5 unilateral in 7, bilateral scrotal agenesis (SA) diagnosed in 4 cases, and unilateral in one. Testicles are either undescended, ectopic, or normal. All cases managed by Testogel 1% topical testosterone for 4 weeks. Clinical assessment by measurements of the scrotal skin surface area (scrotal length multiplied by width) and scrotal corrugations counting. Inguinal and renal ultrasound done for all cases and karyotyping for cases of agenesis and cases with bilateral undescended testicles. Total and free testosterone, LH, FSH and AMH hormones were assisted before treatment, weekly and one week after therapy. Data analyzed and evaluated, difference of means used to test for statistically significant differences between scores of scrotal development. RESULTS Free and total testosterone elevated in the 1st week of treatment, but restored to normal or higher levels in 60% of cases at the 2nd week. Satisfactory response (Increasing numbers of scrotal rugae or scrotal surface area by 30-50% above the pretreatment status) obtained in 85% and 60% of unilateral and bilateral SH, but only a partial response (10-20% increase) was gained in 40% of cases with agenesis. No major adverse effect was appreciated. DISCUSSION Response of some cases of SH to topical testosterone indicates presence of remnants of labioscrotal folds with testosterone receptors (Bell et al., 1971) [1]. Testosterone replacement therapy can improve the signs and well-being of a hypogonadal male by restoring serum testosterone concentrations to physiologic levels. In this study the mean average testosterone concentration one week after application of testogel was 13.47 ± 2.45 and 12.12 ± 2.5 within 2nd, 4th week, and after cessation of treatment. Anti-Mullerian hormone is significantly low in 12 cases; mainly in cases of SA (P-value <0.001). CONCLUSION Short term topical testosterone proved to be effective in a considerable percentage of cases of either bilateral or unilateral scrotal hypoplasia; with a subsequent increase in scrotal surface area and number of rugae, it may substitutes the indication for surgical reconstruction. Long term follow up is a limitation of this study.
Collapse
Affiliation(s)
- Omar Al Samahy
- Pediatric Surgery, Al Azhar Faculty of Medicine for Girls, Egypt
| | - Doa Othman
- Pediatric Surgery, Al Azhar Faculty of Medicine for Girls, Egypt
| | - Dalia Gad
- Pediatric Surgery, Al Azhar Faculty of Medicine for Girls, Egypt
| | - M A Baky Fahmy
- Pediatric Surgery, Al Azhar Faculty of Medicine for Girls, Egypt.
| |
Collapse
|
5
|
Kang HY, Lee JW, Papaccio F, Bellei B, Picardo M. Alterations of the pigmentation system in the aging process. Pigment Cell Melanoma Res 2021; 34:800-813. [PMID: 34048137 DOI: 10.1111/pcmr.12994] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 05/17/2021] [Accepted: 05/19/2021] [Indexed: 01/10/2023]
Abstract
Human skin aging is a natural phenomenon that results from continuous exposure to intrinsic (time, genetic factors, hormones) as well as extrinsic factors (UV exposure, pollution, tobacco). In areas that are frequently exposed to the sun, photoaging blends with the process of intrinsic aging, resulting in an increased senescent cells number and consequently accelerating the aging process. The severity of photodamage depends on constitutional factors, including skin phototype (skin color, tanning capacity), intensity, and duration of sunlight/UV exposure. Aging affects nearly every aspect of cutaneous biology, including pigmentation. Clinically, the phenotype of age pigmented skin has a mottled, uneven color, primarily due to age spots, with or without hypopigmentation. Uneven pigmentation might be attributed to the hyperactivation of melanocytes, altered distribution of pigment, and turnover. In addition to direct damage to pigment-producing cells, photodamage alters the physiological crosstalk between keratinocytes, fibroblasts, endothelial cells, and melanocytes responsible for natural pigmentation homeostasis. Interestingly, age-independent diffuse expression of senescence-associated markers in the dermal and epidermal compartment is also associated with vitiligo, suggesting that premature senescence plays an important role in the pathology.
Collapse
Affiliation(s)
- Hee Young Kang
- Department of Dermatology, Ajou University School of Medicine, Suwon, Korea
| | - Jin Wook Lee
- Department of Medical Sciences, Ajou University Graduate School of Medicine, Suwon, Korea.,Department of Dermatology, College of Medicine, Chungbuk National University, Cheongju, Korea
| | - Federica Papaccio
- Cutaneous Physiopathology and Integrated Center of Metabolomics Research, San Gallicano Dermatological Institute, IRCCS, Rome, Italy
| | - Barbara Bellei
- Cutaneous Physiopathology and Integrated Center of Metabolomics Research, San Gallicano Dermatological Institute, IRCCS, Rome, Italy
| | - Mauro Picardo
- Cutaneous Physiopathology and Integrated Center of Metabolomics Research, San Gallicano Dermatological Institute, IRCCS, Rome, Italy
| |
Collapse
|
6
|
Béziers P, Ducrest AL, Simon C, Roulin A. Circulating testosterone and feather-gene expression of receptors and metabolic enzymes in relation to melanin-based colouration in the barn owl. Gen Comp Endocrinol 2017; 250:36-45. [PMID: 28457648 DOI: 10.1016/j.ygcen.2017.04.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Revised: 03/11/2017] [Accepted: 04/26/2017] [Indexed: 10/19/2022]
Abstract
Knowledge of how and why secondary sexual characters are associated with sex hormones is important to understand their signalling function. Such a link can occur if i) testosterone participates in the elaboration of sex-traits, ii) the display of an ornament triggers behavioural response in conspecifics that induce a rise in testosterone, or iii) genes implicated in the elaboration of a sex-trait pleiotropically regulate testosterone physiology. To evaluate the origin of the co-variation between melanism and testosterone, we measured this hormone and the expression of enzymes involved in its metabolism in feathers of barn owl (Tyto alba) nestlings at the time of melanogenesis and in adults outside the period of melanogenesis. Male nestlings displaying smaller black feather spots had higher levels of circulating testosterone, potentially suggesting that testosterone could block the production of eumelanin pigments, or that genes involved in the production of small spots pleiotropically regulate testosterone production. In contrast, the enzyme 5α-reductase, that metabolizes testosterone to DHT, was more expressed in feathers of reddish-brown than light-reddish nestlings. This is consistent with the hypothesis that testosterone might be involved in the expression of reddish-brown pheomelanic pigments. In breeding adults, male barn owls displaying smaller black spots had higher levels of circulating testosterone, whereas in females the opposite result was detected during the rearing period, but not during incubation. The observed sex- and age-specific co-variations between black spottiness and testosterone in nestling and adult barn owls may not result from testosterone-dependent melanogenesis, but from melanogenic genes pleiotropically regulating testosterone, or from colour-specific life history strategies that influence testosterone levels.
Collapse
Affiliation(s)
- Paul Béziers
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland.
| | - Anne-Lyse Ducrest
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Céline Simon
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Alexandre Roulin
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| |
Collapse
|
7
|
Hernando B, Ibarrola-Villava M, Fernandez LP, Peña-Chilet M, Llorca-Cardeñosa M, Oltra SS, Alonso S, Boyano MD, Martinez-Cadenas C, Ribas G. Sex-specific genetic effects associated with pigmentation, sensitivity to sunlight, and melanoma in a population of Spanish origin. Biol Sex Differ 2016; 7:17. [PMID: 26998216 PMCID: PMC4797181 DOI: 10.1186/s13293-016-0070-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 03/07/2016] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Human pigmentation is a polygenic quantitative trait with high heritability. In addition to genetic factors, it has been shown that pigmentation can be modulated by oestrogens and androgens via up- or down-regulation of melanin synthesis. Our aim was to identify possible sex differences in pigmentation phenotype as well as in melanoma association in a melanoma case-control population of Spanish origin. METHODS Five hundred and ninety-nine females (316 melanoma cases and 283 controls) and 458 males (234 melanoma cases and 224 controls) were analysed. We genotyped 363 polymorphisms (single nucleotide polymorphisms (SNPs)) from 65 pigmentation gene regions. RESULTS When samples were stratified by sex, we observed more SNPs associated with dark pigmentation and good sun tolerance in females than in males (107 versus 75; P = 2.32 × 10(-6)), who were instead associated with light pigmentation and poor sun tolerance. Furthermore, six SNPs in TYR, SILV/CDK2, GPR143, and F2RL1 showed strong differences in melanoma risk by sex (P < 0.01). CONCLUSIONS We demonstrate that these genetic variants are important for pigmentation as well as for melanoma risk, and also provide suggestive evidence for potential differences in genetic effects by sex.
Collapse
Affiliation(s)
- Barbara Hernando
- Department of Medicine, Jaume I University of Castellon, Av. Sos Baynat s/n, 12071 Castellon, Spain
| | - Maider Ibarrola-Villava
- Department of Medical Oncology, Biomedical Research Institute - INCLIVA, University of Valencia, Av. Menendez Pelayo 4 accesorio, 46010 Valencia, Spain
| | - Lara P Fernandez
- Molecular Oncology and Nutritional Genomics of Cancer Group, IMDEA Food Institute, CEI UAM + CSIC, Madrid, Spain
| | - Maria Peña-Chilet
- Department of Medical Oncology, Biomedical Research Institute - INCLIVA, University of Valencia, Av. Menendez Pelayo 4 accesorio, 46010 Valencia, Spain
| | - Marta Llorca-Cardeñosa
- Department of Medical Oncology, Biomedical Research Institute - INCLIVA, University of Valencia, Av. Menendez Pelayo 4 accesorio, 46010 Valencia, Spain
| | - Sara S Oltra
- Department of Medical Oncology, Biomedical Research Institute - INCLIVA, University of Valencia, Av. Menendez Pelayo 4 accesorio, 46010 Valencia, Spain
| | - Santos Alonso
- Department of Genetics, Physical Anthropology and Animal Physiology, University of the Basque Country UPV/EHU, Leioa, Bizkaia Spain
| | - Maria Dolores Boyano
- Department of Cell Biology and Histology, University of the Basque Country UPV/EHU, Leioa, Bizkaia Spain.,BioCruces Health Research Institute, Cruces University Hospital, Cruces-Barakaldo, Bizkaia Spain
| | - Conrado Martinez-Cadenas
- Department of Medicine, Jaume I University of Castellon, Av. Sos Baynat s/n, 12071 Castellon, Spain
| | - Gloria Ribas
- Department of Medical Oncology, Biomedical Research Institute - INCLIVA, University of Valencia, Av. Menendez Pelayo 4 accesorio, 46010 Valencia, Spain
| |
Collapse
|
8
|
Nishio H, Mizuno K, Moritoki Y, Kamisawa H, Naiki T, Kurokawa S, Nakane A, Okada A, Yasui T, Hayashi Y. Hemiscrotal agenesis: Pathogenesis and management strategies. Int J Urol 2016; 23:523-526. [PMID: 26990159 DOI: 10.1111/iju.13079] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 02/16/2016] [Indexed: 12/31/2022]
Abstract
Hemiscrotal agenesis is among the rarest anomalies in scrotal development disorders. As it has only been reported in three cases, the clinical manifestations remain unclear. We report a case of hemiscrotal agenesis with ipsilateral cryptorchidism. Based on the thermal assessment of the scrotum, concurrent scrotoplasty and orchiopexy were carried out, and the scrotoplasty improved the thermal environment of the fixed left testis. Furthermore, the low expression of androgen receptor and steroid-5-alpha-reductase, alpha polypeptide 2 in the affected side of the scrotum likely resulted in the characteristics of absent scrotal rugae, and pigmentation on histological and biological analyses. For future fertility, we believe that scrotoplasty should be considered as a management option for hemiscrotal agenesis.
Collapse
Affiliation(s)
- Hidenori Nishio
- Department of Nephro-urology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Kentaro Mizuno
- Department of Nephro-urology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Yoshinobu Moritoki
- Department of Nephro-urology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Hideyuki Kamisawa
- Department of Nephro-urology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Taku Naiki
- Department of Nephro-urology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Satoshi Kurokawa
- Department of Nephro-urology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Akihiro Nakane
- Department of Nephro-urology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Atsushi Okada
- Department of Nephro-urology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Takahiro Yasui
- Department of Nephro-urology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Yutaro Hayashi
- Department of Nephro-urology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| |
Collapse
|
9
|
Ogita A, Funasaka Y, Ansai SI, Kawana S, Saeki H. Melasma in a Male Patient due to Estrogen Therapy for Prostate Cancer. Ann Dermatol 2015; 27:763-4. [PMID: 26719650 PMCID: PMC4695433 DOI: 10.5021/ad.2015.27.6.763] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 01/24/2015] [Accepted: 02/04/2015] [Indexed: 11/08/2022] Open
Affiliation(s)
- Azusa Ogita
- Department of Dermatology, Nippon Medical School Hospital, Tokyo, Japan
| | - Yoko Funasaka
- Department of Dermatology, Nippon Medical School Hospital, Tokyo, Japan
| | - Shin-Ichi Ansai
- Department of Dermatology, Nippon Medical School Hospital, Tokyo, Japan
| | - Seiji Kawana
- Department of Dermatology, Nippon Medical School Hospital, Tokyo, Japan
| | - Hidehisa Saeki
- Department of Dermatology, Nippon Medical School Hospital, Tokyo, Japan
| |
Collapse
|
10
|
Kocarnik JM, Park SL, Han J, Dumitrescu L, Cheng I, Wilkens LR, Schumacher FR, Kolonel L, Carlson CS, Crawford DC, Goodloe RJ, Dilks HH, Baker P, Richardson D, Matise TC, Ambite JL, Song F, Qureshi AA, Zhang M, Duggan D, Hutter C, Hindorff L, Bush WS, Kooperberg C, Le Marchand L, Peters U. Pleiotropic and sex-specific effects of cancer GWAS SNPs on melanoma risk in the population architecture using genomics and epidemiology (PAGE) study. PLoS One 2015; 10:e0120491. [PMID: 25789475 PMCID: PMC4366224 DOI: 10.1371/journal.pone.0120491] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 01/22/2015] [Indexed: 11/19/2022] Open
Abstract
Background Several regions of the genome show pleiotropic associations with multiple cancers. We sought to evaluate whether 181 single-nucleotide polymorphisms previously associated with various cancers in genome-wide association studies were also associated with melanoma risk. Methods We evaluated 2,131 melanoma cases and 20,353 controls from three studies in the Population Architecture using Genomics and Epidemiology (PAGE) study (EAGLE-BioVU, MEC, WHI) and two collaborating studies (HPFS, NHS). Overall and sex-stratified analyses were performed across studies. Results We observed statistically significant associations with melanoma for two lung cancer SNPs in the TERT-CLPTM1L locus (Bonferroni-corrected p<2.8x10-4), replicating known pleiotropic effects at this locus. In sex-stratified analyses, we also observed a potential male-specific association between prostate cancer risk variant rs12418451 and melanoma risk (OR=1.22, p=8.0x10-4). No other variants in our study were associated with melanoma after multiple comparisons adjustment (p>2.8e-4). Conclusions We provide confirmatory evidence of pleiotropic associations with melanoma for two SNPs previously associated with lung cancer, and provide suggestive evidence for a male-specific association with melanoma for prostate cancer variant rs12418451. This SNP is located near TPCN2, an ion transport gene containing SNPs which have been previously associated with hair pigmentation but not melanoma risk. Previous evidence provides biological plausibility for this association, and suggests a complex interplay between ion transport, pigmentation, and melanoma risk that may vary by sex. If confirmed, these pleiotropic relationships may help elucidate shared molecular pathways between cancers and related phenotypes.
Collapse
Affiliation(s)
- Jonathan M. Kocarnik
- Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- * E-mail:
| | - S. Lani Park
- Department of Preventive Medicine, Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America
| | - Jiali Han
- Department of Epidemiology, Richard M. Fairbanks School of Public Health, Melvin and Bren Simon Cancer Center, Indiana University, Indianapolis, Indiana, United States of America
| | - Logan Dumitrescu
- Center for Human Genetics Research, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Iona Cheng
- Cancer Prevention Institute of California, Fremont, California, United States of America
| | - Lynne R. Wilkens
- Epidemiology Program, University of Hawaii Cancer Center, Honolulu, Hawaii, United States of America
| | - Fredrick R. Schumacher
- Department of Preventive Medicine, Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America
| | - Laurence Kolonel
- Epidemiology Program, University of Hawaii Cancer Center, Honolulu, Hawaii, United States of America
| | - Chris S. Carlson
- Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Dana C. Crawford
- Department of Epidemiology, Case Western Reserve University, Cleveland, Ohio, United States of America
- Biostatistics Institute for Computational Biology, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Robert J. Goodloe
- Center for Human Genetics Research, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Holli H. Dilks
- Center for Human Genetics Research, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Paxton Baker
- Center for Human Genetics Research, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Danielle Richardson
- Center for Human Genetics Research, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Tara C. Matise
- Department of Genetics, Rutgers University, Piscataway, New Jersey, United States of America
| | - José Luis Ambite
- Information Sciences Institute, University of Southern California, Marina del Rey, California, United States of America
| | - Fengju Song
- Department of Epidemiology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, People’s Republic of China
- Channing Laboratory, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Abrar A. Qureshi
- Department of Dermatology, Brigham and Women’s Hospital, Boston, Massachusetts, United States of America
| | - Mingfeng Zhang
- Department of Dermatology, Brigham and Women’s Hospital, Boston, Massachusetts, United States of America
| | - David Duggan
- Translational Genomics Research Institute, Phoenix, Arizona, United States of America
| | - Carolyn Hutter
- Epidemiology and Genomics Research Program, Division of Cancer Control and Population Sciences, NCI, NIH, Bethesda, Maryland, United States of America
| | - Lucia Hindorff
- Division of Genomic Medicine, NHGRI, NIH, Bethesda, Maryland, Untied States of America
| | - William S. Bush
- Center for Human Genetics Research, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Biomedical Informatics, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Charles Kooperberg
- Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Loic Le Marchand
- Epidemiology Program, University of Hawaii Cancer Center, Honolulu, Hawaii, United States of America
| | - Ulrike Peters
- Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| |
Collapse
|
11
|
Kocarnik JM, Park SL, Han J, Dumitrescu L, Cheng I, Wilkens LR, Schumacher FR, Kolonel L, Carlson CS, Crawford DC, Goodloe RJ, Dilks H, Baker P, Richardson D, Ambite JL, Song F, Quresh AA, Zhang M, Duggan D, Hutter C, Hindorff LA, Bush WS, Kooperberg C, Le Marchand L, Peters U. Replication of associations between GWAS SNPs and melanoma risk in the Population Architecture Using Genomics and Epidemiology (PAGE) Study. J Invest Dermatol 2014; 134:2049-2052. [PMID: 24480881 PMCID: PMC4057959 DOI: 10.1038/jid.2014.53] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Jonathan M Kocarnik
- Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.
| | - Sungshim Lani Park
- Epidemiology Program, University of Hawaii Cancer Center, Honolulu, Hawaii, USA
| | - Jiali Han
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA; Department of Epidemiology, Fairbanks School of Public Health, Simon Cancer Center, Indiana University, Indianapolis, Indiana, USA
| | - Logan Dumitrescu
- Center for Human Genetics Research, Vanderbilt University, Nashville, Tennessee, USA; Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA
| | - Iona Cheng
- Cancer Prevention Institute of California, Fremont, California, USA
| | - Lynne R Wilkens
- Epidemiology Program, University of Hawaii Cancer Center, Honolulu, Hawaii, USA
| | - Fredrick R Schumacher
- Department of Preventive Medicine, Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Laurence Kolonel
- Epidemiology Program, University of Hawaii Cancer Center, Honolulu, Hawaii, USA
| | - Chris S Carlson
- Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Dana C Crawford
- Center for Human Genetics Research, Vanderbilt University, Nashville, Tennessee, USA; Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA
| | - Robert J Goodloe
- Center for Human Genetics Research, Vanderbilt University, Nashville, Tennessee, USA
| | - Holli Dilks
- Center for Human Genetics Research, Vanderbilt University, Nashville, Tennessee, USA
| | - Paxton Baker
- Center for Human Genetics Research, Vanderbilt University, Nashville, Tennessee, USA
| | - Danielle Richardson
- Center for Human Genetics Research, Vanderbilt University, Nashville, Tennessee, USA
| | - José Luis Ambite
- Information Sciences Institute, University of Southern California, Marina del Rey, California, USA
| | - Fengju Song
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA; Department of Epidemiology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Abrar A Quresh
- Department of Dermatology, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Mingfeng Zhang
- Department of Dermatology, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - David Duggan
- Translational Genomics Research Institute, Phoenix, Arizona, USA
| | - Carolyn Hutter
- Epidemiology and Genomics Research Program, Division of Cancer Control and Population Sciences, NCI, NIH, Bethesda, Maryland, USA
| | - Lucia A Hindorff
- Division of Genomic Medicine, NHGRI, NIH, Bethesda, Maryland, USA
| | - William S Bush
- Center for Human Genetics Research, Vanderbilt University, Nashville, Tennessee, USA; Department of Biomedical Informatics, Vanderbilt University, Nashville, Tennessee, USA
| | - Charles Kooperberg
- Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Loic Le Marchand
- Epidemiology Program, University of Hawaii Cancer Center, Honolulu, Hawaii, USA
| | - Ulrike Peters
- Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.
| |
Collapse
|
12
|
Castillo-Briceno P, Kodjabachian L. Xenopus embryonic epidermis as a mucociliary cellular ecosystem to assess the effect of sex hormones in a non-reproductive context. Front Zool 2014; 11:9. [PMID: 24502321 PMCID: PMC4015847 DOI: 10.1186/1742-9994-11-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Accepted: 01/28/2014] [Indexed: 12/15/2022] Open
Abstract
Background How important are sexual hormones beyond their function in reproductive biology has yet to be understood. In this study, we analyzed the effects of sex steroids on the biology of the embryonic amphibian epidermis, which represents an easily amenable model of non-reproductive mucociliary epithelia (MCE). MCE are integrated systems formed by multiciliated (MC), mucus-secreting (MS) and mitochondrion-rich (MR) cell populations that are shaped by their microenvironment. Therefore, MCE could be considered as ecosystems at the cellular scale, found in a wide array of contexts from mussel gills to mammalian oviduct. Results We showed that the natural estrogen (estradiol, E2) and androgen (testosterone, T) as well as the synthetic estrogen (ethinyl-estradiol, EE2), all induced a significant enhancement of MC cell numbers. The effect of E2, T and EE2 extended to the MS and MR cell populations, to varying degrees. They also modified the expression profile of RNA MCE markers, and induced a range of “non-typical” cellular phenotypes, with mixed identities and aberrant morphologies, as revealed by imaging analysis through biomarker confocal detection and scanning electron microscopy. Finally, these hormones also affected tadpole pigmentation, revealing an effect on the entire cellular ecosystem of the Xenopus embryonic skin. Conclusions This study reveals the impact in vivo, at the molecular, cellular, tissue and organism levels, of sex steroids on non-reproductive mucociliary epithelium biogenesis, and validates the use of Xenopus as a relevant model system in this field.
Collapse
Affiliation(s)
- Patricia Castillo-Briceno
- Aix-Marseille Université, CNRS UMR 7288, IBDM, Campus de Luminy Case 907, 13288 Marseille Cedex 9, France.
| | | |
Collapse
|
13
|
Seleit I, Bakry OA, Abdou AG, Dawoud NM. Immunohistochemical study of melanocyte-melanocyte stem cell lineage in vitiligo; a clue to interfollicular melanocyte stem cell reservoir. Ultrastruct Pathol 2014; 38:186-98. [PMID: 24460782 DOI: 10.3109/01913123.2013.870274] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
There has been a long lasting controversy over whether melanocytes (MCs) in vitiligo are actually lost or still present but functionally inactive. We aimed to evaluate the MC cell lineage in follicular and interfollicular vitiliginous epidermis through immunohistochemical localization of Human Melanoma Black-45 (HMB-45) and Tyrosinase Related Protein 2 (TRP2) and to correlate it with clinicopathologic parameters. Using immunohistochemical techniques, skin biopsies from 50 vitiligo patients and 20 age- and gender-matched healthy subjects were examined. Differentiated active MCs were detected in 44% of interfollicular epidermis (IFE) and 46.7% of follicular epidermis (FE) in lesional skin. Melanocyte precursors/stem cells were detected in 54% of IFE and 63.3% of FE in lesional skin. Melanocyte precursors/stem cells of IFE were significantly associated with residual melanin pigment (p = 0.007) and with absence of angiogenesis (p = 0.05). HMB-45 percentage of expression in IFE was positively correlated with MC precursors/stem cells percentage in FE (r = +0.65, p < 0.001) and IFE (r = +0.33, p = 0.01). Melanocyte precursors/stem cells positivity (p < 0.001) was progressively decreasing with advanced histopathologic grading. There was no significant association between interfollicular or follicular expression of HMB-45, TRP2 or MC precursors/stem cells and the clinical type of vitiligo or its duration. In conclusion, functioning MCs may exist in vitiligo. The presence of MC precursors/stem cells in IFE may provide an additional reservoir needed for repigmentation.
Collapse
Affiliation(s)
- Iman Seleit
- Department of Dermatology, Andrology and STDs and
| | | | | | | |
Collapse
|
14
|
Chang TS, Lin JJ. Inhibitory effect of danazol on melanogenesis in mouse B16 melanoma cells. Arch Pharm Res 2010; 33:1959-65. [PMID: 21191761 DOI: 10.1007/s12272-010-1211-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Revised: 05/01/2010] [Accepted: 05/02/2010] [Indexed: 10/18/2022]
Abstract
In the present study, more than 200 generic drugs were screened to verify their applicability as a skin-lightening agent using mouse B16 melanoma cells. Of the numerous agents, danazol was found to inhibit melanogenesis in B16 cells in a dose-dependent manner with an IC(50) value of 9.3 μM. In addition, danazol reduced cellular tyrosinase activity in B16 cells but did not directly inhibit the murine tyrosinase activity in the cell-free system. Western blotting analysis confirmed that danazol downregulated the levels of tyrosinase protein in B16 cells, and reverse-transcription polymerase chain reaction (RT-PCR) analysis revealed that danazol did not downregulate the levels of tyrosinase mRNA in the cells. These results indicate that danazol inhibits melanogenesis in B16 cells via reducing the tyrosinase activity by post-transcriptional regulation.
Collapse
Affiliation(s)
- Te-Sheng Chang
- Department of Biological Science and Technology, National University of Tainan, Tainan 700, Taiwan.
| | | |
Collapse
|
15
|
Kim YJ, Han JH, Kang HY, Lee ES, Kim YC. Androgen receptor overexpression in Becker nevus: histopathologic and immunohistochemical analysis. J Cutan Pathol 2009; 35:1121-6. [PMID: 18616760 DOI: 10.1111/j.1600-0560.2008.00988.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Becker nevus (BN) is a unilateral, hairy, pigmented cutaneous hamartoma that frequently appears in adolescence. Several features of BN suggest that increased androgen sensitivity plays a role in its pathogenesis. There have been only a few studies of histopathologic and immunohistochemical characteristics of BN, and the etiopathogenesis has not been fully established. METHODS Two-millimeter punch biopsies were taken from lesional and perilesional normal skin of 30 patients diagnosed as having BN. Fifteen skin samples each of lentigo and café au lait spots were used as controls. The sections were stained with hematoxylin-eosin, Fontana-Masson, antibodies to NKI/beteb, MART-1 (Melanoma Antigen Recognized by T cells), S-100 protein and androgen receptor (AR). RESULTS Histopathologic features of BN showed frequent acanthosis, papillomatosis, keratotic plugging, irregular rete ridge elongation and flattening in the epidermis. Especially, the shape of the rete ridges in BN had a relatively characteristic appearance, which was the fusion of more than two adjacent rete ridges. Melanocyte counts were significantly increased in BN skin. The extent of AR expression was significantly higher in the epidermis of BN. CONCLUSIONS Our study indicates that there may be an association between AR and BN, but additional studies will be required to evaluate this further.
Collapse
Affiliation(s)
- Young Jin Kim
- Department of Dermatology, Ajou University School of Medicine, Suwon, Korea
| | | | | | | | | |
Collapse
|
16
|
Abstract
More than 150 genes have been identified that affect skin color either directly or indirectly, and we review current understanding of physiological factors that regulate skin pigmentation. We focus on melanosome biogenesis, transport and transfer, melanogenic regulators in melanocytes, and factors derived from keratinocytes, fibroblasts, endothelial cells, hormones, inflammatory cells, and nerves. Enzymatic components of melanosomes include tyrosinase, tyrosinase-related protein 1, and dopachrome tautomerase, which depend on the functions of OA1, P, MATP, ATP7A, and BLOC-1 to synthesize eumelanins and pheomelanins. The main structural component of melanosomes is Pmel17/gp100/Silv, whose sorting involves adaptor protein 1A (AP1A), AP1B, AP2, and spectrin, as well as a chaperone-like component, MART-1. During their maturation, melanosomes move from the perinuclear area toward the plasma membrane. Microtubules, dynein, kinesin, actin filaments, Rab27a, melanophilin, myosin Va, and Slp2-a are involved in melanosome transport. Foxn1 and p53 up-regulate skin pigmentation via bFGF and POMC derivatives including alpha-MSH and ACTH, respectively. Other critical factors that affect skin pigmentation include MC1R, CREB, ASP, MITF, PAX3, SOX9/10, LEF-1/TCF, PAR-2, DKK1, SCF, HGF, GM-CSF, endothelin-1, prostaglandins, leukotrienes, thromboxanes, neurotrophins, and neuropeptides. UV radiation up-regulates most factors that increase melanogenesis. Further studies will elucidate the currently unknown functions of many other pigment genes/proteins. (c) 2009 International Union of Biochemistry and Molecular Biology, Inc.
Collapse
Affiliation(s)
- Yuji Yamaguchi
- Department of Geriatric and Environmental Dermatology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
| | | |
Collapse
|
17
|
Freedman ND, Ahn J, Hou L, Lissowska J, Zatonski W, Yeager M, Chanock SJ, Chow WH, Abnet CC. Polymorphisms in estrogen- and androgen-metabolizing genes and the risk of gastric cancer. Carcinogenesis 2008; 30:71-7. [PMID: 19015200 DOI: 10.1093/carcin/bgn258] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Androgens and estrogens may play a role in gastric cancer etiology. To investigate the association of gastric cancer with single-nucleotide polymorphisms (SNPs) in six genes (COMT, CYP1B1, CYP17A1, CYP19A1, HSD17B1 and SHBG) involved in estrogen and androgen synthesis and metabolism, 58 haplotype-tagging SNPs were genotyped in 295 gastric cancer cases and 415 controls from a population-based study in Poland. We assessed differences in haplotype frequency between cases and controls using a global score test and calculated multivariate odds ratios (ORs) and 95% confidence intervals (CIs) for individual haplotypes using logistic regression. We found associations in one linkage disequilibrium (LD) block containing the 3' untranslated region of COMT (rs9332377, rs165728, rs165849 and rs1110478), global score test (df = 4, P = 0.033). Relative to the most frequent GATA haplotype, the GATG haplotype was associated with statistically significant increased gastric cancer risk (OR = 1.50, 95% CI: 1.06-2.12; false discovery rate (FDR) value = 0.459) and the AACA haplotype with borderline increased risk (OR = 1.36, 95% CI = 1.00-1.85; FDR = 0.50). We also found associations for the LD block containing part of the SHBG coding region (rs6258, rs6259, rs2955617, rs1641544 and rs1641537). The CACCC haplotype was associated with statistically significant lower gastric cancer risk relative to the referent CGACC haplotype (OR = 0.55, 95% CI = 0.34-0.90; FDR = 0.459), but the overall score test was statistically non-significant. No other statistically significant associations were observed. In summary, we found possible associations between gastric cancer and polymorphisms in COMT, involved in estrogen inactivation, and SHBG, a modulator of hormone bioavailability. These findings should be interpreted cautiously until replicated in other studies.
Collapse
Affiliation(s)
- Neal D Freedman
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Rockville, MD 20852, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Abstract
All organisms, from simple invertebrates to complex human beings, exist in different colors and patterns, which arise from the unique distribution of pigments throughout the body. Pigmentation is highly heritable, being regulated by genetic, environmental, and endocrine factors that modulate the amount, type, and distribution of melanins in the skin, hair, and eyes. In addition to its roles in camouflage, heat regulation, and cosmetic variation, melanin protects against UV radiation and thus is an important defense system in human skin against harmful factors. Being the largest organ of the body that is always under the influence of internal and external factors, the skin often reacts to those agents by modifying the constitutive pigmentation pattern. The focus of this review is to provide an updated overview of important physiological and biological factors that increase pigmentation and the mechanisms by which they do so. We consider endocrine factors that induce temporary (e.g., during pregnancy) or permanent (e.g., during aging) changes in skin color, environmental factors (e.g., UV), certain drugs, and chemical compounds, etc. Understanding the mechanisms by which different factors and compounds induce melanogenesis is of great interest pharmaceutically (as therapy for pigmentary diseases) and cosmeceutically (e.g., to design tanning products with potential to reduce skin cancer risk).
Collapse
Affiliation(s)
- Gertrude-E Costin
- Avon Products, Inc., New Technology Department, 1 Avon Pl., Suffern, NY 10901, USA.
| | | |
Collapse
|
19
|
Solano F, Briganti S, Picardo M, Ghanem G. Hypopigmenting agents: an updated review on biological, chemical and clinical aspects. ACTA ACUST UNITED AC 2007; 19:550-71. [PMID: 17083484 DOI: 10.1111/j.1600-0749.2006.00334.x] [Citation(s) in RCA: 459] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
An overview of agents causing hypopigmentation in human skin is presented. The review is organized to put forward groups of biological and chemical agents. Their mechanisms of action cover (i) tyrosinase inhibition, maturation and enhancement of its degradation; (ii) Mitf inhibition; (iii) downregulation of MC1R activity; (iv) interference with melanosome maturation and transfer; (v) melanocyte loss, desquamation and chemical peeling. Tyrosinase inhibition is the most common approach to achieve skin hypopigmentation as this enzyme catalyses the rate-limiting step of pigmentation. Despite the large number of tyrosinase inhibitors in vitro, only a few are able to induce effects in clinical trials. The gap between in-vitro and in-vivo studies suggests that innovative strategies are needed for validating their efficacy and safety. Successful treatments need the combination of two or more agents acting on different mechanisms to achieve a synergistic effect. In addition to tyrosinase inhibition, other parameters related to cytotoxicity, solubility, cutaneous absorption, penetration and stability of the agents should be considered. The screening test system is also very important as keratinocytes play an active role in modulating melanogenesis within melanocytes. Mammalian skin or at least keratinocytes/melanocytes co-cultures should be preferred rather than pure melanocyte cultures or soluble tyrosinase.
Collapse
Affiliation(s)
- Francisco Solano
- Department of Biochemistry and Molecular Biology B, University of Murcia, Murcia, Spain.
| | | | | | | |
Collapse
|
20
|
Abstract
Estrogens have a profound influence on skin. The relative hypoestrogenism that accompanies menopause exacerbates the deleterious effects of both intrinsic and environmental aging. Estrogens clearly have a key role in skin aging homeostasis as evidenced by the accelerated decline in skin appearance seen in the perimenopausal years. Estrogens improve skin in many ways. Among these, they increase collagen content and skin thickness and improve skin moisture. However, despite the knowledge that estrogens have such important effects on skin, the cellular and subcellular sites and mechanisms of estrogen action are still poorly understood. Estrogen receptors (ERs) have been detected in skin, and recent studies suggest that estrogens exert their effect in skin through the same molecular pathways used in other non-reproductive tissues. Although systemic hormone replacement therapy (HRT) has been used for many years, recent trials have reported a significant increased risk of breast cancer and other pathologies with this treatment. This has led to reconsider the risks and benefits of HRT. For this reason, systemic HRT cannot be recommended today to treat skin aging. Currently, intensive research is conducted to develop new drugs called selective ER modulators (SERMs). These drugs exert mixed estrogenic and antiestrogenic effects depending on the tissue and cell type. One might expect in the future such a drug targeting specifically the skin without systemic side effects.
Collapse
|