- The Anti-melanogenesis Activities of Some Selected Red Macroalgae from Northern Coasts of the Persian Gulf. [Journal Article]
- IJIran J Pharm Res 2019; 18(1):383-390
- Tyrosinase is a key enzyme in melanin production. Therefore, tyrosinase inhibitors are used in cosmetic and medicinal industries to prevent or treat overproduction of melanin such as melasma, solar l…
Tyrosinase is a key enzyme in melanin production. Therefore, tyrosinase inhibitors are used in cosmetic and medicinal industries to prevent or treat overproduction of melanin such as melasma, solar lentigo and post inflammatory melanoderma. Due to safety of natural whitening agents, in the present study, in-vitro anti-tyrosinase and in-vivo anti-melanogenesis activities of some selected red macroalgae of the Persian Gulf were investigated. The effects of various concentrations (100, 250 and 500 µg/mL) of methanolic extracts of three red macroalgae including Digenea simplex (D. simplex), Laurencia papillosa, and Laurencia paniculata on the activity of diphenolase of mushroom tyrosinase were studied by using L-Dopa as substrate. Subsequently, the activity of macroalgae with high inhibitory effect on hydroxylation of L-tyrosine was investigated by mushroom tyrosinase and zebrafish model. Anti-melanogenesis effects of algae extracts were studied on zebrafish as an alternative in-vivo model. Kojic acid was used as a positive control. All the tested macroalgae showed significantly a lower inhibitory effect on activities of diphenolase and monophenolase (of mushroom tyrosinase) compared to kojic acid. D. simplex showed the most anti-tyrosinase activity in zebrafish model among the samples. D. simplex extract and Kojic acid inhibited tyrosinase activity by 43.18% and 50.45%, and decreased total melanin content of zebrafish by 47.27% and 50.21%, respectively.
- The Inhibition of Melanogenesis Via the PKA and ERK Signaling Pathways by Chlamydomonas reinhardtii Extract in B16F10 Melanoma Cells and Artificial Human Skin Equivalents. [Journal Article]
- JMJ Microbiol Biotechnol 2018 Dec 28; 28(12):2121-2132
- Abnormal melanin synthesis results in several hyperpigmentary disorders such as freckles, melanoderma, age spots, and other related conditions. In this study, we investigated the antimelanogenic effe…
Abnormal melanin synthesis results in several hyperpigmentary disorders such as freckles, melanoderma, age spots, and other related conditions. In this study, we investigated the antimelanogenic effects of an extract from the microalgae Chlamydomonas reinhardtii (CE) and potential mechanisms responsible for its inhibitory effect in B16F10, normal human epidermal melanocyte cells, and human skin-equivalent models. The CE extract showed significant dose-dependent inhibitory effects on α-melanocyte-stimulating, hormone-induced melanin synthesis in cells. Additionally, the CE extract exhibited suppressive effects on the mRNA and protein expression of microphthalmia-associated transcription factor, tyrosinase, tyrosinase-related protein-1, and tyrosinase-related protein-2. The CE extract also inhibited the phosphorylation of protein kinase A and extracellular signal-related kinase, which function as upstream regulators of melanogenesis. Using a three-dimensional, reconstructed pigmented epidermis model, the CE-mediated, anti-pigmentation effects were confirmed by Fontana-Masson staining and melanin content assays. Taken together, CE extract can be used as an anti-pigmentation agent.
- [Epidemiological and clinical profile of skin damages in black African patients on chronic hemodialysis]. [Journal Article]
- PAPan Afr Med J 2016; 25:142
- CONCLUSIONS: Skin damages are frequent and dominated by xerosis, pruritus and melanoderma in patients on chronic hemodialysis living in Yaounde. Biweekly dialysis, advanced age, anuria and time spent on dialysis were associated factors.
- Immunotactoid glomerulopathy leading to the discovery of POEMS syndrome . [Case Reports]
- CNClin Nephrol 2017; 87(6):310-315
- Monoclonal gammopathy of renal significance (MGRS) can manifest in many different ways depending on the nature of the immunoglobulin and its physicochemical properties. MGRS can lead to the discovery…
Monoclonal gammopathy of renal significance (MGRS) can manifest in many different ways depending on the nature of the immunoglobulin and its physicochemical properties. MGRS can lead to the discovery of a hematological malignancy. We report the case of a 32-year-old female patient who underwent renal biopsy on account of an impure nephrotic syndrome associated with immunoglobulin (Ig)G κ monoclonal gammopathy. Histological analysis revealed membranoproliferative glomerulonephritis with IgG, IgM, κ, λ, and C3 deposits. Due to an unfavorable progression, a second renal biopsy was performed. Electron microscopy analysis revealed an immunotactoid glomerulopathy. At the same time, a POEMS syndrome diagnosis (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin abnormalities) was confirmed in light of the following: 1) IgG κ monoclonal gammopathy, 2) axonal neuropathy, 3) osteosclerosis, 4) melanoderma, 5) hepatosplenomegaly and adenopathies, 6) Castleman disease, and 7) edema. Our observation is the first case of immunotactoid glomerulopathy leading to the discovery of a POEMS syndrome. Renal involvement in POEMS syndrome typically exhibits a thrombotic microangiopathy-like membranoproliferative glomerulonephritis appearance associated with endothelial lesions stigmata. However, monoclonal immunoglobulin deposition disorder should be considered in the event of an atypical case. In this indication, electron microscopy is the examination of choice for assessing immunoglobulin deposition nephropathy. .
- Melanoderma: uncommon presentation of a common condition. [Case Reports]
- BCBMJ Case Rep 2016 Dec 20; 2016
- A 64-year-old man presented with blackish pigmentation of skin and tongue for more than 2 years that did not improve with local remedies. He had no history of comorbid medical or surgical illnesses. …
A 64-year-old man presented with blackish pigmentation of skin and tongue for more than 2 years that did not improve with local remedies. He had no history of comorbid medical or surgical illnesses. General examination showed severe hyperpigmentation of skin and mucosa and also showed anaemia. Systemic examination was unremarkable except for Romberg sign and mild hyperreflexia. Adrenal insufficiency was ruled out by normal cortisol levels and haemogram showed macrocytosis with hypersegmented neutrophils suggestive of severe vitamin B12 deficiency which confirmed by low serum B12 levels. After 3 months of parenteral vitamin B12 treatment, the pigmentation and anaemia improved significantly. The mechanism of hyperpigmentation due to B12 deficiency is postulated to be increased melanin deposition in the basal layer of the epidermis. Since vitamin B12 deficiency is not uncommonly encountered in general practice, atypical presentation of this easily diagnosable and treatable condition is emphasised.
- Pagetoid Spitz nevi: clinicopathologic characterization of a series of 12 cases. [Journal Article]
- JCJ Cutan Pathol 2016; 43(11):932-939
- CONCLUSIONS: This represents the largest series of pagetoid Spitz nevi characterized to date. Although most clinicopathologic characteristics in our series correlated with those previously described, novel findings included occurrence in middle-aged adults, occurrence above the waist and demonstration of melanoderma in all lesions. Presence of dermal inflammation and melanoderma may contribute to atypical clinical appearance leading to biopsy despite their small clinical size. Recognition of these additional novel histologic features may aid dermatopathologists in distinguishing pagetoid Spitz nevi from melanoma.
- Diagnosis: Melanoderma after Hematopoietic Stem Cell Transplantation. [Case Reports]
- TJTurk J Haematol 2015; 32(4):378-9
- [Allgrove syndrome]. [Case Reports]
- ADAnn Dermatol Venereol 2015; 142(2):121-4
- CONCLUSIONS: The present case serves as a reminder that Allgrove syndrome may be diagnosed by dermatologists. Therapy is cross-disciplinary, being based upon medical treatment for adrenal insufficiency with prescription of artificial tears in the event of alacrima. Achalasia is treated by oesophageal dilatation or by surgery.
- In vivo skin fluorescence imaging in young Caucasian adults with early malignant melanomas. [Journal Article]
- CCClin Cosmet Investig Dermatol 2014; 7:225-30
- CONCLUSIONS: Thin CMM supervening in young women appear unrelated to repeat photoexposure. Other mechanisms are possibly involved.
New Search Next
- Novel inhibitory effect of N-(2-hydroxycyclohexyl)valiolamine on melanin production in a human skin model. [Journal Article]
- IJInt J Mol Sci 2014 Jul 09; 15(7):12188-95
- Hyper-pigmentation causes skin darkness and medical disorders, such as post-inflammatory melanoderma and melasma. Therefore, the development of anti-melanogenic agents is important for treating these…
Hyper-pigmentation causes skin darkness and medical disorders, such as post-inflammatory melanoderma and melasma. Therefore, the development of anti-melanogenic agents is important for treating these conditions and for cosmetic production. In our previous paper, we demonstrated that the anti-diabetic drug voglibose, a valiolamine derivative, is a potent anti-melanogenic agent. In addition, we proposed an alternative screening strategy to identify valiolamine derivatives with high skin permeability that act as anti-melanogenic agents when applied topically. In this study, we synthesized several valiolamine derivatives with enhanced lipophilicity and examined their inhibitory effects in a human skin model. N-(2-hydroxycyclohexyl)valiolamine (HV) possesses a stronger inhibitory effect on melanin production than voglibose in a human skin model, suggesting that HV is a more potent anti-melanogenic agent for the skin.