Nigella sativa seed extract and its bioactive compound thymoquinone: the new melanogens causing hyperpigmentation in the wall lizard melanophores

Dermaceutical Utilization of Nigella sativa Seeds: Applications and Opportunities

Skin diseases have recently become a major concern among people of all ages due to their highly visible symptoms and persistent and difficult treatment, which significantly impact their quality of life. Nigella sativa seeds, also known as "black seeds" or "kalonji," are one of the most commonly used herbal medicines due to their wide range of biological and pharmacological activities. It contains a wide range of bioactive constituents found in both fixed and essential oils. It has been used for hundreds of years as an alternative ethnomedicine to treat a wide range of skin conditions. N. sativa's dermatological applications in skin diseases are attributed to its potent antioxidant, anti-inflammatory, antimicrobial, and immunomodulatory properties, making it an intriguing skincare candidate. Several studies unravelled positive results associated with N. sativa on skin diseases. As N. sativa is the most studied medicinal plant, several preclinical and clinical studies have been conducted to establish its use in the treatment of various skin diseases. Thymoquinone has anti-inflammatory, antioxidant, and antibacterial properties, which mainly contributed to the treatment of skin diseases. In this context, the present review explores all the available studies on the association of N. sativa and its effect on treating skin diseases in light of recent studies and patents supporting its therapeutic applications.

Research Progress of Small Molecules as Anti-vitiligo Agents

Vitiligo is a disease characterized by skin discoloration, and no safe and effective drugs have been developed until now. New drug research and development are imminent. This article reviews the research on small-molecule drugs for vitiligo from 1990 to 2021 at home and abroad. They are classified according to their structures and mechanisms of action, including natural products and derivatives, anti-oxidative stress drugs, immunosuppressants, prostaglandins, etc. The research on their anti-vitiligo activity, structural modification, new dosage forms, clinical trials, and the development trend in new anti-vitiligo drugs are reviewed, which provides important references for the development of new drugs.

The Therapeutic Effects of Nigella sativa on Skin Disease: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

The aim of this systematic review was to identify randomized controlled trials that looked at the effects of Nigella sativa in any form on different skin diseases. Up to March 2022, the online databases of Scopus, Web of Science, PubMed, Embase, Google Scholar, and Cochrane trials were searched. This study included 14 records of people who had experienced different types of skin disease including atopic dermatitis, vulgaris, arsenical keratosis, psoriasis, vitiligo, acute cutaneous leishmaniasis, warts, eczema, and acne. The mean SD age of the patients was 28.86 (4.49); [range: 18.3-51.4], with females accounting for 69% (506 out of 732) of the total. The follow-up mean SD was 8.16 (1.3) (ranged: 4 days to 24 weeks). The odds ratio (OR) was found to be 4.59 in a meta-analysis (95% CI: 2.02, 10.39). Whereas the null hypothesis in this systematic review was that lotion had no impact, OR 4.59 indicated that lotion could be effective. The efficacy of N. sativa essential oil and extract has been demonstrated in most clinical studies. However, more research is needed to completely evaluate and validate the efficacy or inadequacy of therapy with N. sativa, although it appears that it can be used as an alternative treatment to help people cope with skin problems.

Role of Amine Neurotransmitters and Their Receptors in Skin Pigmentation: Therapeutic Implication

Skin pigmentation can occur due to increased melanin, including melanocyte proliferation, melanin biosynthesis, or melanocyte migration. There are many factors that influence the melanin production process, but the role of neurotransmitters in this process is still unclear. We found that histamine and serotonin influence the different stages of melanogenesis and melanogenesis, which increase melanogenesis. Since then, several related papers have been published, and from these papers, it has been recognised that the role of neurotransmitters in skin-pigment-related diseases needs to be summarised. By introducing the role of neurotransmitters in the regulation of various pigment disorders, including vitiligo and melasma, through this review, many researchers can be expected to try to apply neurotransmitter-related agonists and antagonists as treatments for skin pigment disorders.

A review of Nigella sativa plant-based therapy in dermatology

Nigella sativa (N. sativa) is a widely used medicinal herb with a rich cultural and religious history in Unani, Ayurveda, Chinese, and Arabic medicine. N. sativa contains many natural bioactive agents including alkaloids, saponins, alpha-hederin, and thymoquinone that contribute to its broad range of benefits as a diuretic, bronchodilator, antihypertensive, antidiabetic, and analgesic. In addition, N. sativa possesses antimicrobial, anti-inflammatory, and antineoplastic effects, making it an interesting potential therapy for the treatment of dermatological conditions. This article reviews the current literature surrounding the pharmacological effects of N. sativa for the treatment of acne vulgaris, melanoma, vitiligo, atopic dermatitis, plaque psoriasis, and wound healing.

Oxidative stress and the cholinergic system in non-segmental vitiligo: Effect of narrow band ultraviolet b

BACKGROUND

Despite exhaustive research, melanocyte disappearance and the evolution of vitiligo remain enigmatic, and although multi-factorial, oxidative stress appears as a major player. The role of cutaneous cholinergic system in vitiligo pathogenesis has also been reported in some studies.

OBJECTIVE

To evaluate and correlate the influence of phototherapy on cutaneous cholinergic system and oxidative stress in vitiligo.

METHODS

Acetyl choline (ACh), its receptors; nicotinic (nAChR) and muscarinic (mAChR); acetylcholine esterase (AChE) and H₂ O₂ levels were estimated in de-pigmented and re-pigmented lesions of 30 vitiligo patients before and after NB-UVB phototherapy and in 30 controls. ACh and H₂ O₂ levels were measured by colorimetry. AChE and acetylcholine receptors expression were measured by quantitative real-time PCR.

RESULTS

Mean ACh and H₂ O₂ levels were significantly higher in vitiligo lesions before NB-UVB (P < .001) whereas AChE enzyme level was significantly lower (P < .001) compared to both re-pigmented and control skin. Additionally, mean mAChR was significantly higher and mean nAChR was significantly lower in vitiligo lesions before NB-UVB versus controls and re-pigmented skin (P < .001). Also, H₂ O₂ and AChE showed negative correlation whereas ACh and mAChR showed significant positive correlation. Although all the studied parameters showed significant changes after treatment and subsequent re-pigmentation, a significant difference continued to exist between all vitiligo skin and controls.

CONCLUSION

Cholinergic system is strongly involved in vitiligo pathogenesis through H₂ O₂ inhibition of AChE which could be reversed by NB-UVB. Moreover, the strong activation of mAChRs may reflect genetic and/or acquired errors, direct up-regulation by ACh and H₂ O₂ or both.

Thymocid®, a Standardized Black Cumin (Nigella sativa) Seed Extract, Modulates Collagen Cross-Linking, Collagenase and Elastase Activities, and Melanogenesis in Murine B16F10 Melanoma Cells

Black cumin (Nigella sativa) seed extract has been shown to improve dermatological conditions, yet its beneficial effects for skin are not fully elucidated. Herein, Thymocid®, a chemically standardized black cumin seed extract, was investigated for its cosmeceutical potential including anti-aging properties associated with modulation of glycation, collagen cross-linking, and collagenase and elastase activities, as well as antimelanogenic effect in murine melanoma B16F10 cells. Thymocid® (50, 100, and 300 µg/mL) inhibited the formation of advanced glycation end-products (by 16.7-70.7%), collagen cross-linking (by 45.1-93.3%), collagenase activity (by 10.4-92.4%), and elastases activities (type I and III by 25.3-75.4% and 36.0-91.1%, respectively). In addition, Thymocid® (2.5-20 µg/mL) decreased melanin content in B16F10 cells by 42.5-61.6% and reduced cellular tyrosinase activity by 20.9% (at 20 µg/mL). Furthermore, Thymocid® (20 µg/mL for 72 h) markedly suppressed the mRNA expression levels of melanogenesis-related genes including microphthalmia-associated transcription factor (MITF), tyrosinase-related protein 1 (TYRP1), and TYRP2 to 78.9%, 0.3%, and 0.2%, respectively. Thymocid® (10 µg/mL) also suppressed the protein expression levels of MITF (by 15.2%) and TYRP1 (by 97.7%). Findings from this study support the anti-aging and antimelanogenic potential of Thymocid® as a bioactive cosmeceutical ingredient for skin care products.

The effect of nigella sativa oil on the prevention of phlebitis induced by chemotherapy: a clinical trial

Introduction: Phlebitis, that disrupts chemotherapy, is the inflammation of the vein and the most common complication of intravenous injection of chemotherapy drugs.

Aim: the aim was determine the effect of topical application of N. sativa oil on the prevention of phlebitis caused by chemotherapy.

Methods: This single-blind clinical trial was conducted on 60 cancer patients. In the intervention group, five drops of N. sativa oil was applied on the distal area of the catheter, two times per day and every 12 hours from the first day of chemotherapy to the third day; no intervention was conducted for the subjects in the control group.

Results: Results showed that there was a significant difference between the two groups at 60 and 72 hours in regard with incidence of phlebitis. There was a statistically significant difference between the two groups at 12 and 72 hours in terms of severity (degree) of phlebitis.

Conclusion: topical application of N. sativa oil is effective in the prevention of chemotherapy-induced phlebitis.

Effectiveness of topical Nigella sativa for vitiligo treatment

Vitiligo is a pigment disease characterized by the disruption of melanocyte structure and function. Its etiology is unknown; however, genetic predisposition, biochemical factors, and neural mechanisms are thought to be effective. Although many agents are being used for its treatment, generally there is no absolute cure. The aim of the present study is to evaluate the effectiveness of topical Nigella sativa seed oil on vitiligo patients. Thirty-three vitiligo patients were included in the study. Totally 47 areas were evaluated in all patients. Cream containing N sativa seed oil was topically applied to hands, face, and genital region two times a day for 6 months. Statistically significant repigmentation was detected in hands, face, and genital region, the three treatment areas, and the p values are found .005, .001, and .004, respectively. N sativa can be used as an adjuvant therapy that can contribute to the treatment especially in sensitive skin areas like genital region.

A Review on the Cosmeceutical and External Applications of Nigella sativa

It is estimated by the World Health Organization (WHO) that most of the world's population depends on herbal medicine for their health care. Nigella sativa (N. sativa), also known as black-caraway and as “Kalonji,” is a well-known seed all over the world. It is one of the most common medicinal plants worldwide and contains many useful chemical constituents that we can find in its fixed oil, such as thymoquinone, thymohydroquinone, dithymoquinone, thymol, nigellicine, carvacrol, nigellimine, nigellicine, nigellidine, and alpha-hederin. Due to these numerous important ingredients it was found that it affects different areas of our body and has many pharmacological effects as antibacterial, antiviral, anti-inflammatory, and wound healing effect and also for acne vulgaris, skin cancer, pigmentation, and many cosmeceutical applications. Based on the folklore usage of N. sativa seeds and oil, they are used in various systems of food and medicines. The aim of this article is to provide a detailed survey of the literature of cosmeceutical and external applications of N. sativa which is expected to stimulate further studies on this subject.

Quantifying pigment cover to assess variation in animal colouration

The study of animal colouration addresses fundamental and applied aspects relevant to a wide range of fields, including behavioural ecology, environmental adaptation and visual ecology. Although a variety of methods are available to measure animal colours, only few focus on chromatophores (specialized cells containing pigments) and pigment migration. Here, we illustrate a freely available and user-friendly method to quantify pigment cover (PiC) with high precision and low effort using digital images, where the foreground (i.e. pigments in chromatophores) can be detected and separated from the background. Images of the brown shrimp, Crangon crangon, were used to compare PiC with the traditional Chromatophore Index (CI). Results indicate that PiC outcompetes CI for pigment detection and transparency measures in terms of speed, accuracy and precision. The proposed methodology provides researchers with a useful tool to answer essential physiological, behavioural and evolutionary questions on animal colouration in a wide range of species.

Potential Antidepressant Constituents of Nigella sativa Seeds

BACKGROUND

Nigella sativa Linn. is well known seed in the Middle East, Asia, and the Far East as a natural remedy for many ailments and as a flavoring agent proclaimed medicinal usage dating back to the ancient Egyptians, Greeks, and Romans. An authentic saying of the Prophet Muhammad (Peace Be Upon Him) about black seed is also quoted in Al-Bukhari.

OBJECTIVE

This study was carried out to evaluate the antidepressant effect and isolate the potential antidepressant constituents of the polar extract of N. sativa seeds.

MATERIALS AND METHODS

The antidepressant effect was evaluated through the immobility duration in tail suspension and forced swim tests (FSTs). Albino mice were orally treated with N. sativa polar extract and its RP-18 column chromatography fractions (50 and 100 mg/kg,).

RESULTS

The polar extract and two of its sub-fractions were significantly able to decrease the immobility time of mice when subjected to both tail suspension and FSTs, the effects are comparable to standard drug (Sertraline, 5 mg/kg). However, these treatments did not affect the number of crossings and rearing in the open field test. Phytochemical investigation of the two active fractions led to the isolation of quercetin-3-O-α-L-rhamnopyranoside 1, quercetin-7-O-β-D-gluco- pyranoside 2, tauroside E 3, and sapindoside B as the potential antidepressant constituents.

SUMMARY

Phytochemical and biological evaluation the antidepressant constituents in Nigella sativa using the tail suspension and forced swim methods afforded the isolation and identification of quercetin-3-O-α-L rhamnopyranoside, quercetin-7-O-β-D gluco pyranoside, tauroside E, and sapindoside B as the potential antidepressant constituents in the polar extract of N. sativa. The isolated compounds were identified through extensive NMR analysis (1D, 2D, ESI MS). Abbreviations used: TST: Tail suspension test, FST: Forced swim test, OFT: An Open field test.

Understanding the ultrastructural aspects of berberine-induced skin-darkening activity in the toad, Bufo melanostictus, melanophores

Berberine is an active compound of Berberis vulgaris (Daruhaldi) with known multiple pharmacological activities, including antimicrobial, antiviral, anti-inflammatory, cholesterol-lowering, and anticancer effects. The present work aimed to study the ultrastructural effects of berberine to determine its skin-darkening potential using Bufo melanostictus melanophores, which has not been done to date. Light and electron microscopic analysis of isolated dorsal skin melanophores of B. melanostictus has been done after treatment with various concentrations of berberine, along with specific antagonists and agonists of β-adrenoceptors in order to explore the mechanism of action of berberine-induced skin darkening. The results showed that the number of melanophores with melanin-loaded dendrites increased in the subepidermal layer significantly in berberine-treated skin pieces in a dose-dependent manner leading to skin darkening. Highly electron-dense melanosomes of Stage IV increased considerably due to the enhanced process of melanization. These effects were found to be antagonized by propranolol, and were also found to be highly potentiated by isoprenaline, which is a specific β-adrenoceptor agonist. The findings show that berberine possesses a skin-darkening potential and could be used as a safe melanogenic agent for the treatment of hypopigmentation disorders or vitiligo.

Comparing Nigella sativa Oil and Fish Oil in Treatment of Vitiligo

Background:

Vitiligo is one of the autoimmune skin diseases that destroy the melanocytes of the skin. Moreover, its prevalence varies in different countries and regions.

Objectives:

The aim of this study was to compare the effect of Nigella sativa and fish oil on vitiligo lesions of the patients referred to a dermatology clinic.

Materials and Methods:

This randomized, double blind clinical trial was conducted in the dermatology clinic of the Imam Khomeini Hospital Ahvaz, Iran, from June to December 2011. We used a randomized simple sampling. From 96 patients with vitiligo, 52 eligible patients were selected and allocated to two groups with equal size. The study medications were applied twice a day by patients on their lesions. After six months, the improvement rate of lesions was assessed by the Vitiligo Area Scoring Index (VASI). Data were analyzed using SPSS v. 15; P value < 0.05 was considered as statistically significant.

Results:

After six months, a mean score of VASI decreased from 4.98 to 3.75 in patients applying topical Nigella sativa and from 4.98 to 4.62 in those using topical fish oil. Most of the percent improvement observed in upper extremities, trunk, head, and neck of those who received Nigella sativa and head, neck, trunk, and feet of those who received fish oil. No adverse effect was reported by the patients.

Conclusions:

Nigella sativa oil and fish oil were effective in reduction the size of patient’s lesions; however, Nigella sativa was more effective in comparison to the fish oil. Therefore, using Nigella sativa with the major drugs in the treatment of vitiligo is recommended.