Capsaicin reverses the inhibitory effect of licochalcone A/β-Arbutin on tyrosinase expression in b16 mouse melanoma cells

β-Arbutin and cisplatin: A combined approach to modulating apoptosis, cell viability, and migration in bladder cancer cells

One of the preferred treatments for bladder cancer, one of the most common cancers worldwide, is cisplatin-based chemotherapy. Since most tumor cells show cisplatin resistance, it is very important to discover new agents without adverse side effects. β-arbutin, a hydroquinone-β-D-glucopyranoside, has biological properties such as antioxidant, antimicrobial, anti-inflammatory, and anticancer, and is a phytochemical widely used as a skin whitener. In this study, β-arbutin was purified from the animal feed plant Onobrychis buhseana Boiss. (sainfoin). The study aimed to investigate the combined effects of cisplatin, a clinically used chemotherapeutic agent, and β-arbutin on HT-1376 bladder cancer cells for apoptosis, cell viability, and migration. In the study, after HT-1376 bladder cancer cells were cultured, optimum β-arbutin and cisplatin doses were determined on HT-1376 cells using the WST-1 test. To determine the apoptotic and migratory effects, flow cytometry and wound healing assays were performed. In HT-1376 cells, β-Arbutin led to greater apoptotoic and migratory effects when used alone and combined with Cisplatin (p < 0.0001 for apoptotic and migratory effects treated with β-Arbutin alone, p < 0.0001 for apoptotic and migratory effects when combined with Cisplatin). As a result, it can be suggested that β-arbutin may be a good drug candidate for treating bladder cancer.

Evaluating the Application Potential of a Recombinant Ganoderma Protein as Bioactive Ingredients in Cosmetics

The aim of this study was to evaluate the application potential of a recombinant fungal immunomodulatory protein from Ganoderma lucidum (rFIP-glu). First, a recombinant plasmid pPIC9K::FIP-glu-His was transferred into Pichia pastoris for the production of protein. The protein was then to assess its free radical scavenging abilities and the effect on the viability of both human immortalized keratinocytes (HaCaT cells) and mouse B16-F10 melanoma cells (B16 cells) in vitro, followed by the effect on the melanin synthesis of B16 cells. The results of SDS-PAGE and western blot showed that rFIP-glu was successfully expressed. Furtherly, a bioactivity assay in vitro indicated that the scavenging rate of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals reached 84.5% at 6.0 mg/mL (p ≤ 0.0001) of rFIP-glu, showing strong antioxidant activity. Subsequently, a safety evaluation demonstrated that rFIP-glu promoted the proliferation of HaCaT cells, with the cell viability reaching 124.3% at 48 μg/mL (p ≤ 0.01), regarding the cell viability of B16 cells after exposure to rFIP-glu (48 μg/mL) significantly inhibited, to 80.7% (p ≤ 0.01). Besides, rFIP-glu inhibited the melanin synthesis of B16 cells in a dose-dependent manner from 100–1000 μg/mL, and rFIP-glu at 500 μg/mL (p ≤ 0.01) exhibited the highest intracellular melanin amount reduction of 16.8%. Furthermore, a mechanism analysis showed that rFIP-glu inhibited tyrosinase (TYR) activity by up-regulating the expression of the microphthalmia-associated transcription factor (MITF) and down-regulating the gene expression of TYR and tyrosinase-related protein-1 (TYRP-1), thus inhibiting melanin synthesis. The data implied that rFIP-glu had significant antioxidant activity and whitening potency. It should be used as raw materials for cosmeceutical applications.

Phytochemicals as Immunomodulatory Agents in Melanoma

Cutaneous melanoma is an immunogenic highly heterogenic tumor characterized by poor outcomes when it is diagnosed late. Therefore, immunotherapy in combination with other anti-proliferative approaches is among the most effective weapons to control its growth and metastatic dissemination. Recently, a large amount of published reports indicate the interest of researchers and clinicians about plant secondary metabolites as potentially useful therapeutic tools due to their lower presence of side effects coupled with their high potency and efficacy. Published evidence was reported in most cases through in vitro studies but also, with a growing body of evidence, through in vivo investigations. Our aim was, therefore, to review the published studies focused on the most interesting phytochemicals whose immunomodulatory activities and/or mechanisms of actions were demonstrated and applied to melanoma models.

Artemisia argyi allelopathy: a generalist compromises hormone balance, element absorption, and photosynthesis of receptor plants

BACKGROUND

Allelopathy is expressed through the release of plant chemicals and is considered a natural alternative for sustainable weed management. Artemisia argyi (A. argyi) is widely distributed throughout Asia, and often dominates fields due to its strong allelopathy. However, the mechanism of A. argyi allelopathy is largely unknown and need to be elucidated at the physiological and molecular levels.

RESULTS

In this study, we used electron microscopy, ionomics analysis, phytohormone profiling, and transcriptome analysis to investigate the physiological and molecular mechanisms of A. argyi allelopathy using the model plant rice (Oryza sativa) as receptor plants. A. argyi water extract (AAWE)-treated rice plants grow poorly and display root morphological anomalies and leaf yellowing. We found that AAWE significantly inhibits rice growth by destroying the root and leaf system in multiple ways, including the integrity of ultrastructure, reactive oxygen species (ROS) homeostasis, and the accumulation of soluble sugar and chlorophyll synthesis. Further detection of the hormone contents suggests that AAWE leads to indole-3-acetic acid (IAA) accumulation in roots. Moreover, ionomics analysis shows that AAWE inhibits the absorption and transportation of photosynthesis-essential mineral elements, especially Mg, Fe, and Mn. In addition, the results of transcriptome analysis revealed that AAWE affects a series of crucial primary metabolic processes comprising photosynthesis in rice plants.

CONCLUSIONS

This study indicates that A. argyi realizes its strongly allelopathy through comprehensive effects on recipient plants including large-scale IAA synthesis and accumulation, ROS explosion, damaging the membrane system and organelles, and obstructing ion absorption and transport, photosynthesis and other pivotal primary metabolic processes of plants. Therefore, AAWE could potentially be developed as an environmentally friendly botanical herbicide due to its strong allelopathic effects.

Technologies for Solubility, Dissolution and Permeation Enhancement of Natural Compounds

The current review is based on the advancements in the field of natural therapeutic agents which could be utilized for a variety of biomedical applications and against various diseases and ailments. In addition, several obstacles have to be circumvented to achieve the desired therapeutic effectiveness, among which limited dissolution and/or solubility and permeability are included. To counteract these issues, several advancements in the field of natural therapeutic substances needed to be addressed. Therefore, in this review, the possible techniques for the dissolution/solubility and permeability improvements have been addressed which could enhance the dissolution and permeability up to several times. In addition, the conventional and modern isolation and purification techniques have been emphasized to achieve the isolation and purification of single or multiple therapeutic constituents with convenience and smarter approaches. Moreover, a brief overview of advanced natural compounds with multiple therapeutic effectiveness have also been anticipated. In brief, enough advancements have been carried out to achieve safe, effective and economic use of natural medicinal agents with improved stability, handling and storage.

Arbutin as a Skin Depigmenting Agent with Antimelanogenic and Antioxidant Properties

Arbutin is a compound of hydroquinone and D-glucose, and it has been over 30 years since there have been serious studies on the skin lightening action of this substance. In the meantime, there have been debates and validation studies about the mechanism of action of this substance as well as its skin lightening efficacy and safety. Several analogs or derivatives of arbutin have been developed and studied for their melanin synthesis inhibitory action. Formulations have been developed to improve the stability, transdermal delivery, and release of arbutin, and device usage to promote skin absorption has been developed. Substances that inhibit melanin synthesis synergistically with arbutin have been explored. The skin lightening efficacy of arbutin alone or in combination with other active ingredients has been clinically evaluated. Combined therapy with arbutin and laser could give enhanced depigmenting efficacy. The use of arbutin causes dermatitis rarely, and caution is recommended for the use of arbutin-containing products, especially from the viewpoint that hydroquinone may be generated during product use. Studies on the antioxidant properties of arbutin are emerging, and these antioxidant properties are proposed to contribute to the skin depigmenting action of arbutin. It is hoped that this review will help to understand the pros and cons of arbutin as a cosmetic ingredient, and will lead to future research directions for developing advanced skin lightening and protecting cosmetic products.

The Effect of Arbutin on The Expression of Tumor Suppressor P53, BAX/BCL-2 Ratio and Oxidative Stress Induced by Tert-Butyl Hydroperoxide in Fibroblast and LNcap Cell Lines

Objective

Arbutin (p-hydroxyphenyl-β-D-glucopyranoside) possesses beneficial functions including antioxidant, antiinflammatory, and anti-tumoral activities. Due to the important role of oxidative stress and apoptosis in the successful treatment of cancer, understanding mechanisms that lead to apoptosis in cancer cells, is essential. The purpose of the current study was to evaluate the effect of arbutin on tert-butyl hydroperoxide (t-BHP)-induced oxidative stress and the related mechanisms in fibroblast and Lymph Node Carcinoma of the Prostate (LNCaP) cells.

Materials and Methods

In this experimental study, the LNCaP and fibroblast cell lines were pre-treated with arbutin (50, 250 and 1000 μM). After 24 hours, t-BHP (30 and 35 μM) was added to the cells. Viability was measured (at 24 and 48 hours) using MTT assay. The antioxidant effect of arbutin was measured by FRAP assay. The mRNA expression of P53 and BAX/BCL-2 ratio were measured using quantitative polymerase chain reaction (PCR). The percentage of apoptotic or necrotic cells was determined using a double staining annexin V fluorescein isothiocyanate (FITC) apoptosis detection kit.

Results

Arbutin pre-treatment increased the total antioxidative power and cell viability in the MTT assay and reduced BAX/BCL-2 ratio, P53 mRNA expression and necrosis in fibroblasts exposed to the oxidative agent (P<0.001). In addition, our results showed that arbutin can decrease cell viability, induce apoptosis and increase BAX/BCL-2 ratio in LNCaP cells at some specific concentrations (P<0.001).

Conclusion

Arbutin as a potential functional β-D-glucopyranoside has strong ability to selectively protect fibroblasts against t-BHP-induced cell damage and induce apoptosis in LNCaP cells.

Licochalcone A restrains microphthalmia-associated transcription factor expression and growth by activating autophagy in melanoma cells via miR-142-3p/Rheb/mTOR pathway

Licochalcone A (LCA) was found to possess anticancer effects. This study aimed to investigate the anticancer effects and mechanisms of LCA in melanoma. A375 and B16 melanoma cells were stimulated with LCA, MTT assay was used to assess cell proliferation. Expression of miR-142-3p, microphthalmia-associated transcription factor (MITF, which regulates melanin production) and autophagy-related genes was determined by Real-time PCR or western blot. The apoptosis was analyzed by flow cytometry and caspase-3 activity. The roles of miR-142-3p and Ras homolog enriched in brain (Rheb) in LCA-affected cells were investigated by gain- and loss-of functions. LCA inhibited proliferation and MITF expression, but increased apoptosis and autophagy of melanoma cells. Moreover, LCA elevated miR-142-3p expression, but decreased its target gene Rheb expression. The effects of LCA on melanoma cells were abrogated by miR-142-3p inhibitor or Rheb overexpression. LCA suppressed mTOR signaling activation via Rheb. Additionally, rapamycin (a mTOR antagonist) notably attenuated the effects of Rheb on the autophagy, proliferation, apoptosis, and MITF expression in LCA-treated melanoma cells. In conclusion, LCA restrained MITF expression and growth by activating autophagy in melanoma cells via miR-142-3p/Rheb/mTOR pathway. This study suggested that LCA might be a potential therapeutic candidate for prevention and treatment of melanoma.

α-Glucosidase, α-amylase, and tyrosinase inhibitory potential of capsaicin and dihydrocapsaicin

Chili is a spicy plant and is widely used in traditional medicine. Capsaicin and dihydrocapsaicin belong to the capsaicinoid group, which is produced from chili. This study aims to investigate the antidiabetic properties and anti-melanin synthesis of capsaicinoids by studying the inhibitory activity of capsaicin and dihydrocapsaicin with α-glucosidase, α-amylase, and tyrosinase. The results revealed that dihydrocapsaicin with IC₅₀ had 4.13-fold and 3.00-fold for α-glucosidase and α-amylase, respectively, which are lower than capsaicin. Moreover, the IC₅₀ of capsaicin with tyrosinase had 1.73 times less than dihydrocapsaicin. The inhibition constant (K_i ) also supported that the dihydrocapsaicin had higher inhibitory activity than capsaicin against α-glucosidase and α-amylase, but lower inhibitory activity than capsaicin on tyrosinase. Capsaicin and dihydrocapsaicin functioned in mixed-type inhibition on each enzyme, except that capsaicin functioned in competitive inhibition of tyrosinase. The results indicated that capsaicin and dihydrocapsaicin had more potent anti-melanin synthesis than antidiabetic properties. PRACTICAL APPLICATIONS: This study presents the inhibition potential of capsaicin and dihydrocapsaicin on antidiabetes and anti-melanin properties by standard methods for inhibitory activity against α-glucosidase, α-amylase, and tyrosinase. We suggest the application of these results in the development of antidiabetes and anti-melanin drugs for pharmaceutical and cosmetic industries.